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Selected AbstractsGene expression in distal intestine of Atlantic salmon (Salmo salar L.) fed genetically modified soybean mealAQUACULTURE NUTRITION, Issue 3 2008M.K. FRØYSTAD Abstract Limited availability of fishmeal leads to exploration of alternative protein sources like soybean meal (SBM). During the last decade, genetically modified (GM) plants have been introduced to the production of soybean crops. In the current experiment RNA was isolated from the distal intestinal section of Atlantic salmon fed either GM SBM or its near-isogenic parental line (non-GM), both at 30% inclusion. From a suppression subtractive hybridization cDNA library, 95 clones were sequenced. Clones with similarity to both known Atlantic salmon genes and novel Atlantic salmon sequences were identified. Real-time polymerase chain reaction was used to study differential expression of seven clones between the dietary groups. The clones were selected based on their relevance to intestinal immune responses and nutrient metabolism. Expression of a serum lectin-like clone was down-regulated in the GM group compared with the non-GM group. No differential expression was observed for six other clones with similarity to actin-related protein 2/3 complex-subunit 3, cysteine-rich intestinal protein, fatty acid binding protein/gastrotropin, ferritin heavy subunit, anterior gradient protein and peptide transporter. In conclusion, only minor differences in distal intestine transcriptional gene expression were observed between fish fed the diets with the non-GM and GM varieties. [source] An exploration into the wellbeing of the families living in the ,suburbs in the bush',AUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 3 2009Sanjay Sharma Abstract Objective: To examine the wellbeing of families of male mine-workers living in remote mining towns in Australia. Methods: Through an extensive review of available (but limited) social science literature on mining towns this paper explores and identifies the key social issues and problems of mining towns. Social science and health-related research are used to argue that there are several factors that may negatively affect the relationship and psychological wellbeing of family members. Results: Atypical work schedules of the mining jobs could negatively affect the long-term health of the workers, and could constrain their qualitative participation in domestic roles. Limited availability of resources, services and flexi-time jobs in mining towns marginalise female partners to domestic chores. Higher level of alcohol consumption by workers and their preferred spending of leisure time with workmates symbolise patriarchal culture in mining towns that further marginalises women and could strain marital relationships. These factors could affect the social and emotional health of the children. Conclusion: Interdisciplinary studies are needed to gain realistic understanding of the dynamics of long-term impacts of long work hours/compressed work weeks, socio-cultural, motivational and environmental factors on the wellbeing of the workers and their families living in mining towns. Family counsellors and mental health professionals working in remote mining towns must take into consideration the likely negative impacts of work and community on individuals and families. [source] Benzodiazepine prescribing in elderly Australian general practice patientsAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2007Alice Windle Abstract Objective: The use of benzodiazepines by elderly people is of limited therapeutic benefit and increases the risk of adverse events. This study aimed to examine the extent to which benzodiazepines are prescribed for elderly Australians. Methods: Data for 3,970 individuals aged 65 years or more were extracted from a general practice database. Benzodiazepine prescriptions for 2002 were reviewed. Results: Overall, 16% (95% CI 11,21%) of elderly patients had at least one benzodiazepine prescription. Females were almost twice as likely as males to be prescribed a benzodiazepine and prescription prevalence increased with age. Conclusions: Despite risks, benzodiazepines are widely prescribed for the elderly. Limited availability and cost of alternative therapies and pressures on the primary care system in Australia may contribute to their continued overuse. Implications: The prescribing of benzodiazepines for elderly Australians needs to be reduced by better managing sleep and anxiety problems. [source] A case of near-drowning: a case for routine cerebral monitoringACTA PAEDIATRICA, Issue 3 2010V Ponnusamy Abstract A 6-week-old infant presenting with near-drowning was medically paralysed and ventilated on admission. Status epilepticus was found on cerebral function monitoring, without which the diagnosis would have been missed or delayed for many hours. This case illustrates the value of cerebral function monitoring for patients in intensive care, where clinical signs of seizure activity are frequently masked by paralysis and sedation. Conclusion:, Limited availability of electroencephalogram (EEG) and cerebral function monitoring (CFM) in paediatric intensive care may inadvertently delay diagnosis and appropriate treatments and so adversely affect outcomes. We propose that round-the-clock cerebral function and/or EEG monitoring should be available in all centres that provide paediatric intensive care. [source] Skin Repair Using a Porcine Collagen I/III Membrane,Vascularization and Epithelization PropertiesDERMATOLOGIC SURGERY, Issue 6 2010FALK WEHRHAN MD BACKGROUND Collagen membranes have been developed to overcome the problem of limited availability of skin grafts. Vascularization and restricted functional epithelization limit the success of bioartificial constructs. OBJECTIVE To compare the vascularization, epithelization, and integration of a porcine collagen I/III membrane with that of split-thickness skin