Showing papers by "World Health Organization published in 1986"

AIDS in Africa: an epidemiologic paradigm

Abstract: Cases of the acquired immune deficiency syndrome (AIDS) have been reported in countries throughout the world. Initial surveillance studies in Central Africa suggest an annual incidence of AIDS of 550 to 1000 cases per million adults. The male to female ratio of cases is 1:1, with age- and sex-specific rates greater in females less than 30 years of age and greater in males over age 40. Clinically, AIDS in Africans is often characterized by a diarrhea-wasting syndrome, opportunistic infections, such as tuberculosis, cryptococcosis, and cryptosporidiosis, or disseminated Kaposi's sarcoma. From 1 to 18% of healthy blood donors and pregnant women and as many as 27 to 88% of female prostitutes have antibodies to human immunodeficiency virus (HIV). The present annual incidence of infection is approximately 0.75% among the general population of Central and East Africa. The disease is transmitted predominantly by heterosexual activity, parenteral exposure to blood transfusions and unsterilized needles, and perinatally from infected mothers to their newborns, and will continue to spread rapidly where economic and cultural factors favor these modes of transmission. Prevention and control of HIV infection through educational programs and blood bank screening should be an immediate public health priority for all African countries.

Four generations of probable person-to-person transmission of human monkeypox

Abstract: This paper examines an outbreak of five cases of human monkeypox which occurred in children belonging to two families living in the West Kasai region of Zaire during May-July 1983. Epidemiologic investigations suggest that the first case was infected from an animal source, possibly a monkey, and that each of the other four cases was infected from a previous human case. Three of these cases of presumed person-to-person transmission occurred in close household contacts. The other case infection occurred either by casual contact within the hospital compound, or possibly because of infection due to use of the same syringe for injections. Human monkeypox is the most important orthopoxvirus infection in the post-smallpox eradication period. The disease is a zoonosis and person-to-person transmission is rather difficult. Thus, this episode is a rare event and special analysis of the circumstances is discussed. However, it supports the necessity to carry out surveillance and research on this disease as recently reported by Arita et al.

Cloned cell lines from a transplantable islet cell tumor are heterogeneous and express cholecystokinin in addition to islet hormones.

Abstract: A liver metastasis (MSL) with a remarkable in vitro proliferation potential has been identified in an NEDH rat carrying a transplantable x-ray-induced islet cell tumor. Two insulin-secreting cell lines, MSL-G and MSL-H, with doubling times of 3-5 d were established by repeated limiting dilution cloning. In vivo inoculation of MSL-G cells induced severe hypoglycemia caused by a small but highly heterogeneous tumor as revealed by immunocytochemistry. Whereas most cells stained for the islet hormones, insulin, glucagon, and somatostatin, clustered cells were discovered to contain cholecystokinin (CCK). Additional in vitro-limiting dilution cloning, followed by immunocytochemical characterization, clearly demonstrated the capacity of single cell clones to simultaneously express the same four hormones. Radioimmunoassays with a panel of site-specific antisera of culture supernatants and purified cell extracts showed the MSL-G2 cells to produce, store, and secrete readily detectable amounts of processed and unprocessed CCK. Gastrin was not detected while coexpression of glucagon and CCK were demonstrated. Mutant clones selected for resistance to 6-thioguanine (frequency, 2 X 10(-7] and checked for HAT (hypoxanthine, aminopterin, thymidine) sensitivity retained the capacity for multi-hormone expression. We propose that the MSL tumor contains pluripotent endocrine stem cells. The MSL tumor and the MSL-G2 cells in particular will allow studies of not only CCK biosynthesis and processing but also of mechanisms involved in tumor and islet cell differentiation.

The effect of doxycycline in infertile couples with male accessory gland infection: a double blind prospective study.

Abstract: Male accessory gland infection (MAGI, epididymo-prostato-vesiculitis) with abnormal semen quality was rarely the only abnormality in infertile couples since it occurred in no more than 1.6% of 2871 couples evaluated in 7 centres during a 3-year period. Both partners of 33 infertile couples with no other demonstrable abnormality than abnormal semen and MAGI consented to participate in a double blind trial and were treated with either doxycycline, 100 mg/day for 1 month (20 couples) or placebo (13 couples). Follow-up during a total of 175 couple-months included semen analysis and the recording of pregnancy. Pregnancy occurred in 2 of the doxycycline-treated couples (10%) and in 1 of the placebo treated couples (8%), corresponding with conception rates per month of 1.9% and 1.5%, respectively. Sperm motility and, to a lesser extent, morphology showed improvement in both groups. Evidence of infection, namely increased numbers of white blood cells and positive sperm culture, disappeared in both the doxycycline-treated and placebo group. It is concluded that features of MAGI in semen may regress spontaneously and are not influenced by the doxycycline treatment. The concomitant improvement of sperm motility and morphology still does not seem to enhance the probability of conception.

