Influence of concomitant percutaneous transluminal angioplasty with percutaneous coronary intervention on outcomes in patients with stable lower extremity artery disease

Background

Patients with stable lower extremity artery diseases (LEAD) frequently present with coronary artery diseases; thus, concomitant percutaneous transluminal angioplasty (PTA) at the time of percutaneous coronary intervention (PCI) is often performed. We investigated the influence of concomitant PTA on both cardiovascular (CV) and limb outcomes in the Korean National Health Insurance Service registry.

Methods

Among 78,185 patients undergoing PCI between 2012 and 2015, 6,563 patients (279 for the PTA+PCI group vs. 6,284 for the PCI group) suffering from stable LEAD without limb ischemia were included. Major adverse CV events (MACEs) were defined as a composite of CV death, myocardial infarction (MI) and coronary revascularization. Patients were followed for at least 3 years.

Results

After 1:5 propensity score matching was conducted, 279 patients in the PTA+PCI group and 1,385 patients in the PCI group were compared. The risk of all-cause death was higher in the PTA+PCI group than in the PCI group, whereas the risks of MACE, MI, revascularization, stroke, CV death and bleeding event were not different between the 2 groups in the matched cohort. In contrast, the risks of end-stage renal diseases and unfavorable limb outcomes were higher in the PTA+PCI group than in the PCI group (Figure 1). Mediation analyses revealed that amputation and repeat Percutaneous transluminal angioplasty after discharge significantly mediated the association between the concomitant PTA and all-cause death (Figure 2).

Conclusions

CPTA at the time of PCI is not associated with an increased risk of CV events but may increase the risk of all-cause death by increasing unfavorable renal and limb outcomes in patients with stable LEAD.

Funding Acknowledgement

Type of funding sources: None.

A data-driven Bayesian network for probabilistic crash risk assessment of individual driver with traffic violation and crash records

In recent years, individual drivers' crash risk assessments have received much attention for identifying high-risk drivers. To this end, we propose a probabilistic assessment method of crash risks with a reproducible long-term dataset (i.e., traffic violations, license, and crash records). In developing this method, we used 7.75 million violations and crashes of 5.5 million individual drivers in Seoul, South Korea, from June 2013 to June 2017 (four years). The stochastic process of the Bayesian network (BN), whose structure is optimized by tabu-search, successfully evaluates individual drivers' crash and violation probability. In addition, the cluster analysis classifies drivers into five distinctive groups according to their estimated violation and crash probabilities. As a result, this study found that the estimated average crash rate within a cluster converges with the actual crash rate by the proposed framework without privacy issues. We also confirm that violation records and expected crash probability are strongly correlated, and there is a direct relationship between a driver's previous violations and crash record and the future at-fault crash. The proposed assessment method is valuable in developing proactive driver education programs and safety countermeasures, including adjusting the penalty system and developing user-based insurance by recognizing dangerous drivers and identifying their properties.

Associations between changing patterns of ST-T waves morphologies in rest electrocardiography and cardiovascular risk in an asymptomatic low risk population: a report from Ansan-Ansung cohort study

Background

While clinical significance of ST-T wave abnormalities (STA) in rest electrocardiography (ECG) on long-term cardiovascular outcomes has been on debate, few studies have been reported on the association between the changes in ST-T waves in rest ECG and cardiovascular outcomes in low risk populations. We investigate the changing patterns of STA in rest ECG and the predictive value of the changes in ST-T wave in rest ECG for cardiovascular events in an asymptomatic general population.

Methods

A longitudinal community-based cohort study was conducted for 12 years. Koreans aged 40–69 years were followed biennially through scheduled revisit for comprehensive assessments. Among 10,030 participants, 6,648 participants who did not have any cardiovascular diseases, angina-related symptoms or pathologic Q waves in rest ECG at baseline were included for analysis. Changes in STAs were defined using the changes between ECG at baseline and that at the first revisit. A major adverse cardiovascular events was defined as a composite of cardiac death, myocardial infarction, clinical diagnosis of coronary artery disease and stroke.

Results

Among 5,924 participants without STA at baseline, only 187 participants (3.2%) developed new STA. Among 724 patients (10.9%) with STA at baseline, 274 patients (37.8%) persistently showed STA at the first revisit. MACEs occurred more frequently in the participants persistently with STA and those with newly-developed STA than in the participants persistently without STA (Figure 1). Multivariate Cox-proportional hazard models showed that a higher risk of MACE was only associated with the persisted STA (HR 1.69; 95% CI 1.10–2.63). In participants with baseline STA, persisted T-wave flattening was associated with a higher risk of MACE, whereas T-wave inversion, either persisted or fluctuated was not associated with a higher risk of MACE, compared with persistent absence of STA (Figure 2). In the participants without baseline STAs, multivariate Cox-proportional hazard model showed that newly-developed T-wave flattening (HR 1.85; 95% CI 0.20–2.84), not T-wave inversion (HR 1.50; 95% CI 0.85–2.65) was associated with a higher risk of MACE. Survival receiver operating curve analysis showed that the changes in STAs had a C-index of 0.538 (95% CI 0.511–0.558), a sensitivity of 13.0% and a specificity of 92.5% and add only a small value to the predictive power of 10-year atherosclerotic cardiovascular diseases risk estimator (C-index without STA changes 0.708 [0.681–0.736] vs. C-index with STA changes 0.721 [0.694–0.748]).

Conclusions

STAs uncommonly developed while frequently disappeared spontaneously in the asymptomatic general population. Persisted STA and newly developed STA in rest ECG were predictive of future cardiovascular events in the asymptomatic general population. However, the changes in STAs did not significantly improve the predictive value of the conventional risk estimator, when added.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research Foundation of Korea Figure 1Figure 2

Simulation and validation for count-based binary decision of target blood pressure achievement in home blood pressure monitoring data analysis for clinical practice

Introduction

Home blood pressure monitoring (HBPM) is a useful tool to identify hypertension and to decide whether a patient's blood pressure (BP) is controlled. The use of automatized oscillometric BP measurement devices has become increasingly popular with help of information technology and internet of things to the devices. However, applying HBPM to daily clinical practices is still challenging, because most patients with hypertension are in age groups not familiar to digital devices and internet and high BP criteria using average home BP values are often useless in outpatient clinics without easily accessible average BP calculation tools. Therefore, we developed a simple and straightforward method to interpret HBPM through counts of BP ≥135/85 mmHg.

Methods

We simulated 400 cases of HBPM using a random number generator function in statistical software. The simulated average home systolic BP (SBP) and its standard deviation (SD) were 125±15 mmHg and 12±5 mmHg and the number of HBP readings was 24 times. The simulated diastolic BP (DBP) was randomly selected to 50–75% of the SBP. The validation of the binary interpretation method was conducted using actual HBPM data from 386 subjects in a rural area of South Korea. Receiver operating characteristics curve analysis was conducted, and linear regression and logarithmic models were fitted between the numbers of home BP ≥135/85 mmHg and mean BP. Hypertension was defined with average home BP ≥135/85 mmHg.

Results

In the simulated cohort, hypertension was presented in 197 cases (49.3%). The C-index of the numbers of BP readings ≥135/85 mmHg was 0.994 (95% confidence interval [CI] 0.990–0.998), and ≥12 of 24 BP readings ≥135/85 mmHg showed a sensitivity of 95.4%, a specificity of 95.1% and an accuracy of 95.3% for the diagnosis of hypertension. In validation cohort, the numbers of home BP measurements varied from 8 to 81 times. The validation cohort similarly showed that the C-index of the ratio between the number of high BP readings (≥135/85 mmHg) to the number of BP measurements (R-NHBP/NBP) was 0.985 (95% CI, 0.976–0.994) and the best accuracy was shown at R-NHBP/NBP of ≥0.45. R-NHBP/NBP of ≥0.5 showed a sensitivity of 0.957, a specificity of 0.907 and an accuracy of 0.927. The accuracy of the R-NHBP/NBP of ≥0.5 decreased as SD and the range of SBP increased, whereas it did not change with the number of measurements (Figure 1). R-NHBP/NBP <0.2 predicted normotension and R-NHBP/NBP >0.8 predicted hypertension in 95% confidence. Mean widths of the 95 prediction intervals for the average SBP and DBP were 18.2 mmHg and 12.6 mmHg, respectively (Figure 2).

