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1.
Anal Chem ; 96(12): 4764-4773, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38484023

RESUMO

Ancient peptides are remnants of early biochemistry that continue to play pivotal roles in current proteins. They are simple molecules yet complex enough to exhibit independent functions, being products of an evolved biochemistry at the interface of life and nonlife. Their adsorption to minerals may contribute to their stabilization and preservation over time. To investigate the feasibility of conserved peptide sequences and structures as target biomarkers for the search for life on Mars or other planetary bodies, we conducted a bioinformatics selection of well-conserved ancient peptides and produced polyclonal antibodies for their detection using fluorescence microarray immunoassays. Additionally, we explored how adsorbing peptides to Mars-representative minerals to form organomineral complexes could affect their immunological detection. The results demonstrated that the selected peptides exhibited autonomous folding, with some of them regaining their structure, even after denaturation. Furthermore, their cognate antibodies detected their conformational features regardless of amino acid sequences, thereby broadening the spectrum of target peptide sequences. While certain antibodies displayed unspecific binding to bare minerals, we validated that peptide-mineral complexes can be detected using sandwich immunoassays, as confirmed through desorption and competitive assays. Consequently, we conclude that the diversity of peptide sequences and structures suitable for use as target biomarkers in astrobiology can be constrained to a few well conserved sets, and they can be detected even if they are adsorbed in organomineral complexes.


Assuntos
Exobiologia , Marte , Exobiologia/métodos , Minerais , Sequência de Aminoácidos , Peptídeos , Anticorpos , Biomarcadores
2.
Nucleic Acids Res ; 50(22): 12938-12950, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36511856

RESUMO

Genetic interventions on microbiomes, for clinical or biotechnological purposes, remain challenging. Conjugation-based delivery of genetic cargo is still unspecific and limited by low conjugation rates. Here we report an approach to overcome these problems, based on a synthetic bacterial adhesion system. Mating assemblers consist on a synthetic adhesion formed by the expression on the surface of donor and target cells of specific nanobodies (Nb) and their cognate antigen (Ag). The Nb-Ag bridge increased 1-3 logs transfer of a variety of plasmids, especially in liquid media, confirming that cell-cell docking is a main determinant limiting mating efficiency. Synthetic cell-to-cell adhesion allows efficient conjugation to targeted recipients, enhancing delivery of desired genes to a predefined subset of prey species, or even specific pathogenic strains such as enterohemorrhagic Escherichia coli (EHEC), within a bacterial community. The synthetic conjugation enhancer presented here optimizes plasmid delivery by selecting the target hosts with high selectivity.


Assuntos
Conjugação Genética , Técnicas Genéticas , Microbiota , Adesão Celular , Conjugação Genética/fisiologia , Escherichia coli/genética , Escherichia coli/metabolismo , Plasmídeos/genética , Biotecnologia/métodos , Microbiota/genética
3.
Int J Psychiatry Clin Pract ; 27(1): 82-91, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35792729

RESUMO

OBJECTIVES: Aripiprazole is an antipsychotic with a partial agonism of dopamine D2 and D3 receptors. This differential mechanism implies a rigorous appraisal of the appropriate therapeutic strategies in certain situations. To answer currently unsolved clinical questions about the use of oral and long-acting injectable (LAI) aripiprazole, we present here an expert consensus from 12 Spanish psychiatrists and a pharmacologist with extensive experience in the use of this antipsychotic. METHODS: Through one face-to-face session and online collaboration, we reached consensus and established practical recommendations based on scientific evidence and clinical experience. We classified the available scientific literature according to SIGN system and attributed a level of evidence to each reviewed article. RESULTS: The recommendations were divided according to (i) chronological dimension (based on previous treatments, including patients naïve or not to antipsychotic treatment and maintenance regimen), and (ii) dimension related to therapeutic options, comprising switches to aripiprazole and the most used combinations with this antipsychotic. CONCLUSIONS: We recommend considering aripiprazole as first treatment option in the early stages of schizophrenia and in patients with affective symptoms and contemplating a switch to aripiprazole LAI in all candidate patients. Importantly, switches from other antipsychotics should consider previous antipsychotic history and exposure to aripiprazole. KEYPOINTSAripiprazole can be considered as first treatment option in early stages of schizophrenia and in patients with significant affective symptoms.Aripiprazole LAI shows better adherence than oral aripiprazole and could be considered in all candidate patients.Before switching to aripiprazole, detailed information about previous antipsychotic history should be gathered.Switch to aripiprazole should be managed differently for aripiprazole naïve and non-naïve patients.Rigorous and controlled studies on antipsychotics in real clinical practice should be carried out.


