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In this study, we investigated the protective effect of gluta-mine on barrier dysfunction induced by ethanol, by using human epithelial colorectal adenocarcinoma cells (Caco-2). Our results show that addition of glutamine to culture me-dium significantly improved the disruption of integrity caused by ethanol, which was associated with increased ex-pression of heat shock protein 70 (Hsp70). Ethanol exposure moderately activates heat shock factor 1 (HSF1), which was characterized by increased DNA-binding activity and phos-phorylation status of HSF1. Remarkably, glutamine treat-ment enhanced ethanol-mediated expression of Hsp70 and activation of HSF1. Up-regulation of Hsp70 by pretreatment with heat stress also promoted recovery from the ethanol-induced barrier dysfunction. Taken together, these observations indicate that glutamine protects the intestinal barrier function in Caco-2 cells, in part by modulating HSF1-mediated Hsp70 expression. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are composed of multiple subsets that play a dual role in inducing immunity and tolerance. However, it is unclear how CD205+ conventional DCs (cDCs) control immune responses in vivo. Here we generated knock-in mice with the selective conditional ablation of CD205+ cDCs. CD205+ cDCs contributed to antigen-specific priming of CD4+ T cells under steady-state conditions, whereas they were dispensable for antigen-specific CD4+ T-cell responses under inflammatory conditions. In contrast, CD205+ cDCs were required for antigen-specific priming of CD8+ T cells to generate cytotoxic T lymphocytes (CTLs) mediated through cross-presentation. Although CD205+ cDCs were involved in the thymic generation of CD4+ regulatory T cells (Tregs), they maintained the homeostasis of CD4+ Tregs and CD4+ effector T cells in peripheral and mucosal tissues. On the other hand, CD205+ cDCs were involved in the inflammation triggered by Toll-like receptor ligand as well as bacterial and viral infections. Upon microbial infections, CD205+ cDCs contributed to the cross-priming of CD8+ T cells for generating antimicrobial CTLs to efficiently eliminate pathogens, whereas they suppressed antimicrobial CD4+ T-cell responses. Thus, these findings reveal a critical role for CD205+ cDCs in the regulation of T-cell immunity and homeostasis in vivo. [ABSTRACT FROM AUTHOR]

We present a case of a 46,XY der(13;14) Robertsonian translocation carrier whose spermatozoa were karyotyped after injection into mouse oocytes. Fresh semen samples as well as recovered samples were used. There was no significant difference in the survival rate of mouse oocytes (fresh: 78.1% versus frozen: 81.7%), activation rate (fresh: 84.0% versus frozen: 90.6%), fertilization rate (fresh: 72.0% versus thawing of frozen: 76.5%) between fresh or frozen spermatozoa. Metaphase chromosome spreads from 45 spermatozoa were analysed. The frequency of spermatozoa that were chromosomally unbalanced with respect to the translocation was 8.9%, and the frequency of abnormalities unrelated to translocation was 4.4%. An excess of spermatozoa with balanced chromosomes was observed: compared with normal, 23 (51.1%) versus 16 (35.6%) respectively; but this segregation difference was not statistically significant (chi(2) = 0.9, P > 0.3). After genetic counselling with the carrier and his partner, intracytoplasmic sperm injection treatment was performed. Healthy female and male infants were delivered at 36 weeks gestation via a Caesarean section. Both babies were carriers for the balanced Robertsonian translocations detected for prenatal diagnosis at 16 weeks gestation. The present study demonstrates that patients can be given further information about the proportion of the spermatozoa which carry a chromosomal abnormality. [ABSTRACT FROM AUTHOR]

In Japan and other countries where tuberculosis is not so common, people who were once infected with tuberculosis are thought to rarely suffer from the disease again due to exogenous reinfection. We experienced a mass outbreak of tuberculosis with 27 patients (including the source of infection) at a nursing home for the elderly. Epidemiological investigation suggested that the source of infection was an 82-year-old woman resident. For about 2 years before this outbreak, she had complained of a productive cough. At the time of the diagnosis of tuberculosis, chest radiography revealed a cavitary lesion and a smear of her sputum revealed organisms rated as Gaffky No. 8. Sputum culture was also positive (++++). Of the 27 patients, 19 (including the source) underwent restriction fragment length polymorphism (RFLP) analysis of isolates from the sputum. Eighteen patients showed an identical RFLP pattern, indicating that the infection had arisen from one source. Out of all patients, the source case of infection, 9 others with the same RFLP pattern, and other 3 who did not undergo RFLP analysis were admitted to our hospital. In 12 patients (3 men and 9 women excluding the source case) aged 80.6 years (range: 67-89 years), chest radiography disclosed tuberculous lesions, and smears, the polymerase chain reaction, and culture of sputum demonstrated Mycobacterium tuberculosis. As the prevalence of tuberculosis infection in Japanese aged 80 years at the time of the mass outbreak (1995) was presumed to be about 80%, the disease seemed to be caused by exogenous reinfection in most of these patients. All of the patients had senile dementia and other complications, and they were bedridden and undernourished. Anemia, hypoalbuminemia and lymphocytopenia were also observed in most of the cases. Malnutrition due to these complications appeared to be a possible risk factor of tuberculosis caused by exogenous reinfection.