Developing and Validating a Korean Version of the Assessment of Children's Emotional Skills

In this study, a Korean Assessment of Children's Emotional Skills (ACES) was developed by modifying the original ACES which was initially introduced in the United States. Specifically, the original ACES was translated into Korean and revised to better fit the Korean cultural context. The content validity of the revised Korean ACES was established via expert reviews. To test its reliability, the revised Korean ACES was conducted on 286 six-year-old children. A confirmatory factor analysis indicated that our newly developed Korean ACES can be used as an appropriate tool to measure Korean children's emotional skills. The Korean ACES can stimulate further studies on these emotional skills and contribute to various international collaborative studies that seek to compare the emotional skills of children from diverse cultural backgrounds.

Simulation Method for the Physical Deformation of a Three-Dimensional Soft Body in Augmented Reality-Based External Ventricular Drainage

OBJECTIVES

Intraoperative navigation reduces the risk of major complications and increases the likelihood of optimal surgical outcomes. This paper presents an augmented reality (AR)-based simulation technique for ventriculostomy that visualizes brain deformations caused by the movements of a surgical instrument in a three-dimensional brain model. This is achieved by utilizing a position-based dynamics (PBD) physical deformation method on a preoperative brain image.

METHODS

An infrared camera-based AR surgical environment aligns the real-world space with a virtual space and tracks the surgical instruments. For a realistic representation and reduced simulation computation load, a hybrid geometric model is employed, which combines a high-resolution mesh model and a multiresolution tetrahedron model. Collision handling is executed when a collision between the brain and surgical instrument is detected. Constraints are used to preserve the properties of the soft body and ensure stable deformation.

RESULTS

The experiment was conducted once in a phantom environment and once in an actual surgical environment. The tasks of inserting the surgical instrument into the ventricle using only the navigation information presented through the smart glasses and verifying the drainage of cerebrospinal fluid were evaluated. These tasks were successfully completed, as indicated by the drainage, and the deformation simulation speed averaged 18.78 fps.

CONCLUSIONS

This experiment confirmed that the AR-based method for external ventricular drain surgery was beneficial to clinicians.

Theory of transition from brittle to ductile fracture

In this paper, two improvements to the theory of transition from brittle to ductile fracture developed by Langer [J. S. Langer, Phys. Rev. E 103, 063004 (2021)2470-004510.1103/PhysRevE.103.063004] are proposed. First, considering the drastic temperature rise near the crack tip, the temperature dependence of the shear modulus is included to better quantify the thermally sensitive dislocation entanglement. Second, the parameters of the improved theory are identified by the large-scale least-squares method. The comparison between the fracture toughness predicted by the theory and the values obtained in Gumbsch's experiments for tungsten at different temperatures [P. Gumbsch et al., Science 282, 1293 (1998)10.1126/science.282.5392.1293] shows good agreement.

Non-rigid registration based on hierarchical deformation of coronary arteries in CCTA images

In this paper, we propose an accurate and rapid non-rigid registration method between blood vessels in temporal 3D cardiac computed tomography angiography images of the same patient. This method provides auxiliary information that can be utilized in the diagnosis and treatment of coronary artery diseases. The proposed method consists of the following four steps. First, global registration is conducted through rigid registration between the 3D vessel centerlines obtained from temporal 3D cardiac CT angiography images. Second, point matching between the 3D vessel centerlines in the rigid registration results is performed, and the corresponding points are defined. Third, the outliers in the matched corresponding points are removed by using various information such as thickness and gradient of the vessels. Finally, non-rigid registration is conducted for hierarchical local transformation using an energy function. The experiment results show that the average registration error of the proposed method is 0.987 mm, and the average execution time is 2.137 s, indicating that the registration is accurate and rapid. The proposed method that enables rapid and accurate registration by using the information on blood vessel characteristics in temporal CTA images of the same patient.

Impact of Baseline Muscle Mass and Myosteatosis on the Development of Early Toxicity During First-Line Chemotherapy in Patients With Initially Metastatic Pancreatic Cancer

Objectives

Although chemotherapy is the only treatment option for metastatic pancreatic cancer (PDAC), patients frequently encounter adverse events during chemotherapy leading deterioration of patients’ quality of life and treatment interruption. We evaluated the role of baseline CT-assessed body composition in predicting early toxicity during first cycle of the first-line chemotherapy in patients with metastatic PDAC.