Assuntos
Antipsicóticos , Psiquiatria , Esquizofrenia , Humanos , Aripiprazol , Esquizofrenia/tratamento farmacológico , Antipsicóticos/efeitos adversos , Dopamina/uso terapêutico , Preparações de Ação Retardada
4.
PLoS Pathog ; 15(8): e1008031, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31465434

RESUMO

Enterohemorrhagic E. coli (EHEC) is a human intestinal pathogen that causes hemorrhagic colitis and hemolytic uremic syndrome. No vaccines or specific therapies are currently available to prevent or treat these infections. EHEC tightly attaches to the intestinal epithelium by injecting the intimin receptor Tir into the host cell via a type III secretion system (T3SS). In this project, we identified a camelid single domain antibody (nanobody), named TD4, that recognizes a conserved Tir epitope overlapping the binding site of its natural ligand intimin with high affinity and stability. We show that TD4 inhibits attachment of EHEC to cultured human HeLa cells by preventing Tir clustering by intimin, activation of downstream actin polymerization and pedestal formation. Furthermore, we demonstrate that TD4 significantly reduces EHEC adherence to human colonic mucosa in in vitro organ cultures. Altogether, these results suggest that nanobody-based therapies hold potential in the development of much needed treatment and prevention strategies against EHEC infection.


Assuntos
Aderência Bacteriana/fisiologia , Colo/metabolismo , Escherichia coli Êntero-Hemorrágica/fisiologia , Infecções por Escherichia coli/metabolismo , Proteínas de Escherichia coli/antagonistas & inibidores , Receptores de Superfície Celular/antagonistas & inibidores , Anticorpos de Domínio Único/farmacologia , Sequência de Aminoácidos , Animais , Aderência Bacteriana/efeitos dos fármacos , Sítios de Ligação , Camelus , Colo/microbiologia , Colo/patologia , Escherichia coli Êntero-Hemorrágica/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/patologia , Proteínas de Escherichia coli/imunologia , Proteínas de Escherichia coli/metabolismo , Células HeLa , Humanos , Receptores de Superfície Celular/imunologia , Receptores de Superfície Celular/metabolismo , Homologia de Sequência , Anticorpos de Domínio Único/imunologia
5.
Entropy (Basel) ; 23(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34945870

RESUMO

A model for a pumped thermal energy storage system is presented. It is based on a Brayton cycle working successively as a heat pump and a heat engine. All the main irreversibility sources expected in real plants are considered: external losses arising from the heat transfer between the working fluid and the thermal reservoirs, internal losses coming from pressure decays, and losses in the turbomachinery. Temperatures considered for the numerical analysis are adequate for solid thermal reservoirs, such as a packed bed. Special emphasis is paid to the combination of parameters and variables that lead to physically acceptable configurations. Maximum values of efficiencies, including round-trip efficiency, are obtained and analyzed, and optimal design intervals are provided. Round-trip efficiencies of around 0.4, or even larger, are predicted. The analysis indicates that the physical region, where the coupled system can operate, strongly depends on the irreversibility parameters. In this way, maximum values of power output, efficiency, round-trip efficiency, and pumped heat might lay outside the physical region. In that case, the upper values are considered. The sensitivity analysis of these maxima shows that changes in the expander/turbine and the efficiencies of the compressors affect the most with respect to a selected design point. In the case of the expander, these drops are mostly due to a decrease in the area of the physical operation region.

6.
Entropy (Basel) ; 23(6)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205259

RESUMO

The increase in the proportion of elderly in Europe brings with it certain challenges that society needs to address, such as custodial care. We propose a scalable, easily modulated and live assistive technology system, based on a comfortable smart footwear capable of detecting walking behaviour, in order to prevent possible health problems in the elderly, facilitating their urban life as independently and safety as possible. This brings with it the challenge of handling the large amounts of data generated, transmitting and pre-processing that information and analysing it with the aim of obtaining useful information in real/near-real time. This is the basis of information theory. This work presents a complete system aiming at elderly people that can detect different user behaviours/events (sitting, standing without imbalance, standing with imbalance, walking, running, tripping) through information acquired from 20 types of sensor measurements (16 piezoelectric pressure sensors, one accelerometer returning reading for the 3 axis and one temperature sensor) and warn the relatives about possible risks in near-real time. For the detection of these events, a hierarchical structure of cascading binary models is designed and applied using artificial neural network (ANN) algorithms and deep learning techniques. The best models are achieved with convolutional layered ANN and multilayer perceptrons. The overall event detection performance achieves an average accuracy and area under the ROC curve of 0.84 and 0.96, respectively.

