title
stringlengths 0
1.13k
| abstract
stringlengths 1
15.7k
| PMID
int64 22
36.5M
|
|---|---|---|
Advances in magnetic resonance (2008).
|
Current advances in magnetic resonance, as a diagnostic modality, are discussed in the context of publications from Investigative Radiology during 2007 and 2008. The articles relating to this topic, published during the past 2 years, are reviewed by anatomic region. The discussion concludes with a consideration of magnetic resonance contrast media, focusing on studies published in the journal, and examining in particular the potential impact of nephrogenic systemic fibrosis.
| 19,002,061
|
Functional performance following an ice bag application to the hamstrings.
|
This study examined the immediate and short-term (20 minute) effects of 3- and 10-minute ice bag applications to the hamstrings on functional performance as measured by the cocontraction test, shuttle run, and single-leg vertical jump. Forty-two (25 women, 17 men) recreational or collegiate athletes who were free of injury in the lower extremity 6 months before testing and who did not suffer from allergy to cryotherapy were included. Time to completion was measured in seconds for the cocontraction and the shuttle run test. Single-leg vertical jump was measured on the Vertec (Sports Imports, Columbus, Ohio) in centimeters. The 10-minute ice bag application reduced immediate post-application vertical jump performance and increased immediate post and 20-minute post shuttle run time (p <or= 0.05). A decrease in cocontraction time was observed at 20 minutes post compared with preapplication during the control condition in which no ice bag was applied. Power and functional performance are affected by short-term cryotherapy application. Power and functional performance was impaired immediately and 20 minutes after 10-minute ice bag application to the hamstrings, whereas a shorter duration of ice application had no effect on these tasks.
| 19,002,074
|
[The role of lactoferrin in the iron metabolism. Part I. Effect of lactofferin on intake, transport and iron storage].
|
Iron belongs to the most widely distributed elements and is essential for the metabolism of almost all organisms. It is required for enzymatic reactions, in particular of those involving electron transport. It also participates in the transport and storage of oxygen in tissues. Iron is present in hem-containing proteins (hemoproteins) such as: hemoglobin, myoglobin, cytochromes,cytochrome oxidases, catalases and peroxidases. It is also a constituent of proteins which do not contain hem molecule: flavoproteins (succinate and NADH dehydrogenase) and of mitochondrial aconitase. In addition, iron takes part in many metabolic processes, among others in synthesis and catabolism of some hormones, synthesis of high-energy compounds and collagen, detoxification processes and immune reactions. It also participates in formation of reactive oxygen species which may exhibit both beneficial and harmful effects. Iron occurs in aqueous solutions as ferric (Fe+++) and ferrous (Fe++) ion. Although Fe+++ is hardly soluble, the organisms evolved mechanisms allowing to acquire and utilize that element irrespectively of its valency. The iron metabolism encompasses: intake, transport, participation in metabolism and storage. The iron metabolism undergoes in a closed cycle; in the physiological state only small amount of this metal is absorbed in the alimentary duct and disposed from the organism. A number of proteins is involved in iron metabolism including: ferritin, transferrin,transferrin receptor, divalent metal transporter (DMT1), cytochrome b, ferroportin, hephaestin, hepcidin and lactoferrin (LF). A beneficial effect of LF on iron acquisition in the gut is best documented.That process involves a receptor-mediated absorption of iron-bound LF through intestinal epithelial cells. The role of LF in transfer of iron from maternal milk may be of utmost importance. Many observations indicate also that LF participates in the process of iron storage,predominantly in the liver. Contradictory data exist, however, regarding the role of LF in iron transport to other cell types and organs.
| 19,002,083
|
Effects of recombinant human activated protein C on the fibrinolytic system of patients undergoing conventional or tight glycemic control.
|
Recombinant human activated protein C (rh-APC) and tight glycemic control (TGC) have been shown to reduce mortality in septic patients. Both interventions can reduce the plasma concentration and/or activity of the most powerful suppressor of fibrinolysis, plasminogen activator inhibitor-1 (PAI-1). Our aim was to evaluate the effects on the fibrinolytic system after the administration of rh-APC in septic patients undergoing conventional or TGC. Posthoc analysis of data was collected from 90 patients with severe sepsis/septic shock, randomized to either conventional or TGC groups. Independent of these treatments, patients with at least two organ dysfunctions simultaneously received rh-APC. Plasma levels of multiple biochemical markers for fibrinolysis, coagulation, and inflammation were determined every day for the 1st week and then on study days 9, 11, 13, 18, 23, and 28. Clinical data and sepsis-related organ failure assessment (SOFA) scores were also recorded. Patients who had received rh-APC exhibited significantly more impairments in fibrinolysis at baseline (PAI-1 activity 49.76 [24.61-71.82] vs 21.92 [6.47-55-83] IU/mL, P=0.03). The reductions in plasma PAI-1 activity over time associated with rh-APC treatment were different according to whether the treatment was administered to patients undergoing conventional or TGC (P=0.01). However, the most prominent reductions were in patients undergoing conventional glycemic control. Significant interactions between the two study interventions were also found for PAI-1 concentration (P<0.001), C-reactive protein (P=0.02), and interleukin-6 levels (P<0.001). Both rh-APC and TGC appear to improve fibrinolysis in septic patients. The reduction in the impairment of fibrinolysis associated with rh-APC treatment seems greater in patients undergoing conventional glycemic control than in those undergoing TGC.
| 19,002,087
|
Administration of type A botulinum toxin after total hip replacement.
|
Pain after hip replacement is one of the most common problems during rehabilitation and is often the main obstacle in rehabilitation, even though it can often be controlled by localized cryotherapy and/or administration of analgesics. However, patients with positive anamnesis for hip arthritis and long-lasting pain may report persistence of symptoms for months after surgical intervention; often, in these patients, contractures and muscle retraction in the pelvic region are observed. The present study reports the case of a female patient who suffered from complications after total hip replacement (THR) for osteoarthritis. Due to severe pain in the gluteal region not responding to standard treatments the patient was unable to stand in an upright position or walk, so she was forced to stop the rehabilitation program. Treatment by injection of botulinum toxin type A (BTX-A) in the gluteus maximus muscle brought about the complete resolution of pain and functional recovery. The follow-up visits, carried out after 6 and 16 months, confirmed the complete healing of the patient. BTX-A has been shown to be effective in the treatment of painful localized contractures even in the absence of neurological lesions. Therefore, BTX-A could be a feasible option to treat painful localized contractures that do not respond to standard treatments. Further investigations are suggested to better identify appropriate dosages and the best inoculation schedule.
| 19,002,096
|
Etomidate reduces glutamate uptake in rat cultured glial cells: involvement of PKA.
|
Glutamate is the main excitatory neurotransmitter in the vertebrate CNS. Removal of the transmitter from the synaptic cleft by glial and neuronal glutamate transporters (GLTs) has an important function in terminating glutamatergic neurotransmission and neurological disorders. Five distinct excitatory amino-acid transporters have been characterized, among which the glial transporters excitatory amino-acid transporter 1 (EAAT1) (glutamate aspartate transporter) and EAAT2 (GLT1) are most important for the removal of extracellular glutamate. The purpose of this study was to describe the effect of the commonly used anaesthetic etomidate on glutamate uptake in cultures of glial cells. The activity of the transporters was determined electrophysiologically using the whole cell configuration of the patch-clamp recording technique. Glutamate uptake was suppressed by etomidate (3-100 microM) in a time- and concentration-dependent manner with a half-maximum effect occurring at 2.4+/-0.6 microM. Maximum inhibition was approximately 50% with respect to the control. Etomidate led to a significant decrease of V(max) whereas the K(m) of the transporter was unaffected. In all cases, suppression of glutamate uptake was reversible within a few minutes upon washout. Furthermore, both GF 109203X, a nonselective inhibitor of PKs, and H89, a selective blocker of PKA, completely abolished the inhibitory effect of etomidate. Inhibition of glutamate uptake by etomidate at clinically relevant concentrations may affect glutamatergic neurotransmission by increasing the glutamate concentration in the synaptic cleft and may compromise patients suffering from acute or chronic neurological disorders such as CNS trauma or epilepsy.
| 19,002,104
|
Epigenetic regulation of centromeric chromatin: old dogs, new tricks?
|
The assembly of just a single kinetochore at the centromere of each sister chromatid is essential for accurate chromosome segregation during cell division. Surprisingly, despite their vital function, centromeres show considerable plasticity with respect to their chromosomal locations and activity. The establishment and maintenance of centromeric chromatin, and therefore the location of kinetochores, is epigenetically regulated. The histone H3 variant CENP-A is the key determinant of centromere identity and kinetochore assembly. Recent studies have identified many factors that affect CENP-A localization, but their precise roles in this process are unknown. We build on these advances and on new information about the timing of CENP-A assembly during the cell cycle to propose new models for how centromeric chromatin is established and propagated.
| 19,002,142
|
Signaling cross-talk between TGF-beta/BMP and other pathways.
|
Transforming growth factor-beta (TGF-beta)/bone morphogenic protein (BMP) signaling is involved in the vast majority of cellular processes and is fundamentally important during the entire life of all metazoans. Deregulation of TGF-beta/BMP activity almost invariably leads to developmental defects and/or diseases, including cancer. The proper functioning of the TGF-beta/BMP pathway depends on its constitutive and extensive communication with other signaling pathways, leading to synergistic or antagonistic effects and eventually desirable biological outcomes. The nature of such signaling cross-talk is overwhelmingly complex and highly context-dependent. Here we review the different modes of cross-talk between TGF-beta/BMP and the signaling pathways of Mitogen-activated protein kinase, phosphatidylinositol-3 kinase/Akt, Wnt, Hedgehog, Notch, and the interleukin/interferon-gamma/tumor necrosis factor-alpha cytokines, with an emphasis on the underlying molecular mechanisms.
| 19,002,158
|
Gene-mediated restoration of normal myofiber elasticity in dystrophic muscles.
|
Dystrophin mediates a physical link between the cytoskeleton of muscle fibers and the extracellular matrix, and its absence leads to muscle degeneration and dystrophy. In this article, we show that the lack of dystrophin affects the elasticity of individual fibers within muscle tissue explants, as probed using atomic force microscopy (AFM), providing a sensitive and quantitative description of the properties of normal and dystrophic myofibers. The rescue of dystrophin expression by exon skipping or by the ectopic expression of the utrophin analogue normalized the elasticity of dystrophic muscles, and these effects were commensurate to the functional recovery of whole muscle strength. However, a more homogeneous and widespread restoration of normal elasticity was obtained by the exon-skipping approach when comparing individual myofibers. AFM may thus provide a quantification of the functional benefit of gene therapies from live tissues coupled to single-cell resolution.
| 19,002,166
|
Concepts of epigenetics in prostate cancer development.
|
Substantial evidence now supports the view that epigenetic changes have a role in the development of human prostate cancer. Analyses of the patterns of epigenetic alteration are providing important insights into the origin of this disease and have identified specific alterations that may serve as useful diagnostic and prognostic biomarkers. Examination of cancer methylation patterns supports a stem cell origin of prostate cancer. It is well established that methylation of GSTpi is a marker of prostate cancer, and global patterns of histone marking appear to be linked to cancer prognosis with levels of acetylated histones H3K9, H3K18, and H4K12, and of dimethylated H4R3 and H3K4, dividing low-grade prostate cancer (Gleason 6 or less) into two prognostically separate groups. Elevated levels of several components of the polycomb group protein complex, EZH2, BMI1, and RING1, can also act as biomarkers of poor clinical outcome. Many components of the epigenetic machinery, including histone deacetylase (whose expression level is linked to the TMPRSS2:ERG translocation) and the histone methylase EZH2, are potential therapeutic targets. The recent discovery of the role of small RNAs in governing the epigenetic status of individual genes offers exciting new possibilities in therapeutics and chemoprevention.
| 19,002,169
|
Isothiocyanate NB7M causes selective cytotoxicity, pro-apoptotic signalling and cell-cycle regression in ovarian cancer cells.
|
The present report identifies indole-3-ethyl isothiocyanate NB7M as a potent cytotoxic agent with selective activity against cell lines derived from various tumour types. Ovarian cancer cell lines showed sensitivity to NB7M (60-70% cytotoxicity at 2.5 microM), in contrast to control cells (TCL-1 and HTR-8; IC(50) approximately 15 microM). In a screen performed by the National Cancer Institute (NCI) (NCI(60) cancer cell-line assay) NB7M (NSC746077) reduced growth up to 100% with an IC(50) between 0.1 and 10 microM depending on the cell line studied. Using SKOV-3 ovarian cancer cells as a model, mechanisms of cytotoxicity were analysed. NB7M caused hallmarks of apoptosis such as PARP-1 deactivation, chromatin condensation, DNA nicks, activation of caspases-9, -8, -3, loss of mitochondrial transmembrane depolarisation potential and upregulation of pro-apoptotic mitogen activated protein kinases (p38, SAP/JNK). NB7M downregulated phosphorylation of prosurvival kinases (PI-3K, AKT, IKK alpha), transcription factor NF-kappaB, and expression of DNA-Pk and AXL receptor tyrosine kinase. Subcytotoxic doses of NB7M inhibited DNA synthesis, caused G1-phase cell-cycle arrest and upregulated p27 expression. The present report suggests that NB7M is a selective cytotoxic agent in vitro for cell lines derived from ovarian and certain other tumours. In addition, NB7M acts as a growth/cell-cycle-suppressing agent and may be developed as a potential therapeutic drug to treat ovarian cancer.
| 19,002,174
|
Roles of macrophages in flow-induced outward vascular remodeling.
|
Sustained hemodynamic stresses, especially sustained high blood flow, result in flow-induced outward vascular remodeling. Mechanisms that link hemodynamic stresses to vascular remodeling are not well understood. Inflammatory cells, known for their release of proteinases, including matrix metalloproteinases (MMPs), are emerging as key mediators for various tissue remodeling. Using a flow-augmented common carotid artery model in rats, we tested whether macrophages play critical roles in adaptive outward vascular remodeling in response to an increase in blood flow. Left common carotid artery ligation caused a sustained increase in blood flow with a gradual increase in luminal diameter in the right common carotid artery. Macrophages infiltrated into the vascular wall that peaked 3 days after flow augmentation. The time course of MMP-9 expression coincided with infiltration of macrophages. Macrophage depletion by liposome-encapsulated dichloromethylene diphosphonate significantly reduced flow-induced outward vascular remodeling, as indicated by the smaller luminal diameter of flow-augmented right common carotid artery in the clodronate-treated group compared with the phosphate-buffered saline-treated group (P<0.05). These data show critical roles of macrophages in flow-induced outward vascular remodeling. Inflammatory cell infiltration and their subsequent release of cytokines may be key processes for flow-induced outward vascular remodeling.
