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111.
Jean Ballongue Jamel Amine Henri Petitdemange Robert Gay 《FEMS microbiology letters》1986,35(2-3):295-301
Abstract The effects of acetic acid and butyric acid on acetate kinase, butyrate kinase and acetoacetate decarboxylase levels are studied. It is shown that acetate kinase biosynthesis is regulated by acetic acid whereas butyric acid has no effect. Acetate kinase specific activity is found to be maximal at the beginning of the fermentation, and decreases as acetic acid concentration increases in the medium. Butyrate kinase is not regulated by the end-product acids; its specific activity is constant during the fermentation. In the presence of acetic acid, acetoacetate decarboxylase biosynthesis represents a 4-fold increase in activity over a culture without acetate and a 1.7-fold increase over that obtained in presence of butyrate. The technique of fermentation used allows us to show that bacterial growth and solventogenesis may occur simultaneously. 相似文献
112.
Chemometric Tools to Highlight the Variability of the Chemical Composition and Yield of Lebanese Origanum syriacum L. Essential Oil 下载免费PDF全文
Raviella Zgheib Sylvain Chaillou Naim Ouaini Amine Kassouf Douglas Rutledge Desiree El Azzi Marc El Beyrouthy 《化学与生物多样性》2016,13(10):1326-1347
This study deals with the variation in the yield and composition of Lebanese Origanum syriacum L. essential oil (EO) according to harvesting time, drying methods used, and geographical location. Plant material was harvested twice a month all over 2013 and 2014 from Qartaba and Achkout located at high altitude and from Byblos at low altitude. EOs of the aerial parts were obtained by hydrodistillation. The highest yields were obtained at full flowering stage and slightly reduced after flowering. The GC/MS analysis revealed the presence of 50 components representing 90.49 – 99.82%, 88.79 – 100%, and 95.28 – 100% of the total oil extracted from plants harvested from Qartaba, Achkout, and Byblos, respectively. The major components in the oils were: carvacrol (2.1 – 79.8%), thymol (0.3 – 83.7%), p‐cymene (2.8 – 43.8%), thymoquinone (0.4 – 27.7%), γ‐terpinene (0.4 – 10.0%), octan‐3‐ol (0.3 – 4.9%), caryophyllene oxide (0.2 – 4.7%), oct‐1‐en‐3‐ol (0.3 – 3.7%), β‐caryophyllene (0.7 – 3.2%), cis‐sabinene hydrate (0.1 – 2.8%), terpinen‐4‐ol (0.1 – 2.8%), and α‐terpinene (0.2 – 2.2%). Independent components analysis (ICA) revealed that two groups were discriminated, reflecting compositional differences in the EOs profiles of the Lebanese oregano samples: O. syriacum grown in Qartaba and Achkout belongs to carvacrol chemotype, while O. syriacum grown in Byblos belongs to thymol chemotype. The flowering phase was the most productive period in terms of yield, bringing marked changes in the EO composition by increasing the amounts of carvacrol or thymol, and decreasing those of thymoquinone and p‐cymene. 相似文献
113.
Koufan Meriyem Mazri Mouaad Amine Essatte Amine Moussafir Sanae Belkoura Ilham El Rhaffari Lhoussaine Toufik Ibrahim 《Plant Cell, Tissue and Organ Culture》2020,140(2):369-378
Plant Cell, Tissue and Organ Culture (PCTOC) - European mistletoe (Viscum album) is a medicinal plant with significant anticancer properties. In vitro callus production provides an essential... 相似文献
114.
Céline Sanfiorenzo Marius I. Ilie Amine Belaid Fabrice Barlési Jér?me Mouroux Charles-Hugo Marquette Patrick Brest Paul Hofman 《PloS one》2013,8(1)
The diagnosis of non-small cell lung carcinoma (NSCLC) at an early stage, as well as better prediction of outcome remains clinically challenging due to the lack of specific and robust non-invasive markers. The discovery of microRNAs (miRNAs), particularly those found in the bloodstream, has opened up new perspectives for tumor diagnosis and prognosis. The aim of our study was to determine whether expression profiles of specific miRNAs in plasma could accurately discriminate between NSCLC patients and controls, and whether they are able to predict the prognosis of resectable NSCLC patients. We therefore evaluated a series of seventeen NSCLC-related miRNAs by quantitative real-time (qRT)-PCR in plasma from 52 patients with I-IIIA stages NSCLC, 10 patients with chronic obstructive pulmonary disease (COPD) and 20-age, sex and smoking status-matched healthy individuals. We identified an eleven-plasma miRNA panel that could distinguish NSCLC patients from healthy subjects (AUC = 0.879). A six-plasma miRNA panel was able to discriminate between NSCLC patients and COPD patients (AUC = 0.944). Furthermore, we identified a three-miRNA plasma signature (high miR-155-5p, high miR-223-3p, and low miR-126-3p) that significantly associated with a higher risk for progression in adenocarcinoma patients. In addition, a three-miRNA plasma panel (high miR-20a-5p, low miR-152-3p, and low miR-199a-5p) significantly predicted survival of squamous cell carcinoma patients. In conclusion, we identified two plasma miRNA expression profiles that may be useful for predicting the outcome of patients with resectable NSCLC. 相似文献
115.
