Search results for "Amide"

Amide additives in polyolefins and imperfections in blown films

1985

Filmability and properties of compatibilized PA6/LDPE blends

2005

Blends of low density polyethylene (LDPE) and polyamide 6 (PA6), compatibilized with an ethylene-acrylic acid copolymer (EAA), either alone or combined with a low molar mass bis-oxazoline compound (PBO), have been processed in film blowing operations and the properties of the films have been investigated. Without of compatibilization, the filmability of the blend was very poor and no significant specimen was collected. As a result of the reactive compatibilization, the blends with EAA and even more with the EAA-PBO, were processed successfully in film blowing. The films of the quaternary blends were shown to possess satisfactory mechanical properties as a result of fine and stable morpholog…

Grafted squaramide monoamine nanoparticles as simple systems for sulfate recognition in pure water.

2012

New simple systems formed by a chain containing a squaramide function and a quaternised amine group attached to boehmite or silica-coated boehmite nanoparticles are able to discriminate anions in pure water.

Phylogeography and genetic divergence of some lymnaeid snails, intermediate hosts of human and animal fascioliasis with special reference to lymnaeid…

1997

Abstract A population genetic study using starch gel electrophoresis was performed on populations of several species of lymnaeid snails acting as intermediate hosts for Fasciola hepatica (Trematoda, Plathyhelminth). Lymnaea viatrix was collected in 16 sites from the Bolivian Northern Altiplano. L. cubensis were obtained in one site from Venezuela, one site from Guadeloupe, three sites from Cuba and one site from the Dominican Republic. L. truncatula were collected in one site from France, one from Portugal and one from Morocco. Multilocus enzyme electrophoresis (MEE) were determined for 282 snails at 18 loci. A complete monomorphism was encountered at each geographic site. However, among th…

Isolation and toxicity of Bacillus thuringiensis from potato-growing areas in Bolivia

2004

Bacillus thuringiensis was isolated from 116 samples collected in high altitude potato-growing areas in Bolivia. In these regions, main potato pests are the potato tuberworm Phthorimaea operculella, and the Andean weevils Premnotrypes latithorax and Rhigopsidius tucumanus. B. thuringiensis was found in 60% of the samples. The main percentage of samples with B. thuringiensis was found in larvae of R. tucumanus (78%). Bioassays were performed with 112 isolates. None resulted toxic to either larvae or adults of the two Andean weevils. However, 18 isolates from this study showed more toxicity against the beet armyworm Spodoptera exigua than the standard strain var. kurstaki isolated from DELFIN…

Microglial involvement in neuroplastic changes following focal brain ischemia in rats.

2009

The pathogenesis of ischemic stroke is a complex sequence of events including inflammatory reaction, for which the microglia appears to be a major cellular contributor. However, whether post-ischemic activation of microglial cells has beneficial or detrimental effects remains to be elucidated, in particular on long term brain plasticity events. The objective of our study was to determine, through modulation of post-stroke inflammatory response, to what extent microglial cells are involved in some specific events of neuronal plasticity, neurite outgrowth and synaptogenesis. Since microglia is a source of neurotrophic factors, the identification of the brain-derived neurophic factor (BDNF) as…

A new form of tumor and fetal collagen that binds laminin.

1993

Human breast and colon carcinoma tissues contain a form of collagen, not described before, composed of alpha 1 chains of similar size (approximately 100 kDa) but different charge. The three constitutive chains, separated by two-dimensional electrophoresis, are a unique acidic component, undetectable in other collagen types, with an apparent isoelectric point of 4-5, and two more basic components displaying the same electrophoretic behavior as alpha 1(III) and alpha 1(I), respectively. The acidic chain is structurally distinct from alpha 1(I) and displays a cyanogen bromide-derived fragment of similar size to CB5(III). This collagen in its native state is resistant to trypsin and metalloprot…

One-Pot Synthesis and AFM Imaging of a Triangular Aramide Macrocycle

2014

Macrocyclizations in exceptionally good yields were observed during the self-condensation of N-benzylated phenyl p-aminobenzoates in the presence of LiHMDS to yield three-membered cyclic aramides that adopt a triangular shape. An ortho-alkyloxy side chain on the N-benzyl protecting group is necessary for the macrocyclization to occur. Linear polymers are formed exclusively in the absence of this Li-chelating group. A model that explains the lack of formation of other cyclic congeners and the demand for an N-(o-alkoxybenzyl) protecting group is providedon the basis of DFT calculations.High-resolution AFM imaging of the prepared molecular triangles on a calcite(10.4) surface shows individual …

Relationship Between Thymidylate Synthase and p53 and Response to FEC Versus Taxane Adjuvant Chemotherapy for Breast Carcinoma

2011

Many drugs can be used for adjuvant therapy of breast cancer, including anthracyclines, cyclophosphamide, 5-fluorouracil (5-fU) and, recently, taxanes (TXT) have shown promising results. 5-FU blocks thymidylate synthase (TS) which cross-links p53 mRNA, inhibiting its synthesis. TS overexpression is one of the main mechanisms involved in 5-FU drug resistance. Enough p53 mutations can confer resistance to chemotherapy using anthracyclines and 5-FU, while are associated with improved responses to TXT. The aim of this study was to examine the TS and p53 levels in tumor samples and to compare the efficacy of FEC (5-FU, epirubicin, cyclophosphamide) and TXT chemotherapy in a group of patients wit…

Improving sensitivity in simultaneous determination of copper carboxylates by nonaqueous capillary electrophoresis

2005

Abstract A new method of nonaqueous capillary electrophoresis (NACE) with UV spectrophotometric detection was developed and optimized for the simultaneous determination of seven carboxylates (trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (CDTA), diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA), nitrilotriacetic acid (NTA), 1,3-diaminopropane-N,N,N′,N′-tetraacetic acid (PDTA) and triethylenetetraaminehexaacetic acid (TTHA)) as copper complexes. The method development was carried out by using a fused silica capillary. Background electrolyte (BGE) was optimized and the best separation a…