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1.
Braz J Microbiol ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743244

RESUMO

Klebsiella pneumoniae strains are globally associated with a plethora of opportunistic and severe human infections and are known to spread genes conferring antimicrobial resistance. Some strains harbor virulence determinants that enable them to cause serious disease in any patient, both in the hospital and in the community. The aim of this study was to determine the frequency of antimicrobial resistance and virulence traits (by gene detection and string test) among 83 K. pneumoniae isolates obtained from patient cultures of a scholar tertiary hospital in the Midwestern Brazil (Brasília, DF). Antimicrobial susceptibility analysis showed that 94% (78/83) of the isolates presented one of the following resistance profiles: resistant (R, 39), multidrug-resistant (MDR, 29), or extensively drug-resistant (XDR, 10). Several MDR and XDR strains harbored multiple virulence genes and displayed hypermucoviscous phenotype. These characteristics were observed among isolates obtained throughout all the sample collection period (2013 - 2017). The K2 serotype gene, a molecular marker of hypervirulence, was detected in three isolates, one of which classified as XDR. Sequence typing revealed the occurrence of isolates belonged to high-risk (ST13) and multiple resistance-spreading clones (ST105). Thus, our findings showed the occurrence of virulent potential isolates that also presented MDR/XDR phenotypes from 2013 to 2015. This study also indicates the probable convergence of virulence and resistance since at least 2013 in Brazil.

2.
Braz J Microbiol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635155

RESUMO

The health benefits of functional foods are associated with consumer interest and have supported the growth of the market for these types of foods, with emphasis on the development of new formulations based on plant extracts. Therefore, the present study aimed to characterize a symbiotic preparation based on water-soluble soy extract, supplemented with inulin and xylitol and fermented by Lactiplantibacillus plantarum ATCC 8014. Regarding nutritional issues, the symbiotic formulation can be considered a source of fiber (2 g/100 mL) and proteins (2.6 g/100 mL), and it also has a low-fat content and low caloric value. This formulation, in terms of microbiological aspects, remained adequate to legal standards after storage for 60 days under refrigeration and also presented an adequate quantity of the aforementioned probiotic strain, corresponding to 9.11 Log CFU.mL-1. These viable L. plantarum cells proved to be resistant to simulated human gastrointestinal tract conditions, reaching the intestine at high cell concentrations of 7.95 Log CFU.mL-1 after 60 days of refrigeration. Regarding sensory evaluation, the formulation showed good acceptance, presenting an average overall impression score of 6.98, 5.98, and 5.16, for control samples stored for 30 and 60 days under refrigeration, respectively. These results demonstrate that water-soluble soy extract is a suitable matrix for fermentation involving L. plantarum ATCC 8014, supporting and providing data on the first steps towards the development of a symbiotic functional food, targeting consumers who have restrictions regarding the consumption of products of animal origin, diabetics, and individuals under calorie restrictions.

3.
Plant Physiol Biochem ; 208: 108444, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38382344

RESUMO

Under conditions of soil water limitation and adequate irrigation, we conducted an investigation into the growth dynamics, gas exchange performance, and proteomic profiles of two inbred popcorn lines-L71, characterized as drought-tolerant, and L61, identified as drought-sensitive. Our goal was to uncover the mechanisms associated with tolerance to soil water limitation during the flowering. The plants were cultivated until grain filling in a substrate composed of perlite and peat within 150cm long lysimeter, subjected to two water conditions (WC): i) irrigated (WW) at lysimeter capacity (LC - 100%), and ii) water-stressed (WS). Under WS conditions, the plants gradually reached 45% of LC and were maintained at this level for 10 days. Irrespective of the WC, L71 exhibited the highest values of dry biomass in both shoot and root systems, signifying its status as the most robust genotype. The imposed water limitation led to early senescence, chlorophyll degradation, and increased anthocyanin levels, with a more pronounced impact observed in L61. Traits related to gas exchange manifested differences between the lines only under WS conditions. A total of 1838 proteins were identified, with 169 differentially accumulated proteins (DAPs) in the tolerant line and 386 DAPs in the sensitive line. Notably, differences in energy metabolism, photosynthesis, oxidative stress response, and protein synthesis pathways were identified as the key distinctions between L71 and L61. Consequently, our findings offer valuable insights into the alterations in proteomic profiles associated with the adaptation to soil water limitation in popcorn.


