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1.
Nanotechnology ; 35(42)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39059417

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), etiological agent for the coronavirus disease 2019 (COVID-19), has resulted in over 775 million global infections. Early diagnosis remains pivotal for effective epidemiological surveillance despite the availability of vaccines. Antigen-based assays are advantageous for early COVID-19 detection due to their simplicity, cost-effectiveness, and suitability for point-of-care testing (PoCT). This study introduces a graphene field-effect transistor-based biosensor designed for high sensitivity and rapid response to the SARS-CoV-2 spike protein. By functionalizing graphene with monoclonal antibodies and applying short-duration gate voltage pulses, we achieve selective detection of the viral spike protein in human serum within 100 µs and at concentrations as low as 1 fg ml-1, equivalent to 8 antigen molecules perµl of blood. Furthermore, the biosensor estimates spike protein concentrations in serum from COVID-19 patients. Our platform demonstrates potential for next-generation PoCT antigen assays, promising fast and sensitive diagnostics for COVID-19 and other infectious diseases.


Assuntos
Técnicas Biossensoriais , COVID-19 , Grafite , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Transistores Eletrônicos , Glicoproteína da Espícula de Coronavírus/análise , Glicoproteína da Espícula de Coronavírus/imunologia , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Grafite/química , Humanos , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/imunologia , COVID-19/diagnóstico , COVID-19/sangue , COVID-19/virologia , Sensibilidade e Especificidade , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/química
2.
J Neuroeng Rehabil ; 21(1): 80, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755606

RESUMO

BACKGROUND: Individuals with a moderate-to-severe traumatic brain injury (m/sTBI), despite experiencing good locomotor recovery six months post-injury, face challenges in adapting their locomotion to the environment. They also present with altered cognitive functions, which may impact dual-task walking abilities. Whether they present collision avoidance strategies with moving pedestrians that are altered under dual-task conditions, however, remains unclear. This study aimed to compare between individuals with m/sTBI and age-matched control individuals: (1), the locomotor and cognitive costs associated with the concurrent performance of circumventing approaching virtual pedestrians (VRPs) while attending to an auditory-based cognitive task and; (2) gaze behaviour associated with the VRP circumvention task in single and dual-task conditions. METHODOLOGY: Twelve individuals with m/sTBI (age = 43.3 ± 9.5 yrs; >6 mo. post injury) and 12 healthy controls (CTLs) (age = 41.8 ± 8.3 yrs) were assessed while walking in a virtual subway station viewed in a head-mounted display. They performed a collision avoidance task with VRPs, as well as auditory-based cognitive tasks (pitch discrimination and auditory Stroop), both under single and dual-task conditions. Dual-task cost (DTC) for onset distance of trajectory deviation, minimum distance from the VRP, maximum lateral deviation, walking speed, gaze fixations and cognitive task accuracy were contrasted between groups using generalized estimating equations. RESULTS: In contrast to CTLs who showed locomotor DTCs only, individuals with m/sTBI displayed both locomotor and cognitive DTCs. While both groups walked slower under dual-task conditions, only individuals with m/sTBI failed to modify their onset distance of trajectory deviation and maintained smaller minimum distances and smaller maximum lateral deviation compared to single-task walking. Both groups showed shorter gaze fixations on the approaching VRP under dual-task conditions, but this reduction was less pronounced in the individuals with m/sTBI. A reduction in cognitive task accuracy under dual-task conditions was found in the m/sTBI group only. CONCLUSION: Individuals with m/sTBI present altered locomotor and gaze behaviours, as well as altered cognitive performances, when executing a collision avoidance task involving moving pedestrians in dual-task conditions. Potential mechanisms explaining those alterations are discussed. Present findings highlight the compromised complex walking abilities in individuals with m/sTBI who otherwise present a good locomotor recovery.


