Vapor growth of CdS nanowires/WS2 nanosheet heterostructures with sensitive photodetections.

Heterostructures based on two-dimensional (2D) transition metal dichalcogenides semiconductors are reported to be promising building-blocks for next-generation integrated optoelectronic systems, owing to their atomic thin interface and interface-induced properties. Previously reported works have mostly been directed to focus on the 2D/2D heterostructures, and their optoelectronic performance is still inferior to the expectations for practical applications, mainly attributed to their non-ideal optical absorption when the thickness is confined at atomic scale. In this work, we have reported on high sensitivity photodetectors based on one-dimensional (1D)/2D heterostructures consisting of CdS nanowire and WS2 nanosheets grown by direct chemical vapor deposition. The components of the heterostructures were confirmed by x-ray diffraction, x-ray photoelectron spectroscopy, transmission electron microscope, photoluminescence and Raman spectra measurements, confirming the high quality heterostructures. Photodetectors were then fabricated based on the as-synthesized CdS/WS2 heterostructures, showing superior photodetection performances with a photoresponsivity of ∼50 A W-1 and an ultrahigh photodetectivity of ∼1012 Jones. Much higher responsivity of 5472 A W-1 and detectivity of 5 × 1013 Jones can be achieved through applying back gate voltage. The direct growth of such 1D/2D heterostructures may pave the way toward high performance integrated optoelectronics and systems.

Branched CdO/ZnO Core/Shell Heterogeneous Structure and Its Enhanced Photoelectrocatalytic Performance.

Branched nanostructures of semiconductors based on one-dimensional heterostructures have many promising applications in optoelectronics, supercapacitors, photocatalysts, etc. Here, we report a novel branched core/shell CdO/ZnO hetero-nanostructure that resembles a Crimson bottlebrush (Callistemon Citrinus) but with intriguing hexagonal symmetry. The nanomaterials were fabricated via an improved one-step chemical vapor deposition method and consist of a CdO wire as the core and ZnO as the shell. With cadmium acting as a catalyst, ZnO nanowires grow as perpendicular branches from the CdO/ZnO one-dimensional core/shell structure. The nanostructures were characterized with X-ray diffraction scanning and transmission electron microscopy. A homogeneous epitaxial growth mechanism has been postulated for the formation of the nanostructure. The materials show a broad and strong absorption ranging from visible to ultraviolet and a better photoelectrocatalytic properties in comparison to pure ZnO or CdO. Our synthetic strategy may open up a new way for controlled preparation of one-dimensional nanomaterials with core/shell heterostructure, which could find potential applications in solar cells and opto-electrochemical water-splitting devices.

Nonlinear photoluminescence in monolayer WS2: parabolic emission and excitation fluence-dependent recombination dynamics.

Recombination dynamics during photoluminescence (PL) in two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) are complicated and can be easily affected by the surroundings because of their atomically thin structures. Herein, we studied the excitation power and temperature dependence of the recombination dynamics on the chemical vapor deposition-grown monolayer WS2via a combination of Raman, PL, and time-resolved PL spectroscopies. We found a red shift and parabolic intensity increase in the PL emission of the monolayer WS2 with the increasing excitation power and the decay time constants corresponding to the recombination of trions and excitons from transient PL dynamics. We attributed the abovementioned nonlinear changes in the PL peak positions and intensities to the combination of increasing carrier interaction and band structure renormalization rather than to the thermal effect from a laser. Furthermore, the excitation power-dependent Raman measurements support our conclusion. These findings and understanding will provide important information for the development of TMD-based optoelectronics and photonics.

Infusion of Bone Marrow Mesenchymal Stem Cells Attenuates Experimental Severe Acute Pancreatitis in Rats.

