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41.
Pharmacokinetics of prednisolone in children with the nephrotic syndrome   总被引:1,自引:0,他引:1  
The aim of this study was to establish whether the criteria for the clinical effectiveness of steroids are correlated with the pharmacokinetics of prednisolone in children treated with prednisone during an attack of idiopathic nephrotic syndrome (INS). Thirteen patients with nephrosis were included. Prednisolone, prednisone and cortisol levels were measured using a specific high-performance liquid chromatography assay after an oral dose of 1 mg/kg body weight of prednisone taken at the onset of the disease. All the pharmacokinetic parameters, including the conversion of prednisone to prednisolone were similar to the data already published in children with INS. No correlation was found between the values of pharmacokinetic parameters and criteria of clinical effectiveness. Hypo-albuminaemia was significantly correlated with the area under the plasma-concentration curve but not with the elimination half-life of prednisolone. Moreover, the prednisolone elimination half-life correlated with the urinary exretion of 17-hydroxycorticosteroids achieved in the first 6h. The present study suggests that routine measurements of prednisolone kinetics do not help when assessing the treatment of children with INS.  相似文献   
42.
Myofibroblasts and the progression of diabetic nephropathy   总被引:23,自引:3,他引:20  
Background. The cellular mediators of progressive renal fibrosis in diabetic nephropathy remain unknown. Myofibroblasts have been implicated in the pathogenesis of experimental and clinical renal fibrosis. Their role in the progression of diabetic nephropathy is the subject of this study.Subjects and methods. We have studied by immunohistochemistry the expression of cytoskeletal proteins associated with the activation of myofibroblasts; &agr;-smooth-muscle actin (&agr;-SMA), vimentin (Vi) and desmin (D), in the kidneys of 25 patients with diabetic nephropathy (5 patients with diabetic nephropathy (5 patients had a superimposed glomerulonephritis). Comparisons were made with normal tissue for three kidneys removed for renal-cell carcinoma. Correlations were studied between clinical and biochemical parameters with the expression renal cytoskeletal proteins. Results. In normal kidneys, cells expressing &agr;-SMA were confined to the vascular media and adventia while immunoreactive Vi was detected in glomerular epithelial cells. In diabetic kidneys, cells expressing &agr;-SMA were detected primarily in the renal interstitium and to a lesser extent in some glomeruli in association with mesangial proliferation. Vimentin immunostain decreased in glomeruli displaying diabetic hyalinosis and sclerosis. By contrast, strong Vi immunoreactivity was noted in atrophic diabetic tubules and to a lesser extent in the interstitium. Desmin was not detected in either normal or diabetic kidneys. Close correlations were observed between the expression of renal cytoskeletal proteins and the progression of renal insufficiency. Interstitial &agr;-SMA proved to be a predictor of progressive diabetic nephropathy (R2 for 1/serum Cr slope=0.608, P=0.00001). This predictive parameters; tubular atrophy (R2=0.477, P=0.00004) and interstitial fibrosis (R2=0.28, P=0.001). Conclusion. We have demonstrated in this study the neoexpression of cytoskeletal proteins within diabetic kidneys. This has allowed the identification of new predicting histological markers for the progression of diabetic nephropathy.  相似文献   
43.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
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BACKGROUND: Conventional depot antipsychotics can provide constant pharmacologic treatment, eliminating partial compliance and reducing relapse risk. Atypical antipsychotics, have improved clinical profiles but require daily dosing, compromising their overall effectiveness. As oral risperidone provides safety and efficacy benefits over oral haloperidol, improvements may be realized by replacing conventional with atypical agents in long-acting therapy. This report examines 50-weeks of long-acting risperidone therapy in patients previously stabilized with conventional depot antipsychotics. METHODS: A multi-center, open-label study enrolled 725 patients with schizophrenia or schizoaffective disorder, judged clinically stable and maintained on stable antipsychotic doses for > or =4 weeks. Assignment by clinician judgment to receive 25-75 mg of long-acting risperidone every 2 weeks for 50 weeks followed, with performance of standard safety and efficacy assessments. Data are presented on patients receiving conventional depot antipsychotic monotherapy at study entry. RESULTS: In the 188 (25.9%) patients receiving conventional depot antipsychotic monotherapy at entry, mild-to-moderate mean (+/-S.D.) Positive and Negative Syndrome Scale (PANSS)-total scores improved significantly after receiving long-acting risperidone (64.2 +/- 18.9 to 58.2 +/- 20.3; P < 0.001). Clinical improvement of > or =20%, 40%, or 60% reduction in PANSS-total score, occurred in 52%, 34%, and 16% of patients, respectively. ESRS subjective ratings and objective physician ratings (Parkinsonism) decreased significantly (P < 0.001). CONCLUSION: Stable patients with mild, residual symptomatology treated with conventional depot antipsychotics experienced significant improvement in psychiatric and movement disorder symptomatology following 1-year of treatment with long-acting risperidone.  相似文献   
47.
BACKGROUND: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures. METHODS: The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients' self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded. RESULTS: The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa=.47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa=.2), and 37% underreported when using the CDT+GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption. CONCLUSION: This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.  相似文献   
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The purpose of this study was to determine the nature and amounts of prostaglandins (PGs) produced by squamous carcinoma cells (SCC) and the sensitivity of these cells to non-steroidal anti-inflammatory drugs. SCC of four lines of the tongue and one line of facial epidermis of humans were incubated in phosphate buffer solution with 14C-arachidonic acid (AA). Radioactive metabolites in aqueous methanol were chromatographed on Sep-Pack CIS cartridges, separated and quantitated by means of TLC, autoradiography, and liquid scintillation counting. The results showed that cyclooxygenase products, PGs, were the major products formed by all cell lines, and PGE2 was predominant among the PGs detected. Two radioactive bands corresponding to PGF and three unseparated standards of PGA2, 15-keto-PGE2, and 13,14-dihydro-15-keto-PGE2were detected in lesser amounts. Very small amounts of the lipoxygenase products 12-and 15-HETE were found. The concentrations of indomethacin, ibuprofen and aspirin required to inhibit 50% of PGE2 synthesis (IC50) by SCC lines were .008- .080, .080–6.4 and 32–88 μM, respectively.  相似文献   
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