Prevalence of Hepatitis A virus (HAV) and Hepatitis E virus (HEV) in the patients presenting with acute viral hepatitis.

BACKGROUND: Hepatitis A virus (HAV) and Hepatitis E virus (HEV) are both enterically transmitted, resulting in acute viral hepatitis (AVH) in developing countries. They pose major health problems in our country. This study was done to determine prevalence of HAV and HEV in patients presenting with AVH and the co-infection of HAV and HEV in these patients. MATERIALS AND METHODS: A cross-sectional study of 2-years duration was conducted in the Department of Microbiology, KMC, Mangalore. A non-random sampling of 958 patients presenting with AVH was considered in the study. On the basis of history, serum samples were analysed for IgM anti-HAV and IgM anti-HEV for the detection of HAV and HEV, respectively using commercially available ELISA kits. Data collected was analysed by using Statistical Package for the Social Sciences (SPSS) version 11.5. RESULTS: The seroprevalence of HAV- and HEV-positive patients were 19.31% and 10.54%, respectively. The seroprevalence of both HAV and HEV in patients with acute viral hepatitis was 11.5%. The prevalence of HAV and HEV among males (68% and 31%) was higher than in females (31% and 20%) and was predominantly seen among young adults. These infections were predominantly seen during end of monsoons and beginning of winter. CONCLUSION: Though the prevalence of HAV is much higher than that of HEV, co-infection rate of 11.5% mandates the screening for HEV which will be of immense importance in pregnant women and improving levels of personal hygiene among higher socio-economic population. These data will be essential for planning of future vaccination strategies and for better sanitation programme in this part of the country.

Clinicomicrobiological analysis of patients with cholangitis.

Acute cholangitis is inflammation of biliary ductal system from infection with an associated biliary obstruction. This retrospective study was done to determine the factors responsible for cholangitis and the microbiological profile of the bile in patients with cholangitis. In the study involving 348 patients, 36.4% had associated malignancy. A total of 54% of the bile samples were positive for aerobic culture. Nearly 66-73% of the Escherichia coli and Klebsiella isolates were Extended spectrum beta lactamases (ESBL) producers. Two isolates of Candida spps were also obtained. Polymicrobial infection was seen in 31.5% of the culture positive cases. Ideal antibiotics in case of cholangitis would be those which are excreted in the bile such as third-generation cephalosporins, ureidopenicillins, carbapenems and fluoroquinolones to combat resistance and polymicrobial aetiology. Anti-fungal drugs may also be necessary if the patient is not responding to biliary decompression and antibacterial agents to prevent fungaemia.

A role for VICKZ proteins in the progression of colorectal carcinomas: regulating lamellipodia formation.

VICKZ proteins are a highly conserved family of RNA binding proteins, implicated in RNA regulatory processes such as intracellular RNA localization, RNA stability, and translational control. During embryogenesis, VICKZ proteins are required for neural crest migration and in adults, the proteins are overexpressed primarily in different cancers. We hypothesized that VICKZ proteins may play a role in cancer cell migration. In patients, VICKZ expression varies with tumour type, with over 60% of colon, lung, and ovarian tumours showing strong expression. In colorectal carcinomas (CRCs), expression is detected at early stages, and the frequency and intensity of staining increase with progression of the disease to lymph node metastases, of which 97% express the protein at high levels. Indeed, in stage II CRC, the level of VICKZ expression in the primary lesion correlates with the degree of lymph node metastasis. In culture, VICKZ proteins rapidly accumulate in processes at the leading edge of PMA-stimulated SW480 CRC cells, where they co-localize with beta-actin mRNA. Two distinct cocktails of shRNAs, each targeting all three VICKZ paralogues, cause a dramatic drop in lamellipodia and ruffle formation in stimulated cells. Thus, VICKZ proteins help to facilitate the dynamic cell surface morphology required for cell motility. We propose that these proteins play an important role in CRC metastasis by shuttling requisite RNAs to the lamellipodia of migrating cells.

Neurotrophin-induced transport of a beta-actin mRNP complex increases beta-actin levels and stimulates growth cone motility.

Neurotrophin regulation of actin-dependent changes in growth cone motility may depend on the signaling of beta-actin mRNA transport. Formation of an RNP complex between the beta-actin mRNA zipcode sequence and Zipcode Binding Protein 1 (ZBP1) was required for its localization to growth cones. Antisense oligonucleotides to the zipcode inhibited formation of this RNP complex in vitro and the neurotrophin-induced localization of beta-actin mRNA and ZBP1 granules. Live cell imaging of neurons transfected with EGFP-ZBP1 revealed fast, bidirectional movements of granules in neurites that were inhibited by antisense treatment, as visualized by FRAP analysis. NT-3 stimulation of beta-actin protein localization was dependent on the 3'UTR and inhibited by antisense treatment. Growth cones exhibited impaired motility in the presense of antisense. These results suggest a novel mechanism to influence growth cone dynamics involving the regulated transport of mRNA.

A parafusin-related Toxoplasma protein in Ca2+-regulated secretory organelles.

We cloned a gene, PRPI, of Toxoplasma gondii encoding a 637-amino-acids protein having a calculated mass of 70 kDa. The sequence showed high homology to parafusin, a protein that in Paramecium tetraurelia participates in Ca2+-regulated exocytosis and is a paralog of phosphoglucomutase. We show that Toxoplasma gondii homogenate and an expressed recombinant PRP1 fusion protein cross-react with a specific peptide-derived antibody to parafusin in Western blots. Antibodies to the recombinant PRP1 showed cross-reaction with parafusin and recognized PRP1, as bands at M, 63 x 10(3) and 68 x 10(3), respectively. PRP1 is labeled when Toxoplasma gondii cells are incubated with inorganic 32P and appears as the major band on autoradiograms of SDS-PAGE gels. The localization of PRP1 was examined in secretory organelles of Toxoplasma gondii by deconvolution light microscopy followed by three dimensional reconstruction using pairwise combinations of specific antibodies. PRP1 localized to the apical third of the cell. It co-localized with micronemes, the only secretory organelle the secretion of which is Ca2+ dependent. Quantification of the co-localized stain suggests that only mature micronemes ready for exocytosis have PRP1. These findings suggest that PRP1, parafusin and other members of the phosphoglucomutase superfamily have a conserved role in Ca2+-regulated exocytic processes.

Localization of ASH1 mRNA particles in living yeast.

ASH1 mRNA localizes to the bud tip in Saccharomyces cerevisiae to establish asymmetry of HO expression, important for mating type switching. To visualize real time localization of the mRNA in living yeast cells, green fluorescent protein (GFP) was fused to the RNA-binding protein MS2 to follow a reporter mRNA containing MS2-binding sites. Formation and localization of a GFP particle in the bud required ASH1 3'UTR (untranslated region) sequences. The SHE mutants disrupt RNA and particle localization and SHE 2 and 3 mutants inhibit particle formation as well. Both She3myc and She1myc colocalized with the particle. Video microscopy demonstrated that She1p/Myo4p moved particles to the bud tip at 200-440 nm/sec. Therefore, the ASH1 3'UTR-dependent particle serves as a marker for RNA transport and localization.