Isoniazid Chemoprophylaxis of Tuberculosis

A major step toward the eradication of tuberculosis in the United States has been the use of isoniazid for chemoprophylaxis in certain persons who have positive tuberculin skin tests but no other evidence of active infection. Chemical trials have demonstrated the effectiveness of chemoprophylaxis in groups where there is a relatively high risk of active tuberculosis. However, only the practicing physician can identify and offer chemoprophylaxis to many other susceptible persons. Even if the patient is a candidate for isoniazid, the risk of developing tuberculosis must be weighed against the cost and possible adverse effects of the drug. If isoniazid is given, the physician must be alert to the signs of possible drug toxicity. If isoniazid is not given, he must anticipate the development of active tuberculosis in susceptible persons.     

Epidemiological and immunological features of tetanus under conditions of long-term planned vaccine prophylaxis

The introduction of mass immunization against tetanus has resulted in the decrease of morbidity rate (5.2 times), the leveling of morbidity rate among the urban and rural population and among males and females, though no essential effect on the seasonal distribution of tetanus morbidity has been observed. Persons over 50 years of age (housewives and pensioners) have become the main groups of risk at the post-immunization period. Mass immunization against tetanus over a period of many years has ensured the existence of a sufficient immune stratum (89.9 +/- 3.0% to 100 +/- 3.0%) and a sufficient level of antitoxic immunity (means geom equal to 6.72-9.6 I.U./ml) among children. Among adults, the proportion of persons protected from tetanus decreases in older age groups from 82.1 +/- 1.3% in persons aged 31-40 years to 22.1 +/- 2.0% in persons over 60 years. The observed differences between the coverage of the population with immunization and the proportion of persons having protective titers of tetanus antibodies require constant control of the intensity of immunity and its correction with regard to its initial level, especially in persons of older age groups.     

Detection of individuals within a group of risk for meningococcal infection morbidity in organized collectives

The survey of 2,500 persons in different educational organized groups has been carried out by the method based on the study of changes occurring in the standard population of group A meningococci due to its interaction with the surviving culture of human leukocytes. The heterogeneity of humans with regard to the individual antimeningococcal activity of their blood irrespective of their levels of humoral immunity and complement activity has been revealed. The survey has shown the possibility of detecting the groups of risk among the members of organized groups having, according to our data, a significantly higher level of morbidity in generalized meningococcal infection and meningococcal carriership (including epidemiologically important groups A, B and C).     

Improved predictive testing for Huntington disease by using three linked DNA markers.

Eighty-five persons at risk for Huntington disease (HD) have enrolled in a predictive-testing pilot program. Informativeness of the test has been determined for 41 of these candidates by using linked DNA probes. Nine (21.9%) of these persons have been excluded from the test as a result of the unavailability of DNA from crucial family relatives. Homozygosity for all of the three DNA markers (D4S10, D4S62, and D4S95) was not found in any affected parent. Only one (2%) of the 41 test candidates has had an uninformative result. Results have been given to 20 persons, of whom 12 (60%) received a decreased risk and eight (40%) received an increased risk of having inherited the mutant gene for HD. The combined use of three DNA markers significantly increases the informativeness of family structures such that some change in the estimation of genetic risk is now possible for approximately 75% of all persons who request predictive testing.     

Thromboelastographic assays of the clotting process in situations of obesity and caloric restriction

A study on blood clotting has been carried out in a number of obese individuals and compared to a group of non-obese persons, in order to assess if the former can be considered to be in "high risk" regarding the onset of a thromboembolic process. The technique of thromboelastography was chosen. The results point out that in obese people a series of alterations take place, both in the time of clot formation, which is enlarged, as in the organization of its nets, which appear strongly structured, favoured by the hyperfibrinogenemia and thrombocytosis detected in these subjects. Likewise, the effect of a hypocaloric diet on clotting in obese persons has been evaluated and compared with the former groups. Clotting in treated obese individuals is modified in the same way as in the untreated group when compared to the non-obese population; nevertheless, when both groups of obese people are compared, no significant difference is observed in the different parameters studied, even though constants determined in citrated whole blood are closer to normality in the subjects undergoing caloric restriction.     

