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61.
62.
The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions.  相似文献   
63.
Reasons for performing study: Autologous cellular therapy products including adipose‐derived stromal vascular fraction (SVF), bone marrow mononuclear cells (BMMNs), cord blood mononuclear cells (CBMNs) and platelet rich plasma are options for treatment of acute orthopaedic lesions while mesenchymal stem cells (MSCs) are culture expanded. These products may contribute to healing by secreting matrix proteins or growth factors, but they may also act on endogenous MSCs to facilitate healing. Objectives: To determine the effects of cell therapy products on MSCs function in vitro. The hypothesis was that cell therapy products promote MSCs functions including proliferation, migration and mediator release. Methods: Fat, bone marrow (BM), cord blood and platelets were obtained from 6 Quarter Horses. The BM‐MSCs and their autologous cell therapy products were co‐incubated in transwells. Mesenchymal stem cells proliferation, migration, gene expression and cytokine concentrations were determined. Results: All cell therapy products increased MSCs proliferation, but SVF induced significantly more proliferation than any other product. Also SVF elicited more MSCs chemotaxis and, along with BMMNs, significantly more MSCs chemoinvasion. Cord blood mononuclear cells stimulated MSCs to produce high concentrations of interleukin‐6 (IL‐6), transforming growth factor‐β1 (TGF‐β1), and prostaglandin E2 (PGE2). Stromal vascular fraction and platelet lysate did not stimulate MSCs but SVF and platelet lysate themselves contained high concentrations of PGE2 and IL‐6 (SVF) and TGF‐β1 (platelet lysate). Conclusions: Autologous cell products variably stimulate MSCs functions with 2 primary patterns apparent. Products either contained preformed mediators that may have intrinsic healing function, or products stimulated MSCs to secrete mediators. Potential relevance: The specific clinical indications for these products may differ to include administration as a sole treatment modality prior to MSCs injection for intrinsic cell and cytokine activity (i.e. SVF) or administration concurrently with MSCs to activate MSCs for treatment of chronic lesions (i.e. CBMNs).  相似文献   
64.
Objective: To determine the effect of storage on ammonia concentration in canine packed red blood cell (pRBC) units.
Design: In vitro and in vivo study.
Setting: University Veterinary Teaching Hospital.
Interventions: Ammonia concentration was measured in 7 units of canine pRBC prepared in citrate-phosphate-dextrose (CPD) and Adsola on Days 1 and 35 of storage. Ammonia was measured in 4 additional units of canine pRBC on Days 0, 7, 14, 21, 28, and 35. Plasma ammonia was also determined in 5 anemic dogs receiving pRBC.
Measurements and Main Results: Ammonia concentration increased from 73 ± 15 mmol/L (mean ± SD) on Day 1 to 800 ± 275 mmpl/L on Day (p<0.001). When measured every 7 days in 4 units of canine pRBC, ammonia concentration increased from 23 ± 8 mmol/L on Day 0 to 179 ± 13 mmol/L (Day 7), 276 ± 56 mmol/L (Day 14). 383 ± 47 mmol/L (Day21), 466 ± 30 mmol/L (Day 28), and 562 ± 27 mmol/L (Day 35) (p<0.05 for all comparisons). In a preliminary study, plasma ammonia concentration measured in blood samples from 5 anemic dogs without primary liver disease immediately before and after transfusion with 5–10 ml/kg of stored pRBC remained in the normal reference range.
Conclusions: The ammonia concentration in stored canine pRBC increased markedly with time. In this preliminary study, ammonia concentrations in dogs without primary liver disease did not increase above the reference range after transfusion with pRBC.  相似文献   
65.
Interstitial cells of Cajal (ICC) have been described in the gastrointestinal tract of different mammals including humans, horses, pigs, rats, dogs, mice and guinea-pigs. In the present study, ICC were identified in the jejunum of Bos taurus using polyclonal anti-c-Kit antibodies in immunohistochemical assays. Vimentin and desmin intermediate filaments were also determined using monoclonal antibodies. ICC were found in the tunica muscularis either in a palisade distribution pattern between the outer longitudinal and the inner circular layers (ICC-MP) or freely distributed in clusters in the longitudinal layer (ICC-LM). Morphometric studies determined that ICC have a fusiform shape presenting cytoplasmic prolongations. ICC were positive to c-Kit and vimentin antigens but negative to desmin. We have observed and described for the first time the presence of ICC in a ruminant. As observed in the aforementioned mammals, bovine ICC were associated with the myenteric plexus. Nevertheless, the presence of widespread ICC in the longitudinal muscular layer of the jejunum differs from previously described studies of other mammals.  相似文献   
66.
Ultrasonographic images were acquired of the mammary glands of 40 bitches with physiologically lactating (n = 20) or inflamed glands (n = 20). Echogenicity, structure, homogeneity, thickness, and distinguishability of each tissue layer were assessed. Additionally, overall echogenicity was noted. In the normal lactating gland, different tissues could be differentiated easily. The parenchyma was, without exception, separated from adjacent tissues and was visible as medium echogenic tissue with a coarse-grained structure. The tissue always had some echogenic lines and anechoic areas and was slightly heterogeneous. The loss of distinct layering of the tissue was characteristic of an inflamed mammary gland and inflamed regions had reduced echogenicity. Additionally in five bitches with mastitis, the ultrasound examination was repeated five times for documentation of the progress of the illness and associated changes, supplemented with a color Doppler sonogram to assess changes in blood vessel density. Information from the examinations carried out via B-mode did not allow treatment success to be predicted. Two bitches with reduced blood vessel density centrally had a poor outcome whereas three bitches with increased blood vessel density had a good outcome. Thus, Doppler sonography might be a useful tool to obtain information of the prognosis in acute canine mastitis.  相似文献   
67.
