Emerging Developments on Pathogenicity, Molecular Virulence, Epidemiology and Clinical Symptoms of Current Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

Middle East respiratory syndrome coronavirus (MERS-CoV) is a recently reported virus that is associated with severe, life threatening and rapidly spreading primarily respiratory illness called the Middle East respiratory syndrome. MERS-CoV possesses a unique positive-sense single-stranded RNA and can undergo rapid mutation in the viral genome. This results in antigenic switching and genetic variation, finally leading to the emergence of novel and new MERS-CoV subtypes which are uncontrollable by vaccines. Researchers are also finding difficulties to sort out therapeutic intervention strategies for MERS-CoV. This virus can spread from human to human, but transmission from dromedary camels to humans plays a crucial epidemiological significance. Dromedary camel acts as “gene mixing vessels” for MERS-CoV and these virus particles undergo rapid change in them. Viral receptors called dipeptidyl peptidase-4 are important receptors for attachment and spread of MERS-CoV in humans. The current method of laboratory confirmation is through real-time polymerase chain reaction on bronchoalveolar lavage, sputum and tracheal aspirates. Unfortunately, till today there are no definite anti-viral drugs available for MERS-CoV

Molecular identification of diarrheal Aeromonas using immuno magnetic polymerase chain reaction (IM-PCR) technique: a comparative study with conventional culture method

Background: Aeromonas are ubiquitous bacteria causing many clinical conditions including acute diarrhea. Diarrheagenic Aeromonas harbors aerolysin gene secreting virulent enterotoxin, aerolysin.Objectives: To develop a molecular and immunological based method for detection of Aeromonas.Methods: Diarrheal Aeromonas strains were identified from stool samples using culture, enterotoxicity testing using mice model. During immune magnetic polymerase chain reaction IM-PCR protocol, aerolysin specific antibodies were bound with immuno magnetic binding. Sensitivity and specificity tests for IM-PCR were conducted.Results: There was high detection of Aeromonas using IM-PCR (12.4 %) technique when compared to low isolation with culture (5.1%). Our study confirmed that some strains of enterotoxic Aeromonas strains were uncultivable. Enterotoxicity tests on culture isolates revealed many strains were negative. IM-PCR detected high, (62/500) rate of identification of Aeromonas with aerolysin toxin gene. Aeromonas species identified after IM-PCR were A. hydrophila (40.3% ), A. veronii (17.7 %), A. caviae (14.5%), A. trota (11.2 %), A. jandei (9.6 %) and A. schuberti (6.4%). All A. trota strains were undetected by cultivation.Conclusion: High sensitivity and specificity of IM-PCR are due to preparation of aerolysin antibodies and immuno magnetic binding, prior to PCR. Since diseases due to Aeromonas are increasingly reported, IM-PCR is recommended for detection from clinical specimens.Keywords: Aeromonas, IM-PCR, acute diarrhea, aerolysin, enterotoxicity

Generation of Oxygen Free Radicals by Proflavine: Implication in Protein Degradation

Proflavine, an acridine dye, is a known DNA intercalating agent. In the present study, we show that proflavine alone on photoillumination can generate reactive oxygen species (ROS). These proflavine-derived ROS cause damage to proteins, and this effect is enhanced when the divalent metal ion Cu (II) is included in the reaction. Bathocuproine, a specific Cu (I) sequestering agent, when present in the reaction mixture containing Cu (II), was found to inhibit the protein degradation, showing that Cu (I) is an essential intermediate in the reaction. The effect of several scavengers of ROS such as superoxide dismutase, sodium azide, potassium iodide, and thiourea were examined on the protein damaging reaction. Potassium iodide was found to be the most effective in inhibiting protein damage followed by sodium azide and thiourea. Our results indicate the involvement of superoxide, singlet oxygen, triplet oxygen, and hydroxyl radicals in proflavine-induced damage to proteins

Monitoring of Noctiluca Bloom in Mandapam and Keelakarai Coastal Waters; Southeast Coast of India

Monitoring the Harmful Algal Blooms was carried out during July to December 2008 in Mandapam and Keelakarai coastal waters of Tamil Nadu, Southeast coast of India. In the month of October several fishes and shellfishes were died due to Noctiluca blooms along these two areas. The present investigation the following species of phyto and zooplankton were found to be common; phytoplankton such as Coscinodiscus sp., Skeletonema costatum, Bacillaria paradoxa, Thallassiothrix frauenfeldii, T. longisima, Leptocylindrus sp., and  zooplankton such as Paracalanus parvus, Acrocalanus gracilis, Pseudodiaptomus serricautatus, Rhincalanus cornutus, R. nasutus, Euterpina acutifrons, Nannocalanus minor, Eucalanus attenuates, E. crassus, Fish larvae, Fish eggs, Barnacle nauplii, Bivalve larvae, Gastropod larvae, Copepod nauplii  and Mysis larvae. The hydrobiological parameters also analysed during bloom and after blooms; the dissolved oxygen (2.6 – 4.9µM L-1) nutrients varied between nitrate (0.66 – 1.01µM L-1) nitrite (0.11 – 0.21µM L-1) phosphate (0.51 – 0.86µM L-1) and silicate (0.81 – 4.2µM L-1)

