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Color dye-doped silk fibroin nanoparticles were successfully fabricated using a microemulsion method. An aqueous silk fibroin solution was prepared by dissolving cocoons (Bombyx mori) in a concentrated lithium bromide solution followed by dialysis. A color dye solution was also mixed with the aqueous silk fibroin solution. The surfactants used for the microemulsion were then removed by methanol and ethanol, yielding color dye-doped silk fibroin nanoparticles, approximately 167 nm in diameter. The secondary structure of the nanoparticles showed a β-sheet conformation, as characterized by Fourier transform infrared spectroscopy. The morphology of the nanoparticles was determined by field emission scanning electron microscopy, transmission electron microscopy and atomic force microscopy, and their size and size distribution were measured by dynamic light scattering. The color dye-doped silk fibroin nanoparticles were examined by confocal laser scanning microscopy.

Many mitotic kinases have been targeted for the development of anti-cancer drugs, and inhibitors of these kinases have been expected to perform well for cancer therapy. Efforts focused on selecting good targets and finding specific drugs to target are especially needed, largely due to the increased frequency of anti-cancer drugs used in the treatment of lung cancer. Vaccinia-related kinase 1 (VRK1) is a master regulator in lung adenocarcinoma and is considered a key molecule in the adaptive pathway, which mainly controls cell survival. We found that ursolic acid (UA) inhibits the catalytic activity of VRK1 via direct binding to the catalytic domain of VRK1. UA weakens surveillance mechanisms by blocking 53BP1 foci formation induced by VRK1 in lung cancer cells, and possesses synergistic anti-cancer effects with DNA damaging drugs. Taken together, UA can be a good anti-cancer agent for targeted therapy or combination therapy with DNA damaging drugs for lung cancer patients.

Many mitotic kinases have been targeted for the development of anti-cancer drugs and inhibitors of these kinases have been expected to perform well for cancer therapy. Efforts focused on selecting good targets and finding specific drugs to target are especially needed, largely due to the increased frequency of anti-cancer drugs used in the treatment of lung cancer. Vaccinia-related kinase 1 (VRK1) is a master regulator in lung adenocarcinoma and is considered a key molecule in the adaptive pathway, which mainly controls cell survival. We found that ursolic acid (UA) inhibits the catalytic activity of VRK1 via direct binding to the catalytic domain of VRK1. UA weakens surveillance mechanisms by blocking 53BP1 foci formation induced by VRK1 in lung cancer cells and possesses synergistic anti-cancer effects with DNA damaging drugs. Taken together, UA can be a good anti-cancer agent for targeted therapy or combination therapy with DNA damaging drugs for lung cancer patients.

Dear Editor: Unilateral nevoid telangiectasia (UNT) syndrome is a rare vascular dermatosis, characterized by areas of superficial telangiectases distributed in a dermatomal, unilateral pattern usually on the upper trunk and extremities. The etiopathogenesis is not completely understood, but the most widely accepted theory is its association with hyperestrogenic condition1. Herein, we report a rare case of UNT accompanied by liver metastasis of colon cancer. A 26-year-old male presented with progressive asymptomatic erythematous telangiectactic patches localized to the left chest and abdomen of 5-month duration. Three months after from when he had noticed skin lesions, he was diagnosed with colon cancer with multiple metastases at lumbar spine, lung, intra-abdominal lymph nodes including the liver and started chemotherapy following the FOLFIRI (fluorouracil, leucovorin, and irinotecan) regimen. He had no history of hepatitis or alcoholism. No family members were known to have any similar condition. On physical examination, there were no palmar erythema, ascites, or hepatosplenomegaly suggestive of chronic liver disease. On examination of the skin, erythematous telangiectactic patches on the left chest and abdomen involving dermatomes C3-4 and T4-10 were observed (Fig. 1). Biopsy specimen of the skin revealed intact epidermis with thin-walled capillaries in the superficial dermis (Fig. 2). Immunohistochemical staining was negative for estrogen, progesterone, and vascular endothelial growth factor (VEGF) receptors. Laboratory investigations were within normal range including liver function test. However, circulating estrogen level (155.55 pg/ml; normal range, 40~115 pg/ml) and serum carcinoembryonic antigen level (329.50 ng/ml; normal range, 0~4.7 ng/ml), which may be due to colon cancer and multiple metastases. Based on clinical and histopathologic findings, a diagnosis of UNT syndrome accompanied by liver metastasis of colon cancer was made. Reported cases of UNT syndrome mostly occur in women during pregnancy or puberty and in men with alcoholic cirrhosis2. Rarely, it has also been described in patients with carcinoid tumor of stomach with liver metastasis3. Several cases reported in recent years have cast doubt on the view that estrogen is the causal agent of telangiectasia development because of normal estrogen levels or negative estrogen and progesterone receptors1,4. Turan et al.4 suggested that VEGF may play a role in the pathogenesis of UNT syndrome in patients with underlying hepatic disease. On the other hand, Smith et al.5 reported a case of UNT syndrome accompanied by chronic hepatitis C virus infection, with a normal serum estrogen profile and VEGF level but strong positive immunohistochemical staining of lesional skin with VEGF. They suggested this result supports the hypothesis that angiogenic factors play a role in the pathogenesis of UNT syndrome. VEGF is already known to be a commonly expressed angiogenic factor in human colorectal cancer metastases and high serum VEGF level is correlated with colon cancer liver metastasis. Despite being unable to check serum VEGF level, elevated estrogen and VEGF levels could be related to the pathogenesis of UNT syndrome in our patient who had colon cancer with multiple metastases including the liver. To our knowledge, this is the first report of UNT syndrome accompanied by liver metastasis of colon cancer. Fig. 1 (A) Multiple erythematous telangiectactic patches localized to left chest (12×8 cm sized). (B) abdomen (27×21 cm sized). Fig. 2 Normal epidermis with dilated thin-walled capillaries in the superficial dermis (H&E, ×100).

