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71.
Mice lacking alpha-synuclein have an attenuated loss of striatal dopamine following prolonged chronic MPTP administration 总被引:1,自引:0,他引:1
The functional role of alpha-synuclein in the pathogenesis of Parkinson's disease (PD) is not fully understood. Systemic exposure of alpha-synuclein-deficient mice to neurotoxins provides a direct approach to evaluate how alpha-synuclein may mediate cell death in a common murine model of PD. To this end, wild-type and homozygous alpha-synuclein knock-out mice were treated with sub-chronic and prolonged, chronic exposure to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). In the sub-chronic model, wild-type and alpha-synuclein knock-out mice were treated for five consecutive days with MPTP (1-25 mg/kg, s.c.) or vehicle, and sacrificed 3 days following the last injection. The prolonged, chronic model consisted of two injections of MPTP (1-20 mg/kg, s.c.) per week for 5 weeks, with co-administration of probenecid (250 mg/kg, i.p.), and animals were sacrificed 3 weeks following the last injection. Sub-chronic administration of MPTP caused a dramatic, dose-dependent decrease in striatal dopamine (DA) concentrations, while an attenuated response was observed in alpha-synuclein knock-out mice. Similarly, prolonged, chronic administration of MPTP produced a dose-dependent decrease in striatal DA concentrations, and a corresponding loss of striatal vesicular monoamine transporter (VMAT-2) protein in wild-type mice. However, mice lacking alpha-synuclein had an attenuated loss of striatal DA concentrations, while no loss of striatal VMAT-2 protein was observed. Both sub-chronic and prolonged, chronic administration of MPTP caused an increase in the 3,4-dihydroxyphenylacetic acid (DOPAC) to DA ratio in wild-type mice, but not in mice lacking alpha-synuclein. Despite attenuated toxicity, elevated lactate concentrations were observed in alpha-synuclein knock-out mice following prolonged, chronic MPTP administration. The results of this study provide evidence that alpha-synuclein null mice have an attenuated response to the toxic effects of MPTP exposure, even over prolonged periods of time and that the biochemical sequela of a protracted insult to nigrostriatal DA neurons are distinct between mice with and without alpha-synuclein expression. 相似文献
72.
Kassaï B Boissel JP Cucherat M Sonie S Shah NR Leizorovicz A 《Thrombosis and haemostasis》2004,91(4):655-666
Evaluation of the accuracy of ultrasound has yielded heterogeneous results. Our objective was to summarize the evidence on the accuracy of ultrasound compared to venography in asymptomatic patients, taking into account the variation due to threshold differences. Searches of journal table of contents, computer databases (Medline, Embase, Biomed, Cochrane) and conference proceedings were performed. A study was eligible if it prospectively compared ultrasound to venography for the diagnosis of DVT in asymptomatic patients. Data of studies selected for inclusion were extracted independently by two authors. High quality studies with consecutive patient enrollment, blind evaluation of the two techniques, and absence of verification bias are summarized as Level 1, while those not fulfilling one or more of these criteria are considered Level 2. Original study authors were contacted to confirm accuracy and to provide missing data. A pooled estimate of the accuracy of ultrasound was obtained according to the method of Moses and coworkers. This method gives a summary diagnostic odds ratio (DOR). The DOR is a single indicator of test performance. It varies between 0 and infinity and exceeds 1, only when ultrasound is more often positive in patients with DVT relative to those without DVT. Higher DOR indicates better discriminatory test performance. Thirty one studies were rated as potentially unbiased and graded as Level 1. The mean prevalence of DVT as determined by venography was 22%. In Level 1 studies, the odds of positive ultrasound in proximal veins was 379 times higher (95% confidence limits 65, 2,200) and in distal veins 32 times higher (7.5, 135) among patients with DVT than those without. Our results suggest that, particularly for proximal veins, ultrasound is accurate for the diagnosis of DVT in asymptomatic postoperative orthopedic patients. More research is needed in other clinical settings. 相似文献
73.