Assuntos
Lesões Encefálicas Traumáticas , Pedestres , Realidade Virtual , Humanos , Masculino , Adulto , Feminino , Lesões Encefálicas Traumáticas/reabilitação , Lesões Encefálicas Traumáticas/psicologia , Lesões Encefálicas Traumáticas/fisiopatologia , Pessoa de Meia-Idade , Desempenho Psicomotor/fisiologia , Caminhada/fisiologia , Cognição/fisiologia , Aprendizagem da Esquiva , Atenção/fisiologia
3.
BMC Microbiol ; 23(1): 364, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38008714

RESUMO

BACKGROUND: Probiotics have gained attention for their potential maintaining gut and immune homeostasis. They have been found to confer protection against pathogen colonization, possess immunomodulatory effects, enhance gut barrier functionality, and mitigate inflammation. However, a thorough understanding of the unique mechanisms of effects triggered by individual strains is necessary to optimize their therapeutic efficacy. Probiogenomics, involving high-throughput techniques, can help identify uncharacterized strains and aid in the rational selection of new probiotics. This study evaluates the potential of the Escherichia coli CEC15 strain as a probiotic through in silico, in vitro, and in vivo analyses, comparing it to the well-known probiotic reference E. coli Nissle 1917. Genomic analysis was conducted to identify traits with potential beneficial activity and to assess the safety of each strain (genomic islands, bacteriocin production, antibiotic resistance, production of proteins involved in host homeostasis, and proteins with adhesive properties). In vitro studies assessed survival in gastrointestinal simulated conditions and adhesion to cultured human intestinal cells. Safety was evaluated in BALB/c mice, monitoring the impact of E. coli consumption on clinical signs, intestinal architecture, intestinal permeability, and fecal microbiota. Additionally, the protective effects of both strains were assessed in a murine model of 5-FU-induced mucositis. RESULTS: CEC15 mitigates inflammation, reinforces intestinal barrier, and modulates intestinal microbiota. In silico analysis revealed fewer pathogenicity-related traits in CEC15, when compared to Nissle 1917, with fewer toxin-associated genes and no gene suggesting the production of colibactin (a genotoxic agent). Most predicted antibiotic-resistance genes were neither associated with actual resistance, nor with transposable elements. The genome of CEC15 strain encodes proteins related to stress tolerance and to adhesion, in line with its better survival during digestion and higher adhesion to intestinal cells, when compared to Nissle 1917. Moreover, CEC15 exhibited beneficial effects on mice and their intestinal microbiota, both in healthy animals and against 5FU-induced intestinal mucositis. CONCLUSIONS: These findings suggest that the CEC15 strain holds promise as a probiotic, as it could modulate the intestinal microbiota, providing immunomodulatory and anti-inflammatory effects, and reinforcing the intestinal barrier. These findings may have implications for the treatment of gastrointestinal disorders, particularly some forms of diarrhea.


Assuntos
Proteínas de Escherichia coli , Mucosite , Probióticos , Camundongos , Humanos , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Inflamação , Probióticos/uso terapêutico
4.
Arch Microbiol ; 205(2): 75, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36708387

RESUMO

Fungi of the genus Penicillium section Sclerotiora have as their main characteristic the presence of orange-pigmented mycelium, which is associated with sclerotiorin, a chlorinated secondary metabolite of the azaphilone subclass of polyketides. Sclerotiorin presents anti-diabetes, antioxidant, anti-inflammatory, anti-Alzheimer, antiviral, and antimicrobial activities, which has always attracted the attention of researchers worldwide. During our ongoing search for azaphilone-producing Amazonian fungi, the strain of Penicillium MMSRG-058 was isolated as an endophyte from the roots of Duguetia stelechantha and showed great capacity for producing sclerotiorin-like metabolites. Using multilocus phylogeny, this strain was identified as Penicillium meliponae. Moreover, based on the genome mining of this strain through the reverse approach, a cluster of putative biosynthetic genes (BGC) responsible for the biosynthesis of sclerotiorin-like metabolites (scl cluster) was identified. The knockout of the sclA (highly reducing PKS) and sclI (non-reducing PKS) genes resulted in mutants with loss of mycelial pigmentation and terminated the biosynthesis of sclerotiorin-like metabolites: geumsanol B, chlorogeumsanol B, 7-deacetylisochromophilone VI, isochromophilone VI, ochrephilone, isorotiorin, and sclerotiorin. Based on these results, a biosynthetic pathway was proposed considering the homology of BGC scl genes with the azaphilone BGCs that have already been functionally characterized.


