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The past two decades has witnessed a remarkable increase in the number of microbial genomes retrieved from marine systems1,2. However, it has remained challenging to translate this marine genomic diversity into biotechnological and biomedical applications3,4. Here we recovered 43,191 bacterial and archaeal genomes from publicly available marine metagenomes, encompassing a wide range of diversity with 138 distinct phyla, redefining the upper limit of marine bacterial genome size and revealing complex trade-offs between the occurrence of CRISPR-Cas systems and antibiotic resistance genes. In silico bioprospecting of these marine genomes led to the discovery of a novel CRISPR-Cas9 system, ten antimicrobial peptides, and three enzymes that degrade polyethylene terephthalate. In vitro experiments confirmed their effectiveness and efficacy. This work provides evidence that global-scale sequencing initiatives advance our understanding of how microbial diversity has evolved in the oceans and is maintained, and demonstrates how such initiatives can be sustainably exploited to advance biotechnology and biomedicine.
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Organismos Aquáticos , Biodiversidade , Bioprospecção , Mapeamento Geográfico , Metagenoma , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Archaea/genética , Archaea/classificação , Bactérias/genética , Bactérias/classificação , Tecnologia Biomédica , Bioprospecção/tendências , Biotecnologia , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/isolamento & purificação , Sistemas CRISPR-Cas/genética , Farmacorresistência Bacteriana/genética , Genoma Arqueal/genética , Genoma Bacteriano/genética , Metagenoma/genética , Oceanos e Mares , Filogenia , Água do Mar/microbiologia , Microbiologia da ÁguaRESUMO
The point spread function (PSF) of a microscope describes the image of a point emitter. Knowing the accurate PSF model is essential for various imaging tasks, including single-molecule localization, aberration correction and deconvolution. Here we present universal inverse modeling of point spread functions (uiPSF), a toolbox to infer accurate PSF models from microscopy data, using either image stacks of fluorescent beads or directly images of blinking fluorophores, the raw data in single-molecule localization microscopy (SMLM). Our modular framework is applicable to a variety of microscope modalities and the PSF model incorporates system- or sample-specific characteristics, for example, the bead size, field- and depth- dependent aberrations, and transformations among channels. We demonstrate its application in single or multiple channels or large field-of-view SMLM systems, 4Pi-SMLM, and lattice light-sheet microscopes using either bead data or single-molecule blinking data.
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Microscopia de Fluorescência , Imagem Individual de Molécula , Imagem Individual de Molécula/métodos , Microscopia de Fluorescência/métodos , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Corantes Fluorescentes/química , Modelos TeóricosRESUMO
The development of single cell RNA sequencing (scRNA-seq) has provided new perspectives to study biological problems at the single cell level. One of the key issues in scRNA-seq data analysis is to divide cells into several clusters for discovering the heterogeneity and diversity of cells. However, the existing scRNA-seq data are high-dimensional, sparse, and noisy, which challenges the existing single-cell clustering methods. In this study, we propose a joint learning framework (JLONMFSC) for clustering scRNA-seq data. In our method, the dimension of the original data is reduced to minimize the effect of noise. In addition, the graph regularized matrix factorization is used to learn the local features. Further, the Low-Rank Representation (LRR) subspace clustering is utilized to learn the global features. Finally, the joint learning of local features and global features is performed to obtain the results of clustering. We compare the proposed algorithm with eight state-of-the-art algorithms for clustering performance on six datasets, and the experimental results demonstrate that the JLONMFSC achieves better performance in all datasets. The code is avalable at https://github.com/lanbiolab/JLONMFSC.
