title stringlengths 0 1.13k | abstract stringlengths 1 15.7k | PMID int64 22 36.5M |
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Dual-source CT coronary angiography in patients with atrial fibrillation: comparison with single-source CT. | To evaluate the performance of dual-source computed tomography (DSCT) for the visualization of the coronary arteries in a population with atrial fibrillation (AF) compared to single-source CT (SSCT) and to explore the impact of patients' heart rate (HR) on image quality (IQ) and reconstruction timing. Thirty consecutive patients (11 male, 19 female; 69.0+/-9.2 years old) with suspected coronary artery disease and permanent AF were examined on a DSCT scanner (120 kV, 400 mAs/rot, 0.33 s rotation time, 64 x 0.6 mm collimation, pitch 0.20-0.28, Siemens Somatom Definition). Patients were divided into two groups: low and medium HR group (HR<or=80 bpm, n=14) and high HR group (HR>80 bpm, n=16). Five of the patients also underwent conventional coronary angiography (CAG). The raw data from both tube detector arrays were reconstructed as DSCT data using a routine algorithm (temporal resolution of 83 ms). The raw data from one tube detector array was reconstructed separately on the same system using a routine single source algorithm (temporal resolution of 83-165 ms) and defined as virtual SSCT data. Image quality was assessed using a four-point grading scale from excellent (1) to non-assessable (4). IQ of the DSCT data was significantly better than that of the virtual SSCT data (mean score 1.33+/-0.61 vs. 1.80+/-1.02; Z=-8.755, P=0.000). 98.6% of the segments shown in DSCT were diagnostic, compared with 89.9% of the segments in virtual SSCT, chi(2)=32.595, P=0.000. In DSCT group, IQ of low HR group was also better than that of high HR group, although the difference was not as big (mean score 1.25+/-0.52 vs. 1.38+/-0.66; Z=-2.227, P=0.026). The mean HR of low HR group and high HR group were 67.4+/-8.5 beats per minute (bpm) and 94.2+/-8.8 bpm (t=-8.499, P=0.000). The range of the variation of HR was higher in high HR group than in low HR group (mean difference between maximum and minimum HR 79.5+/-21.0 vs. 49.9+/-21.1 bpm; t=-3.845, P=0.001). In 23 (77%) patients optimal IQ was achieved within one phase for all three main arteries. In low HR group, the optimal phase was distributed evenly between diastole and systole; but in high HR group, the optimal phase shifted to systole in most cases (92%). In five cases these results were compared to CAG results to look for the ability to identify stenosis with a diameter reduction of more than 50% of the lumen. With DSCT it was possible to diagnose 20 of 21 stenosis and 48 of 49 non-stenosed vessel segments correctly. With SSCT 19 of 21 stenosis and 45 of 49 non-stenosed vessel segments were diagnosed correctly according to CAG. Due to its high temporal resolution, DSCT provides images of full diagnostic image quality in patients with AF, which otherwise would be excluded from CT examinations. The number of assessable segments for DSCT is still somewhat less than in non-AF patients, but in opposition to SSCT still valid for routine diagnostic imaging. Patients' HR had impact on IQ and reconstruction timing. | 18,993,003 |
[A case of acquired encephalopathy in a child. A cause that we thought had disappeared]. | Subacute central nervous system infection must be considered in any infant presenting with progressive encephalopathy. We present the case of an 18-month-old child with normal neuromotor development until the age of 14 months admitted for spastic hypertonia of the legs and arms associated with axial hypotonia. The mother reported that she recently had been found to be HIV-seropositive. HIV antibodies were negative during the first trimester of pregnancy. On the child's blood sample, the HIV test was positive associated with a major decrease in CD4 cell count. Viral load (ARN-PCR) was 720 copies par millilitre. On brain MRI, hypersignals were found in the white matter. HIV related encephalopathy caused by maternal fetal transmission was diagnosed. After 2 months of antiretroviral treatment (azidothymidine, lamivudine, and boosted lopinavir), the child's neurological condition improved. HIV infection must be suspected in all infants with progressive encephalopathy. The HIV test in pregnant women must be proposed at the beginning of pregnancy and repeated during the last trimester. | 18,993,038 |
Maternal dexamethasone and GLP-2 have early effects on intestinal sugar transport in their suckling rat offspring. | Both glucagon-like peptide 2 (GLP-2) and glucocorticosteroids enhance intestinal uptake in mature animals. Maternal stimuli may cause intestinal adaptation in the offspring. We hypothesized that administering GLP-2, dexamethasone (DEX) or a combination of GLP-2+DEX to rat dams during pregnancy and lactation would enhance intestinal sugar uptake in their offspring. Rat dams were treated with GLP-2 (0.1 microg/g/day), DEX (0.128 microg/g/day), a combination of GLP-2+DEX or placebo. Glucose and fructose uptake was assessed in their suckling offspring using an in vitro intestinal ring uptake technique. The protein abundance of SGLT1, GLUT5, GLUT2, Na(+)K(+)-ATPase and selected signals was determined by immunohistochemistry; GLP-2 caused hypertrophy of the jejunal enterocytes and increased ileal villous height. Jejunal fructose uptake was reduced by GLP-2, DEX and GLP-2+DEX. V(max) for jejunal glucose uptake was reduced with DEX and GLP-2+DEX. These declines were not explained by alterations in transporter abundance. Decreases in Akt and mTOR abundance were associated with declines in transporter activity. We speculate that the intrinsic activity of the sugar transporters was modified via the P13K pathway. In conclusion, maternal GLP-2 and DEX reduced intestinal sugar uptake in their offspring. This may have nutritional implications for the offspring of mothers treated with GLP-2 or steroids. | 18,993,047 |
A combination of aspirin and gamma-tocopherol is superior to that of aspirin and alpha-tocopherol in anti-inflammatory action and attenuation of aspirin-induced adverse effects. | Nonsteroidal anti-inflammatory drugs such as aspirin are used for pain relief and chemoprevention against cancer, but frequently cause gastric mucosal injury. We examined whether combinations of aspirin and alpha-tocopherol (alphaT) or aspirin and gamma-tocopherol (gammaT), with alphaT and gammaT being the two major forms of vitamin E, are better anti-inflammatory agents than aspirin alone, and whether these combinations alleviate aspirin-associated side effects. In the carrageenan-induced air-pouch inflammation model in the rat, aspirin (150 mg/kg) or a combination of aspirin and gammaT (33 mg/kg) inhibited proinflammatory prostaglandin E(2) (PGE(2)) by 70% (P<.02) at the inflammation site 6 h after inflammation was initiated. However, at 18 h, only the combination decreased exudate volume (15%; P<.05) and showed modest inhibition of PGE(2) (40%; P<.07) and lactate dehydrogenase activity (30%; P=.07) in the fluid collected at the inflammation site. gammaT, but not alphaT, spared aspirin-induced reduction in food intake, partially reversed aspirin-depressed gastric PGE(2) and attenuated stomach lesions. Surprisingly, the combination of aspirin and alphaT (33 mg/kg) did not show more benefits than aspirin alone, but worsened gastric injury and food intake reduction. Our study demonstrated that a combination of aspirin and gammaT, but not a combination of aspirin and alphaT, has some advantage over aspirin alone in terms of anti-inflammatory effects and attenuation of aspirin-induced adverse effects. This combination may be useful in complementing aspirin in the treatment of chronic inflammatory conditions and cancer. | 18,993,050 |
Isomer-specific effects of conjugated linoleic acid on gene expression in RAW 264.7. | Conjugated linoleic acid (CLA) is a mixture of dietary fatty acids that has various beneficial effects including decreasing cancer, atherosclerosis, diabetes and inflammation in animal models. Some controversy exists on the specific isomers of CLA that are responsible for the benefits observed. This study was conducted to examine how different CLA isomers regulate gene expression in RAW 264.7. A mouse macrophage cell line, RAW 264.7, was treated with five different CLA isomers (9E,11E-, 9Z,11E-, 9Z,11Z-, 10E,12Z- and 11Z,13E-CLA). Gene expression microarrays were performed, and several significantly regulated genes of interest were verified by a real-time polymerase chain reaction (PCR). Examination of the biological functions of various significantly regulated genes by the five CLA isomers showed distinct properties. Isomers 9E,11E-, 9Z,11Z-, 10E,12Z- and 11Z,13E-CLA decreased production of proinflammatory cytokines such as interleukin (IL)-1alpha, IL-1beta and IL-6. Many of CLA's effects are believed to be mediated by the fatty acid receptors such as the peroxisome proliferator-activated receptors (PPAR) and retinoid-X-receptors (RXR). Using PPAR and RXR specific antagonists and coactivator recruitment assays, it was evident that multiple mechanisms were responsible for gene regulation by CLA isomers. Coactivator recruitment by CLA isomers showed their distinct properties as selective receptor modulators for PPARgamma and RXRalpha. These studies demonstrate distinct isomer differences in gene expression by CLA and will have important ramifications for determining the potential therapeutic benefit of these dietary fatty acids in prevention of inflammation-related diseases. | 18,993,052 |
Mitochondrial and sarcoplasmic protein changes in hearts from copper-deficient rats: up-regulation of PGC-1alpha transcript and protein as a cause for mitochondrial biogenesis in copper deficiency. | Changes in mitochondrial and sarcoplasmic proteins using proteinomics and Western blotting in hearts from copper-deficient rats were explored in this study. Also, key enzymes that are involved in cardiac energy metabolism via glycolysis and fatty acid oxidation and related transcription factors were determined. Rats were fed one of two diets: a copper-adequate diet containing 6 mg Cu/kg diet or a diet with less than 1 mg Cu/kg diet for 5 weeks. Copper deficiency was confirmed by low liver copper levels, decreased hematocrit levels and cardiac hypertrophy. Proteinomic data revealed that of the more than 50 proteins identified from the mitochondrial fraction of heart tissue, six were significantly down-regulated and nine were up-regulated. The proteins that were decreased were beta enolase 3, carbonic anhydrase 2, aldose reductase 1, glutathione peroxidase, muscle creatine kinase and mitochondrial aconitase 2. The proteins that were up-regulated were isocitrate dehydrogenase, dihydrolipoamide dehydrogenase, transferrin, subunit d of ATP synthase, transthyretin, preproapolipoprotein A-1, GRP 75, alpha-B crystalline and heat shock protein alpha. Follow-up Western blots on rate-limiting enzymes in glycolysis (phosphofructose kinase), fatty acid oxidation (medium chain acyl dehydrogenase, peroxisome proliferator-actvator receptor-alpha or PPARalpha) and gluconeogenesis (phosphoenolpyruvate carboxykinase) did not reveal changes in metabolic enzymes. However, a significant increase in peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha protein, as well as the transcript, which increased 2.5-fold, was observed. It would appear that increased mitochondrial biogenesis known to occur in copper deficiency hearts is caused by an increased expression in the master regulator of mitochondrial biogenesis, PGC-1alpha. | 18,993,053 |
Topoisomerase II alpha as a marker predicting anthracyclines' activity in early breast cancer patients: ready for the primetime? | This manuscript reviews and discusses results from randomised clinical studies evaluating topoisomerase II alpha (topo II) as a marker predicting anthracyclines' activity in early breast cancer patients. A Medline search has led to the identification of six phase III clinical trials, in which topo II has been retrospectively evaluated as a marker predicting anthracyclines' activity in the adjuvant setting. Rates of topo II gene aberrations, in particular gene deletion, seem to vary substantially between the studies. No extensive correlation has been found between topo II gene status and protein levels. Five of the six trials suggest that topo II gene amplification is associated with increased tumour sensitivity to anthracyclines. Two of the three studies evaluating topo II gene deletions suggest that topo II deleted tumours might also derive an increased benefit from anthracyclines. Current data suggest that topo II might become a predictive tool to identify patients candidate to receive anthracyclines in the adjuvant setting. Ongoing studies will likely address some pending issues which, at present, prevent the use of this marker in daily practice. | 18,993,056 |
Cadmium tolerance and adsorption by the marine brown alga Fucus vesiculosus from the Irish Sea and the Bothnian Sea. | Cadmium (Cd) uptake capacities and Cd tolerance of the marine alga Fucus vesiculosus from the Irish Sea (salinity 35 psu) and from the Bothnian Sea (northern Baltic, 5 psu) were quantified. These data were complemented by measurements of changes in maximal photosynthetic rate (P(max)), dark respiration rate and variable fluorescence vs. maximal fluorescence (F(v):F(m)). At concentrations between 0.01 and 1 mmol Cd l(-1), F. vesiculosus from the Bothnian Sea adsorbed significantly more (about 98%) Cd compared with F. vesiculosus from the Irish Sea. The photosynthetic measurements showed that the Bothnian Sea F. vesiculosus were more sensitive to Cd exposure than the Irish Sea algae. The algae from the Irish Sea showed negative photosynthetic effects only at 1 mmol Cd l(-1), which was expressed as a decreased P(max) (-12.3%) and F(v):F(m) (-4.6%). On the contrary, the algae from the Bothnian Sea were negatively affected already at Cd concentrations as low at 0.1 mmol Cd l(-1). They exhibited increased dark respiration (+11.1%) and decreased F(v):F(m) (-13.9%). The results show that F. vesiculosus from the Bothnian Sea may be an efficient sorption substrate for Cd removal from Cd contaminated seawater and this algae type may also have applications for wastewater treatment. | 18,993,059 |
Attention-dependent representation of a size illusion in human V1. | One of the most fundamental properties of human primary visual cortex (V1) is its retinotopic organization, which makes it an ideal candidate for encoding spatial properties, such as size, of objects. However, three-dimensional (3D) contextual information can lead to size illusions that are reflected in the spatial pattern of activity in V1 [1]. A critical question is how complex 3D contextual information can influence spatial activity patterns in V1. Here, we assessed whether changes in the spatial distribution of activity in V1 depend on the focus of attention, which would be suggestive of feedback of 3D contextual information from higher visual areas. We presented two 3D rings at close and far apparent depths in a 3D scene. When subjects fixated its center, the far ring appeared to be larger and occupy a more eccentric portion of the visual field, relative to the close ring. Using functional magnetic resonance imaging, we found that the spatial distribution of V1 activity induced by the far ring was also shifted toward a more eccentric representation of the visual field, whereas that induced by the close ring was shifted toward the foveal representation, consistent with their perceptual appearances. This effect was significantly reduced when the focus of spatial attention was narrowed with a demanding central fixation task. We reason that focusing attention on the fixation task resulted in reduced activity in--and therefore reduced feedback from--higher visual areas that process the 3D depth cues. | 18,993,076 |
Strategies for generating less toxic P-selectin inhibitors: pharmacophore modeling, virtual screening and counter pharmacophore screening to remove toxic hits. | This paper describes the generation of ligand-based as well as structure-based models and virtual screening of less toxic P-selectin receptor inhibitors. Ligand-based model, 3D-pharmacophore was generated using 27 quinoline salicylic acid compounds and is used to retrieve the actives of P-selectin. This model contains three hydrogen bond acceptors (HBA), two ring aromatics (RA) and one hydrophobic feature (HY). To remove the toxic hits from the screened molecules, a counter pharmacophore model was generated using inhibitors of dihydrooratate dehydrogenase (DHOD), an important enzyme involved in nucleic acid synthesis, whose inhibition leads to toxic effects. Structure-based models were generated by docking and scoring of inhibitors against P-selectin receptor, to remove the false positives committed by pharmacophore screening. The combination of these ligand-based and structure-based virtual screening models were used to screen a commercial database containing 538,000 compounds. | 18,993,099 |
Nodular fasciitis with cortical involvement. | We report on the clinical and imaging features--including CT and MRI--of nodular fasciitis with cortical involvement in the shoulder. Nodular fasciitis is a commonly encountered benign soft-tissue fibrous tumor that typically involves the upper extremity and may be mistaken for a sarcomatous lesion because of its rapid growth. Lesions of the intramuscular subtype, because of their large size and deep location, usually require preoperative MR-imaging. This case is the first reported to our knowledge of nodular fasciitis producing erosion of the cortical surface in the appendicular skeleton. | 18,993,101 |