Koufan Meriyem Belkoura Ilham Mazri Mouaad Amine Amarraque Abderrahim Essatte Amine Elhorri Hafsa Zaddoug Fatima Alaoui Tajlmolk 《Plant Cell, Tissue and Organ Culture》2020,141(1):217-227
Plant Cell, Tissue and Organ Culture (PCTOC) - Argan (Argania spinosa (L.) Skeels) is an endangered and endemic agroforestry species of Morocco highly appreciated for its nutraceutical properties.... 相似文献
116.
Boris Schwartz Mohamed Amine Benadjaoud Enora Cléro Nadia Haddy Chiraz El-Fayech Catherine Guibout Cécile Teinturier Odile Oberlin Cristina Veres Hélène Pacquement Martine Munzer Tan Dat N’Guyen Pierre-Yves Bondiau Delphine Berchery Anne Laprie Mike Hawkins David Winter Dimitri Lefkopoulos Jean Chavaudra Carole Rubino Ibrahima Diallo Jacques Bénichou Florent de Vathaire 《Radiation and environmental biophysics》2014,53(2):381-390
Bone sarcoma as a second malignancy is rare but highly fatal. The present knowledge about radiation-absorbed organ dose–response is insufficient to predict the risks induced by radiation therapy techniques. The objective of the present study was to assess the treatment-induced risk for bone sarcoma following a childhood cancer and particularly the related risk of radiotherapy. Therefore, a retrospective cohort of 4,171 survivors of a solid childhood cancer treated between 1942 and 1986 in France and Britain has been followed prospectively. We collected detailed information on treatments received during childhood cancer. Additionally, an innovative methodology has been developed to evaluate the dose–response relationship between bone sarcoma and radiation dose throughout this cohort. The median follow-up was 26 years, and 39 patients had developed bone sarcoma. It was found that the overall incidence was 45-fold higher [standardized incidence ratio 44.8, 95 % confidence interval (CI) 31.0–59.8] than expected from the general population, and the absolute excess risk was 35.1 per 100,000 person-years (95 % CI 24.0–47.1). The risk of bone sarcoma increased slowly up to a cumulative radiation organ absorbed dose of 15 Gy [hazard ratio (HR) = 8.2, 95 % CI 1.6–42.9] and then strongly increased for higher radiation doses (HR for 30 Gy or more 117.9, 95 % CI 36.5–380.6), compared with patients not treated with radiotherapy. A linear model with an excess relative risk per Gy of 1.77 (95 % CI 0.6213–5.935) provided a close fit to the data. These findings have important therapeutic implications: Lowering the radiation dose to the bones should reduce the incidence of secondary bone sarcomas. Other therapeutic solutions should be preferred to radiotherapy in bone sarcoma-sensitive areas. 相似文献
117.
