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1.
J Minim Invasive Gynecol ; 29(2): 243-249, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34400353

RESUMO

STUDY OBJECTIVE: Evaluation of the efficacy of different injection sites of methotrexate in the treatment of nontubal ectopic pregnancies. DESIGN: Retrospective multicenter study. SETTING: Multicenter, including 3 teaching hospitals, an intercommunal hospital, and a clinic. PATIENTS: A total of 106 patients with nontubal ectopic pregnancies, including 59 interstitial, 39 cesarean scar, and 8 cervical or isthmic. INTERVENTIONS: Overall, 58 patients received methotrexate via intramuscular injection (IM group), 35 received methotrexate via in situ injection (IS group), and 13 received a combination of both in situ and intramuscular injections of methotrexate (IS + IM group). MEASUREMENTS AND MAIN RESULTS: The main end point of this study was measured via the primary success rate (defined as a negative ß-human chorionic gonadotropin level without recourse to any additional treatment) of treatment with methotrexate according to injection site. The primary success rate was 46.55% in the IM group, 60% in the IS group, and 61.54% in the IS + IM group, respectively. In the multivariate analysis, the primary success rate of treatment was significantly correlated to the in situ injection of methotrexate, either solely or in conjunction with an intramuscular injection of methotrexate administered the following day, (odds ratio = 2.7; 95% confidence interval, 1.03-7.14). CONCLUSION: Solely an intramuscular injection of methotrexate is a less efficient first-line treatment strategy for the conservative management of nontubular ectopic pregnancy. The use of an in situ injection of methotrexate should therefore be preferred.


Assuntos
Abortivos não Esteroides , Gravidez Ectópica , Abortivos não Esteroides/uso terapêutico , Feminino , Humanos , Injeções Intramusculares , Metotrexato/uso terapêutico , Gravidez , Gravidez Ectópica/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
2.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36499433

RESUMO

Pseudomonas fluorescens SBW25 is a model soil- and plant-associated bacterium capable of forming a variety of air-liquid interface biofilms in experimental microcosms and on plant surfaces. Previous investigations have shown that cellulose is the primary structural matrix component in the robust and well-attached Wrinkly Spreader biofilm, as well as in the fragile Viscous Mass biofilm. Here, we demonstrate that both biofilms include extracellular DNA (eDNA) which can be visualized using confocal laser scanning microscopy (CLSM), quantified by absorbance measurements, and degraded by DNase I treatment. This eDNA plays an important role in cell attachment and biofilm development. However, exogenous high-molecular-weight DNA appears to decrease the strength and attachment levels of mature Wrinkly Spreader biofilms, whereas low-molecular-weight DNA appears to have little effect. Further investigation with CLSM using an amyloid-specific fluorophore suggests that the Wrinkly Spreader biofilm might also include Fap fibers, which might be involved in attachment and contribute to biofilm strength. The robust nature of the Wrinkly Spreader biofilm also allowed us, using MALDI-TOF mass spectrometry, to identify matrix-associated proteins unable to diffuse out of the structure, as well as membrane vesicles which had a different protein profile compared to the matrix-associated proteins. CLSM and DNase I treatment suggest that some vesicles were also associated with eDNA. These findings add to our understanding of the matrix components in this model pseudomonad, and, as found in other biofilms, biofilm-specific products and material from lysed cells contribute to these structures through a range of complex interactions.


Assuntos
Amiloide , Pseudomonas fluorescens , Biofilmes , Desoxirribonuclease I/metabolismo , DNA/metabolismo , DNA Bacteriano/genética , Pseudomonas fluorescens/metabolismo
3.
Int J Mol Sci ; 23(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35054915

