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O Oduwole

Publications and source records attributed to O Oduwole.

10 recordsLinked to original sources
PubMed2004

17 beta-hydroxysteroid dehydrogenases--their role in pathophysiology.

17 beta-Hydroxysteroid dehydrogenases (17HSDs) regulate the biological activity of sex steroid hormones in a variety of tissues by catalyzing the interconversions between highly active steroid hormones, e.g. estradiol and testosterone, and corresponding less active hormones, estrone and androstenedione. Epidemiological and endocrine evidence indicates that estrogens play a role in the etiology of breast cancer, while androgens are involved in mechanisms controlling the growth of normal and malignant prostatic cells. Using LNCaP prostate cancer cell lines, we have developed a cell model to study the progression of prostate cancer. In the model LNCaP cells are transformed in culture condition into more aggressive cells. Our data suggest that substantial changes in androgen and estrogen metabolism occur in the cells, leading to increased production of active estrogens during the process. In breast cancer, the reductive 17HSD type 1 activity is predominant in malignant cells, while the oxidative 17HSD type 2 mainly seems to be present in non-malignant breast epithelial cells. Deprivation of an estrogen response by using specific 17HSD type 1 inhibitors is a tempting approach in treating estrogen-dependent breast cancer. Our recent studies demonstrate that in addition to sex hormone target tissues, estrogens may be important in the development of cancer in some other tissues previously not considered to be estrogen target tissues, such as the gastrointestinal tract.

17-Hydroxysteroid Dehydrogenases↗
PubMed2002

17 beta-hydroxysteroid dehydrogenases and cancers.

17 beta-Hydroxysteroid dehydrogenases (17HSDs) catalyze the interconversions between active 17 beta-hydroxysteroids and less-active 17-ketosteroids thereby affecting the availability of biologically active estrogens and androgens in a variety of tissues. The enzymes have different enzymatic properties and characteristic cell-specific expression patterns, suggesting differential physiological functions for the enzymes. Epidemiological and endocrine evidence indicate that estrogens play a key role in the etiology of breast cancer while androgens are involved in mechanisms controlling the growth of prostatic cells, both normal and malignant. Recently, we have developed, using LNCaP prostate cancer cell lines, a cell model to study the progression of prostate cancer. In the model LNCaP cells are transformed in culture condition to more aggressive cells, able to grow in suspension cultures. Our results suggest that substantial changes in androgen and estrogen metabolism occur in the cells during the process. These changes lead to increased production of active estrogens during transformation of the cells. Data from studies of breast cell lines and tissues suggest that the oxidative 17HSD type 2 may predominate in human non-malignant breast epithelial cells, while the reductive 17HSD type 1 activity prevails in malignant cells. Deprivation of an estrogen response by using specific 17HSD type 1 inhibitors is a tempting approach to treat estrogen-dependent breast cancer. Our recent studies demonstrate that in addition to sex hormone target tissues, estrogens may be important in the development of cancer in some other tissues previously not considered as estrogen target tissues such as colon. Our data show that the abundant expression of 17HSD type 2 present in normal colonic mucosa is significantly decreased during colon cancer development.

17-Hydroxysteroid Dehydrogenases↗
PubMed1983

Ventilatory capacity in Nigerian school children.

Forced expiratory volume in one second (FEV1.0) and forced vital capacity (FVC) were determined in 1001 healthy Nigerian school children, aged between four and 16 years. The results were analysed with respect to the ages, heights, weights and body surface areas of the subjects. Among the variables used, weight showed the best correlation with FEV1.0 in both sexes and with FVC in males. Conversely, height showed the best correlation with FVC in females. However, the differences between these correlations were not significant. The median values obtained were lower than those reported in caucasian children at all height levels, but similar to the only available data in the literature for African children. Median FEV1.0 and FVC values were higher in males than in females at most ages, particularly the younger ones. Formulae for the medians and corresponding 2.5 and 97.5% points have been produced, using either height or weight as independent variable.

Adolescent↗
PubMed1982

Ascaris and bronchial asthma in children.

