GS-DeepNet: mastering tokamak plasma equilibria with deep neural networks and the Grad-Shafranov equation

The force-balanced state of magnetically confined plasmas heated up to 100 million degrees Celsius must be sustained long enough to achieve a burning-plasma state, such as in the case of ITER, a fusion reactor that promises a net energy gain. This force balance between the Lorentz force and the pressure gradient force, known as a plasma equilibrium, can be theoretically portrayed together with Maxwell's equations as plasmas are collections of charged particles. Nevertheless, identifying the plasma equilibrium in real time is challenging owing to its free-boundary and ill-posed conditions, which conventionally involves iterative numerical approach with a certain degree of subjective human decisions such as including or excluding certain magnetic measurements to achieve numerical convergence on the solution as well as to avoid unphysical solutions. Here, we introduce GS-DeepNet, which learns plasma equilibria through solely unsupervised learning, without using traditional numerical algorithms. GS-DeepNet includes two neural networks and teaches itself. One neural network generates a possible candidate of an equilibrium following Maxwell's equations and is taught by the other network satisfying the force balance under the equilibrium. Measurements constrain both networks. Our GS-DeepNet achieves reliable equilibria with uncertainties in contrast with existing methods, leading to possible better control of fusion-grade plasmas.

Cost-effectiveness Analysis of Subcutaneous Infliximab for Inflammatory Bowel Diseases in Sequential Biologic Treatment

BACKGROUND

Inflammatory bowel disease (IBD) guidelines recommend tumor necrosis factor-α inhibitors (TNFis) for patients who have not responded to conventional therapy, and vedolizumab in case of inadequate response to conventional therapy and/or TNFis. Recent studies have shown that vedolizumab may also be effective in the earlier treatment lines. Therefore, we conducted cost-effectiveness analyses to determine the optimal treatment sequence in patients with IBD.

METHODS

A Markov model with a 10-year time horizon compared the cost-effectiveness of different biologic treatment sequences in patients with moderate to severe ulcerative colitis (UC) and Crohn's disease (CD) from the UK and French perspectives. Subcutaneous formulations of infliximab, vedolizumab, and adalimumab were evaluated. Comparative effectiveness was based on a network meta-analysis of clinical trials and real-world evidence. Costs included pharmacotherapy, surgery, adverse events, and disease management.

RESULTS

The results indicated that treatment sequences starting with infliximab were less costly and more effective than those starting with vedolizumab for patients with UC in the United Kingdom and France, and patients with just CD in France. For patients with CD in the United Kingdom, treatment sequences starting with infliximab resulted in better health outcomes with incremental cost-effectiveness ratios (ICERs) near the threshold.

CONCLUSIONS

Based on the ICERs, treatment sequences starting with infliximab are the dominant option for patients with UC in the United Kingdom, and patients with UC and CD in France. In UK patients with CD, ICERs were near the assumed "willingness to pay" threshold. These results reinforce the UK's National Institute for Health and Care Excellence recommendations for using infliximab prior to using vedolizumab in biologics-naïve patients.

Fast-ion Dα spectroscopy diagnostic at KSTAR

A fast-ion Dα (FIDA) diagnostics system was installed for core and edge measurements on KSTAR. This system has two tangential FIDA arrays that cover both blue- and redshifted Dα lines (cold: 656.09 nm) in active views along the neutral beam 1 A centerline. The spectral band is 647-662.5 nm, and it covers the Doppler shift of the emission from the maximum energy of the neutral beam (100 keV). A curved filter strip with a motorized stage adequately prevents saturation of the electron multiplying charge-coupled device signal by the cold Dα line from the plasma edge. From comparisons of the measured spectra and FIDASIM modeling code, the FIDA spectra are well matched quantitatively. Moreover, the first measurements show that the FIDA radiance agrees with the neutron rate in the time trace during external heating and perturbation. In addition, responses are observed in the core FIDA radiance during the edge-localized mode cycle.

Poor nutritional intake is a dominant factor for weight loss in chronic obstructive pulmonary disease

<sec id="st1"> <title>SETTING</title> Increase in energy expenditure and/or decrease in nutritional intake leads to low body mass index (BMI). The balance between energy expenditure and nutritional intake has rarely been evaluated in a large population of patients with chronic obstructive pulmonary disease (COPD). </sec> <sec id="st2"> <title>OBJECTIVE</title> To evaluate BMI, nutritional intake and physical activity and the association of these factors with the severity of airflow obstruction in COPD patients. </sec> <sec id="st3"> <title>DESIGN</title> We analysed the Korean National Health and Nutrition Examination Survey (KNHANES) data set from 2012 to 2015. </sec> <sec id="st4"> <title>RESULTS</title> Among the 9682 individuals (1601 with COPD and 8081 without COPD) recruited, BMI was lower in COPD patients than in non-COPD participants (males, 23.86 ± 2.76 vs. 24.28 ± 2.80, P < 0.001; females, 23.63 ± 2.94 vs. 23.98 ± 3.10, P < 0.05). As the stage of COPD advanced, BMI, intake of nutrients (food, water and carbohydrates) and total energy levels declined in COPD patients. Total time spent walking in the preceding week decreased with advancing COPD stage in male patients with COPD. COPD severity was an important risk factor for the limitation of physical activity due to respiratory problems (OR 3.92, 95%CI 2.77∼5.34, P < 0.001). </sec> <sec id="st5"> <title>CONCLUSION</title> Patients with COPD had a low nutritional intake with little physical activity, which worsened with advancing COPD stage. In late-stage COPD, impaired nutritional intake outweighed the decrease in physical activity, resulting in weight loss. </sec>.

