A Bispecific Antibody Based Assay Shows Potential for Detecting Tuberculosis in Resource Constrained Laboratory Settings

The re-emergence of tuberculosis (TB) as a global public health threat highlights the necessity of rapid, simple and inexpensive point-of-care detection of the disease. Early diagnosis of TB is vital not only for preventing the spread of the disease but also for timely initiation of treatment. The later in turn will reduce the possible emergence of multi-drug resistant strains of Mycobacterium tuberculosis. Lipoarabinomannan (LAM) is an important non-protein antigen of the bacterial cell wall, which is found to be present in different body fluids of infected patients including blood, urine and sputum. We have developed a bispecific monoclonal antibody with predetermined specificities towards the LAM antigen and a reporter molecule horseradish peroxidase (HRPO). The developed antibody was subsequently used to design a simple low cost immunoswab based assay to detect LAM antigen. The limit of detection for spiked synthetic LAM was found to be 5.0 ng/ml (bovine urine), 0.5 ng/ml (rabbit serum) and 0.005 ng/ml (saline) and that for bacterial LAM from M. tuberculosis H37Rv was found to be 0.5 ng/ml (rabbit serum). The assay was evaluated with 21 stored clinical serum samples (14 were positive and 7 were negative in terms of anti-LAM titer). In addition, all 14 positive samples were culture positive. The assay showed 100% specificity and 64% sensitivity (95% confidence interval). In addition to good specificity, the end point could be read visually within two hours of sample collection. The reported assay might be used as a rapid tool for detecting TB in resource constrained laboratory settings

Transcriptome analysis of Bupleurum chinense focusing on genes involved in the biosynthesis of saikosaponins

<p>Abstract</p> <p>Background</p> <p><it>Bupleurum chinense </it>DC. is a widely used traditional Chinese medicinal plant. Saikosaponins are the major bioactive constituents of <it>B. chinense</it>, but relatively little is known about saikosaponin biosynthesis. The 454 pyrosequencing technology provides a promising opportunity for finding novel genes that participate in plant metabolism. Consequently, this technology may help to identify the candidate genes involved in the saikosaponin biosynthetic pathway.</p> <p>Results</p> <p>One-quarter of the 454 pyrosequencing runs produced a total of 195, 088 high-quality reads, with an average read length of 356 bases (NCBI SRA accession SRA039388). A <it>de novo </it>assembly generated 24, 037 unique sequences (22, 748 contigs and 1, 289 singletons), 12, 649 (52.6%) of which were annotated against three public protein databases using a basic local alignment search tool (E-value ≤1e-10). All unique sequences were compared with NCBI expressed sequence tags (ESTs) (237) and encoding sequences (44) from the <it>Bupleurum </it>genus, and with a Sanger-sequenced EST dataset (3, 111). The 23, 173 (96.4%) unique sequences obtained in the present study represent novel <it>Bupleurum </it>genes. The ESTs of genes related to saikosaponin biosynthesis were found to encode known enzymes that catalyze the formation of the saikosaponin backbone; 246 cytochrome P450 (<it>P450</it>s) and 102 glycosyltransferases (<it>GT</it>s) unique sequences were also found in the 454 dataset. Full length cDNAs of 7 <it>P450</it>s and 7 uridine diphosphate <it>GT</it>s (<it>UGT</it>s) were verified by reverse transcriptase polymerase chain reaction or by cloning using 5' and/or 3' rapid amplification of cDNA ends. Two <it>P450</it>s and three <it>UGT</it>s were identified as the most likely candidates involved in saikosaponin biosynthesis. This finding was based on the coordinate up-regulation of their expression with <it>β-AS </it>in methyl jasmonate-treated adventitious roots and on their similar expression patterns with <it>β-AS </it>in various <it>B. chinense </it>tissues.</p> <p>Conclusions</p> <p>A collection of high-quality ESTs for <it>B. chinense </it>obtained by 454 pyrosequencing is provided here for the first time. These data should aid further research on the functional genomics of <it>B. chinense </it>and other <it>Bupleurum </it>species. The candidate genes for enzymes involved in saikosaponin biosynthesis, especially the <it>P450</it>s and <it>UGT</it>s, that were revealed provide a substantial foundation for follow-up research on the metabolism and regulation of the saikosaponins.</p

