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Understanding protective immunity to COVID-19 facilitates preparedness for future pandemics and combats new SARS-CoV-2 variants emerging in the human population. Neutralizing antibodies have been widely studied; however, on the basis of large-scale exome sequencing of protected versus severely ill patients with COVID-19, local cell-autonomous defence is also crucial1-4. Here we identify phospholipid scramblase 1 (PLSCR1) as a potent cell-autonomous restriction factor against live SARS-CoV-2 infection in parallel genome-wide CRISPR-Cas9 screens of human lung epithelia and hepatocytes before and after stimulation with interferon-γ (IFNγ). IFNγ-induced PLSCR1 not only restricted SARS-CoV-2 USA-WA1/2020, but was also effective against the Delta B.1.617.2 and Omicron BA.1 lineages. Its robust activity extended to other highly pathogenic coronaviruses, was functionally conserved in bats and mice, and interfered with the uptake of SARS-CoV-2 in both the endocytic and the TMPRSS2-dependent fusion routes. Whole-cell 4Pi single-molecule switching nanoscopy together with bipartite nano-reporter assays found that PLSCR1 directly targeted SARS-CoV-2-containing vesicles to prevent spike-mediated fusion and viral escape. A PLSCR1 C-terminal ß-barrel domain-but not lipid scramblase activity-was essential for this fusogenic blockade. Our mechanistic studies, together with reports that COVID-associated PLSCR1 mutations are found in some susceptible people3,4, identify an anti-coronavirus protein that interferes at a late entry step before viral RNA is released into the host-cell cytosol.
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COVID-19 , Proteínas de Transferência de Fosfolipídeos , SARS-CoV-2 , Animais , Humanos , Camundongos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Quirópteros , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/prevenção & controle , COVID-19/virologia , Sequenciamento do Exoma , Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferon gama/imunologia , Pulmão/imunologia , Pulmão/metabolismo , Fusão de Membrana , Proteínas de Transferência de Fosfolipídeos/química , Proteínas de Transferência de Fosfolipídeos/genética , Proteínas de Transferência de Fosfolipídeos/imunologia , Proteínas de Transferência de Fosfolipídeos/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Internalização do VírusRESUMO
Traditional views of the inflammasome highlight the assembly of pre-existing core components shortly after infection or tissue damage. Emerging work, however, suggests that the inflammasome machinery is also subject to 'tunable' or inducible signals that might accelerate its autocatalytic properties and dictate where inflammasome assembly takes place in the cell. Many of these signals operate downstream of interferon receptors to elicit inflammasome regulators, including a new family of interferon-induced GTPases called 'guanylate-binding proteins' (GBPs). Here we investigate the critical roles of interferon-induced GBPs in directing inflammasome subtype-specific responses and their consequences for cell-autonomous immunity to a wide variety of microbial pathogens. We discuss emerging mechanisms of action and the potential effect of these GBPs on predisposition to sepsis and other infectious or inflammatory diseases.
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Proteínas de Ligação ao GTP/imunologia , Inflamassomos/imunologia , Interferons/imunologia , Transdução de Sinais/imunologia , Animais , Resistência à Doença/genética , Resistência à Doença/imunologia , Proteínas de Ligação ao GTP/classificação , Proteínas de Ligação ao GTP/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Infecções/imunologia , Infecções/microbiologia , Infecções/parasitologia , Inflamassomos/genética , Inflamassomos/metabolismo , Interferons/metabolismo , Listeria monocytogenes/imunologia , Listeria monocytogenes/fisiologia , Camundongos , Modelos Imunológicos , Filogenia , Transdução de Sinais/genética , Toxoplasma/imunologia , Toxoplasma/fisiologiaRESUMO
Liquid-liquid phase separation (LLPS) has emerged as a central paradigm for understanding how membraneless organelles compartmentalize diverse cellular activities in eukaryotes1-3. Here we identify a superfamily of plant guanylate-binding protein (GBP)-like GTPases (GBPLs) that assemble LLPS-driven condensates within the nucleus to protect against infection and autoimmunity. In Arabidopsis thaliana, two members of this family-GBPL1 and GBPL3-undergo phase-transition behaviour to control transcriptional responses as part of an allosteric switch that is triggered by exposure to biotic stress. GBPL1, a pseudo-GTPase, sequesters catalytically active GBPL3 under basal conditions but is displaced by GBPL3 LLPS when it enters the nucleus following immune cues to drive the formation of unique membraneless organelles termed GBPL defence-activated condensates (GDACs) that we visualized by in situ cryo-electron tomography. Within these mesoscale GDAC structures, native GBPL3 directly bound defence-gene promoters and recruited specific transcriptional coactivators of the Mediator complex and RNA polymerase II machinery to massively reprogram host gene expression for disease resistance. Together, our study identifies a GBPL circuit that reinforces the biological importance of phase-separated condensates, in this case, as indispensable players in plant defence.
