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131.
Rosana de Almeida Santos Karina Dutra Asensi Julia Helena Oliveira de Barros Rafael Campos Silva de Menezes Ingrid Rosenburg Cordeiro Jos Marques de Brito Neto Tais Hanae Kasai-Brunswick Regina Coeli dos Santos Goldenberg 《International journal of molecular sciences》2020,21(24)
Several therapies are being developed to increase blood circulation in ischemic tissues. Despite bone marrow-derived mesenchymal stromal cells (bmMSC) are still the most studied, an interesting and less invasive MSC source is the menstrual blood, which has shown great angiogenic capabilities. Therefore, the aim of this study was to evaluate the angiogenic properties of menstrual blood-derived mesenchymal stromal cells (mbMSC) in vitro and in vivo and compared to bmMSC. MSC’s intrinsic angiogenic capacity was assessed by sprouting and migration assays. mbMSC presented higher invasion and longer sprouts in 3D culture. Additionally, both MSC-spheroids showed cells expressing CD31. mbMSC and bmMSC were able to migrate after scratch wound in vitro, nonetheless, only mbMSC demonstrated ability to engraft in the chick embryo, migrating to perivascular, perineural, and chondrogenic regions. In order to study the paracrine effects, mbMSC and bmMSC conditioned mediums were capable of stimulating HUVEC’s tube-like formation and migration. Both cells expressed VEGF-A and FGF2. Meanwhile, PDGF-B was expressed exclusively in mbMSC. Our results indicated that mbMSC and bmMSC presented a promising angiogenic potential. However, mbMSC seems to have additional advantages since it can be obtained by non-invasive procedure and expresses PDGF-B, an important molecule for vascular formation and remodeling. 相似文献
132.
The ERG1 gene of Saccharomyces cerevisiae encodes squalene epoxidase, a key enzyme in the ergosterol pathway. ERG1 is an essential gene. Disruption of the gene with URA3 results in a lethal phenotype when cells are grown under aerobic conditions, even in the presence of ergosterol. However, cells are viable in the presence of ergosterol under anaerobic growth conditions during which ergosterol is taken up by cells. Physical and genetic mapping data reveal that ERG1 is located on the right arm of chromosome VII proximal to QCR9 at a distance of 14·6 cM from ADE3. 相似文献
133.
Davidson Karina W.; Kupfer David J.; Kaplan Robert M. 《Canadian Metallurgical Quarterly》2007,26(5):519
Science proceeds, directly or indirectly, by consensus. Obtaining scientific consensus proactively when investigating the impact of depression on cardiovascular disease has been daunting, as the professions interested in this area include health psychology, psychiatry, cardiology, epidemiology, and others. Whereas consensus is at times difficult when sought within one specialty, it is almost inconceivable when attempted across disciplines. Therefore, we applaud a new trend, as the National Heart, Lung, and Blood Institute recently called for a working group to provide recommendations on the assessment and treatment of depression in patients with cardiovascular disease. The publication of this working group's report signals two important landmark accomplishments. First, it offers concrete recommendations for researchers interested in contributing to this field. Second, and perhaps more important, the publication of this report signifies a process through which interdisciplinary research areas can be proactive in fostering scientific consensus. Health psychology, an area and a field of research that is naturally interdisciplinary, may be one of the key benefactors of joining and creating stronger consensus processes for this type of science. Whether health psychologists will play a role in creating opportunities to promote consensus in areas of scientific interest remains to be seen. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
A central bias in spatial selection has been proposed to explain the decreasing search efficiency with increasing target eccentricity that results when distractors can occur closer to fixation than the target (J. M. Wolfe, P. O'Neill, & S. C. Bennett, 1998). The authors found evidence for such a bias using an odd-man-out variant of conjunction search. However, the bias was absent for the same displays when the identity of the odd-man-out target was known in advance. The authors propose that (a) top-down knowledge of a target feature supports grouping on this feature and (b) grouping links a peripheral target to central distractors expressing the same feature, increasing the attentional weighting afforded to the target and, consequently, facilitating its detection. The effects are independent of bottom-up priming effects occurring across trials. Thus, feature-based grouping can be driven top-down and can overrule the central bias in spatial selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
Aisha S.G. Stumpf Carlos P. Bergmann Juliane Vicenzi Rebecca Fetter Karina S. Mundstock 《Materials & Design》2009,30(10):4348-4359
This study investigates the mechanical properties of alumina-feldspar based ceramics when exposed to an aggressive environment (acetic acid 4%). Alumina ceramics containing different concentrations of feldspar (0%, 1%, 5%, 10%, or 40%) were sintered at either 1300, 1600, or 1700 °C. Flaws (of width 0%, 30%, or 50%) were introduced into the specimens using a saw. Half of these ceramic bodies were exposed to acetic acid. Their flexural strength, KIC, and porosity were measured and the fractured samples were evaluated using scanning electronic- and optical microscopy. It was found that in the ceramic bodies sintered at 1600 °C, feldspar content up to 10% improved flexural strength and KIC, and reduced porosities. Generally, it was found that acetic acid had a weakening effect on the flexural strength of samples sintered at 1700 °C but a beneficial effect on KIC of ceramics sintered at 1600 °C. It was concluded that alumina-based ceramics with feldspar content up to 10% and sintered at higher temperatures would perform better in an aggressive environment similar to oral cavity. 相似文献
136.
