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991.
Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play an important role in several diseases. This study was undertaken to investigate the mRNA synthesis of MMP2, MMP9, membrane-type 1 (MT1)-MMP, and matrix metalloproteinase inhibitors TIMP1 and TIMP2 by in situ hybridization in a set of heart mitral and aortic valves operatively removed due to degenerative or inflammatory valvular diseases. The material consisted of 21 valves, eight with endocarditis and 13 with a degenerative valvular disease. The samples were studied by in situ hybridization with specific probes for MMP2, MMP9, MT1-MMP, TIMP1, and TIMP2. Synthesis of MMP2 mRNA was found in seven valves, five with endocarditis and two with degenerative valvular disease. Signals for MMP9 mRNA were found in two cases with endocarditis and five cases with degenerative valvular disease. No signal for MT1-MMP mRNA was found in the lesions. TIMP1 mRNA, on the other hand, was found in 17 cases, both endocarditis and degenerative valvular disease. TIMP2 mRNA was found in three cases of endocarditis. The signals for MMP2, MMP9, TIMP1, and TIMP2 mRNA were localized in endothelial cells and in fibroblast-like cells expressing alpha-smooth muscle actin, thus showing myofibroblast-type differentiation. The results show that matrix metalloproteinases MMP2 and MMP9, and matrix metalloproteinase inhibitors TIMP1 and TIMP2 mRNAs are synthesized in diseased valves and suggest that they may contribute to matrix remodelling in valvular disease. 相似文献
992.
W. D. Ratnoff M. A. Matthay M. Y. S. Wong Y. Ito K. H. Vu J. Wiener-Kronish E. J. Goetzl 《Journal of clinical immunology》1988,8(4):250-258
The human pulmonary edema fluid concentrations of LTC4 and of LTD4 and LTE4, derived peptidolytically from LTC4, were assessed by radioimmunoassays of the mediators resolved by reverse-phase high-performance liquid chromatography. The mean pulmonary edema fluid concentration (± SD) of LTD4 of 19.2±25.6 nM for 12 patients with the adult respiratory distress syndrome and of LTE4 of 192±309 nM for 10 of the patients were significantly higher (P<0.005 andP<0.05) than those of 2.2±2.4 and 11.0±18.2 nM, respectively, for 10 patients with cardiogenic pulmonary edema, whereas the lower mean concentrations of LTC4 were not significantly different for the two groups. Pulmonary edema fluid from five patients with adult respiratory distress syndrome, one with cardiogenic pulmonary edema, and one with an indeterminate syndrome contained similar concentrations of peptidoleukotriene peptidases. The LTC4 and LTD4 peptidolytic activities in ARDS fluids were 81 and 142 kD, respectively, by gel filtration. The extents of peptidolysis of [3]LTC4 and [3]LTD4 by 100 µl of pulmonary edema fluid attained respective mean maximum levels of 74.5±2.9% (N=5) and 37.7±10.2% (N=4) after 30 min at 37°C and were inhibited by serine-borate and by cysteine, respectively. The predominance of LTD4 and LTE4 over LTC4 in states of altered pulmonary vascular pressure and permeability thus is attributable to two distinct peptidases. 相似文献
993.
将辣根过氧化物酶(HRP)结晶涂于大鼠右侧迷走神经心支近侧断端,在同侧迷走神经背侧运动核、疑核以及两核之间的网状结构内发现标记细胞。根据实验结果,对心脏迷走神经节前纤维的起源进行了讨论。 相似文献
994.
Bae SH Yoon SK Jang JW Kim CW Nam SW Choi JY Kim BS Park YM Suzuki S Sugauchi F Mizokami M 《Journal of Korean medical science》2005,20(5):816-820
Hepatitis B virus (HBV) is one of the major causative agents of chronic liver diseases in Korea. HBV has been classified into 8 genotypes by a divergence of >8% in the entire genomic sequence, and have distinct geographic distributions. There are limited data on the relevance between HBV genotypes and clinical outcomes in Korea. To investigate the clinical feature relating to HBV genotype in Korea, a total 120 serum samples with HBsAg (65 from Seoul and 55 from the other city in Korea) were obtained from each 30 chronic HBV carriers with asymptomatic carrier (ASC), chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). HBV genotype was determined by either enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies against genotype-specific epitopes in the preS2-region or the direct sequencing of small S gene. HBV genotypes were determined in 105 (87.5%) of 120 samples. HBV genotype C was identified in all HBV carriers with ASC, CH, LC, and HCC. Genotypes A, B, D, E, F and G were not detected in any of them. Genotype C HBV prevails predominantly among chronic carriers of the virus in Korea, irrespective of their clinical stages of liver disease and geographic origin. 相似文献
995.
目的:探讨阿霉素(Adr)对心和肾损伤与一氧化氮合酶(NOS)表达。方法:用治疗剂量阿霉素静脉注射法建立兔心、肾损伤模型组,测定兔心输出量(CO)、左心室收缩压(LVSP)、左心室舒张末压(LVEDP):取心和肾组织进行HE染色及超薄切片染色;NADPH组化染色并进行图像分析,观察动物心和肾组织中ALP、Ca~(2+)-ATP酶和 NOS的变化。结果:实验组CO、LVSP均明显低于对照组,LVEDP明显高于对照组;实验组心和肾组织的超微结构受损伤,Ca~(2+)-ATP酶活性明显下降,而NOS表达明显上调。结论:治疗剂量阿霉素能够降低心和肾组织中Ca~(2+)-ATP酶的活性和上调NOS的表达,是导致心和肾组织损伤的重要原因。 相似文献
996.
