RESUMEN
Experimental and clinical investigations on the possibility of reducing the antigenic content of the vaccine intended for the immunization of newborn infants have been made. Experiments on guinea pigs and white mice have demonstrated that the reduced dose of the preparation, twice as low by weight (0.025 mg), produces the same level of protection against tuberculosis as the full dose (0.5 mg). A new preparation with reduced antigenic content, vaccine BCG-M, has been developed, the technical specifications for this preparation have been approved, and its serial production has been allowed. Clinical tests have revealed that the use of the new preparation makes it possible to decrease the occurrence of unusual postvaccinal reactions and complications (lymphadenitis, ulceration) 3-fold and at the same time to increase the coverage of infants by primary immunization against tuberculosis by 7-8% annually. Since January 1986 this vaccine has been introduced into medical practice.
Asunto(s)
Antígenos Bacterianos/administración & dosificación , Vacuna BCG/administración & dosificación , Inmunización/métodos , Tuberculosis Pulmonar/prevención & control , Animales , Antígenos Bacterianos/toxicidad , Vacuna BCG/efectos adversos , Preescolar , Relación Dosis-Respuesta Inmunológica , Evaluación de Medicamentos , Evaluación Preclínica de Medicamentos , Cobayas , Humanos , Lactante , Recién Nacido , Ratones , Prueba de TuberculinaRESUMEN
The myocardium of the cardiac ventricle was studied light optically and electron microscopically in the loach (Misgurnus fossilis). After the cardiac wall was cut, it could be observed that the wound was filling with a blood clot, the muscular tissue of its edges was in the state of necrosis and necrobiosis, richly infiltrated with the blood forming elements. The tissue mentioned was surrounded with a bordering zone, its cells were undergoing peculiar reversible distrophic and reactive changes. On the 5--7th day after the injury, in the bordering zone, a reversible development of the distrophic changes and a partial structural dedifferentiation of the cardiomyocytes occurred and, as the result, they acquired a resemblance with the cells of the embryonal myocardium. In myocytes all the stages on formation of the contractile system and hypertrophy of the preserving myofibrils could be observed. In no experiment the muscular tissue was newly formed; local regeneration of the cardiac muscle in the place of its destruction did not occur. The integrity of the cardiac wall was restored at the expense of the connective tissue.