Conclusion

Counting the number of BP ≥135/85 mmHg can provide accurate assessments for the BP levels. R-NHBP/NBP of ≥0.5 is a simple and accurate marker of high BP in HBPM, and R-NHBP/NBP could be a useful tool to assess BP levels in patients practicing HBPM.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

AtMPK6-induced phosphorylation of AtERF72 enhances its DNA binding activity and interaction with TGA4/OBF4 in Arabidopsis

The ethylene-responsive element binding factor (ERF) family is a large family of transcription factors involved in plant development and environmental stress responses. We previously reported the identification of 29 putative substrates of Mitogen-activated Protein Kinase3 (AtMPK3), AtMPK4 and AtMPK6, based on a solid-phase phosphorylation screening using a lambda phage expression library in Arabidopsis thaliana. In this study, a putative MPK substrate, AtERF72 (At3g16770), was strongly phosphorylated by AtMPK6 on the serine residue at position 151 (Ser151). AtERF72 binds to the GCC box (AGCCGCC) in the promoters of several pathogenesis-related (PR) genes and activates their transcription. We also show that the DNA-binding activity of AtERF72 is enhanced upon phosphorylation by AtMPK6 in vitro. In addition, transient co-expression experiments in Arabidopsis protoplasts revealed that effector constructs expressing a mutant variant of AtERF72, AtERF72^S151D (carrying a Ser to aspartic acid [Asp] substitution at amino acid position 151) showed higher expression of the β-glucuronidase (GUS) reporter gene driven by the GCC box element than effector constructs expressing the wild-type AtERF72. Furthermore, yeast two-hybrid assays revealed that the interaction between AtERF72^S151D and TGA4/OBF4 was stronger than that between wild-type AtERF72 and TGA4/OBF4. Since AtERF72^S151D is equivalent to AtERF72 phosphorylated by AtMPK6 at Ser151, these results suggest that the phosphorylation of AtERF72 by AtMPK6 triggers an event of transcriptional regulation from defence signalling in Arabidopsis.

Risk factors and renal outcomes of low bone mineral density in patients with non-dialysis chronic kidney disease

Bone disorder is a common complication of chronic kidney disease (CKD). The clinical usefulness of bone mineral density (BMD) in CKD is not well known. Our study shows that low BMD is associated with physical activity and dietary Na/K intake ratio and can predict poor renal outcome in non-dialysis CKD.

PURPOSE

Despite evidence of a link between bone mineral disorders and chronic kidney disease (CKD), the clinical implications of bone mineral density (BMD) in CKD are not well established. We investigated risk factors and renal outcomes of low BMD in CKD.

METHODS

We analyzed data from the KNOW-CKD. BMD measured by dual-energy x-ray absorptiometry was classified by T score: normal (T score ≥ - 1.0), osteopenia (- 1.0 > T score > - 2.5), and osteoporosis (T score ≤ - 2.5) of the lumbar spine, hip, or femoral neck. Logistic regression analysis to assess risk factors of low BMD (T score < - 1.0) and Cox proportional hazards models to estimate risk of incident end-stage renal disease (ESRD).

RESULTS

Low BMD was prevalent (osteopenia 33%; osteoporosis 8%) in 2128 adults with CKD (age 54 ± 12 years; male 61%). Over a median follow-up of 4.3 years, there were 521 cases of incident ESRD. Lower BMD was associated with female sex, older age, low eGFR, low BMI, and lifestyle factors of physical activity (odds ratio (OR) = 0.62, 95% confidence interval (0.49-0.77)) and spot urine Na/K ratio (1.07 (1.00-1.15)). In adjusted Cox models, low BMD was associated with increased incident ESRD (hazard ratio (HR) = 1.14 (0.92-1.41) for osteopenia; 1.43 (1.01-2.04) for osteoporosis, P for trend < 0.05) compared with the reference of normal BMD. The association between low BMD and ESRD was similar according to T score discordance classification.

CONCLUSIONS

Low BMD was associated with modifiable lifestyle factors including low physical activity and high dietary Na/K intake ratio. The presence of low BMD is associated with poor renal outcomes in non-dialysis CKD.

Multiple membership multilevel model to estimate intersection crashes

Numerous studies have developed intersection crash prediction models to identify crash hotspots and evaluate safety countermeasures. These studies largely considered only micro-level crash contributing factors such as traffic volume, traffic signals, etc. Some recent studies, however, have attempted to include macro-level crash contributing factors, such as population per zone, to predict the number of crashes at intersections. As many intersections are located between multiple zones and thus affected by factors from the multiple zones, the inclusion of macro-level factors requires boundary problems to be resolved. In this study, we introduce an advanced multilevel model, the multiple membership multilevel model (MMMM), for intersection crash analysis. Our objective was to reduce heterogeneity issues between zones in crash prediction model while avoiding misspecification of the model structure. We used five years of intersection crash data (2009-2013) for the City of Regina, Saskatchewan, Canada and identified micro- and macro-level factors that most affected intersection crashes. We compared the fitting performance of the MMMM with that of two existing models, a traditional single model (SM) and a conventional multilevel model (CMM). The MMMM outperformed the SM and CMM in terms of fitting capability. We found that the MMMM avoided both the underestimation of macro-level variance and the type I statistical error that tend to occur when the crash data are analyzed using a SM or CMM. Statistically significant micro-level and macro-level crash contributing factors in Regina included major roadway AADT, four legs, traffic signals, speed, young drivers, and different types of land use.

Uremic solutes of indoxyl sulfate and p-cresol enhance protease-activated receptor-2 expression in vitro and in vivo in keratinocytes

OBJECTIVES

Uremic pruritus is common in patients with chronic kidney disease (CKD). The retention of uremic solutes is thought to be associated with uremic pruritus. Meanwhile, activation of protease-activated receptor-2 (PAR-2) has been suggested to play an important role in pruritus. The present study was performed to investigate the effects of uremic solutes on the expression of PAR-2 in the skin.

METHODS

Indoxyl sulfate (IS), p-cresol (PC), and uremic sera from CKD patients were used to stimulate PAR-2 expression in normal human epidermal keratinocytes (NHEKs). Also, NHEKs were additionally pretreated with soybean trypsin inhibitor to evaluate its inhibitory effect on PAR-2 expression. Patterns of cutaneous PAR-2 expression were investigated in skin samples from five CKD patients and CKD mice.

RESULTS

In NHEKs, IS, PC, and sera from CKD patients significantly induced PAR-2 mRNA and protein expression. Soybean trypsin inhibitor significantly decreased PAR-2 mRNA and protein expression in NHEKs treated with IS, PC, and CKD sera. NHEKs treated with IS and PC exhibited significant increases in protease activity. Skin from both CKD patients and mice exhibited marked upregulation of PAR-2 expression compared to control skin.

CONCLUSIONS

Results from the present study suggest that uremic solutes either directly or indirectly affect PAR-2 expression in the skin of CKD subjects, potentially playing an important role in the pathogenesis of uremic pruritus.

P5298Influence of the changes in body fat on all-cause and cardiovascular mortality in a general population: a report from Ansan-Ansung cohort in the Korean genome environment study

Background

Paradoxical beneficial effects of obesity on all-cause and cardiovascular mortality have been reported in multiple cohort studies based on patients with cardiovascular disease as well as general populations. However, the association between the presence of obesity at baseline and the better survival rates could not be directly interpreted into the beneficial effect of gain in obesity or fatness on the mortality, which makes it difficult to provide any recommendation for the management of obesity. Therefore, we investigated the influence of the changes in body fat on all-cause and cardiovascular mortality in a general population.

Methods

A population-based cohort study has been conducted for 12 years (from 2001 to 2012). A total of 5,259 subjects in whom body compositions using a bio-impedance method were measured at least 2 times during the observational period were included. The causes of death was identified from the nation-wide database in KOSTAT. I20-I82 and R99 in the International Classification of Disease-10 codes were defined as a cardiovascular death. The subjects were evenly divided into 3 groups by the percentages of the changes in body fat (Δ%BF; decreased [Δ%BF <0.0%] vs. increased [Δ%BF 0.0–13.7%] vs. highly increased [Δ%BF ≥13.7%]). Inverse probability of treatment weighting was applied to balance the covariate differences among the groups.

