大网膜联合组织工程心肌移植改善大鼠心肌梗死后移植细胞的存活

目的 观察大网膜增加组织工程心肌(EHT)血供,改善微环境后对大鼠心肌梗死模型上移植细胞存活的影响.方法 结扎雌性Sprague-Dawley(SD)大鼠左冠状动脉,制作心肌梗死模型.以雄性大鼠骨髓间充质干细胞(MSCs)为种子细胞,种植于共聚乙交酯-丙交酯(poly lactic acid-CO-glycolic ac-id,PLGA)补片上构建EHT.符合心肌梗死标准的动物随机分成网膜EHT组、单纯EHT组、心肌梗死组和假手术组,每组6只鼠.组织工程心肌植入后4周,用TUNEL法检测移植细胞凋亡,标本取材做病理学检查,免疫组化方法检测内皮细胞标志物vWF表达.结果 TONEL检测发现EHT植入后1周网膜EHT组移植细胞凋亡少于单纯EHT组(P<0.05),2周、4周时两组间凋亡无明显差异(P>0.05).vWF染色发现EHT植入后1周、2周、4周网膜EHT组微血管密度均高于单纯EHT组(P<0.05).结论 网膜包裹MSCs-PLGA构建的EHT覆盖于心肌梗死表面后能够通过增加微血管密度,改善局部微环境,减少移植细胞的早期凋亡,促进移植细胞的存活.     

神经慢性卡压后基质金属蛋白酶及其组织抑制物在神经中的表达

目的 观察大鼠坐骨神经慢性卡压后基质金属蛋白酶-9(MMP-9)和金属蛋白酶组织抑制剂( TIMP-1)在神经中的表达.方法 将90只雄性SD大鼠随机分为对照组和卡压组.根据Mackinnon法建立神经慢性卡压模型,采用逆转录-聚合酶链反应(RT-PCR)和免疫组织化学技术检测神经干内MMP-9和TIMP-1的表达.结果 神经慢性卡压2周时神经纤维脱髓鞘;4周时结缔组织增生;12周后神经内纤维分隔进行性增多,神经纤维化.早期,MMP-9和TIMP-1表达增加,MMP-9mRNA在2周达峰值0.0485,TIMP-1 10周达峰值0.1592,MMP-9/TIMP-1明显升高;后期,MMP-9显著降低,TIMP-1继续升高,MMP-9/TIMP-1显著降低.结论 周围神经慢性卡压后神经纤维化,其机制可能与神经中MMP-9/TIMP-1比值早期增高、晚期降低有关.     

组织金属蛋白酶抑制因子-1在胃癌中的表达

目的 探讨组织金属蛋白酶抑制因子－1在胃癌中表达的意义。方法 采用免疫组化S－P法对47例胃癌组织进行TIMP－1的检测。结果 TIMP－1主要表达于胃癌癌周基质细胞，癌细胞少量表达，TIMP－1的表达强度与胃癌患者淋巴结转移（P＜0．01）、浆膜浸润（P＜0．01）、TNM分期（P＜0．05）均相关。结论 TIMP－1可作为判断胃癌恶性行为的重要生物学标记物。     

Autologous porcine heart cell transplantation improved heart function after a myocardial infarction

OBJECTIVE: Fetal cardiomyocyte transplantation improved heart function after cardiac injury. However, cellular allografts were rejected despite cyclosporine (INN: ciclosporin) therapy. We therefore evaluated autologous heart cell transplantation in an adult swine model of a myocardial infarction. METHODS: In 16 adult swine a myocardial infarction was created by occlusion of the distal left anterior descending coronary artery by an intraluminal coil. Four weeks after infarction, technetium 99m-sestamibi single photon emission tomography showed minimal perfusion and viability in the infarcted region. Porcine heart cells were isolated and cultured from the interventricular septum at the time of infarction and grown in vitro for 4 weeks. Through a left thoracotomy, either cells (N = 8) or culture medium (N = 8) was injected into the infarct zone. RESULTS: Four weeks after cell transplantation, technetium 99m-sestamibi single photon emission tomography demonstrated greater wall motion scores in the pigs receiving transplantation than in control animals (P =.01). Pigs receiving transplantation were more likely to have an improvement in perfusion scores (P =.03). Preload recruitable stroke work (P =.009) and end-systolic elastance (P =. 02) were greater in the pigs receiving transplantation than in control animals. Scar areas were not different, but scar thickness was greater (P =.02) in pigs receiving transplantation. Cells labeled with bromodeoxyuridine in vitro could be identified in the infarct zone 4 weeks after transplantation. Swine receiving transplantation gained more weight than control animals (P =.02). CONCLUSION: Autologous porcine heart cell transplantation improved regional perfusion and global ventricular function after a myocardial infarction.     

