Insights into gliadin supramolecular organization at digestive pH 3.0.

Alpha-gliadin is a highly immunogenic protein from wheat, which is associated with many human diseases, like celiac disease and non-celiac gluten sensitivity. Because of that, gliadin solution is subject to intense biomedical research. However, the physicochemical nature of the employed gliadin solution at physiological pH is not understood. Herein, we present a supramolecular evaluation of the alpha-gliadin protein in water at pH 3.0 by dynamic light scattering (DLS), cryo-transmission electron microscopy (cryo-TEM) and small-angle-.X-ray scattering (SAXS). We report that at 0.5 wt% concentration (0.1 mg/ml), gliadin is already a colloidal polydisperse system with an average hydrodynamic radius of 30 ±â€¯10 nm. By cryo-TEM, we detected mainly large clusters. However, it was possible to visualise for the first time prolate oligomers of around 68 nm and 103 nm, minor and major axis, respectively. SAXS experiments support the existence of prolate/rod-like structures. At 1.5 wt% concentration gliadin dimers, small oligomers and large clusters coexist. The radius of gyration (Rg1) of gliadin dimer is 5.72 ±â€¯0.23 nm with a dimer cross-section (Rc) of 1.63 nm, and an average length of around 19 nm, this suggests that gliadin dimers are formed longitudinally. Finally, our alpha-gliadin 3D model, obtained by ab initio prediction and analysed by molecular dynamics (MD), predicts that two surfaces prone to aggregation are exposed to the solvent, at the C-terminus. We hypothesise that this region may be involved in the dimerisation process of alpha-gliadin.

Biochemical responses of Solea senegalensis after continuous flow exposure to urban effluents.

Urban effluent potential toxicity was assessed by a battery of biomarkers aimed at determining sub-lethal effects after continuous exposure on the marine organism Solea senegalensis. Specimens were exposed to five effluent concentrations (1/2, 1/4, 1/8, 1/16, 1/32) during 7-days, simulating the dispersion plume at the discharge point. Three different groups of biomarkers were selected in the present study: biomarkers of exposure (Phase I: EROD and DBF; Phase II: GST), biomarkers with antioxidant responses (GR and GPX) and biomarkers of effects (DNA damage and LPO). Additionally, a biological depuration treatment (photobiotreatment (PhtBio)) was tested in order to reduce the adverse effects on aquatic organisms. Effluent exposure caused sub-lethal responses in juvenile fish suggesting oxidative stress. After PhtBio application, concentrations of the major part of measured contaminants were reduced, as well as their bioavailability and adverse effects.

Are the TiO2 NPs a "Trojan horse" for personal care products (PCPs) in the clam Ruditapes philippinarum?

In recent years, increasing quantities of personal care products (PCPs) are being released into the environment. However, data about bioaccumulation and toxicity are scarce; and extraction and analytical approaches are not well developed. In this work, the marine clam Ruditapes philippinarum, selected as model organism, has been employed to investigate bioaccumulation, antioxidant enzyme activities and DNA damage due to exposure to TiO2 nanoparticles and bulk TiO2 (inorganic compounds that are frequent components of PCPs, plastics, paints and coatings, foods and disinfectant water treatments). We have also studied the joint effect of both forms of inorganic TiO2 combined with four organic compounds (mixture exposures) commonly used in PCPs: an antimicrobial (triclosan), a fragrance (OTNE) and two UV filters (benzophenone-3 and octocrylene). Bioaccumulation of the inorganic compound, TiO2, was almost immediate and constant over exposure time. With respect to the organic compounds in mixtures, they were mediated by TiO2 and bioaccumulation is driven by reduced size of the particles. In fact, nanoparticles can be considered as a vector to organic compounds, such as triclosan and benzophenone-3. After a week of depuration, TiO2 NPs and TiO2 bulk in clams showed similar levels of concentration. Some organic compounds with bioactivity (Log Kow >3), like OTNE, showed low depuration after one week. The joint action of the organic compound mixture and either of the two forms of TiO2 provoked changes in enzyme activity responses. However, for the mixtures, DNA damage was found only after the depuration period.

Environmental risk assessment of effluents as a whole emerging contaminant: Efficiency of alternative tertiary treatments for wastewater depuration.

