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Journal of Forestry Research 2015年第4期26卷 1003-1011页

作者： Suvarna J.Shreelalitha Kandikere R.Sridhar department of biotechnology St.Aloysius College department of Biosciences Mangalore University

Evaluation of 450 surface sterilized tissue segments of a seasonal wild legume, Sesbania bispinosa （Jacq.）, of coastal sand dunes and mangroves of southwest India yielded 546 isolates comprising 39 endophytic fungi with six dominant taxa （Aspergillus flavus, Aspergillus niger, Cladosporium tenuissimum, Fusarium moniliforme, Penicillium chrysogenum and morpho sp. 1）. A consortium of saprophytic, pathogenic and toxigenic fungi exists as endophytes in S. bispinosa. Number of segments colonized, number of isolates obtained, species richness and diversity were higher in S. bispinosa in mangroves compared to coastal sand dunes. Seeds yielded more fungal isolates, but species richness and diversity were low. In spite of low fungal colonization in root segments, the diversity was high. Up to 30-40 % endophytic fungi of S. bispinosa differed between coastal sand dunes and mangroves revealing partial host- and habitat-specificity. As S. bispi- nosa is extensively used as green manure and forage in southwest India, further studies especially on the bioactive compounds of its endophytic fungi might broaden its range of uses. In addition to conventional morphologicaltechniques, molecular tools would provide precise insight on the endophytic fungi of coastal sand dunes and mangroves.

关键词： Legumes Sesbania bispinosa Endophyticfungi Coastal sand dunes Mangroves

Involvement of nitric oxide signaling in mammalian Bax-induced terpenoid indole alkaloid production of Catharanthus roseus cells

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Science China(Life Sciences) 2007年第6期50卷 799-807页

作者： XU MaoJun DONG JuFang department of biotechnology Zhejiang Gongshang University Hangzhou 310035 China Department of Biotechnology Zhejiang Gongshang University Hangzhou 310035 China

Bax, a mammalian pro-apoptotic member of the Bcl-2 family, has been demonstrated to be a potential regulatory factor for plant secondary metabolite biosynthesis recently. To investigate the molecular mechanism of Bax-induced secondary metabolite biosynthesis, we determined the contents of nitric oxide (NO) of the transgenic Catharanthus roseus cells overexpressing a mouse Bax protein and checked the effects of NO specific scavenger 2,4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1- oxyl-3-oxide (cPITO) on Bax-induced terpenoid indole alkaloid (TIA) production of the cells. The data showed that overexpression of the mouse Bax in C. roseus cells triggered NO generation of the cells. Treatment of cPITO not only inhibited the Bax-triggered NO burst but also suppressed the Bax-induced TIA production. The results indicated that the mouse Bax might activate the NO signaling in C. roseus cells and induce TIA production through the NO-dependent signal pathway in the cells. Furthermore, the activities of nitric oxide synthase (NOS) were significantly increased in the transgenic Bax cells as compared to those in the control cells, showing that the mouse Bax may induce NOS of C. roseus cells. Treatment of the transgenic Bax cells with NOS inhibitor PBITU blocked both Bax-induced NO genera- tion and TIA production, which suggested that the mouse Bax might trigger NO generation and TIA production through NOS. However, the NOS-like activities and NO generation in the transgenic Bax cells did not match kinetically and the Bax-induced NOS-like activity was much later and lower than NO production. Moreover, the Bax-induced NO generation and TIA production were only partially inhibited by PBITU. Thus, our results suggested that the Bax-induced NO production and secondary metabolite biosynthesis in C. roseus cells was not entirely dependent on NOS or NOS-like enzymes.

