Spatiotemporal Neural Activities Involved in the Olfactory Processing of the Land Slug using Fluorescent-Imaging Technique

The brain or central nervous system forms a network composed of so many neurons and their function is based on complex interactions among electric neural activities, intracellular calcium signals, intercellular communications by neurotransmitter, and so on. For multi-point measurement of neural activities, fluorescent-imaging technique using voltage-sensitive dyes or calcium-sensitive dyes can be a powerful technique. This technique has been applied to measure spatiotemporal neural activities involved in the olfactory processing of the land slug Limax. In Limax, the procerebral (PC) lobe, which is the olfactory center located in the lateral part of each cerebral ganglion, spontaneously produces a periodic oscillation of local field potential (LFP) of about 1 Hz, and the phase of the LFP oscillation is advanced at the distal region, resulting in periodic propagating waves of neural activity from the distal to proximal regions. The previous studies showed that odor stimuli change the LFP frequency and the wave propagation speed. In this article, we review the previous studies, as well as our recent studies, on the spatiotemporal neural activities of the land slug Limax using fluorescent-imaging technique

Incidence of Gastric Metaplasia and Helicobacter pylori Infection in Duodenal Bulb – With Specific Reference to Patients With Duodenal Ulcers

We determined the incidence of gastric metaplasia in the duodenal bulb of duodenal ulcer patients and the Helicobacter pylori (H. pylori) infection rate at sites with gastric metaplasia. Biopsy of the duodenal bulb showed the presence of gastric metaplasia in 61 of 86 patients (71%) overall and in 18 of 47 patients (38.3%) who had gastrectomy at an early gastric cancer. The histological diagnosis of H. pylori infection showed good agreement (83.3%) with the result of the rapid urease test, indicating that H. pylori occurs in regions with gastric metaplasia. This finding suggests that H. pylori infects gastric metaplasia in the duodenal bulb, causing mucosal injury, which is then transformed into duodenal ulcers. The exact mechanism by which gastric metaplasia is caused is unknown, but it is believed to occur in the transitional zone in the duodenal mucosa

Study on the Optimal Interval of Monitoring Following Gastric Polyp

The present study was conducted to determine how long hyperplastic polyps (HPs) and fundic gland hyperplastic polyps (FGPs) should be endoscopically followed up. Our findings showed that in the case of FGPs, yearly endoscopy is not required and it is sufficient to repeat X-ray and compare films with those obtained in the previous year. In contrast, yearly follow-up by endoscopy is necessary in the case of HPs

Las Mile Problem of Logistics in Internet Trading

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