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1.
Metabolomics ; 20(3): 55, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762651

RESUMEN

INTRODUCTION: The world is experiencing exponential growth in communication, especially wireless communication. Wireless connectivity has recently become a part of everyone's daily life. Recent developments in low-cost, low-power, and miniature devices contribute to a significant rise in radiofrequency-electromagnetic field (RF-EM) radiation exposure in our environment, raising concern over its effect on biological systems. The inconsistent and conflicting research results make it difficult to draw definite conclusions about how RF-EM radiation affects living things. OBJECTIVES: This study identified two micro-environments based on their level of exposure to cellular RF-EM radiation, one with significantly less exposure and another with very high exposure to RF-EM radiation. Emphasis is given to studying the metabolites in the urine samples of humans naturally exposed to these two different microenvironments to understand short-term metabolic dysregulations. METHODS: Untargeted 1H NMR spectroscopy was employed for metabolomics analyses to identify dysregulated metabolites. A total of 60 subjects were recruited with 5 ml urine samples each. These subjects were divided into two groups: one highly exposed to RF-EM (n = 30) and the other consisting of low-exposure populations (n = 30). RESULTS: The study found that the twenty-nine metabolites were dysregulated. Among them, 19 were downregulated, and 10 were upregulated. In particular, Glyoxylate and dicarboxylate and the TCA cycle metabolism pathway have been perturbed. The dysregulated metabolites were validated using the ROC curve analysis. CONCLUSION: Untargeted urine metabolomics was conducted to identify dysregulated metabolites linked to RF-EM radiation exposure. Preliminary findings suggest a connection between oxidative stress and gut microbiota imbalance. However, further research is needed to validate these biomarkers and understand the effects of RF-EM radiation on human health. Further research is needed with a diverse population.


Asunto(s)
Metaboloma , Metabolómica , Ondas de Radio , Humanos , Masculino , Adulto , Metabolómica/métodos , Femenino , Ondas de Radio/efectos adversos , Metaboloma/efectos de la radiación , Persona de Mediana Edad , Campos Electromagnéticos/efectos adversos , Adulto Joven
2.
Langmuir ; 40(28): 14311-14320, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38958522

RESUMEN

Amino acids make up a promising family of molecules capable of direct air capture (DAC) of CO2 from the atmosphere. Under alkaline conditions, CO2 reacts with the anionic form of an amino acid to produce carbamates and deactivated zwitterionic amino acids. The presence of the various species of amino acids and reactive intermediates can have a significant effect on DAC chemistry, the role of which is poorly understood. In this study, all-atom molecular dynamics (MD) based computational simulations and vibrational sum frequency generation (vSFG) spectroscopy studies were conducted to understand the role of competitive interactions at the air-aqueous interface in the context of DAC. We find that the presence of potassium bicarbonate ions, in combination with the anionic and zwitterionic forms of amino acids, induces concentration and charge gradients at the interface, generating a layered molecular arrangement that changes under pre- and post-DAC conditions. In parallel, an enhancement in the surface activity of both anionic and zwitterionic forms of amino acids is observed, which is attributed to enhanced interfacial stability and favorable intermolecular interactions between the adsorbed amino acids in their anionic and zwitterionic forms. The collective influence of these competitive interactions, along with the resulting interfacial heterogeneity, may in turn affect subsequent capture reactions and associated rates. These effects underscore the need to consider dynamic changes in interfacial chemical makeup to enhance DAC efficiency and to develop successful negative emission and storage technologies.

3.
Phys Chem Chem Phys ; 26(31): 20799-20806, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38958742

RESUMEN

The physicochemical phenomena at the solid/electrolyte interfaces govern various industrial processes ranging from energy generation, storage, and catalysis to chemical separations and purification. Adsorption-based solid/liquid extraction methods are promising for the selective and rapid separation of nuclear (such as uranium) and other critical materials. In this study, we quantified the adsorption, complexation, and dynamics of UO22+ ions on the graphene surface in various electrolyte media (LiNO3, NaNO3 and CsNO3) using all-atom molecular dynamics simulations, in combination with network theory based subensemble analysis, enhanced sampling, and temporal analysis. We observe that the choice of background electrolyte impacts the propensity of UO22+ adsorption on the graphene surface, with LiNO3 being the most favorable at both low and high uranyl-nitrate concentrations. Even though UO22+ primarily retained its coordination with water and interacted via the outer-sphere mechanism with graphene, the interfacial segregation of NO3- increased the number of contact ion pairs (CIPs) between UO22+ and NO3- ions, and the residence times of UO22+ within the interfacial region. This study provides a fundamental understanding of the structure and dynamics of UO22+ on the solid surface necessary to design advanced adsorption-based separation methods for energy-relevant materials.