RESUMO

The choice of effective biocides used for routine hospital practice should consider the role of disinfectants in the maintenance and development of local resistome and how they might affect antibiotic resistance gene transfer within the hospital microbial population. Currently, there is little understanding of how different biocides contribute to eDNA release that may contribute to gene transfer and subsequent environmental retention. Here, we investigated how different biocides affect the release of eDNA from mature biofilms of two opportunistic model strains Pseudomonas aeruginosa ATCC 27853 (PA) and Staphylococcus aureus ATCC 25923 (SA) and contribute to the hospital resistome in the form of surface and water contaminants and dust particles. The effect of four groups of biocides, alcohols, hydrogen peroxide, quaternary ammonium compounds, and the polymeric biocide polyhexamethylene guanidine hydrochloride (PHMG-Cl), was evaluated using PA and SA biofilms. Most biocides, except for PHMG-Cl and 70% ethanol, caused substantial eDNA release, and PHMG-Cl was found to block biofilm development when used at concentrations of 0.5% and 0.1%. This might be associated with the formation of DNA-PHMG-Cl complexes as PHMG-Cl is predicted to bind to AT base pairs by molecular docking assays. PHMG-Cl was found to bind high-molecular DNA and plasmid DNA and continued to inactivate DNA on surfaces even after 4 weeks. PHMG-Cl also effectively inactivated biofilm-associated antibiotic resistance gene eDNA released by a pan-drug-resistant Klebsiella strain, which demonstrates the potential of a polymeric biocide as a new surface-active agent to combat the spread of antibiotic resistance in hospital settings.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Desinfetantes/farmacologia , Guanidinas/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , DNA Bacteriano/química , Desinfetantes/química , Guanidinas/síntese química , Guanidinas/química , Conformação de Ácido Nucleico/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Relação Estrutura-Atividade
4.
Microbiology (Reading) ; 166(8): 707-716, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32520698

RESUMO

Model bacterial biofilm systems suggest that bacteria produce one type of biofilm, which is then modified by environmental and physiological factors, although the diversification of developing populations might result in the appearance of adaptive mutants producing altered structures with improved fitness advantage. Here we compare the air-liquid (A-L) interface viscous mass (VM) biofilm produced by Pseudomonas fluorescens SBW25 and the wrinkly spreader (WS) and complementary biofilm-forming strain (CBFS) biofilm types produced by adaptive SBW25 mutants in order to better understand the link between these physical structures and the fitness advantage they provide in experimental microcosms. WS, CBFS and VM biofilms can be differentiated by strength, attachment levels and rheology, as well as by strain characteristics associated with biofilm formation. Competitive fitness assays demonstrate that they provide similar advantages under static growth conditions but respond differently to increasing levels of physical disturbance. Pairwise competitions between biofilms suggest that these strains must be competing for at least two growth-limiting resources at the A-L interface, most probably O2 and nutrients, although VM and CBFS cells located lower down in the liquid column might provide an additional fitness advantage through the colonization of a less competitive zone below the biofilm. Our comparison of different SBW25 biofilm types illustrates more generally how varied biofilm characteristics and fitness advantage could become among adaptive mutants arising from an ancestral biofilm-forming strain and raises the question of how significant these changes might be in a range of medical, biotechnological and industrial contexts where diversification and change may be problematic.


Assuntos
Biofilmes , Pseudomonas fluorescens/fisiologia , Adaptação Fisiológica/genética , Aderência Bacteriana , Biofilmes/crescimento & desenvolvimento , Evolução Biológica , Interações Microbianas , Mutação , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/crescimento & desenvolvimento , Reologia , Viscosidade
5.
Microbiology (Reading) ; 165(10): 1061-1074, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31436522

RESUMO

In radiating populations of Pseudomonas fluorescens SBW25, adaptive wrinkly spreader (WS) mutants are able to gain access to the air-liquid (A-L) interface of static liquid microcosms and achieve a significant competitive fitness advantage over other non-biofilm-forming competitors. Aerotaxis and flagella-based swimming allows SBW25 cells to move into the high-O2 region located at the top of the liquid column and maintain their position by countering the effects of random cell diffusion, convection and disturbance (i.e. physical displacement). However, wild-type cells showed significantly lower levels of enrichment in this region compared to the archetypal WS, indicating that WS cells employ an additional mechanism to transfer to the A-L interface where displacement is no longer an issue and a biofilm can develop at the top of the liquid column. Preliminary experiments suggest that this might be achieved through the expression of an as yet unidentified surface active agent that is weakly associated with WS cells and alters liquid surface tension, as determined by quantitative tensiometry. The effect of physical displacement on the colonization of the high-O2 region and A-L interface was reduced through the addition of agar or polyethylene glycol to increase liquid viscosity, and under these conditions the competitive fitness of the WS was significantly reduced. These observations suggest that the ability to transfer to the A-L interface from the high-O2 region and remain there without further expenditure of energy (through, for example, the deployment of flagella) is a key evolutionary innovation of the WS, as it allows subsequent biofilm development and significant population increase, thereby affording these adaptive mutants a competitive fitness advantage over non-biofilm-forming competitors located within the liquid column.


