Protective effects of ascorbic acid on hepatotoxicity and oxidative stress caused by carbon tetrachloride in the liver of Wistar rats

This study was planned to investigate the protective effect of l (+)‐ascorbic acid (Vit C) on CCl₄‐induced hepatotoxicity and oxidative stress in the liver of Wistar rats (Rattus Norvegicus, strain Wistar). Twenty‐four adult male Wistar rats were fed with standard rat chow diet for 10 days and randomly were divided into four groups of six each as follows: (1) control, (2) CCl₄, (3) “CCl₄ + Vit C”, (4) Vit C groups. CCl₄ was applied to rats belonging to CCl₄ and “CCl₄ + Vit C” groups subcutaneously at 1 mg kg^?1 dose CCl₄ for 3 days. Vit C applied to “CCl₄ + Vit C” and “Vit C” group rats intraperitoneally at 300 mg kg^?1 dose for 3 days. All rats were sacrificed and livers were quickly removed on the fourth day of the experiment. MDA, total glutathione (T.GSH) levels and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH‐PX) activities were measured in the liver of all groups of rats and also serum alanine amino transferase (ALT) and aspartate amino transferase (AST) activities were detected to determine liver functions in all groups of rats. Histopathological changes were evaluated by light and transmission electron microscopes. In “CCl₄ + Vit C” group, MDA level was significantly decreased (p < 0.05) and SOD, CAT, GSH‐PX activities were significantly increased (p < 0.005, 0.01, 0.05) respectively, T.GSH level was significantly increased (p < 0.005) and serum ALT and AST activities were significantly decreased (p < 0.01, 0.05), respectively, when compared with CCl₄ group. These results show that Vit C has a highly protective effect on hepatotoxicity and oxidative stress caused by CCl₄. Copyright © 2009 John Wiley & Sons, Ltd.     

Exocyst requirement for endocytic traffic directed toward the apical and basolateral poles of polarized MDCK cells

The octameric exocyst complex is associated with the junctional complex and recycling endosomes and is proposed to selectively tether cargo vesicles directed toward the basolateral surface of polarized Madin-Darby canine kidney (MDCK) cells. We observed that the exocyst subunits Sec6, Sec8, and Exo70 were localized to early endosomes, transferrin-positive common recycling endosomes, and Rab11a-positive apical recycling endosomes of polarized MDCK cells. Consistent with its localization to multiple populations of endosomes, addition of function-blocking Sec8 antibodies to streptolysin-O-permeabilized cells revealed exocyst requirements for several endocytic pathways including basolateral recycling, apical recycling, and basolateral-to-apical transcytosis. The latter was selectively dependent on interactions between the small GTPase Rab11a and Sec15A and was inhibited by expression of the C-terminus of Sec15A or down-regulation of Sec15A expression using shRNA. These results indicate that the exocyst complex may be a multipurpose regulator of endocytic traffic directed toward both poles of polarized epithelial cells and that transcytotic traffic is likely to require Rab11a-dependent recruitment and modulation of exocyst function, likely through interactions with Sec15A.     

Familial aggregation of nasal conditioning capacity.

In our previous studies on nasal conditioning, we observed a large variability among individuals to condition inspired air. Although we previously investigated various physiological parameters (age, sex, nasal mucosal temperature, heart rate, blood pressure, and nasal volume) that might underlie these differences, we have been unable to explain this variability. Many proteins and molecules, which are under genetic control and could affect nasal conditioning, are involved in water transport,. In this study, we hypothesized that familial factors may contribute to the differences in nasal conditioning capacity (NCC). We performed a prospective study of 47 sibling pairs. Cold dry air was delivered to the nose, and the total water gradient (TWG) was calculated to determine the NCC. We found a highly significant intraclass correlation of 0.53 (P < 0.0001) between sibling pairs for the TWG. These results suggest that there is a familial basis for nasal conditioning and a large enough genetic component to search for genes explaining the observed correlation.     

