Cranio-osteoarthropathy in sibs.

Primary hypertrophic osteoarthropathy is a condition characterized by clubbing, arthropathy and periostosis of long tubular bones. Three variants of primary hypertrophic osteoarthropathy are distinguished: pachydermoperiostosis, which shows as additional symptom pachydermia; cranio-osteoarthropathy, which has a decreased neurocranium ossification as additional feature; and a secondary form. Primary hypertrophic osteoarthropathy is also genetically heterogeneous, with evidence for both autosomal dominant and autosomal recessive inheritance. We describe two sibs with cranio-osteoarthropathy and briefly review previously reported cases. The present cases demonstrate the phenotypic variability of the condition. The consanguinity in the present family and analysis of previously described cases support autosomal recessive inheritance for cranio-osteoarthropathy.

Intra- and extracellular pH of the brain in vivo studied by 31P-NMR during hyper- and hypocapnia.

Studies were performed to determine the pH relationships among the extracellular, intracellular, and arterial blood compartments in the brain in vivo. Resolution of the extracellular monophosphate resonance peak from the intracellular peak in 31P nuclear magnetic resonance (NMR) spectra of sheep brain with the calvarium intact enabled pH measurement in these respective compartments. Sheep were then subjected to both hyper- and hypoventilation, which resulted in a wide range of arterial PCO2 and pH values. Linear regression analysis of pH in these compartments yielded slopes of 0.56 +/- 0.05 for extracellular pH (pHe) vs. arterial pH, 0.43 +/- 0.078 for intracellular pH (pHi) vs. pHe, and 0.23 +/- 0.056 for pHi vs. arterial pH. These data indicate that CO2 buffering capacity is different and decreases from the intracellular to extracellular to arterial blood compartments. Separation of the extracellular space from the vascular space may be a function of the blood-brain barrier, which contributes to the buffering capability of the extracellular compartment. A marked decrease in the pH gradient between the extracellular and intracellular space occurs during hypercarbia and may influence mechanisms of central respiratory control.

Morphological and genetic effects of benomyl on polyploid brewing yeasts: isolation of auxotrophic mutants.

An enrichment procedure after ethyl methanesulfonate mutagenesis and exposure to the fungicide benomyl yielded mutants auxotrophic for several amino acids from two polyploid Saccharomyces spp. Benomyl treatment was found to have a marked morphological effect on polyploid Saccharomyces cerevisiae, causing cells to adopt a characteristic doublet cell morphology in which buds are nearly as large as the parent cells. Experiments in which nuclear division was monitored in benomyl-induced doublet cells by Giemsa nuclear staining demonstrated an unusual sequence of cytological events which culminated in the formation of binucleate parental and mononucleate bud components. The frequency of formation of doublet and binucleate parent cells was found to depend on the strain employed and the benomyl concentration administered.