Gut microbiota in patients after surgical treatment for colorectal cancer

Colorectal cancer (CRC) is a common disease worldwide that is strongly associated with the gut microbiota. However, little is known regarding the gut microbiota after surgical treatment. 16S rRNA gene sequencing was used to evaluate differences in gut microbiota among colorectal adenoma patients, CRC patients, CRC postoperative patients and healthy controls by comparing gut microbiota diversity, overall composition and taxonomic signature abundance. The gut microbiota of CRC patients, adenoma patients and healthy controls developed in accordance with the adenoma-carcinoma sequence, with impressive shifts in the gut microbiota before or during the development of CRC. The gut microbiota of postoperative patients and CRC patients differed significantly. Subdividing CRC postoperative patients according to the presence or absence of newly developed adenoma which based on the colonoscopy findings revealed that the gut microbiota of newly developed adenoma patients differed significantly from that of clean intestine patients and was more similar to the gut microbiota of carcinoma patients than to the gut microbiota of healthy controls. The alterations of the gut microbiota between the two groups of postoperative patients corresponded to CRC prognosis. More importantly, we used the different gut microbiota as biomarkers to distinguish postoperative patients with or without newly developed adenoma, achieving an AUC value of 0.72. These insights on the changes in the gut microbiota of CRC patients after surgical treatment may allow the use of the microbiota as non-invasive biomarkers for the diagnosis of newly developed adenomas and to help prevent cancer recurrence in postoperative patients.     

细毛樟愈伤组织培养

从富含香叶醇的细毛樟（ＣｉｎｎａｍｏｍｕｍｔｅｎｕｉｐｉｌｕｍＫｏｓｔｅｒｍ）叶片外植体诱导出愈伤组织。愈伤组织生长较合适的培养基为ｐＨ５．８附加ＩＡＡ２ｍｇ／Ｌ和ＫＴ０１ｍｇ／Ｌ的ＭＳ培养基,在２５℃下暗培养。愈伤组织无性系继代培养到第６代后芳香成分初步分析结果表明主成分仍为香叶醇。     

毛叶丁香罗勒精油的化学成分分析

西双版纳引种栽培的毛叶丁香罗勒精油用Finnigan-4510型毛细管色谱/质谱/计算机联用方法进行了化学成分分析,共分离了26个成分,鉴定了其中的16个成分,占全精油含量的98.5％。主要成分是:丁香酚(80.33％);罗勒烯(12.80％);β-毕橙茄烯(4.24％)。     

关于“狭叶桂”植物学名的商榷

关于‘狭叶桂’植物学名的商榷李锡文程必强（中国科学院昆明植物研究所,昆明６５０２０４）ＡＤＩＳＣＵＳＳＩＯＮＡＢＯＵＴＴＨＥＢＯＴＡＮＩＣＡＬＮＡＭＥＯＦ‘ＸＩＡ－ＹＥ－ＧＵＩ’ＬｉＸｉｗｅｎ,ＣｈｅｎｇＢｉｑｉａｎｇ（ＫｕｎｍｉｎｇＩｎｓｔｉｔｕｔ...     

The Combination of RAD001 and MK-2206 Exerts Synergistic Cytotoxic Effects against PTEN Mutant Gastric Cancer Cells: Involvement of MAPK-Dependent Autophagic,but Not Apoptotic Cell Death Pathway

In the current study, we showed that the combination of mammalian target of rapamycin (mTOR) inhibitor RAD001 (everolimus) and Akt inhibitor MK-2206 exerted synergistic cytotoxic effects against low-phosphatase and tensin homolog (PTEN) gastric cancer cells (HGC-27 and SNU-601 lines). In HGC-27 cells, RAD001 and MK-2206 synergistically induced G1/S cell cycle arrest, growth inhibition, cell death but not apoptosis. RAD001 and MK-2206 synergistically induced light chain 3B (LC3B) and beclin-1 expression, two important autophagy indicators. Meanwhile, the autophagy inhibitor 3-methyladenine (3-MA) and chloroquine inhibited the cytotoxic effects by RAD001 and MK-2206, suggesting that autophagic, but not apoptotic cell death was important for the cytotoxic effects by the co-administration. We observed that the combination of RAD001 and MK-2206 exerted enhanced effects on Akt/mTOR inhibition, cyclin D1 down-regulation and ERK/MAPK(extracellular signal-regulated kinase/mitogen-activated protein kinases) activation. Intriguingly, MEK/ERK inhibitors PD98059 and U0126 suppressed RAD001 plus MK-2206-induced beclin-1 expression, autophagy induction and cytotoxicity in HGC-27 cells. In conclusion, these results suggested that the synergistic anti-gastric cancer cells ability by RAD001 and MK-2206 involves ERK-dependent autophagic cell death pathway.     

