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61.
The JCR:LA-cp rat is a strain carrying the mutant cp (corpulent) gene. Animals that are homozygous cp are hyperphagous, hyperinsulinemic, hyperlipidemic, and obese. Corpulent male rats, but not females or lean rats, develop atherosclerotic lesions and myocardial lesions. Since the myocardial lesions are apparently of ischemic origin, the noradrenergic system and vascular hyperactivity and vasospasm may play a role in the pathogenesis. To test this we have studied the brain contents of the amines norepinephrine, dopamine, and 5-hydroxtryptamine and their breakdown products and depleted the peripheral sympathetic terminals with 6-hydroxydopamine. Only 5-hydroxytryptamine and 5 hydroxyindole-3-acetic acid were present at higher concentrations in the corpulent rats with depressed levels of dopamine in very young or old lean rats. The activity of monoamine oxidase may provide an indication of nonadrenergic activity in tissue. The activity in the heart increased with age and was higher in the corpulent rats than in the lean at all ages. Activity in aorta was independent of age or genotype. Long term treatment with 6-hydroxydopamine caused marked depletion of norepinephrine in the heart with only a slight decrease in brain concentration. There were no effects on the hyperlipidemia or hyperinsulinemia that are strongly associated with vascular and myocardial disease. The myocardial lesion frequency in corpulent rats was not altered by the chemical sympathectomy. The results suggest that norepinephrine and the sympathetic nervous system are probably not involved in the generation of the myocardial lesions or metabolic abnormalities in this strain of rat. 相似文献
62.
Susan M Abdel-Rahman Nasreen Talib Ada Solidar Amy Jo Nopper Gerald J Wyckoff 《Medical mycology》2008,46(3):217-223
Trichophyton tonsurans infections occur in various host populations, on various body sites and with varying degrees of inflammation. This investigation was undertaken to determine whether fungal factors could explain the degree of severity in clinical symptomatology among infected children. Otherwise healthy children (n=54) presenting with tinea capitis were enrolled in this study. A thorough history was performed, the extent and severity of infection graded and a fungal specimen collected from each child. Strain type was determined by genotyping for 11 sequence variations in the rDNA and ALP1 loci. Secreted protease activity was quantitated after 5 days of growth in aqueous medium. Forty participants were evaluable. Infection duration ranged from 1 day to 3 years and clinical severity score (CSS) from 4-19. Seventeen unique fungal genotypes were present. Keratinase, collagenase and elastase activity varied 32.7-fold, 64.9-fold and 303.3-fold, respectively. A significant association was observed between genotype and disease severity with the rDNA sequence variations accounting for over 50% of the variation observed in CSS (r2=0.539; P<0.001). Phylogenetic analyses appear to suggest that the ancestral strain types of T. tonsurans cause more severe disease. These observations are consistent with reports that recently diverge anthropophilies are associated with diminished inflammatory involvement. 相似文献
63.
Goodman William Downing Amy Allsop Matthew Munro Julie Taylor Claire Hubbard Gill Beeken Rebecca J. 《Quality of life research》2022,31(8):2435-2444
Quality of Life Research - Quality of life can be negatively impacted by the formation of a stoma and is influenced by a number of factors. Research to date treats people with a stoma as a... 相似文献
64.
Egede Leonard E. Walker Rebekah J. Dawson Aprill Z. Zosel Amy Bhandari Sanjay Nagavally Sneha Martin Ian Frank Michael 《Quality of life research》2022,31(8):2387-2396
Quality of Life Research - This study aimed to investigate changes over time in quality of life, perceived stress, and serious psychological distress for individuals diagnosed with COVID-19 in an... 相似文献
65.
Journal of Public Health - The present study aimed to examine the effects of primary social factors on the smoking behaviors according to the smoking stages—initiation and... 相似文献
66.
Harrell Taylor Howell Elizabeth A. Balbierz Amy Guel Luz Pena Juan Janevic Teresa Gorbenko Ksenia 《Maternal and child health journal》2022,26(4):913-922
Maternal and Child Health Journal - The purpose of this study was to explore the postpartum experiences of publicly-insured women of color, and identify how postpartum care can be improved to... 相似文献
67.
68.