Emerging contaminants (ECs) and regulated compounds (RCs) from three different WWTP effluents were measured in the current study. The efficiency of two tertiary treatments, Photobiotreatment (PhtBio) and Multi-Barrier Treatment (MBT), for removing contaminants was determined. Results indicated different percentages of removal depending on the treatment and the origin of the effluent. Risk Quotients (RQs) were determined for different species of algae, Daphnia, and fish. RQ results revealed diverse risk values depending on the bioindicator species. Tonalide, galaxolide (fragrances), and ofloxacin (antibiotic) were the most persistent and harmful substances in tested effluents. "Negligible risk" category was reached since a wide diversity of ECs were removed by MBT with high removal percentages. Contrarily, PhtBio was effective only in the depuration of certain chemical compounds, and its efficiency depended on the composition of the raw effluent.

Self-assembly of 33-mer gliadin peptide oligomers.

The 33-mer gliadin peptide, LQLQPF(PQPQLPY)3PQPQPF, is a highly immunogenic peptide involved in celiac disease and probably in other immunopathologies associated with gliadin. Herein, dynamic light scattering measurements showed that 33-mer, in the micromolar concentration range, forms polydisperse nano- and micrometer range particles in aqueous media. This behaviour is reminiscent of classical association of colloids and we hypothesized that the 33-mer peptide self-assembles into micelles that could be the precursors of 33-mer oligomers in water. Deposition of 33-mer peptide aqueous solution on bare mica generated nano- and microstructures with different morphologies as revealed by atomic force microscopy. At 6 µM, the 33-mer is organised in isolated and clusters of spherical nanostructures. In the 60 to 250 µM concentration range, the spherical oligomers associated mainly in linear and annular arrangements and structures adopting a "sheet" type morphology appeared. At higher concentrations (610 µM), mainly filaments and plaques immersed in a background of nanospherical structures were detected. The occurrence of different morphologies of oligomers and finally the filaments suggests that the unique specific geometry of the 33-mer oligomers has a crucial role in the subsequent condensation and organization of their fractal structures into the final filaments. The self-assembly process on mica is described qualitatively and quantitatively by a fractal diffusion limited aggregation (DLA) behaviour with the fractal dimension in the range of 1.62 ± 0.02 to 1.73 ± 0.03. Secondary structure evaluation of the oligomers by Attenuated Total Reflection FTIR spectroscopy (ATR-FTIR) revealed the existence of a conformational equilibrium of self-assembled structures, from an extended conformation to a more folded parallel beta elongated structures. Altogether, these findings provide structural and morphological information about supramolecular organization of the 33-mer peptide, which might offer new perspectives for the understanding and treatment of gliadin intolerance disorders.

Understanding recognition and self-assembly in biology using the chemist's toolbox. Insight into medicinal chemistry.

Medicinal chemistry is intimately connected with basic science such as organic synthesis, chemical biology and biophysical chemistry among other disciplines. The reason of such connections is due to the power of organic synthesis to provide designed molecules; chemical biology to give tools to discover biological and/or pathological pathways and biophysical chemistry which provides the techniques to characterize and the theoretical background to understand molecular behaviour. The present review provides some selective examples of these research areas. Initially, template dsDNA organic synthesis and the spatio-temporal control of transcription are presenting following by the supramolecular entities used in drug delivery, such as liposomes and liquid crystal among others. Finally, peptides and protein self-assembly is connected with biomaterials and as an important event in the balance between health and disease. The final aim of the present review is to show the power of chemical tools not only for the synthesis of new molecules but also to improve our understanding of recognition and self-assembly in the biological context.

Water and sanitation associated with improved child growth.

