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101.
Vali B Yue FY Jones RB Sheth PM Kaul R Betts MR Wong D Kovacs C Loutfy M Common A Halpenny R Ostrowski MA 《PloS one》2008,3(10):e3454
Background and Aims
Hepatitis C Virus (HCV)-related liver disease progresses more rapidly in individuals co-infected with Human Immunodeficiency Virus-1 (HIV), although the underlying immunologic mechanisms are unknown. We examined whether HIV-specific T-cells are identified in the liver of HCV/HIV co-infected individuals and promote liver inflammation through bystander immune responses.Methods
Ex-vivo intra-hepatic lymphocytes from HCV mono-infected and HCV/HIV co-infected individuals were assessed for immune responses to HIV and HCV antigens by polychromatic flow cytometry.Results
HCV/HIV liver biopsies had similar frequencies of lymphocytes but lower percentages of CD4+ T-cells compared to HCV biopsies. In co-infection, intra-hepatic HIV-specific CD8+ and CD4+ T-cells producing IFN-γ and TNF-α were detected and were comparable in frequency to those that were HCV-specific. In co-infected individuals, viral-specific CD8+ T-cells produced more of the fibrogenic cytokine, TNF-α. In both mono- and co-infected individuals, intra-hepatic HCV-specific T-cells were poorly functional compared to HIV-specific T-cells. In co-infection, HAART was not associated with a reconstitution of intra-hepatic CD4+ T-cells and was associated with reduction in both HIV and HCV-specific intra-hepatic cytokine responses.Conclusion
The accumulation of functional HIV-specific T-cells in the liver during HCV/HIV co-infection may represent a bystander role for HIV in inducing faster progression of liver disease. 相似文献102.
Kehmia Titanji Aswani Vunnava Anandi N. Sheth Cecile Delille Jeffrey L. Lennox Sara E. Sanford Antonina Foster Andrea Knezevic Kirk A. Easley M. Neale Weitzmann Ighovwerha Ofotokun 《PLoS pathogens》2014,10(11)
HIV infection is associated with high rates of osteopenia and osteoporosis, but the mechanisms involved are unclear. We recently reported that bone loss in the HIV transgenic rat model was associated with upregulation of B cell expression of the key osteoclastogenic cytokine receptor-activator of NF-κB ligand (RANKL), compounded by a simultaneous decline in expression of its physiological moderator, osteoprotegerin (OPG). To clinically translate these findings we performed cross-sectional immuno-skeletal profiling of HIV-uninfected and antiretroviral therapy-naïve HIV-infected individuals. Bone resorption and osteopenia were significantly higher in HIV-infected individuals. B cell expression of RANKL was significantly increased, while B cell expression of OPG was significantly diminished, conditions favoring osteoclastic bone resorption. The B cell RANKL/OPG ratio correlated significantly with total hip and femoral neck bone mineral density (BMD), T- and/or Z-scores in HIV infected subjects, but revealed no association at the lumbar spine. B cell subset analyses revealed significant HIV-related increases in RANKL-expressing naïve, resting memory and exhausted tissue-like memory B cells. By contrast, the net B cell OPG decrease in HIV-infected individuals resulted from a significant decline in resting memory B cells, a population containing a high frequency of OPG-expressing cells, concurrent with a significant increase in exhausted tissue-like memory B cells, a population with a lower frequency of OPG-expressing cells. These data validate our pre-clinical findings of an immuno-centric mechanism for accelerated HIV-induced bone loss, aligned with B cell dysfunction. 相似文献
103.
The effects of cadmium chloride (Cd) alone (1 mg given as a single injection) or in combination with ascorbic acid (AA; 100 mg/day for 10 days) on the secretory functions of sex accessory glands of rats were studied in healthy male albino rats. Animals were sacrificed after 10 days treatment and the seminal vesicles (SVs), dorsolateral prostate (DLP), ventral prostate (VP), bulbourethral glands (BU), and coagulating glands (CO) were excised and weighed. Weight of all accessory glands were decreased by 10 days treatment with Cd. Cd + AA gave similar results. AA concentration increased in all glands and was significantly increases in CO (p less than .01). Levels of ascorbogin increased in all glands except CO and BU and in the latter a significant (p less than .001) increase was found. The rate of AA utilization increased significantly (p less that .001) in the accessories. A significant (p less than .001) reduction in the activity of succinate dehydrogenase was observed in Cd-treated rats with a further reduction with combined treatment. Alkaline phosphatase decreased (p less than .001) after Cd treatment but AA in combination restored it to control levels. Cd increased acid phosphatase (p less than .001) and was further activated by Cd + AA. Phosphorylase activity was elevated with Cd (p less than .001) but recovery occurred in SV and BU with Cd + AA. Glycogen increased (p less than .001; .01) with both treatments as did citric acid. Protein results were inconsistent with Cd but activation was found in most glands under combined treatment. The results reveal that most androgen-dependent biochemical constituents and organ weights were affected significantly by a single injection of Cd. AA had a protective and beneficial influence on the restoration of structural integrity and metabolism in sex accessory glands. 相似文献
104.