grafts on skin wounds. MATERIALS AND METHODS In 21 adult pigs, full-thickness skin defects on the rear side of the ear healed by split-thickness skin grafting, by covering with the membrane, or by free granulation. Skin samples on postoperative days 1, 3, 7, 14, 21, and 28 were evaluated histologically (hematoxylin-eosin, Sirius Red) and using immunohistochemistry (cytokeratin 5/6, transforming growth factor beta receptor (TGF,R-III) and immunoblot (TGF,1,3, Smad2/3). Epithelial thickness and TGF,R-III-positive capillary area were quantitatively assessed. RESULTS Epithelization and vascularization in the membrane group were not significantly different from in the group treated with a split-thickness skin graft. Free granulation showed significantly slower epithelization and vascularization (p<.05). TGF,1 and Smad2/3 complex expression were high during free granulation. Matrix was distinguishable until day 7. CONCLUSIONS This membrane serves as a suitable full-thickness dermal substitute, because the membrane is vascularized faster than free granulation tissue and enables early epithelization. Geistlich Biomaterials (Wolhusen, Switzerland) provided the collagen membrane used in this study [source] Patterning the heart, a template for human cardiomyocyte developmentDEVELOPMENTAL DYNAMICS, Issue 7 2006Susana M. Chuva de Sousa Lopes Abstract Although in mice, the dynamics of gene expression during heart development is well characterized, information on humans is scarce due to the limited availability of material. Here, we analyzed the transcriptional distribution of Mlc-2a, Mlc-1v, Mlc-2v, and atrial natriuretic factor (ANF) in human embryonic hearts between 7 and 18 weeks of gestation and in healthy and hypertrophic adult hearts by in situ hybridization and compared expression with that in mice. Strikingly, Mlc-2a, Mlc-1v, and ANF, which are essentially chamber-restricted in mice by mid-gestation, showed a broader distribution in humans. On the other hand, Mlc-2v may prove to be an adequate ventricular marker in humans in contrast to mouse. This study emphasizes the importance of careful comparative human,animal analyses during embryonic development and adulthood, as avoiding erroneous extrapolations may be critical to develop new and successful myocardial replacement therapies. Development Dynamics 235:1994,2002, 2006. © 2006 Wiley-Liss, Inc. [source] Prediction of metabolite identity from accurate mass, migration time prediction and isotopic pattern information in CE-TOFMS dataELECTROPHORESIS, Issue 14 2010Masahiro Sugimoto Abstract CE-TOFMS is a powerful method for profiling charged metabolites. However, the limited availability of metabolite standards hinders the process of identifying compounds from detected features in CE-TOFMS data sets. To overcome this problem, we developed a method to identify unknown peaks based on the predicted migration time (tm) and accurate m/z values. We developed a predictive model using 375 standard cationic metabolites and support vector regression. The model yielded good correlations between the predicted and measured tm (R=0.952 and 0.905 using complete and cross-validation data sets, respectively). Using the trained model, we subsequently predicted the tm for 2938 metabolites available from the public databases and assigned tentative identities to noise-filtered features in human urine samples. While 38.9% of the peaks were assigned metabolite names by matching with the standard library alone, the proportion increased to 52.2%. The proposed methodology increases the value of metabolomic data sets obtained from CE-TOFMS profiling. [source] A critical evaluation of genomic control methods for genetic association studiesGENETIC EPIDEMIOLOGY, Issue 4 2009Tony Dadd Abstract Population stratification is an important potential confounder of genetic case-control association studies. For replication studies, limited availability of samples may lead to imbalanced sampling from heterogeneous populations. Genomic control (GC) can be used to correct ,2 test statistics which are presumed to be inflated by a factor ,; this may be estimated by a summary ,2 value (,median or ,mean) from a set of unlinked markers. Many studies applying GC methods have used fewer than 50 unlinked markers and an important question is whether this can adequately correct for population stratification. We assess the behavior of GC methods in imbalanced case-control studies using simulation. SNPs are sampled from two subpopulations with intra-continental levels of FST (,0.005) and sampling schemata ranging from balanced to completely imbalanced between subpopulations. The sampling properties of ,median and ,mean are explored using 6,1,600 unlinked markers to estimate Type 1 error and power empirically. GC corrections based on the ,2 -distribution (GCmedian or GCmean) can be anti-conservative even when more than 100 single nucleotide polymorphisms (SNPs) are genotyped and realistic levels of population stratification exist. The GCF procedure performs well over a wider range of conditions, only becoming anti-conservative at low levels of , and with fewer than 25 SNPs genotyped. A substantial loss of power can arise when population stratification is present, but this is largely independent of the number of SNPs used. A literature survey shows that most studies applying GC have used GCmedian or GCmean, rather than GCF, which is the most appropriate GC correction method. Genet. Epidemiol. 