Assuntos
Estresse Fisiológico , Zea mays , Zea mays/metabolismo , Estresse Fisiológico/genética , Secas , Proteômica , Solo/química , Água/metabolismo
4.
Curr Diabetes Rev ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38173216

RESUMO

BACKGROUND: The relationship between type II diabetes mellitus (DM) and periodontal disease (PD) has been discussed in recent years and may vary according to the patient's location, sex, age and family history. OBJECTIVE: In view of this possible association between periodontitis and DM, this study aimed to evaluate salivary glucose and salivary cortisol levels with periodontitis (staging and degree) in people with type II diabetes compared to non-diabetic individuals. METHODS: This was a case-control study, with 60 participants divided into two groups: DM2- people with type II diabetes (n=30) and NDM- non-diabetic individuals (n=30). For both, a clinical form and periogram were filled out, and blood samples (glycemia, glycated hemoglobin, and cortisol) and saliva (glucose and cortisol) were collected. RESULTS: The diagnosis of periodontitis was 100% in the DM2 group and 80% in the NDM group. As for staging and degree, in the DM2 group, 70% of the participants were in stage IV and 86.67% were in grade C, while in the NDM group, 58.3% of the participants were in stage I and 70.8% were in grade A. Significant differences were observed for the following variables: bleeding to probing and clinical attachment level. The laboratory data presented significant results regarding serum glucose, salivary glucose, and glycated hemoglobin. CONCLUSION: Regarding the influence of salivary glucose and cortisol on periodontal status (staging and degree), these had higher means in the DM2 group when compared to the NDM group. An association of salivary glucose and cortisol levels with the periodontal condition presented by type II diabetic individuals compared to non-diabetic individuals is suggested.

5.
Br J Haematol ; 204(1): 206-220, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37726227

RESUMO

Progression to aggressive secondary acute myeloid leukaemia (sAML) poses a significant challenge in the management of myeloproliferative neoplasms (MPNs). Since the physiopathology of MPN is closely linked to the activation of interferon (IFN) signalling and that AML initiation and aggressiveness is driven by leukaemia stem cells (LSCs), we investigated these pathways in MPN to sAML progression. We found that high IFN signalling correlated with low LSC signalling in MPN and AML samples, while MPN progression and AML transformation were characterized by decreased IFN signalling and increased LSC signature. A high LSC to IFN expression ratio in MPN patients was associated with adverse clinical prognosis and higher colony forming potential. Moreover, treatment with hypomethylating agents (HMAs) activates the IFN signalling pathway in MPN cells by inducing a viral mimicry response. This response is characterized by double-stranded RNA (dsRNA) formation and MDA5/RIG-I activation. The HMA-induced IFN response leads to a reduction in LSC signature, resulting in decreased stemness. These findings reveal the frequent evasion of viral mimicry during MPN-to-sAML progression, establish the LSC-to-IFN expression ratio as a progression biomarker, and suggests that HMAs treatment can lead to haematological response in murine models by re-activating dsRNA-associated IFN signalling.


Assuntos
Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Humanos , Animais , Camundongos , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Prognóstico , Biomarcadores , Interferons/uso terapêutico
6.
F1000Res ; 12: 1205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970066

