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Maintaining the safety and quality of manufactured food is an important concern for producers, government and consumers in Bangladesh. The nutritional value of food gradually reduces over time, until it finally becomes unsafe to consume and may cause harm to health. Then again, consumers throw out a large amount of manufactured food after the expiry date, believing it is not safe to consume. Thus, proper labelling of manufacturing and expiry dates of food on packet can protect both the safety and quality of food and save a large amount of food from being wasted. The legislators of Bangladesh do not prescribe any rules or regulations for food producers, which obliges manufacturers to use scientific methods for identifying expiry dates. Moreover, food producers, importers and suppliers use unspecific and confusing terms to indicate the manufacturing and expiry dates of food. This study finds that the date labelling of manufactured food issue in Bangladesh is inadequately regulated, triggering confusion among consumers, manufacturers, sales staff and regulatory authorities. Regulatory loopholes in date labelling contribute to food waste and threaten public health. These issues warrant the enacting of a comprehensive law establishing an effective regulatory body to oversee date labelling of manufactured and processed food. [ABSTRACT FROM AUTHOR]

There is a growing body of evidence supporting an intimate association of immune activation with the pathogenesis of cardiovascular diseases, including atherosclerosis. Uptake of oxidized low-density lipoprotein (oxLDL) through scavenging receptors promotes the formation of mature lipid-laden macrophages, which subsequently leads to exacerbation of regional inflammation and atherosclerotic plaque formation. In this study, we first examined changes in the mRNA level of the lectin-like oxLDL receptor-1 (LOX-1) in the mouse macrophage cell line RAW264.7 and the human PMA-induced macrophage cell line THP-1 after LPS stimulation. LPS significantly up-regulated LOX- 1 mRNA in RAW264.7 cells; LOX-1 cell-surface protein expression was also increased. Flow cytometry and fluorescence microscopy analyses showed that cellular uptake of fluorescence (Dil)-labeled oxLDL was significantly augmented with LPS stimulation. The augmented uptake of Dil-oxLDL was almost completely abrogated by treatment with an anti-LOX-1 antibody. Of note, knockdown of Erk1/2 resulted in a significant reduction of LPS-induced LOX-1 up-regulation. Treatment with U0126, a specific inhibitor of MEK, significantly suppressed LPS-induced expression of LOX-1 at both the mRNA and protein levels. Furthermore, LOX- 1 promoter activity was significantly augmented by LPS stimulation; this augmentation was prevented by U0126 treatment. Similar results were also observed in human PMA-induced THP-1 macrophages. Taken together, our results indicate that LPS up-regulates LOX-1, at least in part through activation of the Erk1/2 signaling pathway, followed by augmented cellular oxLDL uptake, thus highlighting a critical role of TLR4-mediated aberrant LOX-1 signaling in the pathogenesis of atherosclerosis. [ABSTRACT FROM AUTHOR]

The seventh cholera pandemic caused by Vibrio cholerae O1 El Tor (ET) has been superseded in Asia and Africa by altered ET possessing the cholera toxin (CTX) gene of classical (CL) biotype. The CL biotype of V. cholerae was isolated, along with prototypic and altered ET, during the 1991 cholera epidemic in Mexico and subsequently remained endemic until 1997. Microbiological, molecular, and phylogenetic analyses of clinical and environmental V. cholerae isolated in Mexico between 1998 and 2008 revealed important genetic events favoring predominance of ET over CL and altered ET. V. cholerae altered ET was predominant after 1991 but not after 2000. 7. cholerae strains isolated between 2001 and 2003 and a majority isolated in 2004 lacked CTX prophage (Φ) genes encoding CTX subunits A and B and repeat sequence transcriptional regulators of ET and CL biotypes: i.e., CTXΦ-. Most CTXΦ-V. cholerae isolated in Mexico between 2001 and 2003 also lacked toxin coregulated pili tcpA whereas some carried either tcpAET or a variant tcpA with noticeable sequence dissimilarity from tcpACL. The tcpA variants were not detected in 2005 after CTXΦ+ ET became dominant. All clinical and environmental V. cholerae 01 strains isolated during 2005-2008 in Mexico were CTXΦ+ ET, carrying an additional truncated CTXΦ instead of RS1 satellite phage. Despite V. cholerae CTXΦ- ET exhibiting heterogeneity in pulsed-field gel electrophoresis patterns, CTXΦ+ ET isolated during 2004-2008 displayed homogeneity and clonal relationship with V. cholerae ET N16961 and V. cholerae ET isolated in Peru. [ABSTRACT FROM AUTHOR]