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Arabidopsis/imunologia , Núcleo Celular/química , Núcleo Celular/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas Intrinsicamente Desordenadas/metabolismo , Transição de Fase , Imunidade Vegetal , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/ultraestrutura , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Cromatina/genética , Microscopia Crioeletrônica , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/ultraestrutura , Regulação da Expressão Gênica de Plantas/genética , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/ultraestrutura , Complexo Mediador , Família Multigênica/genética , Organelas/química , Organelas/imunologia , Organelas/metabolismo , Organelas/ultraestrutura , Células Vegetais/química , Células Vegetais/imunologia , Células Vegetais/metabolismo , Células Vegetais/ultraestrutura , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Regiões Promotoras Genéticas/genética , RNA Polimerase II/metabolismo , Transcrição GênicaRESUMO
Outliers in scientific observations are often ignored and mostly remain unreported. However, presenting them is always beneficial since they could reflect the actual anomalies that might open new avenues. Here, we describe two examples of the above that came out of the laboratories of two of the pioneers of nucleic acid research in the area of protein biosynthesis, Paul Berg and Donald Crothers. Their work on the identification of D-aminoacyl-tRNA deacylase (DTD) and 'Discriminator hypothesis', respectively, were hugely ahead of their time and were partly against the general paradigm at that time. In both of the above works, the smallest and the only achiral amino acid turned out to be an outlier as DTD can act weakly on glycine charged tRNAs with a unique discriminator base of 'Uracil'. This peculiar nature of glycine remained an enigma for nearly half a century. With a load of available information on the subject by the turn of the century, our work on 'chiral proofreading' mechanisms during protein biosynthesis serendipitously led us to revisit these findings. Here, we describe how we uncovered an unexpected connection between them that has implications for evolution of different eukaryotic life forms.
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Aminoaciltransferases , Eucariotos , Glicina , Biossíntese de Proteínas , Aminoácidos/genética , Aminoaciltransferases/genética , Glicina/genética , Aminoacil-RNA de Transferência/metabolismo , Pesquisa , Bioquímica , Eucariotos/química , Eucariotos/genéticaRESUMO
Plants have two endosymbiotic organelles originated from two bacterial ancestors. The transition from an independent bacterium to a successful organelle would have required extensive rewiring of biochemical networks for its integration with archaeal host. Here, using Arabidopsis as a model system, we show that plant D-aminoacyl-tRNA deacylase 1 (DTD1), of bacterial origin, is detrimental to organellar protein synthesis owing to its changed tRNA recognition code. Plants survive this conflict by spatially restricting the conflicted DTD1 to the cytosol. In addition, plants have targeted archaeal DTD2 to both the organelles as it is compatible with their translation machinery due to its strict D-chiral specificity and lack of tRNA determinants. Intriguingly, plants have confined bacterial-derived DTD1 to work in archaeal-derived cytosolic compartment whereas archaeal DTD2 is targeted to bacterial-derived organelles. Overall, the study provides a remarkable example of the criticality of optimization of biochemical networks for survival and evolution of plant mitochondria and chloroplast.
