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1.
ACS Appl Bio Mater ; 6(12): 5644-5661, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37993284

RESUMO

In this work, the glycine-based acryloyl monomer is polymerized to obtain a neurogenic polymeric hydrogel for regenerative applications. The synthesized poly(N-acryloylglycine-acrylamide) [poly(NAG-b-A)] nanohydrogel exhibits high swelling (∼1500%) and is mechanically very stable, biocompatible, and proliferative in nature. The poly(NAG-b-A) nanohydrogel provides a stable 3D extracellular mimetic environment and promotes healthy neurite growth for primary cortical neurons by facilitating cellular adhesion, proliferation, actin filament stabilization, and neuronal differentiation. Furthermore, the protective role of the poly(NAG-b-A) hydrogel for the neurons in oxidative stress conditions is revealed and it is found that it is a clinically relevant material for neuronal regenerative applications, such as for promoting nerve regeneration via GSK3ß inhibition. This hydrogel additionally plays an important role in modulating the biological microenvironment, either as an agonist and antagonist or as an antioxidant. Furthermore, it favors the physiological responses and eases the neurite growth efficiency. Additionally, we found out that the conversion of glycine-based acryloyl monomers into their corresponding polymer modulates the mechanical performance, mimics the cellular microenvironment, and accelerates the self-healing capability due to the responsive behavior towards reactive oxygen species (ROS). Thus, the p(NAG-b-A) hydrogel could be a potential candidate to induce neuronal regeneration since it provides a physical cue and significantly boosts neurite outgrowth and also maintains the microtubule integrity in neuronal cells.


Assuntos
Hidrogéis , Neuritos , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Neuritos/metabolismo , Acrilamida , Estresse Oxidativo , Microambiente Celular , Polímeros/farmacologia , Polímeros/metabolismo , Glicina/farmacologia
2.
Phys Rev E ; 108(4): L042101, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37978665

RESUMO

We report on reentrance in the random-field Ising and Blume-Capel models, induced by an asymmetric bimodal random-field distribution. The conventional continuous line of transitions between the paramagnetic and ferromagnetic phases, the λ-line, is wiped away by the asymmetry. The phase diagram, then, consists of only first-order transition lines that always end at ordered critical points. We find that, while for symmetric random-field distributions there is no reentrance, the asymmetry in the random-field results in a range of temperatures for which magnetization shows reentrance. While this does not give rise to an inverse transition in the Ising model, for the Blume-Capel model, however, there is a line of first-order inverse phase transitions that ends at an inverse-ordered critical point. We show that the location of the inverse transitions can be inferred from the ground-state phase diagram of the model.

3.
mSystems ; 8(6): e0074523, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37882544

RESUMO

IMPORTANCE: Our study investigated how a traditional drink called Apong, made from fermented rice, affects the gut and health of the Mishing community in India. We compared two groups of people who drink Apong to a group of people who do not drink it. To accomplish this, we studied the gut bacteria, fecal metabolites, and blood samples of the participants. It was found that the people who drank Apong had higher blood pressure but lower blood sugar and protein levels than people who did not drink it. We also found that the gut microbiome composition of people who drank Apong was different from those who did not drink it. Moreover, people who drank Apong had lower levels of isovaleric acid in their feces. Overall, this study shows that a traditional drink like Apong can affect the gut bacteria of a community.


Assuntos
Microbioma Gastrointestinal , Hipertensão , Humanos , Bactérias , Bebidas Fermentadas , Fezes/microbiologia
4.
Traffic ; 24(12): 587-609, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37846526

