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21.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献
22.
23.
Presynaptic short-term depression is maintained during regulation of transmitter release at a GABAergic synapse in rat hippocampus 总被引:1,自引:0,他引:1
Stefan Hefft Udo Kraushaar Jörg R. P. Geiger Peter Jonas 《The Journal of physiology》2002,539(1):201-208
To examine possible interactions between fast depression and modulation of inhibitory synaptic transmission in the hippocampus, we recorded from pairs of synaptically connected basket cells (BCs) and granule cells (GCs) in the dentate gyrus of rat brain slices at 34 °C. Multiple-pulse depression (MPD) was examined in trains of 5 or 10 inhibitory postsynaptic currents (IPSCs) evoked at frequencies of 10–00 Hz under several conditions that inhibit transmitter release: block of voltage-dependent Ca2+ channels by Cd2+ (10 μ m ), activation of γ-amino-butyric acid type B receptors (GABAB Rs) by baclofen (10 μ m ) and activation of muscarinic acetylcholine receptors (mAchRs) by carbachol (2 μ m ). All manipulations led to a substantial inhibition of synaptic transmission, reducing the amplitude of the first IPSC in the train (IPSC1 ) by 72 %, 61 % and 29 %, respectively. However, MPD was largely preserved under these conditions (0.34 in control versus 0.31, 0.50 and 0.47 in the respective conditions at 50 Hz). Similarly, a theta burst stimulation (TBS) protocol reduced IPSC1 by 54 %, but left MPD unchanged (0.40 in control and 0.39 during TBS). Analysis of both fractions of transmission failures and coefficients of variation (CV) of IPSC peak amplitudes suggested that MPD had a presynaptic expression site, independent of release probability. In conclusion, different types of presynaptic modulation of inhibitory synaptic transmission converge on a reduction of synaptic strength, while short-term dynamics are largely unchanged. 相似文献
24.
Induction of a differentiated ciliated cell phenotype in primary cultures of Fallopian tube epithelium 总被引:5,自引:1,他引:5
Human Fallopian tubal epithelial cells in culture lose morphological
features associated with the epithelium in situ and the extent to which
they retain their in-vivo phenotype or function is unknown. In order to
address this question, immunocytochemical markers were identified which
distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+)
epithelial cells in tissue sections of Fallopian tube. These markers were
used to analyse the phenotype of tubal cells in vitro. Primary cultures of
human tubal epithelial cells were seeded onto glass and grown to confluence
before addition of oestradiol-17beta. In the absence of hormone, tubal
epithelial cells expressed cytokeratins and nuclear receptors for oestrogen
and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell
phenotype. Following the addition of oestradiol-17beta, a proportion of
cells became positive for LhS28. The induction of a ciliated epithelial
cell phenotype was confirmed by scanning electron microscopy, where on
permeable collagen membranes, approximately one-third of tubal epithelial
cells became ciliated in the presence of oestradiol-17beta. We suggest that
in vitro, tubal epithelial cells adopt an immature secretory-like phenotype
and that oestrogen can induce differentiation to a ciliated epithelial cell
phenotype.
相似文献
25.
Matthias Wicklmayr Günther Dietze Bernulf Günther Richard Schifmann Ingolf Böttger Reinhard Geiger Hans Fritz Hellmut Mehnert 《Inflammation research》1980,10(4):339-343
The influence of synthetic bradykinin (BK) on disturbed protein and carbohydrate metabolism was studied in chemical and manifest maturity-onset diabetics, in surgical patients and in alloxan diabetic rats. BK,mixed with insulin and injected subcutaneously twice daily in alloxan diabetic rats lowered the morning blood glucose concentration in a dose-dependent way, whereas in a control group treated with insulin only no decrease was seen. Accelerated local blood flow or enhanced vascular permeability as a cause of increased glucose uptake could be ruled out by control experiments using papaverine and eledoisin. Better metabolic control in the BK/insulin-treated group was also indicated by lower arterial levels of free fatty acids and of -hydroxybutyrate, normalized hepatic glycogen content and better growth of body weight. In healthy man an intravenous infusion of BK (80 g/h) did not influence normal fasting blood glucose concentrations, whereas elevated glucose levels in maturity-onset diabetics were continuously reduced within 100 min by 12.2±1.4%. A comparable diabetic group receiving saline alone showed no spontaneous drop of blood glucose concentration. An improvement of pathological carbohydrate metabolism by infusion of BK i.v. could also be demonstrated using the intravenous glucose tolerance test in chemical and manifest maturity-onset diabetics and in surgical patients: in all groupsk values of the glucose tolerance test were significantly increased by BK. This effect was neither due to stimulated insulin release nor to changed glucose pool or to increased renal glucose loss, which was even reduced by BK. Interestingly, normalk values in healthy volunteers were not further improved by BK. A stimulated protein breakdown, which occurs after surgery due to peripheral insulin resistance, can also be restricted by intravenous infusion of BK: in surgical patients urinary nitrogen excretion was reduced by 50% during infusion of BK and was accelerated again after cessation of the infusion. These results indicate that BK can improve the efficacy of exogenous insulin in insulin-deficient animals and depressed insulin sensitivity in maturity-onset diabetics and surgical patients. 相似文献
26.