关键词： Bax, nitric oxide, Catharanthus roseus cells, terpenoid indole alkaloid (TIA)

Preparation of 3-D porous fibroin scaffolds by freeze drying with treatment of methanol solutions

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Chinese Science Bulletin 2007年第13期52卷 1791-1795页

作者： ZHAN JingLin SUN XiaoDan CUI FuZhai KONG XiangDong Laboratory of Advanced materials Department of Materials Science & Engineering Tsinghua University Beijing 100084 China Xinyuan Institute of Medicine and biotechnology College of Life Science Zhejiang Science and Technology University Hangzhou 310029 China

In this study, silk scaffolds with appropriate porous structures were prepared by adjusting solution concentrations and providing treatment with methanol solutions in the way of freeze drying. The effects of the preparation conditions on the microstructures and properties of the scaffolds were discussed. Fibroin solutions with different concentrations of 4, 6, 8, 10 wt% were used respectively to prepare the scaffolds. The effects of the addition of 20 vol% methanol before or after freeze drying to the 4 wt% fibroin solution were investigated. As demonstrated by Scanning Electron Microscope (SEM), the fib-roin scaffolds prepared without methanol had porous microstructures composed of thin sheets, and the sizes of the pores decreased with the increase of the fibroin solution concentrations, while the scaffolds prepared in the presence of methanol showed porous microstructures formed by fine-particle aggregates. The porosities and mechanical properties of the prepared fibroin scaffolds under different conditions were tested. The crystalline structures and conformations of the fibroin scaffolds were detected by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD).

关键词：蚕丝蛋白多孔材料冷藏干燥甲醇

Umbilical cord:an unlimited source of cells differentiable towards dopaminergic neurons

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Neural Regeneration Research 2017年第7期12卷 1186-1192页

作者： Mahdi Eskandarian Boroujeni Mossa Gardaneh department of Stem Cells and Regenerative Medicine Faculty of Medical Biotechnology National Institute of Genetic Engineering and Biotechnology Tehran Iran

Cell replacement therapy utilizing mesenchymal stem cells as its main resource holds great promise for ultimate treatment of human neurological ***＇s disease（PD）is a common,chronic neurodegenerative disorder hallmarked by localized degeneration of a specific set of dopaminergic neurons within a midbrain *** specific cell type and confined location of degenerating neurons make cell replacement therapy ideal for PD treatment since it mainly requires replenishment of lost dopaminergic neurons with fresh and functional *** as well as exogenous cell sources have been identified as candidate targets for cell replacement therapy in *** this review,umbilical cord mesenchymal stem cells（UCMSCs）are discussed as they provide an inexpensive unlimited reservoir differentiable towards functional dopaminergic neurons that potentially lead to long-lasting behavioral recovery in PD *** also present mi RNAs-mediated neuronal differentiation of *** UCMSCs bear a number of outstanding characteristics including their non-tumorigenic,low-immunogenic properties that make them ideal for cell replacement therapy ***,more investigations as well as controlled clinical trials are required to thoroughly confirm the efficacy of UCMSCs for therapeutic medical-grade applications in PD.

关键词： nerve regeneration umbilical cord mesenchymal stem cells differentiation neuronal dopaminergicneurons dopamine substantia nigra ventral mesencephalon Parkinson's disease cell replacement therapy neural regeneration

The incidence of sporadic viral hepatitis in North India:a preliminary study

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Hepatobiliary & Pancreatic Diseases International 2007年第6期6卷 596-599页

作者： Subrat Kumar Radha Kanta Ratho Yogesh Kumar Chawla Anuradha Chakraborti department of Virology department of Hepatology department of Experimental Medicine and biotechnology

BACKGROUND: Viral hepatitis is one of the major causes of mortality and morbidity in developing countries. Hepatitis E virus (HEV) among the major etiological agents is responsible for both sporadic and epidemic outbreaks. The epidemic outbreak is water-borne whereas the sporadic outbreak is possibly through contact. Various diagnostic tools at times fail to pinpoint the cause of viral hepatitis. This study was carried out to evaluate the utility of ELISA and nRT-PCR (nested reverse transcriptase polymerase chain reaction) for the diagnosis of sporadic and acute viral hepatitis (AVH) caused by HEV in an endemic situation in North India. METHODS: Serum samples were collected from all the affected and suspected persons and subjected to serological detection of HAV IgM, HBsAg, HCV antibody and HEV IgM. The samples that were positive for HEV IgM were further processed for the detection of HEV RNA by nRT-PCR. RESULTS: A total of 843 samples were collected from 685 patients with AVH, 70 patients with fulminant hepatic failure (FHF), 53 patients with chronic liver disease (CLD), 11 patients with antituberculosis therapy (ATT)-induced jaundice, and 24 pregnant women. The percentage of positivity for anti-HEV IgM was 58.3% in the pregnant women, 41.4% in the paients with FHF, 38.6% in the patients with AVH, 9.4% in the patients with CLD and 18.2% in the patients with ATT induced jaundice. 9.4% of HBsAg carriers were positive for anti-HEV IgM. Males outnumbered females (62.8% vs. 37.1%). Furthermore, the rates of fulminant and acute outbreaks of hepatitis with HEV RNA positivity were 41.4% and 9.4%, respectively. CONCLUSION: Serological and molecular analysis should be combined for the diagnosis of viral infections, especially in endemic areas.