2009. © 2008 Wiley Liss, Inc. [source] Survival of neural precursor cells in growth factor-poor environment: Implications for transplantation in chronic diseaseGLIA, Issue 4 2006Ofira Einstein Abstract A key issue for therapeutic neural stem cell transplantation in chronic diseases is the long-term survival of transplanted cells in the brain. The normal adult central nervous system does not support the survival of transplanted cells. Presumably, the limited availability of trophic factors maintains the survival of resident cells but is insufficient for supporting the survival of transplanted cells. Specifically, in multiple sclerosis, a chronic relapsing disease, it would be necessary to maintain long-term survival of transplanted cells through phases of relapses and remissions. It may be beneficial to transplant cells as early as possible, in a form that will keep their survival independent of tissue support and ready for immediate mobilization upon tissue demand during disease relapse. In the present study, we examined whether, in the form of neurospheres, multipotential neural precursor cells (NPCs) survive in a growth factor-poor environment while maintaining their potential to respond to environmental cues. We found that after removal of growth factors from the culture medium of neurospheres in vitro, NPC proliferation decreased significantly, but most cells survived for a prolonged time and maintained their stem cell characteristics. After re-exposure to growth factors, neurosphere cells resumed proliferation and could differentiate along neural lineages. Furthermore, neurospheres, but not single NPCs, that were transplanted into the brain ventricles of intact animals survived within the ventricles for at least a month and responded to induction of experimental autoimmune encephalomyelitis and brain inflammation by extensive migration into the brain white matter and differentiated into glial lineage cells. © 2005 Wiley-Liss, Inc. [source] Soil arthropods as indicators of water stress in Antarctic terrestrial habitats?GLOBAL CHANGE BIOLOGY, Issue 12 2003Peter Convey Abstract Abiotic features of Antarctic terrestrial habitats, particularly low temperatures and limited availability of liquid water, strongly influence the ecophysiology and life histories of resident biota. However, while temperature regimes of a range of land microhabitats are reasonably well characterized, much less is known of patterns of soil water stress, as current technology does not allow measurement at the required scale. An alternative approach is to use the water status of individual organisms as a proxy for habitat water status and to sample over several years from a population to identify seasonal or long-term patterns. This broad generalization for terrestrial invertebrates was tested on arthropods in the maritime Antarctic. We present analyses of a long-term data set of body water content generated by monthly sampling for 8,11 years of seven species of soil arthropods (four species of Acari, two Collembola and one Diptera) on maritime Antarctic Signy Island, South Orkney Islands. In all species, there was considerable within- and between-sample variability. Despite this, clear seasonal patterns were present in five species, particularly the two collembolans and a prostigmatid mite. Analyses of monthly water content trends across the entire study period identified several statistically significant trends of either increase or decrease in body water content, which we interpret in the context of regional climate change. The data further support the separation of the species into two groups as follows: firstly, the soft-bodied Collembola and Prostigmata, with limited cuticular sclerotization, which are sensitive to changes in soil moisture and are potentially rapid sensors of microhabitat water status, secondly, more heavily sclerotized forms such as Cryptostigmata (=Oribatida) and Mesostigmata mites, which are much less sensitive and responsive to short-term fluctuations in soil water availability. The significance of these findings is discussed and it is concluded that annual cycles of water content were driven by temperature, mediated via radiation and precipitation, and constituted reliable indicators of habitat moisture regimes. However, detailed ecophysiological studies are required on particular species before such information can be used to predict over long timescales. [source] Thawed cryoprecipitate stored for 6 h at room temperature: a potential alternative to factor VIII concentrate for continuous infusionHAEMOPHILIA, Issue 6 2004L. M. B. Pesquera-Lepatan Summary., Continuous infusion (CI) of factor VIII concentrates has been demonstrated to be cost-effective method in maintaining stable levels of FVIII activity in haemophilia A patients with major bleeding or undergoing major surgery. Cryoprecipitates remain the major source of FVIII in developing countries-like the Philippines because of limited availability and high cost of concentrates. To support the use of cryoprecipitate as alternative to FVIII concentrate for CI in centres with no factor concentrates, FVIII levels in 37 bags of random cryoprecipitate were measured at 0, 2, 4 and 6 h after thawing, kept at room temperature with bacteriological culture studies performed on the sixth hour. The mean FVIII content at hour 0 was 108.10 U per bag. Type ORh+ blood had lower FVIII content (±78.91 U per bag) compared with blood types ARh+ (±121.64 U per bag) and BRh+ (±117.04 U per bag). The units stored <6 months had higher FVIII content (±117.74 U per bag) compared with those stored for over 6- but <12-months (±66.77 U per bag). The mean rate of decline of FVIII activity at 2, 4 and 6 h was statistically significant at 10.35% (P = 0.000), 21.49% (P = 0.000) and 29.41% (P = 0.000) from baseline, respectively, using the paired t-test. Similar finding was found across different blood types and storage duration. Only one of 37 bags grew Staphylococcus aureus on day 10 of incubation. [source] Determinants of influenza vaccination timingHEALTH ECONOMICS, Issue 8 2005Byung Kwang Yoo Abstract New guidelines recommend different influenza vaccination timing for different subpopulations due to the limited availability of flu shots (FS). This study's objectives are to develop a theoretical model to demonstrate why some individuals choose to receive an early FS while others choose a late FS and to empirically explore the determinants of vaccination