title stringlengths 0 1.13k | abstract stringlengths 1 15.7k | PMID int64 22 36.5M |
|---|---|---|
Clinical and sub-clinical vitamin A deficiency among rural pre-school children of Maharashtra, India. | Although a national vitamin A prophylaxis programme has been in operation for more than three decades, vitamin A deficiency (VAD) continues to be a major nutritional problem of public health significance in India. The present study was carried out with the aim of assessing the prevalence of clinical and sub-clinical VAD among rural pre-school children. A community-based cross-sectional study was carried out in rural areas of Maharashtra State during 2002-2003. A total of 8646 pre-school children were examined for the presence of signs and symptoms of VAD. A sub-sample (494) of them was used to estimate blood vitamin A levels. The prevalence of Bitot's spots (1.3%) and night blindness (1.1%) was higher than the WHO cut-off levels used to define a public health problem, and it increased significantly (p<0.001) with increase in age. The prevalence of Bitot's spots was 13 times higher among children belonging to the Scheduled Caste (OR=12.8), and 20 times higher among the children of labourers (OR=19.8). The prevalence of sub-clinical VAD (55%) was significantly (p<0.001) high among the children with night blindness (100%) and Bitot's spots (89%). Increased vitamin A supplementation, health and nutrition education and consumption of vitamin A rich foods are essential to prevent VAD. | 18,958,633 |
Trichloroethylene Does Not Accelerate Autoimmune Diabetes in NOD Mice. | Pre-existing or contributing risk factors, including genetic predisposition and environmental influences, are largely thought to play a crucial (though ill-elucidated) role in the development of autoimmunity. Trichloroethylene (TCE) is a widely used organic solvent, which has been suspected of increasing the prevalence of autoimmune diseases, e.g., lupus, following environmental contamination. Although few epidemiological data are available, several studies reported an accelerated and more severe disease in TCE-exposed autoimmunity-prone MRL(+/+) mice. To test whether TCE can exert similar deleterious effects on organ-specific autoimmune diseases, non obese diabetic (NOD) mice were given 5 mg/ml TCE via the drinking water for 12 weeks. TCE administration induced a decrease in CD44(+) splenic T-cells and CD45RB(high), CD54(+) blood and splenic T-cells. Conversely, the number of CD45RB(low) splenocytes was increased. Interestingly, the progressive increase in serum TNF-alpha and IFN-gamma levels normally seen with age in these mice was inhibited by TCE. There was also a relative lower incidence of histological changes in the pancreas of TCE-exposed NOD mice than in unexposed mice. Contrary to what has been found in systemic models of autoimmunity, TCE did not accelerate the diabetes of NOD mice and may have a protective effect. This finding suggests that comparative studies using different genetically related autoimmune-prone models are needed to investigate the role of xenobiotics in the precipitation of autoimmunity, particularly in sensitive populations. | 18,958,647 |
2,3,7,8 Tetrachlorodibenzo-p-Dioxin (TCDD) Directly Enhances the Maturation and Apoptosis of Dendritic Cells In Vitro. | 2,3,7,8 Tetrachlorodibenzo-p-dioxin (TCDD) suppresses adaptive immune responses and modulates the function of numerous cells involved in these responses. Our laboratory has shown that dendritic cells (DCs), which are important for the initiation of T-cell-dependent immunity, from TCDD-exposed mice exhibited reduced cell numbers and had altered expression of costimulatory molecules that are critical for the activation of T-cells. To further characterize the effects of TCDD on DCs and to elucidate a potential mechanism of toxicity, we investigated the direct effects of TCDD on DC maturation and survival in vitro. DCs, derived from bone marrow cells, were exposed to TCDD and then treated with TNFalpha to induced maturation. Apoptosis of bone marrow derived DCs (bmDCs) was induced by activating CD95 on the surface of the cells and was measured by annexin V staining. The TCDD-mediated changes in the expression of genes associated with apoptosis were examined using a pathway-specific c-DNA microarray. The results demonstrate that TCDD-treatment of bmDCs enhanced TNFalpha-induced maturation, measured as an increase in the expression of major histocompatibility complex class II, CD86, CD40, and CD54. In addition, TCDD exposure significantly augmented CD95-mediated death of bmDCs and altered the transcription of several genes involved in apoptosis. These findings confirm and extend the in vivo effects of TCDD on DC activation, and suggest that TCDD induces these changes, at least in part, via direct effects on the DC. | 18,958,649 |
Detection of Allergen-Specific IgE Antibody Responses. | Allergen-specific IgE production is the central event in the pathogenesis of atopic disorders and increases in specific IgE serum antibodies are an indicator of immediate hypersensitivity responses in humans and in animal models of allergy. Consequently, accurate and user-friendly methods are needed to measure serum levels of allergen-specific IgE. This review examines historical and recent developments in in vivo and in vitro methods for the detection of allergen-specific IgE in humans and in animal models. Routinely, in vitro methods such as enzyme-linked immunosorbant assays or radioallergosorbant tests and in vivo methods such as the skin prick test (SPT) for humans and the passive cutaneous anaphylaxis assay (PCA) used in animals are utilized to detect allergen-specific IgE. While in vivo assays are usually more accurate than in vitro assays since they provide a functional readout of IgE activity, they are relatively costly and require considerable expertise. On the other hand in vitro assays are limited by the fact that the amount of allergen-specific serum IgG exceeds IgE antibody by several orders of magnitude, resulting in competition for allergen binding. Consequently, methods that use allergen as a direct capture step are limited by the availability of free allergen binding sites for IgE. In order to circumvent this problem, in vitro methods usually require prior depletion of IgG or use high amounts of allergen in order to facilitate availability of free binding sites for IgE detection. Clearly, these approaches are limited for small sample volumes and allergens that are in short supply. New methods such as protein microarray could potentially overcome this problem by providing high allergen concentrations in a relatively small reaction volume. Currently, in vitro methods are rarely used in isolation for prognosis but are used primarily to complement the information obtained from in vivo assays. With the emergence of new technologies it is conceivable that in vitro assays may in the future replace in vivo assays, however until then in vivo assays remain the gold standard of allergen-specific IgE detection. | 18,958,652 |
Effect of methanol intoxication on rat neutrophil functions. | Methanol (MeOH) toxicity, a potential problem from accidental, intentional, as well as occupational and daily ingestion of the agent, receives attention only after severe signs of intoxication have set in or death is imminent. While accidental and intentional exposures involve high doses, the occupational and ingestion forms more often reflect small daily intakes. Still, even at these low levels, little is known about the potential immunotoxic implications from these recurring exposures. As innate immunity confers a first-line of defense against infection, a study was designed to examine the effects of daily exposure to MeOH (at (1)/(4) LD(50) level, for up to 15 or 30 days) on neutrophil (PMN) functions using rats that were (or were not) injected with sheep red blood cells (SRBC) during the course of exposures. Blood samples were analyzed for total (TLC) and differential leucocyte counts (DLC), and isolated neutrophils (PMN) were assessed for changes in function by monitoring phagocytic (PI) and avidity indices (AI), nitroblue tetrazolium (NBT) reduction, and adherence. Body weights were monitored during exposures and weights of major immune system organs (i.e., spleen, thymus, lymph nodes) were assessed at sacrifice. Body and organ weight, TLC, blood PMN levels, PMN PI, and adherence were all significantly decreased in SRBC-untreated rats that received MeOH, although these cells did also display significant increases in AI and NBT reduction. With SRBC-treated rats, though the percentage of PMN in the blood increased with ongoing MeOH exposure, all the other parameters were markedly decreased in comparison to their controls. Thus, this study showed that repeated exposures to MeOH modulates PMN functions, thereby potentially altering the first line of defense in a normal immune response in exposed hosts. | 18,958,665 |
Screening new drugs for immunotoxic potential: III. assessment of the effects of selective and nonselective COX-2 inhibitors on T-cell-dependent antibody and natural killer cell responses in the rat. | Results from earlier experiments in our laboratories revealed that both selective and non-selective inhibitors of cyclooxygenase-2 possess little potential for decreasing in vitro phagocytosis by rat macrophages or canine neutrophils, and no potential for decreasing in vivo phagocytosis by the intact murine immune system. We have also demonstrated that pharmacologically relevant doses and concentrations of these drugs do not reduce canine complement activation, superoxide anion generation, leukocytic chemotaxis or transmigration of leukocytes through endothelial monolayers. We now report the results of immunotoxicology studies to assess the effects of the drugs on cell-mediated immunity. Male and female Sprague-Dawley rats were administered daily oral gavage doses of naproxen (10 mg/kg), SC-791 (2.5 mg/kg), or SC-245 (17 mg/kg) for 28 consecutive days or treated with cyclophosphamide or anti-asialo GM1 antibody as positive immunomodulatory controls (for T-dependent antibody response and natural killer cell assay, respectively). All rats, except those treated with GM1 antibody or used in toxicokinetic analyses, were immunized on study day 25 with sheep red blood cells to induce a primary T-dependent antibody response. The doses of test agents were chosen to be either supra-pharmacologic or limited by anticipated systemic toxicity. Hematologic changes consistent with gastrointestinal (GI) blood loss due to mild GI mucosal toxicity were seen with naproxen and SC-791. Both positive control agents produced anticipated immunomodulatory effects confirming the validity of the assay system. In the antibody-forming cell assay, naproxen, SC-791 and SC-245 were without effects on splenic cellularity, splenocyte viability or the number of sheep red blood cell antibody-forming cells. Cyclophosphamide reduced both splenic cellularity and antibody-forming cell counts. In the natural killer cell assay, naproxen, SC-791 and SC-245 were all without effects on natural killer cell activity, while anti-asialo antibody reduced natural killer cell activity up to 85%. In considering the sum total of scientific information relative to the immunotoxicological potential of non-selective and selective cyclooxygenase-2 inhibitors, we conclude that, although high (supra-pharmacologic) concentrations of these drugs may induce some in vitro immunomodulatory effects on the innate immune system, the findings are of doubtful predictive significance with respect to human health implications. | 18,958,669 |
Preclinical immunogenicity testing for recombinant therapeutic proteins. | The assessment of the immunogenicity of recombinant therapeutic proteins (RTPs) has received more attention in the past 4 years than in the previous 20 years. The induction of clinically adverse events in RTP-treated patients and the subsequent measurement of antibodies to those RTPs has challenged the scientific community to re evaluate the methods and techniques used for determining the immunogenic potential of therapeutic proteins. One preclinical strategy for determining the relative immunogenicity of RTPs is the use of a comparative hyperimmunization technique in animals that optimizes an immunological response. This approach has utility for analyzing the immunogenic potential of different formulations as well as for potential adverse effects. The hyperimmunization model may also provide a source of antisera specific to the RTP that can be used during selection of the appropriate assay technique(s) and conditions for measuring the immune response. Solid- or liquid-phase, affinities and the frequency of washes, isotypes, and sensitivities are key parameters that have become the focus of assay development techniques. The techniques that will be discussed include enzyme-linked immunoassays, surface plasmon resonance (Biacore), and capillary electrophoresis. | 18,958,675 |
A systematic analysis of the effect of corn, wheat, and poultry dusts on interleukin-8 production by human respiratory epithelial cells. | The objective of this study was to determine the inflammatory response initiated by various organic dusts by measuring in vitro interleukin-8 (I-8) production from transformed respiratory epithelial cells after dust exposure. To accomplish this objective, the following specific tasks were performed: 1) dust samples were collected from grain farms, grain storage facilities, and poultry houses and their endotoxin levels were determined; 2) A549 transformed respiratory epithelial cells were exposed to 0, 10, 100, or 1,000 mug/ml of organic dust or lipopolysaccharide (LPS); and, 3) production was measured using enzyme-linked immunosorbant assays (ELISAs). The results indicate that LPS induced at all concentrations. All dust types (corn, wheat, and poultry) induced at significantly higher levels than control and at significantly different levels between dust types. Overall there was an increasing trend of elevated production as the concentration of dust exposure was increased except at the highest concentration where IL-8 levels decreased and more cell death was observed. Corn dust exposure induced IL-8 that increased with increasing dust concentration and correlated with increasing amounts of LPS in the corn dust samples. However, IL-8 production in response to wheat dust was inversely related to LPS concentration suggesting that other factors besides LPS are present in the dust that are responsible for induction of IL-8 production. This study indicates that IL-8 induction varies between agricultural dust types and does not always correlate with endotoxin levels present in the dust. Therefore, other factors may be present in the dust that also elicit the immune response after exposure. | 18,958,683 |
The Relationship Between Noncoplanar PCB-Induced Immunotoxicity and Hepatic CYP1A Induction in a Fish Model. | Abundant literature exists demonstrating the immunomodulating effects of polychlorinated biphenyls (PCBs). To date, most of the research has focused on dioxin-like coplanar PCB congeners because of their high affinity for the aryl hydrocarbon receptor (AhR) and cytochrome P450-inducing capability. For this study, the impact of two structurally different PCB congeners on the immune responsiveness of bluegill sunfish (Lepomis macrochirus) was examined to evaluate the immunotoxic potential of each congener (as separate entities) and to relate effects on immune function with hepatic CYP1A induction. Fish received a single intraperitoneal injection of the: coplanar congener, PCB 126 (0.01 or 1.0 mug/g BW); noncoplanar PCB 153 (5.0 or 50.0 mug/g BW); or, the corn oil vehicle. PCB-induced effects on innate and cell-mediated immune parameters, and on hepatic CYP1A protein induction were evaluated in fish sacrificed 1, 3, 7, 14 or 21 days post-injection. In the absence of CYP1A induction, PCB 153 increased kidney phagocyte-mediated superoxide production 3 d post-injection, and at the highest dose suppressed B- and T-lymphocyte proliferation after 3 and 7 days, respectively. Treatment of fish with PCB 126 had no effect on oxyradical production, but altered B-lymphocyte proliferation after 1 day, also in the absence of CYP1A induction. Hepatic CYP1A was only induced in fish exposed to the highest PCB 126 dose; protein induction appeared at 3 d post-injection and persisted for up to 21 days. Taken together, these results demonstrate that exposure to different PCB congeners can alter immune function in the absence of CYP1A induction, suggesting that mechanisms other than the AhR pathway may play a role in PCB-induced immunotoxicity, particularly for the noncoplanar congeners. | 18,958,684 |
