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1.
Nat Commun ; 11(1): 6003, 2020 Nov 26.
Article in English | MEDLINE | ID: mdl-33243978

ABSTRACT

Nickelates are a rich class of materials, ranging from insulating magnets to superconductors. But for stoichiometric materials, insulating behavior is the norm, as for most late transition metal oxides. Notable exceptions are the 3D perovskite LaNiO3, an unconventional paramagnetic metal, and the layered Ruddlesden-Popper phases R4Ni3O10, (R = La, Pr, Nd). The latter are particularly intriguing because they exhibit an unusual metal-to-metal transition. Here, we demonstrate that this transition results from an incommensurate density wave with both charge and magnetic character that lies closer in its behavior to the metallic density wave seen in chromium metal than the insulating stripes typically found in single-layer nickelates like La2-xSrxNiO4. We identify these intertwined density waves as being Fermi surface-driven, revealing a novel ordering mechanism in this nickelate that reflects a coupling among charge, spin, and lattice degrees of freedom that differs not only from the single-layer materials, but from the 3D perovskites as well.

2.
Lupus ; 21(2): 128-35, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22235042

ABSTRACT

OBJECTIVE: To investigate the clinical, laboratory and histological manifestations of patients who received illegal injections of foreign substances for cosmetic purposes. PATIENTS AND METHODS: We studied patients who met the following inclusion criteria: 1) history of application of foreign substances for cosmetic purposes, 2) clinical data of autoimmune disease or non-specific autoimmune manifestation (i.e. arthralgias, myalgia, malaise, fever, and weight loss), 3) detection of autoantibodies in patients' sera, 4) histological evidence of chronic inflammation and/or granulomatous reaction to foreign body. RESULTS: Fifty female patients aged 44.4 ± 10 years were studied. The mean time between application of foreign substances and onset of symptoms was 4.5 ± 4.3 years. Patients were followed for 12 ± 7.5 years. Forty-one patients were injected with mineral oil, nine patients received other substances: three iodine gadital, one guayacol, one guayacol plus silicone fluid, two collagen, two silicone fluid. The sites of application were: buttocks (36), legs and/or thighs (11), breasts (eight) hands and face (one), face (two) (seven patients received an injection to more than one site). Thirty patients presented with non-specific autoimmune manifestations, whereas 20 patients fulfilled the criteria for a defined autoimmune disease such as systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, overlap syndrome, autoimmune hemolytic anemia, autoimmune thyroiditis, autoimmune hepatitis, and ulcerative colitis. CONCLUSIONS: Cases of human adjuvant disease following illegal injections of oil substances for cosmetic purposes are reported. Patients presented with defined autoimmune diseases as well as with non-specific autoimmune manifestations. Illegal injection of these substances could lead to serious local and systemic complications, even to death. These cases represent another model of Autoimmune/inflammatory Syndrome Induced by Adjuvants (ASIA). The use of these substances should be prohibited.


Subject(s)
Adjuvants, Pharmaceutic/adverse effects , Autoimmune Diseases/chemically induced , Cosmetic Techniques/adverse effects , Foreign Bodies/immunology , Adolescent , Adult , Autoimmune Diseases/immunology , Autoimmune Diseases/pathology , Autoimmune Diseases/physiopathology , Cosmetic Techniques/ethics , Female , Humans , Middle Aged , Syndrome , Young Adult
3.
Eur J Clin Nutr ; 65(1): 20-5, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20842166

ABSTRACT

BACKGROUND/OBJECTIVES: Ferrous fumarate is recommended for the fortification of complementary foods based on similar iron absorption to ferrous sulfate in adults. Two recent studies in young children have reported that it is only 30% as well absorbed as ferrous sulfate. The objective of this study was to compare iron absorption from ferrous fumarate and ferrous sulfate in infants, young children and mothers. SUBJECTS/METHODS: Non-anemic Mexican infants (6-24 months), young children (2-5 years) and adult women were randomly assigned to receive either 4 mg Fe (women) or 2.5 mg Fe (infants and young children) as either [(57)Fe]-ferrous fumarate or [(58)Fe]-ferrous sulfate added to a sweetened drink based on degermed maize flour and milk powder. Iron absorption was calculated based on incorporation of isotopes into erythrocytes after 14 days. RESULTS: Within each population group, no significant differences (P > 0.05) in iron absorption were found between ferrous fumarate and ferrous sulfate. Mean iron absorption from ferrous fumarate vs ferrous sulfate was 17.5 vs 20.5% in women (relative bioavailability (RBV) =86), 7.0 vs 7.2% in infants (RBV = 97) and 6.3 vs 5.9% in young children (RBV = 106). CONCLUSIONS: Ferrous fumarate is as well absorbed as ferrous sulfate in non-anemic, iron sufficient infants and young children, and can be recommended as a useful fortification compound for complementary foods designed to prevent iron deficiency. Further studies are needed to clarify its usefulness in foods designed to treat iron deficiency.