4.
Phys Chem Chem Phys ; 26(4): 3152-3158, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38189478

RESUMEN

Ion recognition in porous aqueous media utilizing polyethers involves the formation of 1 : 1 and higher-order host-guest complexes. The effectiveness of these interactions relies on the optimal size of the host cavity to encapsulate the guest ions. While liquid/liquid extraction based on host-guest interactions offers higher specificity in metal ion extraction, it results in the co-extraction of unwanted coordinating solvents and counter-anions. Therefore, an improved protocol is required by which the ion can be selectively trapped within the host cavity and simultaneously decrease the guest coordination with the outside environment. This study delves into the microscopic mechanisms underpinning the exclusive ion recognition through the formation of 2 : 1 host-guest sandwich complexes, which reduce metal coordination with solvent or counter-ions, ensuring selectivity. Our analysis shows that ions with a radius larger than the host cavity, such as cesium (Cs+), form stable host-guest sandwich complexes at elevated host concentrations. In this study, we performed molecular dynamics simulations to investigate the microscopic details of Cs+ interactions with open-chain and preorganized polyethers, namely podand, crown, and cryptand in electrolyte media. Our findings reveal that the formation of stable Cs+-crown sandwich complexes significantly reduces Cs+ coordination with H2O and NO3-. This loss of solute coordination leads to exclusivity in bound metal ions, offering a potential strategy for efficient solvent extraction.

5.
J Chem Phys ; 161(16)2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39450735

RESUMEN

The direct air capture (DAC) of CO2 using aqueous solvents is plagued by slow kinetics and interfacial barriers that limit effectiveness in combating climate change. Functionalizing air/aqueous surfaces with charged amphiphiles shows promise in accelerating DAC; however, insight into these interfaces and how they evolve in time remains poorly understood. Specifically, competitive ion interactions between DAC reagents and reaction products feedback onto the interfacial structure, thereby modulating interfacial chemical composition and overall function. In this work, we probe the role of glycine amino acid anions (Gly-), an effective CO2 capture reagent, that promotes the organization of cationic oligomers at air/aqueous interfaces. These surfaces are probed with vibrational sum frequency generation spectroscopy and molecular dynamics simulations. Our findings demonstrate that the competition for surface sites between Gly- and captured carbonaceous anions (HCO3-, CO32-, carbamates) drives changes in surface hydration, which in turn tunes oligomer ordering. This phenomenon is related to a hierarchical ordering of anions at the surface that are electrostatically attracted to the surface and their ability to compete for interfacial water. These results point to new ways to tune interfaces for DAC via stratification of ions based on relative surface propensities and specific ion effects.

