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21.
Barbara Maichak de Carvalho Alejandra Vanina Volpedo Cristiano Queiroz Albuquerque Luís Fernando Fvaro 《Zeitschrift fur angewandte Ichthyologie》2019,35(6):1286-1291
Sagitta otoliths are usually formed of calcium carbonate polymorphs as aragonite. The objective of this study was to verify which carbonate polymorph is predominant in the sagitta otolith of Menticirrhus americanus and check whether this pattern remains in otoliths with morphological alterations. Otoliths of M. americanus were obtained from five sites on the southeast‐south coast of Brazil (São Sebastião (SS) 23°45′S–45°24′O, n = 29; Cananéia‐Iguape Estuarine Complex (CI) 25°02′S–47°54′O, n = 30; Paranaguá Estuarine Complex (PEC) 25°28′S–48°20′O, n = 35; Itapoá (IT) 26°07′S–48°36′O, n = 31; Laguna (LA) 28°28′S–48°46′O, n = 13). The characterization of carbonate polymorphs of otoliths was performed through Raman spectroscopy, a photonic and non‐destructive technique that analyzes molecular vibrations induced by laser. We analyzed 138 pairs of M. americanus otoliths, of which eight otoliths from different pairs presented morphological alterations (SS n = 1, CEP n = 5, IT n = 1, LA n = 1). The Raman spectra show that normal otoliths, that is, without morphological alterations, presented only aragonite in their structure. Among the otoliths that presented morphological alterations, the Raman spectra allowed to identify in six otoliths the deposition of aragonite and in only two otoliths the deposition of vaterite (one specimen of the PEC and one of SS). 相似文献
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David García‐Bernal Marta Palomo Carlos M. Martínez Jos E. Milln‐Rivero Ana I. García‐Guilln Miguel Blanquer Maribel Díaz‐Ricart Robert Sackstein Enric Carreras Jose M. Moraleda 《Journal of cellular and molecular medicine》2020,24(14):8031-8044
Allogeneic hematopoietic stem cell transplantation (allo‐HCT) is an effective therapy for the treatment of high‐risk haematological malignant disorders and other life‐threatening haematological and genetic diseases. Acute graft‐versus‐host disease (aGvHD) remains the most frequent cause of non‐relapse mortality following allo‐HCT and limits its extensive clinical application. Current pharmacologic agents used for prophylaxis and treatment of aGvHD are not uniformly successful and have serious secondary side effects. Therefore, more effective and safe prophylaxis and therapy for aGvHD are an unmet clinical need. Defibrotide is a multi‐target drug successfully employed for prophylaxis and treatment of veno‐occlusive disease/sinusoidal obstruction syndrome. Recent preliminary clinical data have suggested some efficacy of defibrotide in the prevention of aGvHD after allo‐HCT. Using a fully MHC‐mismatched murine model of allo‐HCT, we report here that defibrotide, either in prophylaxis or treatment, is effective in preventing T cell and neutrophil infiltration and aGvHD‐associated tissue injury, thus reducing aGvHD incidence and severity, with significantly improved survival after allo‐HCT. Moreover, we performed in vitro mechanistic studies using human cells revealing that defibrotide inhibits leucocyte‐endothelial interactions by down‐regulating expression of key endothelial adhesion molecules involved in leucocyte trafficking. Together, these findings provide evidence that defibrotide may represent an effective and safe clinical alternative for both prophylaxis and treatment of aGvHD after allo‐HCT, paving the way for new therapeutic approaches. 相似文献
