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1.
J Public Econ ; 210: 104661, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35711616

RESUMO

This paper examines the impact of switching from paper to electronic invoicing on firm tax compliance and performance using quasi-experimental variation in the roll-out of VAT e-invoicing in Peru. We find that e-invoicing increases reported firm sales, purchases and VAT liabilities by over 5 percent in the first year after adoption. The impact is concentrated among small firms and sectors with higher rates of noncompliance, suggesting that e-invoicing enhances compliance by lowering compliance costs and strengthening deterrence. However, we also find that existing stocks of VAT credits were used to offset the reform's positive effects on VAT collection, suggesting that digital tools such as e-invoicing would need to be complemented by other reforms to improve revenue mobilization.

2.
Biochem Biophys Rep ; 29: 101193, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35128079

RESUMO

Immobilization of lipase from Burkholderia gladioli BRM58833 on octyl sepharose (OCT) resulted in catalysts with higher activity and stability. Following, strategies were studied to further stabilize and secure the enzyme to the support using functionalized polymers, like polyethylenimine (PEI) and aldehyde-dextran (DEXa), to cover the catalyst with layers at different combinations. Alternatively, the construction of a bifunctional layer was studied using methoxypolyethylene glycol amine (NH 2 -PEG) and glycine. The catalyst OCT-PEI-DEXa was the most thermostable, with a 263.8-fold increase in stability when compared to the control condition. When evaluated under alkaline conditions, OCT-DEXa-PEG 10 /Gly was the most stable, reaching stability 70.1 times greater than the control condition. Proportionally, the stabilization obtained for B. gladioli BRM58833 lipase was superior to that obtained for the commercial B. cepacia lipase. Preliminary results in the hydrolysis of fish oil demonstrated the potential of the coating technique with bifunctional polymers, resulting in a stable catalyst with greater catalytic capacity for the production of omega-3 PUFAs. According to the results obtained, it is possible to modulate B. gladioli BRM58833 lipase properties like stability and catalytic activity for enrichment of omega-3 fatty acids.

3.
Front Immunol ; 12: 779534, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970264

RESUMO

This is a case series study to evaluate immunological markers associated with schistosomiasis advanced fibrosis, including 69 patients from an endemic area from the State of Sergipe and from the Hepatology Service of the University Hospital in Sergipe, Brazil. Hepatic fibrosis was classified based on Niamey protocol for ultrasonography (US). Immune response to Schistosoma mansoni antigens was evaluated by stimulating peripheral blood mononuclear cells (PBMCs) from these patients with either adult worm (SWAP-10 µg/ml) or egg (SEA-10 µg/ml) antigens or purified protein derivative of turberculin (PPD-10 µg/ml) or phytohemagglutinin (PHA-1 µg/ml) for 72 h. The levels of IFN-γ, TNF-α, IL-5, IL-10, and IL-17 were measured in these supernatants by ELISA and IL-9 by Luminex. Single nucleotide polymorphisms in IL-17, IL10, and CD209 genes were genotyped using TaqMan probe by qPCR. Higher levels of IL-9, IL-10, and IL-17 were found in PBMC supernatants of patients with advanced hepatic fibrosis. Direct correlations were detected between IL-9 and IL-17 levels with US spleen sizes, portal vein diameters, and periportal thickening. The CD209 rs2287886 AG polymorphism patients produce higher IL-17 levels. Together, these data suggest a role of these cytokines in the immunopathogenesis of advanced fibrosis in human schistosomiasis.


Assuntos
Antígenos de Helmintos/imunologia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-9/metabolismo , Leucócitos Mononucleares/metabolismo , Cirrose Hepática/sangue , Schistosoma mansoni/imunologia , Esquistossomose mansoni/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores/metabolismo , Estudos de Casos e Controles , Moléculas de Adesão Celular/genética , Células Cultivadas , Criança , Feminino , Interações Hospedeiro-Parasita , Humanos , Interleucina-10/genética , Interleucina-17/genética , Lectinas Tipo C/genética , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/parasitologia , Cirrose Hepática/imunologia , Cirrose Hepática/parasitologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/genética , Schistosoma mansoni/patogenicidade , Esquistossomose mansoni/genética , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Adulto Jovem
4.
JAMA Netw Open ; 4(12): e2136128, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34870682

