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1.
The specific activity of enkephalinase in endometrial tissue of nonpregnant ovulatory women is correlated in a highly significant, positive manner with the plasma level of progesterone. The specific activity and levels of enkephalinase messenger ribonucleic acid and immunoreactive protein also are increased in human endometrial stromal cells in culture by treatment with a synthetic progestin, medroxyprogesterone acetate (MPA), in a time- and dose-dependent manner. From an analysis of the temporal relationship between the specific activity and half-life of enkephalinase in endometrial tissue and the level of progesterone in plasma, it appeared highly likely that some mechanism, in addition to progesterone withdrawal, was operative to reduce enkephalinase activity in endometrium during the late luteal phase of the ovarian cycle before progesterone levels had declined below those known to be effective for progesterone action. In stromal cells previously (and concurrently) treated with MPA (10(-9) mol/L), the addition of transforming growth factor-beta 1 (TGF beta 1) or TGF beta 2 (1 ng/mL) to the medium caused a decrease in enkephalinase specific activity despite the continued presence of MPA. The half-life of enkephalinase (activity) in stromal cells treated with MPA plus TGF beta 1 was 2.8 days, which is similar to the computed half-life for enkephalinase in endometrial tissue during the mid- to late secretory phase of the endometrial cycle (2.5 days). Simultaneous treatment of endometrial stromal cells with MPA (10(-9) mol/L) and TGF beta 1 (1 ng/ mL) prevented the progestin-induced increase in enkephalinase specific activity and immunoreactive enkephalinase protein. Thus, TGF beta acts to oppose the progesterone-induced increase in enkephalinase expression in endometrial stromal cells, even in the continued presence of MPA.  相似文献   

2.
This study examined steroid-regulated expression of the metalloproteinase stromelysin-1 in primary human endometrial stromal and decidual cells. Immunoblot analysis using a specific polyclonal antibody against stromelysin-1 revealed that the progestin medroxyprogesterone acetate (MPA) produced a time-dependent reduction in a band at 50,000 mol wt. Although the cells were refractory to estradiol (E2) alone, E2 plus MPA further reduced the intensity of this stromelysin-1 zone. By 6 days of incubation, MPA inhibited levels of secreted stromelysin-1 by one third, and E2 plus MPA inhibited stromelysin-1 levels by two thirds compared with the control values. This differential responsiveness of the stromal cells to the two steroids is reported for several biochemical end points of decidualization. Northern analysis indicated pronounced inhibition of stromelysin-1 messenger ribonucleic acid (mRNA) by E2 plus MPA over a concentration range that simulated circulating progesterone levels of the luteal phase (10(-8) mol/L) through pregnancy (10(-6) mol/L). After suppression of stromelysin-1 expression in the stromal cell monolayers by E2 plus MPA, steroid withdrawal led to a several-fold enhancement of stromelysin-1 mRNA by 4 days and of the stromelysin-1 protein by 7 days. Given its actions in degrading several extracellular matrix components and activating other MMP zymogens, steroid withdrawal-enhanced stromelysin-1 activity could mediate a proteolytic cascade that promotes the rapid tissue destruction and vascular disruption associated with menstruation. Stromelysin-1 expression by cultured decidual cells isolated from first trimester endometrium was also reduced by MPA and synergistically reduced by E2 plus MPA. As activation of the 92-kilodalton gelatinase/type IV collagenase, a crucial mediator of trophoblast invasiveness, is stromelysin-1 dependent, reduced decidual stromelysin-1 production could help to limit trophoblast invasion.  相似文献   

