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Laparoscopic proximal gastrectomy (LPG) is an attractive option for the treatment of early gastric cancer in the upper third of the stomach. No optimal method of reconstruction after LPG has been established because of problems associated with postoperative reflux. Gastric tube reconstruction, a type of esophagogastrostomy, is a simple procedure, but it is associated with a high frequency of reflux esophagitis (RE). We investigated the relationship between RE and gastric emptying, along with nutritional parameters.We compared gastric emptying in patients who had undergone curative LPG with gastric tube reconstruction for gastric cancer with that of patients after total gastrectomy (TG), distal gastrectomy (DG) and of healthy volunteers and patients after DG. The LPG group was divided into an RE LPG-RE (+) group and a non-reflux esophagitis (non-RE) an LPG-RE (-) group, and we compared gastric emptying and indices of nutrition, such as body weight and laboratory findings, between those among LPG-RE (+), LPG-RE (-), and TG groups.The time lag between ingestion and peak 13 CO 2 expiration (T lag) in the healthy volunteer group was significantly shorter in the LPG group longer than those in the healthy volunteer LPG group and TG group. The T lag was significantly shorter in the RE LPG-RE (+) group than in the non-RE LPG-RE (-) group. The percentage change in body weight percentage in the non-RE LPG-RE (-) group was significantly larger than that in the RE LPG-RE (+) group at 12 months after surgery. Both the serum albumin and hemoglobin levels in the non-RE LPG-RE (-) tended to be preserved compared with those in the RE LPG-RE (+) group and TG group.Gastric emptying was accelerated after LPG, and was associated with RE. Our data suggest that RE could be associated with body weight loss after LPG.

Endocytoscopy (EC) facilitates real-time histological diagnosis of esophageal lesions in vivo. We developed a deep-learning artificial intelligence (AI) system for analysis of EC images and compared its diagnostic ability with that of an expert pathologist and nonexpert endoscopists. Our new AI was based on a vision transformer model (DeiT) and trained using 7983 EC images of the esophagus (2368 malignant and 5615 nonmalignant). The AI evaluated 114 randomly arranged EC pictures (33 ESCC and 81 nonmalignant lesions) from 38 consecutive cases. An expert pathologist and two nonexpert endoscopists also analyzed the same image set according to the modified type classification (adding four EC features of nonmalignant lesions to our previous classification). The area under the curve calculated from the receiver-operating characteristic curve for the AI analysis was 0.92. In per-image analysis, the overall accuracy of the AI, pathologist, and two endoscopists was 91.2%, 91.2%, 85.9%, and 83.3%, respectively. The kappa value between the pathologist and the AI, and between the two endoscopists and the AI showed moderate concordance; that between the pathologist and the two endoscopists showed poor concordance. In per-patient analysis, the overall accuracy of the AI, pathologist, and two endoscopists was 94.7%, 92.1%, 86.8%, and 89.5%, respectively. The modified type classification aided high overall diagnostic accuracy by the pathologist and nonexpert endoscopists. The diagnostic ability of the AI was equal or superior to that of the experienced pathologist. AI is expected to support endoscopists in diagnosing esophageal lesions based on EC images.

Seeded growth of 2-inch-diameter GaN crystals via low-pressure (∼100 MPa) acidic ammonothermal method is demonstrated. Nearly bowing- and mosaic-free GaN crystals exhibiting full-width at half-maximum values for the 0002 X-ray rocking curves below 20 arcsec were achieved on high lattice coherency c-plane SCAATTM seeds with gross dislocation densities in the order of 104 cm−2. The photoluminescence spectra of the grown crystals exhibited a predominant near-band-edge emission at 295 K, of which intensity was one order of magnitude higher than the characteristic deep-state emission bands. A nearly bowing-free 60 mm × 60 mm c-plane GaN crystal was eventually obtained.