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71.
Evidence for cell-specific changes with age in expression of oestrogen receptor (ER) alpha and beta in bone fractures from men and women 总被引:7,自引:0,他引:7
Batra GS Hainey L Freemont AJ Andrew G Saunders PT Hoyland JA Braidman IP 《The Journal of pathology》2003,200(1):65-73
Oestrogen is recognized as important for maintaining bone mass in men and women. Oestrogen receptor (ER) alpha and the recently described ER-beta are both expressed in bone cells, but have different affinities for oestrogen agonists and plant oestrogens, which could be important in developing treatments for bone loss in both men and women. It is unclear, however, which isoform predominates in bone; cell type and age may influence their relative expression. The present study has compared ER-alpha and ER-beta expression in serial sections of human fracture callus from males (n = 19, age range 5-72 years) and females (n = 15, age range 3-86 years) by indirect immunoperoxidase. Fracture callus was used as it can be readily obtained from individuals over a wide age range and contains a variety of bone cells. Antibody specificity was confirmed by western blotting and comparison of immunoreactivity in sections of breast tumour and benign prostate hyperplasia. No gender difference in ER expression was found in bone from individuals less than 40 years old. Proliferative chondrocytes were positive for both isoforms, but few larger hypertrophic cells were immunoreactive. ER-alpha and ER-beta were co-expressed in osteoclasts, suggesting that oestrogen may act directly on these cells. Osteoblasts, osteocytes, and mesenchymal cells also expressed both isoforms. In women over 40 years of age, however, relatively fewer biopsies contained osteocytes positive for ER-alpha and ER-beta. Likewise, the proportions of osteoblasts and mesenchymal cells expressing ER-beta were reduced but ER-alpha remained unaffected. In contrast, in men over 40 years, only the proportion of biopsies containing ER-beta-positive mesenchymal cells was lower. In these older men and women, ER-alpha and ER-beta expression was retained by the small proliferative chondrocytes. These results demonstrate that gender, age, and cell type are important determinants of ER isoform expression in skeletal cells. 相似文献
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Chung C.C.; Fleming R.; Jamieson M.E.; Yates R.W.S.; Coutts J.R.T. 《Human reproduction (Oxford, England)》1995,10(12):3139-3141
The aim of this prospective randomized controlled study wasto determine the possible role of ovulation induction with intrauterineinsemination (IUI) in the treatment of unexplained infertility.A total of 100 patients were randomized to receive ovulationinduction with or without IUI. All patients were treated withlong-course gonadotrophinreleasing hormone analogue (GnRHa),starting in the luteal phase, and exogenous follicle stimulatinghormone (FSH) to induce follicular growth. Ovulation was inducedusing human chorionic gonadotrophin and timed intercourse (TI)was advised 2448 h later or IUI was effected 3648h later. Both the cycle fecundities (21.8 and 8.5%) and thecumulative ongoing pregnancy rates after three cycles (42 and20%) were significantly higher (P < 0.03) in the IUI groupthan in the TI group respectively. This is a clear indicationthat ovulation induction with IUI is an effective treatmentmethod for unexplained infertility, but ovulation inductionwith TI has a negligible impact in this large group of patients. 相似文献
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Four groups of female golden hamsters were exposed to short photoperiods (SP, LD 10:14) for 4, 14, 20, or 27 weeks and tested for physiological markers (uterine weight and estrous cycles) and behavioral (lordosis, approach and aggressive behaviors) measures while in contact with a stud male. After behavioral testing, females were ovariectomized and, during the next 2 weeks, were tested twice more (with a stud male) after replacement with 0.33 microgram (low dose) and 1.0 microgram (high dose) EB plus progesterone (500 micrograms). Results show that, after 14 weeks of SP conditions, uterine weights and percentage of females showing normal estrous cycles are at a minimum. This is mirrored by minimal levels of lordosis and maximal levels of aggressive and approach behavior at week 14. Physiological measures did not fully recover (to preregression levels) until week 27; however, behavioral measures show an earlier recovery by week 20. SP exposure also affects the circadian patterning of behaviors: Females that show lordosis at week 14 did so later in the day than did females tested at other weeks. Females in the regressed state also fail to show a significant decrease in approach behaviors (and a significant increase in receptive behaviors) over the course of the circadian day, a pattern seen in nonregressed females. Following hormone replacement with the low EB (+P) dose, females do not become receptive; however, at the higher dose, all but the week 14 group show increased receptivity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
77.