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The objectives of this investigation were to examine in vivo insulin like-growth factor-I (IGF-I) secretion by the human midcorpora lutea (mid-CL) and the effects of IGF-I, hCG, FSH, and human GH on progesterone (P) production by CL cells obtained from patients at laparotomy. We first examined whether the CL produces IGF-I by measuring IGF-I levels in the ovarian vein from the ovary bearing the CL. The IGF-I concentration in the ovarian vein bearing the CL (206 +/- 31 ng/mL) was significantly increased compared to the concentration in the contralateral ovarian vein (179.2 +/- 32 ng/mL; P < 0.05). Luteal cells isolated from mid-CL were cultured in serum-free medium 199 in the presence and absence of hCG, FSH, GH, and graded concentrations of IGF-I. At the end of the incubation period (24 h), P levels in the medium were measured by RIA. The treatment with IGF-I (0.1-10 ng/mL) showed a dose-dependent stimulatory action of IGF-I on P synthesis in the luteal cell system, being maximal between 5-10 ng/mL. The treatment with hCG (10 IU/mL), IGF-I (5 ng/mL), and GH (1000 ng/mL) increased basal P synthesis by 300%, 80%, and 30%, respectively (P < 0.001 and P < 0.05). FSH (100 ng/mL), either alone or in combination with IGF-I, failed to stimulate P synthesis. Treatment with IGF-I monoclonal antibody (1:5000) completely reduced P synthesis induced by 5 ng/mL IGF-I and slightly reduced basal P synthesis as well as GH-stimulated P synthesis by human midluteal cells. To further evaluate the specific role of IGF-I on luteal steroidogenesis, IGF-I receptor was identified by chemical cross-linking of [125I]IGF-I to mid-CL membranes. Experiments conducted in the absence and presence of unlabeled IGF-I (500 ng) revealed proteins with characteristics of the type I IGF receptor. These results are consistent with multihormonal regulation of P synthesis by the human mid-CL. hCG and IGF-I play a major role in the stimulation of P synthesis and, to a lesser extent, human GH. These in vivo and in vitro data suggest that the CL is a site of secretion, action, and reception of IGF-I during the midluteal phase.  相似文献   

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Differentiation of endometrial stromal cells (decidualization) is essential for embryo implantation and maintenance of pregnancy. By sequential complementary DNA subtractive hybridization, one of the messenger RNAs (mRNA) induced by progesterone in human endometrial stromal cells decidualized in vitro was identified as that of a tissue transglutaminase type II (TGase). TGase mRNA was induced within 6 h after the addition of progesterone to the culture, and the effect was dose dependent. Both the TGase inhibitor monodansylcadaverine and oligodeoxynucleotide complementary to the TGase mRNA inhibited the decidualization, as assessed by PRL production and morphological transformation. Expression of TGase mRNA in human decidua and endometria exposed to high levels of progesterone in vivo was demonstrated by Northern blotting and in situ hybridization. These data suggest that TGase is necessary for the decidualization of human endometrial stromal cells and that clarification of the mechanism of action of TGase will facilitate further insight into the diagnosis and treatment of infertility.  相似文献   