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Microbiota niches have space and/or nutrient restrictions, which has led to the coevolution of cooperation, specialisation, and competition within the population. Different animal and environmental niches contain defined resident microbiota that tend to be stable over time and offer protection against undesired intruders. Yet fluxes can occur, which alter the composition of a bacterial population. In humans, the microbiota are now considered a key contributor to maintenance of health and homeostasis, and its alteration leads to dysbiosis. The bacterial type VI secretion system (T6SS) transports proteins into the environment, directly into host cells or can function as an antibacterial weapon by killing surrounding competitors. Upon contact with neighbouring cells, the T6SS fires, delivering a payload of effector proteins. In the absence of an immunity protein, this results in growth inhibition or death of prey leading to a competitive advantage for the attacker. It is becoming apparent that the T6SS has a role in modulating and shaping the microbiota at multiple levels, which is the focus of this review. Discussed here is the T6SS, its role in competition, key examples of its effect upon the microbiota, and future avenues of research. 相似文献
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群落的多样性取决于物种相互共存的能力,以及克服环境胁迫的能力,从而可能扮演一个环境过滤器的角色。生态位分化导致了比种间竞争更强的种内竞争,促进了物种共存。由于胁迫影响相互作用,生态位分化的强度可能沿胁迫作用的梯度发生变化。在有胁迫的栖息地,如沙漠和高山地区,植物的生长形式更加多样化,这表明在环境胁迫下植物具有更强的生态位分化。我们验证了生态位差异和环境过滤作用随着环境胁迫的增加而增强的假设。在墨西哥南部的半干旱草原上,我们沿着水分胁迫梯度在田间种植了6种一年生植物。植物进行三种种植处理:单独种植(没有相互作用),与同种植物为邻(种内相互作用)或与异种植物为邻(种间相互作用)。我们分析了种内与种间竞争的比值是如何沿水分胁迫梯度变化的,以评估水分如何决定生态位分化的强度。我们还测定了水分胁迫是否代表了一种环境过滤作用。我们发现了种内竞争比种间竞争更强,尤其是在水分胁迫更大的情况下。因此,我们的结果表明,除了一个物种外,所有物种至少在部分水分胁迫梯度下存在生态位分化。一些物种受到胁迫的阻碍,而另一些物种可能因为胁迫消除了土壤病原体而受到它的青睐。虽然高强度的生态位分化在环境胁迫下出现的频率略高,但由于我们的物种样本很小,而且这种通用的模式也存在例外,因此需要进一步的研究来确定这是否是自然界普遍存在的现象。 相似文献
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Mayarling Francisca Troncoso Jafet Ortiz-Quintero Valeria Garrido-Moreno Fernanda Sanhueza-Olivares Alejandra Guerrero-Moncayo Mario Chiong Pablo F. Castro Lorena García Luigi Gabrielli Ramón Corbalán Luis Garrido-Olivares Sergio Lavandero 《生物化学与生物物理学报:疾病的分子基础》2021,1867(9):166170
The vascular cellular adhesion molecule-1 (VCAM-1) is a protein that canonically participates in the adhesion and transmigration of leukocytes to the interstitium during inflammation. VCAM-1 expression, together with soluble VCAM-1 (sVCAM-1) induced by the shedding of VCAM-1 by metalloproteinases, have been proposed as biomarkers in immunological diseases, cancer, autoimmune myocarditis, and as predictors of mortality and morbidity in patients with chronic heart failure (HF), endothelial injury in patients with coronary artery disease, and arrhythmias. This revision aims to discuss the role of sVCAM-1 as a biomarker to predict the occurrence, development, and preservation of cardiovascular disease. 相似文献
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Vadell María Victoria Salomone Vanesa Natalia Castesana Paula Soledad Morandeira Natalia Soledad Rubio Alejandra Cardo María Victoria 《EcoHealth》2021,18(2):250-266
EcoHealth - Human health risk in urban areas depends on multiple environmental features. We performed a year-round survey in a highly urbanized district located in temperate Argentina (General San... 相似文献
30.
Y. M. Gómez M. Fernández Diego Rivera Germán Gómez J. E. Bernal 《Russian Journal of Genetics》2013,49(7):737-745
Genetic structure and diversity of 3789 animals of the Brahman breed from 23 Colombian regions were assessed. Considering the Brahman Zebu cattle as a single population, the multilocus test based on the HW equilibrium, shows significant differences (P < 0.001). Genetic characterization made on the cattle population allowed to examine the genetic variability, calculating a H o = 0.6621. Brahman population in Colombia was a small subdivision wthin populations (F it = 0.045), a geographic subdivision almost non-existent or low differentiation (F st = 0.003) and the F is calculated (0.042) indicates no detriment to the variability in the population, despite the narrow mating takes place or there is a force that causes the variability is sustained without inbreeding actually affect the cattle population. The outcomes of multivariate analyses, Bayesian inferences and interindividual genetic distances suggested that there is no genetic sub-structure in the population, because of the high rate of animal migration among regions. 相似文献