Background & Aims. Severe acute pancreatitis (SAP) remains a high-mortality disease. Bone marrow (BM) mesenchymal stem cells (MSCs) have been demonstrated to have plasticity of transdifferentiation and to have immunomodulatory functions. In the present study, we assessed the roles of MSCs in SAP and the therapeutic effects of MSC on SAP after transplantation. Methods. A pancreatitis rat model was induced by the injection of taurocholic acid (TCA) into the pancreatic duct. After isolation and characterization of MSC from BM, MSC transplantation was conducted 24 hrs after SAP induction by tail vein injection. The survival rate was observed and MSCs were traced after transplantation. The expression of TNF-α and IL-1ß mRNA in the transplantation group was also analyzed. Results. The survival rate of the transplantation group was significantly higher compared to the control group (p < 0.05). Infused MSCs were detected in the pancreas and BM 3 days after transplantation. The expression of TNF-α and IL-1ß mRNA in the transplantation group was significantly lower than in the control group in both the pancreas and the lungs (p < 0.05). Conclusions. MSC transplantation could improve the prognosis of SAP rats. Engrafted MSCs have the capacity of homing, migration, and planting during the treatment of SAP.

Bulk pancreatic cancer cells can convert into cancer stem cells(CSCs) in vitro and 2 compounds can target these CSCs.

Increasing evidence has confirmed the existence of cancer stem cells (CSCs) in both hematological malignancies and solid tumors. However, the origin of CSCs is still uncertain, and few agents have been capable of eliminating CSCs till now. The aim of this study was to investigate whether bulk pancreatic cancer cells could convert into CSCs under certain conditions and explore whether metformin and curcumin can kill pancreatic CSCs. Aspc1, Bxpc3 and Panc1 pancreatic cancer cells were cultured in stem cell culture medium (serum-free Dulbecco's modified Eagle medium/Nutrient Mixture F-12 containing basic fibroblast growth factor, epidermal growth factor, B27 and insulin) for 5 days and it was found that all the pancreatic cancer cells aggregated into spheres and expressed pancreatic cancer stem cell surface markers. Then characteristics of Panc1 sphere cells were analyzed and cytotoxicity assays were performed. The results show that Panc1 sphere cells exhibited CSC characteristics and were more resistant to conventional chemotherapy and more sensitive to metformin and curcumin than their parent cells. These findings suggested that bulk pancreatic cancer cells could acquire CSC characteristics under certain conditions, which may support the "yin-yang" model of CSCs (interconversion between bulk cancer cells and CSCs). These results also showed that metformin and curcumin could be candidate drugs for targeting pancreatic CSCs.

[Bioretention Media Screening for the Removal of Phosphorus in Urban Stormwater].

Urban runoff is an increasingly important source of excess phosphorus (P) to local receiving waters. Bioretention, a promising technology for urban stormwater pollution treatment, was investigated to determine whether the mixture of purple soil and sand could adsorb sufficient P at low concentrations in urban stormwater. The TP concentrations of urban runoff from variously impervious areas in Chongqing City ranged from 0. 04 to 7. 00 mg . L-1 (mean ± S. D. = 0. 75 mg . L-1 ± 1. 08 mg . L-1); the TDP concentrations ranged from 0. 02-0. 46 mg . L-1 ( mean ± S. D. = 0. 15 mg . L-1 ± 0. 10 mg . L-1). The media adsorption benchmark was determined for a bioretention facility sized at 10% of the 100% impervious catchment area and having 10 years of capacity according to annual rainfall pattern and the runoff TDP range. The media benchmark for adsorption was calculated as 7. 5 mg . kg-1 at soluble P concentration of 0. 30 mg . L-1 which provided the necessary stormwater treatment. The oxalate-extractable aluminum and iron content influenced the P sorption capacity for neutral and acid purple soils. A strong positive linear relationship was observed between the oxalate ratio [OR = (Alox + Feox)/Pox] and media P sorption capacity. The media mixture of 20% purple soil and 80% sand showed excellent P removal, meeting the developed benchmark for adsorptive behavior. The media mixture in a large-scale (60 cm) column consistently produced soluble reactive phosphorus effluent event with mean concentrations <0. 05 mg . L-1. The media mixture of purple soil and sand can be used as a bioretention media to treat low-concentration phosphorus in urban runoff under various hydrologic and pollutant concentration conditions.

