[Show abstract][Hide abstract] ABSTRACT: The work function modulation of electrode materials is a crucial factor for achieving superior performance in transparent and flexible device applications. In this work, aluminum-doped zinc-oxide nanoparticles (AZO NPs) with a low work function were introduced in single-wall carbon nanotube (SWCNT) transparent electrodes to achieve an Ohmic contact with an indium-oxide (In2O3) active layer. These SWCNT-AZO NP hybrid electrodes exhibited a low contact resistance with the solution-processed In2O3 active layer, due to the low work function of the AZO NPs physisorbed on the SWCNTs. The 50 nm-thick SWCNT-AZO NP hybrid films showed a considerably low electrical low electrical resistance of 214.5 Ω/sq, an optical transmittance of 82.1% and a work function of 4.57 eV. By using these materials as the source and drain electrodes, fully solution-processed In2O3 thin film transistors (TFTs) were fabricated and they showed excellent device performance. Furthermore, the fully solution-processed flexible In2O3 TFTs with these SWCNT-AZO NP hybrid electrodes exhibited only a 2.02% decrease in a field effect mobility after 1000 repeated bending stress at a radius of curvature of 3 mm.
[Show abstract][Hide abstract] ABSTRACT: Colorectal cancer (CRC) is one of the leading causes of cancer-related death in the elderly. However, elderly patients with CRC tend to be under-presented in clinical trials and undertreated in clinical practice. Advanced age alone should not be the only criteria to preclude effective therapy in elderly patients with CRC. The best guide about optimal cancer treatment can be provided by comprehensive geriatric assessment. Elderly patients with stage III colon cancer can enjoy the same benefit from adjuvant chemotherapy with 5-fluorouracil/leucovorin or capecitabine as younger patients, without a substantial increase in toxicity. With conflicting results of retrospective studies and a lack of data available from randomized studies, combined modality treatment should be used with great caution in elderly patients with locally advanced rectal cancer. Combination chemotherapy can be considered for older patients with metastatic CRC. For elderly patients who are frail or vulnerable, however, monotherapy or a stop-and-go strategy may be desirable. The use of targeted therapies in older patients with metastatic CRC appears to be promising in view of their better efficacy and toxicity. Treatment should be individualized based on the nature of the disease, the physiologic or functional status, and the patient's preference.
[Show abstract][Hide abstract] ABSTRACT: To investigate the therapeutic effects of mineral oil (MO) and hyaluronic acid (HA) mixture eye drops on the tear film and ocular surface in a mouse model of experimental dry eye (EDE).
Eye drops consisting of 0.1% HA alone or mixed with 0.1%, 0.5%, or 5.0% MO were applied to desiccating stress-induced murine dry eyes. Tear volume, corneal irregularity score, tear film break-up time (TBUT), and corneal fluorescein staining scores were measured at 5 and 10 days after treatment. Ten days after treatment, goblet cells in the conjunctiva were counted after Periodic acid-Schiff staining.
There was no significant difference in the tear volume between desiccating stress-induced groups. The corneal irregularity score was lower in the 0.5% MO group compared with the EDE and HA groups. The 0.5% and 5.0% MO groups showed a significant improvement in TBUT compared with the EDE group. Mice treated with 0.1% and 0.5% MO mixture eye drops showed a significant improvement in fluorescein staining scores compared with the EDE group and the HA group. The conjunctival goblet cell count was higher in the 0.5% MO group compared with the EDE group and HA group.
The MO and HA mixture eye drops had a beneficial effect on the tear films and ocular surface of murine dry eye. The application of 0.5% MO and 0.1% HA mixture eye drops could improve corneal irregularity, the corneal fluorescein staining score, and conjunctival goblet cell count compared with 0.1% HA eye drops in the treatment of EDE.
