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1.
2.
Conduct,Oversight, and Ethical Considerations of Clinical Trials in Companion Animals with Cancer: Report of a Workshop on Best Practice Recommendations
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R. Page P. Baneux D. Vail L. Duda P. Olson L. Anestidou N. Dybdal G. Golab W. Shelton M. Salgaller C. Hardy 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2016,30(2):527-535
Development of effective and safe treatments for companion animals with cancer requires the collaboration of numerous animal health professionals and the full engagement of animal owners. Establishing ‘Best Practice Recommendations’ for clinical trials in veterinary oncology represents an important step toward meeting the goal of rigorous clinical trial design and conduct that is required to establish valid evidence. Likewise, optimizing patient welfare and owner education and advocacy is crucial to meet the unique ethical obligations to both owners and animals enrolled in these clinical trials and to ensure trust in the team conducting the research. To date, ‘Best Practice Recommendations’ for clinical trial conduct have not been reported for veterinary oncology. This document summarizes the consensus of a workshop held in November, 2014 to identify relevant ethical principles and to ensure responsible conduct of clinical research in companion animals with cancer. It is intended as a working document that will be updated as advances in science and ethical considerations require. To the extent possible, existing guidelines for the conduct and oversight of clinical trials in humans have been adapted for veterinary trials to avoid duplicative effort and to facilitate integration of clinical trials such that translational research with benefits for both companion animals and humans are encouraged. 相似文献
3.
A Homozygous RAB3GAP1:c.743delC Mutation in Rottweilers with Neuronal Vacuolation and Spinocerebellar Degeneration
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4.
Analysis of amino acid uptake and translocation in Arabidopsis with a low‐cost hydroponic system
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In soils, amino acids may be an important source of nitrogen for plants, at least in those where organic matter is not quickly degraded. The physiology of uptake of amino acids by roots was mainly studied in the 70's and 80's, before genes encoding amino acid importers were cloned in the 90's. While two families of amino acid transporters have been identified, yielding a total of about 100 genes, the role of each member is yet to be elucidated. As a tool for studying the role of amino acid transporters from Arabidopsis we set up a new hydroponic system suitable for radioisotope use. This system enables reproducible amino acid uptake by roots and estimation of the transport to the shoots of the amino acid taken up. We show that the rates of glutamine (Gln) uptake by wild‐type roots and transfer to the shoots were linear, and that other tested amino acids were translocated to the shoots with lower efficiency than Gln. A T‐DNA insertion mutant for a Gln exporter was compared to the wild‐type plants. Gln uptake and transfer were similar in both genotypes, showing that the suppression of the exporter did not affect uptake or transfer of amino acids to the shoots. The main advantage of the hydroponic system presented here is that all the materials used to grow Arabidopsis are virtually free and can therefore be discarded, a useful feature when working with radioactivity. 相似文献
5.
Anne H. Beaudreau Eric J. Ward Richard E. Brenner Andrew O. Shelton Jordan T. Watson Jennifer C. Womack Sean C. Anderson Alan C. Haynie Kristin N. Marshall Benjamin C. Williams 《Fish and Fisheries》2019,20(4):601-619
Heterogeneity in human responses and decision‐making can contribute to the resilience of social–ecological systems in the face of environmental, political and economic pressures. In fishery systems worldwide, the ability of harvesters to maintain a diverse portfolio of fishing strategies is important for building adaptive capacity. We used a case‐study approach to examine the complexity of factors that inhibit or promote diversification in fisheries of Alaska, one of the major fishing regions of the world. Through a combination of harvest records and literature review, we explored shifts in participation and portfolio diversity in Alaskan fisheries over three decades. The four case‐studies examined the responses of fishers, fleets and communities to multiple, intersecting pressures, including biological declines, market and price dynamics, fishery privatization and the 1989 Exxon Valdez oil spill. These cases illustrate how stressors acting at multiple scales can encourage or constrain opportunities for diversification, and that these opportunities may be spread inequitably across participants. Overall, we found evidence for reduced participation and increasing specialization in Alaskan commercial fisheries. While numerous factors explain these trends, policies like individual quota systems and the increasing cost of entry into fisheries are forcing consolidation at local to regional scales. A portfolio approach to managing fisheries that reduces barriers to diversification and includes broad representation of resource users and communities in management may help to maintain opportunity and choice for fishers. 相似文献
6.
