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51.
The role of brain monoamines (5-HT, NA and DA) in the secretion of adrenocorticotrophic hormone (ACTH) was studied in view of contradictory reports. Plasma corticosterone levels and the rate of synthesis of corticosterone in vitro by the adrenal gland were estimated in albino rats and have been taken as the index of ACTH activity. These estimations were done in unstressed and stressed, and in untreated and treated rats. Drugs were administered intracerebroventricularly to the rats to cause selective degeneration of tryptaminergic, noradrenergic or dopaminergic neurons. The results show that plasma corticosterone levels and the rate of synthesis of corticosterone were significantly decreased after selective degeneration of tryptaminergic neurons in unstressed rats. After selective degeneration of either tryptaminergic or noradrenergic neurons, the acute increase in the plasma corticosterone levels and rate of synthesis of corticosterone in vitro by adrenal glands in stressed rats were significantly inhibited. These results have been interpreted to suggest that the central tonic control on adrenal glands may be 5-HT mediated and that during stress ACTH secretion may be both 5-HT and NA mediated. DA does not seem to have significant role in the regulation of ACTH secretion. 相似文献
52.
Intermittent outpatient ultrafiltration for the treatment of severe refractory congestive heart failure 总被引:2,自引:0,他引:2
Sheppard R Panyon J Pohwani AL Kapoor A Macgowan G McNamara D Mathier M Johnston JR Murali S 《Journal of cardiac failure》2004,10(5):380-383
BACKGROUND: Patients with severe congestive heart failure (CHF) become refractory to conventional medical therapy, leading to recurrent rehospitalizations. We examined the impact of intermittent outpatient ultrafiltration (UF), using either peritoneal dialysis or hemofiltration, on long-term clinical outcomes in patients with refractory CHF. METHODS AND RESULTS: We analyzed clinical and hemodynamic data in 19 consecutive patients with refractory CHF who received intermittent outpatient UF for at least 1 year between July 1998 and November 2002. The mean left ventricular ejection fraction of all 19 patients was 30.2 +/- 19.0%. All patients (100.0%) were New York Heart Association (NYHA) class IV. Only 5 patients (26.3%) received peritoneal dialysis; the remaining 14 (73.7%) received hemofiltration. There were 6 patients with a normal left ventricular ejection fraction (45%). After UF was started, the number of patients that were considered inotrope-dependent was reduced from 86.4% to 36.8% (P < .005). Compared with the year before UF was initiated, the number of CHF hospitalizations during follow-up was reduced from 2.6 to 0.3 (P < .005), and the NYHA class was improved from 4 to 3.1 (P < .005). Among all patients, 2 deaths were related to complications of UF, and cumulative 1-year survival was 63.2%. CONCLUSION: Our study suggests that UF is a safe, feasible therapy, but it needs further evaluation in carefully designed, prospective, randomized clinical trials. UF has the potential for offering another important therapeutic option for patients with severe and refractory CHF. 相似文献
53.
Stephan Sauer Sandra S. Burkett Mark Lewandoski Amar J. S. Klar 《Chromosome research》2013,21(3):311-328
Sister chromatids contain identical DNA sequence but are chiral with respect to both their helical handedness and their replication history. Emerging evidence from various model organisms suggests that certain stem cells segregate sister chromatids nonrandomly to either maintain genome integrity or to bias cellular differentiation in asymmetric cell divisions. Conventional methods for tracing of old vs. newly synthesized DNA strands generally lack resolution for individual chromosomes and employ halogenated thymidine analogs with profound cytotoxic effects on rapidly dividing cells. Here, we present a modified chromosome orientation fluorescence in situ hybridization (CO-FISH) assay, where identification of individual chromosomes and their replication history is achieved in subsequent hybridization steps with chromosome-specific DNA probes and PNA telomere probes. Importantly, we tackle the issue of BrdU cytotoxicity and show that our method is compatible with normal mouse ES cell biology, unlike a recently published related protocol. Results from our CO-FISH assay show that mitotic segregation of mouse chromosome 7 is random in ES cells, which contrasts previously published results from our laboratory and settles a controversy. Our straightforward protocol represents a useful resource for future studies on chromatid segregation patterns of in vitro-cultured cells from distinct model organisms. 相似文献
54.
The base complementarity feature (Watson and Crick in Nature 171(4356):737–738, 1953) and the rule of semi-conservative mode of DNA replication (Messelson and Stahl in Proc Natl Acad Sci U S A 44:671–682, 1958) dictate that two identical replicas of the parental chromosome are produced during replication. In principle, the inherent strand sequence differences could generate nonequivalent daughter chromosome replicas if one of the two strands were epigenetically imprinted during replication to effect silencing/expression of developmentally important genes. Indeed, inheritance of such a strand- and site-specific imprint confers developmental asymmetry to fission yeast sister cells by a phenomenon called mating/cell-type switching. Curiously, location of DNA strands with respect to each other at the centromere is fixed, and as a result, their selected segregation to specific sister chromatid copies occurs in eukaryotic cells. The yeast system provides a unique opportunity to determine the significance of such biased strand distribution to sister chromatids. We determined whether the cylindrical-shaped yeast cell distributes the specific chromosomal strand to the same cellular pole in successive cycles of cell division. By observing the pattern of recurrent mating-type switching in progenies of individual cells by microscopic analyses, we found that chromosome 2 strands are distributed by the random mode in successive cell divisions. We also exploited unusual “hotspot” recombination features of this system to investigate whether there is selective segregation of strands such that oldest Watson-containing strands co-segregate in the diploid cell at mitosis. Our data suggests that chromosome 2 strands are segregated independently to those of the homologous chromosome. 相似文献
55.
