Search results for "Endogeny"
showing 10 items of 147 documents
Direct Activation of Bax by p53 Mediates Mitochondrial Membrane Permeabilization and Apoptosis
2004
The tumor suppressor p53 exerts its anti-neoplastic activity primarily through the induction of apoptosis. We found that cytosolic localization of endogenous wild-type or trans-activation–deficient p53 was necessary and sufficient for apoptosis. p53 directly activated the proapoptotic Bcl-2protein Bax in the absence of other proteins to permeabilize mitochondria and engage the apoptotic program. p53 also released both proapoptotic multidomain proteins and BH3-only proteins [Proapoptotic Bcl-2family proteins that share only the third Bcl-2homology domain (BH3)] that were sequestered by Bcl-xL. The transcription-independent activation of Bax by p53 occurred with similar kinetics and concentra…
Cut-off method for endogeny of recursive tree processes
2016
Given a solution to a recursive distributional equation, a natural (and non-trivial) question is whether the corresponding recursive tree process is endogenous. That is, whether the random environment almost surely defines the tree process. We propose a new method of proving endogeny, which applies to various processes. As explicit examples, we establish endogeny of the random metrics on non-pivotal hierarchical graphs defined by multiplicative cascades and of mean-field optimization problems as the mean-field matching and travelling salesman problems in pseudo-dimension q>1.
Phenobarbital Induction of UDP-glucosyltransferase Activity in Drosophila melanogaster Meigen
2000
The inducibility of UDP-glucosyltransferase activities towards the exogenous substrates 1-naphthol and 2-naphthol and the endogenous metabolite xanthurenic acid was demonstrated in Drosophila melanogaster Meigen larvae and adults using phenobarbital as an inducer. In adults, a 3.5-fold increase of glucosyltransferase activity toward xanthurenic acid and a 2.0-fold increase of the activity toward exogenous substrates (1-naphthol and 2-naphthol) was found. In larvae, maximum induction of all three UDP-glucosyltransferase activities (2.5-fold and 1.5-fold increase of the activity toward the exogenous and endogenous substrates, respectively) was achieved when insects, reared on solid medium, we…
Endogenous Agents That Contribute to Generate or Prevent Ischemic Damage
2012
From single to multicellular organisms, protective mechanisms have evolved against endogenous and exogenous noxious stimuli. Over the past decades numerous signaling pathways by which the brain senses and reacts to such insults as neurotoxins, substrate deprivation and inflammation have been discovered. Research on preconditioning is aimed at understanding endogenous neuroprotection to boost it or to supplement its effectors therapeutically once damage to the brain has occurred, such as after stroke or brain trauma. Another goal of establishing preconditioning protocols is to induce endogenous neuroprotection in anticipation of incipient brain damage. Currently several endogenous neuroprote…
Endogenous DNA Damage and Its Relevance for the Initiation of Carcinogenesis
2011
Polysarcosine-functionalized lipid nanoparticles for therapeutic mRNA delivery
2020
Polysarcosine (pSar) is a polypeptoid based on the endogenous amino acid sarcosine (N-methylated glycine), which has previously shown potent stealth properties. Here, lipid nanoparticles (LNPs) for therapeutic application of messenger RNA were assembled using pSarcosinylated lipids as a tool for particle engineering. Using pSar lipids with different polymeric chain lengths and molar fractions enabled the control of the physicochemical characteristics of the LNPs, such as particle size, morphology, and internal structure. In combination with a suited ionizable lipid, LNPs were assembled, which displayed high RNA transfection potency with an improved safety profile after intravenous injection…
The Receptor Functions of Endogenous C1q, a Subcomponent of the First Component of Complement, on Peritoneal Macrophages
1982
Abstract C1q, the Fc recognizing subcomponent of the first complement component was shown to be synthesized by peritoneal macrophages. Evidence is presented that C1q serves during the secretion phase as Fc binding protein on the membrane of these macrophages. A dose-dependent inhibition of Fc rosette formation occured when the macrophages were pretreated with anti-C1q -F(ab') 2 . The C3b rosette formation was not affected. In addition, preincubation of peritoneal macrophages with anti-C1q -F(ab') 2 abolished specifically the polyanion mediated stimulation to secrete dose and time dependently lysosomal enzymes. There was no polyanion-induced enzyme release after incubation of polyanions with…
Glucose, Lactate, and Ketone Body Utilization by Human Mammary Carcinomas in Vivo
1985
Uncontrolled growth, one of the fundamental properties of malignant tumors, requires a great supply of energy. This energy can be derived from the use of a variety of substrates. Besides glucose oxidation and glucose breakdown to lactic acid, the turnover of endogeneous substrates such as amino acids, free fatty acids and ketone bodies is well documented in vitro. However, under in vivo conditions, only glucose utilization has been investigated in detail, using tumor isotransplants in rodents. For human tumors, only scarce data is available, derived mainly from clinical observations rather than from systematic studies.
In vitro synthesis of dopamine and noradrenaline in the isolated rat pineal gland: day-night variations and effects of electrical stimulation.
1989
: Isolated rat pineal glands were incubated in vitro in a medium containing [I4C]dopamine or [14C]tyrosine, and the tissue contents of l4C-labelled and total dopamine and noradrenaline were determined by HPLC followed by electrochemical detection and scintillation spectrometry. During incubation with [l4C]dopamine, the labelled amine accumulated in pineal glands and was partially converted into [l4C]noradrenaline. Nomifensine, a neuronal amine uptake blocker, largely inhibited the accumulation of [l4C]dopamine and the formation of [14C]noradrenaline. These experiments demonstrated dopamine β-hydroxylase activity in the sympathetic nerves of the pineal gland. During incubation with [14C]tyro…
Respiratory Parameters after Systemic Corticotropin-Releasing Hormone Administration
1991
Neuroanatomical studies on the distribution of corticotropin-releasing hormone (CRH) and its receptors (7) as well as physiological data suggest a regulatory function of endogenous CRH in hypothalamic and extrahypothalamic brain areas [1, 4]. Endogenous CRH acts within the endocrine hypothalamo-pituitary-adrenal axis and affects cardiovascular regulation and respiration through extrahypothalamic pathways. CRH also stimulates gluconeogenesis and release of plasma-catecholamines. Our experiments in humans also demonstrate an influence on respiration and on heart rate activity after systemic application of CRH. Respiratory parameters and heart rate were analyzed during steady-state conditions …