Blood pressure in four remote populations in the INTERSALT Study.

Four remote population samples (Yanomamo and Xingu Indians of Brazil and rural populations in Kenya and Papua New Guinea) had the lowest average blood pressures among all 52 populations studied in INTERSALT, an international cooperative investigation of electrolytes and blood pressure. Average systolic blood pressure was 103 versus 120 mm Hg in the remaining INTERSALT centers; diastolic blood pressure in these four population samples averaged 63 versus 74 mm Hg in the 48 other centers. There was little or no upward slope of blood pressure with age; hypertension was present in only 5% of the rural Kenyan sample and virtually absent in the other three centers. Also in marked contrast with the rest of the centers was level of daily salt intake, as estimated by 24-hour urinary sodium excretion. Median salt intake ranged from under 1 g to 3 g daily versus more than 9 g in the rest of INTERSALT populations. Average body weight was also low in these four centers, with no or low average alcohol intake, again unlike the other centers. The association within these four centers between the above variables and blood pressure was low, possibly reflecting their limited variability. While several other INTERSALT centers also had low average body weight or low prevalence of alcohol drinking, when this was accompanied by much higher salt intake (7-12 g salt or 120-210 mmol sodium daily), hypertension prevalence ranged from 8% to 19%. These findings confirm previous reports that in populations with a low salt intake, there is little or no hypertension or rise of blood pressure with age.(ABSTRACT TRUNCATED AT 250 WORDS)

Observations of the Alto Xingu Indians (central Brazil) with special reference to nutritional evaluation in children.

Little information concerning the nutritional status of Brazilian Indians living primitively in a large area of the Amazon region is available at present. This study took place in the Xingu National Park, created to preserve the Indian population living in this area, along with its culture. Field work was done in three consecutive years (1974, 1975, 1976). At the end of this period 175 children had been studied (97 male and 78 female) all estimated to be under 5 yr of age. Two kinds of studies were performed: 1) cross-sectional: studying the children that entered in the nutritional survey every year, and 2) longitudinal: studying the children that were under observation for 2 or 3 consecutive yr. The nutritional status was evaluated by two age-independent anthropometric indices, namely, weight-for-height and arm-circumference-for-height. The weight-for-height index showed that 96.0% of the children examined were classified as well nourished, 3.4% suffered of 1st degree malnutrition and 0.6% of 2nd degree malnutrition. The arm-circumference-for-height revealed that 97.1% were well nourished and 2.9% were classified as suffering of a mild degree of malnutrition. Since both indices used can give normal results in a population in which there is severe stunting or nutritional dwarfism, a longitudinal study was drawn. Growth in height was studied, resulting normal in 84.8% of the measurements taken. In contrast to children from low income families living in the outskirts of large urban centers where malnutrition reaches 54.0%, the Indians remain as healthy as they were when last examined 30 yr ago.

Interaction between macrophage and parasite cells in lobomycosis. The thickened cell wall of Paracoccidioides loboi exhibits apertures to the extracellular milieu.

Lesioned, cutaneous, tissue fragments from five indians of the Caiabi tribe with lobomycosis, living in the Xingu National Park (Central Brazil), are analyzed by light and electron microscopy. Clusters of macrophages filled with parasite and/or cell wall debris, separated by collagen fiber bundles, characterize the morphological pattern seen in thick and thin sections. Paracoccidioides loboi within the phagocytic cells are multinucleate organisms whose cytoplasm contains mitochondria with few cristae, ribosomes and vacuoles; a large, dense, globular body and peculiarly curved mitochondrial profiles are described. From the outer portion of the double layered parasite cell wall, radial projections commonly emerge, rendering the structure conspicuously thicker and more irregularly surfaced than that seen in many other phagocytized yeast cell species. The cell wall layers from fungi possessing distinct subcellular organization show a weak or no reaction for acid phosphatase. Most of the foamy cells commonly seen by light microscopy are macrophages filled with fungal cell wall remnants which exhibit marked acid phosphatase activity. Occasionally, microchannels extending from the outer layer of the parasite cell wall to the macrophage surface and exocytic-like openings, possibly derived from the fusion of the macrophage membrane covering the parasite cell wall and the macrophage plasmalemma can be seen. Through such routes, material of texture and density similar to that of the outermost cell wall layer appears to be deposited extracellularly.