RESUMO

Importance: Immune checkpoint inhibitors (ICIs) have yielded conflicting results in hepatocellular carcinoma (HCC). The overall effect of ICIs compared with standard therapies in unresectable HCC requires more research. Objective: To estimate the efficacy and safety associated with ICIs compared with standard therapies in patients with unresectable HCC. Data Sources: PubMed, Cochrane Library, Web of Science, Latin American and Caribbean Health Sciences Literature, and American Society of Clinical Oncology and European Society of Medical Oncology meeting proceedings were systematically searched. Reference lists from studies selected by electronic searching were manually searched to identify additional relevant studies. The search included literature published or presented from February 2010 to February 2020. Study Selection: From December 2019 to February 2020, independent reviewers evaluated each database, scanning the title, abstract, and keywords of every record retrieved. Full articles were further assessed if the information given suggested that the study was a randomized clinical trial (RCT) comparing ICIs vs standard therapies in the treatment of unresectable HCC. Data Extraction and Synthesis: The full text of the resulting studies and extracted data were reviewed independently according to PRISMA guidelines. Summary hazard ratios (HRs) of overall survival (OS) and progression-free survival (PFS) were calculated by a random-effects model. The likelihood of ICIs being associated with overall response rate (ORR) and treatment-related adverse events (TRAEs) was expressed by odds ratios (ORs) using a random-effects model. Main Outcomes and Measures: The main outcomes were OS, PFS, ORR, and TRAEs. Results: Of 1836 studies yielded by the search, 3 were retained, totaling 1657 patients (985 treated with ICIs vs 672 receiving standard treatment). Two studies evaluated ICIs as monotherapy, and 1 study investigated the combination of ICIs with bevacizumab. Compared with standard therapies (sorafenib in first-line therapy or placebo in second-line therapy), ICIs were associated with significantly improved OS (HR, 0.75; 95% CI, 0.62-0.92; P = .006), PFS (HR, 0.74; 95% CI, 0.56-0.97; P = .03), and ORR (OR, 2.82; 95% CI 2.02-3.93; P < .001). The probability of grade 3 or 4 TRAEs was lower with ICIs than with sorafenib (OR, 0.44; 95% CI, 0.20-0.96; P = .04). Conclusions and Relevance: This meta-analysis found superior efficacy and safety associated with ICIs compared with standard therapies and highlights the survival benefit associated with the combination of antiangiogenic therapy with ICIs in first-line systemic therapy of unresectable HCC.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/efeitos adversos , Neoplasias Hepáticas/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Humanos , Neoplasias Hepáticas/mortalidade , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto , Sorafenibe/uso terapêutico , Resultado do Tratamento
5.
Antioxidants (Basel) ; 10(8)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34439494

RESUMO

Recovery in athletes is hampered by soreness and fatigue. Consequently, nonsteroidal anti-inflammatory drugs are used as an effective strategy to maintain high performance. However, impact of these drugs on adaptations induced by training remains unknown. This study assessed the effects of diclofenac administration (10 mg/kg/day) on rats subjected to an exhaustive test, after six weeks of swimming training. Over the course of 10 days, three repeated swimming bouts were performed, and diclofenac or saline were administered once a day. Trained animals exhibited higher muscle citrate synthase and lower plasma creatinine kinase activities as compared to sedentary animals, wherein diclofenac had no impact. Training increased time to exhaustion, however, diclofenac blunted this effect. It also impaired the increase in plasma and liver interleukin-6 levels. The trained group exhibited augmented catalase, glutathione peroxidase, and glutathione reductase activities, and a higher ratio of reduced-to-oxidized glutathione in the liver. However, diclofenac treatment blunted all these effects. Systems biology analysis revealed a close relationship between diclofenac and liver catalase. These results confirmed that regular exercise induces inflammation and oxidative stress, which are crucial for tissue adaptations. Altogether, diclofenac treatment might be helpful in preventing pain and inflammation, but its use severely affects performance and tissue adaptation.

