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Renovation of the aged steel railway structures is of vital importance due to their long service life after completion. A strengthening method for aged steel railway bridges by using rubber-latex mortar, glass fiber–reinforced polymer plates, lightweight rapid hardening concrete, and reinforcing bars was introduced in this article. To confirm the real effect of the present strengthening method, field tests were performed on two aged steel railway bridges that have been in service for 87 and 61 years, respectively. Stress variations on the mid-span section of the railway bridge due to the running trains were measured in the field test, and the stress reduction effects as well as the load redistribution effects of the present strengthening method were also confirmed. Three-dimensional finite-element models were built, and the numerical results were in good agreement with the field test results. Besides, structural vibration and noise levels of both strengthened and un-strengthened railway bridges were measu...

Japanese highway bridge design codes have been modified a lot since the Hyogoken-Nanbu Earthquake in 1995, but only used for designing new bridges. The aged steel piers constructed with old design code should be strengthened appropriately to adopt with current design code. With the purpose of improving the seismic performance of existing steel piers, a preventive seismic retrofit method by using GFRP plate, rapid hardening concrete, rubber-latex mortar, and reinforcement is proposed in this paper. The static loading tests on the steel piers before and after strengthening were performed to confirm the effects of the present strengthening method. Moreover, three- dimensional FE models were built to make a comparison study between the strengthened and the original steel piers. Load versus deflection relationship and sectional strain distribution on the piers were measured and compared between original piers and strengthened piers. Both experimental and numerical results indicate that the present strengthening method can greatly enhance the stiffness and reduce the stress levels of steel pier, resulting in the extension service life and improvement of the seismic performance of aged steel piers.

Structural repairing or maintenance technique has been a hot issue in recent years due to the increasing aging problems of old railway bridges. A strengthening method for welded joints in old steel railway bridges by integrating the rapid hardening concrete, rubber-latex mortar, and reinforcing bars is introduced in this paper. The purpose of the present study is to investigate the mechanical performance of the strengthened connection joints in old steel railway bridges. Depending on the locations of the concrete and possible loading conditions, the joint needs to sustain both negative and positive bending moment, therefore, two experimental plans were employed. The static loading tests on the steel joints before and after strengthening were performed to confirm the effects of the present strengthening method. Moreover, three-dimensional FE models were built to make a comparison study between the strengthened and original steel joints. Load versus deflection relationship and strain development process on the web of the joints were measured and compared between the original joints and the strengthened joints. Both experimental and numerical results indicate that the present strengthening method can greatly enhance the stiffness and reduce the stress levels of steel joints, resulting in the extension service life of aged steel railway bridges.

Little is known about acute upper gastrointestinal (GI) complications associated with gemcitabine-concurrent proton radiotherapy (GPT) for inoperable pancreatic cancer. We investigated acute GI complications following GPT in patients with inoperable pancreatic cancer using small-bowel endoscopy. This prospective single center observational study was conducted at the Hyogo Ion Beam Medical Center from January 2010 to January 2012. Ninety-one patients who had clinically and medically inoperable pancreatic cancer treated by GPT were analyzed. Endoscopic examinations were performed before and after GPT to clarify the incidence rates of radiation-induced ulcers, GI hemorrhage, and GI perforation associated with GPT. Post-treatment endoscopic examinations revealed that 45 (49.4 %) patients had radiation-induced ulcers in the stomach and duodenum. Of those, many ulcerative lesions were found in the lower stomach (51 %) and horizontal part of the duodenum (39 %), regardless of the primary tumor site in the pancreas. Neither GI hemorrhage, nor perforation, was found in post-treatment endoscopy examinations. Approximately half of the patients treated with GPT for inoperable pancreatic cancer exhibited radiation-induced ulcers in the stomach and duodenum.

Fujikazu OHKUBO Taiheiyo Material Co. Koutou,Tokyo,Japan Fujikazu-Okubo@ taiheiyo-m.co.jpWeiwei LIN Associate Professor Waseda Univ.Shinjuku,Tokyo,Japanlinweiwei@aoni.waseda.jpShinyaSATAKE Taiheiyo Material Co. Sakura,Chiba, Japan Shinya-Satake@taiheiyo-m.co.jpTeruhiko YODAProfessor Waseda Univ.Shinjuku,Tokyo,Japanyoda1914@waseda.jpThis research offers a new composite revamping method for railway bridges by assuming composite remodelling process of existing steel bridges having no specific fissure damages or serious corrosions and effectively making use of relatively new materials to it. Effects of noise reduction and improved stiffness were further confirmed through hammer impact tests (vibration measurement tests) and loading tests in order to prove the efficacy of the composite remodelling.

