A COMPUTATIONAL APPROACH ON UNDERSTANDING STRUCTURAL INTERACTIONS OF ENVELOPE PROTEIN OF DENGUE VIRUS BOUND WITH SQUALENE, A PROTOTYPE ANTI-VIRAL COMPOUND

Objective: The objective of the work was to validate the structural binding affinity of Squalene with the envelope protein of Dengue virus by means of molecular simulations. Methods: Three-dimensional (3D) structure of dengue 2 virus envelope protein was retrieved from Protein Data Bank PDB and Squalene compound from the ZINC database. Molecular docking between the E protein and Squalene were carried out by means of Auto Dock 4.2. Results: Based on the study, it was observed that the binding/docking energy for the complex structure was calculated to be-5.55 kcal/mol. Critical residues to interact with E protein were scrutinized by analyzing the interface of the complex within 4 Å proximity. Residues such as Thr 48, Glu49, Ala 50, Val 130, Leu 135, Ser 186, Pro 187, Thr 189, Gly 190, Leu 191, Phe 193, Leu 198, Leu 207, Thr 268, Phe 279, Thr 280, Gly 281, His 282 and Leu 283 were found to be non-covalently located around the squalene. Conclusion: Scopes to design de novo anti-viral compounds to the dengue viruses by using squalene as a new class of template structure have also been concisely brought into fore

Residue from vacuum ultraviolet irradiation of benzene ices: Insights into the physical structure of astrophysical dust

We have irradiated benzene ices deposited at 4 K on a cold, interstellar dust analog with vacuum ultraviolet (9 eV) irradiation for periods lasting from several hours to nearly a day, after which the irradiated ice was warmed to room temperature. Vacuum ultraviolet photoabsorption spectra of the aromatic residue left at room temperature were recorded and showed the synthesis of benzene derivatives. The residue was also imaged using an electron microscope and revealed crystals of various sizes and shapes. The result of our experiments suggests such geometrically shaped dust particles may be a key component of interstellar dust

Predictors of mortality among hospitalized COVID-19 patients and risk score formulation for prioritizing tertiary care—An experience from South India

BACKGROUND: We retrospectively data-mined the case records of Reverse Transcription Polymerase Chain Reaction (RT-PCR) confirmed COVID-19 patients hospitalized to a tertiary care centre to derive mortality predictors and formulate a risk score, for prioritizing admission. METHODS AND FINDINGS: Data on clinical manifestations, comorbidities, vital signs, and basic lab investigations collected as part of routine medical management at admission to a COVID-19 tertiary care centre in Chengalpattu, South India between May and November 2020 were retrospectively analysed to ascertain predictors of mortality in the univariate analysis using their relative difference in distribution among ‘survivors’ and ‘non-survivors’. The regression coefficients of those factors remaining significant in the multivariable logistic regression were utilised for risk score formulation and validated in 1000 bootstrap datasets. Among 746 COVID-19 patients hospitalised [487 “survivors” and 259 “non-survivors” (deaths)], there was a slight male predilection [62.5%, (466/746)], with a higher mortality rate observed among 40–70 years age group [59.1%, (441/746)] and highest among diabetic patients with elevated urea levels [65.4% (68/104)]. The adjusted odds ratios of factors [OR (95% CI)] significant in the multivariable logistic regression were SaO(2)3; 3.01 (1.61–5.83), Age ≥50 years;2.52 (1.45–4.43), Pulse Rate ≥100/min: 2.02 (1.19–3.47) and coexisting Diabetes Mellitus; 1.73 (1.02–2.95) with hypertension and gender not retaining their significance. The individual risk scores for SaO(2)3–11, Age ≥50 years-9, Pulse Rate ≥100/min-7 and coexisting diabetes mellitus-6, acronymed collectively as ‘OUR-ARDs score’ showed that the sum of scores ≥ 25 predicted mortality with a sensitivity-90%, specificity-64% and AUC of 0.85. CONCLUSIONS: The ‘OUR ARDs’ risk score, derived from easily assessable factors predicting mortality, offered a tangible solution for prioritizing admission to COVID-19 tertiary care centre, that enhanced patient care but without unduly straining the health system

