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1.
Two monoclonal antibodies capable of inducing granulosa cell apoptosis were produced against granulosa cells prepared from antral follicles of pig ovaries. The healthy follicles, 4-5 mm in diameter, were dissected from the ovaries of gilts, and then granulosa cells were isolated. BALB/c female mice were immunized with the isolated granulosa cells. Antibodies against the granulosa cells were detected by immunofluorescent staining using frozen ovarian sections. The isolated spleen cells prepared from immunized mice producing antibodies against the granulosa cells were fused with Sp2/O-Ag 14 mouse myeloma cells by standard hybridization techniques. Two hybridoma clones, PFG-1 and PFG-2, which produced specific IgM antibodies against granulosa cells were selected. Western blotting analysis revealed that PFG-1 and PFG-2 antibodies specifically recognized cell-membrane proteins with molecular weights of 55 and 70 kD and isoelectric points of 5.9 and 5.4, respectively. The monoclonal antibodies immunohistochemically reacted with granulosa cells of healthy follicles. When the isolated granulosa cells prepared from healthy follicles were cultured in medium containing 0.1 or 10 micrograms/m/PFG-1 or PFG-2 antibodies, respectively, the cells underwent apoptosis as determined by nuclear morphology, DNA electrophoresis and flow cytometric analysis. In conclusion, these two monoclonal antibodies against granulosa cells have cell-killing activity in cultured granulosa cells.  相似文献   

2.
Degenerative changes in membrana granulosa of ovaries in R. rattus have been studied using scanning electron microscopy. Ovaries from rats treated with atropine (300 mg/kg body weight) and testosterone propionate (10 IU) were used to study sequential course of atresia in granulosa cells. Granulosa cells undergoing atresia showed degenerative changes in following order i) loosening of intercellular matrix, ii) changed morphology and texture of secretory granules, iii) destabilization of granulosa cell membranes, iv) erosion of cell membrane, v) formation of specific degenerative belts, vi) pycnosis, vii) ghost cell formation and their subsequent mixing in hazzy follicular fluid of cyst. Phenomenon of atresia, its duration, course and underlying causes have been discussed.  相似文献   

3.
The cell cycle characteristics of mouse cumulus granulosa cells were determined before, during and following their expansion and mucification in vivo and in vitro. Cumulus-oocyte complexes (COC) were recovered from ovarian follicles or oviducts of prepubertal mice previously injected with pregnant mare serum gonadotrophin (PMSG) or a mixture of PMSG and human chorionic gonadotrophin (PMSG+hCG) to synchronize follicle differentiation and ovulation. Cell cycle parameters were determined by monitoring DNA content of cumulus cell nuclei, collected under rigorously controlled conditions, by flow cytometry. The proportion of cumulus cells in three cell cycle-related populations (G0/G1; S; G2/M) was calculated before and after exposure to various experimental conditions in vivo or in vitro. About 30% of cumulus cells recovered from undifferentiated (compact) COC isolated 43-45 h after PMSG injections were in S phase and 63% were in G0/G1 (2C DNA content). Less than 10% of the cells were in the G2/M population. Cell cycle profiles of cumulus cells recovered from mucified COC (oviducal) after PMSG+hCG-induced ovulation varied markedly from those collected before hCG injection and were characterized by the relative absence of S-phase cells and an increased proportion of cells in G0/G1. Cell cycle profiles of cumulus cells collected from mucified COC recovered from mouse ovarian follicles before ovulation (9-10 h after hCG) were also characterized by loss of S-phase cells and an increased G0/G1 population. Results suggest that changes in cell cycle parameters in vivo are primarily mediated in response to physiological changes that occur in the intrafollicular environment initiated by the ovulatory stimulus. A similar lack of S-phase cells was observed in mucified cumulus cells collected 24 h after exposure in vitro of compact COC to dibutyryl cyclic adenosine monophosphate (DBcAMP), follicle-stimulating hormone or epidermal growth factor (EGF). Additionally, the proportion of cumulus cells in G2/M was enhanced in COC exposed to DBcAMP, suggesting that cell division was inhibited under these conditions. Thus, both the G1-->S-phase and G2-->M-phase transitions in the cell cycle appear to be amenable to physiological regulation. Time course studies revealed dose-dependent changes in morphology occurred within 6 h of exposure in vitro of COC to EGF or DBcAMP. Results suggest that the disappearance of the S-phase population is a consequence of a decline in the number of cells beginning DNA synthesis and exit of cells from the S phase following completion of DNA synthesis. Furthermore, loss of proliferative activity in cumulus cells appears to be closely associated with COC expansion and mucification, whether induced under physiological conditions in vivo or in response to a range of hormonal stimuli in vitro. The observations indicate that several signal-transducing pathways mediate changes in cell cycle parameters during cumulus cell differentiation.  相似文献   

