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81.
M P Nair S A Schwartz R Polasani J Hou A Sweet K C Chadha 《Clinical and Vaccine Immunology : CVI》1997,4(2):127-132
It is now well established that parenteral drug abuse is a significant risk factor for contracting human immunodeficiency virus type 1 (HIV-1) infection and subsequently developing AIDS. Earlier studies have shown that morphine can modulate various immune responses and therefore support the premise that morphine is a cofactor in susceptibility to and progression of HIV infection. Dysregulation of interferon (IFN) production, nonspecific apoptosis of T cells, and the immune response to soluble HIV gene products have been associated with potential mechanisms of pathogenesis in HIV disease. The present study was undertaken to examine the immunomodulatory role of morphine on HIV protein-induced lymphocyte proliferative responses, Sendai and Newcastle disease virus-induced alpha IFN (IFN-alpha) and IFN-beta production by lymphocytes and fibroblast cells, respectively, and induction of apoptosis of normal lymphocytes in vitro. Our results demonstrate that HIV protein-induced human lymphocyte proliferative responses were significantly inhibited by morphine in a dose-dependent manner. Furthermore, morphine significantly inhibited both IFN-alpha and IFN-beta production by normal lymphocytes and fibroblasts but induced apoptosis of normal lymphocytes. Inhibition of IFN-alpha production by morphine could be reversed by the opiate receptor antagonist naloxone. This suggests that the immunomodulatory effects of morphine are mediated through the opioid receptor. These studies support a role of morphine as a cofactor in the pathogenesis of HIV infection and describe some of the possible pathologic mechanisms which underlie the immunoregulatory effects of morphine. 相似文献
82.
Focal, spontaneous cell death in the rat aortic endothelium was demonstrated by cytochemistry. Cells with intracellular calcium deposits, indicating cell death with mitochondrial calcification, were identified by chlorotetracycline fluorescence. The same cells also contained cytoplasmic IgG, which binds to cytoskeletal components of the dead cell. The immunocytochemical detection of IgG in en face preparations was used as a quantitative method for detecting cell death in the aortic endothelium. The use of an indirect immunoperoxidase technique and "Häutchens" of paraformaldehyde-fixed tissue provided high sensitivity and cellular recovery with low background. A cell death frequency of 0.19% +/- 0.04% was observed in 5-month-old Sprague-Dawley rats. When compared with the replication rate of aortic endothelium in these animals, the data suggest that dead cells remain in the endothelium for more than 24 hours. This conclusion was supported by in vitro studies. Confluent cultures of bovine aortic endothelium were pulsed with trypan blue, and the residence time of blue cells was 3.5-4 days in non-flow culture system. Time-lapse video microscopy showed a prolonged cell death process with a phase of rapid intracellular movements, followed by undermining by surrounding cells and fragmentation of the dead cell. Migration of surrounding cells rapidly covered partial detachments of the dead cell, so that no holes could be detected in the monolayer when the dead cell finally detached. It is concluded that the normal turnover of cells in the aortic endothelium involves a prolonged phase of in situ cell death and finally detachment with very little or no exposure of subendothelial structures. 相似文献
83.
Summary. Iris yellow spot virus (IYSV), a tentative virus species in the genus Tospovirus and family Bunyaviridae, is considered a rapidly emerging threat to onion production in the western United States (US). The present study was undertaken
to determine the sequence diversity of IYSV isolates from infected onion plants grown in California, Colorado, Idaho, Oregon,
Utah and Washington. Using primers derived from the small RNA of IYSV, the complete sequence of the nucleoprotein (NP) gene
of each isolate was determined and the sequences compared. In addition, a shallot isolate of IYSV from Washington was included
in the study. The US isolates of IYSV shared a high degree of sequence identity (95 to 99%) with one another and to previously
reported isolates. Phylogenetic analyses showed that with the exception of one isolate from central Oregon and one isolate
from California, all the onion and shallot isolates from the western US clustered together. This cluster also included onion
and lisianthus isolates from Japan. A second distinct cluster consisted of isolates from Australia (onion), Brazil (onion),
Israel (lisianthus), Japan (alstroemeria), the Netherlands (iris) and Slovenia (leek). The IYSV isolates evaluated in this
study appear to represent two distinct groups, one of which largely represents isolates from the western US. Understanding
of the population structure of IYSV would potentially provide insights into the molecular epidemiology of this virus. 相似文献
84.
The distribution of a high affinity enkephalin-dipeptidylcarboxypeptidase between regions of mouse brain is markedly heterogenous and parallels that of opiate receptors. Furthermore intrastriatal administration of kainic acid as well as interruption of the nigrostriatal dopaminergic pathway by 6-hydroxydopamine (6-OHDA) lead to similar decreases in this peptidase activity and in the number of opiate receptors. On the contrary, no correlation was found between low affinity enkephalin degrading enzymes and opiate receptors. 相似文献
85.
86.
