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1.
Front Microbiol ; 15: 1338100, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38318336

RESUMEN

Wastewater-based epidemiology (WBE) has been used for monitoring infectious diseases like polio, hepatitis, etc. since the 1940s. It is also being used for tracking the SARS-CoV-2 at the population level. This article aims to compile and assess the information for the qualitative and quantitative detection of the SARS-CoV-2 in wastewater. Based on the globally published studies, we highlight the importance of monitoring SARS-CoV-2 presence/detection in the wastewater and concurrently emphasize the development of early surveillance techniques. SARS-CoV-2 RNA sheds in the human feces, saliva, sputum and mucus that ultimately reaches to the wastewater and brings viral RNA into it. For the detection of the virus in the wastewater, different detection techniques have been optimized and are in use. These are based on serological, biosensor, targeted PCR, and next generation sequencing for whole genome sequencing or targeted amplicon sequencing. The presence of the SARS-CoV-2 RNA in wastewater could be used as a potential tool for early detection and devising the strategies for eradication of the virus before it is spread in the community. Additionally, with the right and timely understanding of viral behavior in the environment, an accurate and instructive model that leverages WBE-derived data may be created. This might help with the creation of technological tools and doable plans of action to lessen the negative effects of current viral epidemics or future potential outbreaks on public health and the economy. Further work toward whether presence of viral load correlates with its ability to induce infection, still needs evidence. The current increasing incidences of JN.1 variant is a case in point for continued early detection and surveillance, including wastewater.

2.
Heliyon ; 9(7): e18214, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37501975

RESUMEN

Introduction: For generations, the inhabitants of Meghalaya have relied on medicinal plants to maintain the health of their livestock and treat various illnesses that may afflict their animals. Due to the lack of survey for use and documentation, these plants have never been undertaken. Therefore, it is imperative to explore the diversity, utilization, and phytochemical profile of these plants and quantitatively analyse the data to identify important medicinal plants. By doing so, we can better understand the potential of these plants for developing novel drugs. Methods: Frequent field trips were made for the collection of ethnoveterinary data of medicinal plants from local animal-keepers, traditional healers (THs) and inhabitants of different age groups. This information was gathered through semi-structured interviews, individual discussions, direct field-use observation, and questionnaires. A total of 52 informants (35 females and 17 males) were interviewed from seven rural villages and the information obtained from them were quantitatively analysed using the informant consensus factor (ICF), and fidelity level (FL). Additionally, for each documented plant, available published literature was extensively surveyed to identify the presence of bioactive chemical compounds responsible for their therapeutic effects. Results: During the present study, a total 96 plants, distributed into 87 genera and 43 families were identified and recorded for their use in ethnoveterinary practices against more than 25 diseases. Out of the recorded plant species, the Fabaceae family was found to be the most dominant with seven species, followed by Poaceae and Lamiaceae with six species each, and Moraceae with five species. The leaves (50.00%) and seeds (12.50%) were the most frequently used plant parts, while the paste (30 species) was the common mode of application. Aegle marmelos Correa exhibited a fidelity level (FL) of 100% for indigestion, while Tagetes erecta L. had a fidelity level of 94.11% for wound treatment, making them the most promising candidates for further study. The highest FIC value of 1.00 was recorded for the treatment of neurological disorder (1.00), followed by foot and mouth disease (FIC 0.91), which depicted that some species were frequently utilized to treat multiple livestock ailments. Conclusion: The study presents trustworthy information about medicinal plants and their associated indigenous ethnoveterinary knowledge. It has been scientifically proven that these plants contain bioactive compounds responsible for their therapeutic properties. However, this knowledge is in danger of being lost due to factors like socioeconomic changes, environmental and technological alterations, and lack of interest from younger generations. Therefore, it is essential to document this empirical folklore knowledge systematically and take measures to protect and conserve it.

6.
Chem Biodivers ; 20(2): e202200718, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36562215

RESUMEN

Three underutilized leafy vegetables Sarcochlamys pulcherrima (Roxb.) Gaudich (SP), Ipomoea aquatica Forssk. (IA) and Zanthoxylum rhetsa (Roxb.) DC (ZR) were extracted with different solvents viz. 95 % ethyl alcohol, methanol and hot water. The extracts were evaluated for their antioxidant potential via DPPH, ABTS and FRAP assay along with electroanalytical studies using cyclic voltammetry. The antidiabetic potential was determined by recording their α-amylase and α-glucosidase inhibitory assay. The total phenolic content (TPC), total flavonoid content (TFC) and the liquid chromatography-mass spectrometry (LC/MS) based phytochemical profiles of the extracts were also determined. All three extracts of SP exhibited significant antioxidant capacity. The antidiabetic potential of the IA and ZR extracts was found to be higher than or at par with that of standard acarbose. LC/MS studies reveal the presence of hitherto reported antioxidant and antidiabetic compounds like gamma-aminobutyric acid, cinnamic acid, caffeic acid, α-viniferin, piperlonguminine, niacin, kaempferol, etc., in the extracts.