6.
Homeopathy ; 113(4): 211-222, 2024 11.
Artículo en Inglés | MEDLINE | ID: mdl-38714214

RESUMEN

BACKGROUND: Prior vaccination is often studied for its impact on individuals' post-infection prognosis. Ayurveda, Yoga, Unani, Siddha and Homeopathy (AYUSH) medicines, advised by the Government of India as prophylaxis during the first wave of the coronavirus disease 2019 (COVID-19) pandemic, were consumed by the masses in 2020. A study was therefore undertaken to observe any association between the prior usage of AYUSH prophylactic medicines and post-infection severity as reported by recovered COVID-19 individuals. METHODS: This was a retrospective, multi-centre, cohort study conducted in 21 cities of India from 5th August to 30th November 2020. Data from recovered COVID-19 patients, of either sex or any age, captured information about AYUSH prophylactic medicines intake prior to infection, disease severity, symptomatology, duration of complaints, etc. The study participants were grouped into AYUSH intake and non-intake. Primary composite outcome was the disease clinical course. Secondary clinical outcomes were the rate of and time to clinical recovery. RESULTS: Data of 5,023 persons were analysed. Ayurveda or homeopathic prophylactic medicines were consumed by more than half of the study participants: that is, 56.85% (n = 1,556) and 56.81% (n = 1,555) respectively. The overall adjusted protective effect (PE) of AYUSH prophylactic intake against moderate/severe forms of COVID-19 disease was 56.7% (95% confidence interval [CI], 48.7 to 63.50; p < 0.001). Adjusted PE for homeopathy and Siddha was 52.9% (95% CI, 42.30 to 61.50; p < 0.001) and 59.8% (95% CI, 37.80 to 74.10; p < 0.001), respectively. A statistically significant association was found between AYUSH prophylactic medicine intake and clinical recovery more frequently by the 3rd day of illness (χ2 = 9.01; p = 0.002). Time to resolution of symptoms in the AYUSH intake group was on average 0.3 days earlier than in the non-intake group (p = 0.002). CONCLUSION: AYUSH prophylactics were associated with statistically significant levels of protection against COVID-19 disease severity. Amongst these, previous intake of homeopathy or Siddha medicines was associated with some protection against moderate/severe illness and with a somewhat quicker clinical recovery. Prospective studies with experimental research design are needed to validate the findings of this study. STUDY REGISTRATION: Clinical Trials Registry-India (CTRI/2020/08/027000).


Asunto(s)
COVID-19 , Homeopatía , Medicina Ayurvédica , Índice de Severidad de la Enfermedad , Humanos , Estudios Retrospectivos , Femenino , Masculino , COVID-19/prevención & control , India , Adulto , Persona de Mediana Edad , Homeopatía/estadística & datos numéricos , Homeopatía/métodos , SARS-CoV-2 , Estudios de Cohortes , Anciano , Adulto Joven , Adolescente , Tratamiento Farmacológico de COVID-19
7.
Toxicol Mech Methods ; 34(2): 214-235, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37921264

RESUMEN

Fluorosis, a chronic condition brought on by excessive fluoride ingestion which, has drawn much scientific attention and public health concern. It is a complex and multifaceted issue that affects millions of people worldwide. Despite decades of scientific research elucidating the causes, mechanisms, and prevention strategies for fluorosis, there remains a significant gap between scientific understanding and public health implementation. While the scientific community has made significant strides in understanding the etiology and prevention of fluorosis, effectively translating this knowledge into public health policies and practices remains challenging. This review explores the gap between scientific research on fluorosis and its practical implementation in public health initiatives. It suggests developing evidence-based guidelines for fluoride exposure and recommends comprehensive educational campaigns targeting the public and healthcare providers. Furthermore, it emphasizes the need for further research to fill the existing knowledge gaps and promote evidence-based decision-making. By fostering collaboration, communication, and evidence-based practices, policymakers, healthcare professionals, and the public can work together to implement preventive measures and mitigate the burden of fluorosis on affected communities. This review highlighted several vital strategies to bridge the gap between science and public health in the context of fluorosis. It emphasizes the importance of translating scientific evidence into actionable guidelines, raising public awareness about fluoride consumption, and promoting preventive measures at individual and community levels.


Asunto(s)
Fluoruros , Fluorosis Dental , Humanos , Fluoruros/toxicidad , Fluorosis Dental/epidemiología , Fluorosis Dental/etiología , Fluorosis Dental/prevención & control , Salud Pública , Fluoruración/efectos adversos
8.
J Am Chem Soc ; 145(26): 14387-14394, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37343135