7.
During in vitro decidualization of human endometrial stromal cells (HESCs), medroxyprogesterone acetate (MPA) inhibits expression of the potent extracellular matrix (ECM)-degrading protease stromelysin-1 (MMP-3), but enhances PRL expression. Consistent with its priming role in vivo, estradiol (E2) augments these effects. In the current study, immunoblot analysis revealed that coincubation with 10(-6) M RU 486 blocked the inhibition in HESC-secreted MMP-3 levels (50,000 mol wt) evoked by 10(-8) M E2 + 10(-7) M MPA. Although MPA can act as a glucocorticoid, the HESCs were refractory to 10(-7) M dexamethasone added alone or with E2. Because E2 elevates progesterone but not glucocorticoid receptor levels, MPA and RU 486 control MMP-3 expression as a progestin and antiprogestin, respectively. To study RU 486 involvement in steroid withdrawal leading to menstruation, HESCs were decidualized during 10 days incubation with E2 + MPA, and parallel cultures were kept in E2 + MPA or withdrawn to either control or RU 486-containing medium. Compared with E2 + MPA-suppressed HESCs, increases in levels of secreted MMP-3 (2.0-fold), and its 2.1-kilobase messenger RNA (10-fold) were observed in HESCs after 4 days of withdrawal to control medium, with much greater increases seen in RU 486-containing medium (10-fold protein, 100-fold messenger RNA). Previously, we showed that RU 486 up-regulated E2 + MPA-inhibited plasminogen activator expression in the cultured HESCs. Extrapolation of these in vitro observations to endometrial events following RU 486 administration suggests that coordinate enhancement of MMP-3 and plasminogen activator expression promotes proteolysis of the stromal/decidual ECM, which leads to endometrial sloughing. Moreover, destabilization of endometrial microvessels resulting from degradation of their surrounding ECM is consistent with the heavy menstrual bleeding stemming from RU 486 administration. However, in contrast to the marked RU 486-initiated reversal of MMP-3 expression, RU 486 did not significantly reverse E2 + MPA-enhanced PRL secretion by the cultured HESCs. Interestingly, decidual PRL, unlike decidual MMP-3, does not appear to play a role in menstruation. Interleukin-1 beta counteracted E2 + MPA-mediated inhibition of secreted MMP-3 levels, implying that leukocyte/trophoblast-derived cytokines can modulate steroid-regulated MMP-3 expression by stromal/decidual cells during menstruation and pregnancy.  相似文献   

8.
Prostaglandin E2 (PGE2) is an endogenous hormone of adrenal zona glomerulosa cells and is released in response to stimulation by agonists such as angiotensin II (Ang II). It stimulates the release of aldosterone from cultured bovine adrenal zona glomerulosa cells. These studies were designed to determine whether this steroidogenic effect of PGE2 was mediated by an EP1, EP2, or EP3 receptor. Prostaglandin E2 and 11-deoxy PGE1, an EP2-selective agonist, stimulated aldosterone release in a concentration-related manner with an ED50 of 300 nmol/L for PGE2 and 2 micromol/L for 11-deoxy PGE1. The maximal effect of PGE2 was less than that of angiotensin II. 17-Phenyl trinor PGE2, an EP1-selective agonist, required concentrations of 100 micromol/L to stimulate aldosterone release and sulprostone, an EP3/EP1-selective agonist, failed to alter aldosterone release. The EP1-selective antagonist SC19220 failed to alter basal or PGE2-stimulated aldosterone release over a range of concentrations. PGE2 and 11-deoxy PGE1 also stimulated an increase in both intracellular and extracellular cAMP. This increase was time- and concentration-related. The ED50 for PGE2 was 9.8 micromol/L. 17-Phenyl trinor PGE2 and sulprostone were without effect. Using fura-2 loaded cells, PGE2 (2 micromol/L), dibutyryl cAMP (2 mmol/L), and Ang 11 (2 micromol/L) increased intracellular calcium over basal concentrations by 5.5-fold, 3-fold, and 6.2-fold, respectively. Like PGE2, dibutyryl cAMP also stimulated aldosterone release. PGE2- and dibutyryl cAMP-induced aldosterone release were blocked by the calcium channel inhibitor diltiazem. These studies indicate that PGE2 is a potent stimulus for aldosterone release and that the effect is mediated by EP2 receptors. Both cAMP and calcium appear to mediate the steroidogenic effect of PGE2 and calcium seems to be distal to cAMP.  相似文献   