7.
Curr Top Microbiol Immunol ; 416: 51-72, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30088147

RESUMO

Infection with enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC), enteroinvasive E. coli (EIEC) and Shigella relies on the elaboration of a type III secretion system (T3SS). Few strains also encode a second T3SS, named ETT2. Through the integration of coordinated intracellular and extracellular cues, the modular T3SS is assembled within the bacterial cell wall, as well as the plasma membrane of the host cell. As such, the T3SS serves as a conduit, allowing the chaperone-regulated translocation of effector proteins directly into the host cytosol to subvert eukaryotic cell processes. Recent technological advances revealed high structural resolution of the T3SS apparatus and how it could be exploited to treat enteric disease. This chapter summarises the current knowledge of the structure and function of the E. coli T3SSs.


Assuntos
Escherichia coli Êntero-Hemorrágica/metabolismo , Escherichia coli Êntero-Hemorrágica/patogenicidade , Escherichia coli Enteropatogênica/metabolismo , Escherichia coli Enteropatogênica/patogenicidade , Sistemas de Secreção Tipo III/metabolismo , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Humanos
8.
Microb Cell Fact ; 18(1): 47, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30857538

RESUMO

BACKGROUND: The hemolysin (Hly) secretion system of E. coli allows the one-step translocation of hemolysin A (HlyA) from the bacterial cytoplasm to the extracellular medium, without a periplasmic intermediate. In this work, we investigate whether the Hly secretion system of E. coli is competent to secrete a repertoire of functional single-domain VHH antibodies (nanobodies, Nbs), facilitating direct screening of VHH libraries and the purification of selected Nb from the extracellular medium. RESULTS: We employed a phagemid library of VHHs obtained by immunization of a dromedary with three protein antigens from enterohemorrhagic E. coli (EHEC), namely, the extracellular secreted protein A (EspA), the extracellular C-terminal region of Intimin (Int280), and the translocated intimin receptor middle domain (TirM). VHH clones binding each antigen were enriched and amplified by biopanning, and subsequently fused to the C-terminal secretion signal of HlyA to be expressed and secreted in a E. coli strain carrying the Hly export machinery (HlyB, HlyD and TolC). Individual E. coli clones were grown and induced in 96-well microtiter plates, and the supernatants of the producing cultures directly used in ELISA for detection of Nbs binding EspA, Int280 and TirM. A set of Nb sequences specifically binding each of these antigens were identified, indicating that the Hly system is able to secrete a diversity of functional Nbs. We performed thiol alkylation assays demonstrating that Nbs are correctly oxidized upon secretion, forming disulphide bonds between cysteine pairs despite the absence of a periplasmic intermediate. In addition, we show that the secreted Nb-HlyA fusions can be directly purified from the supernatant of E. coli cultures, avoiding cell lysis and in a single affinity chromatography step. CONCLUSIONS: Our data demonstrate the Hly secretion system of E. coli can be used as an expression platform for screening and purification of Nb binders from VHH repertories.


Assuntos
Meios de Cultura/análise , Escherichia coli/fisiologia , Proteínas Hemolisinas/metabolismo , Anticorpos de Domínio Único/isolamento & purificação , Transporte Biológico , Escherichia coli/imunologia
9.
Breast Cancer Res ; 15(6): R116, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24330716

