DEVELOPMENT AND CHARACTERIZATION OF GASTRO RETENTIVE MUCOADHESIVE MICROBEADS CONTAINING SIMVASTATIN WITH DIFFERENT CROSS LINKING AGENTS

Objective: The aim of the present work was to prepare and examine drug release of the oral controlled release microbeads using different curing agents by emulsification internal ionic gelation technique. Methods: Cross-linked alginate microbeads were prepared with different cross linking agents by using mucoadhesive properties. The formation and compatibility of microbeads were confirmed by compatibility studies. Prepared microbeads evaluated for encapsulated efficiency, micromeritic properties, drug loading, in vitro wash off studies, in vitro dissolution studies, drug release kinetics and stability studies Results: The in vitro drug release was influenced by both type of curing agents and type of polymers and no significant changes in characterization parameters was observed after 3 mo stability studies. The sustained release profile of optimized batch was found to be 99.66±0.18% in comparison to pure drug profile of 28.64±0.02% at 12 h release study. Results of both wash-off and in vitro studies suggests that batch (SF2) prepared with aluminium chloride has shown better mucoadhesive property. Drug release of optimized batch follows zero order with non fickian mechanism according to Korsmeyer-Peppas equation. Conclusion: The data suggest the use of simvastatin mucoadhesive cross linked microbeads to offer the potential for oral controlled drug delivery with improved gastric retention and capable to provide sustained drug release by using cross linking agents

Insights into improved ferroelectric and electrocaloric performance of Ba0.85Ca0.15Ti0.9Zr0.1O3 thick films grown by the electrophoretic deposition

Lead-free Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCZT) bulk ceramics have recently gained attention as one of the attractive candidates for electrocaloric cooling due to their large heat absorption capacity induced by electro-structural phase transition near room temperature. However, adiabatic temperature change (ΔT) at room temperature in ceramics has been limited by their relatively low dielectric breakdown strength. Thick films, in this respect, possess the advantages of ceramics (volume) and thin films (thickness). In this work, a systematic ferroelectric and electrocaloric investigation of BCZT thick films, fabricated by electrophoretic deposition combined with laser annealing, has been carried out. Laser annealing at an optimized energy density of 398 W/cm2 has resulted in densely packed grain morphology with no compositional heterogeneities. Analysis of the scaling behavior of dynamic hysteresis revealed that ferroelectric domain reversal in BCZT/Pt has good stability and low energy consumption in the saturation region. The present thick films exhibited larger breakdown strength of 294 kV/cm and recoverable energy storage density of ~7.3 J/cm3 , at least five-fold enhancement compared to the bulk which is stable up to a 4 mm bending radius. The indirect electrocaloric measurements displayed parameters such as a ΔT and entropy change (ΔS) of 2.94 K and 3.1 J kg− 1 K− 1 respectively, for 205 kV/cm which are more than two orders increased compared to the bulk. Higher values of ΔT (1.9 K) at 25 ◦C, refrigerant capacity of 249 J/kg, and responsivity of 0.143 K mm/kV for BCZT/Pt film compared to relevant lead-free ferroelectric thick films elucidate the potential use of these films for solid-state refrigeration applications. The work also presents electrophoretic deposition with laser annealing as an alternative technique to widely studied tape-casting of thick films for electrocaloric studies.publishe