Application of portable Raman instruments for fast and non-destructive detection of minerals on outcrops. | Raman spectral signatures have been obtained in situ for a series of minerals using portable Raman instruments. Cerussite, anglesite, wulfenite, titanite, calcite, tremolite, andradite and quartz were detected using portable Raman spectrometer First Defender XL (Ahura). Baryte, almandine and realgar Raman spectra obtained by this instrument in the field were compared to the data measured by the other mobile Raman instrument Inspector Raman (DeltaNu). Bench Raman dispersive microspectrometer (InVia Reflex, Renishaw) was used for comparative purposes. All spectra were obtained using a 785nm diode excitation. Although displaying lower spectral resolution comparing with the laboratory confocal instrument both portable instruments permit unambiguous detection of minerals in the field. These possibilities designate portable Raman machines as excellent tools for field geological applications. Miniaturised Raman instrument combined with LIBS will be included in the payload of the EXO Mars mission and would open interesting research possibilities in other in situ field planetary studies. | 18,993,111 |
Seasonal pattern of incidence and case fatality of acute myocardial infarction in a Japanese population (from the Takashima AMI Registry, 1988 to 2003). | We examined the seasonal variations in the incidence and case fatality of acute myocardial infarction (AMI) in a geographically defined population using 16-year AMI registration data. It remains unclear whether the incident events of AMI display any seasonal variation. Documentation of such a pattern may foster investigation for understanding the potential mechanisms responsible for these effects and may provide novel avenues for prevention of AMI. Data were obtained from the Takashima AMI Registry, which covers an entire community of approximately 55,000 in central Japan. There were 335 definite cases of AMI during 1988 to 2003 (217 men, 118 women). Of these, there were 96 fatal cases (53 men, 43 women) within 28 days of onset. Incidence rates (per 100,000 person-years) and case fatality rates with 95% confidence intervals (CI) were calculated across seasons. Poisson regression analysis was used to calculate the incidence rate, and case fatality ratios adjusted for age and gender. The AMI incidence rate was higher in winter (44.9, 95% CI 35.9 to 53.9) and spring (44.1, 95% CI 35.3 to 52.9) than the other seasons. After adjustment for age and gender, AMI risk was 1.4 (95% CI 1.03 to 1.9) times higher in winter and was 1.4 (95% CI 1.01 to 1.9) times higher in spring than summer. The 28-day AMI case fatality rate was also higher in winter (34.4%, 95% CI 24.9 to 43.9) and spring (32.3%, 95% CI 22.9 to 41.7). Age- and gender-adjusted fatality risk was 2.4 (95% CI 1.2 to 4.9) times higher in winter and 2.3 (95% CI 1.1 to 4.6) times higher in spring than summer. In conclusion, higher AMI incidence and case fatality rates were observed in winter and spring in a Japanese population. | 18,993,146 |
Echocardiographic and clinical risk factors for atrial fibrillation in hypertensive patients with ischemic stroke. | Atrial fibrillation (AF) is a common cause of ischemic stroke. Because anticoagulation can prevent many of these strokes, identifying patients with occult intermittent AF is important. Hypertension is a common precursor of stroke and AF. Prolonged nonselective electrocardiographic monitoring of patients after ischemic stroke has yielded only a small number of patients with occult intermittent AF. To determine the importance of AF in nonhemorrhagic stroke, we retrospectively studied 799 patients admitted with ischemic stroke over 31 months. AF was present on the admitting electrocardiogram in 154 patients (19.3%), diagnosed later during the stroke admission in 58 (7.3%), and found only during another admission before/after the stroke admission in 46 (5.8%). AF was intermittent in 123 patients, 47.7% (95% CI 41.6 to 53.8) of patients with AF, and not present on initial electrocardiogram in 40.3% of patients with AF. In 633 patients with hypertension, AF occurred in 34.9% versus 22.2% without hypertension (p <0.01). Echocardiogram revealed a left atrium > or =4.0 cm in 81.3% of patients with AF versus 42.4% of those without AF (odds ratio [OR] 5.85, 95% confidence interval [CI] 3.87 to 8.96, p <0.001); ejection fraction was <50% in 27.7% of patients with AF versus 12.6% of those without AF (OR 2.63, 95% CI 1.65 to 4.22, p <0.001); and the left ventricle was > or =5.6 cm in 13.8% in patients with AF versus 6.7% in those without AF (OR 2.21, 95% CI 1.61 to 3.04, p <0.01). Clinically, congestive heart failure (31% vs 10.4%, OR 3.89, 95% CI 2.76 to 5.73) and coronary disease (31% vs 21.4%, OR 1.65, 95% CI 1.15 to 2.37) were present more often in patients with AF (p <0.001). Left ventricular hypertrophy, diastolic dysfunction, and diabetes were common in all hypertensive patients with stroke. In conclusion, hypertensive patients with these risk factors should undergo prolonged electrocardiographic event monitoring to identify occult intermittent AF so measures can be taken to prevent a second stroke and possibly a first stroke. | 18,993,153 |
Doppler-catheter discrepancies in patients with bileaflet mechanical prostheses or bioprostheses in the aortic valve position. | The aims of the present study were to investigate in vivo Doppler-catheter discrepancies in aortic bileaflet mechanical and stented biologic valves and evaluate whether these can be predicted using Doppler echocardiography. Results of in vitro studies of bileaflet mechanical valves suggested overestimation using Doppler gradients. Findings in stented biologic valves were conflicting. Patients who underwent valve replacement with a St. Jude Medical mechanical (n = 14, size 19 to 29) or a St. Jude Medical Biocor (Biocor, n = 13, size 21 to 25) valve were included. Simultaneous continuous Doppler recordings (transesophageal transducer) and left ventricular and aortic pressure measurements were performed using high-fidelity catheters. Gradients after pressure recovery were predicted from Doppler using a validated equation. Doppler overestimated catheter gradients in both the mechanical and Biocor. Mean Doppler catheter differences for the mechanical/Biocor were for mean gradients of 4 +/- 3 (SD; p = 0.002)/6 +/- 4 mm Hg (p = 0.002). There was a strong relation between catheter and Doppler gradients (r = 0.85 to 0.92). Doppler catheter discrepancy as a percentage of the Doppler mean gradient for the mechanical was median 41% (range -30% to 76%) and for the Biocor was median 35% (range -7% to 75%). The catheter-Doppler discrepancy was not significant using the predicted net gradient from Doppler. In conclusion, this was the first in vivo investigation of prosthetic valves using simultaneous Doppler and high-fidelity catheters. Doppler overestimated catheter gradients in both mechanical and stented biologic valves. However, the discrepancy can be predicted considering pressure recovery in the aorta. | 18,993,160 |
The relationship of endometriosis and ovarian malignancy: a review. | To review the malignant potential of endometriosis based on epidemiologic, histopathologic, and molecular data. Literature review. The pathogenesis of endometriosis remains unclear. The histopathologic development of endometriosis has undergone long-term investigation. Studies have confirmed histologic transition from benign endometriosis to ovarian malignancy, including malignant transformation of extraovarian endometriosis. The prevalence of endometriosis in patients with epithelial ovarian cancer, especially in endometrioid and clear cell types, has been confirmed to be higher than in the general population. Ovarian cancers and adjacent endometriotic lesions have shown common genetic alterations, such as PTEN, p53, and bcl gene mutations, suggesting a possible malignant genetic transition spectrum. Furthermore, endometriosis has been associated with a chronic inflammatory state leading to cytokine release. These cytokines act in a complex system in which they induce or repress their own synthesis and can cause unregulated mitotic division, growth and differentiation, and migration or apoptosis similar to malignant mechanisms. The malignant potential of endometriosis holds serious implications for management, such as the need for earlier and more meticulous surgical intervention for complete disease treatment. | 18,993,168 |
Diabetic nephropathy: important pathophysiologic mechanisms. | With the global epidemic of type 2 diabetes mellitus, diabetes has become the leading cause of end stage renal failure (ESRF) in most Western countries. Approximately 20-30% of all diabetic subjects will develop evidence of diabetic nephropathy, which represents a continuum from microalbuminuria, to overt nephropathy or macroalbuminuria, and finally ESRF. While there have been significant breakthroughs in the last decade with regards to the prevention and treatment of diabetic kidney disease, in particular blockade of the renin angiotensin system, there is a vital need to identify and target novel pathophysiologic pathways such as advanced glycation which appear to be centrally involved in diabetic renal disease in order to reduce the rising burden of this disease. | 18,994,672 |
Hand hygiene compliance monitoring: current perspectives from the USA. | Monitoring hand hygiene compliance and providing healthcare workers with feedback regarding their performance are considered integral parts of a successful hand hygiene promotion program. Direct observation of care providers by trained personnel is currently considered the gold standard. Advantages include the ability to determine if hand hygiene is being performed at the correct times, establish compliance rates by healthcare worker type, and assess hand hygiene technique. However, observation surveys are time-consuming, permit observation of only a small fraction of all hand hygiene opportunities, and can be influenced by inter-rater reliability. Comparison of compliance rates obtained through observation surveys is problematic due to lack of standardization of criteria for compliance and observation techniques. Self-reporting of compliance is not sufficiently reliable to be useful. Monitoring the usage of hand hygiene products requires much less time and can be performed on an ongoing basis, and is less complicated. However, it does not provide information about the appropriateness and quality of hand hygiene practices or compliance rates by health-care worker type. Furthermore, it is not clear how product usage correlates with compliance established by observational surveys. Electronic methods for monitoring compliance require further evaluation before they can be routinely recommended. Clearly, further research is needed to develop efficient, reliable, and reproducible methods for monitoring hand hygiene compliance. | 18,994,674 |
[Plastic bronchitis: report of a pediatric case]. | Plastic bronchitis (PB) is a rare disease, characterized by the formation of obstructive branching airways tracheobronchial casts. Commonly, PB often complicates the course of cardiac or respiratory disorders. The occurrence of PB before manifestation of the underlying respiratory disease is unusual. We report on the case of a boy, aged three years and eight months, free from underlying pulmonary disease, who presented with extensive atelectasis of the left lung during an acute respiratory tract infection. Bronchoscopy revealed the obstruction of the left tracheobronchial tree with large purulent casts. After bronchoscopic removal of the casts, the boy became asymptomatic. Initial aetiological investigations were negative. Two years later, the patient developed an asthma. | 18,995,152 |
Hope, optimism, and self-care among Better Breathers Support Group members with chronic obstructive pulmonary disease. | The objective of this study was to determine the levels of hope, optimism, and self-care of persons with chronic obstructive pulmonary disease (COPD) who attend community-based Better Breathers Support Group (BBSG) meetings. A convenience sample of 68 BBSG members from 14 groups in three southeastern states participated. The data were collected with a questionnaire set composed of a demographic form and three previously tested research instruments: the Herth Hope Index (HHI), the Alberto Chronic Obstructive Pulmonary Disease Self-care Behavior Inventory (COPDSC), and the Life Orientation Test--Revised (LOT-R). The findings (n = 68) include a significant and positive relationship between the HHI and COPDSC (r = .39; p > .01), between the LOT-R and COPDSC (r = .41; p > .001), and between the LOT-R and HHI (r = .59; p > .001). So, those participants with higher Hope and Optimism have higher levels of Self-care. We concluded the participants were fairly optimistic (LOT-R average = 23.75+/-4.49) and hopeful (HHI average 39.47+/-5.61). The average score on the COPDSC was 141.57 (+/-14.76) indicating a high level of self-care. | 18,995,163 |
A randomized clinical trial of the clinical effects of enhanced heart failure monitoring using a computer-based telephonic monitoring system in older minorities and women. | Prior studies suggest that disease management programs may be effective in improving clinical outcomes in patients with heart failure (HF). However, the use of these programs in settings with limited sources and among diverse population is not know. Thus the present study was designed to assess the impact of a computer-based home disease management program (Alere DayLink HF Monitoring System [HFMS]) on the clinical outcomes of Medicare beneficiaries with HF who were elderly, women, and non-white males who received the care from a community-based primary care practitioner. The Heart Failure Home Care (HFHC) trial was a multicenter, randomized, controlled trial of HFMS versus standard heart failure care (SC: enhanced patient education, education to clinicians, and follow-up). The primary study end point was treatment failure, defined as a composite of cardiovascular death or rehospitalization for heart failure within 6 months of enrollment. Among patients rehospitalized for HF, length of hospital stay was also considered a primary end point. A total of 315 patients were randomized: 160 to HFMS and 155 to SC. Although the incidence of the primary outcome was somewhat higher in the SC arm (28.8% versus 21.2%, P = .15), the difference was not statistically different. The length of hospital stay was also similar in both groups. Our study results suggest that enhanced patient education and follow-up is as successful as a sophisticated home monitoring device with an interactive program in patients with HF who are elderly, women and non-Caucasian males and receive the care from a community-based primary care practitioner. | 18,995,174 |
Activation of inducible NOS in peripheral vessels and outcomes in heart failure patients. | Activation of inducible nitric oxide synthase (iNOS) has been reported in congestive heart failure (CHF) conditions. However, it is unknown whether activation of iNOS affects prognosis of CHF patients. We prospectively studied the influence of activation of iNOS in the forearm on the outcome of CHF patients. Forearm blood flow (FBF) responses to 3 doses of acetylcholine (ACh) and nitroglycerin (NTG), and 4 doses of a selective iNOS inhibitor (aminoguanidine: Amn) and a nonselective NOS inhibitor (L-NMMA) were examined using plethysmography in 68 patients with CHF from idiopathic dilated cardiomyopathy. Plasma brain natriuretic peptide (BNP) and tumor necrosis factor-alpha (TNF-alpha) were also measured in all patients. During the mean follow-up period of 3.8 years, 25 patients were hospitalized for worsening heart failure and 9 of these patients died. Patients with adverse events had a diminished vasodilator response to ACh (P < .001) compared to patients without adverse events. Amn significantly decreased FBF (P < .001) in patients with adverse events, but not in patients without adverse events. FBF responses to NTG and L-NMMA were not significantly different between the 2 groups. When grouped by maximum FBF responses to each drug above and below the median value, multivariate Cox proportional hazards model analyses for cardiac event showed a significance in the FBF response to Amn (adjusted hazard ratio 5.89, P < .001). FBF responses to maximum dose of Amn significantly correlated with BNP and TNF-alpha levels (both P < .001). CHF patients with vascular iNOS activation, as demonstrated by a greater vasoconstrictor response to Amn, had poor outcomes. Activation of iNOS in peripheral vessels, associated with proinflammatory cytokines in accordance to the severity of heart failure, is a marker for, or contributes to, adverse events in patients with CHF. | 18,995,176 |
Serial sampling of ST2 predicts 90-day mortality following destabilized heart failure. | To prospectively determine the prognostic utility of serial sampling of the interleukin-1 receptor family member, ST2, for predicting 90-day mortality in patients with heart failure (HF) admitted to a Veteran Affairs Medical Center. A total 150 patients hospitalized with acutely destabilized HF were followed at the Veteran Affairs Healthcare System in San Diego, CA. Multiple cardiac-related parameters were measured including ST2, B-type natriuretic peptide (BNP), NT-proBNP, and blood urea nitrogen (BUN). Plasma samples were collected at 6 time points between admission and discharge. Biomarker concentrations were correlated to survival at 90 days. Uni- and multivariate analyses were used to identify prognostic variables. From admission to discharge, percent change in ST2 was strongly predictive of 90-day mortality: those patients whose ST2 values decreased by 15.5% or more during the study period had a 7% chance of death, whereas patients whose ST2 levels failed to decrease by 15.5% in this time interval had a 33% chance of dying. Percent change in ST2 concentrations during acute HF treatment is predictive of 90-day mortality and was independent of BNP or NT-proBNP levels. ST2 may provide clinicians with an additional tool for guiding treatment in patients with acute destabilized HF. | 18,995,177 |
