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11.
Magdy S. Aly Paola Dal Cin Herman Van Den Berghe Wim Van De Voorde Hein Van Poppel Filip Ameye Luc Baert 《Genes, chromosomes & cancer》1994,9(4):227-233
We combined conventional cytogenetic analysis and fluorescence in situ hybridization of short-term cultures of 28 samples from benign prostatic hyperplasia. Lou of the Y chromosome was the most common chromosome change, followed by trisomy 7. Trisomy 7, however, may be unrelated to the origin of benign prostate hyperplasia, in which the only and not very specific change seems to be the loss of the Y chromosome. Genes Chrom Cancer 9:227-233 (1594). © 1994 Wiley-Liss, Inc. 相似文献
12.
Stem cells exhibit unique properties and hold high therapeutic promise, but factors influencing their differentiation after transplantation need to be recognized and defined for this promise to be fully met. Here, we demonstrate that endogenous colony-forming unit spleen (CFU-S) colonies are not generated in lethally irradiated mice transplanted with neural stem cells obtained from brain tissue of syngeneic donors. We investigated the proportion of transplanted neural stem cells that contributed to hematopoietic reconstitution and compared the distribution of transplanted cells in nonsplenectomized to that of splenectomized mice following sublethal whole-body irradiation. We also used clonogenic assays, colony assays, and histochemical analyses to explore conditions under which transplanted, beta-galactosidase-tagged neural stem cells underwent hematopoietic differentiation. Our results suggest that neural stem cells do undergo extramedullary hematopoiesis, even while no endogenous hematopoietic colonies develop in the spleen. Furthermore, we found that neural stem cells effectively colonized the bone marrow of splectomized recipients. We conclude that the hematopoietic differentiation of neural stem cells is highly dependent on the extramedullary environment. We also conclude that the bone marrow does not provide an environment supportive of hematopoietic differentiation by neural stem cells. 相似文献
13.
Swirski FK Gajewska BU Robbins CS D'Sa A Johnson JR Pouladi MA Inman MD Stämpfli MR 《European journal of immunology》2004,34(9):2375-2386
We previously showed that granulocyte-macrophage colony-stimulating factor (GM-CSF) breaks tolerance induction. The objective of this study was to determine whether GM-CSF breaks established inhalation tolerance. To induce tolerance, BALB/c mice were exposed to aerosolized ovalbumin (OVA) for 10 consecutive days. A control group was exposed to saline. Subsequently, tolerant and control animals were exposed to OVA in a GM-CSF-enriched airway microenvironment. Tolerant animals, unlike control animals, did not develop airway and peripheral blood eosinophilia, had diminished levels of OVA-specific IgE, and reduced airway hyper-responsiveness. While tolerant animals did not express IL-4, IL-5 and IL-13, levels of the regulatory cytokines IL-10, IFN-gamma and transfoming growth factor (TGF)-beta were similar between tolerant and non-tolerant animals. Lung CD4+ T cells were activated according to CD69, CD25 and T1/ST2 expression, but systemic responses characterized by splenocyte proliferation and Th2 effector function were dramatically reduced. Concurrent expression of GM-CSF and decorin, a natural inhibitor of TGF-beta, reversed eosinophilic unresponsiveness. Our study suggests that the breakdown of tolerance and, by extension, the emergence of eosinophilic inflammation, requires two signals: one that triggers sensitization and one that interferes with negative regulation. Moreover, our study shows that dysregulated expression of an extracellular matrix protein may break established tolerance and lead to eosinophilic airway inflammation. 相似文献
14.
Marqué S Poirel L Héritier C Brisse S Blasco MD Filip R Coman G Naas T Nordmann P 《Journal of clinical microbiology》2005,43(9):4885-4888
The spread of the plasmid-mediated carbapenem-hydrolyzing oxacillinase OXA-58 was detected in Acinetobacter sp. clinical isolates from southern Europe, the Balkans, and central Turkey. It may contribute significantly to the emergence of carbapenem resistance in Acinetobacter spp., at least in this part of the world. 相似文献
15.
16.
Filip F Brănişteanu D Popovici I Jerca L Topoliceanu F Mancaş G Sărmăşan V Vartolomei M Jerca O Busuioc D 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》1999,103(3-4):153-157
This study aims at assessing the ability of asthma patients to defend themselves against the noxious effects of oxidative stress, known being the inflammatory nature of this disorder. As the anti-radical defence ability of the body is reflected by the antioxidative potential of blood and tissues, our study was based on the determination of the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and CAT/SOD and GPx/SOD ratios in the blood. Except for SOD, the activity of which was lower in asthma patients by -34.08%, CAT and GPx had values increased by +32.18%, respectively, with a resulting increase of CAT/SOD and GPx/SOD ratios. Our data, demonstrating a change in per-oxidants/antioxidants balance in favour of the first ones, seem to suggest that in the treatment of bronchial asthma the association of some compounds with antioxidants effects would be beneficial. 相似文献
17.
