[Cu(phen)2](2+) acts as electrochemical indicator and anchor to immobilize probe DNA in electrochemical DNA biosensor.

We demonstrate a novel protocol for sensitive in situ label-free electrochemical detection of DNA hybridization based on copper complex ([Cu(phen)2](2+), where phen = 1,10-phenanthroline) and graphene (GR) modified glassy carbon electrode. Here, [Cu(phen)2](2+) acted advantageously as both the electrochemical indicator and the anchor for probe DNA immobilization via intercalative interactions between the partial double helix structure of probe DNA and the vertical aromatic groups of phen. GR provided large density of docking site for probe DNA immobilization and increased the electrical conductivity ability of the electrode. The modification procedure was monitored by electrochemical impedance spectroscopy (EIS). Square-wave voltammetry (SWV) was used to explore the hybridization events. Under the optimal conditions, the designed electrochemical DNA biosensor could effectively distinguish different mismatch degrees of complementary DNA from one-base mismatch to noncomplementary, indicating that the biosensor had high selectivity. It also exhibited a reasonable linear relationship. The oxidation peak currents of [Cu(phen)2](2+) were linear with the logarithm of the concentrations of complementary target DNA ranging from 1 × 10(-12) to 1 × 10(-6) M with a detection limit of 1.99 × 10(-13) M (signal/noise = 3). Moreover, the stability of the electrochemical DNA biosensor was also studied.

The simultaneous electrochemical detection of catechol and hydroquinone with [Cu(Sal-ß-Ala)(3,5-DMPz)2]/SWCNTs/GCE.

A glassy carbon electrode was modified with a copper(II) complex [Cu(Sal-ß-Ala) (3,5-DMPz)2] (Sal = salicylaldehyde, ß-Ala = ß-alanine, 3,5-DMPz = 3,5-dimethylpyrazole) and single-walled carbon nanotubes (SWCNTs). The modified electrode was used to detect catechol (CT) and hydroquinone (HQ) and exhibited good electrocatalytic activities toward the oxidation of CT and HQ. The peak currents were linear with the CT and HQ concentrations over the range of 5-215 µmol·L(-1) and 5-370 µmol·L(-1) with corresponding detection limits of 3.5 µmol·L(-1) and 1.46 µmol·L(-1) (S/N = 3) respectively. Moreover, the modified electrode exhibited good sensitivity, stability and reproducibility for the determination of CT and HQ, indicating the promising applications of the modified electrode in real sample analysis.

Heterologous Expression, Purification and Characterization of an Alkalic Thermophilic ß-Mannanase CcMan5C from Coprinopsis cinerea.

A endo-1,4-ß-mannanase (CcMan5C) gene was cloned from Coprinopsis cinerea and heterologously expressed in Pichia pastoris, and the recombinant enzyme was purified by Ni-affinity chromatography and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/TOF-MS). CcMan5C hydrolyzed only locust bean gum galactomannan (LBG) but not α-mannan from S. cerevisiae or Avicel cellulose, oat spelt xylan, or laminarin from Laminaria digitata. CcMan5C exhibited distinctive catalytic features that were different from previously reported ß-mannanases. (1) CcMan5C is the first reported fungal ß-mannase with an optimal alkalic pH of 8.0-9.0 for hydrolytic activity under assay conditions. (2) CcMan5C is the first reported alkalic fungal ß-mannase with an optimal temperature of 70 °C for hydrolytic activity under assay conditions. (3) The organic solvents methanol, ethanol, isopropanol, and acetone at concentrations of 10% or 20% did not inhibit CcMan5C activity, while 10% or 20% isopropanol and acetone even enhanced CcMan5C activity by 9.20-34.98%. Furthermore, CcMan5C tolerated detergents such as Tween 20 and Triton X-100, and its activity was even enhanced to 26.2-45.6% by 1% or 10% Tween 20 and Triton X-100. (4) CcMan5C solution or lyophilized CcMan5C exhibited unchanged activity and even increasing activity after being stored at -20 °C or -80 °C for 12 months and retained above 50% activity after being stored at 4 °C for 12 months. These features make CcMan5C a suitable candidate for the detergent industry and paper and pulp industry.

An Aspergillus nidulans endo-ß-1,3-glucanase exhibited specific catalytic features and was used to prepare 3-O-ß-cellobiosyl-d-glucose and 3-O-ß-gentiobiosyl-d-glucose with high antioxidant activity from barley ß-glucan and laminarin, respectively.