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Perfilação da Expressão Gênica , Análise da Expressão Gênica de Célula Única , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Algoritmos , Análise por ConglomeradosRESUMO
A piezoelectric polymer membrane based on single metal atoms was demonstrated to be effective by anchoring isolated calcium (Ca) atoms on a composite of nitrogen-doped carbon and polyvinylidene fluoride (PVDF). The addition of Ca-atom-anchored carbon nanoparticles not only promotes the formation of the ß phase (from 29.8 to 56.3%), the most piezoelectrically active phase, in PVDF, but also introduces much higher porosity and hydrophilicity. Under ultrasonic excitation, the fabricated catalyst membrane demonstrates a record-high and stable dye decomposing rate of 0.11 min-1 and antibacterial efficiencies of 99.8%. Density functional theory calculations reveal that the primary contribution to catalytic activity arises from single-atom Ca doping and that a possible synergistic effect between PVDF and Ca atoms can improve the catalytic performance. It is shown that O2 molecules can be easily hydrogenated to produce ·OH on Ca-PVDF, and the local electric field provided by the ß-phase-PVDF might enhance the production of ·O2-. The proposed polymer membrane is expected to inspire the rational design of piezocatalysts and pave the way for the application of piezocatalysis technology for practical environmental remediation.
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Although many redox signaling molecules are present at low concentrations, typically ranging from micromolar to submicromolar levels, they often play essential roles in a wide range of biological pathways and disease mechanisms. However, accurately measuring low-abundant analytes has been a significant challenge due to the lack of sensitivity and quantitative capability of existing measurement methods. In this study, we introduced a novel chemically induced amplifiable system for quantifying low-abundance redox signaling molecules in living cells. We utilized H2O2 as a proof-of-concept analyte and developed a probe that quantifies cellular peroxide levels by combining the NanoBiT system with androgen receptor dimerization as a reporting mechanism. Our system demonstrated a highly sensitive response to cellular peroxide changes induced both endogenously and exogenously. Furthermore, the system can be adapted for the quantification of other signaling molecules if provided with suitable probing chemistry.
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Peróxido de Hidrogênio , Receptores Androgênicos , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Humanos , Receptores Androgênicos/metabolismo , OxirreduçãoRESUMO
Most central nervous diseases are accompanied by astrocyte activation. Autophagy, an important pathway for cells to protect themselves and maintain homeostasis, is widely involved in regulation of astrocyte activation. Reactive astrocytes may play a protective or harmful role in different diseases due to different phenotypes of astrocytes. It is an urgent task to clarify the formation mechanisms of inflammatory astrocyte phenotype, A1 astrocytes. Sestrin2 is a highly conserved protein that can be induced under a variety of stress conditions as a potential protective role in oxidative damage process. However, whether Sestrin2 can affect autophagy and involve in A1 astrocyte conversion is still uncovered. In this study, we reported that Sestrin2 and autophagy were significantly induced in mouse hippocampus after multiple intraperitoneal injections of lipopolysaccharide, with the elevation of A1 astrocyte conversion and inflammatory mediators. Knockdown Sestrin2 in C8-D1A astrocytes promoted the levels of A1 astrocyte marker C3 mRNA and inflammatory factors, which was rescued by autophagy inducer rapamycin. Overexpression of Sestrin2 in C8-D1A astrocytes attenuated A1 astrocyte conversion and reduced inflammatory factor levels via abundant autophagy. Moreover, Sestrin2 overexpression improved mitochondrial structure and morphology. These results suggest that Sestrin2 can suppress neuroinflammation by inhibiting A1 astrocyte conversion via autophagy, which is a potential drug target for treating neuroinflammation.
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Astrócitos , Autofagia , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias , Animais , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Camundongos , Masculino , Doenças Neuroinflamatórias/metabolismo , Lipopolissacarídeos/farmacologia , Proteínas Nucleares/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/efeitos dos fármacos , SestrinasRESUMO
Covering: 1993 to the end of 2022As the rapid development of antibiotic resistance shrinks the number of clinically available antibiotics, there is an urgent need for novel options to fill the existing antibiotic pipeline. In recent years, antimicrobial peptides have attracted increased interest due to their impressive broad-spectrum antimicrobial activity and low probability of antibiotic resistance. However, macromolecular antimicrobial peptides of plant and animal origin face obstacles in antibiotic development because of their extremely short elimination half-life and poor chemical stability. Herein, we focus on medium-sized antibacterial peptides (MAPs) of microbial origin with molecular weights below 2000 Da. The low molecular weight is not sufficient to form complex protein conformations and is also associated to a better chemical stability and easier modifications. Microbially-produced peptides are often composed of a variety of non-protein amino acids and terminal modifications, which contribute to improving the elimination half-life of compounds. Therefore, MAPs have great potential for drug discovery and are likely to become key players in the development of next-generation antibiotics. In this review, we provide a detailed exploration of the modes of action demonstrated by 45 MAPs and offer a concise summary of the structure-activity relationships observed in these MAPs.
