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1.
EBioMedicine ; 75: 103791, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35030356

RESUMO

BACKGROUND: Kwashiorkor is a childhood syndrome of edematous malnutrition. Its precise nutritional precipitants remain uncertain despite nine decades of study. Remarkably, kwashiorkor's disturbances resemble the effects of experimental diets that are deficient in one-carbon nutrients. This similarity suggests that kwashiorkor may represent a nutritionally mediated syndrome of acute one-carbon metabolism dysfunction. Here we report findings from a cross-sectional exploration of serum one-carbon metabolites in Malawian children. METHODS: Blood was collected from children aged 12-60 months before nutritional rehabilitation: kwashiorkor (N = 94), marasmic-kwashiorkor (N = 43) marasmus (N = 118), moderate acute malnutrition (N = 56) and controls (N = 46). Serum concentrations of 16 one-carbon metabolites were quantified using LC/MS techniques, and then compared across participant groups. FINDINGS: Twelve of 16 measured one-carbon metabolites differed significantly between participant groups. Measured outputs of one-carbon metabolism, asymmetric dimethylarginine (ADMA) and cysteine, were lower in marasmic-kwashiorkor (median µmol/L (± SD): 0·549 (± 0·217) P = 0·00045 & 90 (± 40) P < 0·0001, respectively) and kwashiorkor (0·557 (± 0·195) P < 0·0001 & 115 (± 50) P < 0·0001), relative to marasmus (0·698 (± 0·212) & 153 (± 42)). ADMA and cysteine were well correlated with methionine in both kwashiorkor and marasmic-kwashiorkor. INTERPRETATION: Kwashiorkor and marasmic-kwashiorkor were distinguished by evidence of one-carbon metabolism dysfunction. Correlative observations suggest that methionine deficiency drives this dysfunction, which is implicated in the syndrome's pathogenesis. The hypothesis that kwashiorkor can be prevented by fortifying low quality diets with methionine, along with nutrients that support efficient methionine use, such as choline, requires further investigation. FUNDING: The Hickey Family Foundation, the American College of Gastroenterology, the NICHD, and the USDA/ARS.


Assuntos
Kwashiorkor , Desnutrição , Desnutrição Proteico-Calórica , Carbono , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Kwashiorkor/etiologia , Kwashiorkor/metabolismo , Desnutrição Proteico-Calórica/metabolismo
2.
Am J Gastroenterol ; 114(4): 671-678, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30829679

RESUMO

INTRODUCTION: Environmental enteric dysfunction (EED) predisposes children throughout the developing world to high rates of systemic exposure to enteric pathogens and stunting. Effective interventions that treat or prevent EED may help children achieve their full physical and cognitive potential. The objective of this study is to test whether 2 components of breast milk would improve a biomarker of EED and linear growth during the second year of life. METHODS: A prospective, randomized, double-blind, placebo-controlled clinical trial among children aged 12-23 months was conducted in rural Malawi. The experimental group received a daily supplement of 1.5 g of lactoferrin and 0.2 g of lysozyme for 16 weeks. The primary outcome was an improvement in EED, as measured by the change in the percentage of ingested lactulose excreted into the urine (Δ%L). RESULTS: Among 214 children who completed the study, there was a significant difference in Δ%L between the control and experimental groups over 8 weeks (an increase of 0.23% vs 0.14%, respectively; P = 0.04). However, this relative improvement was not as strongly sustained over the full 16 weeks of the study (an increase of 0.16% vs 0.11%, respectively; P = 0.17). No difference in linear growth over this short period was observed. The experimental intervention group had significantly lower rates of hospitalization and the development of acute malnutrition during the course of the study (2.5% vs 10.3%, relative risk 0.25; P < 0.02). DISCUSSION: Supplementation with lactoferrin and lysozyme in a population of agrarian children during the second year of life has a beneficial effect on gut health. This intervention also protected against hospitalization and the development of acute malnutrition, a finding with a significant clinical and public health importance. This finding should be pursued in larger studies with longer follow-up and optimized dosing.


Assuntos
Transtornos do Crescimento/prevenção & controle , Transtornos da Nutrição do Lactente/tratamento farmacológico , Lactoferrina/uso terapêutico , Desnutrição/tratamento farmacológico , Muramidase/uso terapêutico , Espru Tropical/tratamento farmacológico , Desenvolvimento Infantil , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Malaui , Masculino , Estudos Prospectivos
3.
Analyst ; 144(6): 2026-2033, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30702091