Epithelioid smooth muscle tumors of the uterus do not express CD1a: a potential immunohistochemical adjunct in their distinction from uterine perivascular epithelioid cell tumors. | Uterine epithelioid smooth muscle tumors and uterine perivascular epithelioid cell tumors (PEComas) are known to display such a substantial overlap in morphologic and immunophenotypic characteristics that the existence of the latter as a distinct clinicopathologic entity at this location has been called into question. Recent research suggests that the constituent entities of the PEComa family at all anatomical locations, including lymphangioleiomyomatosis of the uterus, uniformly display immunoreactivity for CD1a. The purpose of this study is to determine the proportion of uterine epithelioid smooth muscle tumors that may similarly be CD1a-positive. Representative sections from 18 archived epithelioid smooth muscle tumors of the uterine corpus (6 epithelioid leiomyosarcomas and 12 epithelioid leiomyomas), diagnosed and classified as such based on World Health Organization criteria, were subjected to immunohistochemical stains for CD1a and HMB-45. The epithelioid component of the tissue sections evaluated ranged from 10% to 100% (mean, 70%). Two cases were composed predominantly of cells with overtly clear cytoplasm. All cases were entirely negative for CD1a. Of 18 cases, 1 (5.5%) (an epithelioid leiomyosarcoma) displayed immunoreactivity for HMB-45 in scattered lesional cells that constituted approximately 5% of the overall tumoral volume for the case. All others were HMB-45-negative. Given their rarity, future studies are required to confirm that all PEComas of the uterus are indeed uniformly positive for CD1a. However, if the latter staining pattern is confirmed, our findings herein suggest that CD1a may be a useful immunohistochemical adjunct in distinguishing uterine epithelioid smooth muscle tumors from uterine PEComas. | 18,995,203 |
Understanding synapses: past, present, and future. | Classical physiological work by Katz, Eccles, and others revealed the central importance of synapses in brain function, and characterized the mechanisms involved in synaptic transmission. Building on this work, major advances in the past two decades have elucidated how synapses work molecularly. In the present perspective, we provide a short description of our personal view of these advances, suggest a series of important future questions about synapses, and discuss ideas about how best to achieve further progress in the field. | 18,995,821 |
The fast-growing business of SUMO chains. | Like ubiquitin itself, the small ubiquitin-related modifier SUMO can form polymeric chains on many of its targets. Recent analyses have provided evidence for a number of distinct biological functions of the poly-SUMO signal. | 18,995,828 |
FANCM and FAAP24 function in ATR-mediated checkpoint signaling independently of the Fanconi anemia core complex. | The Fanconi anemia (FA) pathway is implicated in DNA repair and cancer predisposition. Central to this pathway is the FA core complex, which is targeted to chromatin by FANCM and FAAP24 following replication stress. Here we show that FANCM and FAAP24 interact with the checkpoint protein HCLK2 independently of the FA core complex. In addition to defects in FA pathway activation, downregulation of FANCM or FAAP24 also compromises ATR/Chk1-mediated checkpoint signaling, leading to defective Chk1, p53, and FANCE phosphorylation; 53BP1 focus formation; and Cdc25A degradation. As a result, FANCM and FAAP24 deficiency results in increased endogenous DNA damage and a failure to efficiently invoke cell-cycle checkpoint responses. Moreover, we find that the DNA translocase activity of FANCM, which is dispensable for FA pathway activation, is required for its role in ATR/Chk1 signaling. Our data suggest that DNA damage recognition and remodeling activities of FANCM and FAAP24 cooperate with ATR/Chk1 to promote efficient activation of DNA damage checkpoints. | 18,995,830 |
Structure and substrate recruitment of the human spindle checkpoint kinase Bub1. | In mitosis, the spindle checkpoint detects a single unattached kinetochore, inhibits the anaphase-promoting complex or cyclosome (APC/C), and prevents premature sister chromatid separation. The checkpoint kinase Bub1 contributes to checkpoint sensitivity through phosphorylating the APC/C activator, Cdc20, and inhibiting APC/C catalytically. We report here the crystal structure of the kinase domain of Bub1, revealing the requirement of an N-terminal extension for its kinase activity. Though the activation segment of Bub1 is ordered and has structural features indicative of active kinases, the C-terminal portion of this segment sterically restricts substrate access to the active site. Bub1 uses docking motifs, so-called KEN boxes, outside its kinase domain to recruit Cdc20, one of two known KEN box receptors. The KEN boxes of Bub1 are required for the spindle checkpoint in human cells. Therefore, its unusual active-site conformation and mode of substrate recruitment suggest that Bub1 has an exquisitely tuned specificity for Cdc20. | 18,995,837 |
Why did the frequency of palatine torus increase in the ancient Anatolian populations? | The frequency of the palatine torus varies in various populations from different regions of the world. In this study, the change of frequency of palatine torus is examined using 387 skulls from 12 different ancient Anatolian populations in various periods ranging from the Early Bronze Age to the first quarter of the 20th century. While the frequency of palatine torus is 45% in the Early Bronze Age, this ratio steadily increases to 87% in the Ottoman Period and finally declines to 40% during the recent period. It was determined that the increase in the frequency of the palatine torus is statistically significant across different periods from the Early Bronze Age until the 20th century. Constituting a passageway between Asia and Europe and being located on the crossroads of the most important trade route of the Medieval Period, the Silk Road, Anatolia is known to have been subjected to recurring invasions and migrations since the 11th century A.D. Therefore, it is possible to say that, with the introduction of the Mongoloid influence in Anatolia, genetic flow has had a significant role in the observed increase in the frequency of this trait. | 18,995,851 |
Acute phase protein levels in pregnancy and oestrus cycle in bitches. | The purpose of this study was to evaluate the acute phase protein (serum amyloid A, C-reactive protein, haptoglobin, ceruloplasmin and fibrinogen) profiles in pregnant dogs as well as bitches at various stages of the estrus cycle and to verify possible relationship(s) among the APPs profile and hormonal status. A total of 60 bitches of various breeds were enrolled. The animals were divided into six groups. B-mode ultrasonographic scanner (concept M/C) was used for pregnancy diagnosis, involving the first and second halves of pregnancy. Proestrus, estrus, diestrus and anestrus stages of sexual cycles were differentiated by use of vaginal cytology and blood progesterone and estradiol 17-beta levels. Serum C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin, ceruloplasmin and fibrinogen levels were determined. No statistically significant differences were observed between the groups with regard to the serum SAA and CRP concentrations. Haptoglobin, ceruloplasmin and fibrinogen concentrations were elevated in pregnant dogs compared to non-pregnant groups', independently from the pregnancy stage. No statistically significant differences in acute phase protein concentrations in dogs at various stages of estrus could be detected. Results of this study indicated that ceruloplasmin and fibrinogen levels may have potential importance in the diagnosis of pregnancy, and acute phase proteins may be used for monitoring the health status of the pregnant dogs. | 18,995,874 |
Impacts of weathered tire debris on the development of Rana sylvatica larvae. | Highway runoff has the potential to negatively impact receiving systems including stormwater retention ponds where highway particulate matter can accumulate following runoff events. Tire wear particles, which contain about 1% Zn by mass, make up approximately one-third of the vehicle derived particulates in highway runoff and therefore may serve as a stressor to organisms utilizing retention ponds as habitat. In this study, we focused on the potential contribution of tire debris to Zn accumulation by Rana sylvatica larvae and possible lethal or sublethal impacts resulting from exposure to weathered tire debris during development. Eggs and larvae were exposed to aged sediments (containing either ZnCl2 or tire particulate matter, both providing nominal concentrations of 1000 mg Zn kg(-1)) through metamorphosis. Water column Zn was elevated in both the ZnCl2 and tire treatments relative to the control treatment, indicating that aging allowed Zn leaching from tire debris to occur. Tissue Zn was also elevated for the ZnCl2 and tire treatments indicating that Zn in the treatments was available for uptake by the amphibians. Exposure to both ZnCl2 and tire treatments increased the time for larvae to complete metamorphosis in comparison with controls. We also observed that the longer the organisms took to complete metamorphosis, the smaller their mass at metamorphosis. Our results indicate that Zn leached from aged tire debris is bioavailable to developing R. sylvatica larvae and that exposure to tire debris amended sediments can result in measurable physiological outcomes to wood frogs that may influence population dynamics. | 18,995,883 |
Synergistic cytotoxicity of interferonalpha-2b and interleukin-2 in combination with PBMC against ovarian cancer: development of an experimental model for cellular therapy. | Current therapies for ovarian cancer (OC) patients have a modest impact on long-term survival justifying the need for novel treatment strategies. We developed in vitro and in vivo systems to test the effects of cytokines in combination with peripheral blood mononuclear cells (PBMC) on OC cells. Two OC cell-lines were transfected with a plasmid encoding Red Fluorescent Protein (SKOV3-RFP and CAR3-RFP). Proliferation of these lines in the presence of cytokines alone and in combination was assayed. Cytotoxicity of SKOV3-RFP cells mediated by PBMC and cytokines was determined by lactate dehydrogenase release. Mice were injected intraperitoneally (IP) with SKOV3-RFP cells; solid tumor and ascitic fluid were collected, analyzed, and cell lines were established. Tumor-derived cell lines were re-injected to produce a more tumorigenic line. IFNalpha-2b showed an inhibitory effect on OC cell proliferation. The remaining cytokines, either alone or in combination, showed no significant effect. PBMC in combination with IL-2 showed clear dose-dependent cytotoxicity against SKOV3-RFP. IFNalpha-2b had a synergistic effect with IL-2 and PBMC increasing the cytotoxicity by an average of 20%. Using an animal model, SKOV3-RFP cells continue to express RFP when harvested from the peritoneum and are more tumorigenic when re-injected into mice. These observations justify the use of IL-2, IFNalpha-2b, and PBMC in a xenograph animal model of OC to determine if combination cytokine and cellular therapy has an anti-tumor effect in vivo. This approach may prove useful as an in vivo system of IP cytokines administered in combination with cellular therapy. | 18,995,891 |
Improved quality of sex-sorted sperm: a prerequisite for wider commercial application. | To date the only successful method to sort sperm into X- and Y-chromosome-bearing populations is the Beltsville Sperm Sexing Technology. Fertility results continue to be variable even though the technology has been used in a commercial setting for nearly a decade. This is at least partly due to the reduced lifespan of sperm after sorting and freezing. Several technical and biological factors are responsible for this problem. Furthermore, to meet economic demands, only 10-15% of the number of sperm (compared to unsexed semen) are loaded in each straw, further limiting the chances for fertilization. A new protocol for preservation of bull sperm, utilizing Sexcess shows promise in extending the lifespan of sorted bull sperm. Motility and acrosome integrity are significantly increased using Sexcess. Conception rates achieved with heifers for those bulls tested with Sexcess and using a standard AI regime give results that do not differ from results achieved using regular AI. In addition to the improvements of the sorting technology itself, we recommend a thorough pre-selection of bulls. A reliable prediction method to determine whether a bull is suitable for a sex-sorting program still does not exist. Such a test is needed, especially for "custom sorting" programs. Currently, test sorts are the only means of obtaining information about the sorting efficiency of semen from a particular bull. | 18,995,893 |
Human fetal membranes: a source of stem cells for tissue regeneration and repair? | The ability of stem cells to differentiate into multiple cell lineages has ushered in exciting possibilities for stem cell based therapies that would be used to regenerate and repair damaged tissues and organs. Stem cells isolated from the embryo, fetus, adult and also the umbilical cord and placenta are being widely tested. Recent studies show that human fetal membranes also harbour cells with stem cell like properties. The amnion and chorion contain stromal cells that display characteristics and differentiation potential similar to that of adult, bone marrow derived mesenchymal stem cells. Amniotic epithelial cells share some of the features of pluripotent embryonic stem cells and multipotent mesenchymal stem cells and differentiate into multiple cell lineages in vitro. Amniotic epithelial cells also produce numerous substances that could augment tissue regeneration and repair. This review will focus on the stem cell like properties of stromal and epithelial cells derived from human fetal membranes and their potential use in stem cell based therapies. | 18,995,896 |
Second myeloablative allogeneic stem cell transplantation (SCT) using cord blood for leukemia relapsed after initial allogeneic SCT. | There are many reports of second allogeneic stem cell transplantation (allo-SCT) using cord blood (CB) for graft failure after initial allo-SCT. However, the efficacy of second allo-SCT using CB for patients with leukemia relapsed after initial allo-SCT is unknown. We report the results of second allo-SCT using CB in seven adult patients with leukemia relapsed after initial allo-SCT. All patients received a myeloablative conditioning regimen including oral busulfan 16 mg/kg, intravenously fludarabine 100mg/m(2) and cyclophosphamide 120 mg/kg. All but one patient had myeloid reconstitution and four patients remain alive at between 4 and 40 months after second SCT. We conclude that second myeloablative allo-SCT using CB may be feasible in selected patients with the relatively younger age, less organ damage and longer time interval between first and second allo-SCT. | 18,995,897 |
Quantitative structure-property relationship studies for direct photolysis rate constants and quantum yields of polybrominated diphenyl ethers in hexane and methanol. | The direct photolysis of 18 individual polybrominated diphenyl ethers (PBDEs) substituted with 1-7 bromine atoms was investigated in hexane and methanol under UV irradiation. Based on the determined photolysis rate constants (k(p)) and calculated quantum yields (Phi), four quantitative structure-property relationship (QSPR) models were developed by partial least squares (PLS) method and 20 fundamental molecular structural descriptors. The fitting results showed that all of four QSPR models had good predictability and correlations between observed and predicted photolysis data were significant. The predominant molecular descriptors governing photolysis rate constants of PBDEs in hexane were Mw; Sm; qBr; and qBr+], while in methanol the significant variables were alpha, TE, M(w) and S(m). In terms of the QSPR models for quantum yields of PBDEs in hexane and methanol, the governing molecular descriptors were almost the same. Molecular weight (M(w)) and three atomic charge descriptors (qBr, qH, qBr) were all presented in the four QSPR models, implying that photolysis rate constants and quantum yields were affected by the bromination degree and substitution pattern of PBDE molecules. | 18,995,905 |
Mutagenicity and genotoxicity of coal fly ash water leachate. | Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals-sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significant (P<0.05) concentration-dependent increases in DNA damage in whole blood cells, lymphocytes, and in Nicotiana plants. The comet parameters show increases in tail DNA percentage (%), tail length (mum), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations. | 18,995,907 |
Health risk by inhalation of PM2.5 in the metropolitan zone of the City of Mexico. | The study assessed the risk to the health of the inhabitants of the metropolitan zone of the City of Mexico posed by the chemical elemental contamination present in PM(2.5) particles. PIXE (particle induced X-ray emission) analysis of particles identified 18 elements, thereby achieving an elemental characterization. In order to calculate the risk posed by each element, the dose of elemental exposure was considered in relation to the corresponding reference dose. This gave an elemental risk of less than 1 for the three age groups; however, when the additive risk is considered for each age group a value exceeding 1 is obtained. Hence, although no individual element represents a public health risk, a consideration of the total risk for each of the age groups shows that members of the population are at high risk of contracting any one of the diseases that can be caused by the elements present in PM(2.5). | 18,995,908 |
