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21.
A. Ueki L. Rosén B. Andbjer U. B. Finnman U. Altamimi A. M. Janson M. Goldstein L. F. Agnati K. Fuxe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,93(2):259-270
We studied the ability of the vigilance-promoting drug modafinil to modulate the anterograde and retrograde changes in tyrosine hydroxylase (TH) immunoreactivity and in dopamine (DA) stores in the nigro-neostriatal DA neurons, following a partial hemitransection of this ascending DA system, using a combined morphometrical, biochemical and behavioural analysis. Modafinil was given daily i.p. in doses of 10–100 mg/kg, starting 15 min after the lesion, and the partially hemitransected rats were killed 2 weeks later. Changes in TH-immunoreactive nerve cell bodies and nerve terminals induced by the partial hemitransection were studied in the substantia nigra and neostriatum in combination with image analysis. The substantia nigra and neostriatum were also subjected to biochemical analysis of DA, 3,4-dihydroxyphenylacetic acid and homovanillic acid levels. Modafinil treatment dose-dependently (10–100 mg/kg) counteracted the hemitransection-induced disappearance of nigral TH-immunoreactive nerve cell body profiles and neostriatal TH-immunoreactive nerve terminal profiles. A 2-week treatment with 100 mg/kg of modafinil also counteracted the hemitransection-induced depletion of DA stores in the neostriatum and the ventral midbrain. Moreover, the repeated daily treatment with modafinil (100 mg/kg) protected against the hemitransection-induced disappearance of striatal 5-hydroxytryptamine, 5-hydroxyindoleacetic acid and noradrenaline levels. Striatal DA function was analysed by studying apomorphine-induced (1 mg/kg, s.c.) ipsilateral rotational behaviour 4 and 11 days after the operation. A marked dose-dependent reduction of ipsilateral rotational behaviour was demonstrated after the daily modafinil treatment in the partially hemitransected rats. In another model involving unilateral nigral microinjections of 6-hydroxydopamine, acute (one single dose) modafinil (100 mg/kg) did not affect the contralateral rotational behaviour induced by apomorphine (0.05 mg/kg s.c.), when given 30 min before the apomorphine. Taken together, morphological, neurochemical and behavioural evidence has been obtained that anterograde and retrograde changes induced in the DA stores and TH immunoreactivity of the nigro-neostriatal DA neurons by a partial hemitransection are counteracted by modafinil in a dose dependent way with 100 mg/kg producing a significant protective action against impairment of DA transmission. The results of this study open up the possibility that modafinil may protect against the anterograde and retrograde degeneration of nigrostriatal DA neurons seen after mechanically induced injury. 相似文献
22.
Thoracic and retroperitoneal spindle-cell lesions represent a diagnostic challenge in the evaluation of fine-needle aspiration (FNA) specimens. The challenge is due to the morphologic similarities and wide variety of different entities with spindle-cell morphology in these two sites. The purpose of this study was to identify criteria helpful in the classification and differential diagnosis of spindle-cell lesions in these two locations. A set of cytologic features was analyzed in 57 thoracic or retroperitoneal spindle-cell lesions. Our results show that pleomorphism and abundant single cells were parameters associated with high-grade tumors in univariate and multivariate analysis, while coarse chromatin pattern was significant only in a univariate analysis. The combination of absence of pleomorphism, rare single cells, tight cluster arrangement, fine chromatin pattern, and absence of macronucleoli was seen only in benign cases. Assessment of background material was helpful in the differential diagnosis and classification. Necrosis was only found in high-grade cases. 相似文献
23.
Arbitrarily primed PCR, ribotyping, and plasmid pattern analysis applied to investigation of a nosocomial outbreak due to Enterobacter cloacae in a neonatal intensive care unit. 总被引:2,自引:8,他引:2 下载免费PDF全文
F Grattard B Pozzetto P Berthelot I Rayet A Ros B Lauras O G Gaudin 《Journal of clinical microbiology》1994,32(3):596-602
In December 1992, Enterobacter cloacae was isolated from the oropharynx and respiratory tract of six ventilated neonates hospitalized in the intensive care unit (ICU) of our hospital. To establish the spread of the outbreak, 41 strains of E. cloacae were analyzed for genotypic markers by three methods: plasmid profile analysis, ribotyping with EcoRI or PvuII endonuclease, and arbitrarily primed (AP) PCR. The tested strains included 12 isolates from the 6 epidemic cases, 4 isolates from the respiratory tract of 4 children hospitalized in other wards during the same period, 13 isolates from 12 children hospitalized in pediatric units before or after the outbreak, and 12 epidemiologically unrelated isolates. Ribotyping and AP PCR demonstrated that each of the last 12 strains exhibited distinct genomic patterns, as did each of the strains isolated from neonates hospitalized before or after the epidemic peak. Conversely, two clones of strains were found among the isolates recovered in December, with concordant results being obtained by the three typing methods: the first clone included seven strains from five ventilated children in the ICU and two children from another ward; another clone was shared by one neonate in the ICU and an infant from another ward. These results indicate that ribotyping and AP PCR-the latter applied, to our knowledge, for the first time to the genotypic analysis of E. cloacae--represent very discriminatory tools for the investigation of nosocomial outbreaks caused by this species. 相似文献
24.
