19 research outputs found
Mathematical model of thermal operation of eontinuous furnace of mill 2250 of Alchevsk metallurgical industrial complex in coupled production
Using the developed mathematical model of coupled (external and internal) head exchange, allowing for the form and thermoprocessing peculiarities of the continuous pusher- type furnace, there are improved the temperature-thermal conditions of slabs heating in furnace of mill 2250 of Alchevsk metallurgical industrial complex
Calculation and experimental studies of the technology of heating steel billets in pusher furnaces
The article gives analytical solution to the problem of nonsymmetric heating of blooms in continuous furnaces based on the '‘equivalent sources method’'. Parametrical identification by the results of industrial experiments has shown sufficient accuracy and reliability of the method
Problem of conjugated heating of steel bloom in pusher-type multistage continuous furnace of the mill 600
А mathematical model and an algorithm of calculation of conjugated heat-exchange while heating metal castings in a pusher-type continuous furnace. The approach is fonnulated to the problem of calculation area quantization at setting forth conjugated problems of radiation-conductive heat exchange for geometric form heating furnaces
Development of heating regimes of non-solidified ingots with mass 9,45-13,9 t in the regenerative fountains of the blooming department of ОАО "Alchevski metallurgical industrial complex"
The mechanism of heating of ingots with liquid heart, providing the increase of productivity and decrease of discharge intensity of standard coal, is investigated on the basis of mathematical modelling of the processes of solidification, cooling and heating of coarse blooming ingots as a unified combined heat technological process
Combined estrogenic and anti-estrogenic properties of estetrol on breast cancer may provide a safe therapeutic window for the treatment of menopausal symptoms
Increased risk of breast cancer is a critical side effect associated with the use of a menopausal hormone therapy (MHT). Estetrol (E4) is a natural estrogen produced by the human fetal liver and is a promising compound for clinical use in MHT. However, its impact on breast cancer is controversial and poorly defined. In this preclinical study, we show that E4 acts as a weak estrogen by stimulating the growth of hormone-dependent breast cancer only at concentrations exceeding menopausal therapeutic needs. E4 presents also an antitumor activity by decreasing the strong proliferative effect of estradiol (E2). While estrogen receptor alpha (ERα) is the predominant receptor mediating its effects, the dual weak-estrogenic/anti-estrogenic feature of E4 results from differential signaling pathways activation. Both nuclear and rapid extra-nuclear signaling pathway are necessary for a complete estrogenic effect of E4. However, the antitumor action of E4 is not due to a capacity to antagonize E2-induced nuclear activity. Altogether, our results highlight that E4 has a limited impact on breast cancer and may offer a safe therapeutic window for the treatment of menopausal symptoms.This work was supported by grants from the Fonds de la Recherche Scientifique - FNRS (F.R.S.-FNRS,
Belgium) : FRSM 3.4557.12, FRSM 3.4567.11, Télévie 7.4524.11, Télévie 7.4604.13 ; the Fonds spéciaux de la Recherche (University of Liège) : FSRC- 12/64, FSRC-12/92, FSRC-14/89, FSRC-14/65, FSRC-14/109, FSRC-14/62 ; the Centre Anticancéreux près l’ Université de Liège, the Fonds Léon Fredericq (University of Liège), the Direction Générale Opérationnelle de l’Economie, de l’Emploi et de la Recherche from the Service Public de Wallonie (DGO6, SPW, Belgium) ; the Interuniversity
Attraction Poles Programme - Belgian Science Policy (Brussels, Belgium) : IAP Phase VII - P7/03 ; the Plan National Cancer (Service Public Fédéral) and the Actions de Recherche Concertées (University of Liege, Belgium): A.R.C. 11/16-02
Analysis of temperature state of massive flat ingot in conditions of radiational contraflow
There is given the analysis of the task solution of counterflow heat exchange at heating of solids of classic form taking into account non-linearities of I and II type. As a mathematical apparatus there is used “the method of equivalent sources of energy”
Relationship between human tumor-associated antigen RCAS1 and gestational diabetes mellitus.