Results

The age was 51.2±8.5 years and 51.6% was male. Median observation duration was 163 (the interquartile range: 157–168) months. The all-cause death and cardiovascular death occurred most frequently in the decreased Δ%BF group and least frequent in the highly increased Δ%BF group in both unweighted and weighted cohort. Multivariate Cox proportional hazard models showed that the risk of all-cause death was lower in the increased and highly increased Δ%BF groups (hazard ratio [HR] 0.61 [0.47–0.80] and 0.24 [0.17–0.34], respectively) and the risk of cardiovascular death was lower in the highly increased Δ%BF group (HR 0.20 [0.08–0.48]), compared to those in the decreased Δ%BF group after adjustment for all covariates including physical activities and the changes in muscle mass. The risk of all-cause death and cardiovascular death linearly decreased with increasing Δ%BF (HR 0.72 [0.67–0.77] and 0.70 [0.60–0.82], respectively).

Conclusion

The increase in body fat is associated with a lower risk of all-cause death and cardiovascular death in a middle-age general population, independently with physical activities and the changes in muscle mass.

Effect of saphenous vein diameter and reflux time on stump length after cyanoacrylate closure

Cyanoacrylate closure (CAC) has recently been introduced for the treatment of incompetent saphenous veins. The purpose of the present study is to investigate the correlation of the saphenous vein diameter and reflux time (RT) with the stump length after CAC. A retrospective review was performed using prospectively collected data of CAC patients. The pre-operative saphenous vein diameter and RT were measured. The stump length was measured immediately after the procedure and at 1 week. Pearson's correlation analysis was applied to determine the correlation between the saphenous vein diameter or RT and stump length. A total of 32 saphenous veins were closed in 21 patients, 15 of whom were female. The mean age was 56.9±12.6 years (range, 31-73 years). Complete closure was achieved in all patients. The pre-operative mean diameter was 7.0±2.2 mm. The mean stump lengths were 26.1±10.2 and 28.1±13.6 mm on post-operative days 0 and 7, respectively (P=0.002). The Pearson coefficients for the correlation between the saphenous vein diameter and stump length on post-operative days 0 and 7 were 0.528 (P=0.005) and 0.177 (P=0.430), respectively. Furthermore, the Pearson coefficients for the correlation between the RT and stump length on post-operative days 0 and 7 were -0.215 (P=0.282) and 0.019 (P=0.938), respectively. In conclusion, CAC is effective modality for the treatment of saphenous vein insufficiency. The stump length increased with the diameter of the saphenous veins, while the RT had no marked effect on the stump length. Therefore, the glue injection should be initiated from the instructed position to avoid glue extension into deep veins and to prevent elongating the stump length.

Effects of triethylene glycol dimethacrylate and hydroxyethyl methacrylate on macrophage polarization

AIM

To evaluate the effects of hydrophilic dental resin monomers, triethylene glycol dimethacrylate (TEGDMA) and hydroxyethyl methacrylate (HEMA), on the polarization of a human monocyte cell line (THP-1).

METHODOLOGY

THP-1 cells were treated with resin monomers at noncytotoxic concentrations for 48 h and were analysed for CD86 and CD206 expressions using flow cytometry. The cells were stimulated for polarization in the presence of resin monomers (co-treatment) or after treatment with monomers (pre-treatment). CD86 and CD206 mRNA in co-treated cells was evaluated using quantitative real-time polymerase chain reaction. The release of TNF-α and TGF-β by pre-treated and co-treated cells was assessed using enzyme-linked immunosorbent assay. Morphological changes of macrophages during polarization were observed using bright-field microscopy. One-way analysis of variance was used for statistical analysis.

RESULTS

TEGDMA (1 mmol L^-1 ) and HEMA (2 mmol L^-1 ) did not induce CD86 and CD206 expressions in THP-1 cells but rather inhibited their expressions in the co-treated cells. The inhibitory effects also appeared at the transcription level. However, the expression of surface markers was not affected by pre-treatment with resin monomers. The release of TNF-α and TGF-β by M1- and M2-stimulated cells, respectively, was suppressed by co-treatment (P < 0.05). Microscopic studies revealed that co-treatment with resin monomers suppressed polarization-associated morphological changes such as cell volume increase.

CONCLUSIONS

TEGDMA and HEMA inhibited macrophage polarization to both M1 and M2 at the transcription level, and the inhibitory effects disappeared upon the removal of resin monomers from the cell culture.

Temporal Control of WNT Activity Regulates Tooth Number in Fish

Wnts determine cell polarity, cell proliferation, and cell differentiation during embryogenesis and play an essential role during tooth development initiation and morphogenesis. Wnt/β-catenin signaling has a time-dependent role in development because various signaling molecules that mutually interact are involved in the pathway, and tight regulation of the pathway is essential for normal development. Studies investigating how the Wnt/β-catenin signaling pathway controls the different stages of tooth development are rare. Specifically, the effects of Wnt/β-catenin signaling loss of function on different stages of tooth development are currently unknown. Here, we report the stage-dependent role of Wnt/β-catenin signaling in tooth development. In vivo loss and gain of function of Wnt/β-catenin signaling were implemented through the genetic overexpression of DKK1 with heat shock-inducible transgenic models and the pharmacologic inhibition of β-catenin destruction complex formation in zebrafish, respectively. We demonstrated that transient inhibition of Wnt/β-catenin signaling interrupted tooth development in a stage-dependent manner and conditional activation of Wnt/β-catenin signaling during 4V morphogenesis inhibited the development of 3V. These findings suggest that Wnt/β-catenin signaling plays an important role in the morphogenesis of teeth and the initiation of sequential tooth development in a stage-dependent manner.

Randomized clinical trial of antibiotic therapy for uncomplicated appendicitis

Background

Uncomplicated appendicitis may resolve spontaneously or require treatment with antibiotics or appendicectomy. The aim of this randomized trial was to compare the outcome of a non-antibiotic management strategy with that of antibiotic therapy in uncomplicated appendicitis.

Methods

Patients presenting to a university teaching hospital with CT-verified uncomplicated simple appendicitis (appendiceal diameter no larger than 11 mm and without any signs of perforation) were randomized to management with a no-antibiotic regimen with supportive care (intravenous fluids, analgesia and antipyretics as necessary) or a 4-day course of antibiotics with supportive care. The primary endpoint was rate of total treatment failure, defined as initial treatment failure within 1 month and recurrence of appendicitis during the follow-up period.

Results

Some 245 patients were randomized within the trial, and followed up for a median of 19 months. The duration of hospital stay was shorter (mean 3·1 versus 3·7 days; P &lt; 0·001) and the medical costs lower (€1181 versus 1348; P &lt; 0·001) among those randomized to therapy without antibiotics. There was no difference in total treatment failure rate between the groups: 29 of 124 (23·4 per cent) in the no-antibiotic group and 25 of 121 (20·7 per cent) in the antibiotic group (P = 0·609). Eighteen patients (9 in each group) had initial treatment failure, 15 of whom underwent appendicectomy and three received additional antibiotics. Thirty-six patients (20 in the no-antibiotic group, 16 in the antibiotic group) experienced recurrence, of whom 30 underwent appendicectomy and six received further antibiotics.

Conclusion

Treatment failure rates in patients presenting with CT-confirmed uncomplicated appendicitis appeared similar among those receiving supportive care with either a no-antibiotic regimen or a 4-day course of antibiotics. Registration number: KCT0000124 (http://cris.nih.go.kr).

Cross-classified multilevel models for severity of commercial motor vehicle crashes considering heterogeneity among companies and regions

This study analyzes 86,622 commercial motor vehicle (CMV) crashes (large truck, bus and taxi crashes) in South Korea from 2010 to 2014. The analysis recognizes the hierarchical structure of the factors affecting CMV crashes by examining eight factors related to individual crashes and six additional upper level factors organized in two non-nested groups (company level and regional level factors). The study considers four different crash severities (fatal, major, minor, and no injury). The company level factors reflect selected characteristics of 1,875 CMV companies, and the regional level factors reflect selected characteristics of 230 municipalities. The study develops a single-level ordinary ordered logit model, two conventional multilevel ordered logit models, and a cross-classified multilevel ordered logit model (CCMM). As the study develops each of these four models for large trucks, buses and taxis, 12 different statistical models are analyzed. The CCMM outperforms the other models in two important ways: 1) the CCMM avoids the type I statistical errors that tend to occur when analyzing hierarchical data with single-level models; and 2) the CCMM can analyze two non-nested groups simultaneously. Statistically significant factors include taxi company's type of vehicle ownership and municipality's level of transportation infrastructure budget. An improved understanding of CMV related crashes should contribute to the development of safety countermeasures to reduce the number and severity of CMV related crashes.

