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Biomedical subjects

R Martorell

Publications and source records attributed to R Martorell.

At least 55 records · Page 3Linked to original sources
PubMed1995

Nutritional supplementation during the preschool years influences body size and composition of Guatemalan adolescents.

Effects of supplementary feeding during early childhood on body size and composition at adolescence are examined in a population with marked growth failure in the first 3 y of life. The data came from a supplementation trial conducted in rural Guatemala from 1969 to 1977 and a 1988-89 follow-up study of the same subjects at adolescence. Two pairs of villages participated in the trial. One village from each pair received a high protein-energy supplement (Atole), which significantly improved dietary intakes, whereas the other village of the pair received a low-energy, no-protein supplement (Fresco), which did not impact appreciably on dietary intakes. Children from Atole villages grew better during the preschool period than children from Fresco villages. At adolescence, subjects from Atole villages were taller, weighed more and had greater fat-free masses than subjects from Fresco villages. Differences in height at adolescence were slightly reduced in magnitude relative to differences at 3 y of age. However, differences in weight were increased in adolescence relative to 3 y of age.

Adolescent↗
PubMed1995

Nutritional supplementation during the preschool years and physical work capacity in adolescent and young adult Guatemalans.

A follow-up study (1988-89) was carried out in 364 rural Guatemalans, 11-27 y of age, who earlier had participated in a nutritional supplementation experiment. Among its objectives was the assessment of the long-term effects of the nutrition intervention on physical work capacity. Subjects and their mothers from two villages had available a high-energy, high-protein supplement (Atole: 163 kcal/682 kJ and 6.4 g protein per serving or 180 mL), whereas in two other villages a low-energy, no-protein supplement (Fresco: 59 kcal/247 kJ per 180 mL) was provided. Consumption was ad libitum. Maximum oxygen consumption (VO2max) at follow-up was significantly greater in Atole compared with Fresco subjects of both sexes. In subjects 14-19 y, exposed to supplementation throughout gestation and the first 3 y of life, Atole males had a significantly higher VO2max (2.62 L/min) than Fresco males (2.24 L/min), the differences remaining significant even after controlling for body weight and fat-free mass; also, there was a significant positive relationship between amount of supplement consumed and VO2max. The supplementation effect in females of similar age was not statistically significant. It is concluded that early nutritional improvements can have long-lasting effects on physical performance.

Adolescent↗
PubMed1995

Age at menarche and nutritional supplementation.

Retrospective data on age at menarche were collected for 832 Guatemalans 15-30 y in age to test whether exposure to a high energy and high protein supplement (Atole: 163 kcals/682 kJ and 11.5 g protein per cup or 180 mL) during childhood led to earlier menarche than did exposure to a low energy, no protein supplement (Fresco: 59 kcals/247 kJ in 180 mL). Mean age at menarche was similar in Atole (13.75 +/- 1.22 y; mean +/- SD) and Fresco (13.74 +/- 1.36 y) groups. The corresponding value for immigrants (n = 144), subjects not exposed to the supplements, was 13.55 +/- 1.20 y. Year of birth as well as socioeconomic status (SES) were associated with age at menarche. Age at menarche declined by 0.69 y over the 15-y period and menarche occurred earlier in higher SES households. Significant positive interactions between supplement type and SES and between supplement type and year of birth were found, but plausible explanations for them could not be advanced.

Adolescent↗
PubMed1995

Early nutritional supplementation and skeletal maturation in Guatemalan adolescents.

The effect of early childhood nutritional supplementation on skeletal maturation at adolescence was investigated in 663 rural Guatemalans, aged 11-18 y. Skeletal maturation was assessed by the Tanner-Whitehouse-2 method. The subjects were former participants in the Institute of Nutrition of Central America and Panama longitudinal study of growth and development (1969-77) residing in four villages (two large and two small) in eastern Guatemala. The villages were randomized within pairs to receive either a high energy, high protein supplement (Atole) or a low energy supplement with no protein (Fresco). Skeletal maturity was observed across all villages to be delayed significantly relative to a British reference for boys < 14 y of age, but not for older boys or for girls < 14 y of age. Delays in girls > 14 years could not be determined reliably because many had reached maturity. Girls < 14 years from Atole villages were more advanced in skeletal maturity than similar age girls from Fresco villages but these differences were found only in comparisons of the large villages. The relationship between early nutrition and biological maturation at adolescence may be obscured in this sample by the advanced age at which the subjects were examined in adolescence.