RESUMO

In hepatocytes, the Wilson disease protein ATP7B resides on the trans-Golgi network (TGN) and traffics to peripheral lysosomes to export excess intracellular copper through lysosomal exocytosis. We found that in basal copper or even upon copper chelation, a significant amount of ATP7B persists in the endolysosomal compartment of hepatocytes but not in non-hepatic cells. These ATP7B-harbouring lysosomes lie in close proximity of ~10 nm to the TGN. ATP7B constitutively distributes itself between the sub-domain of the TGN with a lower pH and the TGN-proximal lysosomal compartments. The presence of ATP7B on TGN-lysosome colocalising sites upon Golgi disruption suggested a possible exchange of ATP7B directly between the TGN and its proximal lysosomes. Manipulating lysosomal positioning significantly alters the localisation of ATP7B in the cell. Contrary to previous understanding, we found that upon copper chelation in a copper-replete hepatocyte, ATP7B is not retrieved back to TGN from peripheral lysosomes; rather, ATP7B recycles to these TGN-proximal lysosomes to initiate the next cycle of copper transport. We report a hitherto unknown copper-independent lysosomal localisation of ATP7B and the importance of TGN-proximal lysosomes but not TGN as the terminal acceptor organelle of ATP7B in its retrograde pathway.


Assuntos
Cobre , Lisossomos , Cobre/metabolismo , ATPases Transportadoras de Cobre/metabolismo , Transporte Proteico , Lisossomos/metabolismo , Exocitose
5.
Metallomics ; 15(9)2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37660282

RESUMO

Mutational inactivation of the P-type Cu-ATPase ATP7B interferes with its cellular functions to varying extent leading to varied cellular phenotypes. Wilson's disease (WD) primarily affects organs composed of polarized/differentiated epithelial cells. Therefore, phenotypic variability might differ depending on the polarization/differentiation of the cells. The present study investigates the intracellular stability and localization of ATP7B harboring WD mutations in both unpolarized/undifferentiated and polarized/differentiated cell-based models. Green fluorescent protein (GFP)-ATP7B harboring the WD causing mutations, N41S, S653Y, R778Q, G1061E, H1069Q, S1423N, S1426I, and T1434M, are included for investigation. The C-terminal WD mutations (S1423N, S1426I, and T1434M), exhibit distinct localization and Cu(I) responsive anterograde and retrograde trafficking in undifferentiated/unpolarized vs. differentiated/polarized cells. While basal localization of the S1423N mutant gets corrected in the differentiated glia, its Cu(I) responsive anterograde and retrograde trafficking behavior is not identical to the wild-type. But localization and trafficking properties are completely rescued for the S1426I and T1434M mutants in the differentiated cells. Comprehensive meta-analysis on the effect of the reported C-terminal mutations on patient phenotype and cultured cells demonstrate discrete regions having distinct effects. While mutations in the proximal C-terminus affect ATP7B stability, the present study shows that the distal region dictates cell-specific Trans Golgi Network (TGN) localization and exit. The localization and export properties are corrected in the differentiated cells, which is a plausible mechanism for the milder phenotype exhibited by these mutations. It highlights the critical role of the C-terminus in cell-specific TGN retention and exit of ATP7B.


Assuntos
Degeneração Hepatolenticular , Humanos , Degeneração Hepatolenticular/genética , Complexo de Golgi , Diferenciação Celular/genética , Proteínas de Fluorescência Verde , Mutação
6.
Proc Natl Acad Sci U S A ; 120(33): e2305465120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549252

RESUMO

Microbes evolve rapidly by modifying their genomes through mutations or through the horizontal acquisition of mobile genetic elements (MGEs) linked with fitness traits such as antimicrobial resistance (AMR), virulence, and metabolic functions. We conducted a multicentric study in India and collected different clinical samples for decoding the genome sequences of bacterial pathogens associated with sepsis, urinary tract infections, and respiratory infections to understand the functional potency associated with AMR and its dynamics. Genomic analysis identified several acquired AMR genes (ARGs) that have a pathogen-specific signature. We observed that blaCTX-M-15, blaCMY-42, blaNDM-5, and aadA(2) were prevalent in Escherichia coli, and blaTEM-1B, blaOXA-232, blaNDM-1, rmtB, and rmtC were dominant in Klebsiella pneumoniae. In contrast, Pseudomonas aeruginosa and Acinetobacter baumannii harbored blaVEB, blaVIM-2, aph(3'), strA/B, blaOXA-23, aph(3') variants, and amrA, respectively. Regardless of the type of ARG, the MGEs linked with ARGs were also pathogen-specific. The sequence type of these pathogens was identified as high-risk international clones, with only a few lineages being predominant and region-specific. Whole-cell proteome analysis of extensively drug-resistant K. pneumoniae, A. baumannii, E. coli, and P. aeruginosa strains revealed differential abundances of resistance-associated proteins in the presence and absence of different classes of antibiotics. The pathogen-specific resistance signatures and differential abundance of AMR-associated proteins identified in this study should add value to AMR diagnostics and the choice of appropriate drug combinations for successful antimicrobial therapy.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Escherichia coli/genética , beta-Lactamases/genética , beta-Lactamases/farmacologia , Proteômica , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana
7.
Heliyon ; 9(6): e16666, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37303536