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Antibacterianos , Peptídeos Antimicrobianos , Antibacterianos/farmacologia , Antibacterianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Relação Estrutura-Atividade , Desenvolvimento de MedicamentosRESUMO
The current limitations of single-molecule localization microscopy (SMLM) in deep tissue imaging, primarily due to depth-dependent aberrations caused by refractive index (RI) mismatch, present a significant challenge in achieving high-resolution images at greater depths. To extend the imaging depth, we optimized the imaging buffer of SMLM with the RI matched to that of the objective immersion medium and systematically evaluated five different RI-matched buffers, focusing on their impact on the blinking behavior of red-absorbing dyes and the quality of reconstructed super-resolution images. Particularly, we found that clear unobstructed brain imaging cocktails-based imaging buffer could match the RI of oil and was able to clear the tissue samples. With the help of the RI-matched imaging buffers, we showed high-quality dual-color 3D SMLM images with imaging depths ranging from a few micrometers to tens of micrometers in both cultured cells and sectioned tissue samples. This advancement offers a practical and accessible method for high-resolution imaging at greater depths without the need for specialized optical equipment or expertise.
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Encéfalo , Refratometria , Animais , Encéfalo/diagnóstico por imagem , Imagem Individual de Molécula/métodos , Imageamento Tridimensional , Humanos , Cor , Camundongos , Soluções Tampão , Corantes Fluorescentes/químicaRESUMO
Fungi generate a diverse array of bioactive compounds with significant pharmaceutical applications. However, the chemical diversity of natural products in fungi remains largely unexplored. Here, we present a paradigm for specifically discovering diverse and bioactive compounds from fungi by integrating genome mining with building block molecular network and coculture analysis. Through pangenome and sequence similarity network analysis, we identified a rare type I polyketide enzyme from Penicillium sp. ZJUT-34. Subsequent building block molecular network and coculture strategy led to the identification and isolation of a pair of novel polyketides, (±)-peniphenone E [(±)-1], three known polyketides (2-4), and three precursor compounds (5-7) from a combined culture of Penicillium sp. ZJUT-34 and Penicillium sp. ZJUT23. Their structures were established through extensive spectroscopic analysis, including NMR and HRESIMS. Chiral HPLC separation of compound 1 yielded a pair of enantiomers (+)-1 and (-)-1, with their absolute configurations determined using calculated ECD methods. Compound (±)-1 is notable for its unprecedented structure, featuring a unique 2-methyl-hexenyl-3-one moiety fused with a polyketide clavatol core. We proposed a hypothetical biosynthetic pathway for (±)-1. Furthermore, compounds 2, 5, and 6 exhibited strong antioxidant activity, whereas (-)-1, (+)-1, 3, and four exhibited moderate antioxidant activity compared to the positive control, ascorbic acid. Our research demonstrates a pioneering strategy for uncovering novel polyketides by merging genome mining, metabolomics, and cocultivation methods. This approach addresses the challenge of discovering natural compounds produced by rare biosynthetic enzymes that are often silent under conventional conditions due to gene regulation.IMPORTANCEPolyketides, particularly those with complex structures, are crucial in drug development and synthesis. This study introduces a novel approach to discover new polyketides by integrating genomics, metabolomics, and cocultivation strategies. By combining genome mining, building block molecular networks, and coculturing techniques, we identified and isolated a unique polyketide, (±)-peniphenone E, along with three known polyketides and three precursor compounds from Penicillium sp. ZJUT-34 and Penicillium sp. ZJUT23. This approach highlights the potential of using combined strategies to explore fungal chemical diversity and discover novel bioactive compounds. The successful identification of (±)-peniphenone E, with its distinctive structure, demonstrates the effectiveness of this integrated method in enhancing natural product discovery and underscores the value of innovative approaches in natural product research.