Ultrasound fusion imaging with real-time navigation for the surveillance after endovascular aortic aneurysm repair

Ultrasound can be an effective alternative to computed tomography for surveillance following endovascular aneurysm repair (EVAR). Recently, ultrasound fusion imaging with the real-time navigation system was introduced. Here we described 3 patients who underwent post-EVAR surveillance using this novel technique. Complete coregistration was achieved in all patients. The origin of left renal artery was selected for the target of coregistration. Ultrasound fusion imaging was useful to differentiate the confusing lesion and to evaluate the complete resolution of endoleak and newly developed delayed endoleak. Ultrasound fusion image with real-time navigation system can be a feasible imaging tool for post-EVAR surveillance.

Effects of cell death-inducing DFF45-like effector B on meat quality traits in Berkshire pigs

Cell death-inducing DFF45-like effector (CIDE) B is a member of the CIDE family of apoptosis-inducing factors. In the present study, we detected a single nucleotide polymorphism (SNP), c.414G>A, which corresponds to the synonymous SNP 414Arg, in CIDE-B in the Berkshire pigs. We also analyzed the relationships between the CIDE-B SNP and various meat quality traits. The SNP was significantly associated with post-mortem pH_24h, water-holding capacity (WHC), fat content, protein content, drip loss, post-mortem temperature at 12 h (T12) and 24 h (T24) in a co-dominant model (P < 0.05). A significant association was detected between the SNP and post-mortem pH_24h, fat content, protein content, drip loss, shear force, and T24 in gilts; and color parameter b*, WHC, and T24 in barrows (P < 0.05). The SNP was significantly correlated with the fat content, and CIDE-B mRNA expression was significantly upregulated during the early stage of adipogenesis, suggesting that CIDE-B may contribute towards initiation of adipogenesis (P < 0.05). Furthermore, CIDE-B mRNA was strongly expressed in the liver, kidney, large intestine, and small intestine, and weakly expressed in the stomach, lung, spleen, and white adipose tissue. These results indicate that the CIDE-B SNP is closely associated with meat quality traits and may be a useful DNA marker for improving pork quality.

Anatomic and clinical risk factors for pulmonary embolism in patients with deep venous thrombosis of the lower extremity

Purpose

Iliac vein compression is a known culprit of deep vein thrombosis (DVT). In contrast, the compression may prevent the pulmonary embolism (PE). The aim of this study was to evaluate the anatomic and clinical risk factors of PE in patients with lower extremity DVT.

Methods

PE was evaluated using chest computed tomography in patients with lower extremity DVT. The patients were classified into group I (DVT without PE) and group II (DVT with PE) and analyzed to clarify the anatomic and clinical risk factors associated with PE in patients with DVT. As the anatomic factor, the shortest length between the common iliac artery (CIA) and spinal body (SB) was measured. Statistical analyses utilized the multivariable logistic regression model, and receiver operating characteristic (ROC) curve analysis.

Results

We examined 114 patients (age; 62.7 ± 16.9 years, 41.7% men) with DVT with/without PE. The prevalence of concurrent DVT with PE was 52.6%. Blood tests showed no difference between the 2 groups. Of all the assessed patients' characteristics, only infection was significantly and independently associated with PE (P = 0.04). The shortest length between CIA and SB was 6.7 ± 3.5 mm in group I and 11.3 ± 3.7 mm in group II (P < 0.001). ROC curve analysis showed that 7.6 mm was the cut-off value for the anatomic risk of PE.

Conclusion

Infection was significantly associated with concurrent DVT and PE. The shortest length between CIA and SB (<7.6 mm) may prevent PE in patients with DVT.

The Usefulness of Duplex Ultrasound for Hemodialysis Access Selection

Purpose

A native vessel is preferable to an artificial graft for dialysis access. Duplex ultrasound (DUS) is noninvasive, cost-effective modality to evaluate the vessels for dialysis. The purpose of this study was to compare the rates of utilization of native vessels after preoperative imaging with DUS and contrast venography (CV).

Materials and Methods

A retrospective review was performed on patients who received an arteriovenous fistula (AVF) or arteriovenous graft (AVG) between June 2006 and July 2010. Patients were classified into 3 groups. In group 1, CV was used to evaluate the vessel. Both DUS and CV were used in group 2. In group 3, only DUS was used. The frequency of utilization of a native vessel was analyzed in each group. The chi-square test was used for statistical analysis.

Results

During the study period, 173 patients received an AVF or AVG. Eighty-nine patients were male. The mean age was 60.6±14.6 years. A native vessel was used in 56/81 patients (69.1%) and 74/81 patients (91.4%) in groups 1 and 3, respectively (P<0.001). In group 2, all patients underwent access procedures using native vessels. AVG was initially planned for 2 patients in group 2 after vessel evaluation using CV, but a native vessel was successfully used because DUS identified optimal vessels for AVF. The 1-year primary patency rate was similar in 3 groups.

Conclusion

Preoperative DUS is safe and easy to use for vessel evaluation, and can be used as a primary imaging modality for creation of access.

Measuring of Abdominal Aortic Aneurysm with Three-Dimensional Computed Tomography Reconstruction before Endovascular Aortic Aneurysm Repair

PURPOSE

Conventional computed tomography (CT) is the gold standard method for case planning for endovascular aortic aneurysm repair (EVAR). However, aortography with a marking catheter is needed for measuring the actual length of an aneurysm. With advances in imaging technology, a 3-dimensional (3D) workstation can obviate the need for the aortography. The objective of this study was to determine whether a 3D workstation could obviate the need for aortography for EVAR.

MATERIALS AND METHODS

One vascular surgeon and 1 interventional radiologist retrospectively assessed axial CT scans and reformatted the 3D CT scans by using the iNtuition workstation (TeraRecon Inc., San Mateo, CA, USA) for 25 patients who underwent EVAR. Four measurements of diameter and length were obtained from each modality. The actual length of an aneurysm for the proper graft was decided by 2 observers by reviewing the aortography with a marking catheter.

RESULTS

The measurements from the 2 modalities were reproducible with intraobserver correlation coefficients of 0.89 to 1.0 for conventional CT and 0.98 to 1.0 for 3D workstation. Interobserver correlation coefficients were 0.29 to 0.95 for conventional CT and 0.85 to 0.99 for the 3D workstation. The length of the aneurysm for proper main graft coincided in 18 and 14 patients according to the conventional CT scan and in 21 and 18 patients according to the 3D workstation, respectively.

CONCLUSION

The interobserver agreement in planning EVAR was significantly better with the iNtuition 3D workstation. But aortography with a marking catheter may still be needed for selecting the proper graft.

Prevalence and risk factors for atherosclerotic carotid stenosis and plaque: A population-based screening study

Atherosclerotic carotid stenosis (ACS) is a major cause of ischemic stroke. Screening for asymptomatic ACS is important to identify the patients who require longitudinal surveillance, medication, or endovascular surgery. The aim of this study was to assess the prevalence and risk factors for ACS and carotid plaque (CP) in Korea using a population-based screening study.We recruited participants during visits to several community welfare centers in Korea. The baseline characteristics of the study population were collected. All patients underwent duplex ultrasonography to examine their bilateral carotid arteries. ACS was defined as the presence of plaque with ≥50% vessel diameter reduction and peak systolic velocity (PSV) ≥125 cm/s or PSV ratio ≥2.0. CP was defined as the presence of plaque with <50% vessel diameter reduction. The Mann-Whitney test, χ test, Fisher exact test, and logistic regression were used in the statistical analysis.A total of 3030 participants were enrolled in this study (male 43.7% and female 56.3%). The prevalence of ACS and CP was 1.1% and 5.7%, respectively. Significant risk factors for CP included age ≥80 years (odds ratio [OR], 8.11; 95% confidence interval [CI], 3.45-18.93), male sex (OR, 2.16; 95% CI, 1.29-3.61), hypertension (OR, 1.72; 95% CI, 1.21-2.45), and hyperlipidemia (OR, 1.84; 95% CI, 1.30-2.62). The presence of ACS was significantly associated with age (OR, 1.07; 95% CI, 1.03-1.12), hypertension (OR, 3.16; 95% CI, 1.34-7.46), and being an ex-smoker (OR, 6.81; 95% CI, 1.66-27.93) or current smoker (OR, 6.97; 95% CI, 1.78-27.31) after adjusting for confounding factors.This population-based screening study revealed that ACS was uncommon and had a prevalence of 1.1% in the study population. Age, hypertension, and smoking were risk factors for ACS. Further investigations into the prevalence and risk factors of ACS are required, as are studies on the cost-effectiveness of a national screening program.