Water Babies: an evolutionary parable. | The nineteenth-century Anglican theologian Charles Kingsley was immediately impressed by Darwin's Origin of Species. Whilst many in Victorian Britain reacted against the idea of natural selection, Kingsley saw in the contingency of selection a divinely ordained imperative for human endeavour, not least the pursuit of scientific knowledge. Here, Kingsley believed, was a crucial insight into the seemingly indifferent laws of nature, one that humankind could use to elevate themselves to ever-greater heights. Kingsley chose to teach these lessons about the moral nature of evolution through 'Water Babies', one of the most charming and enduring of children's fairy tales. | 18,995,909 |
Combined hamartoma of the retina and retinal pigment epithelium in 77 consecutive patients visual outcome based on macular versus extramacular tumor location. | To evaluate visual outcome of eyes with combined hamartoma of the retina and retinal pigment epithelium (RPE). Noncomparative case series. Seventy-nine eyes of 77 patients. Retrospective chart review. Visual outcome. The presenting symptoms were decreased vision (n = 32; 40%), strabismus (n = 22; 28%), both (n = 3; 4%), irritation (n = 4; 5%), and none (n = 18; 23%). The tumors had the following characteristics: a mean diameter of 7.6 mm, a mean thickness of 1.9 mm, round (n = 52; 66%) or curvilinear (n = 27; 34%) configuration, and other features including intralesional corkscrew vessels (n = 51; 65%), feeding straight vessels (n = 50; 63%), retinal traction (n = 64; 81%), fibrosis/gliosis (n = 36; 46%), and exudation (n = 10; 13%). Referring diagnosis was unknown (n = 40; 51%) or incorrect (n = 19; 24%) as retinoblastoma (n = 4), astrocytoma (n = 1), toxocariasis (n = 2), choroidal nevus (n = 5), melanoma (n = 6), and hemangioma (n = 1). The mean initial visual acuity by logarithm of the minimum angle of resolution (Snellen) for macular (n = 29) versus extramacular (n = 28) tumors was 1.2 (20/320) versus 0.61 (20/80) and at 4 years was 1.72 (20/800) versus 0.79 (20/125). Visual acuity loss of >or=3 Snellen lines was 60% versus 13%. By univariate analysis, the most important factors predictive of poor visual acuity included macular location and clock hour meridian of the tumor. Combined hamartoma of the retina and RPE can cause profound visual acuity loss, particularly with macular tumors. The authors have no proprietary or commercial interest in any materials discussed in this article. | 18,995,912 |
Association between circadian rhythm of blood pressure and glucose tolerance status in normotensive, non-diabetic subjects. | To examine whether circadian rhythm of blood pressure (BP) is associated with glucose tolerance status in normotensive, non-diabetic subjects. A cross-sectional study recruited normotensive and non-diabetic subjects, aged 35-79 years. A 75 g oral glucose tolerance test (OGTT) and 24-h ambulatory blood pressure monitoring (24-h ABPM) were performed. Among 31 impaired glucose tolerance (IGT) and 36 normal glucose tolerance (NGT) study subjects, the mean (+/-S.D.) diurnal-nocturnal differences of average systolic BP (SBP) were 7.1+/-6.9 and 9.9+/-6.2 mmHg, respectively (p=0.086). In a linear mixed-effects regression model, however, taking each measurement of BP as the outcome, nighttime reduction of SBP in the IGT group was 7.19 mmHg, which was significantly smaller compared to a reduction of 9.80 mmHg in the NGT group (p-value for IGT: nighttime interaction=0.0014). The prevalence of non-dipping BP pattern was 77.4% in the IGT group which was significantly higher than 52.8% of the NGT group (p=0.036). Logistic regression revealed a significant effect of IGT for predicting non-dipping pattern with an adjusted odds ratio of 3.71 (95% CI: 1.09, 12.66, p=0.029). Among normotensive, non-diabetic subjects, the decreased nocturnal BP reduction was associated with impaired glucose tolerance status. | 18,995,921 |
Long-term effects of lead poisoning on bone mineralization in vultures exposed to ammunition sources. | Long-lived species are particularly susceptible to bioaccumulation of lead in bone tissues. In this paper we gain insights into the sublethal effects of lead contamination on Egyptian vultures (Neophron percnopterus). Our approach was done on the comparison of two populations (Canary Islands and Iberian Peninsula) differing in exposures to the ingestion of lead ammunition. Blood lead levels were higher in the island population (Canary Islands range: 5.10-1780 microg L(-1) n=137; Iberian Peninsula range: 5.60-217.30 microg L(-1) n=32) showing clear seasonal trends, peaking during the hunting season. Moreover, males were more susceptible to lead accumulation than females. Bone lead concentration increased with age, reflecting a bioaccumulation effect. The bone composition was significatively altered by this contaminant: the mineralization degree decreased as lead concentration levels increased. These results demonstrate the existence of long-term effects of lead poisoning, which may be of importance in the declines of threatened populations of long-lived species exposed to this contaminant. | 18,995,938 |
Neighborhood effects on birthweight: an exploration of psychosocial and behavioral pathways in Baltimore, 1995--1996. | Neighborhood characteristics have been proposed to influence birth outcomes through psychosocial and behavioral pathways, yet empirical evidence is lacking. Using data from an urban, low-income sample, this study examined the impact of the neighborhood environment on birthweight and evaluated mediation by psychosocial and behavioral factors. The sample included 726 women who delivered a live birth at Johns Hopkins Hospital in Baltimore, Maryland, USA between 1995 and 1996. Census-tract data were used to create a principal component index of neighborhood risk based on racial and economic stratification (% Black, % poverty), social disorder (violent crime rate), and physical deterioration (% boarded-up housing) (alpha=0.82). Information on sociodemographic, psychosocial, and behavioral factors was gathered from a postpartum interview and medical records. Random intercept multilevel models were used to estimate neighborhood effects and assess potential mediation. Controlling for sociodemographic characteristics, a standard deviation increase in neighborhood risk conferred a 76g birthweight decrement. This represents an approximate 300g difference between the best and worst neighborhoods. Although stress (daily hassles), perceived locus-of-control, and social support were related to birthweight, their adjustment reduced the neighborhood coefficient by only 12%. In contrast, the neighborhood effect was reduced by an additional 30% and was no longer statistically significant after adjustment for the behavioral factors of smoking, drug use, and delayed prenatal care. These findings suggest that neighborhood factors may influence birthweight by shaping maternal behavioral risks. Thus, neighborhood level interventions should be considered to address multiple maternal and infant health risks. Future studies should examine more direct measures of neighborhood stress, such as perceived neighborhood disorder, and evaluate alternative mechanisms by which neighborhood factors influence behavior (e.g., social norms and access to goods and services). | 18,995,941 |
Accuracy of CA 125 in the diagnosis of ovarian tumors: a quantitative systematic review. | A quantitative systematic review was performed to estimate the accuracy of CA 125 assay in the diagnosis of ovarian tumors. Studies that evaluated CA 125 levels for the diagnosis of ovarian tumors and compared them with paraffin-embedded sections as the diagnostic standard were included. Seventeen studies were analyzed, which included 2374 women. The pooled sensitivity for the diagnosis of borderline tumors or ovarian cancer was 0.80 (I.C. 95% 0.76-0.82) and the specificity was 0.75 (I.C. 95% 0.73-0.77). The diagnostic odds ratio for ovarian cancer and borderline lesions vs. benign lesions was 21.2 (95% C.I., 12-37). Summary receiver operating characteristic curves were constructed due to heterogeneity in the diagnostic odds ratio. For malignant and borderline ovarian tumors vs. benign lesions the area under the curve was 0.8877. A CA 125 level of >or= 35 U/ml is a useful preoperative test for predicting the benign or malignant nature of pelvic masses. The accuracy of CA 125 in the diagnosis of ovarian tumors is high and very important in helping the surgeon to decide what kind of surgery should be performed. | 18,995,946 |
Electron microscopy localization and characterization of functionalized composite organic-inorganic SERS nanoparticles on leukemia cells. | We demonstrate the use of electron microscopy as a powerful characterization tool to identify and locate antibody-conjugated composite organic-inorganic nanoparticle (COINs) surface enhanced Raman scattering (SERS) nanoparticles on cells. U937 leukemia cells labeled with antibody CD54-conjugated COINs were characterized in their native, hydrated state using wet scanning electron microscopy (SEM) and in their dehydrated state using high-resolution SEM. In both cases, the backscattered electron (BSE) detector was used to detect and identify the silver constituents in COINs due to its high sensitivity to atomic number variations within a specimen. The imaging and analytical capabilities in the SEM were further complemented by higher resolution transmission electron microscopy (TEM) images and scanning Auger electron spectroscopy (AES) data to give reliable and high-resolution information about nanoparticles and their binding to cell surface antigens. | 18,995,965 |
C2H2 interaction with Ni nanocrystals: towards a better understanding of carbon nanotubes nucleation in CVD synthesis. | We present a study of the early stages of carbon nanotubes nucleation in CVD synthesis by combining field ion/electron emission microscopy (FIM/FEM) and atom-probe investigation (AP) of the nickel-carbon interaction. Acetylene decomposition on Ni tips at 873K is observed to induce additional step formation on an initially facetted (polyhedral) crystal. Carbon-enriched steps are then observed to act as preferential nucleation centers of graphene sheets formation. Atom-probe experiments reveal C(2) and C(3) species and frequency dependent studies demonstrate that the origin of these species is different from C(1). Experiments provide clear evidence for the crucial role of carbon-enriched steps as nucleation sites of graphene sheets on the Ni surface. | 18,995,966 |
A follow-up investigation on the quality of medical documents from examinations of Basque incommunicado detainees: the role of the medical doctors and national and international authorities in the prevention of ill-treatment and torture. | According to the United Nations and the European Committee for the Prevention of Torture (CPT), torture and ill-treatment continues to be a problem during incommunicado detentions in Spain. CPT has visited Spain and published recommendations for improvements of preventive medical examinations. However, no scientific assessment of the impact of such recommendations exists. The objectives of this study were to assess the quality of documents from preventive medical examinations and the prevalence of alleged ill-treatment and compare findings with similar data from a previous study. Documents issued by state employed doctors describing medical examination of Basques held incommunicado during 2000-2005 were reviewed. The analysis covered allegations of ill-treatment and existence and quality of information essential for medical appraisal of allegations of ill-treatment. The material was collected by a non-governmental organisation. Of 425 documents concerning 118 persons, 85% had no formal structure and the format recommended by CPT was never used. None of 127 documents, concerning 70 persons with allegations of ill-treatment had an overall conclusion on the likelihood of ill-treatment. Twelve to 68% of necessary data were totally missing, and only 13-38% of existing information was sufficient. There was significant variation between the reporting of individual doctors, but in general the quality was unacceptable, although somewhat higher than in the previous study. The prevalence of allegations of ill-treatment was as high as previously. There were more reports of psychological ill-treatment and procedures of forced physical exhaustion, but fewer reports of beatings. In conclusion, there was no indication that the conditions of incommunicado detainees have improved substantially over the past 15 years and the standard of medical reporting was unacceptable. The Spanish authorities should give clear objectives and guidelines for medical examinations of detainees. An independent forensic specialist with the overall academic responsibility for preventive medical examinations of detainees should be employed to supervise state employed doctors. The present article shows the necessity for harmonization of medical practice in documentation of torture. | 18,995,973 |
[Childhood medulloblastoma]. | Medulloblastoma is one of the most common malignant childhood brain tumors. It is a primitive neuroectodermal tumor (PNET) and predominantly arises in the cerebellum and 4th ventricle. Most cases of medulloblastoma are sporadic, but some predisposition syndromes are known, such as SUFU and Gorlin syndromes. Most often intracranial hypertension reveals the disease typically with headache and vomiting. However, the frequent atypical presentation should not delay neuroradiological investigations. Brain and spinal MRI can establish the diagnosis of posterior fossa tumor and define the extent of the disease. CSF study completes the staging. Histologic examination of the tumor confirms the diagnosis of medulloblastoma. Patients are classified into 2 risk groups: standard-risk medulloblastoma, defined by nonmetastatic disease treated by total or subtotal tumor resection; and high-risk patients who have disseminated disease and/or residual disease. Tumor molecular genetic findings allow the use of emerging prognostic factors and may ultimately contribute to the development of targeted therapy. Current treatment in the oldest children combines surgical resection followed by radiotherapy and chemotherapy. The aim of recent studies was to increase survival and decrease sequelae by reducing CSI in older children with standard risk medulloblastoma. Treatment in younger patients is as much as possible restricted to surgery and chemotherapy. However, long-term sequelae after treatment for medulloblastoma remain frequent and the detection and treatment of those sequelae is an essential part of the follow-up of the patients. | 18,995,998 |
Visual feedback training improves postural adjustments associated with moving obstacle avoidance in elderly women. | The study examined the impact of visually guided weight shifting (WS) practice on the postural adjustments evoked by elderly women when avoiding collision with a moving obstacle while standing. Fifty-six healthy elderly women (70.9+/-5.7 years, 87.5+/-9.6 kg) were randomly assigned into one of three groups: a group that completed 12 sessions (25 min, 3s/week) of WS practice in the Anterior/Posterior direction (A/P group, n=20), a group that performed the same practice in the medio/lateral direction (M/L group, n=20) and a control group (n=16). Pre- and post-training, participants were tested in a moving obstacle avoidance task. As a result of practice, postural response onset shifted closer to the time of collision with the obstacle. Side-to-side WS resulted in a reduction of the M/L sway amplitude and an increase of the trunk's velocity during avoidance. It is concluded that visually guided WS practice enhances elderly's ability for on-line visuo-motor processing when avoiding collision eliminating reliance on anticipatory scaling. Specifying the direction of WS seems to be critical for optimizing the transfer of training adaptations. | 18,996,012 |
C-2-aryl O-substituted HI-236 derivatives as non-nucleoside HIV-1 reverse-transcriptase inhibitors. | Several novel thiourea derivatives of the NNRTI HI-236 substituted at the C-2 oxygen of the phenyl ring have been synthesized and evaluated for their inhibitory activity against HIV-1 (IIIB) replication in MT-2 cell cultures. The compounds were synthesized in order to fine-tune the activity of HI-236 as well as to gain insight into spatial characteristics in the pocket pertaining to the positional choice of tether in the design of [NRTI]-tether-[HI-236] bifunctional inhibitors. Two of the thiourea derivatives bearing a butynyl (6c) or hydroxyethyl tether (6n) were endowed with improved anti-HIV activity compared to HI-236. NNRTI activity was confirmed by a cell-free RT assay on six of the derivatives in which 6c returned an IC(50) of 3.8 nM compared to 28 nM for HI-236, establishing it as an improved lead for HI-236. The structure-activity profile is discussed in terms of potential interactions in the NNRTI pocket as suggested by a docking model using AutoDock, which have a bearing on the bifunctional drug design. | 18,996,020 |
Initial experience with 'inverted U' staged buccal mucosa graft (bracka) for hypospadias repair. | To describe a modification of the Bracka procedure ('inverted U'), used to enlarge the graft and diminish the risk of graft contracture compromising the subsequent urethral reconstruction. Inverted U Bracka procedure was performed in 10 children in whom previous hypospadias correction had failed. The surgical steps are identical to the original Bracka procedure. The only modification is reconfiguration to enlarge the graft. Significant contraction of the graft was not seen in any patient and the second stage was performed uneventfully. After the second surgery there were two complications: one fistula and one wound infection. In this preliminary study, the modification avoided significant contracture of the graft giving a more predictable size of the neourethra for the second-stage procedure. An amplified series is necessary to confirm this initial result. | 18,996,051 |
REMOVED: In defense of King et al.: the validity of manual examination in assessing patients with neck pain. | This article has been removed consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause. | 18,996,053 |
