Simulation of a Multistaggered Baffle Scrubber to Enhance the Efficiency of Simultaneous Desulfurization and Denitrification

In this study, we conduct simulation research on simultaneous desulfurization and denitrification in a multistaggered baffle spray scrubber. By employing two-phase flow simulations within the Euler-Lagrange framework and calculating the gas-liquid mass transfer rate with user-defined functions, we comprehensively analyzed the effects of various operational parameters. Initially, we validated our simulation model by comparing the simulation results with experimental data. Under conditions of a 0.2 mm droplet diameter, a liquid-to-gas ratio (L/G) of 12 L/m3, and a gas flow rate of 5 CMM using a full cone nozzle, the simulation indicated a desulfurization efficiency of 99.90 versus 99.84% obtained experimentally and a denitrification efficiency of 92.01 versus 90.67% obtained experimentally. This comparison confirmed the reliability of the simulation model. Our findings indicate that a droplet size of 2 mm is optimal, enhancing the desulfurization efficiency from 99.90 to 99.98% and the denitrification efficiency from 92.01 to 99.76%. However, when the droplet size exceeds 2 mm, efficiencies marginally decrease. Increasing the liquid-to-gas ratio to 16 L/m3 further improves desulfurization and denitrification efficiencies to 99.98 and 99.80%, respectively. In contrast, higher inlet flue gas flow rates reduce these efficiencies, with a decline observed from 100% to as low as 93.90% for denitrification with 2 mm droplets. Additionally, the use of a swirl cone nozzle, compared to full or hollow cone nozzles, better disperses droplets, enhancing the gas-liquid contact and achieving efficiencies of 99.99% for desulfurization and 99.81% for denitrification with 2 mm droplets. These insights are valuable for optimizing operational conditions in industrial-scale spray scrubbers, significantly contributing to mitigating the environmental impacts of industrial emissions.

Association between waist circumference change after smoking cessation and incidence of hypertension in Korean adults

OBJECTIVES

This study investigates the association between smoking cessation and hypertension incidence, as well as the association between waist circumference change after smoking cessation and hypertension incidence.

STUDY DESIGN

This was a nationwide population-based cohort study.

METHODS

We used the Korean Health Screening Cohort data and included 158,505 participants who had undergone two or more health examinations between 2008 and 2011, with follow-ups throughout 2019. Smoking cessation and waist changes were captured based on difference between first and follow-up screening dates. Hazard ratio (HR) and 95% confidence interval (CI) for hypertension risk were estimated using multivariable Cox proportional hazard regression models.

RESULTS

There were 31,270 cases of hypertension during a median follow-up of 8.50 years. After adjusting for potential confounding factors, HR for hypertension were 1.01 (95% CI: 0.97-1.05), 0.91 (95% CI: 0.87-0.95), and 0.88 (95% CI: 0.85-0.91) for recent quitters, long-term quitters, and non-smokers, respectively, compared with current smokers. HR for hypertension, compared with current smokers, were 0.89 (95% CI: 0.84-0.94), 0.91 (95% CI: 0.85-0.97), and 0.99 (95% CI: 0.91-1.08) for long-term quitters with no waist gain, long-term quitters with waist gain of 0.1-5.0 cm, and long-term quitters with waist gain of ≥5.0 cm, respectively.

CONCLUSIONS

Long-term smoking cessation was significantly associated with decreased risk of hypertension, and long-term smoking cessation with no waist gain or less than 5.0 cm of waist gain was significantly associated with decreased risk of hypertension. However, more than 5.0 cm of waist gain can attenuate the effect of long-term smoking cessation on lowering the risk of hypertension.

Effects of hip joint kinematics on the effective pelvis stiffness and hip impact force during simulated sideways falls

Improved understanding is required on how hip fracture risk is influenced by landing configuration. We examined how hip impact dynamics was affected by hip joint kinematics during simulated sideways falls. Twelve young adults (7 males, 5 females) of mean age 23.5 (SD = 1.5) years, participated in pelvis release experiments. Trials were acquired with the hip flexed 15° and 30° for each of three hip rotations: +15° ("external rotation"), 0°, and -15° ("internal rotation"). During falls, force-deformation data of the pelvis were recorded. Outcome variables included the peak hip impact force (Fexperimental) and effective stiffness of the pelvis (k1st, ksecant, and kms) determined with different methods suggested in literature, and predicted hip impact force during a fall from standing height (F1st, Fsecant and Fms). The two-way repeated-measures ANOVA was used to test whether these variables were associated with hip joint angles. The Fexperimental, ksecant and Fsecant were associated with hip rotation (F = 5.587, p = 0.005; F = 9.278, p < 0.0005; F = 5.778, p = 0.004, respectively), and 15 %, 31 % and 17 % smaller in 15° external than internal rotation (848 versus 998 N; 24.6 versus 35.6 kN/m; 2,637 versus 3,170 N, respectively). However, none of the outcome variables were associated with hip flexion (p > 0.05). Furthermore, there were no interactions between the hip rotation and flexion for all outcome variables (p > 0.05). Our results provide insights on hip impact dynamics, which may help improve a hip model to assess hip fracture risk during a fall.

Topological magnetic structure generation using VAE-GAN hybrid model and discriminator-driven latent sampling

Recently, deep generative models using machine intelligence are widely utilized to investigate scientific systems by generating scientific data. In this study, we experiment with a hybrid model of a variational autoencoder (VAE) and a generative adversarial network (GAN) to generate a variety of plausible two-dimensional magnetic topological structure data. Due to the topological properties in the system, numerous and diverse metastable magnetic structures exist, and energy and topological barriers separate them. Thus, generating a variety of plausible spin structures avoiding those barrier states is a challenging problem. The VAE-GAN hybrid model can present an effective approach to this problem because it brings the advantages of both VAE's diversity and GAN's fidelity. It allows one to perform various applications including searching a desired sample from a variety of valid samples. Additionally, we perform a discriminator-driven latent sampling (DDLS) using our hybrid model to improve the quality of generated samples. We confirm that DDLS generates various plausible data with large coverage, following the topological rules of the target system.

Super-resolution of magnetic systems using deep learning

We construct a deep neural network to enhance the resolution of spin structure images formed by spontaneous symmetry breaking in the magnetic systems. Through the deep neural network, an image is expanded to a super-resolution image and reduced to the original image size to be fitted with the input feed image. The network does not require ground truth images in the training process. Therefore, it can be applied when low-resolution images are provided as training datasets, while high-resolution images are not obtainable due to the intrinsic limitation of microscope techniques. To show the usefulness of the network, we train the network with two types of simulated magnetic structure images; one is from self-organized maze patterns made of chiral magnetic structures, and the other is from magnetic domains separated by walls that are topological defects of the system. The network successfully generates high-resolution images highly correlated with the exact solutions in both cases. To investigate the effectiveness and the differences between datasets, we study the network's noise tolerance and compare the networks' reliabilities. The network is applied with experimental data obtained by magneto-optical Kerr effect microscopy and spin-polarized low-energy electron microscopy.

