Search results for "Amide"

Squaramide-Catalyzed Enantioselective Michael Addition of Pyrazol-3- ones to ortho-Quinone Methides

2020

A bifunctional squaramide catalyzed the enantioselective Michael addition of pyrazol-3- ones to ortho-quinone methides, generated in situ from 2-(1-tosylalkyl)phenols is presented. The corresponding chiral pyrazolones are obtained with good to excellent yields (27-98%) and enantiomeric excess (14-99% ee).

Electrophoresis of Unlabeled Proteins in a Sequencing Gel Apparatus

2000

Sphingomyelin inhibition of Ciona intestinalis (Tunicata) cytotoxic hemocytes assayed against sheep erythrocytes

1995

Hemocytes from the ascidian, Ciona intestinalis, are capable of lysing erythrocytes in vitro following cell membrane contact. With the aim of examining the mechanism of cytotoxicity, we performed inhibition experiments with lipid components of erythrocyte membranes. Cholesterol is not an inhibitor, whereas, among the phospholipids tested, (sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine) sphingomyelin inhibits the hemolytic activity of hemocytes. However, thin layer chromatography showed that sphingomyelinase activity was not contained in the chloroform-methanol extracts from hemocyte debris. The inhibition capacity of the components ceramide and phosphorylc…

SPHINGOLIPID TRANSPORT FROM THE TRANSGOLGI NETWORK TO THE APICAL SURFACE IN PERMEABILIZED MDCK CELLS

1992

AbstractWe have measured the transport of de novo synthesized fluorescent analogs of sphingomyelin and glucosylceramide from the trans-Golgi network (TGN) to the apical membrane in basolaterally permeabilized Madin-Darby canine kidney (MDCK) cells. Sphingolipid transport was temperature, ATP and cytosol dependent. Introduction of bovine serum albumin (BSA), which binds fluorescent sphingolipid monomer, into the permeabilized cells, did not affect lipid transport to the apical membrane. Both fluorescent sphingomyelin and glucosylceramide analogs were localized to the lumenal bilayer leaflet of isolated TGN-derived vesicles. These results strongly suggest that both sphingolipids are transport…

Induction of programmed cell death in human retinoblastoma Y79 cells by C2-ceramide.

1998

C2-ceramide, a cell-permeable analogue of ceramide, induced significant, dose- and time-dependent death in human retinoblastoma Y79 cells. Dying cells strongly displayed the morphology of apoptosis as characterized by microscopic evidence of cell shrinkage, membrane blebbing, nuclear and chromatin condensation and degeneration of the nucleus into membrane-bound apoptotic bodies. Upon induction of apoptosis Y79 cells evidence early phosphatidylserine externalization, as shown by annexin V-FITC. Apoptosis was also assessed by monitoring changes in cell granularity by staining with the combined fluorescent dyes acridine orange and ethidium bromide. C2-ceramide induced these morphological chang…

Mixed-ligand copper(ii)–sulfonamide complexes: effect of the sulfonamide derivative on DNA binding, DNA cleavage, genotoxicity and anticancer activity

2013

Four ternary complexes, [Cu(L1)2(bipy)] (1) [HL1 = N-(6-chlorobenzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide], [Cu(L2)2(bipy)] (2) [HL2 = N-(benzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide], [Cu(L3)2(bipy)]·1/2H2O (3) [HL3 = N-(5,6-dimethylbenzo[d]thiazol-2-yl)-4-methylbenzenesulfonamide] and [Cu(L4)2(bipy)] (4) [HL4 = N-(5,6-dimethylbenzo[d]thiazol-2-yl)benzenesulfonamide], were prepared and then characterized by X-ray crystallography, spectroscopy and magnetic measurements. Whereas the molecular structure of 1 and 2 consists of a discrete monomeric copper(II) species with a distorted square planar geometry, that of 3 and 4 consists of two independent molecules. In 3, both molecules pre…

Anti-inflammatory effects of chemically modified tetracyclines by the inhibition of nitric oxide and interleukin-12 synthesis in J774 cell line

2001

We investigated the effects of chemically modified tetracyclines (CMTs) on the production of nitric oxide (NO) and on the synthesis of some cytokines: tumour necrosis factor alpha (TNF-alpha), interleukin(IL)-10 and IL-12 in lipopolysaccharide (LPS)-treated J774 cell line. Furthermore, we studied the ability of these drugs to modify the viability in LPS-stimulated J774 macrophages. CMTs decreased, in a dose-dependent manner, inducible NO synthase (iNOS) activity and, consequently, nitrite formation in J774 cultures. The CMT-induced decrease in NO production is due to the inhibition of enzyme activity rather than to a direct effect on enzyme expression. The absence of the inhibition in mRNA …

Identification of a cell surface-associated protein involved in mouse neural cell aggregation by means of antibodies against the sponge aggregation f…

1989

Polyclonal antibodies were raised against the purified aggregation factor (AF) from the sponge Geodia cydonium to elucidate possible immunological relationships between adhesion molecules of lower multicellular eukaryotic systems (sponges) and those of vertebrates. This anti-AF recognized a series of polypeptides associated with the AF, among them also a polypeptide with a Mr of 47,000 (p47). The formation of the antibody-p47 immunocomplexes could be prevented by adsorbing the anti-AF with a brain extract from DBA/2J mice. Moreover, this brain polypeptide inhibited the AF-mediated aggregation of sponge cells. Interestingly, the anti-AF recognized a p37 molecule in the brains of 2- to 3-day-…

Mapping of phenytoin-inducible cytochrome P450 immunoreactivity in the mouse central nervous system

1991

Abstract The distribution of phenytoin-inducible cytochrome P450 in non-treated mouse brain and spinal cord was analysed immunohistochemically using polyclonal antibodies against phenytoin-induced mouse cerebral microsomal P450. This P450 protein was proved in Ouchterlony [Volk B. et al. (1988) Neurosci. Lett. 84 , 219–224], Western blot, and immunohistochemical analyses to be reactive to the specific antibodies and an IgG fraction raised against phenobarbital-induced rat liver microsomal P450IIB1. The phenytoin-induced P450 is designated P450IIB1 * because immunologically it is comparable with P450IIB1; however, it has not yet been analysed for other characteristics of this enzyme. Immunoc…

Anderson-Fabry Disease: A Multiorgan Disease

2013

Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by a deficiency of the enzyme α-galactosidase A . FD causes glycolipids, such as globotriaosylceramide (Gb3), to accumulate in the vascular endothelium of several organs (fig.2), including the skin, kidneys, nervous system, and heart, thereby triggering inflammation and fibrosis . These processes generally result in organ dysfunction, which is usually the first clinical evidence of FD. Patients with classic FD have various symptoms, eg, acroparesthesias, hypohidrosis, angiokeratomas, corneal opacities, cerebrovascular lesions, cardiac disorders, andrenal dysfunction.However, evolving knowledge about the natural course o…