RESUMO

Using daily yield data of 14 sovereign bond markets from emerging and developed economies from July 10, 2000, to July 10, 2022, we examine their scaling properties using generalized Hurst exponent and spectral density analysis and investigate the connectedness based on a network analysis approach. We consider the yields of 2-year and 10-year bond yields to investigate the scaling properties for short- and long-term sovereign bonds. This selection also allows us to examine sovereign bond spreads with respect to the USA. We also use regularized partial correlation network analysis to connect different countries in communities based on yields. We find that the scaling behavior of the bond yields for both terms fits well using the Hurst exponent and spectral analysis confirms this finding. Moreover, we also find that even though bonds in both cohorts show anti-persistent behavior except that of the USA, the developed economies' bond yields are relatively less anti-persistent as compared to those of emerging economies. The networks of both the 2-year and 10-year yields indicate community formation in various countries which provides diversification benefits to the investors. Most of the emerging countries are classified into one community in the long-tenure bonds as well but this concentration is more evident in the short-tenure bonds.

8.
ACS Omega ; 8(22): 19413-19424, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37305291

RESUMO

The toxic nature of inorganic nanostructured materials as photocatalysts is often not accounted for in traditional wastewater treatment reactions. Particularly, some inorganic nanomaterials employed as photocatalysts may release secondary pollutants in the form of ionic species that leach out due to photocorrosion. In this context, this work is a proof-of-concept study for exploring the environmental toxicity effect of extremely small-sized nanoparticles (<10 nm) like quantum dots (QDs) that are employed as photocatalysts, and in this study, cadmium sulfide (CdS) QDs are chosen. Typically, CdS is an excellent semiconductor with suitable bandgap and band-edge positions that is attractive for applications in solar cells, photocatalysis, and bioimaging. However, the leaching of toxic cadmium (Cd2+) metal ions due to the poor photocorrosion stability of CdS is a matter of serious concern. Therefore, in this report, a cost-effective strategy is devised for biofunctionalizing the active surface of CdS QDs by employing tea leaf extract, which is expected to hinder photocorrosion and prevent the leaching of toxic Cd2+ ions. The coating of tea leaf moieties (chlorophyll and polyphenol) over the CdS QDs (referred to hereafter as G-CdS QDs) was confirmed through structural, morphological, and chemical analysis. Moreover, the enhanced visible-light absorption and emission intensity of G-CdS QDs in comparison to that of C-CdS QDs synthesized through a conventional chemical synthesis approach confirmed the presence of chlorophyll/polyphenol coating. Interestingly, the polyphenol/chlorophyll molecules formed a heterojunction with CdS QDs and enabled the G-CdS QDs to exhibit enhanced photocatalytic activity in the degradation of methylene blue dye molecules over C-CdS QDs while effectively preventing photocorrosion as confirmed from cyclic photodegradation studies. Furthermore, detailed toxicity studies were conducted by exposing zebrafish embryos to the as-synthesized CdS QDs for 72 h. Surprisingly, the survival rate of the zebrafish embryos exposed to G-CdS QDs was equal to that of the control, indicating a significant reduction in the leaching of Cd2+ ions from G-CdS QDs in comparison to C-CdS QDs. The chemical environment of C-CdS and G-CdS before and after the photocatalysis reaction was examined by X-ray photoelectron spectroscopy. These experimental findings prove that biocompatibility and toxicity could be controlled by simply adding tea leaf extract during the synthesis of nanostructured materials, and revisiting green synthesis techniques can be beneficial. Furthermore, repurposing the discarded tea leaves may not only facilitate the control of toxicity of inorganic nanostructured materials but can also help in enhancing global environmental sustainability.

