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991.
G J Poston R Saydjari J Lawrence R W Alexander C M Townsend J C Thompson 《Journal of gerontology》1990,45(6):B220-B225
We examined the effect of age on the adaptive capacity of small bowel mucosa following 60% enterectomy. Two groups of male Fischer 344 rats (3 mo old and 26 mo) underwent either a mid-small bowel transection and reanastomosis (control) or 60% proximal enterectomy beginning at the duodenojejunal junction. Rats were sacrificed at 5, 14, and 21 days after operation, and the mucosa was weighed and assayed for DNA, RNA, protein, and polyamine concentration and content. Ornithine decarboxylase activity was also measured in ileal mucosa at 5 days after surgery. Young rats had completed the adaptive hyperplastic response within 2 weeks after operation by all biochemical measurements; similar adaptation was not seen until 3 weeks after operation in the old rats. We conclude that although the capacity to achieve intestinal adaptation after enterectomy is preserved into old age in rats, this compensatory response is delayed. 相似文献
992.
Recombinant human granulocyte colony-stimulating factor (G-CSF) treatment has been shown to increase average neutrophil counts substantially in patients with childhood-onset cyclic neutropenia (or "cyclic hematopoiesis"), but not to eliminate the cyclic oscillations of neutrophil counts or those of other blood elements (monocytes, platelets, eosinophils, and reticulocytes) that are characteristic of this hematopoietic disorder. Indeed, oscillations of neutrophil counts are amplified during G-CSF treatment. We have compared the effects of recombinant granulocyte-macrophage-CSF (GM-CSF) with those of G-CSF in three patients with this disease (2 men and 1 woman, 17, 30, and 32 years of age). These patients were treated with GM-CSF (2.1 micrograms/kg/day, subcutaneously) for 6 weeks, preceded and followed by 6 to 13 weeks of detailed observation to document changes in the cyclic oscillations of blood neutrophils and other blood elements; two of the patients were subsequently treated with G-CSF (5.0 micrograms/kg/d, subcutaneously) and observed for comparable periods of time. Unlike G-CSF treatment, which increased average neutrophil counts more than 20-fold, GM-CSF increased neutrophil counts only modestly, from 1.6- to 3.9-fold, although eosinophilia of varying prominence was induced in each patient. However, at the same time, GM-CSF treatment dampened or eliminated the multilineage oscillations of circulating blood elements (neutrophils, monocytes, platelets, and/or reticulocytes) in each of the patients. In contrast, G-CSF treatment of the same patients markedly amplified the oscillations of neutrophil counts and caused the cycling of other blood elements (monocytes in particular) to become more distinct. These findings support the conclusion that the distinctive cycling of blood cell production in childhood-onset cyclic neutropenia results from abnormalities in the coordinate regulation of both GM-CSF-responsive, multipotential progenitor cells and G-CSF-responsive, lineage-restricted, neutrophil progenitors. 相似文献
993.
Bridges CB Lim W Hu-Primmer J Sims L Fukuda K Mak KH Rowe T Thompson WW Conn L Lu X Cox NJ Katz JM 《The Journal of infectious diseases》2002,185(8):1005-1010
In 1997, outbreaks of highly pathogenic influenza A (H5N1) among poultry coincided with 18 documented human cases of H5N1 illness. Although exposure to live poultry was associated with human illness, no cases were documented among poultry workers (PWs). To evaluate the potential for avian-to-human transmission of H5N1, a cohort study was conducted among 293 Hong Kong government workers (GWs) who participated in a poultry culling operation and among 1525 PWs. Paired serum samples collected from GWs and single serum samples collected from PWs were considered to be anti-H5 antibody positive if they were positive by both microneutralization and Western blot testing. Among GWs, 3% were seropositive, and 1 seroconversion was documented. Among PWs, approximately 10% had anti-H5 antibody. More-intensive poultry exposure, such as butchering and exposure to ill poultry, was associated with having anti-H5 antibody. These findings suggest an increased risk for avian influenza infection from occupational exposure. 相似文献
994.
