9,764 research outputs found
Oxidative stress in rheumatoid arthritis: what the future might hold regarding novel biomarkers and add-on therapies
Numerous rheumatologic autoimmune diseases, among which rheumatoid arthritis, are chronic inflammatory diseases capable of inducing multiple cumulative articular and extra-articular damage, if not properly treated. Nevertheless, benign conditions may, similarly, exhibit arthritis as their major clinical finding, but with short-term duration instead, and evolve to spontaneous resolution in a few days to weeks, without permanent articular damage. Such distinction-self-limited arthritis with no need of immunosuppressive treatment or chronic arthritis at early stages?-represents one of the greatest challenges in clinical practice, once many metabolic, endocrine, neoplastic, granulomatous, infectious diseases and other autoimmune conditions may mimic rheumatoid arthritis. Indeed, the diagnosis of rheumatoid arthritis at early stages is a crucial step to a more effective mitigation of the disease-related damage. As a prototype of chronic inflammatory autoimmune disease, rheumatoid arthritis has been linked to oxidative stress, a condition in which the pool of reactive oxygen species increases over time, either by their augmented production, the reduction in antioxidant defenses, or the combination of both, ultimately implying compromise in the redox signaling. The exact mechanisms through which oxidative stress may contribute to the initiation and perpetuation of local (in the articular milieu) and systemic inflammation in rheumatoid arthritis, particularly at early stages, still remain to be determined. Furthermore, the role of antioxidants as therapeutic adjuvants in the control of disease activity seems to be overlooked, as a little number of short studies addressing this issue is currently found. Thus, the present review focuses on the binomial rheumatoid arthritis-oxidative stress, bringing insights into their pathophysiological relationships, as well as the implications of potential diagnostic oxidative stress biomarkers and therapeutic interventions directed to the oxidative status in patients with rheumatoid arthritis
Bibliografia. David Lopes - Nomes árabes de terras portuguesas.
79 (1-2) Jan.-Jun. 1969, p. 77-78
A student-centered approach for developing active learning: the construction of physical models as a teaching tool in medical physiology
BACKGROUND: Teaching physiology, a complex and constantly evolving subject, is not a simple task. A considerable body of knowledge about cognitive processes and teaching and learning methods has accumulated over the years, helping teachers to determine the most efficient way to teach, and highlighting student's active participation as a means to improve learning outcomes. In this context, this paper describes and qualitatively analyzes an experience of a student-centered teaching-learning methodology based on the construction of physiological-physical models, focusing on their possible application in the practice of teaching physiology. METHODS: After having Physiology classes and revising the literature, students, divided in small groups, built physiological-physical models predominantly using low-cost materials, for studying different topics in Physiology. Groups were followed by monitors and guided by teachers during the whole process, finally presenting the results in a Symposium on Integrative Physiology. RESULTS: Along the proposed activities, students were capable of efficiently creating physiological-physical models (118 in total) highly representative of different physiological processes. The implementation of the proposal indicated that students successfully achieved active learning and meaningful learning in Physiology while addressing multiple learning styles. CONCLUSION: The proposed method has proved to be an attractive, accessible and relatively simple approach to facilitate the physiology teaching-learning process, while facing difficulties imposed by recent requirements, especially those relating to the use of experimental animals and professional training guidelines. Finally, students' active participation in the production of knowledge may result in a holistic education, and possibly, better professional practices
Ampliação do período produtivo pela adoção conjunta de cultivares de morangueiro de dias curtos e neutros em sistema de produção orgânica.
Ocorrência e duração de dormência em arroz de terras altas e de várzeas.
Este trabalho teve por objetivo verificar a ocorrência de dormência e sua intensidade, em cultivares de arroz de terras altas e de várzeas recomendadas pela Embrapa Arroz e Feijão e seus parceiros, bem como de algumas linhagens promissoras com possibilidades de serem lançadas pelo programa de melhoramento genético.bitstream/CNPAF/18763/1/pqfoco54.pd
Soybean Biodiesel and Metrology
33 p. : il.ABSTRACT - Biodiesel is a renewable fuel defined as a monoalkyl ester derived from vegetable oils,
animal fats or microbial oils (algae, bacteria and fungi). The conversion of the fats or oils
from these raw materials into biodiesel is possible through enzymatic or chemical reactions,
which the most widely employed and studied is the transesterification reaction, involving
alcohol and a catalyst. Such process converts triacylglycerols into esters of fatty acids
molecules, which present physical-chemical properties and cetane number similar to diesel
(Krawczyk, 1996; Ma & Hanna, 1999; Li et al., 2008; ASTM D6751, 2008; Moser, 2009; Knothe
et al., 2005; Knothe & Steidley, 2005). Complete discussions regarding the need for International Standards, their applications, the
mechanisms for biodiesel obtainment, its chemical and physicochemical properties, and
considerations about the importance of metrology and its influence on biodiesel quality will
be presented in the next sessions of this chapter
Aging increases susceptibility to high fat diet-induced metabolic syndrome in C57BL/6 mice: Improvement in glycemic and lipid profile after antioxidant therapy
Nonalcoholic fatty liver disease (NAFLD) has been considered a novel component of the metabolic syndrome (MetS), with the oxidative stress participating in its progression. This study aimed to evaluate the metabolic profile in young and old mice with MetS, and the effects of apocynin and tempol on glycemic and lipid parameters. Young and old C57BL/6 mice with high fat diet- (HFD-) induced MetS received apocynin and tempol 50 mg·kg(-1)/day in their drinking water for 10 weeks. After HFD, the young group showed elevated fasting glucose, worsened lipid profile in plasma, steatosis, and hepatic lipid peroxidation. Nevertheless, the old group presented significant increase in fasting insulin levels, insulin resistance, plasma and hepatic lipid peroxidation, and pronounced steatosis. The hepatic superoxide dismutase and catalase activity did not differ between the groups. Tempol and apocynin seemed to prevent hepatic lipid deposition in both groups. Furthermore, apocynin improved glucose tolerance and insulin sensitivity in old mice. In summary, old mice are more susceptible to HFD-induced metabolic changes than their young counterparts. Also, the antioxidant therapy improved insulin sensitivity and glucose tolerance, and in addition, apocynin seemed to prevent the HFD-induced hepatic fat deposition, suggesting an important role of oxidative stress in the induction of NAFLD
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