A cell line producing monoclonal antibodies directed against the core region of Vibrio cholerae lipopolysaccharide has been established. These antibodies were inhibited by lipopolysaccharide preparations of both O-group 1 vibrios and some non-O-group 1 vibrios as detected in enzyme-linked immunosorbent assay-inhibition experiments. Coagglutination experiments with monoclonal and polyclonal antibodies adsorbed to protein A-carrying staphylococci were performed. All V. cholerae strains tested, regardless of serotype, were agglutinated when mixed with staphylococci coated with the monoclonal antibodies, whereas staphylococci coated with group-specific (O1) polyclonal antibodies only agglutinated with O-group 1 vibrios. 相似文献
25.
L Rosénstock P Demers N J Heyer S Barnhart 《Occupational and environmental medicine》1990,47(7):462-465
Although firefighters have been shown in some studies to suffer chronic respiratory morbidity from their occupational exposures, an increased risk for dying from non-malignant respiratory diseases has not been documented in any previous retrospective cohort mortality study. In order to assess the possibility that an unusually strong "healthy worker effect" among firefighters might mask this increased risk, a mortality analysis of firefighters was carried out in three cities in relation to the United States population and also to a comparison cohort of police officers. The firefighters were employed between 1945 and 1980 and experienced 886 deaths by 1 January 1984; compared with the United States population they had a significantly reduced risk of dying from all causes (SMR = 82, 95% confidence interval, 77-87), and from non-malignant circulatory diseases (SMR = 81, 95% confidence interval 73-89), but no significant difference in risk of non-malignant respiratory diseases (SMR = 88, 95% confidence interval 66-117). Compared with police, the firefighters experienced a trend toward improved mortality outcomes for all causes investigated (SMR = 82), but they had an excess of deaths from non-malignant respiratory diseases (SMR = 141). The results indicate that firefighters are probably at increased risk for dying from non-malignant respiratory diseases; this increased risk may have been missed in previous studies because of the limitations of using a general reference population. 相似文献
26.
Rosário Filho NA Pachaly MA Miasaki N Kantor Júnior O Schmitt-Lobe MC Nesi S 《Jornal de pediatria》1995,71(4):223-226
Increased sweat concentrations (92, 76 and 80 mEq/l) were observed in a 7-year-old boy with pitressin-resistant diabetes insipidus. All previous observations of elevated sweat electrolytes in diabetes insipidus have been in infants less than 10 months of age. The sweat test is an exceptionally reliable, sensitive and specific test for the diagnosis of Cystic Fibrosis. Pitressin-resistant diabetes insipidus is one of the diseases associated with elevated sweat test results. 相似文献
27.
Heiko Kilter Olaf Lenz Karl La Rosée Markus Flesch Robert H. G. Schwinger Martin Mädge Ferdinand Kuhn-Regnier Michael Böhm 《Naunyn-Schmiedeberg's archives of pharmacology》1995,352(3):308-312
Nitric oxide (NO) has been reported to mediate several effects in response to muscarinic cholinergic stimulation in cardiovascular tissues. Recently, an attenuation of guinea pig cardiac myocyte contraction by NO has been described. The aim of the present study was to determine whether the indirect negative inotropic effect of M-cholinoceptor stimulation in human myocardium is in part due to an effect of endogenous NO. Therefore, the effect of carbachol was studied under control conditions and during inhibition of NO-synthase by pretreatment with NG-monomethyl-l-arginine (NMMA). Functional experiments were performed in isolated, electrically driven (1 Hz, 37°C) left ventricular papillary muscle strips of human myocardium. Since cytokines have been reported to be increased in the serum of patients with heart failure and could induce NO-synthase activity in failing myocardium, we compared samples from nonfailing and terminally failing (classified as NYHA IV) hearts. The indirect negative inotropic effect of carbachol (10 mol/l) was studied in the presence of the \-adrenoceptor agonist isoprenaline (0.03 mol/l).After stimulation with isoprenaline, carbachol significantly (P < 0.05) reduced force of contraction. This effect was diminished in failing myocardium compared to nonfailing, probably due to the diminished inotropic response most likely due to the lower cAMP levels in response to \-adrenoceptor stimulation in the former condition. Pretreatment with NMMA (100 mol/l) altered the antiadrenergic effect of carbachol neither in nonfailing nor in failing preparations. Furthermore, inhibition of guanylyl cyclase, the target enzyme of NO, by preincubation with methylene blue (10 mol/l) for 30 min had no effect on the carbachol-induced decrease in force of contraction. Basal force of contraction, as well as the positive inotropic effect of isoprenaline remained unaffected by NMMA or methylene blue.The present study provides evidence that the indirect negative inotropic effect of M-cholinoceptor agonists is not due to an effect of NO in the human myocardium. Furthermore, the well known enhancement of cGMP in response to M-cholinoceptor stimulation appears not to be involved in this antiadrenergic effect. 相似文献
28.