The use of proteome similarity for the qualitative and quantitative profiling of reperfused myocardium. | An LC-MS-based approach is presented for the identification and quantification of proteins from unsequenced organisms. The method relies on the preservation of homology across species and the similarity in detection characteristics of proteomes in general. Species related proteomes share similarity that progresses from the amino acid frequency distribution to the complete amino sequence of matured proteins. Moreover, the comparative analysis between theoretical and experimental proteome distributions can be used as a measure for the correctness of detection and identification obtained through LC-MS-based schemes. Presented are means to the identification and quantification of rabbit myocardium proteins, immediately after inducing cardiac arrest, using a data-independent LC-MS acquisition strategy. The employed method of acquisition affords accurate mass information on both the precursor and associated product ions, whilst preserving and recording the intensities of the ions. The latter facilitates label-free quantification. The experimental ion density observations obtained for the rabbit sub proteome were found to share great similarity with five other mammalian samples, including human heart, human breast tissue, human plasma, rat liver and a mouse cell line. Redundant, species-homologues peptide identifications from other mammalian organisms were used for initial protein identification, which were complemented with peptide identifications of translated gene sequences. The feasibility and accuracy of label-free quantification of the identified peptides and proteins utilizing above mentioned strategy is demonstrated for selected cardiac rabbit proteins. | 18,996,061 |
Influence of clotting time on the protein composition of serum samples based on LC-MS data. | Many large, disease-related biobanks of serum samples have been established prior to the widespread use of proteomics in biomarker research. These biobanks may contain relevant information about the disease process, response to therapy or patient classifications especially with respect to long-term follow-up that is otherwise very difficult to obtain based on newly initiated studies, particularly in the case of slowly developing diseases. An important parameter that may influence the composition of serum but that is often not exactly known is clotting time. We therefore investigated the influence of clotting time on the protein and peptide composition of serum by label-free and stable-isotope labeling techniques. The label-free analysis of trypsin-digested serum showed that the overall pattern of LC-MS data is not affected by clotting times varying from 2 to 8h. However, univariate and multivariate statistical analyses revealed that proteins that are directly involved in blood clot formation, such as the clotting-derived fibrinopeptides, change significantly. This is most easily detected in the supernatant of acid-precipitated, immunodepleted serum. Stable-isotope labeling techniques show that truncated or phosphorylated forms of fibrinopeptides A and B increase or decrease depending on clotting time. These patterns can be easily recognized and should be taken into consideration when analyzing LC-MS data using serum sample collections of which the clotting time is not known. Next to the fibrinopeptides, leucine-rich alpha-2-glycoprotein (P02750) was shown to be consistently decreased in samples with clotting times of more than 1h. For prospective studies, we recommend to let blood clot for at least 2h at room temperature using glass tubes with a separation gel and micronized silica to accelerate blood clotting. | 18,996,063 |
What determines the need to morcellate the uterus during total laparoscopic hysterectomy? | To identify factors associated with the need to perform uterine morcellation during total laparoscopic hysterectomy (TLH). A secondary aim was to establish new cut-offs based on uterine weight for the probability of morcellation. Prospective observational study (Canadian Task Force Classification II-2). Tertiary referral laparoscopic unit. All women scheduled to undergo TLH in the study period were included. Age, parity, operating time, estimated blood loss, and final uterine weight at histology were recorded. Logistic regression analysis was performed to determine the factors associated with the need to perform uterine morcellation at the time of TLH. Multiple imputation (MI) was used to impute missing values. A total of 112 consecutive women underwent TLH and were included in the final analysis. In all, 56 (50%) of 112 women underwent TLH without morcellation (i.e., it was possible to deliver the uterine specimen vaginally) and 56 (50%) of 112 women underwent TLH with morcellation (i.e., it was not possible to deliver the uterine specimen vaginally and, therefore, morcellation was performed). Median age in each group was 45 and 46 years, respectively. Sixteen (70%) of 23 nulliparous women underwent morcellation compared with 40 (45%) of 89 parous women. Multivariable logistic regression analysis revealed that nulliparity (OR = 6.45, 95% CI = 1.74-23.9) and uterine weight (OR/100-g increase = 4.97, 95% CI = 2.13-11.6) increased the odds of morcellation. All 20 women with a uterine weight of at least 350 g required morcellation. Based on the MI analysis results, uterine weight was at least 350 g in 1 of 5 patients, with 99.5% of the women having uterine weight of 350 g or more that required morcellation. Nulliparity and increasing uterine weight are associated with the need to perform uterine morcellation in TLH. Studies are needed to find a reliable method for estimating uterine weight preoperatively. | 18,996,059 |
Capability of human umbilical cord blood progenitor-derived endothelial cells to form an efficient lining on a polyester vascular graft in vitro. | One of the goals of vascular tissue engineering is to create functional conduits for small-diameter bypass grafting. The present biocompatibility study was undertaken to check the ability of cord blood progenitor-derived endothelial cells (PDECs) to take the place of endothelial cells in vascular tissue engineering. After isolation, culture and characterization of endothelial progenitor cells, the following parameters were explored, with a commercial knitted polyester prosthesis (Polymaille C, Laboratoires Pérouse, France) impregnated with collagen: cell adhesion and proliferation, colonization, cell retention on exposure to flow, and the ability of PDECs to be regulated by arterial shear stress via mRNA levels. PDECs were able to adhere to commercial collagen-coated vascular grafts in serum-free conditions, and were maintained but did not proliferate when seeded at 2.0 x 10(5) cm(-2). Cellularized conduits were analyzed by histology and histochemical staining, demonstrating collagen impregnation and the endothelial characteristics of the colonizing cells. Thirty-six hours after cell seeding the grafts were maintained for 6 h of either static conditions (controls) or application of pulsatile laminar shear stress, which restored the integrity of the monolayer. Finally, quantitative real-time RT-PCR analysis performed at 4 and 8 h from cells lining grafts showed that MMP1 mRNA only was increased at 4h whereas vWF, VE-cadherin and KDR were not significantly modified at 4 and 8 h. Our results show that human cord blood PDECs are capable of forming an efficient lining and to withstand shear stress. | 18,996,071 |
Surgical debridement, vacuum therapy and pectoralis plasty in poststernotomy mediastinitis. | In cardiac surgery poststernotomy mediastinitis continues to be a serious cause of morbidity and mortality. We report our experience with vacuum-assisted closure (VAC) therapy followed by reconstruction with M. pectoralis muscle flaps as treatment for deep sternal wound infections. Our group performed a retrospective analysis of 3630 consecutive cardiac surgical patients using median sternotomy from 11/2004 to 11/2007. After removing sternal wires, necrotic debris and potentially infective material, restabilisation of the sternum was performed and VAC therapy was employed. Wound closure and subsequent reconstruction were performed using a bilateral pectoralis muscle plasty. Of the analysed patients 16 female and 29 male patients suffered from deep sternal wound infections and were treated with VAC. The most common risk factors were diabetes mellitus odds ratio (OR 3.5), chronic obstructive pulmonary disease (COPD) (OR 2.9), use of bilateral mammarian artery (OR 2.0) and obesity (1.8). The median age of patients with deep sternal infections was similar to control patients. Staphylococcus epidermis was the most common pathogen (37.8%) followed by Enterococcus faecilis (22.2%) and Staphylococcus aureus (17.8). In 22.2% no pathogen could be detected. The 30 day mortality was 0%, the in-hospital mortality was 15.6%. The results of our studies demonstrate that vacuum therapy in conjunction with early and aggressive debridement is an effective strategy for treating poststernotomy mediastinitis. We consider pectoralis major muscle flap reconstruction as a safe technique and regard it as the primary choice for wound closure in poststernotomy mediastinitis. | 18,996,074 |
Premature differentiation and aberrant movement of pituitary cells lacking both Hes1 and Prop1. | In the pituitary, the transition from proliferating progenitor cell into differentiated hormone producing cell is carefully regulated in a time-dependent and spatially-restricted manner. We report that two targets of Notch signaling, Hes1 and Prop1, are needed to maintain progenitors within Rathke's pouch and for the restriction of differentiated cells to the ventral pituitary. We observed ACTH and alphaGSU producing cells that had prematurely differentiated within Rathke's pouch along with correlated ectopic expression of Mash1 only when both Prop1 and Hes1 were lost. We also discovered that downregulation of N-cadherin expression in cells as they transition from Rathke's pouch to the anterior lobe appears to be essential for their movement. In the Prop1 mutant, cells are trapped in Rathke's pouch and N-cadherin expression remains high. Also, Slug, a marker of epithelial-to-mesenchymal transition, is absent in the dorsal anterior lobe. When Hes1 is lost in the Prop1 mutant, N-cadherin is downregulated and cells are able to exit Rathke's pouch but have lost their migrational cues and form ectopic foci surrounding Rathke's pouch. Our data reveal important overlapping functions of Hes1 and Prop1 in cell differentiation and movement that are critical for pituitary organogenesis. | 18,996,108 |
WITHDRAWN: Gastroenterology Turns 65. | The publisher regrets that this article is an accidental duplication of an article that has already been published, doi:10.1053/j.gastro.2008.10.040. The duplicate article has therefore been withdrawn. | 18,996,121 |
Redox properties of the A-domain of the HMGB1 protein. | The High Mobility Group B1 (HMGB1) protein plays important roles in both intracellular (reductive) and extracellular (oxidative) environments. We have carried out quantitative investigations of the redox chemistry involving Cys22 and Cys44 of the HMGB1 A-domain, which form an intramolecular disulfide bond. Using NMR spectroscopy, we analyzed the real-time kinetics of the redox reactions for the A-domain in glutathione and thioredoxin systems, and also determined the standard redox potential. Thermodynamic experiments showed that the Cys22-Cys44 disulfide bond stabilizes the folded state of the protein. These data suggest that the oxidized HMGB1 may accumulate even in cells under oxidative stress. | 18,996,119 |
Beckmann reactions of steroidal spirocyclic oximes derived from the 16beta,23:23,26-diepoxy-22-oxo moiety. | The Beckmann rearrangement of the syn and anti isomers of the spirocyclic oxime derived from a 16beta,23:23,26-diepoxy-5beta-cholestan-22-one was studied. Whereas the anti isomer always follows the Beckmann fragmentation course, the syn isomer, depending on the reaction conditions, follows the normal Beckmann rearrangement course and/or the isomerization to the anti isomer followed by the fragmentation course. | 18,996,137 |
An exact steady state solution of Fisher's geometric model and other models. | Because nearly neutral substitutions are thought to contribute substantially to molecular evolution, and much of our insight about the workings of nearly neutral evolution relies on theory, solvable models of this process are of particular interest. Here, I present an analytical method for solving models of nearly neutral evolution at steady state. The steady state solution applies to any constant fitness landscape under a dynamic of successive fixations, each of which occurs on the background of the population's most recent common ancestor. Because this dynamic neglects the effects of polymorphism in the population beyond the mutant allele under consideration, the steady state solution provides a decent approximation of evolutionary dynamics when the population mutation rate is low (Nu<<1). To demonstrate the method, I apply it to two examples: Fisher's geometric model (FGM), and a simple model of molecular evolution. Since recent papers have studied the steady state behavior of FGM under this dynamic, I analyze its behavior in detail and compare the results with previous work. | 18,996,138 |
Molecular characterization of a sodium channel gene from the Silkworm Bombyx mori. | The voltage-gated sodium channel mediates the rapid rising phase of action potentials in almost all excitable cells and is a molecular target of a variety of neurotoxins including pyrethroid insecticides. Most studies have focused on the expression of sodium channel genes in the adult stage, information on other developmental stages, however, is limited. In this study, we characterized the para sodium channel orthologous gene (BmNa(v)) of the silkworm Bombyx mori, a model insect of Lepidopteran species. The BmNa(v) gene covers a 31 kb genome region and contains 36 exons. The longest ORF contained 6258 bp and encoded 2085 amino acid residues, which shares 74%, and 77% overall amino acid sequence identities with the sodium channel proteins from Drosophila melanogaster and Blattella germanica, respectively. Using high-throughput Solexa sequence technology we conducted sequence analysis of BmNa(v) cDNAs from embryos, larvae, pupae and adults of the silkworm, identified alternative splicing sites and determined the frequencies of these splicing events in four developmental stages. Three optional exons, two sets of mutually exclusive exons, and one internal spliced exon were identified. One optional exon is unique to BmNa(v), while the others are conserved in other insect sodium channel genes. Interestingly, the expression of the mutually exclusive exons is developmentally regulated. | 18,996,195 |
The future (or lack of future) of personalized prescription in psychiatry. | Rapid technological advances in genetics have created conceptual chaos regarding the genetics of drug response. Terms for differing concepts are used interchangeably: pharmacogenetics with pharmacogenomics, personalized medicine with personalized prescription. Biomarker has many definitions. The author prefers the concept of personalized prescription and uses it with implications beyond pharmacogenetics by considering all scientific information valid for prescribing medication. Genetics may not be crucial for all drugs. In this comprehensive view, clinicians must consider genetic, environmental and personal variables when prescribing medication and incorporate some basic pharmacological principles: (1) safety and efficacy, (2) pharmacokinetics and pharmacodynamics, (3) therapeutic window and prescriber's role, and (4) idiosyncratic and dose-related adverse drug reactions. Personalized prescription in the clinical environment can be expressed in two main ways: as personalized selection of the drug and as personalized dosing. The future, or lack of future, of personalized drug selection and of personalized dosing in psychiatry is reviewed. Currently, the author thinks that, in psychiatry, pharmacogenetic tests have some potential in two areas: (1) excluding some drugs for some unusual patients (HLA-B*1502 genotyping in Asians for carbamazepine), and (2) using pharmacokinetic genes for personalizing dosing in narrow therapeutic window drugs. In the short term, there is dubious potential for other pharmacogenetic tests and no potential for pharmacogenetic testing to ascertain the best drug for each patient. Personalized dosing has immediate application if one understands it as the use of our current scientific knowledge of genetic, environmental and personal variables to determine dosing; its sole requirement is well-trained psychiatrists. | 18,996,200 |
Anti-cancer effect of Cassia auriculata leaf extract in vitro through cell cycle arrest and induction of apoptosis in human breast and larynx cancer cell lines. | The in vitro anti-cancer effect of Cassia auriculata leaf extract (CALE) was evaluated in human breast adenocarcinoma MCF-7 and human larynx carcinoma Hep-2 cell lines. CALE preferentially inhibited the growth of both the cell lines in a dose-dependent manner with IC(50) values of 400 and 500 microg for MCF-7 and Hep-2 cells, respectively. The results showed the anti-cancer action is due to nuclear fragmentation and condensation, associated with the appearance of A(0) peak in cell cycle analysis that is indicative of apoptosis. In addition, CALE treated MCF-7 and Hep-2 cells had decreased expression of anti-apoptotic Bcl-2 protein and increased expression of pro-apoptotic Bax protein, eventually leading a decrease in the Bcl-2/Bax ratio. These results demonstrated that CALE inhibits the proliferation of MCF-7 and Hep-2 cells through induction of apoptosis, making CALE a candidate as new anti-cancer drug. | 18,996,213 |
