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1.
Glob Chang Biol ; 30(4): e17268, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38562029

RESUMO

Although substantial advances in predicting the ecological impacts of global change have been made, predictions of the evolutionary impacts have lagged behind. In soil ecosystems, microbes act as the primary energetic drivers of carbon cycling; however, microbes are also capable of evolving on timescales comparable to rates of global change. Given the importance of soil ecosystems in global carbon cycling, we assess the potential impact of microbial evolution on carbon-climate feedbacks in this system. We begin by reviewing the current state of knowledge concerning microbial evolution in response to global change and its specific effect on soil carbon dynamics. Through this integration, we synthesize a roadmap detailing how to integrate microbial evolution into ecosystem biogeochemical models. Specifically, we highlight the importance of microscale mechanistic soil carbon models, including choosing an appropriate evolutionary model (e.g., adaptive dynamics, quantitative genetics), validating model predictions with 'omics' and experimental data, scaling microbial adaptations to ecosystem level processes, and validating with ecosystem-scale measurements. The proposed steps will require significant investment of scientific resources and might require 10-20 years to be fully implemented. However, through the application of multi-scale integrated approaches, we will advance the integration of microbial evolution into predictive understanding of ecosystems, providing clarity on its role and impact within the broader context of environmental change.


Assuntos
Ecossistema , Microbiologia do Solo , Solo , Carbono , Clima
2.
J Nat Prod ; 87(2): 439-452, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38353658

RESUMO

Marine-derived Streptomyces have long been recognized as a source of novel, pharmaceutically relevant natural products. Among these bacteria, the MAR4 clade within the genus Streptomyces has been identified as metabolically rich, yielding over 93 different compounds to date. MAR4 strains are particularly noteworthy for the production of halogenated hybrid isoprenoid natural products, a relatively rare class of bacterial metabolites that possess a wide range of biological activities. MAR4 genomes are enriched in vanadium haloperoxidase and prenyltransferase genes, thus accounting for the production of these compounds. Functional characterization of the enzymes encoded in MAR4 genomes has advanced our understanding of halogenated, hybrid isoprenoid biosynthesis. Despite the exceptional biosynthetic capabilities of MAR4 bacteria, the large body of research they have stimulated has yet to be compiled. Here we review 35 years of natural product research on MAR4 strains and update the molecular diversity of this unique group of bacteria.


Assuntos
Produtos Biológicos , Streptomyces , Streptomyces/genética , Streptomyces/metabolismo , Produtos Biológicos/metabolismo , Terpenos/metabolismo , Família Multigênica
3.
Proc Natl Acad Sci U S A ; 118(18)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33906949

RESUMO

Microbial community responses to environmental change are largely associated with ecological processes; however, the potential for microbes to rapidly evolve and adapt remains relatively unexplored in natural environments. To assess how ecological and evolutionary processes simultaneously alter the genetic diversity of a microbiome, we conducted two concurrent experiments in the leaf litter layer of soil over 18 mo across a climate gradient in Southern California. In the first experiment, we reciprocally transplanted microbial communities from five sites to test whether ecological shifts in ecotypes of the abundant bacterium, Curtobacterium, corresponded to past adaptive differentiation. In the transplanted communities, ecotypes converged toward that of the native communities growing on a common litter substrate. Moreover, these shifts were correlated with community-weighted mean trait values of the Curtobacterium ecotypes, indicating that some of the trait variation among ecotypes could be explained by local adaptation to climate conditions. In the second experiment, we transplanted an isogenic Curtobacterium strain and tracked genomic mutations associated with the sites across the same climate gradient. Using a combination of genomic and metagenomic approaches, we identified a variety of nonrandom, parallel mutations associated with transplantation, including mutations in genes related to nutrient acquisition, stress response, and exopolysaccharide production. Together, the field experiments demonstrate how both demographic shifts of previously adapted ecotypes and contemporary evolution can alter the diversity of a soil microbiome on the same timescale.


