Rational design of eukaryotic riboswitches that up-regulate IRES-mediated translation initiation with high switching efficiency through a kinetic trapping mechanism in vitro.

In general, riboswitches functioning through a cotranscriptional kinetic trapping mechanism (kt-riboswitches) show higher switching efficiencies in response to practical concentrations of their ligand molecules than eq-riboswitches, which function by an equilibrium mechanism. However, the former have been much more difficult to design due to their more complex mechanism. We here successfully developed a rational strategy for constructing eukaryotic kt-riboswitches that ligand-dependently enhance translation initiation mediated by an internal ribosome entry site (IRES). This was achieved both by utilizing some predicted structural features of a highly efficient bacterial kt-riboswitch identified through screening and by completely decoupling an aptamer domain from the IRES. Three kt-riboswitches optimized through this strategy, each responding to a different ligand, exhibited three- to sevenfold higher induction ratios (up to ∼90) than previously optimized eq-riboswitches regulating the same IRES-mediated translation in wheat germ extract. Because the IRES used functions well in various eukaryotic expression systems, these types of kt-riboswitches are expected to serve as major eukaryotic gene regulators based on RNA. In addition, the present strategy could be applied to the rational construction of other types of kt-riboswitches, including those functioning in bacterial expression systems.

Novel insight into the correlation between hernia orifice of cystocele and lower urinary tract function: a pilot study.

BACKGROUND: It has been hypothesized that women with significant pelvic organ prolapse (POP), particularly of the anterior vaginal wall, may have voiding dysfunction (VD). Although the VD mechanism due to cystocele is not fully understood, different vaginal compartments have rarely been closely examined. This study attempted to further elucidate the correlation between POP and VD through a new subgroup classification using cystoscopy. METHODS: This study reviewed clinical records of 49 women who underwent cystocele repair. All patients were scheduled for laparoscopic sacrocolpopexy, preoperatively underwent uroflowmetry and postvoid residual urine volume (PVR) measurement, and completed pelvic floor function questionnaires. Bladder examination by cystoscopy was additionally performed using the lithotomy position with the Valsalva maneuver. RESULTS: Subjects were divided into four groups according to hernia orifice presence determined by cystoscopy, which included the trigone type, posterior wall type, trigone and urethra type, and trigone and posterior wall type. The posterior wall type had statistically higher PVR values versus the trigone and posterior wall type (P = 0.013). The posterior wall type had statistically lower values for average urine flow rate versus the urethra and trigone type (P = 0.020). There were no significant differences noted in the pelvic floor function questionnaires among the four groups. CONCLUSIONS: A new bladder defect classification based upon hernia orifice location was associated with lower urinary tract function. Posterior wall hernia presence caused significant voiding function deterioration. This new subgroup classification, which can more clearly identify and indicate bladder function, is also comparable among patients.

The PD-1/PD-L1 axis may be aberrantly activated in occupational cholangiocarcinoma.

An outbreak of cholangiocarcinoma in a printing company was reported in Japan, and these cases were regarded as an occupational disease (occupational cholangiocarcinoma). This study examined the expression status of programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) in occupational cholangiocarcinoma. Immunostaining of PD-1, PD-L1, CD3, CD8, and CD163 was performed using tissue sections of occupational cholangiocarcinoma (n = 10), and the results were compared with those of control cases consisting of intrahepatic (n = 23) and extrahepatic (n = 45) cholangiocarcinoma. Carcinoma cells expressed PD-L1 in all cases of occupational cholangiocarcinoma, whereas the detection of PD-L1 expression in cholangiocarcinoma cells was limited to a low number of cases (less than 10%) in the control subjects. In cases of occupational cholangiocarcinoma, occasional PD-L1 expression was also noted in precancerous/preinvasive lesions such as biliary intraepithelial neoplasia and intraductal papillary neoplasm of the bile duct. Additionally, tumor-associated macrophages and tumor-infiltrating T cells expressed PD-L1 and PD-1, respectively. The number of PD-L1-positive mononuclear cells, PD-1-positive lymphocytes, and CD8-positive lymphocytes infiltrating within the tumor was significantly higher in occupational cholangiocarcinoma compared with that in control cases. These results indicate that immune escape via the PD-1/PD-L1 axis may be occurring in occupational cholangiocarcinoma.

