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1.
FGFR–TACC, found in different tumor types, is characterized by the fusion of a member of fibroblast grown factor receptor (FGFR) tyrosine kinase (TK) family to a member of the transforming acidic coiled-coil (TACC) proteins. Because chromosome numerical alterations, hallmarks of FGFR–TACC fusions are present in many hematological disorders and there are no data on the prevalence, we studied a series of patients with acute myeloid leukemia and myelodysplastic syndrome who presented numerical alterations using cytogenetic traditional analysis. None of the analyzed samples showed FGFR3–TACC3 gene fusion, so screening for this mutation at diagnosis is not recommended.  相似文献   
2.
3.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
4.
Tenocytes represent a valuable source of cells for the purposes of tendon tissue engineering and regenerative medicine and as such, should possess a high degree of tenogenic differentiation prior to their use in vivo in order to achieve maximal efficacy. In the current report, we identify an efficient means by which to maintain differentiated tenocytes in vitro by employing the hanging drop technique in combination with defined growth media supplements. Equine tenocytes retained a more differentiated state when cultured as scaffold-free microtissue spheroids in low serum-containing medium supplemented with l-ascorbic acid 2-phosphate, insulin and transforming growth factor (TGF)-β1. This was made evident by significant increases in the expression levels of pro-tenogenic markers collagen type I (COL1A2), collagen type III (COL3A1), scleraxis (SCX) and tenomodulin (TNMD), as well as by enhanced levels of collagen type I and tenomodulin protein. Furthermore, tenocytes cultured under these conditions demonstrated a typical spindle-like morphology and when embedded in collagen gels, became highly aligned with respect to the orientation of the collagen structure following their migration out from the microtissue spheroids. Our findings therefore provide evidence to support the use of a biomimetic microtissue approach to culturing tenocytes and that in combination with the defined growth media described, can improve their differentiation status and functional repopulation of collagen matrix.  相似文献   
5.
Entering the postmodern world in which society is confronting crossroads, paradoxes, and complexity, the health care system is encountering a transformation more comprehensive and revolutionary than has ever been seen before. Analysis of the state of nursing vis a vis these transformations indicates that the current paradigm does not ensure the existence of the profession in the postmodern health care system. That is because of increased difficulties in consolidating the economic and quality issues into the core of nursing, and in understanding the complexity inherent in health related situations.  相似文献   
6.
The transforming growth factors type beta 1, beta 2, and beta 1.2 suppress multidrug transport in human pat-1 glioblastoma cells and even in cells that strongly over-express mdr genes and are resistant to inhibition of multidrug transport by chemosensitizers. Thus, inhibition of multidrug transport by cytokines might be a new approach to increase cellular accumulation of chemotherapeutic agents in multidrug resistant glial tumor cells. Interestingly, a member of the more distantly related decapentaplegic subgroup of transforming growth factors, the bone morphogenetic protein BMP 2, did not inhibit multidrug transport.  相似文献   
7.
BACKGROUND: Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the antifibrotic mechanisms of relaxin on renal fibroblasts in vitro. METHODS: Rat cortical fibroblasts were obtained from outgrowth culture of renal tissue isolated from kidneys 3 days post-unilateral ureteric obstruction and constituted 100% of cells studied. A relaxin radio-receptor assay was used to establish binding of relaxin to renal fibroblasts in vitro. Functional studies then examined the effects of H2 relaxin (0, 1, 10 and 100 ng/ml) on fibroblast kinetics, expression of alpha-smooth muscle actin (alpha-SMA), total collagen synthesis, collagenase production and collagen-I lattice contraction. CTGF mRNA expression was also measured by northern analysis. RESULTS: H2 relaxin bound with high affinity to rat renal fibroblasts, but receptor numbers were low. Consistent with its previously reported bimodal effect, transforming growth factor (TGF-beta 1) reduced fibroblast proliferation, an effect abrogated by H2 relaxin. Fibroblasts exposed to H2 relaxin (100 ng/ml) for 24 h demonstrated decreased immunostaining for alpha-SMA and reduced alpha-SMA protein expression compared with controls. There was a trend for a relaxin-mediated reduction in total collagen synthesis and alpha 1(I) mRNA expression with large dose-related increases in collagenase protein expression being observed. TGF-beta 1-stimulated collagen-I lattice contraction was significantly inhibited following co-incubation with 100 ng/ml relaxin. Incremental doses of H2 relaxin had no significant effect on CTGF mRNA expression. CONCLUSIONS: The findings of this study suggest that the antifibrotic effects of relaxin involve down-regulation of fibroblast activity, increase in collagenase synthesis and restructuring of collagen-I lattices, which are consistent with its known physiological role of matrix remodelling. Although there appears to be an interaction between TGF-beta 1 and H2 relaxin, this does not appear to involve a reduction in CTGF mRNA expression.  相似文献   
8.
