Goat milk with and without increased concentrations of lysozyme improves repair of intestinal cell damage induced by enteroaggregative Escherichia coli.

BACKGROUND: Enteroaggregative Escherichia coli (EAEC) causes diarrhea, malnutrition and poor growth in children. Human breast milk decreases disease-causing bacteria by supplying nutrients and antimicrobial factors such as lysozyme. Goat milk with and without human lysozyme (HLZ) may improve the repair of intestinal barrier function damage induced by EAEC. This work investigates the effect of the milks on intestinal barrier function repair, bacterial adherence in Caco-2 and HEp-2 cells, intestinal cell proliferation, migration, viability and apoptosis in IEC-6 cells in the absence or presence of EAEC. METHODS: Rat intestinal epithelial cells (IEC-6, ATCC, Rockville, MD) were used for proliferation, migration and viability assays and human colon adenocarcinoma (Caco-2, ATCC, Rockville, MD) and human larynx carcinoma (HEp-2, ATCC, Rockville, MD) cells were used for bacterial adhesion assays. Goats expressing HLZ in their milk were generated and express HLZ in milk at concentration of 270 µg/ml. Cells were incubated with pasteurized milk from either transgenic goats expressing HLZ or non-transgenic control goats in the presence and absence of EAEC strain 042 (O44:H18). RESULTS: Cellular proliferation was significantly greater in the presence of both HLZ transgenic and control goat milk compared to cells with no milk. Cellular migration was significantly decreased in the presence of EAEC alone but was restored in the presence of milk. Milk from HLZ transgenic goats had significantly more migration compared to control milk. Both milks significantly reduced EAEC adhesion to Caco-2 cells and transgenic milk resulted in less colonization than control milk using a HEp-2 assay. Both milks had significantly increased cellular viability as well as less apoptosis in both the absence and presence of EAEC. CONCLUSIONS: These data demonstrated that goat milk is able to repair intestinal barrier function damage induced by EAEC and that goat milk with a higher concentration of lysozyme offers additional protection.

Role of retinol in protecting epithelial cell damage induced by Clostridium difficile toxin A.

Vitamin A (retinol), a fat-soluble vitamin, is an essential nutrient for the normal functioning of the visual system, epithelial cell integrity and growth, immunity, and reproduction. Our group has investigated the effect of high doses of oral vitamin A on early childhood diarrhea in our prospective community-based studies from Northeast Brazil and found a beneficial role in reducing the mean duration but not incidence of diarrheal episodes. In this study, we explored the role of retinol supplementation in intestinal cell lines following Clostridium difficile toxin A (TxA) challenge. C. difficile is the most common anaerobic pathogen borne with antibiotic-borne diarrhea and pseudomembranous colitis. Since retinol is critical for the integrity of tight junctions and to modulate the cell cycle, we have focused on changes in transepithelial electrical resistance (TEER) in Caco-2, a more differentiated intestinal cell line, and on models of cell proliferation, migration and viability in IEC-6 cells, an undifferentiated crypt cell line, following TxA injury. In this model, retinol therapy reduced apoptosis, improved cell migration and proliferation, and prevented the reduction in TEER, following C. difficile TxA challenge in a glutamine-free medium. These results suggest the role of retinol in protecting intestinal epithelial barrier function from C. difficile TxA enterotoxic damage.

Efeito da bomba de infusão de soluções sobre o grau de hemólise em concentrados de hemácias / Effect of the infusion pumps of solutions on the degree of hemolysis

A lise das hemácias, de causa imune ou não imune, pode provocar a elevação da hemoglobina plasmática induzindo efeitos deletérios principalmente nos rins e no sistema cardiovascular. Este trabalho objetiva evidenciar o possível efeito hemolítico induzido pelo trauma mecânico provocado pela passagem das hemácias em diferentes modelos de bombas de infusão de soluções, em concentrados de hemácias com até dez dias de armazenamento, preparados com Sag-Manitol. Foram utilizados três modelos de bombas (Nutrimat, Infusomat Compact e Volumed), com quatro aparelhos de cada modelo, testados em três velocidades de infusão (120 mL/h, 240 mL/h e 360 mL/h). Os parâmetros utilizados para evidenciar o grau de hemólise foram o percentual de hemólise e os níveis de hemoglobina e potássio livres no plasma. As amostras foram coletadas antes da passagem do concentrado de hemácias pelas bombas, na metade do tempo de infusão e no final da infusão, nas diferentes velocidades. Não ocorreu variação significativa entre os valores dos parâmetros analisados nas amostras controle e naquelas coletadas nas diferentes velocidades, marcas de bombas, mecanismos de infusão entre as bombas da mesma marca e entre os diferentes tempos de infusão. A principal variação encontrada foi relacionada com o potássio livre, devido à variação inerente aos próprios concentrados, o que foi evidenciado ao se compararem os valores obtidos nas amostras controle e nas amostras colhidas nos tempos médio e final em cada bomba. De acordo com os resultados obtidos, não houve alteração estatisticamente significativa do percentual de hemólise após a passagem pelas bombas de infusão nos modelos analisados.

The lyses of red blood cells, both for immune or non-immune reasons, can cause an elevation in plasmatic hemoglobin, inducing harmful effects mainly in the kidneys and cardiovascular system. This work aims at identifying the possible hemolytic effect, related to mechanical trauma due to the use of different models of infusion pumps, on red blood cells transfused after up to ten days of storage. Three models of pumps were studied (Nutrimat, Infusomat Compact and Volumed), (four devices of each model) with three infusion speeds being tested (120 mL/h, 240 mL/h and 360 mL/h). The parameters used to report the degree of hemolysis were the percentile of hemolysis, hemoglobin levels and free potassium in the plasma. Samples were collected before infusion of red blood cells using the pumps, half way through infusion (1/2 T) and at the end of infusion (T), for the three different speeds. Significant variations were not seen in the analyzed parameters between the control samples and those collected at different speeds, using different models of pumps and infusion mechanisms and among pumps of the same brand and at different infusion times. The greatest variation found involved free potassium, probably due to the different levels found in red blood cell concentrates seen when control samples were compared to values obtained half way through and at the end of infusion for each pump. In agreement with the obtained results changes in the percentile of hemolysis were not found after infusion of the cells using the different infusion pumps.

Rastreamento familiar do fator V de Leiden: a importância da deteccão de portadores heterozigotos / Familiar tracking of factor V Leiden: the importance of detection in heterozygous carriers

O fator de Leiden é uma mutacão genética que predispõe seus portadores ao tromboembolismo venoso. O objetivo do estudo foi investigar a distribuicão dos alelos em 21 membros da família de três pacientes portadores de trombose com a presenca da mutacão do fator V de Leiden. A deteccão da mutacão no gene do fator V foi realizada entre portadores da mutacão no estado heterozigoto. Este estudo foi realizado no Centro de Hematologia e Hemoterapia do Ceará - Hemoce. Observou-se a presenca da mutacão no estado heterozigoto na família 1 (83,3 por cento), na família 2 (40 por cento) e na família 3 (50 por cento). No total de 24 membros (pacientes e familiares) analisados, 50 por cento (12/24) apresentaram a mutacão, todos no estado heterozigoto, 66,7 por cento (8/12) não apresentaram trombose. A deteccão do fator V de Leiden em pacientes portadores de eventos trombóticos é recomendado para esclarecimento das causas e para efetuar o rastreamento em membros de sua família, ainda sem o aparecimento de eventos trombóticos, de forma a avaliar os riscos associados e assim determinar um acompanhamento médico preventivo.