Propagation Dynamics Associated with Resonant Magnetic Perturbation Fields in High-Confinement Mode Plasmas inside the KSTAR Tokamak

The propagation dynamics of resonant magnetic perturbation fields in KSTAR H-mode plasmas with injection of small edge perturbations produced by a supersonic molecular beam injection is reported for the first time. The results show that the perturbation field first excites a plasma response on the q=3 magnetic surface and then propagates inward to the q=2 surface with a radially averaged propagation velocity of resonant magnetic perturbations field equal to 32.5  m/ s. As a result, the perturbation field brakes the toroidal rotation on the q=3 surface first causing a momentum transport perturbation that propagates both inward and outward. A higher density fluctuation level is observed. The propagation velocity of the resonant magnetic perturbations field is larger than the radial propagation velocity of the perturbation in the toroidal rotation.

Experimental infection of clade 1.1.2 (H5N1), clade 2.3.2.1c (H5N1) and clade 2.3.4.4 (H5N6) highly pathogenic avian influenza viruses in dogs

Since the emergence of highly pathogenic avian influenza (HPAI) H5N1 in Asia, the haemagglutinin (HA) gene of this virus lineage has continued to evolve in avian populations, and H5N1 lineage viruses now circulate concurrently worldwide. Dogs may act as an intermediate host, increasing the potential for zoonotic transmission of influenza viruses. Virus transmission and pathologic changes in HPAI clade 1.1.2 (H5N1)-, 2.3.2.1c (H5N1)- and 2.3.4.4 (H5N6)-infected dogs were investigated. Mild respiratory signs and antibody response were shown in dogs intranasally infected with the viruses. Lung histopathology showed lesions that were associated with moderate interstitial pneumonia in the infected dogs. In this study, HPAI H5N6 virus replication in dogs was demonstrated for the first time. Dogs have been suspected as a "mixing vessel" for reassortments between avian and human influenza viruses to occur. The replication of these three subtypes of the H5 lineage of HPAI viruses in dogs suggests that dogs could serve as intermediate hosts for avian-human influenza virus reassortment if they are also co-infected with human influenza viruses.

An introduction to biosimilar cancer therapeutics: definitions, rationale for development and regulatory requirements

Monoclonal antibodies and other biologic drugs play important roles in the treatment of various hematological malignancies and solid tumors. However, such drugs are intrinsically more expensive to develop than small molecules and their clinical benefits are often accompanied by challenges relating to affordability and access. Patent expiry for ‘originator’ biologics is providing opportunities for a new generation of biosimilar drugs, potentially capable of relieving pressure on healthcare budgets. This article discusses key characteristics of biosimilars, distinguishes them from generics and noncomparable biologics and outlines the robust regulatory requirements that must be followed to establish biosimilarity with a reference product. The path to approval is discussed with reference to the rituximab biosimilar CT-P10, the first licensed monoclonal antibody biosimilar cancer therapeutic.

Scientific rationale for extrapolation of biosimilar data across cancer indications: case study of CT-P10

For a biosimilar to gain regulatory approval, a comprehensive comparability exercise must demonstrate that it is highly similar to its originator biologic, or reference product. Once biosimilarity has been shown, it is possible to approve the biosimilar for additional indications held by the reference product, without clinical trials in these indications. Extrapolation of clinical data is permitted by regulatory agencies as long as it is scientifically justified. CT-P10, a biosimilar of rituximab, was recently approved in Europe for all indications held by its reference product, incorporating both autoimmune diseases and hematological cancers. Here, we review the scientific rationale for extrapolation in biosimilar development using the example of CT-P10 as a case study.

Efficacy of single-dose gonadotropin-releasing hormone agonist administration prior to magnetic resonance-guided focused ultrasound surgery for symptomatic uterine fibroids

PURPOSE

To investigate the effects of a single-dose GnRHa on the thermal ablation of MRgFUS in women with symptomatic fibroids.

MATERIALS AND METHOD

In this pilot study, a single-dose GnRHa was administered in 17 patients with a total of 20 fibroids. Volume and scaled signal intensity (SSI) as an objective marker of fluid contents were prospectively followed up with serial MR scans. The control group of 17 patients with 19 fibroids were retrospectively enrolled and compared with GnRHa group in terms of non-perfused volume (NPV) and thermal dosimetry to assess the efficiency of thermal ablation.

RESULTS

About 29 days after GnRHa administration, SSI and volume of fibroids were reduced by 55.1 and 10.6%, respectively (p < 0.05) but no adverse events were reported. NPV per unit energy (0.046 cm³/J ± 0.026 vs. 0.031 cm³/J ± 0.018, p = 0.041) was larger and SSI (8.4 ± 8.0 vs. 13.9 ± 12.0, p = 0.053) was lower in GnRHa group. Linear regression analysis showed that these two parameters were in a reverse correlation (p = 0.011).

CONCLUSION

GnRHa is supposed to reduce the fluid contents of fibroids including blood vessels and enhance the tissue responsiveness to thermal energy. A single dose prior to MRgFUS has the potential to improve treatment efficiency, while avoiding the side effects of multiple doses of GnRHa.