Panorama of neoplasms of upper GI tract: a 5 year research study

Background: The diseases of the gastrointestinal tract (GIT) are the most common and leading cause of morbidity and mortality than the disorders of any other systems of the body. Gastrointestinal (GI) tract tumors are one of the most common cancers accounting for 11% of all cancers. Among these tumors, upper gastrointestinal tract malignancies are quite aggressive with a dismal prognosis. Malignant tumors are most common than benign. The most common carcinoma of the esophagus is Squamous cell carcinoma (SCC). Incidence of SCC is less than 5 per 100,000 populations in males and 1 per 100,000 populations in females. Gastric cancer was the second most common cancer in the World and 60% of them occurred in developing countries. The most common carcinoma of the Stomach is Adenocarcinoma.Aim & Objectives: To study the spectrum of neoplastic lesions of the upper gastrointestinal tract by the examination of endoscopic biopsies and surgically resected specimens. To determine the degree of severity of the malignancies by assessing the depth of invasion, Lymph nodal & Omental spread.Methods: The present study is both retrospective & prospective study for a period of 5 years from January 2007 to December 2011. The sample size includes all the endoscopic biopsies & surgically resected specimens of gastrointestinal tract received at Department of Pathology, S.V. Medical College, Tirupati. The study also obtained clearance from the ethical committee of the institution. The biopsy specimens thus obtained were fixed in 10% buffered neutral formalin. The sections were stained routinely with H & E. Special stains and IHC done wherever necessary.Results: we have received 120 specimens regarding the upper gastrointestinal system. Among these 120 specimens, 71 specimens were endoscopic biopsies & 49 specimens were surgically resected specimens. Out of 71 Endoscopic biopsies 28 biopsies were malignant among which 2 was esophagus and 26 were stomach. Out of 49 surgically resected specimens 1 was benign and 32 were malignant tumors. Out of 59 neoplasms of stomach there were single cases each of Sub mucosal Lipoma, Malignant lymphoma, GIST & 56 cases of Adenocarcinoma & its variants were noted.Conclusion: Most of the neoplasms are of stomach (97%). All the neoplasms are malignant except one benign lesion sub mucous lipoma of stomach. Most of the neoplasms of stomach were Adenocarcinoma (96.5%). Both tumors of esophagus were squamous cell carcinoma occurred after 50 years of age.

Study of various congenital anomalies in fetal and neonatal autopsy

Background: The study of dead is to save the livings. The growing awareness that still births and infant mortalities are unable to reduction has led to a wide spread desire for more information regarding the cause of these deaths. Congenital malformations have become important cause of fetal and neonatal (perinatal) mortality in developed countries and would very soon be increasingly important determinants of fetal and neonatal mortality in developing countries like India. In spite of antenatal diagnostic modality still the fetal autopsy plays the vital role in the conformation as well as identification of congenital anomalies and also for the counseling of the parents, to prevent the fetal congenital anomalies in further pregnancies. This study was undertaken with the purpose of finding out cause of death during the perinatal period at government maternity hospital and pediatric department S.V.R.R.G.G.H. & S.V. medical college Tirupati, and to study the clinical and pathological findings (Gross & microscopic) in fetal and neonatal death.Methods: The present study of congenital anomalies in fetal and neonatal deaths was done at S.V. medical college, Tirupati, over a time period of 2 years from September 2008 to 2010 August. Consent for autopsy in requested compassionately, respectfully and fully informed. The present study included dead fetus and neonates with gestational age above 20 weeks of intra uterine life and within 7 days of post natal life. All fetuses of gestational age <20 weeks and all neonates above 7 days of age were excluded from the study. The study also obtained clearance from the ethical committee of the institution. Autopsy was performed by standard technique adopted by Edith L. Potter. External and internal findings followed by histopathological examination, and autopsy findings were compared with available ultrasound findings.Results: A total of 46 Autopsies performed, 40 (87%) were fetal deaths, 6 (13%) were early neonatal deaths. In a total of 46 fetuses, there were 13 male and 33 female babies. On external examination of 46 fetal and Neonatal (perinatal) deaths, 8 (17.39%) babies showed congenital malformation. On internal examination of the 46 fetal and Neonatal (perinatal) deaths, 4 babies showed internal congenital anomalies. A total of 46 anatomical and histopathologic examinations were done among fetal and neonatal (perinatal) deaths. Out of 13 autopsies on male babies, 2 had congenital malformation and 33 autopsies on female babies, 7 had congenital malformations. Congenital anomalies were commonest in the birth weight group of 1000-1500 grams accounting for 9 cases. Malformations of central nervous system (33.33%) were most common followed by musculoskeletal system (16.66%), genitourinary and respiratory system (8.33%) respectively.Conclusion: Most number of perinatal deaths occurred in low birth weight and preterm babies. Study of malformations greatly helpful in genetic counseling and prenatal diagnosis in successive pregnancies

