247 research outputs found
Peritoneal fluid modulates the sperm acrosomal exocytosis induced by N-acetylglucosaminyl neoglycoprotein
The effect of peritoneal fluid (PF) on the human sperm acrosome reaction (AR) was tested. Sperm was pre-incubated with PF and the AR was induced by calcium ionophore A23187 and a neoglycoprotein bearing N-acetylglycosamine residues (NGP). The AR induced by calcium ionophore was inhibited 40% by PF from controls (PFc) and 50% by PF from the endometriosis (PFe) group, but not by PF from infertile patients without endometriosis (PFi). No significant differences were found in the spontaneous AR. When the AR was induced by NGP, pre-incubation with PFc reduced (60%) the percentage of AR, while PFe and PFi caused no significant differences. The average rates of acrosome reactions obtained in control, NGP- and ionophore-treated sperm showed that NGP-induced exocytosis differed significantly between the PFc (11%) and PFe/PFi groups (17%), and the ionophore-induced AR was higher for PFi (33%) than PFc/PFe (25%). The incidence of the NGP-induced AR was reduced in the first hour of pre-incubation with PFc and remained nearly constant throughout 4 h of incubation. The present data indicate that PF possesses a protective factor which prevents premature AR.Hospital de Clínicas de Porto AlegreUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL
Aqueous biphasic systems composed of ionic liquids: one-step extraction/concentration techniques for water pollution tracers
Emergent micropollutants have become a serious global problem with a large impact in the environment and
human health, while their presence in aquatic systems has been registered as ranging from ng/L-1 to ug/L-1.
Pharmaceuticals are ubiquitous micropollutants since their continuous consumption and consequent release via
human excretions into aqueous systems are inevitable. Due to their usually low concentrations in aqueous
samples, the development of a pre-concentration technique in order to continuously quantify and to monitor these
components in aqueous streams is of major relevance.
Aqueous biphasic systems (ABS) composed of ionic liquids (ILs) can be seen as more sustainable separation
processes since they avoid the use of volatile and hazardous organic solvents (VOCs). As liquid-liquid
systems, ABS can be used as extraction, purification and concentration platforms. Due to the outstanding tunable
properties of ILs, IL-based ABS provide higher and more selective extraction efficiencies for a wide range of
compounds when compared to traditional polymer-based ABS. IL-based ABS were already employed and
adequately characterized for the extraction and concentration of endocrine disruptors, either from biological fluids
or aqueous matrices. The aim of this work is to demonstrate the applicability of IL-based ABS to completely
extract and concentrate, in one-step, two different and representative pharmaceutical pollution tracers, namely
caffeine (CAF) and carbamazepine (CBZ). The low concentration of these persistent pollutants (usually found in
ug/L-1 and ng/L-1 levels) does not allow a proper detection and quantification by conventional analytical
equipment without a previous concentration step. However, pre-concentration methods commonly applied are
costly, time-consuming, provide irregular recoveries and/or use VOCs. In this work, ABS composed of the IL
tetrabutylammonium chloride ([N4444]Cl) and the salt K3C6H5O7 was investigated, demonstrating to be able to
completely extract and concentrate CAF and CBZ in a single-step. Moreover, with this pre-treatment step it was
demonstrated to be possible to overcome the detection limits of a high performance liquid chromatography
coupled to an UV-Vis detector equipment. The results obtained demonstrate that IL-based ABS are
versatile pre-concentration techniques, and can be used for the extraction and concentration of a large plethora of
other micropollutants from environmental aqueous matrices.publishe
Strategies of research in the study of cognition: the case of false memories
Title, abstract and keywords provided in EnglishEste artigo pretende apresentar e discutir duas estratégias de pesquisa no âmbito dos estudos da cognição,
relacionando-as ao tema da experiência cognitiva. No que se refere à primeira estratégia, denominada Representacional,
procuraremos analisar, do ponto de vista epistemológico, como duas tradições diferentes da psicologia,
o behaviorismo e o cognitivismo, por se apoiarem ambas nessa estratégia, não incluíram até muito recentemente
em seus estudos a dimensão de experiência dos processos cognitivos. A segunda estratégia, designada Enativa,
se diferencia da primeira pelo entendimento de que a cognição é um ato de criação de si e de mundo, ou seja,
uma emergência coetânea de um mundo próprio e do sujeito que o experimenta. Por fim, objetivamos demonstrar
nossa análise através do estudo de caso do fenômeno das falsas lembranças.This article intends to present and to discuss two research strategies in the ambit of the studies of the cognition,
relating them to the subject of the cognitive experience. As for the first strategy, denominated Representational, we
will try to analyze, from the epistemological point of view, as two different traditions in Psychology, the behaviorism
and the cognitivism, by standing both in this strategy, they didn’t include until very recently in their studies
the dimension of the cognitive processes experience. The second strategy, designated Enactive, differs from the
first by the understanding that the cognition is a creation act of itself and of world, in other words, a simultaneous
emergency of an own world and of the subject who experiments it. Finally, we objectify to demonstrate our
analysis through the case study of the phenomenon of false memories
Portrait of Transcriptional Expression Profiles Displayed by Different Glioblastoma Cell Lines
A contribuição da Embrapa Recursos Genéticos e Biotecnologia à capacitação e formação profissional para implantação do Sistema da Qualidade.