Aspiration pneumonia is an emerging problem in patients receiving gastrostomy feeding. This study is designed to clarify the therapeutic effects of mosapride citrate and lansoprazole for prevention of aspiration pneumonia in patients receiving gastrostomy feeding.The study subjects were 119 patients with dysphasia who required gastrostomy feeding. They were randomly assigned to the control (without medication), lansoprazole (15 mg, 1/day), and mosapride (5 mg, 3/day) groups. The number of days with fever (≥37.8 °C), vomiting, and antibiotics administration, as well as the occurrence of pneumonia were investigated during the 6-month observation period.The incidence of pneumonia during the observation period was significantly lower in the mosapride group as compared to the control (7/38 vs. 16/40, p = 0.038) and lansoprazole (vs. 20/41, p = 0.005) groups. The mosapride group also showed a significant decrease in days with fever and antibiotics administration as compared to the other groups. Multivariate analysis revealed that the presence of hiatal hernia was a significant risk factor and administration of mosapride was a significant preventive factor for pneumonia.Mosapride has a preventive effect on occurrence of pneumonia in patients receiving gastrostomy feeding.

The PTEN tumor suppressor localizes predominantly to the cytoplasm, where it negatively regulates the phosphatidylinositol 3-kinase-AKT signaling pathway; however, the biological significance of nuclear PTEN in gastric carcinoma (GC) remains unknown. In this study, transduction of recombinant PTEN into GC-derived TMK-1 cells promoted PTEN nuclear localization with increased mRNA levels of CDX2 and intestinal claudins (CLDN3 and CLDN4), whereas the G129E phosphatase 'dead' mutant had no effect. In GC tissue samples, tumors with nuclear PTEN expression frequently demonstrated the intestinal-type claudin phenotype. Our results suggested that nuclear localization of PTEN is important for determining intestinal differentiation of GCs.

According to the expression of gastric (claudin-18) and intestinal claudins (claudin-3 and claudin-4), the authors have previously proposed a new phenotypic classification of gastric carcinoma (GC): the gastric (G-CLDN), intestinal (I-CLDN) and unclassified claudin (U-CLDN) phenotypes. The aim of the present study was to examine the role of Cdx2, the caudal-related transcription factor, on the regulation of intestinal claudins expression in vitro and in vivo. It was confirmed on immunohistochemistry that non-neoplastic gastric mucosa with intestinal metaplasia (IM) expressed Cdx2 with increased levels of intestinal claudin expression. In addition, Cdx2 expression was detected in 28 (30%) of 94 GC at the invasive front. Interestingly, Cdx2 expression had a significant association with the I-CLDN phenotype (P < 0.001), which was almost identical to the established gastric and intestinal mucin-based GC classification. Furthermore, the transfection of a recombinant human CDX2-expressing vector into TMK-1 (Cdx2-negative) GC cells specifically elevated the expression of claudin-3 and claudin-4 at the mRNA (CLDN3, 3.9-fold; CLDN4, 2.8-fold) and protein levels (claudin-3, 8.6-fold; claudin-4, 9.8-fold), whereas no induction of the other claudins was detected. These findings suggest that Cdx2 plays an important role in the regulation of intestinal claudin expression not only in gastric mucosa with IM but also GC.