Development and Validation of a Quasi-Quantitative Bioassay for Neutralizing Antibodies Against CP-870,893. | The human monoclonal antibody CP-870,893 is a CD40 receptor agonist currently being developed for the treatment of cancer. A bioassay to measure neutralizing antibodies (Nab) to CP-870,893 in 5% human serum matrix was developed and validated utilizing the Daudi cell line and flow cytometric detection. Additionally, samples from CP-870,893 treated cynomolgus monkeys were analyzed in the bioassay and compared to results obtained using a competitive receptor-binding (CRB) Nab immunoassay to determine if the CRB assay may be used in place of the bioassay. Treatment of Daudi cells for 2 d with CP-870,893 leads to a concentration-dependent increase in CD54 cell surface expression. The presence of antidrug Nab attenuates CP-870,893 binding to CD40 and the induction of CD54. An anti-idiotype monoclonal antibody (Mab) and a monkey sera pool were identified as positive controls for neutralization of CP-870,893. During development, it was observed that the assay robustness was altered by culture media and FBS substitutions. For validation the following parameters were established: cutpoint factors in the presence (0.779) and absence (1.282) of 50 ng/ml CP-870,893, linear region of the concentration-response (1-100 ng/ml CP-870,893), intra- and inter-assay precision (CV </= 25%), specificity and recovery (+/-25%), sensitivity ( approximately 500 ng anti-idiotype Mab per ml serum), technician to technician ruggedness (CV </= 25%), and stability (positive control, CD54 labeling, and cell line). A concentration dependent increase in CP-870,893 neutralization was observed in a 3-mo toxicity study in monkeys using both the Bioassay and CRB assay (R(2) = 0.94) suggesting the CRB Nab assay may be a suitable alternative to a bioassay. Based on the precision, specificity, sensitivity, and robustness, the validated bioassay is suitable for quasi-quantitative analysis of neutralizing anti-CP-870,893 antibodies in human serum. | 18,958,696 |
Mechanisms of Signal Transduction from Receptors of Type I and Type II Cytokines. | Cytokines play pivotal roles in regulation of immune responses. Signaling proteins involved in cytokine signal transduction pathways can be potential targets of toxins causing aberrant immune responses. Binding of cytokines to their specific receptors induces activation of signal transduction pathways. In this review, an overview of the cytokine/cytokine receptor system, signaling pathways activated by cytokine receptors, their regulation mechanisms, pathological conditions caused by aberrant cytokine signaling, and issues to be elucidated in the near future is provided. | 18,958,714 |
Changes in gene expression induced by tienilic Acid and sulfamethoxazole: testing the danger hypothesis. | Tienilic acid (TA) was withdrawn due to idiosyncratic hepatotoxicity. Two hypotheses for the mechanisms of idiosyncratic reactions are the hapten and danger hypotheses, which are not mutually exclusive. Both human CYP 2C9 and rat CYP 2C11 metabolize TA to a reactive metabolite that was reported to bind exclusively to these enzymes. TA-Induced liver toxicity is associated with antibodies against CYP 2C9, thus TA appears to act as a hapten. However, if the binding were limited to CYP 2C, it is unlikely that this would lead to significant cell stress. If TA does not cause cell stress it would suggest that acting as a hapten is sufficient to induce an idiosyncratic reaction. To test whether TA can cause cell stress rats were dosed with TA and hepatic gene expression was profiled at 6 and 24 hr after drug administration. TA induced changes in genes involved in oxidative stress (aldo-keto reductase, glutathione-S-transferase, thioredoxin reductase, epoxide hydrolase), inflammation (IL-1beta, interferon regulatory factor 1, macrophage stimulating protein 1), cytotoxicity (caspase-12), and liver regeneration (p27(Kip1), DUSP6, serine dehyratase, spectrin beta II, inhibin beta(A)). These data support the hypothesis that danger signals in the form of cell-stress may be involved in initiating the immune response observed in TA-induced toxicity. In separate experiments, we examined the changes in gene expression induced in mice by sulfamethoxazole, which also causes idiosyncratic reactions. Sulfamethoxazole is an aromatic amine, and aromatic amines in general are associated with idiosyncratic drug reactions. They form reactive metabolites that both act as electrophiles and can redox cycle; therefore, it was assumed that sulfamethoxazole would cause some type of cell stress, the only question was what changes in mRNA expression would occur. In contrast to expectations, no changes induced by sulfamethoxazole could easily be interpreted as a danger signal. These data are presented together because they are the opposite of the expected results and convey a complex story. | 18,958,736 |
Reproductive health information for young women in Kazakhstan: disparities in access by channel. | This study explores young women's reliance on reproductive and sexual health information channels, examining the relationship between information sources and reproductive health knowledge. Utilizing 1995 and 1999 Kazakhstan Demographic and Health Surveys, we investigate access to reproductive health knowledge among young women (ages 15-24) during a key period in the development of wide-scale reproductive health programs in Kazakhstan. Despite reproductive health campaigns throughout the 1990s, we find consistently high proportions of young women without family planning information access. Among young women with access to information, few received information from channels most strongly linked to knowledge and behavioral changes (family and medical professionals). Mass media sources and peer information networks remained the most often utilized channels. Urban residence, non-Kazakh ethnicity, older age (20-24), and higher education significantly increased the odds of accessing family planning information among young Kazakhstani women, and these same factors were especially important in terms of the relative odds of accessing medical and parental channels. While overall contraceptive knowledge and prevalence rose in Kazakhstan during the 1990s, we find knowledge varied by the information channel accessed. Findings also indicate that young women, regardless of marital status, possessed consistently low levels of reproductive health knowledge at the decade's end. | 18,958,780 |
[Immune monitoring in SIRS and sepsis based on the PIRO model]. | Sepsis is a life-threatening disease characterized by a complex interaction between pathogens and the immune system. The analysis of immune parameters in patients with sepsis or at risk for sepsis may help to identify predisposing factors and infection-specific reaction patterns, as well as to monitor the current functional state of the immune system. This may lead to personalized therapeutic strategies for improving outcome in sepsis. Based on the PIRO model (predisposition, insult, response, organ dysfunction), a pathophysiologically-oriented concept for the development of a new sepsis classification, this article reviews currently used and new parameters for immunomonitoring in SIRS (systemic inflammatory response syndrome) and sepsis. | 18,958,829 |
Echo-rich and echo-poor periportal cuffing: pole position for inflammatory bowel diseases. | To determine the prevalence of echo-rich and echo-poor periportal cuffing in patients from a German tertiary referral hospital and correlate ultrasonographic findings with clinical data. From April 2002 till April 2008 about 10 500 abdominal examinations were performed by a single physician in our interdisciplinary ultrasound unit. During this time, n = 100 patients (62 male/ 38 female) with periportal cuffing of the liver were detected qualifying for the retrospective study design. Echomorphology of periportal cuffing was evaluated and clinical diagnoses of the underlying diseases were clustered in four main groups: Liver diseases, haematological diseases, bowel diseases and others. Furthermore, liver function tests and body mass index were determined. The mean age of the patients was 57.06 years (SD +/- 19.47). Mean body-mass-index was 24.76 kg/m (2) (SD +/- 4.28). Periportal cuffing was echo-poor in n = 9 (9 %) and echo-rich in n = 91 (91 %). Echo-poor periportal cuffing was significantly more often associated with malignant diseases as compared to echo-rich periportal cuffing (78 vs. 36 %) (p < 0.025). Liver diseases (n = 33) were malign n = 10 (10 %), autoimmune n = 8 (8 %), infectious n = 8 (8 %) and cholestatic n = 7 (7 %). Bowel diseases (n = 34) originated from the upper gastrointestinal tract n = 7 (7 %), lower gastrointestinal tract n = 21 (21 %) and the pancreas n = 6 (6 %). Haematological disorders (n = 15, 15 %) were chronic myeloproliferative n = 2 (2 %), lymphoma n = 8 (8 %), leukemia n = 4 (4 %) and miscellaneous n = 1 (1 %). Other diseases accounted for 18 (18 %) of cases. Aspartat-aminotrasferase (AST) and alanin-aminotransferase (ALT) were elevated in 39 patients (40 %) and 34 patients (35 %), respectively. Total bilirubin was elevated in 35 patients (36 %). Alkaline phosphatase (AP) was detected above normal range in 49 patients (50 %) whereas g-glutamyl-transferase was elevated in 58 patients (59 %). Periportal cuffing of the liver is an extremely rare ultrasonographic phenomenon with a prevalence of approximately 0.95 % in our unit. Echo-rich periportal cuffing occurs more frequently than echo-poor periportal cuffing. The majority of echo-poor periportal cuffing is associated with malignant disorders, in particular haematological diseases, whereas echo-rich periportal cuffing is most frequently seen in inflammatory bowel disease patients. | 18,958,833 |
Insulin therapy in acute coronary syndromes: an appraisal of completed and ongoing randomised trials with important clinical end points. | Insulin therapy was first proposed as an adjunctive therapy in patients with acute coronary syndromes (ACS) in the 1960s. Since then, numerous randomised clinical trials have been conducted to determine the efficacy and to define the role of insulin therapy in ACS. This review will discuss: 1) completed trials of insulin therapy in ACS, including both glucose-insulin-potassium (GIK) approaches and non-GIK approaches; 2) trials of insulin therapy in critically ill non-ACS patients and the lessons from these trials that can be applied to trials of insulin in ACS patients; and 3) a summary of ongoing and planned trials of insulin in ACS patients. | 18,958,837 |
Implications of abnormal glucose metabolism in patients with coronary artery disease. | Abnormal glucose metabolism and type 2 diabetes mellitus (T2DM) are becoming increasingly common. It has been recently confirmed that the period of time prior to the development of diabetes, when patients have impaired glucose tolerance, may also predispose them to increased cardiovascular risk. Therefore prevention and management of T2DM and its antecedents must have high priority when allocating healthcare resources. The present review summarises some information on detection, management and treatment of abnormal glucose metabolism in patients with established coronary artery disease, highlighting the importance of early detection of abnormal glucose metabolism in order to prevent the progression of prediabetes to T2DM and to delay the occurrence of those macrovascular and microvascular complications that impair quality of life and diminish survival. | 18,958,838 |
Dielectric cell separation of fine needle aspirates from tumor xenografts. | As an approach to isolating tumor cells from fine needle biopsy specimens, we investigated a dielectric cell preparation method using an in vivo xenographic tumor model. Cultured human MDA-MB-435 tumor cells were grown as solid tumors in nude mice and fine needle aspiration biopsies were conducted. Biopsied cells were suspended in sucrose medium and collected on slides patterned with microelectrode arrays (electrosmears) energized by electrical signals in the range 10 to 960 kHz. The unlabeled cells adhered to characteristic regions of the slides in accordance with their morphology as a result of dielectric forces. Tumor cells were trapped between 40 and 60 kHz and were separated according to whether they were mitotic, large and complex, or small. Damaged tumor cells were captured at between 60 and 120 kHz; granulocytes between 70 and 90 kHz; lymphocytes between 85 and 105 kHz; healthy erythrocytes between 140 and 180 kHz, and damaged erythrocytes above 180 kHz. Using intrinsic cell characteristics, the electrosmear presented cell subpopulations from fine needle aspiration biopsy specimens in a manner that is compatible with automated slide-based analysis systems. The approach has the potential to facilitate the analysis of the role of cell subpopulations in disease. | 18,958,846 |
Nanoparticle formulations in pulmonary drug delivery. | The advent of nanotechnology has reignited interest in the lungs as a major route of drug delivery for both systemic and local treatments. The large surface area of the lungs and the minimal barriers impeding access to the lung periphery make this organ a suitable portal for a variety of therapeutic interventions. Nanoparticles provide new formulation options for both dispersed liquid droplet dosage forms such as metered dose inhalers and nebulizers, and dry powder formulations. Nanoparticle formulations have many advantages over traditional dosage forms, such as enhanced dissolution properties and the potential for intracellular drug delivery. Specifically, pure drug nanoparticles, polymeric nanoparticles, polyelectrolyte complexes, and drug-loaded liposomes offer some encouraging results for delivering drugs to and through the lungs. Methods are also being investigated to produce nanoparticles with properties suitable for improving access to the peripheral lung. Traditional techniques such as spray drying and grinding, and more recent advances in supercritical fluid extraction, precipitation, and solvent extraction have been employed to produce nanoparticle formulations for pulmonary delivery. Here, the benefits of nanoparticle formulations and current progress are compared in light of the practical encumbrances of producing formulations, and possible toxicological effects of these materials. | 18,958,847 |
Fabrication of skeletal muscle constructs by topographic activation of cell alignment. | Skeletal muscle fiber construction for tissue-engineered grafts requires assembly of unidirectionally aligned juxtaposed myotubes. To construct such a tissue, a polymer microchip with linearly aligned microgrooves was fabricated that could direct myoblast adaptation under stringent conditions. The closely spaced microgrooves fabricated by a modified replica molding process guided linear cellular alignment. Examination of the myoblasts by immunofluorescence microscopy demonstrated that the microgrooves with subcellular widths and appropriate height-to-width ratios were required for practically complete linear alignment of myoblasts. The topology-dependent cell alignment encouraged differentiation of myoblasts into multinucleate, myosin heavy chain positive myotubes. The monolayer of myotubes formed on the microstructured chips allowed attachment, growth and differentiation of subsequent layers of linearly arranged myoblasts, parallel to the primary monolayer of myotubes. The consequent deposition of additional myoblasts on the previous layer of myotubes resulted in three-dimensional multi-layered structures of myotubes, typical of differentiated skeletal muscle tissue. The findings demonstrate that the on-chip device holds promise for providing an efficient means for guided muscle tissue construction. | 18,958,861 |
IL-4 inhibits VLA-4 expression on Tc1 cells resulting in poor tumor infiltration and reduced therapy benefit. | We and others have previously demonstrated that IL-4-dependent Tc2 are inferior to Tc1-effector CD8+ T cells in regulating tumor progression in vivo. This functional disparity relates, in part, to the comparatively poor ability of Tc2 to migrate into diseased tissues. We now show that IL-4 treatment of committed Tc1 cells promotes the selective loss in the expression of very-late antigen (VLA)-4, without impacting the Tc1 cytokine production profile, cytotoxic activity, or expression of alternate cell surface markers. Down-regulation of VLA-4 expression on Tc1 cells was unique to treatment with IL-4 (i.e. Tc1IL-4) and did not occur in the presence of the Type-2 cytokine IL-13 or the regulatory cytokines IL-10 or TGF-beta. Notably, the inhibitory effects of IL-4 on Tc1 expression of VLA-4 could be blocked by the presence of IL-12, but not IFN-gamma. Predictably, Tc1IL-4 (but not Tc1 control) cells adhere poorly to plate-bound VCAM-1-Fc fusion protein and fail to be co-stimulated by VCAM-1 in vitro. They were also markedly impaired in their ability to traffic into intracranial melanoma lesions after adoptive transfer, yielding inferior therapeutic benefit to tumor-bearing mice. These results suggest a novel suppressive mechanism for IL-4 that limits Tc1 efficacy via preventing their recruitment into tumors. | 18,958,887 |
