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1.
Phys Chem Chem Phys ; 26(11): 8794-8806, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38420855

RESUMEN

The emergence of new variants of the novel coronavirus SARS-CoV-2 with increased infectivity, superior virulence, high transmissibility, and unmatched immune escape has demonstrated the adaptability and evolutionary fitness of the virus. The subject of relative order of the binding affinity of SARS-CoV-2 variants with the human ACE2 (hACE2) receptor is hotly debated and its resolution has implications for drug design and development. In this work, we have investigated the energetics of the binding of receptor binding domain (RBD) of SARS-CoV-2 variants of concern (VOCs): Beta (B.1.351), Delta (B.1.617.2), Omicron (B.1.1.529), variant of interest (VOI): Kappa (B.1.617.1), and Delta Plus (B.1.617.2.1) variant with the human ACE2 receptor by using the umbrella sampling (US) method. Our work indicates that Delta and Delta Plus variants have greater values of the US binding free energy than Wild-type (WT), whereas Beta, Kappa, and Omicron variants have lower values. Further analysis of hydrogen bonding, salt bridges, non-bonded interaction energy, and contact surface area at the RBD-hACE2 interface establish Delta as the variant with the highest binding affinity among these variants.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Enzima Convertidora de Angiotensina 2 , Diseño de Fármacos , Unión Proteica , Mutación
2.
Environ Res ; 226: 115669, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36921789

RESUMEN

According to a recent survey, Nepal's urban air quality has been classified as one of the worst in the globe. A large portion of the country's population is subjected to health risks caused by air pollution. As Nepal has a wide variation in altitude coupled with socio-cultural and biological diversities, it is important to understand the different health hazards in the different geographical regions - Terai, Hills and Mountains. Constantly increasing physical infrastructures (such as transport vehicles, open burning of plastics and other fuels) are the main reasons for the escalating air pollution in the country. This study aims to critically review the current air pollution status in different geographical locations along with its impacts on public health in the country. It has been revealed that irrespective of geographic location, the air pollutants interfere with different human physiological systems related to respiration as well as cardiovascular, ophthalmic, and gastrointestinal functioning. Further, the research findings highlighting the influence of prolonged exposure of the population to the air pollution leading to the significant number of deaths have been presented. A notable rise in the number of hospitalized patients suffering from illnesses related to above mentioned pollution borne cases has been reported.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Nepal/epidemiología , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Salud Pública , Biodiversidad , Material Particulado/análisis
3.
Environ Res ; 231(Pt 2): 116148, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37211181

RESUMEN

Platinum nanoparticles (Pt NPs) have numerous applications in various sectors, including pharmacology, nanomedicine, cancer therapy, radiotherapy, biotechnology and environment mitigation like removal of toxic metals from wastewater, photocatalytic degradation of toxic compounds, adsorption, and water splitting. The multifaceted applications of Pt NPs because of their ultra-fine structures, large surface area, tuned porosity, coordination-binding, and excellent physiochemical properties. The various types of nanohybrids (NHs) of Pt NPs can be fabricated by doping with different metal/metal oxide/polymer-based materials. There are several methods to synthesize platinum-based NHs, but biological processes are admirable because of green, economical, sustainable, and non-toxic. Due to the robust physicochemical and biological characteristics of platinum NPs, they are widely employed as nanocatalyst, antioxidant, antipathogenic, and anticancer agents. Indeed, Pt-based NHs are the subject of keen interest and substantial research area for biomedical and clinical applications. Hence, this review systematically studies antimicrobial, biological, and environmental applications of platinum and platinum-based NHs, predominantly for treating cancer and photo-thermal therapy. Applications of Pt NPs in nanomedicine and nano-diagnosis are also highlighted. Pt NPs-related nanotoxicity and the potential and opportunity for future nano-therapeutics based on Pt NPs are also discussed.