| 19,002,198
|
Bioelectrical impedance phase angle in constitutionally lean females, ballet dancers and patients with anorexia nervosa.
|
Several articles have described body composition in anorexia nervosa, whereas little is known about this issue in underweight ballet dancers and constitutionally lean females. The main aim of this study was to assess whether phase angle (a bioimpedance variable related to body cell mass) differs according to the type of underweight in female adolescents and young women. Skinfold thicknesses and bioimpedance analysis (whole body and limbs) were evaluated in three groups of underweight patients (30 patients with anorexia nervosa, 10 constitutionally lean individuals and 15 classical dancers) and 30 normal weight controls. There were no differences between the three groups of underweight patients with respect to anthropometric and bioelectrical impedance analysis (BIA) variables with the exception of phase angle. The latter was significantly higher in dancers, lower in anorectic patients and not different in constitutionally lean patients, as compared with controls. Phase angle (assessed by single-frequency BIA) appears to discriminate between different forms of underweight, being an effective marker of qualitative changes in body composition.
| 19,002,201
|
Beam deflection and scanning by two-mirror and two-axis systems of different architectures: a unified approach.
|
An analytical model is developed to predict the structures of the scan fields generated by two-mirror-two-axis beam scanning systems of different architectures, including (1) two oscillating galvanometric scanners, (2) the paddle scanner two-mirror system, and (3) the golf club two-mirror system. It is found that the scan field generated by these systems can be divided into two regions, and scan patterns on the plane of observation depend strongly on the system configuration only in the near-field region. This finding leads to a unified approach to evaluate the structure of scan fields in the far-field region, which paves the way for an investigation of the optical distortions in the scan patterns generated by two-mirror-two-axis beam scanning systems of different architectures.
| 19,002,221
|
Compensating the intensity fall-off effect in cone-beam tomography by an empirical weight formula.
|
The Feldkamp-David-Kress (FDK) algorithm is widely adopted for cone-beam reconstruction due to its one-dimensional filtered backprojection structure and parallel implementation. In a reconstruction volume, the conspicuous cone-beam artifact manifests as intensity fall-off along the longitudinal direction (the gantry rotation axis). This effect is inherent to circular cone-beam tomography due to the fact that a cone-beam dataset acquired from circular scanning fails to meet the data sufficiency condition for volume reconstruction. Upon observations of the intensity fall-off phenomenon associated with the FDK reconstruction of a ball phantom, we propose an empirical weight formula to compensate for the fall-off degradation. Specifically, a reciprocal cosine can be used to compensate the voxel values along longitudinal direction during three-dimensional backprojection reconstruction, in particular for boosting the values of voxels at positions with large cone angles. The intensity degradation within the z plane, albeit insignificant, can also be compensated by using the same weight formula through a parameter for radial distance dependence. Computer simulations and phantom experiments are presented to demonstrate the compensation effectiveness of the fall-off effect inherent in circular cone-beam tomography.
| 19,002,227
|
Absolute testing of the reference surface of a Fizeau interferometer through even/odd decompositions.
|
Absolute testing of spherical surfaces is a technological necessity because of increased accuracy requirements. In a Fizeau setup, the main part of the interferometer deviations thereby comes from the reference surface. We demonstrate the validity of an absolute testing procedure for the reference surface that has been proposed earlier. The procedure relies on the decomposition of the surface deviations into odd and even parts and could be used in partially coherent illumination. The odd deviations are obtained from a basic and a 180 degree-rotated position of an auxiliary sphere, and the even deviations can be measured with the help of a cat's eye position in double pass using an opaque half screen in the interferometer aperture.
| 19,002,239
|
Correlative and dynamic imaging of the hatching biology of Schistosoma japonicum from eggs prepared by high pressure freezing.
|
Schistosome eggs must traverse tissues of the intestine or bladder to escape the human host and further the life cycle. Escape from host tissues is facilitated by secretion of immuno-reactive molecules by eggs and the formation of an intense strong granulomatous response by the host which acts to exclude the egg into gut or bladder lumens. Schistosome eggs hatch on contact with freshwater, but the mechanisms of activation and hatching are poorly understood. In view of the lack of knowledge of the behaviour of egg hatching in schistosomes, we undertook a detailed dynamic and correlative study of the hatching biology of Schistosoma japonicum. Hatching eggs of S. japonicum were studied using correlative light and electron microscopy (EM). The hatching behaviour was recorded by video microscopy. EM preparative methods incorporating high pressure freezing and cryo-substitution were used to investigate ultrastructural features of the miracidium and extra-embryonic envelopes in pre-activated and activated eggs, and immediately after eggshell rupture. Lectin cytochemistry was performed on egg tissues to investigate subcellular location of specific carbohydrate groups. The hatching of S. japonicum eggs is a striking phenomenon, whereby the larva is liberated explosively while still encapsulated within its sub-shell envelopes. The major alterations that occur in the egg during activation are scission of the outer envelope-eggshell boundary, autolysis of the cellular inner envelope, and likely hydration of abundant complex and simple polysaccharides in the lacunal space between the miracidial larva and surrounding envelopes. These observations on hatching provide insight into the dynamic activity of the eggs and the biology of schistosomes within the host.
| 19,002,240
|
Wound-induced endogenous jasmonates stunt plant growth by inhibiting mitosis.
|
When plants are repeatedly injured their growth is stunted and the size of organs such as leaves is greatly reduced. The basis of this effect is not well-understood however, even though it reduces yield of crops injured by herbivory, and produces dramatic effects exemplified in ornamental bonsai plants. We have investigated the genetic and physiological basis of this "bonsai effect" by repeatedly wounding leaves of the model plant Arabidopsis. This treatment stunted growth by 50% and increased the endogenous content of jasmonate (JA), a growth inhibitor, by seven-fold. Significantly, repeated wounding did not stunt the growth of the leaves of mutants unable to synthesise JA, or unable to respond to JA including coi1, jai3, myc2, but not jar1. The stunted growth did not result from reduced cell size, but resulted instead from reduced cell number, and was associated with reduced expression of CycB1;2. Wounding caused systemic disappearance of constitutively expressed JAZ1::GUS. Wounding also activates plant immunity. We show that a gene, 12-oxo-phytodienoate reductase, which catalyses a step in JA biosynthesis, and which we confirm is not required for defence, is however required for wound-induced stunting. Our data suggest that intermediates in the JA biosynthetic pathway activate defence, but a primary function of wound-induced JA is to stunt growth through the suppression of mitosis.
| 19,002,244
|
Campylobacter infection as a trigger for Guillain-Barré syndrome in Egypt.
|
Most studies of Campylobacter infection triggering Guillain-Barré Syndrome (GBS) are conducted in western nations were Campylobacter infection and immunity is relatively rare. In this study, we explored Campylobacter infections, Campylobacter serotypes, autoantibodies to gangliosides, and GBS in Egypt, a country where Campylobacter exposure is common. GBS cases (n = 133) were compared to age- and hospital-matched patient controls (n = 374). A nerve conduction study was performed on cases and a clinical history, serum sample, and stool specimen obtained for all subjects. Most (63.3%) cases were demyelinating type; median age four years. Cases were more likely than controls to have diarrhea (29.5% vs. 22.5%, Adjusted Odds Ratio (ORa) = 1.69, P = 0.03), to have higher geometric mean IgM anti-Campylobacter antibody titers (8.18 vs. 7.25 P<0.001), and to produce antiganglioside antibodies (e.g., anti-Gd1a, 35.3 vs. 11.5, ORa = 4.39, P<0.0001). Of 26 Penner:Lior Campylobacter serotypes isolated, only one (41:27, C. jejuni, P = 0.02) was associated with GBS. Unlike results from western nations, data suggested that GBS cases were primarily in the young and cases and many controls had a history of infection to a variety of Campylobacter serotypes. Still, the higher rates of diarrhea and greater antibody production against Campylobacter and gangliosides in GBS patients were consistent with findings from western countries.
| 19,002,255
|
Genome-scale validation of deep-sequencing libraries.
|
Chromatin immunoprecipitation followed by high-throughput (HTP) sequencing (ChIP-seq) is a powerful tool to establish protein-DNA interactions genome-wide. The primary limitation of its broad application at present is the often-limited access to sequencers. Here we report a protocol, Mab-seq, that generates genome-scale quality evaluations for nucleic acid libraries intended for deep-sequencing. We show how commercially available genomic microarrays can be used to maximize the efficiency of library creation and quickly generate reliable preliminary data on a chromosomal scale in advance of deep sequencing. We also exploit this technique to compare enriched regions identified using microarrays with those identified by sequencing, demonstrating that they agree on a core set of clearly identified enriched regions, while characterizing the additional enriched regions identifiable using HTP sequencing.
| 19,002,256
|
Plasma gelsolin depletion and circulating actin in sepsis: a pilot study.
|
Depletion of the circulating actin-binding protein, plasma gelsolin (pGSN) has been described in septic patients and animals. We hypothesized that the extent of pGSN reduction correlates with outcomes of septic patients and that circulating actin is a manifestation of sepsis. We assayed pGSN in plasma samples from non-surgical septic patients identified from a pre-existing database which prospectively enrolled patients admitted to adult intensive care units at an academic hospital. We identified 21 non-surgical septic patients for the study. Actinemia was detected in 17 of the 21 patients, suggesting actin released into circulation from injured tissues is a manifestation of sepsis. Furthermore, we documented the depletion of pGSN in human clinical sepsis, and that the survivors had significantly higher pGSN levels than the non-survivors (163+/-47 mg/L vs. 89+/-48 mg/L, p = 0.01). pGSN levels were more strongly predictive of 28-day mortality than APACHE III scores. For every quartile reduction in pGSN, the odds of death increased 3.4-fold. We conclude that circulating actin and pGSN deficiency are associated with early sepsis. The degree of pGSN deficiency correlates with sepsis mortality. Reversing pGSN deficiency may be an effective treatment for sepsis.
| 19,002,257
|
Viscous instabilities in flowing foams: a Cellular Potts Model approach.
|
The Cellular Potts Model (CPM) successfully simulates drainage and shear in foams. Here we use the CPM to investigate instabilities due to the flow of a single large bubble in a dry, monodisperse two-dimensional flowing foam. As in experiments in a Hele-Shaw cell, above a threshold velocity the large bubble moves faster than the mean flow. Our simulations reproduce analytical and experimental predictions for the velocity threshold and the relative velocity of the large bubble, demonstrating the utility of the CPM in foam rheology studies.
| 19,002,269
|
A guided abstinence experience to illustrate addiction recovery principles.
|
To develop and implement an elective pharmacy course that included a guided abstinence experience to illustrate addiction recovery principles. A 1-credit elective course to illustrate addiction recovery principles was developed and implemented. The course required students to give up a habit for 6 weeks that was causing them problems, meet weekly to discuss addiction recovery processes, and relate their experiences in a journal. Course grades were determined by class participation, submitted worksheets, and submission of the journal and a paper concerning their role as a pharmacist in dealing with those with addictions and in recovery. Pre- and posttests consisting of addiction case scenarios were used to assess students' application of course material. Graded course elements, pretesting and posttesting, and student course evaluations indicated that course objectives were met. Over the past 15 years, student enrollment has grown from approximately 10% of pharmacy classes to approximately 50% (average 31 students). A guided abstinence experience was an effective tool for teaching pharmacy students the concepts of addiction and recovery.
| 19,002,278
|
Bugs and the big bang.
|
Now that's a cheery thought! Somewhere more than 100 km below the Geneva countryside two parallel beams of subatomic particles are whizzing around a 27 km circuit in opposite directions at about 99% of the speed of light, doing over 11 000 laps per second. Physicists hope to create a 'bang' that won't end the world, but will unlock some of its mysteries. I confess I have never thought of physicists as poets, but they certainly come up with some evocative models to explain the unknown such as 'dark matter', the invisible skeleton stretching through space; or 'dark energy', which drives the expansion of the universe; or the grandiose 'God's particle' (officially named 'Higgs boson') postulated to endow other particles with mass. These are concepts both too large and too small to grasp.
| 19,002,295
|
Red flags in scleroderma.
|
Scleroderma (systemic sclerosis) is an uncommon connective tissue disease characterised by vascular, inflammatory and fibrotic dysfunction of multiple organ systems. Systemic sclerosis is often recognised late in the course of the disease. This article outlines the clinical features of systemic sclerosis, in particular 'red flags' that indicate the presence of significant organ disease. Common clinical features include Raynaud phenomenon and skin thickening, often with calcinosis and telangiectasia. These features should alert the physician to look for red flag features. In the general practice setting, early recognition of scleroderma will enable timely referral to specialist centres for regular screening and effective management of its many serious visceral complications.
| 19,002,303
|
Trapped in the net? What to look for in a web based CPD program.
|
Increasing numbers of general practitioners access web based education programs for continuing professional development (CPD). Web based programs vary in style, content, relevance, reliability, authorship and sponsorship, and hence educational quality. This article outlines how to choose a web based CPD program. Busy GPs need to maximise their time by enrolling in effective CPD programs. Effective web based education programs implement educational theory on adult learning and the development of clinical competence.
| 19,002,305
|
Desire for research in general practice.
|
If you have considered participating in general practice research, the chances are that a combination of inherent interest and potential satisfaction drew you toward it. You may want to see the evidence base of general practice expanded; you probably enjoy an intellectual challenge; and you are likely to take pleasure in the sense of achievement this can bring.
| 19,002,311
|
GP management of osteoarthritic pain in Hong Kong.