Skin tests with the Ascaris antigen were carried out in 270 children with bronchial asthma and 220 controls. Faecal and sputum specimens were also examined for helminths. Twenty-seven per cent of the asthmatic children had positive reactions to the Ascaris antigen compared with 8% of controls (P less than 0.001). The positive reactions were, however, not related to the sex of the patients, severity of asthma, the presence of Ascaris ova in the faeces or the blood eosinophil counts. Larvae of helminths were not found in sputum specimens examined. While the present study indicates a possible association between Ascaris and asthma in children, further studies, including provocation tests and controlled anthelminthic drug trials, are required to confirm, as well as elucidate this association. It is however, suggested that routine screening for helminthiasis be undertaken in asthmatic children in the tropics and deworming carried out in those with positive results.

Adolescent↗
PubMed1981

Skin sensitivity reactions in Nigerian children with bronchial asthma.

Skin sensitivity reactions to a variety of antigens in 290 unselected urban Nigerian children suffering from bronchial asthma of varying severity, are reported. The percentages of positive skin reactions to the first four antigens were as follows: Ascaris (25%), Dermatophagoides pteronyssinus (21%), house dust (12%) and feathers (12%). The sizes of reaction were generally smaller than those reported in European and American children. While the relatively high sensitivity to Ascaris was probably fortuitous, further studies are needed to evaluate the actual role, if any, of the parasite in bronchial asthma affecting the African child. The relatively low rate of positive skin reactions indicate that, at present, skin sensitivity tests are of limited value in the identification of aetiological factors in asthma affecting Nigerian children. The development of local materials for skin testing may however enhance the usefulness of this investigation in future.

Adolescent↗
PubMedDate not supplied

Plasma vitamin C (ascorbic acid) levels in asthmatic children.

Plasma concentration of ascorbic acid was determined in fifty-one asthmatic children and a group of matched controls. The mean ascorbic acid level of 0.54 mg/100 ml among the asthmatics was significantly lower than a mean of 0.84 mg/100 ml for controls (P less than 0.001). Ascorbic acid level was directly related to the socio-economic class (SC) since asthmatic children from SC I, II and II had significantly higher ascorbic acid levels than those from SC IV and V. There was however, no relationship between the plasma ascorbic acid level and atopy, frequency of asthmatic attacks over the previous 12 months and the duration of asthma. It is postulated that if plasma ascorbic acid level was related to the susceptibility to viral respiratory tract infections, the observed low level of the vitamin in the asthmatics would make them more liable to such infections which are capable of precipitating acute asthmatic attacks. Confirmation of our results would indicate the need for regular ascorbic acid supplement in some children with bronchial asthma.

Adolescent↗
PubMedDate not supplied

Serum alpha 1-antitrypsin levels in asthmatic children.

Serum levels of alpha 1-antitrypsin (AAT) were determined by an enzymatic assay method in fifty-five asthmatic children and in the same number of controls. The mean AAT level was significantly lower in asthmatics (1.65 mumol/min/ml) than in controls (2.0 mumol/min/ml) (P less than 0.02). A significantly higher proportion of asthmatics than controls (P less than 0.05) had levels below 2.1 mumol/min/ml which is the lower limit of normal, thus suggesting a higher prevalence of partial (heterozygous) AAT deficiency in the asthmatics. There was no relationship between the mean AAT levels and age, duration of asthma or frequency of asthmatic attacks. Although there is some controversy about the relationship between heterozygous AAT deficiency and pulmonary disease, severe (homozygous) AAT deficiency has been linked with emphysema which is also a complication of asthma. There was however, no evidence of emphysema in either the asthmatic child or the control who had no detectable serum AAT. There were three asthmatics whose chest radiographs showed hyperinflation, but had a mean AAT level that was not significantly different from that in those without such changes. Further studies, including phenotype determination in a larger group of asthmatic children, are required in order to determine the prevalence of both homozygous and heterozygous AAT deficiencies which may be risk factors in the development of emphysema and other pulmonary complications of asthma.

Adolescent↗
PubMedDate not supplied

Serum IgG, IgA and IgM in asthmatic children.

Serum levels of immunoglobulins G, A and M were determined in forty-five asthmatic children and in the same number of controls. Mean IgG and IgA levels in the asthmatics were not significantly different from those in the controls. Conversely, mean IgM values in female controls and all the controls taken as a group, were significantly higher than those in their asthmatic counterparts. There was no relationship between severity of asthma and the mean levels of the various immunoglobulins. However, the mean IgG value in asthmatic children with positive skin sensitivity tests was significantly higher than the mean value in those who had negative reactions. It is concluded that the serum levels of these immunoglobulins are of limited value in either the diagnosis of asthma or in the grading of its severity.

Asthma↗