113 research outputs found

    Immobilization of a Commercial Lipase from Penicillium camembertii (Lipase G) by Different Strategies

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    The objective of this work was to select the most suitable procedure to immobilize lipase from Penicillium camembertii (Lipase G). Different techniques and supports were evaluated, including physical adsorption on hydrophobic supports octyl-agarose, poly(hydroxybutyrate) and Amberlite resin XAD-4; ionic adsorption on the anionic exchange resin MANAE-agarose and covalent attachment on glyoxyl-agarose, MANAE-agarose cross-linked with glutaraldehyde, MANAE-agarose-glutaraldehyde, and epoxy-silica-polyvinyl alcohol composite. Among the tested protocols, the highest hydrolytic activity (128.2 ± 8.10 IU·g−1 of support) was achieved when the lipase was immobilized on epoxy-SiO2-PVA using hexane as coupling medium. Lipase immobilized by ionic adsorption on MANAE-agarose also gave satisfactory result, attaining 55.6 ± 2.60 IU·g−1 of support. In this procedure, the maximum loading of immobilized enzyme was 9.3 mg·g−1 of gel, and the highest activity (68.8 ± 2.70 IU·g−1 of support) was obtained when 20 mg of protein·g−1 was offered. Immobilization carried out in aqueous medium by physical adsorption on hydrophobic supports and covalent attachment on MANAE-agarose-glutaraldehyde and glyoxyl-agarose was shown to be unfeasible for Lipase G. Thermal stability tests revealed that the immobilized derivative on epoxy-SiO2-PVA composite using hexane as coupling medium had a slight higher thermal stability than the free lipase

    Dermoid and epidermoid cysts of the oral cavity : a 48-year retrospective study with focus on clinical and morphological features and review of main topics

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    Dermoid and epidermoid cysts are slow-growing, benign developmental cysts that arise from ectodermal tissue and can occur anywhere in the body. Less than 7% of these cysts involve the head and neck region, with only 1.6% of cases presenting in the oral cavity. To evaluate the clinical and histopathological features of dermoid (DCs) and epidermoid (ECs) cysts stored in the archives of a referred Oral Pathology Service over a 48-year-period, and to review current concepts about these cysts. All DCs and ECs were reviewed, and clinical data were obtained from the patient records. Fourteen cases of DCs and thirteen cases of ECs were re-evaluated microscopically by 2 oral pathologists. Among 15.387 cases, 14 (0.09%) had a histopathological diagnosis of DCs and 13 (0.08%) of ECs. For DCs, ten (71.4%) patients were women, with the mean age of 37.2 years. All DCs were lined by a stratified squamous epithelium (100%), with gut and respiratory epithelium observed in 1 (7.1%) and 2 (14.3%) cases, respectively. Chronic inflammatory cells, melanin, multinucleated giant cell reaction, and Pacini bodies were also observed. For ECs, eight (61.5%) cases were in women, and the mean age was 38.2 years. All ECs were lined by a stratified squamous epithelium (100%). Chronic inflammatory cells, melanin pigmentation, and adipose tissue were observed in the fibrous capsule. Our results suggest that stratified squamous epithelium is the predominant epithelial lining of these cystic lesions. Also, we may find some unusual findings in DCs, such as Pacini bodies

    Resumen de la Tarea de Anålisis de Sentimientos Basado en Aspectos en Portugués (ABSAPT) en IberLEF 2022

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    Este artículo presenta la Tarea sobre Anålisis de Sentimientos basado en Aspectos en Portugués (ABSAPT), realizada en el IberLEF 2022. Les pedimos a los participantes que desarrollaran sistemas capaces de identificar aspectos (AE) y extraer la polaridad (ASC) en textos escritos en portugués. Doce equipos se inscribieron en la tarea, entre los cuales cinco presentaron predicciones e informes técnicos. El sistema con mejor rendimiento logró un valor de precisión (Acc) de 0,67 para la subtarea de AE (Equipo Deep Learning Brasil) y un valor de precisión equilibrada (Bacc) de 0,82 para la subtarea de ASC (Equipo Deep Learning Brasil).This paper presents the task on Aspect-Based Sentiment Analysis in Portuguese (ABSAPT), held within Iberian Languages Evaluation Forum (IberLEF 2022). We asked the participants to develop systems capable of extracting aspects (AE) and classifying sentiment of aspects (ASC) in texts. We created one corpora containing reviews about hotels. Twelve teams registered to the task, among which five submitted predictions and technical reports. The best performing system achieved an Accuracy (Acc) value of 0.67 in AE sub-task (Team Deep Learning Brasil) and a Balanced Accuracy (Bacc) value of 0.82 in ASC sub-task (Team Deep Learning Brasil).This work was financed in part by the following Brazilian research agencies: CAPES and CNPq

