Prevalence,characterization, and genetic diversity of Listeria monocytogenes isolated from foods of animal origin in North East India

Listeria monocytogenes is a pathogenic microorganism infects man mostly through food. A total of 1615 samples of foods of animal origin and water were collected from retail meat shops of North-Eastern India and processed. Sixty-three (3.9%) samples were positive for L. monocytogenes. Animal origin foods showing the highest prevalence was chevon (9.8%) followed by beef (8.9%), chicken (8.5%), pork (2.8%) and milk (1.8%). The prevalence rate in water from retail meat shops was 10%. Recovered L. monocytogenes were distributed into 3 serogroups, of which 74.6% fit in to 1/2a, 3a serogroup, 17.5% to 1/2b, 3b and 7.9 % to 4b, 4d, 4e serogroups. Thirty-five isolates out of 63 possessed all the tested four virulence genes. RAPD- and ERIC -PCR based analyses jointly revealed a discriminative genetic profile for the L. monocytogenes. On the whole, the occurrence of L. monocytogenes in foods of animal origin of North Eastern India displays public health hazard.     

Extraction and Characterization of Carbon from Bio Waste

Silicon - This study is an effort to utilize agricultural biomass rice husk for useful applications. The biomass has been milled and then pyrolysed at three different temperatures (800, 900 and...     

Correlation between structural properties and gas sensing characteristics of SnO2 based gas sensors

Undoped polycrystalline tin oxide sintered in the temperature range 500–1000 °C has been comprehensively characterized with respect to its response to CO, methane and H₂. Results obtained at an operating temperature of 300 °C show that increasing the sintering temperature leads to a gradual increase in CO sensitivity which reaches a maximum after sintering at 800 °C.     

Freshwater fish as a dietary source of vitamin A in Cambodia

Vitamin A deficiency is a public health problem among children and women. Common Cambodian fish species were sampled and screened for vitamin A content. Contents of vitamin A-active compounds (all-trans retinol, all-trans dehydroretinol, 13-cis retinol, 13-cis dehydroretinol and β-carotene) were determined by high-performance liquid chromatography in samples of raw, whole fish from 29 fish species and in raw, edible parts from 24 species. Replicate samples were analysed in seven selected species. Two species, Parachela siamensis and Rasbora tornieri had very high vitamin A contents >1500 RAE/100 g raw, whole fish, and six species (Barbodes altus, Barbodes gonionatus, Dermogenys pusilla, Puntioplites proctozysron and Thynnichthys thynnoides) had high contents of 500–1500 RAE/100 g raw, whole fish. Two species, Puntioplites proctozysron and Thynnichthys thynnoides had high vitamin A contents in raw, edible parts, after employing traditional cleaning practices. (RAE: The amount of vitamin A active compounds in food is expressed as retinol activity equivalents (RAE), defined as the bioefficacy relative to all-trans-retinol [ West, C. E., & Eilander, A. (2002). Consequences of revised estimates of carotenoid bioefficacy for the control of vitamin A deficiency in developing countries. Journal of Nutrition, 132, 2920S–2926S]. Dehydroretinoids (vitamin A₂) are not converted to all-trans-retinol but have similar metabolic functions. In this paper, RAE refers to the functional bioefficacy as defined by Brouwer et al. [ Brouwer, I. A., Dusseldorp, M. V., West, C. E., & Steegers-Theunissen, R. P. M. (2001). Bioavailability and bioefficacy of folate and folic acid in man. Nutrition Research Review, 14, 267–293]).     

Fungal biotechnology in food and feed processing

Fungi are of excellent value nutritionally, and of great importance to vegetarians. Edible mushrooms are excellent sources of protein, have low-fat content and are free of cholesterol. They are easily cultivable and are consumed either in fresh or processed form. Yeasts and filamentous fungi secrete a plethora of important enzymes in the growth medium together with other secondary metabolites. Most of these are hydrolytic in nature being employed in different food processing industries as well as in refinement of fodder quality. Edible filamentous fungi producing these enzymes present an added advantage for their use in food and feed. In this article these aspects will be discussed along with the results from edible mushroom Termitomyces clypeatus, producing a wide variety of hydrolytic enzymes and products, from our laboratory. It is likely that the functional understanding of different enzyme classes will provide new applications within the food industry in the future.     