Nancy Winnik Berland J. Kevin Thompson Patrick H. Linton 《The International journal of eating disorders》1986,5(3):569-574
The 40-item Eating Attitudes Jest, the 26-item Eating Attitudes Test, the Restrained Eating Inventory (El), and the Eating Disorders Inventory (EDI) were given to 81 women who were participating in an eating disorders study. The EAT-26 totals and the scores of the three factors were intercorrelated. The scores of the EAT-26 were also correlated with the scores of the EAT-40, and El, and the EDI. The EAT-26 correlated significantly with all three of its factors as well as with the EAT-40. These results suggest that the EAT-26 is a reliable and economical substitute for the EAT-40. The EAT-26 correlates highly with the eight subscales of the EDI and with the El, suggesting concurrent validity. 相似文献
995.
Meghann C. Ryan L. Elliot Hong Kathryn S. Hatch Si Gao Shuo Chen Krystl Haerian Jingtao Wang Eric L. Goldwaser Xiaoming Du Bhim M. Adhikari Heather Bruce Stephanie Hare Mark D. Kvarta Neda Jahanshad Thomas E. Nichols Paul M. Thompson Peter Kochunov 《Human brain mapping》2022,43(6):1997
Severe mental illnesses (SMI) including major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia spectrum disorder (SSD) elevate accelerated brain aging risks. Cardio‐metabolic disorders (CMD) are common comorbidities in SMI and negatively impact brain health. We validated a linear quantile regression index (QRI) approach against the machine learning “BrainAge” index in an independent SSD cohort (N = 206). We tested the direct and additive effects of SMI and CMD effects on accelerated brain aging in the N = 1,618 (604 M/1,014 F, average age = 63.53 ± 7.38) subjects with SMI and N = 11,849 (5,719 M/6,130 F; 64.42 ± 7.38) controls from the UK Biobank. Subjects were subdivided based on diagnostic status: SMI+/CMD+ (N = 665), SMI+/CMD− (N = 964), SMI−/CMD+ (N = 3,765), SMI−/CMD− (N = 8,083). SMI (F = 40.47, p = 2.06 × 10−10) and CMD (F = 24.69, p = 6.82 × 10−7) significantly, independently impacted whole‐brain QRI in SMI+. SSD had the largest effect (Cohen’s d = 1.42) then BD (d = 0.55), and MDD (d = 0.15). Hypertension had a significant effect on SMI+ (d = 0.19) and SMI− (d = 0.14). SMI effects were direct, independent of MD, and remained significant after correcting for effects of antipsychotic medications. Whole‐brain QRI was significantly (p < 10−16) associated with the volume of white matter hyperintensities (WMH). However, WMH did not show significant association with SMI and was driven by CMD, chiefly hypertension (p < 10−16). We used a simple and robust index, QRI, the demonstrate additive effect of SMI and CMD on accelerated brain aging. We showed a greater effect of psychiatric illnesses on QRI compared to cardio‐metabolic illness. Our findings suggest that subjects with SMI should be among the targets for interventions to protect against age‐related cognitive decline. 相似文献
996.
997.
The disease yellow fever was prevented by two live attenuated vaccines, strains 17D and French neurotropic vaccine (FNV), derived by serial passage of wild-type (WT) strains Asibi and French Viscerotropic virus (FVV), respectively. Both 17D and FNV displayed decreased genetic diversity and resistance to the antiviral Ribavirin compared to their WT parental strains, which are thought to contribute to their attenuated phenotypes. Subsequent studies found that only a few passages of WT strain FVV in HeLa cells resulted in an attenuated virus. In the current study, the genome sequence of FVV following five passages in HeLa cells (FVV HeLa p5) was determined through Next Generation Sequencing (NGS) with the aim to investigate the molecular basis of viral attenuation. It was found that WT FVV and FVV HeLa p5 virus differed by five amino acid substitutions: E-D155A, E-K331R, E-I412V, NS2A-T105A, and NS4B-V98I. Surprisingly, the genetic diversity and Ribavirin resistance of the FVV HeLa p5 virus were not statistically different to WT parent FVV. These findings suggest that while FVV HeLa p5 is attenuated, this is not dependent on a high-fidelity replication complex, characterized by reduced genetic diversity or increased Ribavirin stability, as seen with FNV and 17D vaccines. 相似文献
998.
