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1.
The purpose of this study was to determine and compare the follicular phase steroid hormone secretion into the utero-ovarian vein by the ovary with a dominant follicle and the contralateral ovary in the same baboon. Serial utero-ovarian vein blood from both sides was collected in 25 baboons by the use of a laparoscope on alternate days, starting on day 1 or 3 of the cycle and continuing through 2 to 3 days post-ovulation. Approximately 3–4 days before the day of expected ovulation, samples were collected at 8-hr intervals. Steroids estradiol (E2) and progesterone (P) were measured in all utero-ovarian vein plasma by radioimmunoassay. In the peripheral plasma, E2, P, LH, and FSH measurements were carried out. Concentrations of steroids were significantly higher on the side of the ovulating ovary by day 5 before ovulation. Individual plots however, indicated that some baboons may establish the dominant side as early as day 11 before ovulation. The preovulatory gonadotropins had a differential effect on the two ovaries. For example, E2 values on the ovulatory side ovary declined after increases in LH/FSH, whereas on the contralateral side these values had increased. Both sides showed increases in the level of P with the increases in LH. The mean interval from E2 peak to LH peak was 24 hrs and LH peak to ovulation was 24 hrs.  相似文献   
2.
Copulatory behavior unrelated to conception is sometimes observed in some non-human primates including the Japanese monkey. In the present study, the authors examined whether a mature follicle or a newly formed fresh corpus luteum was observed in the ovaries of female Japanese monkeys which displayed the copulatory behavior unrelated to conception. Post-conception copulatory behaviors were observed in three out of four females usually kept in individual cages in an air-conditioned room, and in two out of three females without infants kept in an outdoor group cage. However, neither a mature Graafian follicle nor a fresh corpus luteum formed newly after conception was observed in any of these females by laparoscopic examinations conducted immediately after termination of the copulatory behavior. In females with infants born in the preceding birth season, copulatory behaviors were observed in three out of four females kept in the outdoor group cage, and in two out of four females in a free-ranging troop. Ovulation was confirmed in one case out of the three kept in the outdoor group cage, but neither a mature follicle nor a newly formed corpus luteum was observed in the remaining four females. These findings suggest that copulatory behavior in the Japanese monkey is not always controlled by the development of a follicle or ovulation in the ovary.  相似文献   
3.
Human follicular fluid (hFF), which has been treated with either unspecific proteases or dextran-coated charcoal (DCC) to remove proteins and/or steroids, cannot successfully induce the acrosome reaction (AR). After the removal of steroids, AR-inducing activity can be restored to hFF by supplementation with exogenous progesterone, but only in the presence of intact protein. Gel filtration experiments with 3H-progesterone-labelled hFF showed elution of the radioactive signal in the high molecular weight range, corresponding to bound progesterone. AR-inducing activity was seen in exactly the same fraction. Based on these results, the acrosome reaction-inducing substance (ARIS) appears to be a complex of progesterone and a progesterone-binding protein, which was shown to be identical with the plasma protein corticosteroid-binding globulin (CBG) by immunological techniques. AR induction was only observed in the presence of both CBG and progesterone, suggesting a combined effect of the two components. © 1995 wiley-Liss, Inc.  相似文献   
4.
目的探讨滤泡树突细胞肉瘤(FDCS)的临床表现、病理形态、免疫组化、生物学行为和预后,提高对该病的认识。方法对2例滤泡树突细胞肉瘤进行报道,并结合临床资料、肿瘤大体及镜下特征、免疫组化标记结果及预后和国内外文献进行分析。结果2例FDCS,1例发生于颈部淋巴结,另1例发生于肠系膜,镜检肿瘤由梭形及卵圆形细胞组成,呈束状、漩涡状、编织状排列;免疫组化显示肿瘤细胞CD21、CD23和CD35阳性;患者预后不良。结论滤泡树突细胞肉瘤是一种罕见且容易误诊的低度恶性肿瘤,组织化学和免疫组化染色有助于该肿瘤的诊断及鉴别诊断,减少误诊。  相似文献   
5.
《Reproductive biology》2022,22(2):100633
The role of adipokines in ovarian-related disorders such as polycystic ovary syndrome (PCOS) has been reported. However, the involvement of Oncostatin M (OSM), a recently identified adipokine, in ovarian function is unknown. Therefore, we investigated the association of the OSM signaling pathway with ovarian functions and PCOS pathogenesis. This case-control study enrolled 30 PCOS and 30 healthy women who underwent the intracytoplasmic sperm injection procedure. OSM and OSM receptor (OSMR) levels were evaluated in the follicular fluid (FF). Moreover, the expression of insulin receptor substrates (IRS1 and IRS2), OSM, OSMR, suppressor of cytokine signaling 3 (SOCS3), and androgen receptor (AR) genes were analyzed in the isolated cumulus cells (CCs). For the in-vitro experiment, the effect of recombinant OSM on the expression of related genes in isolated CCs was analyzed. Follicular concentrations of OSM and OSMR were significantly lower in PCOS (123.91±48.58 pg/ml and 0.93±0.35 ng/ml, respectively) compared to control women (283.53 ± 96.62 pg/ml and 1.45 ± 0.18 ng/ml, respectively; p < 0.001) and were positively correlated with the oocyte maturation (r = 0.611 and r = 0.611, respectively) and fertilization (r = 0.592 and r = 0.627, respectively) rates in the PCOS group. Furthermore, the SOCS3 expression was upregulated about eight times in PCOS patients compared to the controls (p < 0.05). The treatment of cells with recombinant OSM significantly increased SOCS3, OSMR, IRS-1, and -2 expression and decreased AR expression. The decreased levels of OSM and its receptor in PCOS patients, possibly mediated by SOCS3, could negatively affect oocyte maturation and fertilization rates.  相似文献   
6.
