The Feasibility of Fast, Four-Dimensional Computed Tomography-Based O-Ring Linac Plans for Stereotactic Body Radiotherapy in Patients with Poor Performance Status

PURPOSE/OBJECTIVE(S)

As patients with poor performance status cannot endure long treatment times, it can lead to unplanned and prolonged radiation treatment or discontinuation of treatment. Moreover, prolonged radiation treatment appears to negatively affect survival for patients. We aimed to verify the feasibility of fast 4DCT-based O-ring linear accelerator (LINAC) treatment in lung 4D stereotactic body radiotherapy (SBRT).

MATERIALS/METHODS

This study included data of 38 patients who received lung 4D-SBRT. Gating20-70% plans were based on 4DCT data obtained at phase values ranging from 20-70% using a C-arm LINAC. Non-GatingFB plans were retrospectively established based on 4DCT data obtained at phase values of 0-90% using an O-ring LINAC. The prescribed dose of 4,800 cGy was delivered to PTV in four fractions. The conformity index (CI), homogeneity index (HI), and gradient measurement (GM) of the PTV were analyzed to compare dosimetric data between Gating20-70% and Non-GatingFB plans. Organs at risks (OARs) were analyzed in accordance with the RTOG 0915 protocol. Treatment delivery time and total monitor units (MU) were analyzed to compare the efficiency of treatment delivery. Statistical comparisons were performed using the Wilcoxon signed-rank test (p<0.05).

RESULTS

For the PTV, there was no significant difference in the CI or HI between Gating20-70% and Non-GatingFB plans (CI: 1.337±0.137, 1.335±0.174, HI: 0.939±0.015, 0.939±0.016, all at p>0.05). However, there was a significant difference in GM between Gating20-70% and Non-GatingFB plan (1.528±0.206 cm, 1.381±0.222 cm, p<0.001). For OARs, all plans met the criteria for dose constraint. There was a significant difference between Gating20-70% and Non-GatingFB plans except in the spinal cord. In particular, D1000cc and D1500cc values for the ipsilateral lung for Gating20-70% plans were 31.6% and 59.9% lower than those for Non-GatingFB plans (D1000cc: 50.780±132.061 cGy, 34.755±102.480 cGy, p<0.001, D1500cc: 6.641±14.598 cGy, 2.666±7.926 cGy, p<0.001). Treatment delivery time was 92% longer for Gating20-70% plans than for Non-GatingFB plans (5.0±0.4 min, 9.6±3.3 min, p = 0.043). The total MU value for Gating20-70% plans was 9.6% higher than that for Non-GatingFB plans (3665.8±230.7, 4016±236.9, p = 0.039).

CONCLUSION

When compared to OARs both plans were acceptable per RTOG-0915 protocol, but significant differences were between Non-GatingFB and Gating20-70% plans. However, treatment delivery time of Non-GatingFB plans decreased by 47.9% than Gating20-70% plans. We verified the feasibility of fast 4DCT-based O-ring LINAC treatment for patients who cannot endure long treatment times due to poor performance status in lung 4D-SBRT. In further study, we will analyze dosimetric differences and treatment delivery efficiency considering tumor motion according to tumor location.

Liquid-like properties of cyclopentadienyl complexes of barium: molecular dynamics simulations of nanoscale droplets

Cyclopentadienyl complexes of barium have great utility in materials science and engineering, in particular, as precursors in the atomic layer deposition processes, which are required to be fluidic as well as thermally stable and volatile. Here, we investigated the liquid-like properties of cyclopentadienyl barium complexes including (Me₅C₅)₂Ba, (^tBu₃C₅H₂)₂Ba, (ⁱPr₄C₅H)₂Ba, (ⁱPr₅C₅)₂Ba, and [(SiMe₃)₃C₅H₂]₂Ba, using molecular dynamics simulations of nanoscale droplets. The compounds were modeled using a recently developed generic force field, GFN-FF. Nanoscale droplets with about 5.0 nm diameters were formed by aggregating 96 molecules of each compound. Simulation results reveal that substituting methyl groups of (Me₅C₅)₂Ba with other alkyl and silyl moieties has a non-negligible effect on the intra- and intermolecular structure and dynamics. In particular, in contrast to more flexible (Me₅C₅)₂Ba, the substitution with five iso-propyl groups to form (ⁱPr₅C₅)₂Ba adds rigidity to the complex with restricted orientational fluctuations for two cyclopentadienyl ligands and arranges molecules parallel to each other with greater probability. In addition, comparison between (^tBu₃C₅H₂)₂Ba, with three tert-butyl groups, and its silyl analogue, [(SiMe₃)₃C₅H₂]₂Ba, reveals that intermolecular interactions between the molecules with silyl groups are softer than those with tert-butyl groups and result in broader radial distribution functions, whereas the dynamic properties are similar for both compounds. This work suggests that molecular dynamics simulations contribute to molecular-level understanding of the effect of chemical substitution in organometallic compounds on the intra- and intermolecular properties of molecular liquids.

Longitudinal analysis of symptom-based clustering in patients with primary Sjogren's syndrome: a prospective cohort study with a 5-year follow-up period

BACKGROUND

Sjogren's syndrome (SS) is a heterogenous disease with various phenotypes. We aimed to provide a relevant subclassification based on symptom-based clustering for patients with primary (p) SS.

METHODS

Data from patients in a prospective pSS cohort in Korea were analysed. Latent class analysis (LCA) was performed using patient reported outcomes, including pain, fatigue, dryness, and anxiety/depression. Clinical and laboratory differences between the classes were analysed. Latent transition analysis (LTA) was applied to the longitudinal data (annually for up to 5 years) to assess temporal stability of the classifications.

RESULTS

LCA identified three classes among 341 patients with pSS (i.e., 'high symptom burden', 'dryness dominant', 'low symptom burden'). Each group had distinct laboratory and clinical phenotypes. LTA revealed that class membership remained stable over time. Baseline class predicted future salivary gland function and damage accrual represented by a Sjogren's syndrome disease damage index.

CONCLUSION

Symptom-based clustering of heterogenous patients with primary Sjogren's syndrome provided a relevant classification supported by temporal stability over time and distinct phenotypes between the classes. This clustering strategy may provide more homogenous groups of pSS patients for novel treatment development and predict future phenotypic evolvement.