Risk perception, risk management and vulnerability to landslides in the hill slopes in the city of La Paz, Bolivia. A preliminary statement. | The article begins by describing the difficult living conditions of many people in the hill slopes (laderas) of La Paz, Bolivia, demonstrating that they are exposed to a combination of natural and social hazards. It shows that residents, community leaders and city planners tend to underestimate or deny risk, with important consequences for risk management, such as a failure to raise risk awareness. The article then proposes some hypotheses to explain risk perceptions in La Paz, discarding the usual single-approach interpretations and suggesting instead more nuanced theoretical explanations to account for why people build their homes in such hazardous environments. | 18,958,908 |
Prophylactic intratubal injection of methotrexate after linear salpingostomy for prevention of persistent ectopic pregnancy. | To examine the efficacy of local methotrexate (MTX) administration following linear salpingostomy for tubal pregnancy in the prevention of persistent ectopic pregnancy (PEP). Patients who underwent a laparoscopic linear salpingostomy between January 1996 and December 2006 were enrolled in the study. Patients who were assigned to the prophylaxis group were administered MTX (50 mg) into the tubal wall in the vicinity of the lesion immediately following linear salpingostomy (n=41). Patients who were treated without MTX were assigned to the control group (n=40). Serum human chorionic gonadotrophin levels were followed in both groups postoperatively once every 3 days until they became undetectable. The incidence of PEP was compared between the two groups. Persistent ectopic pregnancy occurred in seven patients (17.5%) in the control group compared with zero patients in the prophylaxis group (P<0.05). There were no side-effects attributable to MTX in the prophylaxis group. A single prophylactic intratubal injection of MTX following laparoscopic linear salpingostomy is a safe and effective regimen for the prevention of PEP. | 18,958,931 |
[Neurological and psychiatric disorders in primary hyperparathyroidism: the role of parathyroidectomy]. | The clinical presentation of primary hyperparathyroidism (pHPT), previously constantly characterized by bone and renal diseases, has been changing during last years. Several Studies report psychic and behavioural symptoms mostly vague and aspecific, particular in elderly patients, such as asthenia, anxiety, depression, irritability, mood swings, amnestic and cognitive disturbances, severe psychosis. In case history hereby reported 11.8% of the patients affected by pHPT (16 out of 136 cases operated from 1983 to October 2006) who underwent to parathyroidectomy, presented only neuro-cognitive and/or psychiatric symptoms. A relevant association has been found between clinical presentation and age: patients showing neuro-cognitive and psychiatric disturbances were older compared to those suffering from the classical bone and kidney disease. No significant correlation neither with serum calcemia nor with PTH serum levels and severity of the symptomatology was demonstrated A statistically significant reduction of the anxious-depressive disturbances one month post surgery has been found (p < 0.05), and an improvement, though not significant, of the neuro-cognitive and psychiatric alterations was registered (p > 0.1). The Authors believe neuro-cognitive or psychic manifestations is not to be neglected, mainly in geriatric patients: frequently the aspecific symptomatology is not referred as hypercalcemia due to pHPT Neuro-psychic symptomatology should be considered an indication for surgical treatment. | 18,958,962 |
A self-determination theory perspective on the role of autonomy in solitary behavior. | People are often seen as social creatures and, consequently, solitary behaviors are often cast in a negative light. However, the authors hypothesized that the act of spending time alone is not necessarily related to negative outcomes; rather, individuals' motivation for doing so plays a key role. On the basis of self-determination theory (E. L Deci & R. M. Ryan, 2000; R. M. Ryan & E. L. Deci, 2000), the authors predicted and found that when individuals spend time alone in a volitional and autonomous manner, they counterintuitively report lower levels of loneliness and higher levels of well-being. | 18,958,983 |
[Cytological observation of anther abortion and starch distribution of a cytoplasm male sterile pepper (Capsicum annum L.)]. | A cytoplasm male sterile pepper (Capsicum annum L.) was examined using cytochemical method to study its pollen abortion. Thick sections of both anthers of male sterility line 8214A and its maintainer 8214B at different stages were stained using Periodic Acid-Schiff's (PAS) reaction to detect starch distribution. Anther structure and starch distribution in both anthers of male sterility and maintainer line were similar before the meiosis of microspore mother cells. After meiosis, the size of tapetal cells of fertile anthers of maintainer line increased and became high vacuolation. Abundant small starches appeared in the connective cells from tetrad stage to early stage of microspore development. At the late stage of microspore, the tapetal cells began to degenerate and the starches in the connective cells became large. Bi-cellular pollen synthesized starches after the large vacuole of vegetative cell disappeared, and abundant starches were stored in the mature pollen. In the anthers of male sterile line, meiosis of microspore mother could occurred and the tetrads could be formed in the locule, but the tetrads were extruded together because the locule could not enlarge its space. Finally, the tetrad microspores degenerated. The development of vascular tissue of the sterile anthers was normal and abundant starches were stored in the connective cells, which suggested that the function of plant transporting polysaccharide into anther was normal but tapetum could not transport the polysaccharide into locule. According to our result, the pollen abortion occurred in the tetrad stage and the abnormal development of tapetal cells might be the reason which induced tetrad microspore abortion in this male sterile pepper. | 18,959,002 |
[The role of mitochondrial permeability transition pore in transmembrane Ca2+-exchange in mitochondria]. | Ca2+-uptake accompanied with mitochondrial permeability transition pore (MPTP) opening is studied in rat liver mitochondria. In conditions of MPTP opening, as well as in conditions of MPTP blockage by cyclosporine A (CsA), Ca2+-uptake in mitochondria is counterbalanced by proton efflux into incubation medium. Independent of MPTP opening, observed stoichiometry of this exchange is 1Ca2+ : 1H+. MPTP opening dramatically decreases Ca2+-uptake in mitochondria: from approximately 400 nmol/mg protein in the presence of CsA to approximately 80-100 nmol/mg protein due to the increased mitochondrial membrane permeability. In the absence of CsA Ca2+-uptake is accompanied by the insensitive to Ca2+-uniporter blocker, ruthenium red (RR), release of Ca2+ from mitochondria which corresponds to as well RR-insensitive, but sensitive to CsA uptake of H+ into mitochondrial matrix. This calcium-proton exchange resulting from MPTP opening is observed only when Ca2+ uptake into matrix exceeds some basal level. The data are consistent with an assumption that, contrary to Ca2+-uniporter, MPTP has its own proton conductance. MPTP opening provides exchange of Ca2+ between mitochondria and medium which is coupled to the counterflow of protons into matrix space. Obtained data elucidate the physiological role of MPTP as regulatory mechanism for control of Ca2+-uptake level and intramitochondrial pH. | 18,959,026 |
[Influence of different sources of carbon and nitrogen on the biosynthesis of proteolytic complexes by Bacillus circulans 693, Bacillus sp. 27 and Yarrowia lipolytica 2061 strains]. | The influence of different factors on the biosynthesis of extracellular proteolytic complexes by strains-producers Bacillus circulans 693, Bacillus sp. 27 and Yarrowia lipolytica 2061 at submerged cultivation has been investigated. It has been shown that ammonium hydrocarbonate and gelatin with glucose were optimum carbon and nitrogen sources for synthesis of proteolytic activity of B. circulans strain 693, gelatin with arabinose--for Bacillus sp. 27, gelatin and glycine with sorbose--for Y. lipolytica 2061. It has been established that the cultivation of producers on optimal sources of carbon and nitrogen increased protease activity of cultural liquid of B. circulans 693 3.8 times, Bacillus sp. 27--2.7 times, Y. lipolytica 2061--3.4 times. It has been found that the usage of different protein substrates in cultural medium permitted to obtain the proteolytic enzymes with various specificity with respect to globular and fibrillar proteins. | 18,959,038 |
[Peculiarities of tricarboxylic acid cycle in the myocardium of adult and old rats in the case of immobilization stress]. | Indices showing Krebs cycle functioning in the hearts of adult and old rats subjected to 30-minutes immobilization were studied in order to find out the causes of age-related increase of heart sensitivity to stress. The studies have shown that compensatory changes of energy metabolism promoting limitation of stress-induced decrease of energy supply of the heart muscle took place in the myocardium mitochondria in adult and old rats during immobilization stress. The changes are associated with maintenance of high rate of redox reactions in the Krebs cycle and increase of myocardium respiration in old rats, and with an increase of the FAD-dependent processes in tissue respiration in adult rats. | 18,959,040 |
[Today's tests of vestibular function]. | New tests of the vestibular function have been developed. They should help to explain some clinical situations. The paper describes 3 tests today used routinely in most centers, with a special emphasis on the sign of Halmagyi, or head impulse test. It is designed to detect deficits of the semicircular canal function in the horizontal and vertical directions as well. It is feasible without any equipment. However, an infrared camera connected to a computer increases markedly its sensitivity. | 18,959,075 |
[Evaluation of the pediatric airway]. | Obstruction is the most common manifestation of airway pathology by children. The practitioner may be confronted to this relatively frequent problem. The pathology spectrum is very wide, and includes congenital malformations, infections, traumas, and tumours. The most frequent etiology of congenital upper airway obstruction is laryngomalacia. Adenotonsillar hypertrophy is by far the most common cause of obstruction by children aged 2 - 7 years. The medical history and the clinical examination allow to determine the degree of emergency, to orientate the diagnosis, and to decide when to refer the patient to a specialist. Endoscopy is the gold standard examination for diagnosis. In some cases, others investigations, such as radiological examinations, may be necessary. | 18,959,076 |
The emergency room--analysis and evaluation of an organizational model. | The purpose of the emergency room is to treat critically ill patients and to prevent cardiac arrest in patients presenting with signs of physiological instability. This study has two main aims: 1) to describe the organizational model of the emergency room of Hospital Pedro Hispano based on 'chain of survival' principles; 2) to report an outcome analysis after the first year's operation with this organizational model. Patients arriving at the emergency department of Hospital Pedro Hispano are processed by the Manchester Triage System. Patients presenting in a critical condition are coded red and immediately admitted to the emergency room. Patients classified as less critical but whose condition may worsen, with signs of physiological instability, are also admitted to the emergency room. This reflects the operating principles of the emergency room based on the prevention of cardiac arrest. All patients admitted to the emergency room have an emergency room chart, on which this study is based. Between May 1 2005 and April 30 2006, 1014 patients were admitted to the emergency room. Sixty-five percent of them were aged over 60 years. Altered consciousness was the most frequent reason for admission (17%), followed by respiratory failure (13%) and tachycardia (11%). Fifty-one patients (5%) were admitted after cardiac arrest. Sixty-six patients (7%) died in the emergency room, 57% of whom were admitted following cardiac arrest and 17% after shock of any etiology. A further 189 patients died during the course of their hospital stay after being discharged from the emergency room to other wards, which represents an overall mortality of 25%. Prevention and treatment of causes of cardiac arrest were the main reason for admission to the emergency room (altered consciousness, respiratory failure and tachycardia). Cardiac arrest was not among the main reasons for admission. However, when it occurs it has very high mortality; in the present study it was responsible for 5% of admissions and 53% of mortality. This organizational model may contribute to better use of resources as it enables re-orientation of patients to appropriate levels of care. | 18,959,087 |
Construction of recombinant adenovirus co-expression vector carrying the human transforming growth factor-beta1 and vascular endothelial growth factor genes and its effect on anterior cruciate ligament fibroblasts. | Remodeling of the anterior cruciate ligament (ACL) graft usually takes longer than expected. Gene therapy offers a radical different approach to remodeling of the graft. In this study, the internal ribosome entry site (IRES) sequence was used to construct a new recombinant adenovirus which permits co-expression of transforming growth factor-beta1 (TGFbeta1) and vascular endothelial growth factor 165 (VEGF165) genes (named Ad-VEGF165-IRES-TGFbeta1). We investigated the effects of the new adenovirus on the migration of and matrix synthesis by ACL fibroblasts. Adenoviral vector containing TGFbeta1 and VEGF165 genes was constructed. ACL fibroblasts were obtained from New Zealand white rabbits. After ACL fibroblasts were exposed to Ad-VEGF165-IRES-TGFbeta1, the expression of VEGF165 and TGFbeta1 proteins were assessed by enzyme-linked immunosorbent assay (ELISA) and Western blotting analysis. Bioassay of VEGF165 and TGFbeta1 proteins were assessed by Western blotting analysis. Proliferation and migration of ACL fibroblasts were assessed by in vitro wound closure assay. Gene expression of collagen type I, collagen type III, and fibronectin mRNA among matrix markers were assessed by real-time PCR. The results showed the successful construction of a recombinant co-expression adenovirus vector containing TGFbeta1 and VEGF165 genes. Co-expression of TGFbeta1 and VEGF165 can induce relatively rapid and continuous proliferation of ACL fibroblasts and high gene expression of collagen type I, collagen type III, and fibronectin mRNA among matrix markers. Co-expression of TGFbeta1 and VEGF165 genes has more powerful and efficient effects on the migration of and matrix synthesis by ACL fibroblasts. | 18,959,121 |
