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991.

Objectives

The purpose of our study is to verify, whether percutaneous mitral annuloplasty results in reverse remodeling in patients with functional mitral regurgitation (FMR) and impaired ejection fraction (EF) and to investigate which echo parameters may help in prediction of the efficacy of the procedure.

Background

FMR exacerbates left ventricular (LV) dilatation and contributes to both LV remodeling and heart failure.

Methods

We analyzed baseline and 1 month follow‐up data in 22 consecutive patients with FMR, who underwent successful percutaneous trans‐coronary venous mitral annuloplasty with the Carillon device.

Results

Significant reduction of FMR echo parameters, including vena contracta (VC), effective regurgitant orifice area (EROA), and regurgitant volume (RV) were observed and maintained throughout 1 month follow up and did not correlate with baseline annular, LV or with the left atrial diameters. Baseline mitral tenting area correlated negatively with the relative improvement (% difference) of EROA (r = ?0.5898) and RV (r = ?0.4363), but not with VC (r = 0.1341). In addition, increased EF as well as a significant reduction in left ventricular diameters were noted. The increase in EF negatively correlated with the change in EROA (r = ?0.50058), PISA (r = ?0.5327), and RV (r = ?0.5457). Baseline mitral tenting area significantly correlated with the 1 month change in EF (r = 0.5946) and stroke volume (r = 0.6913).