Anti-Metastatic Effect of Dehydrocorydaline on H1299 Non-Small Cell Lung Carcinoma Cells via Inhibition of Matrix Metalloproteinases and B Cell Lymphoma 2

Though Dehydrocorydaline, an alkaloid isolated from Corydalis turtschaninovii tuber, was known to have anti-coronary artery disease, anti-inflammatory, apoptotic, anti-allergic, anti-acetylcholinesterase, and antitumor effects, the underlying anti-metastatic mechanism of Dehydrocorydalin was never elucidated in lung cancer cells so far. Thus, in the present study, the anti-metastatic effect of Dehydrocorydaline was examined in non-small cell lung carcinoma (NSCLC) cells, mainly targeting matrix metalloproteinases (MMPs) and B cell lymphoma-2 (Bcl-2) signaling. Here, Dehydrocorydaline exerted weak cytotoxicity and attenuated the protein expression of Bcl-2 and activated Bax in a concentration-dependent manner in NSCLC cells, such as A549, H460, H1299, and H596 cells. Also, Dehydrocorydaline suppressed the migration of H1299 cells by wound healing assay and transwell migration assay. Consistently, Dehydrocorydaline attenuated mRNA and protein levels of MMP7 and MMP9 as metastasis biomarkers in H1299 cells by quantitative reverse transcription polymerase chain reaction. Of note, Bcl-2 overexpression reduced the cytotoxic and anti-metastatic effects of Dehydrocorydaline on pCDNA-Bcl-2 transfected H1299 cells. Overall, our findings provide scientific evidence that Dehydrocorydaline exerts anti-metastatic potential via suppression of MMPs and Bcl-2 signaling in NSCLC cells. Copyright © 2017 John Wiley & Sons, Ltd.

Blockage of epithelial to mesenchymal transition and upregulation of let 7b are critically involved in ursolic acid induced apoptosis in malignant mesothelioma cell

Malignant pleural mesothelioma (MPN), which is caused by asbestos exposure, is one of aggressive lung tumors. In the present study, we elucidated the anti-tumor mechanism of ursolic acid in malignant mesotheliomas. Ursolic acid significantly exerted cytotoxicity in a time and dose dependent manner in H28, H2452 and MSTO-211H mesothelioma cells and inhibited cell proliferation by colony formation assay in a dose-dependent fashion. Also, ursolic acid treatment accumulated the sub-G1 population, attenuated the expression of procapase 9, cyclin D1, pAKT, p-glycogen synthase kinase 3-alpha/beta (pGSK3α/β), β-catenin and nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB) and also cleaved caspase 3 and poly (ADP-ribose) polymerase (PARP) in mesothelioma cells. Furthermore, ursolic acid treatment blocked epithelial and mesenchymal transition (EMT) molecules by activating E-cadherin as an epithelial marker and attenuating Vimentin, and Twist as mesenchymal molecules. Interestingly, miRNA array revealed that 23 miRNAs (>2 folds) including let-7b and miRNA3613-5p, miRNA134 and miRNA196b were significantly upregulated while 33 miRNAs were downregulated in ursolic acid treated H2452 cells. Furthermore, overexpression of let 7b using let-7b mimics enhanced the antitumor effect of ursolic acid to attenuate the expression of procaspases 3, pro-PARP, pAKT, β-catenin and Twist and increase sub-G1 accumulation in H2452 mesothelioma cells. Overall, our findings suggest that ursolic acid induces apoptosis via inhibition of EMT and activation of let7b in mesothelioma cells as a potent chemotherapeutic agent for treatment of malignant mesotheliomas.

Comparing the meanings of living with advanced breast cancer between women resilient to distress and women with persistent distress: a qualitative study

BACKGROUND

Most women with advanced breast cancer (ABC) show little distress, but about one in ten show persistent distress over time. It remains unclear if meanings ascribed by patients to ABC differentiate these distress trajectories.

STUDY AIMS

This qualitative study (a) compared illness meanings of ABC between women with persistent psychological distress and those with low/transient distress, and (b) examined how illness meanings might influence coping strategies.

METHODS

The sample was drawn from a prior quantitative study exploring psychological distress trajectories following ABC diagnosis. Overall, 42 Cantonese- or Mandarin-speaking Chinese women diagnosed with locally advanced or metastatic ABC were recruited based on their distress trajectory status (low-stable, transient, or persistent distress). Interviews were recorded, transcribed, and analyzed following grounded theory approach using simultaneous analysis.

RESULTS

Women with persistent distress viewed their diagnosis as another blow in life, the illness was global, permeating every aspect of their life. Maladaptive rumination and thought suppression were common responses to illness demands. These women had poor social support. A sense of demoralization stood out in their narratives. In contrast, women with transient/low-stable distress encapsulated the illness, with minimum impacts of their life. They did not evidence dysfunctional repetitive thoughts. Living in a supportive environment, they were able to accept and/or live in the present-moment.

CONCLUSIONS

Rumination, thought suppression, social constraints, and pre-existing exposure to life stress may be potential risks for chronic distress in response to advanced breast cancer. Persistent and transient distress responses to cancer may have different underpinnings. Copyright © 2016 John Wiley & Sons, Ltd.

CCR4-NOT2 Promotes the Differentiation and Lipogenesis of 3T3-L1 Adipocytes via Upregulation of PPARx03B3;, CEBPα and Inhibition of P-GSK3α/β and β-Catenin

BACKGROUND/AIMS

Though CCR4-NOT2 (CNOT2), one of CCR4-NOT complex subunits, was known to be involved in metastasis and apoptosis through transcription and mRNA degradation, its other biological function is poorly understood so far. The aim of this study is to elucidate the molecular role of CNOT2 in the differentiation process of 3T3-L1 preadipocytes.