[Chronic suppurative inflammation of the middle ear in children]. | Chronic suppurative inflammation of the middle ear (HGO) in children represents one of the most frequent infections in childhood, even in children from developed industrial countries. We can distinguish two types of chronic suppurative inflammation: first--HGO without cholesteatoma and second HGO with cholesteatoma. The objective of the paper was to point out the characteristics of chronic suppurative inflammation of the middle ear in children and possible methods of treatment. From 2000 to 2005, our retrospective study involved 92 children, aged 2 to 16 years, treated for chronic suppurative inflammation of the middle ear and subsequent otogenic complications. The diagnosis was established based on clinical symptoms, otoscopic and otomicroscopic findings. Treatment included the removal of the pathological process, reconstruction of the hearing chain and prevention recurrence. We performed 111 surgical interventions. Children were divided into two groups: in the first group, we performed 56 surgical interventions in 48 children diagnosed with chronic suppurative otitis without cholesteatoma, and in the second group we performed 55 surgical interventions in 44 children who were diagnosed with chronic otitis with cholesteatoma. In the first group we performed mastoidectomy in 17 (32.5%) children, mastoidectomy and posterior aticotomy in 5 (9.5%), miringoplasty in 22 (35.8%), timpanoplasty type II in 5 (9.5%), timpanoplasty type III in 3 (5.6%) and timpanomastoidectomy in 4 (7.1%) children. In the second group, consisting of children diagnosed with cholesteatoma of the middle ear, we performed 47 first act surgeries, using closed technique in 17, and open in 30 cases. We performed timpanoplasty type III in 17 (30.9%) and timpanomastoidectomy in 17 (30.9%), and timpanoplasty type II in 9 (16.4%), timpanoplasty type IV in 10 (18.2%) and mastoidectomy in 2 (3.6%) children. In the group treated by closed surgical technique recurrence occurred in 5 (29.4%), and in those treated by open technique in 3 (10.3%). Two children had bilateral cholesteatoma. Further research should be directed toward the identification of different types of factors and pathogenesis of HGO. Treatment of this decease is still considered controversial. Hinolon drops could represent a promising option in the treatment of HGO. The main objective in the treatment of cholesteatoma should be the improvement of the open technique to prevent retraction pockets, decrease of the rate of residual or atelectatic process and the improvement of hearing results. | 18,959,168 |
Two new species of Perichaena (Myxomycetes) from arid areas of Russia and Kazakhstan. | Two new myxomycete species from dry steppe and desert communities of the Caspian Lowland (Russia) and central Kazakhstan are described and illustrated. They are placed tentatively within genus Perichaena, which does include species with a reduced capillitium and single-layered peridium. Both species were found repeatedly in moist chamber cultures; P. heterospinispora appeared on leaf litter and twigs, whereas P. polygonospora occurred on leaf litter and weathered dung of rodents. Both species have spore ornamentation that is unique for members of genera Licea and Perichaena. The spore ornamentation of the first species includes scattered large, pyramid-like spines 0.9-1.2 microm high that sometimes have enlarged ends. Among these spines the spore surface is covered by evenly and densely distributed warts that are visible only by SEM. The second species is characterized by angular spores with a coarse network of rounded ridges. The areas among these ridges bear scattered composite warts 0.3-0.5 microm high that sometimes coalesce to form clusters but more often are distributed evenly and densely and are visible only by SEM. The stability of the taxonomic characters of both species was confirmed by several collections from different regions obtained in 2 y. The morphology of the fructifications of the two myxomycetes was examined with both scanning electron and light microscopy, and micrographs of all relevant features are presented. | 18,959,166 |
[Score system--potential uses and application in the assessment of results in Colles' fractures]. | Colles'fractures are the most common fractures of the human skeleton, especially in winter and in menopausal women. The objective of the paper was to provide an overview of the potential uses of the Gartland-Werley (G-W) scoring system, that is, of its elements (residual deformities, subjective discomfort, objective discomfort and complications) in assessing the results of the Colles' fractures treatment; as well as to determine which of these elements--and to what extent--have an impact on the final result of the scoring system and what correlations exist within the G-W scoring system itself. Our paper included 102 patients suffering from Colles' fractures treated non-operatively with a minimum follow-up period of one year.The Gartland-Werley scoring system was used to assess the results of the non-operative treatment. The results, when applying the G-W score, were excellent in 40, good in 46, satisfactory in 14, and poor in 2 patients at the end of the assessment. The G-W score elements had the following percentages in the scoring results: residual deformities 15.38%, subjective discomfort 15.38%, objective discomfort (functional results) 43.58%, and complications 25.64%. The correlation analysis showed a statistically significant correlation of the residual deformities and the total G-W score (p < 0.01) at the level of subjective discomfort and total G-W score (p < 0.01), and between objective discomfort and total G-W score at the same level. Colles'fractures, as the most common fractures in humans, require a special approach and adequate assessment of final treatment results, because inadequate treatment results in the reduction of patients'daily activities and their ability to work. | 18,959,174 |
[The foreign particles injection induces stable hyaline cells differentiation in the hemolymph of the blowfly Calliphora vicina larvae]. | The stable hyaline cells (thrombocytoids precursors) are prevailing haemocytes type in young larvae of Calliphora vicina. Their concentration decreased significantly during the crop emptying and became completely absent in wandering larvae. However, the injection of foreign particles into the haemocoel induced evident increase in the number of stable hyaline cells by means of transformation from prohaemocytes within 24 h after the treatment. Maximum of hyaline cells concentration is achieved on the 2-3 day when the part of them starts to transform into prothrombocytoids. Injection of both abiotic (charcoal) and biotic (human erythrocytes) foreign particles exerts an identical effect. Puncture of the body wall, bacterial immunization and injection of saline did not induce hyaline cells appearance. In crop emptying larvae, the stable hyaline cells originate within the clusters of undifferentiated steam cells, i. e. prohaemocytes. After the completion of crop emptying in wandering and diapausing larvae, preliminary dedifferentiation of very young plasmatocytes may be also observed. It is suggested that specification of the stable hyaline cells is induced by thrombocytoids after engulfing of the injected foreign particles and forming of their agglutinates. | 18,959,187 |
[Activity of error-prone DNA polymerase iota in different periods of house mouse Mus musculus ontogeny]. | Analysis of incorrect activity of error-prone DNA polymerase iota in M. musculus ontogeny demonstrated considerable changes in its activity, which peaks in most organs during prenatal development and decreases in the adult body. We propose that the capacity of error-prone DNA polymerases to synthesize on damaged DNA regions is critical for the realization of rapidly changing genetic program in mammalian embryogenesis, which relieves the replication block and prevents cell death. | 18,959,202 |
The relation between perceived parent-created sport climate and competitive male youth hockey players' good and poor sport behaviors. | The authors examined achievement goal orientation (J. L. Duda & J. G. Nicholls, 1992), parental influence (M. L. Babkes & M. R. Weiss, 1999), and the parent-initiated motivational climate (S. A. White, 1996, 1998) in combination to broaden understanding of competitive male youth hockey players' (N = 259) perceptions of the parent-created sport climate and its relation to their self-reported good and poor sport behaviors (GPSB). Exploratory factor analysis revealed a multidimensional measure of GPSB. Multiple regression analyses indicated that athletes' GPSB were significantly predicted by different forms of parental influence. Canonical correlations revealed a complex picture of the contributions of goal orientation and the parent-created sport climate on boys' GPSB in youth hockey. Results expand knowledge of the influence that parents have in youth sport and emphasize the importance of understanding how children's interpretations of parental beliefs and behaviors affect their choices to engage in good and poor sport behaviors. | 18,959,221 |
[Effect of hypoxia on the content and stoichiometry of cytochromes in muscle of the gray mullet Liza aurata]. | The maintenance of the gray mullet Liza aurata under conditions of hypoxia (P(O2) 55-82 GPa) for 1-2 days led to a decrease of oxygen pressure in arterial blood by 47%, while in venous blood--by 28%. The mean muscle oxygen pressure decreased by 19.2%. The number of hypoxic and anoxic zones in muscle tissue decreased significantly, in particular in red muscle. The maintenance of the fish in hypoxic waters for 15 days led to a rise of the content of cytochromes in muscle and a qualitative readjustment of the mitochondrial respiratory chain manifested in an increase of the content of cytochromes a and a3 and a decrease of cytochrome b. In discussion, literature data are presented which support the described regularity. | 18,959,214 |
[Recent advances in the detection of human erythropoietin and human growth hormone doping]. | In the World Anti-doping Agency 2008 Prohibited List, the prohibited substances of S2 item are hormones and related substances, which are belonging to the endogenous biomacromolecules. How to identify the substances derived from endogenous secretion or exogenous administration is the main problem in doping control analysis and attracts more attention. The present report summarizes the main analytical strategies, including indirect blood tests and direct detection approaches developed to identify the presence of erythropoietin (EPO) and human growth hormone (hGH), which have wide pharmaceutical applications and thus been fully examined. The recent physico-chemical or immunoanalytical methodologies on the discrimination of recombinant and endogenous proteins are emphasized. | 18,959,238 |
[Screening, quantification and confirmation of beta-blockers in urine using gas chromatography-mass spectrometry]. | A method was developed to perform the screening, quantification and confirmation of the five beta-blockers, propranolol, carteolol, bisoprolol, esmolol, and sotalol, in human urine using gas chromatography-mass spectrometry (GC-MS). In sample preparation, conjugated and unconjugated beta-blockers in urine were extracted separately, and the extracts were combined. The extracts were derivatized with N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) and N-methyl-bis(trifluoroacetamide) (MBTFA). The optimal conditions of GC-MS were established, and the progresses of screening by selected ion monitoring (SIM) mode and confirmation by full scan (SCAN) mode were completed. At last, the quantification curves of the five beta-blockers in spiked urine were established by SIM mode. The limits of detection were 0.2 -1.0 ng/mL. Overall recoveries were 70.5% - 103.4%, and the relative standard deviations were lower than 15%. In addition, the method was successfully applied to the analysis of the positive urine of propranolol, and the urinary excretion curve was also established accordingly. It is significant to prohibit the abuse of beta-blockers in doping control. | 18,959,242 |
[Determination of three anabolic steroids by liquid chromatography-mass spectrometry]. | A high performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI/MS) was developed to screen and determine trenbolone, tetrahydrogestrinone and gestrinone in human urine. The urine sample was enzymatically hydrolyzed with beta-glucuronidase, then extracted with methyl tert-butyl ether. Chromatographic separation was performed on a Zorbax SB-C18 column (150 mm x 2.1 mm, 5 microm) with ammonium formate buffer (pH 3.5) and acetonitrile as mobile phase. Using positive electrospray ionization mode, the effect of different parameters from electrospray chamber was investigated. The limits of detection based on signal noise ratio of 3 were between 1 and 5 ng. The method can be applied in screening and confirmation of the anabolic steroids in doping control. | 18,959,243 |
[Distribution determination of nitrogen compounds in catalytic diesel oil using gas chromatography]. | The method for the separation and determination of nitrogen compounds in catalytic diesel oil using gas chromatography-nitrogen chemiluminescence detection (GC-NCD) was established. The effects of the flow rate of carrier gas and oven temperature on the resolution were studied. More than 80 nitrogen compounds (such as aniline, alkyl anilines, quinoline, indole, alkyl indoles, carbazole, alkyl carbazoles) in catalytic diesel oil were enriched using a Al2O3 column and identified based on the retention time of some pure nitrogen compounds and the retention index of nitrogen compounds on GC-NCD. The relative standard deviations of the peak areas of main nitrogen compounds in catalytic diesel oil were lower than 8%. The detection limit (S/N = 3) for nitrogen of carbzole was 1.0 mg/L under the chosen conditions. The linear range of nitrogen was 1.0 - 600 mg/L for each nitrogen compound. The correlation coefficient was more than 0.998. The recoveries of four nitrogen compounds (aniline, quinoline, indole, carbazole) in catalytic diesel oil were in the range of 89.5% - 99.8%. The method can be applied for the determination of each nitrogen compound in different catalytic diesel oils. | 18,959,246 |
[Analysis of organochlorine pesticides in buckwheat using pressurized liquid extraction and gas chromatography]. | Seven organochlorine pesticides (OCPs) in buckwheat were extracted by a homemade 24 cells auto-pressurized liquid extraction instrument (APLE) and then analyzed by gas chromatography with electronic capture detection. The optimal extraction condition was found to be 100 degrees C and 10 MPa for 5 min with acetone/n-hexane (1:1, v/v) as the extraction solvent. The extraction was performed twice for each sample to obtain complete extraction. The buckwheat was mixed with florisil and active carbon before filling into extraction cells. Concentrated sulfuric acid was used in clean up step of the extractant. The standard mixture of OCPs including alpha-benzene hexachloride (BHC), gamma-BHC, delta-BHC, p, p'-dichloro-diphenyl-dichloroethylene (p,p'-DDE), p,p'-dichloro-diphenyl-dichloroethane (p, p'-DDD), o, p-dichloro-diphenyl trichloro-ethane (o,p-DDT), p,p'-DDT was used for the identification and quantification in gas chromatographic analysis. The absolute recoveries of the 7 organochlorine pesticides were between 68%-126% with the relative standard deviations lower 14.7%. The detection limits were between 0.051 - 0.18 ng/g. The relative recoveries were as high as 116%-148% compared with Soxhlet extraction. It shows that the recoveries of APLE are much better than Soxhlet extraction, and the time of extraction for APLE is only about 15 min which is much less than conventional extraction methods. | 18,959,247 |
[Determination of 11 fatty acids and fatty acids methyl esters in biodiesel using ultra performance liquid chromatography]. | A method for the determination of 11 familiar components in biodiesel was developed using ultra performance liquid chromatography with evaporative light scattering detector (UPLC-ELSD). These components were oleic acid, methyl cis-9-octadecenoate, linoleic acid, methyl linoleate, stearic acid, methyl octadecanoate, methyl linolenate, palmitic acid, methyl hexadecanoate, erucic acid and myristic acid. The sample was dissolved in methanol after extraction from the products. The separation column was an Acquity UPLC BEH Phenyl C18 (100 mm x 2.1 mm, 1.7 microm) and the mobile phase was acetonitrile-water (3:1, v/v). An isocratic elution program was utilized for the separation. The flow rate was 0.3 mL/min and the column temperature was 40 degrees C. The parameters of ELSD were as follows: the plus was 80; the temperature of the drift tube was 45 degrees C; the eluant gas pressure was 172 kPa. The sample was detected by ELSD in only 5 min. The calibration curves of 11 components showed good linearity with the correlation coefficients greater than 0.997. In comparison with other methods, this method is simple, fast, and has a good separation efficiency. The fatty acids and fatty acid methyl esters were separated in one step, thus, the extent of reaction can be confirmed by the determination of their contents. This method can be routinely used for the determination of the fatty acids and fatty acid methyl esters in the reaction products and the final biodiesel. | 18,959,249 |