Image evaluation is necessary in digital radiography (DR) which is widely used in medical imaging. Among parameters of image evaluation, modulation transfer function (MTF) is the important factor in the field of medical imaging and necessary to obtain detective quantum efficiency (DQE) which represents overall performance of the detector signal-to-noise ratio. However, the accurate measurement of MTF is still not easy because of geometric effect, electric noise, quantum noise, and truncation error. Therefore, in order to improve accuracy of MTF, four experimental methods were tested in this study such as changing the tube current, applying smoothing method in edge spread function (ESF), adjusting line spread function (LSF) range, and changing tube angle. Our results showed that MTF’s fluctuation was decreased by high tube current and smoothing method. However, tube current should not exceed detector saturation and smoothing in ESF causes a distortion in ESF and MTF. In addition, decreasing LSF range diminished fluctuation and the number of sampling in MTF and high tube angle generates degradation in MTF. Based on these results, excessively low tube current and the smoothing method should be avoided. Also, optimal range of LSF considering reduction of fluctuation and the number of sampling in MTF was necessary and precise tube angle is essential to obtain an accurate MTF. In conclusion, our results demonstrated that accurate MTF can be acquired.

Algorithmic system modeling which includes a geometric motion of source, phantom, and detector for reconstructing the tomographic images is well-known in medical imaging field. Especially in a digital X-ray tomosynthesis system (DTS) which scans an object in limited angle, not a full 360-degree, an accurate system modeling should be derived to reconstruct an excellent cross sectional image. In this study, we analytically modeled a ray-driven forward projector and a pixel-driven back-projector. We firstly acquired forward projected images of a computerized Shepp-Logan phantom over an ±20° angular range using ray-driven projector. On top of that, we reconstructed the analytically scanned phantom using pixel-driven back-projector based on a conventional filtered back-projection (FBP) in tomosynthesis. We evaluated root-mean-square errors (RMSEs) and horizontal profiles of normalized pixel values in the reconstructed axial cross sectional images. The results indicated that pixel-driven back-projector combined with ray-driven projector showed low RMSEs of 0.25, 0.49, 0.80, 1.46, and 0.94 among five different regions-of-interests (ROIs). Illustrated horizontal profiles of normalized pixel values between the referenced phantom and reconstructed object showed similar values, which demonstrated that both ray- and pixel-driven projector/back-projector could be utilized in linear motion DTS.

Epithelial-mesenchymal transition (EMT) is an important process appearing in embryo development and tumor migration or progression, which is influenced by 17β-estradiol (E2). Bisphenol A (BPA) and nonylphenol (NP) are suspected as endocrine disrupting chemicals (EDCs) because they can exert estrogenic properties. In this study, we examined whether E2, BPA, and NP can lead to the EMT process in BG-1 ovarian cancer cells expressing estrogen receptors (ERs). To confirm the effect of E2, BPA, and NP, BG-1 cells were cultured under treatment with E2, BPA, or NP, and the alteration of EMT markers such as vimentin was examined at mRNA levels by using real-time and reverse-transcription (RT)-PCR. The expressions of snail, slug, and vimentin were enhanced by the treatment of E2, BPA, or NP compared to a control (DMSO). In protein levels, vimentin protein was increased by E2 and two EDCs, while E-cadherin was decreased. In addition, the expression of snail protein was enhanced by the treatment of E2 and the two EDCs in comparison with that of the control. Since EMT response in cancer cells can affect metastasis, we also performed a scratch assay and Western blot assay to show the migration ability caused by E2, BPA, or NP. Consequently, E2, BPA, and NP enhanced the migration capability of BG-1 cells and increased the expression of MMP-9 protein. Furthermore, to examine whether EMT and migration of BG-1 cancer cells are induced by BPA or NP via the ER dependent pathway, we cotreated the cells with ER-antagonist, ICI 182,780, in the presence of E2, BPA, or NP. As a result, the expressions of E-cadherin, vimentin, snail, and slug were reversed following treatment with an ER antagonist. Moreover, we confirmed that ICI 182,780 reduced the migration ability of BPA and NP to the control level. Taken together, these results indicate that BPA and NP, the potential EDCs, may have the ability to influence ovarian cancer metastasis via regulating EMT markers and migration in ER-expressing BG-1 ovarian cancer cells.