关键词： viral hepatitis fulminant liver failure pregnancy

In vitro and in vivo degradability,biocompatibility and antimicrobial characteristics of Cu added iron-manganese alloy

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Journal of materials Science & Technology 2021年第25期84卷 159-172页

作者： Santanu Mandal Vijay Kishore Madhuparna Bose Samit Kumar Nandi Mangal Ro department of Metallurgical and materials Engineering Indian Institute of Technology-KharagpurKharagpur 721302India department of Veterinary Surgery&Radiology West Bengal University of Animal&Fishery SciencesKolkata 700037India department of biotechnology Indian Institute of TechnologyKharagpur 721302India

In recent years,iron(Fe)based degradable metal is explored as an alternative to permanent fracture fixation *** the present work,copper(Cu)is added in Fe-Mn system to enhance the degradation rate and antimicrobial ***-Mn-x Cu(x=0.9,5 and 10 wt.%)alloys are prepared by the meltingcasting-forging *** analysis confirms austenite phase stabilization due to the presence of Mn and *** predicted by Thermo-Calc calculations,Cu rich phase precipitations are noticed along the austenite grain *** behaviours of Cu added Fe-Mn alloys are investigated through static immersion and electrochemical polarization where enhanced degradation is found for higher Cu added *** challenged against *** bacteria,the Fe-Mn-Cu alloy media extract shows a significant bactericidal effect compare to the base *** vitro cytocompatibility studies,as determined using MG63 and MC3T3-E1 cell lines,indicate increased cell density as a function of time for all the *** implanted in rabbit femur,the newly developed alloy does not show any kind of tissue necrosis around the *** osteogenesis and higher new bone formation are observed with Fe-Mn-10 Cu alloy as evident from micro-computed tomography(μ-CT)and fluorochrome labelling.

关键词： Iron-manganese alloy Degradable metal In vitro Micro-CT

RECOGNITION SEQUENCE SPECIFICITY OF SIGNAL PEPTIDASE I AND THE ROLE OF SIGNAL PEPTIDE IN SECRETION OF PROTEIN IN Bacillus subtilis

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Science China Chemistry 1991年第9期34卷 1082-1091页

作者：周毅蒋如璋 Laboratory for biotechnology Department of Biology Nonkai University

By recombinant DNA technology, the N-terminal of the β-protein encoding region of plasmid pUBHO is fused with the structure gene of α-amylase from Bacillus licheniformis. This gene fusion is called βAmy. It is able to transcribe and translate in phase. Protein fusion can be secreted into the medium mediated by β-signal peptide. The efficiency of secretion is about 10% of the synthesized pre-α-amylase. By comparing the secretion capacities and analysing the restriction sites on β-Amy genes and the molecular weights of the mature α-amylase secreted by B. subtilis harbouring different plasmids, it is indicated in vivo that the recognition and cleavage sequence for signal peptidase I of B. subtilis is Ala-Ala-Ala Ala. The results also indicate that the secretion of the α-amylase in B. subtilis is in accordance with the post-translational transportation mode.

关键词： α-amylase β-Amy gene β-signal peptide signal peptid-ase Ⅰ post-translational transfer Bacillus subtilis.

