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41.
Walczak W Pipalia NH Soni M Faruqi AF Ralph H Maxfield FR Webb BL 《Combinatorial chemistry & high throughput screening》2006,9(9):711-718
The conversion of the genomic information produced by the recent sequencing projects into a comprehensive understanding of the human proteome has yet to occur. A new technology that represents a potential bridge between genomics and proteomics is reverse transfection. Reverse transfection cell microarrays are produced by overlaying cDNA arrays with mammalian cells, generating localized clusters of transfected cells with each cluster overexpressing a unique protein. This miniaturized cell-based microarray format affords parallel functional analysis of thousands of cDNA constructs in a high throughput format. In this report we document the development of a co-transfection methodology for reverse transfection applications. The demonstrated high co-transfection efficiency with a "marker" plasmid encoding for GFP enables the identification of transfected cells and eliminates the need for epitope-tagged constructs in cell-based high throughput screening applications using reverse transfection. This co-transfection method was used to study in parallel the structure/function of multiple versions of the v-Src protein using automated fluorescence microscopy. The wild-type v-Src protein and four mutants having insertions or deletions in the SH2 or SH3 domains displayed high levels of tyrosine kinase activity in HEK293T cells. Three other mutated v-Src proteins, including a kinase-dead version, were shown to be defective for tyrosine kinase activity. This reverse co-transfection approach is applicable for high throughput screening of both cDNA libraries and positional scanning recombinant protein libraries. 相似文献
42.
Joanna Brzeska Magda Morawska Aleksandra Heimowska Wanda Sikorska Wojciech Wałach Anna Hercog Marek Kowalczuk Maria Rutkowska 《Chemical Papers》2018,72(5):1249-1256
The surface morphology and thermal properties of polyurethanes can be correlated to their chemical composition. The hydrophilicity, surface morphology, and thermal properties of polyurethanes (differed in soft segments and in linear/cross-linked structure) were investigated. The influence of poly([R,S]-3-hydroxybutyrate) presence in soft segments and blending of polyurethane with polylactide on surface topography were also estimated. The linear polyurethanes (partially crystalline) had the granular surface, whereas the surface of cross-linked polyurethanes (almost amorphous) was smooth. Round aggregates of polylactide un-uniformly distributed in matrix of polyurethane were clearly visible. It was concluded that some modification of soft segment (by mixing of poly([R,S]-3-hydroxybutyrate) with different polydiols and polytriol) and blending of polyurethanes with small amount of polylactide influence on crystallinity and surface topography of obtained polyurethanes. 相似文献
43.
Tomer Rosen Wanda Navarra Prof. Vincenzo Venditto Prof. Moshe Kol 《Angewandte Chemie (International ed. in English)》2018,57(24):7191-7195
A magnesium complex of the type {ONNN}Mg‐HMDS wherein {ONNN} is a sequential tetradentate monoanionic ligand is introduced. In the presence of an alcohol initiator this complex catalyzes the living and immortal homopolymerization of the lactide enantiomers and ?‐caprolactone at room‐temperature with exceptionally high activities, as well as the precise block copolymerization of these monomers in a one‐pot synthesis by sequential monomer addition. Copolymers of unprecedented microstructures such as the PCL‐b‐PLLA‐b‐PDLA and PDLA‐b‐PLLA‐b‐PCL‐b‐PLLA‐b‐PDLA block–stereoblock microstructures that feature unique thermal properties are readily accessed. 相似文献
44.
Herman O. Desseyn Antonio C. Fabretti Wanda Malavasi 《Journal of chemical crystallography》1990,20(4):355-362
The title compound (C6H10CdN12S2) was prepared and characterized by means of X-ray, Raman, and IR measurements. The crystals are orthorhombic:Pbcn, (No. 60),a=9.558(2),b=9.491(2),c=15.898(2) Å,Z=4. The structure was solved by the heavy-atom method, and least-squares refinement of structural parameters led toR=0.021 (R
w
=0.020) for 863 independent reflections. The compound exhibits two-dimensional Cd(II) networks, with the 1,2,4-triazole molecule acting as a bidentate bridging ligand. The structure consists of centrosymmetric units, in which the cadmium atoms are coordinated in distorted octahedral geometries by six nitrogen atoms. Each cadmium atom is linked by four 1,2,4-triazole molecules, and two thiocyanate ions complete the octahedral coordination around the metal. Each 1,2,4-triazole molecule bridges two cadmium atoms. The NH and NH2 groups of the guanazole unit are involved in intermolecular hydrogen bonds. Infrared and Raman bands are diagnostic of the coordination environments around the metal atoms. 相似文献
45.
Wanda Mczka Anna Duda-Madej Aleksandra Grny Magorzata Grabarczyk Katarzyna Wiska 《Molecules (Basel, Switzerland)》2021,26(16)
One of the primary reasons for the search for new antimicrobial agents is the increasing and spreading resistance of microorganisms to previously used drugs. This is particularly important in the case of rapidly progressing infections that require the rapid administration of an appropriately selected antibiotic. However, along with the administration of antibiotics, complications in the disease-weakened body may arise in the form of systemic mycoses, viral infections, and protozoan infections. Therefore, there is an increasing interest among researchers focusing on the use of naturally occurring terpenic compounds in stand-alone or combined therapies with antibiotics. In this publication, the aim of our work is to present the results of a literature review on the antimicrobial activity of eucalyptol. 相似文献
46.
