33 research outputs found
Understanding Thermoelectric Properties from Density Functional Theory
The electronic band structure and transport properties of SrAgFCh (Ch = S, Se, Te) are studiedusing the
first principle density functional theory and solving the Boltzmann transport equationwithin the
constant relaxation time approximation. The complete structural optimisation is carried out to get the
ground state properties of all the compounds. The calculated ground stateproperties agree quite well
with available experiments. The electronic band structures are calculated by means of the full-potential
linear augmented plane wave method, using the Tran-Blahamodified Becke-Johnson potential and the
calculated band gaps are found to be in good agreement with the experiments aswell as with other
theoretical reports. The spin-orbit coupling shows a significant change in lifting the band degeneracy.
Assuming constant relaxation time approximation, the transport coefficients related to thermoelectric
effect are calculated by solving Boltzmann equation as implemented in BoltzTraP code. The calculated
thermoelectric properties such as thermopower andelectrical conductivity as functions of hole and
electron concentrations shows these compoundsto be promising candidate for better thermoelectric
applications. The thermopower is found todecrease as we move from S to Te, whereas the electrical
conductivity is found to be increaseand we also found that the investigated compounds are good
candidate for p-type doping along the a-axis direction.
Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches
Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly
In silico targeting of lipoxygenase, CYP2C9, and NAD(P)H oxidase by major green tea polyphenols to subvert oxidative stress
Oxidative stress (OS) is a phenomenon caused by an imbalance between free-radical production and antioxidant activity within the body. Status of endogenous antioxidants is not always sufficient to mitigate the oxidative damage. In this case, exogenous antioxidants could help to minimize free-radical production and subsequent OS. Green tea is rich in several phenolic compounds that have strong antioxidant properties. However, their mechanism of action is still unclear. Hence, the present study aims to investigate binding affinities of six green tea polyphenols such as catechin, epicatechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, and gallocatechin for common ROS producers such as Lipoxygenase (LOX), CYP2C9, and NAD(P)H oxidase (NOX). Results indicated that polyphenols interacted with binding pockets of these enzymes through hydrogen bonds and other stable interactions such as van der waals, Pi-Pi, Pi-alkyl, and alkyl. All polyphenols showed varied binding affinities. Among them, epigallocatechin gallate and epigallocatechin showed the highest binding affinities for the ROS producers. Findings of the present study suggest that, apart from free radical scavenging activity, green tea polyphenols may directly interact with binding pockets of LOX, CYP2C9, and NOX to dampen ROS production and OS. However, studies involving animal models are required for additional validation of results
In silico study reveals binding potential of rotenone at multiple sites of pulmonary surfactant proteins : a matter of concern
Rotenone is a broad-spectrum pesticide employed in various agricultural practices all over the world. Human beings are exposed to this chemical through oral, nasal, and dermal routes. Inhalation of rotenone exposes biomolecular components of lungs to this chemical. Biophysical activity of lungs is precisely regulated by pulmonary surfactant to facilitate gaseous exchange. Surfactant proteins (SPs) are the fundamental components of pulmonary surfactant. SPs like SP-A and SP-D have antimicrobial activities providing a crucial first line of defense against infections in lungs whereas SP-B and SP-C are mainly involved in respiratory cycle and reduction of surface tension at air-water interface. In this study, molecular docking analysis using AutoDock Vina has been conducted to investigate binding potential of rotenone with the four SPs. Results indicate that, rotenone can bind with carbohydrate recognition domain (CRD) of SP-A, N-, and C-terminal peptide of SP-B, SP-C, and CRD of SP-D at multiples sites via several interaction mediators such as H bonds, C-H bonds, alkyl bonds, pi-pi stacked, Van der Waals interaction, and other. Such interactions of rotenone with SPs can disrupt biophysical and anti-microbial functions of SPs in lungs that may invite respiratory ailments and pathogenic infections