Assuntos
Actinobacteria/genética , Adaptação Fisiológica/genética , Mudança Climática , Microbiota/genética , Actinobacteria/classificação , Actinobacteria/crescimento & desenvolvimento , California , Ecótipo , Variação Genética/genética , Metagenoma/genética , RNA Ribossômico 16S/genética , Microbiologia do Solo
4.
Ecol Lett ; 26 Suppl 1: S81-S90, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36965002

RESUMO

Microorganisms are the primary engines of biogeochemical processes and foundational to the provisioning of ecosystem services to human society. Free-living microbial communities (microbiomes) and their functioning are now known to be highly sensitive to environmental change. Given microorganisms' capacity for rapid evolution, evolutionary processes could play a role in this response. Currently, however, few models of biogeochemical processes explicitly consider how microbial evolution will affect biogeochemical responses to environmental change. Here, we propose a conceptual framework for explicitly integrating evolution into microbiome-functioning relationships. We consider how microbiomes respond simultaneously to environmental change via four interrelated processes that affect overall microbiome functioning (physiological acclimation, demography, dispersal and evolution). Recent evidence in both the laboratory and the field suggests that ecological and evolutionary dynamics occur simultaneously within microbiomes; however, the implications for biogeochemistry under environmental change will depend on the timescales over which these processes contribute to a microbiome's response. Over the long term, evolution may play an increasingly important role for microbially driven biogeochemical responses to environmental change, particularly to conditions without recent historical precedent.

5.
J Sex Med ; 20(5): 605-611, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36897060

RESUMO

BACKGROUND: Previous cross-sectional and longitudinal studies have described decreasing testosterone levels with age in men, without consideration of acquired comorbidities in aging males. AIM: We evaluated the longitudinal association between age and testosterone levels as well as the impact of several comorbidities on this relationship using multivariate panel regression analysis. METHODS: Participants were selected from the Baltimore Longitudinal Study of Aging. Data were obtained on the presence of several comorbidities and total testosterone level during each follow-up visit. A multivariate panel regression analysis was performed to determine the impact of age on testosterone level while controlling for individual comorbidities. OUTCOMES: The primary outcomes were strength of association between age and various comorbidities, and testosterone level. RESULTS: A total of 625 men were included in this study, with a mean age of 65 years and a mean testosterone level of 463 ng/dL. On multivariable-adjusted panel regression analysis, age was not significantly associated with testosterone decline, while anemia, diabetes mellitus, heart failure, obesity, peripheral artery disease, and stroke were inversely associated with total testosterone level. We report no association between cancer and total testosterone. CLINICAL IMPLICATIONS: This study indicates that a decline in testosterone levels over time may be due to the presence of various comorbidities, which affects the medical management of hypogonadism in aging men. STRENGTHS AND LIMITATIONS: The strengths of this study include the standardized acquisition of testosterone tests and uniform collection of variables, while limitations include the lack of follow-up data from 205 patients and the limited racial/ethnic diversity in the cohort. CONCLUSIONS: In this large longitudinal study, we found that when adjusted for the presence of concomitant comorbidities, age does not predict a significant decline in testosterone level. With the overall increase in life expectancy and the simultaneous rise in the incidence of comorbidities such as diabetes and dyslipidemia, our findings may help optimize screening and treatment for late-onset hypogonadism in patients with multiple comorbidities.


Assuntos
Hipogonadismo , Testosterona , Masculino , Humanos , Idoso , Testosterona/uso terapêutico , Estudos Longitudinais , Baltimore/epidemiologia , Estudos Transversais , Envelhecimento , Hipogonadismo/epidemiologia , Hipogonadismo/tratamento farmacológico
6.
Catheter Cardiovasc Interv ; 99(2): 305-313, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33942478

RESUMO

OBJECTIVES: To describe outcomes following percutaneous coronary intervention (PCI) in patients who would usually have undergone coronary artery bypass grafting (CABG). BACKGROUND: In the United Kingdom, cardiac surgery for coronary artery disease (CAD) was dramatically reduced during the first wave of the COVID-19 pandemic. Many patients with "surgical disease" instead underwent PCI. METHODS: Between 1 March 2020 and 31 July 2020, 215 patients with recognized "surgical" CAD who underwent PCI were enrolled in the prospective UK-ReVasc Registry (ReVR). 30-day major cardiovascular event outcomes were collected. Findings in ReVR patients were directly compared to reference PCI and isolated CABG pre-COVID-19 data from British Cardiovascular Intervention Society (BCIS) and National Cardiac Audit Programme (NCAP) databases. RESULTS: ReVR patients had higher incidence of diabetes (34.4% vs 26.4%, P = .008), multi-vessel disease with left main stem disease (51.4% vs 3.0%, P < .001) and left anterior descending artery involvement (94.8% vs 67.2%, P < .001) compared to BCIS data. SYNTAX Score in ReVR was high (mean 28.0). Increased use of transradial access (93.3% vs 88.6%, P = .03), intracoronary imaging (43.6% vs 14.4%, P < .001) and calcium modification (23.6% vs 3.5%, P < .001) was observed. No difference in in-hospital mortality was demonstrated compared to PCI and CABG data (ReVR 1.4% vs BCIS 0.7%, P = .19; vs NCAP 1.0%, P = .48). Inpatient stay was half compared to CABG (3.0 vs 6.0 days). Low-event rates in ReVR were maintained to 30-day follow-up. CONCLUSIONS: PCI undertaken using contemporary techniques produces excellent short-term results in patients who would be otherwise CABG candidates. Longer-term follow-up is essential to determine whether these outcomes are maintained over time.