RESUMO

Background: Advancements in DNA sequencing technology have transformed the field of bacterial genomics, allowing for faster and more cost effective chromosome level assemblies compared to a decade ago. However, transforming raw reads into a complete genome model is a significant computational challenge due to the varying quality and quantity of data obtained from different sequencing instruments, as well as intrinsic characteristics of the genome and desired analyses. To address this issue, we have developed a set of container-based pipelines using Nextflow, offering both common workflows for inexperienced users and high levels of customization for experienced ones. Their processing strategies are adaptable based on the sequencing data type, and their modularity enables the incorporation of new components to address the community's evolving needs. Methods: These pipelines consist of three parts: quality control, de novo genome assembly, and bacterial genome annotation. In particular, the genome annotation pipeline provides a comprehensive overview of the genome, including standard gene prediction and functional inference, as well as predictions relevant to clinical applications such as virulence and resistance gene annotation, secondary metabolite detection, prophage and plasmid prediction, and more. Results: The annotation results are presented in reports, genome browsers, and a web-based application that enables users to explore and interact with the genome annotation results. Conclusions: Overall, our user-friendly pipelines offer a seamless integration of computational tools to facilitate routine bacterial genomics research. The effectiveness of these is illustrated by examining the sequencing data of a clinical sample of Klebsiella pneumoniae.


Assuntos
Genoma Bacteriano , Software , Análise de Sequência de DNA/métodos , Anotação de Sequência Molecular , Sequência de Bases
7.
Braz J Microbiol ; 54(4): 2705-2718, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37735300

RESUMO

Endophytic fungi constitute a major part of the still unexplored fungal diversity and have gained interest as new biological sources of natural active compounds, including enzymes. Endophytic fungi were isolated from soybean leaves and initially screened on agar plates for the production of CMCase (carboxymethylcellulase), xylanase, amylase and protease. The highest Enzymatic Indexes (IE) were verified for xylanase (2.14 and 1.31) with the fungi M6-A6P5F2 and M12-A5P3F1.2 and CMCase (1.92 and 1.62) with the fungi M13-A9P2F1 and M12-A5P3F1.2, respectively. The production of xylanase and CMCase by the selected fungi was evaluated in submerged cultivation using beechwood xylan and carboxymethylcellulose (CMC), as well as sugarcane straw and bagasse in different ratios as carbon sources. Both types of lignocellulosic biomass proved to be good inducers of enzymatic activity. The best xylanase producer among the isolates was identified as Colletotrichum boninense. With this fungus, the highest xylanase activity was obtained with a sugarcane straw-bagasse mixture in a 50:50 ratio (383.63 U mL-1), a result superior to that obtained with the use of beechwood xylan (296.65 U mL-1). Regardingthe kinetic behavior of the crude xylanase, there was found optimal pH of 5.0 and optimal temperatures of 50°C and 60°C. At 40°C and 50°C, xylanase retained 87% and 76% of its initial catalytic activity, respectively. These results bring new perspectives on bioprospecting endophytic fungi for the production of enzymes, mainly xylanase, as well as the exploitation of agro-industrial by-products, such as sugarcane straw and bagasse.


Assuntos
Saccharum , Xilanos , Saccharum/microbiologia , Biomassa , Fungos
8.
Mol Divers ; 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37658910

RESUMO

Listeria monocytogenes is an important human and animal pathogen able to cause an infection named listeriosis and is mainly transmitted through contaminated food. Among its virulence traits, the ability to form biofilms and to survive in harsh environments stand out and lead to the persistence of L. monocytogenes for long periods in food processing environments. Virulence and biofilm formation are phenotypes regulated by quorum sensing (QS) and, therefore, the control of L. monocytogenes through an anti-QS strategy is promising. This study aimed to identify, by in silico approaches, proteins secreted by lactic acid bacteria (LAB) potentially able to interfere with the agr QS system of L. monocytogenes. The genome mining of Lacticaseibacillus rhamnosus GG and Lactobacillus acidophilus NCFM revealed 151 predicted secreted proteins. Concomitantly, the three-dimensional (3D) structures of AgrB and AgrC proteins of L. monocytogenes were modeled and validated, and their active sites were predicted. Through protein-protein docking and molecular dynamic, Serine-type D-Ala-D-Ala carboxypeptidase and L,D-transpeptidase, potentially secreted by L. rhamnosus GG and L. acidophilus NCFM, respectively, were identified with high affinity to AgrB and AgrC proteins, respectively. By inhibiting the translocation of the cyclic autoinducer peptide (cyclic AIP) via AgrB, and its recognition in the active site of AgrC, these LAB proteins could disrupt L. monocytogenes communication by impairing the agr QS system. The application of the QS inhibitors predicted in this study can emerge as a promising strategy in controlling L. monocytogenes in food processing environment and as an adjunct to antibiotic therapy for the treatment of listeriosis.

