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91.
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Previously, we have shown that highly specific antibodies against cytochrome P450 enzymes can be produced by targeting a 5-amino acid sequence at the C-terminus. Although rat CYP3A1 and CYP3A2 share 89% amino acid sequence similarity, they differ by 3 out of 5 of their C-terminal residues. In an effort to produce antibodies specific to each form, rabbits were immunised with the peptides IITGS and VINGA, corresponding to the C-termini of CYP3A1 and CYP3A2, respectively. Both antibodies bound strongly to hepatic microsomal fraction from rats treated with pregnenolone 16α-carbonitrile (PCN) in enzyme-linked immunosorbent assay. Binding of the anti-IITGS antibody was strongly inhibited by incubation with IITGS, but VINGA was 60 times less effective. Conversely, binding of the anti-VINGA antibody was inhibited by VINGA 100 times more effectively than IITGS. Similar inhibition of antibody binding was also found using immunoblotting. Immujnoadsorption using the anti-IITGS antibody yielded a single protein from solubilised hepatic microsomal fraction from PCN-treated rats, which was recognised only by the anti-IITGS antibody. Both antibodies bound to single proteins in the liver which were increased following treatment with PCN, but only the anti-IITGS antibody recognised protein in the lung, small intestine, and kidney of untreated and PCN-treated rats. Also, the binding of the two antibodies to hepatic and extrahepatic microsomal fractions from uninduced and induced rats showed differences in the expression of proteins recognised by the two antibodies, providing further evidence of antibody specificity. Thus, the binding of anti-IITGS and anti-VINGA antibodies is mutually exclusive and consistent with specific binding to their target antigens, CYP3A1 and CYP3A2, respectively. Immunocytochemistry was used to determine the distribution of CYP3A1 and CYP3A2. In the liver of untreated animals, both CYP3A1 and CYP3A2 were found to be expressed in the centrilobular region. However, some CYP3A1 immunoreactivity was also detected in many, but not all, hepatocytes throughout the lobule. However, following treatment of rats with PCN, both CYP3A1 and CYP3A2 were found to be strongly expressed in hepatocytes throughout the lobule, although CYP3A2 showed greater expression in the centrilobular region. PCN treatment was also found to result in induction of CYP3A1 in specific regions of the small intestine, lung, and kidney.  相似文献   
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Our study on long-term outcome of presymptomatic testing for Huntington disease had two aims: the comparison of the psychological well-being and social adjustment of carriers and non-carriers of the mutation, and the identification of psychological determinants to improve care/support of testees. We performed a cross-sectional study of 351 persons who underwent presymptomatic testing. Those who had motor signs were excluded from the comparison of asymptomatic carrier and non-carriers. A structured interview including five self-report scales and the MINI (Mini International Neuropsychiatric Inventory) was proposed to detect a psychopathology or problem with social adjustment.We interviewed 119 testees (53%), 62 non-carriers and 57 carriers after a mean delay of 3.7 years (range: 0.32 to 8.9) after their result. Depression was frequent in asymptomatic carriers (58%). Interestingly, the self reported impact of the test showed that 27% of non-carriers did not cope well with a favourable result, and a significant percentage of non-carriers (24%) were depressed during follow-up. Multivariate analysis showed that only a previous episode of depression was predictive of depression after genetic testing in both carriers and non-carriers of the HD mutation (P<0.0001).Psychological support is necessary for all testees regardless of the result of their presymptomatic test, because psychiatric care is often needed by both carriers and non-carriers.  相似文献   
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The Xeroderma pigmentosum complementation group D (XPD) is a critical protein in the nucleotide excision repair system for DNA damage. Genetic variations in XPD exert an important effect on the capacity of DNA repair. In this study, we examined Lys751Gln polymorphism at the XPD gene in 244 melanoma patients and 251 healthy individuals (as controls) from the south-eastern region of Sweden. The associations of polymorphism with melanoma risk, as well as with melanoma features and pigment phenotypes of the melanoma patients were analysed. DNA was extracted from the mononuclear cells of venous blood of the melanoma patients and controls. XPD codon 751 was genotyped by the PCR restriction fragment length polymorphism technique. Results showed that there was no difference in the distribution of the XPD codon 751 genotypes between the melanoma patients and healthy controls. However, the Gln/Gln genotype was found to be associated with melanoma risk in the male population. Furthermore, the frequency of the Gln/Gln genotype was significantly higher in the early stages of melanomas, whereas Lys/Gln was more frequent in the later stages and in the patients with melanoma located on intermittently UV-exposed areas. No correlations between the polymorphisms and phenotypes of the patients were found. In conclusion, Gln/Gln was a useful genetic marker for melanoma risk in the males, while Lys/Gln was an important predictor for melanoma progression.  相似文献   