Ribosomal protein S3 associates with the TFIIH complex and positively regulates nucleotide excision repair

In mammalian cells, the bulky DNA adducts caused by ultraviolet radiation are mainly repaired via the nucleotide excision repair (NER) pathway; some defects in this pathway lead to a genetic disorder known as xeroderma pigmentosum (XP). Ribosomal protein S3 (rpS3), a constituent of the 40S ribosomal subunit, is a multi-functional protein with various extra-ribosomal functions, including a role in the cellular stress response and DNA repair-related activities. We report that rpS3 associates with transcription factor IIH (TFIIH) via an interaction with the xeroderma pigmentosum complementation group D (XPD) protein and complements its function in the NER pathway. For optimal repair of UV-induced duplex DNA lesions, the strong helicase activity of the TFIIH complex is required for unwinding damaged DNA around the lesion. Here, we show that XP-D cells overexpressing rpS3 showed markedly increased resistance to UV radiation through XPD and rpS3 interaction. Additionally, the knockdown of rpS3 caused reduced NER efficiency in HeLa cells and the overexpression of rpS3 partially restored helicase activity of the TFIIH complex of XP-D cells in vitro. We also present data suggesting that rpS3 is involved in post-excision processing in NER, assisting TFIIH in expediting the repair process by increasing its turnover rate when DNA is damaged. We propose that rpS3 is an accessory protein of the NER pathway and its recruitment to the repair machinery augments repair efficiency upon UV damage by enhancing XPD helicase function and increasing its turnover rate.

Inhibition of Photoconversion Activity in Self-Assembled ZnO-Graphene Quantum Dots Aggregated by 4-Aminophenol Used as a Linker

The aggregation of zinc oxide nanoparticles leads to an increased absorbance in the ultraviolet-visible region by an induced light scattering effect. Herein, we demonstrate the inhibition of photoconversion activity in ZnO-graphene core-shell quantum dots (QD) (ZGQDs) agglomerated by 4-aminophenol (4-AP) used as a linker. The ZnO-graphene quantum dots (QD) aggregates (ZGAs) were synthesized using a facile solvothermal process. The ZGAs revealed an increased absorbance in the wavelengths between 350 and 750 nm as compared with the ZGQDs. Against expectation, the calculated average photoluminescence lifetime of ZGAs was 7.37 ns, which was 4.65 ns longer than that of ZGQDs and was mainly due to the high contribution of a slow (τ2, τ3) component by trapped carriers in the functional groups of graphene shells and 4-AP. The photoelectrochemical (PEC) cells and photodetectors (PDs) were fabricated to investigate the influence of ZGAs on the photoconversion activity. The photocurrent density of PEC cells with ZGAs was obtained as 0.04 mA/cm2 at 0.6 V, which was approximately 3.25 times lower than that of the ZGQDs. The rate constant value of the photodegradation value of rhodamine B was also decreased by around 1.4 times. Furthermore, the photoresponsivity of the PDs with ZGAs (1.54 μA·mW-1) was about 2.5 times as low as that of the PDs with ZGQDs (3.85 μA·mW-1). Consequently, it suggests that the device performances could be degraded by the inhibition phenomenon of the photoconversion activity in the ZGAs due to an increase of trap sites.

Low free T3 to free T4 ratio was associated with low muscle mass and impaired physical performance in community-dwelling aged population

In aged population, the association of thyroid hormones on physical performance, especially within their normal range, has yet to be elucidated. In this study, individuals with low serum free T3/free T4 were likely to have low muscle mass and impaired physical performance.

PURPOSE

We aimed to evaluate the associations of muscle mass, strength, and physical performance with thyroid hormone in an aged euthyroid population from a community-based cohort.

METHODS

We examined 918 men aged over 60 years and 1215 postmenopausal women from the Ansung cohort study. Appendicular skeletal muscle mass divided by square of height (ASM/ht²) was used as the muscle mass index. Hand grip strength was measured using a hydraulic dynamometer. Physical performance was assessed using the short physical performance battery (SPPB).

RESULTS

Participants with higher tertiles of free T3 and free T3/free T4 were younger and had higher ASM/ht², stronger hand grip strength, and higher SPPB scores than those in the lower tertiles. In adjusted models, men within higher tertiles of free T3 had higher ASM/ht² compared with those within lower tertiles (p = 0.033), whereas subjects with higher tertiles of free T4 had lower ASM/ht² compared with those within lower tertiles (p = 0.043). Subjects within higher tertiles of free T3/free T4 had higher ASM/ht² (p < 0.001) and better physical performance (p = 0.048) than those within lower tertiles after adjustments. However, free T3, free T4, or free T3/free T4 was not related to hand grip strength after adjustment for covariates.

CONCLUSION

Our results thus indicate that in an aged euthyroid population, low serum free T3/free T4 was a better index for low muscle mass and impaired physical performance than serum free T3 or free T4 alone.

P3617Systolic blood pressure, glycemic control and clinical outcome in diabetic patients with acute myocardial infarction

Background

Recent blood pressure guidelines recommend intensive blood pressure control in diabetic patients with cardiovascular disease.

Purpose

We sought to investigate combined impact of intensive blood glucose lowering and blood pressure control on clinical outcome in diabetic patients with acute myocardial infarction (AMI) has not been fully investigated yet.

Method

Korean Acute Myocardial Infarction Registry (KAMIR) – National Institute of Health (NIH) database included 12,179 patients (9,046 men; mean age = 63.6±12.6 year-old) who were discharged alive. Among them, 3,430 (28.2%) had a diabetes mellitus (DM). MACCEs were defined as a composition of all cause death, non-fatal MI, repeat revascularizations including repeated percutaneous coronary intervention and coronary bypass grafting, cerebrovascular accident and rehospitalizations at 1 year. This research was supported by a fund by Research of Korea Centers for Disease Control and Prevention.