OBJECTIVE: To examine the relation between household water and sanitation, and the risk of stunting and reversal of stunting in Khartoum and Crezira regions, Sudan. DESIGN: Prospective cohort study. SETTING: A total of 25 483 children aged 6-72 months from rural Sudan enrolled in an 18-month field trial in 1988 to study the effect of vitamin A supplementation on child health and survival. RESULTS: The mean height-for-age z-scores at baseline and the end of study were -1.66 and -1.55, respectively, for the group with water and sanitation facilities, and -2.03 and -1.94 for the group without water and sanitation, after adjustment for age, region, gender, mother's literacy, intervention group (vitamin A vs placebo), family wealth, breastfeeding and cleanliness. Among children of normal height-for-age at baseline, the risk of stunting (<-2 height-for-age z-score) was lowest in the group that came from homes that had both water and sanitation compared to children from homes without these facilities (multivariate RR=0.79, 95% CI 0.69-0.90). Among children stunted at baseline, those coming from homes with water and sanitation had a 17% greater chance of reversing stunting than those coming from homes without either facility (adjusted RR=1.17, 95% CI 0.99-1.38). We did not detect a synergistic association between access to water and sanitation. CONCLUSIONS: Water and sanitation are independently associated with improved growth of children. SPONSORSHIP: None.

Biodegradation of phenol in a continuous process: comparative study of stirred tank and fluidized-bed bioreactors.

The paper presents the main results obtained from the study of the biodegradation process of phenol by a pure culture of Pseudomonas putida ATCC 17484. The experimental work was carried out in two different systems: a stirred tank where cells grew as a suspended culture and a fluidized bed where cells were immobilized within calcium alginate gel beads. The influence of the hydraulic residence time (HRT) and organic loading rate on the removal efficiency of phenol was determined for both bioreactors. Also, the stability of the fluidized-bed bioreactor (FBB) in terms of its ability to withstand sudden phenol overdoses is also reported. Experimental values indicated that both bioreactors showed high phenol degradation efficiencies, higher than 90%, even for a phenol loading rate in the influent as high as 4 g phenol/l day. The FBB showed better performance than the suspended-culture bioreactor due to its better control and because it could operate with lower HRT.

Undernutrition and childhood infections: a prospective study of childhood infections in relation to growth in the Sudan.

UNLABELLED: The relationships between both diarrhoea and respiratory infections and linear and ponderal growth were prospectively examined among 28 753 Sudanese pre-school children. Childhood infections were significantly and inversely associated with attained height and attained weight and gain in height and weight over a 6-mo period. They were significantly and positively associated also with stunting after adjusting for age, gender, socio-economic status, dietary variables and previous morbidity. Attained height was on average 17 mm lower (95% CI [-19 -15]) for children with diarrhoea and 11 mm lower (95% CI [-3 -9]) for children with complicated cough than for those without these symptoms. The association between morbidity and attained weight was significant for diarrhoea and complicated cough, but the differences between children with and without symptoms were negligible. The risk of being stunted 6 mo later was 1.38 times (95% CI [1.20 1.59]), 1.29 times (95% CI [0.97 1.72]) and 1.32 times (95% CI [1.13 1.54]) greater among normally-nourished children with diarrhoea, febrile diarrhoea and fever, respectively, than among children without these symptoms. The difference in attained height between children with diarrhoea or complicated cough and those without symptoms increased with age, and was larger among the non-breastfed children compared with breastfed children. CONCLUSION: The results underline the need to reduce child morbidity to prevent the impairment of growth and development.

Dietary vitamin A intake and nondietary factors are associated with reversal of stunting in children.

We examined prospectively the associations between dietary vitamin A intake, nondietary factors and growth in 8174 Sudanese children ages 6-72 mo who were stunted at the start of follow-up. All subjects were weighed and measured at baseline and at 6-mo intervals for 18 mo of follow-up. Dietary vitamin A intake during the prior 24 h was assessed using recall of vitamin A-containing foods at baseline and 6-mo intervals. We examined the association of dietary vitamin A intake with growth and the incidence of recovery of stunting after controlling for age, sex, breast-feeding status and socioeconomic variables. We found that carotenoid intake was associated with a greater incidence of reversal of stunting. Children in the highest quintile grew 13 mm more during the study period than children in the lowest quintile [95% confidence interval (CI): 0-25 mm] in multivariate analyses. The relative risk (RR) of recovery associated with vitamin A intake was greater in infants up to 1 y old (RR = 3.3, CI: 0.9-11.7) than in children > or =3 y of age (RR = 1.0, CI: 0.8-1. 3) (P:-value for interaction = 0.08). Diets rich in carotenoids may increase the rate of recovery from stunting in children. Dietary effects on growth might be strongest among very young children and those who have been most malnourished. Age, sex, breast-feeding status, socioeconomic status and severity of baseline stunting also were associated with reversal of stunting in this population.