Assuntos
Penicillium , Técnicas de Inativação de Genes , Penicillium/genética , Penicillium/metabolismo , Fungos/genética , Família Multigênica
5.
Microb Ecol ; 86(4): 2488-2501, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37326636

RESUMO

Biofilms are complex microecosystems with valuable ecological roles that can shelter a variety of microorganisms. Spirochetes from the genus Leptospira have been observed to form biofilms in vitro, in rural environments, and in the kidneys of reservoir rats. The genus Leptospira is composed of pathogenic and non-pathogenic species, and the description of new species is ongoing due to the advent of whole genome sequencing. Leptospires have increasingly been isolated from water and soil samples. To investigate the presence of Leptospira in environmental biofilms, we collected three distinct samples of biofilms formed in an urban setting with poor sanitation: Pau da Lima, in Salvador, Bahia, Brazil. All biofilm samples were negative for the presence of pathogenic leptospires via conventional PCR, but cultures containing saprophytic Leptospira were identified. Whole genomes were generated and analyzed for twenty isolates obtained from these biofilms. For species identification, we used digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analysis. The obtained isolates were classified into seven presumptive species from the saprophytic S1 clade. ANI and dDDH analysis suggest that three of those seven species were new. Classical phenotypic tests confirmed the novel isolated bacteria as saprophytic Leptospira. The isolates presented typical morphology and ultrastructure according to scanning electron microscopy and formed biofilms under in vitro conditions. Our data indicate that a diversity of saprophytic Leptospira species survive in the Brazilian poorly sanitized urban environment, in a biofilm lifestyle. We believe our results contribute to a better understanding of Leptospira biology and ecology, considering biofilms as natural environmental reservoirs for leptospires.


Assuntos
Leptospira , Leptospirose , Animais , Ratos , Leptospira/genética , Leptospirose/microbiologia , Brasil , Biofilmes , DNA
6.
Aging Clin Exp Res ; 35(11): 2623-2631, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804402

RESUMO

BACKGROUND: To promote optimal neuromuscular and cardiovascular gains in older adults, it seems crucial to investigate the effects of different combined training volumes in this population. Thus, the present study aimed to compare the effects of combined muscle power training (MPT) and endurance training (ET) with different volumes on functional and hemodynamic parameters in previously trained older adults. METHODS: Twenty-five older adults were randomly assigned to either the lower-volume group (LVG; n = 13) or the higher-volume group (HVG; n = 12). In the LVG, participants performed 1 set of 6 repetitions for each exercise, followed by 10 min of walking exercise. In the HVG, participants performed 2 sets of 6 repetitions for each exercise, followed by 20 min of walking exercise. Lift from the ventral decubitus position (LPDV), timed up-and-go (TUG), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were assessed before and after 8 weeks. RESULTS: Significant increases in LPDV test occurred in both groups after 8 weeks (p < 0.05). Additionally, significant improvements in TUG performance occurred in both groups from week 0 to week 8 (p < 0.05). However, no significant changes were observed between groups in functional parameters (p > 0.05). SBP and DBP remain unchanged (p > 0.05) in both groups over the experimental period. CONCLUSIONS: These findings indicate that lower-volume and higher-volume of combined MPT and ET promoted improvements in functional parameters. This study has an important practical application, as it indicates that regardless of the volume (lower or higher), comparable improvements are observed in functional parameters in previously trained older adults.


Assuntos
Treino Aeróbico , Treinamento Resistido , Humanos , Idoso , Exercício Físico/fisiologia , Caminhada/fisiologia , Pressão Sanguínea , Músculos , Força Muscular/fisiologia
7.
Clin Oral Investig ; 27(1): 377-385, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36220953

RESUMO

OBJECTIVE: Assess the prevalence of self-reported TMD symptoms and anxiety and check the quality of sleep and life during the distance learning period in university students at the University of Brasilia (UnB). MATERIALS AND METHODS: The participants were students from the Health Sciences College and Medicine College at UnB. Self-administered questionnaires were used to evaluate symptoms of TMD, quality of life, and sleep quality. One-way analysis of variance, followed by Bonferroni test, and Kruskal-Wallis test, followed by Dunn's test, were performed (P < 0.05). For qualitative data analysis, the chi-square test was applied (P < 0.05). RESULTS: Total 156 students were included; prevalence of TMD, anxiety, sleep disturbance, and poor sleep quality was 73.1%, 84%, 12.8%, and 62.8%, respectively. A greater prevalence of painful TMD was observed in students with severe anxiety (P = 0.007). Students with symptoms of painful TMD, severe anxiety, and sleep disorders had statistically worse quality of life. CONCLUSIONS: The implementation of distance learning in health courses to replace classroom teaching during the COVID-19 pandemic has impacted TMD prevalence, anxiety, quality of life, and sleep quality. CLINICAL RELEVANCE: Psychological factors are directly associated with TMD symptoms and quality of life, TMD conditions are related to quality of life as well. COVID-19 pandemic and the distance learning in health courses are new situations that can lead to a great impact on mental health and in consequence to TMD conditions and quality of life.


