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781.
BACKGROUND: Due to their vasodilatory effect, calcium antagonist may have a renoprotective against cyclosporin (CsA)-induced nephrotoxicity and rise in blood pressure (BP) seen in renal transplantation. METHODS: In order to evaluate the effect of the calcium antagonist felodipine on renal function and BP during cyclosporin treatment, 79 CsA-treated renal transplant recipients were investigated during the first 3 months after transplantation in a randomized, double-blind, placebo-controlled study with two parallel groups. Felodipine (ER tablets, 10 mg) or placebo was given prior to transplantation and each day during the study period. The patients were assessed twice, i.e. at 4-6 weeks and at 10-12 weeks after transplantation. Renal plasma flow (RPF) and glomerular filtration rate (GFR) were measured by constant infusion technique. Tubular function was estimated from clearance of lithium. RESULTS: At 6 weeks after transplantation, felodipine caused a significantly higher RPF [felodipine: 219 +/- 70 ml/min; placebo: 182+/-56 ml/min (mean+/-1 SD); P=0.03]. No differences were found in GFR, filtration fraction (FF), tubular sodium handling, or sodium excretion. Felodipine lowered BP significantly. At 12 weeks after transplantation, felodipine caused a significantly higher GFR (felodipine: 49+/-18 ml/min; placebo: 40+/-16 ml/min; P=0.05) and RPF (felodipine: 225+/-77 ml/min; placebo: 175+/-48 ml/min; P<0.01). No difference was found in FF. Felodipine lowered BP significantly. No differences were found with regard to duration of primary anuria, hospitalization time, number of rejection episodes, plasma creatinine day 7 post-transplant, or treatment doses of CsA. CONCLUSIONS: It is concluded that in renal transplant recipients treated with CsA, felodipine significantly increased both GFR and RPF 3 months after transplantation when compared with placebo, despite a concomitant lowering of BP. A possible antagonizing affect of felodipine against CsA-induced nephrotoxicity in these patients is suggested. 相似文献
782.
M Glass RL Faull JY Bullock K Jansen EW Mee EB Walker BJ Synek M Dragunow 《Canadian Metallurgical Quarterly》1996,710(1-2):56-68
Using quantitative receptor autoradiographic methods we have examined A1 adenosine receptors, adenosine uptake sites, benzodiazepine receptors, NMDA, AMPA, and kainic acid receptors in temporal lobes removed from patients suffering from complex partial seizures and in normal control post-mortem temporal cortex. Binding to A1 adenosine receptors and NMDA receptors was reduced in epileptic temporal cortex, while the other neurochemical parameters were unchanged. The reason for this A1 receptor loss is unclear as it occurred in both idiopathic and symptomatic cases and thus may be a consequence rather than an initial cause of seizures. However, because adenosine is a powerful anticonvulsant substance, loss of anticonvulsant A1 receptors may contribute to the human epileptic condition. It is also possible that the observed differences in A1 binding are due to autopsy vs. biopsy changes in the levels of A1 adenosine receptors. 相似文献
783.
Disrupting bacterial biofilms is necessary for a wide application domains such as reusable medical devices, or systems of pipes for water or fluids in cosmetics, food and chemicals industry. Bacterial cells embedded in a biofilm are less susceptible to disinfectants than suspended cells. This property is referable to the structure of the biofilm itself. The gangue of exopolymers and the thickness of a 5-day-old biofilm of Escherichia coli (more than 200 layers of bacteria), contribute to this decrease of susceptibility. The present work deals with the release of an Escherichia coli biofilm by the sequential action of enzymes and a phenolic disinfectant on the one hand, and by the sequential or simultaneous action of surfactants and the previous disinfectant on the other hand. The decrease of bacteria count per mm2 and the Scanning Electron Microscope observations exhibited a synergic action in every case. Nevertheless, Escherichia coli biofilms quickly reconstructed even after exposition to the previous treatment. 相似文献
784.
785.
L-selectin is an adhesion molecule that mediates the recruitment of neutrophils to inflammatory sites and initiates the migration of lymphocytes into the peripheral lymph nodes. In response to cell activation, L-selectin is shed from the cell surface, and altered levels of functional soluble L-selectin are detected in the plasma of patients suffering from numerous inflammatory diseases as well as AIDS. The mechanism that regulates L-selectin shedding is poorly understood. Here we show that a hydroxamate-based metalloprotease inhibitor, N-(D,L-[2-(hydroxyaminocarbonyl)- methyl]-4-methylpentano)-L-3-(tert-butyl)-alanyl-L-alanine, 2-aminoethyl amide, which blocks leukocyte TNF, TNF receptor, and IL-6 receptor release, also inhibits L-selectin shedding from neutrophils, eosinophils, and lymphocytes. Moreover, we show that such inhibition of L-selectin shedding profoundly affects neutrophil aggregation and permits reaggregation in the presence of a heterologous stimulus. 相似文献
786.
