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31.
Andressa Dalmazzo João Diego A. Losano Carolina C. Rocha Roberta H. Tsunoda Camilla M. Mendes 《Animal biotechnology》2018,29(3):174-182
Semen cryopreservation is an essential biotechnology in canine reproduction and during the cryopreservation process commonly egg yolk are used. The discrepancy in the egg yolk composition and the potential risk of disease dissemination are obstacles for semen exportation and use. Therefore, studies aiming to substitute egg yolk are extremely important. In this context, soy lecithin contains a low-density lipoprotein fraction, is an interesting alternative. Thus, the objective of this study was to compare extenders based on soy lecithin (several concentrations and forms) with egg yolk during the cryopreservation process of dog sperm. For this purpose, we used twelve dogs. Semen was evaluated at different time points (after refrigeration, glycerolization, and thawing), by motility analysis (CASA) and functional tests (e.g., membrane integrity—eosin/nigrosin, acrosome integrity—fast green/Bengal rose, mitochondrial activity—3’3 diaminobenzidine, Chromatin susceptibility to acid-induced denaturation—SCSA, and susceptibility to oxidative stress—thiobarbituric acid reactive substances). The results indicated that egg yolk and lower concentrations of lecithin had similar effects on mitochondrial activity and motility. Thus, soy lecithin is a potentially viable alternative to egg yolk for the cryopreservation of dog semen. 相似文献
32.
Primary structure of bovine growth hormone 总被引:2,自引:0,他引:2
33.
Vitamin C modulates glutamate transport and NMDA receptor function in the retina 总被引:1,自引:0,他引:1 下载免费PDF全文
Ivan Domith Renato Socodato Camila C. Portugal Andressa F. Munis Aline T. Duarte‐Silva Roberto Paes‐de‐Carvalho 《Journal of neurochemistry》2018,144(4):408-420
34.
35.
Luis V. Portela Andressa W. Brochier Clarissa B. Haas Afonso Kopczynski de Carvalho Jussania A. Gnoato Eduardo R. Zimmer Eduardo Kalinine Luc Pellerin Alexandre P. Muller 《Molecular neurobiology》2017,54(8):5807-5814
Hyperpalatable diets (HP) impair brain metabolism, and regular physical exercise has an apparent opposite effect. Here, we combined a prior long-term exposure to HP diet followed by physical exercise and evaluated the impact on some neuroenergetic components and on cognitive performance. We assessed the extracellular lactate concentration, expression of monocarboxylate transporters (MCTs), pyruvate dehydrogenase (PDH), and mitochondrial function in the hippocampus. Male C57BL/6J mice were fed 4 months with HP or a control diet. Subsequently, they were divided in the following groups: control diet sedentary (CDS), control diet exercise (CDE), HP diet sedentary (HPS), and HP diet exercise (HPE) (n = 15 per group) and were engaged for an additional 30-day period of voluntary exercise and HP diet. Relative to the control situation, exercise increased MCT1, MCT4, and PDH protein levels, while the HP diet increased MCT1 and MCT4 protein levels. The production of hydrogen peroxide (H2O2) and the mitochondrial membrane potential (??m) stimulated by succinate in hippocampal homogenates were not significantly different between groups. ADP phosphorylation and the maximal respiratory rate induced by FCCP showed similar responses between groups, implying a normal mitochondrial function. Also, extracellular brain lactate levels were increased in the HPE group compared to other groups soon after performing the Y-maze task. However, such enhanced lactate levels were not associated with improved memory performance. In summary, hippocampal protein expression levels of MCT1 and 4 were increased by physical exercise and HP diet, whereas PDH was only increased by exercise. These observations indicate that a hippocampal metabolic reprogramming takes place in response to these environmental factors. 相似文献
36.
Elizandra Braganhol Daiane Huppes Andressa Bernardi Márcia Rosângela Wink Guido Lenz Ana Maria Oliveira Battastini 《Cell and tissue research》2009,335(2):331-340
Glioblastoma multiforme is the most common type of primary brain tumour and has the worst clinical outcome. Nucleotides represent
an important class of extracellular molecules involved in cell proliferation, differentiation and apoptosis. Alterations in
purinergic signalling have been implicated in pathological processes, such as cancer, and glioma cell lines are widely employed
as a model to study the biology of brain tumours. Increasing evidence, however, suggests that glioma cell lines may not present
all the phenotypic and genetic characteristics of the primary tumours. We have compared the biological characteristics of
C6 rat glioma cells in culture and the same cells after their implantation in the rat brain and growth in culture (denominated
as the C6 ex vivo culture model). Parameters evaluated included cell morphology, differentiation, angiogenic markers, purinergic receptors
and ecto-nucleotidase mRNA profile/enzymatic activity. Analysis of the C6 glioma cell line and C6 ex vivo glioma cultures revealed distinct cell morphologies, although cell differentiation and angiogenic marker expressions were
similar. Both glioma models co-expressed multiple P2X and P2Y receptor subtypes with some differences. In addition, the C6
glioma cell line and C6 ex vivo glioma cultures exhibited similar extracellular ATP metabolism and cell proliferation behaviour when exposed to cytotoxic
ATP concentrations. Thus, the disruption of purinergic signalling is a feature shown not only by glioma cell lineages, but
also by primary glioma cultures. Our results therefore suggest the participation of the purinergic system in glioma malignancy.
This study was supported by grants from the Brazilian agencies CNPq, FAPERGS and Fundo de Incentivo à Pesquisa e Eventos (HCPA).