|
Limited information is available about general practitioners' knowledge, attitude and practice in treating osteoarthritis. This study sought to better understand GPs' management of mild to moderate osteoarthritis in Hong Kong. A cross sectional survey of GPs using a structured questionnaire mailed in three stages. A total of 225 questionnaires were returned. Paracetamol was considered to be an analgesic with lower toxicity and cost, and fewer drug interactions than others; it was also seen to have poor efficacy, short duration of action, and low patient compliance. Most GPs would consider nonselective nonsteroidal anti-inflammatory drugs as first line treatment, followed by paracetamol. Cyclooxygenase-2 inhibitors, physiotherapy and exercise were favoured as second line treatments. Most GPs would choose paracetamol for patients with comorbid conditions. General practitioners in Hong Kong have positive views on using simple analgesia and nonpharmacological treatments. Use of paracetamol was particularly preferred for older people and those with comorbidities.
| 19,002,312
|
Rh(I) and Ir(I) catalysed intermolecular hydroamination with substituted hydrazines.
|
The catalysed intermolecular hydroamination of a series of terminal alkynes with substituted hydrazines was achieved using Rh(I) and Ir(I) complexes.
| 19,002,322
|
Sweet's syndrome: a retrospective clinical, histopathological and immunohistochemical analysis of 11 cases.
|
The aim of this paper is to report our clinical experience of Sweet's syndrome, a severe dermatological disease which may be extremely important to recognize for the early diagnosis of a neoplastic disorder. Eleven patients affected by Sweet's syndrome, treated at the Department of Dermatology, University of Ferrara, Ferrara, Italy, during 1998 to 2004, were evaluated. A retrospective analysis was performed. Data on age, sex distribution, clinical data, histopathological and immunohistochemical findings and therapy were collected. We observed one patient with idiopathic form, 5 patients affected by the para-inflammatory variant and 5 para-neoplastic cases (with haemoproliferative diseases). The cases with the para-inflammatory form were affected by minor infectious manifestations. Prolonged follow-up is necessary to verify that a case of idiopathic variant is not really a paraneoplastic form. Based on immunohistochemical analysis, we cannot exclude that true histiocytes, immunoreactive for CD68/PGM, infiltrate the dermis in Sweet's syndrome lesions.
| 19,002,347
|
A modification of Labhardt's high perineoplasty for treatment of pelvic organ prolapse in the very old.
|
A new simple colpocleisis technique is introduced for the treatment of pelvic organ prolapse in the very old acoital patient with extensive co-morbidity and enhanced intra-operative risk. The method is described and can be performed under local anesthesia. Main outcome measure was patient's satisfaction. Thirty patients were evaluated by means of a questionnaire at least 6 months after the operation. Generally, most patients were very satisfied and none of the patients regretted the operation. This modification of Labhardt's high perineoplasty is an elegant solution for pelvic organ prolapse in elderly acoital women regardless of the type of prolapse.
| 19,002,368
|
Analysis of intracranial pressure changes during early versus late percutaneous tracheostomy in a neuro-intensive care unit.
|
We aimed to investigate intracranial pressure (ICP) changes during early versus late bedside percutaneous tracheostomy (PT) in a neuro-intensive care unit (NICU). This study included 30 patients admitted to our NICU for head trauma, subarachnoid haemorrhage, intracerebral haematoma or brain tumour with a Glasgow Coma Score (GCS) less than 8. These patients also underwent ICP monitoring. Bedside PT was performed either early (within 7 days of ventilation) or late (after 7 days of ventilation) via the Griggs system. In all patients; ICP, systemic blood pressure, heart rate, oxygen saturation (Sat O(2)) and arterial blood gases were recorded 5 min before the procedure, during skin incision, during tracheal cannulation, as well as 5 min and 10 min after the procedure. Thirty patients, 18 male and 12 female, with various intracranial pathologies between ages 18 and 78 (mean 38.7 +/- 20) were identified. The admission GCS ranged between 4 and 11 (median 7). Physiological variables did not differ significantly between the two groups. In the early group, ICP values measured 5 min before the procedure, during skin incision, during tracheal cannulation, as well as 5 min and 10 min after the procedure were 15.1 +/- 5.2, 22 +/- 10.1, 28.4 +/- 13.7, 17.3 +/- 7.1, 13.8 +/- 5.0 mmHg, respectively. In the late group, these values were 14.2 +/- 4.5, 17.2 +/- 5.5, 21.5 +/- 8.0, 15.1 +/- 5.3 and 12.4 +/- 4.1 mmHg. There was no significant difference between the early or late groups in terms of ICP increases during these predetermined 5 time points. In patients with decreased intracranial compliance, a relatively minimally invasive procedure such as PT may lead to significant increases in ICP. The timing of PT does not seem to influence ICP, mortality, pneumonia or early complications. During the PT procedure, ICP should be closely monitored and preventive strategies should be instituted in an attempt to prevent secondary insult to an already severely injured brain.
| 19,002,373
|
Hydroxylation of demethoxy-Q6 constitutes a control point in yeast coenzyme Q6 biosynthesis.
|
Coenzyme Q is a lipid molecule required for respiration and antioxidant protection. Q biosynthesis in Saccharomyces cerevisiae requires nine proteins (Coq1p-Coq9p). We demonstrate in this study that Q levels are modulated during growth by its conversion from demethoxy-Q (DMQ), a late intermediate. Similar conversion was produced when cells were subjected to oxidative stress conditions. Changes in Q(6)/DMQ(6) ratio were accompanied by changes in COQ7 gene mRNA levels encoding the protein responsible for the DMQ hydroxylation, the penultimate step in Q biosynthesis pathway. Yeast coq null mutant failed to accumulate any Q late biosynthetic intermediate. However, in coq7 mutants the addition of exogenous Q produces the DMQ synthesis. Similar effect was produced by over-expressing ABC1/COQ8. These results support the existence of a biosynthetic complex that allows the DMQ(6) accumulation and suggest that Coq7p is a control point for the Q biosynthesis regulation in yeast.
| 19,002,377
|
Calcium, magnesium, iron, zinc and copper concentration in the hair of tobacco smokers.
|
In the research, the content of bioelements (Ca, Mg, Fe, Zn, and Cu) in the hair of individuals who reside in similar environmental conditions was spectrometrically determined with the use of AES-ICP spectrophotometer. The relation to their tobacco-smoking habit, age, and sex was established. It was observed that the results obtained were in the range of the content identified for the Polish population. Tobacco smokers had a decreased content of all the bioelements in question, compared to non-smokers, which apparently resulted from a decreased supply (lesser appetite) and reduced absorption caused by disturbances in the digestive system functions. Also, it has been observed that in the group of elderly people, over 50 years old, there was a fall in the content of calcium, magnesium, and iron both in smokers and non-smokers, irrespective of their sex. The sex-related differences in the content of the investigated elements were not unidirectional and only in few cases did they reveal statistical significance.
| 19,002,389
|
Biodegradation of crosslinked acrylic polymers by a white-rot fungus.
|
Two synthetic superabsorbent crosslinked acrylic polymers were mineralized by the white-rot fungus Phanerochaete chrysosporium. The amount of polymer converted to CO(2) increased as the amount of polymer added to the cultures increased. In the presence of sufficiently large amounts of the superabsorbents, such that all of the culture fluid was absorbed and a gelatinous matrix was formed, the fungus still grew and mineralization was observed. Neither the polymers, nor their degradation products were toxic to the fungus. While the rates of mineralization were low, all of the polymers incubated in the liquid fungal cultures were completely depolymerized to water soluble products within 15-18 days. The depolymerization of the polymers was observed only in nitrogen limited cultures of the fungus which secrete the lignin degradation system, however, the water soluble products of depolymerization were mineralized in both nutrient limited and sufficient cultures of the fungus. The rate of mineralization of the depolymerized metabolites was more than two times greater in nutrient sufficient cultures. Following longer incubation periods, most (> 80 %) of the radioactivity was recovered in the fungal mycelial mat suggesting that carbon of the polymer had been converted to fungal metabolites.
| 19,002,412
|
[Positioning of the patient for surgery].
|
The success of an operation does not only depend on a perfect surgical technique, an appropriate anesthesia, convenient surgical instruments and functional technical equipment, but also on a proper operative positioning. Meeting the requirements of the surgeon, the positioning has also to be in accordance with the patient's individual needs. Seemingly trivial in "simple" positions, there must be paid attention to details, as they can have serious harm to the patient if done incorrectly. The surgeon is in charge for the positioning, but the performance is done in a horizontal division of work between surgeon and anesthesiologist. This article describes standard positions, demonstrates their realization and special damages, and points out juristic aspects as well as technical items like operating table and positioning facilities.
| 19,002,419
|
IL-1beta-induced chemokine and Fas expression are inhibited by suppressor of cytokine signalling-3 in insulin-producing cells.
|
Chemokines recruit activated immune cells to sites of inflammation and are important mediators of insulitis. Activation of the pro-apoptotic receptor Fas leads to apoptosis-mediated death of the Fas-expressing cell. The pro-inflammatory cytokines IL-1beta and IFN-gamma regulate the transcription of genes encoding the Fas receptor and several chemokines. We have previously shown that suppressor of cytokine signalling (SOCS)-3 inhibits IL-1beta- and IFN-gamma-induced nitric oxide production in a beta cell line. The aim of this study was to investigate whether SOCS-3 can influence cytokine-induced Fas and chemokine expression in beta cells. Using a beta cell line with inducible Socs3 expression or primary neonatal rat islet cells transduced with a Socs3-encoding adenovirus, we employed real-time RT-PCR analysis to investigate whether SOCS-3 affects cytokine-induced chemokine and Fas mRNA expression. The ability of SOCS-3 to influence the activity of cytokine-responsive Fas and Mcp-1 (also known as Ccl2) promoters was measured by reporter analysis. IL-1beta induced a time-dependent increase in Mcp-1 and Mip-2 (also known as Cxcl2) mRNA expression after 6 h of stimulation in insulinoma (INS)-1 and neonatal rat islet cells. This induction was inhibited when Socs3 was expressed in the cells. In INS-1 cells, IL-1beta + IFN-gamma induced a tenfold and eightfold increase of Fas mRNA expression after 6 and 24 h, respectively. This induction was inhibited at both time-points when expression of Socs3 was induced. In promoter studies SOCS-3 significantly inhibited the cytokine-induced activity of Mcp-1 and Fas promoter constructs. SOCS-3 inhibits the expression of cytokine-induced chemokine and death-receptor Fas mRNA.
| 19,002,429
|
Effects of gabapentin and pregabalin on K+-evoked 3H-GABA and 3H-glutamate release from human neocortical synaptosomes.
|
One site of action of the anticonvulsant, analgesic, and anxiolytic drugs gabapentin and pregabalin is the alpha(2)delta-subunit of voltage-sensitive Ca(2+) channels (VSCC). We therefore analyzed the effects of gabapentin and pregabalin on K(+)-evoked release of (3)H-gamma-aminobutyric acid (GABA) and (3)H-glutamate from superfused human neocortical synaptosomes. These neurotransmitters are released by Ca(2+)-dependent exocytosis and by Ca(2+)-independent uptake reversal. When a GABA transport inhibitor was present throughout superfusion to isolate exocytotic conditions, gabapentin and pregabalin (100 microM each) reduced K(+)-evoked (3)H-GABA release by 39% and 47%, respectively. These effects were antagonized by the alpha(2)delta-ligand L: -isoleucine (1 microM) suggesting the alpha(2)delta-subunit of terminal VSCC to mediate the reduction of exocytosis. Both drugs had no effect on exocytotic (3)H-glutamate release and also failed to modulate the release of (3)H-GABA and (3)H-glutamate caused by reversed uptake in the absence of external Ca(2+). Thus, an inhibition of glutamate release by gabapentin and pregabalin as main anticonvulsant principle is not supported by our experiments. An anticonvulsant mode of action of both drugs may be the reduction of a proconvulsant exocytotic GABA release.
| 19,002,437
|
Capillary waveguide fluoroimmunosensor with improved repeatability and detection sensitivity.
|
An optical capillary waveguide fluoroimmunosensor based on glass capillaries internally coated with an ultrathin poly(dimethylsiloxane) (PDMS) film is presented. The evaluation of the capillaries developed was done in comparison with aminosilanized [3-(aminopropyl)triethoxysilane, APTES] glass and poly(methylpentene) (PMP) capillaries by immobilizing rabbit gamma-globulins on the internal capillary wall. Following reaction with (R)-phycoerythrin-labelled antibody, the capillary was scanned with a laser beam and the fluorescence waveguided through the capillary wall was detected by a photomultiplier placed at one of its ends. The capillaries developed provided considerably improved protein coating homogeneity (intracapillary coefficients of variation 2.9-6.6%) and repeatability (intercapillary coefficients of variation 2.1-5.0%) compared with APTES-treated ones (7.9-13.4 and 8.5-15.2%, respectively). With use of these capillaries in a sandwich-type immunosensor for the determination of rabbit gamma-globulins, the assay detection limit was improved eightfold (4.4 ng/mL) compared with that obtained using PMP capillaries (35.3 ng/mL), whereas the assay repeatability was improved threefold (intra-assay coefficients of variation 5.9-13.1%) compared with APTES-treated capillaries (15.6-36%).
| 19,002,440
|
Strategies for PHA production by mixed cultures and renewable waste materials.
|
Production of polyhydroxyalkanoates (PHA) by mixed cultures has been widely studied in the last decade. Storage of PHA by mixed microbial cultures occurs under transient conditions of carbon or oxygen availability, known respectively as aerobic dynamic feeding and anaerobic/aerobic process. In these processes, PHA-accumulating organisms, which are quite diverse in terms of phenotype, are selected by the dynamic operating conditions imposed to the reactor. The stability of these processes during long-time operation and the similarity of the polymer physical/chemical properties to the one produced by pure cultures were demonstrated. This process could be implemented at industrial scale, providing that some technological aspects are solved. This review summarizes the relevant research carried out with mixed cultures for PHA production, with main focus on the use of wastes or industrial surplus as feedstocks. Basic concepts, regarding the metabolism and microbiology, and technological approaches, with emphasis on the kind of feedstock and reactor operating conditions for culture selection and PHA accumulation, are described. Challenges for the process optimization are also discussed.
| 19,002,455
|
The liver and kidney expression of sulfate anion transporter sat-1 in rats exhibits male-dominant gender differences.
