330 research outputs found
Plant Health and the Science of Pests and Diseases
The health/disease duality has developed alongside human history either as a struggle for survival or as a challenge of the human being to effectively get to know himself. To speak about pests and diseases of plants may not be as exciting as when speaking of human beings; however, entomology and phytopathology hold methodological similarities to conventional medicine, which, thus, allow for correlations among them. After all, plant protection and human medical science are based under common epistemological principles of modern scientific thought. Hence, the goal of this essay is to disclose certain disagreements of the disciplines of phytopathology and entomology with agroecological based science; yet, giving way to a discussion according to ecological principles. This is a theoretical essay, based on bibliographical research and on the direct experience of the authors with family farmers in the South of Brazil during the last 20 years
Spirulina does not decrease muscle damage nor oxdidative stress in cycling athletes with adequate nutritional status
The objective of this study was to assess the effect of Spirulina maxima on oxidative stress and muscle damage in cycling athletes subjected to high volume and intensity of training. Eighteen male athletes were randomly divided into an experimental group (n=11) with age 27.8±3.5 and placebo (n=7) with age 34.3±2.3 in a double-blind fashion. They carried out a protocol of Spirulina dietary supplementation (7.5 g/day) of placebo for four weeks and maintained their trainings during this period. A nutritional anamnesis was performed and blood tests were done to determine pre and post levels of creatine kinase (CK), lactic dehydrogenase (LHD), superoxide dismutase (SOD) and malondialdehyde (MDA). The supplemented and placebo groups performed the same volume training, has adequate macronutrients and antioxidant vitamins ingestion before study, as well as initial CK, LDH, SOD and MDA levels. Supplementation did not promote a significant alteration in CK levels on supplemented group (158.4±16.3 for 140.0±16.6 U/l, p>0.05), LDH (420±13.2 for 394.9±27.9 UI/l, p>0.05), MDA (2.8±0.2 for 2.9±0.4 nmol/ml, p>0.05), nor an increase in the SOD (7.3±0.6 for 7.0±0.6 U/mg Hb, p>0.05). We conclude that administration of Spirulina does not interfere in the magnitude of muscle damage nor in antioxidant status of cycling athletes that practice intense training
Estudo da mutação do recetor do fator de crescimento epidérmico, durante 5 anos, numa população de doentes com cancro do pulmão de não pequenas células
ResumoIntroduçãoEm 2006, a Unidade de Pneumologia Oncológica do Serviço de Pneumologia do Centro Hospitalar de Vila Nova de Gaia/Espinho iniciou a sequenciação da mutação do recetor do fator de crescimento epidérmico (EGFR) em doentes com CPNPC selecionados e desde 2010 realiza a sequenciação sistematicamente em todos os doentes, independentemente da histologia, hábitos tabágicos, idade ou sexo. O objetivo deste trabalho foi caracterizar o grupo de doentes que efetuou a sequenciação entre 2006-2010, determinar a frequência da mutação EGFR, avaliar as sobrevidas globais e após uso de inibidores da tirosina quinase (ITK), nos doentes que efetuaram esta terapêutica em 2.a e 3.a linha com conhecimento do estado da mutação do EGFR.MétodosAnálise estatística descritiva dos doentes que efetuaram sequenciação EGFR em 2006-2010 e sobrevida mediana global nos doentes que efetuaefetuaram ITK em 2.a e 3.a linha. Registo do material disponível para análise e demora média de resultado do exame, de acordo com o material enviado.ResultadosA sequenciação foi efetuada em 374 doentes, 71,1% sexo masculino, 67,1% não/ex-fumadores, 32,9% fumadores; 