Development of a multiple-field-of-view multiple-scattering polarization lidar: comparison with cloud radar.

We developed a multiple-field-of-view multiple-scattering polarization lidar (MFMSPL) to study the microphysics of optically thick clouds. Designed to measure enhanced backscattering and depolarization ratio comparable to space-borne lidar, the system consists of four sets of parallel and perpendicular channels mounted with different zenith angles. Depolarization ratios from water clouds were large as observed by MFMSPL compared to those observed by conventional lidar. Cloud top heights and depolarization ratios tended to be larger for outer MFMSPL channels than for vertically pointing channels. Co-located 95 GHz cloud radar and MFMSPL observations showed reasonable agreement at the observed cloud top height.

Cell-Free Biosensors Based on Modular Eukaryotic Riboswitches That Function in One Pot at Ambient Temperature.

Artificial riboswitches responsive to user-defined analytes can be constructed by successfully inserting in vitro selected aptamers, which bind to the analytes, into untranslated regions of mRNA. Among them, eukaryotic riboswitches are more promising as biosensors than bacterial ones because they function well at ambient temperature. In addition, cell-free expression systems allow the broader use of these riboswitches as cell-free biosensors in an environmentally friendly manner without cellular limitations. The current best cell-free eukaryotic riboswitch regulates eukaryotic canonical translation initiation through self-cleavage mediated by an implanted analyte-responsive ribozyme (i.e., an aptazyme, an aptamer-ribozyme fusion). However, it has critical flaws as a sensor: due to the less-active ribozyme used, self-cleavage and translation reactions must be conducted separately and sequentially, and a different aptazyme has to be selected to change the analyte specificity, even if an aptamer for the next analyte is available. We here stepwise engineered novel types of cell-free eukaryotic riboswitches that harness highly active self-cleavage and thus require no reaction partitioning. Despite the single-step and one-pot reaction, these riboswitches showed higher analyte dose dependency and sensitivities than the current best cell-free eukaryotic riboswitch requiring multistep reactions. In addition, the analyte specificity can be changed in an extremely facile way, simply by aptamer substitution (and the subsequent simple fine-tuning for giant aptamers). Given that cell-free systems can be lyophilized for storage and transport, the present one-pot and thus easy-to-handle cell-free biosensors utilizing eukaryotic riboswitches are expected to be widely used for on-the-spot sensing of analytes at ambient temperature.

Pathological spectrum of bile duct lesions from chronic bile duct injury to invasive cholangiocarcinoma corresponding to bile duct imaging findings of occupational cholangiocarcinoma.

BACKGROUND: We aimed to identify the pathological characteristics of occupational cholangiocarcinoma. METHODS: We examined the location and distribution of the carcinomas: atypical epithelium including biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the bile duct (IPNB); and chronic bile duct injuries in operative or autopsy liver specimens from 16 patients. We examined the detailed pathological findings and diagnostic imaging of three patients. Immunohistochemical analysis using primary antibodies against γH2AX and S100P was performed. RESULTS: BilIN and chronic bile duct injury were observed in 16 patients, and IPNB or invasive IPNB was observed in 11 patients. BilIN, IPNB, and/or chronic bile duct injury were observed in almost all the large bile ducts. Regional dilatation of the bile ducts without tumor-induced obstruction revealed such pathological changes. Highly positive results for the γH2AX and S100P markers were noted in invasive carcinoma, BilIN, and IPNB, whereas positive results for γH2AX and negative results for S100P were noted in non-neoplastic biliary epithelium. CONCLUSIONS: The carcinogenic process of occupational cholangiocarcinoma comprised chronic bile duct injury and DNA damage in almost all the large bile ducts, along with induction of precancerous lesions and development of invasive carcinoma. Such pathological findings reflected radiological changes on diagnostic imaging.

Outcomes after resection of occupational cholangiocarcinoma.