|
The sulfate anion transporter (sat-1, Slc26a1) has been cloned from rat liver, functionally characterized, and localized to the sinusoidal membrane in hepatocytes and basolateral membrane (BLM) in proximal tubules (PT). Here, we confirm previously described localization of sat-1 protein in rat liver and kidneys and report on gender differences (GD) in its expression by immunochemical, transport, and excretion studies in rats. The approximately 85-kDa sat-1 protein was localized to the sinusoidal membrane in hepatocytes and BLM in renal cortical PT, with the male-dominant expression. However, the real-time reverse-transcription polymerase chain reaction data indicated no GD at the level of sat-1 mRNA. In agreement with the protein data, isolated membranes from both organs exhibited the male-dominant exchange of radiolabeled sulfate for oxalate, whereas higher oxalate in plasma and 24-h urine indicated higher oxalate production and excretion in male rats. Furthermore, the expression of liver, but not renal, sat-1 protein was: unaffected by castration, upregulated by ovariectomy, and downregulated by estrogen or progesterone treatment in males. Therefore, GD (males > females) in the expression of sat-1 protein in rat liver (and, possibly, kidneys) are caused by the female sex-hormone-driven inhibition at the posttranscriptional level. The male-dominant abundance of sat-1 protein in liver may conform to elevated uptake of sulfate and extrusion of oxalate, causing higher plasma oxalate in males. Oxalate is then excreted by the kidneys via the basolateral sat-1 (males > females) and the apical CFEX (Slc26a6; GD unknown) in PT and eliminated in the urine (males > females), where it may contribute to the male-prevailing development of oxalate urolithiasis.
| 19,002,488
|
Are the birch trees in Southern England a source of Betula pollen for North London?
|
Birch pollen is highly allergenic. Knowledge of daily variations, atmospheric transport and source areas of birch pollen is important for exposure studies and for warnings to the public, especially for large cities such as London. Our results show that broad-leaved forests with high birch tree densities are located to the south and west of London. Bi-hourly Betula pollen concentrations for all the days included in the study, and for all available days with high birch pollen counts (daily average birch pollen counts>80 grains/m3), show that, on average, there is a peak between 1400 hours and 1600 hours. Back-trajectory analysis showed that, on days with high birch pollen counts (n=60), 80% of air masses arriving at the time of peak diurnal birch pollen count approached North London from the south in a 180 degree arc from due east to due west. Detailed investigations of three Betula pollen episodes, with distinctly different diurnal patterns compared to the mean daily cycle, were used to illustrate how night-time maxima (2200-0400 hours) in Betula pollen counts could be the result of transport from distant sources or long transport times caused by slow moving air masses. We conclude that the Betula pollen recorded in North London could originate from sources found to the west and south of the city and not just trees within London itself. Possible sources outside the city include Continental Europe and the Betula trees within the broad-leaved forests of Southern England.
| 19,002,505
|
Pain palliation in patients with bone metastases using MR-guided focused ultrasound surgery: a multicenter study.
|
Noninvasive thermal ablation using magnetic resonance (MR)-guided focused ultrasound (MRgFUS) has been shown to be clinically effective in uterine fibroids, and is being evaluated for ablation of breast, liver, and brain lesions. Recently MRgFUS has been evaluated for palliation of pain caused by bone metastases. We present the clinical results of a multicenter study using MRgFUS for palliation of bone metastases pain. A multicenter study to evaluate the safety and efficacy of MRgFUS palliative treatment of bone metastases was conducted in patients suffering from painful metastatic bone lesions for which other treatments were either ineffective or not feasible. Thirty-one patients with painful bone metastases underwent the MRgFUS procedure in three medical centers. Treatment safety was evaluated by assessing the device-related complications. Effectiveness of pain palliation was evaluated using the visual analog pain score (VAS), and measurable changes in the intake of opioid analgesics. Thirty-six procedures were performed on 31 patients. Mean follow-up time was 4 months. 25 patients underwent the planned treatment and were available for 3 months post-treatment follow-up. 72% of the patients (18/25) reported significant pain improvement. Average VAS score was reduced from 5.9 prior to treatment to 1.8 at 3 months post treatment. 67% of patients with recorded medication data reported a reduction in their opioid usage. No device-related severe adverse events were recorded. The results suggest that MRgFUS has the ability to provide an accurate, effective, and safe noninvasive palliative treatment for patients with bone metastases.
| 19,002,530
|
Surgical site infections following colorectal surgery in patients with diabetes: association with postoperative hyperglycemia.
|
Postoperative glycemic control reduces sternal infections following cardiac surgery in patients with diabetes mellitus (DM). The objective of this study was to examine the relationship between postoperative glycemic control and surgical site infections (SSI) in patients with DM undergoing colorectal resection. A cohort of patients with DM who underwent colorectal resection (April 2001-May 2006) at our institution were reviewed. SSI were defined by Centers for Disease Control criteria. From a study cohort of 149 patients, 24% had poor postoperative glycemic control (defined as a mean 48-h postoperative capillary glucose (MCG) >11.0 mmol/L or 200 mg/dL), and these patients developed SSI at a significantly higher rate than those with a 48-h MCG < or =11.0 mmol/L (29.7% vs. 14.3%; odds ratio (OR) 2.5, p = 0.03). On multivariate logistic regression, 48-h MCG >11.0 mmol/L was significantly associated with SSI (OR 3.6, p = 0.02), independent of the dose and regimen of postoperative insulin administration. In conclusion, 48-h MCG >11.0 mmol/L (200 mg/dL) was independently associated with increased SSI following colorectal resection in patients with DM. Prospective studies are required to validate this relationship, address the role of preoperative glycemic control, and examine strategies to improve glycemic control following colorectal resection.
| 19,002,535
|
The regulation of medical malpractice in Japan.
|
How Japanese legal and social institutions handle medical errors is little known outside Japan. For almost all of the 20th century, a paternalistic paradigm prevailed. Characteristics of the legal environment affecting Japanese medicine included few attorneys handling medical cases, low litigation rates, long delays, predictable damage awards, and low-cost malpractice insurance. However, transparency principles have gained traction and public concern over medical errors has intensified. Recent legal developments include courts' adoption of a less deferential standard of informed consent; increases in the numbers of malpractice claims and of practicing attorneys; more efficient claims handling by specialist judges and speedier trials; and highly publicized criminal prosecutions of medical personnel. The health ministry is undertaking a noteworthy "model project" to enlist impartial specialists in investigation and analysis of possible iatrogenic hospital deaths to regain public trust in medicine's capacity to assess its mistakes honestly and to improve patient safety and has proposed a nationwide peer review system based on the project's methods.
| 19,002,542
|
Targeted delivery of PSC-RANTES for HIV-1 prevention using biodegradable nanoparticles.
|
Nanoparticles formulated from the biodegradable co-polymer poly(lactic-co-glycolic acid) (PLGA), were investigated as a drug delivery system to enhance tissue uptake, permeation, and targeting for PSC-RANTES anti-HIV-1 activity. PSC-RANTES nanoparticles formulated via a double emulsion process and characterized in both in vitro and ex vivo systems to determine PSC-RANTES release rate, nanoparticle tissue permeation, and anti-HIV bioactivity. Spherical, monodisperse (PDI = 0.098 +/- 0.054) PSC-RANTES nanoparticles (d = 256.58 +/- 19.57 nm) with an encapsulation efficiency of 82.23 +/- 8.35% were manufactured. In vitro release studies demonstrated a controlled release profile of PSC-RANTES (71.48 +/- 5.25% release). PSC-RANTES nanoparticle maintained comparable anti-HIV activity with unformulated PSC-RANTES in a HeLa cell-based system with an IC(50) of approximately 1pM. In an ex vivo cervical tissue model, PSC-RANTES nanoparticles displayed a fivefold increase in tissue uptake, enhanced tissue permeation, and significant localization at the basal layers of the epithelium over unformulated PSC-RANTES. These results indicate that PSC-RANTES can readily be encapsulated into a PLGA nanoparticle drug delivery system, retain its anti-HIV-1 activity, and deliver PSC-RANTES to the target tissue. This is crucial for the success of this drug candidate as a topical microbicide product.
| 19,002,569
|
Primary immunodeficiency diseases in Egyptian children: a single-center study.
|
Sixty-four primary immunodeficiency patients were registered at the Pediatric Allergy and Immunology Department, Children's Hospital, Ain Shams University, Cairo, Egypt. Predominantly antibody deficiencies were the most common category (35.9%) followed by combined T- and B-cell immunodeficiencies (29.7%), other well defined immunodeficiency syndromes (18.7%), congenital defects of phagocyte number, function or both (12.5%), and diseases of immune dysregulation (3.1%). The most frequent disorder was common variable immunodeficiency (18.7%). The mean age at diagnosis was 29.9 months. The consanguinity rate was 62.5%. Recurrent severe infections were seen in all categories. Fifteen patients died (23.4%) from infections with the highest mortality for combined T- and B-cell immunodeficiencies (15.6%). Primary immunodeficiency disorders are not rare in Egyptian children. The observed frequency of combined T- and B-cell immunodeficiencies in our cohort is relatively higher than other countries. It is a prerequisite to establish a national registry of primary immunodeficiency in Egypt.
| 19,002,574
|
Oscillatory perfusion culture of CaP-based tissue engineering bone with and without dexamethasone.
|
Dexamethasone, a powerful osteogenic agent for osteoblast differentiation, has been suggested to have synergistic effects when applied together with perfusion culture. As ceramic scaffolds are widely used clinically and oscillatory flow well replicates the natural physical conditions, the biological effects of dexamethasone on oscillatory perfusion culture of CaP-based tissue engineering bone were investigated in this study. Mouse osteoblast-like cells, MC 3T3-E1, were seeded onto porous ceramic scaffolds using the oscillatory perfusion method. The seeded constructs were then either cultured by a static method or an oscillatory perfusion method at different flow rates continuously for 6 days with and without dexamethasone. The cell proliferation, early osteogenic effects, and viability were subsequently evaluated. The results showed that the oscillatory flow could enhance early osteogenesis of osteoblast-like cells in three-dimensional culture on ceramic scaffolds, with a peak function at the flow rate of 0.5 mL/min. The cell viability was significantly higher and more uniform in the perfusion groups than in the static culture groups. The uniformity decreased as the perfusion rates decreased. However, dexamethasone seems to have had no significant effects in any of the groups. Our results suggest that dexamethasone is not an efficient osteogenic supplement during perfusion culture on CaP ceramic scaffolds, and predifferentiation before seeding or additional osteogenic factors should be considered for such cultures.
| 19,002,585
|
Transport and dynamics of toxic pollutants in the natural environment and their effect on human health: research gaps and challenge.
|
The source-pathway-receptor (SPR) approach to human exposure and risk assessment contains considerable uncertainty when using the refined modelling approaches to pollutant transport and dispersal, not least in how compounds of concern might be prioritized, proxy or indicator substances identified and the basic environmental and toxicological data collected. The impact of external environmental variables, urban systems and lifestyle is still poorly understood. This determines exposure of individuals and there are a number of methods being developed to provide more reliable spatial assessments. Within the human body, the dynamics of pollutants and effects on target organs from diffuse, transient sources of exposure sets ambitious challenges for traditional risk assessment approaches. Considerable potential exists in the application of, e.g. physiologically based pharmacokinetic (PBPK) models. The reduction in uncertainties associated with the effects of contaminants on humans, transport and dynamics influencing exposure, implications of adult versus child exposure and lifestyle and the development of realistic toxicological and exposure data are all highlighted as urgent research needs. The potential to integrate environmental with toxicological models provides the next phase of research opportunity and should be used to drive empirical and model assessments.
| 19,002,593
|
Progress in herbicide determination with the thylakoid bioassay.
|
Chloroplast thylakoids are used as biological units to determine herbicides in different kinds of water samples as well as in aqueous extracts of compost, soil or food samples. The thylakoid bioassay shows clearly inhibition of fluorescence yield in the presence of photosystem II specific herbicides. Due to this method the ecotoxicological effect of samples with unknown pollutants can be tested fast and cost effective. It has been proven that all photosynthetic active compounds are recorded at the same time because only additive interactions occur. Therefore, the contamination level can be expressed as cumulative parameter for photosystem II active substances. Application was improved clearly by the addition of the radical scavenger sodium ascorbate to the isolation media and by a higher concentration of the measuring medium. A new data evaluation method is described yielding in a lower detection limit of 0.4 microg diuron/1. The guidelines for the quality of water for human consumption with an allowable concentration of pesticides in groups is 0,5 microg/1 and can be controlled with the thylakoid bioassay without performing any preconcentration steps.
| 19,002,623
|
Toxicity testing of heavy metals with the Rhizobium-legume symbiosis: High sensitivity to cadmium and arsenic compounds.
|
Legume root nodules are the site of biological nitrogen fixation in the Rhizobium-legume symbiosis. Nodules are structures unique to this symbiosis and they are morphologically as well as physiologically distinct from other plant organs. Organic substances affecting the macro- or microsymbionts vitality, such as PAHs (WETZEL: et al., 1991), reduce nodulation even before visible damage to the plant can be detected. We present data that the formation of nodules (nodulation) may also serve for ecotoxicological evaluation of heavy metals in different binding states. Tests were performed in petri dishes with alfalfa (lucerne) seedlings inoculated with Rhizobium meliloti. Cultivation took place in growth cabinets with carefully standardized and documented growth conditions. Data from stressed plants was recorded after 14 days of cultivation on contaminated substrate. A dose responsive decrease in nodulation was found after application of cadmium acetate, cadmium iodide, cadmium chloride, sodium salts of arsenate and arsenite, arsenic pentoxide, and lead nitrate, whereas lead acetate showed no effect up to a concentration of 3 microM. The dose response curves were used to calculate EC10, EC50 and EC90 values. EC50 values for cadmium compounds range from 1.5 to 9.5 pM. Testing different arsenic compounds results in EC50 from 2.6 to 20.1 microM. EC50 of lead nitrate is 2.2 microM. The sensitivity, reproducibility and reliability of this test system is discussed compared to established biotests.
| 19,002,625
|
Distribution of 14C-TNT and derivatives in different biochemical compartments of Phaseolus vulgaris.