The production of gas gaps, the core components of the Forward RPCs in the CMS experiment, has reached a mature stage of the production stream. A total of 360 gas gaps, equivalent to 120 RPCs, has been manufactured, tested for quality control, and delivered to CERN in Switzerland and to Pakistan, where the complete Forward RPCs are being assembled. In this paper, the layout of the gas gaps, the production procedures, facilities, and the selection process of the qualified gas gaps are presented.

We present the detailed analysis of the time and charge signals of a prototype double gap resistive plate chamber for the endcap region of the compact muon solenoid detector at CERN LHC. We demonstrate that the operating high-voltage plateau can be extended at least up to 400 V with the present design. The simple avalanche multiplication model can reproduce the experimental charge spectra reasonably well at the beginning of the high-voltage plateau region. The effective Townsend coefficient is estimated in the avalanche mode operation.

The Compact Muon Solenoid (CMS) forward resistivity plate chambers (RPCs) at the high eta region must be operated in presence of a radiation-induced rate as high as 1 kHz / cm 2 . It is still unknown if the RPCs coated with linseed oil can be operated under such a high-radiation environment over the lifetime of CMS. Non-oiled RPCs may be one of the options since phenolic or melamine-coated bakelite is chemically stabler than linseed oil. We have constructed oiled and non-oiled RPCs at the high eta region of CMS using phenolic bakelite and tested them in the Gamma Irradiation Facility at CERN. While both RPCs show the same characteristics in the efficiency and the strip multiplicity, the non-oiled RPC generates an intrinsic noise rate of 50 Hz / cm 2 , compared to only 5 Hz / cm 2 for the oiled RPC, both at 10.0 kV which is about 100 V above the 95 % knee of the efficiency curve.

Strip clusters of muons and background hits induced by gamma rays and spurious pulses are analyzed for the Forward Region Resistive Plate Chamber of the CMS/LHC. In order to perform the analysis, a real size RE2/1 prototype RPC manufactured with the final baseline design of the Forward Region RPCs was tested at the Gamma Irradiation Facility of CERN. Strip cluster sizes for muons and strip cluster rates for gamma rays are sensitive to the threshold setting while the efficiency to muons is relatively insensitive.

Background and purpose The detection of aquaporin 4-IgG (AQP4-IgG) is now a critical diagnostic criterion for neuromyelitis optica spectrum disorder (NMOSD). To evaluate the serostatus of NMOSD patients based on the 2015 new diagnostic criteria using a new in-house cell-based assay (CBA). Methods We generated a stable cell line using internal ribosome entry site-containing bicistronic vectors, which allow the simultaneous expression of two proteins (AQP4 and green fluorescent protein) separately from the same RNA transcript. We performed in-house CBA using serum from 386 patients: 178 NMOSD patients diagnosed according to the new diagnostic criteria without AQP4-IgG, 63 high risk NMOSD patients presenting 1 of the 6 core clinical characteristics of NMOSD but not fulfilling dissemination in space, and 145 patients with other neurological diseases, including 66 with multiple sclerosis. The serostatus of 111 definite and high risk NMOSD patients were also tested using a commercial CBA kit with identical serum to evaluate the correlation between the 2 methods. All assays were performed by two independent and blinded investigators. Results Our in-house assay yielded a specificity of 100% and sensitivities of 80% (142 of 178) and 76% (48 of 63) when detecting definite- and high risk NMOSD patients, respectively. The comparison with the commercial CBA kit revealed a correlation for 102 of the 111 patients: no correlation was present in 7 patients who were seronegative using the commercial method but seropositive using the in-house method, and in 2 patients who were seropositive using the commercial method but seronegative using the in-house method. Conclusions These results demonstrate that our in-house CBA is a highly specific and sensitive method for detecting AQP4-IgG in NMOSD patients.

Palm oil is a common cooking ingredient used in the commercial food industry as the second largest consumed vegetable oil in the world. Because of its lower cost and highly saturated nature, it usually maintains a solid form at room temperature and is used as a cheap substitute for butter. However, there has been a growing health concern about palm oil because of the link between dietary fats and coronary heart disease. Palm oil contains ∼49% saturated fat, a relatively high concentration compared with other vegetable oils. Consequently, high intakes of saturated fat from palm oil induce a larger increase in plasma concentrations of total cholesterol and low-density lipoproteins. In the present study, we examined the hyperlipidemia of palm oil and the risk of cardiovascular disease (CVD) using a rat model in comparison with sunflower oil with a relatively low level of saturated fat. On in vivo examination using Sprague-Dawley (SD) rats for 22 days, there were no significant differences in serum lipid levels, suggesting that palm oil may not cause hyperlipidemia and elevate CVD risk. However, liver samples obtained from SD rats fed with palm oil showed a lot of large lipid inclusions stained with the Oil Red O working solution, but not much lipid accumulation was observed in rats treated with sunflower oil. In addition, lipid accumulation in the mixed oil group fed the combination of palm and sunflower (1:1) oil was shown to be at an intermediary level between the palm oil group and sunflower oil group. Taken together, these results indicate that palm oil, a highly saturated form of vegetable oil, may induce dysfunction of the liver lipid metabolism before affecting serum lipid levels. On the other hand, sunflower oil, a highly unsaturated vegetable oil, was shown to be well metabolized in liver.