timing. Empirical results generally supported the theoretical results. Individuals vary their FS timing in response to variations in perceived risks, chronic condition levels reflecting their risk of influenza infection, and opportunity costs, measured by the presence of medical care other than an FS. Copyright © 2005 John Wiley & Sons, Ltd. [source] Pediatrics Access Problems in hemodialysis with a permanent central venous catheterHEMODIALYSIS INTERNATIONAL, Issue 1 2005J. Muscheites Hemodialysis is a common treatment of chronic renal failure, also in childhood. Due to the high standard of technique there are only few contraindications for this treatment at present. Limitations are given by the vessel access. But in the last years, hemodialysis has been made practicable by the permanent central venous catheter, however, with more problems. As an example for potential complications in the treatment with the permanent catheter we present an unusual case report about a twenty-one- year-old girl suffering from chronic renal failure due to reflux nephropathy, Prader-Willi- syndrome, myelonatrophia of undetermined origin with spastic diplegia of the legs, and increasing sphincter ani dysfunction. We started the renal replacement therapy when the girl was 15 years old. It was not possible to create an AV fistula due to very small vessels. Two Gore-Tex ® implants were clotted in absence of thrombophilia. Afterwards, the hemodialysis was performed by a permanent central venous catheter. The catheter had to be changed 15 times. The reasons for changing the catheter were problems of flow during hemodialysis due to clotting, dislocations, spontaneous removing of the catheter by herself, and infections. Altogether a sepsis occurred four times. The first transplantation failed due to a rupture of the transplanted kidney. A second transplantation was not possible because of the high BMI. Intermittently, the girl was treated with peritoneal dialysis (PD) in the hospital, because the PD couldn't be done at home due to different reasons. Only on weekends could the girl go home. The PD had to be finished after 6 months due to a severe psychotic syndrome. The girl died at age 21, caused by a sepsis following the 15th change of the catheter. A huge problem of frequent catheter changing is the limited availability of vessel accesses , the limits of treatment by hemodialysis. [source] Haematological parameters in severe acute respiratory syndromeINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2005W. J. CHNG Summary Clinical presentation of severe acute respiratory syndrome (SARS) is non-specific and isolation of all suspected patients is difficult because of the limited availability of isolation facilities. We studied changes in haematological parameters in SARS patients using median values analysed according to the day of symptom onset. White cell (WCC), absolute neutrophil, absolute lymphocyte (ALC) and platelet counts followed a v-shaped trend with the nadir at day 6 or 7 after symptom onset except for ALC in the ICU group that had not reached the nadir by day 12. None of our patients had a platelet count < 80 × 109/l and WCC < 2 × 109/l in the first 5 days of symptoms and these parameters may allow early stratification of febrile patients into likely and unlikely SARS cases to allow effective utilization of isolation facilities. On multivariate analysis, age is the only independent predictor for ICU admission. [source] Which Patients Benefit the Most from a Geriatrician's Care?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 10 2008Consensus Among Directors of Geriatrics Academic Programs Given the anticipated limited availability of geriatricians for the foreseeable future, how should the geriatrician's specialized clinical skills be deployed to optimally benefit the health of our aging population? Directors of geriatrics academic programs (DGAPs) at all 145 U.S. allopathic and osteopathic medical schools were asked this question as part of a winter 2007 on-line survey. The DGAPs were to indicate the types of patients who would most benefit from a geriatrician's services in three practice situations: primary care, consultations, and care in the hospital. The survey response rate was 74.5%. There was high consensus among the DGAPs on the benefits of having a geriatrician care for the most complex and vulnerable older adults in primary care and hospital settings. There was slightly less consensus as to when geriatrics consultations are beneficial. The patient subsets that were viewed as benefiting the most from geriatrician care were aged 85 and older, frailty, geriatric syndromes, severe functional impairment, and complexity. The results of this survey suggest that, because of the predicted shortage of geriatricians, the DGAPs would target geriatricians to work with the most vulnerable older adults. These findings offer the beginning of a consensus statement as to the role of geriatricians in the continuum of American medical care. [source] Extracorporeal immunoadsorption with protein A: Technical aspects and clinical resultsJOURNAL OF CLINICAL APHERESIS, Issue 1 2001G. Samuelsson The use of therapeutic plasma exchange (TPE) for removal of large molecular-weight substances form patients' circulation is limited by the method's non-selectivity and non-specificity. In order to remove the target amount of pathogenic substance, usually amounting to less than 1 g per liter of plasma, one will also remove 60-80 g of proteins, some of which are essential. A further disadvantage of the method is the need for substitution fluids, which at least in some countries are expensive and of limited availability. Furthermore, there is a (low) risk of disease transmission. To overcome these limitations, the principle of affinity chromatography used in biochemistry was applied in medicine to develop the Excorim Extracorporeal Immunoadsorption System in the beginning of the 1980s [1]. [source] Changes