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Arabidopsis , Organelas , Organelas/metabolismo , Mitocôndrias/metabolismo , Aminoacil-RNA de Transferência/metabolismo , Cloroplastos/metabolismo , RNA de Transferência/metabolismo , Arabidopsis/genéticaRESUMO
Hsp90 constitutes one of the major chaperone machinery in the cell. The Hsp70 assists Hsp90 in its client maturation though the underlying basis of the Hsp70 role remains to be explored. In the present study, using S. cerevisiae strain expressing Ssa1 as sole Ssa Hsp70, we identified novel mutations in the nucleotide-binding domain of yeast Ssa1 Hsp70 (Ssa1-T175N and Ssa1-D158N) that adversely affect the maturation of Hsp90 clients v-Src and Ste11. The identified Ssa1 amino acids critical for Hsp90 function were also found to be conserved across species such as in E.coli DnaK and the constitutive Hsp70 isoform (HspA8) in humans. These mutations are distal to the C-terminus of Hsp70, that primarily mediates Hsp90 interaction through the bridge protein Sti1, and proximal to Ydj1 (Hsp40 co-chaperone of Hsp70 family) binding region. Intriguingly, we found that the bridge protein Sti1 is critical for cellular viability in cells expressing Ssa1-T175N (A1-T175N) or Ssa1-D158N (A1-D158N) as sole Ssa Hsp70. The growth defect was specific for sti1Δ, as deletion of none of the other Hsp90 co-chaperones showed lethality in A1-T175N or A1-D158N. Mass-spectrometry based whole proteome analysis of A1-T175N cells lacking Sti1 showed an altered abundance of various kinases and transcription factors suggesting compromised Hsp90 activity. Further proteomic analysis showed that pathways involved in signaling, signal transduction, and protein phosphorylation are markedly downregulated in the A1-T175N upon repressing Sti1 expression using doxycycline regulatable promoter. In contrast to Ssa1, the homologous mutations in Ssa4 (Ssa4-T175N/D158N), the stress inducible Hsp70 isoform, supported cell growth even in the absence of Sti1. Overall, our data suggest that Ydj1 competes with Hsp90 for binding to Hsp70, and thus regulates Hsp90 interaction with the nucleotide-binding domain of Hsp70. The study thus provides new insight into the Hsp70-mediated regulation of Hsp90 and broadens our understanding of the intricate complexities of the Hsp70-Hsp90 network.
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Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteômica , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Chaperonas Moleculares/genética , Nucleotídeos/metabolismo , Ligação Proteica , Adenosina Trifosfatases/metabolismo , MAP Quinase Quinase Quinases/metabolismoRESUMO
BACKGROUND: Climate change exacerbates abiotic stresses, which are expected to intensify their impact on crop plants. Drought, the most prevalent abiotic stress, significantly affects agricultural production worldwide. Improving eggplant varieties to withstand abiotic stress is vital due to rising drought from climate change. Despite the diversity of wild eggplant species that thrive under harsh conditions, the understanding of their drought tolerance mechanisms remains limited. In the present study, we used chlorophyll fluorescence (ChlaF) imaging, which reveals a plant's photosynthetic health, to investigate desiccation tolerance in eggplant and its wild relatives. Conventional fluorescence measurements lack spatial heterogeneity, whereas ChlaF imaging offers comprehensive insights into plant responses to environmental stresses. Hence, employing noninvasive imaging techniques is essential for understanding this heterogeneity. RESULTS: Desiccation significantly reduced the leaf tissue moisture content (TMC) across species. ChlaF and TMC displayed greater photosystem II (PSII) efficiency after 54 h of desiccation in S. macrocarpum, S. torvum, and S. indicum, with S. macrocarpum demonstrating superior efficiency due to sustained fluorescence. PSII functions declined gradually in S. macrocarpum and S. torvum, unlike those in other species, which exhibited abrupt declines after 54 h of desiccation. However, after 54 h, PSII efficiency remained above 50% of its initial quantum yield in S. macrocarpum at 35% leaf RWC (relative water content), while S. torvum and S. indicum displayed 50% decreases at 31% and 33% RWC, respectively. Conversely, the susceptible species S. gilo and S. sisymbriifolium exhibited a 50% reduction in PSII function at an early stage of 50% RWC, whereas in S. melongena, this reduction occurred at 40% RWC. CONCLUSION: Overall, our study revealed notably greater leaf desiccation tolerance, especially in S. macrocarpum, S. torvum, and S. indicum, attributed to sustained PSII efficiency at low TMC levels, indicating that these species are promising sources of drought tolerance.
