Hangeshashinto-Associated Mesenteric Phlebosclerosis and Highly Atypical Adenoma Requiring Laparoscopic Right Hemicolectomy

Mesenteric phlebosclerosis is a rare ischemic colonic disorder caused by impaired venous drainage. Its prevalence is higher in East Asia, where herbal medicine is widely used. Treatment remains controversial. A 76-year-old woman who had taken Hangeshashinto, an herbal medicine, for 11 years was admitted for endoscopic treatment of high-grade dysplasia in the ascending colon. She had diarrhea and mesenteric phlebosclerosis diagnosed by abdominal computed tomography at age 71. At age 75, small polyps were detected in the ascending colon. A subsequent study revealed an increase in polyp size to 15 mm. Endoscopic mucosal resection failed to remove the lesion. A biopsy showed high-grade dysplasia with possible colon cancer risk. Conservative therapy did not improve mesenteric phlebosclerosis-related diarrhea; therefore, a laparoscopic right hemicolectomy was performed. Intraoperatively, the cecum was adherent to the abdominal wall and the right ovary. The specimen showed high-grade dysplasia in the mucosa and severe submucosal fibrosis. No metastasis was observed. This case shows the link between mesenteric phlebosclerosis and high-grade dysplasia in the ascending colon. Endoscopic mucosal resection was unsuccessful in removing the tumor. Endoscopic submucosal dissection was an alternative, but its safety in mesenteric phlebosclerosis-affected colonic segments remains uncertain. A laparoscopic right hemicolectomy was performed

Passivation of Copper: Benzotriazole Films on Cu (111)

Benzotriazole (BTAH) has been used as a copper corrosion inhibitor since the 1950s. However, the molecular level detail of how adsorption and surface passivation occur remains a matter of debate. BTAH adsorption on a Cu(111) single crystal has been investigated from medium coverage to multilayer using scanning tunneling microscopy (STM), temperature-programmed desorption (TPD), high resolution electron energy loss (HREEL) spectroscopy and supporting density functional theory (DFT) calculations. Both physisorbed and chemisorbed phases are observed. One extended and highly ordered self-assembled metal−organic phase is seen at saturation coverage and above. A metastable phase is also observed. Complete desorption occurs at ca. 600 K. Those structures are critically discussed in the light of some of the various adsorption models reported in the literature and an alternative adsorption model is proposed. These results allow a further understanding of the interaction between benzotriazole and copper and, in turn, may help understanding the mechanism for protection of copper and copper alloys from corrosion, substantially contributing to a long-standing debate

Chemisorbed and physisorbed structures for 1,10-phenanthroline and dipyrido[3,2-a : 2 ',3 '-c]phenazine on au(111)

Scanning tunneling microscopy (STM) images of 1,10-phenanthroline (PHEN) and dipyrido[3,2-a:2&lsquo;,3&lsquo;-c]phenazine (DPPZ) on Au(111) are recorded using both in situ and ex situ techniques. The images of PHEN depict regimes of physisorption and chemisorption, whereas DPPZ is only physisorbed. All physisorbed structures are not pitted and fluctuate dynamically, involving aligned (4 &times; 4) surface domains with short-range (ca. 20 molecules) order for PHEN but unaligned chains with medium-range (ca. 100 molecules) order for DPPZ. In contrast, the chemisorbed PHEN monolayers remain stable for days, are associated with surface pitting, and form a (4 &times; &radic;13)R46&deg; lattice with long-range order. The density of pitted atoms on large gold terraces is shown to match the density of chemisorbed molecules, suggesting that gold adatoms link PHEN to the surface. For PHEN, chemisorbed and physisorbed adsorbate structures are optimized using plane-wave density-functional theory (DFT) calculations for the surface structure. Realistic binding energies are then obtained adding dispersive corrections determined using complete-active-space self-consistent field calculations using second-order perturbation theory (CASPT2) applied to cluster-interaction models. A fine balance between the large adsorbate&minus;adsorbate dispersive forces, adsorbate&minus;surface dispersive forces, gold ligation energy, and surface mining energy is shown to dictate the observed phenomena, leading to high surface mobility and substrate/surface lattice incommensurability. Increasing the magnitude of the dispersive forces through use of DPPZ, rather than PHEN, to disturb this balance produced physisorbed monolayers without pits and/or surface registration but with much longer-range order. Analogies are drawn with similar but poorly understood processes involved in the binding of thiols to Au(111).<br /