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91.
What's hot in animal biosafety? 总被引:1,自引:0,他引:1
Richmond JY Hill RH Weyant RS Nesby-O'Dell SL Vinson PE 《ILAR journal / National Research Council, Institute of Laboratory Animal Resources》2003,44(1):20-27
In recent years, the emergence or re-emergence of critical issues in infectious disease and public health has presented new challenges and opportunities for laboratory animal care professionals. The re-emergence of bioterrorism as a threat activity of individuals or small groups has caused a heightened awareness of biosecurity and improved biosafety. The need for animal work involving high-risk or high-consequence pathogens and for arthropod-borne diseases has stimulated renewed interest in animal biosafety matters, particularly for work in containment. Application of these principles to animals retained in outdoor environments has been a consequence of disease eradication programs. The anticipated global eradication of wild poliovirus has prompted the promulgation of new biosafety guidelines for future laboratory and animal work. Increased concern regarding the use of biologically derived toxins and hazardous chemicals has stimulated a new categorization of facility containment based on risk assessment. Recognition that prion disease agents and other high-consequence pathogens require safe handling and thorough destruction during terminal decontamination treatment has led to the development of new biosafety guidelines and technologies. The implementation of these guidelines and technologies will promote state-of-the-art research while minimizing risk to laboratory animals, researchers, and the environment. 相似文献
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93.
Smith EA Hill K Marlowe F Nolin D Wiessner P Gurven M Bowles S Mulder MB Hertz T Bell A 《Current anthropology》2010,51(1):19-34
We report quantitative estimates of intergenerational transmission and population-wide inequality for wealth measures in a set of hunter-gatherer populations. Wealth is defined broadly as factors that contribute to individual or household well-being, ranging from embodied forms such as weight and hunting success to material forms such household goods, as well as relational wealth in exchange partners. Intergenerational wealth transmission is low to moderate in these populations, but is still expected to have measurable influence on an individual's life chances. Wealth inequality (measured with Gini coefficients) is moderate for most wealth types, matching what qualitative ethnographic research has generally indicated (if not the stereotype of hunter-gatherers as extreme egalitarians). We discuss some plausible mechanisms for these patterns, and suggest ways in which future research could resolve questions about the role of wealth in hunter-gatherer social and economic life. 相似文献
94.
Lori J. Stark Stephanie Spear Richard Boles Elizabeth Kuhl Megan Ratcliff Cindy Scharf Christopher Bolling Joseph Rausch 《Obesity (Silver Spring, Md.)》2011,19(1):134-141
We evaluated the efficacy of a 6‐month clinic and home‐based behavioral intervention (Learning about Activity and Understanding Nutrition for Child Health; LAUNCH) to reduce obesity in preschool children ≥95th BMI percentile compared to enhanced standard of care (Pediatrician Counseling; PC). LAUNCH was a family‐based behavioral intervention that taught parents to use child behavior management strategies to increase healthy eating and activity for their children and themselves. PC presented the same diet and activity recommendations, but was delivered in a one‐time PC session. Eighteen children aged 2–5 years (mean 4.71 ± 1.01) with an average BMI percentile of 98 (±1.60) and an overweight parent were randomized to LAUNCH or PC. Assessments were conducted at baseline, 6 months (end of LAUNCH treatment) and 12 months (6 months following LAUNCH treatment). LAUNCH showed a significantly greater decrease on the primary outcomes of child at month 6 (post‐treatment) BMI z (?0.59 ± 0.17), BMI percentile (?2.4 ± 1.0), and weight gain (?2.7 kg ± 1.2) than PC and this difference was maintained at follow‐up (month 12). LAUNCH parents also had a significantly greater weight loss (?5.5 kg ± 0.9) at month 6 and 12 (?8.0 kg ± 3.5) than PC parents. Based on the data from this small sample, an intensive intervention that includes child behavior management strategies to improve healthy eating and activity appears more promising in reducing preschool obesity than a low intensity intervention that is typical of treatment that could be delivered in primary care. 相似文献
95.
The aim of this work was to test the hypothesis that changes in cytosolic 3-phosphoglyceric acid (3-PGA) content can regulate the rate of starch synthesis in potato (Solanum tuberosum L.) tubers. The amount of 3-PGA was increased by expressing bacterial phosphofructokinase (PFK; EC 2.7.1.11) in transgenic potato tubers. The resultant 3-fold increase in PFK activity was accompanied by an increase in metabolites downstream of PFK, including a 3-fold increase in 3-PGA. There was also a decrease in metabolites upstream of PFK, most notably of glucose-6-phosphate. The increase in 3-PGA did not affect the amount of starch that accumulated in developing tubers, nor its rate of synthesis in tuber discs cut from developing tubers. This suggests that changes in cytosolic 3-PGA may not affect the rate of starch synthesis under all circumstances. We propose that in this case, a decrease in glucose-6-phosphate (which is transported into the amyloplast as a substrate for starch synthesis) may be sufficient to counteract the effect of increased 3-PGA. 相似文献
96.
Effects of roads and land use on frog distributions across spatial scales and regions in the Eastern and Central United States 下载免费PDF全文
David M. Marsh Bradley J. Cosentino Kara S. Jones Joseph J. Apodaca Karen H. Beard Jane Margaret Bell Christine Bozarth Derrick Carper Julie F. Charbonnier Andreia Dantas Elizabeth A. Forys Miran Foster Jaquelyn General Kristen S. Genet Macie Hanneken Kyle R. Hess Shane A. Hill Faisal Iqbal Nancy E. Karraker Eran S. Kilpatrick Tom A. Langen James Langford Kathryn Lauer Alison J. McCarthy Joseph Neale Saumya Patel Austin Patton Cherie Southwick Nathaniel Stearrett Nicholas Steijn Mohammad Tasleem Joseph M. Taylor James R. Vonesh 《Diversity & distributions》2017,23(2):158-170
97.