An endo-ß-1,3(4)-glucanase AnENG16A from Aspergillus nidulans shows distinctive catalytic features for hydrolysis of ß-glucans. AnENG16A hydrolyzed Eisenia bicyclis laminarin to mainly generate 3-O-ß-gentiobiosyl-d-glucose and hydrolyzed barley ß-glucan to mainly produce 3-O-ß-cellobiosyl-d-glucose. Using molecular exclusion chromatography, we isolated and purified 3-O-ß-cellobiosyl-d-glucose and 3-O-ß-gentiobiosyl-d-glucose, respectively, from AnENG16A-hydrolysate of barley ß-glucan and E. bicyclis laminarin. Further study reveals that 3-O-ß-cellobiosyl-d-glucose had 8.99-fold higher antioxidant activity than barley ß-glucan and 3-O-ß-gentiobiosyl-d-glucose exhibited 43.0% higher antioxidant activity than E. bicyclis laminarin. Notably, 3-O-ß-cellobiosyl-d-glucose and 3-O-ß-gentiobiosyl-d-glucose exhibited 148.9% and 116.0% higher antioxidant activity than laminaritriose, respectively, indicating that ß-1,4-linkage or -1,6-linkage at non-reducing end of ß-glucotrioses had enhancing effect on antioxidant activity compared to ß-1,3-linkage. Furthermore, 3-O-ß-cellobiosyl-d-glucose showed 237.9% higher antioxidant activity than cellotriose, and laminarin showed 5.06-fold higher antioxidant activity than barley ß-glucan, indicating that ß-1,4-linkage at reducing end of ß-glucans or oligosaccharides resulted in decrease of antioxidant activity compared to ß-1,3-linkage.

The role of SOX2 overexpression in prognosis of patients with solid tumors: A meta-analysis and system review.

BACKGROUND: Many studies have been done to reported the value of SRY-related HMG-box Gene 2 (SOX2) in prognosis of solid tumors. But results were not particularly consistent among these studies because of the limitations of the small sample data. METHODS: We searched relevant studies published before November 2018 by PubMed, Web of Science and EMBASE. In this meta-analysis, hazard ratio (HR) values for overall survival (OS) were cumulatively pooled and quantitatively analyzed. RESULTS: A meta-analysis based on 12 studies with 3318 patients was conducted to assess the potential correlation between SOX2 overexpression and OS in human solid tumors. A total of 12 studies (n = 3318) were assessed in the meta-analysis. It suggested that the high expression of SOX2 obviously indicates poor survival and prognosis in both univariate and multivariate analysis. In the univariate analysis, the combined HR for OS was 1.66 (95% confidence interval [CI]: 1.46-1.89, P < .001). The pooled HR of multivariate analysis for OS was 1.51 (95% confidence interval [CI]: 1.32-1.71, P < .001). CONCLUSIONS: This meta-analysis indicated that the high expression level of SOX2 is significantly associated with a decline in survival of human with solid tumors. On the basis of the expression level in solid tumors, SOX2 is expected to be a meaningful prognostic biomarker and effective therapeutic target.

NOTES: new dimension of minimally invasive surgery.

Natural orifice transluminal endoscopic surgery (NOTES) is an emerging experimental alternative to conventional surgery. NOTES eliminates abdominal incisions and incision-related complications by combining endoscopic and laparoscopic techniques to diagnose and treat abdominal pathology. Since the first NOTES was reported by Kalloo et al. in 2004, significant achievements in the laboratory have occurred. Clinical use in humans has been limited, but several cases and one small clinical trial were published recently. As a further technical revolution in minimally invasive surgery, NOTES has the promising potential to be safer, less invasive, provide better cosmesis and possibly be more cost-effective. The purpose of the present article was to review the development and current status of NOTES and highlight important advances associated with this innovative approach.

[Comparing the influencing factors of anastomotic bleeding in rectal carcinoma resection between laparoscopic and open radical approaches].

OBJECTIVE: To observe the occurrence of anastomotic bleeding following laparoscopic and open radical resection for rectal carcinoma, and to explore its contributing factors. METHODS: Two hundred and sixty-three cases of rectal carcinoma undergone radical resection were divided into 2 groups, laparoscopic surgery (LS) group (n=86) and open surgery (OS) group (n=177). According to the different locations of anastomotic stoma and with or without preventive colostomy, the two groups were divided into AR sub-group and LAR/UAR sub-group, colostomy sub-group and non-colostomy sub-group. After analyzing the incidence of anastomotic bleeding in each sub-group, a logistic regression model was established to determine the relationships between anastomotic bleeding and three contributing factors including surgical approaches (LS or OS), location of stoma (AR or LAR/UAR) and preventive colostomy. RESULTS: Anastomotic bleeding occurred on 16 out of 263 patients with radical resection of rectal cancer (6.1%). The rates of anastomotic bleeding in LS group and OS group were 9.3% and 4.5%, in colostomy and non-colostomy were 8.1% and 5.5%, and in AR group and LAR/UAR group were 3.3% and 12.1% respectively, there were no significant differences between them (P>0.05). Comparing the two different surgical approaches (LS vs OS), the coefficient of regression, odd ratio and standard coefficient of regression for LS were 1.319, 3.741 and 0.342 respectively. In comparison of the locations of anastomosis (AR vs LAR/UAR), the three index for LAR/UAR were 2.460, 11.704, and 0.632 respectively. Comparing colostomy with non-colostomy, the three index for colostomy were -1.394, 0.248, and -0.327 respectively. CONCLUSIONS: Anastomotic bleeding after radical rectectomy is related to the choice of surgical approach, location of anastomosis and with or without preventive colostomy. Both LS and LAR/UAR are risk factors, and preventive colostomy is a protective factor. Regarding to the significance of three factors, location of anastomosis takes the first place, following by surgical method and with or without preventive colostomy.