Asunto(s)
Antiinfecciosos , Antineoplásicos , Nanopartículas del Metal , Neoplasias , Humanos , Platino (Metal)/química , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química , Óxidos/química , Neoplasias/tratamiento farmacológico
4.
Int J Mol Sci ; 21(14)2020 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-32664524

RESUMEN

Here we report the comprehensive characterization of the secondary metabolites from the leaves of Colebrookea oppositifolia Smith, a species used as medicinal plant in the traditional medicine of Nepal. Phytochemical screening of bioactives was performed using an integrated LC-MSn and high resolution MS (Mass Spectrometry) approach. Forty-three compounds were tentatively identified, mainly aglyconic and glycosilated flavonoids and phenolic acids, as well as other bioactives such as coumarins and terpenes were detected. Furthermore, the NF-κB and AP-1 inhibitory activity of C. oppositifolia extract were evaluated, as well as its cytotoxicity against THP-1 cells, in order to assess the potential use of this herb as a source of anti-inflammatory and cytotoxic compounds. The results so far obtained indicate that C. oppositifolia leaves extract could significantly reduce the viability of THP-1 cells (IC50 = 6.2 ± 1.2 µg/mL), as well as the activation of both NF-κB and AP-1 at the concentration of 2 µg/mL. Our results indicate that Nepalese C. oppositifolia is a valuable source of anti-inflammatory and cytotoxic compounds. The phytochemical composition reported here can partially justify the traditional uses of C. oppositifolia in Nepal, especially in the treatment of inflammatory diseases, although further research will be needed to assess the full potential of this species.


Asunto(s)
Antiinflamatorios/farmacología , Lamiaceae/metabolismo , FN-kappa B/antagonistas & inhibidores , Extractos Vegetales/farmacología , Plantas Medicinales/metabolismo , Factor de Transcripción AP-1/antagonistas & inhibidores , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/toxicidad , Cromatografía Liquida , Flavonoides/análisis , Flavonoides/aislamiento & purificación , Humanos , Hidroxibenzoatos/análisis , Hidroxibenzoatos/aislamiento & purificación , Espectrometría de Masas , Metaboloma , Metanol , Nepal , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Hojas de la Planta/metabolismo , Células THP-1
5.
Adv Exp Med Biol ; 1052: 75-81, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29785482

RESUMEN

Ayurvedic medicines are often used in different formulations, the heavy metals, which are generally referred to as being toxic. In this work, we report on the physicochemical characterization and biological activity of some typical Ayurvedic drugs available in the market that contain arsenic, mercury and lead with the emphasis on their antibacterial performance. Among the formulations studied, some of the drugs with 'amorphous' texture (and higher solubility) were found quite active against some bacterial strains whereas the formulations possessing crystalline texture (and low solubility) were found practically ineffective. The moderate activity of some drugs against Gram-negative bacteria fairly suggested the presence of the small-sized polar molecules which was also supported by the FTIR spectroscopic data.


Asunto(s)
Antibacterianos/farmacología , Medicina Ayurvédica , Metales Pesados/farmacología , Antibacterianos/análisis , Arsénico/análisis , Arsénico/farmacología , Bacterias/efectos de los fármacos , Plomo/análisis , Plomo/farmacología , Mercurio/análisis , Mercurio/farmacología , Metales Pesados/análisis
6.
Phys Chem Chem Phys ; 18(29): 19655-67, 2016 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-27381062

RESUMEN

Copper oxide nanoparticles (nCOPs) having octahedral morphology, synthesized through hydrazine reduction reaction were employed to formulate an epoxy based novel nanocomposite. The synthesis of copper oxide nanoparticles was carried out in polyethylene glycol medium to enhance their interfacial adhesion with the epoxy matrix. The extent of conservation of the crystalline nature and octahedral morphology of the nCOP in its epoxy nanocomposites was confirmed by X-ray diffraction and electron microscopy analysis. The mechanical properties including tensile, impact, fracture toughness and surface hardness of epoxy-nCOP nanocomposites were evaluated as a function of nCOP content. The maximum enhancement in strength, modulus, impact strength, fracture toughness and surface hardness of epoxy-nCOP nanocomposites was observed for 5 phr nCOP content. This may be due to the strong interaction between the nCOP and epoxy chains at this composition arising from its fairly uniform dispersion. A quantitative measurement of constrained epoxy chains immobilized by the nCOP octahedra was carried out using dynamic mechanical analysis. The enhancement in the storage modulus is related to the amount of the added nCOP as well as the volume of the constrained epoxy chains in the proximity of nCOP. The behaviour of epoxy-nCOP nanocomposites in this study has been explained by proposing a mechanism based on the distribution of nCOP domains in the epoxy matrix and the existing volume of constrained epoxy chains.

