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51.
Secretory role for human uterodomes (pinopods): secretion of LIF   总被引:5,自引:0,他引:5  
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.  相似文献   
52.
Uterine contractility decreases at the time of blastocyst transfers   总被引:3,自引:0,他引:3  
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.  相似文献   
53.
BACKGROUND: It has been reported that ceasing the administration of gonadotrophin-releasing hormone (GnRH) agonist causes a profound suppression of circulating serum gonadotrophins. A comparative prospective and randomized study was conducted to investigate the effect of continuous administration of GnRH agonist during the luteal phase in an ovarian stimulation programme for IVF. METHODS: GnRH agonist was administered intranasally from the midluteal phase of the previous cycle, and pure FSH administration started on cycle day 7. In the continuous-long protocol (cL) group (n = 161 ), GnRH agonist administration was continued until 14 days after oocyte retrieval. In the long protocol (L) group (n = 158 ), GnRH agonist was administered until the day before human chorionic gonadotrophin (HCG) administration. RESULTS: The implantation rate and live birth rate per unit of transferred embryos were significantly higher in the cL group than the L group (P < 0.05 ). Serum LH and FSH concentrations on the day of, and 1 day after, HCG administration were significantly lower in the L group than the cL group (P < 0.01 ). CONCLUSIONS: Continuation of GnRH agonist administration during the luteal phase might facilitate implantation, and prevent the profound suppression of serum gonadotrophins.  相似文献   
54.
胚胎植入是生殖过程中最关键的步骤之一,植入失败的胚胎无法继续发育,是导致不孕的重要原因之一。胚胎植入的成功依赖于子宫内膜的高容受性和具有植入能力的胚胎。自噬是细胞质、细胞器和内含物被双膜囊泡吸收并运输到溶酶体进行降解和再循环的过程,是一种维持内环境稳态的方式。大量证据表明,自噬在胚胎植入的各个环节有着重要的作用。基于此探讨了自噬与子宫内膜容受性和胚胎植入能力的关系,并根据最新的研究进展,梳理了大黄素、梓醇、芍药苷、白藜芦醇、叶酸、玉米赤霉烯酮、姜黄素、汉黄芩素、槲皮素、白杨素、小檗碱、芹菜素、菲西汀、山柰酚在内的14种中药单体调控自噬干预胚胎植入的不同环节的5个机制,包括促进子宫内膜基质细胞蜕膜化、促进细胞凋亡、调节激素水平、协调炎症、促进排卵,希望对今后中药单体提高胚胎植入的成功率提供参考及思路。  相似文献   
55.
不同材料双J管对兔输尿管的影响   总被引:10,自引:1,他引:9  
目的:观察不同材料双J管对兔输尿管的影响。方法:本实验通过三种双J管置于15例(每一种双J管5例)正常兔的输尿管内,6周后观察其对输尿管上皮的损伤,输尿管的反应变化,双J管长壳的程度,置管前后肾盂压力的变化,结果:三种双J管均产生上皮细胞的损伤,二种国产双J管所引起的输尿管反应性较小。而进口双J管较重,与之相反,国产双J管长结古石的程度远较进口双J管严重(P<0.05),置管6周后与管前比较肾盂压力无明显变化(P<0.05),结论:国产双J管有较严重的长结石的倾向,但输尿管的反应性变化较小,适合于短时间置管,进口双J管的输尿管反应性变化较重,便有较长长结石倾向,比较适合于篚置管,尽管这些为动物实验所得结果,但也可能与临床有关系。  相似文献   
56.
Endometrial receptivity and implantation are important topics in reproductive sciences. No evidence was found to support sperm involvement in endometrial receptivity and its associated factors. This study aimed to explore the effect of the normal human spermatozoa–endometrium cell interaction in regulating genes in the endometrial receptivity pathway. Semen samples were collected from a healthy and fertile man; then, they were incubated with endometrial cells for 24 hr and considered as the sperm group. A group was cultured without spermatozoa and considered as a control group. About 24 hr later, cells were collected from the bottom of the culture dish. The expressions of the VEGF, FGF2, HBEGF, LIFR, EGF, LIF, MUC1, HOXA10, CSF and PGR genes were evaluated in the two groups. Statistical analysis was performed using an independent sample test. Compared with the control group, in the sperm group, the mRNA levels of PGR (p = .0451), VEGF (p = .0101), HBEGF (p = .0163), EFG (p = .0339), FGF2 (p = .012), LIF (p = .0324), LIFR (p = .0321) and HOXA10 (p = .0098) were significantly upregulated. The results showed that there is a need for the interaction between spermatozoa and endometrium for implantation and can be used for preparing uterine in in vitro fertilisation cycles.  相似文献   
57.
Diabetes mellitus is associated with increased risk of erectile dysfunction. Penile prosthesis implantation is an efficient therapeutic option for erectile dysfunction, but not without risk, as infection remains a prominent concern. This study investigates diabetes mellitus as a risk factor for penile prosthesis implantation infection and the relationship between haemoglobinA1c levels and infection rates. All diabetic patients with erectile dysfunction who underwent penile prosthesis implantation surgery between January 2012 and November 2019 at Hamad Medical Corporation, Qatar, were included in this retrospective observational study. A total of 599 diabetic patients with erectile dysfunction had penile prosthesis implantation. Mean age was 59.69 ± 31.19. Penile prosthesis implantation infection rate was 0.83% (5/599), while the mean haemoglobinA1c level was 7.58 ± 1.45 mmol/l (range: 4.1–12.6). A comparison between diabetic patients with penile prosthesis implantation infection and those without infection revealed no significant difference in the level of haemoglobinA1c between the two groups with mean haemoglobinA1c in patients with infected implants 7.14 and 7.59 for noninfected (p = 0.491). Limitations include retrospective single-centre design and low-infection rates reducing sample number. Penile prosthesis implantation infection rate in a large series of diabetic patients was low with no significant association between haemoglobinA1c level and penile prosthesis implantation infection observed.  相似文献   
58.
We present a case of a neonate with trisomy 21, ductal-dependent aortic coarctation, and severe respiratory failure secondary to coronavirus disease 2019 (COVID-19) pneumonia. The neonate was managed with venoarterial extracorporeal membrane oxygenation (VA ECMO), palliative stenting of the coarctation, and a vascular plug occlusion of a large patent ductus arteriosus. The patient was successfully weaned off extracorporeal membrane oxygenation (ECMO). The patient is currently awaiting a definitive surgical repair in the near future.  相似文献   
59.
60.
Embryo transfer (ET) is the last stage of extracorporal fertilization during which the embryo is placed in the uterine cavity with a medium-filled catheter 2–3 days after in vitro fertilization. While fertilization in the laboratory occurs at very high rates (>:90%), the overall success of the procedure (i.e., take home baby) is still very low (<25%) and assumed to be mainly due to implantation failure. A computational model was developed to simulate ET within the uterine cavity by a fluid-filled catheter inserted into a two-dimensional channel with oscillating walls. The results showed that the speed at which the embryos are injected from the catheter dominates the procedure and controls the velocity of their transport within the uterine cavity. ET at excessively high injection speeds may lead to ectopic pregnancies, while uterine peristalsis affects transverse dispersion only during injection at low injection speeds. The presence of the catheter within the uterus does not affect flow patterns downstream of its tip. The potential risks to implantation failure due to mechanical factors involved in the ET processes are discussed. © 2003 Biomedical Engineering Society. PAC2003: 8719-j, 8710+e  相似文献   
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