Lanthanum nitrate labelling of the outer cell wall surface of phagocytized Paracoccidioides loboi in human lobomycosis.

Lesioned skin tissues from a female Caiabi indian with lobomycosis were processed for routine electron microscopy using, in the initial steps, solutions containing 2% lanthanum nitrate. The pattern of tracer distribution suggests that the tracer penetrates into the cavity containing the parasite through exocytotic-like apertures situated at the cell wall outer region. The tracer also infiltrates the virtual space between the cell wall and its recovering membrane, spreading over varying areas of the outer surface of the cell wall. The contrast imparted to the pericellular macrophage space by the lanthanum nitrate enabled easy localization of fibrillar, cell wall derived material which reaches the adjacent extracellular milieu.

[Prevalence of serologic markers of hepatitis B and D viruses in children of the Caiabi and Txucarramãe tribes from the Indian Reservation of Xingu, central Brazil]. / Prevalência dos marcadores sorológicos dos vírus da hepatite B e D em crianças das tribos Caiabi e Txucarramãe do Parque Indígena do Xingu, Brasil central.

The medical literature has shown that the inhabitants of the Amazon region are highly affected by hepatitis B and delta viruses infection, but this has never been studied in Indian children by age group. A study of the prevalence of serological markers of hepatitis B and delta viruses in Indian children aged 0 to 14 years living in the PIX was carried out. This Park is located in Central Brazil, a region which is in the transition between the savannab to the south and the Amazon jungle to the north. To determine the prevalence of HBV and HDV markers in Indian children and to characterize the route of HBV transmission in this region. Out of the 17 tribes living in the PIX, two--the Caiabi and the Txucarramãe--were chosen because both live in the North part of the Park, but have quite different ways of life. The overall prevalence of HBV serum markers was: HBsAg, 4.5%; anti-HBs, 39.6%; anti-HBc, 44.1%; any marker of HBV, 47.3%; and anti-HDV, 0.0%. However, a striking difference in the prevalence of hepatitis B markers was observed between the two tribes: younger Caiabi children were much less affected than the Txucarramãe ones. The prevalence of HBsAg in fertile women was 12%, being anti-HBe positive. Our data suggest that HBV infection is highly prevalent among Indian children living in this Indigenous Park and vertical infection is not an important route of transmission in either tribes.

[Health and disease among Panará (Kreen-Akarôre) Indians in Central Brazil after twenty-five years of contact with our world, with an emphasis on tuberculosis]. / Saúde e doença em índios Panará (Kreen-Akarôre) após vinte e cinco anos de contato com o nosso mundo, com ênfase na ocorrência de tuberculose (Brasil Central).

The Panará, who had previously lived in isolation from Brazilian national society in the Amazon forest, were first contacted in 1973. Two years later they were moved to another area in Central Brazil. During this same period they were reduced to 82 members, the survivors of a population of 400 to 500 in the mid-1960s. In 1995 they returned to a small area in their old territory still not occupied by outsiders. There, three years later, a health survey showed a presumed diagnosis of tuberculosis in 15 individuals out of a population of 181. Further tests in the town of Colider, based on clinical data and chest X-rays, confirmed the diagnosis in 10 Panará (6 children under 10 years of age and 4 adults from 40 to 50 years old). BCG scars were present in the entire population. The nutritional status of Panará children was better than that of other indigenous groups in the Amazon region. The following measures were introduced for Tb control: a) treatment follow-up in the village, under direct supervision by both a nurse and the local indigenous health worker; b) compliance with defined criteria for ending treatment; c) periodic control of contacts and non-contacts; c) and establishment of a reference system with the health services in Colider.

