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61.
B cells play an important role in the immune responses which affect the outcomes of kidney allografts. Dynamic changes of B‐cell compartments in clinical kidney transplantation are still poorly understood. B‐cell subsets were prospectively monitored using flow cytometry for 1 year in 98 kidney transplant recipients. Data were correlated with immunosuppression and clinical outcomes. An increase in the total population of B lymphocytes was observed during the first week after transplantation. The level of IgMhighCD38highCD24high transitional B cells reduced significantly up until the third month, with partial repopulation in the first year. Lower numbers of transitional B cells in the third month were associated with higher risk of graft rejection. IgM+IgD+CD27? naive B cells did not change within follow‐up. IgM+CD27+ nonswitched memory B cells and IgM?CD27+ switched memory B cells increased on post‐operative day 7. IgM?CD38highCD27high plasmablasts showed similar kinetics during the first post‐transplant year, similar to transitional B cells. In conclusion, sensitized kidney transplant recipients as well as those with either acute or chronic rejection within the first post‐transplant year exhibited lower levels of transitional B cells. Therefore, these data further support the hypothesis that transitional B cells have a protective role in kidney transplantation.  相似文献   
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Mononuclear phagocytes (bone marrow monocyte-derived macrophages, alveolar macrophages, perivascular macrophages, and microglia) are reservoirs and vehicles of dissemination for the human immunodeficiency virus type-1 (HIV-1). How virus alters mononuclear phagocyte immunoregulatory activities to complete its life cycle and influence disease is incompletely understood. In attempts to better understanding the influence of virus on macrophage functions, we used one-dimensional electrophoresis, and liquid chromatography tandem mass spectrometry to analyze the secretome of HIV-1-infected human monocyte-derived macrophages. We identified 110 proteins in culture supernatants of control (uninfected) and virus-infected cells. Differentially expressed cytoskeletal, enzymes, redox, and immunoregulatory protein classes were discovered and validated by Western blot tests. These included, but were not limited to, cystatin C, cystatin B, chitinase 3-like 1 protein, cofilin-1, l-plastin, superoxide dismutase, leukotriene A(4) hydrolase, and alpha-enolase. This study, using a unique proteomics platform, provides novel insights into virus-host cell interactions that likely affect the functional role of macrophages in HIV disease.  相似文献   
65.
Francisella tularensis (FT) has been classified by the CDC as a category A pathogen because of its high virulence and the high mortality rate associated with infection via the aerosol route. Because there is no licensed vaccine available for FT, development of prophylactic and therapeutic regimens for the prevention/treatment of infection is a high priority. In this report, heat-killed FT live vaccine strain (HKLVS) was employed as a vaccine immunogen, either alone or in combination with an adjuvant, and was found to elicit protective immunity against high-dose FT live vaccine strain (FTLVS) challenge. FT-specific antibodies produced in response to immunization with HKLVS alone were subsequently found to completely protect naive mice against high-dose FT challenge in both infection-interference and passive immunization experiments. Additional passive immunization trials employing serum collected from mice immunized with a heat-killed preparation of an O-antigen-deficient transposon mutant of FTLVS (HKLVS-OAg(neg)) yielded similar results. These findings demonstrated that FT-specific antibodies alone can confer immunity against high-dose FTLVS challenge, and they reveal that antibody-mediated protection is not dependent upon production of LPS-specific antibodies.  相似文献   
66.

Background

Selenium is an essential element which shows protective properties against diverse harmful factors. Lithium compounds are widely used in medicine, but, in spite of undoubted beneficial effects, treatment with these compounds may lead to severe side effects, including renal, gastrointestinal, neurological, endocrine and metabolic disorders. This study was aimed at evaluating the influence of selenium and/or lithium on lithium, iron, zinc and copper content in rats’ erythrocytes as well as estimate the action of additional selenium on lithium exposure effects.

Methods

The experiment was performed on four groups of rats (six animals each): control – received saline; Li – received 2.7 mg Li/kg b.w. as lithium carbonate; Se – received 0.5 mg Se/kg b.w. as sodium selenite; Se + Li – received simultaneously 0.5 mg Se/kg b.w. and 2.7 mg Li/kg b.w. (sodium selenite and lithium carbonate). The administration was performed for three weeks, once a day by stomach tube, in form of water solutions. In erythrocytes the content of lithium, iron, zinc and copper was determined using flame atomic absorption spectroscopy.

Results

Lithium treatment insignificantly disturbed iron and zinc homeostasis as well as markedly increased lithium accumulation and copper content in rat erythrocytes. Selenium coadministration reversed those effects.

Conclusions

The beneficial effect of selenium on disturbances of studied microelements homeostasis as well as on preventing lithium accumulation in erythrocytes in Li receiving animals allows suggesting that further research on selenium application as an adjuvant in lithium therapy is worth carrying on.  相似文献   
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Purpose

The main purpose of this study was to analyze the characteristics of dyspepsia and contributing factors in Montenegrin maintenance hemodialysis patients.

Methods

The study included 43 patients undergoing hemodialysis with symptoms of dyspepsia and 40 control dyspeptic subjects with preserved kidney function. All subjects underwent an interview about dyspeptic symptoms, physical and biochemical examination, and upper gastrointestinal endoscopy with pathohistological analysis of biopsy specimens.

Results

Early satiety, bloating and heartburn were the most common symptoms in hemodialysis patients but without significant difference in frequency in relation to controls. Chronic kidney disease patients had statistically lower concentration of total proteins and albumin (p?<?0.001), as well lower BMI values (p?=?0.002). Despite this, no significant correlation of laboratory parameters with dyspeptic symptoms was found. Pathohistological examination indicated that the most common finding in hemodialysis patients was chronic active gastritis (58%), while chronic atrophic gastritis was significantly more common in dialytic patients (p?=?0.032). Patients on hemodialysis had more frequently atrophy of corpus mucosa, which was positively related to dialysis duration (p?=?0.001) and negatively related to pH values (p?=?0.004) and bicarbonate concentration (p?=?0.049). Helicobacter pylori was considerably more common in patients who underwent shorter time on hemodialysis (p?<?0.001) and had higher values of bicarbonate (p?=?0.037).

Conclusion

Maintenance hemodialysis patients are at risk for chronic gastric diseases that correlated with both dialysis vintage and duration.

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International Urology and Nephrology - Data on the seroprevalence of hepatitis E virus (HEV) in heamodialysis (HD) patients are conflicting, ranging from 0 to 44%. The aim of this study was to...  相似文献   
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