Result

We determined cut-off value of discharge systolic blood pressure (SBP) to predict 1-year MACCE in DM and non-DM patients. Discharge SBP of less than 130mmHg was associated with a lower MACCE at 1 year compared to SBP level of 130mmHg or greater (10.8% versus 15.4%; log-rank p=0.001) in DM patients, whereas discharge SBP cut-off level was 140mmHg to discriminate 1-year MACCE in non-DM patients (6.4% versus 8.5%, log-rank p=0.045). In DM patients, there were no significant difference in 1-year MACCEs between patients with HbA1c less than 7% versus 7% or greater (12.0% versus 10.7%; log-rank p=0.325). DM patients were categorized into 4 groups; discharge SBP <130mmHg and HbA1c <7% (Group 1); discharge SBP <130mmHg and HbA1c ≥7% (Group 2); discharge SBP ≥130mmHg and HbA1c <7% (Group 3); discharge SBP ≥130mmHg and HbA1c ≥7% (Group 4). Intensive BP control was associated lower 1-year MACCEs in patients with good glycemic control (Group 1 & 3; 10.7% versus 16.7%; log-rank p=0.009). However, in patients with poor glycemic control, intensive BP control did not improve 1-year MACCEs (Group 2 & 4; 10.6% versus 11.1%; log-rank p=0.761).

Conclusion

Strict BP control is more important than glycemic control to improve short-term clinical outcome in DM patients with AMI. However, in patients with poor glycemic control, strict BP control did not improve clinical outcome.

P3583Optimal procedural strategy to improve clinical outcome in primary percutaneous coronary intervention

Background

Current guideline recommends potent antiplatelet agents and transradial intervention. However, it is uncertain whether routine use of IVUS, thrombus aspiration and glycoprotein IIB-IIIA inhibitor is beneficial for improving clinical outcome in patients with ST-segment elevation myocardial infarction (STEMI).

Purpose

The aim of this study was to investigate optimal procedural strategy to improve clinical outcome.

Methods

A total of 6,046 patients who underwent primary percutaneous coronary intervention (PCI) for STEMI were analyzed from the Korean Acute Myocardial Infarction Registry (KAMIR) – National Institute of Health (NIH) database. MACCEs were defined as a composition of all cause death, non-fatal MI, repeat revascularizations including repeated percutaneous coronary intervention and coronary bypass grafting, cerebrovascular accident and rehospitalizations. This research was supported by a fund by Research of Korea Centers for Disease Control and Prevention.

Results

During the primary PCI, potent antiplatelet agents such as prasugrel and ticagrelor were used in 2342 (38.4%). PCI was performed through transradial approach in 1490 (25.2%). Thrombus aspiration and intravascular ultrasound (IVUS) examination was done in 2204 (36.1%) and 1079 (18.1%), respectively. Glycoprotein IIB-IIIA inhibitor was administered in 1295 (21.7%). Among them, potent antiplatelet agents, transradial intervention, IVUS, and thrombus aspiration significantly reduced MACCEs at 1 year. Glycoprotein IIB-IIIA inhibitor was not effective to improved clinical outcome. In Cox-proportional hazards model, potent antiplatelet agents (hazard ratio 0.82, 95% confidence interval 0.67–0.99; p=0.045) and transradial intervention (hazard ratio 0.61, 95% confidence interval 0.47–0.78; p<0.001) was an independent predictor of MACCEs after adjusting for confounding variables. Combined use of potent antiplatelet agents and transradial intervention (hazard ratio 0.54; 95% confidence interval 0.37–0.80; p=0.002) substantially reduced MACCEs at 1 year.

Conclusion

Among evidence based procedures during the primary PCI, combined use of potent antiplatelet agents and transradial intervention was optimal procedural strategy to improve clinical outcome.

Effect of Human Corneal Mesenchymal Stromal Cell-derived Exosomes on Corneal Epithelial Wound Healing

Purpose

Mesenchymal stromal cells (MSCs) have been used therapeutically to modulate inflammation and promote repair. Extracellular vesicles, including exosomes, have been identified as one of the important mediators. This study investigated the effect of human corneal MSC-derived exosomes on corneal epithelial wound healing.

Methods

Corneal MSCs (cMSCs) were isolated from human cadaver corneas. The secretome was collected after 72 hours and exosomes were isolated using differential ultracentrifugation. Morphology and size of exosomes were examined by electron microscopy and dynamic light scattering. Expression of CD9, CD63, and CD81 by cMSC exosomes was evaluated by western blotting. Cellular uptake of exosomes was studied using calcein-stained exosomes. The effect of exosome on wound healing was measured in vitro using a scratch assay and in vivo after 2-mm epithelial debridement wounds in mice.

Results

cMSC exosomes were morphologically round and main population ranged between 40 and 100 nm in diameter. They expressed CD9, CD63, and CD81, and did not express GM130, Calnexin, and Cytochrome-C. Stained cMSC exosomes were successfully taken up by human cMSCs, human corneal epithelial cells (HCECs), and human macrophages in vitro and by corneal epithelium in vivo. In scratch assay, after 16 hours, cMSC exosome treated HCECs had 30.1% ± 14% remaining wound area compared to 72.9% ± 8% in control (P < 0.005). In vivo, after 72 hours, cMSC exosome-treated corneas had 77.5% ± 3% corneal wound healing compared to 41.6% ± 7% in the control group (P < 0.05).

Conclusions

Human cMSC exosomes can accelerate corneal epithelial wound healing, and thus, may provide a therapeutic approach for ocular surface injuries.

Characteristics of heart rate variability in women with polycystic ovary syndrome: A retrospective cross-sectional study

We aimed to compare the modulation of the autonomic nervous system (ANS) in women with polycystic ovary syndrome (PCOS) with that in healthy ovulatory women on the basis of heart rate variability (HRV), and to analyze the characteristics of the ANS in PCOS.In a retrospective chart review, HRV, body mass index, and physical examination data in women with PCOS and those with regular menstrual cycles were collected. Approval from the institutional review board (IRB) was obtained (IRB No. 2017-05-007-001) for this study. The mean outcomes were the values of HRV in the time [standard deviation of all normal R-R intervals (SDNN), the square root of the sum of the squares of the differences between the adjacent normal R-R intervals (rMSSD), and the mean heart rate turbulence (mean HRT)] and frequency [total power (TP), very-low-frequency power (VLF), low-frequency power (LF), normalized low-frequency power (LF norm), high-frequency power (HF), normalized high-frequency power (HF norm), and LF/HF ratio] domains. Differences between the 2 groups were analyzed by Mann-Whitney U test, using SPSS for Windows (version 22.0).There was no significant difference in the values of the time domain (SDNN, rMSSD, and mean HRT) between the groups. In the frequency domain, women with PCOS showed significantly higher LF (598.63 ± 94.38 vs 459.13 ± 163.64, P = .028), LF norm (48.64 ± 3.39 vs 36.49 ± 2.82, P = .009), and LF/HF ratio (1.49 ± 0.31 vs 0.73 ± 0.13, P = .009) than the control group. HF norm was significantly lower in the women with PCOS than in the controls (51.38 ± 3.39 vs 63.51 ± 2.82, P = .009). The TP, VLF, and HF showed no significant difference between the groups.The results of the present study indicated that PCOS is related to increased sympathetic modulation in HRV.

