Comparative evaluation of phenotypic and genotypic methods for the rapid and cost-effective detection of carbapenemases in extensively drug resistant Klebsiella pneumoniae.

PURPOSE: Carbapenemases are the enzymes that can hydrolyze carbapenems and other ß-lactam antibiotics. These enzymes confer resistance to multiple antibiotics and act as a stumbling block in the treatment of infections caused by gram-negative bacteria. Therefore, rapid and specific detection of these enzymes is crucial for deciding the course of treatment and better clinical outcomes. MATERIAL AND METHODS: This study was conducted to compare various phenotypic and PCR based methods for the detection of carbapenemases in carbapenem- and colistin-resistant Klebsiella pneumoniae. One hundred clinical isolates of extensively resistant Klebsiella pneumoniae were included in the study. Phenotypic detection for carbapenemases was performed by Rapidec® Carba NP (Biomerieux), modified carbapenem inactivation method (mCIM), imipenem-ethylenediaminetetraacetic acid disk synergy (EDS), double disk synergy test using mercaptopropionic acid (DDST-MPA), and combined disk method (CD) and for colistin by microbroth dilution method. Genotypic detection for carbapenemases and colistin resistance was performed by targeted PCR. RESULTS: The sensitivity of Carba NP test and mCIM were positive in 95% and 96% respectively and specificity was 100% for both methods. The sensitivity of EDS, DDST-MPA, and CD were 55.6%, 88.9% and 54.5% respectively. Among the carbapenem resistance genes, blaOXA-48 (82%) genes were the most prevalent. Among metallo-beta lactamases, blaVIM (56%) was most common followed by blaNDM (54%) and blaIMP (20%). The mcr-1 gene for colistin resistance was not detected in any isolate. CONCLUSION: Among the five phenotypic assays analyzed, the mCIM is the most simple, inexpensive, accurate and reproducible method for carbapenemase detection in Klebsiella pneumoniae. The DDST-MPA test provides the best sensitivity for the detection of carbapenemases, although specificity is low. These tests, when applied in a clinical laboratory and assessed by the microbiologist, can help in guiding the course of treatment.

In Vitro Assessment of Core-Shell Micellar Nanostructures of Amphiphilic Cationic Polymer-Peptide Conjugates as Efficient Gene and Drug Carriers.

Design and development of biocompatible, biodegradable and stable dual delivery systems for drug and gene is the need of the hour. Here, we have designed a strategy to develop carrier systems consisting of above mentioned properties by (a) incorporating an unnatural amino acid in the peptide backbone, and b) conjugating a low molecular weight cationic polymer (polyethylenimine, PEI) for incorporating cationic charge. Using this strategy, we have synthesized a small series of Boc-FΔF-AH-polyethylenimine conjugates by varying the concentration of Boc-FΔF-aminohexanoic acid, viz., PP-1, PP-2 and PP-3. These conjugates self-assembled in aqueous medium to form micelles in the size range of ~144-205 nm with zeta potential ~ +7.9-14.2 mV bearing core-shell type of conformation. Positive surface of the micelles facilitated the binding of plasmid DNA as well as transportation inside the cells. The hydrophobic core of the nanostructures helped in the encapsulation of the hydrophobic drug molecule, which was then got released in a controlled manner. DNA complexes of the conjugates were not only found non-toxic but also exhibited higher transfection efficacy than the native polymer and Lipofectamine. Altogether, these nanostructures are capable of delivering a drug and a gene simultaneously in vitro and could be used as next-generation delivery agents.

Assessment of Palatal Plane and Occlusal Plane for Determining Anteroposterior Jaw Relation.

INTRODUCTION: Sagittal jaw relationship is an important parameter for orthodontic treatment planning. Angular and linear measurements both have been proposed and used in orthodontic cephalometrics to assess the sagittal jaw relationships. However, angular measurement has been questioned over the years for its reliability as a result of changes in facial height, jaw inclination and the variable positions of Nasion. So, the objective of our study was to assess the linear anteroposterior jaw relation in a sample of Nepali population using occlusal (Wits appraisal) and palatal planes as reference lines. METHODS: A descriptive cross-sectional study was conducted using the lateral cephalogram of 101 individuals visiting the Department of Orthodontics, Kantipur Dental College, Kathmandu, Nepal. Individuals with Class I skeletal relation were selected using convenience sampling method. Radiographs were standardised and traced. Occlusal and palatal planes were drawn that were bisected by the perpendicular lines from Point A and Point B. The linear distances between the intersections were measured to determine sagittal jaw relations. RESULTS: In Nepali individuals with normal ANB angle (3.05°±2.511°), the sagittal jaw relation with reference to occlusal (Wits appraisal) and palatal planes were found to be 0.203±3.343mm and 3.574±4.074mm respectively. CONCLUSIONS: Various methods has been proposed and used to assess the sagittal jaw relation and each method has its own strength and limitations. So, it is well advised to use additional cephalometric analysis whenever possible before arriving at any diagnosis and treatment plans.

Emerging trends in contract research industry in India.

A Contract Research Organization (CRO) is a service organization that provides support to the pharmaceutical industry and offers a wide range of "outsourced" pharmaceutical research services to aid in R&D process and is thus an essential tool for undertaking clinical trials in the present scenario when high stakes are involved in the drug discovery process. This industry also offers a safe option of investment as the industry is largely recession-proof, with a significant upscale growth. Presently India occupies a very small pie of the global market share in the Clinical Trials Industry but it is estimated to conduct nearly 5% of global clinical trials by 2012. The global CRO industry valued $18 bn in 2008 and the market is expected to grow at an annual rate of 14% between 2009 and 13. Top multinational pharmaceuticals companies are venturing into the Indian business, in collaboration with the Indian Drug Companies. According to a recent study by Mckinsey & Company, the Indian Clinical Research Industry can attract $1.5 bn of revenue from US and EU by 2010. Such an increase in outsourcing from the western countries has led the global pharma companies and Indian entrepreneurs to set up Contract Research Organizations (CROs) in India. To bring this into realization and fulfil the market demand, while simultaneously aiding in improving the country's economical standards and market position, joint and well-coordinated efforts on part of the government, industry, and working professionals are needed in terms of regulatory affairs, audits, transparency in work affairs, garnering patient confidence, and pharmacovigilance.