Subject(s)
Dairy Products , Ferrous Compounds/administration & dosage , Food, Fortified , Zea mays/metabolism , Adult , Anemia, Iron-Deficiency/prevention & control , Beverages , Biological Availability , Child, Preschool , Drug Evaluation , Female , Ferrous Compounds/pharmacokinetics , Ferrous Compounds/pharmacology , Flour , Humans , Infant , Intestinal Absorption , Iron/blood , Iron, Dietary/administration & dosage , Iron, Dietary/pharmacokinetics , Linear Models , Mexico , Sweetening Agents
4.
J Nutr ; 137(2): 440-6, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17237324

ABSTRACT

In Mexico, the potential impact on child malnutrition from a nutritional supplement (papilla) delivered through a conditional transfer program (Oportunidades) was attenuated by problems of household utilization. A behavioral change through communication intervention was developed to improve supplement utilization. Our study assessed the efficacy of this intervention through the results of a randomized trial. In 2 states (Veracruz and Chiapas) 2 clusters of communities were randomly assigned to intervention or control groups. Data were obtained from 176-198 mothers in intervention and control communities using a survey questionnaire at preintervention baseline and at a 5-mo follow-up. Concordance between reported and observed behaviors was examined through an observational substudy. The 4 behavioral recommendations were: 1) prepare papilla as a pap; 2) administer the preparation every day; 3) administer it between breakfast and dinner; and 4) administer it only to target children. The intervention resulted in a significant increase (P<0.05) in the prevalence of reported correct behaviors in the intervention group compared with the control for 3 of the behaviors: a mean increase of 42.5% for preparing papilla as pap, 64.4% for daily administration, and 61.5% for giving papilla between breakfast and dinner. Administering to a target child increased significantly in Veracruz (from 51.5% to 90.6%), but not in Chiapas (20.6% to 33.3%). Reported behaviors agreed with observed behaviors in the substudy. With the exception of the target-child administration in Chiapas, adopting the recommendations was culturally acceptable and feasible. The results indicate that improvements in household utilization of the supplement can be achieved with a communication intervention that is potentially feasible for implementation on a large scale within the Oportunidades Program.


Subject(s)
Child Nutritional Physiological Phenomena , Dietary Supplements , Health Behavior , Health Education , Micronutrients/administration & dosage , Mothers/psychology , Adult , Child, Preschool , Female , Humans , Infant , Male , Mexico
5.
Am J Clin Nutr ; 74(5): 657-63, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11684535

ABSTRACT

BACKGROUND: The role of single micronutrient deficiencies in the etiology of growth retardation has recently gained attention. However, because multiple micronutrient deficiencies are common in children in developing countries, it is possible that more than one micronutrient may limit growth and, hence, the correction of a single deficiency may not be enough to improve growth substantially. OBJECTIVE: The objective was to evaluate the effect of multiple micronutrient supplementation on the growth of children aged 8-14 mo whose diets were poor in several micronutrients. DESIGN: Children were randomly assigned to 1 of 2 groups. One group received a multiple micronutrient supplement containing the recommended dietary allowance (RDA) or 1.5 times the RDA of vitamins A, D, E, K, C, B-1, B-6, B-12, riboflavin, niacin, biotin, folic acid, and pantothenic acid, and iron, zinc, iodine, copper, manganese, and selenium. The other group received a placebo. Supplements were administered 6 d/wk for an average of 12.2 mo. Body length was measured at baseline and monthly thereafter until the end of supplementation. RESULTS: Supplemented infants initially aged <12 mo had significantly greater length gains than did the placebo group, with a difference of 8.2 mm (length-for-age z score: 0.3) at the end of supplementation. In contrast, differences in length gains between the supplemented and placebo groups initially aged > or =12 mo were not significant. CONCLUSIONS: Micronutrient deficiencies limited the growth of the Mexican infants studied. Improving micronutrient intakes should be a component of interventions to promote growth in infants living in settings where micronutrient intakes are inadequate.