The essential contribution of the epithelial-mesenchymal transition (EMT) to carcinoma progression is the loss of their epithelial characters, gain of mesenchymal marker expression, acquisition of migration, invasive activity and capability to pass through the basement membrane. In this study, we aimed to clarify the role of EMT regulator Snail, a zinc finger transcription factor, in human oesophageal squamous cell carcinoma (OESCC). Most OESCC cell lines expressed epithelial cell-cell adhesion molecules such as E-cadherin and claudin-1 and -7; however, TE-8 (Snail-positive) cells expressed mesenchymal marker vimentin but not E-cadherin and claudins. Transduction of ectopic Snail in TE-15 (Snail-negative) cells diminished expression of these epithelial adhesion molecules with promotion of cell migration, invasion and proliferation as well as the shift from cobblestone-like appearance to spindle morphology. In OESCC tissue samples, immunohistochemical analyses revealed that the nuclear Snail expression at the invasive front was correlated with the high levels of vimentin expression (p = 0.0061), which was conversely associated with reduced expressions of E-cadherin (p = 0.023), claudin-1 (p = 0.0246) and claudin-7 (p = 0.0161). Interestingly, elevated Snail expression at the invasive front of the OESCC was associated with higher incidence of lymphatic (p = 0.0143) and venous vessels invasion (p = 0.0029), lymph node metastasis (p = 0.0074) and clinicopathological tumour stage (p = 0.0057). According to the expressions of epithelial and mesenchymal markers, the tumours were subclassified into three groups, the epithelial-type OESCC and the complete or incomplete EMT-type OESCCs. Snail-positive tumours were frequently categorized into the complete- or incomplete-type EMT phenotypes. Our present results suggest the significance of Snail-associated EMT in the progression of OESCC. Snail-induced EMT at the invasive front of the OESCC can be a novel marker for the prediction of metastasis.

There are various types of snares for endoscopic mucosal resection (EMR). Some endoscopists may choose the snare according to their feeling, but we supposed that there were some physical reasons behind each choice. In this paper, we raise the questions, ‘What is the best snare chosen for EMR?’, and ‘Why do we have to do it?’. From the theory of dynamics, we thought that the most important element was vertical force, which we could add against mucosa through the snare. First, we made two situations; one was keeping horizontal faced position of loop of snare (we defined it as HPW; horizontal faced position weight), and the other was rising up position of it (we defined it as RPW). We inspected these forces for the representative and different seven snares, and calculated the ‘Effective Range’, which was a RPW minus a HPW in average. The results demonstrated that both the spiral snare and the smaller ‘Snare Master’ showed higher than other snares in HPW, RPW, and the Effective Range. Based on our study, we judged them as the most adequate snares for EMR in physics and logicality.

All-ceramic ball bearings with silicone nitride balls and silicone nitride rings were tested and the vibration characteristics were compared with those of hybrid ceramic ball bearings and conventional steel ball bearings. The vibration measurement results showed that the overall vibratory velocity levels of the all-ceramic ball bearings are influenced by rotational velocities, and do not change with axial loads. Under a given axial load and rotational velocity, the overall vibratory velocity level of the all-ceramic ball bearing is the lowest, and the hybrid ball bearing the highest. The frequencies of main peaks in the measured vibration spectra of the all-ceramic ball bearing are higher than the frequencies of the corresponding main peaks for the hybrid ceramic ball bearing and the steel ball bearing. To explain the main peaks, modal analysis was done and the relationship between peak and natural vibration was analyzed. The results of the analyses showed that the main peaks are caused by: (1) the mass-type natural vibration of the outer ring in the vertical direction, (2) the bending natural vibration of the outer ring in the radial direction, (3) the moment of inertia-type natural vibration of the outer ring in the angular direction, (4) the mass-type natural vibration of the outer ring in the axial direction, and (5) the bending natural vibration of the outer ring in the axial direction. We also discuss the generating mechanism of the vibration and present the calculation method of the vibration spectra. As a result, it is clear that the vibration spectra of the all-ceramic ball bearing are determined by the amplitude of the waviness of the raceways and ball surface, the mobility, and the non-linear spring constant associated with the contact between the raceways and balls.

This research offers a new composite-revamping method for railway bridges. It assumes that the composite remodeling process of existing steel bridges has no specific fissure damages or serious corrosion, and effectively makes use of relatively new materials. The effects of noise reduction and improved stiffness were further confirmed through hammer-impact tests (vibration and noise measurement tests) in order to prove the efficacy of the composite remodeling.

This research offers a new composite revamping method for railway bridges by assuming composite remodelling process of existing steel bridges having no specific fissure damages or serious corrosions and effectively making use of relatively new materials to it. Effects of noise reduction and improved stiffness were further confirmed through hammer impact tests (vibration measurement tests) and loading tests in order to prove the efficacy of the composite remodelling.