Understanding the Rate Capability of High‐Energy‐Density Li‐Rich Layered Li1.2Ni0.15Co0.1Mn0.55O2 Cathode Materials 下载免费PDF全文
Xiqian Yu Yingchun Lyu Lin Gu Huiming Wu Seong‐Min Bak Yongning Zhou Khalil Amine Steven N. Ehrlich Hong Li Kyung‐Wan Nam Xiao‐Qing Yang 《Liver Transplantation》2014,4(5)
The high‐energy‐density, Li‐rich layered materials, i.e., xLiMO2(1‐x)Li2MnO3, are promising candidate cathode materials for electric energy storage in plug‐in hybrid electric vehicles (PHEVs) and electric vehicles (EVs). The relatively low rate capability is one of the major problems that need to be resolved for these materials. To gain insight into the key factors that limit the rate capability, in situ X‐ray absorption spectroscopy (XAS) and X‐ray diffraction (XRD) studies of the cathode material, Li1.2Ni0.15Co0.1Mn0.55O2 [0.5Li(Ni0.375Co0.25 Mn0.375)O2·0.5Li2MnO3], are carried out. The partial capacity contributed by different structural components and transition metal elements is elucidated and correlated with local structure changes. The characteristic reaction kinetics for each element are identified using a novel time‐resolved XAS technique. Direct experimental evidence is obtained showing that Mn sites have much poorer reaction kinetics both before and after the initial activation of Li2MnO3, compared to Ni and Co. These results indicate that Li2MnO3 may be the key component that limits the rate capability of Li‐rich layered materials and provide guidance for designing Li‐rich layered materials with the desired balance of energy density and rate capability for different applications. 相似文献
118.
Tao Li ;Marco Ceccarelli ;Minzhou Luo ;Med Amine Laribi ;Said Zeghloul 《仿生工程学报(英文版)》2014,11(4):497-505
In this paper, an experimental analysis of overcoming obstacle in human walking is carried out by means of a motion capture system. In the experiment, the lower body of an adult human is divided into seven segments, and three markers are pasted to each segment with the aim to obtain moving trajectory and to calculate joint variation during walking. Moreover, kinematic data in terms of displacement, velocity and acceleration are acquired as well. In addition, ground reaction forces are measured using force sensors. Based on the experimental results, features of overcoming obstacle in human walking are ana- lyzed. Experimental results show that the reason which leads to smooth walking can be identified as that the human has slight movement in the vertical direction during walking; the reason that human locomotion uses gravity effectively can be identified as that feet rotate around the toe joints during toe-off phase aiming at using gravitational potential energy to provide propulsion for swing phase. Furthermore, both normal walking gait and obstacle overcoming gait are characterized in a form that can provide necessary knowledge and useful databases for the implementation of motion planning and gait planning towards overcoming obstacle for humanoid robots. 相似文献
119.
This article is a review highlighting the application of the acoustic filter as a reliable cell retention device during the long-term perfusion of animal cell cultures. Critical operating parameters such as duty cycle, perfusion and re-circulation flow rates, acoustic power and backflush frequency are discussed with regard to influence on the separation efficiency and optimal operating ranges have been identified. Perfusion data gathered from the literature have been complemented with original data from a series of perfusion experiments carried out in the context of industrial projects for industrially relevant cell lines including NS0, HEK-293, SP2-derived hybridoma and insect cells in different serum-supplemented and serum-free media at different perfusion rates and acoustic chamber volumes. Finally, scale-up potential of the acoustic filter for large-scale industrial applications is discussed. 相似文献
120.
Novel fatty acid elongases and their use for the reconstitution of docosahexaenoic acid biosynthesis 总被引:1,自引:0,他引:1
Meyer A Kirsch H Domergue F Abbadi A Sperling P Bauer J Cirpus P Zank TK Moreau H Roscoe TJ Zähringer U Heinz E 《Journal of lipid research》2004,45(10):1899-1909
In algae, the biosynthesis of docosahexaenoic acid (22:6omega3; DHA) proceeds via the elongation of eicosapentaenoic acid (20:5omega3; EPA) to 22:5omega3, which is required as a substrate for the final Delta4 desaturation. To isolate the elongase specific for this step, we searched expressed sequence tag and genomic databases from the algae Ostreococcus tauri and Thalassiosira pseudonana, from the fish Oncorhynchus mykiss, from the frog Xenopus laevis, and from the sea squirt Ciona intestinalis using as a query the elongase sequence PpPSE1 from the moss Physcomitrella patens. The open reading frames of the identified elongase candidates were expressed in yeast for functional characterization. By this, we identified two types of elongases from O. tauri and T. pseudonana: one specific for the elongation of (Delta6-)C18-PUFAs and one specific for (Delta5-)C20-PUFAs, showing highest activity with EPA. The clones isolated from O. mykiss, X. laevis, and C. intestinalis accepted both C18- and C20-PUFAs. By coexpression of the Delta6- and Delta5-elongases from T. pseudonana and O. tauri, respectively, with the Delta5- and Delta4-desaturases from two other algae we successfully implemented DHA synthesis in stearidonic acid-fed yeast. This may be considered an encouraging first step in future efforts to implement this biosynthetic sequence into transgenic oilseed crops. 相似文献