Versatile Cascade Esterification Route to MQ Resins.

We describe a versatile cascade route for manufacturing MQ resins using alkoxysilanes (e.g., tetraethoxysilane (TEOS)) or equivalent oligomers (e.g., ethyl polysilicate (polyTEOS)), a carboxylic acid (typically acetic acid), and hexamethyldisiloxane (MM) as starting materials; a strong acid catalyst is also employed in the one-pot reaction. The siloxane resin synthesis is accompanied by esterification of the carboxylic acid to give ethyl acetate, which acts as an important solvent, making the process more controllable. Contrary to traditional sol-gel methods, no water is introduced in the experiments, but is generated in situ. The strategy offers several advantages, including reproducibility, high yields of siloxane resins with excellent batch-to-batch consistency and without gel formation, narrow dispersity, low Si-hydroxyl residues in the final products, and the ability of increasing the molecular weight by thermal treatment. The process utilizes the green chemistry concepts of lower pollutant formation and higher atom efficiency.

Decrease of miR-622 expression promoted the proliferation, migration and invasion of cholangiocarcinoma cells by targeting regulation of c-Myc.

OBJECTIVE: To explore the mechanism of miR-622 in regulating the proliferation, migration and invasion of cholangiocarcinoma (CCA) cells. MATERIALS AND METHODS: Quantitative real-time PCR was conducted to measure the expression of miR-622 and c-Myc in CCA tissues and cell lines. Protein level of c-Myc was measured by Western blot. The effect of miR-622 on cell proliferation, migration and invasion was analyzed by MTT assay and Transwell chamber migration assay. Luciferase reporter assay was performed to measure the effect of miR-622 on c-Myc. RESULTS: miR-622 expression was downregulated in both CCA tissues and cell lines, while c-Myc expression was uregulated. Overexpression of miR-622 in CCA cells was statistically correlated with a decrease of cell proliferation, migration and invasion, while inhibition of miR-622 made an inverse result. We also proved c-Myc was identified as a target gene of miR-622 in CCA. Moreover, we found overexpression of c-Myc can strengthen the effects of miR-622 on the proliferation, migration and invasion of CCA cells. CONCLUSION: Decrease of miR-622 promotes the proliferation, migration and invasion of CCA cells by directly targeting c-Myc.

Low-threshold stimulated Brillouin scattering in high-Q whispering gallery mode tellurite microspheres.

We demonstrate the first observation of stimulated Brillouin scattering (SBS) in a high-Q whispering gallery mode tellurite microsphere. Tellurite glass with composition of 70TeO2-20ZnO-5Na2O-5La2O3 (molar ratio) was prepared in-house using a melt-quenching technique. Moreover, tellurite microspheres with Q in excess of 13 millions at 1550 nm were fabricated by melting tellurite microwires using a CO2 laser. By pumping the tellurite microspheres with a tunable single frequency laser, SBS is further realized with a threshold as low as 0.58 mW. At last, the beat notes between the pump and the Stokes signals were measured, which indicated the Brillouin frequency shift is at the 8.2 GHz band for our tellurite glass. Our results could propel significant applications utilizing SBS by employing tellurite microspheres.

Totally laparoscopic cyst excision and Roux-en-Y hepaticojejunostomy for choledochal cyst in adults: a single-institute experience of 5 years.

PURPOSE: The present study aimed to describe the authors' experience and the intermediate-term outcome for totally laparoscopic choledochal cyst excision and Roux-en-Y hepatoenterostomy at a single center in a 5-year period. METHODS: We retrospectively analyzed the clinical data of totally laparoscopic choledochal cyst excision and Roux-en-Y hepatoenterostomy on 31 adult patients from January 2009 to November 2013. RESULTS: Thirty-one cases successfully underwent totally laparoscopic choledochal cyst excision laparoscopy and Roux-en-Y hepatoenterostomy. The operation time varied from 200 to 360 minutes. The intraoperative blood loss was 50 to 210 mL. The patients passed flatus in 3.0 ± 1.3 days. The mean time interval to resume oral intake from the time of surgery was 3.8 ± 1.4 days. The duration of postoperative intravenous fluids was 4 to 11 days. Postoperative ambulation varied from 2 to 4 days. The duration of hospital stay was 4 to 13 days. Follow-up observations lasted 3 to 59 months and complications were noted in 4 patients. Of these patients, 1 patient suffered postoperative respiratory tract infection, 1 patient had an episode of adhesive small bowel obstruction, biliary leakage occurred in 1 patient, and 1 patient developed an anastomotic stoma stricture and cholangitis. There were no perioperative deaths. CONCLUSIONS: Totally laparoscopic cyst excision and Roux-en-Y hepaticojejunostomy is a safe, efficacious, and minimally invasive procedure for the most instances of adult choledochal cyst. The key of success is skilled laparoscopic skills, good team cooperation, and stapler anastomosis.

[Effect of Tip30 expression on the invasion and metastasis of hepatoma cells].