Expression of matrix metalloproteinase-7 and tissue inhibitor of metalloproteinase-2 in human endometrial carcinoma

<正>Objective:To investigate the expression of matrix metalloproteinase-7(MMP-7) and its tissue inhibitor (TIMP-2) in endometrial carcinoma and analyze their significance in endometrial cancer's invasion and metastasis. Methods:Endometrial tissues were collected from 64 patients with endometrial carcinoma,20 patients with endometrial hyperplasia and 20 normal women.The expressions of MMP-7,TIMP-2 in endometrium were measured by immuohistochemistry. Results;Expressions of MMP-7,TIMP-2 in endometrium of patients with endometrial carcinoma were significantly higher than those in normal endometrium(P0.05).MMP-7 expression increased with surgical-pathological staging,depth of myometrial invasion,histologic grades and lymph node metastasis(P0.05),while TIMP-2 expression was related to lymph node metastasis(P0.05).TIMP-2 expression in endometrial cancer was significantly higher than that in hyperplastic endometrium(P0.05).Expressions of TIMP-2 and MMP-7 in endometrium of patients with endometrial carcinoma were positively correlated(r=0.654,P0.001). Conclusion:Highly expressed MMP-7 and TIMP-2 in endometrium may be related to development,invasion and metastasis of endometrial cancers.     

Caspase-3 inhibition preserves myocardial geometry and long-term function after infarction

BACKGROUND: Cardiac remodeling after infarction is characterized by progressive ventricular dilation and functional impairment. Although surgical and percutaneous revascularization strategies may prevent remodeling, not all patients are candidates for these procedures. Apoptosis in the border-zone myocardium is thought to be critical to the remodeling process, and caspase-3 is a downstream effector of apoptosis. We hypothesized that inhibition of caspase-3 activity might limit dysfunction and remodeling after permanent coronary artery ligation. METHODS: FVB male mice underwent permanent ligation of the left anterior descending coronary artery. Immediately before surgery and for 7 subsequent days, animals were treated daily with 3 mg/kg DEVD-CHO, a cell-permeable inhibitor of caspase-3 (n = 16), or vehicle (n = 28). At 2 weeks and 6 weeks, echocardiography was performed and ventricular dimensions and function were assessed. At 8 weeks, invasive hemodynamic measurements were made and the animals were sacrificed. RESULTS: There was a trend toward improved survival in the inhibitor-treated group compared to the vehicle-treated group (56.3% versus 21.4%, P = 0.07). Infarct size at the time of sacrifice was comparable in both groups. At both 2 and 6 weeks, left ventricular dimensions, including end-diastolic and end-systolic diameters, were less in inhibitor-treated animals. Fractional shortening was higher at 6 weeks in the inhibitor-treated animals (22.1 +/- 6.0% versus 15.0 +/- 6.0%, P = 0.02). Invasive hemodynamic parameters at 8 weeks were comparable, with the exception of diastolic blood pressure, which was less in the inhibitor group. CONCLUSION: Treatment with a caspase-3 inhibitor improved survival and prevented ventricular dilation and dysfunction after permanent coronary artery occlusion.     

