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141.
Arnaud Jabouille Maylis Delugin Rapha?l Pineau Alexandre Dubrac Fabienne Soulet Stéphanie Lhomond Nestor Pallares-Lupon Hervé Prats Andreas Bikfalvi Eric Chevet Christian Touriol Michel Moenner 《Oncotarget》2015,6(28):24922-24934
IRE1α is an endoplasmic reticulum (ER)-resident transmembrane signaling protein and a cellular stress sensor. The protein harbors a cytosolic dual kinase/endoribonuclease activity required for adaptive responses to micro-environmental changes. In an orthotopic xenograft model of human glioma, invalidation of IRE1α RNase or/and kinase activities generated tumors with remarkably distinct phenotypes. Contrasting with the extensive angiogenesis observed in tumors derived from control cells, the double kinase/RNase invalidation reprogrammed mesenchymal differentiation of cancer cells and produced avascular and infiltrative glioblastomas with blood vessel co-option. In comparison, selective invalidation of IRE1α RNase did not compromise tumor angiogenesis but still elicited invasive features and vessel co-option. In vitro, IRE1α RNase deficient cells were also endowed with a higher ability to migrate. Constitutive activation of both enzymes led to wild-type-like lesions. The presence of IRE1α, but not its RNase activity, is therefore required for glioblastoma neovascularization, whereas invasion results only from RNase inhibition. In this model, two key mechanisms of tumor progression and cancer cell survival are functionally linked to IRE1α. 相似文献
142.
Tanise Vendruscolo Dalmolin Andreza Francisco Martins Alexandre Prehn Zavascki Daiana de Lima-Morales Afonso Luís Barth 《Diagnostic microbiology and infectious disease》2018,90(2):132-133
We identified one clinical isolate of K. pneumoniae harboring the mcr 1 (plasmid of IncX4 family) and blaKPC-2 (plasmid of IncFIB family) genes in southern Brazil. These findings highlight that K. pneumoniae isolates carrying both mcr-1 and blaKPC-2 may emergence as a serious threat to antimicrobial therapy. 相似文献
143.
Stéphane Terry Ihsan Y. El-Sayed Damien Destouches Pascale Maillé Nathalie Nicolaiew Guillaume Ploussard Fannie Semprez Cynthia Pimpie Himisha Beltran Arturo Londono-Vallejo Yves Allory Alexandre de la Taille David S. Salomon Francis Vacherot 《Oncotarget》2015,6(14):11994-12008
Members of the EGF-CFC (Cripto, FRL-1, Cryptic) protein family are increasingly recognized as key mediators of cell movement and cell differentiation during vertebrate embryogenesis. The founding member of this protein family, CRIPTO, is overexpressed in various human carcinomas. Yet, the biological role of CRIPTO in this setting remains unclear. Here, we find CRIPTO expression as especially high in a subgroup of primary prostate carcinomas with poorer outcome, wherein resides cancer cell clones with mesenchymal traits. Experimental studies in PCa models showed that one notable function of CRIPTO expression in prostate carcinoma cells may be to augment PI3K/AKT and FGFR1 signaling, which promotes epithelial-mesenchymal transition and sustains a mesenchymal state. In the observed signaling events, FGFR1 appears to function parallel to AKT, and the two pathways act cooperatively to enhance migratory, invasive and transformation properties specifically in the CRIPTO overexpressing cells. Collectively, these findings suggest a novel molecular network, involving CRIPTO, AKT, and FGFR signaling, in favor of the emergence of mesenchymal-like cancer cells during the development of aggressive prostate tumors. 相似文献
144.
Influence of Oxynitrided Surface in the Production of a Less Susceptible Titanium Surface to Skin‐Borne Bacterial Adhesion
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Michelle de Medeiros Aires Janine Treter Danilo Cavalcante Braz Cristiano Krug Alexandre José Macedo Clodomiro Alves Júnior 《Artificial organs》2016,40(5):521-526
There is a growing quest for an ideal biomaterial that shows appropriate cellular response and is not susceptible to microbial adhesion. In this study, commercial grade II titanium was submitted to RF/DC plasma surface modification at 2.2 mbar, using gas mixtures of argon, nitrogen, and oxygen at proportions 4:1:2 and 4:1:3. The surfaces were physically and chemically characterized. In order to evaluate bacterial response, the surfaces were exposed to Staphylococcus epidermidis. Oxynitrided samples, although having a higher roughness as compared with untreated samples, exhibited lower bacterial growth. This observation is probably due to the formation of different crystalline phases of nitrides and oxides caused by plasma treatment. The surface with highest contact angle and highest surface tension showed lower bacterial adhesion. These results were confirmed by scanning electron microscopy. The role of nitrogen in reducing bacterial adhesion is clear when this material is compared with untreated titanium, on which only an oxide film is present. 相似文献
145.
