Fabrication and Catalytic Characterization of Laccase-Loaded Calcium-Alginate Beads for Enhanced Degradation of Dye-Contaminated Aqueous Solutions

Catalysis Letters - Engineered laccases represent an eco-friendlier and robust biocatalytic tool for the treatment of dye-harboring textile wastewater. This study investigates the immobilization of...     

The response of addult rats to varying combinations of dietary lysine and threonine

The response of adult rats fed diets containing amino acid mixtures with varying combinations of lysine and threonine was studied by estimating the change in body weights, organ weights, total nitrogen content of organs and the concentration of free plasma lysine and threonine. Analysis of variance indicates a significant effect of threonine, lysine and a significant interaction due to feeding the two amino acids on the body weights, organ weights and total nitrogen content of various organs. Significant effect on the level of the plasma free amino acid was also shown as a result of feeding the particular amino acid. Results show that in deficient animals the rates of building body protein are low but are higher in the lysine deficient animals than in the threonine deficient and protein deficient animals. The varying rates of exchanging protein between the various organs in response to changing the levels of amino acids in the diet would mean that total change in body protein or total nitrogen balance may not be satisfactory way to determine the protein or amino acid requirements for maintenance. It seems to be necessary to focus down on protein turnover rates in specific tissues.     

Sustained Release Matrix of Mebeverine Hydrochloride Using Polyacrylate Resin “Eudragit Retard” Kinetic of Drug Release and Evaluation of a Kinetic Model

In this study Eudragit RS PM and RL PM were evaluated as carriers for the preparation of prolonged release solid dispersions of mebeverine hydrochloride by solvent and melting methods. The prepared tablets were examined for dissolution at pH 1.2 and 7.4, Eudragit RS PM and RL PM were found satisfactory as potential slow release carriers. The solid dispersion prepared by the solvent method showed a slow release pattern. Drug release appeared to fit both, first order and Higuchi matrix model kinetics. However, on application of the differential rate treatments, the evidence supported the Higuchi matrix model. Effect of temperatures on dissolution rate was studied for thermodynamic consideration.

The drug release was pH-independent until pH 7.4.As the pH increased, the release was significantly reduced due to solubility problem.     

Combined site-specific release retardant mini-matrix tablets (C-SSRRMT) for extended oral delivery of dexketoprofen trometamol: in vitro evaluation and single versus multiple doses pharmacokinetic study in human volunteers

Abstract

Development of extended release oral formulations of dexketoprofen trometamol (DT), a rapidly eliminated drug with high solubility, poses a great challenge especially when a portion of the dose is to be absorbed from the colon. In this study, site-specific release-retardant mini-matrix tablets (SSRRMTs) were developed and functionally coated with pH-responsive materials to achieve a site-specific delivery of DT at the duodenojejunal (DSRRMT) and ileocecal (ISRRMT) regions. Stomach-specific coated mini-tablets (SSCMTs) were manufactured for immediate release of about 16% of the daily dose of DT in the stomach. The SSCMT, DSRRMT, and ISRRMT were combined into a solid dosage form (C-SSRRMT tablets or capsules) to achieve the required linear release profile for once daily administration of DT. The SSRRMT and C-SSRRMT formulations were evaluated for the physical properties, in vitro-disintegration and in vitro dissolution and proved to be consistent with the pharmacopeial specifications. The in vitro release profiles of both C-SSRRMT tablets and capsules showed a constant release rate of about 6?mg/h and were similar to that of the theoretical target linear release profile. The pharmacokinetic study using human volunteers showed the bioequivalence of a single oral dose of C-SSRRMT capsules compared to three-successive oral doses of the immediate release market tablets with less ups and downs in the drug levels. The C-SSRRMT capsules formulation, may therefore, constitute an advance in the extended oral delivery of DT without the lack of efficacy and the adverse events frequently encountered in multiple daily dosing of the immediate release tablets.     

