Design and evaluation of 1- and 3-layer matrices of verapamil hydrochloride for sustaining its release

The present study was performed to design oral controlled delivery systems for the water-soluble drug, verapamil hydrochloride, using natural and semisynthetic polymers as carriers in the forms of 1- and 3-layer matrix tablets. Verapamil hydrochloride 1-layer matrix tablets containing hydroxypropylmethylcellulose, tragacanth, and acacia either alone or mixed were prepared by direct compression technique. 3-layer matrix tablets were prepared by compressing the polymers as release retardant layers on both sides of the core containing the drug. The prepared tablets were subjected to in vitro drug release studies. Tragacanth when used as the carrier in the formulation of 1- and 3-layer matrices produced satisfactory release prolongation either alone or in combination with the other 2 polymers. On the other hand, acacia did not show enough prolonging efficiency in 1- and 3-layer matrix tablets. The results also showed that the location of the polymers in the 3-layer tablets has a pronounced effect on the drug release. Kinetic analysis of drug release from matrices exhibiting sustained release indicated that release was predominantly attributable to the contribution made by Fickian diffusion, while the erosion/relaxation mechanisms had a minor role in the release. Published: December 7, 2005     

Parasitoid complex of the pistachio twig borer moth,Kermania pistaciella,in Iran

The parasitoid complex of the pistachio twig borer moth, Kermania pistaciella Amsel (Lepidoptera: Tineidae), a native pest of pistachio trees, was investigated at 27 pistachio plantation sites in Kerman province, the major pistachio growing area of Iran. The present study was conducted to document the naturally established parasitoid complex and to assess the need for improving the biological control of this species. In total, 22,390 moth cocoons were collected from 186 samples collected from commercial orchards during 2006–2008 and kept singly in controlled conditions to rear immature insects. An average of 2.8% of moth cocoons had been attacked by predators at time of sampling. Of the collected cocoons, on average 46.7% completed development and emerged as adult moths, no insects emerged from 8%, suggesting that the moth or wasp died before maturing, and parasitoids emerged from the remaining 42.5%. The overall percentage of host cocoons from which wasps emerged ranged from 25.6 to 59%. Fifteen hymenopterous parasitoid species were recovered from cocoons, of which three species were primary parasitoids, two were obligatory hyperparasitoids and the remaining 10 species were facultative hyperparasitoids. The primary parasitoid, Chelonus kermakiae (Tobias) (Hymenoptera: Braconidae), was the most abundant comprising almost 85% of the total emerging parasitoids. In addition, a further four species of larval parasitoid developed within the PTBM's larval tunnels in pistachio fruit cluster-stem tissue. Conservation of these parasitoids in the pistachio growing areas is recommended since a high level of parasitized moths’ cocoons was found at the majority of experimental sites.     

Development of a biodegradable coating formulation based on the biological characteristics of the Iranian Ultra-filtrated cheese

Type and concentration of edible components, are two main factors which can be affected the chemical, microbial, quality, sensory properties and storage life of coated cheese. In this work, to optimize the concentrations of chitosan and Natamycin for coating Iranian white UF cheese response surface methodology was used. The effects of main edible coating components, chitosan (0.5–2.5%, w/w) and Natamycin (5–20 ppm) on pH, TSS, bacterial total count, yeast and mould population and starter of coated cheese were studied up to 3 weeks after storage at 4?±?2 °C. The obtained results indicated that the second-order polynomial models could be successfully generated with high coefficient of determination (R²?≥?0.9153) using experimental data for all the studied response variables. The optimum concentrations of chitosan and Natamycin were obtained at 1.6% w/w and 18.5 ppm, respectively which the predicted values for pH, TSS, bacterial total count, yeast and mould population and starter were 4.5, 37%, 12 cfu, 14 cfu and 346 cfu, respectively. The verification test was done at obtained optimum concentrations of the main edible components and the statistical analysis indicated insignificant (p?>?0.05) differences between the predicted and experimental values of the response variables.     

Anti-fungal resistance in candida isolated from oral and diaper rash candidiasis in neonates

The purpose of the present study is to evaluate the sensitivity of Candida species isolated from oral candidiasis and diaper dermatitis infections in children. The children referring to private and public clinics in Ilam, Iran were exmined for oral candidiasis and diaper dermatitis. In this study, 248 oral candidiasis and diaper dermatitis samples were collected and cultured.Candida species were identified by using standard methods. Resistance and sensitivity to amphotericin B, nystatin, ketoconazole, fluconazole, itraconazole, clotrimazole, and posaconazole were determined using the CLSI M44-A standard disk diffusion method. From the 248 studied samples, 149 were positive for Candida, among which the Candida albicans was the most prevalent (64.4%). The resistance of different Candida species to nystatin, itraconazole, fluconazole, ketoconazole, clotrimazole, voriconazole, and posaconazole were 4, 43, 34.2, 34.9, 21.5, 6, and 6.7%, respectively. No resistance to amphotericin B was observed. Considering rather low resistance to nystatin, this drug is the best choice for oral candidiasis and diaper dermatitis.     