Methods

This retrospective study included 636 patients with initially metastatic PDAC who underwent first-line chemotherapy from January 2009 to December 2019. Chemotherapy regimen, baseline laboratory data, and body composition parameters acquired from baseline CT were obtained. The skeletal muscle index (SMI) was used to identify patients with a low muscle mass (SMI < 41 cm2/m2 for women, and < 43 cm2/m2 [body mass index < 25 cm/kg2] or < 53 cm2/m2 [body mass index ≥ 25 cm/kg2] for men), and myosteatosis was defined as low-attenuated muscle area divided by skeletal muscle area (LAMA/SMA index) ≥ 20%. Univariate and multivariable binary logistic regression analyses were performed using bootstrapping with 500 interactions to identify predictors of grade 3–4 toxicity and any treatment-modifying toxicity which led to a dose reduction, delayed administration, drug skip or discontinuation.

Results

During the first cycle of the first-line chemotherapy, grade 3–4 toxicity and treatment-modifying toxicity occurred in 160 patients (25.2%) and in 247 patients (38.8%), respectively. The presence of both low muscle mass and myosteatosis was significantly associated with the occurrence of both grade 3-4 toxicity (odd ratio [OR], 1.73; 95% confidence interval [CI], 1.14–2.63) and treatment-modifying toxicity (OR, 1.83; 95% CI, 1.26–2.66) whereas low muscle mass alone did not.

Conclusions

The presence of both low muscle mass and myosteatosis assessed on baseline CT may be used to predict early chemotherapy-related toxicity in patients with metastatic PDAC.

Development of a fully automatic deep learning system for L3 selection and body composition assessment on computed tomography

As sarcopenia research has been gaining emphasis, the need for quantification of abdominal muscle on computed tomography (CT) is increasing. Thus, a fully automated system to select L3 slice and segment muscle in an end-to-end manner is demanded. We aimed to develop a deep learning model (DLM) to select the L3 slice with consideration of anatomic variations and to segment cross-sectional areas (CSAs) of abdominal muscle and fat. Our DLM, named L3SEG-net, was composed of a YOLOv3-based algorithm for selecting the L3 slice and a fully convolutional network (FCN)-based algorithm for segmentation. The YOLOv3-based algorithm was developed via supervised learning using a training dataset (n = 922), and the FCN-based algorithm was transferred from prior work. Our L3SEG-net was validated with internal (n = 496) and external validation (n = 586) datasets. Ground truth L3 level CT slice and anatomic variation were identified by a board-certified radiologist. L3 slice selection accuracy was evaluated by the distance difference between ground truths and DLM-derived results. Technical success for L3 slice selection was defined when the distance difference was < 10 mm. Overall segmentation accuracy was evaluated by CSA error and DSC value. The influence of anatomic variations on DLM performance was evaluated. In the internal and external validation datasets, the accuracy of automatic L3 slice selection was high, with mean distance differences of 3.7 ± 8.4 mm and 4.1 ± 8.3 mm, respectively, and with technical success rates of 93.1% and 92.3%, respectively. However, in the subgroup analysis of anatomic variations, the L3 slice selection accuracy decreased, with distance differences of 12.4 ± 15.4 mm and 12.1 ± 14.6 mm, respectively, and with technical success rates of 67.2% and 67.9%, respectively. The overall segmentation accuracy of abdominal muscle areas was excellent regardless of anatomic variation, with CSA errors of 1.38-3.10 cm². A fully automatic system was developed for the selection of an exact axial CT slice at the L3 vertebral level and the segmentation of abdominal muscle areas.

Visceral adiposity as a risk factor for lean non-alcoholic fatty liver disease in potential living liver donors

BACKGROUND AND AIM

This study aimed to investigate the relationship between hepatic steatosis (HS) evaluated by biopsy and visceral adiposity assessed by computed tomography in lean living liver donor candidates and to determine the risk factors for lean non-alcoholic fatty liver disease (NAFLD).

METHODS

This retrospective study included 250 lean (body mass index, < 23 kg/m² ) potential living liver donors (mean age, 31.1 ± 8.6 years; 141 men) who had undergone liver biopsy and abdominal computed tomography between 2017 and 2018. Anthropometry, laboratory parameters, body composition, and the degree of HS were evaluated. Logistic regression was used to identify independent predictors of lean NAFLD.

