L-Asparaginase

L-Asparaginase (ASNase, EC 3.5.1.1) is a tetrameric aminohydrolase enzyme that catalyses the hydrolysis of the amino acid L-Asparagine into ammonia and L-aspartic acid. ASNase is present in different organisms such as bacteria, fungi, plant tissues and algae. ASNase is used in the pharmaceutical field as an anticancer drug for the treatment of acute lymphoblastic leukemia (ALL) and other malignant diseases such as Hodgkin’s disease. In the food sector, ASNase is used to prevent the formation of acrylamide, a toxic compound formed when starch-rich foods are cooked at temperatures above 100 °C. ASNase can also be used as a biosensor for the detection of L-asparagine levels.publishe

Comparação dos efeitos da ventilação mecânica não invasiva contínua e intermitente sobre parâmetros cardiorrespiratórios e modulação autonômica de indivíduos saudáveis

Modelo do estudo: Estudo transversal. Objetivo: Avaliar a influência da Ventilação Mecânica não Invasiva (VMNI) de forma contínua e intermitente sobre a modulação autonômica cardíaca e parâmetros cardiorrespiratórios em mulheres saudáveis. Métodos: Vinte voluntárias realizaram duas modalidades de VMNI: contínua por meio do CPAP e intermitente por meio do Reanimador de Muller. Inicialmente permaneceram em repouso em respiração espontânea por 20 minutos. Em seguida foram submetidas a 20 minutos de aplicação de VMNI com a técnica selecionada e por fim permaneceram 20 minutos em repouso em respiração espontânea. Os parâmetros cardiorrespiratórios e variabilidade da frequência cardíaca (VFC) foram mensurados em todos estes momentos. Resultados: Não houve diferenças significantes quando comparadas as duas técnicas. Observaram-se diferenças nos parâmetros cardiorrespiratórios e VFC quando analisadas individualmente. Menores valores de frequência cardíaca e frequência respiratória foram observados na modalidade contínua quando comparado os valores durante a ventilação com respiração espontânea (p<0,005). Em ambas técnicas observaram-se aumentos significantes de SpO2 durante a ventilação em comparação a respiração espontânea. Observou-se aumento da modulação parassimpática (RMSSD, HF ms2 e SD1) e da variabilidade global (SDNN, RR triangular e SD2) em ambas as técnicas quando comparado ventilação e respiração espontânea (p<0,005). Conclusão: Não houve diferença quando comparadas as duas modalidades de VMNI. Contudo, quando analisadas individualmente observam-se comportamento diferentes dos parâmetros cardiorrespiratórios e na modulação autonômicaStudy design: Cross-sectional study. Objective: To evaluate the influence of continuous and intermittent noninvasive mechanical ventilation (NIV) on cardiac autonomic modulation and cardiorespiratory parameters in healthy women. Methods: Twenty subjects performed two types of NIV: continuous through CPAP and intermittent through Müller Reanimator. Initially they remained at rest for 20 minutes in spontaneous breathing. Then volunteers were subjected to 20 minutes of NIV application with the selected technique and finally remained at rest for 20 minutes in spontaneous breathing. Cardiorespiratory parameters and heart rate variability (HRV) were measured in all these moments. Results: There were no significant differences when comparing the two techniques. Differences were observed in HRV and cardiorespiratory parameters when analyzed individually. Lower values of heart rate and respiratory rate were observed in continuous ventilation when compared to values during ventilation with spontaneous breathing (p <0.005). In both techniques we observed significant increases in SpO2 during ventilation compared to spontaneous breathing. We observed an increase in parasympathetic modulation (RMSSD, HF ms2 and SD1) and overall variability (SDNN, RR triangular and SD2) in both techniques when compared ventilation to spontaneous breathing (p <0.005). Conclusion: There was no difference comparing the two types of NIV. However, when analyzed individually we observe different behavior of cardiorespiratory parameters and autonomic modulatio

Efeitos de um programa domiciliar de exercícios após um treinamento resistido supervisionado em pacientes com doença pulmonar obstrutiva crônica

Design of the study: clinical Trial. Objective: This study aimed to evaluate the effects of a homebased resistance exercise program with elastic tubing after supervised resistance training on peripheral muscle strength and quality of life in patients with chronic obstructive pulmonary disease (COPD). Methods: The study included 22 COPD patients, aged 55-70 years. Peripheral muscle strength and quality of life were evaluated through digital dynamometer and Chronic Respiratory Disease Questionnaire (CRDQ) respectively after supervised resistance training program, and then the patients were divided into two groups: home-based treatment (n = 10) and control (n = 12). After 16 weeks the assessments were repeated. Results: The home resistance training showed no significant increase in peripheral muscle strength and quality of life, however, was able to maintain the gains made in the previous supervised training. Conclusion: The continuity of home-based treatment did not promote additional improvements to supervised training after the protocol, since the gains were maintained in both assessed groups after 4 monthsDesenho do estudo: ensaio clínico. Objetivo: Avaliar os efeitos de um programa de exercícios resistidos em domicílio, com tubos elásticos, após o treinamento resistido supervisionado sobre a força muscular periférica e qualidade de vida de pacientes com doença pulmonar obstrutiva crônica (DPOC). Métodos: O estudo incluiu 22 pacientes com DPOC, com idade entre 55-70 anos. A força muscular periférica e a qualidade de vida foram avaliados por meio da dinamometria e do questionário Chronic Respiratory Questionare (CRQ), respectivamente, após o programa de treinamento de resistência supervisionado, e, em seguida, os pacientes foram divididos em dois grupos: tratamento domiciliar (n = 10) e controle (n = 12). Após 16 semanas, as avaliações foram repetidas. Resultados: O treinamento resistido em domicílio não mostrou aumento significativo sobre a força muscular periférica e qualidade de vida, no entanto, foi capaz de manter os ganhos obtidos após o programa de treinamento supervisionado. Conclusão: A continuidade do tratamento em domicílio não promoveu melhorias adicionais após o protocolo, uma vez que os ganhos foram mantidos nos dois grupos avaliados após 4 mese