Aberrant expression miR-196a is associated with abnormal apoptosis, invasion, and proliferation of pancreatic cancer cells.

OBJECTIVES: MiR-196a levels inversely correlated with survival in pancreatic adenocarcinoma patients. However, the functional contributions of miR-196a to pancreatic cancer remain unclear. METHODS: Three lentiviral vectors encoding microRNA miR-196a precursor, inhibitor, and scrambled microRNA oligomer were transfected into Panc-1 cells, respectively. Then we explored the regulation of inhibitor of growth 5 (ING5) expression by miR-196a and its impact on apoptosis, invasion, and growth of pancreatic cancer cells. The lentiviral transfected Panc-1 cells were surgically implanted into the pancreas of mice. In vivo tumor growth and ING5 expression were measured. RESULTS: Down-regulation of ING5 expression was detected in cells transfected with miR-196a precursor (P < 0.01), accompanied by less apoptosis, increased invasion, and proliferation compared with control cells (P < 0.05). Cells transfected with miR-196a inhibitor revealed an opposite trend. Smaller detectable tumors were found in only 60% of mice after implantation of Lenti.miR-196a inhibitor-transfected Panc-1 cells compared with controls (360.7 ± 303.6 mm vs 511.58 ± 365.9 mm in controls; P < 0.01). CONCLUSION: Our results provide experimental evidence to support aberrant expression of miR-196a is associated with abnormal apoptosis, invasion, and proliferation of pancreatic cancer cells.

Adenovirus vector-mediated Gli1 siRNA induces growth inhibition and apoptosis in human pancreatic cancer with Smo-dependent or Smo-independent Hh pathway activation in vitro and in vivo.

Activation of Hedgehog (Hh) signaling pathway is a core molecular mechanism in pancreatic carcinogenesis. However, the inhibition of upstream Hh signals does not inhibit the growth of a subset of pancreatic cancer (PC). This study was to examine the effect of siRNA targeting Gli1, the downstream component of Hh pathway, on PC cells and to provide some insight into the underlying mechanisms. A Gli1siRNA-expressing adenovirus (Ad-U6-Gli1siRNA) was constructed, and its effect on PC cells was investigated in vitro and in vivo. Gli1 was expressed in 83.3% (20/24) PC tissues, whereas no expression was found in normal pancreatic ductal epithelium. Gli1 was expressed in SW1990 and CFPAC cells in which Smo was completely absent, as well as in PaTu8988, Panc-1 and BxPC-3 cells in which Smo was concomitantly present. Ad-U6-Gli1siRNA induced cell growth inhibition, strong G0/G1 cell cycle arrest and apoptosis in all five human PC cell lines. Meanwhile, Ad-U6-Gli1siRNA significantly suppressed the expression of Gli1, Ptch1 and two target genes, Cyclin D2 and Bcl-2, in all five lines. Furthermore, two tumor xenograft nude mice models were established by subcutaneously injecting Smo-positive Panc-1 cells or Smo-negative SW1990 cells. The in vivo experimental results demonstrated that Ad-U6-Gli1siRNA inhibited the growth of both Panc1-derived and SW1990-derived tumors and induced cell apoptosis. Our study indicates that Gli1-targeting siRNA could induce growth inhibition and apoptosis in PC through knockdown of Gli1 and its target genes; and this method may represent a more effective therapeutic strategy for PC with Smo-dependent or Smo-independent Hh pathway activation.

Impact of adjuvant chemotherapy cycles on prognosis of resectable stomach cancer: a retrospective analysis.

