Search results for "Paraformaldehyde"

Maxillary bone necrosis following the use of formaldehyde containing paste: management and case series

2007

Paraformaldehyde is used both as a disinfectant and to devitalise inflamed pulps when local anaesthesia is ineffective. Despite the clinical benefits, paraformaldehyde is not confined to the pulp, but penetrates the dentine and is gradually released as formaldehyde. This case series describes the effects on periodontal and bone tissues of paraformaldehyde used as a devitalising or disinfectant agent.

2014

Purpose The removal of excessive melanin pigments that obscure ocular tissue morphology is important to address scientific questions and for differential diagnosis of ocular tumours based on histology. Thus, the goal of the present study was to establish an effective and fast melanin bleaching method for paraffin and frozen mouse and human ocular tissues. Methods Paraffin-embedded and frozen ocular specimens from mice and human donors were subjected to bleaching employing two methods. The first employed potassium permanganate (KMnO4) with oxalic acid, and the second 10% hydrogen peroxide (H2O2). To determine optimal bleaching conditions, depigmentation was carried out at various incubation …

The LepR-mediated leptin transport across brain barriers controls food reward

2018

Objective Leptin is a key hormone in the control of appetite and body weight. Predominantly produced by white adipose tissue, it acts on the brain to inhibit homeostatic feeding and food reward. Leptin has free access to circumventricular organs, such as the median eminence, but entry into other brain centers is restricted by the blood–brain and blood–CSF barriers. So far, it is unknown for which of its central effects leptin has to penetrate brain barriers. In addition, the mechanisms mediating the transport across barriers are unclear although high expression in brain barriers suggests an important role of the leptin receptor (LepR). Methods We selectively deleted LepR in brain endothelia…

Differences in the composition of inflammatory cell infiltrate in lens-induced uveitis under therapy with allopurinol or steroids.

2001

Purpose The aim of this study was to compare the qualitative changes in the composition of inflammatory cell infiltrate in lens-induced uveitis (LIU) under treatment with allopurinol (Allo), methylprednisolone (Pred) or the two drugs combined (Allo/Pred). Methods Twenty male Wistar rats were sensitized with lens proteins for eight weeks. Intravenous (IV) therapy was started after anterior capsule disruption in one eye of each animal. Five rats were randomly assigned to each of the four groups: controls, Allo (50 mg/kg bw), Pred (7.5 mg/kg bw) and Allo/Pred (50 mg/7.5 mg per kg bw). Eyes were enucleated 24 hours later and fixed in paraformaldehyde/glutaraldehyde. Sections at three levels wer…

Monoclonal antibodies SMI 311 and SMI 312 as tools to investigate the maturation of nerve cells and axonal patterns in human fetal brain

1998

Neurofilaments, which are exclusively found in nerve cells, are one of the earliest recognizable features of the maturing nervous system. The differential distribution of neurofilament proteins in varying degrees of phosphorylation within a neuron provides the possibility of selectively demonstrating either somata and dendrites or axons. Non-phosphorylated neurofilaments typical of somata and dendrites can be visualized with the aid of monoclonal antibody SMI 311, whereas antibody SMI 312 is directed against highly phosphorylated axonal epitopes of neurofilaments. The maturation of neuronal types, the development of area-specific axonal networks, and the gradients of maturation can thus be …

Experimental and theoretical DFT study of the reaction of 3-amino-1,2-diols with dichloromethane and paraformaldehyde

2004

Abstract The reactions of 3-phenyl-3-methylamino-1,2-propanediol 1a and 3-[(tert-butyldimethylsilyl)oxy]-1-methylamino-1-phenyl-2-propanol 1b with (CH2O)n and CH2Cl2 are appropriate procedures for the preparation of 1,3-oxazines or 1,3-oxazolidines under proper selection of kinetic or thermodynamic reaction conditions. The reaction of 1b with (CH2O)n or CH2Cl2, affords the oxazolidine 2b under kinetic conditions and then this compound can be slowly converted into 5-[(tert-butyldimethylsilyl)oxy]-3-methyl-4-phenyl-3,4,5,6-tetrahydro-2H-1,3-oxazine 3b under thermodynamic control. The mechanism proposed for this transformation and the effect of polar solvents on the acceleration of the reactio…