Effects of a yearlong moderate-intensity exercise and a stretching intervention on sleep quality in postmenopausal women 总被引:4,自引:0,他引:4
Tworoger SS Yasui Y Vitiello MV Schwartz RS Ulrich CM Aiello EJ Irwin ML Bowen D Potter JD McTiernan A 《Sleep》2003,26(7):830-836
STUDY OBJECTIVES: To examine the effects of a moderate-intensity exercise or stretching intervention and changes in fitness, body mass index, or time spent outdoors on self-reported sleep quality and to examine the relationship between the amount and timing of exercise and sleep quality. DESIGN: A randomized intervention trial. SETTING: A cancer research center in Seattle, Washington. PARTICIPANTS: Postmenopausal, overweight or obese, sedentary women not taking hormone replacement therapy, aged 50 to 75 years, and recruited from the Seattle metropolitan area. INTERVENTIONS: A yearlong moderate-intensity exercise (n=87) and a low-intensity stretching (n=86) program. MEASUREMENTS AND RESULTS: Among morning exercisers, those who exercised at least 225 minutes per week had less trouble falling asleep (odds ratio [OR]: 0.3, P < or = .05) compared with those who exercised less than 180 minutes per week. However, among evening exercisers, those who exercised at least 225 minutes per week had more trouble falling asleep (OR: 3.3, P < or = .05) compared to those who exercised less than 180 minutes per week. Stretchers were less likely to use sleep medication (OR = 0.4, P < or = .05) and have trouble falling asleep (OR: 0.7, P < or = .10) during the intervention period compared with baseline. A greater than 10% versus a 1% or less increase in maximum O2 consumption over the year was associated with longer sleep duration (P < or = .05), less frequently falling asleep during quiet activities (P < or = .05), and less use of sleep medication (P < or = .05). Reductions in body mass index and increases in time spent outdoors had inconsistent effects on sleep quality. CONCLUSIONS: Both stretching and exercise interventions may improve sleep quality in sedentary, overweight, postmenopausal women. Increased fitness was associated with improvements in sleep. However, the effect of moderate-intensity exercise may depend on the amount of exercise and time of day it is performed. 相似文献
87.
Pathology of the Glomerulus in Sickle Cell Anemia With and Without Nephrotic Syndrome 总被引:1,自引:0,他引:1 下载免费PDF全文
I. Bruce Elfenbein Arthur Patchefsky William Schwartz Andrew G. Weinstein 《The American journal of pathology》1974,77(3):357-376
Glomeruli from 6 cases of sickle cell disease (SS) with the nephrotic syndrome (NS) were compared histologically and quantitatively with glomeruli from 9 cases of SS, 10 cases of sickle cell trait (SCT), 4 cases of other hemoglobinopathies, all without NS, and normal controls. Five of 6 patients with SS and NS had extensive reduplication of their glomerular basement membranes and mild mesangial proliferation. Similar but milder lesions occurred in SS without NS but not in SCT or controls. Incidental renal disease occurred in 1 patient with SS and NS. Nephrotic syndrome was probably secondary to effects of sickle cell disease. Glomeruli in SS were significantly larger (>70%) than in SCT and controls. Mean total glomerular area per unit area of cortex in SS with normal BUN significantly exceeded that of SCT, which, in turn, was significantly greater than that of controls. Mechanisms for the histologic lesions and hypertrophy of the glomeruli were suggested. 相似文献
88.
89.
Touchman JW Dehejia A Chiba-Falek O Cabin DE Schwartz JR Orrison BM Polymeropoulos MH Nussbaum RL 《Genome research》2001,11(1):78-86
The human alpha-synuclein gene (SNCA) encodes a presynaptic nerve terminal protein that was originally identified as a precursor of the non-beta-amyloid component of Alzheimer's disease plaques. More recently, mutations in SNCA have been identified in some cases of familial Parkinson's disease, presenting numerous new areas of investigation for this important disease. Molecular studies would benefit from detailed information about the long-range sequence context of SNCA. To that end, we have established the complete genomic sequence of the chromosomal regions containing the human and mouse alpha-synuclein genes, with the objective of using the resulting sequence information to identify conserved regions of biological importance through comparative sequence analysis. These efforts have yielded approximately 146 and approximately 119 kb of high-accuracy human and mouse genomic sequence, respectively, revealing the precise genetic architecture of the alpha-synuclein gene in both species. A simple repeat element upstream of SNCA/Snca has been identified and shown to be necessary for normal expression in transient transfection assays using a luciferase reporter construct. Together, these studies provide valuable data that should facilitate more detailed analysis of this medically important gene. 相似文献
90.
De novo 13q partial duplication identified by cytogenetic, biochemical and molecular approaches 总被引:1,自引:0,他引:1
S. Schwartz M. Harris R. Ehrenpreis A. Zaslav L. J. Raffel M. F. Schwartz E. Lieber M. M. Cohen 《Clinical genetics》1991,40(6):417-422
A 3.5-month-old female infant manifesting dysmorphic facies, developmental delay and failure to thrive was referred for cytogenetic evaluation. Peripheral lymphocytes revealed three chromosomally distinct cell lines: 46,XX/46,XX,10p+/47,XX,10p+,+mar. Dermal fibroblasts revealed only the 46,XX,10p+cell line. High resolution G-, R-, and Q-banding suggested that the extra chromosomal material (10p+) represented a duplication of the segment 13q14----13qter. Parental karyotypes were normal. As absolute identification of de novo chromosomal abnormalities, based solely on cytogenetic studies, is sometimes difficult, both biochemical and molecular approaches were undertaken to elucidate this abnormality in more detail. Dosage effects were examined using esterase D (localized to 13q14.1) and the DNA probes p1E8 and p9A7 (localized to 13q22 and 13q31/32, respectively). These studies suggested the presence of only 2 copies of esterase D, but 3 copies of both DNA probes, allowing identification of the breakpoint at 13q14.2. 相似文献