RESUMEN

Described in this work are calix[4]pyrrole-based ion-pair receptors, cis/trans-1 and cis/trans-2, designed for the extraction of sodium hydroxide. An X-ray diffraction analysis of a single crystal of the cis-1·NaOH isomer isolated from a mixture of cis/trans-1 revealed a unique dimeric supramolecular structure. An average dimer in toluene-d8 solution was inferred on the basis of diffusion-ordered spectroscopy (DOSY). Support for the proposed stoichiometry came from density functional theory (DFT) calculations. The structural stability of the dimeric cis-1·NaOH complex in toluene solution was further confirmed by ab initio molecular dynamics (AIMD) simulation with explicit representation of solvent. Under conditions of liquid-liquid extraction (LLE), purified receptors cis- and trans-2 were both found to remove NaOH from a pH 11.01 aqueous source phase into toluene with extraction efficiencies (E%) of 50-60% when used equimolar to NaOH. However, in all cases, precipitation was observed. Complexities associated with precipitation could be avoided by immobilization of the receptors onto a chemically inert poly(styrene) resin by means of solvent impregnation. The use of solvent-impregnated resins (SIRs) eliminated precipitation in solution while retaining the extraction efficiency toward NaOH. This allowed both the pH and salinity of the alkaline source phase to be lowered.

9.
J Am Chem Soc ; 145(8): 4527-4533, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36789888

RESUMEN

Electrons in solids often adopt complex patterns of chemical bonding driven by the competition between energy gains from covalency and delocalization, and energy costs of double occupation to satisfy Pauli exclusion, with multiple intermediate states in the transition between highly localized, and magnetic, and delocalized, and nonmagnetic limits. Herein, we report a chemical pressure-driven transition from a proper Mn magnetic ordering phase transition to a Mn magnetic phase crossover in EuMn2P2 the limiting end member of the EuMn2X2 (X = Sb, As, P) family of layered materials. This loss of a magnetic ordering occurs despite EuMn2P2 remaining an insulator at all temperatures, and with a phase transition to long-range Eu antiferromagnetic order at TN ≈ 17 K. The absence of a Mn magnetic phase transition contrasts with the formation of long-range Mn order at T ≈ 130 K in isoelectronic EuMn2Sb2 and EuMn2As2. Temperature-dependent specific heat and 31P NMR measurements provide evidence for the development of short-range Mn magnetic correlations from T ≈ 250-100 K, interpreted as a precursor to covalent bond formation. Density functional theory calculations demonstrate an unusual sensitivity of the band structure to the details of the imposed Mn and Eu magnetic order, with an antiferromagnetic Mn arrangement required to recapitulate an insulating state. Our results imply a picture in which long-range Mn magnetic order is suppressed by chemical pressure, but that antiferromagnetic correlations persist, narrowing bands and producing an insulating state.

10.
Chemphyschem ; 24(9): e202200808, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36683491

RESUMEN

An inexpensive computational method is designed to demonstrate the efficacy of the complex COF toward CO2 capture. The interaction energy calculations of small repeating units of COF precisely demonstrate CO2 uptake capacity at high pressure and effective dual descriptors values of these repeating units of COFs accurately establish their structure-property relationships under ambient conditions. The computational findings are in consonance with experimental results reported by Yaghi and coworkers. Further, the computationally modelled COFs confirms that the addition of -NH2 increases the effective dual descriptors values of COFs. Whereas an increase in the size of a central aromatic unit of COF6 shows better interactions. Interaction energy and effective dual descriptor calculations demonstrate the CO2 capture abilities of COFs at high pressure and low pressure respectively. The method developed by our group would be useful in high throughput designing and screening of a large number of complex COFs at different pressure.

11.
Chem Rev ; 121(5): 2780-2815, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33151662

RESUMEN

Topology, a mathematical concept, has recently become a popular and truly transdisciplinary topic encompassing condensed matter physics, solid state chemistry, and materials science. Since there is a direct connection between real space, namely atoms, valence electrons, bonds, and orbitals, and reciprocal space, namely bands and Fermi surfaces, via symmetry and topology, classifying topological materials within a single-particle picture is possible. Currently, most materials are classified as trivial insulators, semimetals, and metals or as topological insulators, Dirac and Weyl nodal-line semimetals, and topological metals. The key ingredients for topology are certain symmetries, the inert pair effect of the outer electrons leading to inversion of the conduction and valence bands, and spin-orbit coupling. This review presents the topological concepts related to solids from the viewpoint of a solid-state chemist, summarizes techniques for growing single crystals, and describes basic physical property measurement techniques to characterize topological materials beyond their structure and provide examples of such materials. Finally, a brief outlook on the impact of topology in other areas of chemistry is provided at the end of the article.