RESUMO

INTRODUCTION: Aberrant turnover of the actin cytoskeleton is intimately associated with cancer cell migration and invasion. Frequently however, evidence is circumstantial, and a reliable assessment of the therapeutic significance of a gene product is offset by lack of inhibitors that target biologic properties of a protein, as most conventional drugs do, instead of the corresponding gene. Proteomic studies have demonstrated overexpression of CapG, a constituent of the actin cytoskeleton, in breast cancer. Indirect evidence suggests that CapG is involved in tumor cell dissemination and metastasis. In this study, we used llama-derived CapG single-domain antibodies or nanobodies in a breast cancer metastasis model to address whether inhibition of CapG activity holds therapeutic merit. METHODS: We raised single-domain antibodies (nanobodies) against human CapG and used these as intrabodies (immunomodulation) after lentiviral transduction of breast cancer cells. Functional characterization of nanobodies was performed to identify which biochemical properties of CapG are perturbed. Orthotopic and tail vein in vivo models of metastasis in nude mice were used to assess cancer cell spreading. RESULTS: With G-actin and F-actin binding assays, we identified a CapG nanobody that binds with nanomolar affinity to the first CapG domain. Consequently, CapG interaction with actin monomers or actin filaments is blocked. Intracellular delocalization experiments demonstrated that the nanobody interacts with CapG in the cytoplasmic environment. Expression of the nanobody in breast cancer cells restrained cell migration and Matrigel invasion. Notably, the nanobody prevented formation of lung metastatic lesions in orthotopic xenograft and tail-vein models of metastasis in immunodeficient mice. We showed that CapG nanobodies can be delivered into cancer cells by using bacteria harboring a type III protein secretion system (T3SS). CONCLUSIONS: CapG inhibition strongly reduces breast cancer metastasis. A nanobody-based approach offers a fast track for gauging the therapeutic merit of drug targets. Mapping of the nanobody-CapG interface may provide a platform for rational design of pharmacologic compounds.


Assuntos
Actinas/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Proteínas dos Microfilamentos/imunologia , Terapia de Alvo Molecular/métodos , Proteínas Nucleares/imunologia , Anticorpos de Domínio Único/farmacologia , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Escherichia coli/genética , Feminino , Humanos , Camundongos SCID , Proteínas dos Microfilamentos/genética , Proteínas Nucleares/genética , Estrutura Terciária de Proteína
10.
Q J Exp Psychol (Hove) ; : 17470218231208664, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37818945

RESUMO

Several studies have challenged the conflict adaptation account of cognitive control effects, suggesting that they are the result of learning/memory processes independent from control modulation. Some authors have suggested that the item-specific proportion congruent (ISPC) effect (i.e., the smaller congruency effect on items presented frequently in an incongruent combination) is driven by colour-word contingency learning (CL). However, it has recently been suggested that CL can be explained in terms of episodic retrieval of the response given to the last encounter with the same stimulus, with no role of associative learning. This study aims to analyse the independent role of CL and episodic retrieval on the ISPC effect. Experiment 1 showed no effect of control modulation and indicated that, when manipulated independently, learning-driven contingency is modulated by the episodic factor, but it remains significant. Experiments 2 and 3 extended the study of the interplay between learning and recency to the colour-word CL paradigm, finding larger contingency effects on colour words compared with neutral ones and replicating the interaction between CL and episodic retrieval from Experiment 1. Surprisingly, these two experiments also showed control modulation apart from contingency and recency effects in colour words. In sum, our study reveals that the ISPC effect results from the joint contribution of cognitive control, associative learning, and episodic effects.

11.
Sci Data ; 10(1): 402, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353567

RESUMO

Documentary climate data describe evidence of past climate arising from predominantly written historical documents such as diaries, chronicles, newspapers, or logbooks. Over the past decades, historians and climatologists have generated numerous document-based time series of local and regional climates. However, a global dataset of documentary climate time series has never been compiled, and documentary data are rarely used in large-scale climate reconstructions. Here, we present the first global multi-variable collection of documentary climate records. The dataset DOCU-CLIM comprises 621 time series (both published and hitherto unpublished) providing information on historical variations in temperature, precipitation, and wind regime. The series are evaluated by formulating proxy forward models (i.e., predicting the documentary observations from climate fields) in an overlapping period. Results show strong correlations, particularly for the temperature-sensitive series. Correlations are somewhat lower for precipitation-sensitive series. Overall, we ascribe considerable potential to documentary records as climate data, especially in regions and seasons not well represented by early instrumental data and palaeoclimate proxies.

