Characteristics of the Gut Microbiome of Healthy Young Male Soldiers in South Korea: The Effects of Smoking

Background/Aims@#South Korean soldiers are exposed to similar environmental factors. In this study, we sought to evaluate the gut microbiome of healthy young male soldiers (HYMS) and to identify the primary factors influencing the microbiome composition. @*Methods@#We prospectively collected stool from 100 HYMS and performed next-generation sequencing of the 16S rRNA genes of fecal bacteria. Clinical data, including data relating to the diet, smoking, drinking, and exercise, were collected. @*Results@#The relative abundances of the bacterial phyla Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria were 72.3%, 14.5%, 8.9%, and 4.0%, respectively. Fifteen species, most of which belonged to Firmicutes (87%), were detected in all examined subjects. Using cluster analysis, we found that the subjects could be divided into the two enterotypes based on the gut microbiome bacterial composition. Compared with enterotype 2 subjects, subjects classified as enterotype 1 tended to be characterized by higher frequencies of potentially harmful lifestyle habits (current smoker: 55.6% vs 36.6%, p=0.222; heavy drinker: 16.7% vs 3.7%, p=0.120; insufficient physical activity: 27.8% vs 14.6%, p=0.318). We identified a significant difference in the microbiome compositions of current and noncurrent smokers (p=0.008); the former differed from the latter mainly in a relatively lower abundance of Bifidobacterium species and a higher abundance of Negativicutes. @*Conclusions@#A high abundance of Actinobacteria and low abundance of Bacteroidetes

Clinicopathologic Analysis of Gastric Carcinoma Patients with Outlet Obstruction

PURPOSE: This study was conducted to analyze the clinical course of patients of gastric cancer with outlet obstruction by comparing them with the gastric cancer patients without outlet obstruction. METHODS: The records of gastric cancer patients with outlet obstruction and who underwent radical gastrectomy from January 1996 to December 2005 were retrospectively reviewed and compared with those patients with gastric cancer and who were without outlet obstruction. RESULTS: The number of the patients who underwent radical gastrectomy was 461. Out of 461 patients, the number of gastric cancer patients with outlet obstruction was 42 (9.1%), and they had nasogastric tube insertion for an average of 4.4 days before operation. These patients showed several significant features such as large tumor size, advanced stage, an increased the number of involved LNs, a low serum albumin level, a frequent antral tumor location and duodenal invasion. There was no difference in complication rates between the two groups, but a higher mortality rate was noted in the gastric cancer patients with outlet obstruction than that in the other patients (P=0.038). The survival rate after the operation was significantly lower among the gastric cancer patients with outlet obstruction (P=0.0008), whereas no difference was found in the survival rate between the above two groups at the same stage (P=0.1951). CONCLUSION: The gastric cancer patients with outlet obstruction showed a comparatively poorer prognosis than those gastric cancer patients without outlet obstruction. However, there was no significant difference in the complication rate and the survival rate for both types of patients who were at the same stage. These results suggest that the patients with outlet obstruction can show the same result as the patients without outlet obstruction by undergoing radical gastrectomy.

A Comparison of Peripheral Doses Scattered from a Physical Wedge and an Enhanced Dynamic Wedge / 의학물리

In order to evaluate the radio-protective advantage of an enhanced dynamic wedge (EDW) over a physical wedge (PW), we measured peripheral doses scattered from both types of wedges using a 2D array of ion-chambers. A 2D array of ion-chambers was used for this purpose. In order to confirm the accuracy of the device, we first compared measured profiles of open fields with the profiles calculated by our commissioned treatment planning system. Then, we measured peripheral doses for the wedge angles of 15 degrees, 30 degrees, 45 degrees, and 60 degrees at source to surface distances (SSD) of 80 cm and 90 cm. The measured points were located at 0.5 cm depth from 1 cm to 5 cm outside of the field edge. In addition, the measurements were repeated by using thermoluminescence dosimeters (TLD). The peripheral doses of EDW were (1.4% to 11.9%) lower than those of PW (2.5% to 12.4%). At 15 MV energy, the average peripheral doses of both wedges were 2.9% higher than those at 6MV energy. At a small SSD (80 cm vs. 90 cm), peripheral dose differences were more recognizable. The average peripheral doses to the heel direction were 0.9% lower than those to the toe direction. The results from the TLD measurements confirmed these findings with similar tendency. Dynamic wedges can reduce unnecessary scattered doses to normal tissues outside of the field edge in many clinical situations. Such an advantage is more profound in the treatment of steeper wedge angles, and shorter SSD.