[en] Recently, the manipulation of a single cell has been receiving much attention in transgenesis, in-vitro fertilization, individual cell based diagnosis, and pharmaceutical applications. As these techniques require precise injection and manipulation of cells, issues related to penetration force arise. In this work the penetration force of living cell was studied using an atomic force microscope (AFM). L929, HeLa, 4T1, and TA3 HA II cells were used for the experiments. The results showed that the penetration force was in the range of 2∼22 nN. It was also found that location of cell penetration and stiffness of the AFM cantilever affected the penetration force significantly. Furthermore, double penetration events could be detected, due to the multi-membrane layers of the cell. The findings of this work are expected to aid in the development of precision micro-medical instruments for cell manipulation and treatment

[en] The NiSO_4 supported on FeO-promoted ZrO_2 catalysts were prepared by the impregnation method. FeOpromoted ZrO_2 was prepared by the coprecipitation method using a mixed aqueous solution of zirconium oxychloride and iron nitrate solution followed by adding an aqueous ammonia solution. The addition of nickel sulfate (or FeO) to ZrO_2 shifted the phase transition of ZrO_2 (from amorphous to tetragonal) to higher temperatures because of the interaction between nickel sulfate (or FeO) and ZrO_2. 10-NiSO_4/5-FeO-ZrO_2 containing 10 wt % NiSO_4 and 5 mol % FeO, and calcined at 500 .deg. C exhibited a maximum catalytic activity for ethylene dimerization. NiSO_4/FeO-ZrO_2 catalysts was very effective for ethylene dimerization even at room temperature, but FeO-ZrO_2 without NiSO_4 did not exhibit any catalytic activity at all. The catalytic activities were correlated with the acidity of catalysts measured by the ammonia chemisorption method. The addition of FeO up to 5 mol % enhanced the acidity, surface area, thermal property, and catalytic activities of catalysts gradually, due to the interaction between FeO and ZrO_2 and due to consequent formation of Fe-O-Zr bond

[en] The author studied the magnification ratio of teeth length in orthopantomogram through intraoral film taken by standardized paralleling technique. In this study, intraoral radiograph and orthopantomogram were taken in 2 cases of dry skull and 36 adults (504 teeth). The obtained results were as follows: 1. In case of dry skull, the magnification ratio of standard films was 4.6% to 5.9% and that of Orthopantomograph 5 was 15.1% to 33.1%. The magnification ratio of to the standard film was 9.2% to 26.5%. 2. In case of adults, the magnification ratio Orthopantomograph 5 to the standard films was 9.5% to 24.6%. 3. There were no significant difference in magnification between left and right. 4. Anterior teeth had lesser magnification than teeth. 5. It was considered that teeth length showed in Orthopantomograph 5 was magnified 15.4% to 31.3% than actual teeth length.

[en] The author observed the changes of vasculature of pre-and post-irradiation on DMBA induced rat tongue cancer. The study was performed by using vascular corrosion resin casting, and scanning electron microscopy. The results were as follows. 1. The capillaries runned parallely and formed bundles and, sometimes, plexus. The endothelial cells were arranged regularly and small pores were observed. 2. In irradiated normal tongue the capillaries were curved slightly and formed plexus on initial day of post-irradiation. On third day the capillaries and capillary pores were dilated and the endothelial cell arrangement was irregular. The effects of irradiation were gradually increased from initial to the 3rd day, though it was decreased after 7th day. 3. The vasculature of DMBA induced tongue cancer group were very irregular, and large avascular lesions were formed according to the cancer necrosis or tumor cell nest and the vasculature was narrowed and paralleled around the avascular lesion by compression of cancer cell nest. The vascular wall was roughened and dilated, forming club shaped or varix. 4. The vessels were curved and formed reticular network in irradiated DMBA induced tongue carinoma group. The free end of newly formed capillaries had regular width, and also irregular club shaped or aneurysmal dilation were observed. The vascular structures were destroyed and vessels were fused in tumor necrosis lesion. The radiation effects were marked on the first and third day of irradiation and the effects were decreased after seventh day and showed capillary regeneration.