12.
Q J Exp Psychol (Hove) ; 75(8): 1528-1540, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34666581

RESUMO

Recent research on the relation between learning and cognitive control has assumed that conflict modulates learning, either by increasing arousal and hence improving learning in high-conflict situations, or by inducing control, and hence inhibiting the processing of distracters and their eventual association with the imperative responses. We analyse whether the amount of conflict, manipulated through the proportion of congruency in a set of Stroop inducer trials, affects learning of contingencies established on diagnostic trials composed by neutral words associated with colour responses. The results reproduced the list-wide proportion of congruency effect on the inducer trials, and showed evidence of contingency learning on the diagnostic trials, but provided no indication that this learning was modulated by the level of conflict. Specific analyses conducted to control for the impact of episodic effects on the expression of learning indicated that contingency effects were not driven by the incremental processes that could be expected by associative learning, but rather they were due to the impact of the most recent trial involving the same distracter. Accordingly, these effects disappeared when tested selectively on trials that required a non-matching response with respect to the previous occurrence of the distracter. We interpret this result in the context of the debate on how learning and memory interact with the processes of cognitive control.


Assuntos
Conflito Psicológico , Aprendizagem , Nível de Alerta , Condicionamento Clássico , Humanos , Aprendizagem/fisiologia , Tempo de Reação/fisiologia , Teste de Stroop
13.
Trends Microbiol ; 30(6): 524-533, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34840074

RESUMO

Type III secretion system (T3SS) effectors are key virulence factors that underpin the infection strategy of many clinically important Gram-negative pathogens, including Salmonella enterica, Shigella spp., enteropathogenic and enterohemorrhagic Escherichia coli and their murine equivalent, Citrobacter rodentium. The cellular processes or proteins targeted by the effectors can be common to multiple pathogens or pathogen-specific. The main approach to understanding T3SS-mediated pathogenesis has been to determine the contribution of one effector at a time, with the aim of piecing together individual functions and unveiling infection mechanisms. However, in contrast to this prevailing approach, simultaneous deletion of multiple effectors revealed that they function as an interconnected network in vivo, uncovering effector codependency and context-dependent effector essentiality. This paradigm shift in T3SS biology is at the heart of this opinion article.


Assuntos
Escherichia coli Êntero-Hemorrágica , Proteínas de Escherichia coli , Salmonella enterica , Citrobacter rodentium/genética , Escherichia coli Êntero-Hemorrágica/genética , Proteínas de Escherichia coli/metabolismo , Salmonella enterica/metabolismo , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
14.
Biology (Basel) ; 12(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36671748

RESUMO

Sports performance in athletes can be limited by respiratory factors, so it is understandable to propose that inspiratory muscle training (IMT) can improve respiratory function and exercise performance. Power-Breathe® (PwB) is a sectorized respiratory muscle training tool that uses a resistive load to train IMT. There is currently a growing interest in respiratory muscle training, so we set out to systematically assess the effects of IMT with PwB on respiratory parameters and athletic performance in physically active, healthy adults. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, the Cochrane and PEDro scales to assess methodological quality, effect size using the Rosenthal formula, and the Cochrane tool for estimation of risk of bias, studies searchable in Medline, Web of Science, and Cochrane. In addition, for the performance of the meta-analysis, the documentation and quantification of the heterogeneity in each meta-analysis were directed through the Cochran's Q test and the I2 statistic; in addition, a publication bias analysis was performed using funnel plots. Of the total of 241 studies identified in the search, 11 studies for the systematic review and nine for the meta-analysis met the exclusion and/or inclusion criteria. IMT, with PwB, showed significant improvements in maximal inspiratory pressure (MIP) and substantial improvements in forced vital capacity (FVC) in the meta-analysis results. Also, sports performance was significantly increased by IMT with PwB. In conclusion, the use of PwB is an IMT tool that improves respiratory and sports performance.

15.
Methods Mol Biol ; 2291: 253-272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704757

RESUMO

Therapeutic antibodies (Abs) inhibiting bacterial adhesion to host epithelia are an attractive option to reduce the load of Shiga toxin-producing E. coli (STEC) in the intestine of the patient and also in the bovine reservoir, thereby minimizing the risk of STEC contamination in the food chain. Of particular interest are recombinant single-domain Ab fragments called nanobodies (Nbs) derived from the variable domain of camelid heavy chain-only antibodies (VHH). The outer membrane adhesin intimin and the translocated intimin receptor (Tir) are essential for the attachment of STEC to host epithelia. In addition, EspA filaments of the bacterial type III protein secretion system are needed for Tir translocation into the host cell. Given their importance for bacterial adhesion and colonization, we developed Nbs against intimin, Tir and EspA proteins of STEC serotype O157:H7. Here, we report the screening methods used to isolate inhibitory Nbs blocking intimin-Tir protein-protein interaction, actin-pedestal formation, and intimate adhesion of STEC to epithelial cells in vitro. First, we describe how VHH gene repertoires can be produced as Nbs secreted by E. coli using the α-hemolysin (HlyA) protein secretion system. Next, we report the methods for identification of inhibitors of intimin-Tir protein-protein interaction and of STEC intimate adhesion to HeLa cells in culture. These methods can be adapted for the screening of Nbs against different adhesin-receptor complexes to block the adhesion of other pathogens to host cells.


