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81.
Bone marrow multipotent stromal cells (BMSCs) have the ability to transdifferentiate into various cell types, including: osteoblasts, chondrocytes, adipocytes, neurons, and cardiomyocytes. This study aimed to differentiate the BMSCs into cardiomyocyte. BMSCs were exposed to 5-azacytidine for 24 h. Seven days after the induction of cell differentiation by 5-azacytidine, the cardiomyogenic cells were stained by fushin and binucleated cells were counted and compared with the neonate cardiomyocyte as positive control. In addition, immunofluorescence analysis and western blot were performed using the antibodies against α-actinin, desmin, troponin T, and β-myosin heavy chain. Our results showed that there was no significant difference between the number of binucleated cells within the cardiomyogenic cell group and positive control group; however, a statistically significant difference was observed between both of these groups and undifferentiated cell group (P < 0.005). In addition, after 5-azacytidine treatment, BMSCs had a higher expression of cardiac-specific markers such as desmin, α-actinin, troponin T and β-myosin heavy chain compared with the untreated groups (P < 0.005). We concluded that 5-azacytidine is an effective inducer for the differentiation of BMSCs into cardiomyocytes and could produce a population of binucleated cells, which express α-actinin, desmin, troponin T, and β-myosin heavy chain, four markers of cardiomyocytes.  相似文献   
82.
The cell therapy of damaged tissue, which is linked to hypoxia condition might fail, in large part due to the emergence of oxidative stress (OS) and/or mitochondrial dysfunctions. Thus, the invigoration of stem cells against oxidative stress could be a reliable strategy to improve the cell therapy outcome. Of various antioxidants, mito-Tempo (mito-T) is one of the potent antioxidants that could target and neutralize the mitochondrial oxidative stress. In this study, for the induction of hypoxia and oxidative stress in mitochondria of the mesenchymal stem cells (MSCs) isolated from human adipose tissue, antimycin A (AMA) was used and then several parameters were analyzed, including cell viability and cell cycle arrest of MSCs exposed to AMA, mito-T, antioxidant potential, redox homeostasis, and signaling pathways in MSCs under oxidative stress. Based on our findings, the treated MSCs were found to impose a high resistance to the OS-induced apoptosis, which correlated with the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway required to manage OS. Upon exposure of the MSCs to high oxidative stress conditions using AMA, the cells failed to scavenge. The use of mito-T was found to alleviate the damage induced by oxidative stress through both direct functions of the free radical scavenging and the interplay in terms of cell signaling pathways including the upregulation of the Nrf2 pathway. These findings may pave the way in the stem cell therapy for the hypoxia-mediated tissue damage.  相似文献   
83.
The concentrations of iodine (I) and bromine (Br) were measured by inductively coupled plasma mass spectrometry in the plasma, kidney, heart, liver, and brain of control and thyroparathyroidectomized (TPTX) rats without and with an additional intake of either NaI or NaBr, 0.5 and 5 μmol/kg/d, respectively, for 21 d. In all groups, the highest concentrations of I and Br were found in the plasma. TPTX did not modify the concentrations of I in tissues, but slightly increased Br in plasma (+33%) and kidney (+24%). The additional intake of I with the drink induced an increase of I concentrations in the tissues tested (from 54 to 191%), except brain, both in control and TPTX rats. This additional intake of I also increased Br levels in the plasma of control (+24%) and TPTX rats (+53%). The additional intake of Br with the drink induced an increase of Br levels in all the tested tissues, brain included (from 85 to 284%). The augmentation was higher in the tissues, particularly brain, of TPTX rats than of controls. The increase of Br in brain after an additional intake contrasts with the absence of increase of I given in the same conditions. This difference between I and Br probably results from the smaller radius of Br ion in comparison with I ion radius. In conclusion, TPTX did not modify the distribution of I in the tested tissues, but slightly increased the concentrations of Br in plasma and kidney. Since the additional intake of Br decreased the level of T4 in plasma of TPTX rats, there is a reciprocal enhancing interaction between thyroid insufficiency and Br.  相似文献   
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Infertility is a growing problem worldwide. Currently, in vitro fertilization (IVF) is widely performed to treat infertility. However, a high percentage of IVF cycles fails, due to the poor developmental potential of the retrieved oocyte to generate viable embryos. Fatty acid content of the follicular microenvironment can affect oocyte maturation and the subsequent developmental competence. Saturated and monounsaturated fatty acids are mainly used by follicle components as primary energy sources whereas polyunsaturated fatty acids (PUFAs) play a wide range of roles. A large body of evidence supports the beneficial effects of n-3 PUFAs in prevention, treatment, and amelioration of some pathophysiological conditions including heart diseases, cancer, diabetes, and psychological disorders. Nevertheless, current findings regarding the effects of n-3 PUFAs on reproductive outcomes in general and on oocyte quality more specifically are inconsistent. This review attempts to provide a comprehensive overview of potential molecular mechanisms by which n-3 PUFAs affect oocyte maturation and developmental competence, particularly in the setting of IVF and thereby aims to elucidate the reasons behind current discrepancies around this topic.  相似文献   
86.
