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981.
Colorectal cancer is one of the most common malignancies in the Western world and is an example of a solid tumour in which hypoxia is a common feature and develops because of the inability of the vascular system to supply adequate amounts of oxygen to growing tumours. Hypoxia effects on tumour cell biology can be detected and characterized using different methods. The use of imaging with γ-emitting radionuclides to detect hypoxic tissue was first suggested by Chapman in 1979 [N Engl J Med 301 (1979) 1429–1432]. 99mTc-4,9-diaza-3,3,10,10-tetramethyldodecan-2,11-dione dioxime, also known as 99mTc-HL-91, has been among the most studied hypoxia markers.The objective of this study was to correlate the uptake of 99mTc-HL-91 and 99mTc-MIBI in colon cancer cells under normoxic and hypoxic conditions and to compare this information with some parameters such as oxidative stress and mitochondrial dysfunction of the cells analyzed by flow cytometry.Our results show that the in vitro 99mTc-HL-91 uptake is higher in hypoxic conditions, which is confirmed by the decreased uptake of 99mTc-MIBI. Flow cytometry results demonstrate that hypoxic conditions used are not enough to induce cellular death, but are responsible for the alterations in the intracellular redox environment, namely, increase of ROS production, proteic pimonidazol-derived adduct formation and alteration in the mitochondrial membrane permeability. Therefore, these results confirm that 99mTc-HL-91 is a radiopharmaceutical with favourable characteristics for detecting hypoxia.  相似文献   
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Neospora caninum is a tissue-cyst forming parasite that has been recognized worldwide as a cause of abortion in cattle. Despite the ubiquitous distribution of this parasite and its broad range of hosts, the number of N. caninum isolates obtained to date is limited. In addition, the majority of isolates have been obtained from clinically affected hosts, therefore potentially biasing this population towards more virulent isolates. This report describes the isolation and biological characterisation of a new N. caninum isolate, Nc-Goiás 1, obtained from an asymptomatic, naturally infected calf from Brazil. This new isolate was identified as a member of the N. caninum species by polymerase chain reaction (PCR) using specific primers based on the N. caninum internal transcribed spacer 1 (ITS-1) sequence, and was genetically identified at multiple loci using microsatellite analysis. Finally, a pathogenicity study was conducted in a BALB/c mice model. All Nc-Goiás 1-infected mice survived without exhibiting any clinical signs. Further pathogenic characterisation of this isolate suggested that Nc-Goiás 1 is less virulent than other N. caninum isolates (Nc-Liv and Nc-1) studied in this mouse model. This is the first report of the isolation and biological characterisation of N. caninum from an infected but clinically healthy calf in South America.  相似文献   
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The most common apolipoprotein E (APOE) allelic variation is implicated in many age-related diseases and human longevity with controversial findings. We investigated the effect of APOE gene polymorphism on all-cause mortality in elderly patients taking into consideration the functional disability, cognitive impairment, malnutrition, and the occurrence of common age-related diseases. APOE genotypes were determined in 2,124 geriatric hospitalized patients (46.5% men and 53.5% women; mean age, 78.2 ± 7.1 years; range, 65–100 years). At hospital admission, all patients underwent a comprehensive geriatric assessment to evaluate functional disability, cognitive status, nutritional status, and comorbidity. The main and secondary diagnoses at hospital discharge were also recorded. Mortality status was evaluated in all patients after a maximum follow-up of 5 years (range, from 1.26 to 5.23 years; median, 2.86 years). During the study period, 671 patients died (32.0%). At hospital admission, these patients showed a significant higher prevalence of cardiovascular diseases (56.3% vs 53.4%; p = 0.007), neoplasias (32.3% vs 13.7%; p < 0.001), and lower prevalence of neurodegenerative diseases (17.7% vs 20.7%; p < 0.001) than survived patients. Moreover, they also showed an higher prevalence of disability (52.0% vs 25.6%; p < 0.001), cognitive impairment (31.0% vs 18.8%; p < 0.001), and malnutrition (74.0% vs 46.1%; p < 0.001) than survived patients. In the overall study population, the APOE ε2 allele was significantly associated to neurodegenerative diseases (odds ratio = 0.59; 95% confidence interval (CI), 0.37–0.94). No significant association between the APOE polymorphism and disability, malnutrition, co-morbidity status, and with all-cause mortality was observed. In patients with cardiovascular diseases, however, a decreased risk of all-cause mortality was found in the ε2 allele carriers (hazard ratio = 0.56; 95% CI, 0.36–0.88). In this population, APOE allele variants might play a role on cardiovascular disease-related mortality.  相似文献   
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This participatory research aimed to evaluate behavioral changes in fifteen parents of pre-school children to prevent the risk factors of arterial hypertension, by applying education technology for health that is based on the Health Beliefs Model at a private school in Fortaleza, State of Ceará, Brazil. The field research was carried out through educational workshops and data collection through questionnaires and interviews. After organizing the data into categories, analysis was based on the premises of health education. Through the application of education technology for health, significant changes were observed in the parents' habits, besides the roles they assumed as agents of change and multipliers of educational actions in the family. Although difficulties arose in the process of change, the parents were motivated to prevent the risk factors of arterial hypertension in themselves and their children. Thus, education technology for health based on the Health Beliefs Model proved to be efficient, as significant behavioral changes occurred and the parents were motivated to prevent arterial hypertension by means of a healthy lifestyle.  相似文献   
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