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1.
Front Immunol ; 14: 1282144, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022652

RESUMO

Introduction: The gastrointestinal and immune systems of premature infants are not fully developed, rendering them more vulnerable to severe complications like necrotizing enterocolitis. Human milk offers a rich array of bioactive factors that collectively contribute to reducing the incidence of gut infections and inflammatory conditions. When a mother's milk is unavailable, preterm infants are often provided with donor human milk processed in Human Milk Banks. However, it remains uncertain whether pasteurized milk confers the same level of risk reduction as unprocessed milk. This uncertainty may stem from the well-documented adverse effects of heat treatment on milk composition. Yet, our understanding of the comprehensive impact on protective mechanisms is limited. Methods: In this study, we conducted a comparative analysis of the effects of raw versus pasteurized milk and colostrum versus mature milk on cellular functions associated with the gut epithelial barrier and responses to inflammatory stimuli. We utilized THP-1 and HT-29 cell lines, representing monocyte/macrophages and gut epithelial cells, respectively. Results: Our observations revealed that all milk types stimulated epithelial cell proliferation. However, only raw colostrum increased cell migration and interfered with the interaction between E. coli and epithelial cells. Furthermore, the response of epithelial and macrophage cells to lipopolysaccharide (LPS) was enhanced solely by raw colostrum, with a milder effect observed with mature milk. In contrast, both raw and pasteurized milk diminished the LPS induced response in monocytes. Lastly, we examined how milk affected the differentiation of monocytes into macrophages, finding that milk reduced the subsequent inflammatory response of macrophages to LPS. Discussion: Our study sheds light on the impact of human milk on certain mechanisms that potentially account for its protective effects against necrotizing enterocolitis, highlighting the detrimental influence of pasteurization on some of these mechanisms. Our findings emphasize the urgency of developing alternative pasteurization methods to better preserve milk properties. Moreover, identifying the key components critically affected by these protective mechanisms could enable their inclusion in donor milk or formula, thereby enhancing immunological benefits for vulnerable newborns.


Assuntos
Enterocolite Necrosante , Leite Humano , Lactente , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Enterocolite Necrosante/prevenção & controle , Enterocolite Necrosante/epidemiologia , Lipopolissacarídeos , Escherichia coli , Inflamação
4.
J Hum Lact ; 34(1): 137-147, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28586632

RESUMO

BACKGROUND: When feeding preterm infants, donor milk is preferred if the mother's own milk is unavailable. Pasteurization may have detrimental effects on bioactivity, but more information is needed about its effects on the immunological compounds. Research aim: This work has two main aims: evaluate the antibody profile of colostrum and study the quantitative variations in the antibodies' level and specific reactivity after undergoing Holder pasteurization. The authors focused on immunoregulatory components of colostrum (antidietary antibodies and TGF-ß2) in the neonatal gut. METHODS: This is a descriptive cross-sectional study of a convenience sample of 67 donated colostrum samples at different days after delivery, both raw and pasteurized. Antibody profiles were analyzed at different times during breastfeeding, and total and specific antibodies (IgM, IgA, and IgG subclasses) were compared with tetanus toxoid and ovalbumin using enzyme-linked immunosorbent assay. The processing effect on total and specific antibodies, as well as TGF-ß2, was evaluated by paired analyses. RESULTS: No variations in immunological compounds were observed throughout the colostrum stage. The TGF-ß2, antibodies' concentrations, and antibodies' specific reactivity after pasteurization did not vary significantly as days of lactation varied. Changes in antibody levels were dependent on isotype and IgG subclass, and IgG4 showed remarkable resistance to heating. Moreover, the effect of the pasteurization on specific reactivity was antigen dependent. CONCLUSION: The supply of relevant immunological components is stable throughout the colostrum stage. The effects of pasteurization on antibodies depend on isotype, subclass, and specificity. This information is relevant to improving the immunological quality of colostrum, especially for preterm newborns.


Assuntos
Colostro/imunologia , Leite Humano/imunologia , Pasteurização/estatística & dados numéricos , Colostro/química , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Bancos de Leite Humano/organização & administração , Leite Humano/química , Pasteurização/métodos , Pasteurização/normas , Estatísticas não Paramétricas , Uruguai
5.
Arch. pediatr. Urug ; 87(4): 347-350, dic. 2016. tab
Artigo em Espanhol | LILACS | ID: biblio-827821

RESUMO

En los últimos años se ha observado un aumento en la incidencia de Campylobacter spp (CSSP) como agente de diarrea, enteritis y disentería. Constituye una zoonosis así como una enfermedad trasmitida por alimentos. El diagnóstico de GEA por CSPP se realiza por identificación del agente etiológico en las heces del paciente. El objetivo de la siguiente observación es presentar dos casos clínicos de GEA en niños con diagnóstico etiológico de colitis causada probablemente por Campylobacter spp mediante la utilización de examen directo de materia fecal. El cultivo de la bacteria es el gold standard; en Uruguay sólo está disponible con fines de investigación. El método más fácil de poner en práctica en los laboratorios clínicos es la tinción y observación directa con un Gram modificado el cual sumado a la clínica, permite un diagnóstico con alto grado de presunción. En ambos pacientes el resultado motivó la instauración de un tratamiento antibiótico específico que determinó una buena evolución.


In recent years an increase in the incidence of Campylobacter spp (CSSP) as the agent of diarrhea, enteritis and dysentery was observed. It constitutes a zoonosis, as well as a food transmitted disease. Diagnosis of acute gastroenteritis by CSPP is done by identifying the etiological agent on the patients’ feces. The objective of the following observation is to present two clinical cases of acute gastroenteritis in children with an etiological diagnosis of colitis, probably caused by Campylobacter spp by means of a direct study of the stool. Culture of the bacteria is the gold standard, although in Uruguay it is only available for research purposes. The easiest method to put into practice in the clinical laboratories is staining and the direct observation with a modified Gram, which, together with the clinical examination, enables diagnosis with a high degree of presumption. In both patients, the result caused the adoption of a specific antibiotic, which determined a good evolution.


Assuntos
Humanos , Masculino , Lactente , Criança , Infecções por Campylobacter , Infecções por Campylobacter/complicações , Infecções por Campylobacter/diagnóstico , Técnicas e Procedimentos Diagnósticos , Disenteria/etiologia , Gastroenterite/etiologia , Campylobacter/patogenicidade
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