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Central pulse pressure is correlated with carotid atherosclerosis and the incidence of cardiovascular events more significantly than brachial pulse pressure. Augmentation index (Aix) has been shown to be an independent predictor of cardiovascular morbidity and mortality. Pulse wave analysis using the Gaon system allows for the estimation of central blood pressure (CBP), corrected augmentation index (Aix@HR75), ejection duration (ED) and subendocardial viability ratio (SEVR), and is widely used in clinical research in Korea. However, the accuracy of this system is controversial. From February 2008 to March 2011, 99 patients were recruited for this study. Measurements were taken both by the Gaon system and the SphygmoCor system on the same day for all study participants. The estimated values of CBP, Aix@HR75, ED and SEVR for the two systems were compared using paired t-tests, simple correlation analyses and Bland-Altman plots. Systolic blood pressure (SBP) estimated by the two systems was significantly (P<0.001) correlated; the coefficient was 0.982. The two s.d. of the difference in SBP between these systems was quite small--<7?mm?Hg. Aix@HR75, ED and SEVR as estimated by the two systems were also significantly correlated, although they, especially SEVR, showed much weaker correlations than were observed in SBP: coefficients for Aix@HR75, ED and SEVR were 0.727, 0.648 and 0.230, respectively. We assessed the CBP of Korean patients estimated by the two systems and observed that the correlations of Aix, ED and SEVR were weaker than that of CBP. Such variations may be due to the difference in measuring methods between the devices. As even a slight change in pulse waveforms may result in a large difference in estimations, parameters, including Aix@HR75, ED and SEVR, should be carefully interpreted by experienced clinicians.  相似文献   
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Background/Aims

Second-look endoscopy is performed to check for the possibility of post-endoscopic submucosal dissection (ESD) bleeding and to perform prophylactic hemostasis in most hospitals; however, there is little evidence about the efficacy of second-look endoscopy. We investigated whether second-look endoscopy after ESD is useful in the prevention of post-ESD bleeding.

Methods

A total of 550 lesions with gastric epithelial neoplasms in 502 patients (372 men and 130 women) were treated with ESD between August 18, 2009 and August 18, 2010. After the exclusion of three lesions of post-ESD bleeding within 24 hours, 547 lesions (335 early gastric cancers and 212 gastric adenomas) were included for the final analysis.

Results

The occurrence rate of delayed post-ESD bleeding was not significantly different between the second-look group and the no second-look group (1% vs 2.5%, p>0.05). The only predictor of delayed bleeding was tumor size, regardless of second-look endoscopy after ESD (22.8±9.87 vs 15.1±10.47, p<0.05). There was no difference between the prophylactic hemostasis and nonprophylactic hemostasis groups, including the occurrence rate of delayed bleeding. In the second-look group with prophylactic hemostasis, the hospital stay was more prolonged than in the second-look group without prophylactic hemostasis, but there was no significant difference (p=0.08).

