ABSTRACT
In a previous study we were able to show that in women over the age of 45 the level of 1,25-dihydroxyvitamin D (1,25(OH)2D) in bone, but not in serum, is significantly reduced when compared with younger women. In the present study we measured the concentration of 1,25(OH)2D in sera and bones of 19 female patients with subcapital fractures of the femur, mean age 78 +/- 2 years. We were able to show that serum levels of 1,25(OH)2D were within the normal range, while bone levels were markedly reduced compared to levels in femoral bone obtained from young female cadavers or to the previously reported levels in non-osteoporotic elderly women. Thus, reduced levels of 1,25(OH)2D in bones of elderly women may lead, together with other factors, to subcapital fractures.
Subject(s)
Femur Neck/chemistry , Vitamin D/analysis , Adult , Aged , Blood Chemical Analysis , Cadaver , Calcium/metabolism , Female , Femoral Neck Fractures/etiology , Humans , Osteoporosis/complicationsABSTRACT
Blocks of bovine enamel subjected to de- and remineralization were measured for changes in permeability to iodide and urea. Results were similar, indicating that the diffusion pathways for the two species were comparable, and that sites for iodide binding did not appear to exit.
Subject(s)
Dental Enamel Permeability/drug effects , Iodides/pharmacology , Tooth Calcification/drug effects , Tooth Permeability/drug effects , Urea/pharmacology , Animals , Cattle , Dental Caries/physiopathology , Dental Enamel/drug effects , Dental Enamel/physiologySubject(s)
Actinomyces , Alveolar Process/drug effects , Gingiva/drug effects , Gingivitis/chemically induced , Lipids/toxicity , Streptococcus mutans , Actinomyces/analysis , Alveolar Process/pathology , Animals , Gingiva/pathology , Gingivitis/pathology , Glycolipids/administration & dosage , Glycolipids/isolation & purification , Glycolipids/toxicity , Lipids/administration & dosage , Lipids/isolation & purification , Lymphocytes/pathology , Mouth Mucosa/drug effects , Mouth Mucosa/pathology , Neutrophils/pathology , Osteoblasts/pathology , Osteocytes/pathology , Phospholipids/administration & dosage , Phospholipids/isolation & purification , Phospholipids/toxicity , Rats , Streptococcus mutans/analysisABSTRACT
The presence of the isoprenoid squalene, synthesized de novo, was demonstrated in 64 out of 73 strains of gram-positive bacteria by thin-layer chromatography. This observation was confirmed by gas-liquid chromatography, chemical reactivity, incorporation of radiolabeled precursor, and by gas chromatography mass spectroscopy of thin-layer chromatography-recovered material.
Subject(s)
Bacteria/analysis , Mouth/microbiology , Squalene/analysis , Bacteria/metabolism , Chromatography, Thin Layer , Humans , Mevalonic Acid/metabolism , Species Specificity , Squalene/biosynthesisABSTRACT
Pure cultures of a variety of bacteria were treated with ultrasonic energy using a sonic probe. Fractions of organisms killed at different sonic energies were calculated, and Streptococcus mutans was 600 times more resistant than Fusobacterium nucleatum, the most sensitive organism tested. The effects of sonic treatment on aggregates of bacteria were examined, and the results were interpreted as a model of the events that probably occur during the sonic dispersion of dental plaque.