12.
Environ Res ; 218: 115021, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36495961

RESUMEN

Numerous solution-based methods are used to prepare zinc oxide (ZnO) and graphene oxide (GO) nanocomposite (ZnO-GO NCs) such as sol-gel, hydrothermal, and precipitation. These methods require lots of reagents and involve many stages. In this study, a novel one-step solution-based discharge method is used to prepare ZnO-GO NCs through an electrochemical discharge process (ECDP) without the use of any catalyst or toxic chemical reagent. This study focused on analyzing the effects of input parameters on the production rate of ZnO-GO NCs. The experiment was performed by using Taguchi L9 orthogonal array. Materials removal rate (MRR) is considered as output response. The results reveal that voltage is the most significant factor, followed by temperature and duty cycle for obtaining higher MRR. The optimum parameters obtained from the Minitab software for higher MRR are 40 V, 30%, and 45 °C. Further, the morphology of the nanoparticles (NCs) produced at optimum parameters is analyzed which shows flower shape NCs with multilayer graphene oxide, confirmed by the FESEM and TEM images. The XRD peak at 11.27° and Raman spectroscopy peak of G and D bands reveal GO formation. The prepared ZnO-GO NCs tested as supercapacitor activity in the KOH solution. At the optimum parameter, the specific capacitance is observed to be 523.4 F/g at 2A/g current density. The NCs electrode shows good cyclic stability, with 86% retention of specific capacitance after 5000 cycles. This study shows a promising future of converting the e-waste product into valuable nanomaterials such as GO and ZnO from used dry cell batteries.


Asunto(s)
Grafito , Nanocompuestos , Óxido de Zinc , Óxido de Zinc/química , Nanocompuestos/química , Grafito/química , Flores
13.
J Org Chem ; 87(19): 12547-12557, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-35584056

RESUMEN

A thorough DFT study was performed to unravel the true mechanism involved in the Pd(0)-catalyzed functional group transposition between aroyl chlorides and aryl iodides. Two different experimental groups proposed different mechanisms for the functional group transposition reaction. A careful assessment of experimental findings and thorough computational studies endorsed that the functional group transposition proceeds via phosphonium salt formation and ligand-enabled C-P bond metathesis, leading to the formation of the PhI and the intermediate 2. After the formation of the intermediate 2, the transposition of functional groups takes place through the interpalladium ligand exchange mechanism, where two palladium centers act as shuttle catalysts. In short, both C-P bond metathesis and interpalladium ligand exchange steps are crucial in the functional group transposition mechanism.

14.
Monaldi Arch Chest Dis ; 92(4)2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35315260

RESUMEN

COVID-19 vaccine hesitancy among chronic disease patients can severely impact individual health with the potential to impede mass vaccination essential for containing the pandemic. The present study was done to assess the COVID-19 vaccine antecedents and its predictors among chronic disease patients. This cross-sectional study was conducted among chronic disease patients availing care from a primary health facility in urban Jodhpur, Rajasthan. Factor and reliability analysis was done for the vaccine hesitancy scale to validate the 5 C scale. Predictors assessed for vaccine hesitancy were modelled with help of machine learning (ML). Out of 520 patients, the majority of participants were female (54.81%). Exploratory factor analysis revealed four psychological antecedents' "calculation"; "confidence"; "constraint" and "collective responsibility" determining 72.9% of the cumulative variance of vaccine hesitancy scale. The trained ML algorithm yielded an R2 of 0.33. Higher scores for COVID-19 health literacy and preventive behaviour, along with family support, monthly income, past COVID-19 screening, adherence to medications and age were associated with lower vaccine hesitancy. Behaviour changes communication strategies targeting COVID-19 health literacy and preventive behaviour especially among population sub-groups with poor family support, low income, higher age groups and low adherence to medicines may prove instrumental in this regard.