Nucleic acid amplification is a valuable molecular tool not only in basic research but also in application oriented fields, such as clinical medicine development, infectious diseases diagnosis, gene cloning and industrial quality control. A comperehensive review of the literature on the principles, applications, challenges and prospects of different alternative methods of polymerase chain reaction (PCR) was performed. PCR was the first nucleic acid amplification method. With the advancement of research, a no of alternative nucleic acid amplification methods has been developed such as loop mediated isothermal amplification, nucleic acid sequence based amplification, strand displacement amplification, multiple displacement amplification. Most of the alternative methods are isothermal obviating the need for thermal cyclers. Though principles of most of the alternate methods are relatively complex than that of PCR, they offer better applicability and sensitivity in cases where PCR has limitations. Most of the alternate methods still have to prove themselves through extensive validation studies and are not available in commercial form; they pose the potentiality to be used as replacements of PCR. Continuous research is going on in different parts of the world to make these methods viable technically and economically. [ABSTRACT FROM AUTHOR]

Identification and classification of the microorganisms are of utmost importance in the field of environmental, industrial, medical and agricultural microbiology, and microbial ecology. Traditional phenotype-based methods encounter many challenges and shortcomings which limit their usability. Molecular methods offer better solutions in identifying and characterizing microorganisms. Several DNA fingerprinting methods have been developed and are in use already. In principle, most of these methods are based on PCR and restriction site analysis. Some of these methods are still not economic in use and require huge set-up cost. Continuous research is going on around the world to improve the methodology and applicability of these methods as well as to make them economic in use. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the coexistence of Vibrio cholerae O1 El Tor and O139 Bengal strains in Bangladesh. Epidemiologic ecologic surveillance was conducted by the International Centre for Diarrheal Disease Research, Bangladesh (ICDDR,B) from June 2010 to December 2012 in Dhaka, Chhatak and Mathbaria. It is noted that the global pattern of cholera is rapidly changing.

Hydrogen, being the most abundant element, is the driver of many if not most reactions occurring on interstellar dust grains. In hydrogen atom addition reactions, the rate is usually determined by the surface kinetics of the hydrogen atom instead of the other reaction partner. Three mechanisms exist to explain hydrogen addition reactions on surfaces: Langmuir–Hinshelwood, Eley–Rideal, and hot-atom. In gas-grain models, the mechanism that is assumed greatly affects the simulation results. In this work, we quantify the temperature dependence of the rates of atomic hydrogen addition reactions by studying the reaction of H+O3 O2+OH on the surface of a film of non-porous amorphous solid water (np-ASW) in the temperature range from 10 to 50 K. The reaction rate is found to be temperature independent. This disagrees with the results of simulations with a network of rate equations that assume Langmuir–Hinshelwood mechanism through either thermal diffusion or tunneling diffusion; the reaction rates assuming such a mechanism possesses a strong temperature dependence, either explicitly or implicitly, that is not seen experimentally. We suggest that the Eley–Rideal and/or hot-atom mechanism play a key role in hydrogen atom addition reactions, and should be included in gas-grain models. We also suggest that our newly developed time-resolved reactive scattering can be utilized to measure the chemical desorption efficiency in grain surface reactions. [ABSTRACT FROM AUTHOR]

Observations by ISO and Spitzer toward young stellar objects showed that CO2 segregates in the icy mantles covering dust grains. Thermal processing of the ice mixture was proposed as being responsible for the segregation. Although several laboratories studied thermally induced segregation, a satisfying quantification is still missing. We propose that the diffusion of CO2 along pores inside water ice is the key to quantify segregation. We combined Temperature Programmed Desorption and Reflection Absorption InfraRed Spectroscopy to study how CO2 molecules interact on a non-porous amorphous solid water (np-ASW) surface. We found that CO2 diffuses significantly on an np-ASW surface above 65 K and clusters are formed at well below one monolayer. A simple rate equation simulation finds that the diffusion energy barrier of CO2 on np-ASW is 2150 ± 50 K, assuming a diffusion pre-exponential factor of 1012 s−1. This energy should also apply to the diffusion of CO2 on the wall of pores. The binding energy of CO2 from CO2 clusters and CO2 from H2O ice has been found to be 2415 ± 20 K and 2250 ± 20 K, respectively, assuming the same prefactor for desorption. CO2–CO2 interaction is stronger than CO2–H2O interaction, in agreement with the experimental finding that CO2 does not wet the np-ASW surface. For comparison, we carried out similar experiments with CO on np-ASW, and found that the CO–CO interaction is always weaker than CO–H2O. As a result, CO wets the np-ASW surface. This study should be of help to uncover the thermal history of CO2 on the icy mantles of dust grains. [ABSTRACT FROM AUTHOR]

E. coli is the most frequently used host for production of enzymes and other proteins by recombinant DNA technology. E. coli is preferable for its relative simplicity, inexpensive and fast high-density cultivation, well-known genetics, and large number of compatible molecular tools available. Despite all these advantages, expression and production of recombinant enzymes are not always successful and often result in insoluble and nonfunctional proteins. There are many factors that affect the success of cloning, expression, and mass production of enzymes by recombinant E. coli. In this paper, these critical factors and approaches to overcome these obstacles are summarized focusing controlled expression of target protein/enzyme in an unmodified form at industrial level.