|
(14)C-TNT was used to quantify the uptake rate and metabolic turnover of TNT in Phaseolus vulgaris. Seventeen plants were analysed by a special cell fractionation method with polar and nonpolar solvents and enzymes. We obtained three cytoplasmic fractions and five cell wall derived fractions. The recovery rate was 72% as measured by liquid scintillation counting. (14)C partitioned almost in equal amounts with approximately 50% in the cytoplasm and in the cell wall. The majority of the TNT-metabolites are present in the cytoplasm as was shown by GC/ECD and thin layer chromatography. The(14)C in the cell wall is bound probably resulting in long-term immobilisation of these metabolites. We conclude that plants may also be a model for nitroaromatic turnover and immobilisation in soil components.
| 19,002,633
|
Sources of anthropogenic platinum-group elements (PGE): Automotive catalysts versus PGE-processing industries.
|
Soil samples from the area of Hanau (Hessen, Germany) were analyzed for anthropogenic platinum-group elements (PGE). The results confirm the existence of two different sources for anthropogenic PGE: 1. automotive catalysts, and 2. PGE-processing plants. Both sources emit qualitatively and quantitatively different PGE spectra and PGE interelemental ratios (especially the Pt/Rh ratio). Elevated PGE values which are due to automotive catalysts are restricted to a narrow-range along roadside soil, whereas those due to PGE-processing plants display a large-area dispersion. The emitted PGE-containing particles in the case of automotive catalysts are subject to transport by wind and water, whereas those from PGE-processing plants are preferably transported by wind. This points to a different aerodynamic particle size. Pt, Pd, and Rh concentrations along motorways are dependent on the amount of traffic and the driving characteristics.
| 19,002,636
|
Pharmacotherapy of urinary incontinence.
|
The pathophysiology of urinary incontinence (UI) involves an overactive detrusor (DOA) or an incompetent urethral sphincter. Therefore, the three most common types of UI are stress urinary incontinence (SUI), urge urinary incontinence (UUI), or a combination of stress and urge known as mixed urinary incontinence (MUI). Pharmacotherapy represents a recognized option for the treatment of different types of UI. A literature search of Medline publications on pharmacological treatment of urinary incontinence until 2008 was performed. Relevant data from recently published literature were included. Anticholinergics are the cornerstone of UUI treatment, whereas serotonin and norepinephrine re-uptake inhibitors represent an option for SUI treatment. A significant percentage of patients with UI, mainly those with UUI and MUI, can be treated successfully with pharmacotherapy.
| 19,002,644
|
Improved ethanol production by mixed immobilized cells of Kluyveromyces marxianus and Saccharomyces cerevisiae from cheese whey powder solution fermentation.
|
Ethanol productions from cheese whey powder (CWP) solution were investigated by using free or immobilized cells of Kluyveromyces marxianus in monocultures or mixed cultures with free or immobilized cells of K. marxianus and Saccharomyces cerevisiae. K. marxianus free cells produced 3.8% v/v ethanol in monocultures, while S. cerevisiae immobilized cells produced 5.3% v/v ethanol in mixed cultures. The percentage of theoretical yield was found to be higher in mixed cultures than that in monocultures. The maximum ethanol fermentation efficiency was achieved (79.9% of the theoretical value) using mixed cultures of immobilized cells of K. marxianus and S. cerevisiae. The beads were relatively stable without significant reduction in activity for about eight batches of fermentation.
| 19,002,658
|
[Effective acquisition of basic surgical techniques through blended learning].
|
Large student numbers and heterogeneous teaching pools hamper standardized teaching and impede objective assessment of surgical skills. This article presents the advantages of new teaching media in a "blended learning" concept for training surgical skills to medical students at the Basel University Medical School in Switzerland. The surgical skills course (suture course) for medical students was redesigned according to a blended learning concept consisting of an introduction with a multimedia CD-ROM, a practical course, and a skills lab. The learning targets of the course were evaluated through an objective structured clinical examination (OSCE) at the end of each study year. The students' own course evaluations were compared with the OSCE results before and after introduction of the new blended learning. The students' evaluations with regard to teaching material, subjective practical achievement, prospective value for the practical year, and overall course evaluation were significantly higher than in the old course format. The proportion of passed OSCEs was 10% higher after the redesign of the course. Blended learning can improve cognition and performance as well as the training efficiency and duration required for mentoring. Thus human resources can be saved indirectly. Surgical procedures may be presented more clearly.
| 19,002,661
|
An analysis of outcome of arthroscopic versus mini-open rotator cuff repair using subjective and objective scoring tools.
|
The purpose is to perform a comparative analysis of mini-open and arthroscopic rotator cuff repairs through the use of subjective and objective scoring tools. We conducted a prospective comparative cohort study that evaluated 123 consecutive patients who underwent rotator cuff repairs (arthroscopic and 31 mini-open repair). Subjective and objective functional assessment was performed preoperatively and postoperatively at 3, 6, 12, 18 and 24 months using the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, the Oxford Shoulder Score (OSS) and the Constant-Murley score. Statistical analysis was performed on the datasets assessing the Pearson correlation coefficients and any significant differences present at each respective time point. At every time point the arthroscopic group scored better than the mini-open group, regardless of the assessment tool employed. The percentage recovery from the baseline measured at 1 year was similar with either treatment option. A significant difference was found between the arthroscopic and mini-open groups for the Constant-Murley, DASH and OSS scoring systems preoperatively (P < 0.05), reflecting a difference in tear severity. Arthroscopic rotator cuff repair is comparable with the mini-open technique with well correlated postoperative rates recovery. Subjective scoring provides an accurate and potentially easier method of postoperative assessment for long-term follow-up of rotator cuff repairs.
| 19,002,667
|
How critical is the use of commercially available enzymes for selenium speciation?
|
The aim of this work was to check whether commercially available enzymes are pure enough to be used for selenium speciation analysis and the contribution that impurities could make to Se determination in real samples. For this purpose, twelve commercially available enzymes with different origins and classifications (protease, amylase, cellulase, lipase) were analysed. After the dissolution of the enzyme in water, the Se species were separated by ion exchange chromatography, with inductively coupled plasma mass spectrometry used as the detection system. The results showed that the Se content was significant in several cases. The highest value was obtained for beta-amylase from barley, 3100 ng Se per g of enzyme. Speciation analysis showed that Se-methionine, selenite, selenate and some unknown compounds were present in several enzymes. In general, the Se species identified represented a small fraction of the total Se. For instance, only 17% of the total Se was determined for beta-amylase from barley. On the other hand, about 100% of the total Se was identified in protease from Streptomyces griseus. Upon comparing the results from different lots of the same enzyme, not all of them were found to be comparable. Thus, the presence of selenium species in commercially available enzymes could be due to the preparation procedure used for the enzyme; they could be present as degradation products. Therefore, when determining selenium species in samples with low Se contents, attention should be paid to enzyme purity in relation to selenium compounds when an enzyme is used for hydrolysis.
| 19,002,673
|
Does reflux in orthotopic diversion matter? A randomized prospective comparison of the Studer and T-pouch ileal neobladders.
|
Orthotopic neobladder reconstruction has become a standard form of urinary diversion in many centers for patients undergoing radical cystectomy for bladder cancer. There is still controversy about the best technique for construction of the neobladder, and especially whether it is necessary to include an antireflux mechanism. We designed a prospective randomized clinical trial comparing two forms of ileal neobladder: the Studer pouch and the T-pouch. The latter includes an extraserosal tunneled afferent limb which prevents reflux from the pouch to the kidneys. The primary endpoint of the study is renal function and anatomy at 3 years following surgery, with secondary endpoints including early and late postoperative complications, renal infections and need for secondary procedures. To date we have randomized 462 patients over approximately 6 years, with a planned full enrollment of 550 patients. Ten percent of patients have been withdrawn because they did not undergo the planned orthotopic diversion due to a positive urethral margin on frozen section. We expect approximately 70% of patients to be alive and available for follow-up at 3 years, which will give us ample power to detect clinically meaningful differences in the outcome of these two diversions. This trial has been feasible and randomization has been acceptable to most patients. Long-term follow-up of the patients on this trial should be able to definitively answer the question of the importance of an antireflux mechanism in the orthotopic neobladders construction.
| 19,002,689
|
Carbon dioxide does not affect the methylation status of prognostic important oncogenes Rassf1A and DCR2 in neuroblastoma cells.
|
The aim of the current study was to investigate effects of CO(2) atmosphere, mimicking conditions of the pneumoperitoneum during laparoscopy, on epigenetic conditions of Rassf1A and DCR2 oncogenes in neuroblastoma cells. SH-SY5Y neuroblastoma cells were exposed to 100% CO(2) for 4 h. Cells were lysed 4, 8 and 168 h after exposure. After methylation analysis of Rassf1A and DCR2 with polymerase chain reaction, results were compared to those of physiologically incubated neuroblastoma cells. No significant changes were found after exposure to carbon dioxide compared to the control. Values of methylated Rassf1A were 12.6 +/- 1.1 versus 13.2 +/- 1.4 ng/microl in the controls, respectively (4 h after incubation), 12.6 +/- 1.2 versus 15.1 +/- 0.9 ng/microl (8 h) and 14.2 +/- 1.5 versus 11.7 +/- 1.3 ng/microl (168 h). DCR2 showed values of 4.6 +/- 0.5 versus 3.7 +/- 0.5 ng/microl (4 h), 3.8 +/- 0.5 versus 4.1 +/- 0.4 ng/microl (8 h) and 3.6 +/- 0.4 versus 3.8 +/- 0.5 ng/microl (168 h). Exposure of neuroblastoma cells to 100% CO(2) does not alter methylation of two prognostic relevant index genes. It seems therefore unlikely that effects on methylation levels within CO(2) pneumoperitoneum lead to epigenetic changes in neuroblastoma.
| 19,002,696
|
Spiral CT virtual bronchoscopy with multiplanar reformatting in the evaluation of post-intubation tracheal stenosis: comparison between endoscopic, radiological and surgical findings.
|
We evaluated the usefulness and accuracy of spiral CT in detection and assessment of post-intubation tracheal stenosis. Fourteen patients with post intubation stenosis underwent evaluation of their airway by spiral CT scan with multiplanar reformatting (MPR) and virtual endoscopy (VE) and conventional rigid bronchoscopy, and telescopy (RB). The following parameters were assessed: involvement of the subglottic larynx, site, number, and degree of the stenosis. The results were compared with the intra-operative findings. The detection rate for tracheal stenotic lesions was 94% by CT and 88% by rigid bronchoscopy. The sensitivity and specificity of both CT scan and bronchoscopy in the detection of subglottic stenosis was 100%. The preoperative assessment of the length of stenosis was accurate in 14 (87%) of the 16 stenotic segments detected by CT and in 11 (73%) of the 15 segments detected by bronchoscopy. The length of stenosis as assessed intra-operatively significantly correlated with the data obtained with CT scan (r = 0.98, p < 0.001) and RB (r = 0.94, p < 0.001). The grade of stenosis was correctly assessed by bronchoscopy in 13/15 lesions (86%). CT measurements correctly estimated 15/16 (93.75%) lesions and allowed accurate measurements of the stenotic segment as well as the proximal and distal airway segments. Spiral CT scan with MPR and VE may be considered as a substitute to direct endoscopic examination and the additional information on laryngeal function can be easily obtained during flexible nasolaryngoscopic examination of the awake patient. This policy can minimize patient morbidity and spare them an extra anaesthetic for evaluation.
| 19,002,699
|
The effect of 60-h sleep deprivation on cardiovascular regulation and body temperature.
|
This study examined cardiovascular regulation and body temperature (BT) during 60 h of sleep deprivation in 20 young healthy cadets. Heart rate variability was measured during an active orthostatic test (AOT). Measurements were performed each day in the morning and evening after 2, 14, 26, 38, 50 and 60 h of sleep deprivation. In AOT, in the sitting and standing positions, heart rate decreased (P < 0.001), while high frequency and low frequency power increased (P < 0.05-0.001) during sleep deprivation. Body temperature also decreased (P < 0.001), but no changes were detected in blood pressure. In conclusion, the accumulation of 60 h of sleep loss resulted in increased vagal outflow, as evidenced by decreased heart rate. In addition, BT decreased during sleep deprivation. Thus, sleep deprivation causes alterations in autonomic regulation of the heart, and in thermoregulation.
| 19,002,705
|
The evolution of pyrroline-5-carboxylate synthase in plants: a key enzyme in proline synthesis.
|
Many plants synthesize and accumulate proline in response to osmotic stress conditions. A central enzyme in the proline biosynthesis is the bifunctional enzyme Delta(1)-pyrroline-5-carboxylate synthase (P5CS) that includes two functional catalytic domains: the gamma-glutamyl kinase and the glutamic-gamma-semialdehyde dehydrogenase. This enzyme catalyzes the first two steps of the proline biosynthetic pathway and plays a central role in the regulation of this process in plants. To determine the evolutionary events that occurred in P5CS genes, partial sequences from four Neotropical trees were cloned and compared to those of other plant taxa. Molecular phylogenetic analysis indicated that P5CS duplication events have occurred several times following the emergence of flowering plants and at different frequencies throughout the evolution of monocots and dicots. Despite the high number of conserved residues in plant P5CS sequences, positive selection was observed at different regions of P5CS paralogous genes and also when dicots and monocots were contrasted.
| 19,002,717
|
Significance of hemolysis on extracorporeal life support after cardiac surgery in children.
|
Hemolysis is common during extracorporeal life support (ECLS). Elevated levels of circulating plasma free hemoglobin (FHb) has been linked to the development of hemoglobinuria nephropathy. Its clinical significance in patients receiving ECLS remains unknown. Medical records of 104 children <3 years old who required ECLS after repair of congenital heart disease were reviewed. Forty-two patients required continuous renal replacement therapy (CRRT) during ECLS (CRRT group), and 62 patients did not (no-CRRT group). For all patients, FHb level and the degree of fluid overload at the end of ECLS predicted the mortality rate during ECLS. Compared with the no-CRRT group, the CRRT group had a higher mortality rate during ECLS, a higher peak FHb level during ECLS, a higher FHb level at the end of ECLS, and more days of ECLS. In the CRRT group, the FHb level at the end of ECLS predicted death during ECLS. In the no-CRRT group, the peak FHb level was associated with a worse renal function. In conclusion, elevated FHb levels were associated with renal dysfunction and death during ECLS in children undergoing cardiac surgery. Further studies are needed to elucidate the cause-effect relationship in our findings.