Asunto(s)
COVID-19 , Vacunación , Humanos , Femenino , Masculino , Estudios Transversales , Vacunación/psicología , Aceptación de la Atención de Salud , Conocimientos, Actitudes y Práctica en Salud , Vacunas contra la COVID-19/uso terapéutico , COVID-19/epidemiología , COVID-19/prevención & control , Reproducibilidad de los Resultados , Vacilación a la Vacunación , India/epidemiología , Enfermedad Crónica , Aprendizaje Automático
15.
Indian J Crit Care Med ; 26(7): 786-790, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36864879

RESUMEN

Introduction: Cardiac troponin-I (cTnI) elevation release during hypertensive emergencies (HEs) is a frequent epiphenomenon that may tangle management of individuals being treated for HEs. The primary objective of this study was to determine the prevalence, determinants, and clinical significance of cTnI elevation and secondary objective was to find out the prognostic significance of cTnI elevation in patients admitted for HE in the emergency department (ED) of a tertiary care hospital. Methodology: The investigator has employed the quantitative research approach with a prospective observational descriptive design. The population of this study comprised of 205 adults, which included both males and females, who were more than or 18 years of age. The subjects were selected by non-probability purposive sampling technique. The study was conducted from August 2015 to December 2016 (16 months). Ethical permission was obtained from the Institutional Ethics Committee (IEC), Max Super Speciality Hospital, Saket, New Delhi and well-informed written consents were taken from the subjects. The analysis of data was done with the help of SPSS, version 17.0. Results: Out of 205 patients in the study, cTnI elevation was found in 102 patients (49.8%). Moreover, there was increased duration of stay in the hospital in patient with elevated cTnI level with mean duration stay 1.55 ± 0.82 (p <0.001). In addition, cTnI elevation was associated with increased mortality, 11 out of 102 in an elevated cTnI group (10.8%) with p <0.002. Conclusion: It was found that cTnI elevation in individuals affected by various clinical factors. The authors highlighted a high frequency of mortality among the individuals presented with HE with elevated cTnI level, whereas the presence of cTnI was associated with greater odds of death. How to cite this article: Gupta K, Kiran M, Chhabra S, Mehta M, Kumar N. Prevalence, Determinants and Clinical Significance of Cardiac Troponin-I Elevation among Individuals with Hypertensive Emergency: A Prospective Observational Study. Indian J Crit Care Med 2022;26(7):786-790.

16.
Pharmacol Res ; 167: 105484, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33771699

RESUMEN

Recently non-alcoholic fatty liver disease (NAFLD) has grabbed considerable scientific attention, owing to its rapid increase in prevalence worldwide and growing burden on end-stage liver diseases. Metabolic syndrome including obesity, diabetes, and hypertension poses a grave risk to NAFLD etiology and progression. With no drugs available, the mainstay of NAFLD management remains lifestyle changes with exercise and dietary modifications. Nonselective drugs such as metformin, thiazolidinediones (TZDs), ursodeoxycholic acid (UDCA), silymarin, etc., are also being used to target the interrelated pathways for treating NAFLD. Considering the enormous disease burden and the unmet need for drugs, fresh insights into pathogenesis and drug discovery are required. The emergence of the field of epigenetics offers a convincing explanation for the basis of lifestyle, environmental, and other risk factors to influence NAFLD pathogenesis. Therefore, understanding these epigenetic modifications to target the primary cause of the disease might prove a rational strategy to prevent the disease and develop novel therapeutic interventions. Apart from describing the role of epigenetics in the pathogenesis of NAFLD as in other reviews, this review additionally provides an elaborate discussion on exploiting the high plasticity of epigenetic modifications in response to environmental cues, for developing novel therapeutics for NAFLD. Besides, this extensive review provides evidence for epigenetic mechanisms utilized by several potential drugs for NAFLD.


Asunto(s)
Epigénesis Genética , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/terapia , Animales , Manejo de la Enfermedad , Descubrimiento de Drogas , Epigénesis Genética/efectos de los fármacos , Estilo de Vida Saludable , Humanos
17.
Proc Natl Acad Sci U S A ; 115(37): 9140-9144, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-30154165

RESUMEN

Topological materials ranging from topological insulators to Weyl and Dirac semimetals form one of the most exciting current fields in condensed-matter research. Many half-Heusler compounds, RPtBi (R = rare earth), have been theoretically predicted to be topological semimetals. Among various topological attributes envisaged in RPtBi, topological surface states, chiral anomaly, and planar Hall effect have been observed experimentally. Here, we report an unusual intrinsic anomalous Hall effect (AHE) in the antiferromagnetic Heusler Weyl semimetal compounds GdPtBi and NdPtBi that is observed over a wide temperature range. In particular, GdPtBi exhibits an anomalous Hall conductivity of up to 60 Ω-1⋅cm-1 and an anomalous Hall angle as large as 23%. Muon spin-resonance (µSR) studies of GdPtBi indicate a sharp antiferromagnetic transition (TN) at 9 K without any noticeable magnetic correlations above TN Our studies indicate that Weyl points in these half-Heuslers are induced by a magnetic field via exchange splitting of the electronic bands at or near the Fermi energy, which is the source of the chiral anomaly and the AHE.