Assuntos
Biofilmes/crescimento & desenvolvimento , Pseudomonas fluorescens/fisiologia , Aderência Bacteriana/genética , Evolução Biológica , Meio Ambiente , Flagelos/genética , Aptidão Genética , Oxigênio/metabolismo , Fenótipo , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/crescimento & desenvolvimento , Tensão Superficial , Resposta Táctica , Viscosidade
6.
Mol Ecol ; 26(10): 2757-2764, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28247474

RESUMO

Bacteria engage in a complex network of ecological interactions, which includes mobile genetic elements (MGEs) such as phages and plasmids. These elements play a key role in microbial communities as vectors of horizontal gene transfer but can also be important sources of selection for their bacterial hosts. In natural communities, bacteria are likely to encounter multiple MGEs simultaneously and conflicting selection among MGEs could alter the bacterial evolutionary response to each MGE. Here, we test the effect of interactions with multiple MGEs on bacterial molecular evolution in the tripartite interaction between the bacterium, Pseudomonas fluorescens, the lytic bacteriophage, SBW25φ2, and conjugative plasmid, pQBR103, using genome sequencing of experimentally evolved bacteria. We show that individually, both plasmids and phages impose selection leading to bacterial evolutionary responses that are distinct from bacterial populations evolving without MGEs, but that together, plasmids and phages impose conflicting selection on bacteria, constraining the evolutionary responses observed in pairwise interactions. Our findings highlight the likely difficulties of predicting evolutionary responses to multiple selective pressures from the observed evolutionary responses to each selective pressure alone. Understanding evolution in complex microbial communities comprising many species and MGEs will require that we go beyond studies of pairwise interactions.


Assuntos
Bacteriófagos/genética , Evolução Molecular , Plasmídeos/genética , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/virologia , Seleção Genética , Transferência Genética Horizontal
7.
Nature ; 464(7286): 275-8, 2010 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-20182425

RESUMO

The Red Queen hypothesis proposes that coevolution of interacting species (such as hosts and parasites) should drive molecular evolution through continual natural selection for adaptation and counter-adaptation. Although the divergence observed at some host-resistance and parasite-infectivity genes is consistent with this, the long time periods typically required to study coevolution have so far prevented any direct empirical test. Here we show, using experimental populations of the bacterium Pseudomonas fluorescens SBW25 and its viral parasite, phage Phi2 (refs 10, 11), that the rate of molecular evolution in the phage was far higher when both bacterium and phage coevolved with each other than when phage evolved against a constant host genotype. Coevolution also resulted in far greater genetic divergence between replicate populations, which was correlated with the range of hosts that coevolved phage were able to infect. Consistent with this, the most rapidly evolving phage genes under coevolution were those involved in host infection. These results demonstrate, at both the genomic and phenotypic level, that antagonistic coevolution is a cause of rapid and divergent evolution, and is likely to be a major driver of evolutionary change within species.


Assuntos
Bacteriófagos/fisiologia , Evolução Biológica , Evolução Molecular , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/virologia , Bacteriófagos/genética , Variação Genética , Dados de Sequência Molecular , Fenótipo , Seleção Genética/genética
8.
World J Surg ; 40(3): 665-71, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26744341

