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941.
942.

Assessment of left ventricular filling pressure (LVFP) is crucial in patients with ST-segment elevation myocardial infarction (STEMI). Since current guideline recommended echocardiographic parameters have limited value, more comprehensive assessment methods are required in this patient subset.In this study, we aimed to investigate the clinical utility of left atrial reservoir strain (LARS) imaging in patients treated with primary percutaneous coronary intervention (pPCI). Patients who underwent successful pPCI were included. Left ventricular end-diastolic pressure (LVEDP) was measured invasively following pPCI. Left atrial strain imaging was performed following pPCI within 24 h of pPCI. Normal LARS value was accepted as above 23%. We prospectively enrolled 69 patients; there were 18 patients with LARS below 23% who were included into group 1 and rest of the study population included into group 2. There was no significant difference between groups in terms of comorbidities.Troponin and pro-BNP levels were significantly higher in group 1 (p: 0.036 and 0.047 respectively). Left atrial volume and tricuspid regurgitation velocity were similar between groups (p: 0.416 and p: 0.351 respectively). Septal tissue velocity was higher (p: 0.001) and Septal E/e’ ratio was lower (p: 0.004) in group 2. Left ventricular (LV) global longitudinal strain value was higher in group 1 which is consistent with observed lower ejection (LVEF) fraction in group 1 (p: 0.001 for LV strain and p: 0.001 for LVEF). Estimated mean LVFP was also higher in group 1 (p: 0.003).Correlation analyses revealed moderate correlation between LARS and LVEDP (r: ? 0.300). Our results indicate that left atrial strain imaging is a promising tool for the assessment of left atrial pressure in patients with STEMI.

  相似文献   
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Background

To treat viral infection of chronic hepatitis C (CHC) is a main strategy to prevent progression of liver disease, and cancer. Some patients with CHC have failed to respond to the common antiviral therapy in different populations.

Objectives

In the current study it was aimed to find out the possible role of multiple drug resistance gene1 (MDR1) in non-responder patients with CHC infection in Turkish population.

Patients and Methods

Peripheral blood-EDTA samples were used for total genomic DNA isolation. In total of 55 patients with chronic hepatitis C and positive results for genotype 1 [31 male (56.4%), 24 female (43.6%) and mean age-min-max; 56.9 ± 9.66 (39-71)]; 19 responder (34.5%), 21 non responder (38.2%), and 15 recurrence (27.3%) were included in the presented results. Functional MDR1 gene was genotyped by multiplex PCR-based reverse-hybridization Strip Assay method, and some samples were confirmed by direct sequencing.

Results

Our results indicate that MDR1 gene polymorphism is strongly associated with non-responder patients and those with recurrent chronic hepatitis C during conventional drug therapy when compared to the responder patients. Homozygous of the TT genotype for MDR1 exon 26 polymorphism was at 2.0-fold higher risk of non-responder than patients with CC and CT.

Conclusions

The homozygous MDR1 3435TT genotype which encodes the xenobiotic transporter P-glycoprotein may be associated with a poor antiviral response in HCV chronicity during conventional therapy, and large-scale studies are needed to validate this association.  相似文献   
947.
Introduction: The aim of this study is to assess circulating thrombopoietin concentrations in patients with both clonal and reactive thrombocytosis (RT), which are two distinct categories of extreme platelet production circumstances. Investigation of the thrombopoietin levels in clonal versus reactive thrombocytosis may help us to understand the interactions of this key regulatory cytokine and the conditions in which abnormally increased platelet formation exist.

Materials and methods: Thrombopoietin levels were measured in patients with platelet counts greater than 500 × 103 μl?1 The study population consisted of 21 patients with RT (13 with iron deficiency anemia, and 8 with rheumatoid arthritis), 24 patients with clonal thrombocytosis (six with essential thrombocytosis, three with myelofibrosis, eight with chronic myelogenous leukemia, and seven with polycythemia vera (PV)) and 16 healthy subjects were used as controls.

Results: The median plasma thrombopoietin concentration was 100.5 pg ml?1 in patients with RT, 467pg ml?1 in patients with clonal thrombocytosis and 62.65pgml?1 in the control group. The thrombopoietin concentration was found to be higher in the patients with primary thrombocytosis when compared to the control group (p = 0.001), as well as in patients with RT (p = 0.002). However, there was no statistically significant difference between the patients with RT and the control group (p = 0.14). There was no correlation between thrombopoietin levels and the platelet counts in patients with clonal thrombocytosis, including essential thrombo- cythemia (ET).

Conclusion: Increased levels of thrombopoietin were found in patients with clonal thrombocytosis versus patients with RT and control subjects as well. Defective clearance of thrombopoietin by megakaryocytes and platelets due to a reduced number of thrombopoietin receptors may be the causative mechanism behind this. These results indicate that plasma thrombopoietin levels may be helpful in distinguishing between clonal and reactive thrombocytosis.  相似文献   
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Background

Coronary flow reserve (CFR) provides independent prognostic information in diabetic patients with known or suspected coronary artery disease. However, there have been no substantial data to evaluate CFR in prediabetics. Accordingly, we aimed to evaluate CFR in subjects with prediabetes using second harmonic transthoracic Doppler echocardiography.

Methods and Results

We measured CFR of 65 subjects with prediabetes, 45 patients with overt type 2 diabetes, and 43 sex and age matched normoglycemic healthy subjects with normal glucose tolerance. Ages, gender, existence of hypertension or hypercholesterolemia, smoking status were similar among the groups. CFR was significantly lower in diabetics (2.15 ± 0.39) than in prediabetics (2.39 ± 0.45) and controls (2.75 ± 0.35); in addition, it was significantly lower in prediabetics than controls. Only 2 (5%) of control subjects had abnormal CFR (< 2) but 11 (17%) prediabetic subjects and 19 (42%) diabetic patients had abnormal CFR. We found that only age (β = − 0.31, P < 0.01) and presence of the diabetes (β = − 0.57, P < 0.01) were significant predictors of lower CFR in a multivariable model that adjusted for other variables. CFR was significantly and inversely correlated with age (r = − 0.15, P = 0.04), fasting glucose level (r = − 0.27, P = 0.001), postprandial glucose level (r = 0.43, P < 0.001), hemoglobin A1C level (r = − 0.34, P < 0.001), LDL cholesterol level (r = 0.22, P = 0.009), mitral A velocity (r = − 0.27, P = 0.001) and Tei index (r = − 0.19, P = 0.02), whereas mitral E/A ratio, mitral Em (r = 0.18, P = 0.02), mitral Em/Am ratio (r = 0.23, P = 0.004) were significantly and positively correlated with CFR.

Conclusion

CFR is impaired in subjects with prediabetics, but this impairment is not as severe as that in diabetics.  相似文献   
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