4.
BACKGROUND & AIMS: Restricted folate supply is associated with the development of carcinoma, and folate supplements have a protective effect in colorectal carcinoma. This effect may be mediated through correction of local folate deficiency. The aim of this study was to define the folate content of neoplastic colonic epithelial cells and its relation to that of adjacent normal tissue and circulating levels. METHODS: Epithelial cells were isolated from endoscopic biopsy specimens of normal, adenocarcinoma, adenoma, and adjacent normal colonic mucosa by ion chelation. Intracellular folate levels were determined by microbiological assay. RESULTS: Folate levels in carcinoma specimens were lower than in adjacent normal tissue (P < 0.02). Levels in adenoma epithelial cells were lower than in adjacent normal tissue, although this did not reach statistical significance (P < 0.06). Epithelial cells from normal tissue and mucosa adjacent to tumors and adenomata had similar folate contents. Blood folate and vitamin B12 indices for all groups were normal. CONCLUSIONS: Malignant colon epithelial cells show a relative localized folate deficiency. However, there is no evidence for the occurrence of generalized mucosal folate deficiency. This finding suggests that folate supplements do not inhibit carcinogenesis through correction of localized folate depletion.  相似文献   

5.
6.
The aim of this paper is to seek for the optimal cellular changes in the granulosa of ovarian follicles, leading to ovulation in minimal time. The granulosa cell population consists of proliferating, differentiated and apoptotic cells. Cell numbers are ruled by a system of differential equations, in which the control variables are the cell cycle exit and apoptosis rates. The conditions for ovulation are represented by three different constraints on the granulosa final state. We prove that the optimal strategy consists in applying permanently the minimal apoptosis rate and in switching the cell cycle exit rate from its minimal bound to its maximal one. We finally apply the optimal strategy on data providing the changes in the total cell number of ewe follicles during their terminal development.  相似文献   

7.
8.
Granulosa, interna and externa theca cells were isolated from large follicles of equine-chorionic-gonadotropin (eCG)-primed calves and co-cultured during 3 days in the absence or in the presence of dehydroepiandrosterone (DHEA). Co-cultures were performed by adding defined numbers of theca and/or granulosa cells which represented 0, 10, 20, 50 or 100% of total cells per well. Secretion of oestradiol-17beta (E2), androstenedione (A4) and progesterone (P4) depended on the type of theca cells (P < 0.001), on the percentage of seeded granulosa cells (P < 0.001) and on the day of culture (P < 0.001). DHEA increased (P < 0.001) E2 and A4, but not P4 (P > 0.05) productions. Interactions existed between these factors (P < 0.01). On day 1, A4 production was nil in granulosa cells alone. E2 production was negligible in theca cells alone but it increased when granulosa cells were added. E2 and A4 varied in an opposite manner according to the percentage of granulosa cells and with the type of theca cells. On day 3, without DHEA, E2 and A4 were low. On day 3 with DHEA, E2 production was maintained in granulosa cells alone but not with any combination of theca cells. In these conditions, A4 production was maintained in the presence of theca cells but not in granulosa cells alone. Granulosa cells alone secreted more P4 than theca cells. P4 increased as a function of the percentage of granulosa in co-cultures with externa but not interna theca cells with which it remained low. In conclusion, theca cells in culture have two effects in relation to the granulosa cells, which differ according to the steroid concerned and to the cell combination. Both types of theca cells have an inhibitory effect on E2 secretion whereas only interna theca cells are able to alter P4 production.  相似文献   

