Liquid Spreading Induced by In Situ Generation of Metallic Nanoparticles.

Spreading or pinning of a liquid drop on a solid substrate is determined by the surface energy of solid and liquid, topography of substrate surface, and different external forces like electric field, magnetic field, and vibration. Here we present a novel mechanism of depinning, driven by in situ generation of a species following reaction between a constituent of the droplet and one in the substrate. In particular, fluoro-carbon (FC) functionalized agarose and pHEMA gels are used as the substrates; the substrate is soaked with chloroauric acid. A drop of poly(dimethylsiloxane) (PDMS) mixed with the cross-linking agent is dispensed on it. The drop does not spread in absence of the salt, but as the salt concentration increases, the spreading diameter increases with decrease in the contact angle. The Si-H group, present as a constituent in the cross-linking agent, reduces the salt, leading to in situ generation of gold nanoparticles, that mitigates the pinning effect of the drop and the drop spreads.

Diagnostic role of magnetic resonance cholangiopancreatography in evaluation of obstructive biliopathies and correlating it with final diagnosis and clinical profile of patients.

AIMS AND OBJECTIVE: We assessed the utility of magnetic resonance cholangiopancreatography (MRCP) as a noninvasive diagnostic tool in patients with obstructive biliopathies. MATERIALS AND METHODS: A prospective study was conducted on 54 patients with clinically suspected biliary obstruction. MRCP in these patients was compared and correlated with final diagnosis and their clinical profile. STATISTICAL ANALYSIS: Sample profile was described in terms of sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy. Pearson's Chi-square statistics was used to assess the strength of association between diagnostic accuracy of MRCP and final diagnosis. RESULTS: Out of the 54 patients, 50 had biliary obstruction. The cause of biliary obstruction was finally identified on the basis of direct cholangiography/surgery/histopathology. In 52 of the 54 patients, MRCP agreed with final diagnosis in identifying the level of block. MRCP agreed with final diagnosis in identifying the cause of obstruction in 48 of the 54 patients (89%). Sensitivity of MRCP in identifying the level of obstruction in comparison with final diagnosis was 100%, while diagnostic accuracy of MRCP in identifying the level of obstruction in comparison with final diagnosis was 96.29%. The correlation between MRCP and final diagnosis in diagnosing cause of obstruction was 0.95 (Pearson's correlation coefficient, P = 0.017). CONCLUSION: MRCP is a safe ionizing radiation and iodinated contrast free modality which has the ability to display the biliary tree by combining the advantages of projectional and cross-sectional imaging.

Lymphadenovarix of the head-neck region--a rare presentation of Bancroftian filariasis.

Cystic swellings of the neck in children have limited differential diagnoses, often either lymphatic or vascular malformations. Other cystic inflammations can be the result of tuberculous abscesses, suppurated lymph nodes and actinomycosis. Microfilaria causing lmphadenovarix of head-neck region has not yet been described in the literature. A 10-year-old Indian boy presented with an asymptomatic cystic neck mass of 8 months duration. Aspiration of the swelling demonstrated numerous Wuchereria bancrofti microfilaria and the patient responded well to 6 weeks of daily anti-filarial treatment using diethylcarbamazine citrate (6mg kg(-1) day(-1)). This appears to be the first report of microfilariae-associated lymphadenovarix of head-neck region. Though rare, filariasis should be considered as a differential diagnosis for aberrant swellings where lymphatic filarids are endemic.

Discovery of conformationally rigid 3-azabicyclo[3.1.0]hexane-derived dipeptidyl peptidase-IV inhibitors.

The induction of conformationally restricted N-(aryl or heteroaryl)-3-azabicyclo[3.1.0]hexane derivatives at P(2) region of compounds of 2-cyanopyrrolidine class was explored to develop novel DPP-IV inhibitors. The synthesis, structure-activity relationship, and selectivity against related proteases are delineated.