9.
Microb Ecol ; 86(3): 1814-1828, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37133495

RESUMO

Ventilator-associated pneumonia (VAP) is a nosocomial infection contracted by ventilator patients in which bacteria colonize the upper digestive tract and contaminated secretions are released into the lower airway. This nosocomial infection increases the morbidity and mortality of the patients as well as the cost of treatment. Probiotic formulations have recently been proposed to prevent the colonization of these pathogenic bacteria. In this prospective observational study, we aimed to investigate the effects of probiotics on gut microbiota and their relation to clinical outcomes in mechanically ventilated patients. For this study, 35 patients were recruited (22 probiotic-treated and 13 without probiotic treatment) from a cohort of 169 patients. Patients in the probiotic group were given a dose of 6 capsules of a commercially available probiotic (VSL#3®:112.5 billion CFU/cap) in three divided doses for 10 days. Sampling was carried out after each dose to monitor the temporal change in the gut microbiota composition. To profile the microbiota, we used a 16S rRNA metagenomic approach, and differences among the groups were computed using multivariate statistical analyses. Differences in gut microbial diversity (Bray Curtis and Jaccard distance, p-value > 0.05) between the probiotic-treated group and the control group were not observed. Furthermore, treatment with probiotics resulted in the enrichment of Lactobacillus and Streptococcus in the gut microbiota of the probiotic-treated groups. Our results demonstrated that probiotics might lead to favorable alterations in gut microbiome characteristics. Future studies should focus on the appropriate dosages and frequency of probiotics, which can lead to improved clinical outcomes.


Assuntos
Microbioma Gastrointestinal , Probióticos , Humanos , RNA Ribossômico 16S/genética , Probióticos/uso terapêutico , Cuidados Críticos , Progressão da Doença
10.
Gut Pathog ; 15(1): 22, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37161621

RESUMO

BACKGROUND: Severe coronavirus disease 2019 (COVID-19) is associated with systemic hyper-inflammation. An adaptive interaction between gut microbiota and host immune systems is important for intestinal homeostasis and systemic immune regulation. The association of gut microbial composition and functions with COVID-19 disease severity is sparse, especially in India. We analysed faecal microbial diversity and abundances in a cohort of Indian COVID-19 patients to identify key signatures in the gut microbial ecology in patients with severe COVID-19 disease as well as in response to different therapies. The composition of the gut microbiome was characterized using 16Sr RNA gene sequences of genomic DNA extracted from faecal samples of 52 COVID-19 patients. Metabolic pathways across the groups were predicted using PICRUSt2. All statistical analyses were done using Vegan in the R environment. Plasma cytokine abundance at recruitment was measured in a multiplex assay. RESULTS: The gut microbiome composition of mild and severe patients was found to be significantly different. Immunomodulatory commensals, viz. Lachnospiraceae family members and Bifidobacteria producing butyrate and short-chain fatty acids (SCFAs), were under represented in patients with severe COVID-19, with an increased abundance of opportunistic pathogens like Eggerthella. The higher abundance of Lachnoclostridium in severe disease was reduced in response to convalescent plasma therapy. Specific microbial genera showed distinctive trends in enriched metabolic pathways, strong correlations with blood plasma cytokine levels, and associative link to disease outcomes. CONCLUSION: Our study indicates that, along with SARS-CoV-2, a dysbiotic gut microbial community may also play an important role in COVID-19 severity through modulation of host immune responses.