Hydrogel-based engineered skeletal muscle grafts normalize heart function early after myocardial infarction

Tissue engineering represents an attractive approach for the treatment of congestive heart failure. The influence of the differentiation of myogenic graft for functional recovery is not defined. We engineered a biodegradable skeletal muscle graft (ESMG) tissue and investigated its functional effect after implantation on the epicardium of an infarcted heart segment. ESMGs were synthesized by mixing collagen (2 mg/mL), Matrigel (2 mg/mL), and rat skeletal muscle cells (10(6)). Qualitative and quantitative aspects of ESMGs were optimized. Two weeks following coronary ligation, the animals were randomized in three groups: ESMG glued to the epicardial surface with fibrin (ESMG, n = 7), fibrin alone (fibrin, n = 5), or sham operation (sham, n = 4). Echocardiography, histology, and immunostaining were performed 4 weeks later. A cohesive three-dimensional tissular structure formed in vitro within 1 week. Myoblasts differentiated into randomly oriented myotubes. Four weeks postimplantation, ESMGs were vascularized and invaded by granulation tissue. Mean fractional shortening (FS) was, however, significantly increased in the ESMG group as compared with preimplantation values (42 +/- 6 vs. 33 +/- 5%, P < 0.05) and reached the values of controlled noninfarcted animals (control, n = 5; 45 +/- 3%; not significant). Pre- and postimplantation FS did not change over these 4 weeks in the sham group and the fibrin-treated animals. This study showed that it is possible to improve systolic heart function following myocardial infarction through implantation of differentiated muscle fibers seeded on a gel-type scaffold despite a low rate of survival.     

Zinc transport by the heart lymphatic system after acute myocardial infarction

Open-chest dog preparations were used to determine divalent cation transport following acute myocardial infarction. Cardiac lymph flow, lymph and plasma protein, zinc, calcium, and magnesium content and hemodynamic measurements were recorded every 20 min before and after coronary artery occlusion in sham operated (N = 4), infarcted (N = 6), and lymph-ablated animals (N = 4). During the 4-hr occlusion period, with constant blood pressure, lymph flow increased from 1.53 ± 0.25 to 2.15 ± 0.44 mg/hr (SEM), P < 0.01. Zinc decreased in plasma from 0.69 ± 0.10 to 0.41 ± 0.08 μg/ml, P < 0.01, and in lymph from 0.69 ± 0.08 to 0.40 ± 0.02 μg/ml, P < 0.01. Zinc to protein ratio decreased similarly to total zinc in plasma and lymph. Changes in calcium and magnesium were insignificant. Lymph to plasma concentration ratios increased for protein from 0.57 ± 0.05 to 0.62 ± 0.02, P < 0.05, and for zinc from 1.10 ± 0.26 to 1.21 ± 0.14, P < 0.05. Heart lymph clearance (lymph:plasma ratio × lymph flow) steadily rose for protein from 0.31 to 0.06 to 0.50 ± 0.08, P < 0.05, and for zinc from 0.59 ± 0.18 to 0.92 ± 0.15, P < 0.05. Lymph and plasma measurements did not change significantly in shamoperated animals. Plasma zinc remained unchanged from baseline after coronary occlusion in all lymphablated animals. The increased clearance of protein and zinc suggests that plasma proteins are zinc carriers after acute myocardial infarction and that the reduction of plasma zinc is dependent upon an intact cardiac lymphatic circulation.     

金属蛋白酶-1和组织金属蛋白酶抑制因子-1在膝关节病理性滑膜皱襞中的表达及意义

目的探讨病理性滑膜皱襞发病机制中对软骨破坏有基质金属蛋白酶的参与。方法关节镜检查确诊为病理性滑膜皱襞和正常滑膜皱襞，分别进行免疫组化染色，观察金属蛋白酶-1（MMP-1）和组织金属蛋白酶抑制因子-1（TIMP-1）的表达及分布。结果MMP-1、TIMP-1在病理性滑膜皱襞和正常皱襞内的阳性表达，差异具有显著性（χ^2=16．014，P=0．000；χ^2=4．059，P=0．044）。MMP-1在滑膜衬里层细胞、单核和淋巴细胞、血管内皮细胞和化生的软骨细胞呈阳性表达，而在正常滑膜皱襞组织中不表达。TIMP-1只在滑膜衬里层细胞和少量的成纤维细胞有表达，而MMP-1免疫组化显示阳性细胞数和着色强度强于TIMP-1。结论病理性滑膜皱襞可产生MMP-1、TIMP-1，而且两者分布不平衡，可能是导致软骨破坏的生物学因素。     

Three-dimension structure of ventricular myocardial fibers after myocardial infarction

Background  

To explore the pathological changes of three-dimension structure of ventricular myocardial fibers after anterior myocardial infarction in dog heart.     

