Search results for "Endogeny"
showing 10 items of 147 documents
Lack of correlation between expression of HIF-1alpha protein and oxygenation status in identical tissue areas of squamous cell carcinomas of the uter…
2004
Abstract Hypoxia inducible factor-1α (HIF-1α) has been proposed as a candidate endogenous marker of tumor hypoxia and as a molecular mediator of hypoxia-driven malignant progression and acquired treatment resistance. In this study, HIF-1α expression in 68 biopsies of oxygenation measurement tracks from squamous cell carcinomas of the uterine cervix of 38 patients was assessed. Expression of HIF-1α was commonly found to increase as a function of distance from microvessels, at the center of tumor cell aggregations, and in the vicinity of necrotic areas. However, there was no correlation of HIF-1α expression with median oxygen tension (oxygen partial pressure; pO2) and hypoxic fractions (hypox…
Habituation of the orienting response as reflected by the skin conductance response and by endogenous event-related brain potentials
2004
The paper is concerned with the question of whether endogenous components of the auditory event-related brain potential (ERP) qualify for showing habituation of the orienting response (OR). Although response decrements have been found in nearly every ERP component, this question is still of current concern because a true selective response inhibition proving habituation of the OR is still lacking. The question has been tackled using single-trial ERP measurements in classical variants of the repetition/change paradigm commonly used in the traditional OR research on autonomous responses such as the skin conductance response (SCR). Results on 120 adults indicate that at least two endogenous co…
Effects of Some Guanidino Compounds on Human Cerebral Arteries
1999
Background and Purpose —Accumulation of endogenous guanidino-substituted analogues of l -arginine in chronic renal failure might contribute to some of the vascular and neurological disorders of this pathology. We tested the hypothesis that in human cerebral arteries, some guanidino compounds may increase vascular tone, through nitric oxide (NO) synthase inhibition, and impair endothelium-dependent relaxation. Methods —Rings of human middle cerebral artery were obtained during autopsy of 26 patients who had died 3 to 12 hours before. The rings were suspended in organ baths for isometric recording of tension. We then studied the responses to N G -monomethyl- l -arginine (L-NMMA), N G , N G -…
Exogenous and endogenous provocation of psoriasis. A contribution to the Koebner phenomenon.
1974
Previous literature reports as well as own investigations concerning exogenously and endogenously induced Koebner-reactions in psoriatics are presented. The time interval between irritation and the Koebner-reaction is emphasized. It is proposed, that the intensity of the psoriatic reaction is mediated by circulating DHEA-deficiency. Hypothetical models are presented which allow to explain the different developmental rates of psoriatic lesions in relation to the type of irritation, the area affected and the subsequent proliferative responses.
Detection of γ‐hydroxybutyric acid‐related acids in blood plasma and urine: Extending the detection window of an exogenous γ‐hydroxybutyric acid inta…
2021
In crimes facilitated by γ-hydroxybutyric acid (GHB) administration, the frequent occurrence of anterograde amnesia of the victims as well as the short detection window and variations of endogenous GHB concentrations complicate obtaining analytical proof of GHB administration. Because elevated endogenous organic acid concentrations have been found in the urine of patients with succinic semialdehyde deficiency (leading to accumulation of GHB in human specimens) and after GHB ingestion, we searched for an alternative way to prove GHB administration via detection of elevated organic acid concentrations in blood plasma and urine. We collected blood and urine samples from narcolepsy patients (n …
Circadian variations in antigen-specific proliferation of human T lymphocytes and correlation to cortisol production.
1995
Cortisol is a well-known immunosuppressant when used therapeutically. The present investigation was set out to study if diurnal variations in endogenous cortisol production are reflected by changes in proliferative responses of human lymphocytes to either a mitogen (phytohemagglutinin-A, PHA) or an antigen (tetanus toxoid, TT) stimulus. The study included eight healthy volunteers. Blood was withdrawn at 0200, 0600, 1000, and 1800h for preparation of lymphocytes and determination of cortisol in plasma. Isolated cells were incubated without (baseline activity) or with inclusion of either 1 micrograms PHA or 10 micrograms TT. Proliferation was measured by labelling with 3H-thymidine for 16 h o…
Endogenous 3-methylhistidine excretion in healthy women and men with reference to muscle protein metabolism.
1984
Presently 3-methylhistidine excretion is widely used for monitoring the metabolic status of patients during different kinds of clinical conditions. Aim of the study was to reconsider its predicative value on the basis of a larger collective of healthy persons and to find a standardization independent from sex. Therefore endogenous 3-methylhistidine release of 40 healthy adults (24 women and 16 men) was measured and related to body weight, body surface area, arm muscle circumference, and nitrogen and creatinine excretion. A positive correlation could be observed only for 3-methylhistidine and creatinine excretion and that to the same extent both for females and males. Assuming that the excre…
Influence of the ovary on parameters of LH secretion during the recovery from buserelin-induced desensitization
1994
Abstract This study examined the effect of the ovary on LH pulsatility and on the secretory performance of gonadotrophes during the phase of recovery after treatment with buserelin, a GnRH analogue. We included 12 patients, who received buserelin (1.2 mg/day, intranasally for 3 months) as a reductive therapy for uterine leiomyomatosis prior to hysterectomy. Six patients were oophorectomized and the other 6 patients had their ovaries preserved. LH was measured in samples taken basally up to 36 days after suppression of buserelin. LH pulsatility was studied on day 9 along a 24-h cycle, and the response of the hormone to a double-stimulus GnRH test on days 0, 9, 20, and 34. The concentration o…
LRP1 mediates bidirectional transcytosis of amyloid-β across the blood-brain barrier.
2011
According to the "amyloid hypothesis", the amyloid-β (Aβ) peptide is the toxic intermediate driving Alzheimer's disease (AD) pathogenesis. Recent evidence suggests that the low density lipoprotein receptor-related protein 1 (LRP1) transcytoses Aβ out of the brain across the blood-brain barrier (BBB). To provide genetic evidence for LRP1-mediated transcytosis of Aβ across the BBB we analyzed Aβ transcytosis across primary mouse brain capillary endothelial cells (pMBCECs) derived from wild-type and LRP1 knock-in mice. Here, we show that pMBCECs in vitro express functionally active LRP1. Moreover, we demonstrate that LRP1 mediates transcytosis of [(125)I]-Aβ(1-40) across pMBCECs in both direct…
LXR antagonists induce ABCD2 expression
2014
X-linked adrenoleukodystrophy (X-ALD) is a rare neurodegenerative disorder characterized by the accumulation of very-long-chain fatty acids resulting from a beta-oxidation defect. Oxidative stress and inflammation are also key components of the pathogenesis. X-ALD is caused by mutations in the ABCDI gene, which encodes for a peroxisomal half ABC transporter predicted to participate in the entry of VLCFA-CoA into the peroxisome, the unique site of their beta-oxidation. Two homologous peroxisomal ABC transporters, ABCD2 and ABCD3 have been proven to compensate for ABCD1 deficiency when overexpressed. Pharmacological induction of these target genes could therefore represent an alternative ther…