6.
Dalton Trans ; 49(45): 16143-16153, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32239007

RESUMO

Cobalt complexes have been demonstrated to target zinc fingers, as shown by investigations of Doxovir, the trade name of the [CoIII(acacen)(2-Me-Imz)2]+ drug in clinical trials. Mechanistic studies indicate zinc finger disruption by metal coordination to His residues. Other than Doxovir, a few studies have investigated other ligands and geometries for cobalt complexes for zinc finger targeting. Tripod ligands demonstrated good zinc and cobalt chelation. In this manuscript, we report the ability of CoII and CoIII complexes of tri(2-pyridylmethyl)amine and N,N-di(2-pyridylmethyl)glycinate to disrupt zinc fingers. The results obtained by mass spectrometry and X-ray absorption spectroscopy demonstrate that the complexes were able to remove zinc from the zinc fingers. The product was oxidised apo-peptide. In contrast, the ligands themselves were able to remove zinc, and they did not promote oxidation, resulting in free Cys residues. Cobalt finger adducts were not detected for the complexes with tripod ligands unless they were coordinated to planar ligands such as salen or acacen. Studies of the interactions of cobalt complexes with amino acids demonstrated that tripod ligands promote the cysteine reaction, while the salen ligands promote histidine coordination, demonstrating a different mechanism of action. The results reported here are significant for better understanding and further design of zinc finger targeting compounds.


Assuntos
Cobalto/química , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Dedos de Zinco , Aminas/química , Ligantes , Modelos Moleculares
7.
Scand J Med Sci Sports ; 30(2): 264-271, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31618484

RESUMO

BACKGROUND: The use of NSAIDs has become a common practice to counteract the pro-inflammatory acute effects of exercise, in order to improve sports performance. The liver, due to its central role in energy metabolism, may be involved primarily in the process of ROS generation and consequently inflammation after exhaustive exercise. OBJECTIVE: To analyze the influence of diclofenac on the liver TLR4 pathway and time to exhaustion in rats submitted to repeated exhaustive swimming. METHODS: An exhaustive test was performed in order to mimic athletes' routine, and inflammatory status and oxidative stress markers were evaluated in the liver. Animals were divided into sedentary and exhaustion groups, with this last performing three exhaustive swimming bouts. At the same time, diclofenac or saline was pre-administered once a day for nine days. RESULTS: Data showed significantly increased COX-2, TLR4, and MyD88 protein content in the liver after exhaustive swimming bouts. The levels of pro-inflammatory cytokines also increased after exhaustive exercise, while these effects were attenuated in the group treated with diclofenac plus exhaustive swimming bouts. The anti-inflammatory modulation provoked by diclofenac treatment was associated with an increased time to exhaustion in the exercise bouts. The exhaustive exercise increased TBARS formation, but diclofenac treatment blunted this elevation, while GSH/GSSG ratios in both exhaustion-saline and exhaustion-diclofenac-treated groups were lower than in the sedentary-saline group. CONCLUSIONS: Our findings suggest that diclofenac may improve exercise performance and represent an effective tool to ameliorate the pro-inflammatory status in liver when associated with exhaustive exercise, and the liver may be a possible therapeutic target.


Assuntos
Diclofenaco/farmacologia , Condicionamento Físico Animal/fisiologia , Receptor 4 Toll-Like/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Inflamação , Fígado/metabolismo , Masculino , Fator 88 de Diferenciação Mieloide/metabolismo , Estresse Oxidativo , Distribuição Aleatória , Ratos , Ratos Wistar , Natação
8.
Dalton Trans ; 48(9): 2900-2916, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30462122

RESUMO

A systematic study of the influence of the first coordination sphere over the reactivity and structure of metallo-ß-lactamase (MßL) monozinc model complexes is reported. Three ZnII complexes with tripodal ligands forming the series [Zn(N-NNN)], [Zn(N-NNS)], and [Zn(N-NNO)] where N-NNX represents the tripodal donor atoms were investigated regarding their ability to mimic MßL. The tripodal series was inspired by MßL active sites in the respective subclasses, representing the (His, His, His) Zn1 site present in B1 and B3 subclasses, (His, His, Asp) present in the B3 subclass site and the thiolate present in B1 and B2 sites. The results were supported by electronic structure calculations. XAS analysis demonstrated that the ZnII electronic deficiency significantly changes in the order [Zn(N-NNS)] < [Zn(N-NNN)] < [Zn(N-NNO)]. This effect directly affects the reactivity over nitrocefin and amoxicillin, observed by the hydrolysis kinetics, which follows the same trend. NMR spectroscopy revealed the coordination of the carboxylic group in the substrate to the metal changes accordingly, affecting the hydrolysis kinetics. Our results also demonstrated that not only the Lewis acidity is changed by the ligand system but also the softness of the metal. [Zn(N-NNS)] is softened by the thiolate, promoting the ligand substitution reaction with solvents and favoring a secondary interaction with substrates, not observed for [Zn(N-NNO)]. XRD of the models reveals their similar geometric aspects in comparison to the crystal structure of GOB MßL. The present work demonstrates that the ZnII electronic details must be considered in the design of new MßL models that will further aid in the design of clinically useful inhibitors.


