Analysis of IGZO crystalline structure and its stability by first-principles calculations

In-Ga-Zn oxide (IGZO), an oxide semiconductor, has been actively researched as a semiconductor material having features different from those of silicon in recent years [1]. IGZO is used as a transistor material in backplanes of commercially available displays. Transistors including crystalline IGZO have high stability and thus are suitable for mass production [2]. Our previous studies revealed that the selected area diffraction pattern of an IGZO film formed at room temperature by sputtering is a halo pattern, whereas diffraction spots are observed in the diffraction pattern obtained by nanobeam electron diffraction with a probe diameter of 1 nm [3,4]. These results suggest that the IGZO film has rather nanometer-sized crystalline structures than a completely amorphous structure. We named this film “nano-crystalline IGZO (nc-IGZO) film.” Other researchers have reported that the nc-IGZO film has a crystalline-cluster composite structure, according to the analysis results obtained by grazing-incidence X-ray diffraction, anomalous X-ray scattering, and reverse-Monte-Carlo simulation [5]. In this study, an IGZO structure having a minute crystalline region, which was considered to exist in nc-IGZO as a local structure, was created by first-principles calculations and its stability was analyzed. The IGZO model having a crystalline region used in this study was obtained by a melt-quench method in the following manner. Note that the initial structure had a hexagonal-prism crystalline region at the center and an amorphous region (random atomic arrangement) around the crystalline region. The composition ratio was In:Ga:Zn:O = 1:1:1:4 and the density was 6.1 g/cm3. First, for structural relaxation with the crystalline region maintained, the amorphous region was fused in quantum molecular dynamics simulation (3500 K, 6 ps) while the atomic arrangement of the crystalline region was fixed, and the structure was cooled to 500 K at a rate of 500 K/ps and held at 300 K for 5 ps. Finally, the entire structure including the crystalline region was optimized towards the target structure (Fig. 1). An amorphous model was also created for reference. The amorphous model was obtained by quantum molecular dynamics simulation of the entire structure under similar temperature conditions without fixing the atomic arrangement of the crystalline region, followed by structural optimization. The comparison between the two models showed that the total energy of the IGZO model having a crystalline region was lower than that of the amorphous model (not having a crystalline region). This suggests that the crystalline region contributes to structure stabilization. Please click Additional Files below to see the full abstract

Adenomyoepithelioma of the Breast A with an Immunohistochemical Study

Adenomyoepithelioma is a rare primary tumor of the breast in women. It is characterized by a bicellular pattern consisting of both ductal and myoepithelial elements. We report here an additional case of adenomyoepithelioma in a 57-year-old woman. The aspiration cytology revealed atypical cell clusters, and the simple mastectomy was performed under the diagnosis of ductal carcinoma. Macroscopically, the tumor presented as a well-defined mass. Histologically, the tumor demonstrated the characteristic bicellular growth pattern consisting of ducts and a periductal proliferation of mainly polygonal neoplastic cells. Immunohistochemically, epithelial cells lining the glandular structures were strongly positive for cytokeratin and epithelial membrane antigen (EMA). Polygonal myoepithelial cells gave negative reactions with cytokeratin and EMA. Most polygonal myoepithelial cells were positive for ﾎｱ-smooth muscle actin (SMA) and S-100 protein. Our case was a representative example of a typical adenomyoepithelioma, but the cytological diagnosis needs a deep attention to avoid overdiagnosis

Sinus Fungus Ball in the Japanese Population: Clinical and Imaging Characteristics of 104 Cases

Sinus fungus ball is defined as noninvasive chronic fungal rhinosinusitis occurring in immunocompetent patients with regional characteristics. The clinical and imaging characteristics of paranasal sinus fungus ball were retrospectively investigated in 104 Japanese patients. All patients underwent endoscopic sinus surgery. Preoperative computed tomography (CT), magnetic resonance (MR) imaging, age, sex, chief complaint, causative fungus, and clinical outcome were analyzed. Patients were aged from 25 to 79 years (mean 58.8 years). Female predominance was noted (58.7%). Most common symptoms were nasal discharge and facial pain. CT showed high density area in 82.0% of the cases (82/100), whereas T2-weighted MR imaging showed low intensity area in 100% of the cases (32/32). Histological examination showed that most causative agents were Aspergillus species (94.2% (98/104)). Culture test was positive for 16.7% (11/66). Recurrence was found in 3.2% (3/94). Older age and female predominance were consistent with previous reports. MR imaging is recommended to confirm the diagnosis

Osteopontin as a Mediator of NKT Cell Function in T Cell-Mediated Liver Diseases

AbstractBoth osteopontin (OPN) and natural killer T (NKT) cells play a role in the development of immunological disorders. We examined a functional link between OPN and NKT cells. Concanavalin A (Con A)-induced hepatitis is a well-characterized murine model of T cell-mediated liver diseases. Here, we show that NKT cells secrete OPN, which augments NKT cell activation and triggers neutrophil infiltration and activation. Thus, OPN- and NKT cell-deficient mice were refractory to Con A-induced hepatitis. In addition, a neutralizing antibody specific for a cryptic epitope of OPN, exposed by thrombin cleavage, ameliorated hepatitis. These findings identify NKT cell-derived OPN as a novel target for the treatment of inflammatory liver diseases