Korean Journal of Ophthalmology 04/2015; 29(2):131-7. DOI:10.3341/kjo.2015.29.2.131
[Show abstract][Hide abstract] ABSTRACT: A 35-year-old woman received open thyroidectomy for a thyroid nodule that was confirmed as papillary carcinoma. Whole-body I scintigraphy during thyroid ablation demonstrated high uptake in the thyroid bed and multiple focal hot spots in the thorax. SPECT/CT localized the hot spots to the right chest wall and axilla, as well as to the left chest wall. The surgeon recognized these sites to concur with the transaxillary tract used during endoscopic thyroidectomy for nodular hyperplasia 8 years previously. Thus, this case illustrates how thyroidal tissue fragments seeded during endoscopic thyroidectomy can be mistaken for thyroid cancer metastasis on I scintigraphy.
Clinical Nuclear Medicine 03/2015; 40(3):260-262. DOI:10.1097/RLU.0000000000000623 · 3.93 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We introduced a single-wall carbon nanotube (SWCNT)-Al bilayer as electrodes for the high-performance solution processable thin film transistor (TFT). The contact resistance was systematically lowered by inserting an Al layer between the SWCNTs and the indium-oxide (In2O3). The performance of the device was considerably enhanced by adopting the SWCNT-Al bilayer electrodes, thanks to the enlargement of the electrodes contact area and to the formation of an Ohmic contact between the electrodes and the semiconductor. The TFT using the SWCNT-Al bilayer electrodes show a threshold voltage of 0.45 V, a mobility of 4.50 cm2/V∙s and an Ion/Ioff of 6.86 × 105.
[Show abstract][Hide abstract] ABSTRACT: When nonlinear behaviors of soil are important in a soil–structure interaction system, radiation of energy into the infinity of the soil as well as the nonlinearity must be considered rigorously. In this study, perfectly matched discrete layers (PMDLs) are employed to represent the radiation of energy rigorously. A time-domain formulation for a soil–structure interaction is given using the layers. To represent a layered half-space effectively and accurately, a method to determine PMDL parameters for the half-space is proposed. It is demonstrated that the proposed PMDL system can be applied successfully to problems of nonlinear soil–structure interaction.
[Show abstract][Hide abstract] ABSTRACT: We report the rare case of an adult who was diagnosed with recurrent multisystem Langerhans cell histiocytosis (LCH) involving the pituitary stalk and lung who present with central diabetes insipidus and was successfully treated with systemic steroids and chemotherapy. A 49-year-old man visited our hospital due to symptoms of polydipsia and polyuria that started 1 month prior. Two years prior to presentation, he underwent excision of right 6th and 7th rib lesions for the osteolytic lesion and chest pain, which were later confirmed to be LCH on pathology. After admission, the water deprivation test was done and the result indicated that he had central diabetes insipidus. Sella magnetic resonance imaging showed a mass on the pituitary stalk with loss of normal bright spot at the posterior lobe of the pituitary. Multiple patchy infiltrations were detected in both lung fields by computed tomography (CT). He was diagnosed with recurrent LCH and was subsequently treated with inhaled desmopressin, systemic steroids, vinblastine, and mercaptopurine. The pituitary mass disappeared after two months and both lungs were clear on chest CT after 11 months. Although clinical remission in multisystem LCH in adults is reportedly rare, our case of adult-onset multisystem LCH was treated successfully with systemic chemotherapy using prednisolone, vinblastine, and 6-mercaptopurine, which was well tolerated.
[Show abstract][Hide abstract] ABSTRACT: The purpose of the present study was to evaluate factors that affect the occurrence of osteolysis through clinical and radiological comparison between a patient group in which osteolysis occurred after total knee arthroplasty (TKA) and a patient group in which osteolysis did not occur after TKA.
[Show abstract][Hide abstract] ABSTRACT: Aims and background:
This study was conducted to investigate the clinicopathological features and long-term outcomes of patients with skin cancer arising from burn scar (SCBS).