Induction of rat acute-phase proteins by interleukin 6 in vivo 总被引:14,自引:0,他引:14
T Geiger T Andus J Klapproth T Hirano T Kishimoto P C Heinrich 《European journal of immunology》1988,18(5):717-721
Recombinant human interleukin 6 (rhIL 6) was injected i.p. into male Wistar rats to investigate its role as a mediator of the acute-phase response. Hepatic mRNA levels of beta-fibrinogen, alpha 2-macroglobulin, cysteine proteinase inhibitor, alpha 1-acid glycoprotein and albumin were measured at different times after the administration of rhIL 6. Maximal increases of mRNA concentrations were observed already 4 h after the injection of rhIL 6 leading to 4.8-, 19.7-, 10- and 16-fold stimulations in mRNA levels of beta-fibrinogen, alpha 2-macroglobulin, cysteine proteinase inhibitor or alpha 1-acid glycoprotein, respectively. The rhIL 6-induced stimulation of acute-phase protein mRNA was much more rapid than the acute-phase induction after turpentine, where maximal mRNA levels were found between 16 and 24 h. For all acute-phase proteins studied, the stimulation of mRNA synthesis was found to be dependent on the dose of rhIL 6 injected. In the case of alpha 2-macroglobulin mRNA a sex-specific induction by rhIL 6 was found. Only male rats showed an acute-phase response, whereas in female rats an acute-phase reaction of alpha 2-macroglobulin mRNA was not inducible by IL 6. The increases in mRNA levels of the acute-phase proteins studied were followed by corresponding changes of the proteins in the serum determined by rocket immunoelectrophoresis. It is concluded that IL 6 represents a potent mediator of the acute-phase response in the rat. 相似文献
27.
Clinical profiling of recombinant follicle stimulating hormone (rFSH; Puregon): relationship between serum FSH and efficacy 总被引:9,自引:0,他引:9
Single-dose and multiple-rising dose studies of recombinantfollicle stimulating hormone (rFSH) in hypogonadotrophic maleand female volunteers demonstrated that the rate of FSH absorptionafter i.m. injection is higher in men than in women. In theabsence of endogenous FSH, a correlation between serum FSH andbody weight became apparent. The elimination half-life of rFSHwas not different between the sexes and was comparable withurinary FSH. However, the in-vitro bio:immuno ratio of serumFSH was significantly higher after the administration of rFSHthan after urinary FSH. When rFSH was administered daily witha fixed dose, steady state levels were reached within 3-5 days.Serum FSH concentrations increased in a dose-dependent mannerwhen the daily dose was increased weekly over 3 weeks from 75to 225 IU. In hypogonadotrophic women, rFSH induced normal folliculargrowth whereas oestrogen synthesis was impaired. In women pituitarysuppressed by a high-dose oral contraceptive, the daily administrationof 150 IU rFSH for 1 week induced more and larger antral folliclesthan the same regimen with urinary FSH, whereas the serum immunoactiveFSH concentrations measured 24 h after each dosing were similar.It is concluded that even though equal or lower serum immunoactiveFSH concentrations were obtained following the administrationof rFSH compared with urinary FSH, circulating bioactivity FSHconcentrations were higher. Therefore, the conventional ideathat serum immunoreactive FSH correlates positively with themagnitude of the ovarian response should be reconsidered. 相似文献
28.
29.
Rivka Levy Bernard Czernobilsky Benjamin Geiger 《Virchows Archiv : an international journal of pathology》1991,418(5):447-455
Summary The aim of the present study was to explore the origin of cloacogenic carcinoma in the anal canal by immunohistochemical methods. We compared cytokeratin polypeptide expression of a cloacogenic carcinoma to normal anal epithelia, to anal squamous cell carcinoma and to basal and squamous cell carcinoma of the skin, using a battery of monoclonal anti-cytokeratin, polypeptide-specific antibodies. Our results indicate that cloacogenic carcinoma expresses cytokeratin polypeptides similar to those of the basal layer of anal squamous epithelium, of the anal transitional zone epithelium and of a layer of basal cells in the anal glands. Thus we concluded that each of the above cell types may be the cell of origin of cloacogenic carcinoma. 相似文献
30.
Dalia Khoury Alexander Preiss Paul Geiger Mohd Anwar Kevin Paul Conway 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundThe opioid crisis in the United States may be exacerbated by the COVID-19 pandemic. Increases in opioid use, emergency medical services (EMS) runs for opioid-related overdoses, and opioid overdose deaths have been reported. No study has examined changes in multiple naloxone administrations, an indicator of overdose severity, during the COVID-19 pandemic.ObjectiveThis study examines changes in the occurrence of naloxone administrations and multiple naloxone administrations during EMS runs for opioid-related overdoses during the COVID-19 pandemic in Guilford County, North Carolina (NC).MethodsUsing a period-over-period approach, we compared the occurrence of opioid-related EMS runs, naloxone administrations, and multiple naloxone administrations during the 29-week period before (September 1, 2019, to March 9, 2020) and after NC’s COVID-19 state of emergency declaration (ie, the COVID-19 period of March 10 to September 30, 2020). Furthermore, historical data were used to generate a quasi-control distribution of period-over-period changes to compare the occurrence of each outcome during the COVID-19 period to each 29-week period back to January 1, 2014.ResultsAll outcomes increased during the COVID-19 period. Compared to the previous 29 weeks, the COVID-19 period experienced increases in the weekly mean number of opioid-related EMS runs (25.6, SD 5.6 vs 18.6, SD 6.6; P<.001), naloxone administrations (22.3, SD 6.2 vs 14.1, SD 6.0; P<.001), and multiple naloxone administrations (5.0, SD 1.9 vs 2.7, SD 1.9; P<.001), corresponding to proportional increases of 37.4%, 57.8%, and 84.8%, respectively. Additionally, the increases during the COVID-19 period were greater than 91% of all historical 29-week periods analyzed.ConclusionsThe occurrence of EMS runs for opioid-related overdoses, naloxone administrations, and multiple naloxone administrations during EMS runs increased during the COVID-19 pandemic in Guilford County, NC. For a host of reasons that need to be explored, the COVID-19 pandemic appears to have exacerbated the opioid crisis. 相似文献