Tomato intake in relation to mortality and morbidity among Sudanese children.

The intake of foods that contain high levels of antioxidants may counteract the adverse effects of oxidative stress and lead to improved immune function and reduced risk of infectious disease. We prospectively examined the relationship between the consumption of tomatoes, a rich source of antioxidants, and mortality and diarrheal and respiratory morbidity rates among 28,753 children who were 6-60 mo old and enrolled in a longitudinal study in the Sudan. Children in each household were visited every 6 mo for a maximum of four visits. At each round, mothers recalled whether a child had consumed tomatoes in the previous 24 h. Events (death or morbidity) reported at each round were prospectively allocated according to the number of days of tomato intake. Intake of tomatoes for 2 or 3 d compared with none was associated, respectively, with 48% (relative risk, 0. 53; 95% confidence interval, 0.30-0.91) and 83% (0.17; 0.04-0.72) reductions in morality rates (P: for trend = 0.002). The association between tomato use and death remained statistically significant (P: for trend = 0.004), even after further adjustment for total vitamin A intake. Tomato intake was also associated with a reduced risk of death associated with diarrhea in the week preceding death (P: for trend = 0.009) or fever (P: for trend = 0.04). Intake of tomatoes was also inversely and significantly associated with the risks of diarrheal and respiratory infections. Our data suggest that tomatoes may be beneficial for child health but also emphasize the general importance of food-based approaches to the prevention of micronutrient malnutrition and protection of the health of children in developing countries.

Undernutrition in relation to childhood infections: a prospective study in the Sudan.

OBJECTIVE: The aim of the study was to examine the relationships between nutritional status and diarrhoea and respiratory infections. DESIGN: Prospective cohort study within the framework of a randomized double-blind placebo-controlled intervention trial. SETTING: In rural communities in the Khartoum and Gezira regions, in Northern Sudan. SUBJECTS: 28,753 Sudanese pre-school children between 6 months and 6 y old. METHODS: Relative risks of subsequent diarrhoea and respiratory infections in relation to nutritional status measured by anthropometry (Z-scores of height-for-age (H/A), weight-for-height (W/H), and weight-for-age (W/A), which reflect stunting, wasting and underweight, respectively) were estimated using odds ratios from logistic regression adjusting for various covariates. RESULTS: H/A, W/H and W/A were significantly and inversely associated with subsequent diarrhoea and febrile diarrhoea (P for trend <0.001) with risks being 2.00 times higher (95% confidence interval, CI (1.64, 2.43)) among children with W/A Z-scores below -4 Z, and 1.75 times higher (95% CI (1.56, 1.96)) among those with a W/A Z-score between -4 and -3 Z compared with children having a W/A Z-score > or =1. Age, gender, region of residence and seasonality modified these associations. Also, febrile cough was inversely associated with W/A and W/H (P<0.03), with risks ranging from 1.41 times higher (95% CI (1.02, 1.97)) to 1.21 times higher (95% CI (1.04, 1.41)) in the group of underweight children with W/A Z-scores below -4 and between -2 and -1 Z, all compared with normally nourished children (> or =-1 Z). CONCLUSIONS: The reduction of severe but also mild and moderate undernutrition is necessary through nutrition, health and socio-economic improvement in order to prevent morbidity.

Reduced visual resolution acuity and cerebral white matter damage in very-low-birthweight infants.

Neonatal cerebral white matter echolucencies predict visual resolution acuity deficits in very-low-birthweight (VLBW) infants. We examined maternal sociodemographic, lifestyle, intrapartum, infant birth/perinatal, and ocular motor/refractive characteristics to determine whether they accounted for this association in infants who were tested once between postnatal age 25 and 56 weeks (corrected for gestational age at birth). Cranial ultrasound scans were read by consensus to identify echolucency in a population of VLBW infants with no known ocular abnormalities. Visual resolution acuity was measured with the Acuity Card Procedure (ACP) in 14 infants with echolucency and compared with that of 81 VLBW infants born in the same hospitals with normal ultrasound scans. In time-oriented logistic regression models, echolucency remained a consistent predictor of abnormal visual resolution acuity after adjustment for covariates in three developmental periods (pre-, peri-, and postnatal). Odds ratios ranged from 19.3 (95% confidence interval, 4.5 to 82.2; p=0.001) to 10.4 (95% confidence interval, 1.3 to 81.9; p=0.03). Reduced visual resolution acuity in VLBW infants appears to be due to cerebral white matter damage.