Lipase-catalyzed synthesis of aliphatic polyesters and properties characterization

A novel lipase-catalyzed synthesis of aliphatic polyesters has been achieved successfully by using Candida sp.99-125 with diethyl sebacate and 1,4-butanediol as starting substrates in absence of organic solvents. The lipase from Candida sp.99-125 was employed for the first time to catalyze synthesis of poly(butylene sebacate) and showed high catalytic activity for bulkpolymerization under mild reaction conditions. The eco-friendly processes, without any environmental pollution, avoided both phase separation of the reactants and the use of toxic solvents effectively. The polycondensation reactions were performed in two stages: first stage reaction under atmospheric pressure to convert the monomers to oligomers followed by second stage reaction under vacuum process, with a highest molecular weight of 15,800 obtained in molar ratio of 1:1 at 70 °C. The corresponding polyesters determined by thermogravimetric analysis (TGA) were much thermally stable up to 300 °C. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXS) analysis demonstrated the polymers had a strong ability to crystallize with the degree of crystallinity up to 66%.     

Isolation and identification of an endophytic fungus Pezicula sp. in Forsythia viridissima and its secondary metabolites

In a survey of endophytic fungal biodiversity, an antimicrobial endophytic isolate zjwcf069 was obtained from twigs of Forsythia viridissima, Zhejiang Province, Southeast China. Zjwcf069 was then identified as Pezicula sp. through combination of morphological and phylogenetic analysis based on ITS-rDNA. Zjwcf069 here represented the first endophytic fungus in Pezicula isolated from host F. viridissima. From the fermentation broth, four compounds were obtained through silica gel column chromatography and Sephadex LH-20 under the guide of bioassay. Their structures were elucidated by spectroscopic analysis as mellein (1), ramulosin (2), butanedioic acid (3), and 4-methoxy-1(3H)-isobenzofuranone (4). Compound 4 here stood for the very first time as natural product from microbes. In vitro antifungal assay showed that compound 1 displayed growth inhibition against 9 plant pathogenic fungi, especially Botrytis cinerea and Fulvia fulva with EC₅₀ values below 50 μg/mL. Endophytic fungi in medicinal plants were good resources for bioactive secondary metabolites.     

Simultaneous acetone–butanol–ethanol fermentation,gas stripping,and full-cell-catalyzed esterification for effective production of butyl oleate

Bioprocess and Biosystems Engineering - In this study, aiming to improve the economic feasibility of acetone–butanol–ethanol (ABE) fermentation process, generate valuable products and...     

Structures of ionic liquids dictate the conversion and selectivity of enzymatic glycerolysis: theoretical characterization by COSMO-RS

Lipase-catalyzed glycerolysis of triolein has been examined using a group of tetraammonium-based ionic liquids (ILs) as media, specifically with functional groups in cation part. The results demonstrated that the reaction evolution and profile specificity of respective IL system could be quantitatively associated with the structural characteristics of the IL by means of quantum chemical and COSMO-RS calculation. Misfit interaction, Van der Waals interaction and chemical potential, etc. derived from COSMO-RS calculation are shown to be effective measures to delineate multiple interactions of ILs and then can be used to understand the effects of ILs on reactions. The hydrophobic substituents in the cation are found to contribute to the increase of triolein solubility and enhancement of initial reaction rate; while strong polar anion and polyethoxyl and free hydroxyl groups in the cation part dictate improved product selectivity through reducing activity coefficients of monoglycerides. Integration of these structures into the same molecule constitutes a promising group of ILs that could produce over 90% monoglyceride with almost 100% triglyceride conversion, as well as bulky productivity, of particular potential for industrial applications. Overall, this work has presented a first attempt to characterize the IL structure-dependency of reaction specificity by associating structural variations of ILs with thermodynamic property changes of resided compounds and subsequent effects on reaction specificity. This might be of general value to help to understand the multiple solvation interaction among IL reaction systems at molecular level and promote the application of IL-mediated reactions to practical interests.     

鸡肝散的引种和精油成分初步分析

鸡肝散(Elsholtzia blanda)种子在低温9℃左右,密藏24个月以上,种子发芽率仍可保持87％。种子从发芽生长至枯黄止,整个生育期为8—9个月。栽培植株精油含量随着生长发育日趋成熟而逐渐增加,为0.42—0.88％,主要成分芳樟醇、1,8-桉油素、苯乙酮、反-氧化芳樟醇、樟脑、龙脑等的含量,有一定的变化规律,其它成分含量变化差异较小。