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1.
2.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
3.
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
4.
Inconsistent expression of both centromeres of a dicentric Y chromosome in a child with ambiguous external genitalia. 总被引:1,自引:1,他引:1 下载免费PDF全文
A newborn child with ambiguous external genitalia had evidence of internal female development on the left and internal male development on the right. Blood chromosome analysis showed three cell types: 45,X; 46,XY with the Y being submetacentric and about twice the usual size with two 'centromeric' C bands; and 46,X,dic(Y). Chromosome studies from the skin, uterus, and Fallopian tube showed almost exclusively 45,X cells. This represents the second reported patient in whom two centromeres are inconsistently expressed though present as shown by two 'centromeric' C bands. 相似文献
5.
P. K. Rønnevik J. E. Nordrehaug G. von der Lippe 《European journal of clinical pharmacology》1995,48(2):127-131
The effects of the 1-selective -adrenergic blocker metoprolol on physiological responses, exercise capacity and gas exchange parameters were measured in healthy men using different graded bicycle exercise protocols on separate days before and following administration of 200 mg controlled-release metoprolol. Eleven men performed in randomised order maximal cardiopulmonary exercise testing on 50-W/6-min stage, 50-W/3-min stage and ramp (15-W/min–1) protocols. Peak heart rate and peak heart rate-blood pressure products were similar on all exercise protocols, and were significantly reduced by metoprolol. Submaximal and peak oxygen consumption were similar before and following -adrenoceptor blockade. Depending on the exercise protocol applied, an insignificant decrease of 4–10% in maximal cumulated exercise capacity (work-rate × time integral) was observed following administration of metoprolol. It is concluded that in healthy men evaluated with different exercise protocols the 1-selective controlled-release -adrenoceptor blocker metoprolol does not influence exercise capacity despite a marked reduction of heart rate and rate-pressure product. 相似文献
6.
7.
N. Butkow Dr. A. M. Wheatley I. Th. Lippe R. H. Marcus C. Rosendorff 《Basic research in cardiology》1990,85(3):297-306
Summary The hyperthyroid rat myocardium exhibits enhanced contractility. There is evidence that altered calcium handling by the myocardium may be responsible for this enhanced state. To investigate this, isolated hyperthyroid and cuthyroid hearts were perfused in the working mode and exposed to alterations in external calcium concentration. Heart rate was not significantly different in either group of hearts, nor was it altered by the change in calcium. The concentration of calcium needed to elicit half-maximal contractility (dP/dtmax) was lower in the hyperthyroid (0.81±0.07 mM) than in the cuthyroid hearts (1.12±0.09 mM, p<0.05). This increase in calcium sensitivity was unlikely to be at the site of the sarcolemma as verapamil exerted equal negative inotropic effects on both groups of hearts. Dantrolene, which blocks calcium release from the sarcoplasmic reticulum, exerted a significantly greater (p<0.01) depression in dP/dtmax after 12 min in the hyperthyroid (50±7%) than in the cuthyroid heart (15±2%). We conclude from our results that the enhanced contractile state of the hyperthyroid rat heart is likely to involve an altered mechanical response to calcium which is possibly at the level of enhanced calcium release from the sarcoplasmic reticulum. 相似文献
8.
Paul Emery Janet E. Pope Klaus Kruger Ralph Lippe Ryan DeMasi Sadiq Lula Blerina Kola 《Advances in therapy》2018,35(10):1535-1563
Despite recommendations suggesting that biological and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) should be used in combination with methotrexate in the treatment of rheumatoid arthritis (RA), up to one-third of patients with RA are treated with monotherapy. The objective of the systematic literature review reported here was to evaluate the clinical evidence regarding the efficacy of b/tsDMARDs as monotherapy in the treatment of RA. MEDLINE®, Embase®, and the Cochrane Central Trials Register (to April 11, 2017) and the American College of Rheumatology and European League Against Rheumatism conference proceedings (2010–2016) were searched for randomized controlled trials evaluating the efficacy of b/tsDMARDs as monotherapy for RA in adults. Forty-four monotherapy studies of abatacept, adalimumab, baricitinib, certolizumab pegol, etanercept, sarilumab, sirukumab, tocilizumab, and tofacitinib reported in 71 publications were identified. Tocilizumab had the most studies (14), followed by etanercept (10) and adalimumab (9). These b/tsDMARDs were consistently shown to be efficacious treatments, regardless of whether patients were intolerant of or had never used conventional synthetic (cs) DMARDs. However, better treatment outcomes were usually achieved with combination therapy, and this was observed for all b/tsDMARDs assessed by this review. Only a few studies provided a head-to-head comparison between b/tsDMARD treatments or between b/tsDMARD monotherapy and combination therapy, and as many were initial RA treatments they were not generalizable to usual care. In conclusion, evidence from randomized trials suggests that the b/tsDMARDs studied are effective as monotherapy. In general, some patient responses seem better with combination therapy and the durability of monotherapy is less than combination therapy. There is, however, a need for longer-term head-to-head trials to establish positioning of these interventions in the treatment algorithm for RA.Funding: Pfizer.Plain Language Summary: Plain language summary available on the journal website. 相似文献
9.
