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1.
BMC Gastroenterol ; 23(1): 229, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400812

RESUMO

BACKGROUND: Probiotics are effective for treating acute infectious diarrhoea caused by bacteria, but there are inconsistent results for the effectiveness of probiotics for diarrhoea caused by viruses. In this article we want to determine whether Sb supplementation has an effect on acute inflammatory viral diarrhoea diagnosed with the multiplex panel PCR test. The aim of this study was to evaluate the efficacy of Saccharomyces boulardii (Sb) as a treatment in patients diagnosed with viral acute diarrhoea. METHODS: From February 2021 to December 2021, 46 patients with a confirmed diagnosis of viral acute diarrhoea diagnosed with the polymerase chain reaction multiplex assay were enrolled in a double-blind, randomized placebo-controlled trial. Patients received paracetamol 500 mg as a standard analgesic and 200 mg of Trimebutine as an antispasmodic treatment plus 600 mg of Sb (n = 23, 1 × 109/100 mL Colony forming unit) or a placebo (n = 23) orally once daily for eight days. The improvement in and severity of symptoms were measured using a symptom diary, the Patient Global Impression and the Patient Global Impression of Change scales (days 4 and 8), both answered and recorded by the patient. RESULTS: Of the 46 patients who completed treatment, 24 (52%) were men and 22 (48%) were women. The average age was 35.6 ± 12.28 years (range 18 to 61 years). The average duration of the evolution of illness at the time of diagnosis was 0.85 ± 0.73 days (maximum 2 days). On day 4 after the diagnosis, 20% reported pain and 2% reported fever, but on day 8, no patient reported pain or fever. On day 4, 70% of patients in the Sb group and 26% in the placebo group reported improvement (P = 0.03), based on the Patients' Global Impression of Change scale, which assesses patient's rating of overall improvement. These findings suggest that 3 to 4 days of treatment with Sb helped to improve symptoms of diarrhoea caused by a virus. CONCLUSION: Treatment with Sb on acute inflammatory diarrhoea of viral aetiology shows no changes regarding the severity of the symptoms; nevertheless, it seems to impact improvement positively. TRIAL REGISTRATION: 22CEI00320171130 dated on 16/12/2020, NCT05226052 dated on 07/02/2022.


Assuntos
Enterite , Probióticos , Saccharomyces boulardii , Saccharomyces , Masculino , Humanos , Adulto , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Resultado do Tratamento , Saccharomyces cerevisiae , Diarreia/terapia , Diarreia/microbiologia , Probióticos/uso terapêutico , Método Duplo-Cego
2.
Micromachines (Basel) ; 13(12)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36557539

RESUMO

Population growth increases the challenge of meeting basic human needs, such as water, a limited resource. Consumption habits and water pollution have compromised natural resources to unsustainable levels. Sustainable effluent treatment practices, such as decentralized systems focused on energy, nutrients, and water recovery, have attracted the attention of the scientific community. Human urine (HU) is a physiological liquid waste whose main component is water (~95%). HU has a significant amount of nutrients, such as N, P, K, and organic matter, which are usually lacking in fecal coliforms. Therefore, the possibility exists of recovering nutrients and energy from HU using sustainable and non-sustainable technologies. Treating HU in bioelectrochemical systems (BES) is a novel alternative to obtaining byproducts from this effluent more sustainably than in electrochemical systems. Microbial fuel cells (MFCs) are an interesting example, contributing to HU revalorization from unwanted waste into a valuable resource of nutrients, energy, and water. Even when urine-operated MFCs have not generated attractive potential outputs or produced considerable amounts of bioelectricity, this review emphasizes HU advantages as nutrients or water sources. The aim of this review was to analyze the current development of BES for HU treatment based on the water circular economy, discussing challenges and perspectives researchers might encounter.

