RESUMEN
We evaluated the efficiency of a lubricant based on a pulmonary surfactant in experimental knee osteoarthritis in rats induced by intraarticular injection of abrasive material that reduces the lubricative properties of the synovial fluid. Experimental substance containing proteins of the pulmonary surfactant exhibiting natural lubricative properties was used as the lubricant. The effectiveness of the substance was analyzed by changes in morphological characteristics of the articular cartilage in 3D reconstruction images of the knee joint obtained by the method of multiple high-precision grinding. It was found that radial thickness of the articular cartilage increased and surface relief index decreased on the 6th and 12th week after administration of the substance containing surfactant proteins, which can indicate partial recovery of the articular cartilage.
Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Articulación de la Rodilla/diagnóstico por imagen , Lubricantes/administración & dosificación , Lubricantes/uso terapéutico , Surfactantes Pulmonares/administración & dosificación , Animales , Cartílago Articular/química , Inyecciones Intraarticulares , Masculino , Osteoartritis de la Rodilla , Surfactantes Pulmonares/uso terapéutico , Ratas , Ratas WistarRESUMEN
Measurements of gaseous elemental mercury (Hg0) in the marine boundary layer of the western Bering Sea were performed using an automatic mercury analyzer RA 915+ (Ltd. "Lumex", St. Petersburg, Russia) aboard the Russian research vessel Academician M.A. Lavrentev from 3 to 20 August 2013. Hg0 concentrations varied from 0.3 to 2.1ng/m3 (n=4783); the average value (1.1±0.3ng/m3) was lower than both the background range of the Northern Hemisphere (1.5-1.7ng/m3) and average values previously observed in the Bering Sea, and corresponded to the background concentrations of the Southern Hemisphere (1.1-1.3ng/m3). Maximum Hg0 concentrations were observed within air masses that came from the lower troposphere of the central Arctic. Under these conditions, Hg0 ranged between 1.1 and 2.1ng/m3 with an average of 1.5±0.2ng/m3 (n=1183). Except for these periods, Hg0 concentrations during the rest of the study varied from 0.3 to 1.8ng/m3, with an average value of 1.0±0.2ng/m3 (n=3600). Our results support the hypothesis that, in the summer, air masses from the central Arctic Ocean can be an exporter of mercury to lower latitudes. Perhaps the atmospheric transport of elevated concentrations of Hg0 into lower latitudes may have implications for the biologic and economic health of important fisheries, such as the Bering Sea.
Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Mercurio/análisis , Regiones Árticas , Atmósfera/química , Estaciones del AñoRESUMEN
A retrospective epidemiological analysis of hepatitis A morbidity for many years among the population of two neighboring towns in the temperate climatic zone of the USSR has revealed the cyclic character of the epidemic process without a perceptible decrease in its extensiveness and has determined the high-risk groups, as well as the beginning of the seasonal rise of morbidity in these groups. The results of the study indicate that different levels of hepatitis A morbidity and risk groups can be observed in these two neighboring towns. At periods of a lower morbidity level the high-risk group embraces schoolchildren, and when morbidity is at a higher level the risk group includes schoolchildren and preschool children in organized groups. Among the latter the morbidity level is influenced by factors acting all the year round and among school children, by seasonal factors. The beginning of the seasonal rise of morbidity falls on August, while in organized groups of children of preschool age the seasonal rise of hepatitis A morbidity begins 1-1.5 months later. All prophylactic measures for controlling hepatitis A should be carried out with due regard to these features of the epidemic process.