RESUMEN
Osteoporosis (OP) is a systemic condition that has dental implications. The purpose of this study was to compare OP risk among various dental specialty subpopulations at Indiana University School of Dentistry (IUSD). A survey was administered to 220 adult female dental patients assessing menstrual status and risk behaviors associated with low bone mass. The subjects' mean age was 48.2 +/- 1.1 years (mean +/- SEM). Overall, 38% of the surveyed patients exhibited high risk for OP. The orthodontic subpopulation (a dentate group with routine developmental malocclusions) was the youngest group and contained the lowest percentage at high-risk (6%). Conversely, the complete denture subpopulation was the oldest and contained the highest percentage of patients at high risk (53%). Postmenopausal women who had inadequate hormone replacement therapy exhibited a strong negative correlation for number of teeth retained with increasing years postmenopause (r = 0.6). Patients in the implant therapy group (many of which had adjunctive orthodontic care) had a mean age similar to the complete denture group, but a much lower risk for OP. This appears to be due to the extensive counseling these patients receive prior to treatment. It is concluded that risk factor analysis and patient counseling may be effective measures for reducing the osteoporosis risk of dental patients.
Asunto(s)
Osteoporosis/complicaciones , Pérdida de Diente/etiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Terapia de Reemplazo de Estrógeno , Femenino , Necesidades y Demandas de Servicios de Salud , Humanos , Persona de Mediana Edad , Osteoporosis/clasificación , Osteoporosis/prevención & control , Factores de RiesgoRESUMEN
The degradation of muramyldipeptides (MDPs) in aqueous solution obeys the rate law kobs = kH+aH+ + ko + kHO-aHO- and the Arrhenius equation. For example, the rate constants for degradation of N-acetylmuramyl-L-threonyl-D-isoglutamine, 3, at 25 degrees C are kH+ = 2.3 X 10(-6) M-1 sec-1, ko = 8.2 X 10(-10) sec-1, and kHO- = 0.19 M-1 sec-1. The degradation rates are dependent on the side-chain substituents; it is predicted that sterically hindered MDP compounds will show an extended shelf life in aqueous solution. Product studies in the weakly acid pH region (where the pH of maximum stability occurs) show that MDP compounds degrade largely by hydrolysis of the dipeptide side chain. These data show that MDP 3 exhibits a shelf life (t90) of greater than 2 years in aqueous solutions of pH 4-4.5, the pH of maximum stability.
Asunto(s)
Acetilmuramil-Alanil-Isoglutamina/análisis , Adyuvantes Inmunológicos , Aminoácidos/análisis , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Cinética , Soluciones , TemperaturaRESUMEN
The use of multiply tritiated radiopharmaceutical compounds for long-term stability studies should be avoided because different radiolabeled products are produced by radioactive decay than by chemical degradation. This is demonstrated by showing that doubly tritiated fluocinolone acetonide and (14)C-labeled fluocinolone acetonide have different shelf lives and that the tritiated compound affords additional degradation products not seen in reaction of the (14)C-labeled drug after 26 months.
RESUMEN
A rapid and sensitive spectrophotometric method has been developed to quantitate the peroxides present in sorbitan monooleate and monostearate. The method relies on the peroxide conversion of iodide to iodine. The method has also been found to work for polysorbate 60.
Asunto(s)
Hexosas/análisis , Peróxidos/análisis , Espectrofotometría/métodosRESUMEN
Phenylhydroxylamine is degraded in aqueous phosphate buffers at physiological pH values (6.8-7.4) to give nitrosobenzene, nitrobenzene, and azoxybenzene. The reaction is O2 dependent and subject to general acid and general base catalysis. At pH less than or equal to 5.8 in cacodylate buffer, it is converted to p-nitrosophenol in addition to nitrosobenzene, nitrobenzene, and azoxybenzene. Nitrobenzene and p-nitrosophenol appear to form directly from phenylhydroxylamine. A common intermediate generated from phenylhydroxylamine and O2 is suggested to account for the formation of nitrobenzene, nitrosobenzene, and p-nitrosophenol and is consistent with kinetic studies and 18O-labeling experiments. The results suggest that neither hydrogen peroxide nor superoxide (O-2) are involved in the oxidation sequence.