11.
Nanotechnology ; 34(14)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36548988

RESUMO

Plasmonic nanocrystals (NCs) assisted phase transition of two-dimensional molybdenum disulfide (2D-MoS2) unlashes numerous opportunities in the fields of energy harvesting via electrocatalysis and photoelectrocatalysis by enhancing electronic conductivity, increasing catalytic active sites, lowering Gibbs free energy for hydrogen adsorption and desorption, etc. Here, we report the synthesis of faceted gold pentagonal bi-pyramidal (Au-PBP) nanocrystals (NC) for efficient plasmon-induced phase transition (from 2 H to 1 T phase) in chemical vapor deposited 2D-MoS2. The as-developed Au-PBP NC with the increased number of corners and edges showed an enhanced multi-modal plasmonic effect under light irradiations. The overpotential of hydrogen evolution reaction (HER) was reduced by 61 mV, whereas the Tafel slope decreased by 23.7 mV/dec on photoexcitation of the Au-PBP@MoS2hybrid catalyst. The enhanced performance can be attributed to the light-induced 2H to 1 T phase transition of 2D-MoS2, increased active sites, reduced Gibbs free energy, efficient charge separation, change in surface potential, and improved electrical conductivity of 2D-MoS2film. From density functional theory (DFT) calculations, we obtain a significant change in the electronic properties of 2D-MoS2(i.e. work function, surface chemical potential, and the density of states), which was primarily due to the plasmonic interactions and exchange-interactions between the Au-PBP nanocrystals and monolayer 2D-MoS2, thereby enhancing the phase transition and improving the surface properties. This work would lay out finding assorted routes to explore more complex nanocrystals-based multipolar plasmonic NC to escalate the HER activity of 2D-MoS2and other 2D transition metal dichalcogenides.

12.
Sci Rep ; 12(1): 18967, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36347906

RESUMO

The flow through a Hele-Shaw cell is an experimental prototype to study the flow through a porous medium as well as the flow in microfluidic devices. In context with porous medium flows, it is used to visualize and understand hydrodynamic instabilities like viscous fingering (VF). The gap between the plates of the cell is an important parameter affecting the flow dynamics. However, the effect of the gap on the Hele-Shaw cell flows has been minimally explored. We perform experiments to understand the effect of the gap on VF dynamics. It is observed that a minimum gap is required to observe rigorous fingering instability. The onset time of instability, as well as the width of the fingers, increases with an increment in the gap due to a decrease in the convection. The instability increases with an increase in Péclet number, but the effect of gap width on fingering patterns is evident with broader fingers observed for larger b. The results are validated by performing numerical simulations. It is further shown that the gap-averaged three-dimensional simulations using the Stokes law approach and the two-dimensional Darcy's law result in a small gap Hele-Shaw cell.

13.
Phys Rev E ; 106(3-1): 034134, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36266859

RESUMO

We study a p-spin model with ferromagnetic coupling and quenched random crystal fields for p≥3 for spin-1 systems. We find that the model has lines of first-order transitions at finite temperature (T) for all p≥3. For bimodal distribution of the random crystal field these lines meet at a triple point for weak strength of the crystal field (Δ). Beyond a critical strength of Δ, they do not meet and one of the lines ends at a critical point (T_{c}). Interestingly, we find that on increasing T from T_{c}, keeping other parameters fixed, the system undergoes one more transition which is first order in its character. The system thus exhibits a Gardner-like transition for a range of parameters for all finite p≥3. For p→∞ the model behaves differently and there is only one random first-order transition at T=0.

14.
Prog Mol Biol Transl Sci ; 191(1): 53-82, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36270682

RESUMO

Taxonomic composition and functional potency of microbes associated with different parts of the human body have largely been explored by culture-independent metagenome sequencing. The diverse microbiota living throughout the human body is made up of thousands of microbial taxa from all three domains of life: Archaea, Bacteria, and Eukarya. Microbial load and functional potency in different body sites are well distinct and have minimal resemblance at higher taxonomic levels between the two habitats. The highest microbial load, diversity, and functional potency including biosynthesis of essential nutrients, chemical modifications of dietary components, and sources of immunomodulatory molecules, are found in the gut microbiome. However, the inter-individual diversity and dynamics of the human microbiome in a given body habitat vary greatly over time. Both environmental factors and host genetics contribute significantly to shaping microbial community structure and its stability. A basic understanding of native microbial compositions and their functional potency and stability in different parts of healthy humans living across geography will help us to identify disease-specific microbiota and develop potential microbiome-based therapeutics. Here, we updated our current understanding of the diversity, dynamics, and functional potency of microbiomes associated with different parts of the human body.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Bactérias/genética , Metagenoma , Archaea
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 280: 121576, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-35785710

