Systematic investigation of stereochemistry, stereoselective bioactivity, and antifungal mechanism of chiral triazole fungicide metconazole.

In this study, the stereochemistry, stereoselective fungicidal bioactivity, and antifungal mechanism of chiral triazole fungicide metconazole were investigated. The configurations of metconazole stereoisomers were determined to be (1R, 5R)-metconazole, (1R, 5S)-metconazole, (1S, 5S)-metconazole, and (1S, 5R)-metconazole through using electronic circular dichroism spectroscopy. The bioactivities of four stereoisomers and their stereoisomer mixture toward Fusarium graminearum Schw and Alternaria triticina were found to be in the following order: (1S, 5R)-metconazole > the stereoisomer mixture > (1S, 5S)-metconazole > (1R, 5R)-metconazole > (1R, 5S)-metconazole. In addition, the fungicidal activities of (1S, 5R)-metconazole against two tested pathogens was 13.9-23.4 times higher than those of (1R, 5S)-metconazole. Molecular docking methodology was applied to characterize the docking energy and distances between Cytochrome P450 CYP51B and the metconazole stereoisomers, and (1S, 5R)-metconazole showed the strongest binding energy and the shortest distance binding to CYP51B than the other three stereoisomers. Moreover, enantioselective metabolisms of (1S, 5R)-metconazole and (1R, 5S)-metconazole by Fusarium graminearum Schw were investigated through NMR-based metabolomics. The amounts of alanine, arginine, acetate, ethanol, and dimethylamine produced in the presence of (1R, 5S)-metconazole were significantly higher than corresponding amounts in the presence of (1S, 5R)-metconazole, whereas the amounts of glucose, glycerol, glutamate, methionine, and trimethylamine formed in the presence of (1R, 5S)-metconazole were much less than those in the presence of (1S, 5R)-metconazole. This systematic investigation of metconazole stereoisomers would provide a new perception of metconazole in stereoisomeric level, including bioactivities, metabolic behaviors and antifungal mechanism.

Dehydrocostus lactone inhibits in vitro gastrinoma cancer cell growth through apoptosis induction, sub-G1 cell cycle arrest, DNA damage and loss of mitochondrial membrane potential.

INTRODUCTION: The purpose of the present study was to evaluate the antiproliferative activity of dehydrocostus lactone against human BON-1 cancer cell lines and to explore the possible underlying mechanism. MATERIAL AND METHODS: MTT cell viability assay was used to determine cytotoxic effects of dehydrocostus lactone in BON-1 cells. Fluorescence and transmission electron microscopic (TEM) techniques were used to study the effect of the compound on cellular morphology and apoptosis. Flow cytometry was used to assess the effect on cell cycle phase distribution. Effects of the drug on cell apoptosis and mitochondrial membrane potential were analyzed by flow cytometry using annexin v and rhodamine-123 as fluorescent probes. RESULTS: The results of the present study indicated that dehydrocostus lactone significantly (p < 0.01) inhibited the growth of BON-1 cancer cells. These growth inhibitory effects of dehydrocostus lactone on BON-1 were found to be time and concentration-dependent. The IC50 of dehydrocostus lactone were found to be 71.9 µM and 52.3 µM at 24 and 48 h time intervals respectively. The growth inhibitory effects of dehydrocostus lactone were found to be due to loss of mitochondrial membrane potential, the induction of apoptosis and sub-G1 cell cycle arrest. CONCLUSIONS: Dehydrocostus inhibits in vitro gastrinoma cancer cell growth and therefore may prove beneficial in the management of gastrinoma cancer.

Shock wave in a one-dimensional granular chain under Hertz contact.

The shock wave in one-dimensional bead chain is studied numerically. When the shock wave arrives, the bead velocity oscillates around the piston velocity. It is found that the shock front is composed of several solitary waves and the limitation of the maximum bead velocity is 2 times the piston velocity in the limiting case where the initial overlap is zero. If the initial overlap is not zero, then the maximum bead velocity is less than 2 times the piston velocity but larger than the piston velocity. As the initial overlap increases from zero to the finite value, the shock velocity depends on not only the piston velocity but also the initial overlap. The crossover of the dependence of the shock velocity on the piston velocity from the zero initial prestress to the finite value is obtained in the present manuscript. It is an improvement of the results presented in Phys. Rev. Lett. 108, 058001 (2012)10.1103/PhysRevLett.108.058001. In other words, the dependence of the shock velocity on the parameters of the granular materials is given.

[Preparation of δ-Valerolactone and Its Spectral Analysis].