[en] (001) oriented (Ba,Sr)TiO₃ (BST) and (Sr,Ba)Nb₂O₆ (SBN) thin films were deposited on MgO (001) single crystal substrates by the pulsed laser deposition method. Structural properties of BST and SBN films were investigated by using an X-ray diffractometer. Coplanar waveguide (CPW) devices based on BST/MgO and SBN/MgO layer structure were fabricated by dc sputtering deposition, photolithography, and etching processes. To compare the microwave performance of the CPW phase shifters based on (001) oriented BST and SBN films, CPW devices having various gaps and widths were fabricated. The device characteristics in the microwave region were examined by measuring the scattering parameter obtained by using a HP 8510C vector network analyzer with the frequency range 0.5 ∼ 20 GHz at room temperature under the dc bias variation of 0 ∼ 40 V. The measured return loss and insertion loss at 10 GHz were about - 15 ∼ - 8 dB and - 5 ∼ - 2 dB, which mainly depended on the impedances of the CPW transmission lines, which were determined from the dielectric constant of the constituent materials and geometrical factors of the device. The measured differential phase shifts were about 34 .deg. ∼ 49 .deg. at 10 GHz with 40 V dc bias variation, which depended on the geometrical factors of the device and ferroelectric film characteristics.

[en] To evaluate the inter-group differences in growth and the pathological results of nodular ground-glass opacities (GGOs) according to their size and focal solid portions. Ninety-six nodular GGOs in 55 individuals followed by CT for at least one month from an initial chest CT were included. Forty nodular GGOs in 30 individuals were pathologically confirmed to be: adenocarcinoma (n 15), bronchioloalveolar carcinoma (BAC) (n = 11), atypical adenomatous hyperplasia (AAH) (n = 8), focal interstitial fibrosis (n = 5) and aspergillosis (n = 1). Lesions were categorized based on high-resolution CT findings: pure nodular GGO (PNGGO) ≤10 mm, PNGGO > 10 mm, mixed nodular GGO (MNGGO) ≤ 10 mm, and MNGGO > 10 mm. In each group, the change in size during the follow- up period, the pathological results and the rate of malignancy were evaluated. Three MNGGO lesions, and none of the PNGGO, grew during the follow- up period. Resected PNGGOs 10 mm were AAH (n = 6), BAC (n = 5), and focal interstitial fibrosis (n = 1). Resected PNGGOs > 10 mm were focal interstitial fibrosis (n = 4), AAH (n = 2), BAC (n = 2), and adenocarcinoma (n = 2). Resected MNGGOs ≤ 10 mm were adenocarcinoma (n 2), and BAC (n = 1). Resected MNGGOs > 10 mm were adenocarcinoma (n = 11), BAC (n = 3), and aspergillosis (n = 1). Mixed nodular GGOs (MNGGOs) had the potential for growth; most were pathologically adenocarcinoma or BAC. By contrast, PNGGOs were stable for several months to years; most were AAH, BAC, or focal interstitial fibrosis

[en] We evaluated treatment outcomes of thymic carcinomas to determine prognostic factors for survival. Between May 1988 and May 2009, 41 patients had pathologic diagnosis of thymic carcinoma in Seoul National University Hospital, Seoul, Korea. Of these, 40 patients were followed up to 188 months after treatment. The mean age of all patients was 58.3 years and male to female ratio was 23 to 17. Among 30 patients who underwent surgical resection, 26 achieved R0 resection and postoperative radiotherapy (PORT) was performed in 22 patients (73%). Various chemotherapeutic regimens were given with local treatment modalities, surgery and/or radiotherapy, in 12 patients. The 5-year locoregional control (LRC), distant metastasis-free survival, progression-free survival (PFS), and overall survival were 79.4%, 53.0%, 42.6%, and 63.6%, respectively. Patients with Masaoka stage I or II showed excellent prognosis of 5-year PFS around 90%. In advanced stages, invasion of the great vessels or atrium by thymic carcinomas was negative prognostic factor for PFS in univariate analysis. Lymph node involvement was statistically significant factor for LRC and PFS. Local or regional recurrence was infrequent after surgical resection followed by PORT, while distant metastasis was the major component of treatment failure. Complete resection followed by PORT provided remarkable local control without severe acute toxicities in patients with stage II and favorable stage III thymic carcinoma. Invasion of the great vessels or atrium was statistically significant prognostic factor for PFS.