3.
Membranes (Basel) ; 11(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34677504

RESUMO

Microbial fuel cells (MFCs) are electrochemical devices focused on bioenergy generation and organic matter removal carried out by microorganisms under anoxic environments. In these types of systems, the anodic oxidation reaction is catalyzed by anaerobic microorganisms, while the cathodic reduction reaction can be carried out biotically or abiotically. Membranes as separators in MFCs are the primary requirements for optimal electrochemical and microbiological performance. MFC configuration and operation are similar to those of proton-exchange membrane fuel cells (PEMFCs)-both having at least one anode and one cathode split by a membrane or separator. The Nafion® 117 (NF-117) membrane, made from perfluorosulfonic acid, is a membrane used as a separator in PEMFCs. By analogy of the operation between electrochemical systems and MFCs, NF-117 membranes have been widely used as separators in MFCs. The main disadvantage of this type of membrane is its high cost; membranes in MFCs can represent up to 60% of the MFC's total cost. This is one of the challenges in scaling up MFCs: finding alternative membranes or separators with low cost and good electrochemical characteristics. The aim of this work is to critically review state-of-the-art membranes and separators used in MFCs. The scope of this review includes: (i) membrane functions in MFCs, (ii) most-used membranes, (iii) membrane cost and efficiency, and (iv) membrane-less MFCs. Currently, there are at least 20 different membranes or separators proposed and evaluated for MFCs, from basic salt bridges to advanced synthetic polymer-based membranes, including ceramic and unconventional separator materials. Studies focusing on either low cost or the use of natural polymers for proton-exchange membranes (PEM) are still scarce. Alternatively, in some works, MFCs have been operated without membranes; however, significant decrements in Coulombic efficiency were found. As the type of membrane affects the performance and total cost of MFCs, it is recommended that research efforts are increased in order to develop new, more economic membranes that exhibit favorable properties and allow for satisfactory cell performance at the same time. The current state of the art of membranes for MFCs addressed in this review will undoubtedly serve as a key insight for future research related to this topic.

4.
Neuroimage ; 202: 116091, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31415884

RESUMO

The Adolescent Brain Cognitive Development (ABCD) Study is an ongoing, nationwide study of the effects of environmental influences on behavioral and brain development in adolescents. The main objective of the study is to recruit and assess over eleven thousand 9-10-year-olds and follow them over the course of 10 years to characterize normative brain and cognitive development, the many factors that influence brain development, and the effects of those factors on mental health and other outcomes. The study employs state-of-the-art multimodal brain imaging, cognitive and clinical assessments, bioassays, and careful assessment of substance use, environment, psychopathological symptoms, and social functioning. The data is a resource of unprecedented scale and depth for studying typical and atypical development. The aim of this manuscript is to describe the baseline neuroimaging processing and subject-level analysis methods used by ABCD. Processing and analyses include modality-specific corrections for distortions and motion, brain segmentation and cortical surface reconstruction derived from structural magnetic resonance imaging (sMRI), analysis of brain microstructure using diffusion MRI (dMRI), task-related analysis of functional MRI (fMRI), and functional connectivity analysis of resting-state fMRI. This manuscript serves as a methodological reference for users of publicly shared neuroimaging data from the ABCD Study.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Imagem Multimodal , Adolescente , Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Processamento de Sinais Assistido por Computador
5.
Sci Rep ; 8(1): 17805, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30546034

RESUMO

The western corn rootworm (WCR) Diabrotica virgifera virgifera causes substantial damage in corn. Genetically modified (GM) plants expressing some Bacillus thuringiensis (Bt) insecticidal Cry proteins efficiently controlled this pest. However, changes in WCR susceptibility to these Bt traits have evolved and identification of insecticidal proteins with different modes of action against WCR is necessary. We show here for the first time that Cyt1Aa from Bt exhibits toxicity against WCR besides to the dipteran Aedes aegypti larvae. Cyt1Aa is a pore-forming toxin that shows no cross-resistance with mosquitocidal Cry toxins. We characterized different mutations in helix α-A from Cyt1Aa. Two mutants (A61C and A59C) exhibited reduced or absent hemolytic activity but retained toxicity to A. aegypti larvae, suggesting that insecticidal and hemolytic activities of Cyt1Aa are independent activities. These mutants were still able to form oligomers in synthetic lipid vesicles and to synergize Cry11Aa toxicity. Remarkably, mutant A61C showed a five-fold increase insecticidal activity against mosquito and almost 11-fold higher activity against WCR. Cyt1Aa A61C mutant was as potent in killing WCR that were selected for resistance to mCry3A as it was against unselected WCR indicating that this toxin could be a useful resistance management option in the control of WCR.


