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941.
Epstein-Barr viral load as a marker of lymphoma in AIDS patients 总被引:5,自引:0,他引:5
Fan H Kim SC Chima CO Israel BF Lawless KM Eagan PA Elmore S Moore DT Schichman SA Swinnen LJ Gulley ML 《Journal of medical virology》2005,75(1):59-69
Epstein-Barr virus (EBV) is implicated in the pathogenesis of acquired immunodeficiency syndrome (AIDS) lymphoma, and viral DNA is present within the malignant cells in about half of affected patients. We examined the extent to which EBV viral load is elevated in the plasma of AIDS lymphoma patients compared to AIDS patients with opportunistic infections. Sixty-one AIDS patients were studied including 35 with lymphoma (24 non-Hodgkin, six Hodgkin, and five brain lymphoma) and 26 with various opportunistic infections. In situ hybridization revealed EBV encoded RNA (EBER) expression in the malignant cells of 17/28 AIDS lymphomas (61%). In 232 serial plasma samples from 35 lymphoma patients and in 128 samples from AIDS controls, EBV viral load was assayed by quantitative-polymerase chain reaction (Q-PCR) using a TaqMan probe targeting the BamH1W sequence. EBV was detected in plasma from all 17 EBER-positive AIDS lymphoma patients, with viral loads ranging from 34 to 1,500,000 copies per ml (median 3,210). Viral load usually fell rapidly upon initiation of lymphoma therapy and remained undetectable except in two patients with persistent tumor. In 11 AIDS patients, whose lymphoma lacked EBER expression, and in 26 control patients without lymphoma, levels of EBV in plasma were usually low or undetectable (range 0-1,995 and 0-2,409, median 0 and 0, respectively). There was no association between EBV viral load and human immunodeficiency virus (HIV) load or CD4 count. In conclusion, EBV viral load shows promise as a tool to assist in diagnosis and management of EBV-related lymphoma patients. 相似文献
942.
This cross‐sectional study identified variables associated with protease inhibitor (PI) non‐adherence in 179 patients taking anti‐retroviral therapy. Univariate analyses identified 11 variables associated with PI non‐adherence. Multiple logistic regression modelling identified three predictors of PI non‐adherence: low adherence self‐efficacy and seriousness of non‐adherence and HIV (p < .001), perceived absence of HIV associated illness (p < .01), and use of more than one type of recreational drug (p = .001). The model correctly classified 83.9% of the sample, offers psychologists insight into psychological barriers to treatment adherence to guide interventions for improving adherence, and supports a modified version of the reformulated health belief model. 相似文献
943.
Roger P. Farrar S.Mehdi Rezazadeh Jim L. Morris Jo Ellen Dildy Kim Gnau Steven W. Leslie 《Neuroscience letters》1989,100(1-3):319-325
Several lines of experimental evidence support an association between altered Ca2+ regulation and aging. It has been supposed that free cytosolic Ca2+ concentrations ([Ca2+]i) may decrease or increase in aged animals. In this study, both resting and KCl-stimulated [Ca2+]i were measured in purified cortical synaptosomes from young (3 mo.), middle-aged (12 mo.), and old (24 mo.) Fischer 344 rats. Two additional groups of rats were included, one middle-aged and one old which were trained on a treadmill for 6 months prior to experimentation. The [Ca2+]i was determined using the fluorescent Ca2+ chelator fura-2. Net KCl-dependent changes (ΔK) in [Ca2+]i were determined by the difference between stimulatory (100 μM Ca2+/60 mM KCl) and resting (100 μM Ca2+/5 mM KCl buffer) conditions among the 3 age groups. Significant increases in [Ca2+]i were observed in each age group upon depolarization with 60 mM KCl. However, there were no significant age-dependent differences in either resting [Ca2+]i or KCl-stimulated [Ca2+]i. 相似文献
944.
Computed tomography (CT) immediately after double-contrast shoulder arthrography was taken in twenty-two young male patients with anterior shoulder instability including recurrent dislocation and subluxation. This recently developed technique called CT arthrography can provide significant information about patients with glenohumeral instability which is difficult to obtain by conventional arthrography. Information about glenoid labrum pathology is useful for proper management of the shoulder with instability. Lesions identified in this study include anterior labral defects (attenuation, tear, displacement), anterior capsular distension and/or detachment, Hill-Sachs lesion, anterior glenoid rim compression fracture, and fracture of scapula. This article describes the method used in CT arthrography of the glenohumeral joint, reviews the normal cross-sectional anatomy, and emphasizes the importance of the application of CT arthrography in the shoulder disorder with instability. CT arthrography of the glenohumeral joint is easy to perform, is accurate, and has lower radiation dose than arthrotomography. 相似文献
945.