    Produção de clamidósporos de Pochonia chlamydosporia em diferentes substratos

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    ClamidĂłsporos sĂŁo estruturas de sobrevivĂȘncia do fungo nematĂłfago Pochonia chlamydosporia. Objetivou-se, com este trabalho, avaliar diferentes substratos, teores de ĂĄgua e formas de inĂłculo para a produção in vitro de clamidĂłsporos de P. chlamydosporia. Inicialmente, testaram-se os substratos grĂŁos de milho triturado, grĂŁos de arroz e casca de cafĂ© e os tipos de inĂłculo meio lĂ­quido concentrado ou diluĂ­do (1:40) e discos de cultura, colonizados por P. chlamydosporia. Posteriormente, testou-se o substrato grĂŁos de milho triturado suplementado ou nĂŁo com caldo de batata com os inĂłculos do fungo nas formas de discos de micĂ©lio ou suspensĂŁo aquosa. As maiores produçÔes de clamidĂłsporos g-1 de substrato foram obtidas nos substratos grĂŁos de milho triturado e casca de cafĂ©, e as melhores formas de inĂłculo foram meio lĂ­quido diluĂ­do (1:40) e discos de micĂ©lio. A suplementação do substrato grĂŁos de milho triturado com caldo de batata nĂŁo aumentou a produção de clamidĂłsporos do fungo e a melhor forma de inĂłculo do fungo foi a de discos de micĂ©lio. AlĂ©m disso, testaram-se os substratos canjica, grĂŁos de arroz, casca de cafĂ© e fibra de coco, umedecidos com diferentes quantidades de ĂĄgua; o substrato casca de cafĂ© umedecido por diferentes perĂ­odos; a casca de cafĂ© enriquecida ou nĂŁo com sacarose e farinha de arroz e o substrato grĂŁos de arroz esterilizado no forno micro-ondas com diferentes quantidades de ĂĄgua. Apenas o substrato grĂŁos de arroz, em todas as quantidades de ĂĄgua testadas, apresentou maior produção de clamidĂłsporos. NĂŁo houve diferença na produção de clamidĂłsporos no substrato casca de cafĂ© umedecido por diferentes perĂ­odos e apenas quando a casca de cafĂ© foi enriquecida com farinha de arroz, apresentou maior mĂ©dia de clamidĂłsporos g-1 de substrato. Todos os tratamentos apresentaram grande produção de clamidĂłsporos g-1 quando o substrato utilizado foi o de grĂŁos de arroz tratados no forno de micro-ondas. O melhor meio de cultivo de P. chlamydosporia para a produção de clamidĂłsporos foi o substrato contendo grĂŁos de arroz.Chlamydospores are survival structures of the nematophagous fungus Pochonia chlamydosporia. The objective of this study was to evaluate different substrates, different contents of water and kinds of inoculum for the production of Pochonia chlamydosporia chlamydospores. The substrates evaluated were: milled maize, rice grains and coffee husk; all of them were inoculated with disks of culture, concentrated liquid media or diluted liquid media (1:40) colonized by P. chlamydosporia. Besides, the substrates milled maize, supplemented or not with potato broth, and inoculated with fungus disks or aqueous suspension were evaluated. Milled maize and coffee husk were the best substrates for chlamydospores production. The best inoculum kinds were disks of culture and diluted liquid media (1:40) colonized by P. chlamydosporia. The supplementation of milled maize with potato broth did not improve the production of chlamydospores, and the best inoculum form was disks of fungus. Moreover, it was also studied the substrates rice grains, coffee husk and coconut fibers with different rates of water; the substrate coffee husk moistened by different periods; the supplementation of coffee husk with rice flour or dextrose; and the substrate grains of rice sterilized in microwave oven with different rates of water. The substrate grains of rice, in all of the amounts of water tested showed increase in production of chlamydospores. There was no difference in the chlamydospores production of the coffee husk substrate, when moistened by different periods of time and only when it was supplemented with rice flour it showed higher mean of clamydospores per gram of substrate. All treatments evaluated showed higher production of chlamydospores in the substrate grains of rice treated in the microwave oven. The best substrate for the production of chlamydospores of P. chlamydosporia was the rice grains

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

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    This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic
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