296 research outputs found

    Conformational Study of Polyelectrolytes

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    We have presented the conformational study of anionic polyelectrolyte, sodium sulfonated polystyrene having molecular weight 70kDa with the variation of the added electrolyte concentration. From the zeta potential measurements we found the decrease in particle mobility on increasing the salt concentration from 0M to 0.15M resulting in a decrease in the effective charge on the molecules. A similar decreasing pattern was observed for the viscosity measured by capillary viscometer with increase in the electrolyte concentration. The hydrodynamic radius of the particles obtained from the dynamic light scattering experiments showed significantly lower values with increment in salt concentration. The decreasing values of these parameters with rise in ionic strength indicate the collapsing of the extended polyelectrolyte chains in presence of salt

    FORMULATION AND EVALUATION OF FLOATING-MUCOADHESIVE MICROSPHERES OF NOVEL NATURAL POLYSACCHARIDE FOR SITE SPECIFIC DELIVERY OF RANITIDINE HYDROCHLORIDE

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    Objective: Localization of ranitidine hydrochloride (RH) into the upper part of the intestinal tract is beneficial for better drug bioavailability. Present work described the method of preparation of novel plant polysaccharide based floating microspheres for delivery of the drug into the stomach. Methods: Polysaccharide was extracted from the seeds of plant Tamarindus indica (TI). Extracted polysaccharide was evaluated for some physicochemical parameters. Floating-mucoadhesive microspheres were prepared by using extracted polysaccharide as mucoadhesive excipients while eudragit as a release controlling polymers by using emulsion crosslinking method. Chemical crosslinking was done by using epichlorohydrin. Prepared microspheres were evaluated for their drug-polymer compatibility study by using fourier transform infrared spectroscopy (FT-IR). Further characterization such as size, surface properties, swelling index, percentage encapsulation, in vitro buoyancy and drug release was performed. Results: FT-IR study confirms the chemical crosslinking of extracted polysaccharide and also drug stability during processing of microspheres. The size of microspheres was in the range of 5.38 to 7.84 µm. SEM images revealed that all batches were of spherical in size and smooth surface. The swelling index showed better swelling in the range of 158-257 percentages. Encapsulation efficiency was found to be decreased by decreasing the concentration of polysaccharide. In vitro buoyancy study possesses that formulation F1 showed better floating ability as compared to the others. Finally, in vitro drug release study revealed that prepared microspheres were able to release the 100% drug within 8-12 h, indicating sustain release behavior. Conclusion: Present study concludes that polysaccharide of TI may be used as excipients for the preparation of floating-mucoadhesive microspheres

    Impact of Shodhana on <em>Semecarpus anacardium</em> Nuts

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    Semecarpus anacardium is classified in Ayurveda under the category of toxic plants. However, this toxic plant is reported to possess anti-inflammatory activity, anti-arthritic effect, antioxidant activity, antimicrobial activity, anti- carcinogenic activity, hypoglycemic activity, cardioprotective, hepatoprotective, neuroprotective, and hypolipidemic activity etc. All these activities are attributed to its various constituents like phenolic compounds, flavonoids, carbohydrates, alkaloids, steroids, etc. In Ayurveda, a series of pharmaceutical procedures which converts a poisonous drug into a safe and therapeutically effective medicine is termed as Shodhana. Shodhana improves the yield, decreases the phenolic and flavonoid content; and converts toxic urushiol into nontoxic anacardol derivative thereby reducing toxicity of nuts of Semecarpus anacardium. There are reports of alteration in pharmacology and phytochemistry of nuts of Semecarpus anacardium due to Shodhana