RESULTS

The visceral fat area (VFA) was significantly correlated with the degree of HS in men (r = 0.408; P < 0.001) and women (r = 0.360; P < 0.001). The subcutaneous fat area was significantly correlated with the degree of HS in men (r = 0.398; P < 0.001), but not in women. The skeletal muscle area did not correlate with the degree of HS in either men or women. In the multivariable logistic regression analysis, the VFA (odds ratio [OR], 1.028; 95% confidence interval [CI], 1.013-1.044; P < 0.001) and subcutaneous fat area (OR, 1.016; 95% CI, 1.004-1.028; P = 0.009) were independent risk factors for lean NAFLD in men, and the VFA (OR, 1.036; 95% CI, 1.013-1.059; P = 0.002) was an independent risk factor for lean NAFLD in women.

CONCLUSIONS

The severity of non-alcoholic fatty liver was positively correlated with visceral fat accumulation in a lean Asian population. Visceral adiposity may be a risk factor for lean NAFLD in potential living liver donors.

Capecitabine plus temozolomide in patients with grade 3 unresectable or metastatic gastroenteropancreatic neuroendocrine neoplasms with Ki-67 index <55%: single-arm phase II study

BACKGROUND

Grade 3 neuroendocrine neoplasms (NENs) of gastroenteropancreatic (GEP) origin with Ki-67 indices <55% do not respond well to platinum-based chemotherapy. The combination of capecitabine and temozolomide (CAPTEM) has shown favorable responses in grade 1-2 NENs, but has rarely been studied in patients with grade 3 NENs.

PATIENTS AND METHODS

This open-label, single-arm phase II trial included patients with unresectable or metastatic grade 3 NENs of GEP origin with Ki-67 indices <55% enrolled between June 2017 and July 2020. Patients received oral capecitabine 750 mg/m2 twice daily on days 1 to 14 and oral temozolomide 200 mg/m2 once daily on days 10 to 14 every 4 weeks. Histologic findings were centrally reviewed after the completion of enrollment. The primary endpoint was overall response rate, and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and adverse events.

RESULTS

Of the 30 patients included in the full analysis set, 1 (3.3%) achieved complete response, 8 (26.7%) had partial responses, and 14 (46.7%) had stable disease, making the overall response rate 30.0%. At a median follow-up of 19.2 months, the median PFS was 5.9 months and the median OS was not reached. Patients with well-differentiated NENs showed significantly better median PFS (9.3 months versus 3.5 months, P = 0.005) and median OS (not reached versus 6.2 months, P = 0.004) than patients with poorly differentiated tumors. Expression of O6-methyl-guanine methyltransferase protein did not correlate with clinical outcomes. The most common grade 3-4 adverse events were thrombocytopenia (10%), anemia (6.7%), and nausea (6.7%).

CONCLUSIONS

CAPTEM was effective and well tolerated in patients with grade 3 GEP-NENs with Ki-67 indices <55%, with superior efficacy outcomes compared with the historical controls receiving platinum-based chemotherapy.

Preoperative nutritional risk index and postoperative one-year skeletal muscle loss can predict the prognosis of patients with gastric adenocarcinoma: a registry-based study

Background

Patients with gastric cancer have an increased nutritional risk and experience a significant skeletal muscle loss after surgery. We aimed to determine whether muscle loss during the first postoperative year and preoperative nutritional status are indicators for predicting prognosis.

Methods

From a gastric cancer registry, a total of 958 patients who received curative gastrectomy followed by chemotherapy for stage 2 and 3 gastric cancer and survived longer than 1 year were investigated. Clinical and laboratory data were collected. Skeletal muscle index (SMI) was assessed based on the muscle area at the L3 level on abdominal computed tomography.

