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81.
Péter Várnai Gábor L. Petheö Judit K. Makara András Spät 《Pflügers Archiv : European journal of physiology》1998,435(3):429-431
Elevation of extracellular potassium concentration by as little as some tenth of mM activates rat adrenal glomerulosa cells.
In the present study some factors responsible for this high K+ sensitivity were examined. Using whole-cell voltage-clamp technique we found that both T-type and L-type voltage-dependent
Ca2+ channels have very low threshold potential (–71 and –58 mV, resp.). By means of patch-clamp technique combined with single-cell
fluorimetry we also provided evidence that the activation of Igl, a K+-activated inward rectifying current is associated with Ca2+ influx. Both the low activation threshold of voltage-dependent Ca2+ channels and the function of Igl contribute to the exceptional K+ sensitivity of the glomerulosa cells.
Received: 30 September 1997 / Accepted: 4 November 1997 相似文献
82.
The thermal responses of neonates during a cool acclimation period were studied with regard to sleep stages. Sleep stages, body temperatures and metabolic rate (VO2) were studied for seven neonates nursed in incubators and exposed to a cool temperature (thermoneutrality minus 2 degrees C) for 75 h. Each recording session lasted 3 h in the morning: firstly under thermoneutral baseline conditions, then during the first and last 3-h periods of the cool acclimation and finally during the last 3 h of a 24-h recovery period. Sleep structure was modified during the initial hours of cool exposure: the percentage of active sleep increased (AS: +13%, P = 0.028) at the expense of quiet sleep (QS: -11%, P = 0.043). This alteration in sleep structure persisted at the end of the acclimation period. Metabolic heat production only increased in the later period of cool acclimation. Throughout the cool exposure, VO2 increased more (P = 0.040) in QS (+33%) than in AS (+20%) so that by the end of the cool period, VO2 levels were similar in both sleep stages. During cool acclimation, the maintenance of homeothermy is related not only to a change in sleep organization but also to modifications in the thermoregulatory processes in both sleep stages. Considering the importance of AS/QS patterns in the neurobehavioral development of neonates, the present results could have clinical implications for the thermal management of neonates. 相似文献
83.
Navin Wadehra Sherif Farag Brian Bolwell Patrick Elder Sam Penza Matt Kalaycio Belinda Avalos Brad Pohlman Guido Marcucci Ronald Sobecks Thomas Lin Steven Andrèsen Edward Copelan 《Biology of blood and marrow transplantation》2006,12(12):1343-1349
Busulfan (Bu)-based preparative regimens have not been extensively investigated in Hodgkin disease (HD). The purposes of this study were to investigate the toxicity and efficacy of a novel preparative regimen of Bu 14 mg/kg, etoposide 50-60 mg/kg, and cyclophosphamide 120 mg/kg in patients with primary refractory and relapsed HD. One hundred twenty-seven patients with a median age of 33 years (range, 14-67 years) underwent transplantation. The regimen was well tolerated, with 5.5% treatment-related mortality at 100 days after transplantation. With a median follow up of 6.7 years, the 5-year progression-free survival was 48 +/- 5%, and the 5-year overall survival was 51 +/- 5%. A Cox proportional hazards model identified refractory disease at time of transplantation as the only significant factor affecting relapse and overall survival, whereas disease bulk >10 cm affected overall survival. Five patients died between 5.3 and 9.3 years of late complications, including secondary myelodysplasia or acute myeloid leukemia, secondary solid malignancies, and pulmonary toxicity. This novel Bu regimen is comparable to other radiation-free preparative regimens in its effectiveness in the control of HD and with a low-risk of early treatment-related mortality. 相似文献
84.
The authors found tardive dyskinesia (TD) in 23.5% of 200 hospitalized schizophrenic patients, most of whom had received neuroleptic treatment for at least two years. The frequency and severity of TD increased with age, and the more advanced the age at which the patient started taking neuroleptics, the more likely it was that TD would develop. Severe TD was more common in men than in women. Prolonged treatment with neuroleptics or the use of antiparkinsonism drugs increased the risk of TD. 相似文献
85.
86.
Cavitary pneumonia in an AIDS patient caused by an unusual Bordetella bronchiseptica variant producing reduced amounts of pertactin and other major antigens 下载免费PDF全文
Lorenzo-Pajuelo B Villanueva JL Rodríguez-Cuesta J Vergara-Irigaray N Bernabeu-Wittel M Garcia-Curiel A Martínez de Tejada G 《Journal of clinical microbiology》2002,40(9):3146-3154
Although Bordetella bronchiseptica can infect and colonize immunocompromised humans, its role as a primary pathogen in pneumonia and other respiratory processes affecting those patients remains controversial. A case of cavitary pneumonia caused by B. bronchiseptica in an AIDS patient is presented, and the basis of the seemingly enhanced pathogenic potential of this isolate (designated 814) is investigated. B. bronchiseptica was the only microorganism recovered from sputum, bronchoalveolar lavage fluid, and samples taken through the protected brush catheter. Unlike previous work reporting the involvement of B. bronchiseptica in cases of pneumonia, antibiotic treatment selected on the basis of in vitro antibacterial activity resulted in clearance of the infection and resolution of the pulmonary infiltrate. Although isolate 814 produced reduced amounts of several major antigens including at least one Bvg-activated factor (pertactin), the molecular basis of this deficiency was found to be BvgAS independent since the defect persisted after the bvgAS locus of isolate 814 was replaced with a wild-type bvgAS allele. Despite its prominent phenotype, isolate 814 displayed only a modest yet a significant deficiency in its ability to colonize the respiratory tracts of immunocompetent rats at an early time point. Interestingly, the antibody response elicited by isolate 814 in these animals was almost undetectable. We propose that isolate 814 may be more virulent in immunocompromised patients due, at least in part, to its innate ability to produce low amounts of immunogenic factors which may be required at only normal levels for the interaction of this pathogen with its immunocompetent natural hosts. 相似文献
87.