Assuntos
Adesinas Bacterianas/imunologia , Anticorpos Antibacterianos/imunologia , Aderência Bacteriana/imunologia , Células Epiteliais , Escherichia coli O157/imunologia , Proteínas de Escherichia coli/imunologia , Receptores de Superfície Celular/imunologia , Anticorpos de Domínio Único/imunologia , Animais , Bovinos , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Escherichia coli O157/patogenicidade , Humanos
16.
Artigo em Inglês | MEDLINE | ID: mdl-34206354

RESUMO

This systematic review and meta-analysis aim to provide scientific evidence regarding the effects of training on respiratory muscle training's impact with the PowerBreath®. A systematic analysis based on the PRISMA guides and a conducted research structured around the bases of Web of Science, Scopus, Medline/PubMed, SciELO y Cochrane Library Plus. Six articles published before January 2021 were included. The documentation and quantification of heterogeneity in every meta-analysis were directed through Cochran's Q test and the statistic I2; additionally, a biased publication analysis was made using funnel plots, whose asymmetry was quantified Egger's regression. The methodological quality was assessed through McMaster's. PowerBreath® administering a ≥ 15% resistive load of the maximum inspiratory pressure (PIM) achieves significant improvements (54%) in said pressure within 4 weeks of commencing the inspiratory muscle training. The maximal volume of oxygen (VO2max) considerable enhancements was achieved from the 6 weeks associated with the maximum inspiratory pressure ≥ 21.5% post inspiratory muscle training onwards. Conversely, a significant blood lactate concentration decrement occurred from the 4th week of inspiratory muscle training, after a maximum inspiratory pressure ≥ 6.8% increment. PowerBreath® is a useful device to stimulate sport performance and increase pulmonary function.


Assuntos
Desempenho Atlético , Exercícios Respiratórios , Pulmão , Músculos Respiratórios , Terapia Respiratória
17.
Artigo em Inglês | MEDLINE | ID: mdl-34444425

RESUMO

The purpose of the study was to build a predictive model for estimating the risk of ICU admission or mortality among patients hospitalized with COVID-19 and provide a user-friendly tool to assist clinicians in the decision-making process. The study cohort comprised 3623 patients with confirmed COVID-19 who were hospitalized in the SALUD hospital network of Aragon (Spain), which includes 23 hospitals, between February 2020 and January 2021, a period that includes several pandemic waves. Up to 165 variables were analysed, including demographics, comorbidity, chronic drugs, vital signs, and laboratory data. To build the predictive models, different techniques and machine learning (ML) algorithms were explored: multilayer perceptron, random forest, and extreme gradient boosting (XGBoost). A reduction dimensionality procedure was used to minimize the features to 20, ensuring feasible use of the tool in practice. Our model was validated both internally and externally. We also assessed its calibration and provide an analysis of the optimal cut-off points depending on the metric to be optimized. The best performing algorithm was XGBoost. The final model achieved good discrimination for the external validation set (AUC = 0.821, 95% CI 0.787-0.854) and accurate calibration (slope = 1, intercept = -0.12). A cut-off of 0.4 provides a sensitivity and specificity of 0.71 and 0.78, respectively. In conclusion, we built a risk prediction model from a large amount of data from several pandemic waves, which had good calibration and discrimination ability. We also created a user-friendly web application that can aid rapid decision-making in clinical practice.