A randomized trial of vitamin A supplements in relation to mortality among human immunodeficiency virus-infected and uninfected children in Tanzania.

OBJECTIVES: To determine whether vitamin A supplements result in reduced mortality among HIV-infected and uninfected children. DESIGN: Randomized, double blind, placebo-controlled trial. METHODS: Starting in April, 1993, we randomized 687 children age 6 months to 5 years who were admitted to the hospital with pneumonia. Children who were severely malnourished or had clinical signs of vitamin A deficiency were excluded. At baseline children received placebo or 400 000 IU (or half that for infants) of vitamin A, in addition to standard treatment for pneumonia. They received further doses of the same regimen 4 and 8 months after hospital discharge. Sera from children were tested for HIV antibodies by enzyme-linked immunosorbent assay and Western blot tests. For positive children <15 months of age, HIV infection was confirmed by amplified heat-denatured HIV-p24 antigen assays with confirmatory neutralization assays. HIV status was ascertained for 648 of 687 enrolled children. The mean duration of follow-up was 24.4 months (SD = 12.1). RESULTS: Of 648 children 58 (9%) were HIV-infected. Compared with uninfected children, all-cause mortality was higher among HIV-infected children, as was mortality caused by pneumonia or diarrhea (P < 0.001 for each). Overall vitamin A supplements resulted in a 49% reduction in mortality [relative risk (RR), 0.51; 95% confidence interval (CI), 0.29 to 0.90, P = 0.02]. Vitamin A supplements reduced all-cause mortality by 63% among HIV-infected children (RR 0.37; CI 0.14 to 0.95, P = 0.04) and by 42% among uninfected children (RR 0.58, CI 0.28 to 1.19, P = 0.14). Vitamin A supplements were also associated with a 68% reduction in AIDS-related deaths (P = 0.05) and a 92% reduction in diarrhea-related deaths (P = 0.01). CONCLUSION: Vitamin A deficiency, which is common among children in many developing countries, is particularly severe among HIV-infected children. Our findings indicate that vitamin A supplements, a low cost intervention, reduce mortality of HIV-infected children.

Vitamin A supplementation and severity of pneumonia in children admitted to the hospital in Dar es Salaam, Tanzania.

Vitamin A deficiency and acute lower respiratory tract infections coexist as important public health problems in many developing countries. We carried out a randomized, double-blind, placebo-controlled trial to examine whether large doses of vitamin A given to Tanzanian children who are admitted to the hospital with nonmeasles pneumonia would reduce the severity of respiratory disease. Six hundred eighty-seven children were randomly assigned to receive either placebo or vitamin A [200 000 IU (60 mg retinol equivalents) for children > 1 y of age and 100000 IU (30 mg retinol equivalents) for infants] on the day of admission and another dose on the following day. Of the 346 children in the vitamin A group, 13 died in the hospital, compared with 8 of 341 children in the placebo group; the relative mortality was 1.63 (95% CI: 0.67, 3.97; P = 0.28). The mean number of days of hospitalization was the same in both groups (4.2 d). There were no differences between the vitamin A and placebo groups in the duration of hospital stay when examined within categories of children stratified by age, sex, breast-feeding status, nutritional status at baseline, or quartile of dietary vitamin A intake in the 4 mo before admission to the hospital. There were also no differences in the mean number of days of fever, rapid respiratory rate, or hypoxia, whether these endpoints were examined in the total number of subjects or in a subset with more severe clinical conditions at baseline. Large doses of vitamin A had no protective effect on the course of pneumonia in hospitalized Tanzanian children.

A longitudinal study of prolonged breastfeeding in relation to child undernutrition.