Ramírez-Tortosa C López-Pedrosa JM Suarez A Ros E Mataix J Gil A 《The British journal of nutrition》1999,82(1):31-39
The present study describes a clinical trial in which Spanish patients suffering from peripheral vascular disease (Fontaine stage II) were given specific lipid supplements. Designed as a longitudinal intervention study, patients were provided with olive oil for 3 months, followed by a 3 month wash-out period, then supplemented with a combination of fish oil and olive oil for the final 3 months. Changes in plasma and lipoprotein fatty acid composition and susceptibility of LDL to in vitro oxidation were examined. Furthermore, lipid-supplement-induced changes in LDL properties were measured as relative electrophoretic mobility and macrophage uptake. In addition, thirteen patients not provided with olive oil and fish oil were included as a control group and twenty healthy age-matched individuals were used as a reference group. A complete clinical study and a nutritional survey concerning food habits and lifestyle were performed every 3 months. Yao indices and claudicometry did not change significantly with dietary intervention although changes in plasma lipid composition suggested an improvement in the condition of the patients. The intake of the fish-oil supplement resulted in significantly increased plasma levels of eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) in comparison with baseline concentrations, olive-oil and control groups. Fish-oil consumption significantly decreased plasma triacylglycerol levels compared with the olive-oil period, control and reference groups. The susceptibility of LDL to Cu-mediated oxidation was lower in the patients consuming olive oil and the fish-oil supplement than in the control group, and the uptake of LDL by macrophages was significantly lower in the group supplemented with fish oil. In conclusion, consumption of olive oil together with a dietary supplement of fish oil may be useful in the nutritional management of patients suffering from peripheral vascular disease in terms of increasing plasma n-3 long-chain polyunsaturated fatty acids and decreasing susceptibility of LDL to oxidation. 相似文献
29.
Tamoxifen versus placebo in the treatment of Peyronie's disease 总被引:3,自引:0,他引:3
Teloken C Rhoden EL Grazziotin TM Ros CT Sogari PR Souto CA 《The Journal of urology》1999,162(6):2003-2005
PURPOSE: We evaluated the effects of oral tamoxifen and placebo in patients with Peyronie's disease. MATERIALS AND METHODS: We selected 25 patients with Peyronie's disease who did not have calcified plaque for treatment in the andrology outpatient clinic. A medical history was obtained, and physical examination, penile x-ray, penile ultrasound and pharmacologically induced erection with prostaglandin E1 were performed. Patients were randomly divided into group 1--those who received 20 mg. tamoxifen twice daily for 3 months and group 2--those who received placebo for the same period. The same evaluations were done 4 months later and results were compared. Qualitative (chi-square test) and quantitative (Student's t test) results were analyzed using the Yates correction factor with p <0.05 considered significant. RESULTS: Pain subsided in 66.6 and 75% of the patients treated with tamoxifen and placebo, respectively (p >0.05). In groups 1 and 2 a reduction in the penile deformity was noticed by 46.1 and 41.7% of the patients (p >0.05), and a decrease in plaque size was noticed by 30.7 and 25%, respectively. On the other hand, objective measurements did not reveal any difference in plaque area or curvature angle. CONCLUSIONS: This study did not show significant improvement in pain, curvature or plaque size in patients with Peyronie's disease who were treated with tamoxifen compared with those treated with placebo. 相似文献
30.
Navas Pastor J Ferrero Doria R Guzmán Martínez-Valls PL Morga Egea JP García Ligero J Tomás Ros M Rico Galliano JL Sempere Gutiérrez A Fontana Compiano LO 《Actas urologicas espa?olas》1999,23(1):22-27
Presentation of eight cases of urinary candidiasis in patients who underwent radical cystectomy and were managed using by-pass of the urinary tract, oral antifungal therapy and solutions in the way of intermittent instillation through nephrostomy catheters. 相似文献