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1.
Since cyclosporin A (CsA), a widely used immunosuppressive drug, strongly suppresses interleukin-2 (IL-2) secretion, it is frequently difficult to estimate T lymphocyte activation in early acute rejection. We found that, when evaluated based on HLA-DQ antigen expression, monocyte activation in the peripheral blood of renal transplantation patients was a very sharp parameter in diagosing acute rejection. All of 16 episodes of early acute rejection, which were relatively easily suppressed by steroid pulse therapy, showed a sharp increase in the proportion of HLA-DQ antigen-positive monocytes (DQ+ mono) and a quick return of DQ+ mono to previous values, along with a fall in serum creatinine levels. Since, however, HLA-DR antigen-positive T lymphocytes (DR +T) were markedly increased over a long period in episodes of therapy-resistant and chronic rejection, their prolonged high value was regarded as a parameter indicative of poor prognosis.  相似文献   
2.
Abstract A study was conducted to elucidate the mechanism of donor-pecific Mixed Lymphocyte Reaction (MLR and Cell Mediated Lymphotoxicity (CML) unresponsiveness in a renal transplant recipient with a long-term well-functioning kidney. The peripheral blood lymphocytes (PBL) of the recipient, who had not shown rejection since his transplantation 5 years previously, and those of his mother (donor), his father and two healthy third parties were examined. MLR, CML, semimicro MLR in a double chamber, interleukin-2 (IL-2) synthesis assay and limiting dilution assay were performed. This recipient showed donor-pecific MLR and CML unresponsiveness. IL-2 assay showed that the PBL of the recipient produced less IL-2 against the donor than against the father and the third parties. The addition of exogenous recombinant IL-2 (rIL-2; Takeda Co.) to the priming MLR caused a recovery of CML against the donor. A limiting dilution assay indicated that cytotoxic T cell precursor (CTLp) frequencies against the donor and father did not differ. The suppressor assay in a double chamber indicated that the PBL of the recipient stimulated by the donor PBL had a non-pecific suppressive effect on MLR, CML and IL-2 synthesis of the PBL across the Major Histocompatibility Complex (MHC) barrier. This suppressive effect was abolished by OKT3 or OKT8 monoclonal antibody and complement. Thus, the recipient had donor-pecific suppressor T cells that produced a humoral non-pecific suppressive factor only when stimulated by the donor PBL, and this factor suppressed PLR and CML by inhibiting IL-2 synthesis of the PBL.  相似文献   
3.
Telomerase activity in 16 pleural effusions was studied using an in situ telomerase repeat amplification protocol (TRAP) assay on cytospin preparations. Six of nine cytologically malignant specimens contained telomerase-positive cells (67%), and in two further specimens, suspicious positive cells were seen. Two of four atypical specimens contained telomerase-positive cells, whereas two benign cases were telomerase-negative. No mesothelial cells showed telomerase reactivity. Thus, telomerase activity was specific for malignancy and it was always found only in malignant cells. The results suggest that telomerase activity measured with this in situ method can be a valuable complement in the assessment of malignancy in pleural effusions.  相似文献   
4.
Summary Effects of 10 weeks of physical training on free radical scavenging enzyme systems in erythrocytes were investigated in 7 sedentary healthy male students. The training consisted of running over 5 km, 6 times/week. Their maximum oxygen uptake and 12 min walk-run performance increased significantly after training. Of the antioxidant enzyme systems examined in the erythrocytes, both catalase activity and concentration and total glutathione reductase (GR) activity also showed significant increases following the training. The erythrocyte GR activity coefficient also increased significantly. These results suggest that chronic aerobic exercise increases riboflavin requirements and has some positive effects on antioxidative processes.  相似文献   
5.
Fracture risk is influenced by both bone strength and by falls. Measures of physical function and performance are predictors of falls. However, the interrelationships among bone mineral density (BMD), regular physical activity, and measures of physical performance are not well known. We studied 447 community-dwelling Japanese people aged 40 years and over (96 men and 351 women) to examine the association of calcaneus BMD with measures of physical performance (grip strength, walking speed, chair stand, and functional reach) and regular physical activity. Calcaneus BMD decreased with age by approximately 25% in men and 42% in women. Measures of physical performance decreased with age by approximately 30% in both genders, however, performance on the chair stand test declined by approximately 60%. There were only minimal differences in performance measures and calcaneus BMD between people with and those without regular physical activity in both genders, and most differences were not significant. However, there were significant BMD increases of 3–6% per standard deviation (SD) increase in all performance measures for women and a 7% increase in BMD per SD increase in grip strength for men, after adjusting for age. These associations remained after additional adjustment for body mass index and regular physical activity. These findings suggest that bone density and physical function decline markedly in both men and women with age, and that low BMD and poor function tend to occur together, which would increase fracture risk more than either risk factor alone. Received: 9 August 1999 / Accepted: 4 February 2000  相似文献   
6.