Yashwant Patidar Chandan Kumar Pal Amar Mukund Guresh Kumar Shiv Kumar Sarin 《The British journal of radiology》2021,94(1120)
Objective:Comparing the efficacy, safety and outcome of percutaneous intrervention for Budd-Chiari Syndrome (BCS) patients with bilirubin less than 3 and 3–6 mg dl−1.Methods and materials:188 BCS patients having serum bilirubin ≤6 mg dl−1 and underwent percutaneous interventions were divided into two groups based on bilirubin level: 151 patients having bilirubin <3 mg dl−1 were included in Group 1; and 37 patients having bilirubin 3–6 mg dl−1 were included in Group 2. Both group were compare for technical success (successful recanalization of hepatic venous stenosis or creation of portocaval shunt with post-procedure gradient ≤5 mm of Hg), Safety (procedure-related mortality/morbidity or patient required transplantation) and outcome (resolution of clinical symptoms and survival).Results:Technical success was 94.7% in Group 1–89.1% in Group 2 with overall success rate was 93.6%. No significant differences observed between the two groups in regards to procedure related complication. Overall transplant-free survival at 1 and 5 years after intervention in both groups was 96.3 and 91.2% respectively. 1-year and 5-year survivals in Group 1 was 96.7%, and 93.1%, whereas Group 2 was 94.6 and 90.1% with no statically significantly difference between the two groups (p = 0.59). Percutaneous intervention results are good in patients having bilirubin up to 6 mg dl−1, i.e. mild to moderate liver dysfunctions.Conclusion:Technical success, survival and outcome of percutaneous intervention in BCS patients having serum bilirubin 3–6 mg dl−1 was comparable to patients having bilirubin level <3 mg dl−1.Advances in knowledge:Percutaneous intervention treatment is suitable for treatment for symptomatic BCS patients having bilirubin up to 6 mg dl−1. 相似文献
56.
Douglas A. Luke Bobbi J. Carothers Amar Dhand Ryan A. Bell Sarah Moreland‐Russell Cathy C. Sarli Bradley A. Evanoff 《CTS Clinical and Translational Science》2015,8(2):143-149
The importance of transdisciplinary collaboration is growing, though not much is known about how to measure collaboration patterns. The purpose of this paper is to present multiple ways of mapping and evaluating the growth of cross‐disciplinary partnerships over time. Social network analysis was used to examine the impact of a Clinical and Translational Science Award (CTSA) on collaboration patterns. Grant submissions from 2007 through 2010 and publications from 2007 through 2011 of Institute of Clinical and Translational Sciences (ICTS) members were examined. A Cohort Model examining the first‐year ICTS members demonstrated an overall increase in collaborations on grants and publications, as well as an increase in cross‐discipline collaboration as compared to within‐discipline. A Growth Model that included additional members over time demonstrated the same pattern for grant submissions, but a decrease in cross‐discipline collaboration as compared to within‐discipline collaboration for publications. ICTS members generally became more cross‐disciplinary in their collaborations during the CTSA. The exception of publications for the Growth Model may be due to the time lag between funding and publication, as well as pressure for younger scientists to publish in their own fields. Network analysis serves as a valuable tool for evaluating changes in scientific collaboration. 相似文献
57.
Saima Naz Mohsin Saqib Mahmood Ali Amar Farkhanda Ghafoor Syed Mohsin Raza Mahjabeen Saleem 《The American journal of tropical medicine and hygiene》2015,93(4):691-696
Dengue illness has been a major health concern in Pakistan during the last decade. Dengue infection can result in a spectrum of clinically distinct outcomes, ranging from asymptomatic infection to potentially life-threatening forms of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). A single-nucleotide polymorphism in FcγRIIa (rs1801274) results in altered affinity of the receptor for different subclasses of immunoglobulin G, and is a key player in determining the susceptibility to or protection from severe clinical infection of dengue. In this study, we analyzed the allelic and genotypic distribution of rs1801274 in subjects of Pakistani origin with subclinical dengue infection (n = 40), dengue fever (DF) (n = 40), and DHF/DSS (n = 30). We found that HH homozygotes and heterozygotes were significantly more likely to develop clinical dengue (odds ratio [OR] = 3.21, 95% confidence interval [CI] = 1.29–7.97, P = 0.009), either DF (OR = 2.82, 95% CI = 1.00–7.97, P = 0.045) or DHF/DSS (OR = 3.90, 95% CI = 1.13–13.07, P = 0.024) than the asymptomatic dengue infection. Results of allelic distribution comparisons and logistic regression analysis also supported the same relationship. The results suggest complex nature of interacting factors in determining the course for severe dengue illness. 相似文献
58.
Effect of a genomic classifier test on clinical practice decisions for patients with high‐risk prostate cancer after surgery
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59.
Antonia Scobie Sanch Kanagarajah Ross J. Harris Lisa Byrne Corinne Amar Kathie Grant Gauri Godbole 《The Journal of infection》2019,78(3):208-214