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Clorofila , Solanum melongena , Clorofila/metabolismo , Fluorescência , Solanum melongena/fisiologia , Solanum melongena/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Dessecação , Complexo de Proteína do Fotossistema II/metabolismo , Fotossíntese/fisiologia , Estresse Fisiológico , Secas , Desidratação , Especificidade da EspécieRESUMO
Fusarium wilt or Panama disease of banana caused by the hemibiotroph fungus, Fusarium odoratissimum, also known as F. oxysporum f.sp. cubense Tropical Race 4 is a serious threat to banana production worldwide. Being the world's largest grower and the origins of bananas in its northeast region, India is particularly vulnerable to this deadly fungus. In the present study, a total of 163 Fusarium isolates from infected banana were characterized for their pathogenic traits. Considering the variability in the Fusarium, the contaminated banana plants were collected from five districts of Uttar Pradesh and Bihar, two major primary infection states of India. All the isolates were screened using universal and specific primers to identify the F. odoratissimum strains. The identified F. odoratissimum strains were subjected to in vivo pathogenicity assessment using the susceptible banana cultivar 'Grand Naine'. The identified six most virulent strains were further characterized for their pathogenicity via in vivo bipartite interaction in terms of biochemical assays. Assessment of in vivo pathogenicity through qRT-PCR for three pathogenesis responsive genes, Six 1a (Secreted in xylem), Snf (Sucrose non-fermenting) and ChsV (Chitinase V), ascertained that the identified F. odoratissimum strains exhibit both intra- and inter-specific variability. The variability of F. odoratissimum strains signifies its importance for the assessment of spread of infection at specific sites to enable efficient management strategy of Fusarium wilt in banana.
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Fusarium , Musa , Doenças das Plantas , Musa/microbiologia , Fusarium/genética , Fusarium/patogenicidade , Fusarium/isolamento & purificação , Fusarium/classificação , Doenças das Plantas/microbiologia , Índia , Virulência/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , FilogeniaRESUMO
BACKGROUND AND AIM: Stroke represents a significant public health challenge, necessitating the exploration of preventive measures. This network meta-analysis aimed to assess the efficacy of different vitamin treatments compared to a placebo in preventing stroke. METHODS: A systematic electronic search in databases including PubMed, EmBASE, Web of Science, clinicaltrials.gov, and Google Scholar until 31 May 2023 was conducted, to identify published studies investigating the association between vitamin intake and the risk of stroke. Pooled risk ratio (RR) with 95% confidence intervals (CIs) was calculated using a frequentist network meta-analysis. Furthermore, we ranked vitamins based on p-scores, facilitating a comparative assessment of their effectiveness in preventing stroke. RESULTS: A total of 56 studies, including 17 randomized controlled trials (RCTs) and 39 cohort studies were analyzed. Direct estimates obtained from network meta-analysis, we found that vitamin A (RR: .81 [.72-.91]), vitamin B-complex (RR: .85 [.74-.97]), vitamin B6 (RR: 79 [.68-.92]), folate (RR: .86 [.75-.97]), vitamin C (RR: .77 [.70-.85]) and vitamin D (RR: .73 [.64-.83]) were significantly associated with a decreased stroke risk. However, no significant association was observed for vitamin B2, vitamin B12, and vitamin E. Subsequent to network meta-analysis, vitamins were ranked in decreasing order of their efficacy in stroke prevention based on p-score, with vitamin D (p-score = .91), vitamin C (p-score = .79), vitamin B6 (p-score = .70), vitamin A (p-score = .65), vitamin B-complex (p-score = .53), folate (p-score = .49), vitamin B2 (p-score = .39), vitamin E (p-score = .28), vitamin B12 (.13) and placebo (.10). CONCLUSION: Our study has established noteworthy connections between vitamin A, vitamin B-complex, vitamin B6, folate, vitamin C, and vitamin D in the realm of stroke prevention. These findings add substantial weight to the accumulating evidence supporting the potential advantages of vitamin interventions in mitigating the risk of stroke. However, to solidify and validate these observations, additional research is imperative. Well-designed clinical trials or cohort studies are needed to further explore these associations and formulate clear guidelines for incorporating vitamin supplementation into effective stroke prevention strategies.