Progress in artificial control system for gene expression

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Chinese Science Bulletin 2000年第10期45卷 865-870页

作者： ZHANG Yong ZHAO Nanming LIU Qiang department of Biological Science and biotechnology Tsinghua UniversityBeijing 100084China department of Biological Science and biotechnology State Laboratory of Biomembrane and Membrane BiotechnologyTsinghua UniversityBeijing 100084China

Along with the increasingly wide application of transgenic techniques, new stricter criteria have been raised for controlling the expression of exogenous genes. For these demands, a series of artificial control systems for gene expression have been developed and testified in recent years, which can control exogenous genes expression in exact time and certain level by administration of a specific drug or hormone. The successful construction of these systems offers a practicable method to control precise expression of exogenous gene in organisms, and raises the feasibility of wide application of gene therapy.

关键词： control system expression control exogenous gene.

Enhanced removal of nitrate and phosphate from wastewater by Chlorella vulgaris: Multi-objective optimization and CFD simulation

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Chinese Journal of Chemical Engineering 2019年第3期27卷 639-648页

作者： Mohammad Bagher Sabeti Mohammad Amin Hejazi Afzal Karimi Faculty of Chemical and Petroleum Engineering University of Tabriz department of Food biotechnology Branch for Northwest & West Region Agricultural Biotechnology Research Institute of Iran Agricultural Education and Extension Organization (AREEO) department of biotechnology Faculty of Advanced Technologies in Medicine Iran University of Medical Sciences

To enhance the efficiency of wastewater biotreatment with microalgae, the effects of physical parameters need to be investigated and optimized. In this regard, the individual and interactive effects of temperature, p H and aeration rate on the performance of biological removal of nitrate and phosphate by Chlorella vulgaris were studied by response surface methodology(RSM). Furthermore, a multi-objective optimization technique was applied to the response equations to simultaneously find optimal combinations of input parameters capable of removing the highest possible amount of nitrate and phosphate. The optimal calculated values were temperature of 26.3 °C, pH of 8 and aeration rate of 4.7 L·min^(-1). Interestingly, under the optimum condition, approximately 85% of total nitrate and 77% of whole phosphate were removed after 48 h and 24 h, respectively, which were in excellent agreement with the predicted values. Finally, the effect of baffle on mixing performance and, as a result, on bioremoval efficiency was investigated in Stirred Tank Photobioreactor(STP) by means of Computational Fluid Dynamics(CFD). Flow behavior indicated substantial enhancement in mixing performance when the baffle was inserted into the tank. Obtained simulation results were validated experimentally. Under the optimum condition, due to proper mixing in baffled STP, nitrate and phosphate removal increased up to 93% and 86%,respectively, compared to unbaffled one.

关键词： Nitrate Phosphate Nutrient removal Response surface methodology Stirred Tank Photobioreactor Computational Fluid Dynamics

Remediation of polycyclic aromatic hydrocarbon-contaminated soils using microbes and nanoparticles: A review

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Pedosphere 2023年第1期33卷 93-104页

作者： Ritu PANWAR Jyoti MATHUR department of Bioscience and biotechnology Banasthali VidyapithRajasthan 304022India

Polycyclic aromatic hydrocarbon(PAH)pollution is a global concern because of their toxicity to environment and ecosystem,which induces adverse effects on plants,animals,and *** are mainly released from natural and anthropogenic activities,such as incomplete fuel combustion,leakages in oil pipelines,and the extensive use of pesticides;PAH contaminants include petroleum hydrocarbons(PHCs),halogenated hydrocarbons,chlorophenols,and *** using microorganisms such as bacteria and fungi is developing as an effective and promising technique to remediate PAHs from the *** to their remediation efficiency,this method is environmentally friendly and represents a novel approach for reducing the risk of PAHs to human health and the *** may be applied in bioremediation,and will not only induce fewer toxic effects but also reduce the effective overall time and costs *** article provides a summary of the application of nanomaterials,bacteria,and fungi to PAH remediation;we review and briefly discuss the structure,properties,sources,fate,toxicity,and remediation approaches involved in the remediation of PAH-polluted sites.

关键词： bioremediation microorganisms pesticides persistent organic pollutants petroleum hydrocarbons