In the study, CuO/ZnO/Al2O3 was prepared by sol-gel method. Its catalytic activity was evaluated by gas-phase catalytic dehydrogenation of 1, 5-Pentanediol to δ-valerolactone as a probe reaction. CuO/ZnO/Al2O3 and long period reactive CuO/ZnO/Al2O3 were detected by XRD. Micro-structure and essence disciplinarian of CuO/ZnO/Al2O3 were disclosed. Metal ions had a cooperative effects during the catalytic dehydrogenation of 1, 5-pentanediol to δ-valerolactone. After CuO/ZnO/Al2O3 deactivation, crystal particle size was increased clearly. It were found that characteristic diffraction peaks were caused by the catalyst temperature raising in methanol catalytic synthesis of ZnO. 1, 5-Pentanediol and δ-valerolactone were detected by FTIR. Their internal chemical bond and molecular structure were disclosed. The purity of δ-valerolactone product was very high. δ-Valerolactone and its polymer were detected by DSC. δ-Valerolactone possessed with poor stability. Polymerization reaction was easily happened by itself. So it was worth focusing on how to improve the stability of the δ-valerolactone monomer. This study could provide basic data and experimental basis for gas-phase catalytic dehydrogenation of 1, 5-Pentanediol to δ-valerolactone in pilot and industrial scale up research.

Preparation and chiral separation of a novel immobilized cellulose-based chiral stationary phase in high-performance liquid chromatography.

The chiral selector 6-azido-2, 3-di(p-chlorophenylcarbamoylated) cellulose was synthesized and further chemically immobilized onto 5-µm amino functionalized spherical porous silica gel. It was used as chiral stationary phase in high-performance liquid chromatography. Thirty racemates were successfully separated into enantiomers in either normal phase mode or reversed-phase mode. Good reproducibility and stability of the chiral stationary phase have been demonstrated.

The impact of silica gel pore and particle sizes on HPLC column efficiency and resolution for an immobilized, cyclodextrin-based, chiral stationary phase.

In this study, the CD derivative, mono (6(A)-azido-6(A)-deoxy)-per(p-chlorophenylcarbamonylated) ß-CD was chemically immobilized onto the surface of an amino-functionalized silica gel with different pore (100, 300, and 500Å) and particle (3, 5, and 10 µm) sizes to obtain novel chiral stationary phases. The impact of pore and particle size on the amount of immobilized Ph-ß-CD, column performance, and enantioselectivity was investigated by evaluating the separation of a variety of racemates in both the normal- and the reversed-phase modes. Experimental results revealed that the retention factor and resolution of racemates generally decreased with increasing pore size; the column prepared with the smallest (3 µm) silica gel particle size gave the best column performance and enantioselectivity in both the normal- and the reversed-phase modes.

[Analysis of the therapeutic effect of esophagectomy with extended 2-field lymph node dissection for esophageal carcinoma].

OBJECTIVE: To summarize the surgical effect and clinical application value of esophagectomy with extended 2-field lymph node dissection for patients with esophageal carcinoma. METHODS: From June 1987 to December 2008, 1690 patients with esophageal cancer underwent esophagectomy with extended 2-field (thoracic and abdominal) dissection of lymph nodes. Patients with the middle and lower thoracic esophageal cancer underwent Ivor-Lewis esophagectomy, and patients with upper thoracic esophageal cancer underwent Akiyama esophagectomy. 2-field (thoracic and abdominal) lymph node metastases information and the 1, 3, 5, 10-year survival rates were analyzed retrospectively. RESULTS: Lymph node metastases were found in 713 patients. The lymph node metastases rate was 42.2% (713/1690).Thoracic lymph node metastasis rate was 39.3% (665/1690), among which in the right pleural apical para-tracheal triangle was 20.7% (349/1690), in the posterior upper mediastinum was 26.3% (444/1690), in the lower mediastinum was 18.2% (307/1690). Abdominal lymph node metastasis rate was 20.1% (339/1690). THE Postoperative complication rate was 16.4% (278/1690), among which the pulmonary complication rate ranking the first, was 43.6% (136/312). The operative mortality rate was 0.2%. The 1-year, 3-year, 5-year and 10-year survival rates were 88.2% (1388/1574), 63.5% (868/1367), 54.8% (705/1287) and 30.8% (232/754), respectively. The 5-year survival rate in patients without lymph node metastasis was 76.2% (448/588), but that in patients with lymph node metastases was 36.8% (257/669). CONCLUSION: The results of this study demonstrated that Ivor-Lewis and Akiyama esophagectomy with two-field lymph node dissection exposes the operation fields clearly and make radical lymphadenectomy thoroughly, especially the lymph nodes in the posterior upper mediastinum around the recurrent laryngeal nerve and in the right pleural apical para-tracheal triangle. It is essential that patients with esophageal carcinoma with lymph node metastases should undergo esophagectomy with extended 2-field dissection of lymph nodes. This can elevate the postoperative 5-year survival rate remarkably.

Preparation and enantioseparation characteristics of a novel chiral stationary phase based on mono (6(A)-azido-6(A)-deoxy)-per(p-chlorophenylcarbamoylated) beta-cyclodextrin.

A novel cyclodextrin (CD) derivative-mono (6(A)-azido-6(A)-deoxy)-per(p-chlorophenylcarbamoylated) beta-CD was synthesized and chemically immobilized onto the surface of amino-functionalized silica gel to afford a structurally well-defined chiral stationary phase (CSP) for high performance liquid chromatography (HPLC). The p-chlorophenyl groups introduced on the beta-CD are pi-electron deficient (i.e., pi-acidic moieties); therefore the stronger pi-pi interaction which plays an important role in chiral recognition process is expected between aromatic analytes and this type of the CSP. The enantiomeric separations of 11 piperazine derivatives as well as six racemates have been successfully achieved on this CSP in the normal and reversed phase modes.