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INTRODUCTION: The connection between periodontitis and mild cognitive impairment (MCI) continues to receive attention. However, whether periodontitis is a risk factor for MCI remains still uncertain. This study aims to systematically analyze the available literature regarding the relationship between periodontitis and the risk of developing MCI and whether the periodontal health of MCI patients is poorer. METHODS: A literature search of PubMed, Scopus, Embase, and Web of Science databases was conducted to include all studies on the relationship between periodontitis and MCI from inception to April 2023. The studies were independently screened by 2 researchers, and those meeting the inclusion criteria were extracted and cross-checked. Pooled odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CI) was calculated using either a fixed-effects or random-effects model. RESULTS: Seven studies with a total of 3,973 participants were included. Meta-analysis results showed a statistically significant higher incidence of MCI in patients with periodontitis (OR, 1.70 (95% CI: 1.24-2.32, p < 0.001) compared to healthy participants. A subgroup meta-analysis showed that the pooled OR for the risk of MCI in patients with severe periodontitis was 2.09 (95% CI: 1.49-2.92, p < 0.001). In addition, attachment loss (MD = 0.44, 95% CI: 0.12-0.75, p < 0.001) and plaque index (MD = 0.72, 95% CI: 0.50-0.93, p < 0.001) were higher in MCI patients compared with the control group, but the pocket probing depth (MD = 0.21, 95% CI: -0.08 to 0.49, p = 0.15) was not significantly different between the two groups. CONCLUSIONS: Patients with periodontitis are at a higher risk of developing MCI, and the periodontal health of MCI patients is generally compromised. However, further well-designed studies should be conducted to confirm this relationship between MCI and periodontitis.
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Disfunção Cognitiva , Periodontite , Humanos , Disfunção Cognitiva/epidemiologia , Periodontite/epidemiologia , Periodontite/complicações , Fatores de RiscoRESUMO
Candida auris is a widely distributed, highly lethal, multidrug-resistant fungal pathogen. It was first identified in 2009 when it was isolated from fluid drained from the external ear canal of a patient in Japan. Since then, it has caused infectious outbreaks in over 45 countries, with mortality rates approaching 60%. Drug resistance is common in this species, with a large proportion of isolates displaying fluconazole resistance and nearly half are resistant to two or more antifungal drugs. In this review, we describe the drug resistance mechanism of C. auris and potential small-molecule drugs for treating C. auris infection. Among these antifungal agents, rezafungin was approved by the US Food and Drug Administration (FDA) for the treatment of candidemia and invasive candidiasis on March 22, 2023. Ibrexafungerp and fosmanogepix have entered phase III clinical trials.
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Candida auris , Candidíase Invasiva , Humanos , Candida , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fungos , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/veterinária , Testes de Sensibilidade Microbiana/veterináriaRESUMO
BACKGROUND: The Pearl River and its estuary are highly exposed to anthropogenic disturbance. Because bacterial communities play an indispensable role in aquatic ecosystems, there has been an increased research focus on the statuses of these communities under human-induced perturbations. METHODS AND RESULTS: This study investigated the composition, diversity, and structure of bacterial communities across 29 sites from the Guangzhou section of the Pearl River (GZ) to the Pearl River Estuary (PRE) using 16S rRNA gene amplicons. The results revealed similar dominant phyla of bacteria in both GZ and PRE, as well as significant differences in bacterial community composition and diversity between the two sections. Proteobacteria and Cyanobacteria were identified as the primary drivers of compositional differences between GZ and PRE. The Cyanobacteria Dolichospermum_NIES41 and Cuspidothrix issatschenkoi were only present in GZ, whereas the marine Gram-negative bacteria of Porticoccus litoralis and Thalassolituus oleivorans were unique to PRE. CONCLUSIONS: Bacterial community composition and diversity exhibit both similarities and differences between GZ and PRE; Proteobacteria and Cyanobacteria are key factors underlying these variations. Bacterial communities in both GZ and PRE are strongly influenced by human activities, and salinity is an important factor in controlling their differences. This study provides a comprehensive analysis of the bacterial communities in GZ and PRE, establishing a foundation for better management of aquatic ecosystems impacted by anthropogenic activities.