Anion gap and base deficit are predictors of mortality in acute pesticide poisoning

BACKGROUND:

Acute pesticide poisoning has long been a serious problem as a method of suicide worldwide. This poisoning is a highly fatal condition that requires a rapid and precise diagnosis for adequate treatment. However, various studies on mortality predictor factors have been insufficient for whole pesticide treatments. We hypothesized that the initial plasma anion gap (AG) and base deficit (BD) are reliable prognostic factors.

METHODS:

A retrospective study analyzed 561 patients with a diagnosis of acute pesticide poisoning between January 1, 2014 and June 30, 2017. The initial AG and BD values were divided into quartiles according to the number of patients. Survival at 30 days from admission was estimated using the Kaplan-Meier survival analysis. Receiver-operator characteristic (ROC) curves were drawn, and the areas under the curve for AG and BD for mortality were calculated.

RESULTS:

Fifty-eight (10.3%) of 561 patients died within 30 days. The highest AG quartile (>22 mEq/L) was associated with an increased risk of 30-day hospital mortality. Compared to patients with an AG less than 14.7 mEq/L, these patients had a 4.18-fold higher risk of 30-day hospital mortality and the highest BD quartile (>7.9 mEq/L) was associated with an increased risk of 30-day hospital mortality. Compared to patients with a BD less than 1.4 mEq/L, these patients had 2.23-fold higher risk of 30-day hospital mortality. The areas under the ROC for AG and BD curve were 0.699 and 0.744, respectively.

CONCLUSIONS:

Initial high AG and BD values could predict mortality and require precise intensive care.

The Role of Charge Balance and Excited State Levels on Device Performance of Exciplex-based Phosphorescent Organic Light Emitting Diodes

The design of novel exciplex-forming co-host materials provides new opportunities to achieve high device performance of organic light emitting diodes (OLEDs), including high efficiency, low driving voltage and low efficiency roll-off. Here, we report a comprehensive study of exciplex-forming co-host system in OLEDs including the change of co-host materials, mixing composition of exciplex in the device to improve the performance. We investigate various exciplex systems using 5-(3-4,6-diphenyl-1,3,5-triazin-2-yl)phenyl-3,9-diphenyl-9H-carbazole, 5-(3-4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9-phenyl-9H-3,9'-bicarbazole, and 2-(3-(6,9-diphenyl-9H-carbazol-4-yl)phenyl)-4-phenylbenzo[4,5]thieno[3,2-d]pyrimidine, as electron transporting (ET: electron acceptor) hosts and 9,9'-dipenyl-9H, 9'H-3,3'-bicarbazole and 9-([1,1'-biphenyl]-4-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole as hole transporting (HT: electron donor) hosts. As a result, a very high current efficiency of 105.1 cd/A at 103 cd/m2 and an extremely long device lifetime of 739 hrs (t95: time after 5% decrease of luminance) are achieved which is one of the best performance in OLEDs. Systematic approach, controlling mixing ratio of HT to ET host materials is suggested to select the component of two host system using energy band matching and charge balance optimization method. Furthermore, our analysis on exciton stability also reveal that lifetime of OLEDs have close relationship with two parameters; singlet energy level difference of HT and ET host and difference of singlet and triplet energy level in exciplex.

Results from the Survey of Antibiotic Resistance (SOAR) 2012-14 in Thailand, India, South Korea and Singapore

OBJECTIVES

To provide susceptibility data for community-acquired respiratory tract isolates of Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae and Moraxella catarrhalis collected in 2012-14 from four Asian countries.

METHODS

MICs were determined using Etest(®) for all antibiotics except erythromycin, which was evaluated by disc diffusion. Susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. For macrolide/clindamycin interpretation, breakpoints were adjusted for incubation in CO2 where available.

RESULTS

Susceptibility of S. pneumoniae was generally lower in South Korea than in other countries. Penicillin susceptibility assessed using CLSI oral or EUCAST breakpoints ranged from 21.2% in South Korea to 63.8% in Singapore. In contrast, susceptibility using CLSI intravenous breakpoints was much higher, at 79% in South Korea and ∼95% or higher elsewhere. Macrolide susceptibility was ∼20% in South Korea and ∼50%-60% elsewhere. Among S. pyogenes isolates (India only), erythromycin susceptibility (∼20%) was lowest of the antibiotics tested. In H. influenzae antibiotic susceptibility was high except for ampicillin, where susceptibility ranged from 16.7% in South Korea to 91.1% in India. South Korea also had a high percentage (18.1%) of β-lactamase-negative ampicillin-resistant isolates. Amoxicillin/clavulanic acid susceptibility for each pathogen (PK/PD high dose) was between 93% and 100% in all countries except for H. influenzae in South Korea (62.5%).

CONCLUSIONS

Use of EUCAST versus CLSI breakpoints had profound differences for cefaclor, cefuroxime and ofloxacin, with EUCAST showing lower susceptibility. There was considerable variability in susceptibility among countries in the same region. Thus, continued surveillance is necessary to track future changes in antibiotic resistance.

Whole-breast US following mammography and breast MRI in newly diagnosed breast cancer patients: can it be more than just a guidance tool for biopsy?

AIM

To evaluate the role of ultrasound (US) following magnetic resonance imaging (MRI) and mammography in patients with newly diagnosed breast cancers by assessing the additional cancer detection rate of US.

