ABSTRACT: BACKGROUND: Bacteria release a wide variety of small molecules including cell-to-cell signaling compounds. Gram-negative bacteria use a variety of self-produced autoinducers such as acylated homoserine lactones (acyl-HSLs) as signal compounds for quorum sensing (QS) within and between bacterial species. QS plays a significant role in the pathogenesis of infectious diseases and in beneficial symbiosis by responding to acyl-HSLs in Pseudomonas aeruginosa. It is considered that the selection of bacterial languages is necessary to regulate gene expression and thus it leads to the regulation of virulence and provides a growth advantage in several environments. In this study, we hypothesized that MexAB-OprM of P. aeruginosa might function in the selection of acyl-HSLs, and we provide evidence to support this hypothesis. RESULTS: Loss of MexAB-OprM due to deletion of mexB caused increases in QS responses, as shown by the expression of gfp located downstream of the lasB promoter and LasB elastase activity, which is regulated by a LasR-3-oxo-C12-HSL complex. Either complementation with a plasmid containing wild-type mexB or the addition of a LasR-specific inhibitor, patulin, repressed these high responses to 3-oxo-acyl-HSLs. Furthermore, it was shown that the acyl-HSLs-dependent response of P. aeruginosa was affected by the inhibition of MexB transport activity and the mexB mutant. The P. aeruginosa MexAB-OprM deletion mutant showed a strong QS response to 3-oxo-C10-HSL produced by Vibrio anguillarum in a bacterial cross-talk experiment. CONCLUSION: This work demonstrated that MexAB-OprM does not control the binding of LasR to 3-oxo-Cn-HSLs but rather accessibility of non-cognate acyl-HSLs to LasR in P. aeruginosa. MexAB-OprM not only influences multidrug resistance, but also selects acyl-HSLs and regulates QS in P. aeruginosa. The results demonstrate a new QS regulation mechanism via the efflux system MexAB-OprM in P. aeruginosa.

Purpose. To assess differences in dose distribution of a vertebral body injected with bone cement as calculated by radiation treatment planning system (RTPS) and actual dose distribution. Methods. We prepared two water-equivalent phantoms with cement, and the other two phantoms without cement. The bulk density of the bone cement was imported into RTPS to reduce error from high CT values. A dose distribution map for the phantoms with and without cement was calculated using RTPS with clinical setting and with the bulk density importing. Actual dose distribution was measured by the film density. Dose distribution as calculated by RTPS was compared to the dose distribution measured by the film dosimetry. Results. For the phantom with cement, dose distribution was distorted for the areas corresponding to inside the cement and on the ventral side of the cement. However, dose distribution based on film dosimetry was undistorted behind the cement and dose increases were seen inside cement and around the cement. With the equivalent phantom with bone cement, differences were seen between dose distribution calculated by RTPS and that measured by the film dosimetry. Conclusion. The dose distribution of an area containing bone cement calculated using RTPS differs from actual dose distribution.

Recently, prone position esophagectomy for esophageal cancer is thought to be an easier and safer procedure. Here, we introduced prone position for enucleation of the fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) positive esophageal leiomyoma. The patient was a 47-year-old man with a 4 cm mid-thoracic esophageal submucosal tumor. The tumor was enucleated safely without injury of the esophageal mucosa under the gravity effect of the prone position with use of a sponge spacer and Sengstaken-Blakemore balloon. Postoperative examination revealed that the tumor was a leiomyoma that was positive for smooth muscle actin and negative for CD117. Postoperative course was uneventful and the patient was discharged on day 7 after the operation. The prone position with use of a sponge spacer and Sengstaken-Blakemore balloon was a safer and easier procedure for the enucleation of the esophageal submucosal tumor.