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Bactérias , Cianobactérias , Estuários , RNA Ribossômico 16S , Rios , Rios/microbiologia , RNA Ribossômico 16S/genética , China , Bactérias/genética , Bactérias/classificação , Cianobactérias/genética , Cianobactérias/isolamento & purificação , Cianobactérias/classificação , Filogenia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Biodiversidade , Ecossistema , Microbiologia da Água , DNA Bacteriano/genética , Microbiota/genéticaRESUMO
BACKGROUND: Traumatic fractures occur frequently worldwide. However, research remains limited on the association between short-term exposure to temperature and traumatic fractures. This study aims to explore the impact of apparent temperature (AT) on emergency visits (EVs) due to traumatic fractures. METHODS: Based on EVs data for traumatic fractures and the contemporary meteorological data, a generalized Poisson regression model along with a distributed lag nonlinear model (DLNM) were undertaken to determine the impact of AT on traumatic fracture EVs. Subgroup analysis by gender and age and sensitivity analysis were also performed. RESULTS: A total of 25,094 EVs for traumatic fractures were included in the study. We observed a wide "J"-shaped relationship between AT and risk of traumatic fractures, with AT above 9.5 °C positively associated with EVs due to traumatic fractures. The heat effects became significant at cumulative lag 0-11 days, and the relative risk (RR) for moderate heat (95th percentile, 35.7 °C) and extreme heat (99.5th percentile, 38.8 °C) effect was 1.311 (95% CI: 1.132-1.518) and 1.418 (95% CI: 1.191-1.688) at cumulative lag 0-14 days, respectively. The cold effects were consistently non-significant on single or cumulative lag days across 0-14 days. The heat effects were higher among male and those aged 18-65 years old. The sensitivity analysis results remained robust. CONCLUSION: Higher AT is associated with cumulative and delayed higher traumatic fracture EVs. The male and those aged 18-65 years are more susceptible to higher AT.
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Serviço Hospitalar de Emergência , Fraturas Ósseas , Humanos , Masculino , Feminino , Adulto , China/epidemiologia , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Fraturas Ósseas/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Idoso , Criança , Pré-Escolar , Temperatura , Lactente , Temperatura Alta/efeitos adversosRESUMO
The actinomycete genus Rhodococcus is known for its diverse biosynthetic enzymes, with potential in pollutant degradation, chemical biocatalysis, and natural product exploration. Comparative genomics have analyzed the distribution patterns of non-ribosomal peptide synthetases (NRPSs) in Rhodococcus. The diversity and specificity of its secondary metabolism offer valuable insights for exploring natural products, yet remain understudied. In the present study, we analyzed the distribution patterns of biosynthetic gene clusters (BGCs) in the most comprehensive Rhodococcus genome data to date. The results show that 86.5% of the gene cluster families (GCFs) are only distributed in a specific phylogenomic-clade of Rhodococcus, with the most predominant types of gene clusters being NRPS and ribosomally synthesized and post-translationally modified peptides (RiPPs). In-depth mining of RiPP gene clusters revealed that Rhodococcus encodes many clade-specific novel RiPPs, with thirteen core peptides showing antibacterial potential. High-throughput elicitor screening (HiTES) and non-targeted metabolomics revealed that a marine-derived Rhodococcus strain produces a large number of new aurachin-like compounds when exposed to specific elicitors. The present study highlights the diversity and specificity of secondary biosynthetic potential in Rhodococcus, and provides valuable information for the targeted exploration of novel natural products from Rhodococcus, especially for phylogenomic-clade-specific metabolites.