[Determination of quinoxyfen residue in foodstuffs of plant and animal origins by high performance liquid chromatography]. | A high performance liquid chromatographic (HPLC) method has been developed for the determination of quinoxyfen residue in various food matrixes including soybean, cauliflower, cherry, mushroom, wine, tea, honey, pork liver, chicken and eel. The analyte was extracted by ethyl acetate, and then purified with aminopropyl solid phase extraction (NH2 SPE) cartridge. Post-extraction gel permeation chromatography (GPC) was used for animal (except honey) and fishery products prior to NH2 SPE cleanup. The average recoveries and relative standard deviations (RSDs) for the analysis of all samples fortified in the range of 0.010 - 5.0 mg/kg were in the ranges of 82% - 96% and 3.2% - 11.8%, respectively. Good linearity was obtained in the concentration range from 0.050 to 50.0 mg/L. The limit of detection was 0.010 mg/kg. The proposed method was successfully applied to the analysis of quinoxyfen residue in various food samples. | 18,959,250 |
[Management of inverted papilloma in frontal sinus]. | To introduce the experience of management of inverted papilloma in frontal sinus in hospital. Six patients with inverted papilloma in frontal sinus treated between 1999 and 2006 were reported, with special emphasis on the clinical symptoms, surgical technique and prognosis. Among 6 patients with frontal sinus involvement, there were 5 males and 1 female, aged between 24 and 66 years. All 6 patients were managed with endoscopic resection and additional open approach (glabellar nasal keyhole approach). Follow-up ranged from 2 -8 years. Five patients treated with this protocol remained disease free, and 1 patient died of tumor recurrence and malignant degeneration 16 years after the first surgical management of sinonasal inverted papilloma. The appropriate management of inverted papilloma involving the frontal sinus is combined open/endoscopic approach. The tumor extended into the lateral, far superior, and anterior aspects of the frontal sinus is truly at the limits of current endoscopic instrumentation. In order to avoid recurrence, the tumor must be resected completely during the operation. Postoperative radiotherapy is not absolutely necessary. | 18,959,262 |
Palliative care nurse consultants in Melbourne: a snapshot of their clinical role. | The current role of the palliative care nurse consultant (PCNC) is as diverse as the organisations in which such nurses work. This study reports on Phase 2 of a larger study in Melbourne, Australia, which focused particularly on describing some of the clinical aspects of the work of the PCNC in the acute hospital setting. A cross-sectional survey was used to describe the selected clinical activities of the PCNC.A data collection sheet was developed to gather information about their work. 21 PCNCs participated in the study and data were collected for 282 patients within 12 acute hospitals in Melbourne. PCNCs recorded selected information about their clinical work for a two-week period. Descriptive analyses were carried out to calculate frequency distributions and mean scores. In 73% of referrals, the PCNC was the first contact the patient had with any palliative care health professional; patients with a malignant diagnosis constituted the main workload of the PCNC; the highest number of interventions was recorded for the symptom management/psychosocial care category; and the time from acute hospital admission to PCNC consult referral was 6.57 days. This study has demonstrated that the work of PCNCs is complex and diverse. This research forms the basis for further study into the role of the PCNC. | 18,959,284 |
Habitat-quality effects on metapopulation dynamics in greater white-toothed shrews, Crocidura russula. | The effects of patch size and isolation on metapopulation dynamics have received wide empirical support and theoretical formalization. By contrast, the effects of patch quality seem largely underinvestigated, partly due to technical difficulties in properly assessing quality. Here we combine habitat-quality modeling with four years of demographic monitoring in a metapopulation of greater white-toothed shrews (Crocidura russula) to investigate the role of patch quality on metapopulation processes. Together, local patch quality and connectivity significantly enhanced local population sizes and occupancy rates (R2 = 14% and 19%, respectively). Accounting for the quality of patches connected to the focal one and acting as potential sources improved slightly the model explanatory power for local population sizes, pointing to significant source-sink dynamics. Local habitat quality, in interaction with connectivity, also increased colonization rate (R2 = 28%), suggesting the ability of immigrants to target high-quality patches. Overall, patterns were best explained when assuming a mean dispersal distance of 800 m, a realistic value for the species under study. Our results thus provide evidence that patch quality, in interaction with connectivity, may affect major demographic processes. | 18,959,315 |
Impact of host community composition on Lyme disease risk. | The drivers of variable disease risk in complex multi-host disease systems have proved very difficult to identify. Here we test a model that explains the entomological risk of Lyme disease (LD) in terms of host community composition. The model was parameterized in a continuous forest tract at the Cary Institute of Ecosystem Studies (formerly the Institute of Ecosystem Studies) in New York State, U.S.A. We report the results of continuing longitudinal observations (10 years) at the Cary Institute, and of a shorter-term study conducted in forest fragments in LD endemic areas of Connecticut, New Jersey, and New York, USA. Model predictions were significantly correlated with the observed nymphal infection prevalence (NIP) in both studies, although the relationship was stronger in the longer-term Cary Institute study. Species richness was negatively, albeit weakly, correlated with NIP (logistic regression), and there was no relationship between the Shannon diversity index (H') and NIP. Although these results suggest that LD risk is in fact dependent on host diversity, the relationship relies explicitly on the identities and frequencies of host species such that conventional uses of the term biodiversity (i.e., richness, evenness, H') are less appropriate than are metrics that include species identity. This underscores the importance of constructing interaction webs for vertebrates and exploring the direct and indirect effects of anthropogenic stressors on host community composition. | 18,959,321 |
Dalteparin vs low-dose unfractionated heparin for prophylaxis against clinically evident venous thromboembolism in acute traumatic spinal cord injury: a retrospective cohort study. | When venous thromboembolism (VTE) includes deep-vein thrombosis (DVT) and pulmonary embolism (PE), patients with acute traumatic spinal cord injury (SCI) have the highest incidence of VTE among all hospitalized groups, with PE the third most common cause of death. Although low-molecular-weight heparin (LMWH) outperforms low-dose unfractionated heparin (LDUH) in other patient populations, the evidence in SCI remains less robust. To determine whether the efficacy for LMWH shown in previous SCI surveillance studies (eg, routine Doppler ultrasound) would translate into real-world effectiveness in which only clinically evident VTE is investigated (ie, after symptoms or signs present). A retrospective cohort study was conducted of 90 patients receiving LMWH dalteparin (5,000 U daily) or LDUH (5,000 U twice daily) for VTE prophylaxis after acute traumatic SCI. The incidence of radiographically confirmed VTE was primarily analyzed, and secondary outcomes included complications of bleeding and heparin-induced thrombocytopenia. There was no statistically significant association (p = 0.7054) between the incidence of VTE (7.78% overall) and the type of prophylaxis received (LDUH 3/47 vs dalteparin 4/43). There was no significant differences in complications, location of VTE, and incidence of fatal PE. Paraplegia (as opposed to tetraplegia) was the only risk factor identified for VTE. There continues to be an absence of definitive evidence for dalteparin (or other LMWH) over LDUH as the choice for VTE prophylaxis in patients with SCI. Novel approaches to VTE prophylaxis are urgently required for this population, whose risk of fatal PE has not decreased over the last 25 years. | 18,959,355 |
A trinuclear nickel(II) enediolate complex: synthesis, characterization, and O2 reactivity. | Using a new N(4)-donor chelate ligand having a mixture of hydrophobic phenyl and hydrogen-bond-donor appendages, a trinuclear nickel(II) complex of the doubly deprotonated form of 2-hydroxy-1,3-diphenylpropane-1,3-dione was isolated, characterized (X-ray crystallography, elemental analysis, UV-vis, (1)H NMR, FTIR, and magnetic moment measurement), and evaluated for O(2) reactivity. This complex, [(6-NA-6-Ph(2)TPANi)(2)(mu-PhC(O)C(O)C(O)Ph)(2)Ni](ClO(4))(2) (4), has two terminal pseudooctahedral Ni(II) centers supported by the tetradentate chelate ligand and a central square-planar Ni(II) ion ligated by oxygen atoms of two bridging enediolate ligands. In CH(3)CN, 4 exhibits a deep orange/brown color and lambda(max) = 463 nm (epsilon = 16 000 M(-1)cm(-1)). The room temperature magnetic moment of 4, determined by Evans method, is mu(eff) = 5.3(2) mu(B). This is consistent with the presence of two noninteracting high-spin Ni(II) centers, a diamagnetic central Ni(II) ion, and an overall quintet ground state. Exposure of a CH(3)CN solution of 4 to O(2) results in the rapid loss of the orange/brown color to give a green solution. The products identified from this reaction are [(kappa(3)-6-NA-6-Ph(2)TPA)Ni(O(2)Ph)(H(2)O)]ClO(4) (5), benzil [PhC(O)C(O)Ph], and CO. Identification of 5 was achieved via its independent synthesis and a comparison of its (1)H NMR and mass spectral features with those of the 6-NA-6-Ph(2)TPA-containing product generated upon reaction of 4 with O(2). The independently prepared sample of 5 was characterized by X-ray crystallography, elemental analysis, UV-vis, mass spectrometry, and FTIR. The O(2) reactivity of 4 has relevance to the active-site chemistry of Ni(II)-containing acireductone dioxygenase (Ni(II)ARD). | 18,959,363 |
Comparative behavior of britholites and monazite/brabantite solid solutions during leaching tests: a combined experimental and DFT approach. | In the field of the specific immobilization of actinides, several phosphate-based ceramics have already been proposed as suitable candidates. Among them, britholite and monazite/brabantite (now called monazite/cheralite) solid solutions have been considered as serious candidates on the basis of several properties of interest. Although both matrices appear almost similar from a chemical point of view, their chemical behavior during leaching tests appear to be strongly different with normalized dissolution rates of typically (2.1 +/- 0.2) g.m(-2).day(-1) for Th-britholites (10(-1)M HNO(3), theta = 25 degrees C, dynamic conditions) and (2.2 +/- 0.2) 10(-5) g.m(-2).day(-1) for Th-brabantites (10(-1)M HNO(3), theta = 90 degrees C, dynamic conditions). To understand such difference from a crystallographic point of view, comparative leaching tests have been performed using either high or low renewal of the leachate. The results obtained clearly revealed a lower chemical durability of An-britholites compared to that of (Ln, Ca, An)-monazite/brabantite solid solutions. As a confirmation of this point, density functional theory calculations clearly showed some great differences in the cohesive energy of calcium in both crystal structures, which can explain this strong difference in the chemical durability of both materials. | 18,959,370 |
Structures and magnetic properties of ferromagnetic coupling 2D Ln-M heterometallic coordination polymers (Ln = Ho, Er; M = Mn, Zn). | Four new heterometallic coordination polymers have been successfully synthesized, namely, {[Ho(2)(HCAM)(6)Mn(3)(H(2)O)(12)].17.5H(2)O}(n) (1), {[Er(2)(HCAM)(6)Mn(3)(H(2)O)(12)].17.5H(2)O}(n) (2), {[Ho(2)(HCAM)(6)Zn(3)(H(2)O)(12)].26H(2)O}(n) (3), and {[Er(2)(HCAM)(6)Zn(3)(H(2)O)(12)].26H(2)O}(n) (4) (H(3)CAM = chelidamic acid). X-ray crystallographic studies reveal that coordination polymers 1-4 are isostructural and crystallized in the rhombohedral crystal system, space group R3. These compounds comprise a 2D honeycomb-type framework. A 2D water sheet is first found in 3 and 4, which exhibits a novel topological motif. The magnetic results for 1-4 show that ferromagnetic interactions take place between the Ho(3+)/Er(3+) and Mn(2+) ions within 1 and 2. | 18,959,373 |
Octa- and nonanuclear nickel(II) polyoxometalate clusters: synthesis and electrochemical and magnetic characterizations. | Three high-nuclearity NiII-substituted polyoxometalate compounds functionalized by exogenous ligands have been synthesized and characterized. The octanuclear complexes in Na15[Na{(A-R-SiW9O34)Ni4(CH3COO)3(OH)3}2] . 4NaCl . 36H2O (1) and Na15[Na{(A-R-SiW9O34)Ni4(CH3COO)3(OH)2(N3)}2] . 32H2O (2) can be described as two {Ni4} subunits connected via a {Na(CH3COO)6} group, with the acetato ligands also ensuring in each subunit the connection between the paramagnetic centers. In 2, two azido groups replace two of the six mu-hydroxo ligands present in 1. The nonanuclear complex K7Na7[(A-R-SiW9O34)2Ni9(OH)6(H2O)6(CO3)3] . 42H2O (3) exhibits a double cubanestructure with two [(A-R-SiW9O34)Ni4(OH)3]5- subunits linked by three carbonato ligands. A ninth NiII center connected to one subunit via a carbonato ligand and a O=W group completes this asymmetric polyoxometalate.Electronic spectroscopy and electrochemical studies indicate that, while compounds 1-3 decompose in a pure aqueous medium, these complexes are very stable in a pH 6 acetate medium. The cyclic voltammetry pattern of each complex is constituted by a first eight-electron reduction wave followed by a second large-current intensity wave. The characteristics of the first waves of the complexes are clearly distinct from those obtained for their lacunary precursor [A-R-SiW9O34]10-, a feature that is due to the Ni centers in the complexes. Such observations of electroactive, stable, and highly nickel-rich polyoxometalates are not common. Measurements of the magnetic susceptibility revealed the occurrence of concomitant ferromagnetic and antiferromagnetic interactions in 1 and 3.For both of these compounds, the extension of the magnetic exchange has been determined by means of a spin Hamiltonian with three and four J constants, respectively. | 18,959,376 |
Phase diagrams and water activities of aqueous dicarboxylic acid systems of atmospheric importance. | We have studied liquid/solid phase diagrams and water activities of the dicarboxylic acid/water binary systems for maleic, dl-malic, glutaric, and succinc acids using differential scanning calorimetry, infrared (IR) spectroscopy of thin films, and conductivity analysis of saturated solutions. For each binary system we report the measurements of the ice melting envelope, the acid dissolution envelope, and the ice/acid eutectic temperature and composition. Water activities have been determined by using the freezing point depression of ice. Additionally, an irreversible solid/solid phase transition for maleic acid was observed in both DSC and IR studies likely due to the conversion of a meta-stable crystal form of maleic acid to its most stable crystal form. In general we find good agreement with literature values for temperature-dependent acid solubilities. | 18,959,391 |
Variations of diffusion coefficients of redox active molecules in room temperature ionic liquids upon electron transfer. | In ionic liquids, the diffusion coefficients of a redox couple vary considerably between the neutral and radical ion forms of the molecule. For a reduction, the inequality of the diffusion coefficients is characterized by the ratio gamma = D(red)/D(ox), where D(red) and D(ox) are the diffusion coefficients of the electrogenerated radical anion and of the corresponding neutral molecule, respectively. In this work, measurements of gamma have been performed by scanning electrochemical microscopy (SECM) in transient feedback mode, in three different room temperature ionic liquids (RTILs) sharing the same anion and with a series of nitro-derivative compounds taken as a test family. The smallest gamma ratios were determined in an imidazolium-based RTIL and with the charge of the radical anion localized on the nitro group. Conversely, gamma tends to unity when the radical anion is fully delocalized or when the nitro group is sterically protected by bulky substituents. The gamma ratios, standard potentials of the redox couple measured in RTILs, and those observed in a classical organic solvent were compared for the investigated family of compounds. The stabilization energies approximately follow the gamma ratios in a given RTIL but change considerably between ionic liquids with the nature of the cation. | 18,959,392 |