9.
Rev Bras Ortop (Sao Paulo) ; 58(3): 471-477, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37396075

RESUMO

Objective To translate and culturally adapt the Long Head of Biceps Tendon (LHB) score into Brazilian Portuguese. Methods The process involved translations by professionals fluent in the target language, followed by independent back translations. Next, a committee compared the original and translated versions, pretested the final version, and concluded it. Results We translated and adapted the questionnaire according to the proposed methodology. In the first version in Portuguese (VP1) there was divergence regarding the translation of twelve terms. Compared to the original version, the back translation of VP1 presented eight diverging terms. A committee prepared a second version in Portuguese (VP2) and applied it to a pretest group consisting of 30 participants. Finally, we conceived the third version in Portuguese, called LHB-pt. Conclusion The translation and cultural adaptation into Brazilian Portuguese of the LBH score was successfully accomplished.

10.
Microorganisms ; 11(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37512901

RESUMO

The Amazonian rainforest is a hyper-diverse ecosystem in the number of species and the myriad of intertaxon relationships that are mostly understudied. In order to characterize a dominant and economically important Amazonian species, the Brazil nut tree (Bertholletia excelsa Bonpl.), at the genome level, wegenerated high-coverage long-read sequencing data from the leaves of a single individual. The genome assembly revealed an unexpected discovery: two circular contigs that could be assigned to the chromosome and a plasmid of a Pantoea stewartii strain. Comparative genomics revealed that this strain belongs to the indologenes subspecies and displays high synteny with other strains isolated from diseased leaves of the neotropical palm Bactris gasipaes Kunth. Investigation of pathogenicity-related genes revealed the absence of the entire type III secretion system gene cluster in the plasmid, which was otherwise highly similar to a plasmid from an isolate known to cause disease in Dracaena sanderiana Mast. In contrast, several genes associated with plant-growth promoting traits were detected, including genes involved in indole-3-acetic acid (IAA) production, phosphate solubilization, and biosynthesis of siderophores. In summary, we report the genome of an uncultivated P. stewartii subsp. indologenes strain associated with the Brazil nut tree and potentially a plant growth-promoting bacteria.

11.
Environ Pollut ; 333: 122016, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37339733

RESUMO

Polyurethanes (PUs) are found in many everyday products and their disposal leads to environmental accumulation. Therefore, there is an urgent need to develop ecologically sustainable techniques to biodegrade and recycle this recalcitrant polymer and replace traditional methods that form harmful by-products. Serratia liquefaciens L135 secretes a polyurethanase with lipase activity, and this study explores the biodegradation of PUs by this bacterium and its enzyme through in silico and in vitro analyses. PUs monomers and tetramers were constructed in silico and tested with modeled and validated structure of the polyurethanase from S. liquefaciens. The molecular docking showed that all PUs monomers presented favorable interactions with polyurethanase (values of binding energy between -84.75 and -121.71 kcal mol-1), including PU poly[4,4'-methylenebis (phenyl isocyanate)-alt-1,4-butanediol/di (propylene glycol)/polycaprolactone] (PCLMDI). Due to repulsive steric interactions, tetramers showed less favorable interactions (values between 24.26 and -45.50 kcal mol-1). In vitro analyses evaluated the biodegradation of PUs: Impranil® and PCLMDI; this latter showed high binding energy with this polyurethanase in silico. The biodegradation of Impranil® by S. liquefaciens and its partially purified polyurethanase was confirmed in agar by forming a transparent halo. Impranil® disks inoculated with S. liquefaciens and incubated at 30 °C for six days showed rupture of the PU structure, possibly due to the formation of cracks visualized by scanning electron microscopy (SEM). PCLMDI films were also biodegraded by S. liquefaciens after 60 days of incubation, with the formation of pores and cracks visualized by SEM. The biodegradation may have occurred due to the action of polyurethanase produced by this bacterium. This work provides essential information on the potential of S. liquefaciens to biodegrade PUs through in silico analyses combined with in vitro analyses.


