ABSTRACT
Nonadherence was associated with nondisclosure of positive HIV status. The rate was reduced among participants reporting no difficulty in taking medication as prescribed.
Subject(s)
Antiretroviral Therapy, Highly Active/statistics & numerical data , HIV Infections/prevention & control , Medication Adherence/statistics & numerical data , Adult , Cameroon , Cross-Sectional Studies , Disclosure , Female , Humans , Logistic Models , Medication Adherence/psychology , Pregnancy , Surveys and Questionnaires , Young AdultABSTRACT
A rapid method that permits separation of grape seed proanthocyanidins according to their polymerization degrees has been developed. This method was based on liquid/liquid extraction and relative solubility of these compounds in different solvents (water, ethyle acetate, methanol, and chloroform). The different fractions obtained were then analyzed by various HPLC techniques (normal phase, reversed phase after thiolysis, and gel permeation) to determine their mean degree of polymerization (DP) and molecular weight profiles. Results show that this method can be used on a preparative scale to separate these polymers according to their sizes.
Subject(s)
Anthocyanins/isolation & purification , Antioxidants/isolation & purification , Fruit/chemistry , Proanthocyanidins , Seeds/chemistry , Chromatography, Gel/methods , Chromatography, High Pressure Liquid/methods , Molecular WeightABSTRACT
The initial expression of the gene encoding tyrosine hydroxylase (TH) was studied in the trunk of quail embryos by in situ hybridization. We detected the presence of quail TH mRNA on embryonic day 3.5 (E3.5) in the sympathetic ganglia and aortic plexus, both neural crest derived structures. In contrast, the TH gene was expressed much earlier in the endodermal layer of E2 embryos, i.e. from the 8-somite stage onwards. TH mRNA was found also in the pancreatic bud, an endoderm-derived structure. The TH protein and catecholamines were subsequently looked for in these structures. TH immunoreactivity was found in cells of E2 explanted endoderm, but no catecholamine histofluorescence was observed before or after a few days in culture. TH-positive cells were also detected in cultures of pancreatic rudiments, explanted from E3 to E6 quail embryos. We suggest that the TH-positive cells of the endoderm are the progenitors of the catecholaminergic cells of the pancreas and of the enterochromaffin cells of the gut. The hypothesis that the TH-positive cells of the endoderm are involved in the expression of the catecholaminergic phenotype by neural crest cells is discussed.
Subject(s)
Coturnix/embryology , Endoderm/enzymology , Pancreas/enzymology , Tyrosine 3-Monooxygenase/genetics , Animals , Catecholamines/analysis , Catecholamines/genetics , Catecholamines/immunology , Cell Differentiation/physiology , Cells, Cultured , Coturnix/genetics , Endoderm/chemistry , Endoderm/cytology , Fluorescent Antibody Technique , Gene Expression Regulation, Enzymologic , Immunohistochemistry , In Situ Hybridization , Neural Crest/chemistry , Neural Crest/cytology , Pancreas/chemistry , Pancreas/cytology , RNA, Messenger/analysis , RNA, Messenger/genetics , Tyrosine 3-Monooxygenase/analysis , Tyrosine 3-Monooxygenase/immunologyABSTRACT
The retina is an integral part of the central nervous system, and consists of two layers, the outer pigmented layer and the inner sensory layer or neuroretina (NR). The NR layer contains several strata of cells (glial and neuronal) derived from proliferating neuroectodermal precursors that differentiate after terminal mitosis. In vitro, NR cells can differentiate not only into neuronal and glial types, but also into pigment and lens cells. Quail (Coturnix coturnix japonica) NR cells (QNR) infected with MC29 transforming retrovirus become pigmented after several passages in vitro. In order to characterize the genes expressed in these pigmented MC29 QNR, a cDNA library was prepared from these cells. After differential screening we have isolated a cDNA clone which identifies an RNA expressed in NR but not in the pigmented layer of the retina. This cDNA encodes a protein related to that of Drosophila, mouse and zebrafish paired box- and homeobox-containing segmentation genes and is called Pax-QNR. The expression of Pax-QNR in the NR is confined to the ganglionic cell layer and to the lower part of the inner nuclear layer containing the amacrine or correlation neurones.
Subject(s)
Coturnix/genetics , Gene Expression , Genes, Homeobox , Retina/metabolism , Amino Acid Sequence , Animals , Base Sequence , DNA/isolation & purification , Gene Library , Molecular Sequence Data , Mutation , Nucleic Acid Hybridization , Organ SpecificityABSTRACT
We have used in situ hybridization to study the spatial and temporal distribution of the transcription of three cellular oncogenes encoding DNA-binding proteins, c-ets 1, c-myb and c-myc during the development of the chick embryo. c-ets 1 mRNA expression appears linked to the mesodermal lineage and is strongly expressed in early endothelia; it subsequently becomes restricted to small vessel endothelia. Hemopoietic cells in extraembryonic blood islands at E2 express c-ets 1, while intraembryonic hemopoietic cells in aortic clusters (E3) and paraaortic foci (E6) express c-myb. c-myc transcripts are detected in cells undergoing hemopoiesis in both these extraembryonic and intraembryonic sites. Outside the blood-forming system, c-myc is transcribed in a large variety of cells; c-ets 1 displays tissue-specific expression in groups of mesodermal cells engaged in morphogenetic processes and appears excluded from all epithelia; finally the expression of c-myb is the most tightly linked to hemopoietic cells. In any case, it is clear that these three oncogenes display complementary expression in endothelial and hemopoietic cells where their patterns are modulated in relationship to multiplication and differentiation.
