Search results for " molecule"

Post-weaning social isolation rearing influences the expression of molecules related to inhibitory neurotransmission and structural plasticity in the…

2012

Several lines of evidence indicate that alterations in the structure of neural circuits and inhibitory neurotransmission underlie the physiopathogenesis of schizophrenia. Most of the studies on these parameters have been focused on cortical regions and, despite the crucial role of the amygdala in this psychiatric disorder, there is less information on this region. In order to expand this knowledge, we have studied the expression of molecules related to inhibitory neurotransmission and structural plasticity in rats subjected to post-weaning isolation rearing, an animal model that reproduces several core symptoms of schizophrenia. We have analyzed, using qRT-PCR and immunohistochemistry, the …

Increased airway inflammatory cells in endurance athletes: what do they mean?

2003

Inflammatory cells are increased in the airways of endurance athletes, but their role in causing exercise-induced respiratory symptoms and bronchoconstriction, or their possible long-term consequences, are uncertain.To put the results of athlete studies in perspective, by analysing the pathogenesis of airway cell changes and their impact on respiratory function.Athletes of different endurance sports at rest showed increased airway neutrophils. Elite swimmers and skiers also showed large increases in airway eosinophils and lymphocytes, possibly related to chronic, exercise-related exposure to irritants or cold and dry air, respectively. Post-exercise studies reported variable responses of ai…

L-selectin regulates human neutrophil transendothelial migration

2021

ABSTRACT The migration of circulating neutrophils towards damaged or infected tissue is absolutely critical to the inflammatory response. L-selectin is a cell adhesion molecule abundantly expressed on circulating neutrophils. For over two decades, neutrophil L-selectin has been assigned the exclusive role of supporting tethering and rolling – the initial stages of the multi-step adhesion cascade. Here, we provide direct evidence for L-selectin contributing to neutrophil transendothelial migration (TEM). We show that L-selectin co-clusters with PECAM-1 – a well-characterised cell adhesion molecule involved in regulating neutrophil TEM. This co-clustering behaviour occurs specifically during …

Characterization of neutrophil subsets in healthy human pregnancies

2014

We have previously shown that in successful pregnancies increased arginase activity is a mechanism that contributes to the suppression of the maternal immune system. We identified the main type of arginase-expressing cells as a population of activated low-density granulocytes (LDGs) in peripheral blood mononuclear cells and in term placentae. In the present study, we analyzed the phenotype of LDGs and compared it to the phenotype of normal density granulocytes (NDGs) in maternal peripheral blood, placental biopsies and cord blood. Our data reveal that only LDGs but no NDGs could be detected in placental biopsies. Phenotypically, NDGs and LDGs from both maternal and cord blood expressed diff…

Recent advances in polyoxometalate-containing molecular conductors

2005

The recent advances in crystalline conducting molecular materials based on polyoxometalates (POMs) and organic donors of the tetrathiafulvalene (TTF) family or perylene are discussed. We emphasise the wide diversity of POM structural types and the variety of packing architectures for the organic molecules that can be induced by these inorganic anions. Besides structural effects, we show that these hybrids can have interesting electric and/or magnetic properties. Thus, in the last years the common belief that this type of radical salts containing such big and highly charged anions could only exhibit poor conducting properties has been refuted by the production of new materials exhibiting hig…

Metabolic profiling reveals distinct variations linked to nicotine consumption in humans--first results from the KORA study.

2008

Exposure to nicotine during smoking causes a multitude of metabolic changes that are poorly understood. We quantified and analyzed 198 metabolites in 283 serum samples from the human cohort KORA (Cooperative Health Research in the Region of Augsburg). Multivariate analysis of metabolic profiles revealed that the group of smokers could be clearly differentiated from the groups of former smokers and non-smokers. Moreover, 23 lipid metabolites were identified as nicotine-dependent biomarkers. The levels of these biomarkers are all up-regulated in smokers compared to those in former and non-smokers, except for three acyl-alkyl-phosphatidylcholines (e.g. plasmalogens). Consistently significant r…

Synthesis of alkaloids by Stevens rearrangement of nitrile-stabilized ammonium ylides: (±)-laudanosine, (±)-laudanidine, (±)-armepavine, (±)-7-methox…

2013

The Stevens rearrangement of nitrile-stabilized ammonium ylides in conjunction with the reductive removal of the nitrile function permits the facile construction of α-branched amines from α-aminonitriles. We employed this reaction sequence for the preparation of (±)-laudanosine, (±)-laudanidine and (±)-armepavine, (±)-7-methoxycryptopleurine, and (±)-xylopinine from two closely related and readily accessible bicyclic α-aminonitriles. The final products were obtained in high to almost quantitative yields (71–98%) from the quaternary ammonium salts obtained by N-alkylation of these starting materials.

Pyrrolo[2,1-d][1,2,3,5]tetrazine-4(3H)-ones, a new class of azolotetrazines with potent antitumor activity.

2003

Pyrrolo[2,1-d][1,2,3,5]tetrazinones 10a-o, compounds that hold the deaza skeleton of the antitumor drug temozolomide, were prepared by reaction of 2-diazopyrroles 9 and isocyanates. Such a synthetic route represents, among those leading to azolotetrazinones reported so far, the only possible one since attempts to cyclize to the title ring system 2-amino-1-carbamoylpyrroles 11 or the mono substituted 2-triazenopyrrole 12 failed. Compounds 10 were screened at the National Cancer Institute (NCI) for their activity against a panel of about 60 human tumor cell lines. Most of them possess remarkable antineoplastic activity having GI(50) values in the low micromolar or sub-micromolar range and rea…

Bicyclic 5-5 Systems with One Ring Junction Nitrogen Atom: One Extra Heteroatom 1:0

1996

Aminolysis of monoacetyl derivatives of 2,2′ -dihydroxydiphenylmethanes

1974

A neighboring group effect was found for the aminolysis of the second acetyl group in acetates of 2,2′-dihydroxydiphenylmethane derivatives containing a nitrophenol and a methylphenol unit. Kinetic measurements with an excess of n-butylamine in dioxane were done with 2-(2-hydroxy-3, 5-dinitrobenzyl)-4-methylphenyl acetate (1), 2-(2-hydroxy-5-nitro-benzyl)-4-methylphenyl acetate (2), and 2-(2-hydroxy-3-nitro-5-methylbenzyl)-4-methyl-phenyl acetate (3). The maximum rate was found for compound 2. When the concentration of n-butylamine was varied over a large range, the results obtained for compound 2 could be explained best, by assuming that the acetyl group in the methylphenol unit is aminoli…