RESUMO

Exploring the potential of non-noble metal substrates for Surface-enhanced Raman spectroscopy (SERS) has attracted considerable interest in recent years. In this work, we prepared nanoplate ß-Bi2O3/Bi2O2CO3 heterostructure via calcination of Bi2O2CO3 precursor using a facile hydrothermal process and successfully demonstrated its use as a novel SERS substrate. The SERS sensitivity of substrate was performed by probing methyl orange (MO), rhodamine B (RhB), vitamin C (Vit. C), and melamine. The observed results show that the SERS signal is enhanced considerably by the adsorption of probe molecules on the surface of the Bismuth heterostructure SERS substrate.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Adsorção , Bismuto , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos
16.
Hum Mutat ; 43(10): 1408-1429, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35762218

RESUMO

Mutation in ATP7B gene causes Wilson disease (WD) that is characterized by severe hepatic and neurological symptoms. ATP7B localizes at the trans-Golgi Network (TGN) transporting copper to copper-dependent enzymes and traffics in apically targeted vesicles upon intracellular copper elevation. To decode the cellular underpinnings of WD manifestation we investigated copper-responsive polarized trafficking and copper transport activity of 15 WD causing point mutations in ATP7B. Amino-terminal mutations Gly85Val, Leu168Pro, and Gly591Asp displayed TGN and subapical localization whereas, Leu492Ser mislocalized at the basolateral region. The actuator domain mutation Gly875Arg shows retention in the endoplasmic reticulum (ER), Ala874Val and Leu795Phe show partial targeting to TGN and post-Golgi vesicles. The nucleotide-binding domain mutations His1069Gln and Leu1083Phe also display impaired targeting. The C-terminal mutations Leu1373Pro/Arg is arrested at ER but Ser1423Asn shows TGN localization. Transmembrane mutant Arg778Leu resides in ER and TGN while Arg969Gln is exclusively ER localized. Cellular Cu level does not alter the targeting of any of the studied mutations. Mutants that traffic to TGN exhibits biosynthetic function. Finally, we correlated cellular phenotypes with the clinical manifestation of the two most prevalent mutations; the early onset and more aggressive WD caused by Arg778Leu and the milder form of WD caused by mutation His1069Gln.


Assuntos
Proteínas de Transporte de Cátions , ATPases Transportadoras de Cobre , Degeneração Hepatolenticular , Adenosina Trifosfatases/química , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , ATPases Transportadoras de Cobre/genética , Estudos de Associação Genética , Degeneração Hepatolenticular/genética , Humanos , Mutação
17.
RSC Adv ; 12(15): 9466-9472, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35424902

RESUMO

Cold atmospheric pressure (CAP) plasma has a profound effect on protein-protein interactions. In this work, we have highlighted the deactivation of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) spike protein by CAP plasma treatment. Complete deactivation of spike protein binding to the human ACE2 protein was observed within an exposure time of 5 minutes which is correlated to the higher concentration of hydrogen peroxide formation due to the interaction with the reactive oxygen species present in the plasma. On the other hand, we have established that CAP plasma is also capable of degrading RNA of SARS-CoV-2 virus which is also linked to hydrogen peroxide concentration. The reactive oxygen species is produced in the plasma by using noble gases such as helium, in the absence of any other chemicals. Therefore, it is a green process with no chemical waste generated and highly advantageous from the environmental safety prospects. Results of this work could be useful in designing plasma-based disinfection systems over those based on environmentally hazardous chemical-based disinfection and biomedical applications.