in the structure and composition of miombo woodlands mediated by elephants (Loxodonta africana) and fire over a 26-year period in north-western ZimbabweAFRICAN JOURNAL OF ECOLOGY, Issue 2 2009Isaac Mapaure Abstract Changes in structure and composition of miombo woodlands mediated by elephants and fire were studied in 26-year-old permanent transects established in 1972 in north-western Zimbabwe. Elephants caused 48% decline in proportions of large trees (>11 cm diameter), significant reductions (30.9,90.9%) in tree heights, reductions in stem areas (43.5%) and densities (2.5%) of all trees. There were increases in proportions of small trees (64.8%), shrub canopy volumes (271%) and shrub densities (172%). These increases are attributed to natural recruitment because of longer fire-free periods and reduction of tree suppression effects on lower strata as a result of elephant-induced tree declines. Frequencies of occurrence of most species dropped by 28,89.6%. Brachystegia boehmii was replaced by Pseudolachnostylis maprouneifolia as the most dominant tree, largely because of high elephant preference for Brachystegia boehmii. A new suite of species, dominated by Combretaceae, increased in dominance resulting in local floristic changes. Reductions in old elephant (33.4%), old unknown (89.9%) and new elephant (13.7%) damage suggest that elephant occupancy of miombo woodlands has declined, possibly because of limited availability of preferred browse species. This study clearly shows that elephants and fire have contributed significantly to the changes in miombo woodlands in the area. Résumé Les changements de la structure et de la composition des forêts de miombo dus aux éléphants et aux feux ont étéétudiés sur des transects permanents établis en 1972 dans le nord-ouest du Zimbabwe. Les éléphants ont causé un déclin de 48% de la proportion de grands arbres (>11 cm de diamètre), des réductions significatives (30,9,90,9%) de la hauteur des arbres, des réductions de la surface des tiges (43,5%) et de la densité (2,5%) de tous les arbres. Il y avait des augmentations de la proportion de petits arbres (64,8%), du volume des buissons (271%) et de leur densité (172%). Ces augmentations sont attribuées au recrutement naturel dûà de plus longues périodes sans feux, et à la réduction des effets suppressifs des arbres sur les couches inférieures due au déclin des arbres induit par les éléphants. La fréquence de la plupart des espèces a chuté de 28%à 89,6%. Brachystegia boehmi a été remplacé par Pseudolachnostylis maprouneifolia comme arbre dominant, en grande partie à cause de la forte préférence marquée par les éléphants pour Brachystegia boehmi. Une nouvelle série d'espèces, dominée par des Combrétacées, a accru sa dominance et entraîné des changements floristiques locaux. La réduction des dommages « anciens dus aux éléphants » (33,4%), « anciens d'origine inconnue » (,9,9%) et « nouveaux dus aux éléphants » (13,7%) suggère que l'occupation des forêts de miombo par les éléphants a diminué, peut-être à cause de la disponibilité limitée des espèces fourragères qu'ils préfèrent. Cette étude montre clairement que les éléphants et les feux ont contribué significativement aux changements survenus dans les forêts de miombo de la région. [source] Phylogenetic affinities of the Flabelligeridae (Annelida, Polychaeta)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 3 2008S. I. Salazar-Vallejo Abstract Cirratuliformia includes Acrocirridae, Cirratulidae, Ctenodrilidae, Flabelligeridae, Flotidae and Sternaspidae. The phylogenetic affinities have not been settled due to a limited availability of type or non-type material and the relationship between acrocirrids and flabelligerids have been problematical. In our study, the type material of all type species for all flabelligerid, and most acrocirrid genera have been studied and the morphological features have been used in a phylogenetic analysis. The results indicate that Acrocirridae, Ctenodrilidae, Fauveliopsidae, Flabelligeridae and Flotidae are monophyletic and that Sternaspidae falls within Cirratulidae; however, the latter conclusion might be reversed through increased taxon-sampling. The flabelligerid genera Brada, Flabelligera, Pherusa and Stylarioides each consists of several monophyletic groups and may be split. Conversely, Bradiella includes Diversibranchius, and the pelagic Buskiella includes Flota. The generic affinities of Poeobius remain uncertain, collecting better materials may resolve this issue. [source] Cryopreservation of primary human hepatocytes: The benefit of trehalose as an additional cryoprotective agentLIVER TRANSPLANTATION, Issue 1 2007Ekaterina Katenz Problems with the limited availability of human hepatocytes for cell transplantation may be overcome by efficient cryopreservation techniques and formation of appropriate cell banking. In this study we investigated the effect of the disaccharide trehalose on the cryopreservation of human hepatocytes. For analysis, liver cells were frozen in culture medium containing 10% dimethyl sulfoxide (DMSO) that was supplemented with varying concentrations of trehalose. During the postthawing culture period, viability, plating efficiency, total protein, cell proliferation, enzyme leakage, albumin and urea formation, as well as phase I and II metabolism were analyzed. In the pilot study, among the concentrations investigated, 0.2 M trehalose showed the best overall outcome. Compared to the use of DMSO alone, we found significant improvement in postthaw cell viability (62.9 ± 13 vs. 46.9 ± 11%, P < 0.01) and plating efficiency (41.5 ± 18 vs. 17.6 ± 13%, P < 0.01) in the trehalose group. The use of trehalose as an additive for cryopreserving human hepatocytes resulted in a significantly increased total protein level in the attached cells, higher secretion of albumin and a lower aspartate aminotransferase (AST) level after thawing. In conclusion, the use of trehalose as cryoprotective agent