OBJECTIVE: To investigate the effect of Tip30 on the invasion and metastasis of hepatoma cells. METHODS: Recombinant plasmid pAAV-Tip30 was transfected to HepG2 cells by polylactic-coglycolic acid (PLGA) nanoparticles. RT-PCR was used to detect the mRNA expression of matrix metalloproteinases (MMP)-2, MMP-9 and epidermal growth factor receptor (EGFR). MMP- 2 and MMP-9 protein level in the tumor tissue was detected by Western blot. The proliferation, of hepatoma cells was evaluated by MTS assay and clone formation method. The adhesion and invasion of hepatoma cells were evaluated by adhesion assay and Transwell migration assay, respectively. RESULTS: With RT-PCR and Western blot, we found Tip30 decreased the expression of MMP-2 and MMP-9. MTS assay and cell clone formation method showed inhibited proliferation of the HepG2 cells. Chemo invasion assays showed that Tip30 decreased the invasiveness of hepatoma cells. Tip30 attenuated the binding of liver cancer cell line to human umbilical vein endothelial cells and fibronectin. CONCLUSION: The invasion and metastasis of hepatoma cells can be inhibited by Tip30 gene in vitro.

Factors predicting surgical resection in patients with intrahepatic cholangiocarcinoma and cirrhosis.

Here, we investigate the potential factors that affect the outcome of patients with intrahepatic cholangiocarcinomas (ICC) and cirrhosis. We retrospectively reviewed the clinical data and pathological features of 58 patients with ICC and cirrhosis who underwent liver resection between July 2000 and March 2008, and analyzed the prognostic risk factors by means of univariate and multivariate analyses. The overall morbidity and mortality were 40% and 3.3%, respectively. The overall median survival was 24 months, and the 1-, 3-, and 5-year actuarial survival rates were 53%, 18%, and 10%, respectively. Univariate analysis showed that Child-Pugh classification, hypoalbuminemia, vascular invasion, lymphnodes metastasis, tumor-nodes-metastasis (TNM) staging system, positive surgical margins, and high perioperative blood transfusion volumes were all significantly associated with poor survival. Multivariate analysis confirmed that hypoalbuminemia, vascular invasion, positive surgical margins, and high perioperative blood transfusion volume were survival related, with hazard ratios (HR) of 2.58, 3.12, 3.57, and 1.98, respectively. Surgical resection is an effective treatment for patients affected by ICC and cirrhosis. Predictive factors, including hypoalbuminemia, vascular invasion, positive surgical margins, and high perioperative blood transfusion volumes are all related to poor survival.

Major hepatectomy is a safe modality for the treatment of intrahepatic cholangiocarcinoma in selected patients complicated with cirrhosis.

OBJECTIVE: The objective of this paper is to evaluate the perioperative outcomes of major hepatectomy for intrahepatic cholangiocarcinoma (ICC) in patients with cirrhosis. METHODS: We retrospectively evaluated the preoperative, intraoperative, and postoperative findings in 42 consecutive patients with cirrhosis and in 102 patients with normal livers who underwent major hepatectomy for ICC. RESULTS: Preoperative liver function was worse in patients with cirrhosis compared to patients without cirrhosis. Cirrhotic patients had significantly higher intraoperative blood loss, longer operation time, and longer hospital stay than non-cirrhotic patients. However, the two groups had similar overall morbidity and hospital mortality rates and similar rates of liver failure or other complications. Their R0 resection rates, resection margin widths and disease-free survival rates were also similar. CONCLUSIONS: Major hepatectomy for ICC can be performed in selected cirrhotic patients with acceptable morbidity and mortality rates, as compared to patients without cirrhosis.

Prevalence of stress hyperglycemia among hepatopancreatobiliary postoperative patients.

OBJECTIVE: The aim of this study was to determine the prevalence of stress hyperglycemia and its association with mortality among hepatopancreatobiliary postoperative patients admitted. METHODS: Retrospectively analysis was made on 706 cases of the hepatopancreatobiliary postoperative patients from three Grade A hospitals in Hunan province from November 2011 to June 2012, including the incidence and risk factors of patients with stress hyperglycemia. RESULTS: The incidence of stress hyperglycemia of pancreatic postoperative patients was 34.28%. The incidence of pancreatic surgery, simple cholecystectomy and biliary tract and liver surgery in patients with stress hyperglycemia was 63.08%, 20.83% and 32.21%, respectively. Stress hyperglycemia was associated with the first postoperative glucose values, duration of surgery, whether the anemia and the presence or absence of hypoproteinemia (P<0.05), but was no related with sex, weight and previous history (P>0.05). CONCLUSION: Stress hyperglycemia is common among emergency admissions and these patients have significantly higher mortality rate compared to other patients (P=0.001). Postoperative first blood glucose levels, duration of surgery, whether the anemia and the presence or absence of hypoproteinemia were stress hyperglycemia risk factors for patients.

Differential expression of fascin, E-cadherin and vimentin: Proteins associated with survival of cholangiocarcinoma patients.