Growth hormone mediates the growth of T-lymphoblast cell lines via locally generated insulin-like growth factor-I 总被引:3,自引:0,他引:3
M E Geffner N Bersch B M Lippe R G Rosenfeld R L Hintz D W Golde 《The Journal of clinical endocrinology and metabolism》1990,71(2):464-469
It has become evident that locally produced insulin-like growth factors-I and -II (IGF-I and IGF-II) play an important role in the medication of GH action upon tissues. To explore this concept with respect to immunocompetent cells, we analyzed IGF production and clonogenic responsiveness of immortalized human T-cell lines established from seven normal controls and four Laron dwarfs. While the normal T-cell lines showed significant augmentation of basal colony formation in response to both IGF-I and GH, little increase in clonogenesis in response to GH was seen with the Laron T-cell lines. Assay of basal and GH-stimulated conditioned media demonstrated low, but measurable, levels of IGF-I and IGF-II from both normal and Laron T-cells. Under serum-free incubation conditions, GH stimulation of normal T-cell lines failed to generate significant increases in mean IGF-I or IGF-II concentration and no increase in the mean IGF-II concentration in conditioned medium were observed after GH stimulation of Laron T-cell lines. Nevertheless, the increased cloning efficiency of the normal T-cell lines in response to either GH or IGF-I was nearly completely abrogated by preincubation of cells with antibodies to either IGF-I or the type I IGF receptor. These studies, thus, support a role for locally generated IGF-I in the mediation of GH action on T-lymphocytes and indicate that this effect is mediated via the type I IGF receptor. 相似文献
10.
Effect of sensory denervation with capsaicin on liver fibrosis induced by common bile duct ligation in rat 总被引:2,自引:0,他引:2
Alessandro Casini Irmgard Th. Lippe Stefano Evangelista Pierangelo Geppetti Paolo Santicioli Carmelo Urso Milena Paglierani Carlo Alberto Maggi Calogero Surrenti 《Journal of hepatology》1990,11(3):302-312
Hepatic fibrosis represents an important stage in the progression of chronic liver disease to cirrhosis. In the present paper we have investigated whether capsaicin-sensitive neuropeptide-containing sensory neurons may participate in the development of liver fibrosis. The expression of hepatic fibrosis induced by common bile duct obstruction has been studied both in capsaicin- and vehicle-treated rats. Common bile duct-induced liver fibrosis was less marked in capsaicin-treated rats than in vehicle-treated rats. Diffuse alterations of liver parenchyma structure with marked collagen deposition and nodular regeneration occurred 8 weeks after common bile duct ligation in vehicle-treated animals, while none of the capsaicin-treated rats exhibited the formation of complete connective septa altering the parenchyma architecture. Both vehicle- and capsaicin-treated rats showed an increasing number of desmin-positive cells in the perivenular zone, but the density of these cells was lower in treated animals than in untreated rats. The hydroxyproline content of the liver increased after common bile duct ligation in a time-dependent manner. Eight weeks after bile duct obstruction vehicle-treated rats showed a 7-fold increase of liver collagen content in comparison to normal animals. This enhancement was about 3.5-fold in capsaicin-treated rats. These findings raise the possibility that the peripheral release of neuropeptides stored in sensory nerves might participate in the development of liver fibrosis following common bile duct obstruction. 相似文献