| 19,002,722
|
Obesity surgery results depending on technique performed: long-term outcome.
|
Many techniques have excellent results at 2 years of follow-up but some matters regarding their long-term efficacy have arisen. This is why bariatric surgery results must be analyzed in long-term follow-up. The aim of this study was to extend the analysis over 5 years, evaluating weight loss, morbidity, and mortality of the surgical procedures performed. This was a retrospective cohort study of the different procedures for morbid obesity practiced in our Department of Surgery for morbid obesity. The results have been analyzed in terms of weight loss, morbidity improvement, and postoperative morbidity (Bariatric Analysis And Reporting Outcome System). One hundred twenty-five patients were operated on open vertical banded gastroplasty (VBG), 150 patients of open biliopancreatic diversion (BPD) of Scopinaro, 100 patients of open modified BPD (common limb 75 cm; alimentary limb 225 cm), and 115 patients of laparoscopic Roux-en-Y gastric bypass (LRYGBP). Mean follow-up was: VBG 12 years, BPD 7 years, and LRYGBP 4 years. An excellent initial weight loss was observed at the end of the second year of follow-up in all techniques, but from this time an important regain of weight was observed in VBG group and a discrete weight regain in LRYGBP group. Only BPD groups kept excellent weight results so far in time. Mortality was: VBG 1.6%, BPD 1.2%, and LRYGBP 0%. Early postoperative complications were: VBG 25%, BPD 20.4%, and LRYGBP 20%. Late postoperative morbidity was: protein malnutrition 11% in Scopinaro BPD, 3% in Modified BPD group, and no cases reported either in VBG group or LRYGBP group; iron deficiency 20% VBG, 62% Scopinaro BPD, 40% modified BPD, and 30.5% LRYGBP. A 14.5% of VBG group required revision surgery to gastric bypass or to BPD due to 100% weight regain or vomiting. A 3.2% of Scopinaro BPD with severe protein malnutrition required revision surgery to lengthen common limb to 100 cm. A 0.8% of LRYGBP required revision surgery to distal LRYGBP (common limb 75 cm) due to 100% weight regain. The most complex bariatric procedures increase the effectiveness but unfortunately they also increase morbidity and mortality. LRYGBP is safe and effective for the treatment of morbid obesity. Modified BPD (75-225 cm) can be considered for the treatment of superobesity (body mass index > 50 kg/m(2)), and restrictive procedures such as VBG should only be performed in well-selected patients due to high rates of failure in long-term follow-up.
| 19,002,740
|
Large-cell neuroendocrine carcinoma without immunohistological positivity or serum elevation of CEA until relapse.
|
We herein report a case of large cell neuroendocrine carcinoma (LCNEC) originating in the right lung upper lobe and showing unique features at relapse in the right middle lobe. The relapsed tumor pathology included a carcinoembryonic antigen (CEA)-positive mantle component and a CEA-negative core area. The latter showed the same pathological picture as the original tumor, both histologically and immunohistochemically. The serum CEA concentration did not increase until the tumor relapsed, and it fell to within the normal range after resection of the relapsed tumor. Rarely, a newly elevated tumor marker suggests relapse, even in resected cases with a negative immunohistochemical study for the marker.
| 19,002,754
|
Hydrogen production and anaerobic decolorization of wastewater containing Reactive Blue 4 by a bacterial consortium of Salmonella subterranea and Paenibacillus polymyxa.
|
Anaerobic biodegradability of wastewater (3,000 mg CODcr/l) containing 300 mg/l Reactive Blue 4, with different co-substrates, glucose, butyrate and propionate by a bacterial consortium of Salmonella subterranea and Paenibacillus polymyxa, concomitantly with hydrogen production was investigated at 35 degrees C. The accumulative hydrogen production at 3,067 mg CODcr/l was obtained after 7 days of incubation with glucose, sludge, the bacterial consortium. The volatile fatty acids, residual glucose and the total organic carbon were correlated to hydrogen obtained. Interestingly, the bacterial consortium possess decolorization ability showing approximately 24% dye removal after 24 h incubation using glucose as a co-substrate, which was about two and eight times those of butyrate (10%), propionate (12%) and control (3%), respectively. RB4 decolorization occurred through acidogenesis, as high volatile fatty acids but low methane was detected. The bacterial consortium will be the bacterial strains of interest for further decolorization and hydrogen production of industrial waste water.
| 19,002,762
|
Prognostic potential of precise molecular diagnosis of Autosomal Recessive Osteopetrosis with respect to the outcome of bone marrow transplantation.
|
Hematopoietic stem cell transplantation (HSCT) is often the only practical approach to fatal genetic defects. One of the first pathologies which HSCT was applied to was Autosomal Recessive Osteopetrosis (ARO), a rare genetic bone disease in which a deficit in bone resorption by osteoclasts leads to increased bone density and secondary defects. The disease is often lethal early in life unless treated with HSCT. In utero transplantation (IUT) of the oc/oc mouse, reproducing the clinical features of a subset of ARO, has demonstrated that the quality of life and the survival of transplanted animals are greatly improved, suggesting that a similar protocol could be applied to humans. However, recently the dissection of the molecular bases of the disease has shown that ARO is genetically heterogeneous and has revealed the presence of subsets of patients which do not benefit from HSCT. This observation highlights the importance of molecular diagnosing ARO to identify and establish the proper therapies for a better prognosis. In particular, on the basis of experimental results in murine models, efforts should be undertaken to develop approaches such as IUT and new pharmacological strategies.
| 19,002,772
|
Drug resistance and DNA repair in leukaemia.
|
Most cytotoxic agents exert their action via damage of DNA. Therefore, the repair of such lesions is of major importance for the sensitivity of malignant cells to chemotherapeutic agents. The underlying mechanisms of various DNA repair pathways have extensively been studied in yeast, bacteria and mammalian cells. Sensitive and drug resistant cancer cell lines have provided models for analysis of the contribution of DNA repair to chemosensitivity. However, the validity of results obtained by laboratory experiments with regard to the clinical situation is limited. In both acute and chronic leukaemias, the emergence of drug resistant cells is a major cause for treatment failure. Recently, assays have become available to measure cellular DNA repair capacity in clinical specimens at the single-cell level. Application of these assays to isolated lymphocytes from patients with chronic lymphatic leukaemia (CLL) revealed large interindividual differences in DNA repair rates. Accelerated O(6)-ethylguanine elimination from DNA and faster processing of repair-induced single-strand breaks were found in CLL lymphocytes from patients nonresponsive to chemotherapy with alkylating agents compared to untreated or treated sensitive patients. Moreover, modulators of DNA repair with different target mechanisms were identified which also influence the sensitivity of cancer cells to alkylating agents. In this article, we review the current knowledge about the contribution of DNA repair to drug resistance in human leukaemia.
| 19,002,791
|
Properties of ras-amplified recombinant BHK-21 cells in protein-free culture.
|
We compared serum and protein-free cultures ofa ras-amplified recombinant BHK-21 cell line(ras-rBHK-IgG), which hyperproduces a lungcancer specific recombinant human monoclonal antibody. Ras-rBHK-IgG cells were shown to grow well, evenin protein-free medium and to be morphologicallysimilar to cells cultured in serum containing medium. However, the growth rate of ras-rBHK-IgG cellswas considerably slower in protein-free medium, whichresults in a longer maintenance period compared with cells cultured in serum containing medium. In addition, it was found that antibody production in protein-free culture had a ten times higher maximum than cells cultured in serum containing medium. On theother hand, in high density culture, using the hollowfiber bioreactor system, ras-rBHK-IgG cellscould be maintained for a month in protein-freeculture in contrast with serum culture, which onlylasted for half a month. However, the markedincrease of antibody production was not observed. A total amount of about 15 mg of the recombinantantibody, obtained in protein-free culture, was abouttwo times of that obtained in serum culture, and wasshown to be reactive to lung cancer cells in tissue. From these properties in protein-free medium, it isconcluded that protein-free culture of ras-rBHK-IgG cells is suitable for middle scaleproduction of recombinant human monoclonal antibody.
| 19,002,807
|
Improvement of a method to reproducibly immortalize human T cells by oncogene transfection.
|
The method to immortalize human T cells efficiently and reproduciblyby oncogene transfection was improved. T cells were first grown selectively from peripheralblood lymphocytes population of healthy donors andatopic asthma patients, and from lymph nodelymphocytes population of lung cancer patients byactivating with mitogens (phytohemagglutinin andconcanavalin A) and recombinant human interleukin-2(rhIL-2) for five days. Plasmids expressingoncogenes, such as c-Ha-ras, c-myc,c-fos, v-myb and v-jun under the controlof human cytomegalovirus promoter, were then introducedinto these stimulated lymphocytes either separately orin various combinations by electropolation. Afterculturing these transfected lymphocytes for recoveryfor 1 day, they were fed every 3-4 days. Although all the control cells died within one month,oncogene-transfected lymphocytes continued toproliferate actively even for more than severalmonths, indicating that oncogene-transfectedlymphocytes were successfully immortalized. Flowcytometric analyses revealed that most of theimmortalized lymphocytes were T cells expressingCD3(+) surface antigen. The ratios of CD4(+)and CD8(+) subpopulations in immortalized T cellsderived from healthy donors varied, depending onthe kinds of oncogenes used. However, CD8(+)subpopulation in immortalized T cells derived fromcancer patients and atopic asthma patients weredominant, independent of the kinds of oncogenes. These immortalized T cells showed differentproliferative responses in the presence or absence ofexogenous human rhIL-2, depending on their origin ofdonors. Furthermore, immortalized T cells derivedfrom healthy donors showed stronger cytotoxicityagainst K562 cells, suggesting that MHC-nonrestrictedkiller T cells in T cell population were alsoimmortalized. Immortalized T cell lines, whichproliferate continuously without stimulation of amitogen or antigen in medium containing a lowconcentration of rhIL-2, have been maintained for morethan 2 years without any growth rate decrease.
| 19,002,813
|
Micropattern-immobilization of heparin to regulate cell growth with fibroblast growth factor.
|
Heparin was immobilized on a polystyrene plate in a specificpattern by photolithography. Heparin was coupled with azidoaniline. Thederivatized heparin was cast on the polystyrene plate from aqueoussolution. After drying, the plate was photo-irradiated in the presence of aphotomask. The micropatterning was confirmed by staining with a dye,ethydium bromide. Since heparin has negative charges, the cationic dyewas adsorbed on the regions where heparin was immobilized. In thepresence fibroblast growth factor (FGF), the growth of mouse fibroblastSTO cells was enhanced only on the heparin-immobilized regions. Thisresult indicated that micropattern-immobilized heparin activated FGF forcell growth activity.
| 19,002,818
|
Treatment of mouse melanoma cells with phorbol 12-myristate 13-acetate counteracts mannosylerythritol lipid-induced growth arrest and apoptosis.
|
Mannosylerythritol lipid (MEL), an extracellularglycolipid from yeast, induces the differentiation ofHL-60 promyelocytic leukemia cells towardsgranulocytes. We show here that MEL is also a potentinhibitor of the proliferation of mouse melanoma B16cells. Flow-cytometric analysis of the cell cycle ofMEL-treated B16 cells revealed the accumulation ofcells in the sub-G(0)/G(1) phase, which is a hallmark ofcells undergoing apoptosis. Treatment of B16 cellsfor 24 h with phorbol 12-myristate 13-acetate (PMA),an activator of protein kinase C (PKC), did notinterfere with the growth and survival of the cells,but it effectively counteracted the MEL-induced growtharrest and apoptosis. The activity of PKC was reducedin B16 cells treated with MEL at a concentration atwhich MEL induced apoptosis. However, incubation withPMA in addition to MEL reversed this reduction in theactivity of PKC. These results suggest thatconverging signaling pathways are triggeredindependently by MEL and PMA and that the signalsmight both be mediated by PKC.
| 19,002,819
|
Glutamate triggers elevation of intracellular Ca(2+) concentration in neural precursor cells.
|
Both neurons and glial cells are derived from neuralprecursor cells in the ventricular zone during braindevelopment. The fate of the neural precursor cells isaffected by neurotransmitters such as glutamate. Inthis study, we examined glutamate-triggeredintracellular Ca(2+) signaling in neural precursorcell lines by the calcium digital imaging method. Whenimmortalized primary-cultured neural precursor cellswere treated with glutamate, a subpopulation of thesecells showed an increase in intracellular Ca(2+)concentration. In an effort to determine the role ofthe glutamate-triggered intracellular Ca(2+) signalin neural precursor cells, we tried to cultureimmortalized basal ganglial and hippocampal neuralprecursor cell lines in glutamate-free medium. Thehippocampal (MHP-2) cells became adapted to theglutamate-free medium, and when treated with glutamatethe adapted subline (MHP-2-E1) showed an increase inintracellular Ca(2+) concentration. In contrast,the basal ganglial neural precursor cell lines failedto become adapted to the glutamate-free medium. Theseresults suggest that hippocampal and basal ganglialneural precursor cells differ in their cellularresponse to glutamate as an exogenous stimulus.
| 19,002,823
|
Separation of CHO cells using hydrocyclones.
|
Hydrocyclones are simple and robust separation devices with no moving parts. In the past few years, their use in animal cell separation has been proposed. In this work, the use of different hydrocyclone configurations for Chinese hamster ovary (CHO) cell separation was investigated following an experimental design. It was shown that cell separation efficiencies for cultures of the wild-type CHO.K1 cell line and of a recombinant CHO cell line producing granulocyte-macrophage colony stimulating factor (GM-CSF) were kept above 97%. Low viability losses were observed, as measured by trypan blue exclusion and by determination of intracellular lactate dehydrogenase (LDH) released to the culture medium. Mathematical models were proposed to predict the flow rate, flow ratio and separation efficiency as a function of hydrocyclone geometry and pressure drop. When cells were monitored for any induction of apoptosis upon passage through the hydrocyclones, no increase in apoptotic cell concentration was observed within 48 h of hydrocycloning. Thus, based on the high separation efficiencies, the robustness of the equipment, and the absence of apoptosis induction, hydrocyclones seem to be specially suited for use as cell retention devices in long-term perfusion runs.
