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971.
BACTOX, a Rapid Bioassay That Uses Protozoa To Assess the Toxicity of Bacteria 总被引:2,自引:0,他引:2
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Wolfram Schlimme Marcello Marchiani Kurt Hanselmann Bernard Jenni 《Applied microbiology》1999,65(6):2754-2757
A new type of toxicity test based on the protozoan Tetrahymena pyriformis has been developed to assess the overall toxicity of bacterial strains given as prey. This simple and rapid test is able to detect toxicant-producing bacteria, which may present a biohazard. It can also be used for the risk assessment of microbes designed for deliberate release. 相似文献
972.
A Marcello A Loregian V de Filippis A Fontana T.R Hirst G Palùa 《FEMS microbiology letters》1996,136(1):39-44
Abstract The marine fish pathogen Vibrio sp. 60 has been used as a host for heterologous expression of the Escherichia coli heat-labile enterotoxin B-subunit and derivatives carrying a C-terminal extension. In this study, a chimeric enterotoxin B-subunit with an extension corresponding to the carboxy-terminal nine amino acids -Tyr-Ala-Gly-Ala-Val-Val-Asn-Asp-Leu-cooH from the small subunit of herpes simplex virus type 1-encoded ribonucleotide reductase, is shown to be proteolytically cleaved in the extracellular medium by a single protease that is secreted by the host strain. Such protease behaves as a typical metalloprotease, being inhibited by EDTA but not by a serine protease inhibitor. Purification and amino acid composition analysis of the two proteolysis products revealed a specific cleavage of the peptide bond between amino acids glycine and alanine of the nine amino acid extension with loss of activity. The above observation is relevant for the biotechnological exploitation of Vibrio sp. 60. 相似文献
973.
Expression of galanin receptor messenger RNAs in different regions of the rat gastrointestinal tract
Galanin effects are mediated by three G-protein-coupled receptors: galanin receptor 1 (GalR1), GalR2 and GalR3. We quantified mRNA levels of GalR1, GalR2 and GalR3 in the rat stomach, small and large intestine using real-time RT-PCR. All three GalR mRNAs were detected throughout the gut at different levels. GalR1 and GalR2 mRNA levels were higher in the large than in the small intestine. GalR2 mRNA was most abundant in the stomach. GalR3 mRNA levels were generally quite low. The differential regional distribution of GalRs suggests that the complex effects of galanin in the gut are the result of activating multiple receptor subtypes, whose density, subtype and signaling vary along the gastrointestinal tract. 相似文献
974.
The main engineering parameters (i.e., ion transport numbers in solution and electro-membranes; effective solute and water transport numbers; effective membrane surface area, membrane surface resistances, and limiting current intensity) affecting the recovery of sodium acetate from model solutions by electrodialysis (ED) were determined in accordance with a sequential experimental procedure. Such parameters allowed a satisfactory simulation of a few validation tests carried out under constant or step-wisely variable current intensity. The performance of this ED process was characterized in terms of a current efficiency (omega) of about 93% in the constant-current region, a water transport number (t(W)) of about 15, and a specific energy consumption (epsilon) increasing from 0.14 to 0.31 kWh/kg for a solute recovery yield of 95% as the current density (j) was increased from 112 to 337 A/m2. The specific resistance of the anion- or cation-exchange membranes were found to be three or two times greater than those measured in aqueous NaCl solutions and are to be used to design and/or optimize ED stacks involved in the downstream processing of acetic acid fermentation broths. 相似文献
975.
Several protocols and commercial kits are used for the extraction of nucleic acids from different plant tissues. Although
there are several procedures available to remove sugars, which hinder the extraction of clean genomic DNA, there are few to
assist with extraction of RNA. Those presently used include precipitations with ethylene glycol monobutyl ether or lithium
chloride (LiCl), or centrifugation in cesium chloride (CsCl) gradients, but these generally either do not allow high recovery
of RNA, are time consuming, rely on hazardous chemicals or need special equipment. Here we present the use of the simple cation,
Ca2+, which has been tested and shown to be very efficient for the precipitation of high molecular weight pectic sugars during
RNA extraction. Results are presented for different plant tissues, especially tissues of peach and apple fruits at varying
ripening stages. 相似文献
976.
