Study of physicochemical properties of flutamide-loaded Ocimum basilicum microspheres with ex vivo mucoadhesion and in vitro drug release

Drug which shows extensive first pass effect is difficult task that, needs to be solved by formulators in the pharmaceutical science. The low oral bioavailability (49%) of flutamide may be due to poor wettability, low aqueous solubility and extensive first pass effect. The aim of present investigation was to prepare flutamide loaded microspheres and incorporate it into suppositories for rectal delivery to avoid first pass effect and enhance residence time. Flutamide loaded mucoadhesive microspheres of Ocimum Basilicum mucilage (OBM) were prepared using spray drying and characterized by percent production yield, encapsulation efficiency, particle size, zeta potential, polydispersity index, DSC, SEM, XRPD, in vitro drug release and stability studies. Moreover, ex vivo mucoadhesion was investigated using falling liquid film technique to determine the adhesion of microspheres to sheep rectal mucosa. The microspheres had nearly spherical shape and size about 2.53?μm. The encapsulation efficiency and mucoadhesion of optimized formulation MBF10 were found to be 69.6?±?2.3% and 89.01?±?2.18%, respectively. Percent CDR of optimized flutamide loaded mucoadhesive microspheres was found to be 88.7?±?1.3 at 7?h. In conclusion, OBM microparticles based suppository could be used to deliver drug through rectal delivery.     

Measurement of Plasma Density in Brass Arc Plasma at Atmospheric Pressure Using a Langmuir Single Probe

In this work, we construct electrodes of brass to produce plasma by arc discharge and is characterized by using a movableLangmuir single probe. It is a simple w...     

Influence of homogeneous‐heterogeneous reactions and induced magnetic field on the nonlinear thermal convective radiative Jeffrey liquid flow with heat source/sink

An analysis has been carried out to investigate the effect of homogeneous‐heterogeneous reactions and induced magnetic field on the unsteady two‐dimensional incompressible nonlinear thermal convective velocity slip flow of a Jeffrey fluid in the presence of nonlinear thermal radiation and heat source/sink. We assumed that the flow is generated due to injection at the lower plate and suction at the upper plate. We obtained a numerical solution for the reduced nonlinear governing system of equations via the shooting technique with fourth‐order Runge‐Kutta integration. We plotted the graphs for various nondimensional parameters, like Deborah number, heat source/sink parameter, nonlinear convection parameter, nonlinear radiation parameter, magnetic Reynolds number, Strommer's number, velocity slip parameter, strengths of homogeneous, heterogeneous reaction parameters and skin friction over the nondimensional flow, temperature, concentration profiles and magnetic diffusivity fields. Also, we calculated the numerical values of boundary properties, such as the skin friction and heat transfer rate. We noticed that the temperature of the fluid is enhanced with the radiation parameter, whereas the concentration decreases with increase of the magnetic Reynolds number. The present results have good agreement with published work for the Newtonian case.     

Simulation of corona discharge. Positive corona in SF6

Positive coronas in SF₆ under three voltage levels, 3.0, 3.5 and 4.0 kV, are studied for a 0.5 cm gap between a hyperboloid needle and a plane electrode at a gas number density N=2.12×10¹⁸ cm³. The current in the form of a burst of pulses is found to increase with increasing voltage. The initiation and development of successive avalanches are traced as function of time after voltage increases. The development of electron avalanches and streamers are due to ionization and photoionization and quenching of avalanches is due to space charge. The simulation provides a detailed structure of avalanches from which essential differences between positive and negative corona with regard to total field distribution, propagation of successive avalanches and ion distribution can be discerned     

Effect of propranolol and nifedipine on maximal electroshock-induced seizures in mice: individually and in combination

To clarify the influence of the head-up position on cerebral oxygen metabolism during laparoscopy with CO2 insufflation in 12 patients who underwent laparoscopic cholecystectomy, changes in the concentrations of cerebral oxyhemoglobin (HbO2), deoxyhemoglobin (Hb), total hemoglobin (total Hb) and oxidized cytochrome aa3 (Cyt aa3) were measured by use of near-infrared laser spectroscopy. Anesthesia was maintained with nitrous oxide (66%), oxygen, and sevoflurane. Pneumoperitoneum was maintained at an intraabdominal pressure of 10-12 mm Hg by use of CO2. Minute ventilation was adjusted to maintain end-tidal CO2 tension (P(ET)CO2) between 35 and 40 mm Hg during the procedure. Patients were moved from supine to the head-up (20 degree) position before intraabdominal manipulation. The concentration of HbO2 decreased significantly when patients were moved to the head-up position and 30 min thereafter. It remained significantly low after they were returned to the supine position and at the end of surgery. The concentration of Hb was unchanged during the study. Therefore, the concentration of total Hb decreased significantly when patients were moved to the head-up position, as well as 30 min thereafter. It remained significantly low after they were returned to the supine position and at the end of surgery. The concentration of Cyt aa3, however, did not change significantly during the study. These results suggest that the head-up position during laparoscopic cholecystectomy decreases cerebral HbO2 and total Hb.     