Primary hepatic mucosa-associated lymphoid tissue lymphoma mimicking hepatocellular carcinoma in a patient with chronic hepatitis B: a case report

Primary hepatic lymphoma is a rare disease, and primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma accounts for only 0.3% of all primary hepatic lymphomas. Herein, we report a case of primary hepatic MALT lymphoma in a male patient in his mid-40 s with chronic hepatitis B infection. The patient visited our department for further examination of a hepatic nodule initially visualized through abdominal pelvic computed tomography (CT). Based on imaging studies and elevated levels of tumor markers, the tumor was suspected to be hepatocellular carcinoma. A laparoscopic inferior sectionectomy (segment 5 and 6) was performed, and immunohistochemical staining revealed that the tumor was positive for CD20, B-cell lymphoma 2, pan-cytokeratin (CK), and CK19 markers. Pathological findings revealed it to be a primary hepatic MALT lymphoma. After surgery, bone marrow biopsies and fluorodeoxyglucose-positron emission tomography integrated with CT scanning confirmed that there was no other involvement. The patient did not receive chemotherapy, and there was no recurrence during the 24-month follow-up period. Hepatocellular carcinoma is the most common malignancy in patients with chronic hepatitis B, but rare tumors such as primary MALT lymphoma can also occur, so a careful approach is required for their differentiation.

Isolated posterior inferior cerebellar artery dissection with ischaemic stroke: evaluating the radiological features and diagnostic feasibility of high-resolution vessel wall imaging

AIM

To evaluate the radiological features of isolated posterior inferior cerebellar artery dissection (PICAD) and the feasibility of using high-resolution vessel-wall imaging (HR-VWI) for diagnosing PICAD.

MATERIALS AND METHODS

Three hundred and nine patients with arterial dissection involving the posterior cerebral circulation, who underwent HR-VWI between March 2012 and July 2019 were reviewed retrospectively. Among them, 44 patients (14.2%) were diagnosed with isolated PICAD in consensus among a neuroradiologist, a neurointerventionist, and a neurologist. Two neuroradiologists reviewed the vessel wall images independently for evidence of dissection (dissection flap, outer diameter enlargement on T2-weighted imaging [WI], mural haematoma). Diagnostic confidence was also scored on a five-point scale. Intra- and interobserver agreement for diagnosing PICAD and detecting evidence of dissection were evaluated.

RESULTS

Dissection flaps were seen on T2WI in all cases (100%) and on contrast-enhanced T1WI in 34 patients (79.1%). Outer diameter enlargement of the steno-occlusive lesions on angiography was detected in most cases (97.7%). A mural haematoma was detected on three-dimensional (3D) contrast-enhanced motion-sensitised driven-equilibrium T1WI in 97.1% of the cases. The mean diagnostic confidence score derived by two neuroradiologists was 4.72. The two reviewers showed substantial to almost perfect agreement (weighted kappa coefficient: 0.62-0.97).

CONCLUSION

Use of HR-VWI as a diagnostic tool for PICAD is feasible, and a dissection flap with outer wall enlargement on HR-T2WI allows confident dissection diagnosis. The present data suggest that PICAD might be considered as a stroke aetiology in patients with unexplained ischaemic stroke in the PICA territory, and that PICA evaluation with HR-VWI is both necessary and feasible.

The Efficacy of a Novel Type of Integrated Knife for Endoscopic Submucosal Dissection in Early Gastric Cancer

Background/Aims: This study aimed to compare the efficacy of a recently developed clear-cut knife with that of widely used knives for endoscopic submucosal dissection (ESD) in early gastric cancer (EGC).Materials and Methods: Data were collected retrospectively from the National Health Insurance Service Ilsan Hospital between May 2017 and April 2019. The study included 105 patients (108 lesions) with EGC who underwent ESD. Fifty-six EGCs were dissected using an insulation-tipped diathermic knife in combination with a needle knife, while 52 EGCs were dissected using a clear-cut knife, a single device with an integrated needle and an insulated-tipped knife. Oncologic outcomes and technical success were compared between the two groups.Results: The distribution of the tumor locations, composition of the undifferentiated types of EGCs, and the size of EGCs (14.3±8.0 vs. 16.6±7.3 mm; P=0.130) were not significantly different between the groups. The complete (98.2% vs. 94.2%; P=0.273) and curative (87.5% vs. 88.5%; P=0.878) resection rates were not statistically different. Furthermore, no significant difference between the total procedure times (39±34.1 vs. 35.7±20.1 minutes; P=0.554), areas of the dissected specimen (858.6±406.5 vs. 980.3±393.8 mm2; P=0.119) and dissected areas per minute (32.4±17.9 vs. 35.5±16.2 mm²/min; P=0.345) were noted. Regarding complications, the overall perforation rates (3.6% vs. 4.0%) and bleeding rates (3.6% vs. 8.0%) were not statistically different.Conclusions: The newly developed clear-cut knife is as useful as the combination of classical knives for ESD in EGC.

Estimating the effective fields of spin configurations using a deep learning technique

The properties of complicated magnetic domain structures induced by various spin-spin interactions in magnetic systems have been extensively investigated in recent years. To understand the statistical and dynamic properties of complex magnetic structures, it is crucial to obtain information on the effective field distribution over the structure, which is not directly provided by magnetization. In this study, we use a deep learning technique to estimate the effective fields of spin configurations. We construct a deep neural network and train it with spin configuration datasets generated by Monte Carlo simulation. We show that the trained network can successfully estimate the magnetic effective field even though we do not offer explicit Hamiltonian parameter values. The estimated effective field information is highly applicable; it is utilized to reduce noise, correct defects in the magnetization data, generate spin configurations, estimate external field responses, and interpret experimental images.

Effectiveness of Hepatocellular Carcinoma Surveillance and an Optimal Surveillance Interval: Nationwide Cohort of Korea

PURPOSE

To assess associations between surveillance intervals in a national hepatocellular carcinoma (HCC) surveillance program and receiving curative treatment and mortality using nationwide cohort data for Korea.

MATERIALS AND METHODS

Using the National Health Insurance Service Database of Korea, we retrospectively identified 3201852 patients, the target population of the national HCC surveillance program, between 2008 and 2017. After exclusion, a total of 64674 HCC patients were divided based on surveillance intervals: never screened, ≤6 months (6M), 7-12 months (1Y), 13-24 months (2Y), and 25-36 months (3Y). Associations for surveillance interval with the chance to receive curative therapy and all-cause mortality were analyzed.

RESULTS

The 6M group (51.9%) received curative therapy more often than the other groups (1Y, 48.3%; 2Y, 43.8%; 3Y, 41.3%; never screened, 34.5%). Odds ratio for receiving curative therapy among the other surveillance interval groups (1Y, 0.87; 2Y, 0.76; 3Y, 0.77; never screened, 0.57; p<0.001) were significantly lower than that of the 6M group. The hazard ratios (HRs) of all-cause mortality were 1.07, 1.14, and 1.37 for 2Y, 3Y, and never screened groups. The HR for the 1Y group (0.96; p=0.092) was not significantly different, and it was lower (0.91; p<0.001) than that of the 6M group after adjustment for lead-time bias. Curative therapy was associated with survival benefits (HR, 0.26; p<0.001).

CONCLUSION

HCC surveillance, especially at a surveillance interval of 6 months, increases the chance to receive curative therapy.

The Safety of Intra-arterial Tirofiban during Endovascular Therapy after Intravenous Thrombolysis

BACKGROUND AND PURPOSE

The safety and efficacy of tirofiban during endovascular therapy in patients undergoing intravenous thrombolysis with recombinant IV tPA remain unclear. This study aimed to investigate the safety and efficacy of intra-arterial tirofiban use during endovascular therapy in patients treated with IV tPA.