Conclusions

The improvement of FMR after treatment with the Carillon device is associated with LV reverse remodeling and an increase in systolic performance, that correlates with the reduction in mitral regurgitation, being not dependent on baseline heart diameters. Mitral tenting area seems to be an important parameter in prediction of benefit from percutaneous mitral annuloplasty.
  相似文献   
992.
BACKGROUND: In previous studies (the RITZ project), tezosentan, an intravenous (i.v.)-balanced dual endothelin (ET-A/B) antagonist, in doses of 50 and 100 mg/h, improved the hemodynamics but not the clinical outcome of patients with acute heart failure (AHF). OBJECTIVE: To evaluate the effect of lower doses of tezosentan in patients with AHF. SUBJECTS AND METHODS: Included were 130 patients hospitalized due to AHF with dyspnea at rest, despite initial treatment, and were in need of hemodynamic monitoring with cardiac index (CI)<2.5 l/min/m(2) and wedge pressure > or = 20 mm Hg. Patients were randomized in a double-blind fashion to receive placebo or tezosentan: 0.2, 1, 5, or 25 mg/h for 24 h. RESULTS: The primary endpoint of the study, CI increase at 6 h of treatment, was significant in the 5 and 25 mg/h groups. Tezosentan induced a dose-dependent increase in CI and a decrease in wedge pressure, peaking after 3 h in the 5 and 25 mg/h groups. In the 1 mg/h group, this effect was smaller during the first 6 h and increased gradually, becoming significant at 24 h and beyond treatment discontinuation. There was no hemodynamic effect in the 0.2 mg/h arm. Type-B natriuretic peptide (BNP) decreased in the 1, 5, and 25 mg/h groups but not on placebo. Endothelin levels were significantly increased by the 5 and 25 mg/h groups but not in the lower (< or = 1 mg/h) tezosentan doses. Urine output decreased on the 25 mg/h dose. There was a trend towards improvement in patients' subjective dyspnea score and worsening heart failure events, mainly in the 1 mg/h group. CONCLUSIONS: In patients admitted with AHF, tezosentan doses of 1-25 mg/h are efficacious in improving the hemodynamics and reducing BNP. Tezosentan doses beyond 1 mg/h increased plasma endothelin levels and reduced urine output, probably limiting their clinical efficacy, as compared to tezosentan 1 mg/h.  相似文献   
993.
Congenital hepatic fibrosis belongs to the fibrocystic diseases of the liver and represents ductal plate malformation of interlobular bile ducts, along with a destructive cholangiopathy associated with fibrosis. Four patients with congenital hepatic fibrosis are described. Their median age at presentation was 25 years; none of them had a family history of liver or renal disease. Variceal bleeding was the initial manifestation in three patients. All of them required frequent endoscopic variceal ligation sessions and distal splenorenal shunting was also performed in two, almost obviating the need for further variceal ligation. Variceal bleeding did not recur during follow-up. One of these three patients rarely exhibited acute cholangitis; administration of ursodeoxycholic acid resulted in complete remission. In contrast, the fourth patient showed frequent severe episodes of acute cholangitis but normal cholangiographic findings. He underwent liver transplantation but died 2 months later. Laboratory findings disclosed pancytopenia in all patients whereas hepatic synthetic capacity was well preserved. Renal function was unaffected despite the presence of polycystic kidneys in two patients. In summary, congenital hepatic fibrosis can also be diagnosed in older ages, might have strikingly different manifestations and is associated with prominent portal hypertension necessitating aggressive management in order to prevent variceal bleeding.  相似文献   
994.
Background Treatment options for patients with ventricular arrhythmias have undergone major changes in the last 2 decades. Trends in use of invasive procedures, clinical outcomes, and expenditures have not been well documented. Methods We used administrative databases of Medicare beneficiaries from 1985 to 1995 to identify patients hospitalized with ventricular arrhythmias. We created a longitudinal patient profile by linking the index admission with all earlier and subsequent admissions and with death records. Results Approximately 85,000 patients aged ≥65 years went to hospitals in the United States with ventricular arrhythmias each year, and about 20,000 lived to admission. From 1987 to 1995, the use of electrophysiology studies and implantable cardioverter defibrillators in patients who were hospitalized grew substantially, from 3% to 22% and from 1% to 13%, respectively. Hospital expenditures rose 8% per year, primarily because of the increased use of invasive procedures. Survival improved, particularly in the medium term, with 1-year survival rates increasing between 1987 and 1994 from 52.9% to 58.3%, or half a percentage point each year. Conclusion Survival of patients who sustain a ventricular arrhythmia is poor, but improving. For patients who are admitted, more intensive treatment has been accompanied by increased hospital expenditures. (Am Heart J 2002;144:413-21.)  相似文献   
995.
Effects of melatonin on proliferation of cancer cell lines   总被引:1,自引:0,他引:1  
Papazisis KT, Kouretas D, Geromichalos GD, Sivridis E, Tsekreli OK, Dimitriadis KA, Kortsaris A.H. Effects of melatonin on proliferation of cancer cell lines. J. Pineal Res. 1998; 25:211–218. © Munksgaard, Copenhagen The pineal hormone melatonin has been reported to have in vitro antiproliferative effects on estrogen receptor-positive human breast cancer cell lines at concentrations near to plasma physiological concentrations (1 times 10-11 to 1 times 10-9 M). Its growth inhibitory actions have been thought to be linked to the estrogen-receptor system. We tested the cytotoxic effects of melatonin on MCF-7 and T47D human breast cancer cell lines by using the SRB (sulforhodamine-B), XTT-tetrazolium, and bromodeoxyuridine (BrdU) assays in 96-well microtiter plates. After a 3 or 4 day exposure, melatonin did not have any significant effect on breast cancer cell proliferation and survival in doses up to 1 times 10-4 M. Doses higher than 1 mM exhibited a potent cytotoxic effect, which was not mediated by the estrogen-receptor or by protein tyrosine kinases and was not specific for breast cancer cell lines. Intracellular glutathione levels did not seem to play any role in the sensitivity of breast cancer cells to melatonin, since the addition of L-buthionine-[S,R]-sulfoximine, ethacrynic acid, or exogenous glutathione did not modify our results. We conclude that under our experimental conditions melatonin has no inhibitory effects on human breast cancer cells at low (physiological or supraphysiological) concentrations. The different experimental procedures that were utilized in the present study can partially explain the divergence between our results and the literature.  相似文献   
996.
The aim of the study was to prove the long-lasting and continuously harmful effect of chronic Chlamydia pneumoniae (CPn) infection on vessel walls in patients with diffuse coronary artery disease (CAD). In surgically obtained endarterectomized atherosclerotic plaques grade VI-VIII (Stary classification) from 10 patients with diffuse coronary artery disease and chronic (7) or past (3) CPn infection, signs of inflammatory response of the vessel wall on infectious agents were studied. In all 10 endarterectomized plaque step serial sections, immunologic signs of vessel wall response were present (positive T- and B-lymphocytes, macrophages, and capillarogenesis). In 8 of 10 patients' atherosclerotic plaque, unique features of active vasculitis in the neoarteriolar wall as well as arteriologenesis, were found. Seven of these 8 patients had serologically proven chronic CPn infection, and 1 had past infection. Features of vasculitis as well as arteriologenesis were absent in 2 patients who recovered from CPn infection at the time of surgery. In the endarterectomized segments of 3 randomly chosen patients in this study, the polymerase chain reaction method revealed positive DNA of CPn. Two of these patients had chronic infection, but the third had only a past CPn infection. This study provides evidence that CPn infection has continuous and a long-lasting inflammatory response in the high-grade atherosclerotic coronary artery vessel wall.  相似文献   
997.
In view of obscure clinical and biological significance of leukemic cells heterogeneity, we studied the efficacy of apoptosis, proliferation, and expression levels of the Bcl-2, MDR1, LRP, and BCRP genes in sorted CD34+ and CD34− subpopulations of childhood AML leukemic samples. In five out of nine cases, CD34+ cells were less sensitive to spontaneous apoptosis and had from 1.2- to 5.0-fold higher expression levels of Bcl-2 (eight of ten) and from 1.5- to 28.7-fold higher expression levels of MDR1 (eight of ten). The expression levels of the LRP gene were from 1.1- to 1.8-fold higher in CD34+ subpopulations (five of ten cases), and the expression levels of the BCRP gene were from 1.1- to 22.4-fold higher in CD34+ leukemic cells (six of ten). In all M4 cases, the expression levels of LRP were higher in the CD34− subpopulation. Significant differences in the patterns of genes expression between patients do not allow us to conclude that the CD34+ fractions have more resistant phenotype than the CD34− subpopulations. Nevertheless, distinctions between CD34+ and CD34− cells may lead to different chemosensitivities between leukemic subpopulations in vivo and may determine the alteration of the leukemic immunophenotype during treatment and in relapse.  相似文献   
998.
Objectives