Patients and methods:
We retrospectively reviewed the medical records of patients diagnosed with SCBS between January 2000 and May 2012. A total of 44 patients were enrolled in this study.
The median latent period between burn injury and development of SCBS was 32 years (range, 8-78 years). The most frequent sites of SCBS were the lower limbs (68.2%) followed by the upper limbs (15.9%) and trunk (11.4%). Most patients (95.4%) had squamous cell carcinoma. Of 34 patients with localized disease at the time of diagnosis, 33 patients are alive with no evidence of recurrence. Of 10 patients with regional lymph node metastasis (referred to as locally advanced disease), 4 died of disease progression and 5 are alive with metastatic disease in the lymph nodes, bone or lung. Patients with localized disease survived longer than patients with locally advanced disease ( P = 0.000). In patients with locally advanced disease, the median overall survival time was 16 months (95% CI, 2.88-29.4 months).
While localized SCBS is a potentially curable disease, locally advanced SCBS has a poor prognosis in spite of aggressive treatment. These results suggest that early recognition and aggressive treatment are essential to improve the outcomes of SCBS.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this retrospective study is to investigate the effect of posterior tibial slope (PTS) on clinical results in total knee replacement arthroplasty (TKA).
We analyzed 801 knees in 768 patients who underwent TKA using a cruciate-retaining prosthesis for osteoarthritis from July 2003 to July 2009. PTS was measured on simple X-ray films and patients were divided into 5 groups, according to the change in PTS that was calculated by subtracting the preoperative from the postoperative PTS: group 1, >3°; group 2, 3° to 1°; group 3, 1° to -1°; group 4, -1° to -3°; and group 5, <-3°. We analyzed the correlations between the change in PTS and clinical results, such as Knee Society knee score, Knee Society functional score, Feller patella score, Kujala score, visual analog scale score, range of motion, and complications.
There was no statistically significant intergroup difference; however, Feller patella score and Kujala score were significantly different in groups 2 and 3. There were no complications, such as progressive loosening of implants, fractures of polyethylene inserts and wears.
Clinically meaningful improvement was observed in all patients after TKA. Groups 2 and 3 (3° to -1°) showed significant improvement compared to the other groups.
[Show abstract][Hide abstract] ABSTRACT: The fabrication of fully transparent thin-film transistor (TFT) arrays composed of metal oxides and SWCNTs was performed on a glass substrate through simple all-solution-processed, vacuum-free routes followed by thermal annealing treatments at 350 °C which is the lowest processing temperature reported to date. We adopted fluorine-doped indium tin oxide (ITO:F), stacked zirconium oxide/aluminium oxide/zirconium oxide (ZAZ), indium zinc oxide (IZO), and single-walled carbon nanotubes (SWCNTs) for gate electrodes, gate insulators, channel layers, and source/drain electrodes, respectively, which enabled the fabrication of TFT with desired-performance at a sufficiently low annealing temperature of 350 °C that is compatible with polymer substrates. The TFT fabricated with a back-gated SWCNT/IZO/ZAZ/ITO:F structure was highly transparent with a transmittance of 76.5% in the visible range and exhibited a mobility of 0.45 cm2 V−1 s−1 and an on/off current ratio of 106, which are comparable to those of hydrogenated amorphous silicon TFTs. These results suggest that all-solution-processed TFTs have the potential for lost-cost, fully transparent, flexible device applications.
[Show abstract][Hide abstract] ABSTRACT: Objective:
To evaluate retrospectively whether symptomatic acromioclavicular joints can be differentiated from asymptomatic acromioclavicular joints on 3-T MR imaging.