MATERIALS AND METHODS

Using a multicenter registry, we enrolled patients with acute ischemic stroke who underwent endovascular therapy. Safety outcomes included postprocedural parenchymal hematoma type 2 and/or thick subarachnoid hemorrhage, intraventricular hemorrhage, and 3-month mortality. Efficacy outcomes included the successful reperfusion rate, postprocedural reocclusion, and good outcomes at 3 months (mRS scores of 0-2). The tirofiban effect on the outcomes was evaluated using a multivariable analysis while adjusting for potential confounders.

RESULTS

Among enrolled patients, we identified 314 patients with stroke (279 and 35 patients in the no tirofiban and tirofiban groups, respectively) due to an intracranial artery occlusion who underwent endovascular therapy with intravenous thrombolysis. A multivariable analysis revealed no association of intra-arterial tirofiban with postprocedural parenchymal hematoma type and/or thick subarachnoid hemorrhage (adjusted OR, 1.07; 95% CI, 0.20-4.10; P = .918), intraventricular hemorrhage (adjusted OR, 0.43; 95% CI, 0.02-2.85; P = .467), and 3-month mortality (adjusted OR, 0.38; 95% CI, 0.04-1.87; P = .299). Intra-arterial tirofiban was not associated with good outcome (adjusted OR, 2.22; 95% CI, 0.89 -6.12; P = .099).

CONCLUSIONS

Using intra-arterial tirofiban during endovascular therapy after IV tPA could be safe.

Prediction of the risk of developing hepatocellular carcinoma in health screening examinees: a Korean cohort study

Background

Almost all Koreans are covered by mandatory national health insurance and are required to undergo health screening at least once every 2 years. We aimed to develop a machine learning model to predict the risk of developing hepatocellular carcinoma (HCC) based on the screening results and insurance claim data.

Methods

The National Health Insurance Service-National Health Screening database was used for this study (NHIS-2020-2-146). Our study cohort consisted of 417,346 health screening examinees between 2004 and 2007 without cancer history, which was split into training and test cohorts by the examination date, before or after 2005. Robust predictors were selected using Cox proportional hazard regression with 1000 different bootstrapped datasets. Random forest and extreme gradient boosting algorithms were used to develop a prediction model for the 9-year risk of HCC development after screening. After optimizing a prediction model via cross validation in the training cohort, the model was validated in the test cohort.

Results

Of the total examinees, 0.5% (1799/331,694) and 0.4% (390/85,652) in the training cohort and the test cohort were diagnosed with HCC, respectively. Of the selected predictors, older age, male sex, obesity, abnormal liver function tests, the family history of chronic liver disease, and underlying chronic liver disease, chronic hepatitis virus or human immunodeficiency virus infection, and diabetes mellitus were associated with increased risk, whereas higher income, elevated total cholesterol, and underlying dyslipidemia or schizophrenic/delusional disorders were associated with decreased risk of HCC development (p < 0.001). In the test, our model showed good discrimination and calibration. The C-index, AUC, and Brier skill score were 0.857, 0.873, and 0.078, respectively.

Conclusions

Machine learning-based model could be used to predict the risk of HCC development based on the health screening examination results and claim data.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08498-w.

Use of hydrochlorothiazide and risk of nonmelanoma skin cancer in Koreans: a retrospective cohort study using administrative healthcare data

BACKGROUND

The incidence of skin cancer is increasing because of the ageing population and ultraviolet exposure, and previous studies have revealed that long-term use of hydrochlorothiazide (HCTZ), an antihypertensive agent, has been associated with an increased risk of nonmelanoma skin cancer (NMSC). However, the association of NMSC and HCTZ within East Asian populations is unclear.

AIM

To investigate the risk of NMSC in Korean subjects using HCTZ.

METHODS

A retrospective cohort study was conducted using the administrative healthcare data. The study enrolled 62 243 patients exposed to HCTZ with a cumulative dose of ≥ 2500 mg and 62 243 unexposed subjects matched 1 : 1 with the patients for age, sex and income level.

RESULTS

There was a significant difference in the cumulative incidence of NMSC between the two groups (log-rank P < 0.01). Cox regression analysis was conducted after adjusting for potential confounders, and showed the risk for NMSC in the group exposed to HCTZ was significantly higher than that of the unexposed group (hazard ratio = 1.48; 95% CI 1.03-2.13). In the subgroup analysis, the oldest age group (≥ 70 years) showed increased cumulative incidence of NMSC with statistical significance compared with the unexposed control group (log-rank P < 0.01).

CONCLUSIONS

In this study, we revealed that the cumulative use of HCTZ (≥ 2500 mg) could increase the risk of NMSC in Koreans, especially the older age group. Thus, HCTZ could be a risk factor for NMSC in East Asian as well as white populations.

Magnetic Hamiltonian parameter estimation using deep learning techniques

Understanding spin textures in magnetic systems is extremely important to the spintronics and it is vital to extrapolate the magnetic Hamiltonian parameters through the experimentally determined spin. It can provide a better complementary link between theories and experimental results. We demonstrate deep learning can quantify the magnetic Hamiltonian from magnetic domain images. To train the deep neural network, we generated domain configurations with Monte Carlo method. The errors from the estimations was analyzed with statistical methods and confirmed the network was successfully trained to relate the Hamiltonian parameters with magnetic structure characteristics. The network was applied to estimate experimentally observed domain images. The results are consistent with the reported results, which verifies the effectiveness of our methods. On the basis of our study, we anticipate that the deep learning techniques make a bridge to connect the experimental and theoretical approaches not only in magnetism but also throughout any scientific research.

Creation of skyrmions in van der Waals ferromagnet Fe3GeTe2 on (Co/Pd) n superlattice

Magnetic skyrmions are topological spin textures, which usually exist in noncentrosymmetric materials where the crystal inversion symmetry breaking generates the so-called Dzyaloshinskii-Moriya interaction. This requirement unfortunately excludes many important magnetic material classes, including the recently found two-dimensional van der Waals (vdW) magnetic materials, which offer unprecedented opportunities for spintronic technology. Using photoemission electron microscopy and Lorentz transmission electron microscopy, we investigated and stabilized Néel-type magnetic skyrmion in vdW ferromagnetic Fe₃GeTe₂ on top of (Co/Pd) _n in which the Fe₃GeTe₂ has a centrosymmetric crystal structure. We demonstrate that the magnetic coupling between the Fe₃GeTe₂ and the (Co/Pd) _n could create skyrmions in Fe₃GeTe₂ without the need of an external magnetic field. Our results open exciting opportunities in spintronic research and the engineering of topologically protected nanoscale features by expanding the group of skyrmion host materials to include these previously unknown vdW magnets.