Design,synthesis and SAR studies of 4-allyoxyaniline amides as potent 15-lipoxygensae inhibitors

A group of 4-allyloxyaniline amides 5a–o were designed, synthesized and evaluated as potential inhibitors of soybean 15-lipoxygenase (SLO) on the basis of eugenol and esteragol structures. Compound 5e showed the best IC₅₀ in SLO inhibition (IC₅₀ = 0.67 ± 0.06 μM). All compounds were docked in SLO active site retrieved from RCSB Protein Data Bank (PDB entry: 1IK3) and showed that allyloxy group of compounds is oriented towards the Fe³⁺-OH moiety in the active site of enzyme and fixed by hydrogen bonding with two conserved His⁵¹³ and Gln⁷¹⁶. It is resulted that molecular volume of the amide moiety would be a major factor in inhibitory potency variation of the synthetic amides, where the hydrogen bonding of the amide group could also involve in the activity of the inhibitors.     

Deep aspirations: towards a sustainable offshore Blue Economy

Reviews in Fish Biology and Fisheries - The ocean economy is experiencing rapid growth that will provide benefits but will also pose environmental and social risks. With limited space and degraded...     

Hepatocyte growth factor protects against hypoxia/reoxygenation-induced apoptosis in endothelial cells

Hypoxia/reoxygenation causes cellular injury and death associated with a number of pathophysiological conditions, including myocardial ischemia/reperfusion injury and stroke. The cell death pathways induced by hypoxia/reoxygenation and their underlying regulatory mechanisms remain poorly understood. Recent studies have shown that hypoxia/reoxygenation can induce Bax translocation and cytochrome c release. Using murine lung endothelial cells as a model, we found that the induction of apoptosis by hypoxia/reoxygenation involved the activation of both Bax-dependent and death receptor-mediated pathways. We demonstrated the activation of the death-inducing signal complex and Bid pathway after hypoxia/reoxygenation. Hepatocyte growth factor markedly inhibited hypoxia/reoxygenation-induced endothelial cell apoptosis. The cytoprotection afforded by hepatocyte growth factor was mediated in part by the stimulation of FLICE-like inhibiting protein expression, the attenuation of death-inducing signal complex formation, and the inhibition of Bid and Bax activation. Hepatocyte growth factor also prevented cell injury and death by increasing the expression of the antiapoptotic Bcl-XL protein. The inhibition of Bid/Bax-induced cell death by hepatocyte growth factor primarily involved p38 MAPK and in part Akt-dependent pathways but not ERK1/ERK2.     

Tunable Plasmonic Absorber Based on TiN-Nanosphere Liquid Crystal Hybrid in Visible and Near-Infrared Regions

In this paper, a tunable plasmonic absorber based on TiN-nanosphere/liquid crystal (LC) nanocomposite in visible and near-infrared regions is proposed. TiN-nanosphere/LC nanocomposite is a combination of titanium nitride (TiN) nanospheres dispersed in a host of LC and plays the main role in post fabrication tunability. The proposed absorber has three more than 90% absorption peaks and the absorption tunability of about 76 nm. It is shown that TiN-nanospheres are able to support localized surface plasmon resonance (LSPR). The Maxwell-Garnett theory is utilized to approximate the permittivity of the composite structure. Also, the effect of geometric parameters on the absorption is studied. Moreover, a single sheet of graphene is utilized to compensate the decrement of the absorption caused by the geometric parameters.     

Analyses of the Redistribution of Work following Cardiac Resynchronisation Therapy in a Patient Specific Model

Regulation of regional work is essential for efficient cardiac function. In patients with heart failure and electrical dysfunction such as left branch bundle block regional work is often depressed in the septum. Following cardiac resynchronisation therapy (CRT) this heterogeneous distribution of work can be rebalanced by altering the pattern of electrical activation. To investigate the changes in regional work in these patients and the mechanisms underpinning the improved function following CRT we have developed a personalised computational model. Simulations of electromechanical cardiac function in the model estimate the regional stress, strain and work pre- and post-CRT. These simulations predict that the increase in observed work performed by the septum following CRT is not due to an increase in the volume of myocardial tissue recruited during contraction but rather that the volume of recruited myocardium remains the same and the average peak work rate per unit volume increases. These increases in the peak average rate of work is is attributed to slower and more effective contraction in the septum, as opposed to a change in active tension. Model results predict that this improved septal work rate following CRT is a result of resistance to septal contraction provided by the LV free wall. This resistance results in septal shortening over a longer period which, in turn, allows the septum to contract while generating higher levels of active tension to produce a higher work rate.