57,8% adenocarcinoma e 23,5% carcinoma epidermoide (CE). A mutação foi detetada em 49 doentes (13,1%). No total dos doentes estudados, a taxa de mutação foi de 9% no sexo masculino e 23% no sexo feminino. A sobrevida mediana global após o uso de erlotinib foi de 14 meses para os doentes com mutação positiva do EGFR versus 6 meses nos doentes não mutados (p = 0,003).ConclusãoO nosso grupo teve uma taxa de mutação global de 13,1%, com predomínio no sexo feminino, não fumadores, histologia adenocarcinoma. Em doentes selecionados (2006/2009), a taxa de mutação foi de 16%; nos doentes não selecionados (2010) foi de 10,4%. Este estudo tem vindo a permitir um melhor conhecimento da taxa de mutação do EGFR na população portuguesa, bem como avaliar os resultados das sobrevidas dos doentes após uso de inibidores da tirosina quinase (ITK), efetuada em 2.a e 3.a linha com conhecimento prévio do estado da mutação do EGFR, tendo sido encontradas diferenças nas sobrevidas nos 2 grupos de doentes (mutados e não mutados) com significado estatístico.A pesquisa mutação do EGFR deve ser efetuada em todos os doentes com CPNPC, dando possibilidade a um número considerável de doentes de poder efetuar um tratamento de 1.a linha com ITK (doentes mutados), bem como de poder usufruir de outros esquemas de quimioterapia, quando progredirem.AbstractIntroductionIn 2006, the Vila Nova de Gaia/Espinho Hospital Centre Pulmonary Oncology Unit started performing EGFR (Epidermal Growth Factor Receptor) mutation sequencing in selected patients with NSCLC and systematically in all patients since 2010, regardless of histology, smoking habits, age or sex. The aim of this study was to characterize the group of patients that carried out the sequencing between 2006-2010, to determine EGFR mutation frequency, to evaluate the overall survival and the survival after the use of tyrosine kinase inhibitors (TKI), in patients who performed this therapy in second and third line, knowing the EGFR mutation status.MethodsDescriptive statistical analysis of patients who did EGFR sequencing in 2006-2010 and of overall survival in patients treated with TKI as 2nd and 3rd line therapy. Record of the material available for analysis and average delay of exam results, according to the material submitted.ResultsThe sequencing was performed in 374 patients, 71,1% males, 67,1% non/ex-smokers, 32,9% smokers, 57,8% adenocarcinoma and 23,5% squamous cell carcinoma (SCC). The mutation was detected in 49 patients (13,1%). In all studied patients, the mutation rate was 9% in males and 23% in females. Median overall survival after erlotinib use of was 14 months for patients with positive EGFR mutation versus 6 months in not mutated patients (p = 0.003).ConclusionOur group had an overall mutation rate of 13.1% with female, non-smokers, adenocarcinoma histology predominance. In selected patients (2006/2009), the mutation rate was 16%, in not selected patients (2010) the mutation rate was 10.4%. This study has permitted a better understanding of the EGFR mutation rate in the Portuguese population as welll as an evaluation of the patients survival after the use of of tyrosine kinase inhibitors, in second and third line therapy with previous knowledge of the EGFR mutational status. Statistical significant differences in survival were found in the two patient groups (EGFR mutated and non mutated).The EGFR mutation research should be performed in all patients with NSCLC, giving the possibility to a considerable number of patients to perform a first line treatment with TKI (EGFR mutated patients) and the advantage of performing other chemotherapy schemes, when progression occurs
Avaliação de biofertilizantes, extratos vegetais e diferentes substâncias alternativas no manejo de tripes em cebola em sistema orgânico.