Effects of testosterone therapy on muscle performance and physical function in older men with mobility limitations (The TOM Trial): design and methods. | The TOM study is the first, single-site, placebo-controlled, randomized clinical trial designed to comprehensively determine the effects of testosterone administration on muscle strength and physical function in older men with mobility limitations. A total of 252 community dwelling individuals aged 65 and older with low testosterone levels and self-reported limitations in mobility and short physical performance battery (SPPB) scores between 4 and 9 will be randomized to receive either placebo or testosterone therapy for 6 months. The primary objective is to determine whether testosterone therapy improves maximal voluntary muscle strength as quantified by the one repetition maximum. Secondary outcomes will include measures of physical function (walking, stair climbing and a lifting and lowering task), habitual physical activity and self-reported disability. The effects of testosterone on affect, fatigue and sense of well being will also be assessed. Unique aspects of the TOM Trial include selection of men with self-reported as well as objectively demonstrable functional limitations, community-based screening and recruitment, adjustment of testosterone dose to ensure serum testosterone levels in the target range while maintaining blinding, and inclusion of a range of self-reported and performance-based physical function measures as outcomes. Clinicaltrials.gov identifier: NCT00240981. | 18,996,225 |
Sources of sacroiliac region pain: insights gained from a study comparing standard intra-articular injection with a technique combining intra- and peri-articular injection. | To present evidence supporting the existence of extra-articular sources for sacroiliac region pain and to present evidence that intra-articular anesthetic blockade may underestimate the true prevalence of sacroiliac region pain. Retrospective review of 2 large case series comparing patient responses to intra-articular injection versus combined intra-articular and peri-articular injection of anesthetic and corticosteroid. Private practice chronic pain clinic set in a hospital outpatient clinic. Patients (N=120) sequentially enrolled from practice billing records. Inclusion criteria included pain in the low back below L4 and in the buttock, thigh, groin, or lower leg. If disk herniation, lumbar stenosis, or facet syndrome was previously treated with appropriately chosen injections, response to treatment had to be negative. Patients failed to respond to treatment with physical therapy. Exclusion criteria included records with an incomplete database, patients increasing pain medication use greater than 15% for pain not related to the sacroiliac region, severe psychiatric illness, and nonspecific anesthetic blockade. One hundred sixty-seven records were reviewed to obtain the 120 study subjects. Intra-articular injection was done according to the standard technique described by Fortin. Peri-articular injection was done by a slight modification of the procedure described by Yin. Percentage change in visual analog scale (VAS) pain scores at 3 weeks and 3 months postinjection; patients' self reported activities of daily living (ADLs) improvement at 3 weeks and 3 months postinjection; and percentage change in VAS pain score within 1 hour of injection. For intra-articular injection alone, the rate of positive response at 3 months was 12.50% versus 31.25% for the combined injection (P=.025). Positive response was defined as greater than 50% drop in VAS pain score or patients describing ADLs as "greatly improved." Anesthetic response rates were higher in the combined injection group (62.5% vs 42.5%; P=.037). Significant extra-articular sources of sacroiliac region pain exist. Intra-articular diagnostic blocks underestimate the prevalence of sacroiliac region pain. | 18,996,232 |
Shoulder ultrasound abnormalities, physical examination findings, and pain in manual wheelchair users with spinal cord injury. | To investigate the presence of ultrasound (US) abnormalities in manual wheelchair users with spinal cord injury (SCI) using a quantitative Ultrasound Shoulder Pathology Rating Scale (USPRS). To investigate physical examination (PE) findings using a quantitative Physical Examination of the Shoulder Scale (PESS), and to obtain data about pain and other subject characteristics such as age, years with SCI, and weight. Case series. National Veterans' Wheelchair Games 2005 and 2006. Volunteer sample of manual wheelchair users with SCI participating in the National Veterans' Wheelchair Games. Not applicable. Presence of relationships between US findings, PE findings, pain, and subject characteristics. The USPRS correlated with age, duration of SCI, and weight (all P<.01), and showed a positive trend with the total Wheelchair User's Shoulder Pain Index (WUSPI) score (r=.258, P=.073). Several US findings related to presence of PE findings for specific structures. The PESS score correlated with the WUSPI (r=.679, P<.001) and duration of SCI (P<.05). The presence of untreated shoulder pain that curtailed activity was noted in 24.5% of subjects, and this was related to increased WUSPI scores (P=.002). PE and US abnormalities are common in manual wheelchair users with SCI. The USPRS and PESS demonstrated evidence for external validity and hold promise as research tools. Untreated shoulder pain is common in manual wheelchair users with SCI, and further investigation of this pain is indicated. | 18,996,236 |
Iatrogenic femoral artery pseudoaneurysms--a review of current methods of diagnosis and treatment. | The common femoral artery is commonly used as arterial access for a wide range of radiological and cardiological procedures. Pseudoaneurysm formation is the most common arterial complication of femoral artery catheterization, and is diagnosed using colour Doppler ultrasound. Ultrasound-guided thrombin injection has replaced ultrasound-guided compression as the first-line treatment. The practicalities of thrombin injection (technique and types of thrombin available) and other treatment options are discussed. Awareness of pseudoaneurysm formation and the treatment options allows prompt diagnosis and successful treatment. | 18,996,260 |
Evaluation of multidetector computed tomography urography and ultrasonography for diagnosing bladder cancer. | To evaluate and compare the diagnostic accuracy of multidetector computed tomography urography (CTU) and ultrasonography (US) for diagnosing bladder cancer. A consecutive series of 143 patients over 40-years of age, presenting with macroscopic haematuria and without urinary tract infection underwent same-day CTU, US, and flexible cystoscopy. CTU and US were independently rated on a five-point scale for the presence of bladder cancer without knowledge of the reference standard of flexible or rigid cystoscopy and/or biopsy results. Diagnostic accuracy was assessed by receiver operating characteristic (ROC) analysis and likelihood ratios. For CTU, a rating of 5 (definitely tumour) was highly specific for bladder cancer (96.5%, 95%CI: 91.3-99%), effectively confirming diagnosis (positive likelihood ratio 25.6, 95%CI: 9.7-67.4). For US, specificity was also high (94.7%, 95%CI: 88.9-98%) with a positive likelihood ratio of 13.1 (95%CI: 5.8-29.6). Sensitivity at this rating was substantially higher for CTU (89.7%, 95%CI: 72.7-97.8%) than US (69%, 95%CI: 49.2-84.7%). Standardized partial area (Az) under the ROC curve between 95-100% specificity, representing the average sensitivity in this range, was significantly greater (0.88 versus 0.61, p<0.05) for CTU than US. The specificities of CTU and US for the diagnosis of bladder cancer were similar, but CTU was more sensitive. Although the sensitivity of CTU was not high enough to replace flexible cystoscopy in the diagnostic pathway, the high specificity enables direct referral to rigid cystoscopy, bypassing flexible cystoscopy and expediting diagnosis and treatment in those patients testing positive. | 18,996,261 |
Clinical utility of 99mTc-labeled ubiquicidin 29-41 antimicrobial peptide for the scintigraphic detection of mediastinitis after cardiac surgery. | Previous studies demonstrated that (99m)Tc-labeled-ubiquicidin 29-41 ((99m)Tc-UBI 29-41) imaging is an accurate method for detection of bacterial infections. This study was conducted to evaluate the clinical use of (99m)Tc-UBI 29-41 for detection of mediastinitis after cardiac surgery. Thirteen patients with suspected mediastinitis after cardiac surgery were included. Qualitative and semiquantitative analyses of (99m)Tc-UBI 29-41 images were performed. Mediastinitis was confirmed by bacterial culture. Qualitative analysis correctly identified the infection in 5/6 patients with mediastinitis. For observer 1, there were five true-positive results, six true-negative results, one false-positive result and one false-negative result (sensitivity: 83%, specificity: 85%, positive predictive value: 83%, negative predictive value: 85%, and overall diagnostic accuracy: 84%). For observer 2, there were five true-positive results, five true-negative results, two false-positive results and one false-negative result (sensitivity: 83%, specificity: 71%, positive predictive value: 71%, negative predictive value: 83%, and overall diagnostic accuracy: 76%). Agreement between observers was 0.847 (SE=0.145, p=0.002). Semiquantitative analysis showed a higher mediastinum uptake of the (99m)Tc-UBI 29-41 in patients with mediastinitis than that derived from patients without mediastinitis. Mean uptake of (99m)Tc-UBI 29-41 was 60.4+/-10.3 counts/pixel and 47.4+/-5.5 counts/pixel, respectively (p=0.01). At the threshold value of > or =57 counts/pixel using ROC analysis, the sensitivity, specificity, positive predictive value, negative predictive value and overall diagnostic accuracy for detecting patients with mediastinitis were 83, 100, 100, 87, and 92%, respectively (p=0.02; 95% CI: 0.65-1.10%). (99m)Tc-UBI 29-41 imaging yielded fast and promising first results for patients with suspected mediastinitis after cardiac surgery and, as such, deserves further investigation. | 18,996,290 |
Identification of placental leucine aminopeptidase and triton-slowed aminopeptidase N in serum of pregnant women. | Previously, we found characteristic triton-slowed bands of aminopeptidase N (APN) in cholestatic serum by triton-polyacrylamide gel electrophoresis (triton-PAGE) [Makoto Kawai, Yukichi Hara, Triton-polyacrylamide gel electrophoresis and leucine aminopeptidase activity staining detect Triton-slowed bands including high-molecular-mass aminopeptidase N (CD13) isoform in cholestatic patient sera. Clin Chim Acta 2006; 364:188-195]. Sera from 14 normal pregnant women were electrophoresed on polyacrylamide gel containing 0.02 l/l triton (triton-PAGE) or a 0-0.02 l/l horizontal gradient of triton (gradient-triton-PAGE), and stained with leucine-beta-naphthylamide. Some samples were pretreated with a monoclonal APN antibody or rabbit anti-placental leucine aminopeptidase (PLAP) serum. The stained bands were eluted from the gel, treated with N- and O-glycosidase, and analyzed by Western blotting with rabbit anti-APN or anti-PLAP serum. Triton-PAGE clearly differentiated 5 LAP activity bands (1-5 from the front). Gradient-triton-PAGE revealed that bands 4-5 were slowed by triton (triton-slowed bands) much more than bands 1-3. Triton-PAGE of antibody-treated serum showed that bands 1, 2, 4, and 5 are mainly APN and that band 3 is PLAP. The molecular mass of PLAP was about 130-140 kDa before treatment with glycosidases but 100 kDa after. Triton-PAGE detected PLAP in 13 and triton-slowed APN in 4 of the 14 women. Triton-PAGE differentiates PLAP from APN. Triton-slowed APN as well as PLAP is present in the serum of pregnant women. | 18,996,364 |
A strategy for screening an inhibitor of viral silencing suppressors, which attenuates symptom development of plant viruses. | To find out whether we can control plant virus diseases by blocking viral RNA silencing suppressors (RSSs), we developed a strategy to screen inhibitors that block the association of RSSs with siRNAs using a surface plasmon resonance assay. The screened chemicals were tested in competition with RSSs for binding to siRNAs using a mobility shift assay. We then confirmed that tested chemicals actually inhibited the RSS activity in vivo using a protoplast assay which was developed for this purpose. This entire system can be adapted to screening inhibitors of not only plant viruses but also some animal viruses possessing RSSs. | 18,996,375 |
Rapid characterization of binding specificity and cross-reactivity of antibodies using recombinant human protein arrays. | Antibodies are routinely used as research tools, in diagnostic assays and increasingly as therapeutics. Ideally, these applications require antibodies with high sensitivity and specificity; however, many commercially available antibodies are limited in their use as they cross-react with non-related proteins. Here we describe a novel method to characterize antibody specificity. Six commercially available monoclonal and polyclonal antibodies were screened on high-density protein arrays comprising of ~10,000 recombinant human proteins (Imagenes). Two of the six antibodies examined; anti-pICln and anti-GAPDH, bound exclusively to their target antigen and showed no cross-reactivity with non-related proteins. However, four of the antibodies, anti-HSP90, anti-HSA, anti-bFGF and anti-Ro52, showed strong cross-reactivity with other proteins on the array. Antibody-antigen interactions were readily confirmed using Western immunoblotting. In addition, the redundant nature of the protein array used, enabled us to define the epitopic region within HSP90 of the anti-HSP90 antibody, and identify possible shared epitopes in cross-reacting proteins. In conclusion, high-density protein array technology is a fast and effective means for determining the specificity of antibodies and can be used to further improve the accuracy of antibody applications. | 18,996,391 |
Can morphing methods predict intermediate structures? | Movement is crucial to the biological function of many proteins, yet crystallographic structures of proteins can give us only a static snapshot. The protein dynamics that are important to biological function often happen on a timescale that is unattainable through detailed simulation methods such as molecular dynamics as they often involve crossing high-energy barriers. To address this coarse-grained motion, several methods have been implemented as web servers in which a set of coordinates is usually linearly interpolated from an initial crystallographic structure to a final crystallographic structure. We present a new morphing method that does not extrapolate linearly and can therefore go around high-energy barriers and which can produce different trajectories between the same two starting points. In this work, we evaluate our method and other established coarse-grained methods according to an objective measure: how close a coarse-grained dynamics method comes to a crystallographically determined intermediate structure when calculating a trajectory between the initial and final crystal protein structure. We test this with a set of five proteins with at least three crystallographically determined on-pathway high-resolution intermediate structures from the Protein Data Bank. For simple hinging motions involving a small conformational change, segmentation of the protein into two rigid sections outperforms other more computationally involved methods. However, large-scale conformational change is best addressed using a nonlinear approach and we suggest that there is merit in further developing such methods. | 18,996,395 |
Redesigned immunization card and center-based education to reduce childhood immunization dropouts in urban Pakistan: a randomized controlled trial. | In Pakistan during 2000-2004, about 11-13% of children who received the first dose of diphtheria-pertussis-tetanus (DPT1) failed to complete its third dose (DPT3). We assessed the effect of a redesigned immunization card and center-based education to mothers on DPT3 completion. We enrolled 1500 mother-child units at DPT1, randomized them to three intervention and one standard care groups, and recorded their DPT3 visits during a 90-day follow-up. In multivariable analysis, a significant increase of 31% (adjusted RR=1.31, 95% CI=1.18-1.46) in DPT3 completion was estimated in the group that received both redesigned card and center-based education compared with the standard care group. | 18,996,423 |
The distribution of gamma-hydroxybutyrate-induced Fos expression in rat brain: comparison with baclofen. | gamma-Hydroxybutyrate (GHB) is a euphoric, prosocial and sleep inducing drug that binds with high affinity to its own GHB receptor site and also more weakly to GABA(B) receptors. GHB is efficacious in the treatment of narcolepsy and alcoholism, but heavy use can lead to dependence and withdrawal. Many effects of GHB (sedation, hypothermia, catalepsy) are mimicked by GABA(B) receptor agonists (e.g. baclofen). However other effects (euphoric and prosocial effects and a therapeutic effect in narcolepsy) are not. The present study used Fos immunohistochemistry to assess the neural activation produced in rat brain by medium to high doses of GHB (250, 500 and 1000 mg/kg) and a high dose of baclofen (10 mg/kg) that produced similar sedation to 500 mg/kg GHB. Results showed many common regions of activation with these two drugs including the supraoptic, paraventricular, median preoptic and ventral premammillary nuclei of the hypothalamus, the central nucleus of the amygdala, Edinger-Westphal nucleus, lateral parabrachial nucleus, locus coeruleus, and nucleus of the solitary tract. GHB (500 mg/kg), but not baclofen (10 mg/kg), induced significant Fos expression in the median raphe nucleus and lateral habenula, while a higher dose of GHB (1000 mg/kg) induced additional Fos expression in the islands of Calleja, dentate gyrus (polymorphic layer) and arcuate nucleus, and in various regions implicated in rapid and non-rapid eye movement sleep (laterodorsal tegmental nucleus, tuberomammillary nucleus and the ventrolateral and anterodorsal preoptic nuclei). Surprisingly, Fos immunoreactivity was not observed with either GHB or baclofen in reward-relevant regions such as the nucleus accumbens, striatum and ventral tegmental area. Overall these results indicate a distinctive signature of brain activation with GHB that may be only partly due to GABA(B) receptor effects. This confirms a unique neuropharmacological profile for GHB and indicates key neural substrates that may underlie its characteristic influence on sleep, body temperature, sociability and endocrine function. | 18,996,447 |