9.
A single injection of pregnant mare's serum gonadotropin (PMSG) into immature female rats was used to stimulate graafian follicle growth. The surface of granulosa cells in the growing follicles was examined at 12-hour intervals for 72 hours by scanning electron microscopy. Between 24 and 36 hours after injection of PMSG, microvillous processes appeared on the surface of the cells. These villous processes became fully developed at 48 hours and remained for at least 72 hours after PMSG injection. The significance of this PMSG-induced microvilli formation on granulosa cells is discussed.  相似文献   

10.
OBJECTIVE: To determine the concentration of the soluble form of intercellular adhesion molecule (ICAM)-1 in granulosa luteal cell-conditioned media and in follicular fluid (FF). DESIGN: Granulosa cells and FF samples were obtained at the time of oocyte retrieval for IVF. In 10 women, a total of 33 fluids were obtained from individual follicles, whereas in 70 women, the follicular aspirates were pooled. SETTING: Clinica "L. Mangiagalli" and Reproductive Center, San Raffaele Hospital, Milan, Italy. PATIENT(S): Eighty women referred for IVF for tubal factor or male factor infertility. INTERVENTION(S): Women underwent ovarian hyperstimulation. MAIN OUTCOME MEASURE(S): Soluble ICAM-1 was measured by an ELISA, and its levels were correlated with follicular size, the number of retrieved oocytes, and the number of follicles with a diameter of >15 mm. RESULT(S): The concentration of soluble ICAM-1 in granulosa luteal cell-conditioned media was 17.8 +/- 1.8 ng/5 x 10(5) cells. Interleukin-1beta can stimulate soluble ICAM-1 release in a dose-dependent manner. A significant positive correlation was demonstrated between levels of soluble ICAM-1 in pooled FF and the number of retrieved oocytes or the number of follicles with a diameter of >15 mm. CONCLUSION(S): Soluble ICAM-1 can be released by granulosa luteal cells and can be detected in FF after ovarian hyperstimulation. Levels of soluble ICAM-1 in FF correlate directly with some indices of ovarian function.  相似文献   

11.
Electron microscopy was used in a semi-quantitative study to determine changes in the abundance and size of surface nexuses and changes in the abundance of interiorized nexuses in growing and mature ovarian follicles during the ovulatory process. Mature follicles contain larger granulosa cells than follicles in the early stage of antral formation. Also, the granulosa cells of mature follicles have a slightly greater number of surface nexuses (without a change in nexus length), and more interiorized nexuses, compared to immature follicles. As a mature follicle approaches rupture, there is an appreciable decrease in the number of surface nexuses per granulosa cell. There is also a slight reduction in the number of interiorized nexuses at this time. It is concluded that this decrease in both surface nexuses and interiorized nexuses may be a consequence of ovulatory changes during which the rate of granulosa cell division is greater than the rate of formation of new nexuses. Additionally, the disruption to cell-to-cell cohesion during the ovulatory process appears to be independent of the interiorization of surface nexuses.  相似文献   