Mortality among the liquidators of the Chernobyl accident: dose dependences and groups of the potential risk

Dynamics of the mortality and the mortality radiation risks among male emergency workers of 1986-1987 years of entrance to the Chernobyl zone is analyzed. The average dose of external gamma-exposure for this cohort equals 128 mGy. The size of the cohort at the beginning of the follow-up in 1992 was 47820 persons. For the follow-up period 1992-2006 statistically significant radiation risks of death rates have been estimated: for the mortality from all causes, the excess relative risk per Gy (ERR/Gy) equals 0.42 with 95% confidence interval (95% CI) (0.14-0.72); for the mortality from solid cancers ERR/Gy = 0.74, 95% CI (0.03-1.76); and for the mortality from the circulatory system diseases ERR/Gy = 1.01, 95% CI (0.51-1.57). Based on these estimates the risk groups were ranked among all Russian emergency workers (160 thousand persons): the group of the potential radiation risk with doses more than 150 mGy (33488 persons) and the group of the high radiation risk with doses more than 240 mGy (6054 persons).     

HIV infection in the Warsaw Clinic of Infectious Hepatology]

An epidemiological survey of patients in the Warsaw Clinic of Infectious Hepatology, the Polish National Center of AIDS Control, has been made. The epidemiological evaluation of risk groups and the age of HIV-infected persons has revealed that in Poland they are similar to those in Europe and in the USA (homosexuals and addicts aged 26-30 years). In 12% of the hospitalized patients the full clinical picture of AIDS, in 11.3% pre-AIDS (ARC) and in 58.1% lymphadenopathy (LAS) have been registered. In 18.4% of the patients only antibodies to HIV have been detected. The necessity of timely laboratory examinations for the determination of antibodies to HIV, whose presence may be signalled by any clinical symptom of the disease, has been shown.     

A strategy for research on psychological and social factors in hypertension

Stress-related research has thus far failed to provide an adequate understanding of hypertension and other psychosomatic ailments for three main reasons: First, there has been a continual failure to view stress as a relational phenomenon, that is, as a particular kind of transaction between person and environment. Second, there has been much confusion about the social, psychological and physiological levels of stress analysis; each is to some extent independent of the other, so that what happens at one level cannot stand for what happens at another. Third, the predominant research model has been structural and static. That is, the researcher looks at some environmental or personality characteristic, treating it as a stable property, and attempts to relate it to the risk of hypertension across persons or groups. Such an approach overlooks the key social, psychological and physiological mediating processes (e.g., social supports, cognitive appraisals, and coping) that are concurrent with and have causal significance in blood pressure elevation or change. Structural research models need to be supplemented with process-oriented ones in which the same persons are observed across various adaptational encounters and over time.     

Hereditary hemochromatosis: the clinical significance of the S65C mutation

Hereditary hemochromatosis (HH) is a common genetic disease with iron overload in certain organs, especially the liver. Most cases are homozygous for the C282Y mutation in the HFE gene; a few are C282Y heterozygous, compound C282Y/H63D heterozygous, or have no known mutation. A third mutation, S65C, has been associated with HH, but this finding is disputed. We have studied the clinical significance of various genotypes with the S65C mutation. In a population-based screening for HH in 65,238 persons, 613 had high serum transferrin saturation in two blood samples and were invited for HFE genotyping. In 556 persons with complete data sets, we studied the serum ferritin concentration and the risk of being diagnosed with phenotypic HH in the various genotypic groups. The phenotypic diagnosis was given without knowing the genotypic result. Except for the C282Y homozygotes, no differences in median serum ferritin concentrations were found between the various genotypic groups. However, the C282Y/S65C compound heterozygous group had a higher risk of being diagnosed with phenotypic HH than the wild-type group, as did the C282Y homozygous and the C282Y/H63D compound heterozygous groups. When combined with the C282Y mutation, the S65C mutation is associated with an increased risk of being diagnosed with phenotypic HH.     

DNA adducts in humans as dosimeters of exposure to environmental, occupational, or dietary genotoxins.