Analysis of spatial and temporal variation in the levels of microbial fecal indicators in the major rivers flowing into the Aegean Sea,Turkey

River watersheds in the western part of Turkey (Aegean Sea) are anthropogenically impacted areas, due to the high population density, intensive agricultural and/or industrial activities. The aim of the present survey was to assess the microbiological quality of river waters using indicators of fecal contamination. Five rivers (Meric, Bakircay, Gediz, Kucuk Menderes and Buyuk Menderes) were sampled as seasonally from 2006 to 2008 for fecal coliforms, and fecal streptococci. In order to determine the number of fecal indicator bacteria, membrane filtration method was used. The minimum fecal coliforms and fecal streptococci were counted from the samples taken from the Buyuk Menderes River (5 × 10¹–3 × 10¹ CFU/100 ml) especially in the spring and autumn. The highest fecal coliform result was obtained in winters (1.3 × 10⁶ CFU/100 ml) while maximum fecal streptococci value was detected in autumns (6.3 × 10⁴ CFU/100 ml) in the Kucuk Menderes River during 2006–2008. Additionally, the relationships between the fecal indicator bacteria and physico-chemical parameters (temperature, conductivity and pH) were also evaluated, but no significant relationships were observed between the fecal indicator bacteria and environmental parameters. Considering the findings of these studies, it can be said that there is fecal pollution in the rivers reaching the Aegean Sea. The results show that there are a great number of microbial pollution sources in the areas where the river passes through and thus, in order to implement strategies to improve water quality in these rivers, monitoring of these rivers should continue.     

Adult cardiac-resident MSC-like stem cells with a proepicardial origin

Colony-forming units - fibroblast (CFU-Fs), analogous to those giving rise to bone marrow (BM) mesenchymal stem cells (MSCs), are present in many organs, although the relationship between BM and organ-specific CFU-Fs in homeostasis and tissue repair is unknown. Here we describe a population of adult cardiac-resident CFU-Fs (cCFU-Fs) that occupy a perivascular, adventitial niche and show broad trans-germ layer potency in vitro and in vivo. CRE lineage tracing and embryo analysis demonstrated a proepicardial origin for cCFU-Fs. Furthermore, in BM transplantation chimeras, we found no interchange between BM and cCFU-Fs after aging, myocardial infarction, or BM stem cell mobilization. BM and cardiac and aortic CFU-Fs had distinct CRE lineage signatures, indicating that they arise from different progenitor beds during development. These diverse origins for CFU-Fs suggest an underlying basis for differentiation biases seen in different CFU-F populations, and could also influence their capacity for participating in tissue repair.     

Genome Sequence of Campylobacter jejuni strain 327, a strain isolated from a turkey slaughterhouse

Campylobacter is one of the leading causes of food-borne gastroenteritis and has a high prevalence in poultry. Campylobacter jejuni subsp. jejuni 327 is a subspecies of the genus Campylobacter of the family Campylobacteraceae in the phylum Proteobacteria. The microaerophilic, spiral shaped, catalase positive bacterium obtains energy from the metabolism of amino acids and Krebs cycle intermediates. Strain 327 was isolated from a turkey slaughter production line and is considered environmentally sensitive to food processing (cold, heat, drying) and storage conditions. The 327 whole genome shotgun sequence of 1,618,613 bp long consists of 1,740 protein-coding genes, 46 tRNA genes and 3 rRNA operons. A protein based BLAST analysis places the turkey isolate 327 close to the human clinical strain 81116 (NCTC 11828).     

Cutaneous leishmaniasis caused by Leishmania infantum transmitted by Phlebotomus tobbi

Transmission of cutaneous leishmaniasis (CL) caused by Leishmania infantum was studied in South Anatolia, Turkey. Small, non-ulcerating lesions prevailed and patients were negative in rK39 tests for antibody detection for human visceral leishmaniasis (VL). The most abundant sand fly species, Phlebotomus tobbi, was found positive for Leishmania promastigotes with a prevalence of 1.4% (13 out of 898 dissected females). The isolated strains were identical with those obtained from patients with CL and were typed as L. infantum. Phylogenetic analysis revealed similarity to MON-188 and a clear difference from the MON-1 clade. Blood-meal identification showed that P. tobbi feeds preferentially on cattle and humans. This finding, the high number of CL patients and relative scarcity of dogs in the focus, suggests that the transmission cycle could be anthroponotic.