| 19,002,842
|
The effects of boric acid on sister chromatid exchanges and chromosome aberrations in cultured human lymphocytes.
|
The aim of this study was to determine the possible genotoxic effects of boric acid (BA) (E284), which is used as an antimicrobial agent in food, by using sister chromatid exchange (SCEs) and chromosome aberration (CAs) tests in human peripheral lymphocytes. The human lymphocytes were treated with 400, 600, 800, and 1000 mug/mL concentrations of BA dissolved in dimethyl sulfoxide (DMSO), for 24 h and 48 h treatment periods. BA did not increase the SCEs for all the concentrations and treatment periods when compared to control and solvent control (DMSO). BA induced structural and total CAs at all the tested concentrations for 24 and 48 h treatment periods. The induction of the total CAs was dose dependent for the 24 h treatment period. However, BA did not cause numerical CAs. BA showed a cytotoxic effect by decreasing the replication index (RI) and mitotic index (MI). BA decreased the MI in a dose-dependent manner for the 24 h treatment period.
| 19,002,846
|
Small interfering RNA knockdown of mini-TyrRS and mini-TrpRS effects angiogenesis in human umbilical vein endothelial cells in hypoxic culture.
|
Aim We studied the role of mini-TyrRS and mini-TrpRS in angiogenesis by using small interfering RNA-mediated mini-TyrRS/mini-TrpRS knockout in hypoxic culture of human umbilical vein endothelial cells. Methods SiRNA was used as the main method to inhibited the gene function. Silencing efficiency was assayed by real-time reverse transcription-polymerase chain reaction and western blotting. The angiogenic activity in vitro was evaluated by transwell migration assay and Matrigel-induced capillary tube formation in hypoxic culture. Cell proliferation was determined by crystal violet staining. Results The results showed that levels of the mini-TyrRS/mini-TrpRS gene and protein in mock transfection group and negative control group were higher, but noticeably decreased in experimental group. However, no significant difference was detected between mock transfection group and negative control group, but there was a statistically significant difference compared with experimental group. For mini-TyrRS-siRNA group, the cell migration, tube formation and the rate of cell proliferation were respectively inhibited by (47.4, 56.3, 65.4, 73.7%), (60.5, 69.1, 75.9, 83.6%) and (40.4, 56.2, 61.2, 68.0%). For mini-TrpRS-siRNA, were respectively increased by (18.0, 33.8, 45.1, 56.4%), (18.3, 31.2, 40.3, 45.7%) and (8.4, 26.4, 38.2, 46.6%). Conclusion These results indicated that angiogenesis is either stimulated by mini-TyrRS or inhibited by mini-TrpRS in matrigel models in hypoxic culture, raising the possibility that mini-TyrRS stimulates a common downstream signaling event. Thus, naturally occurring fragments of two proteins involved in translation, TyrRS and TrpRS, have opposing activity on endothelial cell angiogenesis in the matrigel assays. The opposing activities of the two tRNA synthetases suggest tight regulation of the balance between pro- and anti-angiogenic stimuli.
| 19,002,860
|
Related effects of cell adaptation to serum-free conditions on murine EPO production and glycosylation by CHO cells.
|
The necessity to perform serum-free cultures to produce recombinant glycoproteins generally requires an adaptation procedure of the cell line to new environmental conditions, which may therefore induce quantitative and qualitative effects on the product, particularly on its glycosylation. In previous studies, desialylation of EPO produced by CHO cells was shown to be dependent on the presence of serum in the medium. In this paper, to discriminate between the effects of the adaptation procedure to serum-free medium and the effects of the absence of serum on EPO production and glycosylation, adapted and non-adapted CHO cells were grown in serum-free and serum-containing media. The main kinetics of CHO cells were determined over batch processes as well as the glycosylation patterns of produced EPO by HPCE-LIF. A reversible decrease in EPO production was observed when cells were adapted to SFX-CHO(TM) medium, as the same cells partially recovered their production capacity when cultivated in serum-containing medium or in the enriched SFM(TM) serum-free medium. More interestingly, EPO desialylation that was not observed in both serum-free media was restored if the serum-independent cells were recultured in presence of serum. In the same way, while the serum-independent cells did not release a sialidase activity in both serum-free media, a significant activity was recovered when serum was added. In fact, the cell adaptation process to serum-free conditions did not specifically affect the sialidase release and the cellular mechanism of protein desialylation, which appeared to be mainly related to the presence of serum for both adapted and non-adapted cells.
| 19,002,864
|
Influence of medium type and serum on MTT reduction by flavonoids in the absence of cells.
|
The MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay is widely accepted as a simple and reproducible method for determining cell proliferation or cytotoxicity in vitro. In this study, we show that the flavonoids quercetin, rutin and luteolin but not apigenin can reduce MTT in the absence of live cells in the following order: quercetin >> rutin > luteolin > apigenin. Moreover, this reduction can be influenced by medium type and serum. The final concentrations of the flavonoids used were 200, 100, 50, 25 and 12.5 mug/mL. MTT reduction in Dulbecco's Modified Eagle's Medium (DMEM) is statistically higher than those in RPMI 1640 and F12 media, which are generally similar. Particularly for luteolin, MTT reduction is considerably higher with serum than without serum. In the case of quercetin at 50 mug/mL, a serum concentration of even only 0.01% is sufficient to significantly enhance MTT reduction versus that at 0% (P < 0.05). Serum at concentrations ranging from 0% to 5% also dose-dependently affects the pattern of formazan crystal formation. In the presence of 0.156-5% serum, the formazan crystals gradually change from being small, numerous and scattered to being large, few and clumpy. The authors hypothesize that flavonoid structure, nutrient concentration in the culture medium as well as serum components directly affect MTT reduction by flavonoids in the absence of cells.
| 19,002,877
|
In vitro immunization can elicit the expansion of diverse repertoire of B cells from peripheral blood mononuclear cells.
|
We previously developed an in vitro immunization (IVI) protocol of human peripheral blood mononuclear cells (PBMC) for generating antigen-specific human antibodies. In order to clarify whether IVI protocolinduces antigen-specific B cell responses in PBMC, we analyzed family gene usage and sequence of the variable region gene of immunoglobulin heavy chain (VH gene) of the antibody produced from the in vitro immunized PBMC. Sequence homology analyses of VH gene demonstrated that a larger repertoire of B cells can be sensitized with mite-extract than with cholera toxin B subunit and rice allergen. Further, antigen-specific B cells were efficiently expanded by using CpG oligodeoxynucleotide as adjuvant. These results suggest that appropriate combination of sensitizing antigen and adjuvant is primarily important for expansion of antigen-specific B cells in IVI protocol.
| 19,002,881
|
Culture of bovine hepatocytes: a non-perfusion technique for cell isolation.
|
In this work we have studied the isolation and culture of mature bovine hepatocytes on plastic dishes without exogenous matrix. The liver has been disaggregated in a collagenase solution instead of undergoing a perfusion step. After a few days in culture, the plates showed several clusters of different cell types. Although the average yield was 1.60+/-0.57x10(8) viable liver cells per gram of tissue, these cultures were formed by non-parenchymal cells and only very few or none by parenchymal cells. In these cultures, actin structures used as a marker for Stellate (Ito) cells have been visualized by immunocytochemical techniques. In order to increase the proportion of parenchymal cells a centrifugation on Percoll, which separates cell sub-populations, has been introduced. Though the yield was lower than in the previous method, these pre-purified cultures were only composed of hepatocytes. It has been shown that these cells exhibited albumin synthesis, which is a specific hepatocytes function. In addition, these cultures were capable of producing metabolites of 7-ethoxycoumarin at a higher rate than non purified cell cultures. Therefore this simplified procedure for the isolation and culture of functional and viable hepatocytes may be applied for in vitro studies in bovine.
| 19,002,895
|
Caspase activation, sialidase release and changes in sialylation pattern of recombinant human erythropoietin produced by CHO cells in batch and fed-batch cultures.
|
The activation of caspases represents a crucial turning point during a batch or a fed-batch culture of mammalian cells. It not only affects the quantity but also the quality of the recombinant glycoprotein produced. In this study, the activation of various caspases, the release of intracellular sialidase and the changes in sialylation pattern of a recombinant product, erythropoietin (EPO), in the culture medium were analyzed in both batch and fed-batch cultures. In both setups, all caspase activities peaked at the culture time point at which decline of cell viability was most pronounced. In addition, the release of intracellular lactate dehydrogenase (LDH) was also tracked during these cultures. The increase in LDH activity in the medium coincided with the increase of intracellular caspase activities, the release of sialidase and the observed decline in cell viability, suggesting that the LDH activity in the medium can be used as an indirect indicator of apoptotic cell death in bioreactors. Isoelectric focusing (IEF) coupled with double blotting was employed to analyze the changes in sialylation pattern of the recombinant EPO. This assay resulted in a prompt resolution of secreted EPO isoforms in a time course format. IEF profile of batch culture showed relatively consistent product sialylation compared to fed-batch culture, which showed gradual band shifts towards the isoforms with fewer sialic acid as the culture progressed. These data provided a guideline for the optimal time point to terminate the culture and collect products in batch and fed-batch cultures.
| 19,002,897
|
Pooling and PCR as a method to combat low frequency gene targeting in mouse embryonic stem cells.
|
The introduction of germ line modifications by gene targeting in mouse embryonic stem (ES) cells has proven a fundamental technology to relate genes to mammalian biology. Critical aspects required for successful gene targeting have traditionally been experimental enhancements that increase the frequency or detection of homologous recombination within ES cells; however, the utilization of such methods may still result in the failed isolation of a positively targeted ES cell clone. In this study, we discuss the current enhancement methods and describe an ES cell pooling strategy that maximizes the ability to detect properly targeted ES cells regardless of an inherent low targeting efficiency. The sensitivity required to detect correctly targeted events out of a pool of ES cell clones is provided by polymerase chain reaction (PCR), and only those pools containing positives need to be expanded and screened to find individually targeted clones. This method made it possible to identify targeted clones from a screen of approximately 2,300 ES cell colonies by performing only 123 PCR reactions. This technically streamlined approach bypasses the need to troubleshoot and re-engineer an existing targeting construct that is functionally suitable despite its low targeting frequency.
| 19,002,898
|
Amino acids metabolism by VO 208 hybridoma cells: some aspects of the culture process and medium composition influence.
|
In the present study an approach has been developed in order to examine the consequence of essential and non essential amino acid supplementation on VO208 hybridoma cells behaviour. The effect of amino acid enrichment has been studied taking into account the culture process, i.e., batch or continuous culture mode and the medium composition, i.e., a home made serum-free medium or a serum containing one. A group of 4 amino acids, i.e., Ser, Pro, Gly and Arg presented atypical evolution pattern of their extracellular concentration depending on the type of the medium and on the culture mode. Some amino acids were probably involved in the limitation of the cellular proliferation. Met was one of the amino acids that appears to may have been at limiting concentration in all cases. In continuous culture mode, an enrichment of amino acids resulted in a rapid improvement of the viable cell density in both media, with or without the presence of serum. For most amino acids, supplementation during continuous culture induced an increase of the amino acid uptake rate. A comparative analysis of amino acids utilisation, depending on the culture conditions studied in the present study, has been performed in order to propose an overall picture of amino acids metabolism by VO 208 Hybridoma cell line.
| 19,002,906
|
Stable expression of recombinant human coagulation factor XIII in protein-free suspension culture of Chinese hamster ovary cells.
|
The recombinant a and bsubunits for human coagulation factor XIII were transfected into Chinese hamster ovary (CHO) cells. CHO cells were amplified and selected with methotrexate in adherent cultures containing serum, and CHO 1-62 cells were later selected in protein-free medium. To develop a recombinant factor XIII production process in a suspension culture, we have investigated the growth characteristics of CHO cells and the maintenance of factor XIII expression in the culture medium. Suspension adaptation of CHO cells was performed in protein-free medium, GC-CHO-PI, by two methods, such as serum weaning and direct switching from serum containing media to protein-free media. Although the growth of CHO cells in suspension culture was affected initially by serum depletion, cell specific productivity of factor XIII showed only minor changes by the direct switching to protein-free medium during a suspension culture. As for the long-term stability of factor XIII, CHO 1-62 cells showed a stable expression of factor XIII in protein-free condition for 1000 h. These results indicate that the CHO 1-62cells can be adapted to express recombinant human factor XIII in a stable maimer in suspension culture using a protein-free medium. Our results demonstrate that enhanced cell growth in a continuous manner is achievable for factor XIII production in a protein-free medium when a perfusion bioreactor culture system with a spin filter is employed.
| 19,002,921
|
Production of interferon-beta by NB1-RGB cells cultured on peptide-lipid membranes.
|
Cell growth and production of interferon-beta (IFN-beta) were investigated for normal human skin fibroblast cells (NB1-RGB) cultured on membranes prepared from peptide-lipids containing the arginine-glycine-aspartic acid [Arg-Gly-Asp] (RGD), tyrosine-isoleucine-glycine-serine-arginine [Tyr-Ile-Gly-Ser-Arg] (YIGSR) and arginine-glutamic acid-aspartic acid-valine [Arg-Glu-Asp-Val] (REDV) peptides. Cell density was found to be approximately the same on various peptide-lipid membranes, whereas production of IFN-beta depended significantly on the peptide-lipid membranes on which NB1-RGB cells were cultured. The highest production of IFN-beta was observed for NB1-RGB cells on REDV-lipid membranes prepared by a casting method (REDV-cast membranes) after 24 hr of cultivation. Specific binding between REDV of REDV-cast membranes and the receptor on the NB1-RGB cells may have caused the specific cell response for the production of IFN-beta.
| 19,002,924
|
SEAP expression in transiently transfected mammalian cells grown in serum-free suspension culture.