18.
Andrologia ; 52(10): e13737, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32613640

RESUMEN

Considering dopamine-enhancing effect of (+)-catechin, the present study was designed to evaluate dopamine-2 (D2) receptor agonistic and phosphodiesterase-5 (PDE5) enzyme inhibitory effects in in silico and effect on male sexual function of Sprague Dawley rats in vivo. (+)-Catechin and standard (sildenafil and bromocriptine) were docked using Autodock Vina 1.1.2 and visualised by UCSF Chimera 1.14. Significant interactions in terms of binding energies were observed for catechin with both proteins. In in vivo study, the rats were dosed orally for 54 days with (+)-catechin hydrate (50 mg/kg), sildenafil citrate (standard, 4 mg/kg) and carboxymethylcellulose (vehicle, 0.25% w/v). The aphrodisiac effects were evaluated on the day 14, 28, 42 and 54 using the behavioural parameters of mounting and intromission. After the study, animals were sacrificed and testes and spermatozoa were assessed for safety profile. Results showed a significant increase in mount and intromission frequencies and a significant reduction in mount and intromission latencies in the catechin group on all tested days when compared to vehicle control. (+)-Catechin was found to be safe on histology of testes, sperm count, sperm motility and sperm morphology parameters. In conclusion, catechin demonstrated an enhancement in sexual behaviour without eliciting toxicity on the male reproductive system in rats.


Asunto(s)
Catequina , Motilidad Espermática , Animales , Catequina/toxicidad , Simulación por Computador , Humanos , Masculino , Extractos Vegetales , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Conducta Sexual Animal
19.
J Cell Physiol ; 234(10): 16703-16723, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30912142

RESUMEN

Chronic obstructive pulmonary disease accounts as the leading cause of mortality worldwide prominently affected by genetic and environmental factors. The disease is characterized by persistent coughing, breathlessness airways inflammation followed by a decrease in forced expiratory volume1 and exacerbations, which affect the quality of life. Determination of genetic, epigenetic, and oxidant biomarkers to evaluate the progression of disease has proved complicated and challenging. Approaches including exome sequencing, genome-wide association studies, linkage studies, and inheritance and segregation studies played a crucial role in the identification of genes, their pathways and variation in genes. This review highlights multiple approaches for biomarker and gene identification, which can be used for differential diagnosis along with the genome editing tools to study genes associated with the development of disease and models their function. Further, we have discussed the approaches to rectify the abnormal gene functioning of respiratory tissues and various novel gene editing techniques like Zinc finger nucleases (ZFN), transcription activator-like effector nucleases (TALEN), and clustered regulatory interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9).


Asunto(s)
Terapia Genética , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/terapia , Biomarcadores , Edición Génica , Humanos
20.
Angew Chem Int Ed Engl ; 58(37): 13107-13112, 2019 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-31342613

RESUMEN

Conductivity, carrier mobility, and a suitable Gibbs free energy are important criteria that determine the performance of catalysts for a hydrogen evolution reaction (HER). However, it is a challenge to combine these factors into a single compound. Herein, we discover a superior electrocatalyst for a HER in the recently identified Dirac nodal arc semimetal PtSn4 . The determined turnover frequency (TOF) for each active site of PtSn4 is 1.54 H2 s-1 at 100 mV. This sets a benchmark for HER catalysis on Pt-based noble metals and earth-abundant metal catalysts. We make use of the robust surface states of PtSn4 as their electrons can be transferred to the adsorbed hydrogen atoms in the catalytic process more efficiently. In addition, PtSn4 displays excellent chemical and electrochemical stabilities after long-term exposure in air and long-time HER stability tests.

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