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981.
Flávia de Souza Bastos Estevam Barbosa de Las Casas Sergio Martinez Oller 《Computer methods in biomechanics and biomedical engineering》2013,16(5):495-503
The knowledge of contact forces in teeth surfaces during mastication or para-functional movements can help to understand processes related to friction and wear of human dental enamel. The development of a numerical model for analysis of the occlusal contact between two antagonistic teeth is proposed, which includes three basic steps: the characterisation of the surface roughness, its homogenisation using an assumed distribution function and the numerical determination of the resulting forces. Finite element strain results for the main different asperities are statistically combined, deriving the predicted macroscopic behaviour of the interface. Axisymmetric and 3D numerical models with an elasto-plastic constitutive law are used to simulate micro-indentations and micro-contacts, respectively. The contact is allowed to occur locally in planes not necessarily parallel to the surface's mean plane, a problem for which there is no analytical solution. The three identified parameters, homogenised surface hardness (3.68 GPa), surface yield stress (3.08 GPa) and static friction coefficient (0.23), agree with the experimental values reported in the literature. 相似文献
982.
Cecília Bittencourt Severo Aline Gehlen Dall Bello Flávio de Mattos Oliveira Luciana Silva Guazzelli Rogério Tregnago Marlene Haas Bruno Hochhegger Luiz Carlos Severo 《Mycopathologia》2013,175(3-4):323-330
Paracoccidioidomycosis (PCM) is an endemic disease restricted geographically to Latin America. Brazil accounts for about 80 % of the reported cases, and lungs are most frequently affected. A suggestive radiograph of PCM may only be seen late in the course of the disease. At the beginning, it mimics tuberculosis. On the other hand, pleural effusion on rare occasions has been reported in PCM. For this reason, we report two cases with such uncommon manifestation. Our first patient presented pleural effusion probably caused by PCM (a previously unreported cause of lung mass accompanied by effusion); the second with proved pleural effusion due to PCM. A systematic review of the literature was done. 相似文献
983.
Stana Helena Giorgi Grosso Maria Lucia Hirata Katayama Rosimeire Aparecida Roela Suely Nonogaki Fernando Augusto Soares Helena Brentani Leandro Lima Maria Aparecida Azevedo Koike Folgueira Angela Flávia Logullo Waitzberg Fátima Solange Pasini João Carlos Guedes Sampaio Góes M. Mitzi Brentani 《Cell and tissue research》2013,352(3):671-684
Rapamycin is a selective inhibitor of the mammalian target of rapamycin (mTOR), a regulator kinase that integrates growth factors signaling via the phosphoinositide-3-kinase pathway and that has emerged as a novel therapeutic modality in breast cancer (BC). We propose a pre-clinical “ex-vivo” personalized organotypic culture of BC that preserves the microenvironment to evaluate rapamycin-mediated gene expression changes. Freshly excised ductal invasive BC slices, 400 μm thick (n=30), were cultured in the presence or absence (control) of rapamycin (20 nM) for 24 h. Some slices were formalin-fixed for immunohistochemical determinations and some were processed for microarray analysis. Control slices in culture retained their tissue morphology and tissue viability (detected by BrdU uptake). The percentage of proliferating cells (assessed by Ki67) did not change up to 24 h of treatment. Immunohistochemical evaluation of p-AKT, p-mTOR, p-4EBP1 and p-S6K1 indicated that AKT/mTOR pathway activation was maintained during cultivation. For microarray analysis, slices were divided into two groups, according to the presence/absence of epidermal growth factor receptor-type 2 and analyzed separately. Limited overlap was seen among differentially expressed genes after treatment (P<0.01) in both groups suggesting different responses to rapamycin between these BC subtypes. Ontology analysis indicated that genes involved in biosynthetic processes were commonly reduced by rapamycin. Our network analysis suggested that concerted expression of these genes might distinguish controls from treated slices. Thus, breast carcinoma slices constitute a suitable physiological tool to evaluate the short-term effects of rapamycin on the gene profile of individual BC samples. 相似文献
984.