A population-based epidemiology of Wilson's disease in South Korea between 2010 and 2016

Very few population-based studies have examined the epidemiology of Wilson's disease (WD). We investigated the epidemiology of WD using the National Health Insurance Service (NHIS) database in South Korea. We analyzed not only the statistical variables of WD, but also those of WD-related diseases. WD patients were identified with the relevant International Classification of Diseases-10 code out of 50.5 million people. We used the NHIS database from 2009 to 2016 and analyzed the incidence rate, prevalence, and clinical symptoms of WD. A total of 1,333 patients were identified. The average annual incidence rate was 3.8 per million person-years. The prevalence was 38.7 per million people. The mean diagnostic age was 26.1 ± 17.2 with earlier diagnosis in men (P = 0.0003). Among the patients, 988 (74.1%) had hepatic symptoms, 510 (38.3%) had neurologic symptoms, and 601 (45.1%) had psychiatric symptoms. Before the diagnosis of WD, 350 (26.3%) had neurologic symptoms, and 427 (32%) had psychiatric symptoms. The annual mortality rate was 0.7%. Age, liver cirrhosis, and liver failure correlated with a fatal prognosis (P < 0.05). Many patients showed neurologic and psychiatric symptoms before they were diagnosed with WD. Prognosis correlated with age, liver cirrhosis, and liver failure.

Carbohydrate antigen 19-9 elevation without evidence of malignant or pancreatobiliary diseases

Although carbohydrate antigen 19-9 (CA 19-9) may be elevated in benign diseases, elevated CA 19-9 may cause a fear of cancer and unnecessary follow-up studies. Research on how to approach systematically in this case is very limited. The purpose of this study was to analyze the clinical features and the causes of CA 19-9 elevation without evidence of malignant or pancreatobiliary diseases. We retrospectively reviewed the medical records of patients who had CA 19-9 elevation (≥80 U/mL) and were found to be unrelated to cancer after follow-up. After exclusion, 192 patients were included in this study. The median level of CA 19-9 was 136.5 U/mL. The causes of CA 19-9 elevation were determined in 147 (76.6%) patients, and that was unknown in 45 (23.4%). The estimated causative diseases were hepatic diseases in 63 patients, pulmonary diseases in 32, gynecologic diseases in 38, endocrine diseases in 13, and spleen disease in 1. Of 45 patients with unknown cause, 35 had normalization of CA 19-9 and 10 had persistently elevated CA 19-9. In conclusion, CA 19-9 elevation without malignancies or pancreatobiliary diseases should be systematically evaluated and followed up. We suggest an algorithm to investigate the causes and follow up these patients.

Creation and annihilation of topological meron pairs in in-plane magnetized films

Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in chiral magnet Co₈Zn₉Mn₃ raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii–Moriya interaction.

A meron is one half of a skyrmion but whether a single meron pair can be created and stabilized remains a challenging question. Here, Gao et al. develop a method to create and stabilize individual pairs of merons in a continuous Py film by local vortex imprinting from Co disks.

An innovative magnetic state generator using machine learning techniques

We propose a new efficient algorithm to simulate magnetic structures numerically. It contains a generative model using a complex-valued neural network to generate k-space information. The output information is hermitized and transformed into real-space spin configurations through an inverse fast Fourier transform. The Adam version of stochastic gradient descent is used to minimize the magnetic energy, which is the cost of our algorithm. The algorithm provides the proper ground spin configurations with outstanding performance. In model cases, the algorithm was successfully applied to solve the spin configurations of magnetic chiral structures. The results also showed that a magnetic long-range order could be obtained regardless of the total simulation system size.

Thermostable xylanase derived from Trichoderma citrinoviride increases growth performance and non-starch polysaccharide degradation in broiler chickens

1. The aim of this trial was to determine the optimal supplementation level of a xylanase enzyme from Trichoderma citrinoviride on growth performance, apparent ileal and total tract nutrient retention, intestinal morphology, and intestinal concentration of volatile fatty acids in broiler chickens.2. A total of 600 broiler chickens (Ross 308) of mixed sex were randomly allotted to four treatments, on the basis of similar body weight. The dietary treatments were made from a corn-wheat-soy based diet supplemented with either 0, 3750, 7500, or 11 250 XU/kg xylanase and were fed to 32 d of age.3. A linear response to increasing dietary xylanase was demonstrated for overall weight gain (P < 0.05) and feed conversion ratio (P < 0.05). The apparent total tract digestibility of dry matter and gross energy, and the coefficient of apparent ileal digestibility (CIAD) of N and soluble non-starch polysaccharides were linearly improved when xylanase was added to the diet (P < 0.05). Moreover, a linear increase (P < 0.05) was observed in the CIAD of Arg, Lys, and Try with increasing dietary levels of xylanase.4. The viscosity of digesta in ileum was linearly decreased when dietary xylanase level increased (P < 0.05).5. An increase in villus height of the duodenum and jejunum were observed with increasing dietary levels of xylanase (linear, P < 0.05).6. Overall, the results showed that the effects of dietary xylanase supplementation on broiler performance was determined through effects on nutrient availability and intestinal morphology.

Evaluating Tissue Contrast and Detecting White Matter Injury in the Infant Brain: A Comparison Study of Synthetic Phase-Sensitive Inversion Recovery

BACKGROUND AND PURPOSE

Synthetic MR imaging enables the acquisition of phase-sensitive inversion recovery images. The aim of this study was to compare the image quality of synthetic phase-sensitive inversion recovery with that of other sequences in infants.

MATERIALS AND METHODS

Brain MR imaging with 3D T1-weighted fast-spoiled gradient recalled, synthetic T1WI, and synthetic phase-sensitive inversion recovery of 91 infants was compared. Contrast between unmyelinated WM and myelinated WM and between unmyelinated WM and cortical GM was calculated. Qualitative evaluation of image quality and myelination degree was performed. In infants with punctate white matter injuries, the number of lesions was compared.

RESULTS

The contrast between unmyelinated WM and myelinated WM was higher in synthetic phase-sensitive inversion recovery compared with fast-spoiled gradient recalled or synthetic T1WI (P < .001). Compared with synthetic T1WI, synthetic phase-sensitive inversion recovery showed higher gray-white matter differentiation (P < .001) and myelination degree in the cerebellar peduncle (P < .001). The number of detected punctate white matter injuries decreased with synthetic phase-sensitive inversion recovery compared with fast-spoiled gradient recalled sequences (1.2 ± 3.2 versus 3.4 ± 3.6, P = .001).

CONCLUSIONS

Synthetic phase-sensitive inversion recovery has the potential to improve tissue contrast and image quality in the brain MR imaging of infants. However, we have to be aware that synthetic phase-sensitive inversion recovery has limited value when assessing punctate white matter injuries compared with 3D fast-spoiled gradient recalled imaging.

Combined surgical approach to intralabyrinthine schwannoma

INTRODUCTION

Intralabyrinthine schwannoma (ILS) is a tumor originating from the Schwann cells in the inner ear. Various surgical approaches can be used for the resection of ILS. The aim of this report is to describe a case involving a 60-year-old man who was treated successfully with a combined surgical approach.

CASE REPORT

The patient underwent a combined microscopic (transmastoid labyrinthectomy) and endoscopic procedure for surgical excision of ILS involving the vestibule and the lower half of the cochlear basal turn. The combined surgical technique enabled a complete removal of the ILS without removal of the unaffected cochlea as well as the external auditory canal. Besides additional exclusion of the middle ear, blind-sac closure of the external auditory canal and cavity obliteration were avoided. No postoperative complications were observed.

DISCUSSION

A combined microscopic and endoscopic approach to surgery enables removal of the ILS involving the vestibule and the lower half of the cochlear basal turn while helping to reduce surgical radicality.