Acute effect of aerobic exercise in different intensities in mucociliary clearance of patients with COPD

Design of the Study: Clinical Trial. Objective (s): To analyze the acute effect of aerobic exercise at different intensities in mucociliary clearance in patients with COPD, and to investigate possible associations of the autonomic nervous system in this response. Methods: 22 COPD patients underwent an initial evaluation for collecting personal data and spirometry to assess lung function. It was performed a progressive treadmill test for aerobic exercise prescription. Finally two randomized sessions of aerobic exercise with intensity of 60 % and 90 % of peak speed reached during the incremental test ( vVO2peack ) were performed with at least 24 hours of rest between them. The mucociliary clerance was assessed before and after the exercise sessions by testing the saccharin transit time (STT). Assessment of autonomic modulation was performed by heart rate variability (HRV) which continued throughout the protocol. Results: The values obtained in the STT test after aerobic exercise at 60 % of vVO2peack (9,08 minutes ± 4,96 ) was lower when compared to the STT before exercise ( 11,96 ± 6,31, p = 0,005 ) . That response also occurred after aerobic exercise at 90% of vVO2peack ( 8,90 ± 4,21 min ) compared to baseline ( 12,94 ± 7,22 , p = 0,023 ). Correlation analysis between the final values of STT test and HRV indexes did not show significant differences. Conclusions: Patients with COPD showed acceleration of mucociliary clerance right after a session of aerobic exercise. It was not possible to observe the association of autonomic modulation in this responseModelo do Estudo: Experimental. Objetivo(s) do estudo: Analisar o efeito agudo do exercício aeróbio em diferentes intensidades no transporte mucociliar de pacientes com DPOC, bem como investigar possíveis associações do sistema nervoso autônomo nesta resposta. Metodologia: Foram analisados 22 pacientes com DPOC que realizaram avaliação inicial para coleta de dados pessoais e espirometria a fim de avaliar a função pulmonar. Realizou-se um teste progressivo em esteira ergométrica para prescrição do exercício aeróbio. Por fim foram realizadas duas sessões de exercício aeróbio randomizadas em esteira ergométrica com intensidade de 60% e 90% do pico da velocidade atingida no teste incremental (vVO2pico) com pelo menos 24 horas de descanso entre elas. O transporte mucociliar foi avaliado antes e após realização do exercício por meio do teste do tempo de trânsito da sacarina (TTS). A avaliação da modulação autonômica foi realizada por meio da variabilidade da frequência cardíaca (VFC) a qual prosseguiu durante todo o protocolo. Resultados: Os valores obtidos no teste de TTS dos pacientes com DPOC após exercício aeróbio a 60% da vVO2pico (9,08 ± 4,96 minutos) foi menor comparado ao TTS antes do exercício (11,96 ± 6,31; p = 0,005). O que também ocorreu após exercício aeróbio a 90% da vVO2pico (8,90 ± 4,21 minutos) quando comparado ao momento basal (12,94 ± 7,22; p = 0,023). As análises de correlação entre os valores finais de TTS e índices da VFC não apontaram diferenças significativas. Conclusões: Pacientes com DPOC apresentaram aceleração da transportabilidade mucociliar frente a uma sessão de exercício aeróbio. Não foi possível observar associação da modulação autonômica nesta resposta após o exercíci

Quantitative-spatial assessment of soil contamination in S. Francisco de Assis due to mining activity of the Panasqueira mine (Portugal)

Through the years, mining and beneficiation processes produces large amounts of As-rich mine wastes laid up in huge tailings and open-air impoundments (Barroca Grande and Rio tailings) that are the main source of pollution in the surrounding area once they are exposed to the weathering conditions leading to the formation of AMD and consequently to the contamination of the surrounding environments, in particularly soils. In order to investigate the environmental contamination impact on S. Francisco de Assis (village located between the two major impoundments and tailings) agricultural soils, a geochemical survey was undertaken to assess toxic metals associations, related levels and their spatial distribution, and to identify the possible contamination sources. According to the calculated contamination factor, As and Zn have a very high contamination factor giving rise to 65.4 % of samples with a moderate to high pollution degree; 34.6 % have been classified as nil to very low pollution degree. The contamination factor spatial distribution put in evidence the fact that As, Cd, Cu, Pb, and Zn soils contents, downstream Barroca Grande tailing, are increased when compared with the local Bk soils. The mechanical dispersion, due to erosion, is the main contamination source. The chemical extraction demonstrates that the trace metals distribution and accumulation in S. Francisco de Assis soils is related to sulfides, but also to amorphous or poorly crystalline iron oxide phases. The partitioning study allowed understanding the local chemical elements mobility and precipitation processes, giving rise to the contamination dispersion model of the study area. The wind and hydrological factors are responsible for the chemical elements transport mechanisms, the water being the main transporter medium and soils as one of the possible retention media

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types