METHODS AND RESULTS

CNOT2 was overexpressed during the differentiation process of 3T3-L1 preadipocytes. Consistently, mRNA levels of CNOT2, adiponectin, adiponectin 2, PPARx03B3; and CEBPα were enhanced in 3T3-L1 adipocytes. Conversely, CNOT2 depletion by siRNA transfection also reversed the activation of PPARx03B3; and CEBPα and inhibition of GSK3α/β and β-catenin at the protein level in 3T3-L1 preadipocytes. Immunofluorescence assay revealed that CNOT2 was colocalized with PPARx03B3;, but not with CEBPα in 3T3-L1 adipocyte. Consistently, IP western blots revealed that CNOT2 interacted with PPARx03B3; in 3T3-L1 adipocyte.

CONCLUSION

Our findings demonstrate that CNOT2 promotes the differentiation of 3T3-L1 preadipocytes via upregulation of PPARx03B3;, and CEBPα and inhibition of GSK3α/β and β-catenin signaling as a potent molecular target for obesity.

Abstract 1014: Dihydrotanshione I induces caspase-independent cell death and autophagy in lung cancer cells

In the present study the antitumor mechanism of dihydrotanshinone I (DHT) from Salvia miltiorrhiza Bunge was elucidated in lung cancer cells. DHT significantly exerted cytotoxicity and increased the apoptosis by Annexin V assay in NSCLC (A549 and H460 cells) and lung mesothelioma cells (H28, H2452, MSTO). Furthermore, DHT reduced clonogenic ability in A549 cells. Interestingly, DHT increased PARP cleavage, but no activation of caspase-9 and caspase-3, although caspase-8 and, 3 were partially activated. FACS analysis revealed that the pan-caspase inhibitor z-VAD-fmk increased apoptosis induced by DHT. Furthermore, MTT assay showed that z-VAD-fmk treatment did not block cell cytotoxicity induced by DHT. In contrast, DHT induced the features of autophagy, including formation of autophagosomes by immunofluorescence and an increase of LC3II level after DHT exposure. Treatment of 3MA, an inhibitor of autophagy, blocked the expression level of LC3II induced by DHT and induced cytoprotective autophagy in A549 cells. Taken together, our data suggest that DHT induces caspase-independent cell death and autophagy in lung cancer cells as a potent agent for lung cancer treatment.

Citation Format: Sung-Hoon Kim, Gunho Won, Myoung Seok Jeong, Sang Wook Yoon, Jihyun Lee, Bonglee Kim, Eun Jung Sohn. Dihydrotanshione I induces caspase-independent cell death and autophagy in lung cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1014. doi:10.1158/1538-7445.AM2015-1014

Abstract 1015: Misaponin B induces G2-M arrest and autophagy via upregulation of miR1290 in non-small cell lung cancer (NSCLC) A549 cells

Though Mi-saponin B is found to be the potent component among a mixture of saponins, its function still remains unlcear. Thus, in the present study, we investigated the anti-tumor mechanism of Mi-saponin B in non-small cell lung cancer (NSCLC) A549 cells. Mi-saponin B treatment caused cell growth inhibition via G2/M arrest in A549 cells. Moreover, Western blotting and qRT-PCR assays showed that Mi-saponin B induced conversion of LC3I to LC3II, a maker of autophagy. Immunofluorescence assay revealed that Mi-saponin B treatment formed the puncta of GFP-fused LC3II. Conversely, 3MA, an inhibitor of autophagy, attenuated the LC3II expression induced by Mi-saponin B in A549 cells. Also, transmission electron microscopy (TEM) showed that Mi-saponin B induces the autophagic vacuoles. Interestingly, miR1290 was upregulated in a dose dependent manner in Mi-saponin B treated A549 cells by qRT-PCR. Also, combined treatment of miR1290 and Mi-saponin B increased the expression of LC3II at protein and mRNA levels and also enhanced the formation of puncta of LC3II in A549 cells. Overall, our findings for the first time demonstrate that Mi-saponin B induces G2/M arrest and autophagy via upregulation of miR1290 in A549 cells as a potent anti-cancer agent.

Citation Format: Gunho Won, Eun Jung Sohn, Myoung Seok Jeong, Sang Wook Yoon, Jihyun Lee, Bonglee Kim, Sung Hoon Kim. Misaponin B induces G2-M arrest and autophagy via upregulation of miR1290 in non-small cell lung cancer (NSCLC) A549 cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1015. doi:10.1158/1538-7445.AM2015-1015

Usefulness of the ratio of orbital fat to total orbit area in mild-to-moderate thyroid-associated ophthalmopathy

OBJECTIVE

To identify a useful predictor of thyroid-associated ophthalmopathy (TAO) from orbital CT images; to evaluate the orbital fat and extraocular muscle area ratio as a CT-derived measure; and to investigate the correlations between this ratio and the clinical manifestations in mild-to-moderate TAO.

METHODS

Between January 2012 and March 2013, 44 patients with TAO and 23 controls were studied prospectively. All of the patients underwent ophthalmic examinations, including clinical activity score, exophthalmometry, clinical photographs, alternate prism and cover test, duction and version test, Hess screen test, binocular single vision test, thyroid function tests and orbital CT. The cross-sectional areas of the four rectus muscles, superior oblique muscle, optic nerve and total orbit area were calculated in the coronal view 6 mm posterior from the posterior pole of globe.

RESULTS

The cross-sectional area measured on orbital CT showed increased orbital fat in patients with TAO and an increased orbital fat to total orbit area ratio (fat/orbit) in TAO with retraction and proptosis. There were significant correlations between fat/orbit and margin reflex distance 1 (p = 0.022), margin reflex distance 2 (p = 0.013) and the exophthalmometric value (p = 0.007).