Hamster exhibits major differences in organ-specific metabolism of the esophageal carcinogen N-nitrosodiethylamine. | Nitrosamines are carcinogens that require metabolic activation by CYP enzymes in order to exert their carcinogenic effect. Species differences exist in their esophageal carcinogenic potency, with the rat being the most sensitive and the Syrian hamster a resistant species. In the latter, the liver is the main target organ. This difference does not apply to directly acting N-nitroso compounds, suggesting that tissue-specific metabolic activation is involved in hamster esophageal resistance to nitrosamines. We have previously shown that Cytochrome P450 2A3 (CYP2A3) is responsible for N-nitrosodiethylamine activation in the rat esophagus. In order to find a mechanistic explanation for the resistance of hamster esophagus for nitrosamines, we have compared the metabolism of NDEA between esophagus and liver of the hamster. Hamster esophagus is capable of activating NDEA (K(m)=1.02+/-0.44microM and V(max)=1.96+/-0.26nmol acetaldehyde/min/mg microsomal protein). However, the hamster liver showed a 40-fold higher catalytic efficiency (V(max)/K(m)) towards NDEA metabolism compared with its esophagus. Hamster esophagus expresses CYP2A8, CYP2A9 and CYP2A16, but not CYP2E1. An antibody against human CYP2A6 was able to inhibit NDEA metabolism in hamster esophageal, but not liver microsomes. Our results suggest that in the hamster esophagus, but not in the liver, most of the NDEA is metabolized by CYP2A enzymes, but with a rather poor efficiency when compared to the liver. This is in accordance with previous results showing that for the hamster, the main target organ of NDEA is the liver. | 18,996,452 |
Poly(ethylene glycol)-mesalazine conjugate for colon specific delivery. | Chronic inflammatory bowel diseases (IBDs) are still waiting for improved and innovative therapeutic treatments, which can overcome the limits of the current approaches. Since IBDs affect mainly the lower tract of the intestine, a localized therapy in the colon tract will avoid most of the problems caused by systemic or poor selective therapies. Particularly promising are the advance drug delivery systems that can reach specific colon delivery, thus guaranteeing active agent release only at the site of action. This approach can meet two aims at the same time, first of all the drug will not affect healthy tissue and second a lower drug dose may be used because all the administered active agent will reach the target. To obtain a specific colon delivery we exploited the azoreductase enzymes, selectively present only in colon, by inserting an azo linker between a selected drug and a macromolecular carrier. The drug employed is mesalazine, a well know and used agent against IBDs. Poly(ethylene glycol) (PEG), of different molecular weights and structures, was used as carrier. Three different conjugates were synthesized and characterized, and the most promising one, with highest drug loading thanks to the use of diamino PEG of 4 kDa, was further investigated in vitro on mouse colonic epithelial cells (CMT-9) and in vivo on model mice with induced colitis. The data presented here demonstrate that PEG conjugation of mesalazine prevents drug release and absorption in upper intestine, after oral administration of the conjugates, and that the azo linker ensures a good drug release in the colon tract. The results in vivo take into consideration mice bodyweight gain, tissue histology and interleukin-2 beta as an index of inflammation. These parameters, all together, demonstrated the conjugate effectiveness against the controls. | 18,996,458 |
Activation of transcription factors and gene expression by oxidized low-density lipoprotein. | It is well recognized that oxidized LDL (OxLDL) plays a crucial role in the initiation and progression of atherosclerosis. Many biological effects of OxLDL are mediated through signaling pathways, especially via the activation of transcription factors, which in turn stimulate the expression of genes involved in the inflammatory and oxidative stress response or in cell cycle regulation. In this review, we will discuss the various transcription factors activated by OxLDL, the studied cell types, the active compounds of the OxLDL particle, and the downstream genes when identified. Identification of the transcription factors and some of the downstream genes regulated by OxLDL has helped us understand the molecular mechanism involved in generation of the atherosclerotic plaque. | 18,996,472 |
Early treatment with Lactobacillus delbrueckii strain induces an increase in intestinal T-cells and granulocytes and modulates immune-related genes of larval Dicentrarchus labrax (L.). | Lactobacillus delbrueckii ssp. delbrueckii (AS13B), isolated from the gut of adult Dicentrarchus labrax, was administered live to developing sea bass using rotifers and Artemia as live carriers. Immune-related gene transcripts were quantified in post-larvae at day 70 post-hatch (ph) and histology, electron microscopy and immunocytochemistry of the intestinal tissue were performed at day 74 ph. Since the probiotic was orally administered the studies were focused on intestinal immunity. In treated fish gut integrity was unaffected, while the density of T-cells and acidophilic granulocytes in the intestinal mucosa was significantly higher than in controls. Probiotic-induced increases in intestinal T-cells and total body TcR-beta transcripts are first reported in fish. Significantly lower IL-1beta transcripts and a trend towards lower IL-10, Cox-2 and TGF-beta transcription were found in the treated group. Evidence is provided that early feeding with probiotic-supplemented diet stimulated the larval gut immune system and lowered transcription of key pro-inflammatory genes. | 18,996,487 |
Functional brain correlates of social and nonsocial processes in autism spectrum disorders: an activation likelihood estimation meta-analysis. | Functional neuroimaging studies of autism spectrum disorders (ASD) have examined social and nonsocial paradigms, although rarely in the same study. Here, we provide an objective, unbiased survey of functional brain abnormalities in ASD, related to both social and nonsocial processing. We conducted two separate voxel-wise activation likelihood estimation meta-analyses of 39 functional neuroimaging studies consisting of 24 studies examining social processes (e.g., theory of mind, face perception) and 15 studies examining nonsocial processes (e.g., attention control, working memory). Voxel-wise significance threshold was p<.05, corrected by false discovery rate. Compared with neurotypical control (NC) subjects, ASD showed greater likelihood of hypoactivation in two medial wall regions: perigenual anterior cingulate cortex (ACC) in social tasks only and dorsal ACC in nonsocial studies. Further, right anterior insula, recently linked to social cognition, was more likely to be hypoactivated in ASD in the analyses of social studies. In nonsocial studies, group comparisons showed greater likelihood of activation for the ASD group in the rostral ACC region that is typically suppressed during attentionally demanding tasks. Despite substantial heterogeneity of tasks, the rapidly increasing functional imaging literature showed ASD-related patterns of hypofunction and aberrant activation that depended on the specific cognitive domain, i.e., social versus nonsocial. These results provide a basis for targeted extensions of these findings with younger subjects and a range of paradigms, including analyses of default mode network regulation in ASD. | 18,996,505 |
Asymmetric epoxidation of unfunctionalized alkenes catalyzed by sugar moiety-modified chiral salen-Mn(III) complexes. | Several chiral Schiff-base ligands with sugar moieties at C-3 (3') or C-5 (5') of salicylaldehyde were synthesized from reaction of salicylaldehyde derivatives with diamine. These ligands coordinated with Mn(III) to afford the corresponding chiral salen-Mn(III) complexes characterized by FT-IR, MS, and elementary analysis. These complexes were used as catalysts for the asymmetric epoxidation of unfunctionalized alkenes. Only weak enantioselectivity is induced by the chiral sugar moieties at C-3 (3') or C-5 (5') in the case of absence of chirality in the diimine bridge moiety. It was also shown that the sugars at C-5 (5') having the same rotation direction of polarized light as the diimine bridge in the catalyst could enhance the chiral induction in the asymmetric epoxidation, but the sugars with the opposite rotation direction would reduce the chiral induction. | 18,996,511 |
Relationship of handgrip strength with anthropometric and body composition variables in prepubertal children. | The purpose of the present study was to examine the relationship of handgrip strength with basic anthropometric variables, hand anthropometric variables, total body and hand composition, total body and hand bone mineral density (BMD) and bone mineral content (BMC) in prepubertal children aged between 8 and 11 years (n=64, 27 boys, 37 girls). Height and body mass were measured and body mass index (BMI kg/m2) was calculated. Biceps and triceps skinfolds, arm relaxed, arm flexed, forearm and wrist girths, acromiale-radiale, radiale-stylion-radiale and midstylion-dactylion length and humerus breadth were measured. Specific hand anthropometric variables according to Visnapuu and Jürimäe [2007. Handgrip strength and hand dimensions in young handball and basketball players. J. Strength Cond. Res. 21, 923-929] were used. Five fingers' spans, fingers' lengths and perimeters of the hand were measured. Total body and right-hand fat percentage, fat mass and lean mass (LBM) were measured by dual-energy X-ray absorptiometry (DXA). Right-hand BMC and BMD were analysed from the bone variables. Maximal handgrip strength of the right hand was measured with the hand dynamometer. Stepwise multiple regression analysis indicated that the most important predictive value from the basic anthropometric variables was body height, explaining 76.1% (R2 x 100), 40.7% and 50.6% of the handgrip strength in boys, girls and total group, respectively. Measured skinfold thicknesses and breadths were not related to handgrip strength in any group. Forearm girths significantly predicted handgrip strength in boys (30.8%), girls (43.4%) and total group (43.4%). As a rule, handgrip strength was more dependent on the anthropometric and body composition variables in boys than girls. It was concluded that body height, forearm girth, midstylion-dactylion and acromiale-radiale length and hand LBM and BMC are the most limiting factors influencing handgrip strength in prepubertal children. | 18,996,520 |
Efficacy and safety of ABT-335 (fenofibric acid) in combination with rosuvastatin in patients with mixed dyslipidemia: a phase 3 study. | To evaluate a new formulation of fenofibric acid (ABT-335) co-administered with 2 doses of rosuvastatin in patients with mixed dyslipidemia. In a phase 3, multicenter, randomized, double-blind, active-controlled study, a total of 1445 patients with LDL-C>or=130 mg/dL, TG>or=150 mg/dL, and HDL-C<40 mg/dL (<50 mg/dL for women) were randomized to either ABT-335 (135 mg), rosuvastatin (10, 20, or 40 mg), or ABT-335+rosuvastatin 10 or 20 mg, and treated for 12 weeks. The primary efficacy comparisons were mean percent change in HDL-C and TG (ABT-335+rosuvastatin vs. corresponding dose of rosuvastatin), and LDL-C (ABT-335+rosuvastatin vs. ABT-335). Combination therapy with ABT-335+rosuvastatin 10 mg resulted in significantly (p<0.001) greater improvements in HDL-C (20.3% vs. 8.5%) and TG (-47.1% vs. -24.4%) compared to rosuvastatin 10 mg; and LDL-C (-37.2% vs. -6.5%) compared to ABT-335. Similarly, significantly (p<0.001) greater improvements were observed with ABT-335+rosuvastatin 20 mg in HDL-C (19.0% vs. 10.3%) and TG (-42.9% vs. -25.6%) compared to rosuvastatin 20 mg; and LDL-C (-38.8% vs. -6.5%) compared to ABT-335 monotherapy. Greater improvements in multiple secondary endpoints were noted with combination therapy compared to prespecified monotherapies. Both combination therapy doses were generally well tolerated, with a safety profile consistent with ABT-335 and rosuvastatin monotherapies. No rhabdomyolysis or unexpected hepatic, renal, or muscle safety signals were identified. In patients with mixed dyslipidemia, combination therapy with ABT-335+rosuvastatin resulted in more effective control of multiple lipid parameters than either monotherapy alone, with a safety profile similar to both monotherapies. This combination may be an appropriate therapeutic option to treat mixed dyslipidemia. | 18,996,523 |
Adipose tissue as a source of nicotinamide N-methyltransferase and homocysteine. | Nicotinamide N-methyltransferase (NNMT) catalyses the conversion of nicotinamide to 1-methylnicotinamide and plays an important role in hepatic detoxification reactions. Here we show that, in addition to the liver, 3T3-L1 adipocytes as well as human and murine adipose tissue explants express high amounts of enzymatically active NNMT. NNMT mRNA levels and enzyme activity increased in 3T3-L1 cells in a differentiation-dependent manner. Homocysteine, the atherogenic product of the NNMT-catalyzed reaction, was secreted from 3T3-L1 cells or adipose tissue cultures. Homocysteine release increased during 3T3-L1 differentiation and was reduced when adipose tissue was treated with the NNMT inhibitor 1-methylnicotinamide. Nicotinic acid (NA), a widely used drug to lower elevated plasma lipid levels, induced NNMT enzyme activity in white adipose tissue of mice. In tissue culture nicotinamide treatment led to an increase in adipose tissue homocysteine secretion. These data support the concept that adipose tissue NNMT contributes to the increased plasma homocysteine levels in patients treated with NA. | 18,996,527 |
A wearable system for pre-impact fall detection. | Unique features of body segment kinematics in falls and activities of daily living (ADL) are applied to make automatic detection of a fall in its descending phase, prior to impact, possible. Fall-related injuries can thus be prevented or reduced by deploying fall impact reduction systems, such as an inflatable airbag for hip protection, before the impact. In this application, the authors propose the following hypothesis: "Thigh segments normally do not exceed a certain threshold angle to the side and forward directions in ADL, whereas this abnormal behavior occurs during a fall activity". Torso and thigh wearable inertial sensors (3D accelerometer and 2D gyroscope) are used and the whole system is based on a body area network (BAN) for the comfort of the wearer during a long term application. The hypothesis was validated in an experiment with 21 young healthy volunteers performing both normal ADL and fall activities. Results show that falls could be detected with an average lead-time of 700 ms before the impact occurs, with no false alarms (100% specificity), a sensitivity of 95.2%. This is the longest lead-time achieved so far in pre-impact fall detection. | 18,996,529 |
Brain activities associated with gaming urge of online gaming addiction. | The aim of this study was to identify the neural substrates of online gaming addiction through evaluation of the brain areas associated with the cue-induced gaming urge. Ten participants with online gaming addiction and 10 control subjects without online gaming addiction were tested. They were presented with gaming pictures and the paired mosaic pictures while undergoing functional magnetic resonance imaging (fMRI) scanning. The contrast in blood-oxygen-level dependent (BOLD) signals when viewing gaming pictures and when viewing mosaic pictures was calculated with the SPM2 software to evaluate the brain activations. Right orbitofrontal cortex, right nucleus accumbens, bilateral anterior cingulate and medial frontal cortex, right dorsolateral prefrontal cortex, and right caudate nucleus were activated in the addicted group in contrast to the control group. The activation of the region-of-interest (ROI) defined by the above brain areas was positively correlated with self-reported gaming urge and recalling of gaming experience provoked by the WOW pictures. The results demonstrate that the neural substrate of cue-induced gaming urge/craving in online gaming addiction is similar to that of the cue-induced craving in substance dependence. The above-mentioned brain regions have been reported to contribute to the craving in substance dependence, and here we show that the same areas were involved in online gaming urge/craving. Thus, the results suggest that the gaming urge/craving in online gaming addiction and craving in substance dependence might share the same neurobiological mechanism. | 18,996,542 |
Electro-Fenton degradation of synthetic dyes. | The electrochemical removal of a synthetic solution containing 120mgL(-1) of alizarin red has been studied by electro-Fenton process using a gas-diffusion cathode to produce in situ hydrogen peroxide by oxygen reduction. The effect of operating conditions such as Fe(2+) concentration, applied current, solution pH and temperature on the efficacy of the process was investigated. It is shown that alizarin red and its products may be effectively degraded by the OH radicals produced by the reaction between the Fe(2+) ions and the electrogenerated H(2)O(2). After 4h of electrolysis COD removal was only 45% when no ferrous ions were added to the solutions, while the presence of ferrous ion greatly improved COD removal up to more than 90%. In particular 1.0mM was the optimal concentration of ferrous ions and the single step or the stepwise addition of Fe(2+) ions enables the same COD removal. The oxidation rate increased with increasing of current density and temperature and with decreasing of pH. The UV-vis analysis indicated that the discoloration of the solution occurs simultaneous with the destruction of aromatic rings and alizarin red is oxidised firstly to colourless intermediates (mainly phthalic acid, small carbonyl species) and then to carbon dioxide. | 18,996,554 |