Attraction of spermatozoa by way of chemotaxis to substances secreted from the egg or its surrounding cells has been demonstrated in marine species, amphibians, and mammals. This process is species- or family-specific in marine invertebrates: a chemoattractant for one marine species is usually not recognized by another species or by a member of another family. It is not known whether this selectivity is also the rule in other phyla. Furthermore, it is not at all obvious that such selectivity would be advantageous to species with internal fertilization. Here, using a directionality-based assay for chemotaxis, we studied in vitro the chemotactic response of human and rabbit spermatozoa to human, rabbit, and bovine egg-related factors. We found that spermatozoa from each of the two sources responded similarly well to egg-related factors obtained from any of the three species examined. These results indicate lack of chemotaxis-related, species specificity between these species, suggesting that their sperm chemoattractants are common or very similar. The findings further suggest that mammals do not rely on species specificity of sperm chemotaxis for avoidance of interspecies fertilization.  相似文献   
7.
In HIV-infected patients, large quantities of HIV are associated with follicular dendritic cells (FDCs) in lymphoid tissue. During antiretroviral therapy, most of this virus disappears after six months of treatment, suggesting that FDC-associated virus has little influence on the eventual outcome of long-term therapy. However, a recent theoretical study using a stochastic model for the interaction of HIV with FDCs indicated that some virus may be retained on FDCs for years, where it can potentially reignite infection if treatment is interrupted. In that study, an approximate expression was used to estimate the time an individual virion remains on FDCs during therapy. Here, we determine the conditions under which this approximation is valid, and we develop expressions for the time a virion spends in any bound state and for the effect of rebinding on retention. We find that rebinding, which is influenced by diffusion, may play a major role in retention of HIV on FDCs. We also consider the possibility that HIV is retained on B cells during therapy, which like FDCs also interact with HIV. We find that virus associated with B cells is unlikely to persist during therapy.  相似文献   
8.
The objective was to investigate the effects of oxygen tension and follicle cells (FCs) during in vitro maturation of porcine oocytes in only porcine (Sus scrofa domesticus) follicular fluid (pFF), using static and non-static (rotating) culture systems, on the nuclear maturation and subsequent in vitro fertilization of the oocytes. In the first experiment, cumulus-oocyte complexes (COCs) were matured for 48 h in pFF supplemented with (+) or without (−) FCs (5.2 × 106 cells/mL), using the static (S) and rotating (R) culture systems (+FC/S, −FC/S, +FC/R, and −FC/R) under 5% or 20% O2. Co-culture with FCs in the static culture system (+FC/S) had a detrimental effect on the meiotic competence of oocytes, whereas co-culture with FCs in the rotating culture system (+FC/R) increased maturation rates. In both culture systems, oxygen tension had no apparent effects on meiotic competence of oocytes, irrespective of culture system and FC addition. In the second experiment, COCs were matured under 5% or 20% O2 using the −FC/S or +FC/R culture systems and then fertilized. Oxygen tension had no significant effects on fertilization parameters, irrespective of the culture system. The rotating culture system increased rates of sperm penetration and male pronuclear formation and decreased polyspermic fertilization compared with the static culture system (P < 0.05). In conclusion, both −FC/S and +FC/R culture systems supported meiotic competence, irrespective of oxygen tension. However, the +FC/R culture system may be superior to the −FC/S culture system for promoting fertilization.  相似文献   
9.
Cell morphology and proliferation was investigated in the atretic follicles during estrous cycles in the guinea pig. Ovarian samples on days 1, 4, 8, 12 and 16 of the estrous cycle in the guinea pig were taken in the morning for histologic staining with hematoxylin and eosin (HE), and immunohistochemical staining of the protein proliferating cell nuclear antigen (PCNA). The results indicated that the granulosa cells degenerated and eliminated first in atretic follicles, while the fibroblast-like cells appeared in the innermost layer of theca interna cells. When the fibroblast-like cells migrated to the antrum, they proliferated and formed a new tissue in peripheral to the zona pellucida of the oocyte. Our results also revealed that the orientation of the theca interna cell arrangement changed twice during the process of atresia, and the loose connective tissue in the antrum was critical for follicular atresia. Therefore, follicular atresia was not a simple process of cell death and elimination, but coexisted with cell proliferation. To our knowledge, we have for the first time confirmed cell proliferation and the presence of new tissue in atretic follicles in guinea pigs.  相似文献   
10.
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