[Regulations and lymphadenectomy strategy of mediastinal and upper abdominal lymph node metastasis in thoracic esophageal carcinoma].

BACKGROUND & OBJECTIVE: Regional lymph node metastasis plays an important role in the prognosis of esophageal carcinoma. However, the range of lymph node dissection is still controversial. This study was to investigate the regulations of lymph node metastasis of thoracic esophageal carcinoma in the mediastinum and upper abdomen, and explore the rational lymphadenectomy with Ivor-Lewis procedure. METHODS: A total of 1 412 thoracic esophageal carcinoma patients underwent radical esophagectomy and mediastinal and abdominal lymphadenectomy by Ivor-Lewis procedure from 1990 to 2005 at Yangzhong People's Hospital; 517 of them underwent right para-trachea triangle field lymphadenectomy through the right pleural apical approach. The regulations of regional lymph node metastasis were analyzed. RESULTS: Of the 1,412 patients, 323 (22.88%) had postoperative complications, 2 (0.14%) died during hospitalization, and 547 (38.74%) had lymph node metastasis. The lymph node metastasis rates were 32.30% in the right para-trachea triangle, 18.43% in the upper mediastinum, 5.31% in the lower mediastinum, and 17.28% in the upper abdomen(P<0.001). Of the 13 916 resected lymph nodes, 2 662 (19.13%) were positive; the metastasis degree (positive lymph nodes/resected lymph modes) were 23.83% in the right para-trachea triangle, 18.92% in the upper mediastinum, 21.07% in the lower mediastinum, and 17.20% in the upper abdomen. For those patients with the cancer focuses in the upper, middle and lower segments of the esophagus, the lymph node metastasis rates were 40.59%, 36.97% and 44.35% (P=0.093), respectively, while the lymph node metastasis degree in these 3 fields were 19.60%, 18.35%, and 21.82%, respectively. Both the lymph node metastasis rate and degree were significantly higher in the patients at advanced stage than in the patients at early stage (46.56% vs. 7.75%, 21.82% vs. 4.01%, P<0.001). CONCLUSIONS: Regional lymph node metastasis, especially in the right para-trachea triangle and upper mediastinum, is a key factor for thoracic esophageal carcinoma. Ivor-Lewis esophagectomy with two-field lymph node dissection is a safe operation for thoracic esophageal carcinoma, and may increase the chances of complete resection.

[Right para-tracheal triangle lymphadenectomy for esophageal carcinoma].

OBJECTIVE: To investigate the incidence of lymph node metastasis (LNM) in the right para-tracheal triangle (RPT) of esophageal carcinoma patients and the technique of dissection. METHODS: On the top of double mediastinal and abdominal lymphadenectomy, 333 esophageal carcinoma patients received RPT lymphadenectomy through the right pleural apical approach from 1990 to 2001. RESULTS: In these 333 patients, the lymph node metastasis (LNM) rate in the RPT was 36.40%. A total of 457 nodes among 2 159 nodes removed gave a metastasis degree of 24.96%. The LNM rates in RPT for cervical, upper third, middle third, and lower third segments of esophagus were 66.67%, 45.45%, 34.19% and 15.79% (P < 0.05), while their respective metastasis degrees were 44.44%, 27.04%, 24.32% and 18.92% (P > 0.05). The frequency of positive nodes in the RPT for PTI, PT1, PT2, PT3 and PT4 was 0, 17.24%, 28.7%, 45.16% and 53.57%, while those of metastasis degree were 0, 8.77%, 17.62%, 33% and 41.17% (P < 0.01). The frequency of LNM in the RPT in papillary, erosive, patch-like and covert type of early tumor was 40%, 3.85%, 0 and 0 (P < 0.05), while those of the metastasis degree were 29.41%, 1.82%, 0 and 0 (P < 0.01). Higher rate of LNM in progressive stenotic esophageal carcinoma was observed compared with those of the other gross types (56.52%, P < 0.05), so was the degree (P < 0.01). The frequency of LNM in the RPT for mono-focal and multi-focal tumor was 34.98% and 70% without significant difference (P > 0.05), while the degree was 24.29% and 53.33% (P < 0.05). Postoperative complications were: leak (0.6%), and recurrent laryngeal nerve injury (1.2%). No injury of vein or infra-clavicular artery, tracheal damage or mortality occurred. CONCLUSION: 1. The lymph node metastasis from esophageal carcinoma has a tendency of wide spread and right para-tracheal triangle is an important region to be doomed. 2. With location, depth of tumor invasion and differentiation of tumor as major factors affecting LNM of esophageal carcinoma, dissection of this region should be paid more emphasis. 3. In early lesions, higher frequency of LNM in the RPT is found in papillary and erosive lesions than in the other macroscopic types. 4. Exposing the RPT, lymph node by dissection through a right pleural apical approach is very important and significant.