12.
Meishan gilts were ovariectomized 2 h after an i.v. injection of 5'-bromo-2'-deoxyuridine (BrdU, a thymidine analogue; 5 mg/kg body weight) on Days 15-19 of the estrous cycle or 24-30 h after observed estrus (post LH, PLH). All antral follicles > or = 3 mm from one ovary were fixed in Carnoy's solution. Granulosa and thecal cell labeling indexes (LI; percentage of nuclei staining for BrdU) as well as LI of cells within the basal, middle, and antral thirds of the granulosa cell layer were estimated for each follicle. In addition, antral and granulosa cell layer volume, granulosa cell layer thickness, granulosa cell density, number of granulosa cells, and number of S-phase cells per hour were estimated for each follicle. Mean follicular diameter increased linearly (p < 0.01) from Day 15 to PLH, with a growth rate of 0.77 mm/day. Granulosa and thecal cell LI decreased (p < 0.01) from Day 15 to PLH; however, granulosa cell LI was greater (p < 0.01) than thecal cell LI on Days 15 and 16 but less (p < 0.05) than thecal cell LI on Day 19. Follicles collected from PLH gilts contained no labeled granulosa cells. Cells within the basal third of the granulosa cell layer contained fewer (p < 0.01) labeled nuclei than did cells within the middle or antral thirds. In addition, LI within the basal and middle thirds of the granulosa cell layer decreased (p < 0.01) from Days 15 to 18 and from Days 15 to 17, respectively, whereas LI within the antral third remained constant from Days 15 to 18. Granulosa cell layer thickness was greatest (p < 0.01) on Day 15, then decreased (p < 0.01) and was similar from Day 16 to PLH. Granulosa cell density was similar from Days 15 to 19, then decreased (p < 0.01) for PLH gilts. Antral and granulosa cell layer volumes increased linearly (p < 0.01) from Days 15 to 19 and Day 15 to PLH, respectively, resulting in 2.8 and 1.9 volume doublings and doubling times of 1.4 and 2.7 days, respectively. Number of granulosa cells per follicle increased linearly (p < 0.01) from Day 15 to PLH, resulting in 1.5 cell doublings and a doubling time of 3.3 days. Number of S-phase cells per follicle per hour was similar from Days 15 to 18 and then decreased (p > 0.01) from Day 18 to PLH. In summary, the percentages of proliferating granulosa and thecal cells decreased throughout the final stages of antral follicular development. Differentiation of granulosa cells occurred from the basal to the antral area as follicles matured. We proposed that, during the latter stages of follicular development, the rapid increase in follicular diameter resulted primarily from expansion of the antral cavity, whereas increases in the granulosa cell layer volume and number of granulosa cells per follicle maintained a constant granulosa cell layer thickness.  相似文献   

13.
This paper describes, from a mathematical viewpoint, the cellular changes in the granulosa of ovarian follicles during their terminal development. A dynamic model takes into account the processes of (1) cell division, (2) exit from the cell cycle towards differentiation, and (3) apoptotic cell death. Proliferative cells leave the cycle in an irreversible way. The risk of entering apoptosis applies to non-cycling cells. Changes in the cell numbers and in the growth fraction are derived from differential equations. The transitions between the different cell states are ruled by time-dependent rates. Numerical applications of the model concern ovulating and degenerating ovarian follicles in the ewe. The main feature of the ovulating case is the progressive exhaustion of the proliferating compartment for the benefit of the non-cycling cells. From an initial mainly proliferative state the granulosa progressively switches to a highly differentiated state, so that the growth fraction continuously decreases. In the atretic cases, the pattern of changes in the total viable cell number is influenced by the follicular age at the onset of the apoptotic process and by the intensity of the cell death rate. As apoptosis affects the non-cycling cells, the growth fraction is no longer strictly decreasing. The sensitivity of the model to the parameters is studied in a more general framework than the granulosa cell population.  相似文献   

14.
A biofeedback gait training system for step length is proposed, adapted to the correction of spatial walking asymmetries by means of a simple, quick and reliable method for daily clinical use. The system is composed of a walkway and a gait analysis device (locometer) measuring the main temporal and distance factors of gait. The step length is imposed on the subject by lighted targets appearing on the walkway, alternately on the right and left side; the subject is asked to place a swinging foot on the lighted target. Feedback to the subject is supplied by direct visual information (the subject looking at the movement and the position of the foot with respect to the lighted target) and an acoustic signal delivered in real time when the length step error is greater than an allowed value. The method is validated on a population of hemiparetic patients who have suffered from a stroke and who have been reeducated with traditional rehabilitation methods. The patients were divided into two groups; one group following a gait training with biofeedback (BFB group) and one group following a gait training without biofeedback (reference group). Preliminary results are presented, showing a significant beneficial effect of the biofeedback method in increasing the step length of paretic limbs and in correcting step-length asymmetry.  相似文献   

