369 research outputs found
Avaliação morfológica de fibras eletrofiadas de policaprolactona em função do tipo de solvente
Recentemente, estratégias da engenharia tecidual para o tratamento de feridas e queimaduras prevê o uso debiomateriais nanoestruturados capazes de facilitar a regeneração da pele e a cura das feridas. Um dosprocessos utilizados para a obtenção deste tipo de biomaterial é a eletrofiação. Por meio deste processo épossível formar filmes compostos por nanofibras poliméricas a partir de polímeros em solução e, assim,mimetizar a matriz extracelular da pele. Dentre os polímeros mais comumente utilizados, a policaprolactona(PCL) destaca-se por ser solúvel em diversos tipos de solventes. Este trabalho teve como objetivo principalavaliar a influência da condutividade elétrica de diferentes solventes na morfologia de fibras de PCLproduzidas por eletrofiação. Também foi estudado o efeito da massa molar e da viscosidade da solução,assim como da vazão e da voltagem na morfologia das fibras. Foram usados como solventes: ácido acético(AC), ácido fórmico (AF), clorofórmio (CLO), diclorometano (DCM) e dimetilformamida (DMF). Foipossível obter fibras com diâmetros uniformes e livres de defeitos, como contas, utilizando o sistema desolventes DCM:DMF 70:30 (m/m), que, apesar de diminuir a massa molar do polímero durante aeletrofiação, gerou a melhor condição para a fiação do PCL. A condutividade elétrica influenciou diretamenteas outras variáveis do processamento. Quando solventes com valores maiores de condutividade elétrica foramutilizados, foi necessária menor voltagem para a formação de fibras livre de defeitos. Os resultadosmostraram que a condutividade elétrica da solução é uma variável de grande importância na escolha dascondições experimentais para eletrofiação de PCL e, portanto, também deve ser melhor avaliada.Palavras-chave: Eletrofiação, Policaprolactona, Nanofibras, Morfologia, Engenharia Tecidual
Oesophageal Metastasis from Colorectal Cancer
Metastasis to the oesophagus is most frequently described in association with lung or breast cancer. Diagnosis is frequently complicated as often only normal tissue is present in endoscopic biopsy specimens. Although oesophagectomy for metastasis has been described, few patients are suitable for curative resection. We report the case of a 62-year-old man who developed an oesophageal metastasis from colorectal cancer and review the available literature
Identification of Research gaps on Municipal Solid Waste Management from Data Indexed in the SCOPUS Database
This study aimed to identify the research gaps on the theme "Municipal Solid Waste Management", as from the analysis of articles indexed in the SCOPUS database. For this objective to be achieved, an applied research of exploratory nature and qualitative approach was carried out. It is noteworthy that, as method and technical procedures were adopted, respectively, the bibliographic research and the literature review. The data used in the analysis were obtained from the SCOPUS database in May 2018 and treated using Microsoft Excel® software. It is noteworthy that as a selection criterion, thirty papers indexed in this base that presented the highest number of citations were analyzed. As main results, it can be highlighted that the identified gaps were grouped into eight categories. Among the categories analyzed, one can highlight life cycle assessment, with ten gaps, and tools for municipal solid waste management, with eight. It is also noteworthy that the category "municipal solid waste management associated with other methodologies" occupies the second position, along with "tools for the management of municipal solid waste, indicating the lack of studies in the highlighted areas and pointing out the relevance of the theme for the academic environ
European HYdropedological Data Inventory (EU-HYDI)
There is a common need for reliable hydropedological information in Europe. In the last decades research institutes, universities and government agencies have developed local, regional and national datasets containing soil physical, chemical, hydrological and taxonomic information often combined with land use and landform data. A hydrological database for western European soils was also created in the mid-1990s. However, a comprehensive European hydropedological database, with possible additional information on chemical parameters and land use is still missing.
A comprehensive joint European hydropedological inventory can serve multiple purposes, including scientific research, modelling and application of models on different geographical scales.