Diisocyanate asthma and gene-environment interactions with IL4RA, CD-14, and IL-13 genes. 总被引:1,自引:0,他引:1
David I Bernstein Ning Wang Paloma Campo Ranajit Chakraborty Andrew Smith André Cartier Louis-Philippe Boulet Jean-Luc Malo Berran Yucesoy Michael Luster Susan M Tarlo Gurjit K Khurana Hershey 《Annals of allergy, asthma & immunology》2006,97(6):800-806
BACKGROUND: Diisocyanate asthma (DA) affects 2% to 10% of exposed workers, yet the pathogenetic mechanisms underlying this disorder remain ill defined. OBJECTIVE: To determine if specific single nucleotide polymorphisms (SNPs) of interleukin 4 receptor alpha (IL4RA), IL-13, and CD14 promoter genes are associated with DA. METHODS: Sixty-two workers with DA confirmed by specific inhalation challenge (SIC) and 75 diisocyanate-exposed, SIC-negative workers were analyzed for SNPs associated with IL4RA, IL-13, and CD14 promoter genes. RESULTS: No associations were found with individual SNPs and DA. When stratified according to specific diisocyanate exposure, a significant association was found between IL4RA (I50V) II and DA among individuals exposed to hexamethylene diisocyanate (HDI) (odds ratio [OR], 3.29; 95% confidence interval [CI], 1.33-8.14; P = .01) only. Similarly, the IL4RA (I50V) II and IL-13 (R110Q) RR combination was significantly associated with DA in HDI-exposed workers (OR, 4.13; 95% CI, 1.35-12.68; P = .01), as was the IL4RA (I50V) II and CD14 (C159T) CT genotype combination (OR, 5.2; 95% CI, 1.82-14.88; P = .002) and the triple genotype combination IL4RA (I50V) II, IL-13 (R110Q) RR, and CD14 (C159T) CT (OR, 6.4; 95% CI, 1.57-26.12; P = .01). CONCLUSIONS: Gene-environmental interactions may contribute to the pathogenesis of DA, and gene-gene interactions may modulate this relationship. 相似文献
88.
Comparative evaluation of the new version of the INNO-LiPA Mycobacteria and genotype Mycobacterium assays for identification of Mycobacterium species from MB/BacT liquid cultures artificially inoculated with Mycobacterial strains 总被引:2,自引:0,他引:2 下载免费PDF全文
Padilla E González V Manterola JM Pérez A Quesada MD Gordillo S Vilaplana C Pallarés MA Molinos S Sánchez MD Ausina V 《Journal of clinical microbiology》2004,42(7):3083-3088
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles. 相似文献
89.
Detection of human metapneumovirus RNA sequences in nasopharyngeal aspirates of young French children with acute bronchiolitis by real-time reverse transcriptase PCR and phylogenetic analysis 总被引:3,自引:0,他引:3 下载免费PDF全文
Bouscambert-Duchamp M Lina B Trompette A Moret H Motte J Andréoletti L 《Journal of clinical microbiology》2005,43(3):1411-1414
90.
Sreenarasimhaiah J Jaramillo A Crippin J Lisker-Melman M Chapman WC Mohanakumar T 《Human immunology》2003,64(2):224-230
Chronic hepatitis C virus (HCV) infection develops in 85% of exposed individuals and 20% develop cirrhosis. However, the pathogenesis of this process is not well-understood. The objective of this study was to determine whether HCV-reactive T cells play a role in the process of development of cirrhosis during chronic HCV infection. We analyzed 21 human leukocyte antigen (HLA)-A2 patients with chronic HCV infection (9 with histology of inflammation and 12 with histology of fibrosis/cirrhosis). The frequency of CD8(+) T cells reactive to 12 HCV-derived epitopes was determined by an interferon-gamma enzyme-linked immunospot (ELISPOT) assay. The frequency of CD4(+) Th1 and Th2 cells reactive to the HCV core antigen was determined by interferon-gamma and interleukin-5 ELISPOT assays, respectively. Patients with histology of inflammation showed a significantly higher CD8(+) T-cell response to five HCV-derived epitopes (YLLPRRGPRL [core], CINGVCWTV [NS3], LLCPAGHAV [NS3], ILAGYGAGV [NS4B], and GLQDCTMLV [NS5B]) as compared with patients with histology of fibrosis/cirrhosis. Also, patients with histology of inflammation showed a significantly higher CD4(+) Th1 response to the HCV core antigen as compared to patients with histology of fibrosis/cirrhosis. These results indicate that a lack of an optimal T-cell response to HCV is associated with the development of cirrhosis during chronic HCV infection. 相似文献