Supplements produced by mouse testicular cells (mTCs) and the interaction between cells can increase the differentiation rate of human umbilical cord mesenchymal stem cells (hUCMSCs) into the germ-like cells. We studied the differentiation rate of hUCMSCs into the germ-like cells under effect of mTCs co-culturing. Isolated hUCMSCs from postpartum human umbilical cords were cultured. Then, the expression of mesenchymal (CD73, CD90 and CD105) and haematopoietic (CD34 and CD45) markers of hUCMSCs were confirmed by flow cytometry. Then, the hUCMSCs were cultured in four distinct groups: (a) control, (b) co-culture until D0, (c) co-culture until D5 and (d) co-culture until D10, in order to differentiate into the germ-like cells. After 10 days, the expression of OCT4, VASA, Fragilis and SYCP3 genes were examined by Real-Time qPCR. The flow cytometry indicated a high expression of mesenchymal markers and a low expression of haematopoietic markers (CD73:98.6%, CD90: 99.1%, CD105: 99.5%, CD34: 4.22% and CD45: 2.54%). The expression of OCT4 decreased during the time while the expression of VASA, Fragilis and SYCP3 markers increased in the co-culture with testicular cells (p value <.05). Co-culture with mTCs may be used as an effective method to differentiate hUCMSCs into germ-like cells.  相似文献   
68.
试验旨在阐明前列腺素E2(prostaglandin E2,PGE2)和F(prostaglandin F,PGF)对体外培养的奶牛子宫内膜上皮细胞中环氧合酶-1(cyclooxygenase-1,COX-1))与环氧合酶-2(cyclooxygenase-2,COX-2)表达的影响。培养奶牛子宫内膜上皮原代细胞和传代细胞,第4代细胞以1×106个/孔接种于6孔板,以10-7mol/L PGE2和PGF分别预处理细胞24 h,以100 ng/mL细菌脂多糖(lipopolysaccharides,LPS)刺激细胞4、8和12 h后分别提取RNA和总蛋白质,采用实时荧光定量PCR与Western blotting等技术检测COX-1与COX-2 mRNA和蛋白质的表达量。结果表明,与对照组相比,COX-1 mRNA表达量在PGE2单独作用4、8和12 h后显著上调(P<0.05);COX-2 mRNA表达量在PGE2单独作用4和12 h后显著上调(P<0.05),PGE2单独处理使COX-1、COX-2蛋白表达量均显著上调(P<0.05)。与对照组相比,LPS刺激8和12 h时COX-1 mRNA表达量显著下调(P<0.05),LPS刺激后COX-1蛋白表达量无显著变化(P>0.05);LPS刺激后4、8和12 h时COX-2 mRNA表达量显著上调(P<0.05),LPS刺激后COX-2蛋白表达量显著上调(P<0.05)。与LPS单独处理组相比,LPS+PGE2处理组在8和12 h时COX-1和COX-2 mRNA表达量均显著上调(P<0.05),同时COX-1和COX-2蛋白表达量也显著上调(P<0.05)。PGF在LPS未刺激和刺激后对COX-1和COX-2 mRNA的表达无显著影响(P>0.05),仅在PGF单独处理8和12 h后COX-1 mRNA表达量上调(P<0.05)。两种激素联合处理与各自单独处理及LPS单独刺激相比,对COX-1和COX-2 mRNA表达具有一定的协同诱导作用。  相似文献   
69.
piggyBac转座子介导的家蚕细胞转基因研究初探   总被引:1,自引:4,他引:1  
为探讨稳定转化家蚕细胞表达外源基因的新方法,以家蚕核型多角体病毒(BmNPV)极早期蛋白基因(ie-1)启动子元件驱动新霉素抗性基因(neor),并克隆至具有绿色荧光蛋白基因(gfp)标记的昆虫转座子载体piggyBac中,构建转基因载体pigA3-IE-Neo。以该载体转染家蚕BmN细胞,用终浓度800μg/mL的遗传霉素(geneticin,G418)筛选3个月,获得了稳定转化的细胞,呈现绿色荧光的细胞数达80%以上。通过PCR鉴定证实了细胞基因组DNA中neor基因和gfp基因的存在。  相似文献   
70.
为了探究百里香酚对山羊子宫内膜上皮细胞(goat endometrial epithelial cells,g EECs)的毒性作用,采用不同浓度的百里香酚作用于g EECs后,观测其对细胞生长曲线,细胞形态学变化,以及细胞膜结构完整性的影响。结果表明,百里香酚对EECs的毒性作用与其浓度呈剂量依赖效应(y=-0.008x+1.2202,R~2=0.9767),即随着药物浓度的增加细胞的增殖抑制率增大,药物对细胞的半数增殖抑制率(IC50)为100μg/m L。当50、100μg/m L的百里香酚作用于EECs时,g EECs的细胞核、细胞浆的形态均未产生明显变化,但当150μg/m L的百里香酚作用于g EECs时,细胞膜破裂,细胞死亡;而且药物浓度≥100μg/m L时细胞LDH的释放量显著高于正常细胞组,g EECs细胞膜的完整性受到破坏。百里香酚作用于山羊子宫内膜上皮细胞后呈现一定的毒性作用,且毒性作用和药物的浓度有关。百里香酚作用于g EECs的安全范围在0~100μg/m L,研究结果为百里香酚治疗奶牛等经济动物的炎症性疾病的临床用药浓度提供理论依据。  相似文献   
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