Wanda Sikorska Piotr Dacko Michał Sobota Joanna Rydz Marta Musioł Marek Kowalczuk 《Macromolecular Symposia》2008,272(1):132-135
Summary: Polyesters produced from renewable resources and susceptible to hydrolysis under the industrial composting conditions offer ecological advantages as compared to thermoplastics polymers and elastomers produced from fossil carbon sources. In this paper the degradation behaviour of polymer compositions of BTA, PLA and a-PHB in natural environment of industrial composting pile, consisting of leaves - 40%, branches - 30% and grass - 30%, have been presented. The extend of degradation was monitored by macroscopic observations of sample surfaces, changes of molecular weight, polydispersity and composition of the tested materials and their weight loss. 相似文献
47.
Dr. Giulia Neri Dr. Giuliana Mion Dr. Andrea Pizzi Dr. Wanda Celentano Dr. Linda Chaabane Prof. Michele R. Chierotti Prof. Roberto Gobetto Dr. Min Li Prof. Piergiorgio Messa Dr. Floryan De Campo Prof. Francesco Cellesi Prof. Pierangelo Metrangolo Prof. Francesca Baldelli Bombelli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):10057-10063
In the continuous search for multimodal systems with combined diagnostic and therapeutic functions, several efforts have been made to develop multifunctional drug delivery systems. In this work, through a covalent approach, a new class of fluorinated poly(lactic-co-glycolic acid) co-polymers (F-PLGA) were designed that contain an increasing number of magnetically equivalent fluorine atoms. In particular, two novel compounds, F3-PLGA and F9-PLGA, were synthesized and their chemical structure and thermal stability were analyzed by solution NMR, DSC, and TGA. The obtained F-PLGA compounds were proven to form in aqueous solution colloidal stable nanoparticles (NPs) displaying a strong 19F NMR signal. The fluorinated NPs also showed an enhanced ability to load hydrophobic drugs containing fluorine atoms compared to analogous pristine PLGA NPs. Preliminary in vitro studies showed high cell viability and the NP ability to intracellularly deliver and release a functioning drug. 相似文献
48.
Tomasz Wojciechowski Zbigniew Ochal Paweł Socha Łukasz Dobrzycki Wanda Ziemkowska 《应用有机金属化学》2020,34(12):e5961
t-Butyl derivatives play a significant role in the organometallic chemistry of group 13 metals. It was shown on the basis of reactions of t-Bu3Al·OEt2 with [p-RC6H4S(O)2C(H)2C(Ph) = O] (where R = CH3, Cl) β-keto sulfones that the structure of the reaction products depends on the purity of the aluminum compound used. In the reactions, in addition to the expected complexes [p-RC6H4S(O2)C(H) = C (Ph)-OAl(t-Bu)2] [where R = CH3 ( 2 ); R = Cl ( 4 )] possessing β-keto sulfone ligands, complexes with β-hydroxy sulfone ligands [p-RC6H4S(O2)C(H)2-C (Ph)-OAl(t-Bu)2] [where R = CH3 ( 1 ); R = Cl ( 3 )] were formed. Compounds 1 and 3 were the result of the hydroalumination reaction of the β-keto sulfone ligands with t-Bu2AlH, which is an impurity of t-Bu3Al. These compounds are obtained, for the first time, as intermediate products in the hydrogenation reaction of β-keto sulfones. In this work, during t-Bu3Al·OEt2 production t-Bu2AlH·OEt2 formed as a by-product. Re-examination of reaction conditions of AlCl3 with t-BuMgCl resulted in a control of the t-Bu2AlH·OEt2 by-product content in t-Bu3Al·OEt2. 相似文献
49.
Antonio C. Fabretti Giancarlo Franchini Wanda Malavasi Giorgio Peyronel 《Polyhedron》1985,4(6):989-992
Some palladium(II) halide complexes with 2,5-dimethyl- (DTZ), 2-amino- (ATZ), 2-amino-5-methyl- (MATZ), 2-ethylamino- (EATZ) and 2-mercapto-5-methyl-1,3,4-thiadiazole (MTTZ) have been prepared and studied: PdX2 · 2L (L = DTZ, ATZ, MATZ : X = Cl, Br, I; L = EATZ: X = Br, I; L = MTTZ: X = I), PdCl2 · 2.5EATZ, PdCl2 · 3MTTZ, PdBr2 · 1.5MTTZ and PdX2 · L (L = DTZ, ATZ, MATZ, EATZ: X = Cl, Br; L = MTTZ: X = Cl(H2O), Br). In the PdX2 · 2L, PdCl2 · 2.5EATZ and PdCl2 · 3MTTZ complexes the palladium ions are cis-(2X, 2L)-coordinated, the coordination sites being Nring for DTZ, NR2 for ATZ, MATZ, EATZ and C = S for MTTZ. PdBr2 · 1.5MTTZ may be formulated as cis[PdBr2-2L] · [PdBr2 · L]. In the PdX2 · L complexes the ligand very likely acts as bidentate by using a ring-nitrogen atom as the second coordination site. 相似文献
50.
The dependence of the electron charge distribution in alkali halides on the lattice constant is examined. It is found that in the case of NaCl the non-rigid behavior of the electron charge density calculated from first principles can be well understood if one starts from the free-ion functions and takes into account the mutual overlap between them. The relevance of our results for the structural properties of alkali halides is pointed out in connection with recent ab-initio calculations. 相似文献