Evaluation of curing and physical properties of NR/SBR blends using radiation-grafting copolymer

The curing characterizations of natural rubber (NR) and styrene butadiene rubber (SBR) lattices and their blends with and without NR-g-MA and SBR-g-MA were studied by using oscillating disc rheometer methods. The minimum value for torque decreases with increasing NR in the blends and with the incorporation ofNR-g-MA and SBR-g-MA. The value of maximum torque increases with increasing of SBR in the blend and with the presence of (NR-g-MA and SBR-g-MA) is decreased. The mechanical properties of the samples were studied. The tensile strengths increased steadily with an increase of NR content in the blend. Thermal characteristics of these latex blends were studied by thermogravimetric analysis. Thermal degradation of these individual lattices and their blends were investigated with special reference to blend ratio and vulcanization techniques. As the SBR content in the blends increased their thermal stability was also found to increase. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers     

Functional role of bioactive peptides with special reference to cheeses

Growing perception about diet in relation to health has extended the necessity to explore the biologically active components present in native foods. In this review, bioactive peptides released from cheeses that may have important physiological functions are discussed. Bioactive encrypted peptides can be generated from precursor milk proteins during food processing via enzymatic hydrolysis and fermentation. Generally, biofunctionalities of peptides are latent within precursor proteins. Bioactive peptides liberated from cheeses exhibit numerous potential therapeutic roles: for example, angiotensinogen‐converting enzyme (ACE) inhibition, antioxidant, anti‐thrombotic, anti‐microbial, anti‐cancer and anti‐inflammatory. This article critically focuses on the functional roles of bioactive peptides derived from different cheeses.     

AIDS prevention strategies for ethnic-racial minority substance users.

African Americans and Latinos account for 29% and 16%, respectively, of persons with AIDS, yet collectively represent less than 20% of the US population. Although rates of HIV transmission have slowed among gay Anglo men, there is less evidence to indicate that patterns of transmission have been altered among Black and Hispanic drug users. Risk factors for HIV transmission among drug users are described, and sociocultural aspects of these risk behaviors are discussed. The advantages and disadvantages of various approaches to reducing the spread of HIV among drug users and their associates are considered, particularly as they apply to ethnic–racial minorities. Brief examples are provided of how existing theories of behavior change can be applied in Hispanic and African-American communities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Variation of the specific surface area and porosity of anhydrous zinc oxalate with water vapour pressure

Specific surface areas and pore structure studies were carried out on two sets of samples of anhydrous zinc oxalate prepared from the dihydrate by heating at 130 and 180°C in various atmospheres of differing water vapour pressure. The two sets of samples were freshly prepared and aged samples. The variation of specific surface areas with water vapour pressure was found to behave in accordance with the Smith-Topley effect, with a minimum S_BET value located at 3.0 mmHg of water vapour. Analysis of the nitrogen adsorption isotherms by the t-method revealed the existence of both micropores and mesopores in the freshly prepared samples heated both at 130 and 180°C in 8.0 mmHg water vapour, and also in the aged samples prepared at 130°C in vacuo, and at 180°C in 8.0 mmHg water vapour. The rest of the samples possess only wide pores. Complete pore structure analysis for both micro- and mesopores was carried out for all samples investigated, and an attempt was made to correlate the factors affecting the development of surface area and pore structure, both in the presence and absence of water vapour, with those affecting the dehydration rate, and which occasionally lead to the Smith-Topley effect.     

Context-aware negotiation,reputation and priority traffic light management protocols for VANET-based smart cities

Telecommunication Systems - The traditional transportation system is based on a fixed-timed strategy to control the traffic congestion on urban roads. However, the increase of vehicle density in a...     

Hybrid Wireless Sensors Deployment Scheme with Connectivity and Coverage Maintaining in Wireless Sensor Networks

With the rapid growth of the internet of things (IoT), an impressive number of IoT’s application based on wireless sensor networks (WSNs) has been deployed in various domain. Due to its wide ranged applications, WSNs that have the capability to monitor a given sensing field, became the most used platform of IoT. Therefore, coverage becomes one of the most important challenge of WSNs. The search for better positions to assign to the sensors in order to control each point of an area of interest and the collection of data from sensors are major concerns in WSNs. This work addresses these problems by providing a hybrid approach that ensures sensors deployment on a grid for targets coverage while taking into account connectivity. The proposed sequential hybrid approach is based on three algorithms. The first places the sensors so as to all targets are covered. The second removes redundancies from the placement algorithm to reduce the number of sensors deployed. The third one, based on the genetic algorithm, aims to generate a connected graph which provide a minimal path that links deployed sensors and sink. Simulations and a comparative study were carried out to prove the relevance of the proposed method.