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951.
Hepatic apoptosis and proliferation in male and female rats fed alcohol: role of cytokines 总被引:7,自引:1,他引:7
Colantoni A Idilman R De Maria N La Paglia N Belmonte J Wezeman F Emanuele N Van Thiel DH Kovacs EJ Emanuele MA 《Alcoholism, clinical and experimental research》2003,27(7):1184-1189
Background: The female liver is more sensitive to the toxic effect of chronic alcohol intake than the male liver. The aim of the study was to compare the influence of gender and sex hormonal status on apoptosis and cell proliferation following chronic ethanol intake.
Methods: Male and female rats were pair fed for 8 weeks a liquid diet containing 36% of their total daily calories as ethanol (ETOH group) or sucrose (control group). Liver samples were analyzed for apoptosis and hepatocyte proliferation by immunohistochemistry. The hepatic production of factors able to influence cell death and proliferation, such as tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6) were determined.
Results: In both male and female rats, ethanol intake promoted apoptosis in the liver. This effect of ethanol was more evident in female than male rat livers. Hepatic TNFα levels, which promote apoptosis, are significantly more elevated in female than in male livers. Hepatic IL-6 production, which promotes hepatocyte proliferation, was induced by ethanol only in males, but not female animals.
Conclusion: This observed difference in cytokine responses may contribute to the enhanced sensitivity of female liver to EtOH-induced injury. 相似文献
Methods: Male and female rats were pair fed for 8 weeks a liquid diet containing 36% of their total daily calories as ethanol (ETOH group) or sucrose (control group). Liver samples were analyzed for apoptosis and hepatocyte proliferation by immunohistochemistry. The hepatic production of factors able to influence cell death and proliferation, such as tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6) were determined.
Results: In both male and female rats, ethanol intake promoted apoptosis in the liver. This effect of ethanol was more evident in female than male rat livers. Hepatic TNFα levels, which promote apoptosis, are significantly more elevated in female than in male livers. Hepatic IL-6 production, which promotes hepatocyte proliferation, was induced by ethanol only in males, but not female animals.
Conclusion: This observed difference in cytokine responses may contribute to the enhanced sensitivity of female liver to EtOH-induced injury. 相似文献
952.
Dial EJ Hall LR Romero JJ Lechago J Fox JG Lichtenberger LM 《Digestive diseases and sciences》2000,45(7):1308-1314
Altered gastrin expression associated with Helicobacter pylori infection may contribute to the pathogenesis of peptic ulcer disease or gastric cancer in man, but gastrin has not been investigated in a murine model of Helicobacter infection. C57BL/6 mice were inoculated with Helicobacter felis and examined after 4–21 weeks for G and D cell numbers, antral gastrin and somatostatin mRNA, and luminal pH. In H. felis-infected mice, gastrin mRNA declined at four and six weeks after infection to 57% and 23%, respectively, of uninfected control values. Concurrently, somatostatin mRNA showed no change at four weeks and a modest 25% decrease at six weeks after infection. Similar reductions were noted in G and D cell numbers, resulting in a decrease in the G/D cell ratio after mice were infected with H. felis. Infected animals also showed a loss of parietal and chief cells, and an increased gastric pH. H. felis infection in C57BL/6 mice leads to an early suppression of G cell number and gastrin mRNA. These changes precede an alteration in somatostatin cell number and mRNA and, coupled with reductions in parietal and chief cells, may contribute both to severe impairment of gastric acid output and the potential for carcinogenic processes. 相似文献
953.
Ludy MJ Hendricks K Houser R Chetchotisakd P Mootsikapun P Anunnatsiri S Price E Wanke CA 《The American journal of tropical medicine and hygiene》2005,73(4):815-819
A cross-sectional study of 77 patients infected with human immunodeficiency virus (HIV) in Khon Kaen, Thailand examined association of nutritional status with active opportunistic infections (AOIs)/HIV status and assessed degree of correlation between bioelectrical impedance analysis (BIA) and anthropometry. Many patients (41.3%) were malnourished using World Health Organization criteria for underweight, and malnutrition was associated with AOI status. Unconditional odds ratios (P < 0.05) for AOI as opposed to no AOI were 4.57 for underweight, 9.87 for severe underweight, 2.55 for triceps < 10th percentile, and 5.22 for mid-arm circumference < 10th percentile. Body fat composition from BIA, anthropometry, and body mass index were moderate to highly correlated (P < 0.001), with the highest correlation between BIA and subscapular skinfold (r = 0.86) and the lowest between BIA and triceps skinfold (r = 0.54). Insights were gained about relative value of using various measurements to assess nutritional status of HIV-infected populations. 相似文献
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Brandon P. Verdoorn MD Tamara K. Evans BS Gregory J. Hanson MD Yi Zhu PhD Larissa G. P. Langhi Prata PhD Robert J. Pignolo MD PhD Elizabeth J. Atkinson MS Erin O. Wissler-Gerdes MA George A. Kuchel MD Joan B. Mannick MD Stephen B. Kritchevsky PhD Sundeep Khosla MD Stacey A. Rizza MD Jeremy D. Walston MD Nicolas Musi MD Lewis A. Lipsitz MD Douglas P. Kiel MD Raymond Yung MB ChB Nathan K. LeBrasseur PhD Ravinder J. Singh PhD Teresa McCarthy MD MS Michael A. Puskarich MD Laura J. Niedernhofer MD PhD Paul D. Robbins PhD Matthew Sorenson JD MA Tamara Tchkonia PhD James L. Kirkland MD PhD 《Journal of the American Geriatrics Society》2021,69(11):3023-3033
The burden of senescent cells (SnCs), which do not divide but are metabolically active and resistant to death by apoptosis, is increased in older adults and those with chronic diseases. These individuals are also at the greatest risk for morbidity and mortality from SARS-CoV-2 infection. SARS-CoV-2 complications include cytokine storm and multiorgan failure mediated by the same factors as often produced by SnCs through their senescence-associated secretory phenotype (SASP). The SASP can be amplified by infection-related pathogen-associated molecular profile factors. Senolytic agents, such as Fisetin, selectively eliminate SnCs and delay, prevent, or alleviate multiple disorders in aged experimental animals and animal models of human chronic diseases, including obesity, diabetes, and respiratory diseases. Senolytics are now in clinical trials for multiple conditions linked to SnCs, including frailty; obesity/diabetes; osteoporosis; and cardiovascular, kidney, and lung diseases, which are also risk factors for SARS-CoV-2 morbidity and mortality. A clinical trial is underway to test if senolytics decrease SARS-CoV-2 progression and morbidity in hospitalized older adults. We describe here a National Institutes of Health-funded, multicenter, placebo-controlled clinical trial of Fisetin for older adult skilled nursing facility (SNF) residents who have been, or become, SARS-CoV-2 rtPCR-positive, including the rationale for targeting fundamental aging mechanisms in such patients. We consider logistic challenges of conducting trials in long-term care settings in the SARS-CoV-2 era, including restricted access, consent procedures, methods for obtaining biospecimens and clinical data, staffing, investigational product administration issues, and potential solutions for these challenges. We propose developing a national network of SNFs engaged in interventional clinical trials. 相似文献
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