Model potential approaches for describing the interaction of excess electrons with water clusters: incorporation of long-range correlation effects. | In this work we focus on the binding of excess electrons to water clusters, a problem for which dispersion interactions, which originate from long-range correlation effects, are especially important. Two different model potential approaches, one using quantum Drude oscillators and the other using polarization potentials, are investigated for describing the long-range correlation effects between the weakly bound excess electron and the more tightly bound electrons of the monomers. We show that these two approaches are related in that the polarization potential models can be derived from the quantum Drude model approach by use of an adiabatic separation between the excess electron and the Drude oscillators. The model potential approaches are applied to clusters containing up to 45 water monomers. Where possible, comparison is made with the results of ab initio electronic structure calculations. Overall, the polarization potential approach is found to give electron binding energies in good agreement with those from the Drude model and ab initio calculations, with the greatest discrepancies being found for "cavity-bound" anion states. | 18,959,395 |
Absorption, uptake and tissue affinity of high-molecular-weight hyaluronan after oral administration in rats and dogs. | The purpose of this study was to determine the absorption, distribution and excretion of (99m)technetium-labeled, high-molecular-weight hyaluronan (((99m)Tc-HA) and (99m)technetium pertechnetate ((99m)Tc-P) after single dose, oral administration to Wistar rats and Beagle dogs. A pilot study utilized (99m)Tc-HA alone, and a second confirmatory study compared uptake of labeled (99m)Tc-HA with (99m)Tc-P. Urinary and fecal excretion after (99m)Tc-HA ingestion by rats showed 86.7-95.6% of radioactivity was recovered, almost all in feces. All tissues examined showed incorporation of radioactivity from (99m)Tc-HA starting at 15 min and persisting for 48 h, in a pattern significantly different from (99m)Tc-P. Whole-body scintigraphs and close-ups of the ventral chest region showed nonalimentary radioactivity from (99m)Tc-HA concentrated in joints, vertebrae and salivary glands four hours after administration. Autoradiography of skin, bone and joint tissue pieces after 24 h showed incorporation of radioactivity from (99m)Tc-HA, but not from (99m)Tc-P. Conversely, absorption, distribution and excretion of (99m)Tc was completely different from (99m)Tc-HA, showing an expected pattern of rapid absorption and excretion in urine, with accumulation in thyroid glands, stomach, kidney and bladder. This report presents the first evidence for uptake and distribution to connective tissues of orally administered, high-molecular-weight HA. | 18,959,406 |
Fractionation of antioxidants from autohydrolysis of barley husks. | The liquid phase from nonisothermal autohydrolysis of barley husks was extracted with ethyl acetate and redissolved in ethanol to yield a crude extract (denoted BHEAE), which was subjected to further processing to enhance the antioxidant activity. A fractionation method, carried out for characterization purposes, consisted of the extraction of BHEAE with organic solvents of increasing polarity and further fractionation in Sephadex LH-20. Among the tested solvents, ethyl acetate allowed the highest yield, phenolic content, and antioxidant activity. Upon elution with methanol, products with high DPPH radical scavenging capacity (IC50 = 0.22 g/L) were obtained. The major compounds in the isolate were benzoic and cinnamic acids. Adsorption-desorption in commercial polymeric resins was carried out as an alternative strategy for BHEAE refining. This method is more suited for possible scale-up and provided a concentrate with a Trolox equivalent antioxidant capacity of 9 mM, which was obtained at a yield of 18 g/kg of barley husks. | 18,959,408 |
Comparative proteomical analysis of zygotic embryo and endosperm from Coffea arabica seeds. | During coffee seed development, proteins are predominantly deposited in cotyledons and in the endosperm. Reserve proteins of the 11S family are the most abundant globulins in coffee seeds, acting as a nitrogen source during roasting and guaranteeing flavor and aroma. The aim of the present study was to compare the protein profiles of endosperm and zygotic embryos of coffee seeds. Proteins were extracted from whole seed as well as from embryo and endosperm, separately. Total proteins were analyzed by two-dimensional electrophoresis (2-DE) followed by identification by mass spectrometry (MS). The most abundant spots observed in the gels of coffee seeds were excised, digested with trypsin, and identified by MS as subunits of the 11S globulin. Spots with identical pI and molecular masses were also observed in the protein profiles of coffee endosperm and embryo, indicating that 11S protein is also highly expressed in those tissues. Peptide sequence coverage of about 20% of the entire 11S globulin was obtained. Three other proteins were identified in the embryo and endosperm 2-DE profiles as a Cupin superfamily protein, an allergenic protein (Pru ar 1), exclusive to the endosperm 2D map, and a hypothetical protein, observed only in the zygotic embryo profile. | 18,959,416 |
Influence of electron-beam irradiation on bioactive compounds in grapefruits ( Citrus paradisi Macf.). | Phytochemical levels in fruits and vegetables can be affected by several postharvest factors. In the present study, the effect of electron-beam (E-beam) irradiation was studied on grapefruit bioactive compounds. 'Rio Red' and 'Marsh White' grapefruits were irradiated with E-beam at 0, 1.0, 2.5, 5.0, and 10.0 kGy. Changes of various bioactive compounds, such as vitamin C, flavonoids, carotenoids, furocoumarins, and limonoids, were measured. The acidity decreased slightly with an increasing E-beam dose, whereas the total soluble solids were increased. Irradiation did not affect the vitamin C content at 1 kGy; however, doses beyond 1 kGy significantly reduced the vitamin C content. Lycopene and beta-carotene did not change significantly from the irradiation. Lycopene levels decreased as the E-beam dose increased, while the beta-carotene content slightly increased. Dihydroxybergamottin levels exhibited a decreasing trend, while the bergamottin content did not change. Naringin, a major flavonoid of grapefruit, showed a significant increase over the control at 10 kGy in both 'Rio Red' and 'Marsh White'. Nomilin continued to decrease with an increasing dose of E-beam irradiation, while limonin levels remained the same at all of the doses. Low-dose E-beam irradiation has very little effect on the bioactive compounds and offers a safe alternative to existing postharvest treatments for the disinfection and decontamination of grapefruits. | 18,959,418 |
Cu(I)-catalyzed hetero-Diels-Alder reaction between Danishefsky-type siloxy dienes and ketones. | A general catalytic method for the hetero-Diels-Alder reaction between Danishefsky-type siloxy dienes and ketones was developed. Optimum results were produced with a catalyst generated from CuOTf x (C6H6)1/2 and TBAT with Ph 3PO as the catalytic additive. This reaction was extended to an asymmetric variant, using a Cu(I)-Walphos catalyst. | 18,959,423 |
Highly selective alpha-acylvinyl anion additions to imines. | alpha-Hydroxypropargylsilanes undergo rearrangement to form reactive lithium allenolates. The resulting alpha-acylvinyl anion equivalents undergo highly selective additions to N-tert-butanesulfinyl imines generating beta-substituted aza-MBH-type products. High yields are achieved for a wide range of alpha-hydroxypropargylsilanes as well as for a diverse selection of imines. The reactions proceed with good to excellent diastereoselectivity and regioselectivity (8-20:1 major/ Sigma minor) favoring the Z-isomer of the alkene. | 18,959,427 |
Pure insulin nanoparticle agglomerates for pulmonary delivery. | Diabetes is a set of diseases characterized by defects in insulin utilization, either through autoimmune destruction of insulin-producing cells (Type I) or insulin resistance (Type II). Treatment options can include regular injections of insulin, which can be painful and inconvenient, often leading to low patient compliance. To overcome this problem, novel formulations of insulin are being investigated, such as inhaled aerosols. Sufficient deposition of powder in the peripheral lung to maximize systemic absorption requires precise control over particle size and density, with particles between 1 and 5 microm in aerodynamic diameter being within the respirable range. Insulin nanoparticles were produced by titrating insulin dissolved at low pH up to the pI of the native protein, and were then further processed into microparticles using solvent displacement. Particle size, crystallinity, dissolution properties, structural stability, and bulk powder density were characterized. We have demonstrated that pure drug insulin microparticles can be produced from nanosuspensions with minimal processing steps without excipients, and with suitable properties for deposition in the peripheral lung. | 18,959,432 |
Quantitative study of the structure of multilamellar giant liposomes as a container of protein synthesis reaction. | Liposomes are widely used as cell-sized compartments for encapsulation of biochemical reaction systems to construct model cell systems. However, liposomes are usually diverse in both size and structure, resulting in highly heterogeneous properties as microreactors. Here, we report the development of a strategy to investigate the internal structure of giant multilamellar vesicles (GMLVs) formed by the freeze-dried empty liposomes (FDEL) method as containers of an in vitro transcription/translation system. To evaluate the occurrence of the protein synthesis reaction in GMLVs, we designed a cascade reaction system in which a synthesized enzyme hydrolyzes the fluorescent substrate, and thus the space where the reaction takes place in liposomes becomes fluorescent. We found that only a part of the liposome was reactable and not the entire internal volume, i.e., the hydrolysis reaction took place in only a part of the fractured compartment volumes in GMLVs. Simultaneous measurement of the whole internal volume of the liposomes and the quantity of reaction product of more than 100 000 liposomes using a fluorescence-activated cell sorter (FACS) revealed that the distribution of reactable volume was proportional to the whole internal volume regardless of the liposome size, i.e., the relation between the quantity of whole and reactable volume in GMLV was found to be scale-free. This information would allow us to reduce the geometric parameters of GMLV for quantitative analysis of reaction kinetics in liposomes. The present measurement and analysis method will be an indispensable tool for exploring high-dimensional properties of a model cell system based on giant liposomes. | 18,959,434 |
Design, synthesis, and in vitro activity of novel drug delivery systems containing tuftsin derivatives and methotrexate. | During the past decade, biodegradable polymers or oligopeptides recognized by cell-surface receptors have been shown to increase drug specificity, lowering systemic drug toxicity in contrast to small-size fast-acting drugs. The goal of the present study was to develop anticancer bioconjugates based on chemotactic drug targeting (CDT). These constructs are composed of methotrexate (Mtx) attached to a tuftsin-like peptide carrier through an enzyme-labile pentapeptide spacer (GFLGC) and several copies of a chemotactic targeting moiety (H-TKPR, For-TKPR, H-TKPKG, and Ac-TKPKG). Carriers with targeting moieties in the branches were prepared by solid-phase synthesis using mixed Boc and Fmoc strategies. The drug molecule connected to an enzyme-labile spacer was attached to the branched oligopeptide in solution. In vitro chemotaxis, cellular uptake, and cytotoxicity assays were carried out on the MonoMac6 cell line. The most effective conjugates with H-TKPR or Ac-TKPKG targeting moieties in the branches, which have the most advantageous chemotactic properties, can be internalized rapidly, and these conjugates trigger higher toxic effect than the free drug (Mtx). The results suggest that our tuftsin-based drug delivery systems might be potential candidates for targeting cancer chemotherapy. | 18,959,436 |
Inhibition of cyclooxygenase 2 in mice increases production of g-csf and induces radioprotection. | Meloxicam, a selective inhibitor of cyclooxygenase 2, was tested to determine its ability to modulate hematopoiesis and to influence survival of mid-lethally gamma-irradiated mice. A single dose of meloxicam (20 mg/kg) administered to mice intraperitoneally 1 h before irradiation was shown to enhance serum levels of granulocyte colony-stimulating factor (G-CSF) during the first 24 h after irradiation, to elevate numbers of granulocytic precursor cells in bone marrow and granulocyte counts in peripheral blood on day 10 after irradiation, and to increase 30-day survival of these mice. The results provide new evidence for the protective ability of meloxicam administration to mice irradiated with mid-lethal doses and contribute to the understanding of the mechanisms of this meloxicam action by drawing attention to the possible role of increased endogenous G-CSF production. | 18,959,461 |
The effect of universal influenza immunization on mortality and health care use. | In 2000, Ontario, Canada, initiated a universal influenza immunization program (UIIP) to provide free influenza vaccines for the entire population aged 6 mo or older. Influenza immunization increased more rapidly in younger age groups in Ontario compared to other Canadian provinces, which all maintained targeted immunization programs. We evaluated the effect of Ontario's UIIP on influenza-associated mortality, hospitalizations, emergency department (ED) use, and visits to doctors' offices. Mortality and hospitalization data from 1997 to 2004 for all ten Canadian provinces were obtained from national datasets. Physician billing claims for visits to EDs and doctors' offices were obtained from provincial administrative datasets for four provinces with comprehensive data. Since outcomes coded as influenza are known to underestimate the true burden of influenza, we studied more broadly defined conditions. Hospitalizations, ED use, doctors' office visits for pneumonia and influenza, and all-cause mortality from 1997 to 2004 were modelled using Poisson regression, controlling for age, sex, province, influenza surveillance data, and temporal trends, and used to estimate the expected baseline outcome rates in the absence of influenza activity. The primary outcome was then defined as influenza-associated events, or the difference between the observed events and the expected baseline events. Changes in influenza-associated outcome rates before and after UIIP introduction in Ontario were compared to the corresponding changes in other provinces. After UIIP introduction, influenza-associated mortality decreased more in Ontario (relative rate [RR] = 0.26) than in other provinces (RR = 0.43) (ratio of RRs = 0.61, p = 0.002). Similar differences between Ontario and other provinces were observed for influenza-associated hospitalizations (RR = 0.25 versus 0.44, ratio of RRs = 0.58, p < 0.001), ED use (RR = 0.31 versus 0.69, ratio of RRs = 0.45, p < 0.001), and doctors' office visits (RR = 0.21 versus 0.52, ratio of RRs = 0.41, p < 0.001). Sensitivity analyses were carried out to assess consistency, specificity, and the presence of a dose-response relationship. Limitations of this study include the ecological study design, the nonspecific outcomes, difficulty in modeling baseline events, data quality and availability, and the inability to control for potentially important confounders. Compared to targeted programs in other provinces, introduction of universal vaccination in Ontario in 2000 was associated with relative reductions in influenza-associated mortality and health care use. The results of this large-scale natural experiment suggest that universal vaccination may be an effective public health measure for reducing the annual burden of influenza. | 18,959,473 |