There are three types of stem cells: embryonic stem (ES) cells, adult stem (AS) cells and induced pluripotent stem (iPS) cells. These stem cells have many benefits including the potential ability to differentiate into various organs. In addition, engineered stem cells (GESTECs) designed for delivering therapeutic genes may be capable of treating human diseases including malignant cancers. Stem cells have been found to possess the potential for serving as novel delivery vehicles for therapeutic or suicide genes to primary or metastatic cancer formation sites as a part of gene-directed enzyme/prodrug combination therapy (GEPT). Given the advantageous properties of stem cells, tissue-derived stem cells are emerging as a new tool for anticancer therapy combined with prodrugs. In this review, the effects of GESTECs with different origins, i.e., neural, amniotic membrane and amniotic fluid, introduced to treat patients with diverse types of gynecologic and breast cancers are discussed. Data from the literature indicate the therapeutic potential of these cells as a part of gene therapy strategies to selectively target malignancies in women at clinically terminal stages.

Scattered radiation is inevitably generated in the object. The distribution of the scattered radiation is influenced by object thickness, filed size, object-to-detector distance, and primary energy. One of the investigations to measure scatter intensities involves measuring the signal detected under the shadow of the lead discs of a beam-stop array (BSA). The measured scatter by BSA includes not only the scattered radiation within the object (object scatter), but also the external scatter source. The components of external scatter source include the X-ray tube, detector, collimator, x-ray filter, and BSA. Excluding background scattered radiation can be applied to different scanner geometry by simple parameter adjustments without prior knowledge of the scanned object. In this study, a method using BSA to differentiate scatter in phantom (object scatter) from external background was used. Furthermore, this method was applied to BSA algorithm to correct the object scatter. In order to confirm background scattered radiation, we obtained the scatter profiles and scatter fraction (SF) profiles in the directions perpendicular to the chest wall edge (CWE) with and without scattering material. The scatter profiles with and without the scattering material were similar in the region between 127 mm and 228 mm from chest wall. This result indicated that the measured scatter by BSA included background scatter. Moreover, the BSA algorithm with the proposed method could correct the object scatter because the total radiation profiles of object scatter correction corresponded to original image in the region between 127 mm and 228 mm from chest wall. As a result, the BSA method to measure object scatter could be used to remove background scatter. This method could apply for different scanner geometry after background scatter correction. In conclusion, the BSA algorithm with the proposed method is effective to correct object scatter.

In previous study, to improve both sensitivity and spatial resolution, we recommended to use a pixelated parallel-hole collimator with equal hole and pixel sizes based on CdTe pixelated semiconductor SPECT system. However, the tradeoff between sensitivity and spatial resolution is needed before determination of pixelated parallel-hole collimator geometric designs. The detective quantum efficiency (DQE) is a concept which takes both the sensitivity and spatial resolution into account to provide an overall measure and may be better suited for optimization. The purpose of this study was to optimize and evaluate the above-mentioned collimators using DQE to determine the best image performance of CdTe pixelated semiconductor SPECT system. We conducted a simulation study using a Geant4 Application for Tomographic Emission (GATE) simulation. To evaluate the DQE from modulation transfer function (MTF) and sensitivity, the collimator septal heights were varied from 15 to 30 mm in 5 mm increments at step and source-to-collimator distances were 4, 5, 6, and 7 cm. According to the results, the DQE decreased with increasing source-to-collimator distance and septal height. We have presented the evaluation results of pixelated parallel-hole collimators with various geometric designs. In conclusion, we successfully optimized the pixelated parallel-hole collimator, and based on our results, we recommended using lower septal height with smaller source-to-collimator distance with CdTe pixelated semiconductor SPECT system.

