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A Vasconcelos

Publications and source records attributed to A Vasconcelos.

10 recordsLinked to original sources
PubMed2004

HER2 polymorphism and breast cancer risk in Portugal.

Breast cancer is a major public health problem around the world, and its carcinogenesis is not yet well understood. The human epidermal growth factor Receptor 2 (HER2) seems to play an important role in the development of this neoplasia, and genetic alterations in this gene, such as point mutations and polymorphisms have been detected in breast cancer patients. We analysed the frequency of a single nucleotide polymorphism in the HER2 gene in blood samples from 152 breast cancer patients and 146 healthy controls using the polymerase chain reaction methodology, followed by restriction fragment length polymorphism (PCR-RFLP). We found a twofold increase in risk of breast cancer in women who are carriers of a Val allele genotype-Ile/Val and Val/Val genotypes [odds ratio (OR)=2.00; 95% confidence interval (CI) 1.23-3.25; P=0.005]. Our results indicate an association between the presence of the Val allele in the HER2 polymorphism and the risk of breast cancer. Further studies are needed to evaluate the role of this polymorphism in the behaviour of breast cancer.

Breast Neoplasms↗
PubMed2003

Association between CYP2E1 polymorphisms and susceptibility to prostate cancer.

Several genetic alterations have been associated with sporadic prostate cancer (PCa). In this study, the association between RsaI and DraI polymorphisms of CYP2E1 and PCa risk was analysed in a case-control study of 227 individuals using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Regarding DraI polymorphisms, the DD genotype is over-represented in PCa cases when compared with the control group (odds ratio (OR) 2.12; 95% confidence interval (CI) 1.11-4.05; P=0.022). Regarding the RsaI polymorphism, no significant differences were found. The results of this study indicate that DraI polymorphisms of the CYP2E1 gene may be associated with a twofold increased risk for the development of PCa.

Adult↗
PubMed2002

Endothelial nitric oxide synthase gene polymorphisms and genetic susceptibility to prostate cancer.

The endothelial cell-specific form of nitric oxide synthases (ecNOS) is localized at 7q35-q36 and is involved in vascular development and tumour growth in human prostate cancer. We have conducted a case-control study to investigate the prevalence of two polymorphisms at intron 4 (ecNOS4a/b) and exon 7 (Glu-Asp298) of ecNOS gene in 125 prostate cancer (PCa) patients and in 153 controls. We observed that the a-allele (aa or ab genotypes from ecNOS4a/b) was over-presented in the group of PCa with Gleason histological grade >or=7 (P=0.041). With regard to the Glu-Asp298 polymorphism, patients with the T-allele were younger than patients with no T-allele (P=0.037), and a statistically significant difference was noted in the Glu-Asp298 genotype distribution between cases with advanced disease and cases with localized disease (P=0.0013). When comparing cases and controls with logistic regression analysis we observed that the presence of the a-allele is associated with prostate cancer risk (odds ratio (OR) 1.83; 95% confidence interval (CI) 1.06-3.17; P=0.029), to high histological grade (Gleason >or=7) of PCa (OR 2.18; 95% CI 0.95-4.98; P=0.062) and with the risk of progression of the cancer disease (OR 2.85; 95% CI 1.19-6.82; P=0.018). Furthermore, we found that carriers with the combination of the a-allele (aa and ab ecNOS4a/b genotypes) and T-allele (GT and TT from Glu-Asp298) have a threefold increase in prostate cancer risk (OR 3.13; 95% CI 1.41-6.91, P=0.004). In summary, we have identified an NO-related genetic risk factor for prostate cancer that may help in understanding the molecular mechanism involved in the individual susceptibility to prostate cancer.

Adult↗
PubMed2000

Cimetidine (Tagamet) is a reproductive toxicant in male rats affecting peritubular cells.

Cimetidine (Tagamet) is a potent histaminic H2-receptor antagonist, extensively prescribed for ulcers and now available without prescription. Cimetidine is a known testicular toxicant, but its mechanism of action remains uncertain. Rats were treated i.p. with cimetidine either at 50 mg/kg or 250 mg/kg body weight for 59 days. Accessory sex organ weights, but not testis weight, were significantly reduced in the high dose treated groups. FSH levels were significantly elevated in both treated groups, but testosterone levels were unchanged. A high degree of variability characterized testis histology, with most tubules appearing normal and some tubules (15-17%) partially lacking or devoid of germ cells. Morphometry showed that although seminiferous tubule volume was not significantly changed, the volume of peritubular tissue was reduced in the high dose group. There was extensive duplication of the basal lamina, lamina densa in both apparently normal spermatogenic tubules and severely damaged tubules. Apoptotic peritubular myoid cells were also found. TUNEL labeling confirmed extensive apoptotic cell death in peritubular cells, but revealed apoptosis of vascular smooth muscle. Given that 1) peritubular myoid cell apoptosis occurs in apparently normal tubules, that 2) basal lamina disorders are found, and that 3) peritubular cells are lost from the testis, it is suggested that the primary event in cimetidine-related damage is targeted to testicular smooth muscle cells. This is the first in vivo-administered toxicant to be described that targets myoid cells, resulting in abnormal spermatogenesis.