significantly improves the outcome of human hepatocyte cryopreservation. Liver Transpl, 2007. © 2006 AASLD. [source] Cystic fibrosis in India,PEDIATRIC PULMONOLOGY, Issue 12 2007S.K. Kabra Abstract Cystic fibrosis (CF) was considered to be non-existent in Indian subcontinent. Reports in last one decade have suggested that cystic fibrosis occurs in India but its precise magnitude is not known. Studies on migrant Indian population in United States and United Kingdom estimate frequency of CF as 1:10,000 to 1:40,000. The clinical features are similar to that reported in Caucasian population. CF in Indian children is usually diagnosed late and in advanced stage. Children are more malnourished and may have clinically evident deficiency of fat soluble vitamins. The frequency of clubbing, colonization with Pseudomonas, and laboratory evidence of pseudo-Bartter syndrome is relatively more at the time of diagnosis. Diagnostic facilities in form of sweat chloride estimation and genetic studies are not available readily. Mutation profile is different. The frequency of common mutation F508del in Indian children is between 19% and 34%. Other mutations are heterogeneous. Management of CF in India is difficult due to less number of trained manpower, limited availability, and high cost of pharmacologic agents. The determinants of early death include: severe malnutrition and colonization with Pseudomonas at the time of diagnosis, more than four episodes of lower respiratory infection per year and age of onset of symptoms before 2 months of age. To conclude, CF does occur in India; however, precise magnitude of problem is not known. There is need to create awareness amongst pediatricians, developing diagnostic facilities, and management protocols based on locally available resources. Pediatr Pulmonol. 2007; 42:1087,1094. © 2007 Wiley-Liss, Inc. [source] Accelerator mass spectrometry offers new opportunities for microdosing of peptide and protein pharmaceuticalsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 10 2010Mehran Salehpour Accelerator Mass Spectrometry (AMS) is an ultra-sensitive analytical method which has been instrumental in developing microdosing as a strategic tool in early drug development. Considerable data is available for AMS microdosing using typical pharmaceutical drugs with a molecular weight of a few hundred Daltons. The so-called biopharmaceuticals such as proteins offer interesting possibilities as drug candidates; however, experimental data for protein microdosing and AMS is scarce. The analysis of proteins in conjunction with early drug development and microdosing is overviewed and three case studies are presented on the topic. In the first case study AMS experimental data is presented, for the measured concentration of orally administered recombinant insulin in the blood stream of laboratory rabbits. Case study 2 concerns minimum sample size requirements. AMS samples normally require about 1,mg of carbon (10,µL of blood) which makes AMS analysis unsuitable in some applications due to the limited availability of samples such as human biopsies or DNA from specific cells. Experimental results are presented where the sample size requirements have been reduced by about two orders of magnitude. The third case study concerns low concentration studies. It is generally accepted that protein pharmaceuticals may be potentially more hazardous than smaller molecules because of immunological reactions. Therefore, future first-in-man microdosing studies might require even lower exposure concentrations than is feasible today, in order to increase the safety margin. This issue is discussed based on the current available analytical capabilities. Copyright © 2010 John Wiley & Sons, Ltd. [source] Insulin-Producing Cells Derived from Rat Bone Marrow and Their Autologous Transplantation in the Duodenal Wall for Treating DiabetesTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2009Yu-Hua Zhang Abstract Islet cell transplantation is one of the most promising therapies for diabetes mellitus (DM). However, the limited availability of purified islets for transplantation and the risk of immunological rejection severely limit its use. In vitro transdifferentiation of autologous bone marrow-derived mesenchymal stem cells (BMSCs) into insulin-producing cells (IPCs) could provide an abundant source of cells for this procedure and avoid immunological rejection. Here, we isolated and characterized BMSCs and induced their in vitro differentiation into IPCs. Reverse-transcription polymerase chain reaction analysis revealed that these IPCs could express Ins1, Ins2, glucagon, glucose transporter 2, and pancreatic duodenal homeobox-1. Insulin production by the IPCs was confirmed by immunocytochemistry and Western blot analysis. On this basis, donor rats supplying BMSCs were made diabetic by a single intraperitoneal injection of streptozotocin. The IPCs were then autologously transplanted into the duodenal submucosa of diabetic rats. Grafted cells could be visualized in sections after 2, 4, and 8 weeks by immunohistochemical staining for insulin. Furthermore, in the IPC-implanted group, hyperglycemia was normalized, compared with a persistent increase in glucose levels in the diabetic group and intraperitoneal glucose tolerance test-induced responses were observed in the IPC-implanted group. These results on autologous transplantation of IPCs derived from BMSCs into the duodenal wall could offer a novel potential therapeutical protocol for DM. Anat Rec, 292:728,735, 2009. © 2009 Wiley-Liss, Inc. [source] The impact of time duration between trades on the price of treasury note futures contractsTHE JOURNAL OF FUTURES MARKETS, Issue 10 2004Mark E. Holder Recent research in finance has indicated that the institutional structure in which financial asset prices are determined can have a nontrivial impact on pricing. This report examines transaction level data for Treasury Note futures contracts traded