Asunto(s)
Antioxidantes , Hipoglucemiantes , Antioxidantes/química , Plantas Comestibles , Extractos Vegetales/química , India
7.
Indian J Med Microbiol ; 43: 58-65, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36371334

RESUMEN

PURPOSE: Seroepidemiology and genomic surveillance are valuable tools to investigate infection transmission during a pandemic. North East (NE) India is a strategically important region being the gateway connecting the country with Southeast Asia. Here, we examined the spread of SARS-CoV-2 in NE India during the first and second waves of COVID-19 using serological and whole genome sequencing approaches. METHODS: qRT-PCR analysis was performed on a selected population (n â€‹= â€‹16,295) from June 2020 to July 2021, and metadata was collected. Immunoassays were studied (n â€‹= â€‹2026) at three-time points (August 2020, February 2021, and June 2021) and in a cohort (n â€‹= â€‹35) for a year. SARS-CoV-2 whole genomes (n â€‹= â€‹914) were sequenced and analyzed with those obtained from the databases. RESULTS: Test positivity rates (TPR) in the first and second waves were 6.34% and 6.64% in Assam, respectively, and a similar pattern was observed in other NE states. Seropositivity in the three time points was 10.63%, 40.3%, and 46.33%, respectively, and neutralizing antibody prevalence was 90.91%, 52.14%, and 69.30%, respectively. Persistence of pan-IgG-N SARS-CoV-2 antibody for over a year was observed among three subjects in the cohort group. Normal variants dominated the first wave, while B.1.617.2 and AY-sublineages dominated the second wave in the region. The prevalence of the variants co-related well with high TPR and seropositivity rate in the region and identified mostly among vaccinated individuals. CONCLUSION: The COVID-19 first wave in the region witnessed low transmission with the evolution of diverse variants. Seropositivity increased during the study period with over half of the individuals carrying neutralizing antibodies against SARS-CoV-2. High infection and seroprevalence in NE India during the second wave were associated with the dominant emergence of variants of concern.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Estudios Seroepidemiológicos , SARS-CoV-2/genética , COVID-19/epidemiología , Genómica , India/epidemiología , Anticuerpos Neutralizantes
8.
Front Med (Lausanne) ; 10: 1294699, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38288302

RESUMEN

Introduction: Recombination serves as a common strategy employed by RNA viruses for their genetic evolution. Extensive genomic surveillance during the COVID-19 pandemic has reported SARS-CoV-2 Recombinant strains indicating recombination events during the viral evolution. This study introspects the phenomenon of genome recombination by tracing the footprint of prominent lineages of SARS-CoV-2 at different time points in the context of on-going evolution and emergence of Recombinants. Method: Whole genome sequencing was carried out for 2,516 SARS-CoV-2 (discovery cohort) and 1,126 (validation cohort) using nasopharyngeal samples collected between the time period of March 2020 to August 2022, as part of the genomic surveillance program. The sequences were classified according to the different lineages of SARS-CoV-2 prevailing in India at respective time points. Results: Mutational diversity and abundance evaluation across the 12 lineages identified 58 Recombinant sequences as harboring the least number of mutations (n = 111), with 14 low-frequency unique mutations with major chunk of mutations coming from the BA.2. The spontaneously/dynamically increasing and decreasing trends of mutations highlight the loss of mutations in the Recombinants that were associated with the SARS-CoV-2 replication efficiency, infectivity, and disease severity, rendering them functionally with low infectivity and pathogenicity. Linkage disequilibrium (LD) analysis revealed that mutations comprising the LD blocks of BA.1, BA.2, and Recombinants were found as minor alleles or as low-frequency alleles in the LD blocks from the previous SARS-CoV-2 variant samples, especially Pre-VOC. Moreover, a dissipation in the size of LD blocks as well as LD decay along with a high negative regression coefficient (R squared) value was demonstrated in the Omicron and BA.1 and BA.2 lineages, which corroborated with the breakpoint analysis. Conclusion: Together, the findings help to understand the evolution and emergence of Recombinants after the Omicron lineages, for sustenance and adaptability, to maintain the epidemic spread of SARS-CoV-2 in the host population already high in immunity levels.