目的研究转化生长因子β1(TGFβ1)、胶原纤维和网状纤维在肝硬化组织中的分布、意义及肝细胞癌变对其分布的影响.方法采用免疫组织化学SP法检测30例肝硬化组织和1例大致正常肝组织TGFβ1的表达情况.用Masson染色显示胶原纤维,Gordon-Sweet染色显示网状纤维.CMIAS-8彩色图像分析系统对阳性目标进行分析处理.结果 (1)TGFβ1主要位于肝非实质细胞胞浆内,这些细胞主要分布在汇管区、纤维间隔、炎症区;纤维组织中有少量TGFβ1存在;少数肝细胞胞浆内也表达TGFβ1,总阳性率为20%,肝炎肝硬化组TGFβ1阳性表达率与肝炎肝硬化合并原发性肝细胞癌组比较无显著性差异(P>0.05);(2)肝炎肝硬化组TGFβ1的IOD为395.3±291.3,胶原纤维的AD为(6.3±3.8)%,网状纤维的AD为(5.4±2.3)%.TGFβ1的IOD与胶原纤维的AD呈正相关(r=0.8991,P<0.01),与网状纤维的AD呈正相关(r=0.8317,P<0.01);肝炎肝硬化合并原发性肝细胞癌组TGFβ1 的IOD为840.7±449.6,胶原纤维的AD为(12.5±4.9)%,网状纤维的AD为(9.2±3.2)%.TGFβ1的IOD与胶原纤维的AD呈正相关(r=0.8025,P<0.01),与网状纤维的AD无相关(r=0.4314,P>0. 05).肝炎肝硬化组TGFβ1的表达、胶原纤维和网状纤维分布与肝炎肝硬化合并原发性肝细胞癌组比较均有显著性差异(P均<0.01);(3)胶原纤维主要分布在汇管区、纤维隔,炎症区,肝窦旁也可见少量存在;网状纤维主要分布在汇管区、纤维隔、炎症区、肝窦旁、实质细胞周围;原发性肝癌及外周肝硬化组织Gordon-Sweet染色显示肝癌细胞区网状纤维不显色.结论 TGFβ1与肝纤维化肝硬化的发生发展密切相关.在肝炎肝硬化,TGFβ1表达增强,当合并原发性肝细胞癌时,TGFβ1有极强表达;TGFβ1可作为原发性肝细胞癌的血清学辅助诊断,Gordon-Sweet染色可作为原发性肝细胞癌的病理学辅助诊断.  相似文献   
9.
BACKGROUND: Most of our knowledge concerning obstructive uropathy has been derived mainly from surgically manipulated animal models, and the pathogenesis of congenital obstructive hydronephrosis is not fully elucidated. Nitric oxide (NO) acts as an important biological modulator with diverse physiological functions, which can be either toxic or protective depending on the situation. NO is synthesized from l-arginine by nitric oxide synthase, and in the kidney iNOS is expressed spontaneously. The aim of our study is to investigate the expression of iNOS protein and its relationship with tubulointerstitial fibrosis and tubular cell apoptosis in congenital hydronephrosis. METHODS: We conducted histological studies on 18 kidneys of six-week-old-rats from an inbred colony of congenital hydronephrosis with reference to the histological grading of the affected kidney, tubulointerstitial fibrosis, renal tubular atrophy, and tubular cell apoptosis. Renal transforming growth factor-beta1 (TGF-beta1) level was determined by a sandwich ELISA assay and the expression of iNOS was analyzed by western blotting. RESULTS: Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. Renal TGF-beta1 level was higher in hydronephrotic kidneys than normal control kidneys (364.81 +/- 52.60 vs. 221.19 +/- 22.53 pg/mg protein, P < 0.05). Tubular apoptotic score in hydronephrotic kidneys was also significantly higher than in the normal control kidneys (1.97 +/- 0.42 vs. 0.14 +/- 0.02/HPF, P < 0.01). The expression of iNOS protein was lower in the affected kidneys compared with the normal control kidneys (8.79 +/- 0.78 vs. 14.00 +/- 0.83 arbitrary unit, P < 0.01). There was a negative correlation between iNOS expression and histological grading in congenital hydronephrosis. The iNOS expression also correlated negatively with renal interstitial fibrosis, TGF-beta1 level and tubular cell apoptosis. CONCLUSION: Our study confirmed the down-regulation of iNOS expression in affected kidneys from rats with congenital hydronephrosis, in which the cytoprotective effect of NO may be lost or weakened.  相似文献   
10.
目的 探讨Decorin抑制结膜下瘢痕形成的作用机制并为临床应用提供理论依据。方法 新西兰大白兔分为Decorin组、磷酸盐缓冲液 (PBS)组、正常对照组。在滤过术后第 7,14,3 0天 ,应用链酶亲和素免疫组织化学法 (SABC法 )检测各组在结膜滤过泡中转化生长因子 - β1(TGF- β1)和转化生长因子 - βⅠ型受体 (TGF - βRⅠ )的含量 ;应用天狼星玫瑰红 -偏振光法检测各组Ⅰ、Ⅲ型胶原的含量。 结果 PBS组结膜滤过泡中TGF - β1、TGF - βRⅠ免疫组化染色和Ⅰ、Ⅲ型胶原染色呈强阳性表达 ,第 3 0天明显比第 7天增强 (P <0 .0 5 ) ;Decorin组结膜滤过泡中TGF - β1、TGF - βRⅠ免疫组化染色和Ⅰ、Ⅲ型胶原染色呈弱阳性表达 ,相同时相点比较 ,Decorin组比PBS组明显呈弱表达 (P <0 .0 1)。Decorin可使滤过泡瘢痕中TGF - β1和TGF - βRⅠ活性降低 ,Ⅰ、Ⅲ型胶原的含量减少。 结论 Decorin可作为抑制滤过泡瘢痕形成的辅助药物  相似文献   
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