Stratone C Ciutea V Filip F Vasilescu L Ciochină AD Căruntu L Stratone A 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》1999,103(3-4):147-152
The nasal haemorrhage is a symptom whose significance is seldom completely investigated. In this paper we present the results that we have obtained in two groups of patients: a pediatric population who presented for repeated episodes of nasal haemorrhage and a group of first trimester pregnant women who also have noticed the appearance of this symptom. Beside the clinical examination, a paraclinical assessment has been performed, which included a laboratory profile (hematology and biochemistry) and electroencephalography (EEG), in which we found significant changes. We conclude that EEG is a valuable investigation technique for diagnosis and monitoring purposes in nasal hemorrhage. Also, the clinical management of the stress-related nasal hemorrhage must address multiple issues for becoming efficient. 相似文献
18.
Filip Vanhoutte Johan Vereecke Edward Carmeliet Norbert Verbeke 《Naunyn-Schmiedeberg's archives of pharmacology》1991,344(6):662-673
Summary Disopyramide, a Class la antiarrhythmic drug, is clinically used as a racemic mixture; R(–)disopyramide and S(+)disopyramide. The major metabolite in man is desisopropyldisopyramide: R(–)desisopropyl-disopyramide and S(+)desisopropyldisopyramide. The effects of the four compounds were compared on the electrophysiological characteristics of the guinea-pig papillary muscle using the standard microelectrode technique. At an external K+ concentration of 5.4 mmol/l and a stimulation frequency of 1 Hz, S(+)disopyramide (20 mol/l) increased action potential duration (APD) by more than 18%, while it was diminished by 6% in the presence of R(–)disopyramide. Resting membrane potential amounted to –87.1 ± 0.5 mV (n = 14) and –85.6 ± 1.2 mV (n = 10), respectively. Also a small but significant difference in effect on the maximal rate of depolarization was observed, R(–)disopyramide being more potent, related with a slower recovery of the maximal rate of depolarization.The enantiomers of the metabolite appeared to be three times less potent than those of the parent drug in their effect on the maximal rate of depolarization. The characteristics of the enantiomers of the metabolite correlated with those of the parent drug: also the R(–)-enantiomer was more potent in decreasing the maximal rate of depolarization and caused more shortening of the action potential than the S(+)enantiomer.Time constants for onset and recovery of/from rate dependent block of the maximal rate of depolarization were dependent upon the external K+ concentration, both for the enantiomers of the parent drug and those of the metabolite. Onset slowed down while recovery accelerated when external K+ was increased. Time constants were lower for the metabolite.When stimulation interval was shortened, the effect on the maximal rate of depolarisation increased. Only for the metabolite statistical significant stereoselective differences were observed at all stimulation intervals. The effects on the action potential duration were dependent upon stimulation interval; for all enantiomers the action potential duration tended to be relatively (% of control) higher at short stimulation intervals than at large stimulation intervals. The effect on the maximal rate of depolarization was also voltage dependent, but no significant differences were observed between the enantiomers, for the parent drug as well as for the metabolite.
Send offprint requests to N. Verbeke at the above address 相似文献
19.
Stratone A Topoliceanu F Driga O Stratone C Filip F Chiruţă R Huceanu C Roguţ V 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2000,104(4):71-74
The cerebral motor and cognitive behavior is obviously altered by chronic alcoholism, which generates significant morphological and biochemical changes. In turn, alcoholic withdrawal improves the cerebral blood supply, the psychological and motor behavior and the EEG appearance, especially in young alcoholics. Our study also underlines that alcoholic women develop a late improvement of the clinical and bioelectrical condition during the alcoholic withdrawal. 相似文献
20.
Filip Kiekens Ann Debunne Chris Vervaet Lieven Baert Filip Vanhoutte Ivo Van Assche Francois Menard Jean Paul Remon 《European journal of pharmaceutical sciences》2004,22(2-3):117-126
The volume reduction behaviour of powders has been quantified by means of the 'in-die' yield pressure (YP) using Heckel analysis. However, because different YPs are reported for the same material, the experimental conditions influencing this material-constant were investigated. Silicified microcrystalline cellulose was compressed into flat-faced and convex tablets using a compaction simulator instrumented with load and displacement transducers. During compression, upper and lower punch force and displacement data were recorded and corrected for punch deformation. A symmetrical triangle wave compression profile was used and the instantaneous punch velocity was kept constant (5mm/s). Individual tablet height and weight were used for Heckel analysis. The influence of the 'effective compression pressure' (P(EFF)) (ranging from 10 to 350 MPa), punch diameter (PD) (4, 9.5 and 12 mm) and filling depth (FD) (4.5, 7.5 and 10.5mm) on YP was statistically evaluated using Response Surface Modelling software. A quadratic surface response equation, describing the relationship between P(EFF), PD, FD and YP, was proposed for concave (Adj R(2): 0.8424; S.D.: 14.60 MPa) and flat-faced (Adj R(2): 0.8409; S.D.: 4.49 MPa) punches. YP and tensile strength were mainly determined by P(EFF), irrespective of punch curvature. FD and PD had only a minor influence on the YP, although more pronounced for the concave punches. The method used resulted in reproducible P(EFF) and tensile strength values and the flat-faced tablets showed less weight variation. Flat-faced punches are preferred over punches with a concave surface when investigating the volume reduction behaviour of a powder by means of Heckel analysis and the experimental parameters should be reported. 相似文献