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排序方式: 共有757条查询结果,搜索用时 31 毫秒
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Activation of bone morphogenetic protein/Smad signaling in bronchial epithelial cells during airway inflammation 总被引:8,自引:0,他引:8
Rosendahl A Pardali E Speletas M Ten Dijke P Heldin CH Sideras P 《American journal of respiratory cell and molecular biology》2002,27(2):160-169
Bone morphogenetic proteins (BMPs) are pleiotropic secreted proteins, structurally related to transforming growth factor (TGF)-beta and activins. BMPs play pivotal roles in the regulation of embryonic lung development and branching of airways and have recently been considered to influence inflammatory processes in adults due to their chemotactic activity on fibroblasts, myocytes, and inflammatory cells. In this study, we have investigated the possible involvement of BMPs in a model of experimental allergic-airway inflammation in situ using antibodies that detect activated Smad proteins, and have monitored the modulation of BMP ligands during the inflammatory response. Inflamed bronchial epithelial cells and a few scattered alveolar cells expressed levels of phosphorylated Smad1 (pSmad1/5), indicative of active BMP/Smad signaling. This was in contrast to healthy epithelium, which was devoid of immunoreactivity. A mechanistic explanation for increased pSmad1/5 staining during inflammation was provided by the upregulated expression of all the BMP type I receptors, i.e., activin receptor-like kinase (ALK)2, ALK3, and ALK6, in the inflamed bronchial epithelial cells. Furthermore, the mRNA and protein profiles for BMP ligands were significantly altered during airway inflammation with induction of BMP2, BMP4, and BMP6, and downregulation of BMP5 and BMP7. Collectively, our data demonstrate for the first time active BMP/Smad signaling during airway inflammation in bronchial epithelial cells and thus raise the possibility that BMPs could play a determining role in respiratory pathophysiology. 相似文献
4.
Lavanya Yohanathan Cristina C. Campioli Omar Y. Mousa Kymberly Watt Daniel Z. P. Friedman Vijay Shah Resham Ramkissoon Alexander S. Hines Patrick S. Kamath Raymund R. Razonable Andrew D. Badley Erin S. DeMartino Michael J. Joyner Rondell Graham Paschalis Vergidis Doug A. Simonetto William Sanchez Timucin Taner Julie K. Heimbach Elena Beam Michael D. Leise 《American journal of transplantation》2021,21(8):2890-2894
Current guidelines recommend deferring liver transplantation (LT) in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection until clinical improvement occurs and two PCR tests collected at least 24 hours apart are negative. We report a case of an 18-year-old, previously healthy African-American woman diagnosed with COVID-19, who presents with acute liver failure (ALF) requiring urgent LT in the context of SARS-CoV-2 polymerase chain reaction (PCR) positivity. The patient was thought to have acute Wilsonian crisis on the basis of hemolytic anemia, alkaline phosphatase:bilirubin ratio <4, AST:ALT ratio >2.2, elevated serum copper, and low uric acid, although an unusual presentation of COVID-19 causing ALF could not be excluded. After meeting criteria for status 1a listing, the patient underwent successful LT, despite ongoing SARS-CoV-2 PCR positivity. Remdesivir was given immediately posttransplant, and mycophenolate mofetil was withheld initially and the SARS-CoV-2 PCR test eventually became negative. Three months following transplantation, the patient has made a near-complete recovery. This case highlights that COVID-19 with SARS-CoV-2 PCR positivity may not be an absolute contraindication for transplantation in ALF. Criteria for patient selection and timing of LT amid the COVID-19 pandemic need to be validated in future studies. 相似文献
5.
Wilk JB Premkumar S Nicolaou M Myers RH Maher NE Harmon MD Farrer LA DeStefano AL Cupples LA Couropmitree NN 《Genetic epidemiology》1999,17(Z1):S761-S766
Linkage analysis was performed on the GAW11 Problem 2 data set using stratification to explore the effects of the environmental risk factors and the differences between mild and severe phenotypes. Analysis of the four study populations stratified by the two risk factors identified regions on chromosomes 3 and 5 with significant evidence for linkage. Other loci were sought by removing families consistent with linkage to the chromosome 3 locus. Our studies identified a locus on chromosome 3 (markers 43-46) associated with the mild phenotype in the presence of risk factor 1 and with the severe phenotype independent of risk factor 1. This suggests that distinct allelic variants at the chromosome 3 locus may cause different forms of disease. The locus identified on chromosome 5 (markers 36-39) was linked to the severe phenotype, but exposure to factor 1 or 2 may have a protective effect. The regions on chromosomes 3 and 5 appeared to have independent roles in disease etiology. Evidence for two loci on chromosome 1 linked to the mild form was found. The methods successfully identified linkages and interaction consistent with the generating model. 相似文献
6.
Nicolaou M Premkumar S DeStefano AL Farrer LA Cupples LA 《Genetic epidemiology》1999,17(Z1):S679-S684
Knowing the answers, we used the GAW11 data set to compare the power and efficiency of discordant versus concordant affected sib pairs for qualitative traits at different levels of penetrance. Samples of 200 concordant sib pairs outperformed discordant sib pairs for low penetrance (40%) and 70% penetrance models while at 90% penetrance they performed equally well. Increasing the sample size of discordant sib pairs to twice that of concordant pairs was not enough to reach the power of concordant sib pairs at the 40% and 70% penetrance models. For low penetrance using a combination of concordant and discordant sib pairs resulted in higher power than using discordant sib pairs alone. At 90% penetrance, the power of concordant and discordant sib pairs was similar in the region close to the gene while concordant sib pairs performed better at locations further from the gene. 相似文献
7.