Uncontrolled proliferation, a major feature of cancer cells, is often triggered by the malfunction of cell cycle regulators such as protein kinases. Recently, cell cycle-related protein kinases have become attractive targets for anti-cancer therapy, because they play fundamental roles in cellular proliferation. However, the protein kinase-targeted drugs that have been developed so far do not show impressive clinical results and also display severe side effects; therefore, there is undoubtedly a need to investigate new drugs targeting other protein kinases that are critical in cell cycle progression. Vaccinia-related kinase 1 (VRK1) is a mitotic kinase that functions in cell cycle regulation by phosphorylating cell cycle-related substrates such as barrier-to-autointegration factor (BAF), histone H3, and the cAMP response element (CRE)-binding protein (CREB). In our study, we identified luteolin as the inhibitor of VRK1 by screening a small-molecule natural compound library. Here, we evaluated the efficacy of luteolin as a VRK1-targeted inhibitor for developing an effective anti-cancer strategy. We confirmed that luteolin significantly reduces VRK1-mediated phosphorylation of the cell cycle-related substrates BAF and histone H3, and directly interacts with the catalytic domain of VRK1. In addition, luteolin regulates cell cycle progression by modulating VRK1 activity, leading to the suppression of cancer cell proliferation and the induction of apoptosis. Therefore, our study suggests that luteolin-induced VRK1 inhibition may contribute to establish a novel cell cycle-targeted strategy for anti-cancer therapy. Published version

We present the first beam test results of a real size prototype RPC for the endcap region of the CMS, one of large detectors at CERN LHC. The chamber was built with relatively low resistivity bakelite made in Korea and was operated successfully at the Gamma Irradiation Facility at CERN under the highest photon flux available, which corresponds to an effective cluster rate up to about 800 Hz / cm 2 . The cross-talk effects between strips and sectors have been studied extensively. The high voltage plateau, which satisfies the CMS requirements for efficiency and the number of strips fired per cluster, extends to at least 300 V . The time resolution has been measured to be better than 1.3 ns in this HV plateau region. These results demonstrate that the current design of the device can be used as a muon trigger detector for the CMS forward region.

This paper presents the results from cosmic ray tests performed in the framework of R&D effort on the forward Resistive Plate Chamber (RPC) for CMS. A double gapRPC of dimensions 50 � 50 cm 2 with 2 mm gas gaps was tested. We report data on the use of tetrafluorethane-based gas mixture, with additions of water vapour and SF6. Efficiency, time resolution and cross-talk behaviour of the detector were investigated. # 2001 Elsevier Science B.V. All rights reserved. PACS: 29.40.Cs

We present the results from cosmic ray tests on the forward Resistive Plate Chamber (RPC) for the CMS. Double-gap prototype RPC were built and tested in the Korea Detector Laboratory (KODEL). We found that addition of SF 6 and water vapor to the tetrafluorethane-based gas mixture was required for the long-term stable operation of RPC. Efficiency, time resolution as well as cross-talk behavior of the detector were investigated. In addition, we present the temperature and humidity dependence of bulk resistivity of Korean bakelite in detail.

In this report, first beam test results for a real size RE2-2 prototype RPC for the forward region of the CERN CMS are presented. The beam test for the prototype RPC was performed at the Gamma Irradiation Facility (GIF) in CERN with a particle rate ranging up to ∼700 Hz / cm 2 . These test results demonstrate that a real size RE2-2 RPC can be built with relatively low resistivity of bakelite (∼1010 Ω cm). The current design of the RPC can be an option for the CMS forward region with its good efficiency and time characteristics under high radiation environment.

This paper presents data obtained in a systematic study on the bulk resistivity of Korean bakelite as a function of temperature in the range 20–30°C and relative humidity in the range 35–65%. Strong dependence of resistivity on both temperature and humidity was observed. Measurements were carried out in the framework of R&D work on Resistive Plate Chambers (RPCs) which will be used in the CMS detector.

The first real size Resistive Plate Chamber (RPC) prototype of ME2/1 for the forward region of the Compact Muon Solenoid (CMS) detector was constructed at Korea Detector Laboratory (KODEL). The parallel resistive electrodes of the double gap RPC were made of bakelite whose resistivity was 5×10 9 Ω cm . The prototype was tested at the Gamma Irradiation Facility (GIF) of CERN in an environment of the background intensity ranging up to 1 kHz / cm 2 / gap . We report that the full efficiency of 98% has been achieved with time resolution of about 1 ns. These results demonstrate that such a double gap RPC is suitable for the muon trigger in the future experiments.

The first six Resistive Plate Chambers (RPCs) of RE1/1 in the forward region of the Compact Muon Solenoid (CMS) detector were constructed and are being tested. These RPCs cover the pseudo-rapidity region from 1.6 to 2.1 and will serve as the base detector for the CMS RPC muon trigger. We report that these six RPCs are being tested with the CMS RPC quality certification procedures and that a full measurement of a chamber efficiency of 95 ± 4 % has been achieved at an operating voltage of 9.4 kV. This performance demonstrates that the RPC is qualified to be tested at the closest distance to the beam pipe as the muon trigger detector at the full LHC design luminosity.

