RESUMEN
The disruption of the natural flora of the gastrointestinal tract (especially Lactobacillus acidophilus) may occur during antibiotic therapy. This may lead to diarrhea, dehydration, and electrolyte imbalances. It has been suggested that replacement of the lactobacilli with a commercially available product may prevent the diarrhea. The efficacy and safety of prophylactically administered Lactinex (culture of L. acidophilus and L. bulgaricus) was compared with placebo for the prevention of amoxicillin-induced diarrhea in pediatric patients. Lactinex or placebo was administered four times a day for ten days to coincide with the antibiotic therapy. The Lactobacillus preparation did not appear to consistently prevent diarrhea in this patient population. Patients' age, diet, and parental definition of diarrhea were factors that may have influenced the results.
Asunto(s)
Amoxicilina/efectos adversos , Productos Biológicos/uso terapéutico , Diarrea/prevención & control , Productos Biológicos/efectos adversos , Preescolar , Diarrea/inducido químicamente , Diarrea/microbiología , Método Doble Ciego , Humanos , Lactante , Lactobacillus acidophilus/efectos de los fármacos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Previous studies on the genome of Strongylocentrotus purpuratus sea urchin have shown that changes in the nucleotide sequence of inverted repeat sequences occur during embryogenesis. The present study indicates that these sequence changes fail to occur when the embryos are raised in the presence of 5-bromodeoxyuridine. This drug is an analog of thymidine, is incorporated into the DNA during embryogenesis, and inhibits cell differentiation in these embryos.
Asunto(s)
Secuencia de Bases/efectos de los fármacos , Bromodesoxiuridina/farmacología , Replicación del ADN/efectos de los fármacos , Óvulo/metabolismo , Animales , Femenino , Erizos de MarRESUMEN
Hairpin-like DNA was prepared in vitro from the family of sequences that are inverted relative to each other and, as pairs, are relatively homologous and adjacent on the sea urchin genome. The majority of these hairpins are shown to have base pair mismatch positions distributed along their stems. Comparison of the hairpins derived from the DNA of morula, blastula, and gastrula stage embryos shows that during embryogenesis there are changes in the average number and position of S1 nuclease-sensitive base pair mismatch sites on the majority of the hairpin stems. Our data indicate that during early embryogenesis there are sequence changes in vivo within the majority of the adjacent inverted repeat sequences of the sea urchin genome. We have also found that there is higher specificity for the occurrence of sequence-change events within that fraction of the inverted repeat sequences that are methylated in vivo.