Avaliou-se substâncias alternativas no manejo de tripes (Thrips tabaci Lind.), em cebola, cv, Crioula, no sistema orgânico. Os experimentos foram conduzidos na EPAGRI, Ituporanga (SC). Os períodos entre transplante e colheita foram de 11/09/1996 a 10/01/1997 e 13/08/1997 a 11/12/1997. O delineamento foi de blocos ao acaso com 8 tratamentos em 1996 e 12 tratamentos em 1997 e quatro repetições. Em 1996 os tratamentos incluíram o biofertilizante anaeróbico 50%, biofertilizante aeróbico 5%, sulfato de manganês 1%, extrato hidroalcoólico de própolis 0,2%, macerado de ervas (“fersoral”) 2% e 4%, extrato de fumo (Nicotiana tabacum) 2 L ha-1 + 1% detergente neutro, testemunha sem aplicação. Em 1997 os tratamentos incluíram o macerado de ervas (“fersoral”) 5% 10%, enxofre pó molhável 0,25% + extrato hidroalcoólico de própolis 0,2% + extrato de samambaia 3%, biofertilizante anaeróbico 50%, biofertilizante aeróbico 5%, extrato de losna (Artemisia verlotorum) 3%, extrato de timbó (Ateleia glazioviana) 0,5%, extrato de samambaia (Pteridium aquilinum) 10%, extrato de erva-de-santa-maria (Chenopodium ambrosioides) 10%, extrato de cinamomo (Melia azedarach) 10%,extrato de camomila (Matricaria chamomilla) 5%, testemunha sem aplicação. Para aplicação dos produtos empregou-se pulverizador de pressão constante a base de CO2. Os tratamentos não causaram redução significativa na incidência de tripes e aumentos significativos na produtividade
The Role of Rosmarinic Acid on the Bioproduction of Gold Nanoparticles as Part of a Photothermal Approach for Breast Cancer Treatment.
Breast cancer is a high-burden malignancy for society, whose impact boosts a continuous search for novel diagnostic and therapeutic tools. Among the recent therapeutic approaches, photothermal therapy (PTT), which causes tumor cell death by hyperthermia after being irradiated with a light source, represents a high-potential strategy. Furthermore, the effectiveness of PTT can be improved by combining near infrared (NIR) irradiation with gold nanoparticles (AuNPs) as photothermal enhancers. Herein, an alternative synthetic method using rosmarinic acid (RA) for synthesizing AuNPs is reported. The RA concentration was varied and its impact on the AuNPs physicochemical and optical features was assessed. Results showed that RA concentration plays an active role on AuNPs features, allowing the optimization of mean size and maximum absorbance peak. Moreover, the synthetic method explored here allowed us to obtain negatively charged AuNPs with sizes favoring the local particle accumulation at tumor site and maximum absorbance peaks within the NIR region. In addition, AuNPs were safe both in vitro and in vivo. In conclusion, the synthesized AuNPs present favorable properties to be applied as part of a PTT system combining AuNPs with a NIR laser for the treatment of breast cancer
The European VLF/LF radio network to search for earthquake precursors: setting up and natural/man-made disturbances
In the last years disturbances in VLF/LF radio signals related to seismic activity have been presented. The radio data were collected by receivers located on the ground or on satellites. The ground-based research implies systematic data collection by a network of receivers. Since 2000 the “Pacific VLF network”, conducted by Japanese researchers, has been in operation. During 2008 a radio receiver was developed by the Italian factory Elettronika (Palo del Colle, Bari). The receiver is equipment working in VLF and LF bands. It can monitor 10 frequencies distributed in these bands and, for each of them, it saves the power level. At the beginning of 2009, five receivers were made for the realization of the “European VLF/LF Network”; two were planned for Italy and one for Greece, Turkey and Romania, respectively. In 2010 the network was enlarged to include a new receiver installed in Portugal. In this work, first the receiver and its setting up in the different places are described. Then, several disturbances in the radio signals related to the transmitters, receivers, meteorological/geomagnetic conditions are presented and described
Electrochemical sensing of ecstasy with electropolymerized molecularly imprinted poly(o-phenylenediamine) polymer on the surface of disposable screen-printed carbon electrodes