Measles vaccine coverage and immune response in children of Caiabi and Metuktire Indian tribes living in malarial endemic area: Parque indígena do Xingu, Central Brazil.

Measles vaccination efficiency was evaluated in children from two Indian tribes - Caiabi and Metuktire - living in the Amazon region, in the Parque Indigena do Xingu (PIX). The population sample, selected at random, made up 37 Caiabi and 28 Metuktire children, aged from 20-75 months (40%). For operational and epidemiological reasons, measles vaccine is given from 6 months of age. The average age of children when they received the vaccine was 11.5 months for the first dose and 20 months for the second. The search for IgG antibodies against measles virus and Plasmodium falciparum was made through immunofluorescence assay (IFA). Measles vaccine coverage has reached 60% at 12 months of age and 92% at 18 months, whereas post-vaccine serum conversion was 95% in Caiabi children (geometric mean of titres (GMT) 126) and 89% in Metuktire (GMT 109). The difference in GMT is not statistically significant. Seventy-three per cent of Caiabi children (GMT 101) and 100% of Metuktire children (GMT135) were plasmodium antibody positive, showing they had been exposed to malarial infection. Despite the differences detected, the immune response to measles vaccine was satisfactory in both groups, with a positive percentage consistent with that achieved in non-malarial areas in Americas. The results show the efficiency of a vaccination programme in an indigenous area despite the difficulties in reaching the villages and maintaining the cold chain, and also despite the malaria endemicity.

Cardiovascular risk factors among Brazilian Karib indigenous peoples: Upper Xingu, Central Brazil, 2000-3.

BACKGROUND: Brazil has more than 200 indigenous peoples with 170 different languages that result in different epidemiological and demographic situations. The objective of this study was to describe the nutritional and metabolic profile of the adult Karib indigenous peoples, inhabitants of the Upper Xingu region, as well as to evaluate their possible effects on their cardiovascular health. METHODS: In 2002, the Karib population comprised 1091 individuals, 390 of whom (35.7%) were 20 years of age or older. This study was based on results from 251 adult individuals (64.4%). chi(2) statistics were used to evaluate the possible relationship between chronic diseases and tribe, gender and age. Analysis of variance was used to compare the average values of the biomedical variables of the individuals according to tribe and gender. RESULTS: The prevalence of the main risk factors detected was: 39.3% overweight and 6.8% obese, mainly among men (60.4%), 41.8% for central obesity mainly among women (66.7%), 68% for dyslipidaemia and 15.4% for blood pressure alterations mainly among men (24.7%). Overall, percentages were higher than in the non-indigenous Brazilian population. The percentage of individuals presenting simultaneously with at least two cardiovascular risk factors (29%) was also remarkable. CONCLUSIONS: These findings emphasize the need to implement preventive health measures to control obesity and other cardiovascular risk factors in indigenous peoples.

Male pubertal seclusion and risk of death in Indians from Alto Xingu, central Brazil.

Male pubertal seclusion is a cultural characteristic shared by 10 Indian tribes in Alto Xingu, central Brazil. The seclusion lasts from several months to three years, with periods of interruption. Seclusion acts as a rite of passage and is connected with a boy's social, psychological, and physical maturation process into adulthood. This period is marked by many rules and taboos, and boys are considered highly vulnerable to the workings of evil entities. From 1978 to 1985, 133 boys between the ages of 11 and 20 years were observed in seclusion. Twenty-four of these youths showed clinical symptoms of intoxication, with seven of them dying in the acute phase, whereas the other seventeen developed peripheral neuropathy. The mortality rate among males was 6.6 times higher than that among females. Our findings suggest that the high risk of death associated with male pubertal seclusion results from the use of some native plants in infusions or ointments in the rite's purification process.