12.
J Colloid Interface Sci ; 587: 446-456, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33383434

RESUMEN

Tuning composition of Pd-based bimetallic electrocatalysts of high stability and durability is of great importance in energy-related reactions. This study reports the remarkable electrocatalytic performance of carbon-supported bimetallic Pd-Cu alloy nanoparticles (NPs) towards formic acid oxidation (FAO) and oxygen reduction reaction (ORR). Among various bimetallic compositions, Pd3Cu/C alloy NPs exhibits the best FAO and ORR activity. During FAO reaction, Pd3Cu/C alloy NPs exhibits a peak with a current density of 28.33 mA cm-2 and a potential of 0.2 V (vs. Ag/AgCl) which is higher than that of the other PdCu compositions and standard 20 wt% Pd/C catalyst. Meanwhile, the onset potential (-0.09 V), half-wave potential (-0.18 V), limiting current density at 1600 rpm (-4.9 mA cm-2) and Tafel slope (64 mV dec-1) values of Pd3Cu/C alloy NPs validate its superiority over the conventional 20 wt% Pt/C catalyst for ORR. Experimental and DFT studies have confirmed that the enhanced activity can be attributed to the electronic effect that arises after Cu alloying which causes a downshift of Pd d-band center and structural effect that produces highly dispersed NPs over the carbon matrix with high electrochemically active surface area.

13.
Langmuir ; 36(49): 15141-15152, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33256414

RESUMEN

Herein, we report the synthesis and bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities of a CuOx-CeO2/C electrocatalyst (EC) with rich oxide-oxide and oxide-carbon interfaces. It not only demonstrates a smaller Tafel slope (65 mV dec-1) and higher limiting current density (-5.03 mA cm-2) but also exhibits an onset potential (-0.10 V vs Ag/AgCl) comparable to that of benchmark Pt/C. Besides undergoing the favorable direct four-electron ORR pathway, it unveils a loss of 23% of its initial current after 6 h of a stability test and a negative shift of 4 mV in the half-wave potential after the accelerated durability test compared to the corresponding current loss of 28% and negative shift of 20 mV for Pt/C. It also reveals remarkable OER activity in an alkaline medium with a low onset potential (0.20 V) and a smaller Tafel slope (177 mV dec-1). The bifunctional ORR/OER activity of CuOx-CeO2/C EC can be ascribed to the synergistic effects, its unique structure with enriched oxygen vacancies owing to the presence of Ce4+/Ce3+, robust oxide-oxide and oxide-carbon heterointerfaces, and homogeneous dispersion of oxides over the carbon bed, which facilitates faster electronic conduction.

14.
World J Hepatol ; 12(12): 1182-1197, 2020 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-33442447

RESUMEN

The 2019 novel coronavirus disease (COVID-19) pandemic due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a serious threat to global public health. Although primarily, the infection causes lung injury, liver enzyme abnormalities have also been reported to occur during the course of the disease. We conducted an extensive literature review using the PubMed database on articles covering a broad range of issues related to COVID-19 and hepatic injury. The present review summarizes available information on the spectrum of liver involvement, the possible mechanisms and risk factors of liver injury due to SARS-CoV-2 infection, and the prognostic significance of the presence of liver injury. Hopefully, this review will enable clinicians, especially the hepatologists, to understand and manage the liver derangements they may encounter in these patients better and provide guidance for further studies on the liver injury of COVID-19.

15.
ACS Omega ; 4(2): 3329-3340, 2019 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-31459548

RESUMEN

This work describes a practical methodology for C-C bond formation reactions with the aid of biogenic palladium nanoparticles, which are synthesized by using phytochemicals extracted from two common plant species. Comparative studies have been done on the activity of two plant species (Ocimum sanctum and Aloe vera) in generation of palladium nanoparticles via ex situ and in situ methods. The structural and morphological characteristics of the nanoparticles are examined by UV/visible spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy analyses. We have observed a significant influence of the substrates on the catalytic activity of the palladium nanoparticles in Sonogashira and Suzuki cross-coupling reactions.

16.
IET Nanobiotechnol ; 13(1): 18-22, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30964032

RESUMEN

Green synthesis of nanoparticles has gained importance due to its eco-friendly, low toxicity and cost effective nature. This study deals with the biosynthesis of silver nanoparticles (AgNPs) from the bark extract of Amentotaxus assamica. The AgNPs have been synthesised by reducing the silver ions into stable AgNPs using the bark extract of Amentotaxus assamica under the influence of sunlight irradiation. The characterisation of the biosynthesised AgNPs was carried out by UV-vis spectroscopy, X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis. The UV-vis spectrum showed a broad peak at 472 nm. Also, the XRD confirmed the crystalline structure of the AgNPs. Moreover, the SEM analysis revealed that the biosynthesised AgNPs were spherical in shape. Also, dynamic light scattering techniques were used to evaluate the size distribution profile of the biosynthesised AgNPs. Furthermore, the biosynthesised AgNPs showed a prominent inhibitory effect against both Escherichia coli (MTCC 111) and Staphylococcus aureus (MTCC 97). Thus the biosynthesis of AgNPs from the bark extract of Amentotaxus assamica is found to eco-friendly way of producing AgNPs compared to chemical method.