Kheradvar A Tabassi AR Nikbin B Khosravi F Naroueynejad M Moradi B Amirzargar AA 《Multiple sclerosis (Houndmills, Basingstoke, England)》2004,10(5):526-531
BACKGROUND: Genetic predisposition in multiple sclerosis (MS) has always been a critical concern in aetiology and progress of the disease. The present study looks into the relations between human leukocyte antigen (HLA), optic neuritis (ON) and MS in the Iranian population. METHODS: Patients with potential diagnosis of acute ON underwent a standardized clinical examination for confirming the diagnosis. Selected patients were gathered for HLA typing and clinical follow up. RESULTS: Of the 55 patients, 46 (83.6%) were female. The mean age was 25(+/-7.3) with a range of 12-43. Twenty of the 55 (36%) were confirmed for the diagnosis of clinically definite MS (CDMS). Results show that A23, B21, A11 and B51 alleles were present in 4 (20%), 6 (30%), 2 (10%) and 1 (5%) of the CDMS patients, respectively. Ten (50%) and 17 (85%) CDMS patients were positive for HLA class II alleles, DR2 and DQ1, correspondingly. CONCLUSIONS: The study strongly suggests the association among DR2, A23 and B21 allele and the evolution of ON to MS. High prevalence of A23 and DR2 alleles in CDMS patients compared with the normal population may suggest an important role for these alleles in the development of MS. The study suggests B51 as a protective factor against development of ON in the normal population. In addition, results do not confirm previous studies considering A11 as a predisposing factor. The present study finally evokes that different classes of HLA have different roles in susceptibility to MS and confirms disease heterogeneity as an important emerging concept in MS. 相似文献
74.
Metzger WG Mansouri E Kronawitter M Diescher S Soerensen M Hurwitz R Bumann D Aebischer T Von Specht BU Meyer TF 《Vaccine》2004,22(17-18):2273-2277
Orally administered recombinant Salmonella vaccines represent an attractive option for mass vaccination programmes against various infectious diseases. Therefore, it is crucial to gather knowledge about the possible impact of preexisiting immunity to carrier antigens on the immunogenicity of recombinant vaccines. Thirteen volunteers were preimmunized with Salmonella typhi Ty21a in order to evaluate the effects of prior immunization with the carrier strain. Then, they received three doses of 1-2 x 10(10) viable organisms of either the vaccine strain S. typhi Ty21a (pDB1) expressing subunits A and B of recombinant Helicobacter pylori urease (n = 9), or placebo strain S. typhi Ty21a (n = 4). Four volunteers were preimmunized and boosted with the vaccine strain S. typhi Ty21a (pDB1). No serious adverse effects were observed in any of the volunteers. Whereas none of the volunteers primed and boosted with the vaccine strain responded to the recombinant antigen, five of the nine volunteers preimmunized with the carrier strain showed cellular immune responses to H. pylori urease (56%). This supports the results of a previous study in non-preimmunized volunteers where 56% (five of nine) of the volunteers showed a cellular immune response to urease after immunisation with S. typhi Ty21a (pDB1). 相似文献
75.
Belaabidia B Essadki O el Mansouri A Squalli S 《Gynécologie, obstétrique & fertilité》2002,30(5):383-389
AIM OF THE STUDY: The authors report eight cases of idiopathic granulomatous mastitis in which the epidemiological, clinical, diagnostic, therapeutic and prognostic features are discussed. MATERIAL AND METHODS: Retrospective study of eight cases registered among 2,000 breast anatomopathological study during 5-years period. RESULTS: The mead age was 44.3 years. Breast lump measuring 2.5 to 15 cm in size was noted at clinical examination. Mammography noted nodular opacities and ultrasonography showed hypoechoic nodules. Histological findings were consistent on granulomatous inflammation centred on mammary lobules. The inflammatory infiltrate was including leukocytes, lymphocytes, plasma cells as well as epithelioid and giant cells without caseous necrosis in the granuloma. DISCUSSION AND CONCLUSION: Idiopathic granulomatous mastitis is a rare entity. This entity can clinically mimic other breast mastitis disease. Diagnosis is assessed by histological analysis This disease can be treated with drugs and surgical excision of the lump. The prognostic of this chronic disease is favourable. 相似文献
76.
