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31.
Carvacrol is a dietary polyphenol from Lamiaceae plants that has been shown to possess a wide range of biological activities including antioxidant and antitumor effects. This study aimed to investigate its anti-inflammatory and antioxidant effects on N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) induced gastric carcinogenesis in Wistar rats. Forty-nine rats were randomly assigned to four treatment and three control groups. Over 60 days, MNNG (200 mg/kg BW) was orally applied to animals of groups 1–5 while the rats in groups 2–5 also received different doses of carvacrol (10, 25, 50, and 100 mg/kg BW, respectively) until the end of the experiment. Group 6 rats were treated with 100 mg/kg BW carvacrol and no MNNG whereas group 7 was the control group without any treatment. After the euthanasia of all rats, the inflammatory cytokines and oxidative stress parameters were assessed in the blood and tissues. The expression of caspase 9, Bax, and Bcl-2 proteins in the stomach tissues were investigated through histopathological examinations. Statistically significant differences were observed in the body weight, oxidative stress, and inflammation parameters of groups 1 to 6 compared to group 7 (p ≤ 0.001). Animals in MNNG groups 2 and 3 treated with the low dose carvacrol (10 and 25 mg/kg BW) showed significantly reduced oxidative stress, inflammation, and apoptotic effect compared to animals of the MNNG groups receiving increased doses of carvacrol (50 and 100 mg/kg BW) or no carvacrol. Rats exposed to MNNG exhibited gastric cancer cells in several areas. In the MNNG group receiving 100 mg/kg BW carvacrol, the inflammatory cell infiltration was observed in gastric mucosal and submucosal areas whereas MNNG rats supplemented with 10 and 25 mg/kg BW carvacrol showed no pathological alterations of the gastric cells. The results of this study indicate that significant antioxidant and anti-inflammatory effects induced by carvacrol at doses of 10 and 25 mg/kg BW interfered with gastric carcinogenesis induced by MNNG in Wistar rats as well as provide hepatoprotection. However, high doses of carvacrol (50 and 100 mg/kg BW) increased oxidative stress, inflammation, and apoptosis.  相似文献   
32.
Inhibitor-of-apoptosis proteins (IAPs) mediate cancer cell survival and chemoresistance. We analyzed the expressions of X-linked IAP (XIAP), survivin, and livin in malignant mesothelioma. Ten effusions were analyzed for XIAP, survivin, and livin expression using immunoblotting. Based on the immunoblotting results, 112 mesotheliomas from 94 patients (pleural, n = 77; peritoneal, n = 35; solid, n = 68; effusions, n = 44) were immunostained for XIAP and survivin expression. Results were analyzed for associations with anatomic site (pleura versus peritoneum), specimen type (solid versus effusion), proliferation (Ki-67 score), and survival. Immunoblotting showed expression of XIAP in 9 of 10 effusions and that of survivin in 4 of 10 effusions, but no expression of livin. Immunohistochemistry showed cytoplasmic XIAP expression in 71 of the 112 (63%) tumors. XIAP expression was significantly higher in peritoneal mesotheliomas than in pleural mesotheliomas (P = .001) and in effusions than in solid lesions (P = .017). Cytoplasmic survivin was found in 75 of the 112 (67%) tumors and showed no site-related difference. Nuclear survivin was expressed in 37 of the 112 (33%) tumors, with a trend for positive association with the Ki-67 score (P = .051). Nuclear survivin (P = .003) and Ki-67 (P = .013) were downregulated in effusions as compared with solid tumors. Higher XIAP expression and Ki-67 score were associated with a trend for poor overall survival (P = .064 for both) in the univariate analysis. XIAP and survivin, but not livin, are frequently expressed in malignant mesotheliomas. Nuclear survivin expression is reduced in effusions as compared with solid lesions concomitantly with reduced proliferation. XIAP is upregulated in mesothelioma effusions and peritoneal mesotheliomas, suggesting a prosurvival role in malignant mesothelioma cells, particularly at these anatomic sites.  相似文献   
33.
Adherence of the opportunistic fungus Aspergillus fumigatus to the extracellular matrix components is considered a crucial step in the establishment of the infection. Given the high carbohydrate content of these glycoproteins and the role of carbohydrate-protein interactions in numerous adherence processes, the presence of a lectin in A. fumigatus was investigated. Different fungal extracts obtained by sonication or grinding in liquid nitrogen from resting or swollen conidia, as well as from germ tubes and mycelium, were tested by hemagglutination assays using rabbit erythrocytes. A lectin activity was recovered in all the extracts tested. However, sonication of resting conidia resulted in the highest specific activity. Purification of the lectin was achieved by gel filtration followed by ion-exchange and hydrophobic-interaction chromatographies. Analysis of the purified lectin by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed an apparent molecular mass of 32 kDa, which is similar to that of the alkaline protease already identified from different strains of A. fumigatus. However, as evidenced by the use of an alkaline protease-deficient mutant, the two activities were supported by distinct proteins. In addition, hemagglutination inhibition experiments using different saccharides and glycoproteins demonstrated the specificity of the lectin for sialic acid residues. Together these results suggest that this lectin may contribute to the attachment of conidia to the extracellular matrix components through the recognition of the numerous terminal sialic acid residues of their carbohydrate chains.  相似文献   
34.