    Common Bulkhead Tank Design for Cryogenic Stage of an Indian Launch Vehicle

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    Indian Space Research Organization (ISRO) has been advancing in space technology with its cost-effective techniques. Currently, ISRO, in its cryogenic stages, uses truss type intertank structure, which induces large concentrated loads at the truss interfaces. As a remedial measure, works on closed intertank are being carried out by them, but this configuration will considerably increase the launch vehicle mass compared to truss type. Therefore, after a thorough literature survey, a Common bulkhead (CBH) tank seemed to be the best solution to the aforementioned problem. Detailed research on sandwich-type CBH has been carried out in this paper with the motivation of saving mass and height in launch vehicles. Suitable core and facesheet material were selected. A novel foam-filled honeycomb core is suggested in this work. Several comparisons in various CBH dome designs were carried out to reach for the best possible configuration and composition that can be used. MATLAB®, SolidWorks®, and ANSYS® were used in parallel for all computations dealing with design and analysis. A mass saving of approximately upto 490 kgs and a height reduction of upto 1.755 m was obtained with the final selected configuration with respect to the current GSLV configuration. These savings can add extra payload capacity to ISRO launch vehicles in their future missions

    Butea monosperma Reduces Haloperidol and Sulpiride Induced Hyperprolactinemia in Rats

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    Background: Prolonged administration of neuroleptic drugs cause disrupted D dopamine receptor which leads to increased prolactin level, causes gyanaecomastia. Presently, dopamine receptor agonist is the choice of treatment for hyperprolactinemia. Aim and Objectives: The study aims to determine the antihyperprolactinemic effect of methanolic extract of Butea monosperma (MEBM) against haloperidol (HPL) and sulpiride (SPD) induced hyperprolactinemia and to correlate with its active constituents. Material and Methods: To induce hyperprolactinemia HPL 5 mg/kg for 16 continuous days and SPD 20 mg/kg for 28 continuous days was administred. MEBM 200 mg/kg/day and 400 mg/kg/day were administered for 16 and 28 days respectively half an hour before administration of HPL and SPD. The serum prolactin (PRL) level, dopamine (DA) level and antioxidant status in the rat brain, hematological parameters were measured and histological examination of the anterior pituitary gland, adrenal gland and spleen were done. In addition, antioxidant enzymes like superoxide dismutase (SOD) and catalase (CAT) were also estimated. Results: MEBM decreases serum PRL level and increased DA level in brain significantly. Further, MEBM also restored SOD and CAT status significantly. The inflammatory markers induced by HPL and SPD were suppressed by MEBM. Discussion: Neuronal DA inhibition by neuroleptic drugs decreases the release of DA which leads to hyperprolactinemia. MEBM (butrin) may activate DA neurones to ameliorate hyperprolactinaemia. The dopaminergic, anti-oxidant and anti-inflammatory effect of MEBM may be attributed to its anti-hyperprolactinemic effect. Conclusion: Butea monosperma possesses anti-hyperprolactinemic effect which may be attributed to its marker constituent like Butrin

    SYNTHESIS & IN-VITRO PROTEIN DENATURATION SCREENING OF 2-[(1, 5-DISUBSTITUTEDPHENYL-4,5-DIHYDRO-1H-PYRAZOL-3-YL)OXY]BENZOIC ACID DERIVATIVES

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    Abstract Novel 2-[(1,5-diphenyl-4,5-dihydro-1H-pyrazol-3-yl)oxy]benzoic acid (2a) & 2-[5-(2-hydroxyphenyl)-1-Phenyl-4,5-dihydro-1H-pyrazol-3-yl]benzoic acid (2b) were produced and examined for their in-vitro protein denaturation activities. It was discovered that compound 2b showed promise and had more potency than acetylsalicylic acid (NSAID) in inhibiting denaturation of bovine serum albumin. Docking research also supports this. The compound 2b has the highest docking scores with COX1(PDB ID 3N8Z), COX2 (PDB ID 4PH9), and TNF (PDB ID 2AZ5), respectively, of Etotal -233.75, -256.48, and -255.83. TLC and elemental tests were used to determine the compounds' purity. All of the generated molecules' analytical and spectral data (1H NMR, FTIR, and MS) were entirely consistent with the proposed structures

    Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

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    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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