The objective of the joint effort of the participants is to establish the European Hydropedological Data Inventory (EU-HYDI). This database holds data from European soils focusing on soil physical, chemical and hydrological properties. It also contains information on geographical location, soil classification and land use/cover at the time of sampling. It was assembled with the aim of encompassing the soil variability in Europe. It contains data from 18 countries with contributions from 29 institutions. This report presents an overview of the database, details the individual contributed datasets and explains the quality assurance and harmonization process that lead to the final database
Albumin Administration in Patients with Severe Sepsis Due to Secondary Peritonitis
BackgroundTo determine whether or not intravenous administration of human albumin can reduce mortality in patients with severe sepsis due to secondary peritonitis.MethodsAdult patients who were admitted to the surgical intensive care unit (SICU) who fulfilled the criteria of severe sepsis due to secondary peritonitis were consecutively included in this retrospective study. Patients who received and those who did not receive at least a daily minimum of 25 g intravenous human albumin for 3 days during their first 7 days of SICU admission were classified as the study group and control group, respectively.ResultsA total of 133 patients were included in this study. For patients with baseline serum albumin ≤ 20 g/L, 28-day mortality was significantly lower in the study group. For patients with baseline serum albumin > 20 g/L, albumin administration had no significant effects on 28-day mortality.ConclusionFor patients with severe sepsis due to secondary peritonitis, albumin administration may reduce 28-day mortality in patients whose baseline serum albumin is ≤ 20 g/L, but no such effect was found in patients whose baseline serum albumin was > 20 g/L
Soil biochemistry and microbial activity in vineyards under conventional and organic management at Northeast Brazil.
The São Francisco Submedium Valley is located at the Brazilian semiarid region and is an important center for irrigated fruit growing. This region is responsible for 97% of the national exportation of table grapes, including seedless grapes. Based on the fact that orgThe São Francisco Submedium Valley is located at the Brazilian semiarid region and is an important center for irrigated fruit growing. This region is responsible for 97% of the national exportation of table grapes, including seedless grapes. Based on the fact that organic fertilization can improve soil quality, we compared the effects of conventional and organic soil management on microbial activity and mycorrhization of seedless grape crops. We measured glomerospores number, most probable number (MPN) of propagules, richness of arbuscular mycorrhizal fungi (AMF) species, AMF root colonization, EE-BRSP production, carbon microbial biomass (C-MB), microbial respiration, fluorescein diacetate hydrolytic activity (FDA) and metabolic coefficient (qCO2). The organic management led to an increase in all variables with the exception of EE-BRSP and qCO2. Mycorrhizal colonization increased from 4.7% in conventional crops to 15.9% in organic crops. Spore number ranged from 4.1 to 12.4 per 50 g-1 soil in both management systems. The most probable number of AMF propagules increased from 79 cm-3 soil in the conventional system to 110 cm-3 soil in the organic system. Microbial carbon, CO2 emission, and FDA activity were increased by 100 to 200% in the organic crop. Thirteen species of AMF were identified, the majority in the organic cultivation system. Acaulospora excavata, Entrophospora infrequens, Glomus sp.3 and Scutellospora sp. were found only in the organically managed crop. S. gregaria was found only in the conventional crop. Organically managed vineyards increased mycorrhization and general soil microbial activity
Depletion of thiols leads to redox deregulation, production of 4-hydroxinonenal and sperm senescence: a possible role for GSH regulation in spermatozoa
[EN] We hypothesized that thiols and particularly glutathione (GSH) are essential for the regulation of stallion sperm functionality. To test this hypothesis, we initially investigated the relationship between sperm function and GSH content, revealing highly significant correlations between GSH, sperm viability, motility, and velocity parameters (P < 0.001). Furthermore, the deleterious effects of GSH depletion using menadione and 1,3 dimethoxy 1,4, naphtoquinone (DMNQ) were able to be prevented by the addition of cysteine, but no other antioxidant. Pre-incubation with cysteine prevented menadione and DMNQ induced damage to sperm membranes after 1 h (P < 0.001; P < 0.05) and after 3 h of incubation (P < 0.001, P < 0.05). Pre-incubation with cysteine ameliorated both the menadione- and DMNQ-induced increase in 4-hydroxynonenal (P < 0.001). As cysteine is a precursor of GSH, we hypothesized that stallion spermatozoa are able to synthesize this tripeptide using exogenous cysteine. To test this hypothesis, we investigated the presence of two enzymes required to synthesize GSH (GSH and GCLC) and using western blotting and immunocytochemistry we detected both enzymes in stallion spermatozoa. The inhibition of GCLC reduced the recovery of GSH by addition of cysteine after depletion, suggesting that stallion spermatozoa may use exogenous cysteine to regulate GSH. Other findings