Summary We describe a purification method for tissue culture-grade trypsin that yields an enzyme mixture with reproducible activities of trypsin, elastase, and chymotrypsin and eliminates amylase and lipase. 相似文献
997.
Pizzuti A Sarkozy A Newton AL Conti E Flex E Digilio MC Amati F Gianni D Tandoi C Marino B Crossley M Dallapiccola B 《Human mutation》2003,22(5):372-377
Two out of 47 patients with sporadic tetralogy of Fallot (TOF), the most common cyanotic conotruncal heart defect (CTD), showed heterozygous missense mutations of the ZFPM2/FOG2 gene. Knockout mice carrying mutations in the ZFPM2/FOG2 gene have similarly been found to exhibit TOF. While both mutant ZFPM2/FOG2 proteins, E30G (c.88A>G) and S657G (c.1968A>G), retain the ability to bind the partner protein GATA4 and repress GATA4 mediated gene activation, the S657G, but not the E30G, mutation is subtly impaired in this function. ZFPM2/FOG2 gene mutations may contribute to some sporadic cases of TOF. 相似文献
998.
Analysis of gene expression patterns in small amounts of human ventricular myocardium by a multiplex RNase protection assay 总被引:3,自引:0,他引:3
C. Mittmann Ursula Münstermann Joachim Weil Michael Böhm Stefan Herzig Christoph Nienaber Thomas Eschenhagen 《Journal of molecular medicine (Berlin, Germany)》1998,76(2):133-140
End-stage human heart failure is associated with changes in expression of steady-state messenger RNA (mRNA) levels. These
changes correspond to alterations in protein levels and myocardial function and may have clinical implications regarding etiology,
clinical state, or prognosis. However, analysis of mRNA levels in endomyocardial biopsies can be accomplished only by the
quantitative polymerase chain reaction, which is difficult to standardize. The aim of the study was to evaluate whether the
RNase protection assay is applicable to measure mRNAs of multiple genes simultaneously in small amounts of ventricular myocardium
comparable to myocardial biopsies. Total RNA was prepared from left ventricular myocardium from terminally failing hearts
with idiopathic (n=9) or ischemic cardiomyopathy (n=7) and from nonfailing control hearts (n=10). mRNA was measured by an optimized RNase protection assay for the β1-adrenoceptor, the stimulatory G protein α-subunit (Gsα), phospholamban, the calcium ATPase of the sarcoplasmic reticulum (SERCA), β-myosin heavy chain (β-MHC), and the atrial natriuretic
peptide (ANP). We extracted 10.7±2.1 μg total RNA from three myocardial biopsies taken in vitro. All of the six genes were
measurable in duplicate in a total of 7 μg RNA. mRNAs of β1-adrenoceptor, phospholamban, and SERCA were lower in failing than in nonfailing myocardium by 50%, 33%, and 42% respectively,
whereas β-MHC and Gsα mRNAs were unchanged. mRNA of ANP was expressed at high levels only in the failing myocardium, providing a highly specific
and sensitive marker for discriminating nonfailing and failing hearts. A direct comparison with ANP and Gsα levels obtained by Northern blot analysis with 7.5 μg total RNA showed a good correlation between the two methods. The RNase
protection assay is thus a suitable method for simultaneous measurements of multiple mRNA levels in human myocardial biopsies.
Changes in mRNA levels closely reflected those identified by other methods using larger amounts of RNA. Increased myocardial
ANP mRNA levels determined by the RNase protection assay may serve as a molecular marker of heart failure.
Received: 12 May 1997 / Accepted: 8 September 1997 相似文献
999.
Jauniaux Eric; Gavrill Panagiotis; Khun Peter; Kurdi Wesam; Hyett Jon; Nicolaides Kypros H. 《Human reproduction (Oxford, England)》1996,11(2):435-439
Fetal heart rate, umbilical artery pulsatility index, end-diastolicflow,nuchal translucency thickness and placental thickness were recordedin 250 women with a viable singleton pregnancy undergoing chorionicvillous sampling for fetal karyotyping at 11–14 weeksof gestation. The fetal karyotype was normal in 210 cases andabnormal in 40, including 21 with trisomy 21, 13 with trisomy18, three with triploidy, two with monosomy X and one with trisomy13. A total of 52 fetuses with a normal karyotype had a nuchaltranslucency 3 mm and were considered separately. There wasa stable and significant increase in the mean fetal heart ratein trisomy 21 pregnancies compared to controls. No significantdifference was found for the other variables between the groups.In chromosomally normal fetuses with an increased nuchal thickness,the development of fetal heart rate and compliance of the umbilico-placentalcirculation were within the normal ranges. Some fetuses withtrisomy 18 or triploidy had an increased resistance to bloodflow in the umbilical artery, which was probably due to abnormalplacental development. 相似文献
1000.
Savchenkova AP Dudnik LB Pogoretskaya IL Solov'eva NP Pokrovskaya MA Aseichev AV Drinitsyna SV Azizova OA Lopukhin YM 《Bulletin of experimental biology and medicine》2003,135(1):29-33
In patients with coronary heart disease oxidizability of lipids during Cu2+-induced oxidation of blood plasma inversely correlated with fibrinogen content. A positive correlation was found between the amount of lipid peroxidation products in the plasma from these patients and fibrinogen content. The increase in fibrinogen content was associated with high levels of total lipids and triglycerides and low concentration of high-density lipoprotein cholesterol. In vitro experiments demonstrated that fibrinogen reduces oxidizability of blood plasma. Our results suggest that the decrease in lipid oxidizability at high concentration of fibrinogen in patients with coronary heart disease is related to predominant oxidation of fibrinogen and its competition with plasma lipids during Cu2+-induced oxidation. 相似文献