Conclusions

Second-look endoscopy to prevent delayed bleeding after ESD provides no significant medical benefits.  相似文献   
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Porcine reproductive and respiratory syndrome virus (PRRSV) isolates belonging to the European genotype 1 have recently emerged in South Korea, suggesting potential problems for disease control. In the present study, we attempted to determine the complete nucleotide sequence of the first Korean type 1 PRRSV isolate, designated KNU-07. The full-length genome of KNU-07 was found to be 15,038 nucleotides in length, which was 60 nucleotides shorter than the type 1 prototype strain Lelystad due to a notable 60-bp deletion within the nonstructural protein 2 (NSP2). The KNU-07 genome was shown to consist of a 221-nucleotide (nt) 5′ untranslated region (UTR), a 14,703-nt protein-coding region, and a 114-nt 3′ UTR, followed by a 42-73-bp poly(A) tail. A nucleotide sequence comparison of the KNU-07 genome with 20 complete PRRSV genomes revealed a 10.5–13.3% and 39.5–40.3% divergence from type 1 and type 2 strains, respectively, at the genome level, indicating a high similarity to the virus strains commonly identified as the European genotype. In order to investigate genetic variation and to understand the molecular evolution of the type 1 isolate in Korea, extensive phylogenetic analyses were performed using the ORF5 and ORF7 nucleotide sequences of published type 1 PRRSV isolates. The data further indicated that the newly emerging type 1 isolate KNU-07 belongs to the recently proposed pan-European subtype 1. Taken together, the results of this study describe the genomic characterization of the type 1 PRRSV isolated in South Korea, suggesting a recent introduction of the virus typical for this genotype that has commonly appeared worldwide.  相似文献   
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Problem  Intraperitoneal immuno-inflammatory changes may be associated with the pathogenesis of endometriosis. We evaluated the effects of peritoneal fluid obtained from patients with endometriosis (ePF) on the release of interferon-γ-induced protein-10 (IP-10/CXCL10) and interleukin-8 (IL-8/CXCL8) by neutrophils, CD4+ T cells, and monocytes.
Method of study  Neutrophils, CD4+ T cells, and monocytes were cultured with ePF and the chemokine levels in the supernatants were then measured using enzyme-linked immunosorbent assay.
Results  The addition of ePF to cultures of CD4+ T cells led to a significant increase in the release of IP-10 when compared with control PF without endometriosis (cPF). There was a positive correlation between the levels of IL-8 and IP-10 in ePF ( R  = 0.89, P  =   0.041), but not between the levels of IP-10 and IL-8 released by neutrophils, CD4+ T cells, and monocytes. The levels of IP-10 in ePF were positively correlated with the release of IP-10 by ePF-treated neutrophils ( R  = 0.89, P  <   0.001), CD4+ T cells ( R  = 0.93, P  <   0.001), and monocytes ( R  = 0.70, P  =   0.01). Moreover, the addition of ePF significantly enhanced the interferon-γ-induced release of IP-10 by nuetrophils and CD4+ T cells.
Conclusion  These findings suggest that neutrophils and T cells release differential levels of IP-10 and IL-8 in response to stimulation with ePF, and that these cells are a major source of IP-10 in the PF of endometriosis patients.  相似文献   
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PurposeDissection after plain balloon angioplasty is required to achieve adequate luminal area; however, it is associated with a high risk of vascular events. This study aimed to examine the relationship between non-flow limiting coronary dissections and subsequent lumen loss and long-term clinical outcomes following successful drug-coated balloon (DCB) treatment of de novo coronary lesions.Materials and MethodsA total of 227 patients with good distal flow (Thrombolysis in Myocardial Infarction flow grade 3) following DCB treatment were retrospectively enrolled and stratified according to the presence or absence of a non-flow limiting dissection. The primary endpoint was late lumen loss (LLL) at 6-month angiography, and the secondary endpoint was target vessel failure (TVF, a composite of cardiac death, target vessel myocardial infarction, target vessel revascularization, and target vessel thrombosis).ResultsThe cohort consisted of 95 patients with and 132 patients without a dissection. There were no between-group differences in LLL (90.8%) returning for angiography at 6 months (0.05±0.19 mm in non-dissection and 0.05±0.30 mm in dissection group, p=0.886) or in TVF (6.8% in non-dissection and 8.4% in dissection group, p=0.799) at a median follow-up of 3.4 years. In a multivariate analysis, the presence of dissection and its severity were not associated with LLL or TVF. Almost dissections (93.9%) were completely healed, and there was no newly developed dissection at 6-month angiography.ConclusionThe presence of a dissection following successful DCB treatment of a de novo coronary lesion may not be associated with an increased risk of LLL or TVF (Impact of Drug-coated Balloon Treatment in de Novo Coronary Lesion; {\"type\":\"clinical-trial\",\"attrs\":{\"text\":\"NCT04619277\",\"term_id\":\"NCT04619277\"}}NCT04619277).  相似文献   
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Targeted application of next-generation sequencing (NGS) technology allows detection of specific mutations that can provide treatment opportunities for cancer patients. We evaluated the applicability of the Ion AmpliSeq Cancer Hotspot Panel V2 (CHV2) using formalin-fixed, paraffin-embedded (FFPE) tissue of clinical specimens.Thirty-five FFPE tumour samples with known mutational status were collected from four different hospitals and sequenced with CHV2 using an Ion Chef System and Ion S5 XL system. Out of 35 cases, seven were sequenced with Oncomine focus Assay Panel for comparison. For the limit of detection test, we used an FFPE reference standard, a cell line that included an engineered 50% EGFR T790?M in an RKO cell line background. Coverage analysis results including number of mapped reads, on target percent, mean depth, and uniformity were not different according to hospitals. Sensitivity for mutation detection down to 3% was demonstrated. NGS results showed 100% concordance with the results from single molecular pathology tests Assay in 30 cases with 24 known positive mutations and 14 known negative mutations, and another NGS panel of the Oncomine focus in seven cases.The CHV2 NGS test for solid tumours using Ion chef system and S5 XL system in clinical molecular pathology laboratories for analysis of solid tumours could be routinely used and could replace some single molecular pathology tests after a stringent and thorough validation process.  相似文献   
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