MATERIAL AND METHODS

Two hundred and twenty-five women who had undergone 225 MRI examinations followed by US were included. An US-detected additional cancer was defined as a lesion detected using breast US that had not been detected by MRI, and which was shown to be malignant at histopathology. The rate of additional cancer detection, incidence of additional malignancies, positive predictive value (PPV), and false-positive (FP) rate were analysed. Factors associated with an increase in the additional cancer detection rate were analysed.

RESULTS

The additional cancer detection rate was 0% (0/225) for the ipsilateral breast and 0.9% (2/225) for the contralateral breast, and the PPVs were 0% (0/5) and 100% (2/2), respectively. The overall TP:FP ratio was 0.4 (2:5). The additional cancer detection rate was higher for cases with moderate and severe background parenchymal enhancement than cases with minimal and mild background parenchymal enhancement (p=0.003). The additional cancer detection rate for cases with moderate and severe background parenchymal enhancement was 5.7% (2/35) for the contralateral breast (p=0.003).

CONCLUSION

Preoperative breast US following MRI and mammography can help clinicians screen for contralateral cancers with an additional detection rate of 0.9%. Moreover, whole-breast US might be a useful contralateral screening modality in cases with moderate or marked parenchymal enhancement on breast MRI.

High-normal free thyroxine levels are associated with low trabecular bone scores in euthyroid postmenopausal women

Trabecular bone scores (TBS) have recently been developed as a diagnostic tool to assess bone texture. We studied thyroid status and TBS in a population-based cohort and demonstrated that high-normal thyroxine levels are associated with low TBS in healthy euthyroid postmenopausal women.

INTRODUCTION

Increased thyroid hormone levels affect bone mineral density (BMD) and, if untreated, increase the risk of fracture. However, the relationship between thyroid function and bone microarchitecture has not yet been established. Trabecular bone scores (TBS) are gray-level textural measurements of dual energy X-ray absorptiometry (DXA) images. The TBS has been proposed as an indirect index of bone microarchitecture. The goal of this study was to characterize the relationship between thyroid function and TBS in euthyroid men and postmenopausal euthyroid women.

METHODS

A total of 1376 euthyroid subjects (648 postmenopausal women and 728 men) were recruited from a community-based cohort in Korea. Free thyroxine (fT4) levels, thyroid stimulating hormone (TSH) levels, BMD, and TBS were measured and compared.

RESULTS

There was no significant relationship between either fT4 or TSH levels and BMD in men and women. Multiple linear regression analysis showed that high-normal fT4 levels were negatively correlated with TBS (β = -0.111; P = 0.002, after adjusting for both age and body mass index [BMI]) in postmenopausal women. In men, however, there was no significant correlation between fT4 levels and TBS. TSH levels were not significantly associated with TBS in either men or women.

CONCLUSION

Higher fT4 levels within the normal reference range are associated with deterioration of trabecular microarchitecture in healthy euthyroid postmenopausal women.

The Effect of General Anesthesia on Aminotransferase Levels in Patients with Elevated Aminotransferase Levels: A Single-Center 5-Year Retrospective Study

BACKGROUND

The effect of commonly used anesthetics on postoperative aminotransferase levels in patients with preoperatively elevated values is unclear.

METHODS

The medical records of 25,567 adult patients undergoing elective general anesthesia were retrospectively reviewed. Patients were classified into normal (≤ 40 IU/L), mild (41-119 IU/L), moderate (120-199 IU/L), and marked elevation (200+ IU/L) groups according to their preoperative alanine aminotransferase levels. Changes in these levels before and after general anesthesia were compared according to the anesthetics used.

RESULTS

Among the patients with preoperative mild or moderate elevation, 97.8% (2589/2647) did not show a higher alanine aminotransferase level after surgery. Compared with total IV anesthesia (TIVA), sevoflurane showed adjusted odds ratios (95% confidence interval) of 1.27 (1.10-1.46) for mild, 1.33 (0.86-2.05) for moderate, and 3.35 (1.58-7.04) for marked postoperatively elevated levels of alanine aminotransferase versus normal levels. Similarly, compared with TIVA, desflurane showed adjusted odds ratios (95% confidence interval) of 1.21 (0.96-1.53) for mild, 1.44 (0.70-2.94) for moderate, and 3.18 (1.14-8.89) for marked postoperatively elevated levels of alanine aminotransferase versus normal levels (P = 0.05).

CONCLUSIONS

In most cases, postoperative alanine aminotransferase levels did not worsen even in patients with preoperatively elevated levels. Sevoflurane was associated with increased odds for postoperative elevation of these levels after general surgery compared with TIVA.

Constitutively active Ras negatively regulates Erk MAP kinase through induction of MAP kinase phosphatase 3 (MKP3) in NIH3T3 cells

The Ras/Raf/MEK/Erk signaling pathway is important for regulation of cell growth, proliferation, differentiation, survival, and apoptosis in response to a variety of extracellular stimuli. Lack of Erk MAPK activation is observed in several cancer cells despite active activation of Ras. However, little is known about the modulation of Erk1/2 activity by active Ras. Here, we show that overexpression of active H-Ras (H-RasG12R) in NIH3T3 fibroblasts impaired FGF2-induced Erk1/2 phosphorylation, as compared to wild-type cells. Northern blot analysis revealed that prolonged expression of active Ras increased MAP kinase phosphatase 3 (MKP3) mRNA expression, a negative regulator of Erk MAPK. Inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway abrogated active Ras-induced up-regulation of MKP3 expression, leading to the rescue of Erk1/2 phosphorylation. Our results demonstrated that the Ras/Raf/MEK/Erk signaling cascade is negatively regulated by the PI3K/Akt dependent transcriptional activation of the MKP3 gene.

Fabrication and characteristics of GaN-based light-emitting diodes with a reduced graphene oxide current-spreading layer

A reduced graphene oxide (GO) layer was produced on undoped and n-type GaN, and its effect on the current- and heat-spreading properties of GaN-based light-emitting diodes (LEDs) was studied. The reduced GO inserted between metal electrode and GaN semiconductor acted as a conducting layer and enhanced lateral current flow in the device. Especially, introduction of the reduced GO layer on the n-type GaN improved the electrical performance of the device, relative to that of conventional LEDs, due to a decrease in the series resistance of the device. The enhanced current-spreading was further of benefit, giving the device a higher light output power and a lower junction temperature at high injection currents. These results therefore indicate that reduced GO can be a suitable current and heat-spreading layer for GaN-based LEDs.