DEVELOPMENT, CHARACTERIZATION AND ANTIBACTERIAL PROPERTIES OF SILVER NANOPARTICLES LOADED SODIUM ALGINATE/XANTHAN GUM MICROBEADS FOR DRUG DELIVERY APPLICATIONS

Objective: The aim of this study is to create pH-responsive drug carriers, which are useful because they have the potential to improve treatment efficacy by controlling the release rate of ofloxacin from the polymer matrix. Methods: In the first step, silver nanoparticles (Ag NPs) were synthesized from silver nitrate using leaf extract of Phyllanthus urinaria L as a reducing agent. In the second step, Ag-NPs-loaded polymeric microbeads were synthesized using sodium alginate (SA) and xanthan gum (XG) for controlled release of ofloxacin (OFLX). The developed microbeads were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (X-RD), transition electron microscopy (TEM), Selected Area Electron Diffraction (SAED), and scanning electron microscopy (SEM). Swelling and in vitro release studies were performed at pH 2.0 and 7.4 at 37 oC. The in vitro antibacterial activity of microbeads were tested against S. mutans, K. pneumoniae, and B. subtilis. The release kinetics and mechanism were analyzed by fitting the release data into different kinetic models and the Korsmeyer-Peppas equation. Results: FTIR confirms the generation of silver nanoparticle and also the generation of polymeric microbeads. SEM studies reveal the developed microbeads are spherical in shape with rough surfaces. TEM studies reveal the size of 20-40 nm. XRD analysis reveals the molecular dispersion of DOX and the presence of silver nanoparticles in the polymeric matrix. Investigations of in vitro release and swelling studies show that the developed microbeads are relatively suitable for intestinal drug delivery because higher release rate was observed at pH 7.4. The developed microbead follows non-Fickian diffusion drug release mechanism. The created samples exhibited antimicrobial activity against S. mutans, K. pneumoniae, and B. subtilis. Conclusion: The results indicate that microbeads containing OFLX and silver nanoparticles are effective drug-delivery vehicles. A further warrant is required for the use of manufactured microbeads in drug delivery applications

Influence of magnetic field location on the heat transfer and friction factor of CoFe2O4-BaTiO3/EG hybrid nanofluids in laminar flow: an experimental study

This report describes the heat transfer and friction factor characteristics of CoFe2O4-BaTiO3/ethylene glycol hybrid nanofluids flow in a tube with and without a magnetic field. The CoFe2O4 and BaTiO3 nanoparticles were synthesized by the sol–gel method individually and then ball-milled to form 35:65% (in mol.) composite hybrid nanoparticles. Structure, morphology, and size were characterized by x-ray diffraction and transmission electron microscope. Temperature-dependent magnetization was studied by a vibrating sample magnetometer. The stable ethylene glycol-based hybrid nanofluids were prepared and the heat transfer and friction factor experiments were conducted in the following parameters: 248.03 < Re < 1995.43; 0 <ϕ < 1.0%; and 0 < Gauss < 4000, respectively. The magnetic field is applied at different places with x/d (distance/diameter) of 30, 60, and 90, respectively. It was found that the Nusselt number is raised by 22.19% at 1.0% vol. of nanofluid and at a Reynolds number of 1240.15, with a penalty in friction factor of 21.88%, against base fluid data without magnetic field. The Nusselt number is further raised by 68.95% and 72.33%, respectively, for 1.0% vol. of nanofluid with magnetic field ( B →) of 1600 G and 4000 G, compared to the base fluid. Under the magnetic field of 4000 G and for 1.0% vol. of nanofluid, the Nusselt number is improved by 41.03%, 35.14%, and 25.94% at different places of x/d of 30, 60, and 90, respectively, as compared to the absence of magnetic field. The results are further showed that at location of x/d of 30 under magnetic field of 4000 G, the greatest Nusselt number had been attained. With the magnetic field of 4000 G and at 1.0% vol. of nanofluid, the friction factor is further enhanced to 68.75%, compared to without magnetic field.publishe

Ultrasonic studies on dilute solutions of water in <i>n</i>-alcohols and 2-alkoxyethanols