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Ácido Ascórbico , Ácido Fólico , Metanálise em Rede , Acidente Vascular Cerebral , Vitamina A , Vitamina B 6 , Complexo Vitamínico B , Vitamina D , Vitamina E , Vitaminas , Humanos , Vitaminas/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/epidemiologia , Complexo Vitamínico B/uso terapêutico , Ácido Fólico/uso terapêutico , Vitamina D/uso terapêutico , Vitamina E/uso terapêutico , Ácido Ascórbico/uso terapêutico , Vitamina A/uso terapêutico , Vitamina B 6/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Suplementos NutricionaisRESUMO
Natural fibers have garnered considerable attention owing to their desirable textile properties and advantageous effects on human health. Nevertheless, natural fibers lag behind synthetic fibers in terms of both quality and yield, as these attributes are largely genetically determined. In this article, a comprehensive overview of the natural and synthetic fiber production landscape over the last 10 years is presented, with a particular focus on the role of scientific breeding techniques in improving fiber quality traits in key crops like cotton, hemp, ramie, and flax. Additionally, the article delves into cutting-edge genomics-assisted breeding techniques, including QTL mapping, genome-wide association studies, transgenesis, and genome editing, and their potential role in enhancing fiber quality traits in these crops. A user-friendly compendium of 11226 available QTLs and significant marker-trait associations derived from 136 studies, associated with diverse fiber quality traits in these crops is furnished. Furthermore, the potential applications of transcriptomics in these pivotal crops, elucidating the distinct genes implicated in augmenting fiber quality attributes are investigated. Additionally, information on 11257 candidate/characterized or cloned genes sourced from various studies, emphasizing their key role in the development of high-quality fiber crops is collated. Additionally, the review sheds light on the current progress of marker-assisted selection for fiber quality traits in each crop, providing detailed insights into improved cultivars released for different fiber crops. In conclusion, it is asserted that the application of modern breeding tools holds tremendous potential in catalyzing a transformative shift in the textile industry.
Natural fibers possess desirable properties, but they often lag behind synthetic fibers in terms of both quality and quantity. Genomic-assisted breeding has the potential to improve fiber quality traits in cotton, hemp, ramie, and flax. Utilizing available QTLs, marker-trait associations, and candidate genes can contribute to the development of superior fiber crops, underscoring the significance of advanced breeding tools.
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KEY MESSAGE: Multi-environmental characterization of flag leaf morphology traits in the US winter wheat revealed nine stable genomic regions for different flag leaf-related traits including a major region governing flag leaf angle. Flag leaf in wheat is the primary contributor to accumulating photosynthetic assimilates. Flag leaf morphology (FLM) traits determine the overall canopy structure and capacity to intercept the light, thus influencing photosynthetic efficiency. Hence, understanding the genetic control of these traits could be useful for breeding desirable ideotypes in wheat. We used a panel of 272 accessions from the hard winter wheat (HWW) region of the USA to investigate the genetic architecture of five FLM traits including flag leaf length (FLL), width (FLW), angle (FLANG), length-width ratio, and area using multilocation field experiments. Multi-environment GWAS using 14,537 single-nucleotide polymorphisms identified 36 marker-trait associations for different traits, with nine being stable across environments. A novel and major stable region for FLANG (qFLANG.1A) was identified on chromosome 1A accounting for 9-13% variation. Analysis of spatial distribution for qFLANG.1A in a set of 2354 breeding lines from the HWW region showed a higher frequency of allele associated with narrow leaf angle. A KASP assay was developed for allelic discrimination of qFLANG.1A and was used for its independent validation in a diverse set of spring wheat accessions. Furthermore, candidate gene analysis for two regions associated with FLANG identified seven putative genes of interest for each of the two regions. The present study enhances our understanding of the genetic control of FLM in wheat, particularly FLANG, and these results will be useful for dissecting the genes underlying canopy architecture in wheat facilitating the development of climate-resilient wheat varieties.