Assuntos
COVID-19 , Educação a Distância , Transtornos da Articulação Temporomandibular , Humanos , Autorrelato , Prevalência , Qualidade de Vida , Pandemias , COVID-19/complicações , COVID-19/epidemiologia , Transtornos da Articulação Temporomandibular/complicações , Inquéritos e Questionários , Dor
8.
Langmuir ; 34(23): 6903-6911, 2018 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-29792809

RESUMO

The association of organic molecules with two-dimensional (2D) materials, creating hybrid systems with mutual influences, constitutes an important testbed for both basic science self-assembly studies and perspective applications. Following this concept, in this work, we show a rich phenomenology that is involved in the interaction of thionine with graphene, leading to a hybrid material formed by well-organized self-assembled structures atop graphene. This composite system is investigated by atomic force microscopy, electric transport measurements, Raman spectroscopy, and first principles calculations, which show (1) an interesting time evolution of thionine self-assembled structures atop graphene; (2) a highly oriented final molecular assembly (in accordance with the underlying graphene surface symmetry); and (3) a strong n-type doping effect introduced in graphene by thionine. The nature of the thionine-substrate interaction is further analyzed in experiments using mica as a polar substrate. The present results may help pave the way to achieve tailored 2D material hybrid devices via properly chosen molecular self-assembly processes.

9.
Eur J Clin Pharmacol ; 74(8): 1001-1010, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29754216

RESUMO

PURPOSE: Participants' rights and safety must be guaranteed not only while a clinical trial is being conducted but also when a clinical trial finishes. The criteria for post-trial access to experimental drugs, however, are unclear in various countries. The objectives of this study were (i) to ascertain if there were regulations or guidelines related to patients' access to drugs after the end of clinical trials in the countries selected in the study and (ii) to analyze trends in post-trial access in countries classified by their level of economic development. METHODS: This study is a retrospective review. The data are from the records of clinical trials from 2014 registered in the World Health Organization's International Clinical Trials Registry Platform (ICTRP) database. RESULTS: Among the countries selected, provision of drugs post-trial is mandatory only in Argentina, Brazil, Chile, Finland, and Peru. The plans for post-trial access tend to be more present in low- and middle-income and upper middle-income countries, in comparison with high-income countries. Studies involving vulnerable populations are 2.53 times more likely to have plans for post-trial access than studies which do not. CONCLUSIONS: The guaranteeing of post-trial access remains mandatory in few countries. Considering that individuals seen as vulnerable have been included in clinical trials without plans for post-trial access, stakeholders must discuss the need to develop regulations mandating the guaranteeing of post-trial access in specified situations.


Assuntos
Ensaios Clínicos como Assunto/legislação & jurisprudência , Drogas em Investigação , Segurança do Paciente/legislação & jurisprudência , Ensaios Clínicos como Assunto/normas , Acessibilidade aos Serviços de Saúde/legislação & jurisprudência , Acessibilidade aos Serviços de Saúde/normas , Humanos , Legislação de Medicamentos , Sistema de Registros , Estudos Retrospectivos , Organização Mundial da Saúde
10.
J Basic Microbiol ; 58(2): 144-153, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29193198

RESUMO

Humicola grisea var. thermoidea (Hgvt) is a thermophilic ascomycete that produces lignocellulolytic enzymes and it is proposed for the conversion of agricultural residues into useful byproducts. Drugs that inhibit the DNA methyltransferases (DNMTs) activity are employed in epigenetic studies but nothing is known about a possible effect on the production of fungal enzymes. We evaluated the effect of 5-aza-2'-deoxycytidine (5-Aza; a chemical inhibitor of DNMTs activity) on the secreted enzyme activity and on the transcription of cellulase and xylanase genes from Hgvt grown in agricultural residues and in glucose. Upon cultivation on wheat bran (WB), the drug provoked an increase in the xylanase activity at 96 h. When Hgvt was grown in glucose (GLU), a repressor of Hgvt glycosyl hydrolase genes, 5-Aza led to increased transcript accumulation for the cellobiohydrolases and for the xyn2 xylanase genes. In WB, 5-Aza enhanced the expression of the transcription factor CreA gene. Growth on WB or GLU, in presence of 5-Aza, led to a significant increase in transcripts of the pH-response regulator PacC gene. To our knowledge, this is the first report on the effect of a DNMT inhibitor in the production of fungal plant cell wall degradation enzymes.