18.
Microbiol Spectr ; 10(2): e0272921, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35311567

RESUMO

Since its advent, the pandemic has caused havoc in multiple waves due partly to amplified transmissibility and immune escape to vaccines. Delhi, India also witnessed brutal multiple peaks causing exponential rise in cases. Here we had retrospectively investigated clade variation, emergence of new lineages and varied clinical characteristics during those three peaks in order to understand the trajectory of the ongoing pandemic. In this study, a total of 123,378 samples were collected for a time span of 14 months (1 June 2020 to 3 August 2021) encompassing three different peaks in Delhi. A subset of 747 samples was processed for sequencing. Complete clinical and demographic details of all the enrolled cases were also collected. We detected 26 lineages across three peaks nonuniformly from 612 quality passed samples. The first peak was driven by diverse early variants, while the second one by B.1.36 and B.1.617.2, unlike third peak caused entirely by B.1.617.2. A total of 18,316 mutations with median of 34 were reported. Majority of mutations were present in less than 1% of samples. Differences in clinical characteristics across three peaks was also reported. To be ahead of the frequently changing course of the ongoing pandemic, it is of utmost importance that novel lineages be tracked continuously. Prioritized sequencing of sudden local outburst and community hot spots must be done to swiftly detect a novel mutation/lineage of potential clinical importance. IMPORTANCE Genome surveillance of the Delhi data provides a more detailed picture of diverse circulating lineages. The added value that the current study provides by clinical details of the patients is of importance. We looked at the shifting patterns of lineages, clinical characteristics and mutation types and mutation load during each successive infection surge in Delhi. The importance of widespread genomic surveillance cannot be stressed enough to timely detect new variants so that appropriate policies can be immediately implemented upon to help control the infection spread. The entire idea of genomic surveillance is to arm us with the clues as to how the novel mutations and/or variants can prove to be more transmissible and/or fatal. In India, the densely populated cities have an added concern of the huge burden that even the milder variants of the virus combined with co-morbidity can have on the community/primary health care centers.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Genômica , Humanos , Mutação , Filogenia , Estudos Retrospectivos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
19.
Antioxidants (Basel) ; 11(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35204151

RESUMO

Since the hypothesis of Dr. Elie Metchnikoff on lactobacilli-mediated healthy aging, several microbes have been reported to extend the lifespan with different features of healthy aging. However, a microbe affecting diverse features of healthy aging is of choice for broader acceptance and marketability as a next-generation probiotic. We employed Caenorhabditis elegans as a model to understand the potential of Lactobacillus plantarum JBC5 (LPJBC5), isolated from fermented food sample on longevity and healthy aging as well as their underlying mechanisms. Firstly, LPJBC5 enhanced the mean lifespan of C. elegans by 27.81% compared with control (untreated). LPBC5-induced longevity was accompanied with better aging-associated biomarkers, such as physical functions, fat, and lipofuscin accumulation. Lifespan assay on mutant worms and gene expression studies indicated that LPJBC5-mediated longevity was due to upregulation of the skinhead-1 (skn-1) gene activated through p38 MAPK signaling cascade. Secondly, the activated transcription factor SKN-1 upregulated the expression of antioxidative, thermo-tolerant, and anti-pathogenic genes. In support, LPJBC5 conferred resistance against abiotic and biotic stresses such as oxidative, heat, and pathogen. LPJBC5 upregulated the expression of intestinal tight junction protein ZOO-1 and improved gut integrity. Thirdly, LPJBC5 improved the learning and memory of worms trained on LPJBC5 compared with naive worms. The results showed upregulation of genes involved in serotonin signaling (ser-1, mod-1, and tph-1) in LPJBC5-fed worms compared with control, suggesting that serotonin-signaling was essential for LPJBC5-mediated improved cognitive function. Fourthly, LPJBC5 decreased the fat accumulation in worms by reducing the expression of genes encoding key substrates and enzymes of fat metabolism (i.e., fat-5 and fat-7). Lastly, LPJBC5 reduced the production of reactive oxygen species and improved mitochondrial function, thereby reducing apoptosis in worms. The capability of a single bacterium on pro-longevity and the features of healthy aging, including enhancement of gut integrity and cognitive functions, makes it an ideal candidate for promotion as a next-generation probiotic.

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