The quantitation of adducts of genotoxins with DNA is probably one of the best indicators of genetic damage due to exposure to toxins or carcinogens. It is generally believed that such adducts can lead to mutations, which in turn can trigger the initiation of the carcinogenic process. DNA adducts have been quantitated in white blood cells and in various tissues of smokers, persons in certain high-exposure occupations, and persons consuming foods contaminated with certain carcinogens. The feasibility of this approach for biochemical epidemiologic studies has been demonstrated using methods such as 32P-postlabeling, enzyme-linked immunosorbent assay, and synchronous fluorescence spectrophotometry. Relatively large interindividual differences in DNA adducts have been observed in both exposed and nonexposed persons. As a result, there are only a few studies in which clear quantitative and qualitative differences between these two groups have been observed. In addition, it appears that in some studies the 32P-postlabeling method does not detect the presence of the polycyclic aromatic hydrocarbon DNA adducts that are detectable by immunoassays. More extensive studies in additional populations at risk should shed further light on the utility of DNA adduct analysis in biochemical monitoring, especially if further refinements in methodology would result in increased sensitivity and specificity.     

An anonymous survey of the population for antibodies to the virus causing AIDS

The anonymous survey of the population for the presence of human immunodeficiency virus (HIV) carried out in Moscow in 1987 revealed 4 seropositive persons among 10, 117 persons subjected to examination. These 4 persons belonged to typical risk groups with respect to the acquired immunodeficiency syndrome (AIDS). The questioning of the persons coming for examination made it possible to find out that a large percentage of them really had a risk of contacting HIV infection; besides, a considerable proportion of the visitors proved to have signs of AIDS phobia.     

The reactogenicity and antigenic activity of a meningococcal group B vaccine made from a natural complex of the specific polysaccharide and outer membrane proteins

Group B meningococcal vaccine consisting of the natural complex of specific polysaccharide and outer membrane protein (OMP) has been shown to be moderately reactogenic, safe with respect to the effect of undermining tolerance to human brain tissue antigens and to produce no allergization of humans. The vaccine under study possesses antigenic activity: (a) immunization with this vaccine ensures the fourfold rise of the level of antibodies to the group-specific polysaccharide of group B meningococcus in about 80% of persons with the initially low level of antibodies, this percentage being retained during the whole period of observation, i. e. 85 days; (b) the vaccine enhances the level of antibodies to meningococcal OMP, determined in the enzyme immunoassay and the passive hemagglutination test; (c) these data are indicative of the expediency of immunizing the risk groups of persons with the initially low level of antibodies.     

Melanoma risk factors and atypical moles.

Despite important advances in the treatment of melanoma, the prognosis for advanced disease remains discouraging. This fact, in combination with a worldwide epidemic of melanoma among persons of white skin type, has focused attention on identifying melanoma in its early, surgically curable stages. Attention has also been directed toward pinpointing which persons are at increased risk for melanoma to reduce risk where possible and to aid early diagnosis. Essentially all epidemiologic studies have identified an increased number of melanocytic nevi as an important risk factor in the development of melanoma, but controversy has arisen concerning the risk associated with certain types of nevi, particularly "dysplastic" nevi. We review melanoma risk factors and examine the relationship between melanocytic nevi and melanoma to clarify for primary care physicians what is "known" (non-controversial) and what is "unknown" (controversial). We propose a working definition of an atypical mole phenotype and outline an approach to managing high-risk patients.     

The organization of the work to determine antibodies to the human immunodeficiency virus in the Republic of Byelarus

The study revealed that the method of mass screening for the detection of antibodies to HIV antigen, carried out in the Republic till 1993, proved to be economically and diagnostically unjustified. Starting from 1993, the work on the step-by-step reduction of groups to be tested for the presence of antibodies to HIV began. At the same time from 1997 the proportion of tested donors of blood, organs and tissues, as well as persons belonging to high risk groups, increased in comparison with 1993 (from 23.3% to 40% and from 5.3% to 21% respectively). Voluntary and anonymous testing for the presence of HIV infection was organized and legally introduced. In comparison with 1991, in 1997 the number of persons who voluntarily underwent testing increased 3.7 times. The period of transition from mass screening to selective one was noted to have no effect on the detection of HIV-infected persons. Since 1995 the method of "patrol" epidemiological surveillance was also used. 2,118 persons underwent testing, the results of screening were negative. During the period of 3 years the testing of 12,547 young people called up for military service revealed 28 seropositive persons in the region where an outbreak of HIV infection had been registered among addicts using drugs intravenously.     

