A Hydrophobic Network: Intersubunit and Intercapsomer Interactions Stabilizing the Bacteriophage P22 Capsid.

Double-stranded DNA (dsDNA) tailed phages and herpesviruses assemble their capsids using coat proteins that have the ubiquitous HK97 fold. Though this fold is common, we do not have a thorough understanding of the different ways viruses adapt it to maintain stability in various environments. The HK97-fold E-loop, which connects adjacent subunits at the outer periphery of capsomers, has been implicated in capsid stability. Here, we show that in bacteriophage P22, residue W61 at the tip of the E-loop plays a role in stabilizing procapsids and in maturation. We hypothesize that a hydrophobic pocket is formed by residues I366 and W410 in the P domain of a neighboring subunit within a capsomer, into which W61 fits like a peg. In addition, W61 likely bridges to residues A91 and L401 in P-domain loops of an adjacent capsomer, thereby linking the entire capsid together with a network of hydrophobic interactions. There is conservation of this hydrophobic network in the distantly related P22-like phages, indicating that this structural feature is likely important for stabilizing this family of phages. Thus, our data shed light on one of the varied elegant mechanisms used in nature to consistently build stable viral genome containers through subtle adaptation of the HK97 fold.IMPORTANCE Similarities in assembly reactions and coat protein structures of the dsDNA tailed phages and herpesviruses make phages ideal models to understand capsid assembly and identify potential targets for antiviral drug discovery. The coat protein E-loops of these viruses are involved in both intra- and intercapsomer interactions. In phage P22, hydrophobic interactions peg the coat protein subunits together within a capsomer, where the E-loop hydrophobic residue W61 of one subunit packs into a pocket of hydrophobic residues I366 and W410 of the adjacent subunit. W61 also makes hydrophobic interactions with A91 and L401 of a subunit in an adjacent capsomer. We show these intra- and intercapsomer hydrophobic interactions form a network crucial to capsid stability and proper assembly

ORAL DOSAGES FORM: MEDICINE CONTAINING CHEWIMG GUM: A REVIEW

Chewing gums are mobile drug delivery systems. It is a potentially useful means of administering drugs either locally or systemically via, the oral cavity. Several ingredients are now incorporated in medicated chewing gum, e.g. Fluoride for prophylaxis of dental caries, chlorhexidine as local disinfectant, nicotine for smoking cessation, aspirin as an analgesic, and caffeine as a stay alert preparation. It was concluded that chewing gum is an excellent drug delivery system for self-medication as it is convenient and can be administered directly without water and they contain one or more active substances which are released by chewing and are intended to be used for local treatment of mouth diseases or systemic delivery after absorption through the buccal mucosa.Key-words: Medicated Chewing Gum, Mouth Diseases, Oral Drug Delivery System.Â

Effect of slant angle variation on the drag force for Ahmed body car model

In this paper, numerical investigation is carried out on two-dimensional Ahmed body model using Computational Fluid Dynamics in ANSYS Fluent 19.1. The 2-D model is designed in Catia v5 for 25°, 35° and 45° slant angles. The turbulent model used to analyze the flow dynamics is Realizable k-ε model. The drag coefficient variation with respect to slant angle is computed. The skin friction coefficient, wall shear stress and frictional velocity are also calculated

Numerical modelling of shear thickening fluid in nanosilica dispersion

In this paper, a numerical model of the shear thickening fluid (STF) is generated and the rheological properties are compared with the experimental data. Power Law model has been used to fit the rheological data for STF. Experimental data is taken from a performed study and a user defined function (UDF) has been written to develop the shear thickening behavior. The purpose of this study is to exactly model the behavior of shear thickening fluids by using UDF, to explain the shear-thickening mechanisms under different shear rates. Different parameters like viscosity, shear stress and velocity of the STF have also been reported

FORMULATION AND EVALUATION OF MATRIX DIFFUSION CONTROLLED TRANSDERMAL DRUG DELIVERY SYSTEM OF GLIPIZIDE

Abstract: Context: There has been a tremendous increase in interest for transdermal drug delivery system for sustain release dosage form in chronic manageable diseased conditions like diabetes, hypertension etc to reduce the frequency of dosing. It reduces the risk of exposing the body to drug above maximum safe concentration in case of dosage form failure in comparison to oral sustained release drug delivery system. Aims: Transdermal patches of Glipizide were formulated to achieve sustain release pattern within the therapeutic range. Methods and Material: HPMC 5cps, HPMC 15cps, HPMC K-100M, Ethyl cellulose (EC), Eudragit RS 100 (ERS-100) and Polyvinylpyrrolidone (PVP) K30 were used as matrix forming polymer. Propylene glycol was used as penetration enhancer. Polyethylene glycol (PEG) 400 and n-dibultyl phthalate (n-DB) were used as plasticizer. Methanol and chloroform were used as solvents. Patches were prepared by solvent casting method. Results: Patches prepared, from each batch, gave release profile for over 10 hours. Conclusions: Prepared patches from HPMC 5 cps and ethyl cellulose exhibited good characteristics for sustained release action and other parameters evaluated

FUNGAL INFECTIONS ASSOCIATED WITH COVID-19

To study fungal infections such as Mucormycosis, Aspergillosis, Candidiasis, Cryptococcosis associated with Covid-19. A detailed study was done with the information gathered from the articles in specified databases, online sources, and online published materials to have current details of the situation of fungal infections in covid patients. Fungal infections were seen among covid-19 patients mostly due to opportunistic fungal pathogens such as Mucor, Candida, Aspergillus, and Cryptococcus. The reason behind rising opportunistic fungal infections among covid-19 patients may be the immunocompromised host. The most common species responsible for fungal infections in covid-19 were noticed to be of genus Mucor, A. flavus, and A. fumigatus species of genus Aspergillus, C. albicans species of genus Candida, C. neoformans, and C. gattii species of genus Cryptococcus. Patients suffering or recovered from covid-19 are now facing numerous Secondary Infections. The majority of secondary infections associated with covid-19 are Fungal Infections. Mucormycosis, candidiasis, aspergillosis, cryptococcosis as opportunistic infections are seen widely in the covid-19 treated patients. Rapid progression of such fungal infections is required to be controlled by early diagnosis of infection and by identifying the underlying risk parameters. Protocols for disease management will be beneficial too

Vaccination trends and perceptions as students return to campus among San José State University Students, Fall 2021

As repopulation of San Jose State University (SJSU) continues this fall, students expressed opinions and concerns about returning to campus in person. To better understand the nature of any concerns, a survey was conducted among California higher education students, with nearly 5,000 respondents. The survey was conducted between June 2021 and August 2021. This brief summarizes the findings from 1,760 self-identified SJSU students

Polypropylene nano-composites at high strain rate impacts: Characterization, failure modes, and modeling

As a major challenge, development of light-weight fibre reinforced polymer (FRP) composite body armour, characterization of candidate matrix polymers at high strain rate impact is the focus in this research. Polypropylene (PP) and the nano-composites with 1-5% by weight of NC (nanoclay) platelets are the candidates considered. In the characterization phase, high strain rate impact and quasi-static loading tests were performed to figure out the limiting (failure) responses. Comparison between the material systems is, subsequently, made to nominate one matrix configuration. Enhancements of mechanical properties with increase in weight percentage of the nanoparticles are observed at both quasi-static and dynamic loadings. Observations of dispersed imposed failure modes, development of novel model for failure modulus and evaluation of peak strength values are also attempted.Keywords: Nano-composite, Impact behaviour, Analytical modelling, Polypropylene, Failure mode