at the Chicago Board of Trade (CBOT) to identify institutional, or market microstructure, impacts on the pricing of these contracts. Relatively few articles have conducted empirical research on the microstructure of U.S. futures trading due to the limited availability of comprehensive transaction level data from the futures exchanges. This report uses the CBOT's Computerized Trade Reconstruction database, a comprehensive transaction level dataset, to identify the price impact of the time duration between trades in a manner analogous to that of A. Dufour and R. F. Engle (2000). Unique differences from prior research include the application to futures contracts with their relative higher frequency of trading, as well as the investigation of the price impact of the number of active traders present on the trading floor and the trading volume. Subsequent price and sign of trade significantly relate to the time duration between trades, the number of floor brokers, and the trading volume. © 2004 Wiley Periodicals, Inc. Jrl. Fut Mark 24:965,980, 2004 [source] Activation of T Cells by Cross-Linking Qa-2, the Ped Gene Product, Requires FynAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2007Sally R. De Fazio Problem Qa-2, the product of the Ped (preimplantation development) gene, regulates the rate of cell division of preimplantation mouse embryos by an unknown mechanism. Due to the limited availability of preimplantation embryos, T cells were used as a model system to assess the possible roles of Fyn and Lck, and two downstream effectors, PI-3 kinase and Akt, in Qa-2 induced cell proliferation. Method of study Resting T cells were stimulated to proliferate by treating with mouse anti-Qa-2 antibody, cross-linking with anti-mouse immunoglobulin, and adding PMA. The effects of kinase inhibitors on this proliferation were studied. Co-immunoprecipitates of T-cell lysates were analyzed for possible associations between Qa-2 and Fyn or Lck. Fyn knockout mice (Fyn,/,) were used to determine whether Fyn is required for T-cell activation induced by cross-linking Qa-2. Results An inhibitor of Src family kinases and inhibitors of PI-3 kinase and Akt suppressed proliferation of resting T cells induced by cross-linking Qa-2. Fyn, but not Lck, co-immunoprecipitated with Qa-2. Fyn,/, T cells failed to proliferate in response to Qa-2 cross-linking. Conclusion Fyn, PI-3 kinase, and Akt are required for the activation of T cells by cross-linking Qa-2. [source] Limitation of nocturnal import of ATP into Arabidopsis chloroplasts leads to photooxidative damage,THE PLANT JOURNAL, Issue 2 2007Thomas Reinhold Summary When grown in short day conditions and at low light, leaves of Arabidopsis plants with mutations in the genes encoding two plastidial ATP/ADP transporters (so-called null mutants) spontaneously develop necrotic lesions. Under these conditions, the mutants also display light-induced accumulation of H2O2 and constitutive expression of genes for copper/zinc superoxide dismutase 2 and ascorbate peroxidase 1. In the light phase, null mutants accumulate high levels of phototoxic protoporphyrin IX but have only slightly reduced levels of Mg protoporphyrin IX. The physiological changes are associated with reduced magnesium,chelatase activity. Since the expression of genes encoding any of the three subunits of magnesium,chelatase is similar in wild type and null mutants, decreased enzyme activity is probably due to post-translational modification which might be due to limited availability of ATP in plastids during the night. Surprisingly, the formation of necrotic lesions was absent when null mutants were grown either in long days and low light intensity or in short days and high light intensity. We ascribe the lack of lesion phenotype to increased nocturnal ATP supply due to glycolytic degradation of starch which may lead to additional substrate-level phosphorylation in the stroma. Thus, nocturnal import of ATP into chloroplasts represents a crucial, previously unknown process that is required for controlled chlorophyll biosynthesis and for preventing photooxidative damage. [source] Experience With the Levitronix CentriMag in the Pediatric Population as a Bridge to Decision and RecoveryARTIFICIAL ORGANS, Issue 11 2009Peter C. Kouretas Abstract Short-term mechanical circulatory support in the pediatric population with acute cardiac failure has traditionally been limited to extracorporeal membrane oxygenation given the limited availability of pediatric-sized pumps. The Levitronix CentriMag system (Thoratec Corporation, Pleasanton, CA, USA) offers expanded options for short-term support for this population. We report our experience with the successful use of the CentriMag in the pediatric population as a bridge to decision after postcardiotomy ventricular failure and as a bridge to recovery after heart transplantation. The first patient was bridged to a long-term HeartMate II (Thoratec Corporation) as a bridge to potential recovery. The second patient was supported after severe graft failure post heart transplantation, with a full recovery. The Levitronix CentriMag has proven to be a versatile, safe, and effective short-term circulatory support system for our pediatric patients. [source] Who is Better Off from Trade Liberalization?ASIAN ECONOMIC JOURNAL, Issue 3 2007An Experience from Urban China F16; O15; J31 Empirical studies have found that the skill wage gap (difference between wages earned by skilled and unskilled workers) narrowed in the case of the ,Four Asian Dragons' as they underwent trade liberalization during the 1960s and 1970s, whereas the gap widened in most of the Latin American countries after they liberalized their economies in the 1980s. China's integration into the world economy since 1978 has been used to explain this phenomenon, but few formal studies have been carried out in China regarding the effects of trade liberalization on the skill wage gap because of the limited availability