Assuntos
Bacillus thuringiensis , Proteínas de Bactérias , Besouros/crescimento & desenvolvimento , Endotoxinas , Proteínas Hemolisinas , Mutação de Sentido Incorreto , Controle Biológico de Vetores , Animais , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/toxicidade , Endotoxinas/genética , Endotoxinas/toxicidade , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade
6.
Peptides ; 53: 286-91, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24512949

RESUMO

Bacillus thuringiensis Cyt proteins are pore-forming toxins that have insecticidal activity mainly against dipteran insects. However, certain Cyt proteins have toxicity to some insect orders, but not toxicity of Cyt1Aa against lepidopteran larvae has been found. Insect specificity has been proposed to rely in specific binding to certain lipids on the brush border membrane of midgut cells since no protein receptors have been described so far. To determine the molecular basis of Cyt1Aa insect specificity we compared different steps of Cyt1Aa mode of action in a susceptible insect as the dipteran Aedes aegypti and also in the non-susceptible lepidopteran Manduca sexta. Our data shows that the lack toxicity of Cyt1Aa to M. sexta larvae does not rely on protoxin processing, membrane binding interaction, and oligomerization of Cyt1Aa since these steps were similar in the two insect species analyzed.


Assuntos
Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Peptídeo Hidrolases/metabolismo , Aedes/metabolismo , Animais , Toxinas de Bacillus thuringiensis , Concentração de Íons de Hidrogênio , Manduca/metabolismo , Microvilosidades/metabolismo , Ligação Proteica , Multimerização Proteica
7.
Environ Microbiol ; 15(11): 3030-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24112611

RESUMO

Bacillus thuringiensis produces insecticidal Cry and Cyt proteins that are toxic to different insect orders. In addition, Cyt toxins also display haemolytic activity. Both toxins are pore-forming proteins that form oligomeric structures that insert into the target membrane to lyse cells. Cyt toxins play an important role in mosquitocidal activity since they synergize Cry toxins and are able to overcome resistance to Cry toxins. Cry and Cyt toxins interact by specific epitopes, and this interaction is important to induce the synergistic activity observed. It was proposed that Cyt toxins do not interact with protein receptors but directly interacting with the specific midgut cell lipids. Here, we analysed if oligomerization and membrane insertion of Cyt1Aa are necessary steps to synergize Cry11Aa toxicity. We characterized Cyt1Aa helix α-C mutants that were affected in oligomerization, in membrane insertion and also in haemolytic and insecticidal activities. However, these mutants were still able to synergize Cry11Aa toxicity indicating these steps are independent events of Cyt1Aa synergistic activity. Furthermore, the data indicate that formation of stable Cyt1Aa-oligomeric structure is a key step for membrane insertion, haemolysis and insecticidal activity.


Assuntos
Aedes/efeitos dos fármacos , Proteínas de Bactérias/farmacologia , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Hemolíticos/farmacologia , Inseticidas/farmacologia , Animais , Bacillus thuringiensis , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Membrana Celular/química , Endotoxinas/química , Endotoxinas/genética , Proteínas Hemolisinas/química , Proteínas Hemolisinas/genética , Hemólise , Hemolíticos/química , Inseticidas/química , Larva/efeitos dos fármacos , Estrutura Secundária de Proteína
8.
Peptides ; 41: 87-93, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22691603

RESUMO

Bacillus thuringiensis bacteria produce different insecticidal proteins known as Cry and Cyt toxins. Among them the Cyt toxins represent a special and interesting group of proteins. Cyt toxins are able to affect insect midgut cells but also are able to increase the insecticidal damage of certain Cry toxins. Furthermore, the Cyt toxins are able to overcome resistance to Cry toxins in mosquitoes. There is an increasing potential for the use of Cyt toxins in insect control. However, we still need to learn more about its mechanism of action in order to define it at the molecular level. In this review we summarize important aspects of Cyt toxins produced by Bacillus thuringiensis, including current knowledge of their mechanism of action against mosquitoes and also we will present a primary sequence and structural comparison with related proteins found in other pathogenic bacteria and fungus that may indicate that Cyt toxins have been selected by several pathogenic organisms to exert their virulence phenotypes.


Assuntos
Bacillus thuringiensis , Proteínas de Bactérias/química , Endotoxinas/química , Proteínas Hemolisinas/química , Sequência de Aminoácidos , Toxinas de Bacillus thuringiensis , Modelos Moleculares , Dados de Sequência Molecular , Controle Biológico de Vetores , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Homologia Estrutural de Proteína
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