RESUMO

PURPOSE: This study evaluated the efficiency of transcutaneous laryngeal ultrasonography (TLUS) as an alternative to direct flexible laryngoscopy (DFL) in the early postoperative screening of vocal cord palsy (VCP) after total thyroidectomy, performed for benign and non-extensive malignant disease. METHODS: A prospective study was performed on patients who underwent total thyroidectomy between October 2013 and January 2015 at the Nantes University Hospital (France). Patients underwent DFL on postoperative day 1 performed by an otolaryngologist, followed by TLUS performed by a radiologist on postoperative day 1 or 2. RESULTS: One hundred and three (103) patients were included in this study, 17.5% were male and 82.5% were female, with a mean age of 51 ± 12 years. Nine patients (9.5%) were diagnosed with postoperative VCP using DFL of these cases 2 were not completely resolved at 3 months postoperatively. Three cases of VCP (33%) were diagnosed using TLUS. TLUS had a sensitivity of 33% and a negative predictive value (NPV) of 95% for the diagnosis of postoperative VCP. Vocal cords (VC) were unassessable in 27.2% of patients. Unassessable VC were significantly associated with male gender (p = 0.0001), age (p = 0.0001), weight (p = 0.002), operating time (p = 0.032), postoperative drainage (p = 0.001), and thyroid weight (p = 0.001). Independent risk factors in the multivariate analysis were male gender (p = 0.0001) and age (p = 0.0001). In the group of women under 50-year old, TLUS had a sensitivity of 50% and a NPV of 97.4%. CONCLUSION: TLUS sensitivity is insufficient in early postoperative screening of VCP after thyroid surgery. Ultrasonographic VCP diagnosis should be confirmed with DFL.


Assuntos
Diagnóstico Precoce , Complicações Pós-Operatórias/diagnóstico por imagem , Tireoidectomia/efeitos adversos , Paralisia das Pregas Vocais/diagnóstico por imagem , Prega Vocal/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Fatores de Risco , Doenças da Glândula Tireoide/cirurgia , Fatores de Tempo , Ultrassonografia , Paralisia das Pregas Vocais/etiologia
9.
Environ Microbiol ; 17(12): 5008-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25969927

RESUMO

Plasmids are important mobile elements that can facilitate genetic exchange and local adaptation within microbial communities. We compared the sequences of four co-occurring pQBR family environmental mercury resistance plasmids and measured their effects on competitive fitness of a Pseudomonas fluorescens SBW25 host, which was isolated at the same field site. Fitness effects of carriage differed between plasmids and were strongly context dependent, varying with medium, plasmid status of competitor and levels of environmental mercury. The plasmids also varied widely in their rates of conjugation and segregational loss. We found that few of the plasmid-borne accessory genes could be ascribed functions, although we identified a putative chemotaxis operon, a type IV pilus-encoding cluster and a region encoding putative arylsulfatase enzymes, which were conserved across geographically distant isolates. One plasmid, pQBR55, conferred the ability to catabolize sucrose. Transposons, including the mercury resistance Tn5042, appeared to have been acquired by different pQBR plasmids by recombination, indicating an important role for horizontal gene transfer in the recent evolution of pQBR plasmids. Our findings demonstrate extensive genetic and phenotypic diversity among co-occurring members of a plasmid community and suggest a role for environmental heterogeneity in the maintenance of plasmid diversity.


Assuntos
Elementos de DNA Transponíveis/genética , Farmacorresistência Bacteriana/genética , Mercúrio/farmacologia , Plasmídeos/genética , Pseudomonas fluorescens/efeitos dos fármacos , Pseudomonas fluorescens/genética , Arilsulfatases/genética , Meio Ambiente , Transferência Genética Horizontal , Óperon/genética , Pseudomonas fluorescens/isolamento & purificação , Microbiologia do Solo , Sacarose/metabolismo
10.
Biol Lett ; 11(8)2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26268992

RESUMO

Coevolution with bacteriophages is a major selective force shaping bacterial populations and communities. A variety of both environmental and genetic factors has been shown to influence the mode and tempo of bacteria-phage coevolution. Here, we test the effects that carriage of a large conjugative plasmid, pQBR103, had on antagonistic coevolution between the bacterium Pseudomonas fluorescens and its phage, SBW25ϕ2. Plasmid carriage limited bacteria-phage coevolution; bacteria evolved lower phage-resistance and phages evolved lower infectivity in plasmid-carrying compared with plasmid-free populations. These differences were not explained by effects of plasmid carriage on the costs of phage resistance mutations. Surprisingly, in the presence of phages, plasmid carriage resulted in the evolution of high frequencies of mucoid bacterial colonies. Mucoidy can provide weak partial resistance against SBW25ϕ2, which may have limited selection for qualitative resistance mutations in our experiments. Taken together, our results suggest that plasmids can have evolutionary consequences for bacteria that go beyond the direct phenotypic effects of their accessory gene cargo.