Julia G. A. Vieira Alexandra P. Krüger Tiago Scheuneumann Amanda M. Garcez Maira C. Morais Flávio R. M. Garcia Dori E. Nava Daniel Bernardi 《Journal of Applied Entomology》2020,144(10):857-865
The aim of this study was to evaluate the effect of temperature (10, 15, 20, 25, 30 and 35°C), on the development time and life-time fecundity of Trichopria anastrephae Lima, 1940 (Hymenoptera: Diapriidae) parasitizing Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae). D. suzukii pupae that were up to 24-hr old were submitted to T. anastrephae parasitism for 24 hr. They were placed in plastic containers (50 ml) (ten pupae per container) in climatic chambers at temperatures of 10, 15, 20, 25, 30 and 35°C ± 1°C with a relative humidity of 70% ± 10% and a 12 hr photoperiod. For the adult phase, T. anastrephae couples that were up to 24 hr old were each placed in plastic cages (300 ml) and kept at the same temperatures cited above until their deaths. The higher numbers of parasitism and offspring production were obtained at temperatures between 15 and 25ºC. At the temperatures of 10 and 35ºC, there was no emergence of individuals. The lower thermal threshold (Tt) for the egg to adult period was ≈ 14.6°C for males and females with thermal constants (K) of 384.61 and 432.90, respectively. In terms of the fertility life table, T. anastrephae at 20 and 25°C presented shorter generation time (T) and higher net reproductive rates (Ro) in relation to other temperatures. The data show the ability of T. anastrephae to adapt to different thermal conditions, which is important for biological control programmes of D. suzukii. 相似文献
985.
986.
Flávia Nunes Costa Diego Alex Mayer Alexsandra Valério Janaina de Souza Lima Antônio Augusto Ulson de Souza 《Biocatalysis and Biotransformation》2020,38(5):385-391
AbstractTextile industries account for two-thirds of the total dyestuff market been responsible for the production of a large volume of effluent with unfixed dye. Aromatic dyes as potassium indigo-trisulfonate dye (PIT) are characterized as a chemically stable and complex molecule with high heat and light stability and with high toxicity even at low concentration. In order to evaluate an environmentally friendly method to remove potassium indigo-trisulfonate dye from aqueous solution, a commercial peroxidase (horseradish peroxidase, HPR) was used in the experimental and the data were modelled by the Arrhenius equation. According to the results, the best reaction conditions were obtained using 80?mg.L?1 of dye concentration, 45?°C, pH 5.0, 349.35?U.mL?1, and 4.5?mM hydrogen peroxide concentration leading to a 96% of dye discolouration. 相似文献
987.
988.
Diversification with gene flow and niche divergence in a lizard species along the South American “diagonal of open formations” 下载免费PDF全文
989.
Michele Siqueira Daniel Francis Diego Gisbert Flávia Carvalho Alcantara Gomes Joice Stipursky 《Molecular neurobiology》2018,55(5):3660-3675
Neuroangiogenesis in the developing central nervous system is controlled by interactions between endothelial cells (ECs) and radial glia (RG) neural stem cells, although RG-derived molecules implicated in these events are not fully known. Here, we investigated the role of RG-secreted TGF-β1, in angiogenesis in the developing cerebral cortex. By isolation of murine microcapillary brain endothelial cells (MBECs), we demonstrate that conditioned medium from RG cultures (RG-CM) promoted MBEC migration and formation of vessel-like structures in vitro, in a TGF-β1-dependent manner. These events were followed by endothelial regulation of GPR124 and BAI-1 gene expression by RG-CM. Proteome profile of RG-CM identified angiogenesis-related molecules IGFBP2/3, osteopontin, endostatin, SDF1, fractalkine, TIMP1/4, Ang-1, pentraxin3, and Cyr61, some of them modulated by TGF-β1 induction. In vivo gain and loss of function assays targeting RG cells demonstrates a specific TGF-β1-dependent control of blood vessels branching in the cerebral cortex. Together, our results point to TGF-β1 signaling pathway as a potential mediator of the RG-EC interactions and shed light to the key role of RG in paving the brain vascular network. 相似文献
990.
de Oliveira Marcos Roberto de Souza Izabel Cristina Custódio Brasil Flávia Bittencourt 《Neurochemical research》2021,46(3):482-493
Neurochemical Research - Emodin (EM; 1,3,8-trihydroxy-6-methylanthracene-9,10-dione; C15H10O5) is an anthraquinone and exerts cytoprotective effects, as observed in both in vitro and in vivo... 相似文献