Shelton GD Liu LA Guo LT Smith GK Christiansen JS Thomas WB Smith MO Kline KL March PA Flegel T Engvall E 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):240-244
The most common form of muscular dystrophy in dogs and humans is caused by mutations in the dystrophin gene. The dystrophin gene is located on the X chromosome, and, therefore, disease-causing mutations in dystrophin occur most often in males. Therefore, females with dystrophin deficiency or other forms of muscular dystrophy may be undiagnosed or misdiagnosed. Immunohistochemistry was used to analyze dystrophin and a number of other muscle proteins associated with muscular dystrophy in humans, including sarcoglycans and laminin alpha2, in muscle biopsy specimens from 5 female dogs with pathologic changes consistent with muscular dystrophy. The female dogs were presented with a variety of clinical signs including generalized weakness, muscle wasting, tremors, exercise intolerance, gait abnormalities, and limb deformity. Serum creatine kinase activity was variably high. One dog had no detectable dystrophin in the muscle; another was mosaic, with some fibers normal and others partly dystrophin-deficient. A 3rd dog had normal dystrophin but no detectable laminin alpha2. Two dogs could not be classified. This study demonstrates the occurrence of dystrophin- and laminin alpha2-associated muscular dystrophy and the difficulty in clinical diagnosis of these disorders in female dogs. 相似文献
7.
8.
Poncelet L Résibois A Engvall E Shelton GD 《The Journal of small animal practice》2003,44(12):550-552
A European case of laminin alpha2 deficiency-associated muscular dystrophy in a 12-month-old, female Maine coon pedigree cat is reported. The history and eventual clinical presentation of this cat differed from those of two cats reported in the USA. In this case, the myopathy was characterised by progressively worsening weakness, muscle atrophy and joint contracture. Tendon reflexes were diminished, and motor nerve conduction velocities were slowed. Muscle biopsy demonstrated a dystrophic phenotype with endomysial fibrosis. Occasional thinly myelinated nerve fibres were present within a peripheral nerve specimen. Poorly myelinated fibres were also found at the root level on necropsy specimens. Immunohistochemical staining revealed the absence of laminin alpha2. The cat's family history did not indicate genetic transmission of the disease. 相似文献
9.
Steven D. Mims William L. Shelton Otomar Linhart Changzheng Wang 《Journal of the World Aquaculture Society》1997,28(4):334-343
Viable, diploid gynogenetic (gynogenotes) paddlefish Polyodon spathula were produced by activating eggs with ultraviolet-irradiated shovelnose sturgeon Scaphirhynchus platorynchus spermatozoa and heat shocking. Without irradiation treatment, sturgeon spermatozoa appeared to activate the eggs (up to gastrulation), but did not result in any viable hybrids. Experiment 1 determined that heat-shock treatment of 35 C for a 2-min duration within the interval of 2–22 min post-activation resulted in highest yield of gynogenotes (12–19%) from eggs incubated at 18 C. Experiment 2 applied the heat shock treatment at 35 C from 14.0 to 28.0 min in 2-min intervals after activation at 18 C for a larger scale of gynogenetic production. Both experiments showed that the best yields of gynogenotes were obtained when the heat shock treatment occurred at 16, 18, and 20 min after activation. When these times were expressed in terms of τ0 . units (duration of one mitotic cycle of synchronous cell division related to water temperatures), optimal activations were 0.26, 0.29, and 0.32τ0 (τ0 @ 18 C = 63.5 min). Experiment 3 tested the utility of τ0 . at two different pre-shock incubation water temperatures of 18 C and 16 C, and determined that there was no significant interaction in percentage of viable gynogenotes between two different incubation temperatures and the mitotic intervals (0.21, 0.26, 0.31, 0.36, 0.41τ0 ) tested. Best survival of gynogenotes occurred when eggs held at either pre-shock incubation water temperatures were shocked at 0.26τ0 All gynogenotes examined were histologically confirmed to have ovarian tissue and were determined to have similar oocyte development to that of normal female (control) paddlefish. 相似文献
10.
Grady H. Shelton DVM Chris K. Grant PhD DSc Michael L. Linenberger MD Janis L. Abkowitz MD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1990,4(6):317-319
Griseofulvin administration was associated with the development of absolute neutropenia in six of seven (86%) cats with feline immunodeficiency virus (FIV) infection. The neutropenia was severe (less than 400 neutrophils/microliter) in four of the six affected cats, and one cat died from sepsis. Neutrophil counts returned to baseline values within 15 days after drug withdrawal in all surviving cats. No symptoms or hematologic abnormalities were observed in four normal (FIV-seronegative) cats treated with the same lot of griseofulvin at equivalent doses. Neutropenia recurred in two of two FIV-seropositive cats upon griseofulvin rechallenge. Cats with FIV infections appear to be at increased risk for griseofulvin-associated neutropenia. This phenomenon may be analogous to the increased frequency of antibiotic-induced neutropenias observed in humans infected with the human immunodeficiency virus. 相似文献