Asunto(s)
Antibacterianos , Nanopartículas del Metal/química , Plata/química , Taxaceae/química , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Tecnología Química Verde , Corteza de la Planta/química , Extractos Vegetales/química , Staphylococcus aureus/efectos de los fármacos
17.
Chem Rec ; 19(2-3): 462-473, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30117656

RESUMEN

This account provides an overview of current research activities on nanoparticles containing the earth-abundant and inexpensive element copper (Cu) and Cu-based nanoparticles, especially in the field of environmental catalysis. The different synthetic strategies with possible modification of the chemical/ physical properties of these nanoparticles using such strategies and/or conditions to improve catalytic activity are presented. The design and development of support and/or bimetallic systems (e. g., alloys, intermetallic, etc.) are also included. Herein, we report synthetic approaches of Cu and Cu-based nanoparticles (monometallic copper, bimetallic copper and copper (II) oxide nanoparticles/nanostructures) and impregnation of such nanoparticles onto support material (e. g., Co3 O4 nanostructure), along with their applications as environmental catalyst for various oxidation and reduction reactions. Finally, this account provides necessary advances and perspectives of Cu-based nanoparticles in the environmental catalysis.

18.
ACS Omega ; 3(5): 5327-5335, 2018 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31458742

RESUMEN

The development of a green and sustainable synthetic methodology still remains a challenge across the globe. Encouraging the prevailing challenge, herein, we have synthesized Pd nanoparticles (Pd NPs) in a green and environmentally viable route, using the extract of waste papaya peel without the assistance of any reducing agents, high-temperature calcination, and reduction procedures. The biomolecules present in the waste papaya peel extract reduced Pd(II) to nanosize Pd(0) in a one-pot green and sustainable process. As a catalyst, the new Pd NPs offer a simple and efficient methodology in direct Suzuki-Miyaura and Sonogashira coupling with excellent yields under mild reaction conditions.

19.
ACS Omega ; 3(6): 7086-7095, 2018 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31458870

RESUMEN

A series of potassium salt-loaded MgAl hydrotalcites were synthesized by wet impregnation of KNO3, KF, KOH, K2CO3, and KHCO3 salts over calcined MgAl hydrotalcite (Mg-Al = 3:1). The samples were characterized by X-ray diffraction, Fourier transform infrared, thermogravimetry-differential thermal analysis, scanning electron microscopy, and N2 absorption-desorption techniques to investigate their structural properties. The results showed formation of well-developed hydrotalcite phase and reconstruction of layered structure after impregnation. The prepared hydrotalcites possess mesopores and micropores having pore diameters in the range of 3.3-4.0 nm and Brunauer-Emmett-Teller surface area 90-207 m2 g-1. Base strengths calculated from Hammett indicator method were found increasing after loading salts, where KOH-loaded hydrotalcite showed base strength in the range of 12.7 < H- < 15, which was found to be the preferred catalyst. Subsequently, KOH loading was increased from 10 to 40% (w/w) and catalytic activity was evaluated for the Knoevenagel condensation reaction at room temperature. Density functional theory calculations show that among all of the oxygen atoms present in the hydrotalcite, the O atom attached to the K atom has the highest basic character. In this study, 10% KOH-loaded hydrotalcite showing 99% conversion and 100% selectivity was selected as the preferred catalyst in terms of base strength, stability, and catalytic efficiency.

20.
J Colloid Interface Sci ; 486: 46-57, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27693520

RESUMEN

The present work reports a surfactant-free, economically feasible chemical route to synthesize bimetallic CuPd alloy nanoparticles under hydrothermal condition. The structural and morphological characterizations of the nanoparticles are carried out by XRD, SEM/EDX, TEM, XPS and BET surface area analyses. The synthetic strategy comprises of 9:1 molar composition of Cu2+ and Pd2+ salt in the aqueous solution. The size of the nanoparticles isca. 3-4nmwith very notable specific surface area of 298m2g-1. The synthesized nanoparticles exhibit excellent catalytic performance towards the aqueous phase reduction of 4-nitrophenol and 4-nitroaniline in the presence of NaBH4 as a reducing agent. Furthermore the CuPd alloy nanoparticles also demonstrate remarkable activity towards reductive conversion of toxic Cr(VI) to less toxic Cr(III) at room temperature. Bimetallic CuPd alloy nanoparticles are catalytically more active and exhibit good recyclability in comparison to the monometallic Cu and Pd due to synergistic effect.

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