Oxidation of Anatase TiO2(001) Surface Using Supersonic Seeded Oxygen Molecular Beam.

We investigated the oxidation of oxygen vacancies at the surface of anatase TiO2(001) using a supersonic seeded molecular beam (SSMB) of oxygen. The oxygen vacancies at the top surface and subsurface could be eliminated by the supply of oxygen using an SSMB. Oxygen vacancies are present on the surface of anatase TiO2(001) when it is untreated before transfer to a vacuum chamber. These vacancies, which are stable in the as-grown condition, could also be effectively eliminated by using the oxygen SSMB.

Hydrothermal Synthesis and Crystal Structure of a (Ba0.54K0.46)4Bi4O12 Double-Perovskite Superconductor with Onset of the Transition Tc ∼ 30 K.

A new superconducting double perovskite was successfully synthesized by a low-temperature hydrothermal reaction at 240 °C. The crystal structure refinement of this double perovskite was done by single-crystal X-ray diffraction, and it had a cubic unit cell of a = 8.5207(2) Å with space group Im3̅m (No. 229). This superconducting double-perovskite chemical composition was estimated by electron probe microanalysis and was similar to the refined data. The superconducting transition temperature of the double perovskite was ∼30 K; the electrical resistivity began to fall at ∼25 K, and zero resistivity occurred below 7 K. Moreover, temperature-dependent resistivity under various magnetic fields and isothermal magnetization measurements ensured the nature of a type II superconductor for the sample. Finally, the metallic nature of the material was investigated by a first-principles study.

Prediction of colorectal tumor grade and invasion depth through narrow-band imaging scoring.

AIM: To determine the usefulness of assigning narrow-band imaging (NBI) scores for predicting tumor grade and invasion depth in colorectal tumors. METHODS: A total of 161 colorectal lesions were analyzed from 138 patients who underwent endoscopic or surgical resection after conventional colonoscopy and magnifying endoscopy with NBI. The relationships between the surface and vascular patterns of the lesions, as visualized with NBI, and the tumor grade and depth of submucosa (SM) invasion were determined histopathologically. Scores were assigned to distinct features of the surface microstructures of tubular and papillary-type lesions. Using a multivariate analysis, a model was developed for predicting the tumor grade and depth of invasion based on NBI-finding scores. RESULTS: NBI findings that correlated with a high tumor grade were associated with the "regular/irregular" (P < 0.0001) surface patterns and the "avascular area" pattern (P = 0.0600). The vascular patterns of "disrupted vessels" (P = 0.0714) and "thick vessels" (P = 0.0133) but none of the surface patterns were associated with a depth of invasion of ≥ 1000 µm. In our model, a total NBI-finding score ≥ 1 was indicative of a high tumor grade (sensitivity: 0.97; specificity: 0.24), and a total NBI-finding score ≥ 9 (sensitivity: 0.56; specificity: 1.0) was predictive of a SM invasion depth ≥ 1000 µm. Scores less than these cutoff values signified adenomas and a SM invasion depth < 1000 µm, respectively. Associations were also noted between selected NBI findings and tumor tissue architecture and histopathology. CONCLUSION: Our multivariate statistical model for predicting tumor grades and invasion depths from NBI-finding scores may help standardize the diagnosis of colorectal lesions and inform therapeutic strategies.

Emergence of Wrinkles during the Curing of Coatings.

Wrinkles often emerge on a paint layer when a second coat of paint is applied on an already-coated substrate. Wrinkle formation occurs when the first layer absorbs organic solvent from the second layer. We set up experiments to mimic the double-coating process, focusing on the interaction between a paint layer and an organic solvent. In the experiments, we investigated the characteristic wavelengths of the wrinkles and the time of wrinkle emergence. We employed a simple model to explain the wrinkle emergence and performed numerical simulations. The linear stability analysis of the model provides a relation between the wavelengths and the characteristic timescale that agrees reasonably well with our experimental data as well as numerical results. Our results indicate that compression of the layer due to swelling and delamination are both important factors in the formation of wrinkles.

In vivo dose response and in vitro mechanistic analysis of enhanced immunoglobulin A production by Lactobacillus plantarum AYA.

Secretory immunoglobulin A (IgA) mediates the mucosal immune system, which provides the first line of defense against inhaled and ingested pathogenic bacteria and viruses. Lactobacillus plantarum AYA increases the IgA level of Peyer's patch (PP) cells, but the recommended amount of consumption and the mechanism of action remains unclear. Better understanding of these is essential to development of L. plantarum AYA for use in functional foods. Therefore, we investigated the dose-response effect (in vivo) and mechanism (in vitro) of IgA enhancement induced by L. plantarum AYA. In the small intestine of the mice fed a diet containing 0.03% or 0.3% of L. plantarum AYA powder for 4 weeks, the IgA levels were significantly increased. Thus, it is suggested that the recommended amount of consumption of L. plantarum AYA is about 0.72 mg per day. In addition, the bacterial cell wall fraction significantly enhanced the IgA production level of murine PP cells in the in vitro assay. The ability of whole cells and the cell wall fraction to enhance IgA levels was significantly inhibited by an anti-Toll-like receptor-2 (TLR-2) antibody, which suggests that the cell wall fraction of L. plantarum AYA increases the IgA level via TLR-2. These findings indicate that L. plantarum AYA is a potential functional food source that maintains mucosal immunity.

Diagnosis of early gastric cancer using narrow band imaging and acetic acid.