Densitometric parameters in the presence of risk factors and complications of osteoporosis

The paper deals with the densitometric study of 3000 persons due to 21 to 85 years. It presents the major common risk factors of osteoporosis and osteopenia and the indices of bone mineral density in relation to age, risk factors, and a history of bone fractures. Groups of the examinees were formed according to the history and densitometric data. Based on the findings, the author has substantiated a methodological approach to using X-ray densitometry in the identified groups.     

Role of genetic factors in the epidemic process in respiratory viral infections

Observations carried out during 1973-1979 indicate that persons, who are frequently ill, determine the incidence of influenza and acute respiratory diseases among various groups of adult population at all epidemic periods. In constantly observed groups of different ages such persons were the source of 60-85% of the outbreaks of acute respiratory diseases. The correlation between genotypic blood markers (the ABO and HLA systems) and susceptibility to respiratory viruses has been established.     

Employment of persons with epilepsy and heart disease

Among persons who are often considered handicapped so far as employability is concerned are two groups deserving of special attention-persons with heart disease because of the ever-increasing number of them, and persons with epilepsy because of the extreme difficulty they have had in getting suitable jobs.A considerable number of persons with cardiac disease and a lesser number with epilepsy have been employed by the California Division of Lockheed Aircraft Corporation during the past ten years. It has been the experience there that the employment of such persons, once they are placed in jobs compatible with their physical limitations, has not resulted in unduly increasing the company's liability or labor cost and has not created operational problems of major proportions or jeopardized anyone's safety. Considerable research and effort are being expended by governmental and other agencies and associations to further enhance the safe placement of such persons. It is believed that these efforts, if coupled with realistic interpretation of the Workmen's Compensation Act in this regard, will bring about more liberal and widespread acceptance of persons with heart disease and epilepsy by industry.     

Chromosomal instability parameters in the population affected by nuclear explosions at the Semipalatinsk nuclear test site

A population genetic survey of 149 persons who were born and have permanently lived in the contaminated zones of the Semipalatinsk region has been performed. A cytogenetic study has demonstrated that the frequency of aberrant cells is 1.7-3 times higher than control parameters. The total frequencies of chromosome aberrations are 3.43 +/- 0.48, 3.1 +/- 0.3, 1.8 +/- 0.2, and 1.15 +/- 0.17 aberrations per 100 cells in the populations of the extreme radiation risk (ERR), maximum radiation risk (MaxRR), minimum radiation risk (MinRR), and control zones, respectively. The high chromosome aberration rate in all three zones of radiation risk has been detected mainly due to radiation-induced chromosome markers, including paired fragments (1.2 +/- 0.2, 0.94 +/- 0.13, and 0.43 +/- 0.06 per 100 cells, respectively), dicentric and ring chromosomes (0.44 +/- 0.04, 0.45 +/- 0.07, and 0.11 +/- 0.02 per 100 cells, respectively), and stable chromosome aberrations (0.74 +/- 0.16, 0.8 +/- 0.1, and 0.63 +/- 0.13 per 100 cells, respectively). The qualitative spectra of the cytogenetic lesions observed in these groups indicate a mutagenic effect of ionizing radiation on chromosomes in the populations studied.     

The information value of a questionnaire test in an epidemiologic survey

To find out persons with decreased immune responsiveness in organized groups, the inquiry test has been proposed. The test has proved to be highly informative. Besides, the possibility of using this method for the characterization of the effectiveness of epidemic control measures has been shown.     

Effectiveness of the seroprophylaxis of tick-borne encephalitis depending on the titer of homologous gamma-globulin antihemagglutinins

To give a rationale for using homologous gamma globulin with antihemagglutinin titers of 1 : 20 to 1 : 80 for the prophylaxis of tick-borne encephalitis, 5-year observations covering all persons attacked by ticks in one of the intensive natural foci of the disease in the Western Urals have been made. The threefold statistically significant difference in the morbidity rate of tick-borne encephalitis between groups of persons immunized and not immunized with gamma globulin has been shown.