Subject(s)
Body Height/drug effects , Dietary Supplements , Growth Disorders/etiology , Growth/drug effects , Micronutrients/administration & dosage , Age Factors , Body Height/physiology , Child Development , Double-Blind Method , Female , Growth/physiology , Growth Disorders/epidemiology , Growth Disorders/prevention & control , Humans , Infant , Male , Mexico , Micronutrients/pharmacology
6.
J Nutr ; 128(3): 556-62, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9482763

ABSTRACT

The impact of zinc supplementation on the growth and body composition of Guatemalan infants was assessed in a community-based, double-blind intervention trial. Infants aged 6-9 mo were assigned randomly to receive 4 mL of a beverage containing 10 mg of zinc as zinc sulfate (n = 45) or a placebo (n = 44) daily (7 d/wk) for an average of 6.9 mo. The children's weight, length, mid-upper arm and head circumferences, and triceps skinfolds were measured at baseline and at 1-2 mo intervals until the end of supplementation. Midarm muscle area (MMA) was derived from the mid-upper arm circumference and triceps skinfolds measurements. Maternal anthropometry and family socioeconomic and demographic characteristics also were obtained. Zinc supplementation was associated with an overall increase of 0.61 cm2 in MMA (P = 0.02). Children who received zinc supplements had a mean length increment that was 0.75 cm greater than those who did not (P = 0.12). However, there was a significant interaction between treatment group and initial length-for-age status (P = 0.04), such that supplemented children who were stunted at baseline (length-for-age Z score less than -2) gained 1.40 cm more than stunted children who received the placebo. We conclude that zinc supplementation of these rural Guatemalan infants during 6. 9 mo increased accretion of fat-free mass and enhanced the linear growth of those who were stunted at baseline. Further research is required to determine whether zinc supplementation during longer periods of time may achieve larger and more generalized effects on physical growth.


Subject(s)
Child Development/drug effects , Dietary Supplements , Growth Disorders/drug therapy , Rural Population , Zinc/administration & dosage , Body Composition/drug effects , Double-Blind Method , Growth Disorders/pathology , Guatemala , Humans , Infant , Regression Analysis , Zinc/therapeutic use
7.
Poult Sci ; 76(11): 1531-4, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9355147

ABSTRACT

The purpose of the present study was to test the suitability of the solids of nejayote (a waste product from the tortilla industry) in diets for broilers. The nejayote was obtained from two different tortilla-making factories and the solids were obtained by centrifuge then dried in a hot-air drier. Diets were formulated to be isocaloric and isonitrogenous according to the NRC dietary requirements (1994). Nejayote solids were supplemented at 2, 4, and 6% of the diet. Results show that the content of protein and calcium in the dried solids of nejayote were 5 and 13%, respectively. The performance of broilers fed diets supplemented with dried nejayote did not differ from that of those fed the control diet. Therefore, it is concluded that nejayote solids are suitable for broiler feed and do not affect growth performance. Utilization of nejayote solids at higher levels is a possibility provided that no adverse effects on body weight, feed utilization, and feed:gain ratios are observed.


Subject(s)
Chickens/growth & development , Diet/veterinary , Food Industry/methods , Waste Products , Animals , Calcium, Dietary/analysis , Calcium, Dietary/pharmacology , Chickens/physiology , Dietary Proteins/analysis , Dietary Proteins/pharmacology , Eating/physiology , Random Allocation , Weight Gain/physiology
8.
J Nutr ; 127(7): 1333-8, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9202087

ABSTRACT

Zinc deficiency has been associated with growth deficits, reduced dietary intake and appetite, and has been hypothesized to result in reduced activity. This randomized, double-blind, placebo-controlled study examined whether 10 mg of oral zinc as zinc sulfate, given daily for up to 7 mo, affected activity patterns of 85 Guatemalan infants recruited at 6-9 mo of age. Infant activity was assessed by time sampling-observation method at 10-min intervals during a 12-h data collection period, at base line, 3 and 7 mo follow-up. Motor development and the percentage of time infants were observed in various positions (being carried, lying down, sitting, crawling, standing or walking) and engaged in various activities (eating, sleeping, resting, crying/whining or playing) were compared by treatment group. No differences in motor development were observed by treatment group. However, at follow-up 2 (after 7 mo of supplementation), zinc-supplemented infants were significantly more frequently observed sitting up compared with lying down, and were playing during 4.18 +/- 1.95% (P < 0.05) more observations than unsupplemented infants. They were also somewhat less likely to be observed crying or whining (P < 0.10) compared with those receiving the placebo. These effects are independent of other factors including infant age, motor development, sex, maternal education, family socioeconomic status and nutritional status at base line. Further research must be conducted to determine the long-term developmental importance of these differences in activity patterns associated with zinc supplementation in this setting.