结肠直肠癌病人血浆金属蛋白酶及其组织抑制物的表达及意义

目的：探讨结肠直肠癌病人血浆中基质金属蛋白酶-9（MMP-9）及其组织抑制因子-1（TIMP-1）的表达与结肠直肠癌浸润、转移及预后的关系,以及手术、化疗对其表达的影响,以期在分子水平上更准确地判断结肠直肠癌的预后。方法：选取结肠直肠癌病人50例,于手术前、术后10d、6次化疗后2周,分别抽取病人4mL外周静脉血,采用酶联免疫分析法检测MMP-9、TIMP-1血浆浓度的变化。结果：低分化结肠直肠癌病人血浆MMP-9及TIMP-1水平高于高、中分化者（P〈0．01、P〈0．05）;TNMⅢ、Ⅳ期病人高于TNMⅠ、Ⅱ期者（P〈0．01）。手术后血浆MMP-9、TIMP-1水平显著下降,有统计学意义（P〈0．01、P〈0．05）,化疗后其浓度变化无显著性差异（P〉0．05）。结论：MMP-9和TIMP-1与肿瘤恶性程度有关;术前检测外周血MMP-9和TIMP-1浓度有可能成为结肠直肠癌辅助诊断及病情评估的较好血清学标志。MMP-9可能与肿瘤复发或转移存在一定关系,术后动态检测外周血MMP-9浓度可反映肿瘤负荷。从而对监测肿瘤复发提供一定帮助。     

Angiotensin-converting enzyme (ACE) inhibitor therapy after myocardial infarction in relation to left ventricular function

Objective--To investigate to what extent and by what methods clinicians assess left ventricular (LV) function after an acute myocardial infarction (AMI) and how the results of the assessments relate to the use of angiotensin-converting enzyme (ACE) inhibitors; furthermore, to explore which main indications caused the clinicians to initiate ACE inhibitor therapy. Design--From 16 hospitals we drew a sample of patients who were discharged with the diagnosis of AMI during a 3-month period in 1999/2000. Physicians in each hospital obtained the observed rate of use of cardiovascular drugs at discharge and also information on ejection fraction (EF) measurements. The results of the EF recordings were classified into three categories: &gt;0.50, 0.40-0.50 and &lt;0.40. The clinicians' main indications for drug use were reported. Results--Among 767 patients discharged alive, EF was measured in 409 (53%), by echocardiography in 53% and by radionuclide ventriculography in 47%. Of the 409 patients 227 (55%) had EF &gt;0.50,?95 (24%) EF 0.40-0.50 and 87 (21%) EF &lt;0.40. Adjusted odds ratio for ACE inhibitor therapy being initiated during the AMI was 13.5 for those with EF &lt;0.40 compared with those with EF &gt;0.50. The main indication for starting ACE inhibitor therapy was heart failure (50%) followed by secondary prevention (42%). Conclusion--Measuring EF appears to be an important tool in the evaluation of AMI patients prior to discharge from hospital. Initiation of ACE inhibitor therapy related strongly to the results of the assessments.     