Assuntos
Serratia liquefaciens , Humanos , Serratia liquefaciens/metabolismo , Poliuretanos/química , Simulação de Acoplamento Molecular , Biodegradação Ambiental , Supuração
12.
Rev. bras. ortop ; 58(3): 471-477, May-June 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1449833

RESUMO

Abstract Objective To translate and culturally adapt the Long Head of Biceps Tendon (LHB) score into Brazilian Portuguese. Methods The process involved translations by professionals fluent in the target language, followed by independent back translations. Next, a committee compared the original and translated versions, pretested the final version, and concluded it. Results We translated and adapted the questionnaire according to the proposed methodology. In the first version in Portuguese (VP1) there was divergence regarding the translation of twelve terms. Compared to the original version, the back translation of VP1 presented eight diverging terms. A committee prepared a second version in Portuguese (VP2) and applied it to a pretest group consisting of 30 participants. Finally, we conceived the third version in Portuguese, called LHB-pt. Conclusion The translation and cultural adaptation into Brazilian Portuguese of the LBH score was successfully accomplished.


Assuntos
Tenodese , Tenotomia
13.
Artigo em Inglês | MEDLINE | ID: mdl-37047988

RESUMO

Atmospheric data are collected by researchers every day. Campaigns such as GOAmazon 2014/2015 and the Amazon Tall Tower Observatory collect essential data on aerosols, gases, cloud properties, and meteorological parameters in the Brazilian Amazon basin. These data products provide insights and essential information for analyzing and predicting natural processes. However, in Brazil, it is estimated that more than 80% of the scientific data collected are not published due to the lack of web portals that collect and store these data. This makes it difficult, or even impossible, to access and integrate the data, which can result in the loss of significant amounts of information and significantly affect the understanding of the overall data. To address this problem, we propose a data portal architecture and open data deployment that enable Big Data processing, human interaction, and download-oriented approaches with tools that help users catalog, publish and visualize atmospheric data. Thus, we describe the architecture developed, based on the experience of the Atmospheric Radiation Measurement Data Center, which incorporates the principles of FAIR, the infrastructure and content management system for managing scientific data. The portal partial results were tested with environmental data from contaminated areas at the University of São Paulo. Overall, this data portal creates more shared knowledge about atmospheric processes by providing users with access to open environmental data.


Assuntos
Publicações , Editoração , Humanos , Brasil , Aerossóis
14.
Ecancermedicalscience ; 17: 1523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113718

RESUMO

Background: Prognostic and predictive markers in metastatic pheochromocytoma and paraganglioma (mPPGL) are unknown. We aimed to evaluate epidemiology of mPPGL, and prognostic factors of overall survival (OS) and predictive markers of treatment duration with first-line chemotherapy (TD1L). Patients and methods: Retrospective multicentre study of adult patients with mPPGL treated in Latin American centres between 1982 and 2021. Results: Fifty-eight patients were included: 53.4% were female, median age at diagnosis of mPPGL was 36 years and 12.1% had a family history of PPGL. The primary site was adrenal, non-adrenal infradiaphragmatic and supradiaphragmatic in 37.9%, 34.5% and 27.6%, respectively. 65.5% had a functioning tumour and 62.1% had metachronous metastases. Positive uptakes were found in 32 (55.2%) 68Gallium positron emission tomography (PET/CT), 27 (46.6%) 2-deoxy-2-[fluorine-18]fluoro-D-glucose PET/CT and 37 (63.8%) of 131Iodine-metaiodobenzylguanidine (MIBG) tests. Twenty-three (40%) patients received first-line chemotherapy, with cyclophosphamide, vincristine and dacarbazine used in 12 (52%) of patients. At a median follow-up of 62.8 months, median TD1L was 12.8 months. Either functional exams, tumour functionality, pathological characteristics or primary tumour location were significantly associated with response or survival. Yet, negative MIBG, Ki67 ≥ 10%, infradiaphragmatic location and functional tumours were associated with numerically inferior OS. Conclusions: In patients with mPPGL, prognostic and predictive factors to chemotherapy are still unknown, but negative MIBG uptake, Ki67 ≥ 10%, infradiaphragmatic location and functional tumours were numerically linked to worse OS. Our results should be further validated in larger and independent cohorts.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36901418

