Biomedical subjects

W E Watkins

Publications and source records attributed to W E Watkins.

11 recordsLinked to original sources

PubMed1997

"Stupidity or worms": do intestinal worms impair mental performance?

The title of a 1930s article asked the question, "Stupidity or Hookworm?" In this article, the authors discuss research that attempts to answer the question of whether intestinal worms--namely, hookworm, whipworm, and roundworm--harm the mental performance of their hosts. After introducing the biology and epidemiology of intestinal worms, the authors present the historical background to the problem. They review research from the 1910s through the 1990s; there is evidence that high intensities of worms can affect mental performance, but not all dewormed children show improved performance. They discuss the mechanisms of how worms might affect the mind.

Ancylostomatoidea↗

PubMed1997

Three-month nutritional supplementation in Indonesian infants and toddlers benefits memory function 8 y later.

Does short-term supplementary feeding during infancy and childhood have long-lasting effects? In 1986, 334 children aged 6-60 mo living on rural tea plantations in West Java, Indonesia, participated in a 3-mo randomized trial to test the effects of a dietary supplement providing approximately 1672 kJ (400 kcal) energy/d, with about the same nutrient density as local foods. We returned to the same communities in 1994 and enrolled 231 (125 supplemented, 106 control) of the original subjects in a follow-up study of the long-term effects of supplementation. We assessed these subjects by using several measures: anthropometry, iron status, information processing, Peabody Picture Vocabulary Test, word fluency, and an arithmetic test. The supplemented group showed no differences from those in the control group. However, when the analysis was limited to subjects who had received the supplement before the age of 18 mo (n = 73), the supplemented children performed better than control children on the Sternberg test of working memory (decision time intercept: probe absent, P = 0.002; probe present, P = 0.053). After considering possible confounders, we concluded that the supplementation during infancy was responsible for the difference. This finding shows that supplementation can have long-lasting effects on a specific domain if the child receives it at the appropriate stage of development.

Anthropometry↗

PubMed1996

Effect of removing Ascaris on the growth of Guatemalan schoolchildren.

OBJECTIVE: To determine whether successful deworming for 6 months in children with high levels of Ascaris improves physical growth. SUBJECTS: Two hundred twenty-eight children (mean age, 9.7 years) in a highland Indian town in Guatemala. DESIGN: Children were randomly assigned to receive albendazole or placebo at baseline and 12 weeks. Children and field workers were both blind to the group assignment. OUTCOME MEASURES: Children's heights, weights, and mid-upper-arm circumferences were measured at baseline and 12 and 24 weeks. Fecal egg counts were taken at 0, 2, 12, 14, and 24 weeks to estimate the helminth burden (eggs per gram of feces [epg]). RESULTS: Baseline helminth prevalences were Ascaris, 91%, and Trichuris, 82%. Ascaris intensities were high: half of the children had moderate burdens (10 000 to 50 000 epg), and 25% had heavy burdens ( > 50 000 epg). Trichuris burdens were light (72% < 1000 epg). The albendazole and placebo groups did not differ at baseline in epg, age, anthropometry, or socioeconomic status. The two rounds of treatment successfully reduced the Ascaris burdens but had less effect on Trichuris. At 6 months the treatment group showed a small gain in weight (0.18 kg) compared with the placebo group but no improvement in height or mid-upper-arm circumference. CONCLUSIONS: The successful removal of ascaris in a population of school-aged children with relatively high loads may have modest effects on weight gain. Ascaris is one of the most common infections in school-aged children, but its effect on the host may be less than that of other helminths.

Albendazole↗

PubMed1994

Adverse effect of iron supplementation on weight gain of iron-replete young children.

The efficacy of iron supplementation for iron-deficient subjects is in no doubt. However, the assumption that iron supplementation of iron-replete subjects is harmless may not be valid. We have studied the effect of iron supplementation on growth rate in 47 iron-sufficient young children (12-18 months) in Indonesia. The children were randomly assigned either ferrous sulphate (3 mg/kg daily) or placebo every day for 4 months. Before treatment the length, weight, and arm circumference of the two groups were similar. During the 4 months of supplementation the rate of weight gain was significantly greater in the placebo group than in the iron-supplemented group (0.106 [SE 0.010] vs 0.070 [0.011] kg every 2 weeks, p = 0.02). The rates of gain in length and arm circumference did not differ significantly by treatment. There were no differences between the groups in rates of respiratory and gastrointestinal infections. These results suggest that iron supplementation of iron-replete children may retard their growth.

Analysis of Variance↗

PubMed1991

Characteristics of 16-dehydroprogesterone reductase in cell extracts of the intestinal anaerobe, Eubacterium sp. strain 144.

16-Dehydroprogesterone reductase (16-DHPR) activity was present in cell extracts of Eubacterium sp. strain 144 only when the organism was grown in the presence of steroids containing a delta 16-17 double bond and C-20-ketone. Cells grown with 16-dehydropregnenolone contained 16-DHPR activity but lacked delta 4-5-3-keto steroid reductase activity. Pyruvate or sodium dithionite served as electron donors for 16-DHPR and both reactions required methyl viologen as an electron carrier. Neither NADH nor NADPH, with or without flavin nucleotides, were used by 16-DHPR. Enzyme activity was detected in the cytoplasmic fraction (40%) and membrane fraction (20%) of crude cell extracts, but 40% of the activity was unaccounted for following ultracentrifugation. 16-DHPR activity was unaffected by pH in potassium phosphate buffer over the range 5.0 to 8.5, but was inhibited by Tris-HCl above pH 7.0. 16-DHPR activity was inhibited by sulfhydryl reagents, but inhibitors of electron transport reactions or metal chelators did not affect the enzyme.

Cell Membrane↗

PubMed1973