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Mapeamento Cromossômico , Fenótipo , Melhoramento Vegetal , Folhas de Planta , Polimorfismo de Nucleotídeo Único , Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/anatomia & histologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Locos de Características Quantitativas , Estudos de Associação Genética , Genótipo , Estados Unidos , Genoma de PlantaRESUMO
OH radicals are an important constituent of the atmosphere. Therefore, all reactions that act as a source of OH radicals are important. It is known that photo-dissociation of H2O2 is an important source of OH radicals in the atmosphere. In the present study, using Born-Oppenheimer molecular dynamics simulations, we have shown that the H2O2 molecule can dissociate thermally on water droplets, as well as on the surface of ice, to form OH radicals. Furthermore, the dissociation of H2O2 was found to be very fast (less than 50 fs) on the ice surface compared with on the water droplets. We believe this route for the formation of OH radicals could be more critical than photo-dissociation, as it can take place both during the day and at night, but further studies with more sophisticated theoretical approaches or experiments are required to confirm this hypothesis.
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Alkoxy radicals are key intermediates in the atmospheric degradation of volatile organic compounds. For most alkoxy radicals, reaction with O2 is the primary loss mechanism; however, only α-hydrogen-bearing alkoxy radicals undergo a reaction with O2. Interestingly, if one considers an alkoxy radical that does not possess an α-hydrogen, reaction with O2 is unlikely. In the present work, we propose HO2Ë as a potential reactant for such alkoxy radicals. We have considered the tert-butoxy radical (tBuOË) as a prototype for those alkoxy radicals that do not possess an α-hydrogen. By means of high-level quantum chemical calculations, we have studied the energetics of the tBuOË + HO2Ë reaction along with isomerization and decomposition pathways. Finally, we have discussed the possible atmospheric implications of all three paths in the atmosphere using reaction rate calculations.
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AIMS: We aimed to investigate the prevalence, pathology, and characterization of Streptococcus dysgalactiae subsp. equisimilis (SDSE) in slaughtered pigs of India. METHODS AND RESULTS: We collected 1254 morbid tissues (lungs-627 and spleen-627) and 627 heart-blood from 627 slaughtered pigs. The bacterial isolation, antibiogram, virulence gene profiling, and mouse pathogenicity testing were performed for the detection and characterization of SDSE. A total of 177 isolates (heart-blood-160 and tissues-17) were recovered from 627 slaughtered pigs with higher isolation rate in heart-blood (25.51%). The prevalence of SDSE was 11% in morbid tissues by polymerase chain reaction. Majority of isolates showed higher detection of streptolysin O, followed by streptokinase and extracellular phospholipase A virulence genes with higher degree of resistance to azithromycin, clindamycin, erythromycin, and penicillin antibiotics. Mouse pathogenicity testing confirmed virulence based on histopathological lesions and re-isolation of SDSE. CONCLUSIONS: Our findings highlight the high prevalence of SDSE in slaughtered pigs. The presence of virulence genes and mouse pathogenicity testing confirm their pathogenic potential.
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Antibacterianos , Infecções Estreptocócicas , Streptococcus , Animais , Suínos , Camundongos , Virulência/genética , Antibacterianos/farmacologia , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Farmacorresistência Bacteriana/genéticaRESUMO
In the atmosphere, the photodissociation of HONO is a significant source of OH radicals after ozone. In the present study, using Born-Oppenheimer molecular dynamics, we showed that HONO can dissociate on ice and water surfaces without light. In addition, the dissociation time of HONO is found to be much less on the ice surface compared to the same time on the water droplets.