R. G. Schaub C. J. Dunn M. R. Deibel A. E. Berger D. Wunderlich W. E. Fleming 《Inflammation research》1990,31(1-2):127-134
Human leukocyte suspensions (neutrophils 80–85%, monocyte 15–20%) were incubated alone or with cultured human umbilical vein endothelial cells. Leukocytes were either directly added to the endothelial cell cultures or separated from them by a 0.4 micron insert filter. Supernatants or cell lysates were obtained at 0.5, 1, 2, and 4 hours of incubation. Supernatants were assayed for the prostacyclin (PGI2) metabolite 6-keto prostaglandin F1 and prostaglandin E2 (PGE2) by radioimmunoassay and for interleukin-1 (IL-1) by the thymocyte co-mitogen assay. Cell lysates were analyzed for cell-associated procoagulant activity (PCA). Co-incubation of endothelial cells with leukocytes stimulated the synthesis of PGI2, PGE2, and PCA. These biochemical changes correlated partially with the release of IL-1 beta. The results suggest that IL-1 released in monocyte/neutrophil co-cultures can produce prothrombotic (increased PCA expression) and inflammatory changes (increased synthesis of vasodilatory and permeability enhancing PGI2 and PGE2) in endothelial cells. Neutrophils may represent a source of the released IL-1 and/or may act to stimulate monocyte release of this cytokine and thus play an important role in vascular pathology by a mechanism unrelated to their more direct cytotoxic activity. 相似文献
78.
We describe a polycystic lesion of the kidney in the CBA/N mouse with an X-linked recessive immunodeficient syndrome. There is progressive cystic dilatation affecting all parts of the nephron. The cyst lining is composed of a single layered epithelium with focal nuclear crowding and the formation of micropapillary structures. The cystic epithelial cells show subnuclear vacuolation. Focal basement membrane thickening is also a feature. There is no significant inflammatory infiltrate present within these kidneys. Electron microscopic examination reveals that the subnuclear vacuolation is due to loss of the membrane infoldings at the basal pole of the epithelial cell with fluid accumulation within the extracellular space. The basement membrane thickening is due to expansion of the lamina densa. These changes are not present at birth but develop progressively with age. The finding of a polycystic kidney lesion in these mice offers an opportunity to investigate the relationship between the immune system and renal cyst formation. 相似文献
79.
Christine R. Critchley Jennifer Fleming Dianne Nicol Paula Marlton Megan Ellis Lisa Devereux Gordana Bruce Ian Kerridge 《European journal of human genetics : EJHG》2021,29(3):503
Various forms of private investment are considered necessary for the sustainability of biobanks, yet pose significant challenges to public trust. To manage this tension, it is vital to identify the concerns of relevant stakeholders to ensure effective and acceptable policy and practice. This research examines the aspects of commercialisation that are of most concern to the Australian public (n = 800) and patients who had donated their tissue to two large disease specific (cancer) public biobanks (n = 564). Overall, we found a commercialisation effect (higher support for public relative to private) in relation to funding, research location and access to stored biospecimens. The effect was strongest for research locations and access compared to funding. A latent class analysis revealed the pattern of concern differed, with the majority (34.1%) opposing all aspects of commercialisation, a minority supporting all (15.7%), one quarter (26.8%) opposing some (sharing and selling tissue) but not others (research locations and funding), and a group who were unsure about most aspects but opposed selling tissue (23.5%). Patient donors were found to be more accepting of and unsure about most aspects of commercialisation. Members of the (general) public who were motivated to participate in biobanking were more likely to oppose some aspects while supporting others, while those who indicated they would not donate to a biobank were more likely to oppose all aspects of commercialisation. The results suggest that approaches to policy, engagement and awareness raising need to be tailored for different publics and patient groups to increase participation.Subject terms: Genetics research, Ethics 相似文献
80.
Three studies were conducted to determine the effects of reproductive condition and hormonal background on the acquisition and retention of a prior maternal experience. In the first study five experience conditions were compared. All animals gave birth and received either no postpartum contact with pups or 1/2 hr, 1 hr, 2 hr or 24 hr of pup contact and were tested for maternal behavior 10 days later. Animals receiving pregnancy and parturitional experience, but minimal social experience with young, exhibited significantly longer maternal onset latencies than did groups receiving 2 or 24 hr of prior experience; also, comparisons of 10- and 30-day retention intervals indicated that animals tested 10 days after a 24-hr experience exhibited shorter latencies than those tested 30 days later. Thus, the duration of the postpartum experience and the interval since prior experience both affect the level of maternal responsiveness shown. In the second study six groups of females were tested. Four groups were permitted one day of interaction with pups either after parturition (primiparous animals) or following pup induction procedures (nulliparous animals) and were tested for their maternal responsiveness to foster pups 25-35 days later, either on day 19 of a subsequent pregnancy or following resumption of estrous cycling. For most measures of maternal behavior there were significant main experience and test effects; experienced and pregnant animals exhibited shorter latencies to retrieve, lick and crouch over pups than did inexperienced and cycling animals, respectively. Significant interactions were also found for genital licking latency as well as for retrieval and crouch frequencies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献