Assuntos
COVID-19 , Algoritmos , Humanos , Unidades de Terapia Intensiva , Aprendizado de Máquina , Estudos Retrospectivos , SARS-CoV-2
18.
Sci Rep ; 11(1): 18844, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34552127

RESUMO

Comparing pandemic waves could aid in understanding the evolution of COVID-19. The objective of the present study was to compare the characteristics and outcomes of patients hospitalized for COVID-19 in different pandemic waves in terms of severity and mortality. We performed an observational retrospective cohort study of 5,220 patients hospitalized with SARS-CoV-2 infection from February to September 2020 in Aragon, Spain. We compared ICU admissions and 30-day mortality, clinical characteristics, and risk factors of the first and second waves of COVID-19. The SARS-CoV-2 genome was also analyzed in 236 samples. Patients in the first wave (n = 2,547) were older (median age 74 years [IQR 60-86] vs. 70 years [53-85]; p < 0.001) and had worse clinical and analytical parameters related to severe COVID-19 than patients in the second wave (n = 2,673). The probability of ICU admission at 30 days was 16% and 10% (p < 0.001) and the cumulative 30-day mortality rates 38% and 32% in the first and second wave, respectively (p = 0.007). Survival differences were observed among patients aged 60 to 80 years. We also found some variability among death risk factors and the viral genome between waves. Therefore, the two analyzed COVID-19 pandemic waves were different in terms of disease severity and mortality.


Assuntos
COVID-19/epidemiologia , COVID-19/mortalidade , Genoma Viral/genética , Hospitalização/tendências , SARS-CoV-2/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/sangue , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Unidades de Terapia Intensiva/estatística & dados numéricos , Unidades de Terapia Intensiva/tendências , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pandemias/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Espanha , Adulto Jovem
19.
Microb Biotechnol ; 14(3): 1228-1236, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33929101

RESUMO

The surge of SARS-CoV-2 has challenged health systems worldwide and efficient tests to detect viral particles, as well as antibodies generated against them, are needed. Specificity, sensitivity, promptness or scalability are the main parameters to estimate the final performance, but rarely all of them match in a single test. We have developed SCOVAM, a protein microarray with several viral antigens (spike, nucleocapsid, main protease Nsp5) as capturing probes in a fluorescence immunoassay for COVID-19 serological testing. SCOVAM depicts IgG and IgM antibody responses against each of these proteins of 22 individuals in a single microscope slide. It detects specific IgM (0.094 µg ml-1 ) and IgG (~0.017 µg ml-1 ) and is scalable and cost-effective. We validated SCOVAM by comparing with a widely used chemiluminescent commercial serological test (n = 742). SCOVAM showed twice the sensitivity and allowed following seroconversion in a single assay. By analysing the prevalence 4 months later in a subset of 76 positive sera, we still detected 93.42% of positives, almost doubling the detection of the commercial assay. The higher sensitivity of SCOVAM is especially relevant to screen sera for convalescent plasma-based treatments, high-throughput antibody response monitoring after vaccination or evaluation of vaccine efficiency.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , COVID-19/terapia , Teste Sorológico para COVID-19 , Humanos , Imunização Passiva , Imunoglobulina G , Imunoglobulina M , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus , Soroterapia para COVID-19
20.
Science ; 371(6534)2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33707240

RESUMO

Infections with many Gram-negative pathogens, including Escherichia coli, Salmonella, Shigella, and Yersinia, rely on type III secretion system (T3SS) effectors. We hypothesized that while hijacking processes within mammalian cells, the effectors operate as a robust network that can tolerate substantial contractions. This was tested in vivo using the mouse pathogen Citrobacter rodentium (encoding 31 effectors). Sequential gene deletions showed that effector essentiality for infection was context dependent and that the network could tolerate 60% contraction while maintaining pathogenicity. Despite inducing very different colonic cytokine profiles (e.g., interleukin-22, interleukin-17, interferon-γ, or granulocyte-macrophage colony-stimulating factor), different networks induced protective immunity. Using data from >100 distinct mutant combinations, we built and trained a machine learning model able to predict colonization outcomes, which were confirmed experimentally. Furthermore, reproducing the human-restricted enteropathogenic E. coli effector repertoire in C. rodentium was not sufficient for efficient colonization, which implicates effector networks in host adaptation. These results unveil the extreme robustness of both T3SS effector networks and host responses.


Assuntos
Proteínas de Bactérias/metabolismo , Citrobacter rodentium/patogenicidade , Infecções por Enterobacteriaceae/microbiologia , Redes e Vias Metabólicas , Sistemas de Secreção Tipo III/metabolismo , Animais , Proteínas de Bactérias/genética , Citrobacter rodentium/genética , Infecções por Enterobacteriaceae/imunologia , Feminino , Deleção de Genes , Imunidade , Camundongos , Camundongos Endogâmicos C57BL , Proteólise , Sistemas de Secreção Tipo III/genética , Virulência
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