A Novel Collateral Imaging Method Derived from Time-Resolved Dynamic Contrast-Enhanced MR Angiography in Acute Ischemic Stroke: A Pilot Study

BACKGROUND AND PURPOSE

Assessment of the collateral status has been emphasized for appropriate treatment decisions in patients with acute ischemic stroke. The purpose of this study was to introduce a multiphase MRA collateral imaging method (collateral map) derived from time-resolved dynamic contrast-enhanced MRA and to verify the value of the multiphase MRA collateral map in acute ischemic stroke by comparing it with the multiphase collateral imaging method (MRP collateral map) derived from dynamic susceptibility contrast-enhanced MR perfusion.

MATERIALS AND METHODS

From a prospectively maintained registry of acute ischemic stroke, MR imaging data of patients with acute ischemic stroke caused by steno-occlusive lesions of the unilateral ICA and/or the M1 segment of the MCA were analyzed. We generated collateral maps using dynamic signals from dynamic contrast-enhanced MRA and DSC-MRP using a Matlab-based in-house program and graded the collateral scores of the multiphase MRA collateral map and the MRP collateral map independently. Interobserver reliabilities and intermethod agreement between both collateral maps for collateral grading were tested.

RESULTS

Seventy-one paired multiphase MRA and MRP collateral maps from 67 patients were analyzed. The interobserver reliabilities for collateral grading using multiphase MRA or MRP collateral maps were excellent (weighted κ = 0.964 and 0.956, respectively). The agreement between both collateral maps was also excellent (weighted κ = 0.884; 95% confidence interval, 0.819-0.949).

CONCLUSIONS

We demonstrated that the dynamic signals of dynamic contrast-enhanced MRA could be used to generate multiphase collateral images and showed the possibility of the multiphase MRA collateral map as a useful collateral imaging method in acute ischemic stroke.

Staged partial hepatectomy versus transarterial chemoembolization for the treatment of spontaneous hepatocellular carcinoma rupture: a multicenter analysis in Korea

Purpose

The aim of this study was to identify the prognostic factors and compare the long-term outcomes of staged hepatectomy and transarterial chemoembolization (TACE) for patients with spontaneous rupture of hepatocellular carcinoma (HCC).

Methods

This study is a multicenter, retrospective analysis of patients with newly diagnosed ruptured HCC. To compare overall survival between staged hepatectomy group and TACE alone group, we performed propensity score-matching to adjust for significant differences in patient characteristics. To identify prognostic factors, the clinical characteristics at the time of diagnosis of tumor rupture were investigated using Cox-regression analysis.

Results

From 2000 to 2014, 172 consecutive patients with newly diagnosed ruptured HCC were treated in 6 Korean centers. One hundred seventeen patients with Child-Pugh class A disease were identified; of which 112 were initially treated with transcatheter arterial embolization (TAE) for hemostasis and five underwent emergency surgery for bleeder ligation. Of the 112 patients treated with TAE, 44 underwent staged hepatectomy, 61 received TACE alone, and 7 received conservative treatment after TAE. Those that underwent staged hepatectomy had significantly higher overall survival than those that underwent TACE alone before matching (P < 0.001) and after propensity score-matching (P = 0.006). Multivariate analysis showed that type of treatment, presence of portal vein thrombosis, pretreatment transfusion >1,200 mL, and tumor size >5 cm were associated with poor overall survival.

Conclusion

Staged hepatectomy may offer better long-term survival than TACE alone for spontaneous rupture of HCC. Staged hepatectomy should be considered in spontaneous rupture of HCC with resectable tumor and preserved liver function.

Effect of Annealing Temperature on Morphology and Electrical Property of Hydrothermally-Grown ZnO Nanorods/p-Si Heterojunction Diodes

In this study, ZnO nanorods (NRs) were synthesized using the hydrothermal method, and the effects of annealing temperature (150 °C-600 °C) on morphology, crystallinity, defects states of the NRs, and electrical property of the n-type ZnO NRs/p-type Si heterojunction diodes were investigated. No appreciable changes in the morphology and crystal structure of the ZnO NRs were observed with increasing annealing temperature up to 450 °C. As the temperature increased to 600 °C, the average length and diameter of the NRs decreased due to the partial melting and sintering in the NRs. From the X-ray photoelectron spectroscopy (XPS) results, the concentration of internal oxygen vacancies decreased with increasing annealing temperature to 450 °C due to thermal diffusion of oxygen vacancies to the surface. The electrical conductivity of the NRs increased to 450 °C, which was attributed to the increased crystallinity and low defects concentration (oxygen vacancy) in the NRs. Conversely, the electrical conductivity degraded at 600 °C due to the decreased effective contact area.

Genetic variants and risk of prostate cancer using pathway analysis of a genome-wide association study

This study explored candidate causal single nucleotide polymorphisms (SNPs) to clarify the biological mechanism of prostate cancer (PCa). Identify candidate Causal SNPs and Pathways (ICSNPathway) analysis was applied using a PCa genome-wide association study (GWAS) dataset that included 473,736 SNPs in 1151 cases of PCa and 1156 controls of European ancestry. Five candidate causal SNPs, three candidate causal genes, and two candidate causal pathways were identified using integrating linkage disequilibrium analysis, functional SNP annotation, and pathway-based analysis. The ICSNPathway analysis suggested three hypothetical mechanisms of PCa. The first was rs13112390, rs13112358, rs2048074 to nei-like DNA glycosylase 3 (NEIL3) gene to damaged DNA binding. The second was rs3087386 to REV1, DNA directed polymerase (REV1) gene to damaged DNA binding. The third was rs1063134 to potassium channel, inwardly rectifying subfamily J, member 4 (KCNJ4) gene to inward rectifier potassium channel activity.

Multidelay Arterial Spin-Labeling MRI in Neonates and Infants: Cerebral Perfusion Changes during Brain Maturation

BACKGROUND AND PURPOSE

Arterial spin-labeling with multiple postlabeling delays can correct transit times. We tried to evaluate CBF in neonates and infants using multidelay arterial spin-labeling.

MATERIALS AND METHODS

Multidelay arterial spin-labeling was applied to 13 preterm neonates (mean postmenstrual age, 34.9 weeks), 13 term-equivalent-age neonates (mean postmenstrual age, 39.2 weeks), and 6 infants (mean postmenstrual age, 57.8 weeks). Transit time-corrected CBF in the caudate, thalamus, frontal GM, occipital GM, frontal WM, and occipital WM was measured, and relative CBF compared with the whole-brain CBF was calculated. Inter- and intragroup comparisons were performed among the 3 age groups. A correlation and nonlinear regression analysis were performed between postmenstrual age and CBF.

RESULTS

Intergroup comparisons showed significantly higher whole-brain CBF in infants (38.3 mL/100 g/min) compared with preterm (15.5 mL/100 g/min) and term-equivalent-age (18.3 mL/100 g/min) neonates (P < .001). In the intragroup comparison, all 3 groups showed significantly higher relative CBF values in the occipital WM (63.6%-90.3%) compared with the frontal WM (46.3%-73.9%). In term-equivalent-age neonates, the occipital GM (120.8%) had significantly higher relative CBF values than the frontal GM (103.5%). There was a significant negative correlation between postmenstrual age and the relative CBF of the thalamus (r = - 0.449, P = .010). There were significant positive relationships between postmenstrual age and the relative CBF of the frontal WM (R ² = 0.298, P = .001) and occipital WM (R ² = 0.452, P < .001).

