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131.
Multiple sclerosis (MS) is a T-cell-mediated autoimmune demyelinating disease of the central nervous system (CNS), associated with an altered immunoregulation. Interferon (IFN)-, also known as immune IFN, is a cytokine with several effects on the immune system. Specific IFN- receptors have been found on human lymphocytes, as well as on other cell types (e.g. gliocytes), even in the CNS. The aim of the present study was to evaluate IFN- binding on peripheral blood T-lymphocytes from MS patients, compared with those from healthy subjects. Thirty-two patients were selected according to the classical criteria for definite MS; as controls, 21 healthy subjects were studied. We have found that T-lymphocytes from MS patients bear a significantly smaller amount of IFN- receptors than those from controls [B max: 568, 18 vs 708, 14 (mean, SE) receptors/cell]. Such IFN- binding sites are of the same type in patients and healthy subjects [K d: 1.0, 0.05 vs 0.9, 0.02 (mean, SE) nM]. These findings are discussed in terms of immunopathogenesis of MS, since it has been reported that activated T-lymphocytes have decreased amounts of IFN- receptors.  相似文献   
132.
We evaluated the adverse reactions (AR) rate produced in patients to see if any difference related to the diferent chemotoxicities of two low-osmolality contrast media (CM), could be detected. We compared the AR rate intravenous administration for brain or body computed tomography (CT) enhancement of either the ionic CM ioxaglate 320 mgI/ml or the non-ionic iopamidol 300 mgI/ml at a dose of 0.8 gI/kg. Three hundred and thirty patients (164 ioxaglate, 166 iopamidol) were studied according to a randomized double-blind design. AR reported by the patients (subjective) and/or observed by the radiologist (objective) were recorded by the radiologist on the patients record card. Laboratory test were performed prior to and 24 h after contrast administration.Fifty-nine mild to moderate AR occurred in 30 patients (18.3%) receiving ioxaglate, 4 mild to moderate AR occurred in 2 patients (1.2%) receiving iopamidol (P < 0.05). No severe AR occurred in either group.The results of our study are comparative to the available evidence from 16 comparative randomized trials of iopamidol versus ioxaglate both after intraarterial and intravenous administration that gave an overall odds ratio of 3.9 [confidence interval (CI) 95% = 3.1–4.9].The diagnostic efficacy of the two CM was comparable. This study showed that the non-ionic CM iopamidol was better tolerated than the ionic ioxaglate after intravenous administration. We conclude that the chemotoxicity of the molecule influences the AR when CM with comparable osmolality are administered. Correspondence to: Carlo Del Favero  相似文献   
133.
134.
In 12 patients affected by thalassemia major who received an intensive transfusion regimen combined with continuous iron chelation therapy (desferrioxamine 50–80 mg/kg daily), radiologic abnormalities of the long bones were observed similar to those observed in rickets and scurvy. These abnormalities were associated with a growth retardation. The pathogenesis of these lesions is uncertain, but probably the toxic effect of desferrioxamine plays an important role in their development. A relative deficiency of vitamins D and/or C cannot be entirely excluded.  相似文献   
135.
Summary Three families are described which include members with typical Friedreich's disease (FD) and others who are ataxic but do not satisfy all the diagnostic criteria for that disease. In family A two patients have an early-onset, rapidly progressive FD, while two others have a late-onset, more benign form. In families B and C one member has typical FD, and another has a similar ataxic syndrome, except for preservation of knee jerks. Laboratory evaluation is consistent with the diagnosis of FD in all cases. FD diagnosis appears justified in secondary cases with late onset or preserved tendon reflexes, provided that the index case fulfils all diagnostic criteria. Whether the diagnosis of FD is tenable in sporadic atypical cases remains to be seen. Echocardiographic and neurophysiological examination may be valuable in classifying such cases.  相似文献   
136.
Summary In order to investigate whether a chronic impairment of neuronal serotoninergic transmission in the CNS could result in a receptor supersensitivity, rabbits were pretreated either with 5,6-dihydroxytryptamine (5,6-DHT) or p-chlorophenylalanine (PCPA) and then tested for their hyperthermic response to serotoninergic agonists.A previous (10 days before) intracerebroventricular injection of 5,6-DHT (75 g into each cerebral ventricle) significantly potentiated the increase in body temperature induced either by quipazine (1 mg/kg i.v.) or by 5-hydroxytryptophan (5-HTP 2 mg/kg i.v.) in combination with a MAO inhibitor (phenylethylhydrazine 10 mg/kg i.v. 16 h before). Pretreatment with PCPA (100 mg/kg s.c. four times on alternate days, the last dose 48 h before the experiment) also enhanced the hyperthermic effect of quipazine, whereas it inhibited the hyperthermic response to 5-HTP plus MAO inhibitor.These results suggest the exstence of a receptor supersensitivity following prolonged blockade of serotoninergic neuronal transmission in the CNS.Supported by C.N.R. grant n. 75.00620.04.115.2380  相似文献   
137.
