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目的:分析卵巢癌组织中白细胞介素18(IL-18)及白细胞介素1β转化酶(ICE)的基因及蛋白表达水平,探讨其与卵巢癌临床特性之间的关系.方法:分别采用RT-PCR及免疫组化染色法检测正常卵巢(n=10)、卵巢良性肿瘤(n=6)、卵巢癌(n=32)组织中IL-18、ICE的mRNA及蛋白表达;分析卵巢癌不同病理类型、临床分期及发病年龄患者之间表达是否具有差异.结果:①正常、良性肿瘤及卵巢癌组织中均有IL-18 mRNA表达(分别为1.30±0.48、1.02±0.17、0.77±0.35);ICE mRNA在正常及良性肿瘤组织中均有表达,卵巢癌组织中有29例(90.63%)表达(分别为0.96±0.51、0.73±0.34、0.63±0.34).②IL-18及ICE蛋白均表达于卵巢上皮细胞浆内.正常、良性肿瘤及卵巢癌组织的IL-18阳性表达率分别为83.3%、80.0%和31.3%;ICE阳性表达率分别为80.0%、50.0%和37.5%.③卵巢癌组织中IL-18、ICE mRNA及蛋白表达均较正常及良性肿瘤组织明显减少(均P<0.05),良性与正常组织之间相比差异均无显著性(均P>0.05).卵巢癌组织中IL-18与ICE的mRNA、蛋白表达之间呈显著正相关(分别为r=0.37,P=0.036;r=0.45,P=0.009).④IL-18、ICE mRNA及蛋白表达在不同病理类型、临床分期及发病年龄患者之间均未见显著性差异(均P>0.05).结论:卵巢癌患者局部癌组织IL-18、ICE表达减弱,可能与卵巢癌的发生发展有着一定的关系.  相似文献   
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BACKGROUND: In order to clarify the relationship between chromosomal rearrangements, sperm morphology and interchromosomal effects (ICE), we studied the spermatogenetic defects in seven infertile Robertsonian translocation carriers. METHODS: Lymphocyte karyotypes were evaluated using Giemsa-Trypsin-Giemsa banding and fluorescence in-situ hybridization (FISH). Semen analysis was performed by light and transmission electron microscopy. FISH of sperm nuclei was carried out to detect possible ICE. RESULTS: Lymphocyte karyotype analysis revealed five t(13;14), one t(13;21) and one t(14;22) carriers. Sperm ultrastructural examination highlighted a higher percentage of immaturity, apoptosis and necrosis than in controls. Aneuploidies of gonosomes were detected in sperm from five out of six carriers of Robertsonian translocation, whereas aneuploidy of chromosome 18 was evident in three out of six carriers. The frequencies of diploidy were altered in all cases. CONCLUSIONS: Since these infertile patients showed severe spermatogenetic impairment from the morphological and meiotic points of view, we recommend detailed sperm ultrastructural and chromosomal analysis before undertaking ICSI cycles in Robertsonian translocation carriers.  相似文献   
4.
The reaction of nitric oxide (NO) and superoxide results in the formation of peroxynitrite, a potent and relatively long-lived oxidant. In infectious diseases, these molecules are not only bactericidal but also toxic to host cells. Chorioamnionitis is often complicated by premature rupture of membranes and can be associated with placental abruption. These diseases are significant causes of premature low-birth-weight deliveries and consequently the morbidity and mortality of neonates. Lipopolysaccharide, bacterial endotoxin, is known to be elevated in the amniotic fluid of patients with chorioamnionitis. Lipopolysaccharide is known to induce the formation of NO and superoxide. We report here that nitrite/nitrate, stable metabolites of NO, were increased in serum from patients with chorioamnionitis. Immunohistochemical studies demonstrated enhanced expression of inducible NO synthase and formation of nitrotyrosine, a footprint of peroxynitrite, in the placentae from patients with chorioamnionitis and also in patients with placental abruption. Furthermore, apoptotic cell death was also increased in the placentae from patients with both diseases. These results suggest that chorioamnionitis and a portion of placental abruption may share a common cascade of placental injury. Nitric oxide and its metabolities may play an important role in this cascade.  相似文献   
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This work was aimed at the study of the viscoelastic properties of two current light-cured dental resin composites, Rok (hybrid) and Ice (nanohybrid), by dynamic mechanical analysis, under the influence of variable temperatures and frequencies 1 h after curing or after storage at 37°C either in air or distilled water for 1, 7 or 30 days. They both contain about the same amount of filler, which is strontium aluminosilicate particles, but they have different size distribution, 40 nm–2.5 μm for Rok and 10 nm–1 μm for Ice. The resin matrix of Rok consists of UDMA, while that of Ice consists of UDMA, Bis-EMA and TEGDMA. During dynamic testing elastic modulus (E′), viscous modulus (E″) and loss tangent (tan δ) were determined over a temperature range from 25 to 185°C at a frequency of 0.1, 1.0 or 10.0 Hz. The elastic modulus (8.40 ± 0.61 GPa) and tan δ (0.114) of Rok at 37°C and 1 Hz was slightly higher than that of Ice (E′ = 7.58 ± 0.50 GPa and tan δ = 0.110) which, however, were not statistically different (P ≤ 0.05). Both the light-cured composites showed two T g values, at 58 and 121°C for Rok and at 63 and 117.0°C for Ice. The first T g has an apparent value, since inside the glass transition region an additional curing reaction occurred of the unreacted C=C methacrylate groups; the second T g is due to the new material formed during the DMA scan. During the storage of composites in air or water also an additional curing reaction took place. The nanohybrid Ice showed a slight lower elastic modulus and tan δ than the hybrid Rok at 25–50°C, which, however, were not statistically different (P ≤ 0.05).  相似文献   
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ObjectivesThis dual-center study sought to demonstrate the utility and safety of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to transesophageal echocardiography (TEE) during Amplatzer Cardiac Plug device implantation.BackgroundOver 90% of intracardiac thrombi in atrial fibrillation originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA percutaneous occlusion. TEE is typically used to guide implantation.MethodsICE-guided percutaneous LAA closure was performed in 121 patients to evaluate the following tasks typically achieved by TEE: assessment of the LAA dimension for device sizing; guidance of transseptal puncture; verification of the delivery sheath position; confirmation of location and stability of the device before and after release and continuous monitoring to detect procedural complications. In 51 consecutive patients, we compared the measurements obtained by ICE and fluoroscopy to choose the size of the device.ResultsThe device was successfully implanted in 117 patients, yielding a technical success rate of 96.7%. Procedural success was achieved in 113 cases (93.4%). Four major adverse events (3 cardiac tamponades and 1 in-hospital transient ischemic attack) occurred. There was significant correlation in the measurements for device sizing assessed by angiography and ICE (r = 0.94, p < 0.0001).ConclusionsICE imaging was able to perform the tasks typically provided by TEE during implantation of the Amplatzer Cardiac Plug device for LAA occlusion. Therefore, we provide evidence that the use of ICE offered accurate measurements of LAA dimension in order to select the correct device sizes.  相似文献   
9.

