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41.
Jonathan Balcombe Hope Ferdowsian Debra Durham 《Journal of applied animal welfare science : JAAWS》2013,16(4):361-370
Although measures to control bovine spongiform encephalopathy (BSE) had been in force in the United Kingdom for many years and had resulted in a marked decline in clinical cases, the announcement by the Secretary of State for Health on March 20, 1996, that a new variant form of Creutzfeldt-Jakob Disease may be linked with exposure to BSE, resulted in the introduction of several new control measures. These measures included a scheme banning human consumption of meat from cattle who were more than 30 months old (the so-called "over 30-month scheme;" OTMS), a subsidy for slaughter of calves, and additional inspections of abattoirs. The altered slaughter procedures and lack of rendering facilities meant an initial backlog of OTMS animals having to remain on farms. This placed pressures on accommodation and feed stocks, the latter being in short supply because of a poor grass growth the previous summer. Initially, the long delay before the removal of casualty animals from the farm resulted in increased summer mastitis problems for nonlactating cows. The export of calves to the European Union for veal production was banned, thereby allowing the cessation of a previously legal trade that was considered distasteful by many members of the general public. Financial concerns disturbed and continue to disturb affected farmers. 相似文献
42.
The current study investigated the accident rates across morning, late, and night shifts in rotating shift-workers employed in two different shift rotations at the same steel work factory. A retrospective analysis has been performed of accident data (N = 578) over a 5-year period (2003 through 2007) of 730 male shift-workers employed in either a clockwise (mean age of the workers 38.1 ± SD 9.8 years) or counterclockwise rotation (mean age 38.0 ± SD 10.1 years) with comparable work conditions. The overall accident rate across the 24-h day was not significantly different between clockwise and counterclockwise shift rotation. In both shift-work rotations, morning shifts as opposed to night shifts exhibited a significantly higher accident rate. There was no significant difference between late shifts and morning or night shifts in either shift rotation. The increased accident rate in the morning shift at this steel factory could be related to the early starting time of the shift and to this shift being more labor intensive in both shift rotations. These findings suggest that work-related factors must be considered in addition to shift-work schedules when investigating accident rates in rotating shift-workers. 相似文献
43.
Abstract Fast atom bombardment (FAB) mass spectrometry, a new ionization technique, has been applied to a variety of polar, nonvolatile compounds with considerable success. Current literature regarding the analysis of nucleosides, nucleotides and oligonucleotides using FAB is reviewed. 相似文献
44.
Aim Small (< 1 km2) alpine glaciers are likely to disappear in this century, resulting in decreased regional habitat heterogeneity in associated streams. Both heterogeneity within and spatial isolation among glacier‐influenced streams can enhance beta diversity of stream‐dwelling organisms. We measured beta at both community and population‐genetic levels within and among streams currently influenced by small Pyrenean glaciers. We aimed to evaluate whether patterns are analogous between the two levels, to apply various approaches for characterizing beta, and to infer the outcome of future glacier loss on regional biodiversity. Location Four glacier‐fed basins in the Parc National des Pyrénées, France. Methods We classified each of 18 stream reaches across the basins into either high‐, mid‐ or low‐‘glaciality’ (glacial influence) groups according to four physicochemical characteristics. At each reach, we collected macroinvertebrate communities and evaluated mitochondrial DNA haplotypes for 11–13 individuals of Baetis alpinus Pictet. Using taxa/haplotypes as basic units, we evaluated community and population‐genetic beta diversity simultaneously. We measured beta diversity in three major ways: as multivariate (Sørensen's dissimilarity, Jost D) and ‘classical’ (gamma/alpha) variation to compare among glaciality groups, and as turnover along the glaciality gradient within each basin. Results For most approaches at both organizational levels, beta was greatest among high‐glaciality reaches, absolute values of variation of beta in high‐glaciality streams were strikingly similar between levels, and the steepest turnover within basins occurred between high‐ and mid‐glaciality reaches. Therefore, high‐glaciality reaches contained assemblages and populations that were unique both within that stream type (among basins) and compared with other stream types within basins. Main conclusions Parallel beta diversity patterns at population‐genetic and community levels suggested that environmental drivers influence these levels analogously. Extreme conditions (e.g. low temperature, high instability, isolation) in high‐glaciality streams probably enhance beta at both levels. Stream beta diversity is likely to decrease substantially with continued glacial reduction in this system. 相似文献
45.
