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ObjectiveTo compare the lumen parameters measured by the location-adaptive threshold method (LATM), in which the inter- and intra-scan attenuation variabilities of coronary computed tomographic angiography (CCTA) were corrected, and the scan-adaptive threshold method (SATM), in which only the inter-scan variability was corrected, with the reference standard measurement by intravascular ultrasonography (IVUS).Materials and MethodsThe Hounsfield unit (HU) values of whole voxels and the centerline in each of the cross-sections of the 22 target coronary artery segments were obtained from 15 patients between March 2009 and June 2010, in addition to the corresponding voxel size. Lumen volume was calculated mathematically as the voxel volume multiplied by the number of voxels with HU within a given range, defined as the lumen for each method, and compared with the IVUS-derived reference standard. Subgroup analysis of the lumen area was performed to investigate the effect of lumen size on the studied methods. Bland-Altman plots were used to evaluate the agreement between the measurements.ResultsLumen volumes measured by SATM was significantly smaller than that measured by IVUS (mean difference, 14.6 mm3; 95% confidence interval [CI], 4.9–24.3 mm3); the lumen volumes measured by LATM and IVUS were not significantly different (mean difference, −0.7 mm3; 95% CI, −9.1–7.7 mm3). The lumen area measured by SATM was significantly smaller than that measured by LATM in the smaller lumen area group (mean of difference, 1.07 mm2; 95% CI, 0.89–1.25 mm2) but not in the larger lumen area group (mean of difference, −0.07 mm2; 95% CI, −0.22–0.08 mm2). In the smaller lumen group, the mean difference was lower in the Bland-Altman plot of IVUS and LATM (0.46 mm2; 95% CI, 0.27–0.65 mm2) than in that of IVUS and SATM (1.53 mm2; 95% CI, 1.27–1.79 mm2).ConclusionSATM underestimated the lumen parameters for computed lumen segmentation in CCTA, and this may be overcome by using LATM.  相似文献   
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Hypertrophic lichen planus (HLP) is a T‐cell‐mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24‐year‐old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated.  相似文献   
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TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker.  相似文献   
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BACKGROUND Helicobacter pylori(H.pylori)infection is known to prevent the occurrence of gastroesophageal reflux disease(GERD)by inducing gastric mucosal atrophy.However,little is known about the relationship between atrophic gastritis(AG)and GERD.AIM To confirm the inverse correlation between AG and the occurrence and severity of GERD.METHODS Individuals receiving health checkups who underwent upper gastrointestinal endoscopy at Seoul National University Healthcare System Gangnam Center were included.The grade of reflux esophagitis was evaluated according to the Los Angeles classification.Endoscopic AG(EAG)was categorized into six grades.Serologic AG(SAG)was defined as pepsinogen I≤70 ng/m L and pepsinogen I/II ratio≤3.0.The association between the extent of EAG and SAG and the occurrence and severity of GERD was evaluated using multivariate logistic regression analysis.RESULTS In total,4684 individuals with GERD were compared with 21901 healthy controls.In multivariate logistic regression analysis,advanced age,male sex,body mass index>23 kg/m2,presence of metabolic syndrome,current smoking,and alcohol consumption were associated with an increased risk of GERD.Seropositivity for H.pylori immunoglobulin G antibodies was associated with a decreased risk of GERD.There was an inverse correlation between the extent of EAG and occurrence of GERD:Odds ratio(OR),1.01[95%confidence interval(CI):0.90-1.14]in C1,0.87(0.78-0.97)in C2,0.71(0.62-0.80)in C3,0.52(0.44-0.61)in O1,0.37(0.29-0.48)in O2,and 0.28(0.18-0.43)in O3.Additionally,the extent of EAG showed an inverse correlation with the severity of GERD.The presence of SAG was correlated with a reduced risk of GERD(OR=0.49,95%CI:0.28-0.87,P=0.014).CONCLUSION The extent of EAG and SAG exhibited strong inverse relationships with the occurrence and severity of GERD.AG followed by H.pylori infection may be independently protect against GERD.  相似文献   
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Background

Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.

Methods

A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.

Results

Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.

Conclusions

Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting.  相似文献   
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