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1.
S Cupisti R Dittrich H Binder N Kajaia I Hoffmann T Maltaris M W Beckmann A Mueller 《Experimental and clinical endocrinology & diabetes》2007,115(6):380-386
There is growing evidence that obesity in women lead to a more severe form of hyperandrogenism and other endocrine abnormalities which may have some health implications later in life. Obese females are at higher risk for metabolic syndrome due to severe hyperandrogenemia. Calculated values for free testosterone are equivalent to those obtained by equilibrium dialysis, which is one of the reference measurement procedures (RMP) for estimation of free testosterone and may be capable of replacing values estimated using RMP's. For adult women correlations of body mass index (BMI) with calculated free (cFT) and bioavailable testosterone (cBT) are still rare, while these data are reported for peripubertal and adolescent girls. In this study we aimed to investigate the association between BMI and different androgen parameters (including calculated free and bioavailable testosterone, free androgen index, and sex hormone-binding globulin [SHBG]) in adult women with Hirsutism and with PCOS. In hirsute women with BMI > or = 25 kg/m2 measured total testosterone (TT) was significantly higher, SHBG was significantly lower and the calculated androgen parameter (FAI, cFT and cBT) were significantly higher compared to women with BMI < 25 kg/m2. In PCOS women with BMI > or = 25 kg/m2 TT was significantly higher, SHBG was significantly lower and the calculated androgen parameter (FAI, cFT and cBT) were also significantly higher compared to women with BMI < 25 kg/m2. In both the Hirsutism and PCOS-group there was a positive correlation between BMI and TT, cFT, and cBT, while BMI was negatively correlated with SHBG. In summary, in adult women with Hirsutism and PCOS obesity is associated with increased levels of TT and decreased levels of SHBG resulting in significant elevated calculated free and bioavailable testosterone levels. Obesity might lead to a more severe form of hyperandrogenism with elevated calculated free and bioavailable testosterone in the study population. 相似文献
2.
Tumor necrosis factor-alpha in whole blood cultures of preeclamptic patients and healthy pregnant and nonpregnant women. 总被引:4,自引:0,他引:4
Ilse Beckmann Shlomo Ben Efraim Monica Vervoort Wil Visser Henk C S Wallenburg 《Hypertension in pregnancy》2004,23(3):319-329
OBJECTIVES: Tumor necrosis factor-alpha (TNF-alpha) is recognized as a likely mediator of the excessive endothelial activation and injury that is a key pathogenetic mechanism of preeclampsia. We used whole blood cell cultures from 12 patients with severe preeclampsia and from 12 healthy pregnant and nonpregnant women to determine the release of TNF-alpha by unstimulated leukocytes as a measure of their state of activation, and their response to stimulation with lipopolysaccharide (LPS) as an indicator of their state of priming. METHODS: Blood was cultivated without and with LPS, and TNF-alpha release was measured after six and 24 hours of cultivation by enzyme-linked immunoassays. Differential leukocyte counts were performed, and TNF-alpha values calculated per 10(5) monocytes. RESULTS: In unstimulated whole blood cultures, TNF-alpha release after six hours of cultivation was similar in all three groups; but after 24 hours, TNF-alpha concentrations in culture supernatants from preeclamptic patients were significantly higher than were values obtained in blood from normotensive pregnant women. In LPS-stimulated blood cultures with a maximum of TNF-alpha release at six hours cultivation time, TNF-alpha concentrations were significantly lower in preeclamptic women than they were in both control groups. We showed in an additional experiment that a strong LPS challenge following preactivation with high doses of LPS resulted in reduced release of TNF-alpha compared with release of TNF-alpha following preactivation with low doses of LPS. CONCLUSIONS: The observed high capacity for spontaneous TNF-alpha release by leukocytes in preeclampsia indicates activation of TNF-alpha producing leukocytes by the disease process. Preactivation and exhaustion of leukocytes by leakage of TNF-alpha could lead to the reduced response to TNF-alpha inducer LPS as observed in blood cultures from preeclamptic patients. 相似文献
3.
4.
The birthrates of 507 schizophrenic patients with high familial loading were compared to the general population. The patient group showed a clearcut decrease in births within a defined winter and spring period. In particular, this was obvious if Leonhard's classification of schizophrenia was applied. The hypothesis is proposed that, in some fetuses at high genetic risk for schizophrenia, an exaggerated level of abortions or stillbirths occurs if additional environmental noxious agents are present in a crucial period of brain maturation. Pertinent evidence in support of this is found in literature. 相似文献
5.
6.