RESUMO

Sustainable Engineering education must provide cyber-physical and distributed systems competencies, such as the Internet of Things (IoT), to contribute to the Sustainable Development Goals (SDG). The COVID-19 pandemic caused profound impacts arising from a traditional on-site teaching model rupture and demanded distance learning for engineering students. In this context, we considered the following Research Questions (RQ): How can Project Based Learning (PjBL) be applied in hardware and software courses from the Engineering curriculum to foster practical activities during the COVID-19 pandemic? Is the student performance in the fully remote offering comparable to the face-to-face offering? (RQ1); Which Sustainable Development Goals are related to the Engineering students' project themes? (RQ2). Regarding RQ1, we present how PjBL was applied in first-, third- and fifth-year Computer Engineering Courses to support 31 projects of 81 future engineers during the COVID-19 pandemic. Student grades in a Software Engineering course indicate no relevant differences between student performance in remote and face-to-face offerings. Regarding RQ2, most Computer Engineering students from the Polytechnic School of the University of São Paulo in 2020 and 2021 decided to create projects related to SDG 3-Good Health and Well-being, SDG 8-Decent Work and Economic Growth and SDG 11-Sustainable Cities and Communities. Most projects were related to health and well-being, which was an expected behavior according to how health issues were brought into highlight during the pandemic.


Assuntos
COVID-19 , Humanos , Pandemias , Estudantes , Cidades , Redes de Comunicação de Computadores
16.
Heliyon ; 9(3): e14152, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36923901

RESUMO

The expression of many virulence genes in bacteria is regulated by quorum sensing (QS), and the inhibition of this mechanism has been intensely investigated. N-acetylcysteine (NAC) has good antibacterial activity and is able to interfere with biofilm-related respiratory infections, but little is known whether this compound has an effect on bacterial QS communication. This work aimed to evaluate the potential of NAC as a QS inhibitor (QSI) in Pseudomonas aeruginosa PAO1 through in silico and in vitro analyses, as well as in combination with the antibiotic tobramycin. Initially, a molecular docking analysis was performed between the QS regulatory proteins, LasR and RhlR, of P. aeruginosa with NAC, 3-oxo-C12-HSL, C4-HSL, and furanone C30. The NAC sub-inhibitory concentration was determined by growth curves. Then, we performed in vitro tests using the QS reporter strains P. aeruginosa lasB-gfp and rhlA-gfp, as well as the expression of QS-related phenotypes. Finally, the synergistic effect of NAC with the antibiotic tobramycin was calculated by fractional inhibitory concentrations index (FICi) and investigated against bacterial growth, pigment production, and biofilm formation. In the molecular docking study, NAC bound to LasR and RhlR proteins in a similar manner to the AHL cognate, suggesting that it may be able to bind to QS receptor proteins in vivo. In the biosensor assay, the GFP signal was turned down in the presence of NAC at 1000, 500, 250, and 125 µM for lasB-gfp and rhlA-gfp (p < 0.05), suggesting a QS inhibitory effect. Pyocyanin and rhamnolipids decreased (p < 0.05) up to 34 and 37%, respectively, in the presence of NAC at 125 µM. Swarming and swimming motilities were inhibited (p < 0.05) by NAC at 250 to 10000 µM. Additionally, 2500 and 10000 µM of NAC reduced biofilm formation. NAC-tobramycin combination showed synergistic effect with FICi of 0.8, and the best combination was 2500-1.07 µM, inhibiting biofilm formation up to 60%, besides reducing pyocyanin and pyoverdine production. Confocal microscopy images revealed a stronger, dense, and compact biofilm of P. aeruginosa PAO1 control, while the biofilm treated with NAC-tobramycin became thinner and more dispersed. Overall, NAC at low concentrations showed promising anti-QS properties against P. aeruginosa PAO1, adding to its already known effect as an antibacterial and antibiofilm agent.

