48 research outputs found

    Formulation and Evaluation of Bilayer Floating Tablets

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    The aim of the present study is to formulate and evaluate the bilayer tabletsof Atorvastatin and Ramipril using different media, to know the releasestudies in which media the release of the drug is in controlled manner. Thebilayer tablets of Atorvastatin matrix floating and Ramipril immediaterelease tablets were prepared. Bi-Layer tablets consists of two layersi.e.,immediate release layer containing of disintegrant sodium starchglycollate and controlled release layer containing HPMCK100M, POLY0XWSR 303 and sodium alginate asretard layer. Combination of Atorvastatinand ramipril prepared by direct compression and wet granulation methodwhich consists of various disintegrants and polymer in different ratios Thetablets were evaluated for various parameters like weight variation,thickness, hardness and friability. The release studies were carried out usingdifferent media using USP dissolution testing apparatus II (paddle type) for12hr

    Formulation Design And Characterization Of Matrix Tablets

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    The aim of this study was to design oral controlled release lamivudine matrix tablets using hydroxypropyl methylcellulose (HPMC) as the retardant polymer, sodium alginate, acacia gum to study the effect of various formulation factors such as polymer proportion, polymer viscosity, and compression force on the in vitro release of drug. In vitro release studies were performed using (USP II) with paddle apparatus (basket method) in 900 mL of pH 6.8 phosphate buffer at 50 rpm. The release kinetics were analyzed using the zero-order model equation, Higuchi’s square-root equation, and the Ritger-Peppas empirical equation. Compatibility of the drug with various excipients was studied. Increase in compression force was found to decrease the rate of drug release. Methematical analysis of the release kinetics indicated that the nature of drug release from the matrix tablets was dependent on drug diffusion and polymer relaxation and therefore followed non-Fickian or anomalous release. No incompatibility was observed between the drug and excipients used in the formulation of matrix tablets. The developed controlled release matrix tablets of lamivudine, with good initial release (32% in 4th hour) and extension of release up to 14 hours, can overcome the disadvantages of conventional tablets of lamivudin

    A REVIEW ON DISINTEGRATION CONTROL MATRIX TABLETS

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    A number of sustained release formulations are available in the market which successfully sustained the drug release over a prolonged period of time by different mechanisms. The new approach for sustaining the drug release is disintegration control matrix tablet which sustained the drug release up to 24hrs by controlling the disintegration rate of tablet. Disintegration control matrix tablet (DCMT) mainly forms the granules containing drug and disintegrating agent such as low substituted hydroxyl propyl cellulose by various methods such as solid dispersion technique. The sustained release of drug is maintained by increasing the wax coating or decreasing the amount of disintegrants. The release of drug from tablet is uniform throughout till all the drug releases from tablet as it involves drug release by diffusion, dissolution and surface erosion mechanism. DCMT increases the solubility of drug and improves the bioavailability without disturbing gastrointestinal transit. BCS Class II, III, IV drugs are the best candidate for DCMT formulations. Keywords: Disintegration control matrix tablet (DCMT), Wax, Disintegrating agent, Solid dispersion

    Nanosuspensions as a promising approach to enhance bioavailability of poorly soluble drugs : An update

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    Solubility is a vital factor for devloping drug delivery systems for poorly water soluble drugs. Several conventional approaches for enhancement of solubility have limited applicability, especially when the drugs are poorly water soluble. Nanosuspension technology can be used to enhance the solubilty, stability as well as the bioavailability of poorly water soluble drugs. Nanosuspensions are biphasic systems comperising of pure drug particles dispersed in an aqueous vehicle, stabilized by surfac active agents. Fabrication of nanosuspension is simple and more advantageous than other approaches. Techniques like high-pressure homogenization, wet milling, emulsification, solvent evaporation, bottom up technology and top down technology have been applicable in the fabrication of nanosuspensions. Nanosuspension delivery is possible by several routes, such as oral, pulmonary, parenteral and ocular routes. Nanosuspension not only solves solubility and bioavailability issue, but improve drug safety and efficacy. In this context, we reviewed the current techniques used to develop nanosuspensions and their recents studies application in drug delivery system. Keywords : Solubility, fabrication, Characterization, Applications, Nanosuspension