AIM: To determine whether the endoscopic findings of depressed-type early gastric cancers (EGCs) could precisely predict the histological type. METHODS: Ninety depressed-type EGCs in 72 patients were macroscopically and histologically identified. We evaluated the microvascular (MV) and mucosal surface (MS) patterns of depressed-type EGCs using magnifying endoscopy (ME) with narrow-band imaging (NBI) (NBI-ME) and ME enhanced by 1.5% acetic acid, respectively. First, depressed-type EGCs were classified according to MV pattern by NBI-ME. Subsequently, EGCs unclassified by MV pattern were classified according to MS pattern by enhanced ME (EME) images obtained from the same angle. RESULTS: We classified the depressed-type EGCs into the following 2 MV patterns using NBI-ME: a fine-network pattern that indicated differentiated adenocarcinoma (25/25, 100%) and a corkscrew pattern that likely indicated undifferentiated adenocarcinoma (18/23, 78.3%). However, 42 of the 90 (46.7%) lesions could not be classified into MV patterns by NBI-ME. These unclassified lesions were then evaluated for MS patterns using EME, which classified 33 (81.0%) lesions as MS patterns, diagnosed as differentiated adenocarcinoma. As a result, 76 of the 90 (84.4%) lesions were matched with histological diagnoses using a combination of NBI-ME and EME. CONCLUSION: A combination of NBI-ME and EME was useful in predicting the histological type of depressed-type EGC.

Clinical characteristics and management of gastric tube cancer with endoscopic submucosal dissection.

AIM: To identify the characteristics of gastric tube cancer (GTC) and the complications associated with endoscopic submucosal dissection (ESD) for GTC. METHODS: Between 2007 and 2012, 11 individuals with early gastric cancer in the reconstructed gastric tube after esophagectomy who underwent ESD in this hospital were studied. The characteristics of GTC were identified, and the complications of ESD for GTC were analyzed at three phases: preoperative, intraoperative, and postoperative. RESULTS: A total of 11 consecutive patients with 11 GTCs were selected for this study. All cases underwent en bloc resections by ESD. The median procedure time was 142 min. The average GTC diameter was 26.1 mm, and the average size of the resected lesions was 45.5 mm. The histopathological diagnosis in all cases was a differentiated adenocarcinoma. In the preoperative phase, anastomotic strictures (5/11, 45%) and food residues (4/11, 36.4%) in the gastric tube were the main complications. In the intraoperative phase, bleeding was observed in 5 cases (45%). The postoperative complications observed were delayed bleeding in 2 cases (18.2%) and stenosis in one case (9.1%). The case with stenosis was successfully treated using endoscopic balloon dilatation. CONCLUSION: Minor complications were frequently observed. However, all GTCs underwent en bloc resection with ESD without any serious complications. ESD is considered a useful treatment for GTC.

Usefulness of magnifying endoscopy with narrow-band imaging for diagnosis of depressed gastric lesions.

The usefulness of magnifying endoscopy with narrow-band imaging (ME-NBI) for the diagnosis of early gastric cancer is well known, however, there are no evaluation criteria. The aim of this study was to devise and evaluate a novel diagnostic algorithm for ME-NBI in depressed early gastric cancer. Between August, 2007 and May, 2011, 90 patients with a total of 110 depressed gastric lesions were enrolled in the study. A diagnostic algorithm was devised based on ME-NBI microvascular findings: microvascular irregularity and abnormal microvascular patterns (fine network, corkscrew and unclassified patterns). The diagnostic efficiency of the algorithm for gastric cancer and histological grade was assessed by measuring its mean sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. Furthermore, inter- and intra-observer variation were measured. In the differential diagnosis of gastric cancer from non-cancerous lesions, the mean sensitivity, specificity, PPV, NPV, and accuracy of the diagnostic algorithm were 86.7, 48.0, 94.4, 26.7, and 83.2%, respectively. Furthermore, in the differential diagnosis of undifferentiated adenocarcinoma from differentiated adenocarcinoma, the mean sensitivity, specificity, PPV, NPV, and accuracy of the diagnostic algorithm were 61.6, 86.3, 69.0, 84.8, and 79.1%, respectively. For the ME-NBI final diagnosis using this algorithm, the mean κ values for inter- and intra-observer agreement were 0.50 and 0.77, respectively. In conclusion, the diagnostic algorithm based on ME-NBI microvascular findings was convenient and had high diagnostic accuracy, reliability and reproducibility in the differential diagnosis of depressed gastric lesions.

A case of mediastinal pancreatic pseudocyst successfully treated with somatostatin analogue.

A 57-year-old man with a 3-year history of chronic pancreatitis was admitted to our hospital with upper abdominal pain. Based on examination findings, the patient was diagnosed as having pseudocysts in the pancreatic body and the mediastinum that were associated with acute aggravation of chronic pancreatitis. Because of the patient refused an operation, he was submitted to conservative management including intramuscular injection with somatostatin analogue of 100 microg/day. On the 14th day of the treatment, pleural effusion and pseudocyst in the pancreatic head were additionally diagnosed based on the findings of computed tomography, magnetic resonance imaging and other examinations, and the dose of somatostatin analogue was increased to 200 microg/day. As a result, on the 28th day of the treatment, pancreatitis was inactivated, and the pseudocysts in the mediastinum and the pancreas disappeared. The patient has been followed up for 15 months, and there has been no recurrence.