AIMS: The aim of this study was to investigate the effects of adjuvant chemotherapy cycles on the prognosis of patients with post-operative stomach cancer through retrospective analysis. METHODS: A total of 128 patients with gastric cancer who underwent gastrectomy, followed by adjuvant chemotherapy consisting of epirubicin, cisplatin or oxaliplatin, leucovorin, and 5-fluorouracil, according to a defined schedule, were divided into three groups according to the number of chemotherapy cycles: Group I (<6 cycles); Group II (6 cycles); and Group III (>6 cycles). RESULTS: The 5-year overall survival (OS) was 20.8% in Group I, 45.0% in Group II, and 42.9% in Group III, with a median follow-up of 43 months. The 5-year relapse-free survival (RFS) was 15.1% in Group I, 40% in Group II, and 40% in Group III. The OS and RFS in Groups II and III were significantly better than in Group I (OS, p = 0.002 and p=0.003; RFS, P<0.001 and P=0.002). There was no difference in OS (p = 0.970) or in RFS (p = 0.722) between Groups II and III. Multivariate Cox hazard analysis determined that the number of adjuvant chemotherapy cycles was an independent factor that influenced OS and RFS. CONCLUSION: Six cycles of adjuvant chemotherapy gave encouraging outcomes in patients with resectable gastric cancer. Further prospective randomized controlled investigations are warranted in a multi-center setting.

Adjuvant probiotics improve the eradication effect of triple therapy for Helicobacter pylori infection.

AIM: To investigate whether the addition of probiotics can improve the eradication effect of triple therapy for Helicobacter pylori (H. pylori) infection. METHODS: This open randomized trial recruited 234 H. pylori positive gastritis patients from seven local centers. The patients were randomized to one-week standard triple therapy (omeprazole 20 mg bid, clarithromycin 500 mg bid, and amoxicillin 1000 mg bid; OCA group, n = 79); two weeks of pre-treatment with probiotics, containing 3 × 10(7)Lactobacillus acidophilus per day, prior to one week of triple therapy (POCA group, n = 78); or one week of triple therapy followed by two weeks of the same probiotics (OCAP group, n = 77). Successful eradication was defined as a negative C13 or C14 urease breath test four weeks after triple therapy. Patients were asked to report associated symptoms at baseline and during follow-up, and side effects related to therapy were recorded. Data were analyzed by both intention-to-treat (ITT) and per-protocol (PP) methods. RESULTS: PP analysis involved 228 patients, 78 in the OCA, 76 in the POCA and 74 in the OCAP group. Successful eradication was observed in 171 patients; by PP analysis, the eradication rates were significantly higher (P = 0.007 each) in the POCA (62/76; 81.6%, 95% CI 72.8%-90.4%) and OCAP (61/74; 82.4%, 95% CI 73.6%-91.2%) groups than in the OCA group (48/78; 61.5%, 95% CI 50.6%-72.4%). ITT analysis also showed that eradication rates were significantly higher in the POCA (62/78; 79.5%, 95% CI 70.4%-88.6%) and OCAP (61/77; 79.2%, 95% CI 70%-88.4%) groups than in the OCA group (48/79; 60.8%, 95% CI 49.9%-71.7%), (P = 0.014 and P = 0.015). The symptom relieving rates in the POCA, OCAP and OCA groups were 85.5%, 89.2% and 87.2%, respectively. Only one of the 228 patients experienced an adverse reaction. CONCLUSION: Administration of probiotics before or after standard triple therapy may improve H. pylori eradication rates.

Gastro-protecting effect of gefarnate on chronic erosive gastritis with dyspeptic symptoms.

BACKGROUND: The role of gastro-protecting agents on symptomatic chronic gastritis is unclear. This multicenter, open, randomized trial was designed to compare the comprehensive effects of gefarnate with sucralfate on erosive gastritis with dyspeptic symptoms. METHODS: Totally 253 dyspepsia patients confirmed with erosive gastritis were enrolled from six centers in China. They randomly received either daily 300 mg gefarnate or 3 g sucralfate for six weeks. The primary endpoint was the effective rate of both treatments on endoscopic erosion at week six. RESULTS: Gefarnate showed an effective rate of 72% and 67% on endoscopic score and dyspeptic symptom release, which is statistically higher than sucralfate (40.1% and 39.3%, P < 0.001, intension-to-treat). For histological improvement, gefarnate showed both effective in decreasing mucosal chronic inflammation (57.7% vs. 24.8%, P < 0.001, intension-to-treat) and active inflammation (36.4% vs. 23.1%, P < 0.05, intension-to-treat) than the control. A significant increase of prostaglandins and decrease of myeloperoxidase in mucosa were observed in gefarnate group. Severity of erosion is non-relevant to symptoms but Helicobacter pylori (H. pylori) status does affect the outcome of therapy. CONCLUSIONS: Gefarnate demonstrates an effective outcome on the mucosal inflammation in patients with chronic erosive gastritis. Endoscopic and inflammation score should be the major indexes used in gastritis-related trials.