The development of monoclonal antibodies and the emergence of recombinant DNA technology has made it possible to identify and selectively inhibit distinct cell subsets, surface molecules and secreted products that contribute to normal and pathological immune responses. These advances have helped to clarify the mechanisms that promote autoimmune diseases. As a result, it is now possible to contemplate rational strategies for the treatment of these diseases. Some of these strategies are designed to influence the cell surface interactions that determine whether potentially autoreactive T cells become activated or tolerant following antigen stimulation. Other strategies are designed to augment or inhibit distinct cytokines that regulate autoimmunity. All of these strategies have shown promise in animal models for systemic lupus erythematosus, and they may soon be translated into effective new therapies for people. 相似文献
787.
A series of 430 men aged 40 to 79 years underwent transrectal ultrasonography (TRUS) as part of a community survey of benign prostatic hyperplasia (BPH). We describe a reproducible method of prostate volume estimation and discuss the implications of prostate dimension changes in BPH. The mean prostate and adenoma volumes for the group were 32 ml (SD 14) and 15 ml (SD 11) respectively. The antero-posterior dimension of the prostate (APD) had the strongest correlation with gland volume compared with the transverse dimension (TD) and length (L). The mean ratio of adenoma volume to prostate volume was 0.45 (SD 0.13) and this increased with increasing gland volume. There was a modest correlation between the ratio and prostate volume. BPH is characterised by a proportionally greater increase in the APD compared with L and TD and by an increasing adenoma/prostate ratio. TRUS is useful in assessing the type and extent of adenoma and prostate enlargement in BPH. 相似文献
788.
DD Men'shikov EB Lazareva TS Popova LU Shramko IS Tokaev GV Zalogueva IN Gaponova 《Canadian Metallurgical Quarterly》1997,42(12):10-15
The influence of food fibres and plant proteins on microorganisms, bacteriophages, antibiotics and penicillinase was studied in vitro. It was shown that pectin was the only agent that had a bactericidal effect on the most widely distributed pathogenic and opportunistic microorganisms and did not influence indigenic microflora. High concentrations of pectin (> 2 per cent) had an inactivating effect on therapeutic bacteriophages. There was also a decrease in the antimicrobial activity of penicillins. The other agents tested i.e. wheat bran, soya isolate and soybean flour had no influence on microorganisms, bacteriophages and antibiotics. No sorption activity of the food fibres and plant proteins with respect to microorganisms and antibiotics or their effect on penicillinase was observed. 相似文献
789.
SV Joag I Adany Z Li L Foresman DM Pinson C Wang EB Stephens R Raghavan O Narayan 《Canadian Metallurgical Quarterly》1997,71(5):4016-4023
Chimeric simian/human immunodeficiency virus (SHIV) consists of the env, vpu, tat, and rev genes of human immunodeficiency virus type 1 (HIV-1) on a background of simian immunodeficiency virus (SIV). We derived a SHIV that caused CD4+ cell loss and AIDS in pig-tailed macaques (S. V. Joag, Z. Li, L. Foresman, E. B. Stephens, L. J. Zhao, I. Adany, D. M. Pinson, H. M. McClure, and O. Narayan, J. Virol. 70:3189-3197, 1996) and used a cell-free stock of this virus (SHIV(KU-1)) to inoculate macaques by the intravaginal route. Macaques developed high virus burdens and severe loss of CD4+ cells within 1 month, even when inoculated with only a single animal infectious dose of the virus by the intravaginal route. The infection was characterized by a burst of virus replication that peaked during the first week following intravenous inoculation and a week later in the intravaginally inoculated animals. Intravaginally inoculated animals died within 6 months, with CD4+ counts of <30/microl in peripheral blood, anemia, weight loss, and opportunistic infections (malaria, toxoplasmosis, cryptosporidiosis, and Pneumocystis carinii pneumonia). To evaluate the kinetics of virus spread, we inoculated macaques intravaginally and euthanized them after 2, 4, 7, and 15 days postinoculation. In situ hybridization and immunocytochemistry revealed cells expressing viral RNA and protein in the vagina, uterus, and pelvic and mesenteric lymph nodes in the macaque euthanized on day 2. By day 4, virus-infected cells had disseminated to the spleen and thymus, and by day 15, global elimination of CD4+ T cells was in full progress. Kinetics of viral replication and CD4+ loss were similar in an animal inoculated with pathogenic SHIV orally. This provides a sexual-transmission model of human AIDS that can be used to study the pathogenesis of mucosal infection and to evaluate the efficacy of vaccines and drugs directed against HIV-1. 相似文献
790.
We report a 24-year-old woman, her 6-year-old son and her 17-month-old daughter, who all suffer from a rare congenital genodermatosis first delineated by Huriez et al. in the 1960s. The clinical features of this autosomal dominant condition include scleroatrophy of the hands and feet, nail hypoplasia, mild palmoplantar keratoderma and hypohidrosis. Histological changes are non-specific, but immunohistological and ultrastructural examination in our index patient revealed an almost complete absence of epidermal Langerhans cells in the affected skin. This new finding may be linked to the cancer proneness of the scleroatrophic skin. In this family, the grandmother had died at the age of 37 years from metastatic squamous cell carcinoma which had arisen on the thenar eminence. 相似文献