Adolescent↗
PubMed1995

Nutrition in early life and the fulfillment of intellectual potential.

The effects of early supplementary feeding on cognition are investigated using data collected during two periods in four Guatemalan villages. The first was the Institute of Nutrition of Central America and Panama (INCAP) longitudinal study from 1969 to 1977 and the second was a cross-sectional follow-up of former participants carried out in 1988-1989. The principal objective of these studies was to assess the differential effect of two dietary supplements, Atole containing 163 kcal/682 kJ and 11.5 g protein per cup or 180 mL and Fresco containing 59 kcal/247 kJ and 0 g protein per cup, that were given to mothers, infants and young children. Performance was assessed on a battery of psychoeducational and information processing tests that were administered during adolescence. Consistent differences between groups were observed on psychoeducational tests. Subjects receiving Atole scored significantly higher on tests of knowledge, numeracy, reading and vocabulary than those given Fresco. Atole ingestion also was associated with faster reaction time in information processing tasks. In addition, there were significant interactions between type of dietary supplement and socioeconomic status (SES) of subjects. In Atole villages, there were no differences in performance between subjects in the lowest and highest SES categories. On the other hand, performance in Fresco villages was best in the highest compared with the lowest SES group. After close scrutiny of alternative hypotheses, it is concluded that dietary changes produced by supplementation provide the strongest explanation for the test performance differences observed in the follow-up between subjects exposed to Atole and those exposed to Fresco supplementation.

Adolescent↗
PubMed1995

Results and implications of the INCAP follow-up study.

This article is a critical synthesis of 12 papers included in this supplement. The set deals with the short- and long-term effects of improving nutrition in Guatemalan villages characterized by deficient diets, high rates of infection and pronounced growth retardation in the first 3 y of life. The data reviewed come from two studies carried out over two decades: the Institute of Nutrition of Central America and Panama (INCAP) longitudinal study (1966-1977) and its follow-up (1988-1989). The longitudinal study included a nutrition intervention that improved the energy and nutrient intakes of women and preschool children. Its effects included improved birthweights, reduced infant mortality rates and improved growth rates in children < 3 y of age. Growth rates from 3 to 7 y of age, similar to those of well-nourished children, were not affected by the intervention. The follow-up study was conducted when the subjects were 11-27 y old. Among the long-term effects found were greater stature and fat-free mass, particularly in females, improved work capacity in males and enhanced intellectual performance in both genders. The nutrition intervention did not, on the other hand, accelerate maturation during adolescence, as measured by skeletal age or age at menarche. It is concluded that improved nutrition in early childhood has important long-term effects in the adolescent and adult.

Adolescent↗
PubMed1994

Inhibition by anti-sperm monoclonal antibodies of the penetration of zona-free hamster oocytes by human spermatozoa.

Fourteen mAb specific for human sperm membrane antigens were selected to investigate their inhibitory effect on fertilization. The antigens were not expressed in other human somatic tissues but were present in sperm from other species. The antibodies were purified from ascites fluid produced in mice. The zona-free hamster egg penetration assay was used for the evaluation of the blocking ability of these antibodies. The inhibition rate was generally related to a decrease in the number of adherent sperm. Three groups of antibodies were distinguished: (i) four mAb that have high inhibition at any concentration; (ii) four mAb with an intermediate inhibitory effect, that is more dependent on the antibody concentration tested; and (iii) six mAb with little or no effect at any concentration. The presence of antibodies leads to a lower penetration index, or number of penetrating sperm per oocyte. MAb specific for head antigens promote high inhibition of fertilization; these antibodies show a patchy staining on the sperm head. The antibodies localized in the midpiece have an intermediate inhibitory effect. No inhibition is detected with the equatorial region binding pattern. Sperm agglutination does not play any role in the inhibition caused by the antibodies described here.

Animals↗
PubMed1994

Reversibility of stunting: epidemiological findings in children from developing countries.

The growth literature from developing countries is reviewed to assess the extent to which stunting, a phenomenon of early childhood, can be reversed in later childhood and adolescence. The potential for catch-up growth increases as maturation is delayed and the growth period is prolonged. However, maturational delays in developing countries are usually less than two years, only enough to compensate for a small fraction of the growth retardation of early childhood. Follow-up studies find that subjects who remain in the setting in which they became stunted experience little or no catch-up in growth later in life. Improvements in living conditions, as through food supplementation or through adoption, trigger catch-up growth but do so more effectively in the very young. One study cautions that in older adopted subjects, accelerated growth may accelerate maturation, shorten the growth period and lead to short adult stature.