Assuntos
Complexos de Coordenação/química , Zinco/química , Inibidores de beta-Lactamases/química , beta-Lactamases/química , Complexos de Coordenação/farmacologia , Cinética , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Zinco/farmacologia , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo
9.
Inorg Chem ; 57(1): 218-230, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29227104

RESUMO

A combination of two elements' (Au, Zn) X-ray absorption spectroscopy (XAS) and time-dependent density functional theory (TD-DFT) allowed the elucidation of differential substitution pathways of Au(I) and Au(III) compounds reacting with biologically relevant zinc fingers (ZnFs). Gold L3-edge XAS probed the interaction of gold and the C-terminal Cys2HisCys finger of the HIV-1 nucleocapsid protein NCp7, and the Cys2His2 human transcription factor Sp1. The use of model compounds helped assign oxidation states and the identity of the gold-bound ligands. The computational studies accurately reproduced the experimental XAS spectra and allowed the proposition of structural models for the interaction products at early time points. The direct electrophilic attack on the ZnF by the highly thiophilic Au(I) resulted in a linear P-Au-Cys coordination sphere after zinc ejection whereas for the Sp1, loss of PEt3 results in linear Cys-Au-Cys or Cys-Au-His arrangements. Reactions with Au(III) compounds, on the other hand, showed multiple binding modes. Prompt reaction between [AuCl(dien)]2+ and [Au(dien)(DMAP)]3+ with Sp1 showed a partially reduced Au center and a final linear His-Au-His coordination. Differently, in the presence of NCp7, [AuCl(dien)]2+ readily reduces to Au(I) and changes from square-planar to linear geometry with Cys-Au-His coordination, while [Au(dien)(DMAP)]3+ initially maintains its Au(III) oxidation state and square-planar geometry and the same first coordination sphere. The latter is the first observation of a "noncovalent" interaction of a Au(III) complex with a zinc finger and confirms early hypotheses that stabilization of Au(III) occurs with N-donor ligands. Modification of the zinc coordination sphere, suggesting full or partial zinc ejection, is observed in all cases, and for [Au(dien)(DMAP)]3+ this represents a novel mechanism for nucleocapsid inactivation. The combination of XAS and TD-DFT presents the first direct experimental observation that not only compound reactivity, but also ZnF core specificity, can be modulated on the basis of the coordination sphere of Au(III) compounds.

10.
Medicina (Kaunas) ; 53(4): 285-293, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28888470

RESUMO

BACKGROUND AND OBJECTIVE: Although hard training is mandatory in elite level futsal training, few studies have proposed a biochemical follow up in futsal players during a whole season. Therefore, the aim of this study was to compare functional and biochemical markers in Brazilian elite level futsal players throughout a competition season. MATERIALS AND METHODS: Eight players aged 25.5±5.4 years were evaluated at three time points: preseason (T1), immediately before the FIFA®-Intercontinental-Futsal-Cup (T2), and at the end of the season (T3), with a tapering period of 1 week before T2. Functional parameters (weight, height, body fat, VO2max, heart rate, and distance ran) and blood sampling for cell count and lipid profile (cholesterol, HDL-C, LDL-C, triglycerides) were assessed at each time point. After, a Yo-Yo R2 test was carried out in each time point (T1, T2 and T3) and blood samples to assess skeletal muscle damage (creatine kinase [CK], lactate dehydrogenase [LDH]), inflammation (C-reactive protein [CRP]) and oxidative stress markers (ischemia modified albumin [IMA], and advanced oxidation protein products [AOPP]) were obtained before and after the tests. RESULTS: Although functional parameters did not change throughout the season, greater total number of erythrocytes (P≤0.05), and hemoglobin (P≤0.05) were found at T2 compared to T1. Similarly, lower LDH (P≤0.05) and CK (P≤0.05) levels were found at T2 compared to T1. CPR levels were also decreased at T2 in comparison to T1 both before and after Yo-Yo R2 test (P≤0.05), while IMA and AOPP levels showed only a season effect (P≤0.05). CONCLUSIONS: The tapering strategy was successful considering players presented lower levels of muscle damage, inflammation and oxidative stress makers before T2, which preceded the main championship of the year. These results are of great relevance, considering the team won the FIFA®-Intercontinental-Futsal-Cup, which happened at T2. Thus, it seems that routine-based biochemical markers may be useful as training control means in this population.