Development of the dual SMART micro-surgical system using common-path swept source optical coherence tomography

Manual micro-surgical tasks are fundamentally divided into grasping, cutting and injecting maneuvers performed on biological tissues. Efficient dissection of fibrous tissue from the surface of the retina often requires grasping and cutting maneuvers carried out simultaneously. True bimanual surgery requires that the surgeon contend with the innate hand tremor of two hands at once as well as unpredicted patient's movement. In this study, we develop and test a dual SMART micro-surgical system to suppress bimanual hand tremor during micro-surgical dissection.

National trends for open and endovascular repair of aneurysms in Korea: 2004-2013

The introduction of endovascular aneurysm repair has led to a dramatic decline in open aneurysm repair. The aim of this report was to evaluate Korean national trends for the treatment of aneurysms. A serial, cross-sectional study of time trends of patients who underwent aneurysm repair between 2004 and 2013 was conducted. Data from the Health Insurance Review and Assessment Service were used to evaluate the trends of aneurysm repair in the Korean population and to analyze the trends of open and endovascular aneurysm repair among Medicare beneficiaries. A linear-by-linear association was performed to determine alterations in the rates at which these aneurysm repair techniques were performed. A total of 32,130 patients underwent aneurysm repair between 2004 and 2013. The proportion of patients who underwent open repair decreased from 94.0% in 2004 to 54.9% in 2013; whereas the proportion of patients who underwent endovascular repair increased from 6.0% in 2004 to 45.1% in 2013. During the study period, the number of patients undergoing endovascular repair of aortic aneurysms significantly increased from 82 to 1,396 (relative risk, 16.17; 95% confidence interval: 12.94-20.21). Endovascular repair of abdominal aortic aneurysms (AAAs)overtook open repair between 2010 and 2011. The frequency of open aneurysm repair increased 1.2-fold, with an overall downward trend. The prevalence of endovascular repair markedly increased 15.3-fold. These findings indicated that, in Korea, the endovascular repair of AAAs overtook open repair as the most common technique between 2010 and 2011.

National trends in carotid endarterectomy and stenting in Korea from 2004 to 2013

Stroke imposes a substantial clinical and socioeconomic burden. Carotid endarterectomy (CEA) or carotid artery stenting (CAS) are proven procedures in stroke prevention for the lesions of extracranial carotid disease. Although several studies have addressed national trends regarding carotid revascularization in Western countries, limited data is available with respect to the Korean population. The aim of the present study was to identify the national trend in carotid revascularization in Korea over the previous decade. A serial, cross-sectional study was conducted with the use of time trends to analyze patients undergoing carotid revascularization using CEA and CAS between 2004 and 2013. Health Insurance Review and Assessment Service data was used. The present study endeavored to analyze trends in the number of CEA and CAS procedures for the treatment of extracranial carotid disease in Medicare beneficiaries. A linear-by-linear association was performed to determine the changes of carotid revascularization for the aforementioned period. A total of 23,142 patients received carotid revascularization between 2004 and 2013. CEA was performed in 4,012 and CAS in 19,130 patients. The rate of total carotid revascularization per 1,000,000 Medicare beneficiaries substantially increased during the study period from 22 procedures in 2004 to 57 in 2013 (risk ratio (RR), 2.59; 95% confidence interval (CI), 1.58-4.24; P=0.001). CAS increased from 18 procedures in 2004, to 45 in 2013 (RR, 2.50; 95% CI; 1.45-4.32; P=0.001). In addition, the number of CEA procedures performed per 1,000,000 Medicare beneficiaries increased from four procedures in 2004, to 11 in 2013 (RR, 2.75; 95% CI, 0.88-8.64; P=0.08). In conclusion, total carotid revascularization increased by 255% during the previous 10 years in Korea. This increase predominantly resulted from the 249% increase of CAS. The number and population-based rates of carotid revascularization remained low, as compared with Western countries.

Proteolytic degradation and potential role of onconeural protein cdr2 in neurodegeneration

Cerebellar degeneration-related protein 2 (cdr2) is expressed in the central nervous system, and its ectopic expression in tumor cells of patients with gynecological malignancies elicits immune responses by cdr2-specific autoantibodies and T lymphocytes, leading to neurological symptoms. However, little is known about the regulation and function of cdr2 in neurodegenerative diseases. Because we found that cdr2 is highly expressed in the midbrain, we investigated the role of cdr2 in experimental models of Parkinson's disease (PD). We found that cdr2 levels were significantly reduced after stereotaxic injection of 1-methyl-4-phenylpyridinium (MPP(+)) into the striatum. cdr2 levels were also decreased in the brains of post-mortem PD patients. Using primary cultures of mesencephalic neurons and MN9D cells, we confirmed that MPP(+) reduces cdr2 in tyrosine hydroxylase-positive dopaminergic neuronal cells. The MPP(+)-induced decrease of cdr2 was primarily caused by calpain- and ubiquitin proteasome system-mediated degradation, and cotreatment with pharmacological inhibitors of these enzymes or overexpression of calcium-binding protein rendered cells less vulnerable to MPP(+)-mediated cytotoxicity. Consequently, overexpression of cdr2 rescued cells from MPP(+)-induced cytotoxicity, whereas knockdown of cdr2 accelerated toxicity. Collectively, our findings provide insights into the novel regulatory mechanism and potentially protective role of onconeural protein during dopaminergic neurodegeneration.

Intraoperative indocyanine green angiography for the objective measurement of blood flow

PURPOSE

Intraoperative assessment of tissue perfusion is important to predict wound healing or improvement of symptoms in patients with peripheral arterial disease (PAD) or vascular trauma. There is no widely accepted standard for intraoperative measurement of tissue perfusion. Here, we report the use of indocyanine green (ICG)-based angiography to determine the blood flow in patients with PAD and vascular trauma.

METHODS

The SPY fluorescent imaging system was utilized. A dose of 3-5 mL of ICG (2.5 mg/mL) was injected intravenously followed by a 10 mL normal saline flush. The SPY imaging system was used to quantitatively assess perfusion. During the study period, the SPY imaging system was applied in 4 patients with PAD and one patient with vascular trauma.

RESULTS

In 3 patients with PAD associated with an ischemic wound, complete wound healing was achieved with the indication of viable tissue by the SPY system. In one patient with severe claudication in both lower extremities, the ICG angiography was used to determine the increased blood flow after revascularization. In the case of vascular trauma, this imaging system enabled the delineation of viability of the injured tissue.

CONCLUSION

ICG angiography can determine the surface tissue viability in PAD patients. In cases of severe vascular trauma,the SPY system can be used to determine tissue perfusion. Further study is warranted to define the definite utility of this technology to assess perfusion, response to revascularization, and potentially, to predict the likelihood of wound healing.

Effect of Diameter of Saphenous Vein on Stump Length after Radiofrequency Ablation for Varicose Vein

Purpose:

Radiofrequency ablation (RFA) has gained popularity for treatment of varicose veins. The diameter of the saphenous vein should be considered before RFA because occlusion of the vein may differ depending on its diameter. Until now, however, there have been few data about the correlation between the diameter of the saphenous vein and the stump length after RFA. The purpose of our study was to investigate its correlation.

Materials and Methods:

A retrospective review was performed from prospectively collected data of RFA patients between March 2009 and December 2011. Preoperatively, the saphenous vein diameter was measured. Ablation was initiated 2 cm distal from the junction. Postoperatively, stump length was measured at 1 week and 6 months. After 2 years, we measured the length from the saphenofemoral junction to the leading point of occlusion for great saphenous vein, and length from the saphenopopliteal junction to the leading point of occlusion for small saphenous vein. The paired t-test, independent t-test, and correlation analysis were used for statistical analysis. P-value <0.05 was considered statistically significant.

Results:

During the study period, RFA was performed in 201 patients. Endovenous heat-induced thrombosis developed in 3 patients (1.5%). After 2 years, the stump length was obtained in 74 limbs. The mean diameter and stump length of the saphenous vein were 6.7±1.8 mm and 12.5±8.5 mm, respectively. Correlation analysis showed that the Pearson correlation coefficient of these factors was −0.017.

Conclusion:

There was no correlation between the diameter of saphenous vein and stump length.

