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The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
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BACKGROUND: The present study was aimed to define the gender ratio, familial occurrence, age of onset, precipitating factors, clinical types, nail and joint involvement of psoriasis in childhood and adolescence in Turkey. METHODS: A total of 61 children with psoriasis under 18 years old were evaluated retrospectively, for age, gender, age of disease onset, family history, concomitant disease, the clinical type of psoriasis, clinical localization, nail and joint involvement and treatment modalities. RESULTS: Of the patients, 23 (37.70%) were boys and 38 (62.30%) were girls. Mean age was 9.28 +/- 4.02 years in girls and 11.18 +/- 3.85 years in boys (9.96 +/- 4.03 years in all children). Mean age at the onset of the disease was 6.81 +/- 4.11 years in girls and 7.03 +/- 4.28 years in boys (6.89 +/- 4.14 years in all patients). In 14 (23%) cases, a positive family history was detected. The most frequent probable triggering factors were upper respiratory tract infections (14.8%) and positive throat culture for A group ss-hemolytic streptococcus (21.3%). Frequency of emotional stress and psychiatric morbidity were 54% and 9.8%, respectively. The most frequent localizations at onset were trunk (44.3%), extremities (54.0%), and scalp (36.0%). Three children (4.9%) had a history of dissemination from psoriatic diaper rash. In total, 51 (83.6%) patients presented with psoriasis vulgaris, eight (13.1%) with generalized pustular psoriasis, and the remaining two (3.3%) with erythrodermic psoriasis. CONCLUSION: The incidence of psoriasis among dermatological patients in childhood and adolescence was 3.8%. The disease tends to appear earlier in girls than boys. The authors suggested that stress and upper respiratory infections are the most important triggering factors in childhood and adolescence psoriasis.  相似文献   
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Although there are varied inheritance patterns in motor neuron disease (MND), the phenotype of MND is reported to be constant within these families, ie, cases of amyotrophic lateral sclerosis or primary lateral sclerosis do not occur in pedigrees with cases of spinal muscular atrophy. We describe four pedigrees whose members diverged in the phenotype of MND expressed. The intrafamilial variation of phenotype suggests a similar pathogenesis for some of the varied types of familial MND and the need for careful inquiry of family history in all patients with MND.  相似文献   
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Study on the pathogenicity of Campylobacter jejuni by modifying the medium   总被引:1,自引:0,他引:1  
Campylobacter jejuni has been documented as one of the major aetiological agents of diarrhoeal illness all over the world. Studies revealed its pathogenicity by different assay methods, but none could be strongly recommended as a tool for differentiating toxigenic strains of C. jejuni. This study was an attempt to demonstrate better its pathogenicity by media modification. Fifteen isolates of C. jejuni recovered from diarrhoeal patients at the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), Dhaka Hospital were included in this study. The standard medium for C. jejuni was modified by the incorporation of FeCl3 at different concentrations. The pathogenicity of the test isolates were studied by rabbit ileal loop assay; Chinese hamster ovary (CHO), human epithelial cervical carcinoma (HeLa); Y-1 adrenal cell lines and suckling mouse assay. Sonicated extracts of the test organisms, grown with FeCl3 supplement, were also assayed. An enhanced growth of C. jejuni was obtained with the increasing concentration of FeCl3 supplementation in the medium. Only five isolates of C. jejuni produced cytotoxic effect on HeLa cell monolayer. Other cell lines were not affected by the test specimens or sonicates. Rabbit ileal loop assay did not reveal any fluid accumulation but on dissection, the test loops were found highly haemorrhagic. No heat-stable (ST) toxin could be detected. Cell-free culture supernatant of patients' isolates of C. jejuni had an effect on HeLa cell monolayer. Sonicated extracts of patients' extracts had a greater effect on HeLa cell monolayer. Pathogenic strains of C. jejuni might be distinguished on HeLa cell monolayer using its sonicated extracts.  相似文献   
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