CONCLUSIONS

Multidelay arterial spin-labeling with transit time-corrected CBF showed developmental changes and regional differences of CBF in neonates and infants.

Facet Control of Subunits in Anatase TiO₂ Mesocrystal by Diethanolamine for Enhanced Photocatalytic Activity

Controllable TiO2 architectures with different facets play a key role in the adjustment of the surface area and charge recombination efficiency in photocatalysts. In this study, we synthesized anatase TiO2 mesocrystals with diethanolamine (DEA, 0-5 mM) as a nontoxic capping agent to control the facet of subunits using hydrothermal method, and determine the effect of DEA on subunits, by-products, and consequent photocatalytic performance of TiO2 mesocrystals. The pure TiO2 was spindle-like shaped mesocrystal having bipyramidal subunits with high portion of {101} facets. As DEA concentration was increased, the percentage of {001} exposed facet of subunits increased, but the number of subunits was gradually reduced. When a large amount of DEA (≥3 mM) was added, TiO2 exhibited single crystals rather than mesocrystal, probably because the long chain of DEA interfered with the oriented attachment of subunits. The photocatalytic activity of the TiO2 improved at 0.5 mM of DEA due to low charge recombination rate by increasing {001} facet. On the other hand, subsequent deterioration with further increase of DEA was attributed to the increased by-products and reduced the number of subunits despite the increase in specific surface area. These results imply that charge separation efficiency, rather than specific surface area, is highly responsible for the photocatalytic activity of TiO2.

Real World Experience of Telbivudine Versus Entecavir in Patients with Chronic Hepatitis B, Including Long-Term Outcomes after Treatment Modification

PURPOSE

To estimate long-term outcomes after treatment modification in patients with chronic hepatitis B (CHB) treated with entecavir (ETV) and telbivudine (LdT).

MATERIALS AND METHODS

The study enrolled 131 nucleos(t)ide analogue (NA)-naïve CHB patients treated with ETV or LdT. During the 3-year study, NA treatment history including the incidence, the type of treatment modification, reasons for the modification, and overall complete virologic response (CVR) rate were retrospectively evaluated using the patients' medical records.

RESULTS

Among the 131 patients, 84 and 47 were initially treated with ETV and LdT, respectively. During the course of 3-year study, 82 patients in the ETV group (97.6%) maintained initial treatment whereas only 19 in the LdT group (40.4%). In the LdT group, 26 patients (92.9%) switched to another NA and another NA was added in 2 (7.1%) patients. An assessment of the CVR rate at 3 years, including treatment modification, showed that 89.3% and 95.7% of patients in the ETV and LdT groups, respectively, had undetectable serum hepatitis B virus DNA levels (p=0.329). Among LdT patients with treatment modification, the cumulative incidence rate of a CVR for rescue therapy was significantly higher in the tenofovir than in the ETV group (p=0.009).

CONCLUSION

During the 3-year study, there were no significant differences in the CVR between the ETV and LdT groups if appropriate rescue therapy was considered.

UFD1 contributes to MYC-mediated leukemia aggressiveness through suppression of the proapoptotic unfolded protein response

Despite the pivotal role of MYC in tumorigenesis, the mechanisms by which it promotes cancer aggressiveness remain incompletely understood. Here we show that MYC transcriptionally upregulates the ubiquitin fusion degradation 1 (UFD1) gene in T-cell acute lymphoblastic leukemia (T-ALL). Allelic loss of ufd1 in zebrafish induces tumor-cell apoptosis and impairs MYC-driven T-ALL progression but does not affect general health. As the E2 component of an endoplasmic reticulum (ER)-associated degradation (ERAD) complex, UFD1 facilitates the elimination of misfolded/unfolded proteins from the ER. We found that UFD1 inactivation in human T-ALL cells impairs ERAD, exacerbates ER stress, and induces apoptosis. Moreover, we show that UFD1 inactivation promotes the proapoptotic unfolded protein response (UPR) mediated by protein kinase RNA-like ER kinase (PERK). This effect is demonstrated by an upregulation of PERK and its downstream effector C/EBP homologous protein (CHOP), as well as a downregulation of BCL2 and BCLxL. Indeed, CHOP inactivation or BCL2 overexpression is sufficient to rescue tumor-cell apoptosis induced by UFD1 knockdown. Together, our studies identify UFD1 as a critical regulator of the ER stress response and a novel contributor to MYC-mediated leukemia aggressiveness, with implications for targeted therapy in T-ALL and likely other MYC-driven cancers.

The spin structures of interlayer coupled magnetic films with opposite chirality

Using Monte-Carlo simulations and micromagnetic simulations, we reveal how the spin structural correlation and the skyrmion dynamics are affected by the interlayer coupling in a chiral magnetic bilayer system, in which the two layers have opposite chirality. The interaction through interlayer coupling between chiral magnetic structures influences the static and dynamics properties profoundly. The competition between the Dzyaloshinskii-Moriya interaction and the interlayer interaction allows multiple magnetic structures to be energetically stable, which includes sole skyrmion states (skyrmion appears in only one of the layers) and skyrmion pair states (coupled skyrmions in top and bottom layers). When current driven spin transfer torques are applied to each state, the sole skyrmion state is mainly propelled by a spin transfer torque causing the skyrmion hall effect, but the skyrmion pair state is propelled by a torque from skyrmion-skyrmion interaction and not influenced by the skyrmion hall effect. Also upon application of an external magnetic field, we found the skyrmions in a skyrmion pair state extinguish in an exclusive way, as the annihilation of a skyrmion in one of the layers stabilizes the once paired skyrmion in the other layer, i.e. the skyrmion lattice sites have only one skyrmion in either layer.

Melanoma of the Sinonasal Tract: Value of a Septate Pattern on Precontrast T1-Weighted MR Imaging

BACKGROUND AND PURPOSE

Various tumors of the sinonasal tract can exhibit high signal intensity on T1WI. The purpose of this study was to determine the value of a septate pattern on precontrast T1WI for diagnosing sinonasal melanoma.

MATERIALS AND METHODS

Retrospectively, 3 observers independently reviewed MR images of 31 histologically proved sinonasal melanomas with special attention to the presence or absence of a septate pattern on precontrast T1WI, defined as alternating hyperintense and hypointense striations on precontrast T1WI. For comparison, we evaluated the prevalence of a septate pattern on precontrast T1WI in 106 nonmelanomatous sinonasal malignant tumors with 16 different histologic types. We also tried to identify the histopathologic features responsible for the septate pattern on precontrast T1WI.

RESULTS

Twenty-seven (87.1%) of 31 sinonasal melanomas showed hyperintense foci on T1WI, among which a septate pattern on precontrast T1WI was seen in 23 (74.2%), while 22 (20.8%) of 106 nonmelanomatous malignant tumors demonstrated hyperintense foci on T1WI, among which only 3 (2.8%) showed a septate pattern on precontrast T1WI. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of a septate pattern on precontrast T1WI for the diagnosis of sinonasal melanoma were 74%, 97%, 88%, 93%, and 92%, respectively. Although limited due to the retrospective nature, 4 of 23 histologically reviewed sinonasal melanomas revealed an uneven distribution of melanin with alternating melanin and fibrous bands within the tumors.

CONCLUSIONS

A septate pattern on precontrast T1WI might be an adjunctive imaging finding for the diagnosis of sinonasal melanoma. This might be attributed histologically to an uneven distribution of melanin and hemorrhage within the tumors.