CONCLUSION

The orbital fat to total orbit area ratio (fat/orbit) is a useful diagnostic index in mild-to-moderate TAO.

ADVANCES IN KNOWLEDGE

The orbital CT offers a useful diagnostic index in TAO.

Rotation characteristics during the resonant magnetic perturbation induced edge localized mode suppression on the KSTAR

Measuring rotation profiles with a reliable spatial resolution is one of the critical diagnostics in understanding the plasma behavior especially for the edge transport. In the KSTAR experiments, it has been consistently observed from the charge exchange spectroscopy measurements that the magnetic perturbations not only suppresses edge localized modes (ELMs) but also reduces toroidal rotations. In this paper, toroidal velocities of the carbon impurity and their profile evolutions during ELMy and ELM-suppressed phases are presented. The rotation profiles are shown to collapse immediately after an ELM burst and continue to build up until the next burst that accompanies another collapse. Toroidal rotations following the resonant magnetic perturbations applications are observed to be reduced along with the ELMs suppressed.

Edge profile measurements using Thomson scattering on the KSTAR tokamak

In the KSTAR Tokamak, a "Tangential Thomson Scattering" (TTS) diagnostic system has been designed and installed to measure electron density and temperature profiles. In the edge system, TTS has 12 optical fiber bundles to measure the edge profiles with 10-15 mm spatial resolution. These 12 optical fibers and their spatial resolution are not enough to measure the pedestal width with a high accuracy but allow observations of L-H transition or H-L transitions at the edge. For these measurements, the prototype ITER edge Thomson Nd:YAG laser system manufactured by JAEA in Japan is installed. In this paper, the KSTAR TTS system is briefly described and some TTS edge profiles are presented and compared against the KSTAR Charge Exchange Spectroscopy and other diagnostics. The future upgrade plan of the system is also discussed in this paper.

Rotational resonance of nonaxisymmetric magnetic braking in the KSTAR tokamak

One of the important rotational resonances in nonaxisymmetric neoclassical transport has been experimentally validated in the KSTAR tokamak by applying highly nonresonant n=1 magnetic perturbations to rapidly rotating plasmas. These so-called bounce-harmonic resonances are expected to occur in the presence of magnetic braking perturbations when the toroidal rotation is fast enough to resonate with periodic parallel motions of trapped particles. The predicted and observed resonant peak along with the toroidal rotation implies that the toroidal rotation in tokamaks can be controlled naturally in favorable conditions to stability, using nonaxisymmetric magnetic perturbations.

Appearance and dynamics of helical flux tubes under electron cyclotron resonance heating in the core of KSTAR plasmas

Dual (or sometimes multiple) flux tubes (DFTs) have been observed in the core of sawtoothing KSTAR tokamak plasmas with electron cyclotron resonance heating. The time evolution of the flux tubes visualized by a 2D electron cyclotron emission imaging diagnostic typically consists of four distinctive phases: (1) growth of one flux tube out of multiple small flux tubes during the initial buildup period following a sawtooth crash, resulting in a single dominant flux tube along the m/n=1/1 helical magnetic field lines, (2) sudden rapid growth of another flux tube via a fast heat transfer from the first one, resulting in approximately identical DFTs, (3) coalescence of the two flux tubes into a single m/n=1/1 flux tube resembling the internal kink mode in the normal sawteeth, which is explained by a model of two current-carrying wires confined on a flux surface, and (4) fast localized crash of the merged flux tube similar to the standard sawtooth crash. The dynamics of the DFTs implies that the internal kink mode is not a unique prerequisite to the sawtooth crash, providing a new insight on the control of the sawtooth.

Initial measurements of fast ion loss in KSTAR

A fast ion loss detector (FILD) has been installed and tested in Korea Superconducting Tokamak Advanced Research (KSTAR). KSTAR FILD measures the energy and the pitch-angle of the escaping ions with the striking positions on the scintillator plane. Measurements of the fast ion loss have been performed for the neutral beam heated plasmas. Initial experimental results indicate the prompt losses from neutral beam are dominant and the effects of the resonant magnetic perturbation on the fast ion loss are investigated. In addition, further design change of the detector-head in order to avoid excessive heat load and to detect the fusion products or the fast ions having order of MeV of energy is also discussed.

Suppression of edge localized modes in high-confinement KSTAR plasmas by nonaxisymmetric magnetic perturbations

Edge localized modes (ELMs) in high-confinement mode plasmas were completely suppressed in KSTAR by applying n=1 nonaxisymmetric magnetic perturbations. Initially, the ELMs were intensified with a reduction of frequency, but completely suppressed later. The electron density had an initial 10% decrease followed by a gradual increase as ELMs were suppressed. Interesting phenomena such as a saturated evolution of edge T(e) and broadband changes of magnetic fluctuations were observed, suggesting the change of edge transport by the applied magnetic perturbations.

