Escherichia coli translocation in experimental short bowel syndrome: probiotic supplementation and detection by polymerase chain reaction.

BACKGROUND: After massive bowel resection, bacterial overgrowth is frequent and favors the occurrence of Gram-negative intestinal bacterial translocation (BT). Probiotics have been recommended in several diseases and may also have beneficial effects on BT. Conversely, polymerase chain reaction (PCR) technique has shown better sensitivity than conventional methods in bacterial detection and has not been investigated in experimental models of short bowel syndrome and BT. OBJECTIVE: To test the hypothesis that Bifidobacterium lactis (BL) administration decreases Escherichia coli bacterial translocation (ECBT) in experimental short bowel syndrome and to confirm the better sensitivity of PCR technique to detect ECBT. METHODS: Forty-eight adult Wistar rats, orally fed with standard rat chow and tap water ad libitum, were maintained in individual metabolic cages for 10 days and divided into three groups: Control group (n = 15): non-manipulated animals. RES group (n = 15): 80% gut resection. 1 ml of sterile water was administered daily after orogastric intubation. RES-PRO group (n = 18): same resection as RES group and daily administration of 7.8 × 10(9) BL (CFU). At the end of the study, portal blood, peripheral blood and mesenteric lymph node (MLN) samples were recovered and cultured. Also, genomic DNA from E. coli was detected by PCR technique. RESULTS: In conventional culture there was no ECBT in control animals whereas 73% of RES and 33% of RES-PRO animals showed it. PCR detected ECBT in 47, 87 and 33%, respectively, showing higher sensitivity.

Age-dependent depletion of human skin-derived progenitor cells.

A major unanswered question in autologous cell therapy is the appropriate timing for cell isolation. Many of the putative target diseases arise with old age and previous evidence, mainly from animal models, suggests that the stem/progenitor cell pool decreases steadily with age. Studies with human cells have been generally hampered to date by poor sample availability. In recent years, several laboratories have reported on the existence, both in rodents and humans, of skin-derived precursor (SKP) cells with the capacity to generate neural and mesodermal progenies. This easily obtainable multipotent cell population has raised expectations for their potential use in cell therapy of neurodegeneration. However, we still lack a clear understanding of the spatiotemporal abundance and phenotype of human SKPs. Here we show an analysis of human SKP abundance and in vitro differentiation potential, by using SKPs isolated from four distinct anatomic sites (abdomen, breast, foreskin, and scalp) from 102 healthy subjects aged 8 months to 85 years. Human SKP abundance and differentiation potential decrease sharply with age, being extremely difficult to isolate, expand, and differentiate when obtained from the elderly. Our data suggest preserving human SKP cell banks early in life would be desirable for use in clinical protocols in the aging population.