Noninvasive, label-free, and quantitative monitoring of lipase kinetics using terahertz emission technology.

Enzymes catalyze chemical transformations of great importance in many fields, and analysis of the rate of these transformations is equally important. The latter are typically monitored using surrogate substrates that produce quantifiable optical signals, owing to limitations associated with "label-free" techniques that could be used to monitor the transformation of original substrate molecules. In this study, terahertz (THz) emission technology is used as a noninvasive and label-free technique to monitor the kinetics of lipase-induced hydrolysis of several substrate molecules (including the complex substrate whole cow's milk) and horseradish peroxidase-catalyzed oxidation of o-phenylenediamine in the presence of H O .

Comparative study on the inactivation of MS2 and M13 bacteriophages using energetic femtosecond lasers.

Femtosecond (fs) laser irradiation techniques are emerging tools for inactivating viruses that do not involve ionizing radiation. In this work, the inactivation of two bacteriophages representing protective capsids with different geometric constraints, that is, the near-spherical MS2 (with a diameter of 27 nm) and the filamentous M13 (with a length of 880 nm) is compared using energetic visible and near-infrared fs laser pulses with various energies, pulse durations, and exposure times. Intriguingly, the results show that inactivation using 400 nm lasers is substantially more efficient for MS2 compared to M13.

The phage display of Bacillus subtilis Lipase A significantly enhances catalytic activity due to altered nanoscale distribution in colloidal solution.

Screening libraries of mutant proteins by phage display is now relatively common. However, one unknown factor is how the bacteriophage scaffold itself influences the properties of the displayed protein. This communication evaluates the effect of solution parameters on the catalytic activity of phage displayed Bacillus subtilis Lipase A (BSLA), compared to the free enzyme in solution.

A flexible and low-cost polypropylene pouch for naked-eye detection of herpes simplex viruses.

Effective viral detection is a key goal in the development of point of care (POC) diagnostic devices. Loop-mediated isothermal amplification (LAMP) could potentially be a valuable tool for rapid viral detection and diagnosis in commercial and hospital laboratories and resource limited settings. Here, we present a novel polypropylene pouch (PP) for detection of HSV-1 and HSV-2.

Real-time electrochemical detection of pathogen DNA using electrostatic interaction of a redox probe.

Electrostatic redox probes interaction has been widely rendered for DNA quantification. We have established a proof-of-principle by using the ruthenium hexaamine molecule [Ru(NH(3))(6)](3+). We have applied this method for real-time electrochemical monitoring of a loop mediated isothermal amplification (LAMP) amplicon of target genes of Escherichia coli and Staphylococcus aureus by square wave voltammetry (SWV).

Avian influenza virus A (H5N1), detected through routine surveillance, in child, Bangladesh.

We identified avian influenza virus A (H5N1) infection in a child in Bangladesh in 2008 by routine influenza surveillance. The virus was of the same clade and phylogenetic subgroup as that circulating among poultry during the period. This case illustrates the value of routine surveillance for detection of novel influenza virus.

Prevalence of G2P[4] and G12P[6] rotavirus, Bangladesh.

Approximately 20,000 stool specimens from patients with diarrhea visiting 1 urban and 1 rural hospital in Bangladesh during January 2001-May 2006 were tested for group A rotavirus antigen, and 4,712 (24.0%) were positive. G and P genotyping was performed on a subset of 10% of the positive samples (n = 471).

Characterization of a novel P[25],G11 human group a rotavirus.

A novel rotavirus strain (Dhaka6) isolated from a 21-year-old Bangladeshi male patient was characterized by sequence analysis of its VP7 and VP4 gene segments. Phylogenetic analysis of the VP7 gene of the Dhaka6 strain revealed a common evolutionary lineage with porcine G11 rotavirus strains. This isolate is the first reported G11 rotavirus strain infecting a human host.