9.
OBJECTIVE: To describe the phenotype in a family with dominantly inherited cone-rod dystrophy with chromosome assignment to a 19q locus, and to correlate this with current classifications of this retinal dystrophy. DESIGN: A detailed clinical examination including Goldmann perimetry was undertaken in all family members. Six members under the age of 30 years underwent dark-adapted electroretinography, color contrast-sensitivity measurement, dark-adapted static perimetry, and dark adaptometry. PATIENTS: The study included 34 affected and 22 unaffected patients in four generations of a pedigree that manifested autosomal dominant cone-rod retinal dystrophy linked to a chromosome 19q locus by genetic linkage analysis. RESULTS: Loss of visual acuity occurred in the first decade of life, onset of night blindness occurred after 20 years of age, and little visual function remained after the age of 50 years. Central and, later, peripheral retinal fundus changes were associated with central scotoma, pseudoaltitudinal field defects, and finally global loss of function. Psychophysical and electrophysiologic testing before the age of 26 years showed more marked loss of cone than rod function. CONCLUSIONS: The phenotype associated with this mutation does not fit well into previous subtypes of cone-rod dystrophy. Further studies will be needed to correlate specific genetic mutations in this group of conditions with the various clinical phenotypes.  相似文献   

10.
A case of peripheral ameloblastoma in a 57-years-old woman is presented, along with a discussion of the clinical and histological characteristics of the lesion. After clinical and radiographic examinations, and with a differential diagnosis of pyogenic granuloma, an excisional biopsy was performed and the material collected was sent for histological examination. On the basis of the histopathological diagnosis, a second operation was performed with a wide safety margin, including bone tissue, which did not show any involvement with the odontogenic neoplasm.  相似文献   

11.
Tamoxifen given for breast cancer therapy, has a complex and an unclear action on the endometrium. A large number of literatures has attributed the proliferous changes in the endometrium caused by tamoxifen (Tam). No report has appeared on the endometrial cellular changes induced by Tam. The present study shows a significant (P < 0.001) increase in the proliferative activity due to Tam in endometrial stromal cells over control and estradiol (E2). This in vitro model is useful for the study of the hyperplasic effect of Tam at the cellular level.  相似文献   

12.
The study of immortalization and other alterations associated with neoplastic transformation of endometrial stromal cells is important to understanding the development of uterine sarcomas and mixed tumors. Because stromal cells are important regulators of associated epithelial cells, alterations in the regulation of stromal cell proliferation that influence epithelial cells may also contribute to the development of endometrial carcinomas. To study immortalization and associated phenotypic and genetic alterations of human endometrial stromal cells, cultures were transfected with a plasmid containing an ori-, temperature-sensitive mutant SV40, A209 (tsSV40). Morphologically transformed colonies were selected and propagated at the permissive temperature until they entered 'crisis'. In contrast to human fibroblasts, every clone tested was immortalization competent. The frequency of immortalization was approximately 1 x 10(-6). One uncloned and six cloned cell lines escaped from crisis and appear to be immortal. Two clones, M4 and B10T1, were selected for further study. Immortalization is conditional; proliferative arrest occurs at the restrictive temperature for large T antigen function. Furthermore, withdrawal of the large T antigen results in expression of the senescent phenotype of enlarged, flattened cells. Colony-forming efficiency at the restrictive temperature was undetectable. Immortalization is also associated with several genetic alterations. The DNA content of tsSV40 transfected cells was either diploid or tetraploid in the precrisis stage of proliferation, but became aneuploid upon immortalization. Several structural rearrangements of chromosomes were detected in the immortalized stromal cells which differ from those found in SV40 immortalized fibroblasts. Although their capacity for anchorage-independent proliferation (AIP) is variable, tsSV40-immortalized endometrial stromal cells have a higher capacity for AIP than their tsSV40-transfected progenitor cells in the period of proliferation prior to 'crisis'.  相似文献   

13.
A case of crossed aphasia is presented in a strongly right-handed 77-year-old white female without history of familial sinistrality or prior neurological illness. She developed a right middle cerebral artery infarction documented by CT and accompanied by obvious clinical signs of a conduction aphasia with some resolution but continuing obvious language defect after 9 weeks in rehabilitation. Comprehensive neuropsychological and aphasia testing suggested anomalous lateralization of phonologic-output aspects of language, emotional prosody, motor planning and body schema modules with usual lateralization of lexical-semantic aspects of language and visuo-spatial functions. Experimental validation of the uncrossed lexical-semantic aspects of language using tachistoscope methods found support for the Alexander-Annett theory that different aspects of language can be dissociated in their lateralization. The subject had difficulty identifying a semantic associate of a picture presented to the left visual field (7 errors out of 10) relative to right visual field presentation (2 errors out of 10). Bilateral free naming errors (6 and 5 errors in the left and right visual fields, respectively) occurred consistent with the aphasic presentation, suggesting phonologic-output dysfunction from the right cerebral vascular accident. Implications of the results for aphasia classification are discussed.  相似文献   