Results

Preoperative nutritional risk index (NRI) and postoperative decrement of SMI (dSMI) were significantly associated with overall survival (hazards ratio: 0.976 [95% CI: 0.962–0.991] and 1.060 [95% CI: 1.035–1.085], respectively) in a multivariate Cox regression analysis. Recurrence, tumor stage, comorbidity index were also significant prognostic indicators. Kaplan-Meier analyses exhibited that patients with higher NRI had a significantly longer survival than those with lower NRI (5-year overall survival: 75.8% vs. 63.0%, P <  0.001). In addition, a significantly better prognosis was observed in a patient group with less decrease of SMI (5-year overall survival: 75.7% vs. 66.2%, P = 0.009). A logistic regression analysis demonstrated that the performance of preoperative NRI and dSMI in mortality prediction was quite significant (AUC: 0.63, P <  0.001) and the combination of clinical factors enhanced the predictive accuracy to the AUC of 0.90 (P <  0.001). This prognostic relevance of NRI and dSMI was maintained in patients experiencing tumor recurrence and highlighted in those with stage 3 gastric adenocarcinoma.

Conclusions

Preoperative NRI is a predictor of overall survival in stage 2 or 3 gastric cancer patients and skeletal muscle loss during the first postoperative year was significantly associated with the prognosis regardless of relapse in stage 3 tumors. These factors could be valuable adjuncts for accurate prediction of prognosis in gastric cancer patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07885-7.

Assessment of Myosteatosis on Computed Tomography by Automatic Generation of a Muscle Quality Map Using a Web-Based Toolkit: Feasibility Study

Background

Muscle quality is associated with fatty degeneration or infiltration of the muscle, which may be associated with decreased muscle function and increased disability.

Objective

The aim of this study is to evaluate the feasibility of automated quantitative measurements of the skeletal muscle on computed tomography (CT) images to assess normal-attenuation muscle and myosteatosis.

Methods

We developed a web-based toolkit to generate a muscle quality map by categorizing muscle components. First, automatic segmentation of the total abdominal muscle area (TAMA), visceral fat area, and subcutaneous fat area was performed using a predeveloped deep learning model on a single axial CT image at the L3 vertebral level. Second, the Hounsfield unit of each pixel in the TAMA was measured and categorized into 3 components: normal-attenuation muscle area (NAMA), low-attenuation muscle area (LAMA), and inter/intramuscular adipose tissue (IMAT) area. The myosteatosis area was derived by adding the LAMA and IMAT area. We tested the feasibility of the toolkit using randomly selected healthy participants, comprising 6 different age groups (20 to 79 years). With stratification by sex, these indices were compared between age groups using 1-way analysis of variance (ANOVA). Correlations between the myosteatosis area or muscle densities and fat areas were analyzed using Pearson correlation coefficient r.

Results

A total of 240 healthy participants (135 men and 105 women) with 40 participants per age group were included in the study. In the 1-way ANOVA, the NAMA, LAMA, and IMAT were significantly different between the age groups in both male and female participants (P≤.004), whereas the TAMA showed a significant difference only in male participants (male, P<.001; female, P=.88). The myosteatosis area had a strong negative correlation with muscle densities (r=–0.833 to –0.894), a moderate positive correlation with visceral fat areas (r=0.607 to 0.669), and a weak positive correlation with the subcutaneous fat areas (r=0.305 to 0.441).

Conclusions

The automated web-based toolkit is feasible and enables quantitative CT assessment of myosteatosis, which can be a potential quantitative biomarker for evaluating structural and functional changes brought on by aging in the skeletal muscle.

Adaptive Compressive Tomography with No a priori Information

Quantum state tomography is both a crucial component in the field of quantum information and computation and a formidable task that requires an incogitable number of measurement configurations as the system dimension grows. We propose and experimentally carry out an intuitive adaptive compressive tomography scheme, inspired by the traditional compressed-sensing protocol in signal recovery, that tremendously reduces the number of configurations needed to uniquely reconstruct any given quantum state without any additional a priori assumption whatsoever (such as rank information, purity, etc.) about the state, apart from its dimension.

Accurate Extraction of Coronary Vascular Structures in 2D X-ray Angiogram Using Vascular Topology Information in 3D Computed Tomography Angiography

Since the 2D X-ray angiogram enables the detection of vascular stenosis in real-time, it is essential for percutaneous coronary intervention (PCI). However, the accurate vascular structure is very difficult to determine due to background clutter and loss of depth information of 2D projection. To cope with these difficulties, we propose a fast and accurate extraction method of a vascular structure in 2D X-ray angiogram (XA) based on the vascular topology information of 3D computed tomography angiography (CTA) of the same patient. First, an initial vascular structure is robustly extracted based on vessel enhancement filtering. Then, 2D XA and 3D CTA are spatially aligned by 2D–3D registration. Finally, the 2D vascular structure is accurately reconstructed based on 3D vascular topology information by measuring the similarity of 2D and 3D vascular segments. Experimental results showed the fast and accurate extraction of a vascular structure using 10 images each of the left coronary artery (LCA) and right coronary artery (RCA). Our method can be used as a computer-aided technology for PCI. Our method can be applied to the study of other various types of vessels.