The Middle Dutch Arthurian romance Roman van Walewein (Romanceof Gawain) is attributed in the text itself to two authors,Penninc and Vostaert. Very little quantitative research intothis dual authorship has been done. This article describes ourprogress in applying different non-traditional authorship attributionmethods to the text of Walewein. After providing an introductionto the romance and an overview of earlier research, we evaluateprevious statements on authorship and stylistics by applyingboth Yule's measure of lexical richness and Burrows's Delta.To find out whether these new methods would confirm or evenenhance our present knowledge about the differences betweenthe two authors, we applied an adapted version of John Burrows'sDelta procedure. The adapted version seems to be able to distinguishthe double authorship of the romance. It also helps us to confirmsome and to reject other earlier statements about the positionin the text where the second author started his work. 相似文献
137.
The scope of this study is the assessment of the efficiency of solar disinfection by heterogeneous photocatalysis with sol-gel immobilized (titanium dioxide) TiO2 films over glass cylinders. The solar disinfection process known as SODIS was considered as a reference. Spring water naturally polluted with coliform bacteria was exposed to sunlight in plastic bottles with and without TiO2 over simple solar collectors and the disinfection effectiveness was measured. Total and fecal coliforms quantification was performed by means of the chromogenic substrate method in order to obtain the efficiency of each disinfection treatment. The disinfection with TiO2 was more efficient than the SODIS process, inactivating total coliforms as well as fecal coliforms. On a sunny day (more than 1000 W m(-2) irradiance), it took the disinfection with immobilized TiO2 15 min of irradiation to inactivate the fecal coliforms to make them undetectable. For inactivation of total coliforms, 30 min was required, so that in less than half the time it takes SODIS, the treated water complies with the microbial standards for drinking water in Mexico. Another important part of this study has been to determine the bacterial regrowth in water after the disinfection processes were tested. After SODIS, bacterial regrowth of coliforms was observed. In contrast, when using the TiO2 catalyst, coliforms regrowth was not detected, neither for total nor for fecal coliforms. The disinfection process using TiO2 kept treated water free of coliforms at least for seven days after sun irradiation. This demonstration opens the possibility of application of this simple method in rural areas of developing countries. 相似文献
138.
139.
The sustainability of the second-generation biofuels requests to confirm that the energy produced from lignocellulosic biomass is significantly greater than the energy consumed in the process. As lignocellulosic biomass does not affect the food supply, sugarcane bagasse was analyzed as a raw material for second-generation biofuels production. Exergy analysis serves as a unified and effective tool to evaluate the global process efficiency. Exergy analysis evaluates the performance of sugarcane bagasse and its sustainability in the bioethanol production process. In this work, four ethanol production topologies using the typical daily amount of residual biomass produced by the sugar industry were compared. The exergy analysis concept is effective in screening design alternatives with the lowest environmental impact for second-generation bioethanol fuel production from renewable resources. This study was executed by the use of the Aspen Plus® program and other software developed by the authors. 相似文献
140.
Lech Rak Karina Knapik Jacek Bania Jakub Sujkowski Adam Gadzinowski 《European Food Research and Technology》2014,239(2):189-194
To allow detection of meat from the most popular game species in Poland, we developed a PCR-based method for identification of roe deer (Capreolus capreolus), red deer (Cervus elaphus), and hare (Lepus europaeus). The designed primers were based on the noncoding, mitochondrial D-loop region. Amplicon sizes ranged from 116 to 255 bp. The primers exhibited no cross-reactivity with the DNA from common slaughter and other game species. The detection limit of the assay was established to be below 0.001 % in raw red deer (C. elaphus) and hare (L. europaeus) meat, and below 0.01 % in raw roe deer (C. capreolus) meat, whereas <0.5 % of hare and red deer meat in processed samples could be detected. The PCR-based assay was used for authentication of 17 samples of raw game meat and 32 samples of game meat-containing products available in Polish markets. Analysis of all tested raw meat and processed products revealed the presence of DNA of investigated species in concordance with producers’ declarations. 相似文献