|
A transient transfection process was established using a novel 'in-house' developed transfection reagent, Ro-1539. It allows rapid production of large quantities of various recombinant proteins. Here we describe the transient expression of the secreted human placental alkaline phosphatase (SEAP) by HEK293EBNA and CHO cells in serum-free suspension culture. Unexpectedly, high expression levels of SEAP (150 mug/ml) were found 3-4 days post-transfection when placental alkaline phosphatase (AP) was used as the reference enzyme. To confirm these data, an SDS-PAGE analysis was performed and the visible SEAP protein band (MW of 65 kDa) was compared with co-migrated purified placental AP protein as reference. The scanning analysis of the gel showed that SEAP, a truncated form of AP, has a higher specific activity than the purified placental AP. A correction factor was introduced permitting a direct comparison of placental AP activity with the expression levels of SEAP. Scale-up of the transfection system from spinner flask to bioreactor was simple and straightforward, resulting in similar yields of SEAP. Finally, the effectiveness of Ro-1539 was compared to that of other transfection reagents.
| 19,002,927
|
Development of a standardized protocol for reproducible generation of matured monocyte-derived dendritic cells suitable for clinical application.
|
There is increasing interest in the generation of dendritic cells (DC) for cancer immunotherapy. In order to utilize DC in clinical trials it is necessary to have standardized, reproducible and easy to use protocols. We describe here the process development for the generation of DC as the result of investigation of culture conditions as well as consumption rates of medium and cytokines. Our studies demonstrate that highly viable DC (93 +/- 2%) can be produced from CD14(+) enriched monocytes via immunomagnetic beads in a high yield (31 +/- 6%) with X-VIVO 15, 400 U ml(-1) GM-CSF and 2000 U ml(-1) IL-4 without serum and feeding. For the maturation of DC different cocktails (TNF-alpha, IL-1beta, IL-6, PGE(2) and TNF-alpha, PGE(2)) were compared. In both cases cells expressed typical surface molecules of mature DC and induced high proliferative responses in mixed lymphocyte reactions which led to IFN-gamma producing T-lymphocytes. The data suggest that the use of this optimized, easy to use protocol results in highly mature DC.
| 19,002,934
|
Use of hollow fiber systems for rapid and direct scale up of antibody production from hybridoma cell lines cultured in CL-1000 flasks using BD Cell MAb medium.
|
The combination of BD Cell MAb medium with the CL-1000 flask is increasingly being used to generate a few hundred milligram of antibody for early stage research projects. Cells are inoculated at 2 million per ml, and the antibody is harvested after 15 days or when the antibody concentration reaches above 10 mg ml(-1), whichever comes first. Currently, there is no means to scale up beyond this production level using this technology. In this study, we evaluated hollow fiber technology as the scale up alternative. The hollow fiber system was run in batch mode to mimic the method used for the CL-1000 with BD MAb medium. The FL-NS murine hybridoma cell line was simultaneously inoculated at 2 million cells per ml in a CL-1000 and the Maximizer hollow fiber bioreactor system, a 21-fold theoretical scale up over the CL-1000. The Maximizer produced 23-fold more antibody, very close to the expected theoretical amount. However, production was complete after 9 days in the Maximizer, while the CL-1000 required the full 15 days for production. In summary, these results demonstrate successful scale up of antibody production from the CL-1000 to a hollow fiber system.
| 19,002,937
|
Estimating the number of viable animal cells in multi-well cultures based on their lactate dehydrogenase activities.
|
A method is described for estimating the numbers ofanimal cells in multi-well culture by simultaneouslymeasuring the lactate dehydrogenase activity of thetotal culture and the medium. The difference betweenthe two reflects the dehydrogenase content of thecells and correlates with cell number. This LDH/INTmethod was tested using several lines of normal andtransformed suspension and adherent cells. Thelactate dehydrogenase activities of duplicate cultureswere determined colourimetrically using reactioncocktails containing lactate, NAD(+), diaphorase,and p-iodonitrotetrazolium violet, with and withoutTriton X-100. The difference in absorbance at 490 nm(DeltaA(490) = A(490, test) - A(490, control)) was used to calculate the lactatedehydrogenase activity of the total culture (+ Triton)and the medium (- Triton). The cellular lactatedehydrogenase activity (difference between totaland medium dehydrogenaseactivities) was proportional to viable cell number. The effects on cell growth of four metabolicinhibitors, sodium azide, actinomycin D,cycloheximide, and taxol, were determined using theLDH/INT assay and direct cell counting. The inhibitorconcentrations that caused decreases in the LDHactivity and cell number by 50% were similar. TheLDH/INT assay is quick and sensitive, works equallywell for adherent and suspension cells, and providesinformation about LDH activities of both the mediumand cells. It is particularly useful for screeningpotential cell-growth inhibitors.
| 19,002,967
|
Matrigel increases the rate of split wound healing and promotes keratinocyte ;take' in deep wounds in rats.
|
The influence of matrigel, a mixture of the components of thebasement membrane, on the wound healing was studied in a modelof experimental wounds in rats. Matrigel was found to increasethe rate of epithelization of split-thickness wounds. The modelof deep wound was developed in which the host animal could notprovide enough migrating and proliferating keratinocytes tocover the wound area. The model is relevant to severe burns andinjuries in humans. When rat keratinocyte suspension wastransplanted into deep wounds, cell retention in the wound bedwas only observed if matrigel was added together with the cells.Increasing matrigel concentration in the wound was seen toenhance the rate of wound area coverage by the cells. Althoughthe process of healing seemed macroscopically normal, afterhistological screening of the biopsies cell in the wouldappeared as amorphous aggregates and tubules rather thenstratified epidermis.
| 19,002,969
|
Manipulation of cells through elastic films.
|
Manipulation of cells in open dishes is often incompatible withpreservation of sterility. A dish covered with an elastic orstretchable latex or plastic film allows manipulation of cellsthrough the film with preservation of sterility of the cultureand the integrity of the film. The latter forms a ;microglove'for the instrument tip. The idea of manipulation through a thintransparent film is also applicable to general surgery, so thatthe surgeon's hand operates through a film and without a glove.
| 19,002,987
|
Manufacture of a human mesenchymal stem cell population using an automated cell culture platform.
|
Tissue engineering and regenerative medicine are rapidly developing fields that use cells or cell-based constructs as therapeutic products for a wide range of clinical applications. Efforts to commercialise these therapies are driving a need for capable, scaleable, manufacturing technologies to ensure therapies are able to meet regulatory requirements and are economically viable at industrial scale production. We report the first automated expansion of a human bone marrow derived mesenchymal stem cell population (hMSCs) using a fully automated cell culture platform. Differences in cell population growth profile, attributed to key methodological differences, were observed between the automated protocol and a benchmark manual protocol. However, qualitatively similar cell output, assessed by cell morphology and the expression of typical hMSC markers, was obtained from both systems. Furthermore, the critical importance of minor process variation, e.g. the effect of cell seeding density on characteristics such as population growth kinetics and cell phenotype, was observed irrespective of protocol type. This work highlights the importance of careful process design in therapeutic cell manufacture and demonstrates the potential of automated culture for future optimisation and scale up studies required for the translation of regenerative medicine products from the laboratory to the clinic.
| 19,002,992
|
Recent advances in the generation of human monoclonal antibody.
|
The use of monoclonal antibodies (mAbs) has now gained a niche as an epochal breakthrough in medicine. Engineered antibodies (Abs) currently account for over 30% of biopharmaceuticals in clinical trials. Several methods to generate human mAbs have evolved, such as (1) immortalization of antigen-specific human B cell hybridoma technology, (2) generation of chimeric and humanized antibody (Ab) from mouse Ab by genetic engineering, (3) acquisition of antigen-specific human B cells by the phage display method, and (4) development of transgenic mice for producing human mAbs. Besides these technologies, we have independently developed a method to generate human mAbs by combining the method of in vitro immunization using peripheral blood mononuclear cells and the phage display method. In this paper, we review the developments in these technologies for generating human mAbs.
| 19,002,994
|
Effect of the water extracts of propolis on stimulation and inhibition of different cells.
|
The water extracts of propolis (WEP) could inhibit growth of different cell lines namely McCoy, HeLa, SP2/0, HEp-2, and BHK21 and stimulate growth of normal cell named human lymphocyte, rat kidney, rat liver, and rat spleen. In these experiments 1 and 2 mg of WEP were added to 1 ml RPMI media with 5% FCS. Cell counts and cell viability of propolis-treated and propolis-free cells were assessed by Trypan blue dye exclusion test and MTT assay. The results showed that in case of McCoy, HeLa, SP20, HEp-2, and BHK21 cell lines, the water extracts of propolis could inhibit cell growth as well as reduction on size of the cells. In contrast the same amount of WEP could stimulate growth of normal cells up to 60% with the same concentration used for cell lines. Thus our study indicates that although WEP consists only of the soluble part of propolis, it enables to inhibit different cell lines and increase growth of normal cells. This indicates also that WEP contains the specific compounds with bioactivity against cell lines. Although propolis contain different number of compounds it is clear that WEP has enough biological compounds useful for the treatment of some diseases, medical and related applications.
| 19,003,017
|
Isolation of progenitor cells from cord blood using adhesion matrices.
|
The aim of this study was to develop optimal conditions for selective adhesion and isolation of mesenchymal progenitor cells (MPCs) from cord blood and to determine their potential for osteogenic differentiation. Mononuclear cells (MNCs) were isolated by Ficoll-Paque gradient and plated onto 48-well culture plates precoated with: human or bovine collagen type I, human collagen type IV, fibronectin or matrigel. Cultures were incubated in alphaMEM containing fetal calf serum. Viability of the adherent cells was determined by alamarBlue(R) assay after 2, 3, and 4 weeks. After 4 weeks in culture, cells were typsinized and replated. Primary cultures were analyzed by histochemistry and third passage cells by FACS. Isolated fibroblast-like cells were cultured in the presence of osteogenic factors and differentiation determined by Alizarin Red S staining, RT-PCR and electron dispersive spectroscopy (EDS). MNCs adhered to all types of matrices with the greatest adhesion rates on fibronectin. These cells were CD45(+), CD105(+), CD14(+), CD49a(+), CD49f(+), CD44(+) and CD34(-). The highest incidence of progenitor cells (PC) was observed on fibronectin and polystyrene. Passages were CD45(-), CD14(-), CD34(-) and weakly CD105(+). Primary cultures expressed endothelial/macrophage RNA markers whether cultured on fibronectin or polystyrene and these markers decreased upon passage. The best osteogenic differentiation was observed in MPCs cultured in osteogenic medium containing vitamin D(3) and FGF9. These cells expressed the bone-related mRNA, collagen type I, core binding factor I (Cbfa I), osteocalcin and osteopontin. EDS of deposits produced by these cells demonstrated a calcium/phosphate ratio parallel to hydroxyapatite. It was concluded that fibronectin increased adhesion rates and isolation potential of cord blood mesenchymal progenitor cells.
| 19,003,027
|
Analysis of Methylglyoxal Metabolism in CHO Cells Grown in Culture.
|
Recent evidence suggests that several unknown or ill-characterized factors strongly influence cell growth and function in culture. Isolating these factors is necessary in order to maximize culture productivities. Methylglyoxal (MG), a potent protein and nucleic acid modifying agent, has been identified as a player in the signaling pathways associated with cell death and is known to be detrimental to cultured cells. This compound is produced in all mammalian systems by spontaneous phosphate elimination from glycolytic pathway intermediates. A kinetic model that qualitatively describes the cellular distribution of protein-associated MG in the absence of enzymatic adduct formation predicted far lower levels of reversibly bound MG than measured in cultured CHO cells. This suggests that the targeted modification of proteins through enzymatically mediated mechanisms is a significant sink for cellular methylglyoxal. The model was validated with measurements of carbon flux through the glyoxalase pathway to d-lactic acid, a unique end product of MG metabolism in mammalian systems. Fluxes to d-lactic acid of up to 16.8 mmol ml-packed cells(-1) day(-1) were measured with CHO cells grown in batch culture or 100-fold more than found in normal tissues.
| 19,003,028
|
Optimizing conditions for rat pancreatic islets isolation.
|
Many procedures have been described for rat pancreatic islet isolation. Several factors contribute to the pancreatic islet isolation outcome. One of the main problems in islet isolation procedure is the formation of a viscouse, gellike structure during collagenase digestion which entraps the free islets and decrease islet yield after density gradient purification. This issue has not been addressed in most techniques described for rat islet isolation. We examined effect of various factors to eliminate formation of gellike material and improve the islets yields. Islet isolation was performed on 26 adult male Wistar Albino rats weighing between 280 and 350 g. We have observed that several factors affect pancreatic islet isolation. Optimum Collagenase enzyme concentration, maintaining pH range between 7.7 and 7.9 in digestion solution, incubation temperature at 38+/-1 degrees C and addition of Calcium ion decreased the formation of gellike materials and increased islet yield. Addition of Glycerol as a gelatin solvent has also been helpful in the reduction or complete elimination of gellike material. Precise optimization of rat islet isolation procedure is useful to improve the islet yield in islet transplantation studies.
| 19,003,033
|
An Inexpensive Method for Applying Nitrogen Evaporation to Hexane-containing 24- or 96-well Plates.
|
A method is described for assembling an evaporation manifold from a cell culture flask, which allows for efficient nitrogen evaporation of hexane from 24- and 96-well plates. The precursor parts are readily available in most research laboratories. The nitrogen evaporation manifold is inexpensive, could possibly be used with other organic solvents, and appears ideal for a small number of samples in a multi-well format.
| 19,003,065
|
Oral administration of milk fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 to DBA/1 mice inhibits secretion of proinflammatory cytokines.
|
We have previously shown that oral administration of skimmed milk(SM) fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 (OLL1073R-1/SM) to DBA/1 mice inhibited the development of collagen-induced arthritis (CIA). In this study, our aim was to examine possible mechanisms of inhibiting the development of CIA. We studied the effect of OLL1073R-1/SM on cytokine secretion from cells of popliteal lymph nodes (lymph node cells; LNC) of mice. The results showed that feeding OLL1073R-1/SM inhibited secretion of proinflammatory cytokines such as interferon gamma (IFN-gamma), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha) and the chemokine, monocyte chemoattractant protein 1 (MCP-1). The most prominent effect was inhibition of TNF-alpha. Secretion of IL-2 and IL-4 were not influenced. Feeding OLL1073R-1/SM inhibited secretion of proinflammatory cytokines produced by accessory cells, but not T cells. We conclude that CIA may be prevented via down regulation of secretion of proinflammatory cytokines such as IL-6, TNF-alpha and IFN-gamma, and of the chemokine of MCP-1.
| 19,003,106
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.