Assuntos
COVID-19 , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Ponte de Artéria Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Hirudinas , Humanos , Pandemias , Estudos Prospectivos , Proteínas Recombinantes , Sistema de Registros , SARS-CoV-2 , Resultado do Tratamento
7.
J Nat Prod ; 85(4): 980-986, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35263117

RESUMO

A new manumycin-type natural product named pacificamide (1) and its candidate biosynthetic gene cluster (pac) were discovered from the marine actinobacterium Salinispora pacifica CNT-855. The structure of the compound was determined using NMR, electronic circular dichroism, and bioinformatic predictions. The pac gene cluster is unique to S. pacifica and found in only two of the 119 Salinispora genomes analyzed across nine species. Comparative analyses of biosynthetic gene clusters encoding the production of related manumycin-type compounds revealed genetic differences in accordance with the unique pacificamide structure. Further queries of manumycin-type gene clusters from public databases revealed their limited distribution across the phylum Actinobacteria and orphan diversity that suggests additional products remain to be discovered in this compound class. Production of the known metabolite triacsin D is also reported for the first time from the genus Salinispora. This study adds two classes of compounds to the natural product collective isolated from the genus Salinispora, which has proven to be a useful model for natural product research.


Assuntos
Produtos Biológicos , Micromonosporaceae , Produtos Biológicos/metabolismo , Micromonosporaceae/genética , Micromonosporaceae/metabolismo , Família Multigênica , Polienos , Alcamidas Poli-Insaturadas
8.
J Nat Prod ; 84(5): 1638-1648, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33899471

RESUMO

While marine natural products have been investigated for anticancer drug discovery, they are barely screened against rare cancers. Thus, in our effort to discover potential drug leads against the rare cancer pseudomyxoma peritonei (PMP), which currently lacks effective drug treatments, we screened extracts of marine actinomycete bacteria against the PMP cell line ABX023-1. This effort led to the isolation of nine rearranged angucyclines from Streptomyces sp. CNZ-748, including five new analogues, namely, grincamycins P-T (1-5). The chemical structures of these compounds were unambiguously established based on spectroscopic and chemical analyses. Particularly, grincamycin R (3) possesses an S-containing α-l-methylthio-aculose residue, which was discovered in nature for the first time. All of the isolated compounds were evaluated against four PMP cell lines and some exhibited low micromolar inhibitory activities. To identify a candidate biosynthetic gene cluster (BGC) encoding the grincamycins, we sequenced the genome of the producing strain, Streptomyces sp. CNZ-748, and compared the BGCs detected with those linked to the production of angucyclines with different aglycon structures.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Pseudomixoma Peritoneal/tratamento farmacológico , Streptomyces/química , Antraquinonas/isolamento & purificação , Antineoplásicos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , California , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Sedimentos Geológicos/microbiologia , Humanos , Estrutura Molecular , Família Multigênica , Streptomyces/genética
9.
Int J Syst Evol Microbiol ; 70(8): 4668-4682, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32701422