INTRODUCTION: This study investigated the differential expression of fascin, E-cadherin and vimentin in human carcinogenesis. METHODS: This study detected their expressions in 142 cholangiocarcinoma and 20 benign bile duct tissue specimens using immunohistochemistry. Clinicopathologic characteristics and survival data were also collected and analyzed for their association with expression of these 3 proteins. RESULTS: The data showed that both fascin and vimentin proteins were significantly overexpressed in cholangiocarcinoma, whereas E-cadherin expression was reduced in cholangiocarcinoma compared with normal tissues. Fascin protein expression was associated with tumor dedifferentiation, venous invasion and lymph node or distant metastasis. Similarly, vimentin expression was associated with tumor dedifferentiation and venous invasion, as well as hepatitis virus infection. In contrast, loss of E-cadherin expression was associated with tumor dedifferentiation (P < 0.05). Because the functions of these 3 proteins were closely related, the data showed that fascin and E-cadherin protein expression was reversely associated. However, fascin and vimentin protein expression was positively associated with cholangiocarcinoma. Cox multiple regression analysis showed that distant tumor metastasis, tumor differentiation and overexpression of fascin and vimentin proteins were all independent risk factors for prognosis (P < 0.05). CONCLUSION: The data from the current study demonstrated that overexpression of fascin and vimentin proteins could be further evaluated as biomarkers for the prediction of cholangiocarcinoma patient survival.

Polo-like kinase 1 contributes to the tumorigenicity of BEL-7402 hepatoma cells via regulation of Survivin expression.

Polo-like kinase 1 (PLK1) is required for multiple stages of mitosis and has been found to be overexpressed in many human malignancies. Previous studies by our group have revealed PLK1 overexpression as an independent prognostic factor for hepatocellular carcinoma (HCC). However, the underlying mechanisms of the tumorigenetic effects of PLK1 in HCC remain unclear. In this study, we depleted PLK1 in human hepatoma BEL-7402 cells using small interfering RNA. Flow cytometry analysis showed that PLK1 depletion resulted in a threefold increase in the G2/M population, with a resultant decrease in the G(1) population. Importantly, PLK1 depletion reduced the tumorigenicity of BEL-7402 cells in vivo, evidenced by significantly slower tumor growth following subcutaneous innoculation of tumor cells in the flanks of BALB/c nude mice. Furthermore, more apoptotic bodies associated with decreased Survivin protein expression and increased level of active caspase-3 were observed in tumor tissues of the PLK1 depletion group by TUNEL assay, Western blot and immunohistochemical analysis, respectively. Collectively, our findings imply that PLK1 depletion led to G2/M arrest, inhibition of cell proliferation and promotion of apoptosis via downregulation of Survivin expression, suggesting that PLK1 represents a new therapeutic target for HCC.

Bile duct injuries associated with laparoscopic and open cholecystectomy: sixteen-year experience.

AIM: To summarize the experience in diagnosis, management and prevention of iatrogenic bile duct injury (IBDI). METHODS: A total of 210 patients with bile duct injury occurred during cholecystectomy admitted to Hunan Provincial People's Hospital from March 1990 to March 2006 were included in this study for retrospective analysis. RESULTS: There were 59.5% (103/173) of patients with IBDI resulting from the wrong identification of the anatomy of the Calot's triangle during cholecystectomy. The diagnosis of IBDI was made on the basis of clinical features, diagnostic abdominocentesis and imaging findings. Abdominal B ultrasonography (BUS) was the most popular way for IBDI with a diagnostic rate of 84.6% (126/149). Magnetic resonance cholangiography (MRC) could reveal the site of injury, the length of injured bile duct and variation of bile duct tree with a diagnostic rate 100% (45/45). According to the site of injury, IBDI could be divided into six types. The most common type (type 3) occurred in 76.7% (161/210) of the patients and was treated with partial resection of the common hepatic duct and common bile duct. One hundred and seventy-six patients were followed up. The mean follow-up time was 3.7 (range 0.25-10) years. Good results were achieved in 87.5% (154/176) of the patients. CONCLUSION: The key to prevention of IBDI is to follow the "identifying-cutting-identifying" principle during cholecystectomy. Re-operation time and surgical procedure are decided according to the type of IBDI.

[An on-the-spot sampling and survey method for soil nutrient cycling study].

In this paper, an on-the-spot sampling and survey method for studying the soil nutrient cycling in a regional scale was discussed, with considering the principles of representation, reproducibility, randomness and timeliness. Firstly, some representative sampling areas in a definite region should be selected, based on the relevant hypsographic maps and airscapes. During the course of sampling soil and plant, a field survey related to the sampling sites should be carried out to understand the natural affecting factors on the soil nutrient cycling in a regional agro-ecosystem scale. Moreover, the farmers' basic status, crop production, and applied amount of fertilizers and their allotment should be also investigated. A case study of nutrient cycling in subtropical regions of China was carried out to approach the application of the method in the study of soil nutrient cycling in some regions.