Objectives

This study sought to evaluate the feasibility, safety, and efficacy of intracardiac echocardiography (ICE)–guided versus transesophageal echocardiography (TEE)–guided left atrial appendage occlusion (LAAO) by the use of Amplatzer Cardiac Plug or Amulet devices included in a large Italian registry.

Background

TEE is widely used for LAAO procedure guidance. ICE may be a potential alternative imaging modality in LAAO.

Methods

Data from 604 LAAO procedures performed in 16 Italian centers were reviewed. ICE-guided LAAO was performed in 187 patients, whereas TEE was used in 417 patients. Procedural success was defined as LAAO without occurrence of pericardial tamponade, stroke, systemic embolism with end organ damage, major bleeding, and device embolization. Stroke, transient ischemic attack, major bleeding, overall and cardiovascular death were analyzed.

Results

CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65 to 74 years, sex category) and HAS-BLED (hypertension, abnormal renal and liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol) scores were similar between the ICE and TEE groups. TEE implied lower procedural (delta 12 min) and fluoroscopy time (delta 5 min) when compared with ICE. Procedural success was similarly high (≥94%) between the TEE and ICE groups with a complication rate of 6.5% for TEE versus 4.2% for ICE (odds ratio: 1.468; 95% confidence interval: 0.681 to 3.166; p = 0.327). At median follow-up of 451 days (interquartile range: 162 to 899 days), the rate of cerebral ischemic events was similar between TEE-guided and ICE-guided procedures.

Conclusions

ICE-guided LAAO by means of Amplatzer devices may represent a second alternative imaging modality after an appropriate learning curve and bearing in mind that pre-procedural computed tomography imaging is mandatory. When comparing ICE with TEE, TEE remains the gold standard.  相似文献   
10.
Interleukin-1beta converting enzyme (caspase-1) in intestinal inflammation   总被引:6,自引:0,他引:6  
An imbalance of T helper cell type 1 (Th1) versus type 2 (Th2) polarization in favor of Th1 cell subsets appears to be a key pathogenic mechanism in chronic inflammatory bowel disease (IBD), in particular in Crohn's disease. The interferon gamma-inducing factor interleukin (IL)-18 acts in strong synergism with the Th1 polarizing cytokine IL-12. Recent studies provide evidence for the participation of IL-18 in the pathogenesis of IBD: IL-18 expression is increased in inflamed lesions of Crohn's disease patients and neutralization of IL-18 in different models of experimental colitis resulted in a dramatic amelioration of disease severity. IL-18 and IL-1beta are cleaved and thereby activated by the interleukin-1beta converting enzyme (ICE). Activation of ICE also occurs during different types of infectious colitis, and ICE expression and subsequent release of IL-1beta and IL-18 significantly contribute to intestinal inflammation. ICE knockout mice as well as mice treated with the ICE inhibitor pralnacasan are protected against experimental mucosal inflammation. Thus, inhibition of ICE represents an intriguing new target that requires further investigation in animal models.  相似文献   
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