National trends for the treatment of peripheral arterial disease in Korea between 2004 and 2013

Purpose

Peripheral arterial disease (PAD) has been a major public health issue in the elderly. Advances in endovascular surgery have led to a substantial shift in the management of PAD. Although the nationwide trend of PAD treatment in the Western countries was reported, limited data have been available on this in Korea. This study examined the national trend in the treatment of PAD in Korea over the past decade.

Methods

Health Insurance Review and Assessment Service data were used. We sought to analyze trends in the open and endovascular surgery for the treatment of PAD in Medicare beneficiaries between 2004 and 2013. We also analyzed trends in each types of surgery in the lower extremity. A linear-by-linear association was performed to determine the changes of PAD treatment for this period.

Results

The rate of open surgery per 100,000 Medicare beneficiaries decreased significantly from 8 procedures in 2004 to 6 in 2013. At the same time, endovascular surgery increased from 23 procedures in 2004 to 59 in 2013. Endovascular surgery in the lower extremity increased more than twofold, while the open surgery decreased by 39%. The rate of balloon angioplasty among endovascular surgery was increased by almost threefold, while the bypass surgery using artificial graft decreased by half.

Conclusion

Endovascular surgery is now performed more commonly than open surgery for PAD treatment. Balloon angioplasty increased by almost threefold, while the bypass surgery using artificial graft decreased by about 50%.

Hypogastric Artery Transposition to Restore the Arterial Flow after Resection of the External Iliac Artery

Tumors in the pelvic cavity frequently involve the iliac vessels. Common and external iliac arteries should be reconstructed to restore the flow to the lower extremity if the tumor directly invades these arteries. We report herein a 58-year-old female patient with a 10×11 cm, recurred uterine leiomyosarcoma. We performed en bloc resection of the tumor mass including the sigmoid colon, left ureter and 5 cm of the left external iliac artery. After complete resection, restoration of arterial flow to the lower extremity was made with a novel strategy of hypogastric artery transposition. There was no evidence of tumor recurrence or vascular insufficiency at 12 months after surgery.

Protective role of quercetin against cisplatin-induced hair cell damage in zebrafish embryos

BACKGROUND AND OBJECTIVES

The aim of this study was to evaluate the protective effects of quercetin on cisplatin-induced hair cell damage in transgenic zebrafish embryos.

MATERIALS AND METHODS

Five days postfertilization zebrafish embryos were exposed to 1 mM cisplatin and quercetin at 10, 50, 100, or 200 μM for 4 h. Hair cells within neuromasts of the supraorbital, otic, and occipital lateral lines were analyzed by fluorescent microscopy (n = 10). Survival of hair cells was calculated as the average number of hair cells in the control group that were not exposed to cisplatin. Ultrastructural changes were evaluated using scanning electron microscopy.

RESULTS

Hair cell damage in neuromasts was decreased by co-treatment of quercetin and cisplatin (quercetin 100 μM: 8.6 ± 1.1 cells; 1 mM cisplatin only: 5.0 ± 0.5 cells; n = 10, p < 0.05); apoptosis of hair cells examined by special stain was also decreased by quercetin. The ultrastructure of hair cells within neuromasts was preserved in zebrafish by the combination of quercetin (100 μM) and cisplatin (1 mM).

CONCLUSION

In conclusion, quercetin showed protective effects against cisplatin-induced toxicity in a zebrafish model. The results of this study suggest the possibility of a protective role of quercetin against cisplatin-induced apoptotic cell death in zebrafish.

Triple shape-memory effect by silanized polyurethane/silane-functionalized graphene oxide nanocomposites bilayer

Graphene oxide (GO) was chemically modified with 3-aminopropyltriethoxysilane (APTES) (f-GO) and incorporated into silanized polyurethanes of two different molecular weights and chemical compositions by sol–gel reactions, and the effects were studied in terms of mechanical, dynamic mechanical, and dual and triple shape-memory polymers (DSMP and TSMP, respectively) of the nanocomposite films. It was found that the f-GO nanoparticles act as multifunctional cross-links as well as reinforcing fillers and significantly augmented the glassy and rubbery state moduli, yield strength, break strength, glass transition temperature, and dual shape-memory properties. A cohesive bilayer of the two films (lower layer and upper layer) fabricated by the interpenetrating polymer network technique exhibited synergistic mechanical properties in the glassy and rubbery states along with two undisturbed glass transitions by which an intermediate plateau region and TSMP were demonstrated.

Measurement of vital sign in chick embryo using multi-channel diffuse speckle contrast analysis

In poultry industry which is avian breeding program, the determination whether chick embryos survive in the artificial incubation periods or not is essential to reduce the financial resources. We developed the multi-channel diffuse speckle contrast analysis (DSCA) system composed of four optical fiber detectors enabling to achieve in-vivo measurements of deep tissue flow noninvasively. The system could confirm vital sign of the chick embryo in early incubation stage. Moreover, it demonstrates the change of relative blood flow index and depth information with simplicity, low cost, and flexibility.

The comparison of monitored anesthesia care with dexmedetomidine and spinal anesthesia during varicose vein surgery

Purpose

The purpose of this study was to investigate the effectiveness and safety of monitored anesthesia care (MAC) using dexmedetomidine for its sedative and analgesic effect during varicose vein surgery.

Methods

Forty-two patients, who underwent varicose vein surgery, were divided into the MAC group (n = 20) or the spinal anesthesia group (n = 22) for randomized clinical trial. In the MAC group, dexmedetomidine was administered by a loading dose of 1 µg/kg for 10 minutes, followed by a maintenance infusion of 0.2-1.0 µg/kg/hr. Ketamine was used for intermittent injection. In the spinal anesthesia group, midazolam was used for sedation. Intraoperative vital signs, the number of adverse events, and the satisfaction of patients and surgeons concerning the anesthetic condition were compared between the two groups.

Results

Systolic blood pressure was intraoperatively significantly different over time between the two groups. The groups had statistical differences in the change in heart rate with regard to time. In the postanesthetic care unit, patients and surgeons in the MAC group had a lower satisfaction score, compared to patients and surgeons in the spinal anesthesia group. However, in the recovery period, patients had a positive perception concerning MAC anesthesia. In addition, without significant adverse events, the MAC group had a shorter time to possible ambulation, which indicated an early recovery.

Conclusion

We believe that MAC using dexmedetomidine in combination with ketamine may be an alternative anesthetic technique for varicose vein surgery with regard to a patient's preference and medical condition.

Reconstruction of the internal iliac artery in patients with aneurysmal disease: Two case reports

During the endovascular repair of aortoiliac aneurysm, bilateral internal iliac artery (IIA) occlusion may give rise to significant morbidities such as ischemia of buttock or sigmoid colon and erectile dysfunction. Open and endovascular approaches are used to maintain IIA circulation in such cases. The present report describes the cases of two patients who underwent external-to-internal iliac artery bypass surgery, one via a novel hybrid approach. The first patient had a right common iliac artery aneurysm without a sufficient distal landing zone for endovascular repair. The distal landing of the device was therefore placed in the right external iliac artery (EIA). The tortuous portion of the right EIA was excised and anastomosed in an end-to-end fashion. An external-to-internal iliac artery bypass was then performed. The second patient underwent endovascular repair of the IIA aneurysm with a Gore^® Viabahn^®-covered stent (W. L. Gore and Associates, Inc., Flagstaff, AZ, USA). This covered stent was anastomosed with the iliac bypass graft. Postoperative pelvic circulation was maintained. In conclusion, this strategy for maintaining IIA flow is a potential novel approach for future use.

The cutoff value of saphenous vein diameter to predict reflux

Purpose

Increased saphenous vein diameter is a common consequence of saphenous vein reflux. Until now, there have been no reports about the correlation between diameter and reflux of saphenous vein in Korea. The aim of this study was to investigate the correlation between saphenous vein reflux and diameter changes.

Methods

From April 2009 to August 2012, 777 patients were sent to the vascular laboratory for evaluation of venous reflux. The diameter of the saphenous vein was measured with B-mode imaging, and reflux was quantified based on valve closure time using Doppler spectral tracings. Receiver operating characteristics curve analysis was applied to determine the best saphenous vein diameter cutoff for predicting reflux.