Assuntos
Adaptação Fisiológica , Desempenho Atlético , Frequência Cardíaca , Estresse Oxidativo , Adulto , Brasil , Proteína C-Reativa/análise , Teste de Esforço , Humanos , Masculino , Estações do Ano , Adulto Jovem
12.
J Mater Sci Mater Med ; 28(3): 37, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28144849

RESUMO

Duraplasty is necessary in nearly 30% of all neurological surgeries. Different tissues and materials have been evaluated in dura mater repair or as dural substitutes in neurosurgery. The aim was to evaluate the biocompatibility of the bacterial cellulose (BC) membranes, produced from sugarcane molasses, for dural defect repair in rats. Forty adults males Wistar rats divided into two groups: a control (ePTFE) and an experimental (BC). Bilateral frontoparietal craniectomy was performed, and a dural defect was created. The arachnoid underlying defect was disrupted with a narrow hook. The animals were observed for 120 days. There were no cases of infection, cerebrospinal fluid fistulae, delayed hemorrhages, behavior disturbances, seizures and palsies. The BC membrane showed to have suitable biocompatibility properties, was not induced immune reaction, nor chronic inflammatory response and absence of neurotoxicity signals.


Assuntos
Bactérias/química , Materiais Biocompatíveis/química , Celulose/química , Dura-Máter/efeitos dos fármacos , Animais , Dura-Máter/lesões , Sistema Imunitário , Inflamação , Masculino , Melaço , Ratos , Ratos Wistar , Saccharum , Cicatrização
15.
Elife ; 5: e14698, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27090087

RESUMO

Elucidating cardiac evolution has been frustrated by lack of fossils. One celebrated enigma in cardiac evolution involves the transition from a cardiac outflow tract dominated by a multi-valved conus arteriosus in basal actinopterygians, to an outflow tract commanded by the non-valved, elastic, bulbus arteriosus in higher actinopterygians. We demonstrate that cardiac preservation is possible in the extinct fish Rhacolepis buccalis from the Brazilian Cretaceous. Using X-ray synchrotron microtomography, we show that Rhacolepis fossils display hearts with a conus arteriosus containing at least five valve rows. This represents a transitional morphology between the primitive, multivalvar, conal condition and the derived, monovalvar, bulbar state of the outflow tract in modern actinopterygians. Our data rescue a long-lost cardiac phenotype (119-113 Ma) and suggest that outflow tract simplification in actinopterygians is compatible with a gradual, rather than a drastic saltation event. Overall, our results demonstrate the feasibility of studying cardiac evolution in fossils.


Assuntos
Peixes/anatomia & histologia , Fósseis , Coração/anatomia & histologia , Animais , Evolução Biológica , Microtomografia por Raio-X
16.
An Acad Bras Cienc ; 87(4): 2281-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26628028

RESUMO

The aim of this study was to evaluate commercial gelatin in the total replacement of bovine heart in feed training of "pacamã" Lophiosilurus alexandri in different water salinities. A completely randomized experimental design, in a 2 × 3 factorial arrangement, was performed using two types of moist ingredients (bovine heart and gelatin) and three water salinities (0.0; 2.0 and 4.0 g of salt L(-1)) with three replications. Juveniles (2.39 ± 0.08 cm standard length and 0.20 ± 0.03 g of weight) were conditioned to accept commercial diets by the technique of the gradual transition of ingredients. At the end of 36 days no differences were observed to weight gain, length gain and specific growth rate. The feed training efficiency was better (P < 0.05) with the gelatin use, 100.0%. There was a negative effect of salinity on the survival rate and management efficiency in the concentration of 4 g of salt L(-1), with values of 58.6 ± 12.0 % and 58.0 ± 12.0 %, respectively. Lophiosilurus alexandri juveniles could be feed-trained to accept commercial diets with gelatin in the total replacement of bovine heart in freshwater or salinity of 2 g of salt L(-1).