Neuronal pentraxin II (NPTX2) is frequently down-regulated by promoter hypermethylation in pancreatic cancers.

BACKGROUND: Gene silencing via promoter hypermethylation plays a crucial role in the pathogenesis of cancers. Neuronal pentraxin II (NPTX2) has been observed to be hypermethylated in pancreatic cancers. Methylation of NPTX2 might provide a novel diagnostic marker for pancreatic cancers. AIM: The objective of this study is to investigate the abnormal patterns of DNA methylation of NPTX2 in pancreatic cancers, and its role in the transcriptional silencing of NPTX2. METHODS: NPTX2 expression was detected by reverse-transcription polymerase chain reaction (RT-PCR), and the methylation status of NPTX2 was assessed by methylation-specific polymerase chain reaction (MSP). Immunohistochemistry was used to examine the NPTX2 protein expression. The pancreatic cancer cell lines were treated with the DNA methyltransferase inhibitor, histone deacetylase inhibitors, either alone or in combination. RESULTS: The MSP analysis revealed that the promoter region of NPTX2 gene was largely unmethylated in normal pancreatic tissues, while NPTX2 was frequently hypermethylated in pancreatic cancer cells and in primary pancreatic carcinomas. Quantitative RT-PCR revealed that the mean mRNA expression level of NPTX2 in the pancreatic cancer tissues was significantly lower than that in the paired adjacent normal tissues (0.96 ± 0.91 vs. 2.78 ± 1.42, P < 0.001). Consistent with RT-PCR detection, treatment with 5Aza-dC resulted in different degrees of induction of NPTX2 protein in the various cancer cell lines. CONCLUSION: We demonstrate that the NPTX2 protein is down-regulated in human primary pancreatic cancers and in pancreatic cancer cell lines. This study provides the first evidence that the down-regulation of NPTX2 tightly correlates with its promoter hypermethylation.

Differential signature of fecal microRNAs in patients with pancreatic cancer.

The potential value of microRNAs as new biomarkers for pancreatic cancer (PCa) screening was explored in this study. Fecal microRNAs from stool samples obtained from 29 PCa patients, 22 chronic pancreatitis (CP) patients and 13 normal individuals were extracted, and 7 microRNAs (miR-16, miR-21, miR-155, miR-181a, miR-181b, miR-196a and miR-210) were detected. miR-181b and miR-210 discriminated PCa from normal individuals with receiver operating characteristic (ROC) curves and area under curve (AUC-ROC) of 0.745 and 0.772, respectively. There was a significant correlation between miR­196a and the maximum tumor diameter (Spearman r = 0.516, P = 0.041). These findings suggest that fecal microRNAs such as miR-181b and miR-210 may have potential to be used as new biomarkers for PCa screening.

Inhibitory effects of intravenous lansoprazole 30 mg and pantoprazole 40 mg twice daily on intragastric acidity in healthy Chinese volunteers: a randomized, open-labeled, two-way crossover study.

