Development of a novel and rapid polymerase spiral reaction (PSR) assay to detect Salmonella in pork and pork products.

The polymerase spiral reaction (PSR), a novel isothermal method for targeted DNA amplification, was effectively applied to detect Salmonella in artificially spiked pork. The specificity of the developed PSR was tested using 16 Salmonella and 15 non-Salmonella strains. The PSR assay was 10-fold more sensitive than conventional end-point PCR, having a sensitivity comparable to real-time PCR. The limit of detection of the developed assay was 4 × 103 per gram of pork without enrichment and 4 CFU per gram after a 6 h enrichment. The detection of 4 CFU per gram of pork was achieved within 8 h. The PSR assay was successful, and accurate in comparison to microbiological methods, in detecting Salmonella in 11 of 76 commercial pork samples. Therefore the positive predictive value, negative predictive value and accuracy rate of the developed assay were 100%. Considering its rapidity, user-friendliness, simplicity, cost-effectiveness and equipment-free nature, this PSR assay is a promising tool for the food industry for the detection of Salmonella and prevention of Salmonella outbreaks and recalls.

Pulsed-field gel electrophoresis fingerprinting of Listeria monocytogenes isolates recovered from foods of animal origin and fishes in North-Eastern India.

L isteria monocytogenes is a pathogen of great concern to the food industry. The present study was aimed to explore the clonal relationships amongst L. monocytogenes strains isolated from foods of animal origin (milk, beef, chevon (goat meat), pork and chicken) and fish. Forty-seven L. monocytogenes strains were characterized by pulsed-field gel electrophoresis (PFGE). The PFGE analysis using ApaI and AscI enzymes revealed 37 pulsotypes, with Simpson's discriminatory index of 0.987. This study demonstrated the presence of a few similar L. monocytogenes pulsotypes in different foods of animal origin in different places and years of isolation and this indicates that some L. monocytogenes subtypes may be ubiquitous which are acclimatizing and persisting in different foods of animal origin. This also emphasizes the importance of cross-contamination in local wet markets. Thus, the understanding of genetic diversity will contribute to the development of rational and workable strategies to control this important zoonotic infection.

Roles of microRNA in prostate cancer cell metabolism.

MicroRNAs are non-coding RNA which functions as regulators of genes expression. MicroRNAs have shown their biological functions in cell proliferation, cell cycle, cell metabolism, apoptosis, invasion and metastasis. Cancer cells have the ability to grow in the absence of growth factors by increased metabolic activity. MicroRNAs regulate cell metabolic processes by targeting the key enzymes or transporters and change the metabolic activities by interfering with oncogenes/tumor suppressors, hypoxia, signalling pathways and cell adhesion. This review mainly explains the roles of microRNAs in prostate cancer cell metabolism, such as glucose uptake, glycolysis and lactate secretion, lipid metabolism and interaction with signalling pathways. The relation of microRNAs with hypoxia and cell adhesion in cell metabolism is also highlighted. Therefore, miRNAs help in regulating the metabolism of survived tumor cells, understanding such miRNA-mediated interaction could lead to new avenues in therapeutic application to treat PCa.

Characterization of Marek's disease virus and phylogenetic analyses of meq gene from an outbreak in poultry in Meghalaya of Northeast India.

The aim of the present study was to characterize the virus from the lesions and histopathology of organs associated with mortality in Kuroiler (dual purpose variety of poultry developed and marketed by Keggfarms Pvt. Ltd, India) birds suspected of Marek's disease. Among 1047 birds from two farms of different location with 5.5 and 34% mortality, two types of lesion were observed in post mortem examination; tumors in vital organs-liver, spleen, kidney, lung and ovaries and generalized small nodular tumour in the abdominal cavity. Molecular characterization based on detection of ICP4 gene showed the presence of Marek's disease virus (MDV) from tissues and cell culture adapted isolates in Madin Darby Canine Kidney cell lines. Histopathological examination revealed multinucleated immature lymphoid cells infiltration in the organs. Phylogenetic analysis of the isolates based on meq gene showed the isolates belongs to cluster I genotype of MDV. This is for the first time the MDV virus is characterized from an outbreak in the poultry flock in farmer's field affecting production in Meghalaya state of North east India.