Life-table methods for contraceptive research.

Abstract: Life-table methods used for the analysis and interpretation of contraceptive follow-up studies differ from those used in other areas of medical research. The historical development of these methods in the contraceptive literature is outlined and the two main methods are discussed, compared and shown to differ mainly in their nomenclature; their results are very similar in practice. The daily life-table method is simpler to apply and interpret, and facilitates analysis using the logrank statistic as well as powerful regression modelling techniques for survival data.

Impact of population density on immunization programmes

Abstract: The eradication of smallpox was achieved by surveillance and containment vaccination after the failure of mass immunization campaigns. The reasons for this failure are considered in this paper. Comparison of population densities in the Indian subcontinent and Africa show that in highly populated areas even an 80% vaccine coverage will still leave a density of susceptibles high enough to maintain the disease, a finding with important implications for other vaccine campaigns.

Testicular volume, semen profile and serum hormone levels in fertile Thai males

Abstract: The fertility profile of 307 Thai male volunteers whose wives were currently in early pregnancy was established by genital examination, semen analysis and serum hormone analysis. Ninety percent of the subjects had testicular volumes of 12-25 ml (mean 17.2 ml) which was found to relate to body weight, height and the ponderal index as well as to the sperm count. However, values for semen analysis were significantly below the recognised standard for Caucasian males. There was an inverse relationship between testicular volume and the serum concentration of FSH, LH and prolactin. It is suggested that a common protocol for male fertility assessment should be used to establish standard parameters for racially different male populations.

Global and Regional Mortality Patterns by Cause of Death in 1980

Abstract: The authors estimate mortality by major cause for various regions of the world in 1980. "The World Health Organizations mortality data bank has been employed to derive the rates for the developed areas in the world whereas for the developing areas cause-specific mortality has been estimated on the basis of total mortality using a linear regression method." The estimates indicate that "infectious and parasitic diseases claim one third of all deaths in the world. Although diseases of the circulatory system and neoplasms are the two most common causes of death in the developed countries more than 50% of all deaths in the world due to these causes occur in the developing world. Mortality due to injury and poisoning is--contrary to that due to the other main causes of death--almost independent of the level of development of the area." (EXCERPT)

Depot-medroxyprogesterone acetate (DMPA) and cancer: memorandum from a WHO meeting.

Abstract: This memorandum from a World Health Organization (WHO) meeting held in 1985 summarizes available epidemiologic data from human studies including the WHO Collaborative Study of Neoplasia and Steroid Contraceptives on the association between depot-medroxyprogesterone acetate (DMPA) use and neoplasia. The WHO Collaborative Study is collecting data on cases and controls from 14 collaborating centers in 11 countries. Analysis of preliminary findings regarding cancers of the endometrium ovary liver and breast suggest that there is no increased risk in DMPA users. The relative risk estimates for these sites are 0.3 for endometrial cancer 0.7 for ovarian cancer 1.0 for liver cancer and 1.0 for breast cancer. The issue of a causal association between DMPA use and cervical cancer is less clear. The adjusted relative risk for cervical cancer was a nonsignificant 1.2; however somewhat higher risks were noted in subgroups of longterm (over 4 years) users. Although the WHO study is the 1st to provide reliable data on DMPA and neoplasia its findings must be regarded as tentative. At this point the data are insufficient to assess the influence of DMPA on risk among longterm users or risk long after initial exposure.

Glucose tolerance in Polynesia. Population-based surveys in Rarotonga and Niue.

Abstract: Glucose tolerance and the prevalence of impaired glucose tolerance (IGT) and diabetes in the Polynesian populations of Rarotonga and Niue were studied in 1980. Both Rarotongans and Niueans have been considerably influenced by sociocultural modernization and (in the case of Rarotonga) tourism. In both populations, the prevalence of abnormal glucose tolerance exceeded 10% in men and 15% in women. There was an association between glucose tolerance and age and obesity in both sexes, but not between glucose tolerance and physical activity. Glucose tolerance did not differ between Rarotongans and Niueans after allowing for differences in age and obesity. Comparisons between normal subjects, those with impaired glucose tolerance (IGT) and diabetic subjects with respect to factors that are traditionally associated with glucose intolerance provided some support for IGT as a truly intermediate diagnostic category of glucose tolerance.