Color vision research and trichromatic theory: A historical review.

"After more than a century of scientific research in color vision the trichromatic theory continues to face theoretical contradictions and unexplained facts. Trichromatic theories everywhere should rigorously examine the theory's basic assumptions, provide much more experimental data on the basic visual functions, and honestly ask themselves the question: should the theory be subject to drastic revision or should it be replaced by some other theory?" (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Color Vision Research and the Trichromatic Theory: A Historical Review": Erratum.

Reports an error in the original article by Shakuntala Balaraman (Psychological Bulletin, 1962, 59[4], 434-448). Line 21 on page 435 should read: Manchester Literary and Philosophical Society. (The following abstract of this article appeared in record 1963-06015-001.) After more than a century of scientific research in color vision the trichromatic theory continues to face theoretical contradictions and unexplained facts. Trichromatic theories everywhere should rigorously examine the theory's basic assumptions, provide much more experimental data on the basic visual functions, and honestly ask themselves the question: should the theory be subject to drastic revision or should it be replaced by some other theory? (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of multiple virulence-associated genes in Listeria monocytogenes isolated from bovine mastitis cases

Clinical samples (n=725) were collected from bovines (n=243) which were positive for mastitis using the California mastitis test (CMT) and somatic cell count (SCC). The clinical samples comprising blood (n=239), milk (n=243), and faecal swabs (n=243) were examined for the presence of pathogenic Listeria spp. Isolation of the pathogen was done using selective enrichment in University of Vermont Medium and plating onto Dominguez-Rodriguez isolation agar. Confirmation of the isolates was based on biochemical tests and Christie, Atkins, Munch-Petersen (CAMP) test followed by pathogenicity testing. Pathogenicity of the isolates was tested by phosphatidylinositol-specific phospholipase C (PI-PLC) assay as well as in vivo tests namely, chick embryo and mice inoculation tests. The isolates were subjected to PCR assay for five virulence-associated genes, plcA, prfA, hlyA, actA and iap. Listeria spp. were isolated from 12 (1.66%) samples. Of these 4 (0.55%) and 1 (0.14%) were confirmed as Listeria monocytogenes and Listeria ivanovii, respectively. L. monocytogenes and L. ivanovii were recovered from milk samples (2) and faecal (3) of mastitic cattle (3) and buffaloes (2). L. monocytogenes recovered from the milk of mastitic cattle and L. ivanovii from the faecal swab of buffalo turned out to be pathogenic. However, the remaining three hemolytic isolates exhibiting positive CAMP test turned out to be negative in PI-PLC assay, chick embryo and mice inoculation. L. monocytogenes and L. ivanovii isolates characterized as pathogenic by PI-PLC assay and in vivo pathogenicity tests were found to possess all the five virulence-associated genes and three genes, plcA, prfA and actA respectively. The remaining three hemolytic but non-pathogenic L. monocytogenes isolates were negative for plcA by PCR. It seems that the plcA gene and its expression (in the PI-PLC assay) have an important role as virulence determinants in pathogenic Listeria spp. In conclusion, the PI-PLC assay and virulence genes targeted PCR (plcA, prfA and hlyA genes for L. monocytogenes and plcA, prfA and actA genes for L. ivanovii) hold a good promise as rapid and reliable in vitro alternatives to in vivo pathogenicity tests.     

A retrospective on the design of the GOPI middleware platform

This paper offers a high-level retrospective overview of the GOPI middleware platform which is the outcome of a three-year project aimed at the development of generic, configurable and extensible middleware. GOPI has a clearly defined modular structure, is widely extensible with plug-ins at all levels of the architecture, and natively supports stream interactions as well as standard operation invocation. It offers a generic framework for quality of service (QoS) specification and management, and supports a high-level, multimedia-oriented programming environment that is backwardly compatible with the OMG's CORBA. At its lower levels it supports QoS-driven resource management and features an optimised IIOP stack. Despite its enhanced functionality, GOPI's IIOP performance equals or exceeds that of state-of-the-art CORBA platforms. Correspondence to:G. Coulson (e-mail: geoff@comp.lancs.ac.uk)