Blockade of interaction of α9 integrin with its ligands hinders the formation of granulation in cutaneous wound healing

The wound healing is a complex process consisting of inflammatory reaction, proliferation of mesenchymal cells, and formation and contraction of granulation tissue. The integrin receptors play crucial roles in this process. Recently, α9 integrin has also been detected on keratinocytes within wound sites. However, its functional significance at various wound healing processes was not fully elucidated. To address the role of α9 integrin in wound healing process, we made a full-thickness skin excisional wound and treated mice with anti-α9 integrin antibody. It has been shown that wound healing process was divided into three distinct phases; first, re-epithelialization phase, second phase of granulation tissue formation, and followed by final phase of contraction of granulation tissue. We found that contraction of granulation tissue was not impaired by blocking the interaction of α9 integrin with its ligands, indicating that α9 integrin is not involved in myofibroblast differentiation. Of note, formation of granulation tissue as characterized by dense vimentin and CD31 positive area was impaired. The hindrance of granulation tissue formation is due to the inhibition of adhesion and migration of α9 integrin positive dermal fibroblasts. In conclusion, α9 integrin is involved in the formation of granulation tissue via regulating migration and adhesion of dermal fibroblasts in the full-thickness skin excisional wound model

Utility of Early Post-treatment Single-Photon Emission Computed Tomography Imaging to Predict Outcome in Stroke Patients Treated with Intravenous Tissue Plasminogen Activator

It is important to predict the outcome of tissue plasminogen activator (tPA)-treated patients early after the treatment for considering the post-tPA treatment option. We assessed cerebral blood flow (CBF) of tPA-treated patients with single-photon emission computed tomography (SPECT) 1 hour after tPA infusion to predict the patient outcome. Technetium-99m-hexamethylpropyleneamine oxime SPECT was performed in 35 consecutive tPA-treated patients. Asymmetry index, a contralateral-to-ipsilateral ratio of CBF, was calculated to analyze CBF quantitatively. Hypoperfusion or hyperperfusion was defined as a decrease of 25% or more or a increase of 25% or more in asymmetry index, respectively. Of all 35 patients, 23 had only hypoperfusion, 8 had both hypoperfusion and hyperperfusion, 2 had only hyperperfusion, and 2 had no perfusion abnormality. When evaluating the association between hypoperfusion and outcome, hypoperfusion volumes were significantly correlated with the modified Rankin Scale at 3 months (r = .634, P < .001). Hyperperfusion was observed in 10 patients (28.6%) and they showed a marked National Institutes of Health Stroke Scale score improvement in the first 24-hour period, which were significantly greater than those of 25 patients without hyperperfusion (P = .033). Eight patients (22.9%) with intracerebral hemorrhage (ICH) were all asymptomatic. Most ICHs were located in hypoperfusion areas, and no ICH was related to hyperperfusion. The results of the present study demonstrated that hypoperfusion volume was associated with poor outcome, whereas the presence of hyperperfusion seemed to be predictive of symptom improvement but not of development of ICH. Taken together, early post-treatment SPECT imaging seems to be a useful biomarker of outcome in tPA-treated patients

Comparison between high and low potency statins in the incidence of open-angle glaucoma: A retrospective cohort study in Japanese working-age population.

Some findings on the association between glaucoma and statins in the Asian population have been reported. We conducted a retrospective cohort study using health insurance claims data maintained by the JMDC Inc., which comprises data on about three million individuals representing 2.4% of the Japanese population. The association between the potency of statins and open-angle glaucoma in Japanese working-age population was examined using a commercially available health insurance claims and enrollment database. We identified 117,036 patients with a prescription of statins between January 1, 2005 and March 31, 2014; 59,535 patients were selected as new statin users. Of these, 49,671 (83%) patients without glaucoma who were prescribed statins for the first time were part of the primary analysis. New users of statin were defined as those with a prescription of statin at the beginning of the study, but without a prescription six months earlier. The cohort comprised 29,435 (59%) and 20,236 (41%) patients with a prescription of high-potency statin (atorvastatin and rosuvastatin) and low-potency statin (pravastatin, fluvastatin, pitavastatin, and simvastatin), respectively. Using Cox proportional hazards regression analysis, hazard ratios (HRs) were estimated for glaucoma adjusted for baseline characteristics. Although some baseline characteristics were not similar between the high-potency and low-potency statin groups, the standardized difference for all covariates was less than 0.1. No associations were found between high-potency statin use and glaucoma (adjusted HR = 1.08; 95% confidence interval, 0.93-1.24) in the primary analyses, using the risk for glaucoma in the low-potency statin group as reference. The risk of glaucoma with individual statin use was not significantly different from that with pravastatin. No significant association was found between high-potency statins and the increased risk of glaucoma in Japanese working-age population. Further studies are needed to examine the association between statins and glaucoma in the elderly population