BACKGROUND: In a number of studies prolonged breastfeeding was associated with a higher risk of undernutrition, although most of these studies are limited by their cross-sectional design which does not allow examination of temporal relationships between full weaning and undernutrition. METHODS: The relationship between prolonged breastfeeding and child growth was examined prospectively among children under 36 months old who participated in a large cohort study. At baseline and at each of three 6-monthly follow-up visits breastfeeding status was assessed and all subjects were weighed and measured. RESULTS: Undernourished children were more likely to be breastfed for a longer period of time compared with normal children. We found a small difference between breastfed and fully weaned children in the gain in height over the following 6-month period; however, breastfed children were likely to gain significantly less weight, particularly among children who were aged 6-12 months. Similar findings were noted when these associations were examined among children who were normally nourished at the time of breastfeeding assessment. The inverse association between breastfeeding status and weight gain was significantly larger among children of poor or illiterate mothers compared with children of relatively more affluent or literate mothers, respectively. CONCLUSIONS: Our findings suggest that the inverse association is not causal, and may be explained by poorer complementary feeding among breastfed compared with weaned children. Children from poorer households and whose parents are illiterate are more likely to have less than adequate complementary feeding. The importance of adequate complementary feeding in the second half of infancy needs to be stressed in nutrition education programmes.

PIP: The relationship between prolonged breast feeding and growth was investigated in a prospective study of 28,753 Sudanese children under 36 months of age enrolled in a broader cohort study of child health and nutrition. 81% of children were breast-fed at 12 months, but this prevalence declined to 62% at 18 months and 27% at 24 months. Stunted or wasted children were more likely to be breast-fed for a longer period of time than their well-nourished counterparts. There was only a small difference between breast-fed and fully weaned children in 6-month height gains; however, breast-fed children gained significantly less weight, especially in the 6-12-month age group. The inverse association between breast feeding status and weight gain was significantly larger among children of poor or illiterate mothers than those of literate, more affluent mothers. It is postulated that this inverse association is a result of poorer complementary feeding among breast-fed compared with weaned children, especially in low-income households. These findings suggest a need for nutrition education programs to emphasize the need for adequate complementary feeding in the second half of infancy.

The effect of vitamin A supplementation on the growth of preschool children in the Sudan.

OBJECTIVES: This study assessed the effect of vitamin A supplementation at 6-month intervals on child growth. METHODS: Sudanese children (n = 28,740) 6 to 72 months of age were weighed and measured at baseline and at each of three follow-up visits. RESULTS: Periodic vitamin A supplementation had no effect on the rate of weight or height gain in the total population or on the incidence of wasting, stunting, or wasting and stunting among children who were normally nourished at baseline. CONCLUSIONS: Reducing poverty and improving access to adequate diets should remain the goals of programs designed to improve the nutritional status of malnourished populations.

Dietary vitamin A intake in relation to child growth.

Severe deficits in ponderal and linear growth are problems of major public health significance among children in developing countries. We prospectively examined the association of dietary vitamin A intake with child growth among 28,740 Sudanese children ages 6-72 months. At baseline and at each 6-month visit, all subjects were weighed and measured. Dietary vitamin A intake during the prior 24 hours was assessed using recall of vitamin A-containing foods. Dietary vitamin A intake was associated with attained height and weight after controlling for age, sex, morbidity, and socioeconomic variables. Compared with children in the bottom quintile of intake, those in the top quintile were 11 mm taller [95% confidence interval (CI) = 8-13] and 237 gm heavier (95% CI = 153-320). Higher dietary vitamin A intake was also associated with reduced risk of stunting [relative risk (RR) for 5th vs 1st quintile = 0.7; 95% CI = 0.5-0.9] and wasting (RR = 0.7; 95% CI = 0.5-0.9). Adequate intake of foods containing vitamin A may improve child growth where vitamin A deficiency prevails, but this relation may not be due to vitamin A per se.

Risk factors of low dietary vitamin A intake among children in the Sudan.