bitstream/CENARGEN-2010/31510/1/ct080.pd
O Processo de Acreditação da Embrapa Recursos Genéticos e Biotecnologia nas Normas NBR ISO/IEC 17.025 e Boas Práticas de Laboratório.
bitstream/CENARGEN-2010/31508/1/ct079.pd
Leukocyte Counts, Myeloperoxidase, and Pregnancy-Associated Plasma Protein A as Biomarkers for Cardiovascular Disease: Towards a Multi-Biomarker Approach
We evaluated leukocyte counts and levels of CRP, fibrinogen, MPO, and PAPP-A in patients with stable and unstable angina pectoris, acute myocardial infarction, and healthy controls. All biomarkers were analyzed again after 6 months. Leukocyte counts and concentrations of fibrinogen, CRP, MPO, and PAPP-A were significantly increased in patients with acute myocardial infarction. Leukocyte counts and concentrations of MPO were significantly increased in patients with unstable angina pectoris compared with controls. After 6 months, leukocyte counts and MPO concentrations were still increased in patients with acute myocardial infarction when compared to controls. Discriminant analysis showed that leukocyte counts, MPO, and PAPP-A concentrations classified study group designation for acute coronary events correctly in 83% of the cases. In conclusion, combined assessment of leukocyte counts, MPO, and PAPP-A was able to correctly classify acute coronary events, suggesting that this could be a promising panel for a multibiomarker approach to assess cardiovascular risk
Chrysin-Loaded Microemulsion: Formulation Design, Evaluation and Antihyperalgesic Activity in Mice
Chrysin is a bioactive flavonoid found in pollens, passion flowers, honey, royal jelly, and propolis, which is commonly used as an ingredient in natural food supplements and is primarily re-sponsible for their pharmacological properties. A transparent chrysin-loaded microemulsion (CS-ME) prepared through a ternary phase diagram was evaluated for use as an antihyperalgesic formulation. It was formulated with 40% Labrasol\uae (surfactant), 5% isopropyl myristate (oil phase) and 55% water (aqueous phase) and classified as an oil-in-water (O/W) microsized system (74.4 \ub1 15.8 nm). Its negative Zeta potential ( 1216.1 \ub1 1.9 mV) was confirmed by polarized light microscopy and dynamic light scattering analysis. In vitro studies in Franz-type static diffusion cells showed that chrysin release from CS-ME followed zero-order kinetics. Oral administration of CS-ME in mice resulted in a statistically significantly reduction (p < 0.05) in carrageenan-induced mechanical hyperalgesia compared to the control group. Treatment with CS-ME also showed anti-inflammatory activity by significantly decreasing the TNF-\u3b1 level (p < 0.01) and increasing that of IL-10 (p < 0.05) compared to the control group. These results suggest that the proposed microsystem is a promising vector for the release of chrysin, being able to improve its capacity to modulate inflammatory and nociceptive responses
Multivariate classification techniques and mass spectrometry as a tool in the screening of patients with fibromyalgia
Abstract: Fibromyalgia is a rheumatological disorder that causes chronic pain and other symptomatic conditions such as depression and anxiety. Despite its relevance, the disease still presents a complex diagnosis where the doctor needs to have a correct clinical interpretation of the symptoms. In this context, it is valid to study tools that assist in the screening of this disease, using chemical work techniques such as mass spectroscopy. In this study, an analytical method is proposed to detect individuals with fibromyalgia (n = 20, 10 control samples and 10 samples with fibromyalgia) from blood plasma samples analyzed by mass spectrometry with paper spray ionization and subsequent multivariate classification of the spectral data (unsupervised and supervised), in addition to the treatment of selected variables with possible associations with metabolomics. Exploratory analysis with principal component analysis (PCA) and supervised analysis with successive projections algorithm with linear discriminant analysis (SPA-LDA) showed satisfactory results with 100% accuracy for sample prediction in both groups. This demonstrates that this combination of techniques can be used as a simple, reliable and fast tool in the development of clinical diagnosis of Fibromyalgia
Variabilidade genética de genótipos de limão ‘tahiti’ cultivados no distrito federal utilizando marcadores RAPD.
A fruticultura é uma atividade que vem crescendo no Distrito Federal, destacando-se o cultivo de lima ácida ‘tahiti’ (Citrus Latifolia Tanaka). A lima ácida ‘tahiti’, conhecida como limão ‘Tahiti’, destaca-se, no Brasil, como uma das frutas cítricas de maior importância comercial e vêm se destacando no Distrito Federal por ser uma atividade rentável, desempenhando grande importância social e econômica na região com predominância de pequenos produtores que trabalham com a produção no período de entressafra. Segundo dados do IBGE, a área plantada com limão ‘tahiti’ no Distrito Federal em 2008 era de 248 hectares, cujo valor da produção foi estimado em R$ 3.632.000,00. O uso de marcadores RAPD têm sido amplamente utilizados para estudos genéticos em citros (MORELL et al., 1995; MACHADO et al., 1996; CRISTOFANI, 1996; COLETTA FILHO et al., 1998, BASTIANEL et al, 1998), permitindo comparar os materiais genéticos ao nível molecular, sem influência do ambiente ou idade e tipo do tecido (FERREIRA & GRATTAPAGLIA, 1995). Neste trabalho, objetivou-se, analisar e quantificar a variabilidade genética entre genótipos de limão ‘tahiti’ cultivados no Distrito Federal, incluindo acessos selecionados em trabalhos de melhoramento visando à seleção de materiais com maior capacidade produtiva durante o período de entressafra
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