P S Mandrekar A R Sheth V M Doctor J P Zaveri N A Sheth 《Indian journal of experimental biology》1990,28(2):111-113
Using indirect immuno-peroxidase staining technique, localization of immunoreactive follicle-stimulating hormone (IR-FSH) is demonstrated in the cytoplasm of the epithelial cells of normal human stomach. In view of their triangular shape and central nucleus and their predominance in the intermediate glands of the gastric mucosa, these cells are identified as parietal cells. The stromal tissue is devoid of staining reaction. 相似文献
105.
In vitro incubation of rat epididymal sperm with antiserum to human seminal plasma inhibin (As hSPI) caused agglutination of the sperm. In vivo administration of As hSPI to adult male rats resulted in a significant decrease in testicular as well as epididymal sperm counts. Furthermore, the majority (almost 90%) of the epididymal sperm were agglutinated. When these animals were mated with normal cycling females, significant reduction in fertility was observed. 相似文献
106.
Sequential resonance assignment of the 500-MHz nmr spectrum of d-(CG)6 and its structure under low-salt conditions 总被引:1,自引:0,他引:1
Two-dimensional (2D) nmr methods (correlated spectroscopy, nuclear Overhauser enhancement spectroscopy, and relayed correlated spectroscopy) have been used to obtain resonance assignment of the nonexchangeable base and sugar protons of a double-helical DNA segment, d-(CG)6 in D2O solutions under conditions of low ionic strength. Detailed information about the glycosidic torsion angle, sugar geometry, stacking patterns of the bases, and the overall solution structure of the dodecanucleotide has been obtained from the relative intensities of cross-peaks in the 2D spectra. The molecule shows general features of B-DNA under the experimental conditions employed. However, in spite of the repeating base sequence, there are subtle and detectable variations in the structure along the double helix. The terminal residues show considerable conformational flexibility. 相似文献
107.
Characteristics of prolactin receptors of murine mammary glands were studied. Mammary gland exhibited low but specific binding to 125I-rPRL (rat prolactin). Receptors were heat susceptible and partly protein in nature. Theophylline--both in vitro and in vivo treatment--enhanced the binding of 125I-rPRL to receptors. It remains to be established whether this action of theophylline is mediated through cyclic AMP "Sparing" effect or through its direct effect on cell membrane stabilization. 相似文献
108.
The content of hypothalamic LHRH and concentration of LH in pituitary and plasma were measured on day 5, 7, 10, 14, 17, 22, 25, 30, 45, 52 and 60 in male rats which were bilaterally castrated on day 2. The levels of plasma LH were significantly higher in all the groups of castrated rats than in normal male rats of corresponding ages. The concentration of plasma LH did not rise progressively but showed day to day fluctuation apparently due to alteration of sexual differentiation of the hypothalamus. The concentration of pituitary LH was significantly lower in neonatally castrated rats compared to normal male rats except on days 17, 25 and 30. The content of hypothalamic LHRH declined initially following castration, but from day 17 onwards significantly higher levels of hypothalamic LHRH were maintained in neonatally castrated rats than in intact control. Initial decline in the content of hypothalamic LHRH may be because of stimulation of release of LHRH which exceeds maximal rate of synthesis and subsequent increase in the content of hypothalamic LHRH may be due to enhanced LHRH synthesis as a result of castration. 相似文献
109.
Activity profile of Centchroman in healthy female volunteers 总被引:1,自引:0,他引:1
R Vaidya U Joshi P Meherji N Rege S Betrabet L Joshi A Sheth P K Devi 《Indian journal of experimental biology》1977,15(12):1173-1176
110.
Sanjay P. Chauhan N. R. Sheth I. S. Rathod B. N. Suhagia Rajnikant B. Maradia 《Phytochemistry Reviews》2013,12(1):35-45
Betalains are of great taxonomic significance in higher plants and occur only in 10 families of the order Caryophyllales (Centrospermae). They are water-soluble nitrogenous pigments. They can be divided into two major structural groups, the red to red-violet betacyanins and the yellow betaxanthins. Betalains are widely used as natural red food colorant as well as antioxidant potentials. Several methods have been published for the determination of betalain in fruits of Opuntia species. The purpose of the current review is to provide a systematic survey of the analytical techniques for the determination of betalain from fruits of Opuntia species. 相似文献