Recently, we reported that an ethanol extract of Iris nertschinskia induces p53-dependent apoptosis in the MCF7 human breast cancer cell line. However, the detailed mechanisms were not fully explored. Here, we demonstrate another aspect of the activity of I. nertschinskia in breast cancer cells. We compared the response to an ethanol extract of I. nertschinskia in two different human breast cancer cell lines, Hs578Tand MDA-MB231, respectively with relatively low and high AKT1/2 activity by trypan blue exclusion assay and FACS analysis. Knockdown of endogenous AKT1 or AKT2 in breast cancer cells by RNA interference determined the sensitivity to I. nertschinskia ethanol extract compared to control cells. The I. nertschinskia ethanol extract induced cell death in a manner that depended on the level of phosphorylated AKT1/2 protein and was associated with a significant increase in the sub-G1 cell population, indicative of apoptosis. Our results indicate that an ethanol extract of I. nertschinskia differentially induces cell death in breast cancer cells depending on their level of phosphorylated AKT1/2.

The purpose of this study was to investigate the effect of different acquisition parameters and to characterize their relationships in order to improve the detection of microcalcifications using digital breast tomosynthesis (DBT). DBT imaging parameters were optimized using 32 different acquisition sets with six angular ranges (±5°, ±10°, ±13°, ±17°, ±21°, and ±25°) and eight projection views (5, 11, 15, 21, 25, 31, 41, and 51 projections). To investigate the effects of variable angular dose distribution, the acquisition sets were evaluated with delivering more dose toward the central views. Our results show that a wide angular range improved the reconstructed image quality in the z-direction. If a large number of projections are acquired, then electronic noise may dominate the contrast-to-noise ratio (CNR) due to reduced radiation dose per projection. With delivering more dose toward the central views, it was found that the vertical resolution was reduced with increasing dose in the central PVs. On the other hand, the CNR clearly increased with increasing concentration of dose distribution in central views. Although it was found that increasing angular range improved the vertical resolution, it was also found that the image quality of microcalcifications in the in-focus plane did not improve by increasing the noise due to greater effective breast thickness. Angular dose distributions, with more dose delivered to the central views, generally yielded a higher quality factor (QF) than uniform dose distributions.

Background: We examined the relationship between vitamin D status and health-related quality of life, and explored other related factors in the general Korean population. Methods: We used data from the 2007–2012 Korea National Health and Nutrition Examination Survey on 14,104 adults, aged 20–49 years, who had consented to serum vitamin D measurement and answered health-related quality of life questions. EuroQol-5 was used for measurement. Serum vitamin D levels were measured at intervals of 0–9.99, 10–19.99, 20–29.99, and ≥30 ng/mL. Results: Participants with higher serum vitamin D (serum 25-hydroxyvitamin D) levels were significantly less likely to report problems with depression and anxiety. After adjustment for age, gender, income level, education level, marital status, alcohol consumption, smoking status, and the existence of depressive disorders, the odds ratio for reporting a problem with depression and anxiety was 0.60 (95% confidence interval [CI], 0.39–0.91). The odds ratio for the prevalence of any problem was 0.69 (95% CI, 0.53–0.89) before adjustment, but was not statistically significant after adjustment. No significant associations were observed for problems with mobility, self-care, usual activity, or pain and discomfort. Conclusion: This is the first study to examine the associations between vitamin D and health-related quality of life for the general Korean population. Vitamin D status was not significantly associated with the dimensions of EuroQol-5 except for depression and anxiety problems.

Dear Editor: Erythrodermic psoriasis is a severe form of psoriasis, presenting as prominent erythema rather than thick scales, affecting the entirebody including the face, trunk, extremities, and nails. The disease poses a therapeutic challenge, and numerous treatment choices have been examined1. Ustekinumab (Stelara; Jannssen Biotech Inc., Horsham, PA, USA) is a human monoclonal antibody targeting the p40 subunit shared by interleukin (IL)-12 and IL-23. This biological agent has shown good efficacy against plaque-type psoriasis and emerging effectiveness in a variety of inflammatory skin diseases such as atopic dermatitis2. Erythrodermic psoriasis has been an exclusion criterion in studies evaluating the efficacy of ustekinumab for psoriasis, but recently, a few reports have proven its efficacy in treating erythrodermic psoriasis3,4,5. Herein, we report 2 cases of erythrodermic psoriasis that successfully improved following ustekinumab treatment. A 42-year-old man presented with a 7-year history of erythrodermic psoriasis and a 5-year history of psoriatic arthritis. He was previously treated with cyclosporine A, methotrexate, and narrow band ultraviolet B phototherapy. The treatments were interrupted due to liver enzyme elevation and low efficacy. The patient was treated with ustekinumab 45 mg subcutaneously at 0, week 4, and every 12 weeks thereafter. The patient was also diagnosed with latent pulmonary tuberculosis by the QuantiFERON-TB Gold In-Tube test (Cellestis Limited, Carnegie, VIC, Australia). He was concurrently treated with isoniazid 300 mg/day for 6 months and has not experienced a recurrence of tuberculosis to date. At week 28, his Psoriasis Area and Severity Index (PASI) score decreased from 64.8 (baseline) to 9.6 (Fig. 1). The psoriasis aggravated temporarily during discontinuation of the treatment for 5 months and he promptly recovered upon restarting ustekinumab injections. His arthritis symptoms improved slightly, but the improvement was not sufficient for him to stop taking oral sulfasalazine and steroid for the arthralgia. Fig. 1 A 42-year-old man presented with whole body erythema with scanty scales. He responded well to ustekinumab (A: baseline, B: 28 weeks after the treatment, C: 76 weeks after the treatment). The second case is a 26-year-old man suffering from erythrodermic psoriasis for 10 years. Therapies with conventional systemic agents and anti-tumornecrosis factor were discontinued due to lack of efficacy. Four months after the first administration of ustekinumab (45 mg), the patient achieved 75% improvement of the PASI score from 50.9 (baseline) to 4.4 (Fig. 2A, B). Currently, the patient has received treatment for 112 weeks, and is maintaining a PASI 90 improvement (Fig. 2C). Fig. 2 A 26-year-old man. (A) Baseline: normal skin islands are noticeable within the diffuse erythroderma. Clinical improvement was significant and sustained (B) 28 weeks after the treatment and (C) 112 weeks after the treatment, respectively. Both patients are currently on treatment, and show sustained responses without any adverse reactions or exacerbations. Although further studies are needed to evaluate the efficacy and safety of ustekinumab, it is likely that ustekinumab can be an effective therapeutic option for patients affected by erythrodermic psoriasis where other treatments have failed.

