Case of colon perforation due to segmental absence of intestinal musculature accompanied by cancer treated with colonic resection and anastomosis.

BACKGROUND: Segmental absence of intestinal musculature (SAIM) is a partial defect of intestinal muscularis propria without diverticulum. Many reports indicate that the increase in intestinal pressure caused by enemas or endoscopic examinations leads to bowel perforation, but there are few reports involving malignant tumors. Moreover, few reports have had good outcomes after performing one-stage intestinal anastomosis. CASE PRESENTATION: A 60-year-old male came to the office with right-side abdominal pain, and was diagnosed with acute generalized peritonitis caused by ascending colon perforation. Emergency laparotomy was performed, and oval and smooth perforation at the ascending colon was observed, which caused ascites with feces. In addition, there was a tumor on the distal side. The terminal ileum was not dilated, so the cause of the perforation was more likely the SAIM-related thin intestinal wall rather than increased internal intestinal pressure due to obstruction of the tumor. Therefore, a right hemicolectomy with functional end-to-end anastomosis (FEEA) between the ascending colon and ileum was performed, rather than creating a stoma. On pathological examination, the resected bowel segments had a partial defect of intestinal muscularis propria around the perforation, leading to the diagnosis of SAIM. The patient had a favorable postoperative course without anastomotic issues and was discharged safely. CONCLUSIONS: This case implies that initial intestinal anastomosis can be performed without creating a stoma when SAIM is suspected from the shape of the perforation and proximal intestine. This case report suggests surgeons should keep SAIM in mind during operations for colon perforations.

Vasopressin-oxytocin-type signaling is ancient and has a conserved water homeostasis role in euryhaline marine planarians.

Vasopressin/oxytocin (VP/OT)-related peptides are essential for mammalian antidiuresis, sociosexual behavior, and reproduction. However, the evolutionary origin of this peptide system is still uncertain. Here, we identify orthologous genes to those for VP/OT in Platyhelminthes, intertidal planarians that have a simple bilaterian body structure but lack a coelom and body-fluid circulatory system. We report a comprehensive characterization of the neuropeptide derived from this VP/OT-type gene, identifying its functional receptor, and name it the "platytocin" system. Our experiments with these euryhaline planarians, living where environmental salinities fluctuate due to evaporation and rainfall, suggest that platytocin functions as an "antidiuretic hormone" and also organizes diverse actions including reproduction and chemosensory-associated behavior. We propose that bilaterians acquired physiological adaptations to amphibious lives by such regulation of the body fluids. This neuropeptide-secreting system clearly became indispensable for life even without the development of a vascular circulatory system or relevant synapses.

Microwave-assisted photooxidation of sulfoxides.

We demonstrated microwave-assisted photooxidation of sulfoxides to the corresponding sulfones using ethynylbenzene as a photosensitizer. Efficiency of the photooxidation was higher under microwave irradiation than under conventional thermal heating conditions. Under the conditions, ethynylbenzene promoted the oxidation more efficiently than conventional photosensitizers benzophenone, anthracene, and rose bengal. Ethynylbenzene, whose T1 state is extremely resistant to intersystem crossing to the ground state, was suitable to this reaction because spectroscopic and related reported studies suggested that this non-thermal effect was caused by elongating lifetime of the T1 state by microwave. This is the first study in which ethynylbenzene is used as a photosensitizer in a microwave-assisted photoreaction.