BACKGROUND: Cholangiocarcinoma caused by exposure to 1,2-dichloropropane and/or dichloromethane is recognized as occupational cholangiocarcinoma. The aim of this study was to investigate the outcomes after resection of occupational cholangiocarcinoma to establish a treatment strategy for this disease. METHODS: Clinicopathological findings and outcomes after surgical intervention in 20 patients with occupational cholangiocarcinoma were investigated. RESULTS: Of 20 the patients, curative resection was performed in 16 patients. Three patients underwent radiation at the stump of the bile ducts. Adjuvant chemotherapy was performed in 12 patients. Biliary intraepithelial neoplasia, intraductal papillary neoplasm of the bile duct, and/or chronic bile duct injury was detected in most subjects. Intraabdominal infection developed after surgery in nine patients. Cholangiocarcinoma recurred in 12 of the 20 patients. The recurrent tumors in five patients developed at a different part of the bile duct from the primary tumor and a second resection was performed in four of these five patients. CONCLUSIONS: The incidence of postoperative complications including intraabdominal infection was high in patients with occupational cholangiocarcinoma. Multicentric recurrence occurred not infrequently after surgery because the bile ducts had a high potential for the development of carcinoma. The aggressive treatment including second resection for the multicentric recurrence appeared to be effective.

Spontaneous esophageal rupture treated with staged operations.

Spontaneous esophageal rupture is a life-threatening entity. Here, a 64-year-old male who presented with sudden onset of severe back pain was diagnosed as having an esophageal rupture to the right pleural cavity. Emergency operation was carried out 16 hours after the onset. The rupture was as large as 7 cm and the surrounding tissue was fragile and necrotic. We performed an esophagectomy as a primary salvage procedure. An esophageal reconstruction was carried out successfully 6 months after the initial operation. Staged operative strategy including esophagectomy is still an important option to treat this kind of high risk patient.

[A case of gastric cancer with multiple liver metastases responding to TS-1].

We report the case of a 58-year-old male with Stage IV gastric cancer accompanied by multiple liver metastases, which responded to chemotherapy using TS-1. The patient was treated with daily oral administration of 120 mg TS-1 for 4 weeks followed by 2 weeks rest as 1 cycle. After 4 cycles, most of the liver metastases had disappeared and serum CEA level was reduced from 140 to 53.9. The patient received chemotherapy at our outpatient clinic for 9 months during which time there was no regrowth after the first treatment. The current case suggests that TS-1 may have a potent therapeutic efficacy in cases of advanced gastric cancer.

[A case report of both CAF and docetaxel-resistant breast cancer responding to paclitaxel weekly therapy].

A 58-year-old woman underwent CAF and docetaxel therapy for lung, liver and bone metastases from breast cancer operated on 14 years ago. Because of progressive disease due to secondary resistance to CAF and docetaxel, the patient was given three courses of paclitaxel therapy (60 mg/m2, day 1, 8, 15, repeated every 4 weeks). The paclitaxel weekly therapy brought about no adverse effects and remarkable effects against lung and liver metastases (PR). Although the duration of the response to the paclitaxel therapy was limited to about two months due to the progression of skull bone metastasis, paclitaxel weekly therapy may be effective against both CAF and docetaxel-resistant breast cancer.

[Clinical study of weekly administration of paclitaxel for advanced and metastatic gastric cancer].

Ten cases of advanced and metastatic gastric cancer treated by weekly administration of paclitaxel were studied. The patients were 50-72 years of age, including 9 men and 1 woman. In this study, paclitaxel was administered by 1 hour intravenous infusion at a dose of 50-80 mg/m2 every week. Administration was continued for 3 weeks with 1 week rest. One to four cycles were performed at minimum. Paclitaxel was administered in 5 cases as 1st line treatment, 4 cases as 2nd line treatment and 1 case as 3rd line treatment. There were 2 partial responders and no complete responders, and the overall response rate was 20%. The response rate was 100% in liver, 100% in lung, 16% in lymphnodes, and 0% in peritonial dissemination. The clinical symptoms of pain and jaundice abated in one case, the size of the tumor decreased in one case, and a temporary decrease of ascites due to peritonial dissemination was seen in two cases. The level of tumor marker was decreased in 3 out of 10 cases. Side effects included grade 3/4 leukopenia in 10% of patients, and alopecia in 50%, but peripheral neuropathy was not observed. Weekly administration of paclitaxel appears to be well-tolerated and effective against advanced and metastatic gastric cancer.