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Produtos Biológicos , Família Multigênica , Filogenia , Rhodococcus , Metabolismo Secundário , Rhodococcus/genética , Rhodococcus/metabolismo , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Genoma Bacteriano , Antibacterianos/farmacologia , Antibacterianos/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismoRESUMO
Permafrost degradation may induce soil carbon (C) loss, critical for global C cycling, and be mediated by microbes. Despite larger C stored within the active layer of permafrost regions, which are more affected by warming, and the critical roles of Qinghai-Tibet Plateau in C cycling, most previous studies focused on the permafrost layer and in high-latitude areas. We demonstrate in situ that permafrost degradation alters the diversity and potentially decreases the stability of active layer microbial communities. These changes are associated with soil C loss and potentially a positive C feedback. This study provides insights into microbial-mediated mechanisms responsible for C loss within the active layer in degraded permafrost, aiding in the modeling of C emission under future scenarios.
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Carbono/análise , Microbiologia Ambiental , Pergelissolo , Biodiversidade , China , Microbiota , Compostos Orgânicos/análise , Plantas , Solo/químicaRESUMO
BACKGROUND: Bivalves have independently evolved a variety of symbiotic relationships with chemosynthetic bacteria. These relationships range from endo- to extracellular interactions, making them ideal for studies on symbiosis-related evolution. It is still unclear whether there are universal patterns to symbiosis across bivalves. Here, we investigate the hologenome of an extracellular symbiotic thyasirid clam that represents the early stages of symbiosis evolution. RESULTS: We present a hologenome of Conchocele bisecta (Bivalvia: Thyasiridae) collected from deep-sea hydrothermal vents with extracellular symbionts, along with related ultrastructural evidence and expression data. Based on ultrastructural and sequencing evidence, only one dominant Thioglobaceae bacteria was densely aggregated in the large bacterial chambers of C. bisecta, and the bacterial genome shows nutritional complementarity and immune interactions with the host. Overall, gene family expansions may contribute to the symbiosis-related phenotypic variations in different bivalves. For instance, convergent expansions of gaseous substrate transport families in the endosymbiotic bivalves are absent in C. bisecta. Compared to endosymbiotic relatives, the thyasirid genome exhibits large-scale expansion in phagocytosis, which may facilitate symbiont digestion and account for extracellular symbiotic phenotypes. We also reveal that distinct immune system evolution, including expansion in lipopolysaccharide scavenging and contraction of IAP (inhibitor of apoptosis protein), may contribute to the different manners of bacterial virulence resistance in C. bisecta. CONCLUSIONS: Thus, bivalves employ different pathways to adapt to the long-term co-existence with their bacterial symbionts, further highlighting the contribution of stochastic evolution to the independent gain of a symbiotic lifestyle in the lineage.
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Bivalves , Animais , Bivalves/genética , Transporte Biológico , Genoma Bacteriano , Proteínas Inibidoras de Apoptose , LipopolissacarídeosRESUMO
Moso bamboo (Phyllostachys edulis) is a valuable nontimber forestry product with a biennial cycle, producing abundant bamboo shoots within one year (on-year) and few shoots within the following year (off-year). Moso bamboo plants undergo clonal reproduction, resulting in similar genetic backgrounds. However, the number of moso bamboo shoots produced each year varies. Despite this variation, the impact of soil nutrients and the root microbiome on the biennial bearing of moso bamboo is poorly understood. We collected 139 soil samples and determined 14 major physicochemical properties of the rhizosphere, rhizoplane, and bulk soil in different seasons (i.e., the growing and deciduous seasons) and different years (i.e., on- and off-years). Based on 16S rRNA and metagenomic sequencing, major variations were found in the rhizospheric microbial composition during different seasons and years in the moso bamboo forest. Environmental driver analysis revealed that essential nutrients (i.e., SOC, TOC, TN, P, and NH4+) were the main drivers of the soil microbial community composition and were correlated with the on- and off-year cycles. Moreover, 19 MAGs were identified as important biomarkers that could distinguish on- and off-years. We found that both season and year influenced both the microbial community structure and functional pathways through the biosynthesis of nutrients that potentially interact with the moso bamboo growth rhythm, especially the on-year root-associated microbiome, which had a greater abundance of specific nutrients such as gibberellins and vitamin B6. This work provides a dynamic perspective of the differential responses of various on- and off-year microbial communities and enhances our understanding of bamboo soil microbiome biodiversity and stability.