肝门胆管癌基质金属蛋白酶MMP-2及其组织抑制因子TIMP-2表达及意义的研究

目的：探讨基质金属蛋白酶MMP－2及其组织抑制因子TIMP－2在肝门胆管癌的表达及其与肝门胆管癌浸润、转移及预后间的关系。方法：采用免疫组化S－P法对78例肝门胆管癌的MMP－2及其组织抑制因子TIMP－2的表达进行了检测。对MMP－2及TIMP－2的表达与肝门胆管癌的组织分化程度、浸润转移及预后之间的关系进行分析。结果：MMP－2和TIMP－2表达阳性率分别为72％和76％。MMP－2的阳性表达率有淋巴结浸润的肝门胆管癌高于无淋巴结浸润的肝门胆管癌，低分化的肝门胆管癌高于高分化的肝门胆管癌。TIMP－2阳性表达率与以上相反。MMP－2表达与肝门胆管癌术后生存期呈负相关（γ=-0.713,P＜0．01），TIMP－2表达与肝门胆管癌术后生存期呈正相关（γ=0.652,P＜0．01）。MMP－2与TIMP－2具有负相关关系，（γ=-0.708,P＜0．01）。结论：MMP－2与TIMP－2是反映肝门胆管癌浸润、转移及预后的指标。     

Angiotensin-converting enzyme (ACE) inhibitor therapy after myocardial infarction in relation to left ventricular function

OBJECTIVE: To investigate to what extent and by what methods clinicians assess left ventricular (LV) function after an acute myocardial infarction (AMI) and how the results of the assessments relate to the use of angiotensin-converting enzyme (ACE) inhibitors; furthermore, to explore which main indications caused the clinicians to initiate ACE inhibitor therapy. DESIGN: From 16 hospitals we drew a sample of patients who were discharged with the diagnosis of AMI during a 3-month period in 1999/2000. Physicians in each hospital obtained the observed rate of use of cardiovascular drugs at discharge and also information on ejection fraction (EF) measurements. The results of the EF recordings were classified into three categories: >0.50, 0.40-0.50 and <0.40. The clinicians' main indications for drug use were reported. RESULTS: Among 767 patients discharged alive, EF was measured in 409 (53%), by echocardiography in 53% and by radionuclide ventriculography in 47%. Of the 409 patients 227 (55%) had EF >0.50, 95 (24%) EF 0.40-0.50 and 87 (21%) EF <0.40. Adjusted odds ratio for ACE inhibitor therapy being initiated during the AMI was 13.5 for those with EF <0.40 compared with those with EF >0.50. The main indication for starting ACE inhibitor therapy was heart failure (50%) followed by secondary prevention (42%). CONCLUSION: Measuring EF appears to be an important tool in the evaluation of AMI patients prior to discharge from hospital. Initiation of ACE inhibitor therapy related strongly to the results of the assessments.     

Connective tissue growth factor increases matrix metalloproteinase-2 and suppresses tissue inhibitor of matrix metalloproteinase-2 production by cultured renal interstitial fibroblasts

The involvement of gelatinase (matrix metalloproteinase-2 [MMP-2] and MMP-9) in the matrix remodeling and development of tubulointerstitial fibrosis has been studied recently, but relatively little is known about the regulators and the mechanisms controlling the activation and expression of gelatinase in renal fibroblasts. In these studies, the production and underlying signaling pathway for gelatinase by exogenous connective tissue growth factor (CTGF) treatment were investigated. Here, we show that CTGF acts as a potent promoter of the activation and expression of MMP-2, but not MMP-9 in normal rat kidney fibroblasts cell line (NRK-49F). We found that CTGF significantly increased the activity of MMP-2, as well as MMP-2 protein in conditioned medium and MMP-2 mRNA levels in cells. In studies to address the mechanisms involved in the regulation of MMP-2 activity, we found that the tissue inhibitor of matrix metalloproteinase-2 (TIMP-2), the inhibitor of MMP-2, decreased significantly when cells were treated with CTGF. Further studies showed that extracellular signal-regulated kinase (ERK) signaling is responsible for most of the CTGF-induced MMP-2 expression and TIMP-2 suppression. When NRK-49F fibroblasts were incubated with CTGF, activation of ERK1/2 signaling was observed. Suppression of ERK1/2 activation with nontoxic concentrations of PD98059, a specific inhibitor of ERK activation, was associated with a reduction of CTGF-stimulated MMP-2 activity and protein expression. In addition, the CTGF-mediated reduction of TIMP-2 activity and protein expression was prevented when ERK1/2 activation was inhibited by PD98059. These results provide evidence that CTGF augments activation of MMP-2 through an effect on MMP-2 protein expression and TIMP-2 suppression, and that these effects are dependent on the activation of the ERK1/2 pathway.     