Assuntos
Evolução Biológica , Fagos de Pseudomonas/genética , Pseudomonas fluorescens/genética , Evolução Molecular , Mutação , Plasmídeos , Pseudomonas fluorescens/crescimento & desenvolvimento , Pseudomonas fluorescens/virologia
11.
Front Cell Infect Microbiol ; 14: 1374817, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779563

RESUMO

Introduction: Periodontal diseases are known to be associated with polymicrobial biofilms and inflammasome activation. A deeper understanding of the subgingival cytological (micro) landscape, the role of extracellular DNA (eDNA) during periodontitis, and contribution of the host immune eDNA to inflammasome persistence, may improve our understanding of the mechanisms underlaying severe forms of periodontitis. Methods: In this work, subgingival biolfilms developing on biologically neutral polyethylene terephthalate films placed in gingival cavities of patients with chronic periodontitis were investigated by confocal laser scanning microscopy (CLSM). This allowed examination of realistic cytological landscapes and visualization of extracellular polymeric substances (EPS) including amyloids, total proteins, carbohydrates and eDNA, as well as comparison with several single-strain in vitro model biofilms produced by oral pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus gordonii, S. sanguinis and S. mitis. Fluorescence in situ hybridization (FISH) analysis was also used to identify eDNA derived from eubacteria, streptococci and members of the Bacteroides-Porphyromonas-Prevotella (BPP) group associated with periodontitis. Results: Analysis of subgingival biofilm EPS revealed low levels of amyloids and high levels of eDNA which appears to be the main matrix component. However, bacterial eDNA contributed less than a third of the total eDNA observed, suggesting that host-derived eDNA released in neutrophil extracellular traps may be of more importance in the development of biofilms causing periodontitis. Discussion: eDNA derived from host immunocompetent cells activated at the onset of periodontitis may therefore be a major driver of bacterial persistence and pathogenesis.


Assuntos
Biofilmes , Periodontite , Biofilmes/crescimento & desenvolvimento , Humanos , Periodontite/microbiologia , Microscopia Confocal , DNA , Hibridização in Situ Fluorescente , Bactérias/genética , DNA Bacteriano/genética , Inflamassomos/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Gengiva/microbiologia , Periodontite Crônica/microbiologia , Periodontite Crônica/imunologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-39161277

RESUMO

Endometriosis is a complex gynecologic disorder characterized primarily by symptoms of pelvic pain, infertility, and altered quality of life. National and international guidelines highlight the diagnostic difficulties and lack of conclusive diagnostic tools for endometriosis. Furthermore, guidelines are becoming questionable at an increasingly rapid rate as new diagnostic techniques emerge. This work aims to provide a knowledge synthesis of the relevance of various diagnostic tools and to assess areas of improvement of conventional algorithms. MEDLINE and Cochrane Library databases were searched from January 2021 to December 2023 using relevant key words. Articles evaluating the diagnostic relevance and performance of various tools were included and independently reviewed by the authors for eligibility. Included studies were assessed using the GRADE and QUADAS-2 tools. Of the 4204 retrieved articles, 26 were included. While anamnesis and clinical examination do contribute to diagnostic accuracy, their level of evidence and impact on the diagnostic process remains limited. Although imaging techniques are recommended to investigate endometriosis, ultrasonography remains highly operator dependent. Magnetic resonance imaging appears to exhibit higher sensitivities than ultrasound. However, concerns persist with regards to the terminology, anatomical definition of lesions, and accuracies of both ultrasound and magnetic resonance imaging. Recently, several biological markers have been studied and cumulative evidence supports the contribution of noncoding RNAs to the diagnosis of endometriosis. Marginal improvements have been suggested for anamnesis, clinical examination, and imaging examinations. Conversely, some biomarkers, including the saliva microRNA signature for endometriosis, have emerged as diagnostic tools which inspire reflection on the revision of conventional diagnostic algorithms.