BACKGROUND: Until now there has been no study that directly compares the effect of lansoprazole and pantoprazole administered intravenously on intragastric acidity. The aim of this study is to compare the effect of lansoprazole (30 mg) and pantoprazole (40 mg) administered intravenously on gastric acidity. MATERIAL/METHODS: Helicobacter pylori-negative healthy volunteers were recruited in this open-label, randomized, two-way crossover, single centre study. Lansoprazole at 30 mg or pantoprazole at 40 mg was intravenously administered twice daily for 5 consecutive days with at least a 14-day washout interval. Twenty-four-hour intragastric pH was continuously monitored on days 1 and 5 of each dosing period. RESULTS: Twenty-five volunteers completed the 2 dosing periods. The mean intragastric pH values were higher in subjects treated with lansoprazole than those with pantoprazole on both day 1 (6.41 ± 0.14 vs. 5.49 ± 0.13, P=0.0003) and day 5 (7.09 ± 0.07 vs. 6.64 ± 0.07, P=0.0002). Significantly higher percentages of time with intragastric pH >4 and pH >6 were found in the subjects treated with lansoprazole than those with pantoprazole on day 1 (pH >4, 87.12 ± 4.55% vs. 62.28 ± 4.15%, P=0.0012; pH >6, 62.12 ± 4.12% vs. 47.25 ± 3.76%, P=0.0216) and pH >6 on day 5 (76.79 ± 3.77% vs. 58.20 ± 3.77%, P=0.0025). CONCLUSIONS: Intravenous lansoprazole produces a longer and more potent inhibitory effect on intragastric acidity than does intravenous pantoprazole.

Combination of plasma microRNAs with serum CA19-9 for early detection of pancreatic cancer.

This study was performed to identify plasma microRNAs (miRNAs) as diagnostic biomarkers for pancreatic cancer (PCa) and to assess their supplementary role with serum CA19-9 in early identification of tumors. Plasma RNAs were extracted from 140 PCa patients, 111 chronic pancreatitis (CP) patients and 68 normal controls, and the relative abundances of seven miRNAs (miR-16, 21, 155, 181a, 181b, 196a and 210) were measured using real-time PCR. Their diagnostic utility for PCa and correlation with clinical characteristics were analyzed. All seven miRNAs were significantly aberrantly upregulated in the PCa group compared with both the CP and normal groups, between which only four miRNAs (miR-155, 181a, 181b and 196a) were significantly different. Logistic modeling proved that only miR-16 and miR-196a possessed an independent role in discriminating PCa from normal and CP. Furthermore, after including serum CA19-9 in the logistic model, the combination of miR-16, miR-196a and CA19-9 was more effective for discriminating PCa from non-PCa (normal+CP) (AUC-ROC, 0.979; sensitivity, 92.0%; specificity, 95.6%), and for discriminating PCa from CP (AUC-ROC, 0.956; sensitivity, 88.4%; specificity, 96.3%) compared with the miRNA panel (miR-16+miR-196a) or CA19-9 alone. Most significantly, the combination was effective at identification of tumors in Stage 1 (85.2%). In conclusion, plasma miRNAs were effective for distinguishing PCa from non-PCa (normal+CP). The combination of miR-16, miR-196a and CA19-9 was more effective for PCa diagnosis, especially in early tumor screening.

Soluble triggering receptor expressed on myeloid cells in severe acute pancreatitis: a biological marker of infected necrosis.

PURPOSE: The diagnosis and treatment of secondary infection of pancreatic necrotic tissue remain a major challenge. The level of soluble triggering receptor expressed on myeloid cells (sTREM-1) in fine needle aspiration (FNA) fluid may be a good marker of infected necrosis. METHODS: Patients with a clinical suspicion of secondary infection of necrotic tissue were enrolled. The serum levels of C-reactive protein, amylase, procalcitonin (PCT), and sTREM-1 and the fluid levels of sTREM-1, PCT, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and amylase were examined. When infected necrosis was defined, the first step was percutaneous or endoscopic drainage. If there was no improvement after 72 h, an open necrosectomy was performed. RESULTS: In 30 patients with suspected infection, 18 patients were diagnosed as having secondary infection of necrotic tissue. The levels of sTREM-1 and PCT in FNA fluid were found to have the closest correlation with the diagnosis of infected necrosis [sTREM-1: area under the receiver operating characteristic curve (AUC) 0.972; 95% confidence interval (95%CI) 0.837-1.000; PCT: AUC 0.903; 95%CI 0.670-0.990, P > 0.05]. A fluid sTREM-1 cutoff value of 285.6 pg/ml had a sensitivity of 94.4% and a specificity of 91.7%. In a multiple logistic regression analysis, an sTREM-1 level of more than 285 pg/ml and a PCT level of more than 2.0 ng/ml in FNA fluid were independent predictors of infected necrosis. CONCLUSIONS: The fluid level of sTREM-1 will help in the rapid and accurate diagnosis of secondary infection of necrotic tissue in patients with severe acute pancreatitis (SAP).