Assuntos
Ração Animal , Aquicultura , Peixes-Gato/crescimento & desenvolvimento , Gelatina/administração & dosagem , Coração , Produtos da Carne , Animais , Peixes-Gato/classificação , Bovinos , Salinidade , Fatores de Tempo , Aumento de Peso
17.
Appl Physiol Nutr Metab ; 40(7): 683-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25962716

RESUMO

Excess and incorrectly selected exercise can degrade athletic performance from an imbalance in redox homeostasis and oxidative stress, but well-planned training and nutrition can improve antioxidant capacity. The aim of the study was to investigate how nutrient intake could influence oxidative stress and cell lesion biomarkers after 5 days of training followed by a game. Blood was collected from 10 athletes at the start of training (basal), after training (pre-game), and postgame. Their acceleration capacity also was measured pre- and postgame. Blood analysis showed an increase in lactate concentration postgame (13%) and total antioxidant capacity increased both pre-game (13.1%) and postgame (12.7%), all in comparison with basal levels. An oxidative stress marker, protein carbonyl (PC), increased 3-fold over the course of the game, which correlated with a decreased acceleration (r = 0.749). For biomarkers of tissue damage, creatine kinase and aspartate transaminase (AST) increased postgame by 150% and 75%, respectively. The AST variation had a high negative correlation with energy and carbohydrate consumption and a moderate correlation with lipid and vitamin C intake. Protein intake had a positive but moderate correlation with reduced glutathione. The observed correlations suggest that nutritional monitoring can improve exercise physiological homeostasis and that PC serves as a good biomarker for oxidative stress and performance loss.


Assuntos
Desempenho Atlético/estatística & dados numéricos , Exercício Físico/fisiologia , Hóquei , Estado Nutricional/fisiologia , Estresse Oxidativo/fisiologia , Carbonilação Proteica/fisiologia , Adulto , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Aspartato Aminotransferases/sangue , Atletas , Biomarcadores/sangue , Creatina Quinase/sangue , Glutationa/sangue , Homeostase/fisiologia , Humanos , Ácido Láctico/sangue , Lipídeos/administração & dosagem , Lipídeos/sangue , Masculino , Adulto Jovem
18.
PLoS One ; 8(2): e55668, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23405192

RESUMO

BACKGROUND AND AIMS: Although acute exhaustive exercise is known to increase liver reactive oxygen species (ROS) production and aerobic training has shown to improve the antioxidant status in the liver, little is known about mitochondria adaptations to aerobic training. The main objective of this study was to investigate the effects of the aerobic training on oxidative stress markers and antioxidant defense in liver mitochondria both after training and in response to three repeated exhaustive swimming bouts. METHODS: Wistar rats were divided into training (n = 14) and control (n = 14) groups. Training group performed a 6-week swimming training protocol. Subsets of training (n = 7) and control (n = 7) rats performed 3 repeated exhaustive swimming bouts with 72 h rest in between. Oxidative stress biomarkers, antioxidant activity, and mitochondria functionality were assessed. RESULTS: Trained group showed increased reduced glutathione (GSH) content and reduced/oxidized (GSH/GSSG) ratio, higher superoxide dismutase (MnSOD) activity, and decreased lipid peroxidation in liver mitochondria. Aerobic training protected against exhaustive swimming ROS production herein characterized by decreased oxidative stress markers, higher antioxidant defenses, and increases in methyl-tetrazolium reduction and membrane potential. Trained group also presented higher time to exhaustion compared to control group. CONCLUSIONS: Swimming training induced positive adaptations in liver mitochondria of rats. Increased antioxidant defense after training coped well with exercise-produced ROS and liver mitochondria were less affected by exhaustive exercise. Therefore, liver mitochondria also adapt to exercise-induced ROS and may play an important role in exercise performance.


Assuntos
Adaptação Fisiológica , Mitocôndrias Hepáticas/fisiologia , Estresse Oxidativo , Condicionamento Físico Animal , Espécies Reativas de Oxigênio/metabolismo , Natação/fisiologia , Animais , Antioxidantes/metabolismo , Glutationa/metabolismo , Masculino , Potencial da Membrana Mitocondrial , Oxirredução , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
19.
Radiol. bras ; Radiol. bras;46(1): 1-6, jan.-fev. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-666104