Insertion Reactions of Neutral Phosphidozirconocene Complexes as a Convenient Entry into Frustrated Lewis Pair Territory

2016

International audience; Neutral phosphidozirconocene complexes [Cp2Zr(PR2)Me] (Cp=cyclopentadienyl; 1a: R=cyclohexyl (Cy); 1b: R=mesityl (Mes); 1c: R=tBu) undergo insertion into the Zr-P bond by non-enolisable carbonyl building blocks (O=CRR), such as benzophenone, aldehydes, paraformaldehyde or CO2, to give [Cp2Zr(OCRRPR2)Me] (3-7). Depending on the steric bulk around P, complexes 3-7 react with B(C6F5)(3) to give O-bridged cationic zirconocene dimers that display typical frustrated Lewis pair (FLP)/ambiphilic ligand behaviour. Thus, the reaction of {[Cp2Zr(-OCHPhPCy2)][MeB(C6F5)(3)]}(2) (10a) with chalcone results in 1,4 addition of the Zr+/P FLP, whereas the reaction of {[Cp2Zr(-OCHFcPCy…

Anti-inflammatory Function of High-Density Lipoproteins via Autophagy of IκB Kinase

2015

Background & Aims: Plasma levels of high-density lipoprotein (HDL) cholesterol are frequently found decreased in patients with inflammatory bowel disease (IBD). Therefore, and because HDL exerts anti-inflammatory activities, we investigated whether HDL and its major protein component apolipoprotein A-I (apoA-I) modulate mucosal inflammatory responses in vitro and in vivo. Methods: The human intestinal epithelial cell line T84 was used as the in vitro model for measuring the effects of HDL on the expression and secretion of tumor necrosis factor (TNF), interleukin-8 (IL-8), and intracellular adhesion molecule (ICAM). Nuclear factor-κB (NF-κB)-responsive promoter activity was studied by …

Über die Synthese von o-Acylamino-ß-dimethylamino-propiophenonen 1. Mitt.: Verhalten von o-Nitro- und o-Carbäthoxyamino-acetophenon bei der Mannich-R…

1970

Das bei der Mannich-Reaktion von o-Carbathoxyamino-acetophenon mit Paraformaldehyd und Dimethylamin-hydrochlorid erhaltene Kondensationsprodukt wurde als ein Gemisch von o-Carbathoxyamino-β-dimethylamino-propiophenon und o-Carbathoxyamino-α-dimethylaminomethyl-acrylophenon identifiziert. Durch Variation der Versuchsbedingungen konnte das Acrylophenonderivat als Hauptprodukt erhalten werden. Es war durch Saurekatalyse in 1-N-Carbathoxy-3-dimethylaminomethyl-4-oxo-1,2,3,4-tetrahydrochinolin uberfuhrbar. Synthesis of o-Acylamino-β-dimethylamino-propiophenones The aminomethylation product of o-carbethoxyamino-acetophenone, paraformaldehyde and dimethylamine-hydrochloride was identified as a mix…

Synthesis of pillar[7]arene

2012

Abstract The first synthesis of pillar[7]arene is reported with two methods. Method A: the FeCl 3 -catalyzed condensation reaction of 1,4-dimethoxybenzene ( 1 ) with paraformaldehyde in CHCl 3 gave dimethoxypillar[7]arene ( 3 ). Method B: the p -toluenesulfonic acid catalyzed condensation reaction of 2,5-bis(benzyloxymethyl)-1,4-dimethoxybenzene ( 2 ) in CH 2 Cl 2 gave compound 3 . Demethylation of 3 with BBr 3 gave pillar[7]arene ( 4 ). The pillar[7]arene might be a perspective macrocyclic host in host–guest chemistry.