Adolescent↗
PubMed1993

Early supplementary feeding and cognition: effects over two decades.

The study reported in this Monograph of the effects of early supplementary feeding on cognition included two data collection periods: a longitudinal investigation spanning the years 1969-1977 and a cross-sectional follow-up carried out in 1988-1989. The study was conducted in four rural villages in Guatemala and compared the differential effects of exposure in childhood (0-7 years) to an Atole supplement (11.5 g of protein; 163 kcal) or a Fresco supplement (59 kcal) on performance on a battery of psychoeducational and information-processing tests in adolescence and young adulthood (11-24 years). In this report, particular attention is given to a cohort of subjects who were exposed to the supplement prenatally and during at least the first 2 years of postnatal life. Data on this subsample are contrasted with those on a cohort of subjects who received the supplement only after 24 months of life. The Monograph also reports results from an analysis of the supplementation effects in infancy and early childhood. Consistent differences between groups on the psychoeducational tests were observed. Adolescents from Atole villages scored significantly higher on tests of knowledge, numeracy, reading, and vocabulary than Fresco subjects. Atole was also associated with a faster reaction time in information-processing tasks. Significant interactions helped identify two groups who benefited more from the Atole treatment: those at the lowest levels of socioeconomic status and those who attained the highest levels of primary schooling. The consistent differences in test performance established in the follow-up assessment contrast sharply with the few and less pronounced between-group differences observed in the infancy and preschool periods. After close scrutiny of alternative hypotheses, it is concluded that nutritional differences provide the strongest explanation for the test performance differences observed in the follow-up between the subjects exposed to the Atole and those exposed to the Fresco supplement.

Adolescent↗
PubMed1992

Predicting body composition from anthropometry and bioimpedance in marginally undernourished adolescents and young adults.

Body-composition prediction equations were developed using data from a sample of 201 female and male Guatemalan ladinos (ie, people of Amerindian-European descent) aged 11-25 y. Fat-free mass (FFM) values were estimated from body density by using the two-component model and age- and sex-specific values for the density of FFM. The root-mean-square error (RMSE) of the best model predicting FFM from a set of simple anthropometric variables was 1.59 kg for females and 1.90 kg for males. The addition of more extensive anthropometry to the set of candidate predictors reduced the RMSE to 1.42 kg for females and 1.88 kg for males. The subsequent addition of a bioelectrical impedance measure (Ht2/R) further reduced the RMSE to 1.32 kg for females and 1.82 kg for males. These results suggest that for a marginally undernourished population with relatively little body fat, simple anthropometrics are as useful as more sophisticated measures for the prediction of body composition.

Adolescent↗
PubMed1991

Selected measures of health status for Mexican-American, mainland Puerto Rican, and Cuban-American children.

The 1987 National Vital Statistics System and the Hispanic Health and Nutrition Examination Survey (1982 through 1984) were used to assess the health status of Mexican-American, mainland Puerto Rican, and Cuban-American children by examining the prevalences of pregnancy outcomes and chronic medical conditions. The low-birth-weight rate among Hispanics (7.0%) compared favorably with that of non-Hispanic whites (7.1%) despite the greater poverty and lower levels of education among Hispanics. When examined by Hispanic subgroup, however, significant differences were present, with mainland Puerto Ricans having the highest prevalences of low-birth-weight infants. Premature births were more common among all three Hispanic subgroups than among non-Hispanic whites. Mexican-American and Cuban-American children had a similar prevalence of (3.9% and 2.5%, respectively) chronic medical conditions compared with non-Hispanic white children; Puerto Rican children had a higher prevalence of chronic medical conditions (6.2%). When assessed by these health status indicators, Hispanic children seem to have a health status similar to non-Hispanic white children. However, mainland Puerto Rican children seem at greater risk for poor health, reflecting the US Hispanic population's heterogeneity. Health programs targeted at US Hispanics should appropriately consider these group differences.

Adolescent↗
PubMed1991

Prevalence of overweight and obesity in US Hispanic populations.

