620 research outputs found
Effects of estradiol-17 beta, testosterone and a black cohosh preparation on bone and prostate in orchidectomized rats
No full textEstradiol (E,) and testosterone(T) effectively prevent orchidectomy (orx) induced osteoporosis. T, however, Stimulates prostate proliferation which may lead to malignancy. We showed that a Cimicifuga racemosa (CR) preparation had bone-sparing effects without exerting estrogenic effects in the uterus. We Studied therefore whether a CR preparation has also antiosteoporotic effects in orx rats substituted with E-2, T or CR via pelleted food over a period of 3 months. Average daily intake per animal was: T: 25 mg; E-2: 0.325 mg, CR low close: 33 CR high dose: 133 mg, E-2 T and CR a, the high dose partially prevented development of osteoporosis as measured by quantitative computer tomography in the metaphysis of the tibia. E-2, but not T or CR reduced serum osteocalcin and the metabolic products of collagen-1 alpha 1. Gene expression of collagen-1 alpha 1 and tartrate-resistant acid phosphatase was decreased by E-2 and the higher dose of the CR extract but increased in the T-treated animals. In the prostate T inhibited androgen receptor, estrogen receptor alpha and insulin-like growth factor-1 gene expression but Stimulated the expression of the ERP gene. These effects were not shared by E-2 or both doses of the CR extract. It is concluded that E-2 T and CR exert antiosteoporotic effects in the metaphysis of the tibia of orx rats. T has profound effects in the prostate which were not seen in the E-2- and CR-treated animals. Therefore, the Cimicifuga racemosa extract BNO 1055 may be useful to prevent osteoporosis in aged male patients with reduced testosterone production. (c) 2004 Elsevier Ireland Ltd. All rights reserved
Kunstgeschichte und Philologie Methodisch-Kritisches zu Forschungen über Peter Vischer d. Ä. und seine Söhne
No full textThe Tombs of the Caliphs
No full textback: "C. Wuttke: Gräber der Kalifen -- The tombs of the caliphs - Les Tombeaux des Califes : R130. R. & J. D."Reproduction of an oil painting of two tombs at sundow
Properties of the Urinary Bladder Wall and their Modulation by Estradiol and Raloxifene in a Rat Model
No full textObjectives: Urinary incontinence is a common symptom of urogenital aging that affects a considerable proportion of postmenopausal women. Morphological and morphometrical modulation of the bladder by estrogen are known. Yet data showing that this translates into changes of in vivo function of the urinary bladder are missing. Methods: We measured urodynamic parameters in anaesthetized, surviving rats. Following ovariectomy animals were divided into three groups and fed either an estradiol-, raloxifene-, or unsupplemented soy-free formula for ten weeks. Via a transurethral catheter the intravesical pressure was recorded during a stretch period (the urinary bladder was filled), and a one-minute isometric accommodation period immediately after the filling period. Upon termination of the experiment upper and lower halves of the bladder were processed histologically. Results: The estrogen-, and raloxifene-treated animals showed significantly higher pressures in responses to rapid stretch. Bladder compliance during the isometric period on the other hand was not significantly affected by these treatments. Thickness of the epithelial layer, collagen content and muscle bundles were significantly increased by estrogen and raloxifene treatment. Conclusions: This is a good animal model to investigate modulation of detrusor muscle contractility and stiffness. Both estradiol and raloxifene increase bladder contractility. Urinary bladder morphology indicates that estrogen acts primarily in the upper half of this organ since significant effects on collagen content and muscle fibers are only found in this part
Effects of isoflavonoids and other plant-derived compounds on the hypothalamus–pituitary–thyroid hormone axis
No full textObjectives: There is increasing concern that exposure to flavonoids may lead to endocrine disruption of the hypothalamus-pituitary-thyroid hormone axis, and, additionally, there is evidence that secondary plant metabolites contained in our daily diet or used for hormone-replacement therapy act as hormones themselves, similar to known isoflavonoid effects in the steroid hormone network. These compounds of natural origin affect the thyroid hormone feedback system by interference with different components of this homeostatically regulated system: biosynthesis, secretion and metabolism, transport, distribution, and action of thyroid hormones including the feedback mechanism. Genistein and daidzein, the major components of soy, influence thyroid hormone synthesis by inhibition of the iodide oxidizing enzyme thyroperoxidase, interfere with thyroid hormone transport proteins and 5'-deiodinase type I activities in peripheral tissues, which leads to altered thyroid hormone action at the cellular level. Synthetic flavonoids, such as F21388, structurally similar to thyroxine, cross the placenta and reach the fetal brain of animal models also. Methods: A review of effects of various isoflavonoids and plant-derived extracts on the hypothalamus-pituitary-thyroid axis is the major objective of this contribution. In addition, new experimental data obtained in ovariectomized (ovx) rats will be presented. The substances tested here were plant extracts of Agnus castus, Belamcanda chinensis, Silybum marianum, Cimicifuga racemosa, and a commercially available soy product. Results: In ovx rats the extract at two doses showed no effects on circulating TSH and thyroid hormone serum levels after 3 months of treatment. Conclusion: The thyroid hormone network has a considerable capacity to compensate for disturbances of this feedback system as it is necessary for various metabolic and catabolic reactions and development. With respect to still insufficient nutritive iodine-supply of almost one third of the world population, possible adverse flavonoid actions on the thyroid hormone axis have to be examined more closely. (c) 2006 Elsevier Ireland Ltd. All rights reserved