RESUMO

In this report, we present a post hoc analysis from two observational cohorts, comparing the global breath volatile profile captured when using polymer sampling bags (mixed breath) versus Bio-VOC™ (alveolar breath). The cohorts were originally designed to characterize the breath volatile profiles of Malawian children with and without uncomplicated falciparum malaria. Children aged 3-15 years were recruited from ambulatory pediatric centers in Lilongwe, Malawi. Breath sampling was carried out two months apart (one study using a Bio-VOC™ and the second using sampling bags), and all samples were analyzed by gas chromatography/mass spectrometry. The efficacy of breath collection was assessed by quantifying levels of two high prevalence breath compounds, acetone and isoprene, as well as determining the overall number of breath compounds collected and their abundance. We found that the mean number of volatiles detected using sampling bags was substantially higher than when using the Bio-VOC™ (137 vs. 47). Breath collection by Bio-VOC™ also yielded reduced levels of endogenous breath volatiles, isoprene and acetone, even after breath volume correction. This suggests that the Bio-VOC™ dilutes the volatiles and introduces dead air or ambient air. Our results suggest that sampling bags are better suited for biomarker discovery and untargeted search of volatiles in pediatric populations, as evidenced by superior breath volatile detection.


Assuntos
Biomarcadores/análise , Testes Respiratórios/métodos , Malária Falciparum/diagnóstico , Plasmodium falciparum/isolamento & purificação , Polímeros/química , Compostos Orgânicos Voláteis/análise , Adolescente , Butadienos/análise , Criança , Pré-Escolar , Estudos de Coortes , Cromatografia Gasosa-Espectrometria de Massas , Hemiterpenos/análise , Humanos
4.
J Infect Dis ; 217(10): 1553-1560, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29415208

RESUMO

Current evidence suggests that malarial infection could alter metabolites in the breath of patients, a phenomenon that could be exploited to create a breath-based diagnostic test. However, no study has explored this in a clinical setting. To investigate whether natural human malarial infection leads to a characteristic breath profile, we performed a field study in Malawi. Breath volatiles from children with and those without uncomplicated falciparum malaria were analyzed by thermal desorption-gas chromatography/mass spectrometry. Using an unbiased, correlation-based analysis, we found that children with malaria have a distinct shift in overall breath composition. Highly accurate classification of infection status was achieved with a suite of 6 compounds. In addition, we found that infection correlates with significantly higher breath levels of 2 mosquito-attractant terpenes, α-pinene and 3-carene. These findings attest to the viability of breath analysis for malaria diagnosis, identify candidate biomarkers, and identify plausible chemical mediators for increased mosquito attraction to patients infected with malaria parasites.


Assuntos
Anopheles/patogenicidade , Biomarcadores/química , Biomarcadores/metabolismo , Malária Falciparum/diagnóstico , Malária Falciparum/metabolismo , Odorantes/análise , Compostos Orgânicos Voláteis/química , Animais , Testes Respiratórios/métodos , Criança , Pré-Escolar , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Malária Falciparum/parasitologia , Malaui , Masculino , Plasmodium falciparum/patogenicidade
5.
Am J Clin Nutr ; 106(2): 657-666, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28615258

RESUMO

Background: Children who recover from moderate acute malnutrition (MAM) have high rates of relapse in the year after nutritional recovery. Interventions to decrease these adverse outcomes are needed to maximize the overall effectiveness of supplemental feeding programs (SFPs).Objective: We evaluated the effectiveness of a package of health and nutrition interventions on improving the proportion of children who sustained recovery for 1 y after MAM treatment. We further explored factors related to sustained recovery.Design: We conducted a cluster-randomized clinical effectiveness trial involving rural Malawian children aged 6-62 mo who were enrolled on discharge from an SFP for MAM. We enrolled 718 children at 10 control sites and 769 children at 11 intervention sites. In addition to routine health and nutrition counseling, the intervention group received a package of health and nutrition interventions that consisted of a lipid nutrient supplement, deworming medication, zinc supplementation, a bed net, and malaria chemoprophylaxis. A survival analysis was used to determine the effectiveness of the intervention as well as to identify factors associated with sustained recovery.Results: Of 1383 children who returned for the full 12-mo follow-up period, 407 children (56%) and 347 children (53%) sustained recovery in the intervention and control groups, respectively. There was no significant difference in relapse-free survival curves between the treatment and control groups (P = 0.380; log-rank test). The risk factors for relapse or death after initial recovery were a smaller midupper arm circumference on SFP admission (P = 0.01) and discharge (P < 0.001), a lower weight-for-height z score on discharge (P < 0.01), and the receipt of ready-to-use supplementary food as opposed to ready-to-use therapeutic food during treatment (P < 0.05).Conclusion: The provision of a package of health and nutrition services in addition to traditional SFP treatment has no significant effect on improving sustained recovery in children after treatment of MAM. This trial was registered at clinicaltrials.gov as NCT02351687.