7.
Adv Exp Med Biol ; 807: 23-32, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24619616

RESUMEN

In this paper, we present an overview of Ayurvedic Bhasmas as nanomedicine of herbo-metallic and mineral origin with particular attention to their structural aspects. We find, the Bhasmas as nanomedicines may offer a huge potential for designing new drugs employing the concept of nanotechnology. Thus, the standardization of fabrication process of these formulations is a crucial issue to be addressed. The structure and effectiveness of the Bhasmas as drugs depend largely on their processing history. Bhasmas are generally safe drugs for human beings in spite of the presence of seemingly toxic elements and compounds as indicated by recent studies using modern analytical techniques. Nevertheless, more systematic nanomaterialistic investigations on Bhasmas are recommended for gaining the complete and reliable composition-processing-structure-effectiveness picture of these drugs.


Asunto(s)
Medicina Ayurvédica , Nanomedicina , Humanos
8.
J Biomol Struct Dyn ; : 1-16, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38345021

RESUMEN

Iridoids commonly found in plants as secondary metabolites have been reported to possess significant biological activities such as anticancer, antioxidant, hypoglycemic, antimicrobial etc. The strong interactions of iridoids with cyclic-dependent kinase 8 (CDK8) protein could show inhibitory effects that could modulate tumour growth. From the molecular docking calculations, some iridoids interacted effectively with the target CDK8 protein (PDB ID: 5ICP) with better binding affinities of -9.1, -9.0, -9.0, -8.9 kcal/mol, than that observed for the native ligand with -8.7 kcal/mol and for the reference compound gemcitabine with -6.9 kcal/mol. The GI50 values (<5 µM) obtained from graph-based signatures showed activity in breast, colon, leukaemia, and renal cancer cell lines. The IC50 predictions as CDK2 inhibitors were greater than 10 µM with type I non-allosteric binding mode. The stability analysis of protein-ligand complex from 125 ns long molecular dynamics simulations showed moderately smooth trajectories and RSMD value around 5 Å for the docked ligands. The binding free energy changes up to -47.65 ± 5.97 kcal/mol from MMGBSA method and -30.33 ± 5.40 kcal/mol from MMPBSA method hinted at the spontaneous nature of the complex formation. Furthermore, geometrical evaluators like RMSF, Rg, SASA, and hydrogen bond count also corroborated with the structural stability of the complexes and the capacity of hit molecules to inhibit the target, indicating its therapeutic potential against cancer. The toxicity and drug-likeness from ADMET predictions suggested experimental verification and that the proposed candidates could be employed for further trials in the development of safer and more effective anticancer drugs.Communicated by Ramaswamy H. Sarma.

9.
J Ethnopharmacol ; 331: 118345, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38754645

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Justicia adhatoda L. is used as traditional medicine in Nepal to treat cough, asthma, and inflammatory disorders, and is indicated as "Asuro". Leaves are used worldwide as herbal medicine due to cardiotonic, expectorant, anti-asthmatic, and bronchodilatory properties. The aim of this work was to study the phytochemical composition of leaves of Nepalese J. adhatoda and assess their anti-inflammatory and antioxidant properties in vitro. MATERIALS AND METHODS: Secondary metabolites were extracted from dried leaves using methanol (JAME: J. adhatoda methanol extract). They were analysed by means of liquid chromatography coupled with multiple-stage mass spectrometry (LC-MSn). Anti-inflammatory potential was determined by the NF-κB and AP-1 inhibition assay, and DPPH, ABTS, and ß-carotene bleaching assays were performed to assess its antioxidant properties. RESULTS: JAME is a rich source of secondary metabolites, especially quinazoline alkaloids such as vasicine, vasicinone, vasicoline, and adhatodine. 7-Hydroxy derivatives of peganidine, vasicolinone, and adhatodine were also identified by means of MSn data and are here reported in J. adhatoda for the first time. JAME inhibited NF-κB and AP-1 expression in THP-1 cells to a greater extent than the positive control prednisolone. A moderate radical-quenching property was observed in DPPH and ABTS assays, but the anti-carotene bleaching activity was significantly higher than the reference BHT. CONCLUSIONS: To the best of our knowledge, this is the first insight into the phytochemical composition of Asuro leaves from Nepal and their bioactivity. Our results will contribute to the valorisation of this medicinal species still widely used in the traditional and complementary medicine.