Subject(s)
Motor Activity/drug effects , Zinc Sulfate/pharmacology , Zinc/deficiency , Administration, Oral , Child Development/physiology , Diarrhea, Infantile/epidemiology , Double-Blind Method , Feeding Behavior/physiology , Female , Food, Fortified , Guatemala/epidemiology , Humans , Incidence , Infant , Life Style , Male , Motor Activity/physiology , Nutritional Status , Rural Health , Sleep/physiology , Social Class , Time Factors , Zinc/administration & dosage , Zinc Sulfate/administration & dosage , Zinc Sulfate/therapeutic use
9.
Pediatrics ; 99(6): 808-13, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9164774

ABSTRACT

OBJECTIVE: A community-based, randomized, double-blind intervention trial was conducted to measure the impact of zinc supplementation on young Guatemalan children's morbidity from diarrhea and respiratory infections. METHODS: Children aged 6 to 9 months were randomly assigned to receive 4 mL of a beverage containing 10 mg of zinc (as zinc sulfate) daily (7 d/wk) for 7 months (n = 45) or a placebo (n = 44). Morbidity data were collected daily. Diagnoses of diarrhea, fever, and anorexia were based on mothers' definitions. Respiratory infections were defined as the presence of at least two of the following symptoms: runny nose, cough, wheezing, difficulty breathing, or fever. RESULTS: High rates of diarrhea and respiratory infections were reported. Children from the placebo group had a 20% episodic prevalence of diarrhea, with 8 episodes/100 d, and a 7% episodic prevalence of respiratory infections, with 3 episodes/100 d. The median incidence of diarrhea among children who received zinc supplementation was reduced by 22% (Wilcoxon rank test), with larger reductions among boys and among children with weight-for-length at baseline lower than the median of the sample (39% reductions in both subgroups). Zinc supplementation also produced a 67% reduction in the percentage of children who had one or more episodes of persistent diarrhea (chi2 test). No significant effects were found on the episodic prevalence of diarrhea, the number of days per episode, or the episodic prevalence or incidence of respiratory infections. CONCLUSIONS: The large impact of zinc supplementation on diarrhea incidence suggests that young, rural Guatemalan children may be zinc deficient and that zinc supplementation may be an effective intervention to improve their health and growth.


Subject(s)
Diarrhea, Infantile/prevention & control , Food, Fortified , Respiratory Tract Infections/prevention & control , Zinc/therapeutic use , Deficiency Diseases/epidemiology , Diarrhea, Infantile/epidemiology , Double-Blind Method , Female , Guatemala , Humans , Incidence , Infant , Male , Morbidity , Respiratory Tract Infections/epidemiology , Rural Population , Zinc/deficiency
10.
J Nutr ; 125(4 Suppl): 1042S-1050S, 1995 04.
Article in English | MEDLINE | ID: mdl-7722706

ABSTRACT

From 1969 to 1977 a supplementation trial was conducted in Guatemala to ascertain the effects on physical and behavioral outcomes of improved nutrition in pregnant women and in preschool children. This paper reviews different strategies to analyze the effect of the intervention on physical growth. One strategy compares outcomes in two villages that were randomly allocated to receive Atole, a supplement containing high amounts of protein and energy, with values in two other villages that received Fresco, a beverage containing no protein and little energy. Both supplements contained micronutrients. This comparison of village means gives a probability significance statement (P < 0.005) that the difference in growth was because of the supplement intervention, although it does not specify the aspect of the intervention that caused the effect. Complementary strategies increase the credibility that the effect of the supplement was nutritional. Thus, analysis of the dose response with increasing supplement intake within the villages excludes the possibility that the above findings were the result of knowing which villages received which supplement (i.e., measuring biases). A greater effect in those most likely to respond nutritionally also increases the credibility that the mechanism was nutritional. In studying other behavioral and biomedical impacts of this supplementation intervention, analyses for credibility should always be included.