Hanna Rennert Debra G.B. Leonard Melissa Cushing Carmen Azurin Tsiporah Shore 《Cytotherapy》2013,15(3):391-395
Background aimsAn accurate and reliable assessment of bone marrow engraftment (BME) after hematopoietic stem cell transplantation (HSCT) is based on the ability to distinguish between recipient and donor cells at selected polymorphic short tandem repeat (STR) DNA loci. Buccal cells are an important source of DNA for determining the recipient's constitutional genotype, particularly in patients transplanted before the STR evaluation.MethodsGenomic DNA was extracted from the recipient buccal cells and from isolated CD3+ (T-cell lymphocyte) and CD33+ (myelocyte) cells after HSCT. BME analysis was performed using a STR-based polymerase chain reaction amplification method followed by fragment-size analysis for assessing the recipient-derived or donor-derived composition of cell lineage-specific peripheral blood DNA.ResultsWe identified three cases of complete buccal epithelial cell engraftment after HSCT detected by BME analysis, potentially leading to misinterpretation of testing results if these cells were used as the sole source for determining the recipient's genotype.ConclusionsThese cases suggest that complete engraftment of buccal epithelial cells may be a common finding in patients receiving HSCT, drawing attention to important issues such as the type of samples used for determining a patient's constitutional genotype that may confound testing results. This study also highlights the need for careful interpretation of the BME testing results in the context of the clinical findings. 相似文献
46.
Kiterie M. E. Faller Debra J. Medway Dunja Aksentijevic Liam Sebag-Montefiore Jürgen E. Schneider Craig A. Lygate Stefan Neubauer 《PloS one》2013,8(6)
Background
Reduced levels of creatine and total adenine nucleotides (sum of ATP, ADP and AMP) are hallmarks of chronic heart failure and restoring these pools is predicted to be beneficial by maintaining the diseased heart in a more favourable energy state. Ribose supplementation is thought to support both salvage and re-synthesis of adenine nucleotides by bypassing the rate-limiting step. We therefore tested whether ribose would be beneficial in chronic heart failure in control mice and in mice with elevated myocardial creatine due to overexpression of the creatine transporter (CrT-OE).Methods and Results
Four groups were studied: sham; myocardial infarction (MI); MI+ribose; MI+CrT-OE+ribose. In a pilot study, ribose given in drinking water was bioavailable, resulting in a two-fold increase in myocardial ribose-5-phosphate levels. However, 8 weeks post-surgery, total adenine nucleotide (TAN) pool was decreased to a similar amount (8–14%) in all infarcted groups irrespective of the treatment received. All infarcted groups also presented with a similar and substantial degree of left ventricular (LV) dysfunction (3-fold reduction in ejection fraction) and LV hypertrophy (32–47% increased mass). Ejection fraction closely correlated with infarct size independently of treatment (r2 = 0.63, p<0.0001), but did not correlate with myocardial creatine or TAN levels.Conclusion
Elevating myocardial ribose and creatine levels failed to maintain TAN pool or improve post-infarction LV remodeling and function. This suggests that ribose is not rate-limiting for purine nucleotide biosynthesis in the chronically failing mouse heart and that alternative strategies to preserve TAN pool should be investigated. 相似文献47.
Jing Fang Siddharth Sukumaran Debra C. DuBois Richard R. Almon William J. Jusko 《PloS one》2013,8(12)
A retrospective meta-modeling analysis was performed to integrate previously reported data of glucocorticoid (GC) effects on glucose regulation following a single intramuscular dose (50 mg/kg), single intravenous doses (10, 50 mg/kg), and intravenous infusions (0.1, 0.2, 0.3 and 0.4 mg/kg/h) of methylprednisolone (MPL) in normal and adrenalectomized (ADX) male Wistar rats. A mechanistic pharmacodynamic (PD) model was developed based on the receptor/gene/protein-mediated GC effects on glucose regulation. Three major target organs (liver, white adipose tissue and skeletal muscle) together with some selected intermediate controlling factors were designated as important regulators involved in the pathogenesis of GC-induced glucose dysregulation. Assessed were dynamic changes of food intake and systemic factors (plasma glucose, insulin, free fatty acids (FFA) and leptin) and tissue-specific biomarkers (cAMP, phosphoenolpyruvate carboxykinase (PEPCK) mRNA and enzyme activity, leptin mRNA, interleukin 6 receptor type 1 (IL6R1) mRNA and Insulin receptor substrate-1 (IRS-1) mRNA) after acute and chronic dosing with MPL along with the GC receptor (GR) dynamics in each target organ. Upon binding to GR in liver, MPL dosing caused increased glucose production by stimulating hepatic cAMP and PEPCK activity. In adipose tissue, the rise in leptin mRNA and plasma leptin caused reduction of food intake, the exogenous source of glucose input. Down-regulation of IRS-1 mRNA expression in skeletal muscle inhibited the stimulatory effect of insulin on glucose utilization further contributing to hyperglycemia. The nuclear drug-receptor complex served as the driving force for stimulation or inhibition of downstream target gene expression within different tissues. Incorporating information such as receptor dynamics, as well as the gene and protein induction, allowed us to describe the receptor-mediated effects of MPL on glucose regulation in each important tissue. This advanced mechanistic model provides unique insights into the contributions of major tissues and quantitative hypotheses for the multi-factor control of a complex metabolic system. 相似文献
48.