Previous studies showed that Hispanics have higher levels of overweight and obesity than do US whites. The Hispanic Health and Nutritional Examination Survey (1982-1984) provides the basis for examining the physical characteristics of this population on a wider scale than previously possible. Data for body mass index (BMI; weight/height2) and triceps and subscapular skinfold thicknesses were examined for the 7052 Mexican Americans, 1307 Cubans, and 2690 Puerto Ricans for whom each of these measurements were available. Prevalence of obesity and overweight was defined as BMI in excess of the 95th and 85th percentiles, respectively, of US reference standards. In male adults prevalence values were, respectively, 10.6% and 33.5% for Mexican Americans, 9.6% and 31.3% for Puerto Ricans, and 9.0% and 34.0% for Cubans. In female adults prevalence values were, respectively, 15.1% and 42.3% for Mexican Americans, 7.8% and 40.7% for Puerto Ricans, and 15.0% and 38.2% for Cubans. Skinfold-thickness data for these populations indicate a centralized distribution of adipose tissue, especially in males, and increased subscapular skinfold thicknesses in older women.

Acculturation↗
PubMed1991

The estimated cost of treating unmet dental restorative needs of Mexican-American children from Southwestern US HHANES, 1982-83.

The dental restorative treatment needs of Mexican-American children, aged 1-17 years, were assessed from the 1982-83 Southwestern US Hispanic Health and Nutrition Examination Survey (HHANES). This report analyzed those needs and applied a dollar cost to them, using 1982 median fees of US general practitioners. The total estimated cost required to meet those needs for the population estimate of 3,396,770 children was $236,856,772 (95% CI: $198,575,174 to $275,138,370). The mean cost per child was $69.73 (SE: 5.75). Although a majority of the children had no unmet need, 15-, 16-, and 17-year-olds had extensive needs for crowns, endodontics, and prosthetic replacement of teeth, with accompanying high costs: mean total cost per examinee was $177 (SE: 28.97), $161 (SE: 32.20), and $237 (SE: 33.26), respectively. The treatment needs were compared with the previously published regional data from the 1979-80 NIDR survey, which used the same dental restorative treatment needs (DRTN) index. The findings indicated a great need for dental treatment among Mexican-American children that appeared to exceed that of the general school-aged population. Our analysis, in providing estimates of the cost of needed treatment, might be useful in planning dental treatment programs and in comparing surveys.

Adolescent↗
PubMed1990

Maternal and fetal responses to the stresses of lactation concurrent with pregnancy and of short recuperative intervals.

In many regions of the world, women breastfeed one child while pregnant with the next. Among rural Guatemalan women participating in a nutrition-supplementation trial, lactation overlapped with pregnancy in 253 of 504 (50.2%) of the pregnancies. For cases where overlap occurred, 41.4% continued to breast-feed into the second trimester and 3.2%, in the third trimester. The maternal and fetal responses to the energetic stresses of overlap and of the duration of the recuperative (nonpregnant, nonlactating) interval were assessed. Overlap resulted in increased supplement intake. Short recuperative periods (less than 6 mo) resulted in increased supplement intake and reduced maternal fat stores. The energetic stresses of overlap and short recuperative periods did not significantly affect fetal growth. The mother appears to buffer the energetic stress, protecting fetal growth. This research demonstrates that evidence of depletion of maternal nutrient stores caused by a demanding reproductive history is found when reproductive stress is characterized adequately.

Anthropometry↗
PubMed1990

Consequences for maternal nutrition of reproductive stress across consecutive pregnancies.

Frequent cycles of reproduction increase the risk that lactation will overlap with pregnancy and shorten the duration of the recuperative interval (nonpregnant and nonlactating portion) within the reproductive cycle, thereby increasing the risk of maternal nutritional depletion. Nutritional responses to these stresses have been demonstrated by contrasting groups of women with different experiences; however, these relationships may be spurious and the result of third factors. In this study, responses to changing stress over consecutive pregnancies were studied and contrasted within individual Guatemalan women; biases caused by factors constant to women were eliminated. Stress was assessed by examining responses in maternal supplement intake, maternal fat stores, and birth weight. Overlap and short recuperative intervals were found to be stressful (in that order) for mothers as shown by increased supplement intake and reduced fat stores. Birth weight in term gestations was not affected, indicating that fetal growth is being protected at the cost of maternal nutritional status.

Adipose Tissue↗