E. Braganhol and D. Huppes were recipients of Brazilian CNPq fellowships; A. Bernardi was the recipient of a CAPES fellowship. 相似文献
37.
Dihydroxyacetone (DHA), a three-carbon sugar, is the browning ingredient in commercial sunless tanning formulations. DHA preparations
have been used for more than 50 years and are currently highly popular for producing temporary pigmentation resembling an
ultraviolet-induced tan. In this work, the in vitro antifungal activity of dihydroxyacetone was tested against causative agents
of dermatomycosis, more specifically against dermatophytes and Candida spp. The antifungal activity was determined by the broth microdilution method according to the Clinical and Laboratory Standards Institute guidelines for yeasts and filamentous fungi. The data obtained show that the fungicidal activity varied from 1.6 to 50 mg ml−1. DHA seems to be a promising substance for the treatment of dermatomycosis because it has antifungal properties at the same
concentration used in artificial suntan lotions. Therefore, it is a potential low-toxicity antifungal agent that may be used
topically because of its penetration into the corneal layers of the skin. 相似文献
38.
Milene Mesquita Paola Resende Andressa Marttorelli Viviane Machado Carolina Q. Sacramento Natalia Fintelman-Rodrigues Juliana L. Abrantes Rita Tavares Marcelo Schirmer Marilda M. Siqueira Thiago Moreno L. Souza 《PloS one》2014,9(4)
The 2009 pandemic influenza A(H1N1)pdm09 virus emerged and caused considerable morbidity and mortality in the third world, especially in Brazil. Although circulating strains of A(H1N1)pdm09 are A/California/04/2009-like (CA-04-like) viruses, various studies have suggested that some mutations in the viral hemagglutinin (HA) may be associated with enhanced severity and fatality. This phenomenon is particularly challenging for immunocompromised individuals, such as those who have undergone bone marrow transplant (BMT), because they are more likely to display worse clinical outcomes to influenza infection than non-immunocompromised individuals. We studied the clinical and viral aspects of post-BMT patients with confirmed A(H1N1)pdm09 diagnosis in the largest cancer hospital in Brazil. We found a viral strain with K-15E, P83S and Q293H polymorphisms in the HA, which is presumably more virulent, in these individuals. Despite that, these patients showed only mild symptoms of infection. Our findings complement the discovery of mild cases of infection with the A(H1N1)pdm09 virus with the K-15E, P83S and Q293H mutations in Brazil and oppose other studies that have linked these changes with increased disease severity. These results could be important for a better comprehension of the impact of the pandemic influenza in the context of BMT. 相似文献
39.
The antioxidant activity of β-carotene and oxygenated carotenoids lutein, canthaxanthin, and astaxanthin was investigated
during spontaneous and peroxyl-radical-induced cholesterol oxidation. Cholesterol oxidation, measured as generation of 7-keto-cholesterol
(7-KC), was evaluated in a heterogeneous solution with cholesterol, AAPH, and carotenoids solubilized in tetrahydrofuran and
in water, and in a homogeneous solution of chlorobenzene, with AIBN as a prooxidant. The formation of 7-KC was dependent on
temperature and on cholesterol and prooxidant concentrations. All the carotenoids tested, exhibited significant antioxidant
activity by inhibiting spontaneous, AAPH- and AIBN-induced formation of 7-KC, although the overall order of efficacy of these
compounds was astaxanthin > canthaxanthin > lutein = β-carotene. The finding that carotenoids exert protective effects on
spontaneous and free radical-induced cholesterol oxidation may have important beneficial effects on human health, by limiting
the formation of atheroma and by inhibiting cholesterol oxidation in food processing or storage. 相似文献
40.
Paula H Suss Luiz Guilherme A Capriglione Fabiane Barchiki Lye Miyague Danielle Jackowski Letícia Fracaro Andressa V Schittini Alexandra C Senegaglia Carmen LK Rebelatto Márcia Olandoski Alejandro Correa Paulo RS Brofman 《Experimental biology and medicine (Maywood, N.J.)》2015,240(7):969-978
The development of new therapeutic strategies is necessary to reduce the worldwide social and economic impact of cardiovascular disease, which produces high rates of morbidity and mortality. A therapeutic option that has emerged in the last decade is cell therapy. The aim of this study was to compare the effect of transplanting human umbilical cord-derived stromal cells (UCSCs), human umbilical cord blood-derived endothelial cells (UCBECs) or a combination of these two cell types for the treatment of ischemic cardiomyopathy (IC) in a Wistar rat model. IC was induced by left coronary artery ligation, and baseline echocardiography was performed seven days later. Animals with a left ventricular ejection fraction (LVEF) of ≤40% were selected for the study. On the ninth day after IC was induced, the animals were randomized into the following experimental groups: UCSCs, UCBECs, UCSCs plus UCBECs, or vehicle (control). Thirty days after treatment, an echocardiographic analysis was performed, followed by euthanasia. The animals in all of the cell therapy groups, regardless of the cell type transplanted, had less collagen deposition in their heart tissue and demonstrated a significant improvement in myocardial function after IC. Furthermore, there was a trend of increasing numbers of blood vessels in the infarcted area. The median value of LVEF increased by 7.19% to 11.77%, whereas the control group decreased by 0.24%. These results suggest that UCSCs and UCBECs are promising cells for cellular cardiomyoplasty and can be an effective therapy for improving cardiac function following IC. 相似文献