Kássio Duan Albani Willian Mauricio Radavelli João Ricardo de Souza Rhayana K. Grosskopf Josue Pires Topazio Leandro Sâmia Lopes Julcemar Dias Kessler Alexandre Alberto Tonin Diego de Córdova Cucco Aleksandro Schafer Da Silva 《Comparative clinical pathology》2014,23(2):475-476
Parasitic diseases affecting goats are able to cause major economic losses, standing out, among them, the lice infestation. According to the literature, lice can act as vectors of other diseases, including the ones caused by blood protozoan. In this sense, this survey study aimed to assess the ectoparasites of goats in the west region of Santa Catarina (SC). Two hundred seventeen goats from 24 different rural properties located in 17 towns in SC were examined. From them, ectoparasites were collected and evaluated in laboratory, where the parasitological classification was performed. In 13 properties, it was possible to identify ectoparasites. Damalinia caprae lice were observed in 126 animals (58 %), while Linognathus stenopsis were found in 10 animals (4.6 %). It is noteworthy that, in these properties, all the animals were under lice parasitism, independent of sex or age. The goats had peeling skin, particularly in the back region (lumbar). All of the 24 properties evaluated were reported having problems with lice in different seasons of the year, even under regular treatment with cypermethrin (spraying). Based on our findings, it was possible to conclude that D. caprae is the major ectoparasite of goats in the investigated area. 相似文献
146.
Tatiana L. Fonseca Joao Pedro Werneck-De-Castro Melany Castillo Barbara M.L.C. Bocco Gustavo W. Fernandes Elizabeth A. McAninch Daniele L. Ignacio Caio C.S. Moises Alexandre Ferreira Balázs Gereben Antonio C. Bianco 《Diabetes》2014,63(5):1594-1604
Type 2 deiodinase (D2) converts the prohormone thyroxine (T4) to the metabolically active molecule 3,5,3′-triiodothyronine (T3), but its global inactivation unexpectedly lowers the respiratory exchange rate (respiratory quotient [RQ]) and decreases food intake. Here we used FloxD2 mice to generate systemically euthyroid fat-specific (FAT), astrocyte-specific (ASTRO), or skeletal-muscle-specific (SKM) D2 knockout (D2KO) mice that were monitored continuously. The ASTRO-D2KO mice also exhibited lower diurnal RQ and greater contribution of fatty acid oxidation to energy expenditure, but no differences in food intake were observed. In contrast, the FAT-D2KO mouse exhibited sustained (24 h) increase in RQ values, increased food intake, tolerance to glucose, and sensitivity to insulin, all supporting greater contribution of carbohydrate oxidation to energy expenditure. Furthermore, FAT-D2KO animals that were kept on a high-fat diet for 8 weeks gained more body weight and fat, indicating impaired brown adipose tissue (BAT) thermogenesis and/or inability to oxidize the fat excess. Acclimatization of FAT-D2KO mice at thermoneutrality dissipated both features of this phenotype. Muscle D2 does not seem to play a significant metabolic role given that SKM-D2KO animals exhibited no phenotype. The present findings are unique in that they were obtained in systemically euthyroid animals, revealing that brain D2 plays a dominant albeit indirect role in fatty acid oxidation via its sympathetic control of BAT activity. D2-generated T3 in BAT accelerates fatty acid oxidation and protects against diet-induced obesity. 相似文献
147.
148.
149.
Paula Grippa Sant’Ana Sabrina Setembre Batah Patrícia Santos Leão Walcy Rosolia Teodoro Sérgio Luiz Borges de Souza Gustavo Augusto Ferreira Mota Danielle Fernandes Vileigas Vitor Loureiro da Silva Dijon Henrique Salomé de Campos Katashi Okoshi Vera Luiza Capelozzi Antonio Carlos Cicogna Alexandre Todorovic Fabro 《Pathophysiology》2018,25(4):373-379
Cardiac remodeling (CR) is a structural change of the heart due to chronic hemodynamic overload related to changes in both myocyte and extracellular matrix (ECM). We investigated that the imbalance of collagen V promotes cardiomyocyte apoptosis that contributes to heart failure and cell death. Aortic stenosis was induced surgically and male Wistar rats were randomized to 18 weeks (Sham 18?w, n?=?12; AoS 18?w, n?=?12) and severe of heart failure (Sham HF, n?=?12; AoS HF, n?=?12) groups. Functional and structural echocardiogram, immunohistochemistry for Ki-67, TUNEL assay and Immunofluorescence for collagen were performed. Our main results were: (1) Progressive reduction of cardiac functional capacity due to cardiac remodeling with decreased eject fraction in heart failure; (2) Imbalance of collagen deposition with increased, crowded and irregular collagen I in situ expression; (3) Dysregulation of dynamic control of collagen fibers with exposed epitopes of collagen V; (4) Additional apoptosis that are dependent to cardiac injury. The collagen V expression in cardiac remodeling is for the first time described and may be related to additional apoptosis and autoimmune response. Our findings suggest a critical role of collagen V in cardiac remodeling to modulate and promote heart failure and death. 相似文献
150.
Bruno F. Fernandes James Coates Alexandre N. Odashiro Carlos Quezada Aimee Huynh Patricia R. Odashiro Macanori Odashiro Miguel N. Burnier Jr. 《Pathology oncology research : POR》2014,20(3):557-563
In order to better understand the role of HIF-1α in the proliferation of the retinoblastoma cells, a siRNA knockdown of HIF-1α followed by a proliferation assay was performed. Further sequencing was then carried out in order to assess knockdown efficiency and expression of HIF-1α. Upregulation of HIF-1α gene expression in CoCl2-treated retinoblastoma cells was demonstrated via melting curve analysis from PCR tests and was further analyzed using western blot and densitometry analysis. Reduction of HIF-1α expression in retinoblastoma, post HIF-1α knockdown, was observed after siRNA transfection into Y-79 cells. Knockdown of HIF-1α resulted in a significant decrease in proliferation thereby demonstrating that HIF-1α is involved in promoting survival and proliferation in retinoblastoma cells. Stabilization of HIF-1α in retinoblastoma cells using CoCl2 was unsuccessful. 相似文献