Objective

To determine the extent to which physicians in different countries intend to inform terminal patients and relatives about prognosis, and to identify physician characteristics associated with an active approach to such discussions.

Methods

In the context of a European research project, a study on disclosing prognosis was conducted in seven countries. A written questionnaire with questions regarding hypothetical cases and actual practices was sent to physicians from specialties involved in the care of dying patients.

Results

10,139 questionnaires were studied. The response rate was greater than 50% in all countries except Italy (39%). The percentage of physicians who indicated that they would actively inform competent patients of their prognosis varied between countries from 52% in Italy to 99% in Sweden. For informing relatives of incompetent patients, rates were higher, ranging from 86% in Denmark to 98% in Australia. Younger physician age and training in palliative care were associated with an active intention to discuss prognosis.

Conclusion

Physicians’ intentions to discuss prognosis with patients and families vary largely across countries. Physician age and training in palliative care may also affect intentions.

Practice implications

Continuing training should focus on improving physicians’ ability to communicate responsibly about prognosis with patients and families.  相似文献   
35.
The drinking habits, demographic characteristics and knowledge about the effects of drinking during pregnancy of 380 pregnant women in Belfast were investigated. Forty-five per cent of the women were non-drinkers, 39% were occasional drinkers and 16% were regular drinkers. The majority of women knew that alcohol could harm their babies but were unsure of the specific effects. Regular drinkers were more likely than occasional drinkers or non-drinkers to say that harm would only be done if alcohol was taken in excess. The topic of alcohol is rarely discussed at antenatal clinics and cases of fetal alcohol syndrome, an uncommon but preventable condition, are probably being missed as a result. There is a need for more health education for the general public, especially school children, and for increased awareness among health professionals that the problem of alcohol in pregnancy exists and is likely to increase if the trend towards alcohol abuse among the younger members of the population continues.  相似文献   
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We report a female child with tetrasomy of the 15q11-q13 chromosomal region, and autistic disorder associated with mental retardation, developmental problems and behavioral disorders. Combining classical and molecular cytogenetic approaches by fluorescence in situ hybridization technique, the karyotype was demonstrated as 47,XX,+mar.ish der(15)(D15Z1++,D15S11++,GABRB3++,PML-). Duplication of the 15q proximal segment represents the most consistent chromosomal abnormality reported in association with autism. The contribution of the GABA receptor subunit genes, and other genes mapped to this region, to the clinical symptoms of the disease is discussed.  相似文献   
40.
Therapy of Sneddon syndrome   总被引:2,自引:0,他引:2  
We report the case of a young woman with progressive cognitive decline and epilepsy. She showed ischemic cerebrovascular disease and proximal livedo racemosa. Antiphospholipid antibody (aPL) could not be detected and there were no microemboli on continuous transcranial Doppler ultrasonography monitoring. Histology of cerebral vessels showed intimal hyperplasia in small leptomeningeal venous vessels and micronecrosis of grey and white matter. We subsequently made the diagnosis of aPL-negative Sneddon Syndrome (SNS). Anticoagulation with warfarin could not be initiated because of a drug-resistant epilepsy with the risk of falls and subsequent bleeding; immunosuppression with steroids and azathioprine was ineffective, as was initial antiplatelet therapy with clopidogrel alone. However, when we intensified antiplatelet therapy by combining clopidogrel and ASS, a slowing of disease progression, as assessed by neuropsychological testing and magnetic resonance imaging, was noted on a follow-up after 6 months. Therapeutic options in SNS in both aPL-positive and aPL-negative patients with SNS are discussed.  相似文献   
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