Comparison of antioxidative and antifibrotic effects of α-tocopherol with those of tocotrienol-rich fraction in a rat model of chronic pancreatitis.

OBJECTIVES: The α-tocopherol and tocotrienol-rich fraction (TRF) are considered effective antioxidants. This study aimed to compare the antioxidative and antifibrotic effects of α-tocopherol and TFR in dibutylin dichloride (DBTC)-induced chronic pancreatitis (CP) rats. METHODS: Oral administration of α-tocopherol and TFR (both 800 mg/kg per day) started the next day after DBTC (8 mg/kg) infusion into the tail vein for 4 weeks. Histological examination, Sirius red staining, and measurement of the contents of hydroxyproline and malondialdehyde of the pancreas were performed to evaluate pancreatic damage and fibrosis. Immunohistochemical analysis of α-smooth muscle actin and real-time reverse transcription polymerase chain reaction for transforming growth factor-ß1 (TGF-ß1) and collagen-α1(I) were performed to evaluate the activation of pancreatic stellate cells and the mRNA levels of fibrosis-related genes, respectively. RESULTS: Both α-tocopherol and TRF reduced oxidative stress, ameliorated inflammation and fibrosis, and down-regulated the mRNA expression of TGF-ß1 and collagen-α1(I) in DBTC-induced CP. The TRF was superior to α-tocopherol in alleviating inflammation and fibrosis and down-regulating TGF-ß1 mRNA expression. CONCLUSIONS: Oral administration of α-tocopherol and TRF improves pancreatic inflammation and fibrosis in DBTC-induced CP rats, with TRF being more effective than α-tocopherol. Therefore, TRF may be a novel option for alleviating inflammation and, particularly, the fibrotic process in CP.

Detection of KRAS gene mutations in endoscopic ultrasound-guided fine-needle aspiration biopsy for improving pancreatic cancer diagnosis.

OBJECTIVES: Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) is a useful tool in the diagnosis of pancreatic masses. Genetic analysis of these samples could increase the sensitivity and specificity of diagnosis. This study aimed to evaluate the usefulness of a novel method for the detection of mutations in the KRAS (Kirsten rat sarcoma-2 virus) gene for the diagnosis of pancreatic cancer. METHODS: EUS-FNABs were performed on 82 patients with pancreatic masses, including 54 cases of pancreatic ductal adenocarcinoma and 28 of non-malignant pancreatic masses. The biopsies were histopathologically and cytopathologically evaluated, and the detection of KRAS gene mutations (codons 12 and 13) was performed through peptide nucleic acid-directed polymerase chain reaction clamping and DNA sequencing. RESULTS: In the pancreatic cancer cases, 88.9% (48/54; 95% confidence interval (CI): 80.5-97.2%) had KRAS mutations, while 61.1% (33/54; 95% CI: 48.1-74.1%) were unequivocally diagnosed by histo/cytopathology. In the indeterminate patients (n=49; diagnosed by EUS-FNA as either insufficient material to make a diagnosis, no malignancy, or suspicion of malignancy), there were 10 cases of pancreatic cancer with low serum carbohydrate antigen 19-9 (CA19-9) (<37 U/l) and 6 of these were KRAS mutations. The sensitivity of detection by KRAS mutations (76.2%) and the combination of KRAS mutations and serum CA19-9 (81%) were significantly higher than for serum CA19-9 alone (52.4%). A logistic regression model showed that the KRAS mutation was significant (odds ratio=5.830; CI: 1.531-22.199, P=0.01), but not serum CA19-9. In the non-malignant pancreatic masses (n=28), KRAS mutations were detected in nine precancerous lesions. CONCLUSIONS: Our method for the detection of KRAS gene mutations may be useful to supplement histo/cytopathologic evaluations for pancreatic cancer, and is superior to serum CA19-9 in EUS-FNAB histo/cytopathology-indeterminate patients. Results warrant further verification in other patient populations.