BACKGROUND: Adequate blood supply for the reconstructed organ is important for safe esophagogastric anastomosis during esophagectomy. Recently, indocyanine green (ICG) has been used for visualization of the blood supply when anastomosis is performed in vascular surgery. To visualize the blood supply for reconstruction, we employed ICG fluorescence during esophagectomy. METHODS: From August 2008, 40 patients received cervical or thoracic esophagectomy. They consisted of 33 patients having esophagectomy for thoracic esophageal cancer, 3 being treated for cervical esophageal cancer, and 4 with double cancer of the thoracic and cervical regions. Before and after pulling up the reconstructed organ, 2.5 mg of ICG was injected as a bolus. Then ICG fluorescence was detected by a camera and recorded. RESULTS: ICG fluorescence was easily detected in all patients at 1 min after injection. The vascular network was well visualized in the gastric wall, colonic grafts, and free jejunal grafts. In five patients, we also performed anastomosis between the short gastric vein and the external cervical vein or superficial cervical vein. The intraoperative and postoperative course of all patients was uneventful apart from three anastomotic leakages. CONCLUSIONS: ICG fluorescence can be employed to evaluate the blood supply to reconstructed organs and can be useful in selecting the patients who do not need additional vessel anastomosis. However, anastomotic leakage was not reduced, so the microcirculation detected by ICG fluorescence did not necessarily provide appropriate blood supply for a viable anastomosis.

BACKGROUND: Some of the induced pluripotent stem cell (iPS cell)-inducing factors have been reported to be expressed in breast cancer. The aim of the present study was to examine the relationship between the expression of iPS cell-inducing factors and the prognosis of breast cancer patients. METHODS: In 100 breast cancer patients, the expression of c-MYC, KLF4, NANOG, OCT4, and SOX2 was determined by immunohistochemistry using a tissue microarray analysis. RESULTS: Patients with strong expression of NANOG had significantly lower disease-free survival (DFS) and overall survival rates than those with weak expression of NANOG (P = 0.004 and 0.033, respectively). In contrast, patients with strong expression of KLF4 had better DFS (P = 0.014). CONCLUSIONS: Strong expression of NANOG is an indicator of a poor prognosis for breast cancer patients, whereas KLF4 is a favorable prognostic indicator. Our results suggest that NANOG stimulates the growth and metastasis of breast cancer cells, whereas KLF4 inhibits these processes.

Aquaporins (AQPs) are important in controlling bile formation, however, the exact role of AQPs in human biliary tract carcinogenesis has not been clearly defined. In this study, we analyzed AQP-1,-4,-5 and -8 expression immunohistochemically using tissue microarrays (TMAs) in 81 samples.(45 gallbladder carcinomas and 36 bile duct carcinomas). The survival of patients with high AQP-5 expression was longer compared to that of patients with low AQP-5 expression (P=0.017). Cox's proportional hazard model revealed that AQP-5 expression was an independent prognostic factor (RR, 0.38; P=0.025). Chi-square analysis revealed that high AQP-5 expression correlated to small tumor size in biliary tract carcinoma patients (P=0.006). With regard to the expression of other AQPs, depth of tumor invasion, histological type and serum carbohydrate antigen 19-9 (CA19-9) were associated with high AQP-1 expression (P=0.039, 0.011 and 0.032). However, AQP-4 and AQP-8 expression had no association with clinicopathological factors. Among the 10 patients who underwent gemcitabine (GEM) plus S-1 postoperative chemotherapy, the group of patients (n=5) with high AQP-5 expression were associated with higher rates of both overall and disease-free survival (log-rank P=0.033, 0.002). In conclusion, the results of this study suggest that AQP-5 expression may be associated with prognosis and drug sensitivity in biliary tract carcinoma.

BACKGROUND Patients undergoing pulmonary resection often suffer from a dry, hacking cough, which is usually refractory to opioid cough suppressors such as codeine. The cough is often painful and impairs the quality of life of the patients. The efficacy of an inhaled corticosteroid plus β2-agonist against the persistent cough after pulmonary resection was evaluated in this study. METHODS We enrolled 21 patients in this prospective study of the efficacy of an inhaled corticosteroid plus β2-agonist against persistent cough following pulmonary resection. After baseline evaluation of the severity of the postoperative persistent cough using a visual analog scale (VAS), treatment with an inhaled corticosteroid plus β2-agonist was initiated and continued for 2 weeks. At the end of the 2 weeks, the cough severity was evaluated again using a VAS. RESULTS The median grade of cough on the VAS before the start of the inhaled treatment was 4 (range 3-8). At the end of 2 weeks of treatment with an inhaled corticosteroid plus β2 agonist, the median grade of cough on the VAS decreased from 4 to 1 (range 0-4). As an adverse effect of the inhalation, hoarseness was observed in one patient, which disappeared promptly after discontinuing the inhalations. CONCLUSION Treatment with an inhaled corticosteroid plus β2 agonist appeared to be highly effective, without severe adverse effects, against the persistent cough suffered by patients after pulmonary resection.