Daniela Rossi Marta Rui Marcello Di Giacomo Dirk Schepmann Bernhard Wünsch Stefania Monteleone Klaus R. Liedl Simona Collina 《Bioorganic & medicinal chemistry》2017,25(1):11-19
Sigma Receptor (SR) modulators are involved in different signal transduction pathways, representing important pharmacological/therapeutic tools in several pathological conditions, such as neurodegenerative diseases and cancers. To this purpose, numerous compounds have been developed in order to target selectively one of the two subtypes (S1R and S2R) as chemotherapeutic agent. However, experiments have also shown that ligands which are able to bind both SR subtypes can be useful for the diagnosis and/or the treatment of cancers. Therefore, the discovery of compounds with good affinity towards both S1R and S2R (‘pan-modulators’) is also of great interest and still represents a challenge up to now. For this reason, we synthesized novel arylalkylamines with the aim to obtain compounds with S1R and S2R affinity in the nM range and, by modeling quantitative structure–activity relationships (QSARs), we identified the essential structural features to obtain promising pan-compounds. 相似文献
977.
A Real‐World Multicentre Retrospective Study of Paclitaxel‐Bevacizumab and Maintenance Therapy as First‐Line for HER2‐Negative Metastatic Breast Cancer
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Teresa Gamucci Lucia Mentuccia Clara Natoli Isabella Sperduti Alessandra Cassano Andrea Michelotti Luigi Di Lauro Domenico Sergi Alessandra Fabi Maria G. Sarobba Paolo Marchetti Maddalena Barba Emanuela Magnolfi Marcello Maugeri‐Saccà Ernesto Rossi Valentina Sini Antonino Grassadonia Domenica Pellegrini Antonino Astone Cecilia Nisticò Franco Angelini Angela Vaccaro Arianna Pellegrino Claudia De Angelis Michela Palleschi Luca Moscetti Ilaria Bertolini Simonetta Buglioni Antonio Giordano Laura Pizzuti Patrizia Vici 《Journal of cellular physiology》2017,232(6):1571-1578
Bevacizumab in combination with taxanes in HER2‐negative metastatic breast cancer (MBC) patients has shown improved progression‐free survival (PFS), despite the lack of clear overall survival (OS) benefit. We performed a retrospective analysis to evaluate the impact of paclitaxel‐bevacizumab and of maintenance therapy with bevacizumab (BM) and endocrine therapy (ET) in the real‐world practice. We identified 314 HER2‐negative MBC patients treated in 12 cancer centers. Overall, the median PFS and OS were 14 and 40 months, respectively. Among the 254 patients potentially eligible for BM, 183 received BM after paclitaxel discontinuation until progression/toxicity. PFS and OS were improved in patients who had received BM in comparison with those potentially eligible but who did not receive BM (P< 0.0001 and P = 0.001, respectively). Results were confirmed when adjusting for propensity score. Among the 216 hormone‐receptor positive patients eligible for BM, a more favorable PFS and OS were observed when maintenance ET was administered (P < 0.0001). Multivariate analysis showed that PS, BM, number of disease sites and maintenance ET were related to PFS, while response and maintenance ET were related to OS. In hormone‐receptor positive patients, BM produced a significant PFS and a trend towards OS benefit only in absence of maintenance ET (P = 0.0007 and P = 0.06, respectively). In the triple‐negative subgroup, we observed a trend towards a better OS for patients who received BM (P = 0.06), without differences in PFS (P = 0.21). Our results confirmed the efficacy of first‐line paclitaxel‐bevacizumab in real‐world practice; both BM and maintenance ET significantly improved PFS and OS compared to no maintenance therapies. J. Cell. Physiol. 232: 1571–1578, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
978.
979.
980.
Patrizia Restani Marcello Duranti Paolo Cerletti Piera Simonetti 《Phytochemistry》1981,20(9):2077-2083
The seed globulins separated from Lupinus albus are all oligomeric proteins. Vicilins, i.e. globulins 4,5,6 and 7, and to a minor extent legumins, 相似文献