Size dependence of silica nanospheres embedded in 385 nm ultraviolet light-emitting diodes on a far-field emission pattern

We demonstrate that the use of silica nanospheres (SNs) with sizes close to the emission wavelength of light-emitting diodes (LEDs) can enhance the light output power and manipulate the far-field emission pattern. Near-ultraviolet (NUV)-LEDs grown on a patterned sapphire substrate embedded with 300 nm SNs show a three times higher light output power than that without SNs, when measured through the top side. For far-field emission measurements, the LEDs embedded with 300 nm SNs show the significant increase of front emission due to the improved crystal quality of epitaxial films as well as the increase of Mie scattering effect of SNs. These experimental results indicate the important role of the size of embedded SNs in enhancing the light output power for NUV-LEDs.

Investigation of thermal and electrical stabilities of a GdBCO coil using grease as an insulation material for practical superconducting applications

This paper presents the effects of thermal grease on the electrical and thermal characteristics of GdBCO pancake coils, observed through charge-discharge, sudden discharge, over-current, and thermal quench testing. In charge-discharge and sudden discharge tests, a coil using thermal grease as an insulation material demonstrated faster charging/discharging rates compared to a coil without turn-to-turn insulation. In the case of over-current tests, the coil using thermal grease exhibited the highest electrical stability. Furthermore, thermal quench testing showed the coil employing thermal grease to possess superior thermal characteristics, with rapid cooling and low temperature rise. Overall, the use of thermal grease as an insulation material may be a potential solution to the problems observed with the existing insulation materials, possessing fast charging/discharging rates with superior thermal and electrical stabilities.

CD11a, CD11c, and CD18 gene polymorphisms and susceptibility to Behçet's disease in Koreans

Lesions of Behçet's disease (BD) show vascular infiltrates of immune cells expressing integrins. β2 integrins (CD11/CD18) play a major role in cell migration to the inflammatory lesion and also induce cytokine production. Thus, genetic polymorphisms of CD11/CD18 may be associated with the pathogenesis of BD. In this study, nine single nucleotide polymorphisms (SNPs) of the CD11a, CD11c, and CD18 were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and haplotype analysis in 305 BD patients and 266 healthy controls. The frequencies of genotype rs11574944 CC and haplotype rs11574944C-rs2230433G-rs8058823A in CD11a were significantly lower in BD patients. The frequencies of genotype rs2230429 CC, rs2929 GG, and haplotype rs2230429C-rs2929G in CD11c were higher in BD patients. The frequencies of genotype rs235326CC and haplotype rs2070946A-rs235326C-rs760456G-rs684G in CD18 were significantly higher in the BD patients than in the controls. Other SNPs in CD11a, CD11c, and CD18 gene were not significantly different. Therefore, the major genotype and haplotype of CD11a/CD18 may play a role in decreasing the susceptibility of BD, whereas the major genotype and haplotype of CD11c/CD18 may play a role in increasing the susceptibility of BD.

Takotsubo cardiomyopathy caused by pulmonary tuberculosis: a case report

Takotsubo cardiomyopathy (TTC) is defined as a reversible, acute ventricular dysfunction without any evidence of coronary artery obstruction. There have been reports of TTC caused by emotional or physical stress, drug use, hormone imbalance, or medical conditions such as pulmonary disease, sepsis, and trauma, but a relationship between TTC and pulmonary tuberculosis has not previously been reported. From our knowledge, this is the first report of TTC caused by pulmonary tuberculosis.

Role of the superior turbinate when performing endoscopic endonasal transsphenoidal approach

BACKGROUND

This study examined the relationship between the superior turbinate and natural ostium of the sphenoid sinus, as seen during the endoscopic endonasal transsphenoidal approach (EETSA) for sellar lesions and described how to enter the sphenoethmoid cell safely for complete exposure of the sellar floor, including adjacent vital structures such as the prominence of the optic nerve and carotid artery.

MATERIALS AND METHODS

This study retrospectively reviewed the medical records and operative findings of 154 patients, who underwent EETSA between February 2009 and February 2011. We evaluated the location of the natural ostium of the sphenoid sinus relative to the superior turbinate and revealed the clinical significance of the superior turbinate as a surgical guide to enter into the sphenoethmoid cell during EETSA.

RESULTS

The natural ostium of the sphenoid sinus was located medially to the posteroinferior end of the superior turbinate in 151 (98%) patients. In 1 patient, the natural ostia of the sphenoid sinus were located lateral to the superior turbinate bilaterally. Sphenoethmoid cell was encountered in 53 (34%) patients. We could easily enter the sphenoethmoid cell at the point where the superior turbinate was attached to the anterior wall of the sphenoid sinus.

CONCLUSIONS

The superior turbinate is a good surgical landmark for identifying the natural ostium of the sphenoid sinus and as a guide for the surgical entrance to the sphenoethmoid cell extending to the sphenoid sinus during EETSA.

Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

Phylogenetic relationships of chrysanthemums in Korea based on novel SSR markers

Chrysanthemums are well known for their esthetic and medicinal values. Characterization of chrysanthemums is vital for their conservation and management as well as for understanding their genetic relationships. We found 12 simple sequence repeat markers (SSRs) of 100 designed primers to be polymorphic. These novel SSR markers were used to evaluate 95 accessions of chrysanthemums (3 indigenous and 92 cultivated accessions). Two hundred alleles were identified, with an average of 16.7 alleles per locus. KNUCRY-77 gave the highest polymorphic information content value (0.879), while KNUCRY-10 gave the lowest (0.218). Similar patterns of grouping were observed with a distance-based dendrogram developed using PowerMarker and model-based clustering with Structure. Three clusters with some admixtures were identified by model-based clustering. These newly developed SSR markers will be useful for further studies of chrysanthemums, such as taxonomy and marker-assisted selection breeding.

