Search results for " Vitro"
showing 10 items of 2728 documents
Cholestenon in Rattennebennieren
1970
For the first time it has been proven that cholest-4-ene-3-one is an endogenous constituent of adrenal tissue. Concentrations of cholestenone in quartered rat adrenals after 3 hours of in vitro incubation were comparable to those of progesterone. However, from specific radioactivities of tissue cholesterol and progesterone and from those of tissue cholestenone and progesterone after incubations with either 4-14C-cholesterol or 4-14C-cholestenone it has been concluded that, at best, cholestenone plays a minimal role as a C27-intermediate of corticosteroid biosynthesis.
Effects of indomethacin on muscarinic inhibition of endogenous noradrenaline release from rat isolated trachea
1993
The release of endogenous noradrenaline from rat isolated tracheae was evoked by electrical field stimulation (3 Hz, 540 pulses) in the presence of yohimbine, desipramine and tyrosine. The muscarine receptor agonist oxotremorine concentration-dependently inhibited the evoked release of noradrenaline by 95% at 1 μmol/l, EC50 values in two series of experiments 41 and 57 nmol/l, respectively. The effect of oxotremorine was antagonized by the non-selective muscarine receptor antagonist scopolamine (10–1000 nmol/l) in a manner suggesting a simple competitive interaction (slope of Schild plot −0.94; pA2 value 8.88). However, the M2 selective muscarine receptor antagonist methoctramine (0.1–10 μm…
Polypeptides controlling hematopoietic cell development and activation. I. In vitro results.
1989
Recombinant DNA technology has been central in answering some of the most relevant questions in the research of regulation of the functional status of hematopoietic progenitor cells and their progeny. This leading article will focus on recent results that have emerged from studies utilizing recombinant molecules that control hematopoietic blood cell development and activation. The following features will be detailed: The molecular and biological characteristics and biochemistry of hematopoietic growth factors, synergizing factors and releasing factors, their role in the regulation of hematopoiesis and activation of normal and leukemic cells, their cellular sources, and regulation of product…
Cardiac pacemaker function of HCN4 channels in mice is confined to embryonic development and requires cyclic AMP.
2008
Important targets for cAMP signalling in the heart are hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels that underlie the depolarizing 'pacemaker' current, I(f). We studied the role of I(f) in mice, in which binding of cAMP to HCN4 channels was abolished by a single amino-acid exchange (R669Q). Homozygous HCN4(R669Q/R669Q) mice die during embryonic development. Prior to E12, homozygous and heterozygous embryos display reduced heart rates and show no or attenuated responses to catecholaminergic stimulation. Adult heterozygous mice display normal heart rates at rest and during exercise. However, following beta-adrenergic stimulation, hearts exhibit pauses and sino-atrial…
Modulation of IL-2, IFN-γ, TNF-α and IL-4 production in mice of different ages by thymopentin
1992
The effect of an immunomodulator drug thymopentin (TP5) on the production of various cytokines (IFN-gamma, IL-2, IL-4, TNF-alpha) in mice of different ages has been studied. TP5 enhanced IL-2, TNF-alpha and IFN-gamma production but reduced the IL-4 secretion by splenocytes from aged mice (greater than 120 week old) in vitro. However, it had no effect on the IL-2, IFN-gamma, TNF-alpha or IL-4 production by splenocytes from young and adult mice. TP5 injected subcutaneously was able to induce high levels of IL-2 production by splenocytes from all groups of mice. The TP5 effect on TNF-alpha and IFN-gamma was similar, even though it was significant only in old mice. Furthermore, TP5 was able to …
Embryologic outcome and secretome profile of implanted blastocysts obtained after coculture in human endometrial epithelial cells versus the sequenti…
2008
Objective To compare embryologic and clinical outcomes in terms of preimplantation development, implantation, pregnancy rates, and secretome profile of implanted blastocysts from the preimplantation genetic diagnosis program grown in sequential versus endometrial epithelial cell (EEC) coculture system. Design Retrospective clinical study and prospective experimental study. Setting In vitro fertilization clinical unit and university research laboratory. Intervention(s) Blastomere biopsy, embryo culture, blastocyst transfer, and protein analysis of the media conditioned from implanted embryos obtained from coculture and sequential systems. Main Outcome Measure(s) Clinical study: blastocyst, i…
Fragmentation of bile duct stones: a prospective systematic in vitro evaluation of argon plasma coagulation, cryotechnology, and water-jet technology
2009
Background and study aim Choledocholithiasis is a common disease in the West. Lithotripsy by mechanical methods using baskets and by laser or electrohydraulic methods varies in effectiveness. With argon plasma coagulation (APC), high temperatures are used for devitalization and fragmentation; cryogenic techniques use the selective controlled application of freeze-thaw cycles to devitalize pathological tissue; and the dissecting water jet exploits the high pressure action of a thin laminar jet. We aimed to assess the feasibility and effectiveness of APC, cryotechnology, and the dissecting water jet as options for the fragmentation of bile duct stones. Methods In an in vitro feasibility study…
Similarly increased congenital anomaly rates after intrauterine insemination and IVF technologies: a retrospective cohort study
2012
International audience; BACKGROUND: While intrauterine insemination (IUI), a simple, inexpensive and non-invasive technique, is the most used assisted reproduction technology (ART) worldwide, the risk of major birth defects following IUI is paradoxically not well documented. METHODS: Retrospective cohort study performed in Burgundy, France, over a 9-year period which consisted of the cross analysis of two prospective databases, the Burgundy perinatal network database and the database of the assisted conception units in Burgundy. A total of 1348 ART singletons [in vitro fertilization technologies (IVFT): n= 903; IUI: n= 445] matched with 4044 infants conceived naturally, 552 ART twins (IVFT:…
Metalloprotease meprin beta generates nontoxic N-terminal amyloid precursor protein fragments in vivo.
2011
Identification of physiologically relevant substrates is still the most challenging part in protease research for understanding the biological activity of these enzymes. The zinc-dependent metalloprotease meprin β is known to be expressed in many tissues with functions in health and disease. Here, we demonstrate unique interactions between meprin β and the amyloid precursor protein (APP). Although APP is intensively studied as a ubiquitously expressed cell surface protein, which is involved in Alzheimer disease, its precise physiological role and relevance remain elusive. Based on a novel proteomics technique termed terminal amine isotopic labeling of substrates (TAILS), APP was identified …
Toxocara canis infection induces antigen-specific IL-10 and IFNγ production in pregnant dogs and their puppies
2005
Toxocara canis (T. canis) is originally a parasite of canine bitches and their pups. The pathogenicity of T. canis infection is enhanced during pregnancy and puppyhood. The aim of this study was to investigate if modification of IFNgamma and IL-10 secretion occurs during infection in pregnant dogs and puppies. Analysis of cytokines secreted could let us hypothesize a role for IL-10 and/or IFNgamma in T. canis infection. We tested T. canis-specific production of IFNgamma and IL-10 by lymphocytes of pregnant dogs and their puppies after in vitro re-exposure to purified excretory/secretory antigen (ESAg) from T. canis. Blood mononuclear cells (BMC) isolated from pregnant dogs and their puppies…