Animals↗
PubMed1997

[The effects of a cardiac rehabilitation program on 2 populations of coronary patients: acute myocardial infarct and coronary bypass surgery].

UNLABELLED: Cardiac rehabilitation programmes (CRP) have proven beneficial in coronary heart disease. The purpose of this study was to evaluate the effects of our CRP on two coronary heart disease populations: after acute myocardial infarction (AMI-CRP) and after coronary artery bypass surgery (CABG-CRP). Results were compared to control groups (AMI-C and CABG-C). POPULATION: Group AMI-CRP: n = 43 patients, mean age = 48.7 +/- 9.8 years; Group AMI-C: n = 20 patients, mean age = 59.2 +/- 11.5 years; Group CABG-CRP: n = 54 patients, mean age = 54.9 +/- 9.7 years; Group CABG-C: n = 20 patients, mean age = 56.5 +/- 9.9 years. All patients are male and there were no significant differences in ventricular function and coronary disease severity. Parameters were evaluated in the AMI groups at discharge, 3 and 12 months after acute episode; in the CABG groups 3 and 12 months after surgery. RESULTS: Both CRP groups improved their exercise capacity (significantly improved the peak values of METs and double product). A favorable lipid profile change (total cholesterol and HDL) was induced in the CABG-CRP group and more significant in the AMI-CRP group. No significant differences were observed in obesity indexes (body weight and BMI > or = 27.8 Kg/m2). A increase in nonsmokers was important in all groups. Professional reintegration was 91.7% in the AMI-CRP group and 84.4% in the CABG-CRP group. The CRP groups showed a better knowledge of the disease, and a beneficial change in relation to themselves and the world that resulted in a decrease in depression and anxiety. CONCLUSIONS: Participation in our cardiac rehabilitation program, either after AMI or after CABG, improves cardio-respiratory fitness, favorably influences blood lipid profiles, and improves self-reliance and quality of life.

Adult↗
PubMed1984

[Keratoacanthoma centrifugum marginatum].

The authors describe an observation of multiple keratoacanthomas appearing within 3 years, mainly located on the right forearm. Clear confluence and centrifugal extension, due to progressive appearance of surrounding lesions forming a 12 X 10 cm. ulcerated surface characterized this case. The topical application of 5-FU was effective, nevertheless further surrounding lesions have made their appearance. The clinico-pathological features and evolution are those of keratoacanthoma centrifugum marginatum , a rare type of multiple and localized keratoacanthoma.

Aged↗
PubMed1984

Phenotype study of fresh and cultured hairy cells with the use of immunologic markers and electron microscopy.

The phenotype of fresh and cultured leukemic cells from patients with hairy cell leukemia was studied using a panel of monoclonal antibodies in addition to the detection of peroxidase activity under electron microscopy. In fresh samples, the leukemic cells from 11 patients displayed predominantly a B phenotype, as judged by their reactivity with the B1 monoclonal antibody and surface immunoglobulin expression. Ultrastructural peroxidase activity, characteristic of hairy cells, was observed in all cases studied. When hairy cells were cultured in the presence of phytohemagglutinin and irradiated T cells, their phenotype converted from surface Ig+, B1+, OKT3-, OKT11- to surface Ig-, B1+, OKT3-, OKT11+. In contrast, the peroxidase activity remained unchanged. Some hairy cells were also OKM1+, but no conclusion could be made about the MO2 antigen, a more specific marker of monocytes. The variability of the phenotype in vivo and in vitro indicates that reliable markers are required for identifying hairy cells. When studied together, the staining by B1 monoclonal antibody and the ultrastructural detection of peroxidase, enable the identification of hairy cells with certainty.

Antibodies, Monoclonal↗
PubMed1971

Isolation of Intact Chloroplasts from Euglena gracilis by Zonal Centrifugation.

Chloroplasts were separated from Euglena gracilis by zonal centrifugation at low speed in density gradients of Ficoll or dextran. The chloroplasts were intact by the criteria of ultrastructure and their content of ribulose diphosphate carboxylase and soluble protein. The chloroplasts also contained ribosomes and ribosomal RNA uncontaminated by the corresponding cytoplasmic particles.

Journal Article↗