Assuntos
Azacitidina/análogos & derivados , Repressão Catabólica/efeitos dos fármacos , Celulase/biossíntese , Inibidores Enzimáticos/metabolismo , Enzimas/metabolismo , Sordariales/efeitos dos fármacos , Xilosidases/biossíntese , Azacitidina/metabolismo , Decitabina , Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Sordariales/crescimento & desenvolvimento , Triticum/metabolismo , Triticum/microbiologia
11.
Pain Med ; 18(1): 86-94, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27048345

RESUMO

Objective: The present study aimed to investigate if a new placebo device for interferential current (IFC) that delivers current during only the first 40 seconds of stimulation is effective at promoting adequate subject blinding. Methods: Seventy-five subjects were recruited and enrolled into three groups: active IFC, inactive placebo, and new placebo. Pressure pain threshold (PPT), cutaneous sensory threshold (CST), and pain intensity were measured before and after the intervention. After the final assessment, the subjects and the investigator who applied the current were asked about the type of stimulation administered. Results: None of the placebo forms studied resulted in significant changes to PPT, CST, or pain intensity. The subjects stimulated with active IFC at high intensities (> 17 mA) of stimulation showed higher PPT and CST and lower pain intensity than subjects stimulated at low intensities ( p < 0.03). The new placebo method blinded the investigator in 100% of cases of IFC and 60% of subjects stimulated, whereas for inactive placebo, the investigator was blinded at a rate of 0% and 34% of subjects. Conclusion: The new method of placebo IFC was effective for blinding of research investigators and most of the active IFC-treated subjects, promoting an appropriate placebo method.


Assuntos
Limiar da Dor , Placebos , Estimulação Elétrica Nervosa Transcutânea/métodos , Feminino , Humanos , Masculino , Adulto Jovem
12.
BMC Bioinformatics ; 17(Suppl 18): 456, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28105921

RESUMO

BACKGROUND: The evolution of Next-Generation Sequencing (NGS) has considerably reduced the cost per sequenced-base, allowing a significant rise of sequencing projects, mainly in prokaryotes. However, the range of available NGS platforms requires different strategies and software to correctly assemble genomes. Different strategies are necessary to properly complete an assembly project, in addition to the installation or modification of various software. This requires users to have significant expertise in these software and command line scripting experience on Unix platforms, besides possessing the basic expertise on methodologies and techniques for genome assembly. These difficulties often delay the complete genome assembly projects. RESULTS: In order to overcome this, we developed SIMBA (SImple Manager for Bacterial Assemblies), a freely available web tool that integrates several component tools for assembling and finishing bacterial genomes. SIMBA provides a friendly and intuitive user interface so bioinformaticians, even with low computational expertise, can work under a centralized administrative control system of assemblies managed by the assembly center head. SIMBA guides the users to execute assembly process through simple and interactive pages. SIMBA workflow was divided in three modules: (i) projects: allows a general vision of genome sequencing projects, in addition to data quality analysis and data format conversions; (ii) assemblies: allows de novo assemblies with the software Mira, Minia, Newbler and SPAdes, also assembly quality validations using QUAST software; and (iii) curation: presents methods to finishing assemblies through tools for scaffolding contigs and close gaps. We also presented a case study that validated the efficacy of SIMBA to manage bacterial assemblies projects sequenced using Ion Torrent PGM. CONCLUSION: Besides to be a web tool for genome assembly, SIMBA is a complete genome assemblies project management system, which can be useful for managing of several projects in laboratories. SIMBA source code is available to download and install in local webservers at http://ufmg-simba.sourceforge.net .


