Near infrared optically responsive Ag-Cu bimetallic 2D nanocrystals with controllable spatial structures.

The optical properties of cost-effective Ag-Cu bimetallic nanocrystals, with synergistically enhanced catalytic and biological activities, are limited within ultraviolet-visible region due to lack of morphology control. In order to overcome this constraint, two-dimensional (2D) Ag-Cu bimetallic heterostructures were designed and synthesized by a seed-mediated colloidal growth method. The conformal Cu domain was epitaxially deposited on Ag nanoplates with different spatial configuration under retention of their 2D shape. Both of the 2D Ag-Cu core@shell and Janus structures display tunable localized surface plasmon resonance from visible to near infrared regions. The results of catalytic reduction of 4-nitrophenol show that the 2D Ag-Cu core@shell structure has better synergistic catalytic performance than Janus structure and Ag plates. In addition to surface-related synergistically enhanced bactericidal performance, their antibacterial effect can also be significantly enhanced by near infrared light irradiation. These results indicate that 2D Ag-Cu heterostructures can benefit from both synergistically improved surface activity and great optical responsive characteristics.

Polysaccharide sulphated derivative from Aconitum coreanum induces cell apoptosis in the human brain glioblastoma U87MG cell line via the NF-κB/Bcl-2 cell apoptotic signaling pathway.

In a previous study, our team preliminarily investigated the bioefficacy of an extracted polysaccharide from the medicinal plant Aconitum coreanum (ACP1). In the present study, we further evaluated the antitumor efficacy of an ACP1 sulphated derivative (ACP1­s) in the human brain glioblastoma U87MG cell line. Cell viability assay and flow cytometry results demonstrated that 400, 800 and 1,600 µg/ml ACP1­s induced cell growth inhibition and cell apoptosis. We then investigated the underlying molecular mechanism of the ACP1­s induced cell apoptosis and found that the NF­κB/Bcl­2 cell apoptotic signaling pathway was involved. Following treatment with ACP1­s, the expression of IκB in U87MG cells was significantly upregulated, whereas the level of NF­κB and the ratio of Bcl­2/Bax was significantly decreased. The level of cleaved caspase­3 was increased accordingly. When we introduced exogenous p65 protein into the U87MG cells, the ACP1­s-induced cell growth inhibition and cell apoptosis were partially neutralized, and the expression of the anti­apoptotic gene Bcl­2 was recovered accordingly. These findings suggest the potential value of ACP1­s as a novel therapeutic agent for the treatment of glioblastoma.

Safety and efficacy of early radiofrequency catheter ablation in patients with paroxysmal atrial fibrillation complicated with amiodarone-induced thyrotoxicosis.

BACKGROUND: Amiodarone is an antiarrhythmic drug that is frequently used to control atrial fibrillation (AF). Many patients with AF are afraid of the risk of ablation and take amiodar-one, some patients develop amiodarone-induced thyrotoxicosis (AIT). The purpose of the study was to investigate the safety and efficacy of early radiofrequency catheter ablation in patients with paroxysmal AF complicated with AIT. METHODS: From the 146 consecutive patients with paroxysmal AF who had been treated with amiodarone and underwent 3-dimensional mapping system guided circumferential pulmonary vein isolation (PVI) at our center from January 2013 to June 2014, 20 had developed AIT. Thirty controls with normal thyroid function and matched for baseline characteristics were selected. RESULTS: Pulmonary vein isolation was completed in all patients without serious complications and with similar procedural (170.60 ± 14.80 vs. 158.18 ± 9.06 min; p = 0.062) and X-ray exposure (16.48 ± 2.15 vs. 15.36 ± 1.57 min; p = 0.058) time in AIT vs. control groups; however, upon coronary sinus catheter pacing (from 300 ms to 200 ms) after intrave-nous isoproterenol administration 30 min post PVI, rates of induction of AF (35% vs. 3.33%; p = 0.005) and of non-pulmonary vein-related atrial tachyarrhythmias (50% vs. 6.67%; p = 0.01) were higher, while those for atrial flutter (15% vs. 3.33%; p = 0.17) and atrial tachycardia (15% vs. 6.67%; p = 0.31) were similar, as was the recovery of conduction of pulmonary vein potential (15% vs. 30%; p = 0.191). In AIT vs. control group, atrial tachyarrhythmia recurrence rate was higher at 3 months (45% vs. 16.67%, p = 0.032) but not between 3 and 12 months (30% vs. 23.33%; p = 0.418) follow-up. CONCLUSIONS: Early catheter ablation for paroxysmal AF in patients with AIT appeared safe and effective albeit with higher atrial tachyarrhythmia recurrence rate up to 3 months but not beyond 12 months after PVI relative to controls.

Effect of rhizosphere enzymes on phytoremediation in PAH-contaminated soil using five plant species.