Results

The mean diameters of normal great saphenous vein (GSV) and refluxed GSV were 5.0 ± 2.4 mm and 6.4 ± 2.0 mm, respectively. The mean diameters of normal small saphenous vein (SSV) and refluxed SSV were 3.1 ± 1.3 mm and 5.2 ± 2.7 mm, respectively. The diameter differences between the normal and refluxed GSV and SSV were 1.4 mm and 2.1 mm, respectively, and these differences were statistically significant (P < 0.0001). A GSV threshold diameter of 5.05 mm had the best positive predictive value for reflux. The sensitivity and specificity at 5.05 mm were 76% and 60%, respectively. The best SSV diameter for predicting reflux was 3.55 mm. The sensitivity and specificity at 3.55 mm were 87% and 71%, respectively.

Conclusion

GSV diameter of ≥5.05 mm had the best positive predictive value for pathologic reflux. For pathologic reflux of SSV, the best cutoff diameter was 3.55 mm.

Simultaneous hybrid revascularization for symptomatic lower extremity arterial occlusive disease

Multilevel revascularization, using a combination of endovascular and open (hybrid) surgery, is increasingly being used. Hybrid surgery allows complex anatomy to be treated by minimally invasive procedures in medically high risk patients. The aim of the present study was to report a novel hybrid surgery for lesions in the multilevel lower extremity arteries and to evaluate the clinical outcomes. Consecutive patients who presented at a single institution between March 2009 and Feburary 2012 were selected for inclusion in the study. The patients had disabling claudication or critical limb ischemia and underwent treatment for revascularization by open surgery or by a combination of open surgery and endovascular procedure. Retrospective analysis was conducted from a prospectively collected database. All procedures were performed by a vascular surgeon in an operating room. Postoperative surveillance in outpatient clinics was conducted at 3 and 6 months and every 6 months thereafter. A total of 76 patients were included in the study with a mean age of 67.1±11.3 years (range, 42-94 years) and the male to female ratio was 67:9. The most common indication for revascularization was Rutherford category IV (resting pain). The immediate technical success rate of hybrid surgery was 90.5%, with an overall limb salvage rate of 97.4%. The primary patency rates of the hybrid and open groups were 100 and 90.9%, respectively (P=0.441). Therefore, the results of the present study indicate that hybrid surgery is a feasible option for the treatment of multilevel peripheral arterial occlusive disease, showing favorable patency and limb salvage rates. These observations indicate that femoral endarterectomy plays a vital role in hybrid surgery.

Predictive factors for gastroduodenal toxicity based on endoscopy following radiotherapy in patients with hepatocellular carcinoma

PURPOSE

The aim of this work was to determine predictive factors for gastroduodenal (GD) toxicity in hepatocellular carcinoma (HCC) patients who were treated with radiotherapy (RT).

PATIENTS AND METHODS

A total of 90 HCC patients who underwent esophagogastroduodenoscopy (EGD) before and after RT were enrolled. RT was delivered as 30-50 Gy (median 37.5 Gy) in 2-5 Gy (median 3.5 Gy) per fraction. All endoscopic findings were reviewed and GD toxicities related to RT were graded by the Common Toxicity Criteria for Adverse Events, version 3.0. The predictive factors for the ≥ grade 2 GD toxicity were investigated.

RESULTS

Endoscopic findings showed erosive gastritis in 14 patients (16 %), gastric ulcers in 8 patients (9 %), erosive duodenitis in 15 patients (17 %), and duodenal ulcers in 14 patients (16 %). Grade 2 toxicity developed in 19 patients (21 %) and grade 3 toxicity developed in 8 patients (9 %). V25 for stomach and V35 for duodenum (volume receiving a RT dose of more than x Gy) were the most predictive factors for ≥ grade 2 toxicity. The gastric toxicity rate at 6 months was 2.9 % for V25 ≤ 6.3 % and 57.1 % for V25 > 6.3 %. The duodenal toxicity rate at 6 months was 9.4 % for V35 ≤ 5.4 % and 45.9 % for V35 > 5.4 %. By multivariate analysis including the clinical factors, V25 for stomach and V35 for duodenum were the significant factors.

CONCLUSION

EGD revealed that GD toxicity is common following RT for HCC. V25 for the stomach and V35 for the duodenum were the significant factors to predict ≥ grade 2 GD toxicity.

Endovascular abdominal aortic aneurysm repair in patients with renal transplant

The repair of abdominal aortic aneurysm (AAA) in patients with functioning renal transplant is critical because it is important to avoid ischemic and reperfusion injury to the transplanted kidney. Endovascular aneurysm repair (EVAR) avoids aortic cross clamping and can prevent renal graft ischemia. Here we report the endovascular management and outcome of AAA in two renal transplant patients using a bifurcated aortic stent graft. One patient underwent EVAR using a small amount of contrast (30 mL) due to decreased renal function resulting from chronic rejection. Another patient had EVAR performed with iliac conduit because of the heavily calcified, stenotic lesion of external iliac artery. EVAR in patients with a renal transplant is a feasible option without impairing renal arterial flow.

Evaluation of anatomical landmark position differences between respiration-gated MRI and four-dimensional CT for radiation therapy in patients with hepatocellular carcinoma

OBJECTIVE

To measure the accuracy of position differences in anatomical landmarks in gated MRI and four-dimensional CT (4D-CT) fusion planning for radiation therapy in patients with hepatocellular carcinoma (HCC).

METHODS

From April to December 2009, gated MR and planning 4D-CT images were obtained from 53 inoperable HCC patients accrued to this study. Gated MRI and planning 4D-CT were conducted on the same day. Manual image fusions were performed by matching the vertebral bodies. Liver volumes and three specific anatomical landmarks (portal vein conjunction, superior mesenteric artery bifurcation, and other noticeable points) were contoured from each modality. The points chosen nearest the centre of the four landmark points were compared to measure the accuracy of fusion.

RESULTS

The average distance differences (±standard deviation) of four validation points were 5.1 mm (±4.6 mm), 5.6 mm (±6.2 mm), 5.4 mm (±4.5 mm) and 5.1 mm (±4.8 mm). Patients who had ascites or pulmonary disease showed larger discrepancies. MRI-CT fusion discrepancy was significantly correlated with positive radiation response (p<0.05).

CONCLUSIONS

Approximately 5-mm anatomical landmark positional differences in all directions were found between gated MRI and 4D-CT fusion planning for HCC patients; the gap was larger in patients with ascites or pulmonary disease.

ADVANCES IN KNOWLEDGE

There were discrepancies of approximately 5 mm in gated MRI-CT fusion planning for HCC patients.

The occlusion rate and patterns of saphenous vein after radiofrequency ablation

Purpose

Radiofrequency ablation (RFA) is a widely accepted to treat the varicose vein. However, outcome studies for occlusion rate and patterns of the saphenous vein after RFA are scarce. The purpose of our study is to report the results of RFA in patients with varicose vein.

Methods

We retrospectively reviewed the clinical outcomes after RFA using ClosureFAST (Covidien) catheter. We evaluated the occlusion rate and patterns with duplex scanning after RFA.

Results

A total of 200 limbs (148 patients) underwent RFA. The truncal veins were ablated in 163 great saphenous veins (GSV) and 41 small saphenous veins (SSVs). The mean age was 52.1 ± 11.9 years and female to male ratio was 125 : 87. At the mean follow-up of 13.9 months, the CEAP score, VCSS, and QoL score were significantly improved 2.33 ± 0.78 to 1.29 ± 0.96 (P < 0.0001), 3.48 ± 0.98 to 0.63 ± 1.16 (P < 0.0001), and 6.91 ± 6.69 to 3.38 ± 4.74 (P < 0.0001), respectively. The occlusion rate was 94.6% (53/56) in GSV and 94.5% (17/18) in SSV. The most common occlusion pattern in GSV was total occlusion of main trunk with patent superficial inferior epigastric vein in 41.1%. And, the most common pattern in SSV was the total occlusion of SSV with stump in 66.7%.

Conclusion

RFA is an effective modality in the treatment of varicose vein. At the mean follow-up of 13.9 months, the occlusion rate was 94.6%in GSV and 94.5% in SSV. There are several patterns of saphenous occlusion after RFA.

Reference diameters of the abdominal aorta and iliac arteries in the Korean population

PURPOSE

It is important to know the normal diameter of artery throughout the body so that clinicians are able to determine when an artery becomes aneurysmal. However, there are no previous studies on the normal diameter of arteries in the general Korean population. The purpose of this article is to determine the normal reference diameters of the abdominal aorta and iliac arteries in the Korean population.