Assuntos
Bactérias/genética , Biologia Computacional/métodos , Mineração de Dados/métodos , Genoma Bacteriano , Bactérias/classificação , Bactérias/isolamento & purificação , Sequência de Bases , Mapeamento Cromossômico , Biologia Computacional/instrumentação , Sequenciamento de Nucleotídeos em Larga Escala , Internet , Análise de Sequência de DNA , Software
13.
BMC Genomics ; 17: 315, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27129708

RESUMO

BACKGROUND: Studies have detected mis-assemblies in genomes of the species Corynebacterium pseudotuberculosis. These new discover have been possible due to the evolution of the Next-Generation Sequencing platforms, which have provided sequencing with accuracy and reduced costs. In addition, the improving of techniques for construction of high accuracy genomic maps, for example, Whole-genome mapping (WGM) (OpGen Inc), have allow high-resolution assembly that can detect large rearrangements. RESULTS: In this work, we present the resequencing of Corynebacterium pseudotuberculosis strain 1002 (Cp1002). Cp1002 was the first strain of this species sequenced in Brazil, and its genome has been used as model for several studies in silico of caseous lymphadenitis disease. The sequencing was performed using the platform Ion PGM and fragment library (200 bp kit). A restriction map was constructed, using the technique of WGM with the enzyme KpnI. After the new assembly process, using WGM as scaffolder, we detected a large inversion with size bigger than one-half of genome. A specific analysis using BLAST and NR database shows that the inversion occurs between two homology RNA ribosomal regions. CONCLUSION: In conclusion, the results showed by WGM could be used to detect mismatches in assemblies, providing genomic maps with high resolution and allow assemblies with more accuracy and completeness. The new assembly of C. pseudotuberculosis was deposited in GenBank under the accession no. CP012837.


Assuntos
Mapeamento Cromossômico/métodos , Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano , Genômica/métodos , Óperon de RNAr/genética , DNA Bacteriano/genética , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA
14.
Curr Genomics ; 17(2): 145-52, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27226770

RESUMO

The ascomycete Trichoderma reesei is used for the production of plant cell wall-degrading enzymes in industrial scale. The interplay of the transactivator Xyr1 and the repressor Cre1 mainly regulates the expression of these enzymes. During induc-ing conditions, such as in the presence of sophorose, the transcription of the two major cellulase-encoding genes, cbh1 and cbh2, is activated as well as the expression of xyr1. In the presence of D-glucose carbon catabolite repression mediated by Cre1 takes place and the expression of Xyr1 and the plant cell wall-degrading enzymes is down-regulated. In this study we compare the chromatin status of xyr1, cbh1, and cbh2 promoters in the wild-type strain and the Cre1-deficient strain Rut-C30. Chromatin rearrangement occurs in the xyr1 promoter during induction on sophorose. Chromatin opening and protein-DNA interactions in the xyr1 promoter were detected especially in a region located 0.9 kb upstream the translation start co-don, which bears several putative Cre1-binding sites and a CCAAT-box. Moreover, the xyr1 promoter is overall more acces-sible in a cre1-truncated background, no matter which carbon source is present. This makes the xyr1 regulatory sequence a good target for promoter engineering aiming at the enhancement of cellulase production.

15.
BMC Genomics ; 16: 588, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26248555

RESUMO

BACKGROUND: Trichoderma reesei is used for industry-scale production of plant cell wall-degrading enzymes, in particular cellulases, but also xylanases. The expression of the encoding genes was so far primarily investigated on the level of transcriptional regulation by regulatory proteins. Otherwise, the impact of chromatin remodelling on gene expression received hardly any attention. In this study we aimed to learn if the chromatin status changes in context to the applied conditions (repressing/inducing), and if the presence or absence of the essential transactivator, the Xylanase regulator 1 (Xyr1), influences the chromatin packaging. RESULTS: Comparing the results of chromatin accessibility real-time PCR analyses and gene expression studies of the two prominent cellulase-encoding genes, cbh1 and cbh2, we found that the chromatin opens during sophorose-mediated induction compared to D-glucose-conferred repression. In the strain bearing a xyr1 deletion the sophorose mediated induction of gene expression is lost and the chromatin opening is strongly reduced. In all conditions the chromatin got denser when Xyr1 is absent. In the case of the xylanase-encoding genes, xyn1 and xyn2, the result was similar concerning the condition-specific response of the chromatin compaction. However, the difference in chromatin status provoked by the absence of Xyr1 is less pronounced. A more detailed investigation of the DNA accessibility in the cbh1 promoter showed that the deletion of xyr1 changed the in vivo footprinting pattern. In particular, we detected increased hypersensitivity on Xyr1-sites and stronger protection of Cre1-sites. Looking for the players directly causing the observed chromatin remodelling, a whole transcriptome shotgun sequencing revealed that 15 genes encoding putative chromatin remodelers are differentially expressed in response to the applied condition and two amongst them are differentially expressed in the absence of Xyr1. CONCLUSIONS: The regulation of xylanase and cellulase expression in T. reesei is not only restricted to the action of transcription factors but is clearly related to changes in the chromatin packaging. Both the applied condition and the presence of Xyr1 influence chromatin status.