PURPOSE: To identify factors affecting local control of stereotactic body radiotherapy (SBRT) for lung tumors including primary lung cancer and metastatic lung tumors. MATERIALS AND METHODS: Between June 2006 and June 2009, 159 lung tumors in 144 patients (primary lung cancer, 128; metastatic lung tumor, 31) were treated with SBRT with 48-60 Gy (mean 50.1 Gy) in 4-5 fractions. Higher doses were given to larger tumors and metastatic tumors in principle. Assessed factors were age, gender, tumor origin (primary vs. metastatic), histological subtype, tumor size, tumor appearance (solid vs. ground glass opacity), maximum standardized uptake value of positron emission tomography using (18)F-fluoro-2-deoxy-D:-glucose, and SBRT doses. RESULTS: Follow-up time was 1-60 months (median 18 months). The 1-, 2-, and 3-year local failure-free rates of all lesions were 90, 80, and 77 %, respectively. On univariate analysis, metastatic tumors (p < 0.0001), solid tumors (p = 0.0246), and higher SBRT doses (p = 0.0334) were the statistically significant unfavorable factors for local control. On multivariate analysis, only tumor origin was statistically significant (p = 0.0027). The 2-year local failure-free rates of primary lung cancer and metastatic lung tumors were 87 and 50 %, respectively. CONCLUSIONS: A metastatic tumor was the only independently significant unfavorable factor for local control after SBRT.

BACKGROUND: The 7th edition of the American Joint Committee on Cancer staging system does not include lymph node size in the guidelines for staging patients with esophageal cancer. The objectives of this study were to determine the prognostic impact of the maximum metastatic lymph node diameter (ND) on survival and to develop and validate a new staging system for patients with esophageal squamous cell cancer who were treated with definitive chemoradiotherapy (CRT). METHODS: Information on 402 patients with esophageal cancer undergoing CRT at two institutions was reviewed. Univariate and multivariate analyses of data from one institution were used to assess the impact of clinical factors on survival, and recursive partitioning analysis was performed to develop the new staging classification. To assess its clinical utility, the new classification was validated using data from the second institution. RESULTS: By multivariate analysis, gender, T, N, and ND stages were independently and significantly associated with survival (p < 0.05). The resulting new staging classification was based on the T and ND. The four new stages led to good separation of survival curves in both the developmental and validation datasets (p < 0.05). CONCLUSIONS: Our results showed that lymph node size is a strong independent prognostic factor and that the new staging system, which incorporated lymph node size, provided good prognostic power, and discriminated effectively for patients with esophageal cancer undergoing CRT.

Abstract Introduction:This study aimed to analyze factors influencing accuracy and complications in patients who underwent computed tomography (CT)-guided lung biopsy at our medical center. Material and methods: This study included all 107 patients (72 men, 35 women; mean age, 69 years; range, 41-83 years) who underwent CT-guided lung biopsy between January 2006 and October 2009. CT fluoroscopy was used in 45.7% of cases. Final diagnosis, when surgical resection was performed, was histopathological diagnosis from the lung lesion specimen, and when resection was not performed, clinical diagnosis after ≥ 6 months of follow-up. The accuracy of lung biopsy was assessed by comparison of biopsy results and final diagnosis. The influence of factors on accuracy was statistically analyzed. Results:Accuracy of CT-guided lung biopsy was 89.4%. None of the factors, including lesion size, lesion depth from pleura, lesion location, patient position, final diagnosis, and use or non-use of CT fluoroscopy, had any significant influence on accuracy. The only complications were Grade 1 and 2 pneumothorax and Grade 1 pulmonary bleeding. The incidence of pneumothorax and bleeding was significantly increased with smaller lesion size and significantly increased with greater lesion depth. In patients with pulmonary emphysema, bleeding was significantly less (p = 0.022). When CT fluoroscopy was used, bleeding was significantly increased (p < 0.001). Conclusions:None of the factors had any significant influence on accuracy. The incidence of pneumothorax and bleeding was affected by lesion size and lesion depth. When CT fluoroscopy was used, bleeding was significantly increased.