We report a case of gastric serrated hyperplastic lesion with minute adenocarcinoma. A 65-year-old Japanese man underwent endoscopic submucosal dissection to the superficially elevated-type (0-IIa) lesion located at the lesser curvature of the gastric angle. Histological observation revealed hyperplastic change of foveolar epithelium with serrated glandular structure as well as a minute tubular adenocarcinoma component. Immunohistochemically, the lesion demonstrated gastrointestinal, predominantly gastric, phenotype (MUC5AC++, MUC6+, MUC2+, CD10-). Positive p53 immunoreactivity was detected in the carcinoma component of the lesion with a point mutation (G877T; R209I) of the gene and microsatellite instability of the BAT-RII locus; however, immunoreactivity of the mismatch repair gene product hMLH1 was well preserved in the cancer as well as in the hyperplastic lesion. The hyperplastic lesion with serrated glandular pattern would be a precancerous lesion of adenocarcinoma of the stomach.

Although gastric cancer remains the second most common malignancy worldwide, its incidence and mortality has fallen dramatically during the last 50 years. Correa (1992) reported that the consequences of early gastric cancer (EGC) are comparatively good. Endoscopic treatment of EGC is being widely applied and carries with it some improvement for their prognosis; therefore, it was reported by Nagano et al. (2005) that many patients have been able to avoid open–surgery and maintain better quality of life. For these reasons, endoscopic resection of EGC is now the standard therapy in Japan and has been increasingly accepted and regularly used in other countries. Recently, Ono et al. (2001) reported that an innovational technique for endoscopic submucosal dissection (ESD) has been developed for en bloc resection. Toyonaga et al. (2006) reported that ESD has also made it possible to give an accurate diagnosis by pathological examination of EGC. On the other hand, it was reported by Hamanaka and Gotoda (2005) that endoscopic treatment excises only gastric carcinoma tissues, which implies that patients are still at risk of developing metachronous cancer from the remnant mucosa of the stomach. Therefore, molecular diagnosis is required for the screening of patients expected to have metachronous gastric carcinoma. It was proposed by Kinzler and Vogelstein (1996) that recent molecular biological studies have uncovered that there are at least two distinct genetic pathways for gastrointestinal carcinogenesis: the suppressor pathway and the mutator pathway. The suppressor pathway is caused by inactivation of tumor suppressor genes (e.g., APC and p53) and activation of oncogenes (e.g., K–ras) and the tumors demonstrate chromosomal instability; whereas in the mutator pathway, dysfunctions of the DNA mismatch repair (MMR) system is the profound abnormality that leads to the accumulation of nucleotide insertion/deletion mutation at the short repeat sequences in the genome, called microsatellites. The repeating unit comprising a microsatellite can be as short as one or two nucleotides. These regions of the genome tend to be polymorphic or variable among different 12 Early Gastric Cancer: Prediction of Metachronous Recurrence Using Endoscopic Submucosal Dissection (Methodology)

Endoscopic submucosal dissection (ESD) is useful in en bloc curative resection and enables patients with early gastric carcinoma (GC) to have a better quality of life. But metachronous recurrence of GC at other sites in the stomach has become a major issue after initial ESD. The purpose of the present paper was to examine gastric (claudin-18) and intestinal claudin (claudin-3 and claudin-4) expression in early GC on immunohistochemistry to clarify the association with clinicopathology, mucin phenotypes, microsatellite instability (MSI) status and the incidence of synchronous and metachronous gastric epithelial neoplasias after initial ESD. According to intestinal claudin expression, a total of 73 early GC were divided into two groups: intestinal claudin-positive (I-CLDN(+)) phenotype (n = 52; 71%); and intestinal claudin-negative (I-CLDN(-)) phenotype (n = 21; 29%). Although no significant association was found with clinicopathology and the MSI status, the I-CLDN(+) early GC correlated with the mucin phenotypes and had a significantly higher incidence of synchronous and metachronous multiple GC and gastric adenomas (P = 0.049). These results indicate that early GC demonstrating I-CLDN(+) phenotype have a high risk of synchronous and metachronous secondary gastric epithelial neoplasias.