This study included 146 patients who underwent physical examination of acromioclavicular joints and 3-T MR imaging of the shoulder. Among them, 67 patients showing positive results on physical examination were assigned to the symptomatic group, whereas 79 showing negative results were assigned to the asymptomatic group. The following MR findings were compared between the symptomatic and asymptomatic groups: presence of osteophytes, articular surface irregularity, subchondral cysts, acromioclavicular joint fluid, subacromial fluid, subacromial bony spurs, joint capsular distension, bone edema, intraarticular enhancement, periarticular enhancement, superior and inferior joint capsular distension degree, and joint capsular thickness. The patients were subsequently divided into groups based on age (younger, older) and the method of MR arthrography (direct MR arthrography, indirect MR arthrography), and all the MR findings in each subgroup were reanalyzed. The meaningful cutoff value of each significant continuous variable was calculated using receiver operating characteristic analysis.
The degree of superior capsular distension was the only significant MR finding of symptomatic acromioclavicular joints and its meaningful cutoff value was 2.1mm. After subgroup analyses, this variable was significant in the older age group and indirect MR arthrography group.
On 3-T MR imaging, the degree of superior joint capsular distension might be a predictable MR finding in the diagnosis of symptomatic acromioclavicular joints.
European journal of radiology 12/2012; 82(4). DOI:10.1016/j.ejrad.2012.10.027 · 2.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Tensile tests of an individual ZnS nanowire with a cubic structure were performed with a nano-manipulator inside a scanning electron microscope (SEM). To perform the tensile test of ZnS nanowires, a mechanical testing system was installed in the SEM. A nano-manipulator was set up in the SEM, and a cantilever force sensor was mounted on the nano-manipulator. The force sensor could be controlled with the nano-manipulator. The ZnS nanowires were dispersed on the transmission electron microscope (TEM) grid; then, the ends of the ZnS nanowires were welded to the TEM grid and the tip of force sensor by exposing them to the E-beam of the SEM. The tensile tests of the ZnS nanowires were performed by controlling the nano-manipulator in the SEM. The load response during the tensile tests was obtained with a force sensor. The strain-stress curve was obtained from the tensile load-displacement curve after the tensile test. The tensile strengths for nanowires 1, 2, and 3 were 364.7 ± 5.2, 146.2 ± 5.2, and 234.4 ± 5.2 MPa, respectively, and the elastic moduli for nanowires 1, 2, and 3 were 39 ± 5.2, 33.4 ± 5.2, and 37.4 ± 5.2 GPa, respectively.
Journal- Korean Physical Society 08/2012; 61(3). DOI:10.3938/jkps.61.402 · 0.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Ethylenediaminetetraacetic acid-dependent pseudothrombocytopenia (EDTA-PTCP) is an in vitro phenomenon of EDTA-induced platelet aggregation at room temperature. This phenomenon consists of platelet clumping due to anti-platelet antibodies in blood anticoagulated with EDTA. It has been reported in patients with various diseases, including sepsis, multiple myeloma, acute myocardial infarction and breast cancer. Since unrecognized EDTA-PTCP may lead to inappropriate treatment, it should always be considered as a possible cause in patients with low platelet counts. This study identified a case of transient EDTA-PTCP in a patient with neuroendocrine carcinoma of the stomach. In the present study, a 50-year-old male presented with epigastric pain and a weight loss of 15 kg. The patient presented with EDTA-PTCP and was diagnosed with neuroendocrine carcinoma of the stomach. Following systemic chemotherapy, the tumor showed a marked regression and the EDTA-PTCP disappeared. The mechanism by which this occurred is not clear but an association of EDTA-PTCP with neuroendocrine carcinoma is strongly suggested.
