Genetic heterogeneity and minor CYP1B1 involvement in the molecular basis of primary congenital glaucoma in Gypsies.

Primary congenital glaucoma (PCG) is a genetically heterogeneous disorder of autosomal recessive inheritance, with mutations in the cytochrome P450 1B1 (CYP1B1) gene detected in an average of approximately 50% of cases worldwide. The Roma/Gypsies are considered to be a rare example of a single founder CYP1B1 mutation, E387K (identified in the Slovak Roma), accounting for 100% of disease alleles. Contrary to this concept, unusual genetic heterogeneity was revealed in this study of 21 Gypsy PCG patients from Bulgaria and 715 controls from the general Gypsy population. In our small sample of affected subjects, we identified five different CYP1B1 mutations - four known (E229K, R368H, E387K and R390C) and one novel and potentially pathogenic (F445I), which together accounted for approximately 30% of disease alleles. E387K was rare in both the patient and the control group, indicating that its high frequency in the Slovak Roma is the product of local founder effect not representative of the overall molecular pattern of PCG in the Gypsy population. Data on other Mendelian disorders and on the population genetics of the Gypsies suggest that a true founder mutation is likely to exist and has remained undetected. Our analysis of another candidate gene, MYOC, and the GLC3B and GLC3C loci did not provide support for their involvement. The molecular basis of PCG in the Gypsies is thus unresolved, and diagnostic analyses should be extended beyond the E387K mutation.

Opinion of South African Pre- and Post-Menopausal Women on the Potential Menopause-Related Health Benefits of Soy and Soy products

The increased use of alternative treatment for menopausal symptoms is mainly due to women's changing opinions of conventional hormone replacement therapy (HRT). The objective of this study was to assess the opinion of preand post-menopausal South African women regarding the potential menopause-related health benefits of soy. The sample used for the study was a sub-dataset of 825 respondents; which included only pre- and post-menopausal women that had heard of soy before; selected from a representative sample of the adult South African metropolitan and rural populations. A structured questionnaire was used. Neither age nor racial groups differed practically significantly in opinion regarding any of the various statements. The study also shows that a practically significant lower proportion of women in the sub-population across both age and race groups had a positive opinion on the health benefits of soy as an alternative to HRT and reliever of menopausal symptoms than those who acknowledged its benefit for preventing cardiovascular disease and osteoporosis. Practically significantly more women who used soy than women who never used soy agreed that soy keeps bones strong. In addition; more women who were of opinion that soy has few or no health benefits disagreed that soy could be used as an alternative to HRT compared to women who held a positive opinion

HIV-positive and HIV-negative consumers accept an instant soy maize porridge

The objective of this study was to assess consumer acceptability; preference and consumption intent of an instant soy maize porridge; compared to an instant plain maize porri- dge; in order to determine the successful inclusion of the soy maize porridge as a food supplement for HIV subjects in a subsequent nutrition intervention trial; to improve their nutritional status. A 5-point hedonic and food action rating scale was used for this purpose. HIV-positive (n=57) and HIV-negative (n=47) subjects were recruited on a basis of availability and willingness to participate. Long-term acceptability and compliance of HIV-positive consumers (n=9) was assessed after three and five months. Analysis of variance (ANOVA); Tukey's multiple comparison test and T-tests (p=0.05) were performed. Overall; consumers found the soy maize porridge significantly more acceptable; preferred it to; and also intended to consume it more often than the plain maize porridge. There were no significant differences between the HIV-positive and HIV-negative group regarding acceptability; preference and consumption intent. After three and five months; the HIV-positive consumers (n=9) did not find acceptability of the soy maize porridge significantly different from the first evaluation. It therefore had the potential to be included successfully in the nutrition intervention trial. The current study emphasises the need for sensory evaluation of food products prior to including them in intervention studies; to assess consumers' acceptance of them

Reaction rates of oxygen with hemoglobin measured by non-equilibrium facilitated oxygen diffusion through hemoglobin solutions.

The purpose of this study was to verify the concept of non-equilibrium facilitated oxygen diffusion. This work succeeds our previous study, where facilitated oxygen diffusion by hemoglobin was measured at conditions of chemical equilibrium, and which yielded diffusion coefficients of hemoglobin and of oxygen. In the present work chemical non-equilibrium was induced using very thin diffusion layers. As a result, facilitation was decreased as predicted by theory. Thus, this work presents the first experimental demonstration of non-equilibrium facilitated oxygen diffusion. In addition, association and dissociation rate parameters of the reaction between oxygen and bovine and human hemoglobin were calculated and the effect of the homotropic and heterotropic interactions on each rate parameter was demonstrated. The results indicate that the homotropic interaction--which leads to increasing oxygen affinity with increasing oxygenation--is predominantly due to an increase in the association rate. The heterotropic interaction--which leads to decreasing oxygen affinity by anionic ligands--appears to be effected in two ways. Cl- increases the dissociation rate. In contrast, 2,3-diphosphoglycerate decreases the association rate.

Diffusion coefficients of oxygen and hemoglobin measured by facilitated oxygen diffusion through hemoglobin solutions.

Diffusion coefficients of oxygen (DO2) and hemoglobin (DHb) were obtained from measuring the oxygen flux through thin layers of hemoglobin solutions at 20 degrees C. The liquid layers were supported by a membrane and not soaked in any filter material. Oxygen fluxes were measured from the changes in oxygen partial pressure in the gas phases at both sides of the layer. A mathematical treatment is presented for correct evaluation of the measurements. Measurements were done for bovine and for human hemoglobin. Hemoglobin concentrations (CHb) were between 11 and 42 g/dl, which covers the concentrations in the erythrocyte. Both DO2 and DHb could be fitted to the empirical equation D = D0(1-CHb/C1)10-CHb/C2. The following parameters were obtained: DO = 1.80 x 10(-9) m2/s, C1 = 100 g/dl, C2 = 119 g/dl, for oxygen and D0 = 7.00 x 10(-11) m2/s, C1 = 46 g/dl, C2 = 128 g/dl, for hemoglobin. No difference between the diffusion coefficients of bovine or human hemoglobin was found. The diffusion coefficients of hemoglobin were higher than most values reported in the literature, probably because in this study the mobility of hemoglobin was not hindered by surrounding filter material.