Different reactivity of two rabbit vessels under hypoxia.

The effect of hypoxia on isolated rabbit vessel reactivity to vasoconstrictive agents was studied. Short-lasting hypoxia (30 min.) enhanced the responses to noradrenaline, 5-hydroxytryptamine, histamine and endothelin in the ear artery. Increased reactivity was also found with KCl depolarization solution. Deendothelization of the ear artery did not influence the enhanced responses to noradrenaline and endothelin in hypoxia. In similar experimental conditions the femoral artery reactivity to noradrenaline was not affected by hypoxia, the constrictory responses to 5-hydroxytryptamine were decreased. It can be concluded that hypoxic facilitation of vasoconstrictive activity is probably independent on receptor-related mechanisms and/or on the presence of endothelium. The results obtained confirm also the difference in reactivity of rabbit vessels from two vascular beds to vasoconstrictive agents under hypoxia.

[Surveillance of tuberculosis in the Czech Republic in 1991]. / Dohled nad tuberkulózou v Ceské republice v roce 1991.

They authors present an interim report on the epidemiological situation of tuberculosis and the effectiveness of control measures as regards tuberculosis in the Czech Republic in 1991. The data are compared with previous years. The incidence of tuberculosis of all forms was 19.9/100,000 population, TB of the respiratory organs 16.2/100,000 and the incidence of bacteriologically confirmed respiratory TB 11.5/100,000 population. As compared with previous years, no statistically significant differences were found. Extrapulmonary TB accounted for less than 10% of the incidence, the position was similar also as regards mycobacterioses other than TB. The incidence of TB in children was 1.3/100,000 children under 15 years, after a transient increase in 1990 (microepidemic in gypsy children), a marked decline was recorded. The TB mortality rate was low (1.1/100,000 population), the prevalence to the date of Dec. 31 1991 was 21.7/100,000 population. On account of complaints 76% new cases were detected, the majority within 1 month, antituberculous treatment was effective, the mean period of treatment was reduced to less than 8 months. However, long in-patient treatment persists usually at the beginning of antituberculous treatment (3 months).

Endothelial changes following repeated effect of vasoconstrictive substances in vitro.

Using perfusion method the reactivity of rabbit femoral and ear arteries was investigated following the administration of rising noradrenaline doses in four consecutive intervals. Progressive increase of vasoconstrictive activity of vessel segments was found. Results of histological examination showed a progressive de-endothelialization of perfused vessels. The loss of endothelium increased depending on time of action and on intensity of vasoconstrictive stimuli.

[Measuring the effectiveness of different variants of tuberculosis control using simulation models]. / Messung der Effektivität verschiedener Varianten der Tuberkulosebekämpfung mit Hilfe von Simulationsmodellen.

Simulation and predictive models of tb epidemiological trends in the Czech Socialist Republic (CSR) for the 1949-2000 period were devised taking into account several variants of tb control measures. AZUMA'S simulation model from Japan was used as the basis for the mathematical processing and adapted in different parts to satisfy the conditions prevailing in the CSR. The initial conditions and parameters to go into the equations of the model were determined or estimated from statistical data for the whole of CSR or from the results of some of the more detailed partial studies. An Olivetti P 6060 minicomputer was used for calculations. Statistical data were found in satisfactory agreement with trends estimated from model simulations. The simulation models revealed that the epidemiological trends were most influenced by the treatment, less by the BCG vaccination and the least by the active case finding. As suggested by the predictive simulations, discontinuation of the programme of tb control would result in a major deterioration of the epidemiological situation.

[Development of the tuberculosis situation in Czechoslovakia in 1966--1974 (author's transl)]. / Entwicklung der Tuberkulose-Situation in der Tschechoslowakei in den Jahren 1966--1974

There were declining trends of main epidemiological indices of tuberculosis in Czechoslovakia from 1966 to 1974 (Fig. 1 and 2). The smallest average yearly decrease of 4.9% was in the incidence of newly detected cases of active tuberculosis, the largest one of 21.6% in the prevalence of "tuberculous chronics" excreting tubercle bacilli in the last two years or longer. The total of newly detected cases of active tuberculosis and relapses per 100,000 inhabitants of corresponding groups of sex and age decreased in 1966--1974 in nearly all age groups of both sexes, the highest rates being in persons aged 45 years and over (Fig. 3). The participation of corresponding groups of population in BCG vaccination procedures was very high at the national scale during 1966--1974. The highest relative number of active cases of respiratory tuberculosis newly detected by photofluorography per 100,000 examinees of the appropriate group was found in persons with "fibrotic" lung lesions, less in persons investigated for their symptoms, still less in contacts with tuberculosis cases and least in persons not registered for lung lesions and investigated in mass X-ray examinations. The number of beds in institutions for special care of tuberculosis and respiratory diseases per 1,000 population by the end of the corresponding year decreased in Czechoslovakia from 1.1 in 1966 to 0.8 in 1974. The decrease of rates of tuberculous patients was accompanied by a decrease of the number of cases under ambulatory chemotherapy of tuberculosis. At the same time there was an increase in the number of cases treated for nontuberculous respiratory diseases in out-patients' and in-patients' departments of tuberculosis and respiratory diseases. In spite of the favourable epidemiological development of tuberculosis there remain large groups of the population -- especially in middle and higher age groups -- infected with tuberculosis in the past in which new cases of active tuberculosis may appear.

Epidemiological and clinical study of tuberculosis in the district of Kolín, Czechoslovakia. Second report (1965-1972).

An epidemiological and clinical study of tuberculosis in a district with a population of 100 000 has been in operation in Czechoslovakia since 1960. Its objective is to ascertain the epidemiological situation and long-term trend in respect of tuberculosis in a country with well-established tuberculosis control facilities. This second report presents the results achieved in the period 1965-72 and the epidemiological trend of tuberculosis observed during the 12-year study period. The fundamental control measures adopted during the study included systematic BCG vaccination of the newborn and revaccination of persons aged 14 and 19 years; mass surveys of the population over 14 years of age by photofluorography; case-finding among persons with symptoms and in risk groups; systematic treatment of all persons with active tuberculosis-i.e., supervised inpatient treatment followed by outpatient self-administered regimens; and radiological and bacteriological follow-up of cases.The results confirmed that the systematic application of effective treatment throughout the study population was followed by a rapid decline in the prevalence of bacillary tuberculosis, particularly in its chronic form. The incidence of bacillary tuberculosis declined more slowly, because the risk of contracting the disease continued to be high for middle-aged and elderly persons. Indiscriminate photofluorographic surveys of the study population at 3-yearly intervals produced a decreasing yield.An increasing proportion of noninfected persons among the population is the basic condition for a further decline of tuberculosis. The cost of tuberculosis control can be reduced by strict adherence to rational and economical working methods. Most of the economic indicators analysed fell to less than one-fifth between 1961 and 1972.

Alergia tuberculinica en personas en contacto con la fuente humana de tuberculosis

Los autores demuestran en un grupo de niños con contacto con la fuente (en el grupo correspondiente de control) las posibilidades de aprovechamiento epidemiologico de las pruebas standard tuberculinicas en la poblacion vacunada. Comparan la alergia tuberculinica de los niños en contacto con la fuente con alergia tuberculinica del grupo de control en dependencia de la edad del niño y del numero de habitantes en el domicilio. (AU)