[Show abstract][Hide abstract] ABSTRACT: The diagnosis of pheochromocytoma depends on the documentation of catecholamine overproduction. The use of urinary fractionated metanephrines has recently become common for the diagnosis of pheochromocytoma. In order to avoid false positive and false negative results, optimal cut-off levels are necessary; however, there have been few published reports on whether different cut-off levels are needed to diagnose pheochromocytoma according to sex. We reviewed the medical records of 815 subjects (including 103 pheochromocytoma patients) whose of 24-h urinary fractionated metanephrine was measured using high-performance liquid chromatography methods and adrenal imaging at Samsung Medical Center. Receiver operating characteristic (ROC) curves were used to determine cut-off values according to sex. The upper limit values of fractionated metanephrine in healthy volunteers and the control group were significantly higher in male subjects compared with females. When we applied cut-off values according to sex, the diagnostic efficacies (defining a positive test as either metanephrine or normetanephrine levels above the cut-off value) were a sensitivity of 96% in male subjects and 98.1% in female subjects and a specificity of 88.6% in male subjects and 94.1% in female subjects. However, when we applied cut-off values without considering sex, the specificity decreased from 88.6% to 77.8% in male subjects. In this study, urinary fractionated metanephrines had a high level of sensitivity and specificity for the diagnosis of pheochromocytoma. However, diagnostic cut-off values were higher in male subjects than in female subjects. Therefore, different cut-off values may be needed according to sex to diagnose pheochromocytoma in Koreans.
[Show abstract][Hide abstract] ABSTRACT: The structure of thin-film transistors (TFTs) based on amorphous In–Ga–Zn–O (a-IGZO) was modified by spin coating a suspension of In2O3 nanoparticles on a SiO2/p++ Si layered wafer surface prior to the deposition of IGZO layer by room-temperature sputtering. The number of particles per unit area (surface density) of the In2O3 nanoparticles could be controlled by applying multiple spin coatings of the nanoparticle suspension. During the deposition of IGZO, the In2O3 nanoparticles initially located on the substrate surface migrated to the top of the IGZO layer indicating that they were not embedded within the IGZO layer, but they supplied In to the IGZO layer to increase the In concentration in the channel layer. As a result, the channel characteristics of the a-IGZO TFT were modulated so that the device showed an enhanced performance as compared with the reference device prepared without the nanoparticle treatment. Such an improved device performance is attributed to the nano-scale changes in the structure of (InO)n ordering assisted by increased In concentration in the amorphous channel layer.
Journal of Physics D Applied Physics 05/2012; 45(20). DOI:10.1088/0022-3727/45/20/205303 · 2.72 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The authors aim was to investigate the effects of using transmission and reflection scanning modes, the film orientation during scanning, and ambient room light on a dosimetry system based on the Gafchromic(TM) EBT2 film model.
For calibration, the films were cut to 3 × 3 cm(2) and irradiated from 20 to 700 cGy at the depth of maximum dose using 6 and 10 MV photon beams in a 10 × 10 cm(2) field size. Absolute dose calibration of the linear accelerator was done according to the TRS398 protocol. An FG65-G ionization chamber was used to monitor the dose while irradiating the films in solid water. The film pieces were scanned with an EPSON Expression 1680 Pro flatbed scanner in transmission and reflection modes. Authors investigated the effect of orientation on films and examined the optical properties of EBT2 film using an ellipsometer and an ultraviolet (UV)/visible spectrometer to explain the dosimetric dependence of the film on orientation during the scanning process. To investigate the effect of ambient room light, films were preirradiated in 6 and 10 MV photon beams with intensity-modulated radiotherapy (IMRT) quality assurance (QA) plans, and then exposed to room light, either directly for 2 days in a workroom or for 2 months in a film box. Gamma index pass criteria of (3%, 3 mm) were used.
The dose response curves based on net optical density (NOD) indicated that the reflection scanning mode can provide a better dose sensitivity than the transmission scanning mode, whereas the standard deviation of the dose is greater in reflection mode than in transmission mode. When the film was rotated 90° from the portrait orientation, the average dose of the EBT2 film decreased by 11.5-19.6% in transmission mode and by 1.5-2.3% in reflection mode. Using an ellipsometer, variation of the refractive index of EBT2 film-the birefringence property-was found to be the largest between 45° (1.72 and 1.71) and 135° (1.8 and 1.77) for 300 and 800 cGy. Absorption spectra of EBT2 films measured with spectrometer were the function of film orientation. The readings in reflection scanning mode were more stable against room light than those in transmission scanning mode, although dose readings increased in both modes after the films were exposed to room light.