[en] This study aimed to compare the diagnostic value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and magnetic resonance imaging (MRI) in the preoperative evaluation of uterine carcinosarcoma. Fifty-four women with pathologically confirmed uterine carcinosarcoma who underwent preoperative FDG PET/CT and MRI from June 2006 to November 2016 were included. Pathologic findings from primary tumor lesions, para-aortic and pelvic lymph node (LN) areas, and peritoneal seeding lesions were compared with the FDG PET/CT and MRI findings. The maximum standardized uptake value (SUVmax) of the primary tumor and LN was obtained. The tumor-to-liver ratio (TLR) was calculated by dividing the SUVmax of the primary tumor or LN by the mean SUV of the liver. For detecting primary tumor lesions (n = 54), the sensitivity and accuracy of FDG PET/CT (53/54) and MRI (53/54) were 98.2%. The sensitivity, specificity, and accuracy of FDG PET/CT versus MRI were as follows: 63.2% (12/19) versus 26.3% (5/19), 100% (35/35) versus 100% (35/35), and 87.0% versus 74.0%, respectively, for pelvic LN areas (p = 0.016); 85.7% (12/14) versus 42.9% (6/14), 90% (36/40) versus 97.5% (39/40), and 88.9% versus 83.3%, respectively, for para-aortic LN areas (p = 0.004); and 59.4% (19/32) versus 50% (16/32), 100% (22/22) versus 100% (22/22), and 75.9% versus 70.4%, respectively, for peritoneal seeding lesions (p = 0.250). For distant metastasis, the sensitivity, specificity, and accuracy of FDG PET/CT were 100 (8/8), 97.8 (45/46), and 98.2%, respectively. FDG PET/CT showed superior diagnostic accuracy compared to MRI in detecting pelvic and para-aortic LN metastasis in patients with uterine carcinosarcoma. Moreover, FDG PET/CT facilitated the identification of distant metastasis

[en] A previously healthy, non-smoking, 72-year-old woman was referred to our hospital with abnormal chest X-ray and chest discomfort. A 3.5-cm, well-defined, right paratracheal mass was revealed on non-contrast chest computed tomography (CT), which was suspected to be an azygous vein aneurysm, lymph adenopathy or neurogenic tumor. Whole-body integrated positron emission tomography/magnetic resonance imaging (PET/MRI) (Biograph mMR; Siemens Healthcare, Erlangen, Germany) was performed for the differential diagnosis. A homogenously enhancing mass connected with the azygous vein was well visualized in a post-contrast volumetric interpolated gradient echo (VIBE) sequence. Additionally, the PET showed minimal ¹⁸F-fluorodeoxyglucose (FDG) uptake (maximum standardized uptake value [SUVmax], 1.83), similar to that of the great vessels, with no filling defect to suggest thromboembolism and no significant FDG uptake to suggest active thrombo-embolism or malignancy. The imaging findings in integrated PET/MRI were useful to characterize azygous vein aneurysm. The patient had a video-assisted thoracoscopic surgery to relieve the symptom of chest pain. A congenital etiology of azygous vein aneurysm was confirmed by pathology

[en] Current injected into an electrically conducting object induces distributions of magnetic flux density as well as voltage and current density. In magnetic resonance electrical impedance tomography (MREIT), we measure the induced magnetic flux density using an MRI scanner to reconstruct cross-sectional conductivity images of the object. The current injection must be synchronized with a chosen MRI pulse sequence and the current source needs to be programmable to accommodate various pulse sequences. For an injected current of 1 mA, for example, we may expect an induced magnetic flux density of a few nanoteslas, and noise reduction in measured magnetic flux density data is important for better conductivity image quality. In this paper, we describe how to reduce noise in measured magnetic flux density data based on analyses of noise sources in MREIT. Given an MRI scanner and an imaging object, we found that the current source including lead wires becomes a major noise source. We designed a low-noise programmable current source with optical links, batteries and electromagnetic shields. Equipped with lead switching capability, it automates MREIT imaging experiments using multiple pairs of electrodes. We found that the new current source improves the output current SNR by about 10 dB and the MR magnitude image SNR by about 30%. Placing it near an imaging object inside the shielded room, we could reduce the noise standard deviation in measured magnetic flux density data by 40%. We propose use of this low-noise current source for in vivo animal and human MREIT imaging studies