Temperature-Dependent Tip-Induced Motion of Ga Adatom on GaAs (110) Surface.

The temperature-dependent tip-induced-motion of a Ga adatom on a GaAs (110) surface is experimentally demonstrated using scanning tunneling microscopy (STM). The surface adsorption energy profile obtained by first-principle electronic structure calculations reveals that the origin of the Ga motion observed at 78 K is attributable to the tip-induced Ga adatom hopping between the most stable potential minima among the three local minima, whereas that observed at 4.2 K is attributable to the tip-induced hopping and sliding motions through the next stable minima as well as the most stable minima. Furthermore, it is shown that a slight progressive modification of the adatom motion observed only at 4.2 K resulting from repeated STM line scans is consistent with the overall picture taking account of the heating of the adatom owing to the tip current.

Guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment.

Guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment have been produced by the Japan Gastroenterological Endoscopy Society in collaboration with the Japan Circulation Society, the Japanese Society of Neurology, the Japan Stroke Society, the Japanese Society on Thrombosis and Hemostasis and the Japan Diabetes Society. Previous guidelines from the Japan Gastroenterological Endoscopy Society have focused primarily on prevention of hemorrhage after gastroenterological endoscopy as a result of continuation ofantithrombotic therapy, without considering the associated risk of thrombosis. The new edition of the guidelines includes discussions of gastroenterological hemorrhage associated with continuation of antithrombotic therapy, as well as thromboembolism associated with withdrawal of antithrombotic therapy.

New developments in diagnosis and non-surgical treatment of chronic pancreatitis.

Chronic pancreatitis is progressive and irreversible, leading to digestive and absorptive disorders by destruction of the exocrine pancreas and to diabetes mellitus by destruction of the endocrine pancreas. When complications such as pancreatolithiasis and pseudocyst occur, elevated pancreatic ductal pressure exacerbates pain and induces other complications, worsening the patient's general condition. Combined treatment with extracorporeal shock-wave lithotripsy and endoscopic lithotripsy is a useful, minimally invasive, first-line treatment approach that can preserve pancreatic exocrine function. Pancreatic duct stenosis elevates intraductal pressure and favor both pancreatolithiasis and pseudocyst formation, making effective treatment vitally important. Endoscopic treatment of benign pancreatic duct stenosis stenting frequently decreases pain in chronic pancreatitis. Importantly, stenosis of the main pancreatic duct increases risk of stone recurrence after treatment of pancreatolithiasis. Recently, good results were reported in treating pancreatic duct stricture with a fully covered self-expandable metallic stent, which shows promise for preventing stone recurrence after lithotripsy in patients with pancreatic stricture. Chronic pancreatitis has many complications including pancreatic carcinoma, pancreatic atrophy, and loss of exocrine and endocrine function, as well as frequent recurrence of stones after treatment of pancreatolithiasis. As early treatment of chronic pancreatitis is essential, the new concept of early chronic pancreatitis, including characteristics findings in endoscopic ultrasonograms, is presented.

Clinical features of eosinophilic esophagitis: ten Japanese cases.

AIM: We studied eosinophilic esophagitis (EE) to clarify the clinical and endoscopic features of a Japanese case series. METHODS: Records of 10 patients diagnosed with EE at our hospital between May 2010 and December 2011 were examined for age, sex, symptoms, allergic disorder, endoscopic findings, and treatment received. Esophageal wall thickness was measured by endoscopic ultrasonography (EUS). RESULTS: Patients were seven males and three females with a mean age of 48 years. Symptoms included dysphagia, heartburn, food impaction, and chest pain. Nine patients had a history of allergic diseases. Increased peripheral eosinophil count was observed in one patient whereas increased immunoglobulin E level was observed in eight patients. Endoscopic findings included longitudinal furrows in all patients, mucosal edema in nine patients, loss of vascular pattern in nine patients, white exudates in six patients, cobblestone-like appearance in five patients, and concentric rings in three patients. EUS revealed thickening of the esophageal wall in one patient. Histopathological examination revealed eosinophilic infiltration (≥15 eosinophils/high-powered field) in the esophageal epithelium of all patients. Treatment was required in six patients. Proton pump inhibitor (PPI) therapy was given as the first-line treatment but was ineffective in four patients and effective in two patients. Steroid therapy was given to three patients unresponsive to PPI therapy and was effective. CONCLUSIONS: EE was common among relatively young men and was associated with allergic diseases. Longitudinal furrows were observed as the most characteristic endoscopic finding. Esophageal wall thickening was not commonly observed by EUS.