RESUMO

Ten representative actinobacterial strains isolated from marine sediments collected worldwide were studied to determine their taxonomic status. The strains were previously identified as members of the genus Salinispora and shared >99 % 16S rRNA gene sequence similarity to the three currently recognized Salinispora species. Comparative genomic analyses resulted in the delineation of six new species based on average nucleotide identity and digital DNA-DNA hybridization values below 95 and 70 %, respectively. The species status of the six new groups was supported by a core-genome phylogeny reconstructed from 2106 orthologs detected in 118 publicly available Salinispora genomes. Chemotaxonomic and physiological studies were used to complete the phenotypic characterization of the strains. The fatty acid profiles contained the major components iso-C16 : 0, C15 : 0, iso-17 : 0 and anteiso C17 : 0. Galactose and xylose were common in all whole-sugar patterns but differences were found between the six groups of strains. Polar lipid compositions were also unique for each species. Distinguishable physiological and biochemical characteristics were also recorded. The names proposed are Salinispora cortesiana sp. nov., CNY-202T (=DSM 108615T=CECT 9739T); Salinispora fenicalii sp. nov., CNT-569T (=DSM 108614T=CECT 9740T); Salinispora goodfellowii sp. nov., CNY-666T (=DSM 108616T=CECT 9738T); Salinispora mooreana sp. nov., CNT-150T (=DSM 45549T=CECT 9741T); Salinispora oceanensis sp. nov., CNT-138T (=DSM 45547T=CECT 9742T); and Salinispora vitiensis sp. nov., CNT-148T (=DSM 45548T=CECT 9743T).


Assuntos
Sedimentos Geológicos/microbiologia , Micromonosporaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
J Bacteriol ; 201(7)2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30642989

RESUMO

The airway fluids of cystic fibrosis (CF) patients contain local pH gradients and are more acidic than those of healthy individuals. pH is a critical factor that is often overlooked in studies seeking to recapitulate the infection microenvironment. We sought to determine the impact of pH on the physiology of a ubiqituous yet understudied microbe, Stenotrophomonas maltophilia Phylogenomics was first used to reconstruct evolutionary relationships between 74 strains of S. maltophilia (59 from CF patients). Neither the core genome (2,158 genes) nor the accessory genome (11,978 genes) distinguish the CF and non-CF isolates; however, strains from similar isolation sources grouped into the same subclades. We grew two human and six CF S. maltophilia isolates from different subclades at a range of pH values and observed impaired growth and altered antibiotic tolerances at pH 5. Transcriptomes revealed increased expression of both antibiotic resistance and DNA repair genes in acidic conditions. Although the gene expression profiles of S. maltophilia in lab cultures and CF sputum were distinct, we found that the same genes associated with low pH were also expressed during infection, and the higher pH cultures were more similar to sputum metatranscriptomes. Our findings suggest that S. maltophilia is not well adapted to acidity and may cope with low pH by expressing stress response genes and colonizing less acidic microenvironments. As a whole, our study underlines the impact of microenvironments on bacterial colonization and adaptation in CF infections.IMPORTANCE Understanding bacterial responses to physiological conditions is an important priority for combating opportunistic infections. The majority of CF patients succumb to inflammation and necrosis in the airways, arising from chronic infection due to ineffective mucociliary clearance. Steep pH gradients characterize the CF airways but are not often incorporated in standard microbiology culture conditions. Stenotrophomonas maltophilia is a prevalent CF opportunistic pathogen also found in many disparate environments, yet this bacterium's contribution to CF lung damage and its response to changing environmental factors remain largely understudied. Here, we show that pH impacts the physiology and antibiotic susceptibility of S. maltophilia, with implications for the development of relevant in vitro models and assessment of antibiotic sensitivity.


Assuntos
Adaptação Fisiológica , Fibrose Cística/complicações , Infecções por Bactérias Gram-Negativas/microbiologia , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/fisiologia , Perfilação da Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Stenotrophomonas maltophilia/genética , Stenotrophomonas maltophilia/isolamento & purificação
12.
Environ Microbiol ; 20(11): 4112-4126, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30209883

RESUMO

The high diversity of soil bacteria is attributed to the spatial complexity of soil systems, where habitat heterogeneity promotes niche partitioning among bacterial taxa. This premise remains challenging to test, however, as it requires quantifying the traits of closely related soil bacteria and relating these traits to bacterial abundances and geographic distributions. Here, we sought to investigate whether the widespread soil taxon Curtobacterium consists of multiple coexisting ecotypes with differential geographic distributions. We isolated Curtobacterium strains from six sites along a climate gradient and assayed four functional traits that may contribute to niche partitioning in leaf litter, the top layer of soil. Our results revealed that cultured isolates separated into fine-scale genetic clusters that reflected distinct suites of phenotypic traits, denoting the existence of multiple ecotypes. We then quantified the distribution of Curtobacterium by analysing metagenomic data collected across the gradient over 18 months. Six abundant ecotypes were observed with differential abundances along the gradient, suggesting fine-scale niche partitioning. However, we could not clearly explain observed geographic distributions of ecotypes by relating their traits to environmental variables. Thus, while we can resolve soil bacterial ecotypes, the traits delineating their distinct niches in the environment remain unclear.