Subject(s)
Child Nutrition Disorders/diet therapy , Food, Fortified , Child Nutrition Disorders/complications , Child, Preschool , Confounding Factors, Epidemiologic , Data Interpretation, Statistical , Effect Modifier, Epidemiologic , Female , Growth Disorders/prevention & control , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Pregnancy , Research Design
11.
J Nutr ; 125(4 Suppl): 1104S-1110S, 1995 04.
Article in English | MEDLINE | ID: mdl-7722713

ABSTRACT

To assess the long-term impact of nutritional supplementation on bone mineralization during adolescence, we studied 356 Guatemalan adolescents who participated from birth to 7 y of age in a controlled supplementation trial. Bone mineralization of the distal radius was assessed using single photon absorptiometry. Children who consumed more cumulative energy from the supplement during childhood had greater bone mineral content, bone width and bone mineral density during adolescence than those who consumed less energy. The associations remained after controlling for each subject's age and gender, and for the type of supplement consumed, but became statistically nonsignificant after adjusting for weight and stature. Because intake of supplement also was associated positively with weight and stature during adolescence, it is concluded that supplementing malnourished children can have a demonstrable long-term impact on bone mineralization, but that the effects are probably not beyond those due to improvements in overall somatic growth associated with supplementation.


Subject(s)
Calcification, Physiologic , Child Nutrition Disorders/diet therapy , Food, Fortified , Growth Disorders/prevention & control , Adolescent , Adult , Age Factors , Body Weight , Bone Density , Child , Child Nutrition Disorders/complications , Child, Preschool , Female , Germany , Growth Disorders/diagnostic imaging , Growth Disorders/etiology , Guatemala , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Radionuclide Imaging
12.
J Nutr ; 125(4 Suppl): 1027S-1041S, 1995 04.
Article in English | MEDLINE | ID: mdl-7536830

ABSTRACT

This is an overview of the design and methods of the INCAP longitudinal study (1969-77) and its follow-up study (1988-89). The first study had the objective of assessing the effects of intrauterine and preschool malnutrition on growth and mental development. To achieve this, food supplements were provided to pregnant women and young children residing in four Gautemalan villages. Two villages were given a high-protein, high-energy drink and two were provided a no-protein, low-energy drink. Both supplements contained vitamins and minerals. Longitudinal information was collected during the first seven years of life on physical growth, mental development, attendance and consumption of supplement, home diet, morbidity and on characteristics of the family. Health and nutrition data on mothers also were collected. The INCAP follow-up study was a cross-sectional evaluation of former participants of the first study and was carried out when the subjects were 11-27 y old. The hypothesis of the INCAP follow-up study was that improved nutrition in early childhood leads to enhanced human capital formation in adolescents and adults. Data were collected on physical growth and body composition, maturation, work capacity, intellectual performance and school achievement.


Subject(s)
Child Nutrition Disorders/diet therapy , Developmental Disabilities/prevention & control , Food, Fortified , Growth Disorders/prevention & control , Adolescent , Adult , Child , Child Nutrition Disorders/complications , Child, Preschool , Cross-Sectional Studies , Developmental Disabilities/etiology , Female , Follow-Up Studies , Food, Fortified/analysis , Growth Disorders/etiology , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Pregnancy , Research Design
13.
J Nutr ; 125(4 Suppl): 1111S-1118S, 1995 04.
Article in English | MEDLINE | ID: mdl-7536831

ABSTRACT

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.


PIP: A longitudinal study conducted during 1969-77 by the Institute of Nutrition of Central America and a cross-sectional follow-up of former participants carried out during 1988-89 investigated the effects of early supplementary feeding. The objective of these two studies was to assess the differential effect of two dietary supplements--Atole, containing 163 kcal/683 kJ and 11.5 g protein per cup or 180 ml, and Fresco, containing 59 kcal/247 kJ and 0 g protein per cup--on cognition. The dietary supplements 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. Findings revealed that subjects receiving Atole scored significantly higher on tests of knowledge, numeracy, reading, and vocabulary than those given with Fresco. Atole ingestion also was associated with faster reaction time in information processing tasks. In addition, there were significant interactions between type of dietary supplements and socioeconomic status (SES) of subjects. In Atole villages, there were no significant 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.


Subject(s)
Child Nutrition Disorders/diet therapy , Developmental Disabilities/prevention & control , Food, Fortified , Intelligence , Adolescent , Child , Child Nutrition Disorders/complications , Child Nutrition Disorders/psychology , Child, Preschool , Cross-Sectional Studies , Developmental Disabilities/etiology , Developmental Disabilities/psychology , Female , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Pregnancy , Psychological Tests , Regression Analysis
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