Asunto(s)
Alcaloides , Antiinflamatorios , Antioxidantes , Género Justicia , FN-kappa B , Extractos Vegetales , Hojas de la Planta , Quinazolinas , Factor de Transcripción AP-1 , Hojas de la Planta/química , FN-kappa B/metabolismo , Antioxidantes/farmacología , Antioxidantes/aislamiento & purificación , Género Justicia/química , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Alcaloides/farmacología , Alcaloides/aislamiento & purificación , Factor de Transcripción AP-1/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Quinazolinas/farmacología , Quinazolinas/aislamiento & purificación , Humanos , Medicina Tradicional
10.
Nanoscale Adv ; 6(10): 2539-2568, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38752147

RESUMEN

Considering the rapidly increasing population, the development of new resources, skills, and devices that can provide safe potable water and clean energy remains one of the vital research topics for the scientific community. Owing to this, scientific community discovered such material for tackle this issue of environment benign, the new materials with graphene functionalized derivatives show significant advantages for application in multifunctional catalysis and energy storage systems. Herein, we highlight the recent methods reported for the preparation of graphene-based materials by focusing on the following aspects: (i) transformation of graphite/graphite oxide into graphene/graphene oxide via exfoliation and reduction; (ii) bioinspired fabrication or modification of graphene with various metal oxides and its applications in photocatalysis and storage systems. The kinetics of photocatalysis and the effects of different parameters (such as photocatalyst dose and charge-carrier scavengers) for the optimization of the degradation efficiency of organic dyes, phenol compounds, antibiotics, and pharmaceutical drugs are discussed. Further, we present a brief introduction on different graphene-based metal oxides and a systematic survey of the recently published research literature on electrode materials for lithium-ion batteries (LIBs), supercapacitors, and fuel cells. Subsequently, the power density, stability, pseudocapacitance charge/discharge process, capacity and electrochemical reaction mechanisms of intercalation, and conversion- and alloying-type anode materials are summarized in detail. Furthermore, we thoroughly distinguish the intrinsic differences among underpotential deposition, intercalation, and conventional pseudocapacitance of electrode materials. This review offers a meaningful reference for the construction and fabrication of graphene-based metal oxides as effective photocatalysts for photodegradation study and high-performance optimization of anode materials for LIBs, supercapacitors, and fuel cells.

11.
Int J Biomater ; 2023: 8541621, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36760230

RESUMEN

In this study, decellularized fish skin (DFS) scaffold decorated with silver nanoparticles was prepared for accelerating burn wound healing. The silver nanoparticles (AgNPs) synthesized by the green and facile method using Aloe vera leaf at different incubating times were characterized by using X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectroscopy, and Ultraviolet-Visible Spectroscopy (UV-Vis spectroscopy). The different characterizations confirmed that the sizes of AgNPs prepared by incubating for 6 hours and 12 hours were 29.1 nm and 35.2 nm, respectively. After that, the different concentrations of the smallest AgNPs were used to dope the DFS scaffold to determine the cell viability. Additionally, an agar well diffusion method was used to screen for antimicrobial activity. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were used to correlate the concentration of AgNPs with its bactericidal effect which was seen from 50 µg/ml. Then, the toxicity with human cells was investigated using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay with no significant cell viability from the concentration of 50 µg/ml to 200 µg/ml compared to the cocultured and commercial treatments.