Air-ring microstructure arrays for enhanced light extraction from a face-up light-emitting diode

In this Letter, a light-emitting diode (LED) with prism-shaped-air-ring microstructures (PSAMs) formed on flat sapphire substrate is demonstrated as an alternative design to face-up LEDs on patterned sapphire substrate (PSS) for enhanced light extraction efficiency. In this LED design, the emitted photons can be deflected to the top of the chip for its effective extraction, contrary to the PSS-LED wherein photons are guided to sapphire and get absorbed by packaging materials. The PSAM-LED showed an enhancement in the radiometric power as high as 10% with a low far-field angle of 129° over that of a PSS-LED under an injection current of 20 mA.

Association rule mining and network analysis in oriental medicine

Extracting useful and meaningful patterns from large volumes of text data is of growing importance. In the present study we analyze vast amounts of prescription data, generated from the book of oriental medicine to identify the relationships between the symptoms and the associated medicines used to treat these symptoms. The oriental medicine book used in this study (called Bangyakhappyeon) contains a large number of prescriptions to treat about 54 categorized symptoms and lists the corresponding herbal materials. We used an association rule algorithm combined with network analysis and found useful and informative relationships between the symptoms and medicines.

The Effects of Female Shell Size on Reproductive Potential of the Egg Capsule in Rapa Whelk Rapana venosa in Three Regions of Different Salinities

We investigated the effects of shell height on reproductive potential of the female Rapana venosa in three regions of different salinities (the coastal zone of the Gwangyang Bay (S-1); the upper reaches (S-3); lower reaches (S-2) of the Seomjin River). The number of egg capsules, egg capsule height, and fecundity associated with reproductive potential of larger female rapa whelks were higher than those of smaller individuals in all three regions. Correlation analyses showed that there is a significant positive correlation between egg capsule and female shell height. Mean of shell heights, egg capsule heights, the number of egg capsules in an egg mass, and fecundity in an egg capsule produced from female individuals inhabiting S-1 region were markedly higher than those inhabiting S-2 and S-3 regions. In particular, the fecundity of the rapa whelk increased with the salinity and shell height. Although large rapa whelks produced a large number of egg capsules at S-1 region, those at S-3 habitat laid less egg capsules with smaller size. If these rapa whelks were put into S-2 region, the number of egg capsules produced by a female at S-2 region was slightly larger than those produced by a female at S-3 region. This provides a clear evidence that the number of the egg capsules can be controlled by the salinity. In the coastal zone of the Gwangyang Bay and the upper reaches of Seomjin River, the fecundity of this species was estimated to be approximately 182,000-1,302,000 eggs/ind./yr.

The glucagon-like peptide-1 receptor agonist exenatide restores impaired pro-islet amyloid polypeptide processing in cultured human islets: implications in type 2 diabetes and islet transplantation

AIMS/HYPOTHESIS

Islet amyloid, formed by aggregation of human islet amyloid polypeptide (hIAPP), is associated with beta cell death in type 2 diabetes as well as in cultured and transplanted human islets. Impaired prohIAPP processing due to beta cell dysfunction is implicated in hIAPP aggregation. We examined whether the glucagon-like peptide-1 receptor (GLP-1R) agonist exenatide can restore impaired prohIAPP processing and reduce hIAPP aggregation in cultured human islets and preserve beta cell function/mass during culture conditions used in clinical islet transplantation.

METHODS

Isolated human islets (n = 10 donors) were cultured with or without exenatide in normal or elevated glucose for 2 or 7 days. Beta cell apoptosis, proliferation, mass, function, cJUN N-terminal kinase (JNK) and protein kinase B (PKB) activation and amyloid formation were assessed. ProhIAPP, its intermediates and mature hIAPP were detected.

RESULTS

Exenatide-treated islets had markedly lower JNK and caspase-3 activation and beta cell apoptosis, resulting in higher beta/alpha cell ratio and beta cell area than non-treated cultured islets. Exenatide improved beta cell function, manifested as higher insulin response to glucose and insulin content, compared with non-treated cultured islets. Phospho-PKB immunoreactivity was detectable in exenatide-treated but not untreated cultured islets. Islet culture caused impaired prohIAPP processing with decreased mature hIAPP and increased NH(2)-terminally unprocessed prohIAPP levels resulting in higher release of immature hIAPP. Exenatide restored prohIAPP processing and reduced hIAPP aggregation in cultured islets.

CONCLUSIONS/INTERPRETATION

Exenatide treatment enhances survival and function of cultured human islets and restores impaired prohIAPP processing in normal and elevated glucose conditions thereby reducing hIAPP aggregation. GLP-1R agonists may preserve beta cells in conditions associated with islet amyloid formation.

Effect of co-existing copper and calcium on the removal of As(V) by reused aluminum oxides

Among the various heavy metals, arsenic is frequently found in abandoned mine drainage and the environmental fate of arsenic in real aqueous solutions can be highly dependent on the presence of co-existing ions. In this study, removal of arsenate through adsorption on the reused aluminum oxide or through precipitation was investigated in a single and in a binary system as a function of pH and concentration. Different removal behaviors of arsenate were observed in the presence of different cations as well as a variation of the molar ratios of arsenate to cations. Co-operative effects on arsenate removal by precipitation in solution occurred with an increase of copper concentration, while a decrease of arsenate removal resulted in increasing calcium concentration. It was observed that the arsenate removal in the presence of calcium would be highly dependent on the molar ratios of both elements.

Updates and perspectives on the utilization of molecular makers of complex traits in rice

After complete sequencing of its genome and annotation of the majority of its ~32,000 genes, rice genome has become the model genome among the cereal genomes, and the focus has shifted from structural to functional genomics and application of genomic-derived information in rice breeding. During the past 2 decades, intensive worldwide efforts have led to significant improvements in rice. An abundance of molecular markers and information related to many genes/quantitative trait loci that control agronomically important traits such as yield, quality, and biotic and abiotic stress tolerance have been identified. Bridging the application gap between quantitative trait locus identification and marker-assisted selection breeding is an urgent, arduous, and long-term task. Marker development, allele mining, gene discovery, and molecular breeding have progressed to a great extent because of the rapid development of next-generation sequencing, large-scale high-density genotyping, and genome-wide selection strategies. The availability of high-density markers and the rapidly decreasing cost of genotyping have facilitated marker-assisted selection of many traits that were previously not possible.

