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51.
BACKGROUND/AIMS: To report the generation of a new mouse model for a genetically determined corneal abnormality that occurred in transgenesis experiments. METHODS: Transgenic mice expressing mutant forms of Rab27a, a GTPase that has been implicated in the pathogenesis of choroideremia, were generated. RESULTS: Only one transgenic line (T27aT15) exhibited an unexpected eye phenotype. T27aT15 mice developed corneal opacities, usually unilateral, and cataracts, resulting in some cases in phthisical eyes. Histologically, the corneal stroma was thickened and vacuolated, and both epithelium and endothelium were thinned. The posterior segment of the eye was also affected with abnormal pigmentation, vessel narrowing, and abnormal leakage of dye upon angiography but was histologically normal. CONCLUSION: Eye abnormality in T27aT15 mice results from random insertional mutagenesis of the transgene as it was only observed in one line. The corneal lesion observed in T27aT15 mice most closely resembles posterior polymorphous corneal dystrophy and might result from the disruption of the equivalent mouse locus.  相似文献   
52.
Hemophilia is an important hemorrhagic disease in Brazil, affecting about 1 out of every 10,000 males. Patient's self-perception of hemophilia and interaction with the community are relevant to the clinical management of this disease. We investigated several social, psychological, and community aspects of hemophilia in a Brazilian population (Campinas, S?o Paulo State), interviewing 30 hemophiliac males, a control sample comprised of 73 non-hemophiliac brothers, and 641 individuals from the community. According to our results, more severe social disability in the hemophiliac patient was related to economic factors, mainly unemployment; however, no difference was found in relation to marital status, reproduction, or education. Self-perception of changes in health and lifestyle by individuals with hemophilia showed frequent self-stigmatization, along with depression, anxiety, and insecurity. The community showed a widespread lack of familiarity with hemophilia (49%), viewing people with hemophilia with the kinds of prejudices often observed in relation to people with infectious diseases, like AIDS. The paper concludes by recommending that a community-based program be implemented to improve the social adjustment status of individuals with hemophilia.  相似文献   
53.
The study investigates the need for instruction and support among wives of patients with myocardial infarction, applying the 'stress' theory. The data were gathered by questionnaires completed by 59 wives of patients with myocardial infarction. Feelings and symptoms indicative of stress did occur among wives of the patients. They assessed instruction especially concerning home care, as being inadequate. They stated that the support they received had come largely from their own relatives; more than one third of the respondents said they had received support from a nurse; one fifth said they had not received it from anyone. The 'instruction' model for wives and other relatives of patients with myocardial infarction, introduced at the end of the article, emphasizes the importance of relevant information and support to the close relatives of patients with myocardial infarction.  相似文献   
54.
Purpose Eggs are a food item of high nutritional value, a source of vitamin A and readily accessible to the general population.

Methods This paper analysed the effect of cooking on the retinol levels of free-range and caged hen eggs, using high performance liquid chromatography (HPLC). The retinol levels of hen and quail eggs were also compared.

Results The raw egg yolk retinol concentrations of free-range and caged hen eggs were 476.53±39.44 and 474.93±41.10 µg/100 g and cooked egg yolk concentrations were 393.53±24.74 and 379.01±30.78 µg/100 g, respectively; quail egg concentration was 636.56±32.71 µg retinol/100 g. No significant difference was found between the retinol of free-range and caged hen egg yolks; however, cooking diminished retinol levels, causing a loss of 17 and 20% in the free-range and caged hen egg yolks, respectively. Quail egg retinol concentration was significantly higher than that of the hens.