An autonomous circadian clock in the inner mouse retina regulated by dopamine and GABA. | The influence of the mammalian retinal circadian clock on retinal physiology and function is widely recognized, yet the cellular elements and neural regulation of retinal circadian pacemaking remain unclear due to the challenge of long-term culture of adult mammalian retina and the lack of an ideal experimental measure of the retinal circadian clock. In the current study, we developed a protocol for long-term culture of intact mouse retinas, which allows retinal circadian rhythms to be monitored in real time as luminescence rhythms from a PERIOD2::LUCIFERASE (PER2::LUC) clock gene reporter. With this in vitro assay, we studied the characteristics and location within the retina of circadian PER2::LUC rhythms, the influence of major retinal neurotransmitters, and the resetting of the retinal circadian clock by light. Retinal PER2::LUC rhythms were routinely measured from whole-mount retinal explants for 10 d and for up to 30 d. Imaging of vertical retinal slices demonstrated that the rhythmic luminescence signals were concentrated in the inner nuclear layer. Interruption of cell communication via the major neurotransmitter systems of photoreceptors and ganglion cells (melatonin and glutamate) and the inner nuclear layer (dopamine, acetylcholine, GABA, glycine, and glutamate) did not disrupt generation of retinal circadian PER2::LUC rhythms, nor did interruption of intercellular communication through sodium-dependent action potentials or connexin 36 (cx36)-containing gap junctions, indicating that PER2::LUC rhythms generation in the inner nuclear layer is likely cell autonomous. However, dopamine, acting through D1 receptors, and GABA, acting through membrane hyperpolarization and casein kinase, set the phase and amplitude of retinal PER2::LUC rhythms, respectively. Light pulses reset the phase of the in vitro retinal oscillator and dopamine D1 receptor antagonists attenuated these phase shifts. Thus, dopamine and GABA act at the molecular level of PER proteins to play key roles in the organization of the retinal circadian clock. | 18,959,477 |
Opportunistic disease and mortality in patients coinfected with hepatitis B or C virus in the strategic management of antiretroviral therapy (SMART) study. | In the Strategic Management of Antiretroviral Therapy (SMART) study, the risk of opportunistic disease (OD) and/or death due to any cause was elevated in the drug conservation (i.e., interrupt antiretroviral therapy until the CD4(+) cell count is <250 cells/microL) group, compared with the viral suppression (continued use of antiretroviral therapy) group. We assessed whether participants with concurrent hepatitis had an increased risk of the end points evaluated in the SMART study. Participants were classified as being positive for hepatitis B virus (HBV) if they had positive hepatitis B surface antigen results for >6 months and positive for HCV if they tested HCV antibody positive. The rate and hazard ratio (HR) of OD and/or death and its 2 components were compared by hepatitis status and drug conservation versus the viral suppression group. Among 5472 participants enrolled from 8 January 2002 through 11 January 2006, 930 (17%) were HBV positive and/or HCV positive. The relative risk of non-OD death in participants randomized to the drug conservation group versus the viral suppression group was comparable regardless of hepatitis status (HR for coinfected and HIV-monoinfected participants, respectively, 1.9 [95% confidence interval {CI}, 1.0-3.9 and 1.8 [95% CI, 0.9-3.4]). The rate of OD or death was 3.9 events per 100 person-years in the coinfected group and 2.0 per 100 person-years in the HIV-monoinfected group. This excess risk was due to a higher risk of non-OD death among the coinfected participants (HR, 3.6; 95% CI, 2.3-5.6), whereas the risk of OD was comparable (HR, 1.1; 95% CI, 0.7-1.8). The 3 leading causes of non-OD death in coinfected participants were unknown cause, substance abuse, and non-acquired immunodeficiency disease cancer. Interruption of antiretroviral therapy is particularly unsafe in persons with hepatitis virus coinfection. Although HCV- and/or HBV-coinfected participants constituted 17% of participants in the SMART study, almost one-half of all non-OD deaths occurred in this population. Viral hepatitis was an unlikely cause of this excess risk. | 18,959,492 |
Eprinomectin 'pour-on' and the shedding of Haemonchus contortus eggs in experimentally infected goats. | The effect of eprinomectin on goats experimentally infected with the nematode Haemonchus contortus was investigated. Faecal analysis showed that a single dose of eprinomectin 'pour-on' delayed the onset of shedding of eggs for 10 to 17 days. | 18,959,535 |
Exploring the link between impulsivity and peer relations in 5- and 6-year-old children. | In recent years there has been an increased interest in the behavioural correlates of poor peer relations in childhood. It is now apparent that early poor peer relations are associated with negative future outcomes. The present study investigated whether behaviours that reflect impulsivity or require response inhibition are uniquely linked to children's peer relations. Five- and 6-year-old children's impulsivity was assessed using the teacher-rated impulsivity scale (TRIS), while the stop signal task and a modified version of Manly et al.'s opposite worlds task were employed as measures of response inhibition. In addition, peer relations measures were obtained for each child by asking their peers to indicate on a peer rating scale how much they would like to play with them. It was found that children's scores on the TRIS correlated significantly with peer relations measures (sociometric preference, peer acceptance and peer rejection) after controlling for gender, age and intelligence. Children rated by their teachers to be more impulsive had poorer peer relations. While there was a significant correlation between TRIS and stop-signal task performance, little relationship was found between either of the response inhibition measures and children's peer relations. The findings indicate that impulsivity is associated with children's poor relations with their peers and that this association is dependent upon the measure of impulsivity used. Whereas the more subjective teacher-ratings of impulsiveness did correlate with peer relations, the more objective behavioural measures of response inhibition, (thought to directly measure impulsivity), did not. The difference between these measures needs further investigation. While the data are correlational and causal direction can only be speculated, a practical implication of the finding of an association between impulsivity and peer acceptance is that adoption of strategies to minimize impulsive behaviour may improve the poor peer relations of children. | 18,959,575 |
Glycaemic control and diabetes care utilization in young adults with Type 1 diabetes. | To explore how glycaemic control in young adults is related to diabetes care utilization during the transition to adult diabetes care and if these variables differ between males and females. This is a retrospective, longitudinal design following patients' records from age 18-24 years. Adolescents (n = 104) connected to one paediatric outpatient clinic and referred to six different adult clinics were included. Data were collected regarding gender, age at diagnosis and transfer, yearly glycated haemoglobin (HbA(1c)) and body mass index, severe hypoglycaemia and diabetic ketoacidosis, retinopathy and diabetes care utilization. HbA(1c) decreased over time in females (P = 0.004) but not in males. Less than 10% had HbA(1c) in the recommended range during the study period. The decrease in severe hypoglycaemia and diabetic ketoacidosis was not significant. The prevalence of background retinopathy increased from 5 to 29% during the study period (P < 0.001). Mean transfer age was 19.8 years. The youths visited the paediatric clinic more often than the adult clinic (P < 0.001) and females visited adult care more often than males (P = 0.04). There was a steady decrease in the number of visits/year over time (P < 0. 001). Poor glycaemic control was associated with more visits for both males and females (P = 0.005) in adult care. As there was no gender difference in the relation between HbA(1c) and the number of visits in adult diabetes care, the higher frequency of visits in adult care for females cannot be solely explained by their glycaemic control. Gender differences regarding diabetes care utilization should be further explored. | 18,959,611 |
Risky individuals and the politics of genetic research into aggressiveness and violence. | New genetic technologies promise to generate valuable insights into the aetiology of several psychiatric conditions, as well as a wider range of human and animal behaviours. Advances in the neurosciences and the application of new brain imaging techniques offer a way of integrating DNA analysis with studies that are looking at other biological markers of behaviour. While candidate 'genes for' certain conditions, including schizophrenia and bipolar disorders, are said to be 'un-discovered' at a faster rate than they are discovered, many studies are being conducted on personality traits such as aggressiveness and anti-social traits. The clinical applicability and implications of these studies are often discussed within the scientific community. However, little attention has so far been paid to their possible policy implications in relation to criminality management and to Criminal Law itself. Similarly, the related ethical issues arising in the field of crime control, and the tensions between enhancing security for society and protecting civil liberties, are currently under-explored. This paper investigates these ethical issues by focusing on the views of those professionals - including judges, lawyers, probation officers and social workers - who work with individuals 'deemed at risk' of violent and aggressive behaviours. It also discusses and problematizes mainstream rhetoric and arguments around the notion of 'risky individuals'. | 18,959,733 |
Energetic and metabolic transient response of Saccharomyces cerevisiae to benzoic acid. | Saccharomyces cerevisiae is known to be able to adapt to the presence of the commonly used food preservative benzoic acid with a large energy expenditure. Some mechanisms for the adaptation process have been suggested, but its quantitative energetic and metabolic aspects have rarely been discussed. This study discusses use of the stimulus response approach to quantitatively study the energetic and metabolic aspects of the transient adaptation of S. cerevisiae to a shift in benzoic acid concentration, from 0 to 0.8 mM. The information obtained also serves as the basis for further utilization of benzoic acid as a tool for targeted perturbation of the energy system, which is important in studying the kinetics and regulation of central carbon metabolism in S. cerevisiae. Using this experimental set-up, we found significant fast-transient (< 3000 s) increases in O(2) consumption and CO(2) production rates, of approximately 50%, which reflect a high energy requirement for the adaptation process. We also found that with a longer exposure time to benzoic acid, S. cerevisiae decreases the cell membrane permeability for this weak acid by a factor of 10 and decreases the cell size to approximately 80% of the initial value. The intracellular metabolite profile in the new steady-state indicates increases in the glycolytic and tricarboxylic acid cycle fluxes, which are in agreement with the observed increases in specific glucose and O(2) uptake rates. | 18,959,741 |
Soluble recombinant CD69 receptors optimized to have an exceptional physical and chemical stability display prolonged circulation and remain intact in the blood of mice. | We investigated the soluble forms of the earliest activation antigen of human leukocyte CD69. This receptor is expressed at the cell surface as a type II homodimeric membrane protein. However, the elements necessary to prepare the soluble recombinant CD69 suitable for structural studies are a matter of controversy. We describe the physical, biochemical and in vivo characteristics of a highly stable soluble form of CD69 obtained by bacterial expression of an appropriate extracellular segment of this protein. Our construct has been derived from one used for CD69 crystallization by further optimization with regard to protein stability, solubility and easy crystallization under conditions promoting ligand binding. The resulting protein is stable at acidic pH and at temperatures of up to 65 degrees C, as revealed by long-term stability tests and thermal denaturation experiments. Protein NMR and crystallography confirmed the expected protein fold, and revealed additional details of the protein characteristics in solution. The soluble CD69 refolded in a form of noncovalent dimers, as revealed by gel filtration, sedimentation velocity measurements, NMR and dynamic light scattering. The soluble CD69 proved to be remarkably stable in vivo when injected into the bloodstream of experimental mice. More than 70% of the most stable CD69 proteins is preserved intact in the blood 24 h after injection, whereas the less stable CD69 variants are rapidly taken up by the liver. | 18,959,746 |
Microarray analyses of hypoxia-regulated genes in an aryl hydrocarbon receptor nuclear translocator (Arnt)-dependent manner. | We investigated hypoxia-inducible factor (HIF)-dependent changes in the expression of 5592 genes in response to hypoxia (0.1% O(2), 16 h) by performing cDNA microarray analyses of mouse hepa1c1c7 and BpRc1 cells. BpRc1 cells are a hepa1c1c7 variant defective in HIF-beta/aryl hydrocarbon receptor nuclear translocator (Arnt), and are therefore unable to induce HIF target genes in response to hypoxia. By comparing hepa1c1c7 cells with BpRc1 cells, we were able to investigate hypoxia-regulated gene expression as well as the role played by HIF in regulating the hypoxic-dependent response of gene expression. This study identified 50 hypoxia-induced genes and 36 hypoxia-repressed genes. Quantitative PCR analysis of nine genes confirmed our ability to accurately analyze changes in hypoxia-induced gene expression by microarray analysis. By comparing quantitative PCR analyses of these nine genes in BpRc1 and hepa1c1c7 cells, we determined that eight of the nine hypoxia-induced genes are Arnt dependent. Additional quantitative PCR analyses of eight hypoxia-repressed genes confirmed, with a 50% probability, that microarray analysis was able to predict hypoxia-repressed gene expression. Only two of the four confirmed genes were found to be repressed in an Arnt-dependent manner. Collectively, six of these 13 genes (46.2% probability) showed a pattern of expression consistent with the microarray analysis with regard to Arnt dependence. Finally, we investigated the HIF-1alpha dependence of these 13 genes by quantitative PCR analysis in HIF-1alpha knockdown 3T3-L1 cells. These analyses identified novel hypoxia-regulated genes and confirmed the role of Arnt and HIF-1alpha in regulating their expression. These results identify additional HIF target genes and provide a more complete understanding of hypoxia signaling. | 18,959,748 |
Hexameric ring structure of a thermophilic archaeon NADH oxidase that produces predominantly H2O. | An NADH oxidase (NOX) was cloned from the genome of Thermococcus profundus (NOXtp) by genome walking, and the encoded protein was purified to homogeneity after expression in Escherichia coli. Subsequent analyses showed that it is an FAD-containing protein with a subunit molecular mass of 49 kDa that exists as a hexamer with a native molecular mass of 300 kDa. A ring-shaped hexameric form was revealed by electron microscopic and image processing analyses. NOXtp catalyzed the oxidization of NADH and NADPH and predominantly converted O(2) to H(2)O, but not to H(2)O(2), as in the case of most other NOX enzymes. To our knowledge, this is the first example of a NOX that can produce H(2)O predominantly in a thermophilic organism. As an enzyme with two cysteine residues, NOXtp contains a cysteinyl redox center at Cys45 in addition to FAD. Mutant analysis suggests that Cys45 in NOXtp plays a key role in the four-electron reduction of O(2) to H(2)O, but not in the two-electron reduction of O(2) to H(2)O(2). | 18,959,761 |
