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Leishmania braziliensis, growing axenically at 26 C and transferred to 34 C, changes within 3 hr from the long slender motile promastigote form to an ellipsoidal form with a nonmotile flagellum. This transformation is reversible for heat treatments of up to 12 hr. In this study we show by light microscopic measurements that the cells decrease in length and increase in diameter at constant volume. Quantitative morphometry of electron micrographs further demonstrates that: the distance between nucleus and kinetoplast decreases; the kinetoplast enlarges slightly; the distance between adjacent subpellicular microtubules decreases; and that after 3 hr of heat treatment there is no change in mitochondrial morphology, but after 6 hr of heat treatment the mitochondria lose their cristae and no longer possess a clearly defined double membrane. These observations are compared with the morphological changes that occur normally in the gut of a sandfly and in the in vivo transformation occurring during infection of the mammalian host and of macrophage cultures.

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The physical growth of middle to upper class children of primarily European ancestry attending the private French School in L Paz, Bolivia is described and analyzed to determine how high altitude affects growth in this group of children. The sample consists of 323 children, most between the ages of 8 and 14, who reside at altitudes between 3200 and 3600 meters, but who have spent different amounts of time at high altitude. Comparisons between children who differ in their exposure to high altitude, and comparisons between French School children and other samples of high and low altitude children were used to assess the effect of high altitude on growth. Children who had lived all their lives at high altitude were found to be smaller in terms of general body size than those who had spent the shortest amount of time at high altitude, confirming the results of previous investigations of child growth in the Andes. Most studies of indigenous Andean populations have found that chest dimensions relative to stature increase with altitude, but it is not clear that this same trend exists in Bolivian French School children. Although exposure to high altitude does affect the growth of French School children, their height is essentially the same as that of Guatemalan children of high socioeconomic status. Within the age range studied, the effect of high altitude is small relative to that of other environmental factors and genetic factors, even in these children of high socioeconomic status.

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PIP: The relationship between fertility and child mortality in the rural canton of Ancoraimes, Bolivia, a high-altitude Aymara Indian community located 135 km from La Paz, is analyzed in this article. 149 families with school-age children were interviewed; the data do not represent a random sample of the population. Among all 149 families, 6.30 live births and 4.85 living children were reported, while in 48 families with wife aged over 45 years, 7.5 liveborn children and 5.37 living children were reported. The number of reported deaths under age 1/1000 live births was 129 for all families and 114 for completed families, under age 2 there were 210 and 222 deaths/1000 live births, and under age 12 there were 228 and 242 deaths/1000 live births. The sex ratio at birth was 106. The infant mortality rate was calculated at 129/1000 live births. The similarity of the completed fertility level and infant mortality rate to those of other high altitude Andean communities suggests that the figures are not greatly underestimated. For the total sample, a significant positive correlation was found between fertility and childhood mortality, due mainly to the lower mortality of families with fewer than 5 live births. For the completed families, there was no correlation between fertility and childhood mortality. The probability of dying before age 12 was found to be greatest for 1st and 2nd births and to decrease with increasing birth order. When the probability of dying before age 12 was calculated for each birth order for each family size, there did not seem to be any systematic increase in the mortality rate at a given birth order for families with 5-13 live births.^ieng

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This study describes the growth characteristics of Aymara children living in Ancoraimes, Bolivia at altitudes between 3800 and 4000 meters. Anthropometric measurements were made on 510 children between the ages of 6.0 and 20.9 years, 360 males and 150 females. The growth pattern of Ancoraimes Aymara children is very similar to that of other high altitude Andean populations. They are greatly delayed in height and weight, exhibit little sexual dimorphism in body size and, relative to stature, have larger chest dimensions than U.S. children. Compared to Quechua children living at higher altitudes in Peru, Ancoraimes children tend to be taller and heavier but have significantly smaller chest dimensions. Although the causes of the size differences between these two groups are not entirely clear, they may be due to the different altitudes at which the groups reside.

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PIP: The author attempts an evaluation of the significance of children's economic input using child growth as an indirect indicator of the economic value of children. Children in households of varying size and age composition are compared on the basis of five anthropometric measurements. Data are for 510 children from a community of Aymara Indians living in Ancoraimes county, Bolivia^ieng

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