Conclusion The retinol found in 100 g of hen and quail egg yolks could supply around 42 and 70.7% of the vitamin A requirements of an adult man, and is accordingly considered an excellent source of this vitamin.  相似文献   
55.
This paper reports on a study of the G-6-PD deficiency in Bragan?a Paulista, S?o Paulo State, Brazil. A total of 4,621 male blood donors were investigated over a 36-month period. Of these, 80 had the G-6-PD deficiency. Molecular analysis was performed on 70 unrelated G-6-PD deficients through DNA amplification followed by digestion with restriction enzymes and single strand conformation polymorphism analysis (SSCP). In 98.6%, the G-6-PD A- (202 G<--A) mutation was observed through digestion of exon 4 with Nla III. The presence of an uncommon mutation in exon 9 was also observed through SSCP. No case of the Mediterranean variant was observed. These results indicate that the A- (202G<--A) variant, almost exclusive, was introduced into the community not only by individuals of African origin, but also by European immigrants, mainly Italian, Spanish, and Portuguese. The Italian contribution in terms of the G-6-PD Mediterranean variant was smaller than its contribution to beta thalassemia, probably due to the Northern Italian origin of these immigrants.  相似文献   
56.
The modulation played by reactive oxygen species on the angiotensin II-induced contraction in type I-diabetic rat carotid was investigated. Concentration-response curves for angiotensin II were obtained in endothelium-intact or endothelium-denuded carotid from control or streptozotocin-induced diabetic rats, pre-treated with tiron (superoxide scavenger), PEG-catalase (hydrogen peroxide scavenger), dimethylthiourea (hydroxyl scavenger), apocynin [NAD(P)H oxidase inhibitor], SC560 (cyclooxygenase-1 inhibitor), SC236 (cyclooxygenase-2 inhibitor) or Y-27632 (Rho-kinase inhibitor). Reactive oxygen species were measured by flow cytometry in dihydroethidium (DHE)-loaded endothelial cells. Cyclooxygenase and AT(1)-receptor expression was assessed by immunohistochemistry. Diabetes increased the angiotensin II-induced contraction but reduced the agonist potency in rat carotid. Endothelium removal, tiron or apocynin restored the angiotensin II-induced contraction in diabetic rat carotid to control levels. PEG-catalase, DMTU or SC560 reduced the angiotensin II-induced contraction in diabetic rat carotid at the same extent. SC236 restored the angiotensin II potency in diabetic rat carotid. Y-27632 reduced the angiotensin II-induced contraction in endothelium-intact or -denuded diabetic rat carotid. Diabetes increased the DHE-fluorescence of carotid endothelial cells. Apocynin reduced the DHE-fluorescence of endothelial cells from diabetic rat carotid to control levels. Diabetes increased the muscular cyclooxygenase-2 expression but reduced the muscular AT(1)-receptor expression in rat carotid. In summary, hydroxyl radical, hydrogen peroxide and superoxide anion-derived from endothelial NAD(P)H oxidase mediate the hyperreactivity to angiotensin II in type I-diabetic rat carotid, involving the participation of cyclooxygenase-1 and Rho-kinase. Moreover, increased muscular cyclooxygenase-2 expression in type I-diabetic rat carotid seems to be related to the local reduced AT(1)-receptor expression and the reduced angiotensin II potency.  相似文献   
57.
This cross-sectional study with university students examined the prevalence of regular consumption of fruits and vegetables and associated factors among students at a Federal university in Rio Branco, Acre State, Brazil. 863 undergraduates were interviewed in 2010. Overall prevalence of regular consumption of fruits and vegetables was 14.8%. Factors associated with regular consumption of fruits and vegetables were: socioeconomic classes A and B (PR = 1.70; 95%CI: 1.10-2.62), living with a partner (PR = 1.53; 95%CI: 1.02-2.29), regular physical activity (PR = 1.69; 95%CI: 1.11-2.56), and consumption of fast food twice a week or less (PR = 1.49; 95%CI: 1.04-2.13). A minority of the students met the recommendation to consume fruits and vegetables 5 or more days a week. Regular fruit and vegetable consumption was associated with socioeconomic status and healthy habits such as physical exercise and low consumption of fast food.  相似文献   
58.
Immune cells of myeloid origin, including microglia, macrophages, and myeloid-derived suppressor cells adopt immunosuppressive phenotypes that support gliomagenesis. Here, we tested an a priori hypothesis that single nucleotide polymorphisms (SNPs) in genes related to glioma-associated myeloid cell regulation and function are also associated with patient survival after glioma diagnosis. Subjects for this study were 992 glioma patients treated at The University of Texas MD Anderson Cancer Center in Houston, Texas between 1992 and 2008. Haplotype-tagging SNPs in 91 myeloid-associated genes were analyzed for association with survival by Cox regression. Individual SNP- and gene-based tests were performed separately in glioblastoma (WHO grade IV, n?=?511) and lower-grade glioma (WHO grade II–III, n?=?481) groups. After adjustment for multiple testing, no myeloid-associated gene variants were significantly associated with survival in glioblastoma. Two SNPs, rs147960238 in CD163 (p?=?2.2?×?10?5) and rs17138945 in MET (p?=?5.6?×?10?5) were significantly associated with survival of patients with lower-grade glioma. However, these associations were not confirmed in an independent analysis of 563 lower-grade glioma cases from the University of California at San Francisco Adult Glioma Study (p?=?0.65 and p?=?0.41, respectively). The results of this study do not support a role for inherited polymorphisms in myeloid-associated genes in affecting survival of patients diagnosed with glioblastoma or lower-grade glioma.  相似文献   
59.