PROBLEM: The human tumor-associated receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is considered to play a role in the inhibition of the maternal immune response during pregnancy. The aim of our study was to investigate the expression of RCAS1 protein in the placenta and to compare its concentration in maternal and cord blood sera between normal pregnancies and pregnancies complicated by gestational diabetes mellitus (GDM). METHOD OF STUDY: Samples were obtained from women with GDM (n = 8), women with type 1 DM (n = 5), and healthy term controls (n = 27) after delivery. Placentas were studied by immunohistochemistry, and real-time polymerase chain reaction. For assessment of RCAS1 concentrations in maternal and cord blood sera, enzyme-linked immunosorbent assay was performed. RESULTS: The RCAS1 protein mRNA expression in the placentas of patients with GDM was significantly lower than that in the controls (P = 0.005). The maternal blood RCAS1 protein concentration of the GDM cases was also significantly lower than that in the controls (P = 0.0411), whereas the cord blood RCAS1 protein concentration was significantly higher in the GDM and type 1 DM groups than in the controls (P = 0.0311 and P = 0.0192, respectively). CONCLUSION: The present results suggest that RCAS1 protein might have an important role in the development of GDM
Analysis of RCAS1 Immunoreactivity within Hydatidiform Mole Cells and Decidual Cells according to the Applied Therapeutic Strategy: Surgery or Surgery Followed by Chemotherapy
Effects of 4-Hydroxy-2-Nonenal, a Major Lipid Peroxidation-Derived Aldehyde, and N-Acetylcysteine on the Cyclooxygenase-2 Expression in Human Uterine Myometrium.
Background: Chorioamnionitis is one of the important causes of preterm labor. Preterm labor with chorioamnionitis is associated with oxidative stress. We reported that 4-hydroxy-2-nonenal (4-HNE), a major end product of oxidative fatty acid metabolism, is accumulated in the placenta with chorioamnionitis. The aim of this study was to confirm the effect of 4-HNE on cyclooxygenase-2 (COX-2) and prostaglandin (PG) induction in the uterine myometrial tissues. We also examined the effect of N-acetylcysteine (NAC) on 4-HNE-induced COX-2 expression. Methods: Uterine myometrial tissues were obtained from 5 patients. One of them underwent elective cesarean section without labor, and 4 of them underwent hysterectomy because of placental previa or atonic bleeding. We stimulated the uterine myometrial tissues with 4-HNE. In addition, the tissues were pretreated with NAC before 4-HNE treatment. The expression of COX-2 mRNA was observed by real-time PCR. PGE2 and prostacyclin release into the supernatants of the tissue cultures was measured by ELISA. Results: 4-HNE induced the COX-2 mRNA expression and PGE2 production in the uterine myometrial tissue culture in a dose-dependent and time-dependent manner. NAC inhibited 4-HNE-induced COX-2 expression. Conclusion: 4-HNE may play an important role in preterm labor. NAC might be protective against preterm labor under oxidative stress
Oxidative stress-induced S100B protein from placenta and amnion affects soluble Endoglin release from endothelial cells.
Oxidative stress with elevated intracellular Ca(2+) concentration as well as endothelial dysfunction is a component of pre-eclampsia. Our aim was to investigate the oxidative stress-dependent expression of Endoglin and Ca(2+)-binding S100B protein from villous and amniotic tissue cultures, and to assess sEng expression from S100B protein-stimulated endothelial cells. We initially examined Endoglin and Hydroxy-nonenal-(HNE)-modified proteins in the placentas and amnion obtained from women with pre-eclampsia (n = 8), and healthy controls (n = 8) by immunohistochemistry. To examine oxidative stress and the S100B protein effect on sEng expression from endothelial cells, normal villous and amniotic tissue cultures were stimulated by 4-HNE, sodium fluoride and xanthine/xanthine oxidase, whereas human umbilical vein endothelial cell cultures were treated with S100B protein in a dose- and time-dependent manner at 37 degrees C in an environment of 95% air and 5% of CO(2). Culture supernatants were assessed using ELISA. Cell viability was determined using MTS assay. The concentrations of sEng and S100B protein were significantly increased in the villous and amniotic tissue culture supernatants under oxidative stress. S100B protein-stimulated endothelial cells released sEng into conditioned media with a significantly higher expression levels at a concentration of 200 pM-20 nM S100B by 2 h, whereas treated with 200 nM of S100B endothelial cells significantly expressed sEng by 12 h and stimulated the cell proliferation by the same period of time. Our findings show that oxidative stress affects sEng and S100B protein expression from villous and amniotic tissues, and picomolar and low nanomolar concentrations of S100B protein significantly up-regulate sEng release from endothelial cells leading to endothelial dysfunction