Numerical analysis of thermal cycling during a multi-stage energy pile thermal response test
No full textEnergy piles are emerging as convenient alternative to the more traditional borehole heat exchangers (BHEs) to provide heating/cooling to buildings, as they remove the need for special purpose excavations and can accommodate more pipes, thus enhancing energy performance. However, their different aspect ratio compared to BHEs requires different modelling tools and dedicated thermal response testing, to achieve adequate thermal design. In this work, the results of an extended multi-stage thermal response test (TRT) carried out on a single energy pile installed in London Clay are presented in terms of both fluid temperature data and concrete temperature, measured by vibrating wire strain gauges and optic fibre sensors. The results are then explored in detail by means of a finite element numerical code, able to account for both convective heat exchange in the fluid, between the fluid and the solids and transient heat diffusion in the concrete and the ground. Analysis of the TRT field data shows that during the later stages of the test there is clear evidence of cyclic changes in performance. Investigation of these effects using the numerical model raises the possibility that there could be some alteration of the properties of the soil-pile contact during the test. Hypotheses for the observed behaviour are tentatively put forward and discussed with work recommended to further investigate the percieved phenomena
Competition and Development in Automotive Global Value Chains: Insights from Thailand, South Africa and Argentina
No full textThis article examines the varying outcomes of countries participating in the automotive global value chain (GVC), focusing on Thailand, South Africa, and Argentina. While all three countries had similar starting points in the 1990s, Thailand outperformed the others by achieving greater scale in vehicle production, leading to significant local economic benefits, such as trade surpluses, expanded supply chains, and the localization of R&D activities. The paper introduces the concept of the ‘adding-up problem’ in automotive GVC participation, where lead firms centralize production and R&D to maximize economies of scale, leaving competing countries with limited production volumes and weaker local supply chains. Based on more than 100 semi-structured interviews, along with industry statistics, this study compares the automotive industries of the three countries, focusing on their competition in medium-sized pickup truck production. The paper contributes to GVC literature by refining the understanding of zero-sum dynamics in global production. We demonstrate that countries’ success is constrained by the relational nature of GVC competition, but show that the automotive GVC nonetheless offers substantial economic development benefits for participating countries. Thailand’s superior performance is explained through serendipitous factors like income level and location, as well as first-mover advantages due to strategic industrial policies
Phytoestrogen resveratrol suppresses steroidogenesis by rat adrenocortical cells by inhibiting cytochrome P450 c21-hydroxylase
No full textBackground and Aim: The phytoestrogen resveratrol is found in grapes, mulberries and peanuts, all of which are consumed regularly by humans. Resveratrol is also used in chemotherapy against cancer and aging and as a cardioprotectant. The aim of the present study was to characterize the effects of resveratrol on rat adrenal steroidogenesis and to study the underlying mechanism. Methods: Adrenocortical cells were isolated from the adrenal glands of normal male rats ( in vitro) and from male rats administered resveratrol in their diet for 12 weeks ( ex vivo). Cells from resveratrol-treated and non-treated rats were tested ex vivo for responsiveness to ACTH and cells from normal rats were tested in vitro for responsiveness to ACTH in the presence and absence of resveratrol. Corticosterone and progesterone production were measured by RIA and expression of steroidogenic enzymes analyzed by PAGE/Western blotting. Results: Corticosterone production was inhibited 47% by 50 mu M resveratrol in vitro and 20% ex vivo, while progesterone production was elevated to 400% of the control value in in vitro experiments. Resveratrol treatment decreased adrenal cytochrome P450 c21-hydroxylase expression in vivo and cell culture conditions. No changes in cell viability or morphology were caused by exposure to resveratrol in both ex vivo and in vitro experiments. Conclusion: Resveratrol suppresses corticosterone production by primary rat adrenocortical cell cultures in vitro and ex vivo by inhibiting cytochrome P450 c21-hydroxylase. Copyright (c) 2005 S. Karger AG, Basel
Text-fig. 1. a: Map of France showing geographic position of Saint-Bauzile (source: http://d-maps.com/m/europa/france/france/ france09.gif). b: Overview of the active diatomite quarry at the Montagne d'Andance, photograph taken in 2017. c: SEM image of a frustule of pennate diatom (cf. Navicula sp.) from Saint-Bauzile. d) SEM image of frustules forming a colony of centric diatoms (cf. Diatoma sp.) from Saint-Bauzile. in Evidence For Wildfires During Deposition Of The Late Miocene Diatomites Of The Konservat-Lagerstätte Lake Saint-Bauzile (Ardèche, France) - Preliminary Results
No full textText-fig. 1. a: Map of France showing geographic position of Saint-Bauzile (source: http://d-maps.com/m/europa/france/france/ france09.gif). b: Overview of the active diatomite quarry at the Montagne d'Andance, photograph taken in 2017. c: SEM image of a frustule of pennate diatom (cf. Navicula sp.) from Saint-Bauzile. d) SEM image of frustules forming a colony of centric diatoms (cf. Diatoma sp.) from Saint-Bauzile.Published as part of Uhl, Dieter, Jasper, Andre & Wuttke, Michael, 2022, Evidence For Wildfires During Deposition Of The Late Miocene Diatomites Of The Konservat-Lagerstätte Lake Saint-Bauzile (Ardèche, France) - Preliminary Results, pp. 329-340 in Fossil Imprint 78 (1) on page 331, DOI: 10.37520/fi.2022.014, http://zenodo.org/record/716783
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