supporting this hypothesis were changes in sperm functionality after BSO treatment and changes in GSH and GSSG validated using HPLC-MS, showing that BSO prevented the increase in GSH in the presence of cysteine, although important stallion to stallion variability occurred and suggested differences in expression of glutamate cysteine ligase. Mean concentration of GSH in stallion spermatozoa was 8.2 ± 2.1 μM/109 spermatozoa, well above the nanomolar ranges per billion spermatozoa reported for other mammals.SIThe authors received financial support for this study from the Ministerio de Economía y Competitividad-FEDER, Madrid, Spain, grants AGL2013-43211-R, AGL2017-83149-R Junta de Extremadura-FEDER (European Regional Development Fund) (GR 18008 and IB16030). PMM is supported by a pre-doctoral grant from the Ministerio de Educación, Cultura y Deporte, Madrid Spain FPU13/03991. COF is supported by a post-doctoral grant from the Ministerio de Economía y Competitividad “Juan de la Cierva” IJCI-2014-21671, JMO-R holds a PhD grant from Valhondo Calaaf Foundation, Cáceres Spain
Phytotoxicity of alkaloids, coumarins and flavonoids isolated from 11 species belonging to the Rutaceae and Meliaceae families
Meliaceae and Rutaceae families are known for the high diversity of their secondary metabolites, which include many groups that represent a rich source of structural diversity, and are good candidates as sources of allelochemicals that could be useful in agriculture. In the work described here the bioactivity profiles were evaluated for 3 alkaloids (1–3), 12 coumarins (4–15), 2 phenylpropanoic acid derivatives (16 and 17) and 14 flavonoids (18–31) from 11 species belonging to the Meliaceae and Rutaceae families. All compounds were tested in the wheat coleoptile bioassay and those that showed the highest activities were tested on the STS (Standard Target Species) Lepidium sativum (cress), Lactuca sativa (lettuce), Lycopersicon esculentum (tomato), and Allium cepa (onion). Most of the isolated compounds showed phytotoxic activity and graveoline (3), psoralen (8), and flavone (18) were the most active, with bioactivity levels similar to that of the commercial herbicide Logran1. The results indicate that these compounds could be involved as semiochemicals in the allelopathic interactions of these plant species
Bovine colostrum: a source of bioactive compounds for prevention and treatment of gastrointestinal disorders.
Bovine colostrum is a rich source of nutrients and biologically active molecules known to be able to modulate the human immune system, such as lactoferrin, lysozyme, lactoperoxidase, immunoglobulins and growth factors. This comprehensive review aimed to gather evidence from animal experimentation and clinical trials that investigated the potential effects of bovine colostrum in preventing and treating diseases that affect the human gastrointestinal tract. Considered safe for human consumption, BC or its isolate components were used against a range of different gastrointestinal disorders. Beneficial effects were observed in several conditions: gastrointes-tinal infections, infectious diarrhoea, drug-induced lesions, gut-barrier malfunction, and inflammatory bowel disease. Under proper processing to maintain its components' integrity, BC products are valuable supplements with high nutraceutical value, capable of promoting and restoring gastrointestinal health
DIRECT trial. Diverticulitis recurrences or continuing symptoms: Operative versus conservative Treatment. A MULTICENTER RANDOMISED CLINICAL TRIAL
Background: Persisting abdominal complaints are common after an episode of diverticulitis treated conservatively. Furthermore, some patients develop frequent recurrences. These two groups of patients suffer greatly from their disease, as shown by impaired health related quality of life and increased costs due to multiple specialist consultations, pain medication and productivity losses. Both conservative and operative management of patients with persisting abdominal complaints after an episode of diverticulitis and/or frequently recurring diverticulitis are applied. However, direct comparison by a randomised controlled trial is necessary to determine which is superior in relieving symptoms, optimising health related quality of life, minimising costs and preventing diverticulitis recurrences against acceptable morbidity and mortality associated with surgery or the occurrence of a complicated recurrence after conservative management. We, therefore, constructed a randomised clinical trial comparing these two treatment strategies. Methods/design: The DIRECT trial is a multicenter randomised clinical trial. Patients (18-75 years) presenting themselves with persisting abdominal complaints after an episode of diverticulitis and/or three or more recurrences within 2 years will be included and randomised. Patients randomised for conservative treatment are treated according to the current daily practice (antibiotics, analgetics and/or expectant management). Patients randomised for elective resection will undergo an elective resection of the affected colon segment. Preferably, a laparoscopic approach is used. The primary outcome is health related quality of life measured by the Gastro-intestinal Quality of Life Index, Short-Form 36, EQ-5D and a visual analogue scale for pain quantification. Secondary endpoints are morbidity, mortality and total costs. The total follow-u
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