We examined the determinants of dietary vitamin A intake among Sudanese children, information which is important for designing effective interventions based on the dietary approach. Children under the age of two years were at greater risk of consuming a diet low in vitamin A compared with children who were five years or older. Compared with children from relatively affluent households, those from poorer households were about twice as likely to consume low levels of carotenoid or preformed vitamin A. Low vitamin A intake was also significantly associated with lack of running water, a latrine, radio, or television in the household, and inversely associated with maternal or paternal illiteracy and with cleanliness of the child subjectively assessed by the interviewer. As expected, breastfed children in the first two years of life were likely to consume lower levels of preformed vitamin A and carotenoid from food (excluding breast milk) compared with non-breastfed children. Low vitamin A intake was more prevalent in the dry months of the year. Efforts to increase accessibility to vitamin A containing food, combined with nutrition education campaigns and public health programmes directed at improving sanitation and reducing infection are necessary as part of the long-term solution to the problem of vitamin A deficiency.

PIP: Although the importance of vitamin A as a nutrient for child survival and health has been known for a long time, vitamin A deficiency continues to be a public health problem. Approximately 2.8 million children aged 0-4 years have xerophthalmia and another estimated 251 million have moderate to severe subclinical deficiency. Findings are reported from an investigation of the determinants of dietary vitamin A intake among 28,753 Sudanese children aged 6-72 months. The study was placebo-controlled and spanned a 2-year follow-up period. Children under age 2 years were at greater risk of consuming a diet low in vitamin A compared with children aged 5 years or older, while children from relatively poor households were about twice as likely to consume low levels of carotenoid or preformed vitamin A. Low vitamin A intake was also significantly associated with lack of running water, a latrine, radio, or television in the household, and inversely associated with maternal or paternal illiteracy and with cleanliness of the child as subjectively assessed by the interviewer. Children breast fed during their first 2 years of life were likely to consume lower levels of preformed vitamin A and carotenoid from food (excluding breast milk) relative to non-breast-fed children, and low vitamin A intake occurred more during the dry months of the year. A need exists to increase accessibility to vitamin A-containing foods and to have nutrition education campaigns and public health programs directed at improving sanitation and reducing infection as part of the long-term solution to vitamin A deficiency.

A prospective study of malnutrition in relation to child mortality in the Sudan.

We examined prospectively the relation between malnutrition and mortality among Sudanese children. A cohort of 28753 children between the ages of 6 mo and 6 y was examined every 6 mo for 18 mo. Two hundred thirty-two children died during 18 mo of follow-up (480624 child-months). Low weight-for-height was associated with an increased risk of mortality (P < 0.0001). Even children with Z scores between -1 and -2 were 50% more likely to die in the following 6 mo than were children with Z scores > -1 (multivariate relative mortality: 1.5; 95% CI: 1.1, 2.2). There was also an inverse relation between height-for-age and mortality (P < 0.0001). Among breast-fed children, the relative mortality associated with a Z score for weight-for-height of < -3 compared with > -2 was 7.3 (95% CI: 3.3, 15.9); among children not breast-fed, it was 26.0 (95% CI: 12.8, 53.0; P for interaction = 0.001). A strong and significant synergy was also found between infection and wasting or stunting as predictors of child mortality (P for interaction = 0.001 and 0.02. respectively). In developing countries, children who are below the customary cutoff point of -2 Z for weight-for-height may be at higher risk of death. Breast-feeding and reduction of morbidity should be advocated in programs designed to reduce malnutrition and mortality among children.

PIP: The authors prospectively examined the relation between malnutrition and mortality in a cohort of 28,753 Sudanese children aged 6 months to 6 years. Children in the cohort were examined every 6 months for 18 months, during which 232 children died. Low weight-for-height was significantly associated with an increased risk of mortality. Even children with Z scores between -1 and -2 were 50% more likely to die in the following 6 months than were children with Z scores greater than -1. A significant inverse relation was identified between height-for-age and mortality. Among breast-fed children, the relative mortality associated with a Z score for weight-for-height of less than -3 compared with greater than -2 was 7.3, 26.0 among non-breast-fed children. A strong and significant synergy was also found between infection and wasting or stunting as predictors of child mortality. These findings indicate that children in developing countries who are below the customary cutoff point of -2 Z for weight-for-height may be at greater risk of death. Breast feeding and the reduction of morbidity should be advocated in programs designed to reduce malnutrition and mortality among children.