of data. The present study uses unique household surveys conducted in ten provinces of China in 1988 and 1995 to study this issue. Results show that trade liberalization that occurred in China between 1988 and 1995 was responsible for an average increase of 28.73 yuan (approximately 20 percent of the total increase) in average monthly wages. However, trade liberalization significantly widened the urban skill wage gap in China by introducing an increase in income only for those who had 13 years or more of education (at least junior high school graduates). Interestingly, import liberalization also only benefited those who had more than 9 years of schooling; whereas export liberalization brought wage increases for people with 7,12 years of education. Finally, those with specific production skills from technical schools, rather than those with several years of general education, were mostly favored in the labor market in China between 1988 and 1995. [source] Population and species boundaries in the South American subterranean rodent Ctenomys in a dynamic environmentBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2010PATRICIA MIROL Subterranean rodents of the genus Ctenomys are an interesting system to assess the effects of habitat instability on the genetic structure of populations. The perrensi group is a complex of three species (C. roigi, C. perrensi and C. dorbignyi) and several forms of uncertain taxonomic status, distributed in the vicinity of the Iberá wetland in Argentina. Because of limited availability of suitable dry habitat, Ctenomys populations are distributed patchily around a vast mosaic of marshes, swamps and lagoons and become connected or isolated over time, depending particularly on the precipitation regime. Genetic variation at 16 microsatellite loci in 169 individuals collected in the area revealed eight clusters of populations which are thought to be evolutionary units, but which do not fit previous species limits. We interpret this lack of congruence between taxonomy and genetic structure as the result of a dynamic population structure. Where populations become connected, hybridization is possible. Where populations become isolated, rapid genetic divergence may occur. In the perrensi group, it appears that both of these factors disrupt the association between different genetic and morphological characters. The study of multiple characters is crucial to the understanding of the recent evolutionary history for dynamic systems such as this. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 368,383. [source] Nesting in a thermally challenging environment: nest-site selection in a rock-dwelling gecko, Oedura lesueurii (Reptilia: Gekkonidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2010DAVID A. PIKE In egg-laying species, maternal oviposition choice can influence egg survival and offspring phenotypes. According to the maternal-preference offspring-performance hypothesis, females should choose oviposition sites that are optimal for offspring fitness. However, in thermally challenging environments, maternal oviposition behaviour may be constrained by the limited availability of suitable oviposition sites. We investigated nest-site selection in a nocturnal lizard [velvet gecko Oedura lesueurii (Duméril and Bibron)] that inhabits a thermally challenging environment in south-eastern Australia. The viability of these gecko populations is critical for the persistence of an endangered snake species (Hoplocephalus bungaroides Wagler) that feeds heavily on velvet geckos. Female geckos chose nest sites nonrandomly, with 87% of nests (N = 30) being laid in deep crevices. By contrast, only 13% of clutches were laid under rocks, which were the most readily available potential nest sites. Nest success in crevices was high (100%), but no eggs hatched from nests under rocks. Temperatures in nest crevices remained relatively low and constant throughout the incubation period (mean = 22.7 °C, range 21.0,24.5 °C), whereas thermal regimes under rocks showed large diurnal fluctuations. Geckos selected crevices that were deeper, had less canopy cover, and were warmer than most available crevices; in 85% of cases, such crevices were used simultaneously by more than one female. The thermally distinctive attributes of nest sites, and their frequent communal use, suggest that nest sites are a scarce resource for female velvet geckos, and that the shading of rock outcrops through vegetation encroachment may influence nest success in this species. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 250,259. [source] Kinetic limitations of a bioelectrochemical electrode using carbon nanotube-attached glucose oxidase for biofuel cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009Xueyan Zhao Abstract Carbon nanotubes (CNTs) have been used for various bioelectrochemical applications, presumably for substantial improvement in performance. However, often only moderate results observed, with many governing factors have been considered and suggested yet without much systematic evaluation and verification. In this study, CNT-supported glucose oxidase (CNT,GOx) was examined in the presence of 1,4-benzoquinone (BQ). The intrinsic Michaelis parameters of the reaction catalyzed by CNT,GOx were found very close to those of native GOx. However, the Nafion entrapment of CNT,GOx for an electrode resulted in a much lower activity due to the limited availability of the embedded enzyme. Interestingly, kinetic studies revealed that the biofuel cell employing such an enzyme electrode only generated a power density equivalent to <40% of the reaction capability of the enzyme on electrode. It appeared to us that factors such as electron and proton transfer resistances can be more overwhelming than the heterogeneous reaction kinetics in limiting the power generation of such biofuel cells. Biotechnol. Bioeng. 2009; 104: 1068,1074. © 2009 Wiley Periodicals, Inc. [source] | |||||||||||||||||||