Phosphorylation of ORC2 protein dissociates origin recognition complex from chromatin and replication origins

During the late M to the G(1) phase of the cell cycle, the origin recognition complex (ORC) binds to the replication origin, leading to the assembly of the prereplicative complex for subsequent initiation of eukaryotic chromosome replication. We found that the cell cycle-dependent phosphorylation of human ORC2, one of the six subunits of ORC, dissociates ORC2, -3, -4, and -5 (ORC2-5) subunits from chromatin and replication origins. Phosphorylation at Thr-116 and Thr-226 of ORC2 occurs by cyclin-dependent kinase during the S phase and is maintained until the M phase. Phosphorylation of ORC2 at Thr-116 and Thr-226 dissociated the ORC2-5 from chromatin. Consistent with this, the phosphomimetic ORC2 protein exhibited defective binding to replication origins as well as to chromatin, whereas the phosphodefective protein persisted in binding throughout the cell cycle. These results suggest that the phosphorylation of ORC2 dissociates ORC from chromatin and replication origins and inhibits binding of ORC to newly replicated DNA.

Modelling a turbidity current in Soyang reservoir (Korea) and its control using a selective withdrawal facility

Persistent turbidity in reservoirs and their downstream after flood events is one of most important environmental issues in Korea. Recently, modification of withdrawal facility and installation of a new selective withdrawal structure (SWS) have been implemented for the mitigation of downstream impact and sediment loading into water treatment facilities. This study was to explore the characteristics of flood density flow induced into Soyang Reservoir and the transport processes of suspended sediments (SS) through application of coupled two-dimensional hydrodynamic and particle dynamic models (TM-1, TM-2 and TM-3). The TM-3 including a turbidity attenuation rate as a lumped parameter showed best performance in reproducing the magnitude and distribution of SS in the reservoir. The validated model was applied to evaluate the effectiveness of SWS, which was designed for the reservoir, with 6 different historical flood events. The magnitude of vertical mixing of the turbidity plume and its persistence within the reservoir were closely correlated to the ratio of the volume of turbidity flow to the total reservoir storage (the theta value). The operation of SWS showed a positive effect as long as theta is between 0.3 and 0.6 but negative when theta = 0.83 for the study reservoir, thus it should be optimized based on the theta value for a better management of the reservoir.

Wearable EDA sensor gloves using conducting fabric and embedded system

We developed wearable EDA sensor gloves using conducting fabric and embedded system. EDA(Electro-dermal Activity) signal is an electric response on the skin of the human body. There are SCL(Skin Conductance Level) and SCR(Skin Conductance Response) in EDA. Mostly, SCL consists of DC elements. On the other hand, SCR consists of AC elements. We use the relationship between the drowsiness condition and EDA signal We made EDA sensors using conducting fabric instead of Agcl electrode for a more suitable wearable device. And we used an embedded system for EDA signal acquisition and processing instead of a personal computer, which is connected to the EDA sensor gloves through conducting fabric lines. Also, the embedded system is linked to a Notebook PC that shows the results of EDA signal processing analysis and gives proper feedback to the user. This system, for example, can be used in detecting and preventing drowsiness driving accidents for automobile drivers.

alpha-MSH inhibits TNF-alpha-induced matrix metalloproteinase-13 expression by modulating p38 kinase and nuclear factor kappaB signaling in human chondrosarcoma HTB-94 cells

OBJECTIVE

Proinflammatory cytokine-induced expression of matrix metalloproteinases (MMPs) is a major cause of arthritic cartilage destruction. The neuropeptide, alpha-melanocyte-stimulating hormone (alpha-MSH), has been detected in the synovial fluid of arthritis patients, where it is thought to play an anti-inflammatory role. Here, we examined whether alpha-MSH acts via downregulation of MMP expression, and sought to elucidate the intracellular signal pathways underlying this effect.

DESIGN

Human chondrosarcoma cell line, HTB-94 (SW1353) was pretreated with or without alpha-MSH and then treated with tumor necrosis factor-alpha (TNF-alpha). The effect of alpha-MSH on TNF-alpha-induced MMP-13 expression and mitogen-activated protein kinases' (MAPKs) activation were determined by reverse transcriptase-polymerase chain reaction and Western blot analysis. Additionally, the intracellular signaling of alpha-MSH was investigated using the inhibitors of MAPK and nuclear factor kappaB (NF-kappaB) and plasmids encoding dominant negative (dn) forms of inhibitor kappaB kinase-alpha (IKKalpha) and inhibitor kappaB kinase-beta (IKKbeta).

RESULTS

We found that alpha-MSH pretreatment inhibited TNF-alpha-induced MMP-13 expression and p38 kinase phosphorylation in HTB-94 human chondrosarcoma cells. TNF-alpha-induced MMP-13 expression was not suppressed by extracellular signal-regulated kinase (ERK) inhibitors (PD98059 and U0126) or a c-jun terminal kinase (JNK) inhibitor (SP600125), but was inhibited by inhibitors of p38 kinase (SB203580) and NF-kappaB (SN-50 peptide) and dnIKKalpha and dnIKKbeta.

CONCLUSIONS

Our results suggest that alpha-MSH regulates TNF-alpha-induced MMP-13 expression by decreasing p38 kinase phosphorylation and subsequent NF-kappaB activation in human chondrocytes and may be an effective inhibitor of MMP-13-mediated collagen degradation, providing new potential opportunities for the development of anti-arthritis therapeutics.

Dependence of particle volume fraction on sound velocity and attenuation of EPDM composites

The sound velocity and the attenuation coefficient of EPDM (Ethylene-propylene Diene Monomer) composites incorporated with Silicon Carbide particles (SiCp's) of various volume fractions (0-40%) were experimentally and theoretically investigated. For the experiment a through-transmission technique was used. For the theoretical prediction, some mechanical property models such as Reuss model and Coherent Potential Approximation (CPA) model etc. were employed. The experimental results showed that the sound velocity decreased with the increase of the SiCp volume fraction up to 30% and then increased with the 40 vol% specimen. The attenuation coefficient was increased with the increasing SiCp volume fractions. The modified Reuss model with a longitudinal elastic modulus predicted most well the experimental sound velocity and elastic modulus results.