    Genome-wide association of white blood cell counts in Hispanic/Latino Americans: the Hispanic Community Health Study/Study of Latinos

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    Circulating white blood cell (WBC) counts (neutrophils, monocytes, lymphocytes, eosinophils, basophils) differ by ethnicity. The genetic factors underlying basal WBC traits in Hispanics/Latinos are unknown. We performed a genome-wide association study of total WBC and differential counts in a large, ethnically diverse US population sample of Hispanics/Latinos ascertained by the Hispanic Community Health Study and Study of Latinos (HCHS/SOL). We demonstrate that several previously known WBC-associated genetic loci (e.g. the African Duffy antigen receptor for chemokines null variant for neutrophil count) are generalizable to WBC traits in Hispanics/Latinos. We identified and replicated common and rare germ-line variants at FLT3 (a gene often somatically mutated in leukemia) associated with monocyte count. The common FLT3 variant rs76428106 has a large allele frequency differential between African and non-African populations. We also identified several novel genetic loci involving or regulating hematopoietic transcription factors (CEBPE-SLC7A7, CEBPA and CRBN-TRNT1) associated with basophil count. The minor allele of the CEBPE variant associated with lower basophil count has been previously associated with Amerindian ancestry and higher risk of acute lymphoblastic leukemia in Hispanics. Together, these data suggest that germline genetic variation affecting transcriptional and signaling pathways that underlie WBC development and lineage specification can contribute to inter-individual as well as ethnic differences in peripheral blood cell counts (normal hematopoiesis) in addition to susceptibility to leukemia (malignant hematopoiesis)

    Cyclodextrin Complexes of Reduced Bromonoscapine in Guar Gum Microspheres Enhance Colonic Drug Delivery

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    Here, we report improved solubility and enhanced colonic delivery of reduced bromonoscapine (Red-Br-Nos), a cyclic ether brominated analogue of noscapine, upon encapsulation of its cyclodextrin (CD) complexes in bioresponsive guar gum microspheres (GGM). Phase−solubility analysis suggested that Red-Br-Nos complexed with β-CD and methyl-β-CD in a 1:1 stoichiometry, with a stability constant (Kc) of 2.29 × 103 M−1 and 4.27 × 103 M−1. Fourier transforms infrared spectroscopy indicated entrance of an O−CH2 or OCH3−C6H4−OCH3 moiety of Red-Br-Nos in the β-CD or methyl-β- CD cavity. Furthermore, the cage complex of Red-Br-Nos with β-CD and methyl-β-CD was validated by several spectral techniques. Rotating frame Overhauser enhancement spectroscopy revealed that the Ha proton of the OCH3−C6H4−OCH3 moiety was closer to the H5 proton of β-CD and the H3 proton of the methyl-β-CD cavity. The solubility of Red-Br-Nos in phosphate buffer saline (PBS, pH ∼ 7.4) was improved by ∼10.7-fold and ∼21.2-fold when mixed with β-CD and methyl-β-CD, respectively. This increase in solubility led to a favorable decline in the IC50 by ∼2-fold and ∼3-fold for Red-Br-Nos−β-CD-GGM and Red-Br-Nos−methyl-β-CD-GGM formulations respectively, compared to free Red-Br-Nos−β-CD and Red-Br-Nos−methyl-β-CD in human colon HT-29 cells. GGM-bearing drug complex formulations were found to be highly cytotoxic to the HT-29 cell line and further effective with simultaneous continuous release of Red-Br-Nos from microspheres. This is the first study to showing the preparation of drug-complex loaded GGMS for colon delivery of Red-Br-Nos that warrants preclinical assessment for the effective management of colon cancer

    Track D Social Science, Human Rights and Political Science

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

    Dual pathology causing severe pulmonary hypertension following surgical repair of total anomalous pulmonary venous connection: Successful outcome following serial transcatheter interventions

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    Surgical repair of total anomalous pulmonary venous connection (TAPVC) can be complicated by the development of pulmonary venous stenosis later on. In addition, the vertical vein, if left unligated, can remain patent and lead to hemodynamically significant left to right shunting. We report an infant who required transcatheter correction of both these problems after surgical repair of TAPVC
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