A 66-year-old woman was admitted to our hospital for evaluation of edema of the extremities. Laboratory findings suggested that she had nephrotic syndrome and chronic lymphocytic leukemia (CLL). Renal biopsy (with PAM staining) showed a spike formation in the capillary wall. Immunofluorescent staining revealed deposition of immunoglobulin G (IgG) and the third component of complement in the glomerular basement membrane. Electron microscopy showed fibrillary deposits in the subepithelium. These findings indicated membranous glomerulonephritis (MGN). In addition, focal segmental sclerosis and interstitial lymphocytic infiltration were observed in the renal biopsy specimen. In CLL patients nephrotic syndrome occurs rarely. Even if the complication occurs, MGN is not frequent. Both diseases are suspected to occur in association with each other, and immunologic abnormality contributes to their coexistence. Although administration of prednisolone and endoxan improved leukocytosis, proteinuria was not sufficiently improved with combination therapy.  相似文献   
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Changes in brain pathology as schizophrenia progresses have been repeatedly suggested by previous studies. Meta-analyses of previous proton magnetic resonance spectroscopy (1H MRS) studies at each clinical stage of schizophrenia indicate that the abnormalities of N-acetylaspartate (NAA) and glutamatergic metabolites change progressively. However, to our knowledge, no single study has addressed the possible differences in 1H MRS abnormalities in subjects at 3 different stages of disease, including those at ultrahigh risk for psychosis (UHR), with first-episode schizophrenia (FES), and with chronic schizophrenia (ChSz). In the current study, 24 patients with UHR, 19 FES, 25 ChSz, and their demographically matched 3 independent control groups (n = 26/19/28 for the UHR, FES, and ChSz control groups, respectively) underwent 1H MRS in a 3-Tesla scanner to examine metabolites in medial prefrontal cortex. The analysis revealed significant decreases in the medial prefrontal NAA and glutamate + glutamine (Glx) levels, specifically in the ChSz group as indexed by a significant interaction between stage (UHR/FES/ChSz) and clinical status (patients/controls) (P = .008). Furthermore, the specificity of NAA and Glx reductions compared with the other metabolites in the patients with ChSz was also supported by a significant interaction between the clinical status and types of metabolites that only occurred at the ChSz stage (P = .001 for NAA, P = .004 for Glx). The present study demonstrates significant differences in 1H MRS abnormalities at different stages of schizophrenia, which potentially correspond to changes in glutamatergic neurotransmission, plasticity, and/or excitotoxicity and regional neuronal integrity with relevance for the progression of schizophrenia.Key words: anterior cingulate cortex, at-risk mental state, biomarkers, frontal lobe, magnetic resonance imaging, neurochemical abnormality  相似文献   
10.
The aim of this study was to evaluate the profile of dialyzability of an oral penem antibiotic, faropenem (FRPM), in hemodialysis (HD) patients with infections. Eight patients took one tablet of FRPM (200 mg) every 12 h during an inter‐dialysis period, and another tablet at 1–5 h before the beginning of the HD session. Blood samples were obtained during the HD session (3–4 h). Plasma FRPM concentrations in the arterial side were 4.8 ± 2.5 and 2.8 ± 1.0 µg/mL before and at the end of HD session, respectively, which are above the 50% minimal inhibitory concentrations of FRPM against the major pathogen (0.015–2 µg/mL). Dialyzer clearance and elimination fraction of FRPM were 14.9 ± 6.8 mL/min per m2 and 20.4 ± 9.9%, respectively. About 2% of FRPM was removed from the body during a single HD session. The infection‐related symptoms, the white blood cell count and the level of C‐reactive protein were improved by FRPM without any adverse effects. These data suggest that the dialyzability of FRPM is relatively low, and the amount of the drug removed by a single HD session is small. FRPM 200 mg twice daily might provide an effective and safe dosage regimen without additional dosing at the end of the HD session.  相似文献   
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