15.
Mouse oocytes secrete a factor(s) that inhibits progesterone and enhances estradiol production by cumulus granulosa cells. The purpose of this study was to investigate the mechanisms by which the production of these steroids is modulated. Mouse oocyte-cumulus cell complexes (intact) and complexes from which the oocytes were removed microsurgically (oocytectomized; OOX) were cultured for up to 48 h in the presence of FSH (150 ng/ml) and testosterone (5 x 10(-7) M). For these experiments, all cells were obtained from antral follicles of 24- to 26-day-old mice primed with eCG. Intact complexes produced primarily estradiol, with significant accumulation occurring between 24 and 48 h. In contrast, OOX complexes produced little estradiol but, starting at 18 h of culture, released significantly more progesterone than did intact complexes. Progesterone accumulation in cocultures of denuded oocytes with either OOX complexes or monolayers of mural granulosa cells was significantly reduced compared to that with OOX complexes or mural granulosa cells cultured alone. If dibutyryl cAMP replaced FSH in the cocultures, similar results were obtained, suggesting that the oocyte-secreted steroid-regulating factor acts downstream of the generation of cAMP to inhibit progesterone production. Since estradiol can inhibit progesterone production by granulosa cells, we investigated the possibility that the increased progesterone released by OOX complexes was secondary to the lower estradiol production. Intact complexes cultured in the presence of the nonaromatizable androgen, 5 alpha-dihydrotestosterone, or steroidal (4-hydroxyandrostenedione) or non-steroidal (CGS 16949A) aromatase inhibitors produced little estradiol; however, progesterone production by these complexes was no different from that of estradiol-producing intact complexes. These results suggest that the steroid-regulating factor(s) secreted by occytes acts to regulate granulosa cell production of estradiol and progesterone by independent mechanisms.  相似文献   

16.
To investigate the involvement of extracellular matrix (ECM) in folliculogenesis in the sheep, parallel changes in ECM components and key steroidogenic enzymes were studied by quantitative immunohistochemistry and immunoblotting during follicular growth and atresia. Growth of ovarian follicles from 1 to 5 mm in diameter was characterized by a progressive increase in P450 cholesterol sidechain cleavage levels in both thecal (p < 0.001) and granulosa cells (p < 0.001), an increase in P450 aromatase levels in granulosa cells of follicles larger than 3.5 mm (p < 0.001), and an increase in levels of P450 17 alpha-hydroxylase C17,20 lyase (P450(17 alpha)) in the theca interna. In addition, during follicular growth, a change in localization of cells expressing P450(17 alpha) within the theca interna was observed, positive cells being sparse within the theca interna of small follicles and specifically located close to the basal laminae in large follicles. In parallel, follicular growth was associated with an increase in levels of type I collagen in granulosa cell layers (p < 0.01) and an increase in levels of fibronectin (p < 0.05), particularly the specific ED-A alternatively spliced variant of fibronectin, in the theca externa. Follicular atresia was characterized by a loss of P450 aromatase in granulosa cells (p < 0.001) and a decrease in levels of P450(17 alpha) in the theca interna (p < 0.05). Simultaneously, levels of fibronectin (p < 0.05), particularly the ED-A variant of fibronectin, decreased in the theca externa of atretic follicles. Within the wall of granulosa cells, levels of fibronectin (p < 0.05), laminin, type IV collagen, and heparan sulfate proteoglycans strongly increased during follicular atresia. Overall, these results show that follicular growth and atresia were associated with distinct changes in levels of ECM components, suggesting that ECM components may play a role in the regulation of proliferation, differentiation, and apoptosis of follicular cells.  相似文献   