Assuntos
Celulase/genética , Montagem e Desmontagem da Cromatina/genética , Cromatina/genética , Trichoderma/genética , Celulases/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Glucose/genética , Regiões Promotoras Genéticas/genética , Transativadores/genética , Transcrição Gênica/genética , Transcriptoma/genética
16.
J Hypertens ; 42(4): 735-742, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38441186

RESUMO

Previous studies have investigated the effects of different combined training programs involving traditional resistance training and aerobic exercise on hemodynamic parameters and arterial stiffness in older adults. However, little is known about the impact of power training combined with endurance training on these variables in hypertensive older adults. Therefore, this study aimed to investigate the effects of dynamic power training with elastic bands combined with endurance training on arterial stiffness and hemodynamic parameters in hypertensive older adults. Twenty-six participants were randomly assigned to the control group (CG; n = 13) and the intervention group (n = 13). IG participants performed power training with elastic bands combined with endurance training twice a week for 8 weeks. Pulse pressure, central pulse pressure, pulse wave velocity, SBP, DBP, central SBP, and central DBP were assessed before and after 8 weeks using the triple pulse wave velocity method. Pulse pressure, central pulse pressure, pulse wave velocity, SBP, DBP, central SBP, and central DBP significantly improved after 8 weeks of intervention (P < 0.05). These findings indicate that power training with elastic bands combined with endurance training reduces arterial stiffness and significantly improves hemodynamic parameters in older adults diagnosed with grade 1 hypertension. In addition, underscores the potential of this approach as a promising strategy for the management of hypertension in older adults.


Assuntos
Treino Aeróbico , Hipertensão , Treinamento Resistido , Humanos , Idoso , Análise de Onda de Pulso , Hipertensão/terapia , Pressão Sanguínea
17.
PeerJ ; 12: e16513, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313017

RESUMO

Background: Corynebacterium pseudotuberculosis is a zoonotic Gram-positive bacterial pathogen known to cause different diseases in many mammals, including lymph node abscesses in camels. Strains from biovars equi and ovis of C. pseudotuberculosis can infect camels. Comparative genomics could help to identify features related to host adaptation, and currently strain Cp162 from biovar equi is the only one from camel with a sequenced genome. Methods: In this work, we compared the quality of three genome assemblies of strain Cp162 that used data from the DNA sequencing platforms SOLiD v3 Plus, IonTorrent PGM, and Illumina HiSeq 2500 with an optical map and investigate the unique features of this strain. For this purpose, we applied comparative genomic analysis on the different Cp162 genome assembly versions and included other 129 genomes from the same species. Results: Since the first version of the genome, there was an increase of 88 Kbp and 121 protein-coding sequences, a decrease of pseudogenes from 139 to 53, and two inversions and one rearrangement corrected. We identified 30 virulence genes, none associated to the camel host, and the genes rpob2 and rbpA predicted to confer resistance to rifampin. In comparison to 129 genomes of the same species, strain Cp162 has four genes exclusively present, two of them code transposases and two truncated proteins, and the three exclusively absent genes lysG, NUDIX domain protein, and Hypothetical protein. All 130 genomes had the rifampin resistance genes rpob2 and rbpA. Our results found no unique gene that could be associated with tropism to camel host, and further studies should include more genomes and genome-wide association studies testing for genes and SNPs.