12.
Heliyon ; 9(4): e15239, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37089299

RESUMEN

The synthesis and characterization of two new Schiff base ligands containing 1,2,4-triazole moieties and their oxovanadium(IV) complexes have been reported. The ligands and their complexes were studied by ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), electron paramagnetic resonance (EPR), X-ray diffraction (XRD), conductivity measurement, cyclic voltammetry (CV), and elemental analyses. The molar conductance of oxovanadium(IV) complexes were found to be relatively low, depicting their non-electrolytic nature. The XRD patterns reveal the size of particles to be 47.53 nm and 26.28 nm for the two complexes in the monoclinic crystal system. The molecular structures, geometrical parameters, chemical reactivity, stability, and frontier molecular orbital pictures were determined by density functional theory (DFT) calculations. The theoretical vibrational frequencies and EPR g-factors (1.98) were found to correlate well with the experimental values. A distorted square pyramidal geometry with C2 symmetry of the complexes has been proposed from experimental and theoretical results in a synergistic manner. The antimicrobial sensitivity of the ligands and their metal complexes assayed in vitro against four bacterial pathogens viz. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Salmonella Typhi showed that the oxovanadium(IV) complexes are slightly stronger antibacterial agents than their corresponding Schiff base precursors. The binding affinities obtained from the molecular docking calculations with the receptor proteins of bacterial strains (2EUG, 3UWZ, 4GVF, and 4JVD) showed that the Schiff bases and their oxovanadium(IV) complexes have considerable capacity inferring activeness for effective inhibition. The molecular dynamics simulation of a protein-ligand (4JVD-HL2) complex with the best binding affinity of -12.8 kcal/mol for 100 ns showed acceptable stability of the docked pose and binding free energy of -15.17 ± 2.29 kcal/mol from molecular mechanics-generalized Born surface area (MM-GBSA) calculations indicated spontaneity of the reaction. The outcome of the research shows the complementary role of computational methods in material characterization and provides an interesting avenue to pursue for exploring new triazole based Schiff's bases and its vanadium compounds for better properties.

13.
J Nanosci Nanotechnol ; 12(3): 1859-70, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22754991

RESUMEN

Polypropylene (PP)/ethylene-propylene rubber (EPR)/Montmorillonite ternary nanocomposites with a phase separated morphology were studied in this work. Wide angle X-ray diffraction (WAXD), small angle X-ray scattering (SAXS), atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to investigate the samples. One of the aim of this work was to separate the effects of rubber and clay content on the structure, morphology and mechanical properties of the samples. The presence of clay favored the formation of gamma phase and disrupted the lamellar framework. Clay had moreover a major role in shaping the phase separated morphology of the samples. Atomic Force Microscopy showed that the shear exerted by the clay layers was key for inducing a shish kebab morphology in the polymer matrix. Rubber content decreased the degree of crystallinity at a crystalline cell level and induced the formation of a double population of lamellar stacks. The mechanical properties of the samples primarily depended on rubber content, and they were secondarily tuned by the effect of clay. This synergistic effect allowed to obtain composites with increased stiffness, ductility and toughness, oppositely to what is frequently found.

14.
Biosensors (Basel) ; 12(7)2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35884262

RESUMEN

Taking the life of nearly 10 million people annually, cancer has become one of the major causes of mortality worldwide and a hot topic for researchers to find innovative approaches to demystify the disease and drug development. Having its root lying in microelectronics, microfluidics seems to hold great potential to explore our limited knowledge in the field of oncology. It offers numerous advantages such as a low sample volume, minimal cost, parallelization, and portability and has been advanced in the field of molecular biology and chemical synthesis. The platform has been proved to be valuable in cancer research, especially for diagnostics and prognosis purposes and has been successfully employed in recent years. Organ-on-a-chip, a biomimetic microfluidic platform, simulating the complexity of a human organ, has emerged as a breakthrough in cancer research as it provides a dynamic platform to simulate tumor growth and progression in a chip. This paper aims at giving an overview of microfluidics and organ-on-a-chip technology incorporating their historical development, physics of fluid flow and application in oncology. The current applications of microfluidics and organ-on-a-chip in the field of cancer research have been copiously discussed integrating the major application areas such as the isolation of CTCs, studying the cancer cell phenotype as well as metastasis, replicating TME in organ-on-a-chip and drug development. This technology's significance and limitations are also addressed, giving readers a comprehensive picture of the ability of the microfluidic platform to advance the field of oncology.