The pediatric patients are more susceptible to the effects of ionizing radiation than adults. Pediatric patients are smaller, more radiosensitive than adult patients and many cannot stand unassisted. Their characteristics affect the method of imaging projection and how dose is optimized. The purpose of this study was to investigate the effect of various technical parameters for the dose optimization in pediatric chest radiological examinations by evaluating effective dose and effective detective quantum efficiency (eDQE) including the scatter radiation from the object, the blur caused by the focal spot, geometric magnification and detector characteristics. For the tube voltages ranging from 40 to 90 kV in 10 kV increments at the focus-to-detector distance of 100, 110, 120, 150, 180 cm, the eDQE was evaluated at same effective dose. The results showed that the eDQE was largest at 60 kVp without and with an anti-scatter grid. Especially, the eDQE was considerably higher without the use of an anti-scatter grid on equivalent effective dose. This indicates that the reducing the scatter radiation did not compensate for the loss of absorbed effective photons in the grid. When the grid is not used the eDQE increased with increasing focus-to-detector distance because of the greater effective modulation transfer function (eMTF) with the lower focal spot blurring. In conclusion, for pediatric patients, the amount of scattered radiation is less, and the amount of grid attenuation increased unnecessary radiation dose.

The dual-energy computed tomography (CT) techniques can be adopted to separate the materials having similar Houndsfield Unit (HU) value such as tissues. In the technique, CT image values can be described as effective atomic number and electron density using the dual-energy equation. In this work, we measured effective atomic number and electron density using dual-energy CT images and assessed the image quality in vascular application. For the effective atomic number assessment, the measurements of a Polymethyl methacrylate (PMMA) and water demonstrated small discrepancies of 3.28 % and 5.56 %, respectively. For electron density measurement, the experimental errors of PMMA and water were 7.83 % and 4.00 %, respectively. The trend obtained when comparing the HU values and absolute values such as effective atomic number and electron density demonstrates that the CNR of the HU values is higher than that of the absolute values such as effective atomic number and electron density. With contrast media having low concentration, it is remarkable that the effective atomic number image occasionally has higher CNR values than the HU images. In this study, small discrepancies between the experimental values and known values were obtained. The CNR values provided meaningful results for the absolute measurements in a dual-energy CT technique.

Chfr, a checkpoint with FHA and RING finger domains, plays an important role in cell cycle progression and tumor suppression. Chfr possesses the E3 ubiquitin ligase activity and stimulates the formation of polyubiquitin chains by Ub-conjugating enzymes, and induces the proteasome-dependent degradation of a number of cellular proteins, including Plk1 and Aurora A. While Chfr is a nuclear protein that functions within the cell nucleus, how Chfr is localized in the nucleus has not been clearly demonstrated. Here, we show that nuclear localization of Chfr is mediated by nuclear localization signal (NLS) sequences. To reveal the signal sequences responsible for nuclear localization, a short lysine-rich stretch (KKK) at amino acid residues 257-259 was replaced with alanine, which completely abolished nuclear localization. Moreover, we show that nuclear localization of Chfr is essential for its checkpoint function but not for its stability. Thus, our results suggest that NLS-mediated nuclear localization of Chfr leads to its accumulation within the nucleus, which may be important in the regulation of Chfr activation and Chfr-mediated cellular processes, including cell cycle progression and tumor suppression.