The Authors compare the results obtained between two groups of patients suffering from leg lipodystrophy, who were subjected to a reducing lipoplasty. In the first group, surgeons made use of a new sort of cannula, deprived of the classical grip, whereas in the second group, they employed the traditional probe. The best results, achieved with the first group, prove this new operating system is really effective, particularly on legs, for the following reasons: (1) Higher precision and better control of the instrument (2) Swan-neck cannula abolition (3) Opportunity to operate with both hands (4) Halved operating time (5) No tiredness after the operation.  相似文献   
138.
Here, we summarize recent data pertaining to the effects of GABAA receptor modulators on the receptor gene expression in order to elucidate the molecular mechanisms behind tolerance and dependence induced by these drugs. Drug selectivity and intrinsic activity seems to be important to evidence at the molecular level the GABAA receptor tolerance. On the contrary, we suggested that all drug tested are equally potentially prone to induce dependence. Our results demonstrate that long-lasting exposure of GABAA receptors to endogenous steroids, benzodiazepines and ethanol, as well as their withdrawal, induce marked effects on receptor structure and function. These results suggest the possible synergic action between endogenous steroids and these drugs in modulating the functional activity of specific neuronal populations. We report here that endogenous steroids may play a crucial role in the action of ethanol on dopaminergic neurons.  相似文献   
139.
PURPOSE: To investigate potential immunotherapeutic strategies in B lymphocytic malignancies we looked for CTLs recognizing CD19 and CD20 epitopes. EXPERIMENTAL DESIGN: Three CD19 and CD20 peptides binding to HLA-A*0201 were identified and used to detect peptide specific CTLs by a quantitative real-time PCR to measure IFN-gamma mRNA expression in 23 healthy individuals and 28 patients (18 chronic lymphocytic leukemia (CLL), 7 follicular lymphoma, 2 acute lymphocytic leukemia, and 1 large cell lymphoma). Peptide-specific CTLs were expanded in culture with CD40-activated B cells to test lytic activity in three patients. RESULTS: In healthy individuals, CD8+ T-cell responses were detected in one to CD19(74-82), in three to CD20(127-135), and three to CD20(188-196). Seven of 27 patients (6 with CLL) had CD8+ T cells recognizing CD19(74-82). Seven patients responded to CD20(127-135) and three to CD20(188-196). All were CLL patients. CD19(74-82)-specific CTLs from three patients were expanded over 4 weeks. These cells were HLA-A*0201 specific and lytic for peptide-loaded antigen-presenting cells but not to malignant or unpulsed B cells. CONCLUSIONS: CTLs that recognize CD19 and CD20 epitopes exist in healthy individuals and may be increased in CLL patients. They are of low avidity and require high doses of peptide for activation. Strategies to increase T-cell avidity would be necessary for T-cell immunotherapeutic approaches using the peptides studied.  相似文献   
140.
PURPOSE: Preclinical studies indicate that gefitinib (Iressa, ZD1839; AstraZeneca, Wilmington, DE), an orally active epidermal growth factor receptor tyrosine kinase inhibitor, may enhance antitumor efficacy of cytotoxics, and combination with paclitaxel and carboplatin had acceptable tolerability in a phase I trial. Gefitinib monotherapy demonstrated unparalleled antitumor activity for a biologic agent, with less toxicity than docetaxel, in phase II trials in refractory, advanced non-small-cell lung cancer (NSCLC). This phase III, randomized, placebo-controlled, double-blind trial evaluated gefitinib plus paclitaxel and carboplatin in chemotherapy-naive patients with advanced NSCLC. PATIENTS AND METHODS: Patients received paclitaxel 225 mg/m(2) and carboplatin area under concentration/time curve of 6 mg/min/mL (day 1 every 3 weeks) plus gefitinib 500 mg/d, gefitinib 250 mg/d, or placebo. After a maximum of six cycles, daily gefitinib or placebo continued until disease progression. End points included overall survival, time to progression (TTP), response rate (RR), and safety evaluation. Results A total of 1,037 patients were recruited. Baseline demographic characteristics were well balanced. There was no difference in overall survival (median, 8.7, 9.8, and 9.9 months for gefitinib 500 mg/d, 250 mg/d, and placebo, respectively; P =.64), TTP, or RR between arms. Expected dose-related diarrhea and skin toxicity were observed in gefitinib-treated patients, with no new significant/unexpected safety findings from combination with chemotherapy. Subset analysis of patients with adenocarcinoma who received > or = 90 days' chemotherapy demonstrated statistically significant prolonged survival, suggesting a gefitinib maintenance effect. CONCLUSION: Gefitinib showed no added benefit in survival, TTP, or RR compared with standard chemotherapy alone. This large, placebo-controlled trial confirmed the favorable gefitinib safety profile observed in phase I and II monotherapy trials.  相似文献   
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