This study demonstrates the ability of an electrochemical sensor based on molecularly imprinted polymers (MIPs) to selectively quantify 3,4-methylenedioxymethamphetamine (MDMA), also known as ecstasy, in biological samples. The device was constructed using ortho-phenylenediamine (o-PD) as the MIP’s building monomer at the surface of a screen-printed carbon electrode (SPCE). The step-by-step construction of the SPCE-MIP sensor was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Density functional theory (DFT) calculations and modelling were performed not only to understand template-monomer interaction but also to comprehend which possible polymer structure - linear or ramified poly(o-PD) – indeed interacts with the analyte. The prepared sensor worked by directly measuring the MDMA oxidation signal through square-wave voltammetry (SWV) after an incubation period of 10 min. Several parameters were optimized, such as the monomer/template ratio, the number of electropolymerization scanning cycles, and the incubation period, to obtain the best sensing efficiency. Optimized sensors exhibited suitable selectivity, repeatability (2.6%), reproducibility (7.7%) and up to one month of stable response. A linear range up to 0.2 mmol L−1 was found with an r2 of 0.9990 and a limit of detection (LOD) and quantification (LOQ) of 0.79 and 2.6 μmol L−1 (0.15 and 0.51 μg mL−1), respectively. The proposed sensor was successfully applied to human blood serum and urine samples, showing its potential for application in medicine and in forensic sciences.This work received financial support from FCT/MCTES through national funds and was co-financed by FEDER, under Partnership Agreement PT2020-UID/QUI/50006/2013-POCI/01/0145/FEDER/007265. RASC wishes to acknowledge FCT for her PhD fellowship (PD/BD/127797/2016) from the PhD Programme in Medicines and Pharmaceutical Innovation (i3DU). AACB (grants 2014/25770-6 and 2015/01491-3) and LMG (grant 2018/14425-7) thank the São Paulo Research Foundation (FAPESP) for financial support. AACB (grant 309715/2017-2) also thanks the Brazilian National Research Council (CNPq) for financial support and fellowships. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001.info:eu-repo/semantics/publishedVersio
Avaliação Da Produção De Látex Em Mangabeiras Do Cerrado Goiano
The mangabeira latex, plant native from Cerrado, shows biotechnological potential for the development of new drugs. Little is known about the latex productivity and bleeding methods in mangabeira, which is usually utilized in extractive way for fruit production. Aiming to broaden our knowledge about mangabeira latex production we evaluate the productivity associated with bleeding methods; environmental conditions; anatomical aspects from the bark and seasonal properties. As results we observed that the bleeding method commonly used in rubber tree is not appropriated to mangabeira; the most productive bleeding method was using a knife in stalk region. The bark thickness and lactiferous vessels number are associated with latex production. Anatomical analysis showed that the bark in mangabeira is thick and the lactiferous vessels are deeply localized, in this way some superficial bleeding methods are not able to reach the vessels. It was also observed that the increase in environmental temperature has a positive influence on the productivity of latex and that during the fruiting time the latex production is significantly lower. This probably occurs because the plant uses part of the secondary metabolites for fruit formation, which reduced the availability of these metabolites to latex production. © 2016, Universidade Federal de Santa Maria. All rights reserved.26393994
Results from On-The-Ground Efforts to Promote Sustainable Cattle Ranching in the Brazilian Amazon
Agriculture in Brazil is booming. Brazil has the world’s second largest cattle herd and is the second largest producer of soybeans, with the production of beef, soybeans, and bioethanol forecast to increase further. Questions remain, however, about how Brazil can reconcile increases in agricultural production with protection of its remaining natural vegetation. While high hopes have been placed on the potential for intensification of low-productivity cattle ranching to spare land for other agricultural uses, cattle productivity in the Amazon biome (29% of the Brazilian cattle herd) remains stubbornly low, and it is not clear how to realize theoretical productivity gains in practice. We provide results from six initiatives in the Brazilian Amazon, which are successfully improving cattle productivity in beef and dairy production on more than 500,000 hectares of pastureland, while supporting compliance with the Brazilian Forest Code. Spread across diverse geographies, and using a wide range of technologies, participating farms have improved productivity by 30–490%. High-productivity cattle ranching requires some initial investment (R410–2180/ha), with average pay-back times of 2.5–8.5 years. We conclude by reflecting on the challenges that must be overcome to scale up these young initiatives, avoid rebound increases in deforestation, and mainstream sustainable cattle ranching in the Amazon
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