Objectives: The purpose of this study was to examine mothers' eating behavior and salty taste and its relationship to their preschool children's eating behaviors. Methods: This survey was conducted by self-report after getting permission from sixty one mothers who had preschool children. The questionnaire was focused on mothers' salty test and salt-related eating behavior of both mothers and their preschool children. Results: Comparison of eating behavior score between mother and their preschoolers showed that mothers' score was lower than their preschoolers' one. Salty foods with high preference and intake frequency by mothers and preschoolers were 'salted dry fish, stock fish' and 'soup, stew, noodle soup'. In addition, there were strong positive correlations between preference and intake frequency on most of the salty food items. Intake of Ramen soup was significantly different (p < 0.001) between the two groups. Preschoolers ate less ramen soup compared to their mothers. Conclusions: Overall results showed that preschoolers' dietary behavior was better than the mothers' one. However, preschoolers' dietary behavior was significantly influenced by their mothers. Therefore, mothers should have an appropriate eating behavior in order to have a positive influence on their children's eating habits. In addition, the results suggested that proper nutrition education is needed for mothers of preschool

The epithelial-mesenchymal transition (EMT) is important for embryonic development and the formation of various tissues or organs. However, EMT dysfunction in normal cells leads to diseases, such as cancer or fibrosis. During the EMT, epithelial cells are converted into more invasive and active mesenchymal cells. E-box-binding proteins, including Snail, ZEB and helix-loop-helix family members, serve as EMT-activating transcription factors. These transcription factors repress the expression of epithelial markers, for example, E-cadherin, rearrange the cytoskeleton and promote the expression of mesenchymal markers, such as vimentin, fibronectin and other EMT-activating transcription factors. Signaling pathways that induce EMT, including transforming growth factor-β, Wnt/glycogen synthase kinase-3β, Notch and receptor tyrosine kinase signaling pathways, interact with each other for the regulation of this process. Although the mechanism(s) underlying EMT in cancer or embryonic development have been identified, the mechanism(s) in embryonic stem cells (ESCs) remain unclear. In this review, we describe the underlying mechanisms of important EMT factors, indicating a precise role for EMT in ESCs, and characterize the relationship between EMT and ESCs.

Recently, digital breast tomosynthesis (DBT) has been investigated to overcome the limitation of conventional mammography for overlapping anatomical structures and high patient dose with cone-beam computed tomography (CBCT). However incomplete sampling due to limited angle leads to interference on the neighboring slices. Many studies have investigated to reduce artifacts such as interference. Moreover, appropriate filters for tomosynthesis have been researched to solve artifacts resulted from incomplete sampling. The primary purpose of this study is finding appropriate filter scheme with FBP reconstruction for DBT system to reduce artifacts. In this study, we investigated characteristics of various filter schemes with simulation and prototype digital breast tomosynthesis under same acquisition parameters and conditions. We evaluated artifacts and noise with profiles and COV (coefficinet of variation) to study characteristic of filter. As a result, the noise with parameter 0.25 of Spectral filter reduced by 10% in comparison to that with only Ramp-lak filter. Because unbalance of information reduced with decreasing B of Slice thickness filter, artifacts caused by incomplete sampling reduced. In conclusion, we confirmed basic characteristics of filter operations and improvement of image quality by appropriate filter scheme. The results of this study can be utilized as base in research and development of DBT system by providing information that is about noise and artifacts depend on various filter schemes.

Dedicated single-photon emission computed tomography (SPECT) systems based on pixelated semiconductors are being developed for studying small animal models of human disease. To clarify the possibility of using a SPECT system with CdTe for a high resolution low-dose small animal imaging, we compared the quality of reconstructed images from pixelated CdTe detector to those from a small SPECT system with NaI(Tl). The CdTe detector was 44.8×44.8 mm and the pixels were 0.35×0.35×5 mm. The intrinsic resolution of the detector was 0.35 mm, which is equal to the pixel size. GATE simulations were performed to assess the image quality of both SPECT systems. The spatial resolutions and sensitivities for both systems were evaluated using a 10 MBq 99m Tc point source. The quantitative comparison with different injected dose was performed using a voxelized MOBY phantom, and the absorbed doses for each organ were evaluated. The spatial resolution of the SPECT with NaI(Tl) was about 1.54 mm FWHM, while that of the SPECT with a CdTe detector was about 1.32 mm FWHM at 30 mm. The sensitivity of NaI(Tl) based SPECT was 83 cps/MBq, while that of the CdTe detector based SPECT was 116 cps/MBq at 30 mm. The image statistics were evaluated by calculating the CNR of the image from both systems. When the injected activity for the striatum in the mouse brain was 160 Bq/voxel, the CNR of CdTe based SPECT was 2.30 while that of NaI(Tl) based SPECT was 1.85. The CNR of SPECT with CdTe was overall higher than that of the NaI(Tl) based SPECT. In addition, the absorbed dose was higher from SPECT with CdTe than those from NaI(Tl) based SPECT to acquire the same quantitative values. Our simulation results indicated that the SPECT with CdTe detector showed overall high performance compared to the SPECT with NaI(Tl). Even though the validation study is needed, the SPECT system with CdTe detector appeared to be feasible for high resolution low-dose small animal imaging.