Coupling finite and boundary element methods for two-dimensional potential problems

A finite-element-boundary-element (FE-BE) coupling method based on a weighted residual variational method is presented for potential problems, governed by either the Laplace or the Poisson equations. In this method, a portion of the domain of interest is modelled by finite elements (FE) and the remainder of the region by boundary elements (BE). Because the BE fundamental solutions are valid for infinite domains, a procedure that limits the effect of the BE fundamental solution to a small region adjacent to the FE region, called the transition region (TR), is developed. This procedure involves a judicious choice of functions called the transition (T) functions that have unit values on the BE-TR interface and zero values on the FE-TR interface. The present FE-BE coupling algorithm is shown to be independent of the extent of the transition region and the choice of the transition functions. Therefore, transition regions that extend to only one layer of elements between FE and BE regions and the use of simple linear transition functions work well.     

LEC18, a dominant Chinese hamster ovary glycosylation mutant synthesizes N-linked carbohydrates with a novel core structure

The dominant Chinese hamster ovary cell glycosylation mutant, LEC18, was selected for resistance to pea lectin (Pisum sativum agglutinin (PSA)). Lectin binding studies show that LEC18 cells express altered cell surface carbohydrates with markedly reduced binding to 125I-PSA and increased binding to 125I-labeled Datura stramonium agglutinin (DSA) compared with parental cells. Desialylated [3H]Glc-labeled LEC18 cellular glycopeptides that did not bind to concanavalin A-Sepharose exhibited an increased proportion of species that were bound to DSA-agarose. Most of these glycopeptides bound to ricin-agarose and were unique to LEC18 cells. This fraction was purified from approximately 10(10) cells and shown by 1H NMR spectroscopy and methylation linkage analysis to contain novel N-linked structures. Digestion of these glycopeptides with mixtures of beta-D-galactosidases and N-acetyl-beta-D-glucosaminidases gave core glycopeptides that, in contrast to cores from parental cells, were mainly not bound to concanavalin A-Sepharose or to PSA-agarose. 1H NMR spectroscopy, matrix-assisted laser desorption ionization/time of flight mass spectrometry, electrospray mass spectrometry, and collision-activated dissociation mass spectrometry showed that the LEC18 core glycopeptides contained a new GlcNAc residue that substitutes the core GlcNAc residues. Methylation linkage analysis of the parent compound provided evidence that the GlcNAc is linked at O-6 to give the following novel, N-linked core structure. [formula: see text]     

Study of in vivo tumor state and response to therapy by analysis of DNA distribution

Comparative studies of cefamandole and cephalothin were carried out in 32 cancer patients. After rapid intravenous injection of 1 gm cefamandole or cephalothin, the peak mean serum concentrations in 11 patients achieved at 0.25 hr were 103.4 mcg/ml and 56.7 mcg/ml, respectively. Except at 6 hr, the serum concentration of cefamandole was higher (p less than 0.05) at all times. The terminal half-lives (t 1/2) were similar, being 1.2 hr for cefamandole and 1.0 hr for cephalothin. Cefamandole, 1 gm intramuscularly, induced a peak mean serum concentration of 26.6 mcg/ml at 1 hr, with a slow decay. Intermittent cefamandole (2 gm intravenously every 6 hr) induced very high mean serum concentrations (7 patients), but at 4 hr the concentrations were similar to those after 1 gm intravenously. Per cent of urinary excretion was similar for both drugs regardless of dose and mode of administration. Continuous-infusion cefamandole or cephalothin (2 gm loading followed by 2 gm every 6 hr) in 14 patients showed consistently higher serum concentrations for cefamandole (p less than 0.05) over a 5-day period. There was no evidence of drug accumulation in the multiple-dose studies. Both the single- and multiple-dose schedules were well tolerated.     

Exposure to enriched environment improves spatial learning performances and enhances cell density but not choline acetyltransferase activity in the hippocampus of ventral subicular-lesioned rats.

The authors demonstrated the efficacy of enriched housing conditions in promoting the behavioral recovery and neuronal survival following subicular lesion in rats. Chemical lesioning of the ventral subiculum impaired the spatial learning performances in rats. The lesion also induced a significant degree of neurodegeneration in the CA1 and CA3 areas of the hippocampus and entorhinal cortex. Exposure to enriched housing conditions improved the behavioral performance and partially attenuated the neurodegeneration in the hippocampus. The choline acetyl transferase (ChAT) activity in the hippocampus remained unchanged following ventral subicular lesion and also following exposure to an enriched environment. The study implicates the effectiveness of activity-dependent neuronal plasticity induced by environmental enrichment in adulthood following brain insult. (PsycINFO Database Record (c) 2010 APA, all rights reserved)