[Clinical study of weekly paclitaxel administration for metastatic breast cancer based on time to progression (TTP) and survival].

We studied 13 women aged 29-62 years for response to weekly administration of paclitaxel for metastatic breast cancer. Paclitaxel was administered by 1-hour intravenous infusion at a dose of 60-80 mg/m2 once a week. Administration was continued for 3 weeks with a 1-week rest for at least 3 cycles. This was first-line treatment in 1 patient, second-line treatment in 7, and third-line treatment in 5. The overall response rate was 68% among 13 partial responders and there were no complete responders. By recurrence site, the response rate was 71% in the liver, 75% in the lung, 18% in bone, and 67% at local sites. Pain was ameliorated in 4 of 8 patients and local recurrence of tumors decreased in 6 of 8 cases. Tumor markers decreased in 6 of 12 cases. Time to progression reached beyond 6 months in 6 of 13 cases, and was limited to within only 3 months in 6 cases. In terms of survival, 4 of 13 patients who were treated by paclitaxel as a 3rd line treatment for liver or lung metastasis died within 3 months after administration. Weekly administration of paclitaxel appears to be effective against metastatic breast cancer. However, the selection of cases based on the timing of administration is considered to be important to prolong the time to progression and improve survival.

[A case of peritoneal metastasis of gastric cancer responding to TS-1, administered for four consecutive weeks with two-week rests].

We treated a patient with gastric cancer considered to be unresectable due to peritoneal metastasis, who responded remarkably to treatment with TS-1. The patient was a 62-year-old male. His diagnosis was gastric cancer, for which he underwent surgery on February 22, 2001. Laparotomy disclosed many nodules measuring 2-3 mm in diameter in the abdominal cavity, so rapid pathological tests were conducted during the operation. The test results indicated peritoneal metastasis from gastric cancer. Therefore, simple laparotomy was employed as the best option. On day 13 after surgery, oral administration of TS-1, bid., at a daily dose of 120 mg was commenced. In our outpatient clinic, he was given 3 courses, each comprising 4 weeks' medication and 2 weeks' discontinuation. Subsequently, upper digestive tract endoscopy was performed but only scars in the gastric vestibular area were observed. Biopsy could not detect any malignant findings. Medication was discontinued due to the patient's preference and he died of gastric cancer 10 months after operation.

Different carcinogenic process in cholangiocarcinoma cases epidemically developing among workers of a printing company in Japan.

Recently, cholangiocarcinoma has epidemically developed among young adult workers of a printing company in Japan. Exposure to organic solvents including 1,2-dichloropropane and/or dichloromethane is supposed to be associated with the carcinoma development. The metabolism of dichloromethane proceeds through a Theta-class glutathione S-transferase (GST) T1-1-catalyzed pathway, where its reactive intermediates have been implicated in genotoxicity and carcinogenicity. This study examined features of the carcinogenic process of the cholangiocarcinoma developed in the printing company. Surgically resected specimens of the cholangiocarcinoma cases were analyzed, where all cases were associated with precursor lesions such as biliary intraepithelial neoplasia (BilIN) and/or intraductal papillary neoplasm of the bile duct (IPNB). Immunohistochemical analysis confirmed constitutional expression of GST T1-1 in normal hepatobiliary tract. Immunostaining of γ-H2AX, a marker of DNA double strand break, showed that its expression was significantly increased in foci of BilIN, IPNB and invasive carcinoma as well as in non-neoplastic biliary epithelial cells of the printing company cases when compared to that of control groups. In the printing company cases, immunohistochemical expression of p53 was observed in non-neoplastic biliary epithelial cells and BilIN-1. Mutations of KRAS and GNAS were detected in foci of BilIN in one out of 3 cases of the printing company. These results revealed different carcinogenic process of the printing company cases, suggesting that the exposed organic solvents might act as a carcinogen for biliary epithelial cells by causing DNA damage, thereby contributing to the carcinoma development.

Case series of 17 patients with cholangiocarcinoma among young adult workers of a printing company in Japan.