Controlled remineralization of enamel in the presence of amelogenin and fluoride. | Reconstructing enamel-like structures on teeth have been an important topic of study in the material sciences and dentistry. The important role of amelogenin in modulating the mineralization of organized calcium phosphate crystals has been previously reported. We used amelogenin and utilized a modified biomimetic deposition method to remineralize the surface of etched enamel to form mineral layers containing organized needle-like fluoridated hydroxyapatite crystals. The effect of a recombinant amelogenins (rP172) on the microstructure of the mineral in the coating was analyzed by SEM, XRD and FT-IR. At rP172 concentrations below 33 microg/mL, no significant effect was observed. In the presence of 1 mg/L F and at a concentration of 33 microg/mL rP172, formation of fused crystals growing from the enamel surface was initiated. Amelogenin promoted the oriented bundle formation of needle-like fluoridated hydroxyapatite in a dose dependent manner. Biomimetic synthesis of the amelogenin fluoridated hydroxyapatite nano-composite is one of the primary steps towards the development and design of novel biomaterial for future application in reparative and restorative dentistry. | 18,996,587 |
Medication treatment perceptions, concerns and expectations among depressed individuals with Type I Bipolar Disorder. | Subjective experience of illness affects outcomes among populations with bipolar disorder (BD). This cross-sectional study combined qualitative and quantitative approaches to evaluate perceived treatment effects, concerns and expectations among 90 individuals with BD. Adults with Type I BD, mean age 36.6 years, 51% women, completed a semi-structured interview that was audio taped, transcribed, coded and analyzed along emergent themes. Quantitative scales measured depressive symptoms (Hamilton Depression Scale/HAM-D), psychopathology (Clinical Global Impression/CGI), and insight and treatment attitudes (Insight and Treatment Attitudes Questionnaire/ITAQ). Individuals had moderate depression and psychopathology with good insight into need for treatment. Drug treatment was perceived as beneficial, by "stabilizing" or "balancing" mood (42%, N=38), decreasing anxiety/depressive symptoms (19%, N=17) and improving sleep (10%, N=9). While 39%, (N=35) of individuals denied medication concerns, nearly 29%, (N=26) feared possible long-term effects, particularly diabetes or liver/kidney damage. Media stories and advertisements contributed to medication fears. Hopes and expectations for treatment ranged from those that were symptom or functional status-based, such as desiring mood stabilization and elimination of specific symptoms (23%, N=21), to more global hopes such as "being normal" (20%, N=18) or "cured" (18%, N=16). Limitations include relatively small sample, lack of a comparator, inclusion of only depressed individuals and those willing to discuss their illness experience. While individuals with BD appreciate the effects of medications, concerns regarding adverse effects and discrepancy between actual and hoped-for outcomes can be substantial. Subjective experience with medications using qualitative and quantitative methods should be explored in order to optimize treatment collaboration and outcomes. | 18,996,600 |
Radiotherapy to the chest wall following mastectomy for node-negative breast cancer: a systematic review. | Although nodal status is the major determinant of risk of locoregional relapse (LRR), other factors also contribute, and these assume a greater significance for those with node-negative breast cancer. Previous reviews of post-mastectomy radiotherapy have included studies using radiotherapy techniques or doses no longer considered clinically appropriate. To determine the effectiveness of post-mastectomy radiotherapy in women with node-negative breast cancer with particular reference to those patient and tumour factors which contribute to an increased risk of LRR. A systematic literature review was conducted. Trials using inadequate or orthovoltage radiotherapy were excluded. Data linking potential risk factors, either individually or in combination, to the occurrence of LRR were handled qualitatively. Data from randomised trials of post-mastectomy radiotherapy were included in a meta-analysis. Baseline risk of LRR is increased in the presence of lymphovascular invasion, a grade 3 tumour, tumours greater than 2 cm or a close resection margin and in patients who are pre-menopausal or aged less than 50. Those with no risk factors have a baseline risk of LRR of approximately 5% or less rising to a risk of 15% or more for those with two or more risk factors. In the meta-analysis of three randomised trials of mastectomy and axillary clearance (667 patients), the addition of radiotherapy resulted in an 83% reduction in the risk of LRR (P < 0.00001) and in a 14% improvement in survival (P = 0.16). The use of post-mastectomy radiotherapy for women with node-negative breast cancer requires re-evaluation. Radiotherapy should be considered for those with two or more risk factors. | 18,996,609 |
Necessary organizational changes according to Burke-Litwin model in the head nurses system of management in healthcare and social welfare institutions - the Slovenia experience. | To discover which changes should be implemented in the system of head nursing management in Slovenian healthcare institutions and social welfare institutions. The questionnaire was distributed to 155 head nurses of Slovenian hospitals, primary healthcare centres and social welfare institutions. The Burke-Litwin organizational change model has been used to look at which changes have to be implemented in the management system of head nurses. In hospitals head nurses have greater independent competence for planning professional training of nursing employees (p<.022) and are also more independent when it comes to selecting employees when it comes to new job openings (M=4.20, S.D.=.83, p<.004). According to the Burke-Litwin organizational change model, the elements to which changes should be introduced include "external environment" for primary healthcare centres and social welfare institutions, and "system (policies and procedures)" for primary healthcare centres. According to results of our study, changes are needed in leadership and management of nursing in primary healthcare centres. In social welfare institutions changes are only required in leadership. Organizational changes are not necessary for any element of the Burke-Litwin model for hospitals. | 18,996,612 |
Photolytic degradation of polybromodiphenyl ethers under UV-lamp and solar irradiations. | Polybromodiphenyl ethers (PBDEs) are widely used flame retardant additives and have been mainly used in polymers for many plastic and electronic products. PBDEs have been found to bioaccumulate in both aquatic and terrestrial ecosystems and even human bodies. The technical product with the highest use is decabrominated diphenyl ether (BDE-209). Therefore, we chose to examine the solar and UV-lamp degradation of BDE-209. A linear increase of the photodegradation rate constant for BDE-209 was observed with the solar light intensity. The degradation reactions follow the pseudo-first-order kinetics. The photodegradation of BDE-209 produced other less brominated diphenyl ethers under ultraviolet light exposure, suggesting that the photodegradation of BDE-209 is a sequential dehalogenation mechanism. BDE-209 underwent rapid reductive debromination in these photodecomposition experiments. The formation rate constants of three nonabromodiphenyl ethers increase with the order of BDE-206, BDE-207 and BDE-208, indicating debromination mainly occurred at para>meta>ortho positions. These findings of the process properties and reductive debromination mechanism of the photolytic degradation of PBDEs can facilitate the design of remediation processes and also aid in predicting their fate in the environment. | 18,996,643 |
Towards the clinical application of X-ray phase contrast imaging. | Synchrotron-based propagation-based imaging, a type of phase contrast imaging, produces better soft tissue image contrast than conventional radiography. To determine whether the technique is directly transferable to the clinical environment for routine diagnostic or screening imaging, a micro-focus (100 microm spot-size) Molybdenum X-ray source with 0.03 mm molybdenum filtration was installed at a local hospital. Breast tissue samples, excised masses and mastectomies, were obtained directly from surgery and imaged at three geometries. The first geometry was optimised for visualizing phase contrast effects using a ray-line argument, the second was the same as that employed by Konica-Minolta in their commercial phase contrast system, and the third was the conventional contact arrangement. The three images taken of each tissue sample were comparatively scored in a pair-wise fashion. Scoring was performed by radiologist expert in mammography, general radiologists, associated clinicians and radiographers on high-resolution mammography rated monitors at two separate locations. Scoring indicated that the optimised and Konica geometries both outperformed the conventional mammographic geometry. An unexpected complication within the trial was the effect that the scoring platform and the associated display tools had on some of the scorer's responses. Additionally, the trial revealed that none of the conventional descriptors for image quality were adequate in the presence of phase contrast enhancements. | 18,996,661 |
Endovascular repair or medical treatment of acute type B aortic dissection? A comparison. | The aim of this retrospective study was to compare the outcome of thoracic endovascular aortic repair (TEVAR) to that of medical therapy in patients with acute type B aortic dissection (TBD). From July 1996 to April 2008, 88 patients presenting with acute TBD underwent either TEVAR (group A, n=38) or medical therapy (group B, n=50). Indications for TEVAR were intractable pain, aortic branch compromise resulting in end-organ ischemia, rapid aortic dilatation and rupture. Follow-up was performed postinterventionally, at 3, 6 and 12 months and yearly thereafter and included clinical examinations and computed tomography (CT), as well as aortic diameter measurements and assessment of thrombosis. Mean follow-up was 33 months in group A and 36 months in group B. The overall mortality rate was 23.7% in group A and 24% in group B, where 4 patients died of late aortic rupture. In group A, complications included 9 endoleaks and 4 retrograde type A dissections, 3 patients were converted to open surgery and 2 needed secondary intervention. None of the patients developed paraplegia. In group B, 4 patients were converted to open surgery and 2 to TEVAR. The maximal aortic diameter increased in both groups. Regarding the extent of thrombosis, our analyses showed slightly better overall results after TEVAR, but they also showed a tendency towards approximation between the two groups during follow-up. TEVAR is a feasible treatment option in acute TBD. However, several serious complications may occur during and after TEVAR and it should therefore be reserved to patients with life-threatening symptoms. | 18,996,662 |
The development of methodology for clinical measurement of 5-lipoxygenase pathway intermediates from human peripheral blood mononuclear cells. | Recent studies have shown a correlation between 5-lipoxygenase (5-LO) pathway up-regulation and cardiovascular risk. Despite the existence of several assays for products of the 5-LO pathway, a reliable method for clinical determination of 5-LO activity remains to be established. In the present communication, we report conditions that allow measurement of 5-hydroxyeicosatetraenoic acid (5-HETE) and leukotriene B(4) (LTB(4)) in peripheral blood mononuclear cells (PBMCs) isolated from the blood of atherosclerosis patients before and after stimulation by the calcium ionophore, A23187. LTB(4), a potent mediator of inflammation-linked cardiovascular disease, was measured using an existing competitive enzyme immunoassay (EIA) kit after making specific methodological improvements that allowed PBMCs to be used in this format for the first time. LTB(4) was also measured by LC/MS/MS along with 5-HETE, a direct by-product of the action of 5-LO on arachidonic acid and a molecule for which no commercial EIA kit exists. The LC/MS/MS assay was validated over a range of 0.025-25ng/mL for LTB(4) and 0.1-25ng/mL for 5-HETE. The EIA method has a validated range covering 0.025-4ng/mL. When both assays were applied to analyze LTB(4) from stimulated PBMCs isolated from 25 subjects with various degrees of atherosclerosis, a high correlation was obtained (r=0.9426, Pearson's correlation coefficient). A high correlation was also observed between the levels of LTB(4) and 5-HETE measured by LC/MS/MS after ionophore stimulation (r=0.9159). Details are presented for optimized sample collection, processing, storage, and analysis in accordance with the logistical demands of clinical analysis. | 18,996,667 |
Prevalence of hepatitis C, hepatitis B, and human immunodeficiency virus in a Grand Rapids, Michigan emergency department. | The objective of this study is to provide updated prevalence information on hepatitis C, hepatitis B, and human immunodeficiency virus (HIV) among patients in a high-volume emergency department (ED) located in a medium-sized, Midwestern city. This study provides updated information regarding the prevalence of the blood-borne pathogens hepatitis C, hepatitis B, and HIV among ED patients. Prior studies of this type have focused on large inner-city populations with high incidence rates of blood-borne diseases. These studies have limited applicability to other common ED settings. A convenience sample of 404 patients was selected using blood previously drawn independent of the study. Patient-identifying information was unlinked from study results, which allowed waiver of informed consent from the Institutional Review Board. This blood was then tested for hepatitis C, hepatitis B, and HIV. Prevalence of hepatitis C antibody was 4.0%, relative to the overall US population prevalence of 1.8%. Hepatitis B(s)Ag was present in 0.7% and HIV prevalence was 0.8%. There were no coinfections; therefore, there was a combined prevalence of blood-borne pathogens of 5.5%. The combined prevalence of blood-borne pathogens of 5.5% supports previous recommendations of universal precautions, particularly in settings where the overall prevalence may be underestimated. | 18,996,668 |
Isolated, spontaneous superior mesenteric and celiac artery dissection: case report and review of literature. | Spontaneous, isolated dissection of the superior mesenteric artery (SMA) and celiac artery (CA) is rare. Although there are known risk factors, there is no particular mechanism that is common to vascular dissections. The objectives of this study were to review the current literature on diagnosis and treatment of isolated SMA and CA dissection, and to review aortic complications in giant cell arteritis, Takayasu arteritis, and polyarteritis nodosa. Giant cell arteritis, Takayasu arteritis, and polyarterteritis nodosa are vasculitides that are associated with SMA and CA dissection. An interesting aspect of this case is that the patient was a healthy person before presentation, and ultimately, did not have an underlying etiology to explain the dissection. In addition, the patient was successfully managed without operative intervention. Although there are known risk factors in patients who present with isolated, spontaneous SMA and CA dissection, the pathogenesis is still unclear. The prognosis has improved significantly with the early use of computed tomography angiography to diagnosis this entity. Although most cases require surgical intervention, there are some, as in this case, that are managed non-operatively. | 18,996,673 |
Comparison of the interfacial properties of Eugenia uniflora and Triticum vulgaris lectins. | We have investigated the interfacial and dielectric properties of EuniSL, a recently purified lectin obtained from seeds of Eugenia uniflora (EuniSL), through surface pressure (Pi) and surface potential (DeltaV) measurements of its floating monolayers at the 2.0<pH<9.0 range, and compared the corresponding results to those obtained for Langmuir films of Triticum vulgaris (WGA). The variation of Pi and DeltaV as a function of the molecular area reveals that while the interfacial properties of both lectins are strongly dependent upon the pH of bulk phase, in general terms EuniSL monolayers seem to be more structured than those of WGA. At the pH range investigated, the interfacial electric double layer values (Psi(0)) calculated from the surface potential are negative, both for EuniSL and WGA. While for EuniSL definite breakpoints in an otherwise linear dependence of Psi(0) and zeta-potential as a function of pH were detected at pH 6.5, similar changes were observed for WGA at pH 8.5, a value close to the isoelectric point (pI) of this lectin. We have then used electrical impedance spectroscopy to investigate the dielectric characteristics of aqueous solutions of the two lectins, assuming a simple Debye relaxation model, and determined the pI of EuniSL as 6.5. While it is well known that the pI of a protein dispersed as a Langmuir film can be determined by surface potential measurements, our results confirm the use of impedance spectroscopy as a valuable and convenient technique that allows the identification of the pI of proteins directly dispersed in aqueous solutions. | 18,996,683 |
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