Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After having described in detail the pathophysiology, symptomatology, X-chromosomal inheritance and some laboratory methods in detecting G-6-PD-deficiency by demonstrating a case of favism (Schulz et al. 1977), the authors now discuss the particularities of the enzyme deficiency in the newborn. These are complicated by additional physiological and transient deficiency of the enzymes catalase, NAD-diaphorase, glutathione peroxidase, and glucuronyl transferase. Several chemical substances, acidosis, hypoxia, hypoglycemia, and immaturity may cause a severe hyperbilirubinemia in G-6-PD-deficient newborns. The development of a kern-icterus in these cases may be prevented by early exchange transfusion. From clinical findings and some observations in different regions of Greece an additional factor influencing the liver function has been postulated which favors the development of hyperbilirubinemias in G-6-PD-deficient newborns. The nature of this possible factor is discussed. The authors emphasize the necessity of screening for G-6-PD-deficiency during pregnancy in families of mediterranian descent.
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PMID:[Glucose-6-phosphate dehydrogenase deficiency of the mediterranean type B minus. 2. Etiological basis for severe hyperbilirubinemia in the newborn]. 63 93

The ultrastructure of feline yolk sacs from 11 stages between the 14th and the 66th day is described with reference to the endoderm and the mesothelium; supplementary histochemical and cytochemical studies are included. Despite the absence of yolk, the endodermal epithelium shows a high degree of differentiation and activity, especially in the period between the 25th and the 38th day. Large stacks of RER, abundant SER, mitochondria enveloped by RER cisternae, and a peculiar type of lysosome are the most prominent organelles. Acid phosphatase, succinic dehydrogenase and NAD- and NADP-diaphorases are found with high activity, whereas the 17beta-hydroxysteroid dehydrogenase assay stains the endothelium only moderately. Indications of reabsorption are less marked. In view of the apparent immaturity of the liver parenchymal cells at this stage, the yolk sac endoderm of cat is suggested to act as an important extraembryonic site of biosynthesis. As preliminary results of a chemical analysis show that the yolk sac fluid has nearly no nutritional value, the substances synthesized are believed to be transported directly to the fetus. The mesothelium shows relatively few alterations over the period studied, is less rich in organelles and is obviously far less active than the endoderm.
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PMID:On the yolk sac of the cat. Endoderm and mesothelium. 103 35

This review explores the potential for changes in dietary macronutrients to differentially influence mitochondrial bioenergetics and thereby the frequency of mtDNA haplotypes in natural populations. Such dietary modification may be seasonal or result from biogeographic or demographic shifts. Mechanistically, mtDNA haplotypes may influence the activity of the electron transport system (ETS), retrograde signalling to the nuclear genome and affect epigenetic modifications. Thus, differential provisioning by macronutrients may lead to selection through changes in the levels of ATP production, modulation of metabolites (including AMP, reactive oxygen species (ROS) and the NAD(+)/NADH ratio) and potentially complex epigenetic effects. The exquisite complexity of dietary influence on haplotype frequency is further illustrated by the fact that macronutrients may differentially influence the selective advantage of specific mutations in different life-history stages. In Drosophila, complex I mutations may affect larval growth because dietary nutrients are fed through this complex in immaturity. In contrast, the majority of electrons are provided to complex III in adult flies. We conclude the review with a case study that considers specific interactions between diet and complex I of the ETS. Complex I is the first enzyme of the mitochondrial ETS and co-ordinates in the oxidation of NADH and transfer of electrons to ubiquinone. Although the supposition that mtDNA variants may be selected upon by dietary macronutrients could be intuitively consistent to some and counter intuitive to others, it must face a multitude of scientific hurdles before it can be recognized.
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PMID:Review: can diet influence the selective advantage of mitochondrial DNA haplotypes? 2654 31