Background: Diet has been associated with poor glycemic control in diabetes. Few studies have examined this association in people with type 1 diabetes (T1D), who are at a higher risk for cardiovascular disease than people without diabetes. Methods: We report data from cross-sectional and longitudinal analyses from a coronary artery calcification in type 1 diabetes (CACTI) study (n = 1257; T1D: n = 568; non-diabetic controls: n = 689) collected between the years 2000 and 2002. Participants completed a validated food frequency questionnaire, a physical examination, and biochemical analyses. Dietary patterns based on variations in food group intake were created with principal components analysis. Linear regression was used to examine the associations of dietary patterns, macronutrients, and food groups with HbA1c in a model adjusted for relevant covariates and stratified by diabetes status. Results: Three dietary patterns were identified: “fruits, veggies, meats, cereal”, “baked desserts” and “convenience foods and alcohol” patterns. At baseline, a higher intake of the “baked dessert” pattern was significantly associated with higher HbA1c in T1D at baseline as well at year 6 of the study when adjusted for age, sex, BMI, total calories, and diabetes duration. No such associations were observed in the case of non-diabetic controls. Dietary saturated fats and animal fats were also positively associated with HbA1c in adults with T1D at baseline and/or at year 6. Conclusions: The habitual intake of a dietary pattern that is characterized by an increased intake of added sugar and saturated fats, such as in baked desserts, may increase risks of poor glycemic control in T1D. 相似文献
69.
Allison Durkin Patricia Anne Sta Maria Brandon Willmore Amy Kapczynski 《Health and human rights》2021,23(1):129
Human rights frameworks afford everyone the right to health and the right to enjoy the benefits of scientific progress and its applications. Both come together to create state obligations to ensure access to medicines and other health technologies. Though the impact of patents on access to high-quality, affordable medicines and health technologies has been well described, there has been little attention to the impact of trade secrecy law in this context. In this paper, we describe how trade secrecy protection comes into conflict with access to medicines—for example, by preventing researchers from accessing clinical trial data, undermining the scale-up of manufacturing in pandemics, and deterring whistleblowers from reporting industry misconduct. The paper proposes measures to diminish the conflict between trade secrecy and health that are consistent with international law and will advance health without undermining innovation. 相似文献
70.
Laura E. Zweifler Amy J. Koh Stephanie Daignault-Newton Laurie K. McCauley 《Journal of bone and mineral research》2021,36(10):1979-1998
Parathyroid hormone (PTH) is produced by the parathyroid glands in response to low serum calcium concentrations where it targets bones, kidneys, and indirectly, intestines. The N-terminus of PTH has been investigated for decades for its ability to stimulate bone formation when administered intermittently (iPTH) and is used clinically as an effective anabolic agent for the treatment of osteoporosis. Despite great interest in iPTH and its clinical use, the mechanisms of PTH action remain complicated and not fully defined. More than 70 gene targets in more than 90 murine models have been utilized to better understand PTH anabolic actions. Because murine studies utilized wild-type mice as positive controls, a variety of variables were analyzed to better understand the optimal conditions under which iPTH functions. The greatest responses to iPTH were in male mice, with treatment starting later than 12 weeks of age, a treatment duration lasting 5–6 weeks, and a PTH dose of 30–60 μg/kg/day. This comprehensive study also evaluated these genetic models relative to the bone formative actions with a primary focus on the trabecular compartment revealing trends in critical genes and gene families relevant for PTH anabolic actions. The summation of these data revealed the gene deletions with the greatest increase in trabecular bone volume in response to iPTH. These included PTH and 1-α-hydroxylase (Pth;1α(OH)ase, 62-fold), amphiregulin (Areg, 15.8-fold), and PTH related protein (Pthrp, 10.2-fold). The deletions with the greatest inhibition of the anabolic response include deletions of: proteoglycan 4 (Prg4, −9.7-fold), low-density lipoprotein receptor-related protein 6 (Lrp6, 1.3-fold), and low-density lipoprotein receptor-related protein 5 (Lrp5, −1.0-fold). Anabolic actions of iPTH were broadly affected via multiple and diverse genes. This data provides critical insight for future research and development, as well as application to human therapeutics. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献