MATERIALS AND METHODS

We recruited the study population from three cities in Korea for the abdominal aortic aneurysm (AAA) screening. We measured the diameter of the aorta and iliac arteries. We analyzed the reference diameter of the population without AAA. The results were analyzed by Student's t-test and ANOVA on SPSS version 19. A p value <0.05 was considered to be statistically significant.

RESULTS

One thousand two hundred and twenty-nine people were enrolled. 478 men and 751 women, with a mean age of 63.9 ± 10.1 years (range 50 to 91) were examined. Eleven out of 1229 (0.89%) were diagnosed with AAA. In the population of 1218 people without AAA, the mean diameters (cm) of male/female were 2.20/2.11 (p<0.001) at suprarenal, 2.04/1.90 (p<0.001) at renal, 1.90/1.79 (p<0.001) at infrarenal, 1.22/1.17 (p<0.001) at right iliac and 1.47/1.15 (p=0.097) at the left iliac, respectively. There was a significantly larger diameter in the male population. The diameter of each level increased with age.

CONCLUSION

The normal reference diameter of the infrarenal abdominal aorta in the Korean population is 1.9 cm in males and 1.79 cm in females. The diameter of the abdominal aorta increases with age.

Volumetric response evaluation after intensity modulated radiotherapy in patients with supratentorial gliomas

Radiotherapy is frequently indicated to treat cerebral gliomas. Accurate response evaluation after radiotherapy is essential to determine the efficacy of treatment. We retrospectively analyzed the volumetric tumor response after simultaneous integrated boost-intensity modulated radiotherapy (SIB-IMRT) in patients with gliomas. Thirty-five patients (Grade II, 7 patients; Grade III, 12; and Grade IV, 16) were treated with SIB-IMRT with a median total dose of 55.9 Gy/26 fractions for Grade II and 60 Gy/25 fractions for Grade III-IV tumors. Tumor responses were evaluated for enhancing volume on post-gadolinium T1-weighted images (Vgd) and hyper-intensity volume on T2-weighted FLAIR images (V(fl)) on serial MRIs. With the median follow-up of 24.0 months, overall response rates (RRs) were 57% for V(gd) and 51% for V(fl). Tumor grade was predictive of response favoring the lower grade in Vfl with RRs of 86% for Grade II, 75% for Grade III, and 19% for Grade IV tumors (p = 0.004). Time to 50% or greater volume reduction (T50) in Vgd was 8 months for grade III. The T50 in V(fl) was approximately 24 months both for Grade II and III tumors. Majority of Grade IV tumors continued to progress and never reached the T50 in Vgd or Vfl. Responders survived longer than non-responders for V(gd) and V(fl). Volume response after radiotherapy was dependent upon tumor grade and time. LGGs are very responsive to radiotherapy with the RRs of 86% in V(fl). The response of Vfl is more protracted compared to V(gd). Further investigation is needed to determine the clinical significance of volumetric response evaluation.

Clinical manifestations of hypercalcemia and hypophosphatemia after kidney transplantation

INTRODUCTION

Abnormalities of calcium and phosphorus metabolism in end-stage renal disease patients can persist after transplantation. We investigated their natural courses after transplantation, their risk factors for posttransplantation hypercalcemia and hypophosphatemia, and their impacts on allograft outcomes.

METHODS

We retrospectively analyzed a total of 490 adult patients who underwent kidney transplantations between 2000 and 2009.

RESULTS

The serum calcium continued to increase, and reaching a plateau at around 3 months after transplantation. Thereafter it decreased, reaching a stable level by 2 years. Forty-four patients (9.0%) displayed hypercalcemia within 1 year; it persisted longer than that in 23 subjects (4.7%). Both longer dialysis duration (odds ratio [OR] 1.423; 95% confidence interval [CI], 1.192-1.699) and high intact serum parathyroid hormone (iPTH) level before transplantation (OR 1.002; 95% CI, 1.000-1.003) increased the risk for posttransplantation hypercalcemia. After a significant decrease during the first week, the serum phosphorus level increased, becoming stable between 1 and 6 months after transplantation. Hypophsphatemia occurred in 379 patients (77.3%) with 336 patients displaying hypophosphatemia without hypercalcemia. However, neither hypercalcemia nor hypophosphatemia influenced graft outcomes. Eight patients underwent pretransplantation parathyroidectomy, whereas 4 patients underwent posttransplantation parathyroidectomy. Neither group of patients experienced posttransplantation hypercalcemia.

CONCLUSIONS

Both hypercalcemia and hypophosphatemia are common after renal transplantation, especially among patients with a long history of dialysis before transplantation. Strict control of hyperparathyroidism including parathyroidectomy before transplantation may be the appropriate approach to these abnormalities.

Anisotropy and non-homogeneity of an Allomyrina Dichotoma beetle hind wing membrane

Biomimetics is one of the most important paradigms as researchers seek to invent better engineering designs over human history. However, the observation of insect flight is a relatively recent work. Several researchers have tried to address the aerodynamic performance of flapping creatures and other natural properties of insects, although there are still many unsolved questions. In this study, we try to answer the questions related to the mechanical properties of a beetle's hind wing, which consists of a stiff vein structure and a flexible membrane. The membrane of a beetle's hind wing is small and flexible to the point that conventional methods cannot adequately quantify the material properties. The digital image correlation method, a non-contact displacement measurement method, is used along with a specially designed mini-tensile testing system. To reduce the end effects, we developed an experimental method that can deal with specimens with as high an aspect ratio as possible. Young's modulus varies over the area in the wing and ranges from 2.97 to 4.5 GPa in the chordwise direction and from 1.63 to 2.24 GPa in the spanwise direction. Furthermore, Poisson's ratio in the chordwise direction is 0.63-0.73 and approximately twice as large as that in the spanwise direction (0.33-0.39). From these results, we can conclude that the membrane of a beetle's hind wing is an anisotropic and non-homogeneous material. Our results will provide a better understanding of the flapping mechanism through the formulation of a fluid-structure interaction analysis or aero-elasticity analysis and meritorious data for biomaterial properties database as well as a creative design concept for a micro aerial flapper that mimics an insect.

A modified blade element theory for estimation of forces generated by a beetle-mimicking flapping wing system

We present an unsteady blade element theory (BET) model to estimate the aerodynamic forces produced by a freely flying beetle and a beetle-mimicking flapping wing system. Added mass and rotational forces are included to accommodate the unsteady force. In addition to the aerodynamic forces needed to accurately estimate the time history of the forces, the inertial forces of the wings are also calculated. All of the force components are considered based on the full three-dimensional (3D) motion of the wing. The result obtained by the present BET model is validated with the data which were presented in a reference paper. The difference between the averages of the estimated forces (lift and drag) and the measured forces in the reference is about 5.7%. The BET model is also used to estimate the force produced by a freely flying beetle and a beetle-mimicking flapping wing system. The wing kinematics used in the BET calculation of a real beetle and the flapping wing system are captured using high-speed cameras. The results show that the average estimated vertical force of the beetle is reasonably close to the weight of the beetle, and the average estimated thrust of the beetle-mimicking flapping wing system is in good agreement with the measured value. Our results show that the unsteady lift and drag coefficients measured by Dickinson et al are still useful for relatively higher Reynolds number cases, and the proposed BET can be a good way to estimate the force produced by a flapping wing system.

Correlations of trained panel sensory values of cooked pork with fatty acid composition, muscle fiber type, and pork quality characteristics in Berkshire pigs

The objective was to examine the relationship of trained panel sensory scores of cooked pork with fatty acid composition, muscle fiber type, and meat quality characteristics from Berkshire pigs. No or few associations were found between the panel sensory scores of cooked meat, especially tenderness attributes, and fatty acid composition; however, intramuscular fat content positively correlated with off-flavor score (r=0.31). On the other hand, the morphological characteristics of muscle fibers were correlated with panel sensory values. Muscles with smaller cross-sectional area and higher density of fibers were more closely associated with softer, more tender panel scores and a lower number of chews than muscles with larger fiber area and lower density of fibers. The water holding capacity test of filter-paper fluid uptake was moderately correlated with panel scores of softness (r=0.33), initial tenderness (r=0.38), chewiness (r=0.40), juiciness (r=-0.27), flavor intensity (r=-0.23), and off-flavor (r=0.30). Panel sensory values of Berkshire pig meat was moderately related to postmortem meat quality, especially water holding capacity. A more thorough understanding of the relationships between fatty acid composition and muscle fiber type with palatability is needed.