14.
IL-10 is a well-documented immunosuppressant that inhibits macrophage-dependent Ag presentation and CD4+ T cell proliferation in vitro. We report that IL-10 inhibits alloantigen-specific proliferative responses and induces a long lasting anergic state in human purified CD8+ T cells when added concomitantly with the Ag in the presence of APC. Moreover, the generation of allospecific cytotoxic activity is inhibited by IL-10. These effects are indirect and are mediated through inhibition of the costimulatory functions of APC. In contrast, IL-10 has no direct inhibitory effects on the proliferation of purified CD8+ T cells activated by anti-CD3 mAb and promotes the growth of activated CD8+ T cells in combination with low doses of IL-2. Taken together, these results indicate that IL-10 has differential effects on CD8+ T cells depending on their state of activation, which may explain both the enhancing and inhibitory effects observed after IL-10 treatment in different in vivo experimental models.  相似文献   

15.
The information available concerning the effects of chemotherapy administered during pregnancy is limited and consists of case reports and small series. A registry has been established at the National Cancer Institute, but there are currently only several hundred cases of neonates exposed to chemotherapy registered. All clinicians who care for women receiving chemotherapy during pregnancy should report those experiences to the National Cancer Institute to increase the data base. When chemotherapy is used during the embryogenesis period in the first trimester there is an increased rate of spontaneous abortion and major birth defects. The most toxic chemotherapeutic agents administered during pregnancy are methotrexate and aminopterin and should be avoided when possible, particularly during the first trimester. Pregnancy-related physiologic changes should be kept in mind when dosing and administering cytotoxic chemotherapy. The risk of fetal malformation when chemotherapy is administered during the second and third trimesters is probably not greater than background rate, but there may be a greater risk of stillbirth, fetal growth restriction, premature birth, and maternal and fetal myelosuppression. Breastfeeding should be avoided in women receiving chemotherapy.  相似文献   

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In 20 rats bronchitis was evoked by permanent 12-week long inhalation of SO2. For this purpose a special chamber with gas supply was prepared. In all rats exposed to SO2 changes in cellularity of BALF were found (a statistically significant increase of the percent of macrophages and neutrophils). Histologic examination revealed bronchial changes especially in epithelium. The method applied, based on an original technology is cheap and effective and can be recommended in developing experimental bronchitis.  相似文献   

18.
OBJECTIVE: To determine whether premature progesterone elevation affects the timing of hyperechogenic transformation of the endometrium during the early luteal phase of controlled ovarian hyperstimulation (COH) cycles. DESIGN: Prospective analysis. SETTING: Assisted Reproduction Unit, H?pital Antoine Béclère, Clamart, France. PATIENT(S): Fifty-nine women undergoing 59 IVF-ET cycles. INTERVENTION(S): Patients underwent COH with a GnRH agonist and hMG. Endometrial echogenicity was assessed on the days of hCG administration, oocyte retrieval, and ET. Results are expressed as the extent of submyometrial hyperechogenic area in relation to the total endometrial surface as determined by a computer-assisted analysis system. Patients were sorted according to whether their plasma progesterone level exceeded 0.9 ng/mL (n = 26) or not (n = 33) on the day of hCG administration. MAIN OUTCOME MEASURE(S): Endometrial echogenicity. RESULT(S): On the day of hCG administration, the degree of endometrial echogenicity was similar in both groups (41% vs. 40%), but after hCG administration, it increased significantly faster in the high progesterone group than in the low progesterone group (70% vs. 63% at oocyte retrieval and 90% vs. 79% at ET, respectively). CONCLUSION(S): End-follicular phase elevation in plasma progesterone (>0.9 ng/mL on the day of hCG administration) was associated with a faster increase in endometrial echogenicity during the early luteal phase of COH cycles. This observation is consistent with the hypothesis that premature progesterone elevation hastens the secretory transformation of the endometrium.  相似文献   