RESUMO

OBJECTIVE: To evaluate sonographic features associated with morbidity in patients with chronic clinical presentations of schistosomiasis mansoni, according to the protocol proposed by the World Health Organization (WHO). MATERIALS AND METHODS: Two distinctive populations were evaluated: a) patients from an endemic area, and b) patients from a tertiary institution, with histopathologically confirmed periportal fibrosis. Inclusion criteria: diagnosis confirmed by parasitological stool examination for Schistosoma mansoni (Kato-Katz method). Exclusion criteria: positive serology for HIV, HTLV-1, HBV or HCV. The Niamey protocol on ultrasonography proposed by the WHO was utilized. RESULTS: As the measures of periportal spaces were isolatedly evaluated, no alteration was observed in 21% of the tertiary institution patients with advanced disease. As all parameters of the Niamey protocol were considered, 100% of patients from the tertiary institution, with severe disease, presented advanced periportal fibrosis. In hepatosplenic patients from endemic areas, fibrosis was not identified at ultrasonography. CONCLUSION: The sonographic protocol proposed by the WHO can detect advanced periportal fibrosis in patients with severe form of disease with higher sensitivity than the isolated measurement of periportal space. The complexity involved in the sonographic identification of early stages of periportal fibrosis in endemic areas may give rise to the field of diagnostic supplementation and to a continued improvement of sonographic protocols in these areas.


OBJETIVO: Avaliar aspectos ultrassonográficos associados à morbidade em pacientes com formas clínicas crônicas de esquistossomose mansônica, utilizando-se protocolo proposto pela Organização Mundial da Saúde (OMS). MATERIAIS E MÉTODOS: Foram avaliadas duas populações distintas: a) área endêmica e b) institucional terciária, com histopatológico confirmando fibrose. Critérios de inclusão: diagnóstico confirmado por parasitológico de fezes para Schistosoma mansoni (método Kato-Katz). Critérios de exclusão: sorologia positiva para HIV, HTLV-1, VHB ou VHC. Foi utilizado protocolo ultrassonográfico de Niamey, proposto pela OMS. RESULTADOS: Avaliando-se isoladamente as medidas dos espaços periportais, estas se mostraram sem alterações em 21% dos indivíduos com doença avançada da instituição terciária. Utilizando-se todos os parâmetros do protocolo, 100% dos indivíduos da instituição terciária, com forma grave da doença, apresentaram fibrose periportal avançada. Em pacientes hepatoesplênicos da área endêmica não se identificou fibrose à ultrassonografia. CONCLUSÃO: O protocolo ultrassonográfico proposto pela OMS detecta fibrose periportal avançada nos pacientes com forma grave da doença, com maior sensibilidade do que a medida do espaço periportal isoladamente. A complexidade de identificação das fases iniciais da fibrose periportal, em áreas endêmicas, pela ultrassonografia, pode suscitar o campo da complementação diagnóstica e a continuidade do aprimoramento dos protocolos ultrassonográficos nestas áreas.


Assuntos
Humanos , Masculino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Abdome , Esquistossomose mansoni/mortalidade , Fibrose Peritoneal , Guias como Assunto , Ultrassonografia , Ultrassonografia Doppler em Cores , Organização Mundial da Saúde
20.
J Neurol Sci ; 308(1-2): 35-40, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21737104

RESUMO

Although the importance of brain trauma as risk factor for the development of epilepsy is well established, the mechanisms of epileptogenesis are not well understood. In the present study, we revealed that the injection of a subthreshold dose of PTZ (30 mg/Kg, i.p.) after 5 weeks of injury induced by Fluid Percussion Brain Injury (FPI) decreased latency for first clonic seizures, increased the time of spent generalized tonic-clonic seizures and electrocorticographic (EEG) wave amplitude. In addition, statistical analysis revealed that N-acetylcysteine (NAC) (100mg/kg) supplementation during 5 weeks after neuronal injury protected against behavioral and electrographical seizure activity elicited by subthreshold dose of PTZ. The supplementation of this antioxidant compound also protected against the Na(+),K(+)-ATPase activity inhibition and concomitant increase in the levels of oxidative stress markers (protein carbonylation and thiobarbituric acid-reactive substances-TBARS) in site and peri-contusional cortical tissue. In summary, the current experiments clearly showed that FPI model induces early posttraumatic seizures and suggest that an alteration in the lipid/protein oxidation, membrane fluidity, and Na(+),K(+)-ATPase activity may be correlated with neuronal excitability, a significant component of the secondary injury cascade that accompanies TBI.


Assuntos
Lesões Encefálicas/metabolismo , Radicais Livres/metabolismo , Pentilenotetrazol/toxicidade , Convulsões/induzido quimicamente , Convulsões/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Lesões Encefálicas/complicações , Lesões Encefálicas/enzimologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Masculino , Ratos , Ratos Wistar , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Convulsões/enzimologia , ATPase Trocadora de Sódio-Potássio/fisiologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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