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The increasing air pollution in the urban atmosphere is adversely impacts the environment, climate and human health. The alarming degradation of air quality, atmospheric conditions, economy and human life due to air pollution needs significant in-depth studies to ascertain causes, contributions and impacts for developing and implementing an effective policy to combat these issues. This work lies in its multifaceted approach towards comprehensive understanding and mitigating severe pollution episodes in Delhi and its surrounding areas. We investigated the aerosol dynamics in the post-monsoon season (PMS) from 2019 to 2022 under the influence of both crop residue burning and meteorological conditions. The study involves a broad spectrum of factors, including PM2.5 concentrations, active fire events, and meteorological parameters, shedding light on previously unexplored studies. The average AOD550 (0.79) and PM2.5 concentration (140.12 µg/m³) were the highest in 2019. PM2.5 was higher from mid-October to mid-November each year, exceeding the WHO guideline of 15 µg/m³ (24 h) by 27-34 times, signifying a public health emergency. A moderate to strong correlation between PM2.5 and AOD was found (r = 0.65) in 2021. The hotspot region accounts for almost 50% (2019), 47.51% (2020), 57.91% (2021) and 36.61% (2022) of the total fire events. A statistically significant negative non-linear correlation (r) was observed between wind speed (WS) and both AOD and PM2.5 concentration, influencing air quality over the region. HYSPLIT model and Windrose result show the movement of air masses predominated from the North and North-West direction during PMS. This study suggest to promotes strategies such as alternative waste management, encouraging modern agricultural practices in hot-spot regions, and enforcing strict emission norms for industries and vehicles to reducing air pollution and its detrimental effects on public health in the region and also highlights the need for future possibilities of research to attract the global attention.
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Aerossóis , Poluentes Atmosféricos , Monitoramento Ambiental , Material Particulado , Índia , Aerossóis/análise , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Estações do Ano , Poluição do Ar/análise , Incêndios , Produtos AgrícolasRESUMO
Pantoea agglomerans inhabit diverse ecological niches, ranging from epiphytes and endophytes in plants, body of animals, and occasionally in the human system. This multifaceted bacterium contributes substantially to plant growth promotion, stress resilience, and biocontrol but can also act as a pathogen to its host. The genetic determinants underlying these diverse functions remain largely unfathomed and to uncover this phenomenon, nineteen strains of Pantoea agglomerans were selected and analyzed. Genome-to-Genome Distance Calculator (GGDC) which uses the Genome Blast Distance Phylogeny (GBDP) technique to calculate digital DDH values. Phylogenetic analysis via Genome-to-Genome distance, Average Nucleotide Identity, and Amino Acid Identity calculation revealed that all strains belonged to the genus Pantoea. However, strain 33.1 had a lower value than the threshold for the same species delineation. Bacterial Pan Genome Analysis (BPGA) Pipeline and MinPath analysis revealed genetic traits associated with environmental resilience, such as oxidative stress, UV radiation, temperature extremes, and metabolism of distinct host-specific carbohydrates. Protein-protein interactome analysis illustrated osmotic stress proteins closely linked with core proteins, while heavy metal tolerance, nitrogen metabolism, and Type III and VI secretion systems proteins generally associated with pathogenicity formed a separate network, indicating strain-specific characteristics. These findings shed new light on the intricate genetic architecture of Pantoea agglomerans, revealing its adaptability to inhabit diverse niches and thrive in varied environments.
