Effect of Vonoprazan on Delayed Bleeding after Endoscopic Submucosal Dissection for Gastric Neoplasia among Antithrombotic Drug Users: A Single-Center, Single-Arm Prospective Observational Case Control Study

Antithrombotic therapy is a major risk factor for delayed bleeding after endoscopic submucosal dissection (ESD) for gastric neoplasia. A potassium-competitive acid blocker, vonoprazan, is expected to prevent delayed bleeding better than conventional proton pomp inhibitors (PPIs), but the evidence is controversial. We sought to clarify the efficacy of vonoprazan for prevention of delayed bleeding after gastric ESD in patients under antithrombotic therapy. We prospectively registered 50 patients who underwent gastric ESD while receiving antithrombotic therapy and vonoprazan in our institution between October 2017 and September 2018. The incidence of delayed bleeding was compared with that in a historical control group of 116 patients treated with conventional PPI. We also evaluated risk factors associated with delayed bleeding. Delayed bleeding was observed in 8 of 50 patients (16.0%), which was not dissimilar from the incidence in the historical control group (12.1%) (p=0.49). In the univariate analysis, age (> 70 years) (p=0.034), multiple antithrombotic drug use (p 200 min) (p=0.038) and tumor size (> 40 mm) (p<0.01) were associated with delayed bleeding after gastric ESD, but vonoprazan was not (p=0.49). Vonoprazan may not be more effective than conventional PPIs in preventing delayed bleeding after gastric ESD in patients receiving antithrombotic therapy

Linked Color Imaging and Blue Laser Imaging for Upper Gastrointestinal Screening

White light imaging (WLI) may not reveal early upper gastrointestinal cancers. Linked color imaging (LCI) produces bright images in the distant view and is performed for the same screening indications as WLI. LCI and blue laser imaging (BLI) provide excellent visibility of gastric cancers in high color contrast with respect to the surrounding tissue. The characteristic purple and green color of metaplasias on LCI and BLI, respectively, serve to increase the contrast while visualizing gastric cancers regardless of a history of Helicobacter pylori eradication. LCI facilitates color-based recognition of early gastric cancers of all morphological types, including flat lesions or those in an H. pylori-negative normal background mucosa as well as the diagnosis of inflamed mucosae including erosions. LCI reveals changes in mucosal color before the appearance of morphological changes in various gastric lesions. BLI is superior to LCI in the detection of early esophageal cancers and abnormal findings of microstructure and microvasculature in close-up views of upper gastrointestinal cancers. Excellent images can also be obtained with transnasal endoscopy. Using a combination of these modalities allows one to obtain images useful for establishing a diagnosis. It is important to observe esophageal cancers (brown) using BLI and gastric cancers (orange) surrounded by intestinal metaplasia (purple) and duodenal cancers (orange) by LCI

Optimum Driving of Magnetostrictive Amorphous Wire Micro-Motor

Characteristics of a magnetostrictive vibration micro-motor were investigated in relationto a supporting position of a magnetostrictive amorphous wire for optimization of themotor. It was found that a vibration of the wire resembled a vibration mode of both endsfree and a maximum rotational speed was obtained by supporting the nodes of vibration

17 beta-HSD Type 12-Like Is Responsible for MaturationInducing Hormone Synthesis During Oocyte Maturation in Masu Salmon

The maturation-inducing hormone 17(alpha), 20(beta)-dihydroxy-4-pregnen-3-one (DHP) was first identified in the amago salmon. Although carbonyl reductase-like 20 beta-hydroxysteroid dehydrogenase (CR/20b-HSD) was reported to convert 17 alpha-hydroxyprogesterone (17OHP) to DHP in rainbow trout, we previously found that CR/20 beta-HSD messenger RNA (mRNA) was not upregulated in stimulated granulosa cells from masu salmon, which suggested that DHP is synthesized by a different enzyme. Accordingly, the current study aimed to identify the specific 20 beta-hydroxysteroid dehydrogenase (20 beta-HSD) responsible for DHP production by granulosa cells during final oocyte maturation in masu salmon. RNA sequencing was performed on granulosa layers that were isolated from ovarian follicles at 1 month before ovulation and incubated with or without forskolin, which was used to mimic luteinizing hormone, and similar to 12 million reads were obtained, which yielded 71,062 contigs of > 100 bp. tBlastx analysis identified 1 contig (#f103496)as similar to 17 beta-hydroxysteroid dehydrogenase type 12 (hsd17 beta 12); however, because the full-length #f103496 sequence was different from hsd17 beta 12, it was termed hsd17 beta 12-like (hsd17 beta 12l). We found that mammalian cells transfected with full-length hsd171 beta 2l exhibited considerable 20b-HSD activity, as indicated by efficient conversion of exogenous 17OHP to DHP. In addition, we found that hsd17 beta 12l mRNA levels were consistently low in follicles during vitellogenic growth; however, the levels increased significantly during final oocytematuration. The levels of hsd17 beta 12lmRNA were also considerably increased in granulosa layers in which 20 beta-HSD activity was induced by salmon pituitary extract. Therefore, we suggest that hsd17 beta 12l, not CR/20 beta-HSD, is the 20 beta-HSD responsible for DHP production by granulosa cells in masu salmon during final oocytematuration

Oriented Nanocrystal Mosaic in Monodispersed CaCO₃ Microspheres with Functional Organic Molecules

Monodispersed microspheres of vaterite CaCO₃ with a diameter adjusted to the range of 1–10 μm were produced through an amorphous intermediate with polystyrene sulfate. Whereas the microspheres were composed of nanocrystals with a diameter of ca. 20 nm covered with the organic polymer, the crystallographic direction of the entire sphere was evaluated to be macroscopically uniform from its single-crystalline features on polarization anisotropy and morphological evolution into a hexagonal shape with an additional growth process. A particular mosaic with a radially grown backbone structure consisting of oriented nanocrystals was suggested to exist in the microspheres from the electron diffraction patterns. The rigid mosaic framework was covered with a flexible organic component. Thus, various functional organic molecules including hydrophilic and hydrophobic dyes were successfully introduced into the microspheres due to the amphiphilic nature of the organic phase