[Diagnosis of the depth of gastric cancer invasion by endoscopic ultrasonography].

Endoscopic ultrasonography (EUS) is useful to diagnose the depth of invasion because of obtaining tomographic image of gastric cancer. Stomach layer has a 5-layer structure. Gastric cancer is visualized as low echoic tumor image by EUS. Massive invasion of gastric cancer is viewed as low echoic and clear boundary image. Diffuse invasion is imaged unclear boundary echo and visualized thick layer with remaining layer structure. Invasion depth of gastric cancer by EUS is diagnosed according to level of wall destruction. When depressed type cancer has ulceration in cancer nest, echoic image is modified with fibrous tissue. The diagnostic criteria of depressed type cancer classified into EUS imaging of cancer in consideration for image modified by fibrous tissue accompanied ulceration.

[Guideline of prevention and treatment for NSAIDs induced ulcer].

The guideline for peptic ulcer treatment was reported by Japanese Society of Gastroenterology in 2009. In the guideline, 23 clinical questions were chosen for NSAIDs induced ulcer. Nine questions out of them were related to the prevention, eight were low dose aspirin, three were COX-2 inhibitors and three were the treatment. The recommendations were made for these questions according to evidence-based medicine. In the recommendations, the grade of recommendation, the evidence level of literatures and the applications to Japanese medical insurance were mentioned.

Evidence-based clinical practice guidelines for peptic ulcer disease 2020.

The Japanese Society of Gastroenterology (JSGE) revised the third edition of evidence-based clinical practice guidelines for peptic ulcer disease in 2020 and created an English version. The revised guidelines consist of nine items: epidemiology, hemorrhagic gastric and duodenal ulcers, Helicobacter pylori (H. pylori) eradication therapy, non-eradication therapy, drug-induced ulcers, non-H. pylori, and nonsteroidal anti-inflammatory drug (NSAID) ulcers, remnant gastric ulcers, surgical treatment, and conservative therapy for perforation and stenosis. Therapeutic algorithms for the treatment of peptic ulcers differ based on ulcer complications. In patients with NSAID-induced ulcers, NSAIDs are discontinued and anti-ulcer therapy is administered. If NSAIDs cannot be discontinued, the ulcer is treated with proton pump inhibitors (PPIs). Vonoprazan (VPZ) with antibiotics is recommended as the first-line treatment for H. pylori eradication, and PPIs or VPZ with antibiotics is recommended as a second-line therapy. Patients who do not use NSAIDs and are H. pylori negative are considered to have idiopathic peptic ulcers. Algorithms for the prevention of NSAID- and low-dose aspirin (LDA)-related ulcers are presented in this guideline. These algorithms differ based on the concomitant use of LDA or NSAIDs and ulcer history or hemorrhagic ulcer history. In patients with a history of ulcers receiving NSAID therapy, PPIs with or without celecoxib are recommended and the administration of VPZ is suggested for the prevention of ulcer recurrence. In patients with a history of ulcers receiving LDA therapy, PPIs or VPZ are recommended and the administration of a histamine 2-receptor antagonist is suggested for the prevention of ulcer recurrence.

Endoscopic approach via the minor duodenal papilla.

BACKGROUND/AIMS: We describe procedures for endoscopic approach via the minor papilla in symptomatic patients with pancreas divisum, pancreatic stones, and stricture of the Santorini's duct, and neoplasms of the minor papilla: endoscopic minor papilla sphincterotomy, endoscopic pancreatic stone removal, endoscopic stent placement in Santorini's duct, and resection of minor papilla neoplasms. METHODS: The most important procedural detail was insertion of a guide wire into Santorini's duct via the minor papilla, requiring gentle manipulation of both the cannula and guide wire to avoid subsequent complications such as pancreatitis. RESULTS: Minor papilla sphincterotomy was most effective in the treatment of patients with pancreas divisum and associated with acute recurrent pancreatitis; these patients are the best candidates for endoscopic dorsal duct decompression including minor papilla sphincterotomy and stenting. Endoscopic treatment via the minor duodenal papilla was the only useful method for patients whose lesions could not be approached via the major papilla. It is a safe procedure to relieve pain. Long-term results of dorsal ductal stenting were satisfactory in 76 and 90% of patients (19/25 and 9/10, respectively). CONCLUSION: The high level of endoscopic skills necessary and the small number of patients who need these procedures should limit this approach to select institutions with appropriate endoscopic expertise.

[New guideline for peptic ulcer treatment, attention to low-dose aspirin].

The guideline for peptic ulcer treatment was reported in 2009. In the guideline, eight clinical questions were chosen for peptic ulcers associated with use of low-dose aspirin. Five questions out of them were related to the clinical behavior, and three were the treatment of peptic ulcers in patients taking low-dose aspirin. The statements were made for these questions according to EBM respectively. In the statements, the grade of recommendation, the evidence level of literatures and the application to Japanese medical insurance were mentioned.

Differential diagnosis and treatment of biliary strictures.

Biliary tract strictures present both diagnostic and therapeutic challenges to clinicians. Advances in imaging and endoscopic techniques have improved our ability to differentiate between benign and malignant lesions. Intraductal ultrasonography (IDUS), using an endoscopic approach, has the potential to aid in separating benign and malignant biliary lesions. In a series of 93 patients, a majority of whom had cancer, we found that IDUS had a sensitivity and specificity of 89.7% and 84%, respectively, for diagnosing biliary strictures. However, benign strictures associated with untreated autoimmune pancreatitis and/or the intrapancreatic portion of the distal common bile duct could not be easily distinguished from malignant strictures. Direct visualization of biliary mucosa using a percutaneous transhepatic endoscopic approach also helps separate benign from malignant biliary strictures. Further, the ability to obtain multiple directed biopsies using a percutaneous approach also increases diagnostic accuracy. A final advantage of the percutaneous approach is that once a suitable sized tract has been established, biliary strictures and stents can be placed. IDUS and percutaneous biliary endoscopy are promising new modalities for the diagnosis and treatment of biliary strictures.

Real Space Imaging of Topological Edge States in InAs/GaSb and InAs/InxGa1-xSb Quantum Wells.

Structure dependent differential tunneling conductance, dI/dV, profiles obtained using scanning tunneling microscopy on both (110)-cleaved surfaces and (001)-growth surfaces in InAs/GaSb and InAs/InxGa1-xSb quantum wells (QWs), which are platforms of two-dimensional topological insulator (2D-TI), clearly demonstrated the edge states formed on the 2D-TI surfaces. The results were confirmed by kp-based electronic structure calculations, which demonstrated that the edge states extended to the 10 nm range from cleaved surfaces generated in the appropriately designed InAs/(In)GaSb QW systems.

Importance of nutritional status in recovery from acute cholecystitis: benefit from enteral nutrition supplementation including medium chain triglycerides.

This study was undertaken to clarify the importance of nutritional status in patients with acute cholecystitis, and also evaluate whether they benefited from enteral nutrition supplementation, including medium-chain triglycerides (MCT), during the convalescent stage. Patients with acute cholecystitis admitted to our hospital between April 1994 and March 2002 were classified into a poor nutrition group (n=40; total serum protein<5.0 g/dl) or a fair nutrition group (n=71; >5.0 g/dl). Patients with poor nutrition were significantly more elderly than those with fair nutrition, and had significantly higher serum C-reactive protein (CRP) concentrations. The two groups did not differ significantly with respect to other laboratory data, gender distribution, or medical treatment. We supplemented ordinary meals with enteral nutrition including MCT in 16 patients during the convalescent stage (MCT group). We compared their length of hospital stay and days required to recovery to pre-admission functional status for activities of daily living (ADL) with the same intervals in 16 patients without supplementation (non-MCT group) selected to match for age, gender, and fair or poor nutritional status from among 111 patients. Hospitalizations were significantly longer in the poor nutrition group (43.0+/-2.2 days) than in the fair nutrition group (27.0+/-8.2 days). Significantly more days were required to recover ADL status in the poor nutrition group (12.0+/-7.2 days) than in the fair group (9.4+/-5.2 days). Hospitalizations were significantly shorter in the MCT group (20.1+/-15 days) than in the non-MCT group (35.4+/-12.8 days). Significantly fewer days were required to recover ADL status in the MCT group (10.9+/-7 days) than in the non-MCT group (13.1+/-6.8 days). Administration of enteral nutrition including MCT during convalescence from acute cholecystitis thus appears to promote functional recovery shorten hospital stay.

[Usefulness of contrast-enhanced ultrasonography in the differential diagnosis of polypoid gallbladder lesions].

We investigated the usefulness of contrast-enhanced ultrasonography for differential diagnosis of polypoid gallbladder lesions in 60 patients, consisting of gallbladder carcinoma in 20, adenoma in 2, benign polyp in 29, and adenomyomatosis in 9, comparing contrast enhancement patterns with pathologic findings. We monitored vascular flow for 120 sec, constructing a time intensity curve (TIC) by flash-echo imaging. We compared the number of vessels and vessel diameter determined by contrast enhancement patterns and by pathologic examination. Contrast enhancement patterns were classified as linear, scattered, diffuse, or branched. When diffuse type and branched type were considered as indicative of cancer, accuracy was 84.5%, sensitivity 100%, and specificity 76.9%. In gallbladder carcinoma, the TIC rose from no contrast to early-phase contrast sooner than in other diseases. In adenocarcinoma, high-intensity values persisted at 120 sec. With an intensity of 90 or greater at 120 sec taken as indicating cancer, accuracy was 89.7%, sensitivity 89.5%, and specificity 89.7%; Vessels were significantly more numerous in diffuse type cases than in those with other patterns. Vessel diameter was greatest in the diffuse type and the branched type patterns, both differing significantly from the linear type. Ultrasonographic contrast enhancement patterns show characteristic associations with pathologic findings and serve as valuable adjuncts in the diagnosis of gallbladder diseases.

Protective effect of N,N'-dimethylthiourea against stress-induced gastric mucosal lesions in rats.

In the present study, we examined the protective effect of N,N'-dimethylthiourea (DMTU), a scavenger of hydroxyl radical (·OH), against water-immersion restraint stress (WIRS)-induced gastric mucosal lesions in rats. When male Wistar rats fasted for 24 h were exposed to WIRS for 3 h, gastric mucosal lesions occurred with increases in the levels of gastric mucosal myeloperoxidase (MPO), an index of tissue neutrophil infiltration, pro-inflammatory cytokines (tumor necrosis factor alpha and interleukin 1beta), lipid peroxide (LPO), and nitrite/nitrate (NOx), an index of nitric oxide synthesis, and decreases in the levels of gastric mucosal nonprotein SH and vitamin C and gastric adherent mucus. DMTU (1, 2.5, or 5 mmol/kg) administered orally at 0.5 h before the onset of WIRS reduced the severity of gastric mucosal lesions with attenuation of the changes in the levels of gastric mucosal MPO, pro-inflammatory cytokines, LPO, NOx, nonprotein SH, and vitamin C and gastric adherent mucus found at 3 h after the onset of WIRS in a dose-dependent manner. Serum levels of corticosterone and glucose, which are indices of stress responses, increased in rats exposed to WIRS for 3 h, but DMTU pre-administered at any dose had no effect on these increases. These results indicate that DMTU protects against WIRS-induced gastric mucosal lesions in rats by exerting its antioxidant action including ·OH scavenging and its anti-inflammatory action without affecting the stress response.

Impact of lipoprotein lipase gene polymorphisms on ulcerative colitis.

AIM: To examine the influence of lipoprotein lipase (LPL) gene polymorphism in ulcerative colitis (UC) patients. METHODS: Peripheral blood was obtained from 131 patients with UC and 106 healthy controls for DNA extraction. We determined LPL gene polymorphisms affecting the enzyme at Ser447stop, as well as Hind III and Pvu II polymorphisms using PCR techniques. PCR products were characterized by PCR-RFLP and direct sequencing. Polymorphisms were examined for association with clinical features in UC patients. Genotype frequencies for LPL polymorphisms were also compared between UC patients and controls. RESULTS: In patients with onset at age 20 years or younger, C/G and G/G genotypes for Ser447stop polymorphism were more prevalent than C/C genotype (OR = 3.13, 95% CI = 0.95-10.33). Patients with H(+/-) or H(-/-) genotype for Hind III polymorphism also were more numerous than those with H(+/+) genotype (OR = 2.51, 95% CI = 0.85-7.45). In the group with H(+/+) genotype for Hind III polymorphism, more patients had serum triglyceride concentrations over 150 mg/dL than patients with H(+/-) or H(-/-) genotype (P < 0.01, OR = 6.46, 95% CI = 1.39-30.12). Hypertriglycemia was also more prevalent in patients with P(+/+) genotypes for Pvu II polymorphism (P < 0.05, OR = 3.0, 95% CI = 1.06-8.50). Genotype frequency for LPL polymorphism did not differ significantly between UC patients and controls. CONCLUSION: Ser447stop and Hind III LPL polymorphisms may influence age of onset of UC, while Hind III and Pvu II polymorphisms influence serum triglyceride in UC patients.

Evidence-based clinical practice guidelines for peptic ulcer disease 2015.

The Japanese Society of Gastroenterology (JSGE) revised the evidence-based clinical practice guidelines for peptic ulcer disease in 2014 and has created an English version. The revised guidelines consist of seven items: bleeding gastric and duodenal ulcers, Helicobacter pylori (H. pylori) eradication therapy, non-eradication therapy, drug-induced ulcer, non-H. pylori, non-nonsteroidal anti-inflammatory drug (NSAID) ulcer, surgical treatment, and conservative therapy for perforation and stenosis. Ninety clinical questions (CQs) were developed, and a literature search was performed for the CQs using the Medline, Cochrane, and Igaku Chuo Zasshi databases between 1983 and June 2012. The guideline was developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Therapy is initially provided for ulcer complications. Perforation or stenosis is treated with surgery or conservatively. Ulcer bleeding is first treated by endoscopic hemostasis. If it fails, surgery or interventional radiology is chosen. Second, medical therapy is provided. In cases of NSAID-related ulcers, use of NSAIDs is stopped, and anti-ulcer therapy is provided. If NSAID use must continue, the ulcer is treated with a proton pump inhibitor (PPI) or prostaglandin analog. In cases with no NSAID use, H. pylori-positive patients receive eradication and anti-ulcer therapy. If first-line eradication therapy fails, second-line therapy is given. In cases of non-H. pylori, non-NSAID ulcers or H. pylori-positive patients with no indication for eradication therapy, non-eradication therapy is provided. The first choice is PPI therapy, and the second choice is histamine 2-receptor antagonist therapy. After initial therapy, maintenance therapy is provided to prevent ulcer relapse.

Inflammatory myofibroblastic tumor (inflammatory fibrosarcoma) of the pancreas: a case report.

Inflammatory myofibroblastic tumors (inflammatory fibrosarcomas) of the pancreas are extremely rare. We report a 29-year-old woman who underwent pancreatoduodenectomy for a 6-cm tumor of the pancreas head causing obstructive jaundice. Tumor involvement was local, without apparent metastasis. The tumor was composed of proliferating fibroblastic/or myofibroblast-like spindle cells and aggregates of chronic inflammatory cells in a fibromyxoid matrix. Immunohistochemical examination demonstrated reactivity only to vimentin. This tumor has often been found in the peritoneal cavity, the retroperitoneum, or the pelvic cavity, but only very rarely in the pancreas.