14.
Antonie Van Leeuwenhoek ; 103(1): 251-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22983557

RESUMO

The ability to colonise the surface of liquids has obvious advantages for bacteria and biofilm formation at the meniscus and air-liquid (A-L) interface is common amongst environmental pseudomonads. Bacteria from this genus also colonise raw meat and in this work the ability of these to produce biofilms was assessed. Sixty isolates were recovered from vacuum-packed venison, phenotypically characterised and shown by hierarchical cluster analysis to represent a diverse collection of psychrotrophic spoilt venison-associated pseudomonads. Of these, 12 % were found to produce biofilms limited to the meniscus region of the microcosm walls, 31 % produced attached biofilms with significant extensions across the A-L interface and 45 % produced unattached 'floating' biofilms. A combined statistical analysis of growth, biofilm strength and attachment levels revealed that growth affected strength but not attachment, and that there was a significant relationship between attachment and strength. Some environmental pseudomonads are known to utilise cellulose as a biofilm matrix component and here 28 % of the SVP isolates were found to express cellulose by epifluorescent microscopy. This survey suggests that biofilm formation may be more common in psychrotrophic meat-associated isolates than amongst the wider pseudomonad community from which spoilage bacteria might be recruited. This may reflect a selective advantage of bacterial aggregations such as biofilms in environments subject to high levels of physical disturbance. Aggregations may be more resistant to competition and dehydration stress than individual bacteria, whilst fragments of these aggregations may prove more effective in the colonisation of new habitats.


Assuntos
Biofilmes/crescimento & desenvolvimento , Carne/microbiologia , Pseudomonas/isolamento & purificação , Pseudomonas/fisiologia , Ar , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Temperatura Baixa , Pseudomonas/classificação , Água
15.
Sci Rep ; 13(1): 4095, 2023 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-36907954

RESUMO

Early Mortality Syndrome (EMS) has been a major problem for shrimp aquaculture in Southeast Asia due to its epizootic prevalence within the region since the first reported case in 2009. This study explores the application of halophilic marine bacilli isolated from coral mucus and their quorum-quenching abilities as potential biocontrol agents in aquaculture systems to combat the causative agent of EMS, Vibrio parahaemolyticus. N-acylhomoserine lactone (AHL)-degrading (AiiA) activity was first screened by PCR then confirmed by bio-reporter assay, and a combination of 16S rDNA sequence analysis and quantitative phenotype assays including biofilm-formation and temperature-growth responses were used to demonstrate diversity amongst these quorum-quenching isolates. Three phenotypically distinct strains showing notable potential were chosen to undergo co-cultivation as a method for strain improvement via long term exposure to the pathogenic V. parahaemolyticus. The novel approach taken led to significant improvements in antagonism and quorum quenching activities as compared to the ancestral wild-type strains and offers a potential solution as well as pathway to improve existing beneficial microbes for one of the most pressing issues in shrimp aquacultures worldwide.


Assuntos
Bacillus , Decápodes , Lacticaseibacillus casei , Vibrio parahaemolyticus , Animais , Percepção de Quorum/genética , Bacillus/metabolismo , Vibrio parahaemolyticus/metabolismo , Acil-Butirolactonas/metabolismo , Decápodes/metabolismo , Crustáceos/metabolismo
16.
PLoS One ; 18(6): e0286540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37267309

