A CONTROLLED RELEASE MICROSPHERE FORMULATION OF AN ANTI-DIABETIC DRUG AND CHARACTERIZATION OF THE MICROSPHERE

Objective: Here the objective of this study was to prepare and characterize sustained release metformin loaded microsphere formulation which was prepared by W1/O/W2 emulsion solvent evaporation technique.Methods: Guar gum and sodium alginate were used as a matrix building material, whereas ethyl cellulose was applied as a coating polymer. Here various formulations were prepared by changing the drug and guar gum ratio, and the subsequent drug entrapment efficiency (DEE) and drug release were compared and evaluated.Results: Scanning Electron Microscopy (SEM) studies revealed spherical particles with a smooth appearance. Fourier-transform infrared spectroscopy (FTIR) showed there was no interaction between the ingredients in the final formulation. X-ray Diffraction (XRD) studies showed the emergence of polymorphic forms in the final formulation. The drug entrapment in the final drug loaded microsphere formulations was varied from 30-66.78%. The drug release studies showed the continuous release of the drug through twelve hours. The optimized formulation (f2) found to release 71.5% of drugs at the end of the 12th hour following zero order release kinetics.Conclusion: The increase in gum concentration in the W1 phase, which enhances viscosity in the W1 phase, resulting in an increase in the drug entrapment up to an optimum level and a decrease in the release rate. So, it can prolong the action. So by using this tool, we can say that metformin loaded microsphere formulation would be a suitable pharmaceutical formulation for the treatment of diabetic patients in modern drug therapy for its prolonged action. Â

Evidence of a compensated semimetal with electronic correlations at the CNP of twisted double bilayer graphene

Recently, magic-angle twisted bilayer graphene (MATBLG) has shown the emergence of various interaction-driven novel quantum phases at the commensurate fillings of the moir'e superlattice, while the charge neutrality point (CNP) remains mostly a vanilla insulator. Here, we show an emerging phase of nearly compensated semimetallicity at the CNP of twisted double bilayer graphene (TDBLG), a close cousin of MATBLG, with signatures of electronic correlation. Using electrical and thermal transport, we find almost two orders of magnitude enhancement of the thermopower in magnetic fields much smaller than the extreme quantum limit, accompanied by a large magnetoresistance($\sim 2500\%$) at CNP. This provides indisputable experimental evidence that TDBLG near CNP is a compensated semimetal. Moreover, at low temperatures, we observe an unusual sublinear temperature dependence of resistance. A recent theory predicts the formation of an excitonic metal near CNP, where small electron and hole pockets coexist. We understand the sublinear temperature dependence in terms of critical fluctuations in this theory

Effect of Headgroup on DNA−Cationic Surfactant Interactions

The interaction behavior of DNA with different types of hydroxylated cationic surfactants has been studied. Attention was directed to how the introduction of hydroxyl substituents at the headgroup of the cationic surfactants affects the compaction of DNA. The DNA−cationic surfactant interaction was investigated at different charge ratios by several methods like UV melting, ethidium bromide exclusion, and gel electrophoresis. Studies show that there is a discrete transition in the DNA chain from extended coils (free chain) to a compact form and that this transition does not depend substantially on the architecture of the headgroup. However, the accessibility of DNA to ethidium bromide is preserved to a significantly larger extent for the more hydrophilic surfactants. This was discussed in terms of surfactant packing. Observations are interpreted to reflect that the surfactants with more substituents have a larger headgroup and therefore form smaller micellar aggregates; these higher curvature aggregates lead to a less efficient, “patch-like” coverage of DNA. The more hydrophilic surfactants also presented a significantly lower cytotoxicity, which is important for biotechnological applications

Is there any difference in efficacy of oral sildenafil therapy in primary vs secondary Pulmonary Arterial Hypertension?

Objective: Oral sildenafil, a phosphodiesterase 5 inhibitor,is now accepted mode of therapy for symptomatic Pulmonary arterial hypertension(PAH).As the pathobiologic mechanisms are different in primary and secondary PAH, we undertook this study to find out any significant difference in efficacy of oral sildenafil therapy in primary versus secondary PAH. Methods: It was an unicentric parallel group longitudinal study. After selection and baseline investigations,all the patients of primary and secondary PAH were given sildenafil in fixed doses (50 mg thrice daily). Study parameters: 1. Distance covered in 6 minute walk test (6MWT), 2.Pulmonary arterial pressure (PAP) by trans-thoracic Doppler echocardiography, 3.quality of life (QOL) score assessed by Minnesota living with heart disease questionnaire. At the end of 6 weeks, 6 MWT, PAP, QOL were compared to the baseline value. Results: 42 subjects completed the study.20 subjects had primary PAH and 22 had secondary PAH. Sildenafil therapy was effective in both groups in reducing PAP, increase in distance covered in 6 minute walk and reducing QOL score. Reduction of PAP is significantly more in primary PAH than secondary PAH but no such difference was found in 6 MWT and QOL score. Conclusion: Though lowering of pulmonary arterial pressure in primary PAH is significantly lower than secondary PAH, this is not translated in better symptomatic relief. Key words: primary pulmonary hypertension, secondary pulmonary hypertension, sildenafil, pulmonary arterial pressure, 6 minute walk test

Development of Derivatives of 3, 3′-Diindolylmethane as Potent Leishmania donovani Bi-Subunit Topoisomerase IB Poisons

Background: The development of 3, 39-diindolyl methane (DIM) resistant parasite Leishmania donovani (LdDR50) by adaptation with increasing concentrations of the drug generates random mutations in the large and small subunits of heterodimeric DNA topoisomerase I of Leishmania (LdTOP1LS). Mutation of large subunit of LdTOP1LS at F270L is responsible for resistance to DIM up to 50 mM concentration. Methodology/Principal Findings: In search of compounds that inhibit the growth of the DIM resistant parasite and inhibit the catalytic activity of mutated topoisomerase I (F270L), we have prepared three derivatives of DIM namely DPDIM (2,29diphenyl 3,39-diindolyl methane), DMDIM (2,29-dimethyl 3,39-diindolyl methane) and DMODIM (5,59-dimethoxy 3,39diindolyl methane) from parent compound DIM. All the compounds inhibit the growth of DIM resistant parasites, induce DNA fragmentation and stabilize topo1-DNA cleavable complex with the wild type and mutant enzyme. Conclusion: The results suggest that the three derivatives of DIM can act as promising lead molecules for the generation of new anti-leishmanial agents

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio