Removal of hydrosalpinges increases endometrial leukaemia inhibitory factor (LIF) expression at the time of the implantation window

BACKGROUND: The presence of hydrosalpinges is associated with lower implantation and pregnancy rates in women undergoing IVF-embryo transfer, while salpingectomy improves these parameters. Although the mechanism by which hydrosalpinges affects fertility is not entirely understood, an adverse effect on endometrial receptivity has been postulated. In this study, we hypothesized that the adverse effects of hydrosalpinges on fertility may be in part mediated by inappropriate endometrial expression of leukaemia inhibitory factor (LIF), a cytokine implicated in implantation. METHODS: In order to test our hypothesis, we prospectively examined the expression of LIF during the window of implantation in the endometrium of infertile women (n = 10) with hydrosalpinges prior to and following salpingectomy and of fertile controls (n = 10) by Western blotting and immunohistochemistry. RESULTS: LIF expression was significantly lower in infertile women with hydrosalpinges compared with fertile controls (P < 0.05). Salpingectomy resulted in an increase in LIF expression in eight out of 10 women with hydrosalpinges. LIF levels were increased by 231 +/-49% (mean +/- SEM) following salpingectomy. Immunohistochemical analysis confirmed the Western blot findings. The increased LIF immunoreactivity was predominantly localized to luminal and glandular epithelial cells. CONCLUSIONS: Our findings suggest that observed benefit from salpingectomy in infertile women with hydrosalpinges may be in part mediated by the up-regulation of endometrial LIF expression.     

白内障晶状体上皮细胞及晶状体纤维超微结构的观察

应用胎儿晶状体发育的超微结构为形态学依据,观察老年性、外伤性、先天性白内障晶状体的超微结构.结果:老年性白内障晶状体上皮多数细胞膜破裂,作者首先发现其原因是相邻细胞顶部的紧密连结缺失,房水侵入所致.胞质中线粒体空泡化,内质网扩张、脱粒.晶状体纤维膨胀、崩溃.细胞之间的各种连结消失.外伤性白内障除具有白内障特点外,胞质中出现大量溶酶体、残体.1例先天性白内障,上皮细胞发育尚好,晶体纤维不发育.     

Self-Regulated Facial Muscle Tension Effects on Intraocular Pressure

This study was designed to examine the relationship between orbicularis muscle tension around the eyes and fluctuations in intraocular pressure (IOP) in normal subjects. Using a biofeedback paradigm, 20 male and female subjects were asked to increase and decrease their EMG activity from the orbicularis muscle while receiving EMG feedback. Subjects received 3 alternating blocks of trials in which they attempted to increase and decrease muscle tension while maintaining the eyes open. A fourth trial consisted of a forceful closure of the eyes during the increase period. IOP was measured every 60 s throughout the entire sequence, and electrodes placed above and below the eye recorded eyeblinks. Results suggest that IOP increases with increases in facial muscle tension in normal subjects, a finding which cannot be accounted for by changes in eyeblink frequency. These results imply that increases in IOP occur during periods of increased muscle tension around the eye and suggest that muscle tension levels should be examined among individuals who have abnormally high IOP levels.     

Diagnosis of retinoblastoma by fine-needle aspiration and aqueous cytology

This article reports the cytodiagnosis of three cases of retinoblastoma in children aged 1.5, 2.5, and 5 yr. Two of them were diagnosed by fine-needle aspiration cytology of the primary tumor and one by aqueous cytology. The tumor cells were usually round to oval, small and uniform, with scanty cytoplasm; they generally occurred in closely packed clusters of variable sizes. We discuss the differential diagnosis of retinoblastoma with other round-cell tumors of childhood involving the orbit.     

Mouse blastocysts release a lipid which activates anandamide hydrolase in intact uterus

Anandamide (N-arachidonoylethanolamine, AEA) is a major endocannabinoid, known to impair mouse pregnancy and embryo development and to induce apoptosis in blastocysts. Here we show that mouse blastocysts rapidly (within 30 min of culture) release a soluble compound, that increases by approximately 2.5-fold the activity of AEA hydrolase (fatty acid amide hydrolase, FAAH) present in the mouse uterus, without affecting FAAH gene expression at the translational level. This "FAAH activator" was produced by both trophoblast and inner cell mass cells, and its initial biochemical characterization showed that it was fully neutralized by adding lipase to the blastocyst-conditioned medium (BCM), and was potentiated by adding trypsin to BCM. Other proteases, phospholipases A(2), C or D, DNAse I or RNAse A were ineffective. BCM did not affect the AEA-synthesizing phospholipase D, the AEA-binding cannabinoid receptors, or the selective AEA membrane transporter in mouse uterus. The FAAH activator was absent in uterine fluid from pregnant mice and could not be identified with any factor known to be released by blastocysts. In fact, platelet-activating factor inhibited non-competitively FAAH in mouse uterus extracts, but not in intact uterine horns, whereas leukotriene B(4) or prostaglandins E(2) and F(2)alpha had no effect. Overall, it can be suggested that blastocysts may protect themselves against the noxious effects of uterine endocannabinoids by locally releasing a lipid able to cross the cell membranes and to activate FAAH. The precise molecular identity of this activator, the first ever reported for FAAH, remains to be elucidated.     

Implantation, interception and contraception

The factors involved in post-fertilization events leading toimplantation in mammals are discussed with special referenceto potential forms of interception. The stages of embryonicgrowth until implantation are considered initially. The growthand differentiation of the uterine endometrium is then described,followed by the events occurring during the apposition and invasionof the implanting embryo. Several potential approaches to newforms of interception are considered, and the advantages anddisadvantages of each of them are evaluated. Among them, newvaccines against the zona pellucida, inactivation of the secretionsof the blastocyst, hatching, the activity of the pinopodes,and the endometrial proteins produced in the secretory phaseseem to offer various and varied targets. Some existing methodsof fertility regulation may act by affecting these stages ofdevelopment, e.g. RU486 may interfere with pinopod function.Various physiological and embryonic consequences of interferingwith these stages of pregnancy are discussed.     

Differentiation of endometrial stromal cells in vitro: down-regulation of suppression of the cell cycle inhibitor p57 by HOXA10?

Decidualization is a critical step during embryo implantation that is characterized by the differentiation of endometrial stromal cells (ESC) into decidua cells. However, the mechanism of differentiation remains largely unknown. Previously, it has been shown that the null function of homeo box A10 (HOXA10) causes defects in both implantation and decidualization, suggesting that the HOXA10 signalling pathway is likely to be involved in uterine decidualization. In the present study, we determined the expression and subcellular distribution of HOXA10 and its downstream molecule, p57, in ESC during in vitro decidualization induced by a combination of 8-bromo-cAMP and medroxyprogesterone acetate. We demonstrated that the HOXA10 was down-regulated while in contrast, p57 was up-regulated in the process of decidualization. Immunocytochemistry and transient expression of the HOXA10 tagged with green fluorescence protein revealed that there were no differences in the HOXA10 subcellular localization between the induced and non-induced ESC. Our results suggest that the down-regulation of HOXA10 may contribute to increased p57 and that up-regulation of p57 likely plays an important role in ESC differentiation in the process of decidualization. The progesterone receptor pathway may participate in promoting ESC to exit the cell cycle and enter differentiation.     

人工晶体植入前后视觉诱发电位的临床分析

目的:(1)探讨白内障囊外摘除术前术后及人工晶体植入术后视觉诱发电位幅值及潜时变化特征;(2)探讨白内障囊外摘除术术前P—VEP,F—VEP,F—ERG联合预测的必要性。方法:采用重庆泰克医电仪器公司产TEC—100C视觉电生理仪。对白内障患者实行分组测量。术前均测F—ERG,P—VEP,部分病例增测F—VEP。结果:114例术前F—ERG正常,P—VEP测量其P_(100)波幅值潜时均异常:P_(100)波幅值降低,潜时延长,术后及人工晶体植入后幅值,潜时都有所改善,而并发性白内障,代谢性白内障变化不明显。结论:据视觉诱发电位的变化,老年性白内障组,外伤性白内障组术后应及时装入人工晶体,并发性白内障组,代谢性白内障组装入人工晶体临床意义不大。术前联合测试(VEP ERG)对视力预后、以及眼底病变的定量诊断意义重大。     

Secretory role for human uterodomes (pinopods): secretion of LIF

The differentiation of human endometrial epithelium is a dynamic event, which occurs throughout the menstrual cycle in preparation for pregnancy. The appearance of uterodomes (pinopods) in this regard was first introduced in rodents with an established pinocytotic function, whereas little evidence was available in humans in this context. This study was undertaken to identify the potential physiological roles of uterodomes in the implantation process. To address this, endometrial biopsies from early, mid- and late luteal phases of the menstrual cycle of 23 fertile female patients with regular menses were used. Scanning and transmission electron microscopies (SEM and TEM) as well as immunofluorescence and immunogold TEM were performed to study the morphological changes and the expression pattern of leukaemia inhibitory factor (LIF) at uterodomes. Our results illustrated a high level of LIF expression in the human uterodomes, which was colocalized with the well-known biochemical markers of exocytosis, including syntaxin-1, 25-kDa synaptosomal protein (SNAP-25) and vesicle-associated membrane protein-2 (VAMP-2). Our morphological and immunocytochemical findings illustrated a secretory function for human uterodomes for the first time. In conclusion, this novel function for uterodomes provides an important clue in detection of their physiological function(s) during the process of the plasma membrane transformation.     

Uterine contractility decreases at the time of blastocyst transfers

High-frequency uterine contractions at the time of non-cavitating embryo transfer influence adversely IVF-embryo transfer outcome. This prompted us to quantify prospectively the possible decline in uterine contraction frequency occurring during later stages of the luteal phase of ovarian stimulation, up to the time of blastocyst transfers, in 43 IVF-embryo transfer candidates. Contractility was assessed on the day of human chorionic gonadotrophin (HCG) administration, 4 days after HCG (non-cavitating embryo transfer; HCG + 4), and 7 days after HCG (blastocyst transfers; HCG + 7). For this, 2 min sagittal uterine scans were obtained by ultrasound and digitized with a computerized system for the assessment of uterine contraction frequency. Our results indicated that a slight, yet significant, decrease in uterine contraction frequency, observed from the day of HCG (4.4 +/- 0.2 contractions/min) to HCG + 4 (3.5 + 0.2 contractions/min), was followed by a more pronounced, additional decrease between HCG + 4 and HCG + 7 (1.5 +/- 0.2 contractions/min; P < 0.001). In conclusion, during the luteal phase of ovarian stimulation, uterine contractility decreases progressively, and reaches a nearly quiescent status 7 days after HCG administration, at the time of blastocyst transfers. It is possible that such a uterine relaxation assists blastocyst implantation.