Asunto(s)
Microfluídica , Neoplasias , Biomimética , Desarrollo de Medicamentos , Humanos , Dispositivos Laboratorio en un Chip , Neoplasias/diagnóstico , Neoplasias/patología
15.
Environ Health Insights ; 16: 11786302221104348, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35694428

RESUMEN

Background: The pandemic of Coronavirus Disease 2019 (COVID-19), one of the most infectious diseases in the modern history, is caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and has had a profound health and economic toll, globally. This paper identifies the overall health status associated with COVID-19 pandemic in all 7 provinces of Nepal, a developing country in South Asia, analyzing data from January 2020 to February 2022. It focuses on the SARS-CoV-2 prevalence, transmission through wastewater and other routes, diagnostics, treatment options, and alternative medicines, thereby offering key perspectives for its management. Materials and Methods: Studies regarding coronavirus spanning the 2017 to 2022 period were searched on the web, Nepalese database, and Web of Science. Refined criteria included SARS-CoV-2 in wastewater of Nepal or worldwide. Demographic data (sex, age-group, and geographic location) were also obtained from websites and relevant reports of the Ministry of Health and Population (MOHP) of Nepal, ranging from January 2020 to February 2022. Moreover, trends concerning lockdown, business, and border activities in Nepal between February 2020 and October 2020 were evaluated. The viral dissemination pathways, diagnosis, and available treatment options, including the Ayurvedic medicine, were also examined. Results: Aerosols generated during the hospital, industrial, recreational, and household activities were found to contribute to the propagation of SARS-CoV-2 into environmental wastewater, thereby putting the surrounding communities at risk of infection. When lockdown ended and businesses opened in October 2020, the number of active cases of COVID-19 increased exponentially. Bagmati Province had the highest number of cases (53.84%), while the remaining 6 provinces tallied 46.16%. Kathmandu district had the highest number of COVID-19 cases (138, 319 cases), while Manang district had the smallest number of infections (81 cases). The male population was found to be predominantly infected (58.7%). The most affected age groups were the 31 to 40 years old males (25.92%) and the 21 to 30 years old females (26.85%). Conclusion: The pandemic impacted the public health and economic growth in our study duration. SARS-CoV-2 was prevalent in the wastewater of Nepal. The Terai districts and the megacities were mostly affected by SARS-CoV-2 infections. Working-age groups and males were identified as the highest risk groups. More investigations on the therapeutic and alternative cures are recommended. These findings may guide the researchers and professionals with handling the COVID-19 challenges in developing countries such as Nepal and better prepare for future pandemics.

16.
Front Cell Dev Biol ; 9: 639233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33693004

RESUMEN

Cell-free DNA (cfDNA) is easily accessible in peripheral blood and can be used as biomarkers for cancer diagnostics, prognostics, and therapeutics. The applications of cfDNA in various areas of cancer management are attracting attention. In this review article, we discuss the potential relevance of using cfDNA analysis in clinical oncology, particularly in cancer screening, early diagnosis, therapeutic evaluation, monitoring disease progression; and determining disease prognosis.

