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The intestinal epithelium is a monolayer of cells arranged side‑by‑side and connected by tight junction (TJ) proteins expressed at the apical extreme of the paracellular membrane. This layer prevents stress‑induced inflammatory responses, thus helping to maintain gut barrier function and gut homeostasis. The aim of the present study was to evaluate the effects of chronic immobilization stress on the colonic expression of various parameters of homeostasis. A total of two groups of female BALB/c mice (n=6) were included: A stressed group (short‑term immobilization for 2 h/day for 4 consecutive days) and an unstressed (control) group. Colon samples were obtained to detect neutrophils and goblet cells by optical microscopy, TJ protein expression (occludin, and claudin ‑2, ‑4, ‑7, ‑12 and ‑15) by western blotting, mRNA levels of TJ genes and proinflammatory cytokines [tumor necrosis factor (TNF)‑α, interleukin (IL)‑1β, ‑6 and ‑8] by reverse transcription‑quantitative PCR, fecal lactoferrin by ELISA and the number of colony‑forming units of aerobic bacteria. Compared with goblet cells in control mice, goblet cells were enlarged and reduced in number in stressed mice, whereas neutrophil cellularity was unaltered. Stressed mice exhibited reduced mRNA expression for all evaluated TJ mRNAs, with the exception of claudin‑7, which was upregulated. Protein levels of occludin and all claudins (with the exception of claudin‑12) were decreased in stressed mice. Fecal lactoferrin, proinflammatory cytokine mRNA levels and aerobic bacterial counts were all increased in the stressed group. These results indicated that immobilization stress induced proinflammatory and potential remodeling effects in the colon by decreasing TJ protein expression. The present study may be a useful reference for therapies aiming to regulate the effects of stress on intestinal inflammatory dysfunction.

BACKGROUND: Enterococci are lactic acid bacteria that can produce bacteriocins, which may offer an additional hurdle to control the growth of food-borne pathogens; moreover, these bacteriocins may have great potential as natural biopreservatives. The aim of this work was to characterize a bacteriocin-like inhibitory substance (BLIS) with antilisterial activity produced by an enterococcal strain. RESULTS: The bacteriogenic strain was isolated from Mexican fermented sausages and identified as Enterococcus faecium with 99% sequence similarity. Maximal activity was detected at 16 h, where bacterial growth was in middle of the stationary phase. The producer strain was not inhibited by its own antimicrobial peptide. BLIS showed a strong anti-Listeria activity and was inactivated by proteinase K. Heating (121 ◦ C for 15 min) induced some inactivation, but thermotolerance was higher at acid pH values. The yield obtained with a pH-mediated purification process was 32.7%, showing a band with an estimated molecular weight of 3.5 kDa. Automated N-terminal Edman degradation showed the following sequence: YYGNGVTCGSHHCSVD. CONCLUSION: Biochemical characteristics of BLIS produced by E. faecium MXVK29 suggested that it belongs to Class IIa of the Klaenhammer classification and could be considered as a natural food preservative, although further studies need to be performed. c � 2010 Society of Chemical Industry

Urinary tract infections (UTIs) are widely extended among ambulatory and hospitalized patients under psychiatric treatment in all around the world in developed and developing countries. There are few reports about UTIs in this special type of patients, most of them are hospital inpatients and stay for very long periods of time, while others are hospitalized and discharged several times during years of treatment as their illness evolves. Several factors associated to UTIs including age, gender, type of psychiatric disease, use of invasive devices such as catheter, and recently genetic background has been considered. Despite innate mechanical safeguards against microbial infection of the intact human urinary tract, specific organisms are capable of colonizing and persisting in this environmental niche. Most infections in the urinary tract are caused by Gram negative including uropathogenic Escherichia coli (UPEC) and Proteus mirabilis, and Gram positive bacteria such as Staphyloccous aureus carrying a wide array of virulence factors. A main concern of the frequent antibiotic treatment prescribed for the therapy to combat UTIs is the growing generation of bacterial resistance. Application of antimicrobial agents for treatment of UTIs produces clinically relevant adverse reaction because of their interactions with psychotropic drugs prescribed to psychiatric patients. The pharmaceutical surveillance for tracking adverse reactions represents the main goal in the prevention and control of UTIs in psychiatric patients. In spite of pathogenic protozoa like Thrichomonas vaginalis and yeasts such as Candida albicans are usually associated to UTIs this chapter is focused on the bacterial pathogens. Therefore this work reviews the UTIs associated to bacteria in psychiatric patients, a group scarcely analyzed in spite of their clinical relevance. The scope of this study is to contribute on the understanding of the treatment for UTIs to prevent their spreading among patients and the medical care workers, due to their special conditions.

Secretory and systemic antibody response in mice against enteropathogenic Escherichia coli (EPEC) was evaluated. Groups of mice were immunized with formalin inactivated EPEC 0127:H6 strain by intranasal, peroral, intragastric and intrarectal route, with and without cholera toxin (CT) used as mucosal adjuvant. Mice immunized subcutaneously and a non treated control group were included. Other groups of mice were immunized intranasally with different EPEC strains and a non pathogenic E. coli K12 strain. Antibody response tested by ELISA assay showed that specific anti EPEC 0127:H6 antibodies were induced in serum by intranasal, subcutaneous and intragastric routes. A strong increase of antibody response against EPEC 0127:H6 strain was observed in saliva after intranasal delivery, while a lower response was detected by peroral and intrarectal immunization. Only the intranasal route increased IgA anti EPEC 0127:H6 antibody titers in feces. Specific and cross reactive antibodies to EPEC 0127:H6 were seen in mice immunized intranasally with different EPEC strains. Some control mice showed a background of anti EPEC 0127:H6 antibodies in feces. CT had a negative effect as adjuvant. We showed that nasal mucosa rendered the strongest antibody response in serum and secretions. These results might contribute to optimize the protective effect of enteric vaccines against infections associated to EPEC.

muchas clases de plantas contienen fitoquímicos que se caracterizan por ser componentes bioactivos que exhiben propiedades farmacológicas. Algunos fitoquímicos están presentes en alimentos funcionales de vegetales comestibles. Los alimentos funcionales de origen vegetal son componentes usuales de la dieta que además de exhibir propiedades nutritivas poseen efectos terapéuticos asociados a su contenido de fitoquímicos. Los fitoquímicos presentes en alimentos funcionales de origen vegetal son de especial interés en la industria farmacéutica para la obtención de fármacos inocuos y efectivos para el tratamiento de diversas enfermedades. La aplicación racional de componentes bioactivos de plantas comestibles como fármacos demanda un conocimiento profundo de sus propiedades farmacológicas para estimar sus efectos terapéuticos y potencial toxicidad.