17.
The beta-galactosidase reporter gene, either free or complexed with various cationic vectors, was microinjected into mammalian cells. Cationic lipids but not polyethylenimine or polylysine prevent transgene expression when complexes are injected in the nucleus. Polyethylenimine and to a lesser extent polylysine, but not cationic lipids, enhance transgene expression when complexes are injected into the cytoplasm. This latter effect was independent of the polymer vector/cDNA ionic charge ratio, suggesting that nucleic acid compaction rather than surface charge was critical for efficient nuclear trafficking. Cell division was not required for nuclear entry. Finally, comparative transfection and microinjection experiments with various cell lines confirm that barriers to gene transfer vary with cell type. We conclude that polymers but not cationic lipids promote gene delivery from the cytoplasm to the nucleus and that transgene expression in the nucleus is prevented by complexation with cationic lipids but not with cationic polymers.  相似文献   

18.
Early nursing reforms in the 19th century are usually associated with Nightingale, although later emphasis has been placed on similar movements in the Poor Law sector. Extension of nursing influence over decision-making in terms of nursing practice and education is charted, using examples from 19th century Minutes of hospital committees and more recent experience based mainly on the observations made by one of the writers, who had substantial input into steering the hospital through the stages prior to achieving National Health Service (NHS) Trust status. The significance of nurse executive power following the 1990s NHS reforms is highlighted and means of extending the use of this authority are explored.  相似文献   

19.
A reversed-phase high performance liquid chromatographic (HPLC) assay developed for the CP-93,393-1 drug substance was adapted for use with CP-93,393-1 tablets. Using a novel experimental matrix, validation was performed to obtain linearity, reproducibility and recovery and to meet current regulatory requirements. Deviations in the sample preparation procedure were performed to demonstrate the ruggedness of the assay.  相似文献   

20.
OBJECTIVE: To test the effect of cisapride on symptom score and on fasting and postprandial antral area in patients with dysmotility-like functional dyspepsia compared with controls. METHODS: Nineteen consecutive patients with dysmotility-like functional dyspepsia (13 females, six males, aged 18-79 y) and 12 control subjects (six females, six males, aged 19-68 y) were investigated. A symptom score including six upper digestive symptoms rated from 0 to 3 was applied. The patients received in a randomized order cisapride 10 mg t.i.d. (n = 10), or placebo (n = 9) for 3 days. The controls also received cisapride (n = 6) or placebo (n = 6) in the same way. The antral area in fasting condition and immediately after a semiliquid test meal (250 ml, 342 kcal) was assessed by real-time ultrasonography in front of the aorta and mesenteric vein. The measurements were carried out before starting and after finishing the trials with cisapride and placebo. RESULTS: The symptom score (mean +/- SD) was 7.1 +/- 2.4 in dysmotility-like functional dyspepsia vs 0.5 +/- 0.2 in controls (P < 0.0001). The fasting antral area was 4.5 +/- 0.9 cm2 in dysmotility-like functional dyspepsia vs 2.2 +/- 0.2 cm2 in controls (P < 0.0001). Postprandial antral area was also larger in dysmotility-like dyspepsia than in controls (6.2 +/- 1.0 vs 3.0 +/- 0.3 cm2, Pb= 0.0001). Symptom score correlated with fasting antral area in dysmotility-like functional dyspepsia (rb= 0.38, Pb= 0.05). Cisapride decreased the symptom score to 4.5 +/- 2.5 (P = 0.0009) and placebo to 5.3 +/- 2.4 (P = 0.02). Cisapride significantly reduced the fasting antral area and the postprandial antral area in the dyspeptic group, but not in the control group. Postprandial antral expansion was not influenced by cisapride. Placebo did not change the sonographic parameters in both groups. CONCLUSIONS: In dysmotility-like functional dyspepsia, fasting and postprandial antral areas are wider than in controls. Despite a good placebo response, cisapride is effective in improving the symptoms in dysmotility-like functional dyspepsia, associated with the reduction of fasting and postprandial antral areas.  相似文献   

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