Search PubMed⌕ Search

Biomedical subjects

B Lozoff

Publications and source records attributed to B Lozoff.

52 records · Page 3Linked to original sources

The effects of short-term oral iron therapy on developmental deficits in iron-deficient anemic infants.

To assess the effects of iron therapy on developmental test scores in infants with iron deficiency anemia, 68 Guatemalan babies 6 to 24 months of age, with and without mild iron deficiency anemia, were tested with the Bayley Scales of Infant Development before and after one week of oral iron treatment. The two major findings of the study were developmental deficits in the anemic group prior to treatment, and lack of rapid improvement with short-term oral iron therapy. The mean pretreatment Mental Development Index of the anemic group was significantly lower than that of nonanemic infants. The anemic group's pretreatment Psychomotor Development Index was also lower than that of the nonanemic control group. In a double-blind randomized study, six to eight days of oral iron therapy did not reverse these deficits. Consequently, the deficits of the anemic group cannot be unequivocably attributed to iron lack. However, no significant differences were found between anemic and nonanemic groups in birth histories, socioeconomic level, or general nutritional status which might otherwise explain the lower developmental test scores of the anemic babies.

Anemia, Hypochromic↗

Alpha globin gene number: population and restriction endonuclease studies.

Restriction endonuclease analysis was used to test a proposed genetic model using alpha-globin gene number to account for the observed distributions of the proportions of hemoglobin (Hb) S in sickle cell trait. In a subsample of specimens collected during a population survey in India, these studies confirmed that the postulated genotype was present in 22 of the 23 individuals examined. In the study population, the number of alpha-globin genes explains about 90% of the variance in the proportion of HbS in sickle cell trait (r2 = 0.895, p less than 10(-10)).

Anemia, Sickle Cell↗

Sickle cell anemia and trait in southern India: further studies.

Population surveys and family studies among 568 members of nine ethnic groups in southern India identified 15 homozygotes for sickle hemoglobin (HbS)who had mild clinical and hematological manifestations with high levels of fetal hemoglobin (mean=20%, range 8-36%) in a heterogeneous red cell distribution. In one family, the heterozygous mother had a hemoglobin pattern consistent with a form of the heterocellular hereditary persistence of fetal hemoglobin. Sickle cell trait was found in 153(27%) of those studied. Chromatographic quantitation of the hemoglobin fractions in these heterozygotes showed a trimodal distribution of the proportion of HB Sexplicable by a genetic model postulating the presence of genotypes with two (-alpha/-alpha), three (-alpha/alpha alpha) and four (alpha alpha/alpha alpha) active alpha-globin genes. Globin synthesis studies in four heterozygotes believed to have two active alpha-globin genes demonstrated an alpha/non-alpha total activity ratio (0.57) consistent with this model.

Anemia, Sickle Cell↗

Infant care: cache or carry.

To test the hypothesis that a characteristic infant-care pattern existed during most of human history, contemporary hunter-gatherers in a representative sample of world cultures were examined. Numerically coded measures of infant care revealed a uniform pattern. Mothers are the principal caregivers, providing extensive body contact day and night and prolonged breast-feeding. When not carried, the baby of hunter-gatherers has complete freedom of movement. Care is consistently affectionate, with immediate nurturant response to crying. Nonetheless, in most groups, children achieve early independence and by 2 to 4 years spend more than half the time away from the mother. In the United States this pattern of carrying that endured for one to three million years has been replaced by one resembling nesting or caching. Infants spend little time in body contact with caregivers and their movements are restricted by playpens, high chairs, or cribs. Of the minority who are breast-fed, half are weaned within a few weeks. Separate sleeping arrangements and delayed response to crying are regularly recommended. These remarkable transformations may profoundly alter infant development and maternal involvement.

Africa↗

Hemoglobin Hofu or alpha 2 beta 2 [126 (H4) Va1 leads to Glu] found in combination with hemoglobin S.

Hb Hofu, alpha 2 beta 2 [126 (H4) Va1 leads to Glu], was found in 10 members of 2 apparently unrelated Valmiki families in central India. None showed evidence of hemolysis and hemoglobin levels were normal in most. In two individuals, Hb Hofu occurred in combination with Hg S, but neither had clinical manifestations of sickle cell disease. In samples containing Hb Hofu, the isopropanol precipitation test was positive. Quantitation of the hemoglobin fractions by DEAE-cellulose chromatography showed that Hb Hofu constituted a mean of 23--25% of the total whether in combination with Hb A or Hb S.