Assuntos
Transtornos da Nutrição Infantil/terapia , Suplementos Nutricionais , Alimentos Formulados , Alimentos Fortificados , Serviços de Saúde , Desnutrição/terapia , Estado Nutricional , Criança , Transtornos da Nutrição Infantil/dietoterapia , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Lipídeos/uso terapêutico , Malária/prevenção & controle , Malaui , Masculino , Desnutrição/dietoterapia , Doenças Parasitárias/prevenção & controle , Recidiva , População Rural , Aumento de Peso , Zinco/uso terapêutico
6.
Nutrients ; 8(10)2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27690090

RESUMO

Globally, childhood undernutrition continues to be a major public health concern, with an estimated 165 million children classified as stunted and 51.5 million suffering from acute malnutrition.[...].

7.
Trials ; 16: 520, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26578308

RESUMO

BACKGROUND: Interventions to decrease the burden of childhood malnutrition are urgently needed, as millions of children die annually owing to undernutrition and hundreds of millions more are left cognitively and physically stunted. Environmental enteric dysfunction (EED), a pervasive chronic subclinical inflammatory condition among children that develops when complementary foods are introduced, places them at high risk of stunting, malabsorption, and poor oral vaccine efficacy. Improved interventions to reduce the burden of EED and stunting are expected to markedly improve the nutritional status and survival of children throughout resource-limited settings. METHODS/DESIGN: We will conduct, in parallel, two prospective randomized controlled clinical trials to determine whether common beans or cowpeas improve growth, ameliorate EED, and alter the intestinal microbiome during a high-risk period in the lives of rural Malawian children. Study 1 will enroll children at 6 months of age and randomize them to receive common beans, cowpeas, or a standard complementary food for 6 months. Anthropometry will be compared among the three groups; EED will be assessed using a dual-sugar absorption test and by quantifying human intestinal mRNA for inflammatory messages; and the intestinal microbiota will be characterized by deep sequencing of fecal DNA, to enumerate host microbial populations and their metabolic capacity. Study 2 will enroll children 12-23 months old and follow them for 12 months, with similar interventions and assessments as Study 1. DISCUSSION: By amalgamating the power of rigorous clinical trials and advanced biological analysis, we aim to elucidate the potential of two grain legumes to reduce stunting and EED in a high-risk population. Legumes have potential as an affordable and effective complementary food intervention, given their cultural acceptability, nutritional content, and agricultural feasibility in sub-Saharan Africa. TRIAL REGISTRATION: Clinicaltrials.gov NCT02472262 and NCT02472301 .


Assuntos
Dieta , Meio Ambiente , Fabaceae , Transtornos do Crescimento/prevenção & controle , Enteropatias/prevenção & controle , Intestinos/fisiopatologia , Síndromes de Malabsorção/prevenção & controle , Phaseolus , Desenvolvimento Infantil , Microbioma Gastrointestinal , Transtornos do Crescimento/diagnóstico , Transtornos do Crescimento/microbiologia , Transtornos do Crescimento/fisiopatologia , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Enteropatias/diagnóstico , Enteropatias/microbiologia , Enteropatias/fisiopatologia , Intestinos/microbiologia , Síndromes de Malabsorção/diagnóstico , Síndromes de Malabsorção/microbiologia , Síndromes de Malabsorção/fisiopatologia , Malaui , Avaliação Nutricional , Estado Nutricional , Estudos Prospectivos , Projetos de Pesquisa , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
8.
Antimicrob Agents Chemother ; 57(8): 3645-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23689713

RESUMO

Antivirulence agents inhibit the production of disease-causing virulence factors but are neither bacteriostatic nor bactericidal. Antivirulence agents against methicillin-resistant Staphylococcus aureus (MRSA) strain USA300, the most widespread community-associated MRSA strain in the United States, were discovered by virtual screening against the response regulator AgrA, which acts as a transcription factor for the expression of several of the most prominent S. aureus toxins and virulence factors involved in pathogenesis. Virtual screening was followed by similarity searches in the databases of commercial vendors. The small-molecule compounds discovered inhibit the production of the toxins alpha-hemolysin and phenol-soluble modulin α in a dose-dependent manner without inhibiting bacterial growth. These antivirulence agents are small-molecule biaryl compounds in which the aromatic rings either are fused or are separated by a short linker. One of these compounds is the FDA-approved nonsteroidal anti-inflammatory drug diflunisal. This represents a new use for an old drug. Antivirulence agents might be useful in prophylaxis and as adjuvants in antibiotic therapy for MRSA infections.


Assuntos
Toxinas Bacterianas/antagonistas & inibidores , Diflunisal/farmacologia , Proteínas Hemolisinas/antagonistas & inibidores , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fatores de Virulência/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Hemólise , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Modelos Moleculares , Naftalenos/química , Naftalenos/farmacologia , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Estrutura Terciária de Proteína , Coelhos , Transcrição Gênica
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