98.
Stephen Sidney Cora E. Lewis James O. Hill Charles P. Quesenberry Elizabeth R. Stamm Ann Scherzinger Kimberly Tolan Bruce Ettinger 《Obesity (Silver Spring, Md.)》1999,7(3):265-272
SIDNEY, STEPHEN, CORA E. LEWIS, JAMES O. HILL, CHARLES P. QUESENBERRY, JR, ELIZABETH R. STAMM, ANN SCHERZINGER, KIMBERLY TOLAN, AND BRUCE ETTINGER. Association of total and central adiposity measures with fasting insulin in a biracial population of young adults with normal glucose tolerance: the CARDIA study. Obes Res. Objective: To determine the association of computed tomography (CT)-measured visceral adipose tissue (AT) and other measures of adiposity with fasting insulin in a biracial (African American and Caucasian) study population of young adults. Research Methods and Procedures: The study population consisted of 251 young adults with normal glucose tolerance (NGT), ages 28–40 years, who were volunteers from the Birmingham, Alabama, and Oakland, California centers of the Coronary Artery Risk Development in Young Adults (CARDIA) study. Results: In regression models with total adiposity measures (body mass index or dual-energy X-ray absorptiometry-measured percent fat), visceral AT (measured as a cross-sectional area in cm2) was generally a stronger predictor of insulin than overall adiposity in all race/gender groups (partial correlation coefficients ranging from 0. 31 to 0. 47) except for black men, in whom the associations were nonsignificant. Partial correlation coefficients between waist circumference and insulin, controlling for percent fat, were nearly identical to those between visceral AT and insulin in women and in white men. Analyses performed on 2060 NGT CARDIA subjects who were not in this study of visceral AT showed significant correlations of waist circumference with insulin in all racelgender groups, including black men, and that black men in the visceral AT study group were significantly leaner than other black male CARDIA subjects. Discussion: We conclude that visceral AT was associated with fasting insulin in NGT participants in three of the four race/gender groups (black men excepted) and that waist circumference was a good surrogate for visceral AT in examining associations of central adiposity with fasting insulin. 相似文献
99.
Effects of acriflavine on the mitochondria and kinetoplast of Crithidia fasciculata. Correlation of fine structure changes with decreased mitochondrial enzyme activity 总被引:1,自引:1,他引:1 下载免费PDF全文
The effects of acriflavine on the fine structure and function of the mitochondria and the kinetoplast in Crithidia fasciculata have been investigated. A mitochondrial fraction was prepared by differential centrifugation of cells broken by grinding with neutral alumina. Isolated mitochondria or intact cells revealed by spectrophotometric measurements the presence of cytochromes a + a
3, b, c
555 and o. After cells were grown in acriflavine for 3–4 days, the fine structure of the mitochondria and their cytochrome content were affected. Cells grown in 5.0 µM acriflavine had a threefold decrease in cytochrome a + a
3 and decreased respiratory activity. The mitochondrial preparation from these cells had a fivefold decrease in cytochrome a + a
3 and a less but significant decrease of other cytochromes present. There was also a decrease in the mitochondrial enzyme activities of NADH, succinic and L-α-glycerophosphate oxidases, and succinic and L-α-glycerophosphate dehydrogenases. Dyskinetoplastic cells could be demonstrated after growth in 1.0 µM acriflavine. At 5 µM, 80–90% of the cells were dyskinetoplastic. The kinetoplastic DNA was condensed, nonfibrillar, and did not incorporate thymidine-3H. The mitochondria in these cells had few cristae and were shorter and more swollen than the controls. Acriflavine may induce the fine structure effects we have observed and may affect the formation of the mitochondria in C. fasciculata. 相似文献
100.
Sarah J. Hill Allison P. Clark Daniel P. Silver David M. Livingston 《Molecular and cellular biology》2014,34(20):3828-3842
Sporadic basal-like cancers (BLCs) are a common subtype of breast cancer that share multiple biological properties with BRCA1-mutated breast tumors. Despite being BRCA1+/+, sporadic BLCs are widely viewed as phenocopies of BRCA1-mutated breast cancers, because they are hypothesized to manifest a BRCA1 functional defect or breakdown of a pathway(s) in which BRCA1 plays a major role. The role of BRCA1 in the repair of double-strand DNA breaks by homologous recombination (HR) is its best understood function and the function most often implicated in BRCA1 breast cancer suppression. Therefore, it is suspected that sporadic BLCs exhibit a defect in HR. To test this hypothesis, multiple DNA damage repair assays focused on several types of repair were performed on a group of cell lines classified as sporadic BLCs and on controls. The sporadic BLC cell lines failed to exhibit an overt HR defect. Rather, they exhibited defects in the repair of stalled replication forks, another BRCA1 function. These results provide insight into why clinical trials of poly(ADP-ribose) polymerase (PARP) inhibitors, which require an HR defect for efficacy, have been unsuccessful in sporadic BLCs, unlike cisplatin, which elicits DNA damage that requires stalled fork repair and has shown efficacy in sporadic BLCs. 相似文献