Continuous and low-energy 125I seed irradiation changes DNA methyltransferases expression patterns and inhibits pancreatic cancer tumor growth.

BACKGROUND: Iodine 125 (125I) seed irradiation is an effective treatment for unresectable pancreatic cancers. However, the radiobiological mechanisms underlying brachytherapy remain unclear. Therefore, we investigated the influence of continuous and low-energy 125I irradiation on apoptosis, expression of DNA methyltransferases (DNMTs) and cell growth in pancreatic cancers. MATERIALS AND METHODS: For in vitro 125I seed irradiation, SW-1990 cells were divided into three groups: control (0 Gy), 2 Gy, and 4 Gy. To create an animal model of pancreatic cancer, the SW 1990 cells were surgically implanted into the mouse pancreas. At 10 d post-implantation, the 30 mice with pancreatic cancer underwent 125I seed implantation and were separated into three groups: 0 Gy, 2 Gy, and 4 Gy group. At 48 or 72 h after irradiation, apoptosis was detected by flow cytometry; changes in DNMTs mRNA and protein expression were assessed by real-time PCR and western blotting analysis, respectively. At 28 d after 125I seed implantation, in vivo apoptosis was evaluated with TUNEL staining, while DNMTs protein expression was detected with immunohistochemical staining. The tumor volume was measured 0 and 28 d after 125I seed implantation. RESULTS: 125I seed irradiation induced significant apoptosis, especially at 4 Gy. DNMT1 and DNMT3b mRNA and protein expression were substantially higher in the 2 Gy group than in the control group. Conversely, the 4 Gy cell group exhibited significantly decreased DNMT3b mRNA and protein expression relative to the control group. There were substantially more TUNEL positive in the 125I seed implantation treatment group than in the control group, especially at 4 Gy. The 4 Gy seed implantation group showed weaker staining for DNMT1 and DNMT3b protein relative to the control group. Consequently, 125I seed implantation inhibited cancer growth and reduced cancer volume. CONCLUSION: 125I seed implantation kills pancreatic cancer cells, especially at 4 Gy. 125I-induced apoptosis and changes in DNMT1 and DNMT3b expression suggest potential mechanisms underlying effective brachytherapy.

Helicobacter pylori infection and gastritis: the Systematic Investigation of gastrointestinaL diseases in China (SILC).

BACKGROUND AND AIM: Helicobacter pylori infection remains common in East Asia, though its prevalence is decreasing in Western countries. H. pylori-related atrophic gastritis (AG) may reduce the likelihood of gastroesophageal reflux disease (GERD). We investigated the prevalence of H. pylori infection and AG and their association with endoscopic findings and symptom-defined GERD in Shanghai. METHODS: A representative random sample of 3600 Shanghai residents aged 18-80 years was invited to complete a general information questionnaire and a Chinese version of the Reflux Disease Questionnaire, to provide blood samples for H. pylori serology and pepsinogen (PG) I/II assay (to detect AG, defined as PGI < 70 µg/L and/or PGI/PGII < 7), and to undergo endoscopy. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by multivariate logistic regression. RESULTS: A total of 1022 Shanghai residents underwent endoscopy and were valid for inclusion in the study. Of these, 71.7% tested positive for H. pylori, 63.8% had AG and 30.5% had moderate/severe AG (PGI < 50 µg/L and/or PGI/PGII < 5). Helicobacter pylori infection was equally common in all age groups. Severity of AG increased with age in women. Reflux esophagitis was inversely associated with AG (OR, 0.23 [CI, 0.09-0.55] for moderate/severe AG compared with no H. pylori or gastritis). However, symptom-defined GERD showed no clear association with AG. CONCLUSIONS: Helicobacter pylori infection and AG are very common in Shanghai, and the infection is acquired early in life. Atrophic gastritis is inversely associated with reflux esophagitis but is not significantly associated with symptom-defined GERD.