Burkitt's lymphoma representing periportal infiltrating mass on CT

Imaging findings of secondary hepatic lymphoma have been reported as variable, ranging from single or multiple small nodules to diffuse infiltrative tumor patterns. We hear present a rare case report concerning aggressive B cells, secondary Burkitt's lymphoma in non-AIDS demonstrating a surprising periportal lymphoma infiltration, without upper abdominal lymphadenopathy or splenomegaly on the sonography and CT scans. Clinically, the case was characterized by atypical and highly aggressive course, with the patient presenting an abruptly developed obstructive jaundice with rapidly deteriorating hepatic function that could be indicative of cholestatic hepatitis, which differs in its clinical manifestations from hepatic lymphoma without functional deterioration in respect of its non-tissue destructive growth pattern. We suggest that hepatic lymphoma can sometimes be consistent with periportal infiltrating homogeneous mass, with no lymphadenopathy or splenomegaly on the imaging examination, with a predictable aggressive clinical course of the disease and poor prognosis.

CT findings of surgically verified acute invasive small bowel anisakiasis resulting in small bowel obstruction

Acute invasive small bowel anisakiasis is an extremely rare cause of small bowel obstruction. The authors report a case of surgically verified small bowel anisakiasis resulting in small bowel obstruction. A 54-year-old man presented with suddenly developed diffuse abdominal pain after ingestion of raw fish. The peripheral blood examination showed leukocytosis without eosinophilia. CT showed a long segment of thickened small bowel accompanied by a focal narrowed portion and combined with ascites. When these findings are noted in patients with a history of recent ingestion of raw or undercooked fish, the diagnosis of small bowel anisakiasis should be considered in order to avoid application of unnecessary surgical treatment, in spite of the severity of the abdominal pain and bowel obstruction.

Bile duct injuries leading to portal vein obliteration after transcatheter arterial chemoembolization in the liver: CT findings and initial observations

PURPOSE

To document the computed tomographic (CT) findings of transcatheter arterial chemoembolization (TACE)-induced, localized bile duct injuries leading to portal vein branch obliteration in the liver and to elucidate the clinical implications with retrospective review of the authors' experiences.

MATERIALS AND METHODS

Follow-up CT scans obtained in 11 patients with TACE-induced intrahepatic bile duct dilatation were reviewed retrospectively to evaluate serial changes in the adjacent portal vein branches and hepatic parenchyma. Clinical data, including time between TACE and CT and serum alkaline phosphatase levels, also were analyzed.

RESULTS

Of 11 patients with marked (n = 8) or mild (n = 3), lobar (n = 4) or segmental (n = 7) bile duct dilatation with or without bile collection in the tissue sheaths of the Glisson capsule or hepatic parenchyma, nine (82%) had bile duct changes at the first CT follow-up, within 1 month after TACE. Marked narrowing or obliteration of the adjacent intrahepatic portal vein branches in 10 (91%) patients resulted in progressive atrophy of the corresponding hepatic parenchyma in nine (82%) at variable times after TACE. The serum alkaline phosphatase level increased to more than 200 U/L in eight (89%) of nine patients 1 month after TACE.

CONCLUSION

TACE-induced intrahepatic bile duct injury resulting in obliteration of the adjacent portal vein branch seems to be one cause of hepatic parenchymal atrophic changes after TACE.

Recurrent pyogenic cholangitis: comparison between MR cholangiography and direct cholangiography

PURPOSE

To compare the accuracy of magnetic resonance (MR) cholangiography with that of direct cholangiography for the evaluation of recurrent pyogenic cholangitis.

MATERIALS AND METHODS

Twenty-four patients with recurrent pyogenic cholangitis underwent MR cholangiography before surgery, and 18 of these 24 also underwent direct cholangiography. Two reviewers evaluated MR cholangiograms and direct cholangiograms and focused on identifying intrahepatic ductal dilatation, stricture, and calculi, as well as coexistent parenchymal abnormalities, on the basis of the classification of the internal lobes and segments of the liver. These observations were compared with surgical findings.

RESULTS

According to examination results in the surgical specimens, 24 patients had 46 segmental abnormalities. MR cholangiography depicted all 46 (100%) segments with ductal dilatation, 22 (96%) of 23 segments with focal ductal stricture, and 43 (98%) of 44 segments with ductal calculi. Eighteen patients who underwent direct cholangiography had 32 segmental abnormalities according to examination results in the surgical specimens. Direct cholangiography depicted 15 (47%) of 32 segments with ductal dilatation, eight (44%) of 18 segments with focal ductal stricture, and 14 (45%) of 31 segments with ductal calculi.

CONCLUSION

MR cholangiography is superior to direct cholangiography for accurate topographic evaluation of recurrent pyogenic cholangitis because it is able to depict all of the biliary tree, despite obstruction or stenosis.

Multicenter surveillance study for nosocomial infections in major hospitals in Korea. Nosocomial Infection Surveillance Committee of the Korean Society for Nosocomial Infection Control

BACKGROUND

The goals of a surveillance for nosocomial infections (NIs) are to observe the magnitude and characteristics of NIs and to plan and evaluate policies and guidelines of infection control. This study was designed to determine the rate and distribution of NIs and their causative pathogens in Korean hospitals.