Kenyon SH Waterfield CJ Asker DS Kudo M Moss DW Bates TE Nicolaou A Gibbons WA Timbrell JA 《Biochemical pharmacology》1999,57(11):1311-1319
The effect of the industrial chemical, hydrazine (4-12 mM), on methionine synthase (EC 2.1.1.13) activity and levels of the sulphur amino acids homocysteine, cysteine, and taurine as well as GSH were investigated in vitro in isolated rat hepatocyte suspensions and monolayers in order to explain some of the adverse in vivo effects of hydrazine. None of the concentrations of hydrazine were overtly cytotoxic in hepatocyte suspensions (measured as lactate dehydrogenase [LDH] leakage) after 3 hr. However, after 24 hr in culture cells treated with 12 mM, hydrazine showed a significant increase in LDH leakage. Methionine synthase activity was reduced by hydrazine (8 and 12 mM) in suspensions (by 45 and 55%, after 3 hr) and monolayers (12 mM; 65-80% after 24 hr). This was not due to nitric oxide production and the inhibitor of nitric oxide synthase, Nomega-nitro-L-arginine, failed to protect against the hydrazine-induced loss of ATP and GSH and the reduction in urea synthesis at 24 hr. Homocysteine export was increased by 6 mM hydrazine, and total taurine content of treated cells was increased by 12 mM hydrazine. Thus, hydrazine was found to have several important and possibly deleterious effects on some parts of the sulphur amino acid pathway. 相似文献
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As the market place becomes increasingly competitive, marketing has been more aggressively undertaken by private business, and more recently, by proprietary and not for profit hospitals and other human service organizations. This article describes the efforts of an urban, publicly supported, multi-provider mental health system to develop an assertive, positive marketing stance. Following a brief historical development, the authors describe the current public relations campaign and some of the specific techniques used. 相似文献
9.
F. A. Jenner C. R. Lee C. Paschalis S. E. Hill L. Burkinshaw G. Jennings 《Psychopharmacology》1983,81(4):301-309
Five patients suffering from periodic affective disorders with short mood-cycles were treated with rubidium chloride, producing peak erythrocyte concentrations between 9 and 13 mmol/l. Loading with rubidium was associated with decreased total body potassium, but red-cell potassium was unchanged. Regular mood-cycling was disturbed, together with the associated body-weight changes. There was a slight extracellular "metabolic" acidosis. Electrolyte concentrations fluctuate abnormally in these patients, and two muscle biopsy specimens had very low potassium contents. 相似文献
10.
Benjamin Movsas Charles Scott Corey Langer Maria Werner-Wasik Nicos Nicolaou Ritsuko Komaki Mitchell Machtay Colum Smith Rita Axelrod Linda Sarna Todd Wasserman Roger Byhardt 《Journal of clinical oncology》2005,23(10):2145-2154
PURPOSE: To test the ability of the cytoprotectant, amifostine, to reduce chemoradiotherapy-induced esophagitis and evaluate its influence on quality of life (QOL) and swallowing symptoms. PATIENTS AND METHODS: A total of 243 patients with stage II to IIIA/B non-small-cell lung cancer received induction paclitaxel 225 mg/m(2) intravenously (IV) days 1 and 22 and carboplatin area under the curve (AUC) days 1 and 22, followed by concurrent weekly paclitaxel (50 mg/m(2) IV) and carboplatin (AUC 2), and hyperfractionated radiation therapy (69.6 Gy at 1.2 Gy bid). Patients were randomly assigned at registration to amifostine (AM) 500 mg IV four times per week or no AM during chemoradiotherapy. Beyond standard toxicity end points, physician dysphagia logs (PDLs), daily patient swallowing diaries, and QOL (EORTC QLQ-C30/LC-13) were also collected. Swallowing AUC analyses were calculated from patient diaries and PDLs. RESULTS: A total of 120 patients were randomly assigned to receive AM, and 122, to receive no AM (one patient was ineligible); 72% received AM per protocol or with a minor deviation. AM was associated with higher rates of acute nausea (P = .03), vomiting (P = .007), cardiovascular toxicity (P = .0001), and infection or febrile neutropenia (P = .03). The rate of >/= grade 3 esophagitis was 30% with AM versus 34% without AM (P = .9). Patient diaries demonstrated lower swallowing dysfunction AUC with amifostine (z test P = .025). QOL was not significantly different between the two arms, except for pain, which showed more clinically meaningful improvement and less deterioration at 6 weeks follow-up (v pretreatment) in the AM arm (P = .003). The median survival rates for both arms were comparable (AM, 17.3 v no AM, 17.9 months; P = .87). CONCLUSION: AM did not significantly reduce esophagitis >/= grade 3 in patients receiving hyperfractionated radiation and chemotherapy. However, patient self-assessments suggested a possible advantage to AM that is being explored with modified dosing route strategies. 相似文献