A pot experiment was performed to study the effectiveness of remediation using different plant species and the enzyme response involved in remediating PAH-contaminated soil. The study indicated that species Echinacea purpurea, Festuca arundinacea Schred, Fire Phoenix (a combined F. arundinacea), and Medicago sativa L. possess the potential for remediation in PAH-contaminated soils. The study also determined that enzymatic reactions of polyphenol oxidase (except Fire Phoenix), dehydrogenase (except Fire Phoenix), and urease (except Medicago sativa L.) were more prominent over cultivation periods of 60d and 120d than 150d. Urease activity of the tested species exhibited prominently linear negative correlations with alkali-hydrolyzable nitrogen content after the tested plants were cultivated for 150d (R2 = 0.9592). The experiment also indicated that alkaline phosphatase activity in four of the five tested species (Echinacea purpurea, Callistephus chinensis, Festuca arundinacea Schred and Fire Phoenix) was inhibited during the cultivation process (at 60d and 120d). At the same time, the study determined that the linear relationship between alkaline phosphatase activity and effective phosphorus content in plant rhizosphere soil exhibited a negative correlation after a growing period of 120d (R2 = 0.665). Phytoremediation of organic contaminants in the soil was closely related to specific characteristics of particular plant species, and the catalyzed reactions were the result of the action of multiple enzymes in the plant rhizosphere soil.

Comparison between better and poorly differentiated locally advanced gastric cancer in preoperative chemotherapy: a retrospective, comparative study at a single tertiary care institute.

BACKGROUND: Gastric cancer is the third leading cause of cancer-related mortality in China, and the long-term survival for locally advanced gastric cancer is very poor. Simple surgery cannot yield an ideal result because of the high recurrence rate after tumor resection. Preoperative chemotherapy could help to reduce tumor volume, improve the R0 resection rate (no residual tumor after surgery), and decrease the risk of local tumor recurrence. The aim of this study was to evaluate the influence of pathological differentiation in the effect of preoperative chemotherapy for patients with locally advanced gastric cancer. METHODS: Patients with locally advanced gastric cancer (n = 32) received preoperative chemotherapy under the XELOX (capecitabine plus oxaliplatin) regimen. According to pathological examination, patients' tumors were classified into better (well and moderate) and poorly differentiated (lower differentiated and undifferentiated) groups, and the clinical response rate, type of gastrectomy, and negative tumor residual rate were compared between the two groups of patients. Morphological changes and toxic reactions were monitored after chemotherapy. RESULTS: The results showed that the clinical response rate in the better differentiated group was significantly higher than that in the poorly differentiated group (100% versus 25%, P = 0.000). The partial gastrectomy rate in the better differentiated group was significantly higher than that in the poorly differentiated group (87.5% versus 25% P = 0.000). A significant shrinking of tumor and necrosis of tumor tissues caused by chemotherapy could be observed. CONCLUSIONS: In conclusion, the better differentiated group with locally advanced gastric cancer is suitable for preoperative chemotherapy under the XELOX regimen, and as a result of effective preoperative chemotherapy, much more gastric tissue can be preserved for the better differentiated group.

[Comparative metabonomics study on urine in rat treated by Angelica sinensis volatile oil].

Metabonomics was employed to investigate the effect of Angelica sinensis volatile oil (ASVO) to the endogenous metabolites of normal rats, and to reveal the possible ways of metabolism in rats caused by ASVO. The fifty male Waster rats were randomly divided into five groups (each consists of 10 rats), such as control group, high dose group of ASVO, middle dose group of ASVO, low dose group of ASVO, and Aspirin group. They were given 0.9% saline, 0.352 mL x kg(-1) ASVO, 0.176 mL x kg(-1) ASVO, 0.088 mL x kg(-1) ASVO and ASP respectively with the equal volume of 0.2 mL. Drugs and vehicle were given for 3 successive days. The urine was collected at 12, 24, 36, 48 h after modeling with metabolic cages. Rat urine metabolic fingerprint in different stages was analyzed using GC-MS, based on which the principal component analysis (PCA)and orthogonal partial least-squares discriminant analysis (OPLS-DA) models were established for metabonomic analysis. Potential biomarkers were screened by using variable importance in the projection (VIP) and T test. It was revealed that the middle dose of ASVO at 36 h induces a substantial change in rat urine. Compared with control group, seven kinds of endogenous metabolites in ASP group and ASVO group change significantly (P < 0.05), among which aconitic acid, succinic acid, citric acid, alpha-ketone glutaric acid, glycine and malic acid content had an upward trend (P < 0.05) and prostaglandin content had a downward trend (P < 0.01). The mechanism of ASVO and ASP have the similarity. It is likely that ASVO intervenes the metabolic process by affecting the energy, amino acid and lipid metabolism. Our work also indicates that rats administrated with ASVO can increase the energy metabolism of the body, induce the production of inflammatory substances and strengthen the body's immune ability. The result has also provide a proof for futher interpret ASVO pharmacological effects.