Assuntos
Corynebacterium pseudotuberculosis , Animais , Ovinos/genética , Corynebacterium pseudotuberculosis/genética , Camelus/genética , Genoma Bacteriano/genética , Estudo de Associação Genômica Ampla , Rifampina , Análise de Sequência de DNA
18.
Microorganisms ; 12(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39065132

RESUMO

Bacterial wilt, caused by Ralstonia solanacearum, is one of the main challenges for sustainable tomato production in the Amazon region. This study evaluated the potential of bacteria isolated from sediments of the Solimões and Negro rivers for the biocontrol of this disease. From 36 bacteria selected through in vitro antibiosis, three promising isolates were identified: Priestia aryabhattai RN 11, Streptomyces sp. RN 24, and Kitasatospora sp. SOL 195, which inhibited the growth of the phytopathogen by 100%, 87.62%, and 100%, respectively. These isolates also demonstrated the ability to produce extracellular enzymes and plant growth-promoting compounds, such as indole-3-acetic acid (IAA), siderophore, and ammonia. In plant assays, during both dry and rainy seasons, P. aryabhattai RN 11 reduced disease incidence by 40% and 90%, respectively, while promoting the growth of infected plants. Streptomyces sp. RN 24 and Kitasatospora sp. SOL 195 exhibited high survival rates (85-90%) and pathogen suppression in the soil (>90%), demonstrating their potential as biocontrol agents. This study highlights the potential of Amazonian bacteria as biocontrol agents against bacterial wilt, contributing to the development of sustainable management strategies for this important disease.

19.
J Bras Pneumol ; 50(1): e20230233, 2024.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38536982

RESUMO

Although lung cancer (LC) is one of the most common and lethal tumors, only 15% of patients are diagnosed at an early stage. Smoking is still responsible for more than 85% of cases. Lung cancer screening (LCS) with low-dose CT (LDCT) reduces LC-related mortality by 20%, and that reduction reaches 38% when LCS by LDCT is combined with smoking cessation. In the last decade, a number of countries have adopted population-based LCS as a public health recommendation. Albeit still incipient, discussion on this topic in Brazil is becoming increasingly broad and necessary. With the aim of increasing knowledge and stimulating debate on LCS, the Brazilian Society of Thoracic Surgery, the Brazilian Thoracic Association, and the Brazilian College of Radiology and Diagnostic Imaging convened a panel of experts to prepare recommendations for LCS in Brazil. The recommendations presented here were based on a narrative review of the literature, with an emphasis on large population-based studies, systematic reviews, and the recommendations of international guidelines, and were developed after extensive discussion by the panel of experts. The following topics were reviewed: reasons for screening; general considerations about smoking; epidemiology of LC; eligibility criteria; incidental findings; granulomatous lesions; probabilistic models; minimum requirements for LDCT; volumetric acquisition; risks of screening; minimum structure and role of the multidisciplinary team; practice according to the Lung CT Screening Reporting and Data System; costs versus benefits of screening; and future perspectives for LCS.


Assuntos
Neoplasias Pulmonares , Radiologia , Cirurgia Torácica , Humanos , Neoplasias Pulmonares/diagnóstico , Brasil/epidemiologia , Detecção Precoce de Câncer/métodos , Tomografia Computadorizada por Raios X/métodos , Programas de Rastreamento
20.
Polymers (Basel) ; 15(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139878

RESUMO

The conducted investigation encompassed the comprehensive integration of mechanical, environmental, chemical, and microstructural evaluations of a composite amalgamating sandy soil and a synthetic polymer at two distinct concentrations (2.5% and 5%) across multiple curing intervals (0, 1, 2, 4, 7, 15, 30, and 45 days). The studied soil originates from an environmentally significant protected area in Brazil. The implementation of mechanisms for soil improvement in the region must adhere to technical criteria without causing environmental harm. Direct shear testing was conducted, permeability was assessed, and microstructure analysis and XRD and XRF/EDX studies of both the soil and composites were conducted. It was observed that longer curing times yielded improved results in shear stress, friction angle, and cohesive intercept, with SP_5% exhibiting the highest values compared with the soil and SP_2.5%. Adding the polymeric solution to the soil contributed to cementation and cohesion gains in the substrate. Through microstructural characterization, the polymer's role as a cementing agent for the grains is evident, forming a film on the grains and binding them together. Based on the analyses and studies conducted in the research, it can be concluded that there is technical feasibility for applying the polymeric solution at both dosages in geotechnical projects.

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