BACKGROUND: An outbreak of cholangiocarcinoma occurred among workers in the offset color proof-printing department at a printing company in Japan. The aim of this study was to clarify the characteristics of the patients with cholangiocarcinoma. METHODS: This was a retrospective study conducted in 13 Japanese hospitals between 1996 to 2013. The clinicopathological findings of cholangiocarcinoma developed in 17 of 111 former or current workers in the department were investigated. Most workers were relatively young. RESULTS: The cholangiocarcinoma was diagnosed at 25-45 years old. They were exposed to chemicals, including dichloromethane and 1,2-dichloropropane. The serum γ-glutamyl transpeptidase activity was elevated in all patients. Dilated intrahepatic bile ducts without tumor-induced obstruction were observed in five patients. The cholangiocarcinomas arose from the large bile ducts. The precancerous or early cancerous lesions, such as biliary intraepithelial neoplasia and intraductal papillary neoplasm of the bile ducts, as well as non-specific bile duct injuries, such as fibrosis, were observed in various sites of the bile ducts in all eight patients for whom operative specimens were available. CONCLUSIONS: The present results showed that cholangiocarcinomas occurred at a high incidence in relatively young workers of a printing company, who were exposed to chemicals including chlorinated organic solvents.

Long-term survival and prognostic factors in the surgical treatment for intrahepatic cholangiocarcinoma.

BACKGROUND/PURPOSE: We retrospectively investigated the clinicopathologic features and outcome of 51 patients who underwent hepatectomy for intrahepatic cholangiocellular carcinoma (ICC) between 1991 and 2000, and we also analyzed the potential prognostic factors for long-term survival. METHODS: There were 27 men and 24 women, with a mean age of 63.7 years. The surgical procedures were extended right or left hepatectomy (15 cases), right or left hepatectomy (19 cases), bisegmentectomy (3 cases), segmentectomy (7 cases), and subsegmentectomy (7 cases). The macroscopic findings of the excised tumor showed the mass-forming (MF) type (31 cases), the periductal-infiltrating (PI) type (13 cases), and the intraductal growth (IG) type (7 cases). RESULTS: The patients with the MF type had a significantly higher incidence of lymph node metastasis (44.8%), as compared to those with the PI or IG type (15.0%). Two patients who died of hepatic failure during their hospital stay were excluded from this survival study. The cumulative 1-, 3-, and 5-year survival rates in 49 patients who underwent liver resection were 68.2%, 44.1%, and 32.4%, respectively. The patients with the IG type had the best outcome, followed by those with the PI type and MF type. The survival rates with or without lymph node metastasis were 9.0% and 60.6% at 3 years, and 9.0% and 42.9% at 5 years, respectively ( P << 0.05). The 1-, 2-, and 3-year survival rates in the MF-type patients with lymph node metastasis were 25.4%, 16.9%, and 0%, respectively. Eight patients (15.7%) survived for more than 5 years after operation. The gross appearance of these tumors was the PI type in 5 patients, the IG type in 2, and the IG + MF type in 1. Except for one case with the PI-type tumor, lymph node metastasis was not observed. All of the 5-year survivors underwent curative resection and none of them had any positive surgical margin. CONCLUSION: Analysis of the clinicopathologic factors influencing the survival after surgical treatment showed that the macroscopic type, surgical curability, lymph node metastasis, tumor size, and cancer-free margin were the most predictive.

Overexpression of the Wilms' tumor gene WT1 in pancreatic ductal adenocarcinoma.

The expression of the Wilms' tumor gene WT1 was examined by immunohistochemistry in 40 cases of pancreatic ductal adenocarcinoma. WT1 protein was expressed in 30 (75%) of the 40 pancreatic ductal adenocarcinomas, but not in the remaining 10 (25%). In normal pancreatic ductal cells, WT1 protein was undetectable. No correlations between WT1 expression and clinicopathological parameters such as age, sex, T or N stage, tumor location, and tumor differentiation were observed. Treatment with WT1 antisense oligomers significantly inhibited the growth of five human pancreatic cancer cell lines, PSN1, MiaPaCa2, ASPC1, BxPC3, and PCI6, expressing the WT1 gene. These results indicate an important role of the WT1 gene in the tumorigenesis of pancreatic ductal adenocarcinoma expressing WT1 and provide a rationale for new treatment strategies to treat pancreatic ductal adenocarcinoma by targeting the WT1 gene and its product.