259-264Ultrasonic velocities in dilute solutions of water in n-alcohols (methanol, ethanol, n-propanol and n-butanol), and 2-alkoxyethanols (2-methoxyethanol, 2-ethoxyethanol and 2-butoxyethanol) have been determined at 298.15 K using single crystal variable path interferometer working at 3 MHz. The excess ultrasonic velocities have been evaluated using the formula, which is thermodynamically valid. A distinctive non-linear variation of ultrasonic velocity with concentration of water in both n-alcohols and 2-alkoxyethanols has been observed over a small range of concentration. A similar behaviour is also observed in the concentration dependence of excess ultrasonic velocity in these solutions. This behaviour has been explained by considering the existence of water molecules as monomers up to certain optimum concentration, (X2)opt, of water and the non-linear behaviour observed beyond (X2)opt has been explained in the light of water-water and water-alcohol interactions leading to the formation of islands of water-alcohol extended structures

Ultrasonic studies in dilute solutions of water and nonelectrolytes

10-14<span style="font-size:16.0pt;mso-bidi-font-size: 11.0pt;line-height:115%;font-family:" times="" new="" roman";mso-fareast-font-family:="" "times="" roman";color:black;mso-ansi-language:en-in;mso-fareast-language:="" en-us;mso-bidi-language:hi"="" lang="EN-IN">Ultrasonic velocities in dilute solutions of water in n-propanol, isopropanol<span style="font-size:16.0pt; mso-bidi-font-size:11.0pt;line-height:115%;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";mso-ansi-language:en-in;mso-fareast-language:="" en-us;mso-bidi-language:hi"="" lang="EN-IN">, glycerol, formamide. N-methyl formamide, dimethyl formamide tetrahydrofuran and propylene glycol have been determined 298.15 K using single crystal variable path interferometer working at 3 Mhz. Excess sound velocities, have been evaluated using the formula which is thermodynamically valid. Both the ultrasonic velocity and excess ultralsonic velocity have been found to vary nonlinearly with concentration in the high dilution range of water in non electrolytes studied. The results are explained by considering the existence of water molecules <span style="font-size:15.5pt;mso-bidi-font-size:10.5pt;line-height:115%;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";color:black;="" mso-ansi-language:en-in;mso-fareast-language:en-us;mso-bidi-language:hi"="" lang="EN-IN">as monomer up to certain optimum concentration (X2)opt of water and the nonlinear behaviour observed beyond<span style="font-size:12.5pt;mso-bidi-font-size:7.5pt;line-height:115%;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";color:black;="" mso-ansi-language:en-in;mso-fareast-language:en-us;mso-bidi-language:hi"="" lang="EN-IN"> <span style="font-size:15.5pt;mso-bidi-font-size:10.5pt;line-height:115%; font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-IN">(X2)opt <span style="font-size: 16.0pt;mso-bidi-font-size:11.0pt;line-height:115%;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";color:black;mso-ansi-language:en-in;="" mso-fareast-language:en-us;mso-bidi-language:hi"="" lang="EN-IN">has been explained in the light water-water and water- nonelectrolyte interactions leading to the formation of island of water-nonelectrolyte complexes.</span

Effect of mixed electrolytes on the temperature of sound velocity maximum of water

827-832Effect of mixed electrolytes (KCl + KBr), (KCl + KI) and (KBr + KI) on the temperature of sound velocity maximum (TSVM) of water, Tw, has been studied by determining the ultrasonic velocity with an accuracy of ± 0.003% using single crystal variable path interferometer working at 3 MHz. The velocity measurements were carried out at ; 2°C intervals over a range of 5°C on either side of TSVM of the solution. The accuracy in fixing TSVM is ± 0.2°C. The structural contribution to the shift in Tw of pure water due to the addition of mixed electrolytes, Tstr, has been found to be negative and increasing with concentration of mixed electrolytes. At any given concentration Tstr of (KCl + KBr) > (KCl + KI) > (KBr + KI). Tstr is also found to vary linearly with ionic strength of the mixed electrolyte solutions, and at any given ionic strength Tstr of (KCl + KBr) > (KCl + KI) > (KBr + KI). The results are explained in terms of enhancement in the structure breaking nature of Cl-, Br- and I- due to K+ and is found to be in the order of I- > Br- > Cl-