Micronutrient fortification of food and its impact on woman and child health: A systematic review

Background: Vitamins and minerals are essential for growth and metabolism. The World Health Organization estimates that more than 2 billion people are deficient in key vitamins and minerals. Groups most vulnerable to these micronutrient deficiencies are pregnant and lactating women and young children, given their increased demands. Food fortification is one of the strategies that has been used safely and effectively to prevent vitamin and mineral deficiencies.Methods: A comprehensive search was done to identify all available evidence for the impact of fortification interventions. Studies were included if food was fortified with a single, dual or multiple micronutrients and impact of fortification was analyzed on the health outcomes and relevant biochemical indicators of women and children. We performed a meta-analysis of outcomes using Review Manager Software version 5.1.Results: Our systematic review identified 201 studies that we reviewed for outcomes of relevance. Fortification for children showed significant impacts on increasing serum micronutrient concentrations. Hematologic markers also improved, including hemoglobin concentrations, which showed a significant rise when food was fortified with vitamin A, iron and multiple micronutrients. Fortification with zinc had no significant adverse impact on hemoglobin levels. Multiple micronutrient fortification showed non-significant impacts on height for age, weight for age and weight for height Z-scores, although they showed positive trends. The results for fortification in women showed that calcium and vitamin D fortification had significant impacts in the post-menopausal age group. Iron fortification led to a significant increase in serum ferritin and hemoglobin levels in women of reproductive age and pregnant women. Folate fortification significantly reduced the incidence of congenital abnormalities like neural tube defects without increasing the incidence of twinning. The number of studies pooled for zinc and multiple micronutrients for women were few, though the evidence suggested benefit. There was a dearth of evidence for the impact of fortification strategies on morbidity and mortality outcomes in women and children.Conclusion: Fortification is potentially an effective strategy but evidence from the developing world is scarce. Programs need to assess the direct impact of fortification on morbidity and mortality

Nonlinear magneto-optical rotation in the presence of a radio-frequency field

We report measurements of nonlinear magneto-optical rotation (NMOR) for the D2 line of 87Rb atoms in an antirelaxation-coated vapor cell in the presence of a radio-frequency (rf) field. The experimental NMOR signals as a function of rf field frequency for various rf field powers are compared to a theoretical model based on the density-matrix formalism. The comparison between experiment and theory enables understanding of the ground-state atomic spin polarization dynamics, illustrated using plots of the probability distribution of the atomic angular momentum

Analytical Method Development and Validation of Stability Indicating RP-HPLC Method for The Simultaneous Estimation of Dolutegravir, Emtricitabine and Tenofovir Disproxil Fumarate

A simple, Accurate, precise method was developed for the simultaneous estimation of the Dolutegravir (DUA), Emtricitabine(ECB) and Tenofovir Disoproxil fumarate (TDF) tablet dosage form. Chromatogram was run through Std Kinetex Biphenyl, 250 x 4.6 mm, 5µm. Mobile phase-A containing pH-3.0 Ammonium acetate Buffer &amp; Mobile phase -B containing Degassed mixture of Acetonitrile &amp; Methanol taken in the ratio of 50:50 was pumped through column at a flow rate of 1 mL/min. Diluent used in this method was 0.1% Orthophosphoric acid buffer &amp; Methanol in the ratio of 50:50%v/v. Temperature was maintained at 40°C. Optimized wavelength selected was 260 nm. Retention time of DUA, ECB and TDF were found to be 14.6min, 3.98min and 12.60min. %RSD of the DUA, ECB and TDF were found to be 0.35, 0.47 &amp; 0.40 respectively. %Recovery was obtained as 98.9%, 99.6% and 99.3% for DUA, ECB and TDF respectively. Both the runtime and retention times were decreased, so this method developed was simple and economical this can be adopted in regular quality control in pharma industries

Impact of Gap Years Following Medical School Graduation on Resident Research Productivity in Ophthalmology

Background Gap years following medical school graduation have become more common, but research into their tangible career benefit is lacking. Examining the impact of gap years on resident scholarly productivity in ophthalmology may provide insight generalizable to all specialties