19.
OBJECTIVE: We investigated whether patient-centered communication skills can be taught to residents in Internal Medicine by using a time-limited behaviorally oriented intervention. METHOD: Residents working at the Department of Internal Medicine were randomly assigned to an intervention group (IG; N = 19) or a control group (CG; N = 23). In addition to 6 hours of standard medical education per week, the IG received specific communication training of 22.5 hours duration within a 6-month period. Initially and 10 months later, participants performed interviews with simulated patients. Interviews were rated by blinded raters who used the Maastricht History and Advice Checklist-Revised. RESULTS: Compared with the CG, the IG improved substantially in many specific communication skills. Both groups improved in the "amount of medical information identified" and in the ability to "communicate about feasibility of treatment." CONCLUSION: Patient-centered communication skills such as those presented in this intervention study can be taught. The ability to gain medical information and the readiness to communicate about aspects of medical treatment seem to improve with more professional experience; however, they also profit from the intervention.  相似文献   

20.
We recently reported that picomolar doses of norethindrone (NET), a synthetic analog of 19-nortestosterone, significantly stimulated human TE85 osteosarcoma cell proliferation, differentiation, and activity in vitro. In the present study, we investigated the possibility that NET interacts with another osteogenic agent, i.e., fluoride, to stimulate human TE85 osteosarcoma cell proliferation, differentiation, and activities. Bone cell proliferation was measured by the stimulation in [3H]thymidine incorporation. Differentiation was monitored by the increase in alkaline phosphatase-specific activity. Osteoblastic activity was assessed by the stimulations in collagen synthesis and in osteocalcin secretion (in the presence of 1 nM 1,25-dihydroxyvitamin D3). When the human TE85 cells were incubated with mitogenic doses of NET and fluoride concurrently, the stimulatory effects of the two agents on these parameters exhibited no significant interaction. The enhancing effect of NET on the osteogenic effect of fluoride was not due to a shift of the fluoride dose response curve. Pretreatment with NET for 24 h followed by a treatment with a mitogenic dose (i.e., 100 microM) of fluoride for an additional 24 h significantly and synergistically potentiated the effects of fluoride on the [3H]thymidine incorporation, alkaline phosphatase-specific activity, collagen synthesis, and osteocalcin secretion, compared with those with the subsequent vehicle (0.05% ethanol) treatments. In contrast, pretreatment with fluoride for 24 h before the addition of NET for 24 h did not produce significant synergistic stimulations in the test parameters. Pretreatment of TE85 cells with the same doses of dihydrotestosterone or progesterone prior to treatment with fluoride under the same conditions did not induce synergistic potentiation of fluoride in [3H]thymidine incorporation, suggesting that the synergistic interaction with fluoride is probably not a common property of anabolic sex steroids. In summary, we found that: (1) the osteogenic effects of fluoride and NET were additive when cells were treated with both agents concurrently; (2) a 24-h pretreatment with picomolar doses of NET potentiated the osteogenic actions of fluoride in human TE85 osteosarcoma cells; and (3) pretreatment with NET produced a subsequent fluoride response that was synergistic. In conclusion, these findings led us to speculate that the osteogenic actions of NET and fluoride act through different mechanisms, and that NET at low doses has a permissive effect on the osteogenic effects of fluoride, and as such NET may be used in concert with fluoride to increase osteoblast proliferation, differentiation, and activity.  相似文献   

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