Zandieh Doulabi B Platvoet-ter Schiphorst M van Beeren HC Labruyere WT Lamers WH Fliers E Bakker O Wiersinga WM 《Endocrinology》2002,143(3):979-984
We investigated the distribution and diurnal variation of TR(beta)1 protein expression in liver with specific antibodies against TR(beta)1. Immunohistochemistry showed a zonal distribution of TR(beta)1 with maximum expression in the pericentral zone matching some known T(3)-responsive enzyme activities in the liver, such as glutamine synthetase, cholesterol 7alpha- hydroxylase, and spot 14. Combining immunohistochemistry and image analysis we found and quantified the same zonal distribution for 5'-deiodinase type 1 as for TR(beta)1. Western blot analysis revealed a profound diurnal variation for TR(beta)1 protein expression, with highest levels at the beginning of the dark period. TR(beta)1 diurnal variation partly overlaps with the T(3)-responsive genes, cholesterol 7alpha-hydroxylase and spot 14. Furthermore, TR(beta)1 distribution along the porto-central axis does not change during the day, indicating that the zonal expression of TR(beta)1 is stable. This is the first time that zonal distribution in liver has been demonstrated for a member of the nuclear receptor family. This finding together with the observed diurnal rhythm has major implications for interpreting and timing experiments concerning the TR and its downstream actions in liver. 相似文献
77.
Foroumadi A Mansouri S Kiani Z Rahmani A 《European journal of medicinal chemistry》2003,38(9):851-854
A series of N-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-yl]piperazinyl quinolones (7a-c) were synthesized and evaluated for in vitro antibacterial activity against some Gram-positive and Gram-negative bacteria. The antibacterial data revealed that compounds 7a-c had strong and better activity against tested Gram-positive organisms than the reference quinolones such as ciprofloxacin, norfloxacin and enoxacin. However, all three compounds were nearly inactive against Gram-negative bacteria. Compound 7a (ciprofloxacin analogue) was the most active compound against Gram-positive bacteria (MIC=0.008-0.015 mug mL(-1)). 相似文献
78.
Kanouni L Kebdani T El Ghazi EA El Mostarchid B Amarti A Mansouri A Errihani H Benjaafar N El Gueddari BK 《Neuro-Chirurgie》2003,49(1):39-43
We report the case of a 50-year-old woman presenting a primitive adenoid cystic carcinoma of the middle part of skull base diagnosed by transphenoidal biopsy. She was treated by exclusive radiation therapy with cobalt 60 1.25 MeV and the dose received was 66 Gy in 33 fractions. Our patient remains alive 50 months after the completion of treatment. Adenoid cystic carcinoma is a slow growing malignant tumor with perineural invasion which arises more frequently from salivary glands. The occurrence of primary intracranial adenoid cystic carcinoma is exceptional. The best treatment is radical surgery followed by radiotherapy. Chemotherapy is rarely used. Prognosis is worse than for salivary glands. 相似文献
79.
Yari F Hosseini AZ Nemat-Gorgani M Sareh S Khorramizadeh MR Mansouri P Nejad AK 《Hybridoma and hybridomics》2003,22(5):301-306
Production of monoclonal antibodies to HLA-G, a nonpolymorphic antigen of non-classical HLA class I, is of basic and clinical importance. In the present study, monoclonal antibodies were prepared which recognize different membrane bound and soluble isoforms of HLA-G, following immunization of BALB/c mice with a synthetic peptide. Use of this peptide (23 residues), which is present in the alpha1 domain of HLA-G, was previously demonstrated to provide antibodies useful for recognition of HLA-G isoforms in human placenta. Antibody-producing hybridomas were screened by an indirect one-step ELISA method. A clone designated 5E6H7, secreted antibodies useful in immunostaining studies involving both surface HLA-G of placental tissues and soluble forms of this antigen in human sera. In addition, unreactivity of this antibody with human lymphocytes and sections of normal human skin was observed by immunofluorescence microscopy, thus demonstrating its specificity for HLA-G. 相似文献
80.