N-acetyltransferase gene polymorphisms & plasma isoniazid concentrations in patients with tuberculosis

Background & objectives: Variations in the N-acetyltransferase (NAT2) gene among different populations could affect the metabolism and disposition of isoniazid (INH). This study was performed to genotype NAT2 gene polymorphisms in tuberculosis (TB) patients from Chennai, India, and compare plasma INH concentrations among the different genotypes. Methods: Adult patients with TB treated in the Revised National TB Control Programme (RNTCP) in Chennai, Tamil Nadu, were genotyped for NAT2 gene polymorphism, and two-hour post-dosing INH concentrations were compared between the different genotypes. Plasma INH was determined by high-performance liquid chromatography. Genotyping of the NAT2 gene polymorphism was performed by real-time polymerase chain reaction method. Results: Among the 326 patients genotyped, there were 189 (58%), 114 (35%) and 23 (7%) slow, intermediate and fast acetylators, respectively. The median two-hour INH concentrations in slow, intermediate and fast acetylators were 10.2, 8.1 and 4.1 μg/ml, respectively. The differences in INH concentrations among the three genotypes were significant (P<0.001). Interpretation & conclusions: Genotyping of TB patients from south India for NAT2 gene polymorphism revealed that 58 per cent of the study population comprised slow acetylators. Two-hour INH concentrations differed significantly among the three genotypes

Isolation, identification, characterization and antibiotic sensitivity profile of pathogenic Legionella pneumophila isolates from different water sources

Objective: To investigate the prevalence, isolation, identification, characterization, antibiotic profile and pathogenicity of Legionellae isolated from various set of waters. Methods: A total of 400 water samples were collected from different water sources. Water samples were pretreated using acid treatment followed by concentration and culture on buffered charcoal yeast extract agar. Parameters like ability of Legionella isolates to grow in various pH range, effect of different concentrations of chlorine and effect of different temperature optima were set up. Biochemical tests were performed to separate Legionellae into species. Antibiotic sensitivity tests and test for pathogenicity were also conducted on isolated strains. Results: The rates of isolation of Legionella pneumophila (L. pneumophila) in different water sources were found to be 20% (lakes), 10% (ponds), 8% (water-tanks) and 1% (rivers). Most of the isolates could grow in variable pH 6–8 and it could also survive the normal level of chlorination and even at temperature of 42 °C. Isolated species of Legionellae resulted in identification of 5 different species, L. pneumophila being the dominant one. Strains of L. pneumophila were resistant to many antibiotics. Inoculation of Legionellae into intracerebral route of suckling mice revealed that L. pneumophila was the most virulent. Conclusions: Serious and fatal L. pneumophila infections may be transmitted through water. Legionella can survive under various conditions in various water sources. L. pneumophila is the important pathogen causing human disease. Great challenge prevails to health care professionals because these Legionellae acquired antibiotic resistance to many routinely prescribed antibiotics

Sensorless speed and position control of permanent magnet BLDC motor using particle swarm optimization and ANFIS

This paper describes the operation of a Permanent Magnet Brushless Direct Current (PMBLDC) motor without a position sensor. In this case, the sensorless operation is enhanced by an effective hybrid technique that detects the back electromotive force (Back EMF) of the zero crossing point (ZCP) from the terminal voltages. The Adaptive Neuro Fuzzy Interference System (ANFIS) controller, which is based on Particle Swarm Optimization (PSO) and uses PSO to train its operation, is combined in the proposed hybrid analysis. The PMBLDC motor's ANFIS controller receives the line voltages as input, and it uses this information to estimate the sample signals that are then sent to the ZCP detection circuit. Appropriate commutation control of the inverter is generated by the ZCP detecting circuit. By varying the ANFIS consequent parameters, the PSO algorithm iterates until the error between the sample output and the real training data reaches a low value. The MATLAB/Simulink platform is utilized to implement the suggested sensorless controller action. To verify the controller's performance, a comparison with the other soft computing methods is also carried out

Corrosion behavior of Epoxy/ZnO-NiO nanocomposite coating on steel substrate

Corrosion is a very common natural phenomenon which leads to huge losses especially in the building construction, turbines in the industries and several other fields. In this research we synthesized and developed new coating materials containing ZnO-NiO. The fabricated coating was characterized by using different techniques such as SEM, XRD etc. The efficiency of the coating against corrosion was examined using the Tafel experiments and it was observed that the fabricated coating exhibit excellent anti-corrosion under seawater