Search results for "Reaction"
showing 10 items of 6134 documents
Analysis of the p53 and MDM-2 gene in acute myeloid leukemia
1996
The MDM-2 (murine double minute 2) gene codes for a cellular protein that can bind to the p53 tumor suppressor gene product, thereby functioning as a negative regulator of p53. In order to define the role of the MDM-2 gene in the pathogenesis of human acute myeloid leukemia, the expression and the sequence of the MDM-2 gene were examined in samples of bone marrow and/or peripheral mononuclear cells of 38 patients by using immunostaining, polymerase chain reaction (PCR), single strand conformation polymorphism, and sequencing. Immunohistochemical staining detected a weak accumulation of the MDM-2 protein in AML patients of FAB classification M4 and M5. RT-PCR analysis revealed a heterogeneou…
Investigation of PTEN promoter methylation in ameloblastoma
2019
Background Phosphatase and tensin homolog (PTEN) acts as a tumor suppressor gene. Inactivation of PTEN has been reported in various types of cancers. PTEN promoter methylation possibly underlies PTEN inactivation, which results in tumorigenesis. The aim of this study was to investigate whether PTEN promoter methylation contributes to PTEN inactivation in ameloblastoma and its associated protein expression. Material and Methods In total, 20 fresh-frozen ameloblastoma samples were evaluated for PTEN promoter methylation using methylation-specific polymerase chain reaction (MS-PCR). A subset of 10 paraffin-embedded ameloblastoma samples was examined for PTEN expression through immunohistochemi…
Examination of Escherichia coli from poultry for selected adhesin genes important in disease caused by mammalian pathogenic E. coli
2001
A collection of 1601 extraintestinal and intestinal Escherichia coli isolated from chickens, turkeys and ducks, in Belgium, France and Spain, was hybridised with gene probes specific for fimbrial and afimbrial adhesins (F17, F18, SSfa/F1C, Bfp, Afa, Cs31A, IntiminEae, Aida-1) of intestinal, urinary and invasive E. coli of mammals and with a probe specific for the P (Pap/Prs) fimbrial adhesin of urinary and invasive E. coli of mammals and birds. Three hundred and eighty-three strains (23.9%) were P-positive, 76 strains (4.8%) were Afa-positive, 75 strains (4.7%) were F17-positive, 67 strains (4.2%) were S-positive, 23 (1.4%) were Intimin-positive, and all were F18-, Cs31A-, Aida1- and Bfp-ne…
A Short Synthesis of Polysubstituted Pyrrolidines via α-(Alkylideneamino)nitriles
2004
α-(Alkylideneamino)nitriles can be deprotonated under mild conditions. Their conjugated anions react with enones in a 1,4-addition to yield δ-keto-α-(alkylideneamino)nitriles which in turn can be reduced to form pyrrolidines in a one-pot reaction sequence.
Addition reactions of azoesters with 2-thioquinazolinones
1981
Reaction between diethyl azodicarboxylate (I) and 1,2,3,4-tetrahydro-2-thioquinazolin-4-one (II), as a cyclic model of thiourea, both in alcoholic medium and in inert solvents has been investigated. By carrying out the reaction in an inert solvent, it was possible to isolate an intermediate. Evidence is presented that the intermediate, in turn, was converted into the final products. Structures were unequivocally assigned by mass spectrometry.
Double asymmetric intramolecular aza-Michael reaction: a convenient strategy for the synthesis of quinolizidine alkaloids.
2021
A new methodology to access the quinolizidine skeleton in an asymmetric fashion was devised. It involves two consecutive intramolecular aza-Michael reactions of sulfinyl amines bearing a bis-enone moiety, in turn generated by a monodirectional cross metathesis reaction. The sequence, which takes place with excellent yields and diastereocontrol, was applied to the total synthesis of alkaloids lasubine I and myrtine.
LaXp180, a mammalian ActA-binding protein, identified with the yeast two-hybrid system, co-localizes with intracellular Listeria monocytogenes
2001
The Listeria monocytogenes surface protein ActA is an important virulence factor required for listerial intracellular movement by inducing actin polymerization. The only host cell protein known that directly interacts with ActA is the phosphoprotein VASP, which binds to the central proline-rich repeat region of ActA. To identify additional ActA-binding proteins, we applied the yeast two-hybrid system to search for mouse proteins that interact with ActA. A mouse cDNA library was screened for ActA-interacting proteins (AIPs) using ActA from strain L. monocytogenes EGD as bait. Three different AIPs were identified, one of which was identical to the human protein LaXp180 (also called CC1). Bind…
Photo Induced Radical Reactions
2012
This article discusses a number of reactions of potential synthetic interest occurring through photochemically generated organic radicals. Emphasis is placed on the nature of the resulting photoproducts, whose formation is discussed on a mechanistic basis. If available, experimental evidence (obtained by laser flash photolysis or related time-resolved techniques) is provided. The material is organized according to the reaction types, for instance, homolytic cleavage, mesolytic cleavage, radical addition, and oxidative or reductive electron transfer. In addition to the classical carboncarbon or carbonhydrogen bond breaking processes, such as the Norrish type I reaction, the hydrogen abstract…
Functional coupling of nitric oxide synthase and soluble guanylyl cyclase in controlling catecholamine secretion from bovine chromaffin cells
1997
This study was designed to evaluate whether the enzymes of the nitric oxide/cyclic-GMP pathway, nitric oxide synthase and soluble guanylyl cyclase, are functionally coupled in controlling catecholamine secretion in primary cultures of bovine chromaffin cells. In immunocytochemical studies, 80-85% of the tyrosine hydroxylase-positive chromaffin cells also possessed phenylethanolamine-N-methyltransferase, f1p4cating their capability to synthesize epinephrine. Immunoreactivity for neuronal-type nitric oxide synthase was found in over 90% of all chromaffin cells. Reverse transcription-polymerase chain reaction also demonstrated neuronal-type nitric oxide synthase messenger RNA. Immunoreactivity…
Angular momentum population in fragmentation reactions
2009
Neutron-deficient nuclei with N = 126 have been populated following projectile fragmentation of a 238U beam with energy 1 GeV/A. The decay of several previously reported isomers has been measured. This will allow us to calculate high-spin isomeric ratios and compare them with model calculations to allow a better understanding of the reaction mechanism. Algora, Alejandro, Alejandro.Algora@ific.uv.es ; Molina Palacios, Francisco Manuel, Francisco.Molina@ific.uv.es ; Rubio Barroso, Berta, Berta.Rubio@ific.uv.es