Semi-Volatile Organic Compounds in Car Dust: A Pilot Study in Jeddah, Saudi Arabia

People may spend a significant amount of their daily time in cars and thus be exposed to chemicals present in car dust. Various chemicals are emitted from during car use, contaminating the car dust. In this study, we compiled published and unpublished data on the occurrence of phthalates, flame retardants (FRs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in Saudi car dust. Phthalates, a class of chemical commonly used as plasticizers in different car parts, were the major pollutants found in car dust, with a median value of ∑phthalates 1,279,000 ng/g. Among other chemicals, organophosphate flame retardants (OPFRs) were found to be between 1500–90,500 ng/g, which indicates their use as alternative FRs in the car industry. The daily exposure to Saudi drivers (regular and taxi drivers) was below the respective reference dose (RfD) values of the individual chemicals. However, the estimated incremental lifetime cancer risk (ILCR) values due to chronic exposure to these chemicals was >1 × 10−5 for taxi drivers for phthalates and PAHs, indicating that the long-term exposure to these chemicals is a cause of concern for drivers who spend considerable time in cars. The study has some limitations, due to the small number of samples, lack of updated RfD values, and missing cancer slope factors for many studied chemicals. Despite these limitations, this study indicates the possible range of exposure to drivers from chemicals in car dust and warrants further extensive studies to confirm these patterns

Recent development on carbon based heterostructures for their applications in energy and environment: A review

Nanostructured carbon based materials with unique and tunable properties make them to be utilized for various applications in different forms especially for energy and environmental applications. Carbon is a distinctive chemical element which has superior properties such as porous structure, low cost, resistance to basic and acidic conditions, easy accessibility, low density, good recycling properties, more abundant and ability to combine with other chemical elements in different ways. In this review, we have critically assessed the recent developments in carbon based heterostructures for their applications in energy and environment. Special consideration has been paid on the applications in dye-sensitized solar cells, hydrogen evolution reaction, oxygen evolution reaction, Li-ion battery, supercapacitor, photocatalysis for the degradation of organic pollutants, electrochemical/bio sensors and biomedical applications. Finally, the challenges and future developments of carbon based heterostructures for applications in energy and environment are also outlined. (C) 2018 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserve

Complex macroscale structures formed by the shock processing of amino acids and nucleobases -- implications to the origins of life

The building blocks of life, amino acids and nucleobases, are believed to have been synthesized in the extreme conditions that prevail in space starting from simple molecules containing hydrogen, carbon, oxygen and nitrogen. However, the fate and role of amino acids and nucleobases when they are subjected to similar processes largely remains unexplored. Here we report, for the first time, that shock processed amino acids and nucleobases tend to form complex macroscale structures. Such structures are formed on timescales of about 2 ms. This discovery suggests that the building blocks of life could have polymerized not just on Earth but on other planetary bodies. Our study also provides further experimental evidence for the 'threads' observed in meteorites being due to assemblages of (bio)molecules arising from impact induced shocks.by Vijay Thiruvenkatam et al

Shock Processing of Amino Acids Leading to Complex Structures—Implications to the Origin of Life

The building blocks of life, amino acids, are believed to have been synthesized in the extreme conditions that prevail in space, starting from simple molecules containing hydrogen, carbon, oxygen and nitrogen. However, the fate and role of amino acids when they are subjected to similar processes largely remain unexplored. Here we report, for the first time, that shock processed amino acids tend to form complex agglomerate structures. Such structures are formed on timescales of about 2 ms due to impact induced shock heating and subsequent cooling. This discovery suggests that the building blocks of life could have self-assembled not just on Earth but on other planetary bodies as a result of impact events. Our study also provides further experimental evidence for the ‘threads’ observed in meteorites being due to assemblages of (bio)molecules arising from impact-induced shocks