17.
J Trop Med ; 2020: 4046703, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32908547

RESUMEN

INTRODUCTION: Group B streptococci (GBS) are globally recognized as one of the leading causes of neonatal sepsis and meningitis and is also known to cause adverse pregnancy outcomes such as stillbirths and miscarriages. Thus, detailed investigation of GBS in pregnant women has special significance in public health related researches. OBJECTIVES: The present study is aimed at evaluating the prevalence of GBS colonization among pregnant women in Kathmandu city. METHODS: The study was carried out among 125 pregnant women at their trimester (35-37 weeks) (during the time period between January and June in 2018). The prevalence was determined by the culture method in HiCrome Strep B Selective Agar Base and then by using the PCR technique. The serotypes were evaluated by multiplex PCR analysis, while the antibiotics susceptibility tests were performed using the disk diffusion method. RESULTS: Among 125 samples studied, GBS were recorded in 24 samples (implying a prevalence of 19.2%). Furthermore, using the multiplex PCR, among 24 GBS-positive samples, 13 (54.17%) were found to be typeable while 11 (45.83%) were nontypeable. The most abundant serotype recorded in this study was type III (33.33) while the serotypes IV, V, VI, VII, and VIII were not found. CONCLUSION: The isolates were sensitive towards some antibiotics such as linezolid and ceftriaxone 100%, whereas penicillin 50% and vancomycin 75% but were resistant to tetracycline and ertapenem. Serotype III was found to be predominant in the samples collected during the study period. The observed prevalence was significantly associated with the gestational period, whereas no relationship was found for other risk factors.

18.
Polymers (Basel) ; 13(1)2020 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-33383639

RESUMEN

The chemical modification (namely the epoxidation) of a star shaped block copolymer (BCP) based on polystyrene (PS) and polybutadiene (PB) and its effect on structural and mechanical properties of the polymer were investigated. Epoxidation degrees of 37 mol%, 58 mol%, and 82 mol% were achieved by the reaction of the copolymer with meta-chloroperoxy benzoic acid (m-CPBA) under controlled conditions. The BCP structure was found to change from lamellae-like to mixed-type morphologies for intermediate epoxidation level while leading to quite ordered cylindrical structures for the higher level of chemical modification. As a consequence, the glass transition temperature (Tg) of the soft PB component of the BCP shifted towards significantly higher temperature. A clear increase in tensile modulus and tensile strength with a moderate decrease in elongation at break was observed. The epoxidized BCPs are suitable as reactive templates for the fabrication of nanostructured thermosetting resins.

19.
Front Pharmacol ; 11: 722, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32528284

RESUMEN

Cancer has been a major global health problem due to its high morbidity and mortality. While many chemotherapy agents have been studied and applied in clinical trials or in clinic, their application is limited due to its toxic side effects and poor tolerability. Monoclonal antibodies specific to the PD-1 and PD-L1 immune checkpoints have been approved for the treatment of various tumors. However, the application of PD-1/PD-L1 inhibitors remains suboptimal and thus another strategy comes in to our sight involving the combination of checkpoint inhibitors with other agents, enhancing the therapeutic efficacy. Various novel promising approaches are now in clinical trials, just as icing on the cake. This review summarizes relevant investigations on combinatorial therapeutics based on PD-1/PD-L1 inhibition.

20.
J Ayurveda Integr Med ; 11(3): 256-260, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32798193

RESUMEN

BACKGROUND: Ghr̥ta murcchana is a process of pre-treatment recommended in Ayurveda to purify ghee before it can be used for siddha ghr̥ta which is claimed to improve the properties of the ghee in general and that of the prepared siddha ghr̥ta. OBJECTIVE: This work is aimed at studying the physiochemical properties of ghee and murcchita ghr̥ta in order to understand the impact of ghr̥ta murcchana process. MATERIALS AND METHODS: Ghee and murcchita ghr̥ta were prepared from the milk of local Pahadi, Jersey and Holstein cows. The samples were characterized by FTIR spectroscopy, differential scanning calorimetry and free fatty acid measurements. RESULTS: Among the samples studied, the Holstein cow ghee was found to contain the least amount of free acid (1.34%) whereas ghr̥ta murcchana process led to further decrease in the free acid content polymorphism was observed in the samples as evidenced by multiple melting points. In most cases, murcchita ghr̥ta was found to contain less solid fat than the corresponding ghee implying that the high melting compound was converted to low melting one during the process. CONCLUSION: The observed lowering of free fatty acid and solid fat contents in the ghee samples may provide a possible validation to the performance enhancement of the ghr̥ta murcchana process.

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