Nanoscale characterization of acid and thermally treated collagen fibrils

Type I collagen is a major extracellular matrix component and its hierarchical structure plays an essential role in the regulation of cellular behavior. Here, we have analyzed the changes in the morphological, chemical, and mechanical properties of collagen fibrils induced by acidic and thermal treatments and the influence on the cellular response of MC3T3-E1 cells. Morphological changes induced by the disintegration of the fibrillar structure of collagen were observed using atomic force microscopy. The changes in the surface chemistry due to the disassembly of native collagen fibrils were observed using time-of-flight secondary ion mass spectroscopy (ToF-SIMS). ToF-SIMS spectra were very sensitive to changes in the molecular configuration of the collagen fibrils induced by acidic and thermal treatments due to the extreme surface specificity. In addition, ToF-SIMS showed clear and reproducible changes in the surface amino acid composition corresponding to the acidic and thermal treatments of collagen fibrils. Based on the quantitative map of surface elastic modulus measured by contact-resonance force microscopy, acid and thermally treated collagen showed a lower elastic modulus than native collagen fibrils. Compared with native collagen fibrils, reduced cell spreading and decreased viability of MC3T3-E1 cells were observed on both the acid and thermally treated collagen.

High performance of InGaN light-emitting diodes by air-gap/GaN distributed Bragg reflectors

The effect of air-gap/GaN DBR structure, fabricated by selective lateral wet-etching, on InGaN light-emitting diodes (LEDs) is investigated. The air-gap/GaN DBR structures in LED acts as a light reflector, and thereby improve the light output power due to the redirection of light into escape cones on both front and back sides of the LED. At an injection current of 20 mA, the enhancement in the radiometric power as high as 1.91 times as compared to a conventional LED having no DBR structure and a far-field angle as low as 128.2° are realized with air-gap/GaN DBR structures.

Risk factors related to interfractional variation in whole pelvic irradiation for locally advanced pelvic malignancies

PURPOSE

The goal of the present study was to demonstrate risk factors affecting the interfractional variation in whole pelvic irradiation.

PATIENTS AND METHODS

Daily image acquisitions of 101 patients with locally advanced pelvic malignancy were undertaken using a kilo-voltage orthogonal on-board imager. The baseline deviation (the shift between the initial treatment and each fraction; Value(Base)) and day-to-day variation (the shift between the previous treatment and each fraction; Value(DD)) were measured. The standard deviations (SD) along the x- (right-left), y- (cranial-caudal), and z- (anterior-posterior) axes (SD[x], SD[y], and SD[z], respectively), the 3D vector of the SD (SD[3D]), and the mean of 3D shift (mean[3D]) were calculated in each patient. Various clinical factors, lumbar pelvic balance and rotation, and the shift of 5 consecutive fractions from the initial treatment (Value(5Fx)) were investigated as risk factors.

RESULTS

The prone set-up showed a larger mean(Base)[3D] than in the supine position (p =0 .063). A body mass index (BMI) ≥ 30 kg/m(2) resulted in the largest mean(DD)[3D] (p = 0.078) and SD(DD)[3D] (p = 0.058). All the SD(5Fx) along the x-, y-, and z-axes had moderate linear relationships with SD(Base) and SD(DD) (p < 0.001). The SD(5Fx)[3D] also had a moderate linear relationship with the mean(Base)[3D], mean(DD)[3D], SD(Base)[3D], and SD(DD)[3D] (p < 0.001). In multivariate analysis, the SD(5Fx) had the same significant relationship with SD(Base) and SD(DD) (p < 0.001). A BMI ≥ 30 kg/m(2) was associated with the largest SD(DD)[x] (p = 0.003).

CONCLUSION

Close surveillance through high-quality and frequent image guidance is recommended for patients with extensive variations of the initial five consecutive fractions or obesity.

Deletion of Fas protects islet beta cells from cytotoxic effects of human islet amyloid polypeptide

AIMS/HYPOTHESIS: Islet amyloid, which is mainly composed of human islet amyloid polypeptide (hIAPP), is a pathological characteristic of type 2 diabetes and also forms in cultured and transplanted islets. We used islet beta cells as well as two ex vivo models of islet amyloid formation, cultured human islets and hIAPP-expressing transgenic mouse islets with or without beta cell Fas deletion, to test whether: (1) the aggregation of endogenous hIAPP induces Fas upregulation in beta cells; and (2) deletion or blocking of Fas protects beta cells from amyloid toxicity. METHODS: INS-1, mouse or human islet cells were cultured with hIAPP alone, or with amyloid inhibitor or Fas antagonist. Non-transduced islets, and human islets or hIAPP-expressing mouse islets transduced with an adenovirus that delivers a human proIAPP-specific small interfering RNA (siRNA) (Ad-ProhIAPP-siRNA) were cultured to form amyloid. Mouse islets expressing hIAPP with or without Fas were similarly cultured. Beta cell Fas upregulation, caspase-3 activation, apoptosis and function, and islet IL-1β levels were assessed. RESULTS: hIAPP treatment induced Fas upregulation, caspase-3 activation and apoptosis in INS-1 and islet cells. The amyloid inhibitor or Fas antagonist reduced apoptosis in hIAPP-treated beta cells. Islet cells with Fas deletion had lower hIAPP-induced beta cell apoptosis than those expressing Fas. Ad-ProhIAPP-siRNA-mediated amyloid inhibition reduced Fas upregulation and IL-1β immunoreactivity in human and hIAPP-expressing mouse islets. Cultured hIAPP-expressing mouse islets with Fas deletion had similar amyloid levels, but lower caspase-3 activation and beta cell apoptosis, and a higher islet beta:alpha cell ratio and insulin response to glucose, compared with islets expressing Fas and hIAPP. CONCLUSIONS/INTERPRETATION: The aggregation of biosynthetic hIAPP produced in islets induces beta cell apoptosis, at least partially, via Fas upregulation and the Fas-mediated apoptotic pathway. Deletion of Fas protects islet beta cells from the cytotoxic effects of endogenously secreted (and exogenously applied) hIAPP.