Purpose

BRCA1 germline mutation is closely associated with triple-negative breast cancer. BRCA deficiency leads to impaired DNA repair and tumor development, and understanding this deficiency, in both hereditary and sporadic scenarios, is of great clinical and biological interest. Here, we investigated germline or somatic events that might lead to BRCA1 impairment in triple-negative breast cancer. We also analyzed the clinical implications associated with BRCA deficiency.

Methods

Next-generation sequencing for the BRCA1/2 genes and multiplex ligation-dependent probe amplification (MLPA) for the BRCA1 gene were performed for mutation screening. A customized bisulfite next-generation sequencing approach was used for assessing BRCA1 promoter methylation status in tumor tissue.

Results

A total of 131 triple-negative cases were assessed, and germline pathogenic variants were detected in 13.0% of all cases and in 26% of cases diagnosed in young women. Most germline pathogenic variants (88.2%) occurred in the BRCA1 gene. BRCA1 promoter hypermethylation was detected in 20.6% of tumors; none of these tumors were in BRCA1/2 pathogenic variant carriers. BRCA1 impairment by either germline or somatic events was significantly more frequent in young women (55% in those ≤ 40 years; 33% in those 41–50 years; 22% in those > 50 years of age) and associated with better overall and disease-free survival rates in this group of patients.

Conclusions

BRCA1 deficiency was recurrent in early-onset triple-negative breast cancer in Brazilian patients and associated with improved survival. With the new treatment modalities being investigated, including poly (ADP-ribose)-polymerase (PARP) inhibitor therapy, our results suggest that a significant proportion of young women with this subtype of tumor might benefit from PARP inhibitor treatment, which warrants further investigation.
  相似文献   
60.
The present study was designed to examine the effects of endosulfan, decis, baytroid, and sevin on the learning ability of Africanized honey bees (Apis mellifera L.). Although these insecticides were recommended by the government of Brazil to control the cotton boll weevil, the effects on bees have been unknown. Results of the present research show that: (1) bees readily consume each of the pesticides when placed in a sucrose solution; (2) the odors of the pesticides are not repellent to bees, and such odors can serve as conditioned stimuli; (3) learning occurs to various degrees when the insecticides are combined with the sucrose solution and used as an unconditioned stimulus; and (4) feeding the insecticides to the bees 1 h prior to conditioning leads to differing mortality. Because of the importance of bees for honey production, as well as pollination of cotton and other crops, recommendations are made for the use of decis and other measures for boll weevil control. Received: 20 August 1998/Accepted: 22 May 1999  相似文献   
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