Female↗

Field methods for the assessment of health and disease in pre-agricultural societies.

The few surviving pre-agricultural societies preserve the best available indication of human adaptation during more than 99% of the species' history. The field methods described allow collection of data that may explain why hunters and gatherers are physically small in the face of apparent plenty, what causes their death and how they control population growth. Observations of daily life, especially family, food and work, provide the context within which biological data can be interpreted. Computer-compatible event-recording systems make possible the collection and encoding of quantitative behavioural observations. A careful census permits characterization of fertility and mortality. Physical assessment, by medical history, physical examination and anthropometry, establishes the patterns of growth and development in the population and the prevalence of clinically recognizable diseases and nutritional disorders. If blood, urine or faeces can be collected, lightweight portable field-proven equipment and techniques are available for the collection, analysis and preservation of specimens for biochemical, nutritional, haematological and genetic determinations.

Adaptation, Biological↗

Sickle cell anemia and trait in a population of southern India.

In an ethnic group in southern India, the Irula, seven individuals with sickle cell anemia were found to manifest only mild illness. Although a relatively high level of fetal hemoglobin was present in one, none of the factors thought to ameliorate the course of sickling disorders could be identified in the remaining six. In a random population survey, sickle hemoglobin was found in 90 of 292 Irula (31%). In those with sickle cell trait, the proportion of sickle hemoglobin in hemolysates (mean = 26%, range 19-32%) was substantially lower than that reported for any other population.

Anemia, Sickle Cell↗

The etiology and porotic hyperostosis among the prehistoric and historic Anasazi Indians of Southwestern United States.

Porotic hyperostosis was studied in 539 crania from maize-growing prehistoric and historic groups who occupied two dissimilar ecological zones of the Plateau country of Arizona and New Mexico--canyon bottoms and sage plain. Defined as abnormal localized sieve-like structural changes involving the hematopoietic areas of the cranium, it was found in 185 (34.3%) of these skulls. More frequent in children than in adults, it shows significant frequency differences between both children and adults of the two ecological zones. The two ecological zones differ in the availability of iron in the diet; the canyon inhabitants depended heavily on maize (which interferes with iron absorption) while the sage plain people consumed more iron-rich animal products. We hypothesize that an increased dependence on maize produced more iron deficiency anemia and resulted in more porotic hyperostosis. Maize is known to have permitted a food surplus which in turn allowed for increased Southwestern population growth in marginal areas like the canyon bottoms. Heavy dependency on a single food type with consequent hematologic problems may have been an important reason for the subsequent abandonment of the Anasazi region.

Adult↗

Kwashiorkor in Cleveland.

Kwashiorkor is uncommon in the United States. Two cases of kwashiorkor were encountered in Cleveland in a short period of time. Both infants had edema, growth failure, irritability, skin and hair changes, and anemia. In each case a major abnormality of feeding had been neither recognized nor corrected during contact with medical personnel. The children did not have milk allergy and both were fed in the hospital without major difficulty, all symptoms resolving with adequate calorie, protein, vitamin, and iron intake. The importance of complete feeding histories is emphasized since such gross protein-calorie malnutrition and its sequelae are preventable.

Breast Feeding↗

The paleoepidemiology of porotic hyperostosis in the American Southwest: Radiological and ecological considerations.

Porotic hyperostosis was observed in 34 percent of 539 crania excavated from sites in Arizona and New Mexico. Common causes of this cranial pathology in the Old World (thalassemia, sickel cell anemia, and malargia) do not explain its occurrence in the American Southwest, as malaria and hemoglobinopathies are not known to have existed in the New World prior to European contact. Iron deficiency anemia which may also be assoicated with porotic hyperostosis occurs on a mass level only with hookworm infestation or nutritionally-related iron deficiency. Since hookworm infestation is rare in the American southwest and has not been reported in prehistoric southwestern American Indians, the hypothesis of nutritional anemia was examined. In canyon bottom sites where the diet was heavily dependent on maize, which is low in iron and also contains an inhibitor of iron absorption, significantly more crania had porotic hyperostosis than in sage plain sites, where the diet included ample animal protein rich in easily absorbable iron (p less than .001). Furthermore, canyon bottom children, who were more susceptible to iron deficiency anemia, had a higher incidence of porotic hyperostosis lesions than adults (p less than .0001).

Adult↗