Assuntos
Bactérias/genética , Ecótipo , Microbiologia do Solo , Bactérias/classificação , Bactérias/isolamento & purificação , Clima , Ecossistema , Folhas de Planta , Solo/química
14.
N Engl J Med ; 369(12): 1115-23, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-23991625

RESUMO

BACKGROUND: In acute ST-segment elevation myocardial infarction (STEMI), the use of percutaneous coronary intervention (PCI) to treat the artery responsible for the infarct (infarct, or culprit, artery) improves prognosis. The value of PCI in noninfarct coronary arteries with major stenoses (preventive PCI) is unknown. METHODS: From 2008 through 2013, at five centers in the United Kingdom, we enrolled 465 patients with acute STEMI (including 3 patients with left bundle-branch block) who were undergoing infarct-artery PCI and randomly assigned them to either preventive PCI (234 patients) or no preventive PCI (231 patients). Subsequent PCI for angina was recommended only for refractory angina with objective evidence of ischemia. The primary outcome was a composite of death from cardiac causes, nonfatal myocardial infarction, or refractory angina. An intention-to-treat analysis was used. RESULTS: By January 2013, the results were considered conclusive by the data and safety monitoring committee, which recommended that the trial be stopped early. During a mean follow-up of 23 months, the primary outcome occurred in 21 patients assigned to preventive PCI and in 53 patients assigned to no preventive PCI (infarct-artery-only PCI), which translated into rates of 9 events per 100 patients and 23 per 100, respectively (hazard ratio in the preventive-PCI group, 0.35; 95% confidence interval [CI], 0.21 to 0.58; P<0.001). Hazard ratios for the three components of the primary outcome were 0.34 (95% CI, 0.11 to 1.08) for death from cardiac causes, 0.32 (95% CI, 0.13 to 0.75) for nonfatal myocardial infarction, and 0.35 (95% CI, 0.18 to 0.69) for refractory angina. CONCLUSIONS: In patients with STEMI and multivessel coronary artery disease undergoing infarct-artery PCI, preventive PCI in noninfarct coronary arteries with major stenoses significantly reduced the risk of adverse cardiovascular events, as compared with PCI limited to the infarct artery. (Funded by Barts and the London Charity; PRAMI Current Controlled Trials number, ISRCTN73028481.).


Assuntos
Angioplastia Coronária com Balão , Estenose Coronária/terapia , Infarto do Miocárdio/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/terapia , Feminino , Seguimentos , Cardiopatias/mortalidade , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Risco , Prevenção Secundária , Resultado do Tratamento
15.
Heart Lung Circ ; 25(12): 1203-1209, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27265645

RESUMO

BACKGROUND: Chronic total occlusion (CTO) revascularisation has a crucial role in contemporary percutaneous coronary intervention (PCI). Procedural success is influenced by disease complexity, calcific burden and patient characteristics but has substantially improved with the implementation of novel hybrid strategies. However, vascular-access related complications remain a cause of morbidity and mortality. This study aimed to assess the effectiveness of fluoroscopic-guided femoral arterial puncture to minimise this risk during CTO PCI. METHODS: Standardised data were retrospectively collected from four high-volume UK CTO centres between September 2011 and November 2013. Demographic, clinical and procedural data (vascular access site, sheath size, anticoagulation use) was collated. The anatomical location of the femoral puncture in relation to the femoral bifurcation, femoral head position and inferior epigastric artery were recorded. Adverse events related to vascular access were documented. RESULTS: A total of 528 patients were included (676 femoral punctures) with the majority being male (n=432, 81.8%). Large sheaths (8F) were used in 81.2% of cases. Fluoroscopy-enabled punctures were made in the 'safe zone' in over > 93% of cases. Vascular closure devices (VCD) were used in 88.3% of cases. The adverse event rate per puncture was 0.89%. CONCLUSIONS: This study demonstrates an extremely low incidence of vascular-access complications in CTO PCI when fluoroscopic guidance is used to obtain femoral arterial access by default radial operators.