Semi-nested PCR analysis of unknown tags on serial analysis of gene expression. | Serial analysis of gene expression (SAGE) is a powerful technique for studying gene expression at the genome level. However, short SAGE tags limit the further study of related data. In this study, in order to identify a gene, we developed a semi-nested PCR-based method called the two-step analysis of unknown SAGE tags (TSAT-PCR) to generate longer 3'-end cDNA fragments from unknown SAGE tags. In the procedure, a modified lock-docking oligo(dT) with two degenerate nucleotide positions at the 3'-end was used as a reverse primer to synthesize cDNAs. Afterwards, the full-length cDNAs were amplified by PCR based on 5'-RACE and 3'-RACE. The amplified cDNAs were then used for the subsequent two-step PCR of the TSAT-PCR process. The first-step PCR was carried out at an appropriately low annealing temperature; a SAGE tag-specific primer was used as the sense primer, and an 18 bp sequence (universal primer I) located at the 5'-reverse primer end was used as the antisense primer. After 15-20 PCR cycles, the 3'-end cDNA fragments containing the tag could be enriched, and the PCR products could be used as templates for the second-step PCR to obtain the specific products. The second-step PCR was performed with a SAGE tag-specific primer and a 22-bp sequence (universal primer II) upstream of universal primer I at the 5'-reverse primer with a high annealing temperature. With our innovative TSAT-PCR method, we could easily obtain specific PCR products covering SAGE from those transcripts, especially low-abundance transcripts. It can be used as a method to identify genes expressed in different cell types. | 18,959,766 |
Integrating chromosomal aberrations and gene expression profiles to dissect rectal tumorigenesis. | Accurate staging of rectal tumors is essential for making the correct treatment choice. In a previous study, we found that loss of 17p, 18q and gain of 8q, 13q and 20q could distinguish adenoma from carcinoma tissue and that gain of 1q was related to lymph node metastasis. In order to find markers for tumor staging, we searched for candidate genes on these specific chromosomes. We performed gene expression microarray analysis on 79 rectal tumors and integrated these data with genomic data from the same sample series. We performed supervised analysis to find candidate genes on affected chromosomes and validated the results with qRT-PCR and immunohistochemistry. Integration of gene expression and chromosomal instability data revealed similarity between these two data types. Supervised analysis identified up-regulation of EFNA1 in cases with 1q gain, and EFNA1 expression was correlated with the expression of a target gene (VEGF). The BOP1 gene, involved in ribosome biogenesis and related to chromosomal instability, was over-expressed in cases with 8q gain. SMAD2 was the most down-regulated gene on 18q, and on 20q, STMN3 and TGIF2 were highly up-regulated. Immunohistochemistry for SMAD4 correlated with SMAD2 gene expression and 18q loss. On basis of integrative analysis this study identified one well known CRC gene (SMAD2) and several other genes (EFNA1, BOP1, TGIF2 and STMN3) that possibly could be used for rectal cancer characterization. | 18,959,792 |
Blunt injury to the inferior gluteal artery: case report of a rare "near miss" event. | Traumatic injuries of the inferior gluteal artery are rare, the majority of which are aneurysms due to sharp or blunt trauma. We report the rare case of a "near miss" event of a patient with an acute hemorrhagic mass in the right buttock caused by blunt trauma to the inferior gluteal artery without "hard" clinical signs of vascular injury. Despite the unusual presentation, diffuse injury of the inferior gluteal artery branches was diagnosed by ultrasonography and angiography. This article highlights the importance of considering an arterial injury following blunt trauma to the buttock with subsequent pain and swelling. Appreciation of this rare injury pattern is necessary in order to facilitate rapid diagnosis and appropriate treatment. | 18,959,806 |
A new method for the study of essential fatty acid requirements in fish larvae. | This study describes a methodology with potential application in the estimation of essential fatty acid (EFA) requirements of fish larvae. Senegalese sole (Solea senegalensis) larvae were fed, from 16 days after hatching (DAH), on Artemia enriched with different oils, inducing graded dietary concentrations of DHA: (1) soyabean oil, containing no measurable amounts of DHA (NDHA); (2) fish oil, inducing a medium DHA level (MDHA, 3 g DHA/100 g fatty acids); and (3) a mixture of Easy DHA Selco and Microfeed, resulting in high DHA content (HDHA, 8 g/100 g). At 28 DAH a metabolic trial was conducted where larvae were tube fed [1-(14) C]DHA, in order to determine its absorption, retention in the gut and body tissues, as well as its oxidation. At 23 DAH the HDHA treatment induced a significantly higher larval growth, while at 32 DAH significant differences were only found between the NDHA and HDHA treatments. The absorption of tube-fed [1-(14) C]DHA was extremely high (94-95 %) and independent of feeding regime. However, in larvae fed NDHA Artemia, a significantly higher amount of label was retained in the gut compartment and a concurrently lower retention was measured in the body. A significantly higher proportion of the absorbed DHA label was oxidized in larvae fed HDHA, compared to NDHA. Based on these results, we suggest that increasing dietary supply of DHA above the larval requirement level results in its increased oxidation for energy purposes and we propose potential applications of the tube feeding methodology using radiolabelled EFA in conjunction with dose-response studies. | 18,959,810 |
Leptin and mechanisms of endothelial dysfunction and cardiovascular disease. | Leptin, a product of the obesity gene, is a molecule that has received much attention since its cloning in 1994. Initially, most work centered around the effects of leptin on satiety and energy balance. However, in recent years there has been an intense focus on leptin as it relates to the cardiovascular system. Plasma leptin concentration is markedly elevated in obesity and the metabolic syndrome, both of which are associated with increased incidence of cardiovascular pathologies. In many studies, hyperleptinemia has been linked to endothelial dysfunction (a known precursor to atherosclerotic cardiovascular disease) and activation of the sympathetic nervous system. Additionally, recent evidence suggests that leptin released from perivascular adipose tissue may also have deleterious effects on the underlying vasculature, including the coronary circulation. This report reviews pertinent literature on leptin-mediated endothelial dysfunction, leptin-mediated sympathetic activation, and leptin as a significant perivascular adipose-derived factor. | 18,959,828 |
Determination of boron in nickel-base alloys by the dianthrimide method. | The dianthrimide method for the determination of boron in iron and low-alloy steels may be applied to nickel-base materials. The sample is dissolved, without any loss of boron, by hydrochloric and sulphuric acids and the resulting boric acid determined spectrophotometrically with dianthrimide. Background corrections are necessary to compensate for the absorbance from ions such as nickel and iron. | 18,959,846 |
Intermittent Escherichia coli O157:H7 colonisation at the terminal rectum mucosa of conventionally-reared lambs. | In cattle, the lymphoid rich regions of the rectal-anal mucosa at the terminal rectum are the preferred site for Escherichia coli O157:H7 colonisation. All cattle infected by rectal swab administration demonstrate long-term E. coli O157:H7 colonisation, whereas orally challenged cattle do not demonstrate long-term E. coli O157:H7 colonisation in all animals. Oral, but not rectal challenge of sheep with E. coli O157:H7 has been reported, but an exact site for colonisation in sheep is unknown. To determine if E. coli O157:H7 can effectively colonise the ovine terminal rectum, in vitro organ culture (IVOC) was initiated. Albeit sparsely, large, densely packed E. coli O157:H7 micro-colonies were observed on the mucosa of ovine and control bovine terminal rectum explants. After necropsy of orally inoculated lambs, bacterial enumeration of the proximal and distal gastrointestinal tract did suggest a preference for E. coli O157:H7 colonisation at the ovine terminal rectum, albeit for both lymphoid rich and non-lymphoid sites. As reported for cattle, rectal inoculation studies were then conducted to determine if all lambs would demonstrate persistent colonisation at the terminal rectum. After necropsy of E. coli O157:H7 rectally inoculated lambs, most animals were not colonised at gastrointestinal sites proximal to the rectum, however, large densely packed micro-colonies of E. coli O157:H7 were observed on the ovine terminal rectum mucosa. Nevertheless, at the end point of the study (day 14), only one lamb had E. coli O157:H7 micro-colonies associated with the terminal rectum mucosa. A comparison of E. coli O157:H7 shedding yielded a similar pattern of persistence between rectally and orally inoculated lambs. The inability of E. coli O157:H7 to effectively colonise the terminal rectum mucosa of all rectally inoculated sheep in the long term, suggests that E. coli O157:H7 may colonise this site, but less effectively than reported previously for cattle. | 18,959,839 |
Non-destructive neutron-activation analysis for determining the chlorine content of paper-pulp. | Non-destructive neutron-activation analysis is used for determining chlorine in paper-pulp. Numerical data have been obtained for bleached and unbleached paper-pulps of different types and origins. The sensitivity of this method is 100 ppm for an irradiation time of 30 min and a neutron flux of 6 x 10(10) neutrons.cm(-2).sec(-1) and 10 ppm for an irradiation time of 1 min and a neutron flux of 2 x 10(12) neutrons.cm(-2).sec(-1). In both cases the amount of chlorine that can be determined depends on the presence of the interfering elements manganese and sodium in the paper-pulp. The time required for a complete analysis, after irradiation, is 5 min. | 18,959,861 |
Wollack titration of thiosulphate. | The Wollack titration for the determination of thiosulphate has been reinvestigated. Various modifications are proposed and the conditions necessary for satisfactory results are discussed. | 18,959,883 |
Dithizonates of gold and palladium. | Contrary to some previous reports, it has been found that gold reacts with dithizone in the ratio 1:1 forming a red-brown complex, and in the ratio 2:1 forming a yellow complex, both extractable into chloroform. The proportion of these two complexes in the organic extract depends critically on several factors. Therefore, the use of dithizone as a spectrophotometric reagent and especially as an extractive titrant for gold cannot be recommended. Previous reports on the composition and colour of the dithizonates of palladium are confirmed, except that PdDz is soluble in carbon tetrachloride and in chloroform. | 18,959,884 |
Fluorometric titration of calcium, magnesium and iron using calcein blue as indicator. | Calcium, magnesium and iron can be determined by successive fluorometric titration without separation. Calcium is titrated directly with EGTA at a pH 13; magnesium is determined by a substitution reaction with copper-EDTA complex at a pH of about 11 ; and iron is titrated directly with EDTA in the presence of hydrogen peroxide at a pH of 10.5, after destroying its triethanolamine complex. Calcein Blue serves as an indicator in all of the titrations and as a fluorescent standard. The end-points are sharp and the accuracy is good for various proportions of the metal ions. The method is simple, reproducible and inexpensive. Standard solutions of ions, limestone, cement and serum samples have been analysed by the proposed method. | 18,959,889 |
Determination of gold by X-ray fluorescence methods. | X-ray fluorescence methods for the determination of gold in silver beads and in hydrochloric acid solutions are described. These techniques may be applied to silver containing 0.2-5 % of gold and to solutions containing 0.004-0.1% of gold. Platinum, palladium, rhodium and indium do not interfere. | 18,959,913 |
Spectrofluorimetric determination of submicrogram amounts of aluminium using salicylidene-o-aminophenol. | Salicylidene-o-aminophenol provides a sensitive spectrofluorimetric reagent for the determination of aluminium down to 27 ng (or 2.7 x 10(-4) ppm in the final solution). The most suitable conditions of pH (5.6), reagent concentration and development time (>20 min) have been established. Extraction with sodium diethyldithiocarbamate into ethyl acetate at the pH of the determination renders the method highly selective; out of 46 foreign cations examined only chromium(III), scandium and thorium interfere. Anions which form complexes with aluminium, such as citrate, tartrate and fluoride, also cause interference, but none of the common anions interferes. A 1:1 stoichiometry of the complex has been established and some conclusions have been drawn concerning its nature. | 18,959,922 |
Determination of free acid in antimony(III) and bismuth(III) solutions. | A method for the determination of free acid in antimony(III) and bismuth(III) solutions is given. A solution of the disodium salt of EDTA, 2-3 % in excess of the stoichiometric amount, is added to the metal salt solution and titrated with sodium hydroxide solution potentiometrically or visually using a mixed indicator. The error in the method is less than 0.5 %. | 18,959,924 |
Quantitative infrared analysis of 2,4-tolylene diamine and 2,4-tolylene diurea mixtures. | A rapid method is described for the simultaneous determination of 2,4-tolylene diamine and 2,4-tolylene diurea by infrared spectroscopy. The method is satisfactory for the diurea determination but gives rather large errors in the diamine determination. | 18,959,936 |
Determination of cadmium by atomic-fluorescence and atomic-absorption spectrophotometry. | The adaptation of a conventional atomic-absorption/flameemission spectrophotometer to the measurement of atomic-fluorescence in an air-acetylene flame is described. The determination of cadmium on the same instrument by both atomic-fluorescence and absorption shows that, even with a rather simple and inefficient means of exciting and measuring fluorescence, results can be obtained which indicate that the fluorescence technique is considerably more sensitive than atomic-absorbance and is equally free from inter-element interference. | 18,959,939 |
Chromotropic acid azo dyes of the pyridine series Spectrophotometric determination of nickel and cobalt in the presence of many ions and their simultaneous determination. | Pyridyl-2-azo-chromotropic acid (disodium salt) is proposed as a new reagent for the determination of nickel and cobalt in the presence of many ions and for their simultaneous determination in the absence of cyanide and EDTA. The wavelengths of maximum absorption for the nickel and cobalt complexes are 570 and 640 mmu respectively. Beer's law is obeyed by the complex systems from 0.125-0.8 ppm of nickel and 0.16-1.2 ppm of cobalt. The optimum concentration ranges are 0.25-0.8 ppm for nickel and 0.16-1.2 ppm for cobalt and the relative error is 2.7 %. The molar absorptivities for the complexes of nickel and cobalt are 40,720 and 33,600, while the dissociation constants at pH 7.5 and 22 degrees are of the order of 10(-12) and 10(-13), respectively. The metal to reagent ratio is 1:3. | 18,959,942 |
Determination of indium in standard rocks by neutron activation analysis. | A rapid neutron activation method for the determination of indium in rocks, based on 54 min (116m)In, is described. The method has been applied to a series of geochemical standards including granite G-1 and diabase W-1. The precision is better than +/- 5% for samples containing more than 5 x 10(-10)g indium. Good agreement with previously published values for G-1 and W-1 has been obtained. | 18,959,988 |
A new automatic recording titrator and its applications. | A new type of automatic recording titrator has been developed. The titrant is added intermittently and the titration curve is recorded stepwise, potential changes being registered in the intervals between deliveries of titrant. The increments of titrant and the intervals can be pre-set, but give the best results if controlled automatically during the titration. The end-point and the volume of titrant consumed are read from the recorded titration curve. | 18,960,001 |
Spectral characterisation of nitroarenes and polycyclic aldehydes, ketones, quinones and amines. | Three methods are introduced for the post-chromatographic spectral characterisation of carbonyl and nitro compounds. Most often, elution from the chromatogram is necessary, but sometimes fluorescence spectra can be obtained directly from the chromatograra. The usefulness and sensitivity of the methods have been demonstrated for a variety of nitroarenes and polycyclic aldehydes, ketones, quinones and amines. | 18,960,013 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.