RESUMO

Bacteria produce a variety of polysaccharides with functional roles in cell surface coating, surface and host interactions, and biofilms. We have identified an 'Orphan' bacterial cellulose synthase catalytic subunit (BcsA)-like protein found in four model pseudomonads, P. aeruginosa PA01, P. fluorescens SBW25, P. putida KT2440 and P. syringae pv. tomato DC3000. Pairwise alignments indicated that the Orphan and BcsA proteins shared less than 41% sequence identity suggesting they may not have the same structural folds or function. We identified 112 Orphans among soil and plant-associated pseudomonads as well as in phytopathogenic and human opportunistic pathogenic strains. The wide distribution of these highly conserved proteins suggest they form a novel family of synthases producing a different polysaccharide. In silico analysis, including sequence comparisons, secondary structure and topology predictions, and protein structural modelling, revealed a two-domain transmembrane ovoid-like structure for the Orphan protein with a periplasmic glycosyl hydrolase family GH17 domain linked via a transmembrane region to a cytoplasmic glycosyltransferase family GT2 domain. We suggest the GT2 domain synthesises ß-(1,3)-glucan that is transferred to the GH17 domain where it is cleaved and cyclised to produce cyclic-ß-(1,3)-glucan (CßG). Our structural models are consistent with enzymatic characterisation and recent molecular simulations of the PaPA01 and PpKT2440 GH17 domains. It also provides a functional explanation linking PaPAK and PaPA14 Orphan (also known as NdvB) transposon mutants with CßG production and biofilm-associated antibiotic resistance. Importantly, cyclic glucans are also involved in osmoregulation, plant infection and induced systemic suppression, and our findings suggest this novel family of CßG synthases may provide similar range of adaptive responses for pseudomonads.


Assuntos
Polissacarídeos , beta-Glucanas , Humanos , Polissacarídeos/metabolismo , Glucanos , Estrutura Secundária de Proteína , Biofilmes , Pseudomonas aeruginosa/metabolismo , Proteínas de Bactérias/metabolismo , beta-Glucanas/metabolismo
17.
NEJM Evid ; 2(7): EVIDoa2200282, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38320163

RESUMO

BACKGROUND: The discovery of a saliva-based micro­ribonucleic acid (miRNA) signature for endometriosis in 2022 opened up new perspectives for early and noninvasive diagnosis of the disease. The 109-miRNA saliva signature is the product of miRNA biomarkers and artificial intelligence (AI) modeling. We designed a multicenter study to provide external validation of its diagnostic accuracy. We present here an interim analysis. METHODS: The first 200 patients included in the multicenter prospective ENDOmiRNA Saliva Test study (NCT05244668) were included for interim analysis. The study population comprised women from 18 to 43 years of age with a formal diagnosis of endometriosis or with suspected endometriosis. Epidemiologic, clinical, and saliva sequencing data were collected between November 2021 and March 2022. Genomewide miRNA expression profiling by small RNA sequencing using next-generation sequencing (NGS) was performed, and a random forest algorithm was used to assess the diagnostic accuracy. RESULTS: In this interim analysis of the external validation cohort, with a population prevalence of 79.5%, the 109-miRNA saliva diagnostic signature for endometriosis had a sensitivity of 96.2% (95% confidence interval [CI], 93.7 to 97.3%), specificity of 95.1% (95% CI, 85.2 to 99.1%), positive predictive value of 95.1% (95% CI, 85.2 to 99.1%), negative predictive value of 86.7% (95% CI, 77.6 to 90.3%), positive likelihood ratio of 19.7 (95% CI, 6.3 to 108.8), negative likelihood ratio of 0.04 (95% CI, 0.03 to 0.07), and area under the receiver operating characteristic curve of 0.96 (95% CI, 0.92 to 0.98). CONCLUSIONS: The use of NGS and AI in the sequencing and analysis of miRNA provided a saliva-based miRNA signature for endometriosis. Our interim analysis of a prospective multicenter external validation study provides support for its ongoing investigation as a diagnostic tool. (Funded by Ziwig and the Conseil Régional d'Ile de France [Grant EX024087]; ClinicalTrials.gov number, NCT05244668.)


Assuntos
Endometriose , MicroRNAs , Feminino , Humanos , MicroRNAs/genética , Endometriose/diagnóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Biomarcadores Tumorais/genética
18.
J Gynecol Obstet Hum Reprod ; 51(1): 102252, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34638008

RESUMO

A congenital malformation of the head, neck or thorax can lead to upper airway compression with a risk of asphyxia or neonatal death. To secure and protect the upper airway, the Ex Utero Intrapartum Therapy (EXIT) procedure has been developed. The procedure allows delivery of the fetus via a hysterotomy while relying on the placenta as the organ of respiration for the fetus prior to clamping of the umbilical cord. A high level of expertise is necessary for successful completion of the EXIT procedure, which is not void of maternal and fetal risks. In this literature review, we present the indications, procedure methods and materno-fetal complications associated with the EXIT procedure.