Following the availability of highly effective direct-acting antivirals (DAAs) to treat hepatitis C infection, the uptake of treatment by people living with hepatitis C rose dramatically in high- and middle-income countries but has since declined. To achieve the World Health Organization’s (WHO) 2030 target to eliminate hepatitis C as a public health threat among people who inject drugs, an increase in testing and treatment is required, together with improved coverage of harm reduction interventions. The population that remains to be treated in high- and middle-income countries with high hepatitis C prevalence are among the most socially disadvantaged, including people who inject drugs and are involved in the criminal justice system, a group with disproportionate hepatitis C prevalence, compared with people in the wider community. Imprisonment provides an unrivalled opportunity for screening and treating large numbers of people for hepatitis C, who may not access mainstream health services in the community. Despite some implementation challenges, evidence of the efficacy, acceptability, and cost-effectiveness of in-prison hepatitis treatment programs is increasing worldwide, and evaluations of these programs have demonstrated the capacity for treating people in high numbers. In this Perspective we argue that the scale-up of hepatitis C prevention, testing, and treatment programs in prisons, along with the investigation of new and adapted approaches, is critical to achieving WHO elimination goals in many regions; the Australian experience is highlighted as a case example. We conclude by discussing opportunities to improve access to prevention, testing, and treatment for people in prison and other justice-involved populations, including harnessing the changed practices brought about by the COVID-19 pandemic. 相似文献
999.
S. J. Clearwater S.A. Wood N.R. Phillips S.M. Parkyn R. Van Ginkel K.J. Thompson 《Environmental toxicology》2014,29(5):487-502
Survival of juvenile freshwater mussels (Echyridella menziesii (Gray, 1843) formerly known as Hyridella menziesi) and crayfish (Paranephrops planifrons, White, 1842) decreased after four days exposure to microcystin‐containing cell‐free extracts (MCFE) of Microcystis sp. at concentrations typical of severe cyanobacterial blooms. Crayfish survival was 100, 80, and 50% in microcystin concentrations of 1339, 2426, and 11146 μg L?1 respectively, and shade‐ and shelter‐seeking behavior was negatively affected when concentrations were ≥2426 μg L?1. Mussel survival decreased to 92% and reburial rates decreased to 16% after exposure for 96 h to MCFE containing microcystins at concentrations of 5300 μg L?1. Crayfish survival was 100% when fed freeze‐dried Microcystis sp. incorporated into an artificial diet (6–100 μg microcystin kg?1 ww) at dietary doses from 0.03 to 0.55 μg g?1 body weight d?1 for 27 days. Specific growth rate was significantly lower in crayfish fed ≥0.15 μg g?1 body weight day?1 compared with controls, but not compared with a diet incorporating nontoxic cyanobacteria. Microcystins accumulated preferentially in crayfish hepatopancreas and mussel digesta as MCFE or dietary concentrations increased. These laboratory data indicate that, assuming dissolved oxygen concentrations remain adequate, and no simultaneous exposure to live Microcystis sp. cells, cell‐free microcystins will only be a significant stressor to juvenile crayfish and mussels in severe Microcystis sp. blooms. In contrast, crayfish were negatively affected by relatively low concentrations of microcystins in artificial diets compared with those measured locally in benthic cyanobacterial mats. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 487–502, 2014. 相似文献
1000.