METHODS

Prospective surveillance was performed at 15 acute care hospitals with more than 500 beds during a 3-month period from June to August 1996. The case-finding methods were laboratory-based surveillance for patients in the general wards and a direct review of medical charts done regularly for all the patients in the intensive care units.

RESULTS

A total of 3162 NIs were found among 85,547 discharged patients, with an overall nosocomial infection rate of 3.70 per 100 patients discharged. Urinary tract infections constituted 30.3% of all NIs. Other infections were pneumonias, 17.2%, surgical site infections, 15.5%, and primary bloodstream infections, 14.5%. The infection rate was the highest in neurosurgery (14.21), followed by neurology (8. 62) and ontology services (6.70). The infection rate in intensive care units was higher than it was in the general wards (10.74 vs 2. 57, P =.001). The commonly isolated organisms were Staphylococcus aureus (17.2%), Pseudomonas aeruginosa (13.8%), and Escherichia coli (12.3%).

CONCLUSIONS

This first multicenter surveillance study provided extensive information on the current status and trends of NIs in major hospitals in Korea. The results may contribute to the evaluation of infection control programs and the development of effective strategies in these hospitals.

Hepatic cavernous hemangioma in cirrhotic liver: imaging findings

OBJECTIVE

To document the imaging findings of hepatic cavernous hemangioma detected in cirrhotic liver.

MATERIALS AND METHODS

The imaging findings of 14 hepatic cavernous hemangiomas in ten patients with liver cirrhosis were retrospectively analyzed. A diagnosis of hepatic cavernous hemangioma was based on the findings of two or more of the following imaging studies: MR, including contrast-enhanced dynamic imaging (n = 10), dynamic CT (n = 4), hepatic arteriography (n = 9), and US (n = 10).

RESULTS

The mean size of the 14 hepatic hemangiomas was 0.9 (range, 0.5-1.5) cm in the longest dimension. In 11 of these (79%), contrast-enhanced dynamic CT and MR imaging showed rapid contrast enhancement of the entire lesion during the early phase, and hepatic arteriography revealed globular enhancement and rapid filling-in. On contrast-enhanced MR images, three lesions (21%) showed partial enhancement until the 5-min delayed phases. US indicated that while three slowly enhancing lesions were homogeneously hyperechoic, 9 (82%) of 11 showing rapid enhancement were not delineated.

CONCLUSION

The majority of hepatic cavernous hemangiomas detected in cirrhotic liver are small in size, and in many, hepatic arteriography and/or contrast-enhanced dynamic CT and MR imaging demonstrates rapid enhancement. US, however, fails to distinguish a lesion of this kind from its cirrhotic background.

Cloning and expression of the VP1 major capsid protein of diabetogenic encephalomyocarditis (EMC) virus and prevention of EMC virus-induced diabetes by immunization with the recombinant VP1 protein

The development of diabetes in mice induced by encephalomyocarditis (EMC) virus provides the best experimental evidence that viruses have an aetiological role in the pathogenesis of this disease. The major capsid protein (VP1) of EMC virus is important for both the attachment of the virus to pancreatic beta cells and for the determination of antigenicity. This experiment was initiated to clone the gene for the major capsid protein, VP1, of the diabetogenic EMC (EMC-D) virus, express the VP1 protein, and test whether the recombinant VP1 protein can prevent development of EMC-D virus-induced diabetes in mice. We successfully cloned the VP1 gene of the EMC-D virus in the expression vector pRSET and subsequently expressed the protein in Escherichia coli. The recombinant VP1 protein was then purified by affinity chromatography. Five- to six-week-old male SJL/J mice were immunized intraperitoneally with purified VP1 protein and then challenged after various intervals with highly diabetogenic EMC-D virus. None of the VP1-immunized mice developed diabetes, irrespective of the interval between immunization and virus challenge, whereas 80 to 95% of the EMC-D virus-infected control mice did develop diabetes. All of the VP1-immunized mice showed intact pancreatic islet architecture, whereas most of the infected control mice showed severe beta cell necrosis and lymphocytic infiltration of their pancreatic islets. On the basis of these observations, we conclude that the recombinant VP1 protein of EMC-D virus can completely prevent the development of EMC-D virus-induced diabetes in mice.

Adrenocorticotropin receptor/melanocortin receptor-2 maps within a reported susceptibility region for bipolar illness on chromosome 18

We have examined the possible linkage of adrenocorticotropin receptor/melanocortin receptor-2 (ACTHR/MC-2) to a reported putative susceptibility locus for bipolar illness (BP) in 20 affected pedigrees. Initially, allelic variants of the gene were identified by polymerase chain reaction-single stranded conformation polymorphism (PCR-SSCP) and the gene was genetically mapped using both the Centre d'Etudes du Polymorphisme Humain (CEPH) pedigrees and the BP pedigrees used in this study. We found that the ACTHR/MC-2 gene maps between D18S53 and D18S66. These loci span a region of chromosome 18 which, in a previous study [Berrettini et al.: Proc Natl Acad Sci USA 91:5918-5921, 1994) revealed a putative predisposing locus to BP through nonparametric methods of linkage analysis. Linkage of ACTHR/MC-2 to BP was not demonstrable under parametric and nonparametric methods of analyses, although affected sib-pair (ASP) method revealed an increase in allele sharing among ill individuals, P = 0.023. Since this receptor is within a potential linkage region, ACTHR/MC-2 could be considered a candidate gene for BP.

Multiple minute digitate hyperkeratoses

A 56-year-old man had multiple minute digitate hyperkeratosis. His clinical and histological findings are compatible with those of the only other case reported in the literature.