Appropriate Minimal Dose of Gadobutrol for 3D Time-Resolved MRA of the Supra-Aortic Arteries: Comparison with Conventional Single-Phase High-Resolution 3D Contrast-Enhanced MRA

BACKGROUND AND PURPOSE

The development of nephrogenic systemic fibrosis and neural tissue deposition is gadolinium dose-dependent. The purpose of this study was to determine the appropriate minimal dose of gadobutrol with time-resolved MRA to assess supra-aortic arterial stenosis with contrast-enhanced MRA as a reference standard.

MATERIALS AND METHODS

Four hundred sixty-two consecutive patients underwent both standard-dose contrast-enhanced MRA and low-dose time-resolved MRA and were classified into 3 groups; group A (a constant dose of 1 mL for time-resolved MRA), group B (2 mL), or group C (3 mL). All studies were independently evaluated by 2 radiologists for image quality by using a 5-point scale (from 0 = failure to 4 = excellent), grading of arterial stenosis (0 = normal, 1 = mild [<30%], 2 = moderate [30%-69%], 3 = severe to occlusion [≥70%]), and signal-to-noise ratio.

RESULTS

The image quality of time-resolved MRA was similar to that of contrast-enhanced MRA in groups B and C, but it was inferior to contrast-enhanced MRA in group A. For the grading of arterial stenosis, there was an excellent correlation between contrast-enhanced MRA and time-resolved MRA (R = 0.957 for group A, R = 0.988 for group B, R = 0.991 for group C). The SNR of time-resolved MRA tended to be lower than that of contrast-enhanced MRA in groups A and B. However, SNR was higher for time-resolved MRA compared with contrast-enhanced MRA in group C.

CONCLUSIONS

Low-dose time-resolved MRA is feasible in the evaluation of supra-aortic stenosis and could be used as an alternative to contrast-enhanced MRA for a diagnostic technique in high-risk populations.

Aminophylline Effect on Renal Ischemia-Reperfusion Injury in Mice

BACKGROUND

Aminophylline increases the intracellular concentration of cAMP and exerts an anti-inflammatory effect. The aim of this study was to investigate the effect of aminophylline on renal ischemia-reperfusion (I/R) injury in mice.

METHODS

Thirty C57BL/6 mice were divided into 3 groups. In the sham group (group S, n = 10), only right nephrectomy was performed. In the control group (group C, n = 10), after right nephrectomy, the mice were subjected to 30 minutes of left renal ischemia. In the aminophylline group (group A, n = 10), an intraperitoneal injection of aminophylline (5 mg/kg) was performed before renal ischemia. Twenty-four hours after reperfusion, the mice were euthanized, and plasma and kidney samples were obtained to analyze the serum creatinine, renal histology, and expression levels of nuclear factor-kappa B (NF-kB) and pro-inflammatory cytokines.

RESULTS

The serum creatinine concentration in group C was markedly elevated at 24 hours after reperfusion. Aminophylline treatment significantly reduced serum creatinine, compared with group C. Aminophylline also reduced the histological evidence of renal damage. The expression levels of NF-kB, tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-2 (MIP-2), and intercellular adhesion molecule-1 (ICAM-1) mRNA were significantly increased in group C (P < .001). Group A showed lower expression of NF-kB, TNF-α, MCP-1, MIP-2, and ICAM-1 mRNA than group C (P < .01).

CONCLUSIONS

Aminophylline treatment improved the renal function and indexes of renal inflammation, which suggests that it provided reno-protection against renal I/R injury.

Entecavir to Telbivudine Switch Therapy in Entecavir-Treated Patients with Undetectable Hepatitis B Viral DNA

PURPOSE

This study examined 2-year outcome of consecutive therapy using entecavir (ETV) followed by telbivudine (LdT) in subjects with undetectable hepatitis B virus (HBV) DNA level and normal alanine aminotransferase level after the initial 6 months of ETV treatment.

MATERIALS AND METHODS

Sixty subjects were randomized to continue with ETV or switch to LdT. Significant difference in baseline characteristics was not found between the two groups. Persistent HBV DNA level of 20-60 IU/mL in three consecutive samples collected three months apart or singly measured HBV DNA level of >60 IU/mL was defined as virological rebound.

RESULTS

During 96 weeks of follow-up, all subjects of the ETV-only group (n=30) resulted in undetectable HBV DNA level. On the other hand, 83.3% (n=25) of the LdT-switched group showed treatment success. Virological rebound time varied from week 24 to 84 after switching to LdT. HBV DNA level was 180 to 2940 IU/mL at rebound time. All subjects with virological rebound (n=5) showed drug-resistant mutation: three had mutation rtM204I, and two had mutation rtM204V. Consecutive treatment using ETV followed by LdT showed virological rebound in 16.7% of subjects during 96 weeks of follow-up. HBV DNA negativity during initial ETV therapy could not be achieved in patients who switched to LdT.

CONCLUSION

Consecutive treatment using ETV followed by lamivudine was ineffective for treating chronic hepatitis B. LdT was found as a more potent antiviral agent than lamivudine. However, this conclusion requires larger-scale, long-term prospective reviews of the treatment effects of ETV-LdT switch therapy.

Intratumoural heterogeneity measured using FDG PET and MRI is associated with tumour-stroma ratio and clinical outcome in head and neck squamous cell carcinoma

AIM

To evaluate the association between the tumour-stroma ratio and intratumoural heterogeneity measured using 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) and magnetic resonance imaging (MRI), and further investigate the prognostic significance of imaging biomarkers in head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

Textural-based imaging parameters of the primary tumour were extracted in 44 patients. In addition, the difference between the minimum and maximum apparent diffusion coefficient (ADC) values (ADCdiff) was calculated on MRI. The relationships between the tumour-stroma ratio and imaging parameters were evaluated. The associations between imaging parameters and recurrence-free survival (RFS) were assessed using Cox proportional hazard regression models.

RESULTS

Coarseness (r=-0.382) on PET and ADCdiff (r=0.534) on MRI were significantly correlated with the proportion of stroma. The best imaging biomarkers for the 2-year RFS prediction were coarseness (AUC=0.741) and ADCdiff (AUC=0.779). Multivariate analysis showed that coarseness (hazard ratio=10.549, 95% confidence interval=2.544-43.748, p=0.001) was an independent prognostic factor for RFS.

CONCLUSION

Heterogeneity imaging parameters are significantly associated with the tumour-stroma ratio. These imaging biomarkers may help to facilitate the risk stratification for tumour recurrence in HNSCC.

Anti-nociceptive and anti-inflammatory effects of the methanolic extract of Opuntia humifusa stem

OBJECTIVE

Opuntia humifusa (O. humifusa) Raf. has been used for the prevention and treatment of rheumatoid arthritis, inflammation, and cancer. Our study was designed to unveil the anti-nociceptive and anti-inflammatory effects of the methanolic extract of O. humifusa Raf stem (OHS).

MATERIALS AND METHODS

The anti-nociceptive effect was measured by hot plate, acetic acid-induced writhing, and tail flick assays in mice and rats. Moreover, the anti-inflammatory effect was measured by vascular permeability and carrageenan and serotonin-induced paw edema tests in rats. Furthermore, anti-inflammatory effect was also measured using macrophage-like LPS-induced RAW 264.7 cells.