17.
Braz J Microbiol ; 54(1): 239-258, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36701110

RESUMO

A novel bacterial strain, designated GeG2T, was isolated from soils of the native Cerrado, a highly biodiverse savanna-like Brazilian biome. 16S rRNA gene analysis of GeG2T revealed high sequence identity (100%) to the alphaproteobacterium Novosphingobium rosa; however, comparisons with N. rosa DSM 7285T showed several distinctive features, prompting a full characterization of the new strain in terms of physiology, morphology, and, ultimately, its genome. GeG2T cells were Gram-stain-negative bacilli, facultatively anaerobic, motile, positive for catalase and oxidase activities, and starch hydrolysis. Strain GeG2T presented planktonic-sessile dimorphism and cell aggregates surrounded by extracellular matrix and nanometric spherical structures were observed, suggesting the production of exopolysaccharides (EPS) and outer membrane vesicles (OMVs). Despite high 16S rDNA identity, strain GeG2T showed 90.38% average nucleotide identity and 42.60% digital DNA-DNA hybridization identity with N. rosa, below species threshold. Whole-genome assembly revealed four circular replicons: a 4.1 Mb chromosome, a 2.7 Mb extrachromosomal megareplicon, and two plasmids (212.7 and 68.6 kb). The megareplicon contains a few core genes and plasmid-type replication/maintenance systems, consistent with its classification as a chromid. Genome annotation shows a vast repertoire of carbohydrate-active enzymes and genes involved in the degradation of aromatic compounds, highlighting the biotechnological potential of the new isolate. Chemotaxonomic features, including polar lipid and fatty acid profiles, as well as physiological, molecular, and whole-genome comparisons showed significant differences between strain GeG2T and N. rosa, indicating that it represents a novel species, for which the name Novosphingobium terrae is proposed. The type strain is GeG2T (= CBMAI 2313T = CBAS 753 T).


Assuntos
Fosfolipídeos , Solo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Ubiquinona/química , Ubiquinona/genética , Filogenia , Técnicas de Tipagem Bacteriana , Microbiologia do Solo , Ácidos Graxos/química , Genômica
18.
J Proteomics ; 273: 104790, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36535623

RESUMO

Somatic embryogenesis (SE) involves modifications of cellular, biochemical, genetic, and epigenetic patterns. Our work investigated proteins as markers of embryogenic response and characterized the redox state of embryogenic cultures (EC) of Guadua chacoensis. We identified a total of 855 proteins; 129 were up- and 136 down-accumulated in EC as compared with non-embryogenic culture (NEC). Additionally, 37 and 22 proteins were identified as unique in EC and NEC, respectively. Heat-shock proteins as unique proteins and increased activity in Superoxide Dismutase and Guaiacol Peroxidase in EC suggest that the embryogenic response requires activation of the stress response mechanism. Ribosomal, translational, and glycolytic proteins in EC seem to be associated with protein synthesis and energy sources for embryo development, respectively. Accumulation of cell wall-related proteins, such as Arabinogalactan and Polygalacturonase inhibitors, and signaling transduction proteins, including Chitinase, Phospholipase, and Guanine nucleotide-binding proteins in EC seems to be associated with embryogenic response. Enhancement of H2O2 content in EC compared to NEC suggests a possible role as a secondary messenger in SE. Altogether, the present study identified marker proteins of embryogenic response in G. chacoensis and revealed the activation of ROS scavenging enzymes to assure cell redox homeostasis and SE responses. SIGNIFICANCE: Somatic embryogenesis is a promising technique for the propagation and conservation of bamboo species; however, this route has been the least understood and studied until now. This study corresponds to the first work approaching proteomics complemented with biochemical analyses in the somatic embryogenesis of bamboo, bringing robust and precise information that can improve our understanding of this complex morphogenetic route.


