Determination of pharmacokinetics of flurbiprofen in Pakistani population using modified HPLC method

Pharmacokinetics of flurbiprofen has been studied in different populations, especially in Caucasian. However, there are very few studies reported from Eastern part of world. Previous studies suggested that genetic and environmental factors may cause inter-individual differences in flurbiprofen disposition, so we investigated the pharmacokinetics of flurbiprofen in Pakistani subjects. A single oral dose of 100 mg of flurbiprofen was administered to 22 healthy male Pakistani adults after overnight fasting for 10 h. Periodical blood sampling was done at 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 7, 8, 10, 12, and 24 h after dosing. Plasma concentration of flurbiprofen was determined by a modified high-performance liquid chromatography method, which was simple, sensitive, less time consuming and economical with ordinary internal standard. The method was validated according to ICH guidelines and was found to be sensitive, accurate and precise. The pharmacokinetic parameters observed in Pakistani subjects when compared with other populations (USA, UK, Canadian, French, and Indian) did not show considerable ethnic differences. However, one subject's data was suggestive of being poor metabolizer of flurbiprofen which supports the presence of CYP2C9 polymorphism contributing to inter-individual differences in flurbiprofen disposition. Pharmacogenomic studies are needed to verify this hypothesis.     

Quantitative Particle Uptake by Cells as Analyzed by Different Methods

There is a large number of two‐dimensional static in vitro studies about the uptake of colloidal nano‐ and microparticles, which has been published in the last decade. In this Minireview, different methods used for such studies are summarized and critically discussed. Supplementary experimental data allow for a direct comparison of the different techniques. Emphasis is given on how quantitative parameters can be extracted from studies in which different experimental techniques have been used, with the goal of allowing better comparison.     

CRISPR-Cas13a mediated nanosystem for attomolar detection of canine parvovirus type 2

The CPV-2 DNA extracted from dog's intestine was amplified using RPA and transcribed into an RNA copy. The RNA copy was incubated with Cas13a and crRNA, upon activation collateral cleavage activity of Cas13a cleaves all the target RNA and nonspecific RNA in the vicinity producing fluorescent signals within 30 min.     

Reversible chain transfer between organoyttrium cations and aluminum: synthesis of aluminum-terminated polyethylene with extremely narrow molecular-weight distribution

Aminopyridinato-ligand-stabilized organoyttrium cations are accessible in very good yield through alkane elimination from trialkyl yttrium complexes with sterically demanding aminopyridines, followed by abstraction of one of the two alkyl functions using ammonium borates. At 80 degrees C and in the presence of small amounts of aluminum alkyl compounds, very high ethylene polymerization activities are observed if very bulky aminopyridinato ligands are used. During these polymerizations a reversible polyethylene chain transfer is observed between the organoyttrium cations and aluminum alkyls. The chain-transfer catalyst system described here is able to produce relatively long-chain (up to 4000 g mol-1) Al-terminated polyethylene with a molecular-weight distribution<1.1. In the synthesis of higher molecular PE a slight increase in polydispersity with increasing chain length (15,600 g mol-1, approximately 1.4) is observed owing to reduced reversibility caused by higher viscosity and precipitation of polymer chains (temperature of 80-100 degrees C).     

Attempted Reduction of Divalent Rare Earth Iodo Aminopyridinates

Rare examples of amido‐iodo complexes of selected divalent lanthanides can be synthesized by using deprotonated Ap*H {Ap*H = 2,6‐diisopropylphenyl)‐[6‐(2,4,6‐triisopropylphenyl)‐pyridin‐2‐yl]‐amine} as a stabilizing ligand. Reaction of [Ap*K]_n with [LnI₂(thf)_n] (Ln = Eu, Yb, n = 4,5) in THF leads to [Ln(Ap*)I(thf)₂]₂ (Ln = Eu, Yb). An attempted reduction of these divalent heteroleptic complexes with KC₈ to synthesize complexes containing an unsupported Ln–Ln bond resulted in the formation of [Ln(Ap*)₂(thf)₂]. These lanthanide complexes were characterized by X‐ray structure analysis.     

New thermodynamics of entropy generation minimization with nonlinear thermal radiation and nanomaterials

This research addressed entropy generation for MHD stagnation point flow of viscous nanofluid over a stretching surface. Characteristics of heat transport are analyzed through nonlinear radiation and heat generation/absorption. Nanoliquid features for Brownian moment and thermophoresis have been considered. Fluid in the presence of constant applied inclined magnetic field is considered. Flow problem is mathematically modeled and governing expressions are changed into nonlinear ordinary ones by utilizing appropriate transformations. The effects of pertinent variables on velocity, nanoparticle concentration and temperature are discussed graphically. Furthermore Brownian motion and thermophoresis effects on entropy generation and Bejan number have been examined. Total entropy generation is inspected through various flow variables. Consideration is mainly given to the convergence process. Velocity, temperature and mass gradients at the surface of sheet are calculated numerically.     

Energy conditions and conservation laws in LTB metric via Noether symmetries

In this paper, we have investigated Noether symmetries in Lemaitre–Tolman–Bondi (LTB) metric. Using the Lagrangian associated with the LTB metric, the set of determining equations for Noether symmetries is obtained and then integrated in several cases. It is shown that the LTB metric can be classified in to eight distinct classes corresponding to Noether algebra of dimension 4, 5, 6, 7, 8, 9, 11 and 17. The obtained Noether symmetries are compared with Killing and homothetic vectors. The well known Noether’s theorem is used to find the expressions for conservation laws in each case. Moreover, it is shown that most of the obtained metrics are anisotropic or perfect fluid models which satisfy certain energy conditions and the equation of state.