W Würfel M W Beckmann R Austin U Herzog P J Albert 《Gynecologic and obstetric investigation》1992,33(3):129-133
We studied the influence of human prolactin on the secretion and de novo synthesis of human chorionic gonadotropin (hCG) in the human term placenta in culture. Placental tissue from 14 patients with uncomplicated pregnancies and deliveries was prepared mechanically, with addition of a Percoll gradient step. hCG levels were determined in the culture media and in the cytosolic fraction of cells by means of an enzyme immunoassay with coated beads. The amount of newly synthesized hCG was measured by the extent of incorporation of 35S-methionine into the hCG molecule. Our results showed that human prolactin had two different effects in vitro: between 1/2 and 1 h, prolactin slightly increased secretion of hCG into the culture medium without affecting de novo synthesis; after 2 h, prolactin began to cause a significant decrease in both secretion and de novo synthesis of hCG over several hours. It appears that both effects are receptor mediated, for ovine prolactin failed to produce any response. We conclude that prolactin is one of the main factors regulating the synthesis and secretion of hCG in the human trophoblast at term. 相似文献
7.
I Richard O Broux D Hillaire D Cherif F Fougerousse D Cohen J S Beckmann 《Human molecular genetics》1992,1(8):621-624
Limb-Girdle Muscular Dystrophy (LGMD) is a myopathy with clinical and transmission heterogeneity. The recessive form, LGMD2, has been recently mapped by linkage analysis to 15q. As an attempt to identify the gene involved in this pathology, we tested as candidate gene the LD locus, called LD for limb deformity. This gene has recently been identified and mapped to chromosome 15q13-q14. It is homologous to the murine formin gene which is localized to mouse chromosome 2. Mutations in this murine gene have been shown to cause limb deformity and kidney defect. YAC clones containing the LD gene were isolated and utilised to confirm the cytogenetic localisation. Internal DNA polymorphisms of the LD locus were analyzed in LGMD2 and CEPH families. The LD gene was mapped between the alpha cardiac actin gene and the D15S24 locus. Crossovers between the LGMD2 and the LD loci excluded the LD gene as a candidate for LGMD2. 相似文献
8.
Zum Thema
Die Steroidhormone, ?strogene und Gestagene, vermitteln ihre organspezifische Funktion zumeist über Steroidhormonrezeptoren.
Nach Bindung des Ligand-Rezeptor-Komplexes wird u. a. die Mitoserate gesteigert und steroidhormonabh?ngige Gene stimuliert.
Steroidhormonrezeptoren werden ubiquit?r in der Mamma, dem Endometrium etc. exprimiert, so da? das steroidhormonvermittelte
Signal in diesen Organen ausgeführt werden kann. Parallel zur steroidhormonvermittelten Signalkette werden physiologische
Zellfunktionen einschlie?lich Zellproliferation zus?tzlich von Protoonkogenen und Tumorsuppressorgenen reguliert. Physiologische
Interaktionen zwischen den unterschiedlichen Signalketten bzw. Fehlregulationen in einem oder mehrere dieser Systeme sind
Schlüsselschritte zur malignen Transformation von Zellen. Trotz vorhandener Steroidhormonrezeptorexpression wird nicht immer
die Funktion des Steroidhormons bzw. bei therapeutischem Einsatz die des Steroidhormonantagonisten vermittelt. Patientinnen
mit Mammakarzinom sprechen zumeist auf eine Hormontherapie mit Tamoxifen an, wohingegen Patientinnen mit Endometriumkarzinom
nur sehr selten auf diese Therapie ansprechen. Zus?tzlich induziert Tamoxifen Endometriumkarzinome. Diese Befunde lassen auf
organspezifische, regulative Kofaktoren des Steroidhormonrezeptors und seiner Wirkung schlie?en. Der therapeutische Einsatz
von Hormonen im Rahmen einer Hormonersatztherapie zeigt keine wesentliche Risikoerh?hung für die Entstehung eines Mamma- oder
Ovarialkarzinoms, bei Kombinationstherapien auch nicht für die Entstehung eines Endometriumkarzinoms. In der Diskussion ist
derzeit der Einsatz der Hormonersatztherapie bei Patientinnen mit Zustand nach Mamma- oder Endometriumkarzinom. 相似文献
9.
Panizzutti R Rausch M Zurbrügg S Baumann D Beckmann N Rudin M 《Neuroscience letters》2005,380(1-2):111-115
d-Serine has been proposed as an endogenous modulator at the co-agonist glycine-binding site of N-methyl-d-aspartate (NMDA) receptors. There is still some debate as to whether this site is saturated in vivo, but it seems likely that this depends on regional differences in local glycine or d-serine concentrations. In order to identify areas where the co-agonist site was not fully activated in vivo, we studied the effect of intraperitoneal d-serine administration in the rat brain using functional magnetic resonance imaging (fMRI). Using contrast agent injection, the variations in the relative cerebral blood volume (CBVrel) in several regions of interest were evaluated. d-Serine (50 mg/kg) elicited a significant statistical increase in the CBVrel in the hippocampus. This effect was inhibited by the specific full antagonist of the co-agonist glycine site L-701,324 indicating that the hippocampal activation occurred through the binding of the agonist d-serine to the glycine-binding site of NMDA receptors. This result demonstrates that in the hippocampus, the co-agonist sites of NMDA receptors are not endogenously saturated under our experimental conditions, suggesting an important role of d-serine in the modulation of receptor function in the hippocampus. 相似文献
10.
A novel role for shuttling SR proteins in mRNA translation 总被引:15,自引:1,他引:15