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Poaceae , Rizosfera , RNA Ribossômico 16S/genética , Florestas , Solo/químicaRESUMO
Bacterial virulence factors and biofilm development can be controlled by the quorum-sensing (QS) system, which is also intimately linked to antibiotic resistance in bacteria. In previous studies, many researchers found that quorum-sensing inhibitors (QSIs) can affect the development of bacterial biofilms and prevent the synthesis of many virulence factors. However, QSIs alone have a limited ability to suppress bacteria. Fortunately, when QSIs are combined with antibiotics, they have a better therapeutic effect, and it has even been demonstrated that the two together have a synergistic antibacterial effect, which not only ensures bactericidal efficiency but also avoids the resistance caused by excessive use of antibiotics. In addition, some progress has been made through in vivo studies on the combination of QSIs and antibiotics. This article mainly expounds on the specific effect of QSIs combined with antibiotics on bacteria and the combined antibacterial mechanism of some QSIs and antibiotics. These studies will provide new strategies and means for the clinical treatment of bacterial infections in the future.
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Antibacterianos , Infecções Bacterianas , Humanos , Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Percepção de Quorum , Biofilmes , Fatores de VirulênciaRESUMO
Wastewater-based SARS-CoV-2 surveillance enables unbiased and comprehensive monitoring of defined sewersheds. We performed real-time monitoring of hospital wastewater that differentiated Delta and Omicron variants within total SARS-CoV-2-RNA, enabling correlation to COVID-19 cases from three tertiary-care facilities with >2100 inpatient beds in Calgary, Canada. RNA was extracted from hospital wastewater between August/2021 and January/2022, and SARS-CoV-2 quantified using RT-qPCR. Assays targeting R203M and R203K/G204R established the proportional abundance of Delta and Omicron, respectively. Total and variant-specific SARS-CoV-2 in wastewater was compared to data for variant specific COVID-19 hospitalizations, hospital-acquired infections, and outbreaks. Ninety-six percent (188/196) of wastewater samples were SARS-CoV-2 positive. Total SARS-CoV-2 RNA levels in wastewater increased in tandem with total prevalent cases (Delta plus Omicron). Variant-specific assessments showed this increase to be mainly driven by Omicron. Hospital-acquired cases of COVID-19 were associated with large spikes in wastewater SARS-CoV-2 and levels were significantly increased during outbreaks relative to nonoutbreak periods for total SARS-CoV2, Delta and Omicron. SARS-CoV-2 in hospital wastewater was significantly higher during the Omicron-wave irrespective of outbreaks. Wastewater-based monitoring of SARS-CoV-2 and its variants represents a novel tool for passive COVID-19 infection surveillance, case identification, containment, and potentially to mitigate viral spread in hospitals.
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COVID-19 , SARS-CoV-2 , Humanos , RNA Viral , Águas Residuárias , Centros de Atenção Terciária , Surtos de DoençasRESUMO
Antipsychotic agents are clinically utilized to treat schizophrenia and other mental disorders. These drugs induce neurological and metabolic side effects, but their influence on blood vessels remains largely unknown. Here, we show that haloperidol, one of the most frequently prescribed antipsychotic agents, induces vascular defects in bone marrow. Acute haloperidol treatment results in vascular dilation that is specific to hematopoietic organs. This vessel dilation is associated with disruption of hematopoiesis and hematopoietic stem/progenitor cells (HSPCs), both of which are reversible after haloperidol withdrawal. Mechanistically, haloperidol treatment blocked the secretion of vascular endothelial growth factor A (VEGF-A) from HSPCs. Genetic blockade of VEGF-A secretion from hematopoietic cells or inhibition of VEGFR2 in endothelial cells result in similar vessel dilation in bone marrow during regeneration after irradiation and transplantation. Conversely, VEGF-A gain of function rescues the bone marrow vascular defects induced by haloperidol treatment and irradiation. Our work reveals an unknown effect of antipsychotic agents on the vasculature and hematopoiesis with potential implications for drug application in clinic.