To investigate the effect of a zinc oxide/zinc sulphate-based cement as a temporary filling material during root canal treatment on the occurrence of cracks within the filling material or the tooth.

Materials and methods

Root canals of 122 extracted human molars were prepared using ProTaper instruments. Standardized occlusal-distal cavities were prepared. After placing calcium hydroxide into the root canals, the teeth were divided randomly into four groups containing 33 specimens each. In the Coltosol group, the cavity was completely filled with Coltosol® F. In the Coltosol-Clearfil group, a 2-mm layer of Coltosol® F was placed into the apical part of the pulp chamber, and in the Clearfil group, a foam pellet was placed into the coronal pulp chamber. The remaining cavities were filled with Clearfil™. In the control group, the cavities were not restored. The teeth were stored at 37 °C for 14 days and examined every 24 h under a stereomicroscope.

Results

Fractures of the filling and/or the tooth were only observed in the Coltosol group. All Coltosol® F restorations had cracks after 24 h. Tooth fractures were found in 25 (76 %) teeth. Among these teeth, 21 (84 %) had crown fractures, four (16 %) had root-crown fractures. All root-crown fractures were vertical.

Conclusion

Coltosol® F when used alone led to tooth fractures in two-surface class II cavities in teeth undergoing root canal treatment.

Clinical relevance

Coltosol® F solely used as restorative material may lead to tooth fractures in two-surface class II cavities.

  相似文献   
999.
Objective: To evaluate the extent to which different types of malocclusion influence the development of affective/romantic relationships among young adults of both sexes.Materials and Methods: A cross-sectional study was conducted with 360 men and women ranging in age from 18 years to 25 years. Criteria for exclusion from the sample were the following: participants could not be married, visually impaired, or students of a higher education course in the area of health. In this study, images of young adult men and women in the same age range as that of the evaluators were used. These images were manipulated to create different types of malocclusion: diastema, open bite, crowding, gingival (or gummy) smile, little exposure of teeth. Six groups of images containing six images each were formed and consisted of two experimental images (digitally manipulated) and four control images. These images were provided to the participants, who evaluated them by means of a questionnaire and a visual analog scale. The Kruskal-Wallis, Mann-Whitney, chi-square, and Fisher exact tests were used for data analysis.Results: All malocclusions had a negative impact on acceptance by the evaluators for the purposes of affective/romantic relationships, with crowding being the type of malocclusion that led to the highest level of rejection (P < .01).Conclusion: Malocclusions have a negative influence on the development of affective/romantic relationships among young adults. Individuals with good occlusion are seen in a more positive light, from the perspective of affective life.  相似文献   
1000.
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