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Ethnic differences of breast cancer genomics have prompted us to investigate the spectra of BRCA1 and BRCA2 mutations in different populations. The prevalence and effect of BRCA 1 and BRCA 2 mutations in Middle Eastern population is not fully explored. To characterize the prevalence of BRCA mutations in Middle Eastern breast cancer patients, BRCA mutation screening was performed in 818 unselected breast cancer patients using Capture and/or Sanger sequencing. 19 short tandem repeat (STR) markers were used for founder mutation analysis. In our study, nine different types of deleterious mutation were identified in 28 (3.4%) cases, 25 (89.3%) cases in BRCA 1 and 3 (10.7%) cases in BRCA 2. Seven recurrent mutations identified accounted for 92.9% (26/28) of all the mutant cases. Haplotype analysis was performed to confirm c.1140 dupG and c.4136_4137delCT mutations as novel putative founder mutation, accounting for 46.4% (13/28) of all BRCA mutant cases and 1.6% (13/818) of all the breast cancer cases, respectively. Moreover, BRCA 1 mutation was significantly associated with BRCA 1 protein expression loss (p = 0.0005). Our finding revealed that a substantial number of BRCA mutations were identified in clinically high risk breast cancer from Middle East region. Identification of the mutation spectrum, prevalence and founder effect in Middle Eastern population facilitates genetic counseling, risk assessment and development of cost‐effective screening strategy.  相似文献   
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The fabrication of bimetallic nanoparticles (BNPs) using plant extracts is applauded since it is an environmentally and biologically safe method. In this research, Manilkara zapota leaf extract was utilized to bioreduce metal ions for the production of therapeutically important core–shell Au–Ag and hybrid (Au–ZnO and Ag–ZnO) BNPs. The phytochemical profiling of the leaf extract in terms of total phenolic and flavonoid content is attributed to its high free radical scavenging activity. FTIR data also supported the involvement of these phytochemicals (polyphenols, flavonoids, aromatic compounds and alkynes) in the synthesis of BNPs. Whereas, TEM and XRD showed the formation of small sized (16.57 nm) spherical shaped core–shell Au–Ag BNPs and ZnO nano-needles with spherical AuNPs (48.32 nm) and ZnO nano-rods with spherical AgNP (19.64 nm) hybrid BNPs. The biological activities of BNPs reinforced the fact that they show enhanced therapeutic efficacy as compared to their monometallic components. All BNPs showed comparable antibacterial activities as compared to standard tetracycline discs. While small sized Au–Ag BNPs were most effective in killing human hepato-cellular carcinoma cells (HepG2) in terms of lowest cell viability, highest intracellular ROS/RNS production, loss of mitochondrial membrane potential, induction of caspase-3 gene expression and enhanced caspase-3/7 activity. BNPs also effectively inhibited advanced glycation end products and carbohydrate digesting enzymes which can be used as a nano-medicine for aging and diabetes. The most important finding was the permissible biocompatibility of these BNPs towards brine shrimp larvae and human RBCs, which suggests their environmental and biological safety. This research study gives us insight into the promise of using a green route to synthesize commercially important BNPs with enhanced therapeutic efficacy as compared to conventional treatment options.

Graphical demonstartion of the Manikara zapota-mediated biosynthesis of Bimetallic nanoparticles (BNPs) and evalution of their biological activities.  相似文献   
99.
Lung hernias are rare. They are defined by the protrusion of lung parenchyma through a defect in the chest wall. A distinction is classically made between supraclavicular, thoracic or diaphragmatic hernias and congenital or acquired hernias. The latter can be classified by etiology as post-traumatic, postoperative, or pathological but can be spontaneous (even rarer) caused mainly by coughing efforts. The diagnosis is guided by the clinical presentation and confirmed by radiographic analysis, especially CT scan. The management, by conservative or surgical approach, depends on the clinical condition of the patient, the characteristics of the hernia and the existence or not of complications. We report the case of a 58-year-old patient, chronic smoker with no history of trauma, who presented with a chronic cough not improved by symptomatic treatment and in whom the clinical examination was without particularities. Chest CT scan showed discrete pulmonary emphysema with an intercostal pulmonary herniation at the level of the right fifth intercostal space associated with a bony outgrowth at the level of the middle arch of the right fifth rib. The pulmonary protrusion occurred through a parietal defect between the fifth rib and the bony protrusion. The management consisted of conservative treatment of the hernia with close clinical and radiological follow-up and medical treatment of the pulmonary emphysema and chronic cough associated with smoking cessation and hygienic and dietary rules.  相似文献   
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