Anti-pruritic effect of topical capsaicin against histamine-induced pruritus on canine skin

Several human studies have reported that capsaicin has anti-pruritic effects. Moreover, sever- al concentrations of topical capsaicin have been used to alleviate itch. The aim of this study was to investigate the anti-pruritic effect of capsaicin against histamine-induced pruritus compared with that of topical steroid or vehicle in 15 healthy beagles. Fifteen dogs were divided into three groups (n = 5 each), and treated topically with one of the following on the left side of the neck: capsaicin, positive control (steroid), or negative control (vehicle). Each treatment was performed twice daily for 8 days. All dogs were injected with histamine intradermally before treatment and on the 2nd, 4th, 6th, and 8th days of the treatment to evoke itch. Pruritus, wheal, and erythema intensity were assessed at each evaluation; cutaneous temperature was also recorded. On the final day, skin biopsy was conducted for histopathological evaluation for all dogs. The severity of pruritus was lesser in the capsaicin-treated group compared with the negative control group on day 8 (p⟨0.05). In the capsaicin and steroid groups, wheal size, erythema index, and cutaneous temperature also decreased compared with pretreatment. Histopathological evaluation showed that the capsaicin-treated group had a higher number of inflammatory cells in the dermis com- pared to the vehicle control group; however, the steroid-treated group showed less severe inflam- matory reactions than the vehicle control group. These results suggest that capsaicin cannot reduce inflammation but may play a helpful role in reducing pruritus in dogs.

Broadband Surface Plasmon Lasing in One-dimensional Metallic Gratings on Semiconductor

We report surface plasmon (SP) lasing in metal/semiconductor nanostructures, where one-dimensional periodic silver slit gratings are placed on top of an InGaAsP layer. The SP nature of the lasing is confirmed from the emission wavelength governed by the grating period, polarization analysis, spatial coherence, and comparison with the linear transmission. The excellent performance of the device as an SP source is demonstrated by its tunable emission in the 400-nm-wide telecom wavelength band at room temperature. We show that the stimulated emission enhanced by the Purcell effect enables successful SP lasing at high energies above the gap energy of the gain. We also discuss the dependence of the lasing efficiency on temperature, grating dimension, and type of metal.

Experimental Infection of Goats with a Newly Isolated Strain of Akabane Virus that Causes Encephalomyelitis

In 2010, there was a large-scale outbreak of bovine encephalomyelitis in Korea, and 15 new strains of Akabane virus (AKAV) were isolated. To identify the pathogenicity of one of these strains, we infected adult goats with AKAV-7 via different routes. Twenty-five female goats were used in this study and were divided into five groups: intracerebral (IC) and intrasubarachnoid (IS) viral inoculation (n = 8 each), intravenous (IV) inoculation (n = 4), and vaccinated before IV inoculation (n = 4), in addition to a negative control animal. All animals inoculated with AKAV-7 had AKAV-neutralizing antibodies at 6-8 days post infection (dpi). During the experimental period, infected animals showed no clinical signs. In the IC group, 5/8 goats had non-suppurative encephalomyelitis affecting the cerebrum. Virus S RNA segments were detected in nearly all areas of the brain. In the IS group, 3/8 goats had encephalomyelitis affecting the cerebrum, cerebellum and spinal cord. At 7 and 21 dpi, virus S RNA segments were found mostly in the spinal cord, especially around the area of injection (L5-L6). Antibody titres in the serum of the vaccinated group had an early onset and slightly increased titre compared with the IV group. Histopathologically, there were no obvious lesions in the central nervous tissues in the vaccinated group, while one of four goats in the IV group showed encephalomyelitis in the parietal lobe of the cerebrum. The newly isolated AKAV-7 can cause encephalomyelitis in goats after experimental injection. The attenuated AKAV vaccine currently used in Korea may provide partial protective immunity against AKAV-7 infection, but the real effect of the vaccine requires further investigation in goats.