膀胱癌中MMP-2、TIMP-2的表达及其与浅表性肿瘤复发的关系

目的：研究基质金属蛋白酶－2（MMP－2）和金属蛋白酶组织抑制因子－2（TIMP－2）在膀胱癌中的表达以及它们与肿瘤临床病理因素和复发的关系。方法：用免疫组织化学SP法检测46例膀胱移行细胞癌标本中MMP－2、TIMP－2的表达，并将它们与肿瘤临床和病理参数相比较。结果：在46例膀胱癌中，MMP－2、TIMP－2的阳性率分别为47.8%和58.7%，TIMP－2在间质中的表达率为47.8%。MMP－2表达率随着肿瘤理分级、临床分期的升高而增加，而TIMP－2表达率则呈下降趋势，但在浅表性膀胱癌（Ta-T1）中，TIMP－2的表达与MMP－2相似，随着肿瘤分期分级的升高而增加，TIMP－2间质表达阳性组中浅表性膀胱癌的2年复发率显著高于表达阴性组。结论：MMP－2和TIMP－2的相互作用对于膀胱癌的侵袭发展发挥了重要作用。TIMP－2在间质中表达可作为判断浅表性膀胱癌复发的预后指标。     

基质金属蛋白酶－9、细胞金属蛋白酶抑制因子－1在胃癌中的表达

目的：探讨基质金属蛋白酶－9（MMP－9）,组织金属蛋白酶抑制因子－1（TIMP－1）在胃癌中表达的意义。方法：采用免疫组化S－P法对47例胃癌组织进行MMP－9及TIMP－1的检测。结果：MMP－9,TIMP－1主要表达于癌周基质细胞,癌细胞少量表达,MMP－9,TIMP－1表达与胃癌患淋巴结转移（P＜0．01）,浆膜浸润相关（P＜0．01）;TIMP－1的表达与胃癌TNM分期相关（P＜0．05）,而MMP－9的表达与胃癌TNM分期无相关性（P＞0．05）。结论：MMP－9及TIMP－1可作为判断胃癌恶性行为的重要生物学标记物。     

Inhibition of apoptosis in rat mesangial cells by tissue inhibitor of metalloproteinase-1

BACKGROUND: Tissue inhibitor of metalloproteinase-1 (TIMP-1) is an important inhibitor of extracellular matrix degradation. Recently, it was reported that TIMP-1 also could inhibit apoptosis in B type lymphocyte. This study was designed to examine the effects of TIMP-1 on mesangial cell apoptosis. METHODS: The full-length cDNA of TIMP-1 was cloned and used to construct two recombinant vectors, TIMP-1S and TIMP-1AS, encoding sense TIMP-1 and antisense TIMP-1, respectively. The vectors were transfected into rat mesangial cells (RMC) and their expressions detected by Northern and Western blotting. Apoptosis was induced by serum deprivation, and was monitored for DNA fragmentation by TUNEL assay and DNA laddering. In addition, the expression of endogenous TIMP-1, matrix metalloprotein-2 (MMP-2), and MMP-9, as well as apoptosis-related genes Bcl-2 and Bax were investigated. RESULTS: TIMP-1AS transfection induced a suppression of TIMP-1 expression accompanied by an earlier onset of apoptosis, and TIMP-1S transfection induced TIMP-1 over-expression accompanied by a much later onset of apoptosis. A neutralizing antibody of TIMP-1 restored the sensitivity of TIMP-1S-transfected RMC to serum deprivation, but a synthetic matrix metalloproteinase inhibitor BB-94 did not influence the sensitivity of TIMP-1S-transfected RMC to serum deprivation. Finally, TIMP-1 over-expression inhibited the expression of Bax but with no effect on the expression of Bcl-2. CONCLUSION: TIMP-1 inhibits the serum deprivation-induced apoptosis in RMC, in which Bax might be involved.