Assuntos
Anormalidades Congênitas/cirurgia , Procedimentos para Tratamento Intraparto ex utero/métodos , Adulto , Manuseio das Vias Aéreas/métodos , Manuseio das Vias Aéreas/estatística & dados numéricos , Obstrução das Vias Respiratórias/cirurgia , Procedimentos para Tratamento Intraparto ex utero/efeitos adversos , Procedimentos para Tratamento Intraparto ex utero/tendências , Feminino , Humanos , Complicações Pós-Operatórias/etiologia , Gravidez
19.
Lancet Reg Health Eur ; 12: 100265, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34870255

RESUMO

BACKGROUND: To limit the spread of COVID-19 in March 2020, the population of England was instructed to stay home, leaving only for essential shopping, health-care, work, or exercise. The impact on population activity behaviours is not clear. We describe changes in duration and types of activity undertaken by adults ≥16 years in England between March and May 2016-19 and 2020, by socio-demographic strata. METHODS: Using nationally representative data collected between November 2015 and May 2020 by the Sport England Active Lives Surveys (n=726,257) we assessed trends in amount and type of non-occupational moderate-to-vigorous physical activity. Using data from n=74,430 mid-April to mid-May respondents, we then estimated the odds ratios of reporting any activity in the four-week recall period in 2020 compared to 2016-19. Gamma regressions estimated the mean ratios (MR) of duration amongst those reporting any activity in 2020 compared to 2016-19. FINDINGS: Population activity declined substantially after the restrictions were introduced. Compared to 2016-19 levels, the odds of reporting any activity in 2020 were 30% lower (95% confidence interval (CI) 26-34%). The largest declines were amongst non-white ethnicities, the youngest and oldest age groups, and the unemployed; no socio-demographic subgroup had higher odds. Amongst those undertaking activity, weekly duration was similar in the two periods (MR 0.99, 95%CI (0.96-1.01%)). The odds of participating in walking for leisure and gardening were 11% (6-16%) and 15% (9-21%) higher, respectively, whereas the odds for team and racket sport and walking for travel participation were 76% (73-79%) and 66% (64-68%) lower, respectively. INTERPRETATION: Restrictions introduced in Spring 2020 likely reduced physical activity levels in England. The magnitude of the declines were not uniform by demographic groups or by activity type, which future policies should consider. FUNDING: TS, KW, SJS, and SB are supported by UK Medical Research Council [grant numbers MC_UU_00006/4 and MC_UU_12015/3] and SB is supported by the NIHR Biomedical Research Centre in Cambridge (IS-BRC-1215-20014).

20.
PLoS One ; 17(7): e0270983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35776759

RESUMO

Novel antibiotic combinations may act synergistically to inhibit the growth of multidrug-resistant bacterial pathogens but predicting which combination will be successful is difficult, and standard antimicrobial susceptibility testing may not identify important physiological differences between planktonic free-swimming and biofilm-protected surface-attached sessile cells. Using a nominally macrolide-resistant model Klebsiella pneumoniae strain (ATCC 10031) we demonstrate the effectiveness of several macrolides in inhibiting biofilm growth in multi-well plates, and the ability of azithromycin (AZM) to improve the effectiveness of the antibacterial last-agent-of-choice for K. pneumoniae infections, colistin methanesulfonate (CMS), against biofilms. This synergistic action was also seen in biofilm tests of several K. pneumoniae hospital isolates and could also be identified in polymyxin B disc-diffusion assays on azithromycin plates. Our work highlights the complexity of antimicrobial-resistance in bacterial pathogens and the need to test antibiotics with biofilm models where potential synergies might provide new therapeutic opportunities not seen in liquid culture or colony-based assays.


Assuntos
Infecções por Klebsiella , Pneumonia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Azitromicina/farmacologia , Azitromicina/uso terapêutico , Biofilmes , Colistina/farmacologia , Colistina/uso terapêutico , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae , Mesilatos , Testes de Sensibilidade Microbiana , Pneumonia/tratamento farmacológico , Polimixina B/farmacologia , Polimixina B/uso terapêutico
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