This study designed to determine effect of in ovo feeding of folic acid on subsequent growth performance and blood constituents levels in broilers. A total of 1000 fertile broiler eggs were divided into four groups. Control group (1) received no injection. In group 2, eggs received in ovo feeding of distiller water (40 µg). Group 3 received in ovo feeding of folic acid (40 µg). Groups 4 and 5 were similar to Group 3, except eggs injected with 80 and 120 µg of folic acid. All eggs were incubated and after hatch chickens were randomly assigned into their experimental groups. On days 1 and 42 post-hatch, chicken randomly selected and blood constituents, carcass characteristics, food intake, body weight gain and food conversion ratio were determined. According to the results, no significant difference detected on hatchability rate of the in ovo injected eggs (P?>?0.05). Dose dependent increase observed in glucose and folic acid levels in chicken in ovo injected with folic acid on day 1 post hatch (P?=?0.001). Blood glucose, folic acid and phosphorous levels increased (P?=?0.001) while cholesterol, triglyceride, HDL and LDL, calcium and alkaline phosphatase decreased in ovo injected with folic acid on day 42 post hatch (P?=?0.001). Food conversion ratio increased by in ovo injection of the folic acid (P?=?0.001). These results suggest folic acid had positive effects in broiler chicken.  相似文献   
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89.
Flooding stress has negative impact on soybean cultivation as it severely impairs plant growth and development. To examine whether nuclear function is affected in soybean under flooding stress, abundance of nuclear proteins and their mRNA expression were analyzed. Two-day-old soybean seedlings were treated with flooding for 2 days, and nuclear proteins were purified from root tips. Gel-free proteomics analysis identified a total of 39 flooding-responsive proteins, of which abundance of 8 and 31 was increased and decreased, respectively, in soybean root tips. Among these differentially regulated proteins, the mRNA expression levels of five nuclear-localized proteins were further analyzed. The mRNA levels of four proteins, which are splicing factor PWI domain-containing protein, epsilon2-COP, beta-catenin, and clathrin heavy chain decreased under flooding stress, were also down-regulated. In addition, mRNA level of a receptor for activated protein kinase C1(RACK1) was down-regulated, though its protein was accumulated in the soybean nucleus in response to flooding stress. These results suggest that several nuclear-related proteins are decreased at both the protein and mRNA level in the root tips of soybean under flooding stress. Furthermore, RACK1 might have an important role with accumulation in the soybean nucleus under flooding-stress conditions.  相似文献   
90.
Previously, we discovered a series of novel benzodithiazines-dioxides with both antiviral and anticancer activities. In order to design compounds with distinct antiviral properties, we prepared new compounds with modifications on the imidazole and pyrimidine rings. Herein, we present the synthesis and antiviral activity of 8-chloro-2,3-dihydroimidazo[1,2-b][1,4,2]benzodithiazine 5,5-dioxides (22, 23, 30, and 31) and 9-chloro-2,3,4-trihydropyrimido[1,2-b][1,4,2]benzodithiazine 6,6-dioxides (14, 24, 25, and 27). We successfully identified a lead compound with remarkable anti-HIV-1 activity (EC(50)=0.09microM). These compounds showed minimal cytotoxicity and are therefore suitable for antiviral development.  相似文献   
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