Monica K. Borucki Haiyin Chen-Harris Victoria Lao Gilda Vanier Debra A. Wadford Sharon Messenger Jonathan E. Allen 《PLoS neglected tropical diseases》2013,7(11)
One of the hurdles to understanding the role of viral quasispecies in RNA virus cross-species transmission (CST) events is the need to analyze a densely sampled outbreak using deep sequencing in order to measure the amount of mutation occurring on a small time scale. In 2009, the California Department of Public Health reported a dramatic increase (350) in the number of gray foxes infected with a rabies virus variant for which striped skunks serve as a reservoir host in Humboldt County. To better understand the evolution of rabies, deep-sequencing was applied to 40 unpassaged rabies virus samples from the Humboldt outbreak. For each sample, approximately 11 kb of the 12 kb genome was amplified and sequenced using the Illumina platform. Average coverage was 17,448 and this allowed characterization of the rabies virus population present in each sample at unprecedented depths. Phylogenetic analysis of the consensus sequence data demonstrated that samples clustered according to date (1995 vs. 2009) and geographic location (northern vs. southern). A single amino acid change in the G protein distinguished a subset of northern foxes from a haplotype present in both foxes and skunks, suggesting this mutation may have played a role in the observed increased transmission among foxes in this region. Deep-sequencing data indicated that many genetic changes associated with the CST event occurred prior to 2009 since several nonsynonymous mutations that were present in the consensus sequences of skunk and fox rabies samples obtained from 20032010 were present at the sub-consensus level (as rare variants in the viral population) in skunk and fox samples from 1995. These results suggest that analysis of rare variants within a viral population may yield clues to ancestral genomes and identify rare variants that have the potential to be selected for if environment conditions change. 相似文献
49.
Barry E. Kennedy Veronique G. LeBlanc Tiffany M. Mailman Debra Fice Ian Burton Tobias K. Karakach Barbara Karten 《PloS one》2013,8(12)
Niemann-Pick Type C (NPC) disease is an autosomal recessive neurodegenerative disorder caused in most cases by mutations in the NPC1 gene. NPC1-deficiency is characterized by late endosomal accumulation of cholesterol, impaired cholesterol homeostasis, and a broad range of other cellular abnormalities. Although neuronal abnormalities and glial activation are observed in nearly all areas of the brain, the most severe consequence of NPC1-deficiency is a near complete loss of Purkinje neurons in the cerebellum. The link between cholesterol trafficking and NPC pathogenesis is not yet clear; however, increased oxidative stress in symptomatic NPC disease, increases in mitochondrial cholesterol, and alterations in autophagy/mitophagy suggest that mitochondria play a role in NPC disease pathology. Alterations in mitochondrial function affect energy and neurotransmitter metabolism, and are particularly harmful to the central nervous system. To investigate early metabolic alterations that could affect NPC disease progression, we performed metabolomics analyses of different brain regions from age-matched wildtype and Npc1
-/- mice at pre-symptomatic, early symptomatic and late stage disease by 1H-NMR spectroscopy. Metabolic profiling revealed markedly increased lactate and decreased acetate/acetyl-CoA levels in Npc1
-/- cerebellum and cerebral cortex at all ages. Protein and gene expression analyses indicated a pre-symptomatic deficiency in the oxidative decarboxylation of pyruvate to acetyl-CoA, and an upregulation of glycolytic gene expression at the early symptomatic stage. We also observed a pre-symptomatic increase in several indicators of oxidative stress and antioxidant response systems in Npc1
-/- cerebellum. Our findings suggest that energy metabolism and oxidative stress may present additional therapeutic targets in NPC disease, especially if intervention can be started at an early stage of the disease. 相似文献
50.
Alan Daugherty Debra L. Rateri Deborah A. Howatt Richard Charnigo Lisa A. Cassis 《PloS one》2013,8(4)