The transmission scanning mode exhibited a strong dependence on film orientation during scanning and a change in optical density resulting from room light exposure, so a constant scanning orientation and minimal exposure to light can reduce uncertainty in the measured dose (23 ± 3%). The angular dependence was analyzed using Jones matrices and optical properties of EBT2 film were obtained using an ellipsometer and an UV/visible spectrometer. The reflection scanning mode has relatively good stability with respect to room light and film orientation on a scanner, although the large standard deviation of dose is a disadvantage in measurements of absolute dose. Reflection scanning mode can offer a potential advantage for film dosimetry in radiotherapy, although transmission scanning mode is still recommended for dosimetry as it provides better uncertainty results.
Medical Physics 05/2012; 39(5):2524-35. DOI:10.1118/1.3700731 · 2.64 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To determine the accuracy of a three-dimensional (3D) isotropic T1-weighted fast spin-echo (FSE) magnetic resonance (MR) sequence as compared with a conventional two-dimensional (2D) sequence in the diagnosis of rotator cuff tears and labral lesions.
Institutional review board approval was obtained, and the informed consent requirement was waived. Forty-nine patients who had undergone direct or indirect shoulder MR arthrography with the 2D T1-weighted FSE sequence and the 3D isotropic T1-weighted FSE sequence and subsequent arthroscopy were included. Each MR imaging sequence was independently scored by two readers retrospectively for the presence of full- or partial-thickness tears of the supraspinatus (SST) and infraspinatus (IST) tendons and the subscapularis tendon (SCT) and labral lesions. Diagnostic performance based on each sequence type was compared by using the area under the receiver operating characteristic curve (AUC).
Arthroscopic findings enabled confirmation of the presence of 17 full-thickness SST-IST tears, 18 partial-thickness SST-IST tears, four full-thickness SCT tears, 17 partial-thickness SCT tears, and 17 labral lesions. The AUCs for the readers using the 3D T1-weighted FSE sequence versus those obtained with the 2D sequence were 0.771-0.989 versus 0.837-0.998 for reader A and 0.771-0.989 versus 0.797-0.989 for reader B in the detection of rotator cuff tears and 0.885 versus 0.897 for reader A and 0.895 versus 0.895 for reader B in the detection of labral lesions. The mean AUCs between the 2D and 3D sequences were not significantly different, with the exception of partial-thickness SCT tears for one reader.
The accuracy of 3D isotropic FSE MR arthrography may be comparable with that of conventional 2D MR arthrography in the diagnosis of rotator cuff tears and labral lesions with a shorter imaging time.
[Show abstract][Hide abstract] ABSTRACT: We report a case of a man who developed duodenal bleeding caused by direct hepatocellular carcinoma (HCC) invasion, which was successfully treated with endoscopic ethanol injection. A 57-year-old man with known HCC was admitted for melena and exertional dyspnea. He had been diagnosed with inoperable HCC a year ago. Urgent esophagogastroduodenoscopy (EGD) showed two widely eroded mucosal lesions with irregularly shaped luminal protruding hard mass on the duodenal bulb. Argon plasma coagulation and Epinephrine injection failed to control bleeding. We injected ethanol via endoscopy to control bleeding two times with 14 cc and 15 cc separately without complication. Follow-up EGD catched a large ulcer with necrotic and sclerotic base but no bleeding evidence was present. He was discharged and he did relatively well during the following periods. In conclusion, Endoscopic ethanol injection can be used as a significantly effective and safe therapeutic tool in gastrointestinal tract bleeding caused by HCC invasion.
Gut and liver 01/2012; 6(1):122-5. DOI:10.5009/gnl.2012.6.1.122 · 1.81 Impact Factor