Needs and implementation of preventive dentistry in China.

Abstract: Based on a literature review and recent surveys, the needs and implementation of preventive dentistry in China have been estimated. The average DMFT of 12- and 15-yr-old schoolchildren in Beijing were 1.61 and 2.11 respectively. The caries prevalence was higher in the coastal cities in the south. The caries rate was also higher in urban areas than in rural areas. There were some controversies in the results of fluoridation studies with one study reporting as high as 47.2% of the children to be afflicted with enamel fluorosis. The community periodontal disease status and treatment needs index (CPTNI) showed that 93% of the 12-yr-olds had bleeding, 98% had calculus and 15% had shallow pockets, with 100% of the children needing prophylaxis. There was a high prevalence of dental malocclusion with 54% of schoolchildren with dental anomalies, of whom 36% needed treatment. Much emphasis had been placed on oral pathology, oral medicine and maxillofacial surgery in the curriculum of Stomatology in Chinese dental schools.

Cytotoxic effects of four types of welding fumes on macrophages in vitro: a comparative study.

Abstract: The effects of fume particles given off by the manual metal arc (MMA) and metal inert gas (MIG) welding of stainless steel (SS) and mild steel (MS) were studied on rat alveolar macrophage cultures in vitro. The fumes were generated by welding, and particulate material obtained was collected on membrane filters. The macrophage cultures were exposed to the total dust and to its water-insoluble fractions. Cell variability and the release of both lactate dehydrogenase and one lysosomal enzyme from the cells to the medium were measured after an exposure period of 24 h. The cytotoxic control dust was DQ 12 quartz, and the inert control dust was pure titanium dioxide. According to the parameters studied, SS/MMA and MS/MMA welding fumes were cytotoxic to rat alveolar macrophages. The cytotoxic effect of SS/MMA welding fumes decreased after the samples had been washed with phosphate-buffered salt solution. The MIG welding fumes of SS and MS had markedly smaller effects on the cells. Diluted solutions of potassium chromate were also tested in order to investigate its role in the cytotoxicity of SS/MMA welding fumes. The results suggest that hexavalent chromium may be responsible for the cytotoxicity of SS/MMA.

The Tasmanian Insulin-treated Diabetes Register. Inception and progress in the first 12 months.

Abstract: A Statewide register of insulin-treated diabetic patients has been established in Tasmania. The register is the first of its kind in Australasia. Insulin treatment was chosen as the criterion for admission to the register because it was a suitably "hard" end-point, and because the completeness of the register could be validated easily by insulin prescription statistics. Both subjects with insulin-dependent diabetes mellitus and those with non-insulin-dependent diabetes mellitus (who happened to be treated with insulin as of the prevalence date, May l, 1984) are eligible for registration in the prevalent population. Furthermore, no age restrictions have been placed upon entry. It is to be hoped that this all-inclusive policy will assist in the development of an epidemiological definition of insulin-dependent diabetes mellitus. Access to cases has been by hospital records, general practitioners, lay bodies and general publicity. Of over 600 diabetic subjects who were contacted during the first 12 months of the study (approximately one-half of the estimated prevalent population), only three declined to join the register. Once fully established and validated, the register will be used to test aetiological hypotheses in addition to providing descriptive cross-sectional information about diabetes in Tasmania. It is intended that a longitudinal study of insulin-treated diabetes will follow once the cross-sectional information is complete.

Conceptual and measurement issues in assessing disability cross-nationally: Analysis of a WHO-sponsored survey of the disablement process in Indonesia.

Abstract: The World Health Organization, in collaboration with the Indonesian Institute of Health Research and Development, conducted a survey of disability in 14 of 24 Indonesian provinces. This survey was designed to assess the validity of the disablement process as described in WHO's (1980) classification of impairments, disabilities, and handicaps. We analyzed these data with a multivariate procedure which simultaneously identifies subgroups in the surveyed population and the typical attributes of those subgroups. The purpose of the analysis was to (a) determine the association of basic patterns of physical and psychological impairments with disabilities (limitations of the ability to perform certain functions) and handicaps (limitations in the ability to fulfill social roles); (b) assess how those disabilities and handicaps were expressed in urban and rural contexts in a developing country, and (c) determine how the relation of impairments with disabilities and handicaps varied with age.