Assuntos
Artéria Femoral , Punções/efeitos adversos , Punções/métodos , Adulto , Assistência ao Convalescente , Idoso , Idoso de 80 Anos ou mais , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Fluoroscopia , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Reino Unido
16.
FEMS Microbiol Ecol ; 100(8)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39020097

RESUMO

Leaf litter microbes collectively degrade plant polysaccharides, influencing land-atmosphere carbon exchange. An open question is how substrate complexity-defined as the structure of the saccharide and the amount of external processing by extracellular enzymes-influences species interactions. We tested the hypothesis that monosaccharides (i.e. xylose) promote negative interactions through resource competition, and polysaccharides (i.e. xylan) promote neutral or positive interactions through resource partitioning or synergism among extracellular enzymes. We assembled a three-species community of leaf litter-degrading bacteria isolated from a grassland site in Southern California. In the polysaccharide xylan, pairs of species stably coexisted and grew equally in coculture and in monoculture. Conversely, in the monosaccharide xylose, competitive exclusion and negative interactions prevailed. These pairwise dynamics remained consistent in a three-species community: all three species coexisted in xylan, while only two species coexisted in xylose, with one species capable of using peptone. A mathematical model showed that in xylose these dynamics could be explained by resource competition. Instead, the model could not predict the coexistence patterns in xylan, suggesting other interactions exist during biopolymer degradation. Overall, our study shows that substrate complexity influences species interactions and patterns of coexistence in a synthetic microbial community of leaf litter degraders.


Assuntos
Bactérias , Interações Microbianas , Folhas de Planta , Poaceae , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Bactérias/metabolismo , Ecossistema , Especificidade da Espécie , Xilanos/metabolismo , Xilose/metabolismo , Modelos Teóricos , Actinobacteria/crescimento & desenvolvimento , Actinobacteria/metabolismo , Bacteroidetes/crescimento & desenvolvimento , Bacteroidetes/metabolismo , Proteobactérias/crescimento & desenvolvimento , Proteobactérias/metabolismo , Interações Microbianas/fisiologia , Poaceae/microbiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-38604832

RESUMO

BACKGROUND: The impact of new-onset left bundle branch block (N-LBBB) developing after Transcatheter Aortic Valve Replacement (TAVR) on cardiac function and mechanical dyssynchrony is not well defined. METHODS: We retrospectively screened all patients who underwent TAVR in our centre between Oct 2018 and Sept 2021 (n = 409). We identified 38 patients with N-LBBB post-operatively (of which 28 were persistent and 10 were transient), and 17 patients with chronic pre-existent LBBB (C-LBBB). We excluded patients requiring pacing post TAVR. For all groups, we retrospectively analysed stored echocardiograms at 3 time points: before TAVR (T0), early after TAVR (T1, 1.2 ± 1.1 days), and late follow-up (T2, 1.5 ± 0.8 years), comparing LV mass and volumes, indices of LV function (LV ejection fraction, LVEF; global longitudinal strain, GLS), and mechanical dyssynchrony indices (systolic stretch index, severity of septal flash). RESULTS: At baseline (T0), C-LBBB had worse cardiac function, and larger LV volumes and LV mass, compared with patients with N-LBBB. At T1, N-LBBB resulted in mild dyssynchrony and decreased LVEF and GLS. Dyssynchrony progressed at T2 in persistent N-LBBB but not C-LBBB. In both groups however, LVEF remained stable at T2, although individual response was variable. Patients with better LVEF at baseline demonstrated a higher proportion of developing LBBB-induced LV dysfunction at T2. Lack of improvement of LVEF immediately after TAVR predicted deteriorating LVEF at T2. In transient LBBB, cardiac function and most dyssynchrony indices returned to baseline. CONCLUSIONS: N-LBBB after TAVR results in an immediate reduction of cardiac function, in spite of only mild dyssynchrony. When LBBB persists, patients with better cardiac function before TAVR are more likely to have LBBB-induced LV dysfunction after TAVR.