RESULTS

OHS extract inhibited acetic acid-induced writhing (p<0.0001), and delayed the reaction time of mice to the hot plate-induced thermal stimulation (p<0.0001) and tail flick tests (p<0.05). OHS extract attenuated the carrageenan and serotonin-induced paw edema in rats (p<0.001). Similarly, OHS extract significantly decreased Evans blue concentration in acetic acid induced vascular permeability test (p<0.0001), revealing its strong anti-inflammatory effect. Finally, among four different fractions of OHS extract, n-butanol fraction strongly decreased NO production (p<0.0001) and iNOS expression in LPS-induced RAW 264.7 cells.

CONCLUSION

Our results suggest that the methanolic extract of O. humifusa stem can be used to develop a therapeutic or supportive drug and/or functional food against pain and inflammation related diseases.

Advanced remediation of uranium-contaminated soil

The existing decontamination method using electrokinetic equipment after acidic washing for uranium-contaminated soil requires a long decontamination time and a significant amount of electric power. However, after soil washing, with a sulfuric acid solution and an oxidant at 65 °C, the removal of the muddy solution using a 100 mesh sieve can decrease the radioactivity of the remaining coarse soil to the clearance level. Therefore, only a small amount of fine soil collected from the muddy solution requires the electrokinetic process for its decontamination. Furthermore, it is found that the selective removal of uranium from the sulfuric washing solution is not obtained using an anion exchanger but rather using a cation exchanger, unexpectedly. More than 90% of the uranium in the soil washing solutions is adsorbed on the S-950 resin, and 87% of the uranium adsorbed on S-950 is desorbed by washing with a 0.5 M Na₂CO₃ solution at 60 °C.

Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak in South Korea, 2015: epidemiology, characteristics and public health implications

Background

Since the first case of Middle East respiratory syndrome coronavirus (MERS-CoV) in South Korea was reported on 20^th May 2015, there have been 186 confirmed cases, 38 deaths and 16,752 suspected cases. Previously published research on South Korea's MERS outbreak was limited to the early stages, when few data were available. Now that the outbreak has ended, albeit unofficially, a more comprehensive review is appropriate.

Methods

Data were obtained through the MERS portal by the Ministry for Health and Welfare (MOHW) and Korea Centres for Disease Control and Prevention, press releases by MOHW, and reports by the MERS Policy Committee of the Korean Medical Association. Cases were analysed for general characteristics, exposure source, timeline and infection generation. Sex, age and underlying diseases were analysed for the 38 deaths.

Findings

Beginning with the index case that infected 28 others, an in-depth analysis was conducted. The average age was 55 years, which was a little higher than the global average of 50 years. As in most other countries, more men than women were affected. The case fatality rate was 19.9%, which was lower than the global rate of 38.7% and the rate in Saudi Arabia (36.5%). In total, 184 patients were infected nosocomially and there were no community-acquired infections. The main underlying diseases were respiratory diseases, cancer and hypertension. The main contributors to the outbreak were late diagnosis, quarantine failure of ‘super spreaders’, familial care-giving and visiting, non-disclosure by patients, poor communication by the South Korean Government, inadequate hospital infection management, and ‘doctor shopping’. The outbreak was entirely nosocomial, and was largely attributable to infection management and policy failures, rather than biomedical factors.

Estimation of direct medical cost related to the management of chronic hepatitis C and its complications in South Korea

BACKGROUND

This study aimed to estimate the direct medical costs of managing chronic hepatitis C (CHC) and its complications based on health-care resources in South Korea.

METHODS

The study design was multicenter, retrospective, non-interventional, and observational. Between September 2013 and April 2014, health-care resource data from patients chronically infected with hepatitis C virus, regardless of genotype, were collected from 8 institutions, including data related to outpatient management, emergency care, and hospitalization. The observation period was between January 2011 and December 2012. The disease state was classified as CHC, compensated cirrhosis (CC), decompensated cirrhosis (DC), or hepatocellular carcinoma (HCC).

RESULTS

A total of 445 patients were recruited and mean age was 60.1 ± 12.3 years. Among 155 patients with reported outcomes of antiviral therapy, 107 (69%) had sustained virologic response (SVR). The rate of patients who did not receive antiviral therapy was 52.8% (n = 235). The distribution of disease state was CHC in 307 patients (69.0%), CC in 75 (16.9%), HCC in 45 (10.1%), and DC in 18 (4.0%). All direct medical costs, whether reimbursed or nonreimbursed by the National Health Insurance System, were included. After excluding patients whose observational period was <1 month for each disease status, the mean costs per month increased as disease state progressed (CHC: 77 ± 80 USD; CC: 98 ± 94 USD; DC: 512 ± 1115 USD; HCC: 504 ± 717 USD). The mean total costs per person were 3590 ± 8783 USD, and approximately 72% of patients were reimbursed. When 44 patients with an observation period <1 month were excluded, the mean medical costs per month for patients with CHC who achieved SVR (n = 69) were significantly lower than for those (n = 215) who did not (42 ± 16 vs 79 ± 83 USD, P < 0.001). The cost also tended to be lower for patients with CC with SVR (n = 8) than for those without SVR (n = 70; 48 ± 20 vs 95 ± 96 USD, P = 0.177). The cost of antiviral therapy (pegylated interferon and ribavirin) corresponded to 19.0% of total medical costs and 53.7% of prescription/pharmacy.

CONCLUSION

The direct medical costs increased as disease state progressed from CHC to cirrhosis or HCC. The achievement of SVR by antiviral therapy would decrease the costs.

Effect of Intracranial Atherosclerotic Disease on Endovascular Treatment for Patients with Acute Vertebrobasilar Occlusion

BACKGROUND AND PURPOSE

Although intracranial atherosclerotic disease is often encountered during endovascular treatment for acute vertebrobasilar occlusions, its clinical implication is not well-known. We aimed to evaluate whether intracranial atherosclerotic disease influences the clinical outcomes following endovascular treatment of acute vertebrobasilar occlusive stroke.

MATERIALS AND METHODS

Fifty-one patients with acute vertebrobasilar occlusive stroke were included. The onset-to-groin puncture time was ≤12 hours, and aspiration- or stent-based thrombectomy was used as the primary treatment method. Following primary endovascular treatment, intracranial atherosclerotic disease (IAD group) was angiographically diagnosed when a fixed focal stenosis was observed at the occlusion site, whereas embolism (embolic group) was diagnosed if no stenosis was observed. Clinical and treatment variables were compared in both groups, and IAD was evaluated as a prognostic factor for clinical outcomes.

RESULTS

The baseline NIHSS score tended to be lower (14 versus 22, P = .097) in the IAD group (n = 19) than in the embolic group (n = 32). The procedural time was longer in the IAD group (96 versus 61 minutes, P = .002), despite similar rates of TICI 2b-3 (89.5% versus 87.5%, P = 1.000). The NIHSS score at 7 days was higher (21 versus 8, P = .060) and poor outcomes (mRS 4-6 at 3 months) were more frequent in the IAD group (73.7% versus 43.8%, P = .038). IAD (odds ratio, 5.469; 95% CI, 1.09-27.58; P = .040) was independently associated with poor outcomes.

CONCLUSIONS

An arterial occlusion related to IAD was associated with a longer procedural time and poorer clinical outcome. Further studies are warranted to elucidate the appropriate endovascular strategy.