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Genoma Bacteriano , Pantoea , Filogenia , Pantoea/genética , Pantoea/fisiologia , Pantoea/classificação , Genômica , Adaptação Fisiológica , Humanos , Animais , Plantas/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismoRESUMO
INTRODUCTION: In an online era like today, the relationship between social media and depression among adolescents and young adults is erratic and still continues to be a debatable subject. The study aims to examine the association and bi-directional relationship between social media usage and depressive symptoms among the adolescent boys and girls in India. METHODS: The study uses data from two waves of Understanding the Lives of Adolescents and Young Adults (UDAYA) project survey conducted in two Indian states of Uttar Pradesh and Bihar. Depression was measured by a Patient Health Questionnaire. Logistic regression has been used for analyzing the data comprising the same time period, whereas the bidirectional relationship between two time periods has been evaluated by Cross-Lagged Path Model. RESULT: Findings suggest that the percentage of moderate depressive symptoms increased from 1.7% to 3.0% from Wave 1 to Wave 2. Depression among adolescent girls increased slightly from wave 1 to wave 2 whereas a slight decrement was noticed in the moderate form of depressive symptom among adolescent girls using social media for the two waves. Socioeconomic factors like education, age, gender played an important role in affecting depression among adolescents in both the Wave of the survey. The path relationship reveals that social media users in Wave 1 [ß=0.22, p<0.001] were positively associated with social media users in Wave 2. Similar patterns were observed for depressive symptoms at both the waves of the survey. However, cross lagged relations between social media use and depression could not be established between the survey periods. CONCLUSION: A significant degree of association was found between social media use and depression among adolescent boys and girls in the study. The present study concludes that factors like age, gender and education showed significant relationships with social media use and depression.
Assuntos
Depressão , Mídias Sociais , Masculino , Feminino , Adulto Jovem , Humanos , Adolescente , Estudos de Coortes , Estudos Longitudinais , Depressão/diagnóstico , Inquéritos e QuestionáriosRESUMO
Natural Products continue to be the purest source of physiologically active molecules employed in the identification of possible lead compounds in the drug discovery process. Acanthaceae is a big plant family with around 2500 species, found primarily in subtropical and tropical regions, as well as the Mediterranean, Australia, and the United States. Several species of the Acanthaceae family have been used traditionally to treat a variety of diseases, including gastrointestinal and cardiovascular ailments, etc. Ruellia tuberosa commonly known as "Mexican Bluebell" is a perennial herb that originated in Central America and has spread to some countries in the Southern tropics and Southeast Asia. It has been utilized as a traditional Rasayana plant from ancient times. R. tuberosa extracts and phytochemicals showed potent bioactivities, such as anticancer, anti-inflammatory, wound healing, antifungal, antimicrobial, anti-diabetic, hypoglycemic, hypolipidemic, gastro-protective, and anthelminthic activities. Chemical analyses have unveiled a range of bioactive constituents within the plant, including alkaloids, flavonoids, saponins, and phenolic compounds, suggestive of its therapeutic potential. Collectively, this review provides an overview of R. tuberosa, encompassing its traditional uses, ethnomedicinal importance, phytochemistry, pharmacological properties, and toxicity.
RESUMO
For early diabetes identification and management, the progression of an uncomplicated and exceedingly responsive glucose testing technology is crucial. In this study, we present a new sensor incorporating a composite of metal organic framework (MOF) based on cobalt, coated with boronic acid to facilitate selective glucose binding. Additionally, we successfully employed a highly sensitive electro-optical immunosensor for the detection of subtle changes in concentration of the diabetes biomarker glycated haemoglobin (HbA1c), using zeolitic imidazolate framework-67 (ZIF-67) coated with polydopamine which further modified with boronic acid. Utilizing the polymerization characteristics of dopamine and the NH2 groups, a bonding structure is formed between ZIF-67 and 4-carboxyphenylboronic acid. ZIF-67 composite served as an effective substrate for immobilising 4-carboxyphenylboronic acid binding agent, ensuring precise and highly selective glucose identification. The sensing response was evaluated through both electrochemical and optical methods, confirming its efficacy. Under optimized experimental condition, the ZIF-67 based sensor demonstrated a broad detection range of 50-500 mg dL-1, a low limit of detection (LOD) of 9.87 mg dL-1 and a high correlation coefficient of 0.98. Furthermore, the 4-carboxyphenylboronic acid-conjugated ZIF-67-based sensor platform exhibited remarkable sensitivity and selectivity in optical-based detection for glycated haemoglobin within the clinical range of 4.7-11.3%, achieving a LOD of 3.7%. These findings highlight the potential of the 4-carboxyphenylboronic acid-conjugated ZIF-67-based electro-optical sensor as a highly sensitive platform for diabetes detection.