Neonatal injection of BALB/c mice with antibodies specific for the idiotype of TEPC-15 myeloma protein (T15id), which is serologically identical to the major idiotype of anti-phosphorylcholine (PC) antibody, renders the recipients completely unresponsive to PC. C57BL/6, (BALB/c X C57BL/6)F1 and C.B20 mice, similarly treated with anti-T15id antibody, also displayed tolerance to PC although they were relatively more resistant (8-13%) than BALB/c mice (less than 2% control response). When anti-T15id antibody was injected into 15-day-old neonates, the resistance to the tolerance in C57BL/6 and C.B20 mice was much more apparent (up to 80% of the control response) in contrast to that in BALB/c mice, which was not significant. Adoptive transfer of spleen cells from idiotypically suppressed BALB/c mice into 20-day-old, normal C. B20 mice resulted in suppression of T15id but not in tolerance to PC, due to increased production of non-T15id-bearing anti-PC antibody. These results suggest that the ability of clonal compensation for T15id suppression is acquired during early life (2-10 days), under the influence of gene(s) associated or linked with the Igh. 相似文献
946.
947.
Moon EJ Lee JY Kim CK Cho BH 《Journal of biomedical materials research. Part B, Applied biomaterials》2005,73(2):338-346
Various dental restorative composite resins containing 2,2-bis-[4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA) derivatives and spiro orthocarbonates (SOCs) were explored for minimizing the volumetric shrinkage that generally occurs during polymerization. Previous reports suggested mixing Bis-GMA with its derivative TMBis-GMA (2,2-bis[3,5-dimethyl-4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane) to obtain a dental composite with low volumetric shrinkage. It was hypothesized that spiro orthocarbonates would expand volumetrically during polymerization, because of their sophisticated ring-opening reactions; therefore several of them were added to the mixture of Bis-GMA and TMBis-GMA to bring about further reductions in volumetric shrinkage. It was indeed possible to reduce the extent of volumetric shrinkage of dental composites containing SOCs, and to do so without compromising these resins' mechanical properties. 相似文献
948.
Kim SN Rhee JH Song YH Park DY Hwang M Lee SL Kim JE Gim BS Yoon JH Kim YJ Kim-Ha J 《Neurobiology of aging》2005,26(7):1083-1091
Previous gene expression profiling studies in Drosophila have provided clues for understanding the aging process at the gene expression level. For a detailed understanding, studies of specific regions of the body are necessary. We therefore employed microarray analysis to examine gene expression changes in the Drosophila head during aging. Six hundred and eighty-four of the 5405 genes present in the microarray showed significant age-dependent changes as determined by significance analysis of microarray (SAM) (q < 0.05). The biological significance of the changes was analyzed using the gene annotations provided by the Gene Ontology Consortium. Major changes involved genes affecting energy metabolism (proton transport, energy pathways, oxidative phosphorylation) and neuronal function, especially responses to light. Genes involved in protein catabolism and several other metabolic processes also showed age-dependent changes. Most of the changes were reductions in gene expression and occurred before day 13 of adult life. After day 13, the age-dependent gene expression changes were relatively smaller than earlier life. Interestingly, the two biological processes of major gene expression changes are related to the two known environmental changes that increase life span in Drosophila: caloric restriction and light reduction. Our findings suggest that light signaling and energy metabolism may be important biological processes affected by aging and be interesting targets for the further investigation related to the longevity in Drosophila. 相似文献
949.
For both practical and methodological reasons, mice have been the most widely employed species for development of transgenic and gene knockin and knockout animals. However, basic behavioral and physiology control and regulatory mechanisms in mice are not well characterized. To broaden our understanding of the processes maintaining body fluid and blood pressure homeostasis in the mouse, the objectives of this study were to evaluate voluntary water, and sodium intakes during the development of renal hypertension and to examine the relationship between hypertension and the quantities of water and salt ingested. In male, C57BL/6J mice, two-kidney, one-clip renal hypertension (2K-1C) was induced, and water and 1.8% NaCl intakes were monitored for 2 weeks. At the end of this period, all animals received arterial catheters for direct recording of blood pressure. The mice that received renal artery clips were sorted into hypertensive (152+/-4 mm Hg) and normotensive (122+/-2 mm Hg) groups and were compared to control (117+/-4 mm Hg) animals that underwent a sham renal clipping procedure. Hypertensive 2K-1C animals had significantly elevated water intake compared to control animals. On most of the postsurgical days, the normotensive 2K-1C animals did not display increased water intake in comparison to the control group. No significant effect was detected for 1.8% saline intake between any of the pairs of groups. In summary, the reduction of blood flow to a single kidney in the 2K-1C model of renal hypertension induces high blood pressure accompanied by sustained hyperdipsia in the mouse. 相似文献
950.
Won MH Kang T Park S Jeon G Kim Y Seo JH Choi E Chung M Cho SS 《Neuroscience letters》2001,301(2):139-142
Delayed neuronal death in the CA1 of the hippocampus following global ischemia has been evoked by both the activation of N-methyl-D-aspartate receptor (NR) and the generate reactive oxygen species in the neurons. In the present study, we investigated whether oxidative DNA damages may be correlated with NR subunits (NR1 and NR2A/B) expression following ischemia insults in vivo. Thirty minutes after ischemia-reperfusion, the intensities of both NR and 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunoreactivities were markedly increased in neurons of CA1. However, NR2A/B and 8-OHdG immunoreactivities were enhanced in CA1 over 24 h after ischemia although NR1 immunoreactivity was decreased. These results suggest that oxidative stress and excitotoxicity in the CA1 may simultaneously trigger neuronal damages at early time after ischemia, and free radical damage including oxidative DNA damage may eventually promote the delayed neuronal death in this region. 相似文献