Single-cell gene variation analysis method for single gland.

Single-cell analysis of heterogeneity has become the cutting-edge technology for profound understandings of relationships between cell populations. At present, common methods used in single cellular genomic research are mainly microfluidic technologies (Fluidigm) or based on microwells, both requiring a uniform size of cells at the entrance. However, the size of cells in specific tissues can vary from type to type. To address this issue, we need to establish a method to identify genomic features of individual cells of different sizes. In this paper, we developed a robust method in the analysis of single cellular genomic mutations among gastric tissues. Briefly, the single gastric gland was isolated from the whole tissue, and further enzymatically digested into single cells of various sizes by trypsin. These single cells were then spread on the polyethylene naphthalene slides and selected by the laser microdissection method. Whole genome amplification (WGA) and capillary electrophoresis were performed subsequently to detect single cell microsatellite. This method enabled us to detect the existence of microsatellite instability (MSI) of each single cell within the intestinal metaplasia, and to carry out a flexible and fine analysis of single cells with different sizes in tissues and glands. This reliable and practical method is well performed in both low and high-throughput genome analysis when combined with cell labeling methods, thus providing a novel and highly flexible way to study tissue heterogeneity on the single cell scale.

Consequence alimentary reconstruction in nutritional status after total gastrectomy for gastric cancer.

AIM:To investigate the effect of gastroenteric reconstruction on the nutritional status of patients with gastric cancer after total gastrectomy.METHODS: From 1989-1994, nutritional status was studied in 24 patients, including 12 patients with the gastric reservoir and pyloric sphincter reconstruction (GRPS), 7 with Braun's esophago-jejunostomy (EJ) and 5 with Lawrance's Roux en Y reconstruction (RY).The ability of these patients to ingest and absorb the amount of nutrients was examined and compared, and metabolic balance test was performed to compare the efficiency of those patients to accumulate and use the absorbed nutrients.RESULTS:In the controlled hospital situation, the amount of food ingested by all the patients was greater than that required for maintenance of ideal body weight. In direct contrast, food intake in most patients with EJ or RY reconstruction significantly decreased when the patients returned home and that in EJ patients it was the lowest. The overgrowth of anaerobic bacteria was found in the jejunum in the patients with EJ and RY, due mainly to food stasis in the duodenum or in the Roux limb,caused by the operative procedure itself. In patients with GRPS,because of restoring of the alimentary continuity according to the normal digestive physiologic characters, all the nutritional parameters could fall in the normal range.CONCLUSION:The most common mechanism responsible for postoperative malnutrition was inadequate food intake. Having solved the problem of alkaline reflux esophagitis, it is imperative to preserve the duodenal food passage to reduce malabsorption and other complications after total gastrectomy.