Assuntos
Antioxidantes , Poaceae , Proteômica/métodos , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/metabolismo , Desenvolvimento Embrionário , Técnicas de Embriogênese Somática de Plantas/métodos , Regulação da Expressão Gênica de Plantas
19.
Rev. bras. ciênc. esporte ; 45: e20230027, 2023.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1521682

RESUMO

RESUMO O presente artigo descreve experiências de um processo crítico que resulta na renovação de sentidos da Educação Física no Uruguai. Para tanto, realizou entrevistas com seis docentes do Instituto Superior de Educación Física da Universidad de la República. A partir das narrativas, discute dois planos de estudo da instituição e analisa a presença de literatura brasileira no ISEF, oportunidades para conhecer as transformações teórico-discursivas operadas no campo da Educação Física uruguaia.


ABSTRACT The article describes experiences of a critical process that results in the renewal of meanings of Physical Education in Uruguay. To delve into this, interviews were carried out with six professors from the Higher Institute of Physical Education of the University of the Republic. From the narratives, it discusses two study plans of the institution and analyzes the presence of Brazilian literature in ISEF, opportunities to get to know the theoretical-discursive transformations operated in the field of uruguayan Physical Education.


RESUMEN Este artículo describe experiencias de un proceso crítico que resulta en la renovación de los sentidos de la Educación Física en Uruguay. Para tanto, se realizaron entrevistas con seis docentes del Instituto Superior de Educación Física de la Universidad de la República. A partir de las narrativas, se discuten dos planes de estudio de la institución y se analiza la presencia de bibliografía brasileña en el ISEF, oportunidades para conocer las transformaciones teórico-discursivas operadas en el campo de la Educación Física uruguaya.

20.
Heliyon, v. 9, n. 3, e14152, mar. 2023
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4828

RESUMO

The expression of many virulence genes in bacteria is regulated by quorum sensing (QS), and the inhibition of this mechanism has been intensely investigated. N-acetylcysteine (NAC) has good antibacterial activity and is able to interfere with biofilm-related respiratory infections, but little is known whether this compound has an effect on bacterial QS communication. This work aimed to evaluate the potential of NAC as a QS inhibitor (QSI) in Pseudomonas aeruginosa PAO1 through in silico and in vitro analyses, as well as in combination with the antibiotic tobramycin. Initially, a molecular docking analysis was performed between the QS regulatory proteins, LasR and RhlR, of P. aeruginosa with NAC, 3-oxo-C12-HSL, C4-HSL, and furanone C30. The NAC sub-inhibitory concentration was determined by growth curves. Then, we performed in vitro tests using the QS reporter strains P. aeruginosa lasB-gfp and rhlA-gfp, as well as the expression of QS-related phenotypes. Finally, the synergistic effect of NAC with the antibiotic tobramycin was calculated by fractional inhibitory concentrations index (FICi) and investigated against bacterial growth, pigment production, and biofilm formation. In the molecular docking study, NAC bound to LasR and RhlR proteins in a similar manner to the AHL cognate, suggesting that it may be able to bind to QS receptor proteins in vivo. In the biosensor assay, the GFP signal was turned down in the presence of NAC at 1000, 500, 250, and 125 μM for lasB-gfp and rhlA-gfp (p < 0.05), suggesting a QS inhibitory effect. Pyocyanin and rhamnolipids decreased (p < 0.05) up to 34 and 37%, respectively, in the presence of NAC at 125 μM. Swarming and swimming motilities were inhibited (p < 0.05) by NAC at 250 to 10000 μM. Additionally, 2500 and 10000 μM of NAC reduced biofilm formation. NAC-tobramycin combination showed synergistic effect with FICi of 0.8, and the best combination was 2500–1.07 μM, inhibiting biofilm formation up to 60%, besides reducing pyocyanin and pyoverdine production. Confocal microscopy images revealed a stronger, dense, and compact biofilm of P. aeruginosa PAO1 control, while the biofilm treated with NAC-tobramycin became thinner and more dispersed. Overall, NAC at low concentrations showed promising anti-QS properties against P. aeruginosa PAO1, adding to its already known effect as an antibacterial and antibiofilm agent.

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