18.
Nat Commun ; 15(1): 5230, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898025

RESUMO

Culture-based microbial natural product discovery strategies fail to realize the extraordinary biosynthetic potential detected across earth's microbiomes. Here we introduce Small Molecule In situ Resin Capture (SMIRC), a culture-independent method to obtain natural products directly from the environments in which they are produced. We use SMIRC to capture numerous compounds including two new carbon skeletons that were characterized using NMR and contain structural features that are, to the best of our knowledge, unprecedented among natural products. Applications across diverse marine habitats reveal biome-specific metabolomic signatures and levels of chemical diversity in concordance with sequence-based predictions. Expanded deployments, in situ cultivation, and metagenomics facilitate compound discovery, enhance yields, and link compounds to candidate producing organisms, although microbial community complexity creates challenges for the later. This compound-first approach to natural product discovery provides access to poorly explored chemical space and has implications for drug discovery and the detection of chemically mediated biotic interactions.


Assuntos
Produtos Biológicos , Descoberta de Drogas , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Descoberta de Drogas/métodos , Metabolômica/métodos , Microbiota , Metagenômica/métodos , Espectroscopia de Ressonância Magnética , Bibliotecas de Moléculas Pequenas/química
19.
Heart ; 110(7): 500-507, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38103913

RESUMO

OBJECTIVE: To investigate whether a very early invasive strategy (IS)±revascularisation improves clinical outcomes compared with standard care IS in higher risk patients with non-ST-elevation acute coronary syndrome (NSTE-ACS). METHODS: Multicentre, randomised, controlled, pragmatic strategy trial of higher risk patients with NSTE-ACS, defined by Global Registry of Acute Coronary Events 2.0 score of ≥118, or ≥90 with at least one additional high-risk feature. Participants were randomly assigned to very early IS±revascularisation (<90 min from randomisation) or standard care IS±revascularisation (<72 hours). The primary outcome was a composite of all-cause mortality, new myocardial infarction or hospitalisation for heart failure at 12 months. RESULTS: The trial was discontinued early by the funder due to slow recruitment during the COVID-19 pandemic. 425 patients were randomised, of whom 413 underwent an IS: 204 to very early IS (median time from randomisation: 1.5 hours (IQR: 0.9-2.0)) and 209 to standard care IS (median: 44.0 hours (IQR: 22.9-72.6)). At 12 months, there was no significant difference in the primary outcome between the early IS (5.9%) and standard IS (6.7%) groups (OR 0.93, 95% CI 0.42 to 2.09; p=0.86). The incidence of stroke and major bleeding was similar. The length of hospital stay was reduced with a very early IS (3.9 days (SD 6.5) vs 6.3 days (SD 7.6), p<0.01). CONCLUSIONS: A strategy of very early IS did not improve clinical outcomes compared with a standard care IS in higher risk patients with NSTE-ACS. However, the primary outcome rate was low and the trial was underpowered to detect such a difference. TRIAL REGISTRATION NUMBER: NCT03707314.


Assuntos
Síndrome Coronariana Aguda , Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Humanos , Síndrome Coronariana Aguda/diagnóstico , Pandemias , Resultado do Tratamento , Angiografia Coronária , Intervenção Coronária Percutânea/efeitos adversos
20.
J Invasive Cardiol ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38471155

RESUMO

OBJECTIVES: Cardiac surgery for coronary artery disease was dramatically reduced during the first wave of the COVID-19 pandemic. Many patients with disease ordinarily treated with coronary artery bypass grafting (CABG) instead underwent percutaneous coronary intervention (PCI). We sought to describe 12-month outcomes following PCI in patients who would typically have undergone CABG. METHODS: Between March 1 and July 31, 2020, patients who received revascularization with PCI when CABG would have been the primary choice of revascularization were enrolled in the prospective, multicenter UK-ReVasc Registry. We evaluated the following major adverse cardiovascular events at 12 months: all-cause mortality, myocardial infarction, repeat revascularization, stroke, major bleeding, and stent thrombosis. RESULTS: A total of 215 patients were enrolled across 45 PCI centers in the United Kingdom. Twelve-month follow up data were obtained for 97% of the cases. There were 9 deaths (4.3%), 5 myocardial infarctions (2.4%), 12 repeat revascularizations (5.7%), 1 stroke (0.5%), 3 major bleeds (1.4%), and no cases of stent thrombosis. No difference in the primary endpoint was observed between patients who received complete vs incomplete revascularization (residual SYNTAX score £ 8 vs > 8) (P = .22). CONCLUSIONS: In patients with patterns of coronary disease in whom CABG would have been the primary therapeutic choice outside of the pandemic, PCI was associated with acceptable outcomes at 12 months of follow-up. Contemporary randomized trials that compare PCI to CABG in such patient cohorts may be warranted.

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