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1.
The brain has long been considered an immunologically privileged site. Tissue transplanted to the central nervous system (CNS) is immunologically better tolerated than grafts to other regions of the body. With improved graft survival, tissue transplantation may provide new treatment options for previously incurable CNS disorders. The normal immune response is reviewed, followed by a discussion of the factors responsible for graft rejection. The modification of these factors to allow successful CNS transplantation is discussed.  相似文献   

2.
Buhi WC  Alvarez IM 《Theriogenology》2003,60(2):225-238
At estrus, the oviduct undergoes endocrine-induced changes which provide an essential microenvironment for maturation of gametes, fertilization and embryonic development. Several oviduct expressed proteins which interact with gametes or embryos, including the oviduct-specific, estrogen-dependent glycoprotein (OGP), have been identified and characterized. The objective of the present study was to identify, characterize and localize other proteins expressed by the porcine oviduct during estrus that may function in an autocrine or paracrine manner to enhance fertilization and embryonic development. Oviducts were collected during the estrous cycle or early pregnancy, flushed and divided into functional segments, and portions of the infundibulum, ampulla and isthmus were fixed for immunocytochemical analysis or cultured. Culture media was semi-purified by heparin-agarose affinity chromatography, proteins were transferred to polyvinylidene fluoride (PVDF) membrane after two-dimensional (2D)-SDS-PAGE and three different proteins were identified, excised and subjected to N-terminal amino acid analysis. These proteins were identified as complement component C3b, the carboxy-terminal propeptide of alpha 1 (III) procollagen (PIIICP), and the heavy chain variable region of IgA. Electrophoresis and fluorography of media from Days 0 to 12 of early pregnancy or the estrous cycle revealed both spatial and temporal expression of C3b and IgA heavy chain but not PIIICP by the oviduct. Further, all three proteins were identified in oviduct fluid by electrophoresis, immunoblot or immunoprecipitation analysis. Complement component C3b and IgA heavy chain were immunolocalized in all three oviduct segments on all days; however, temporal and spatial differences were demonstrated. Staining was greater in the infundibulum and during estrus for all three identified proteins. In summary, three proteins expressed by the oviduct at estrus and during early pregnancy were identified; characterization and localization suggest they may play a critical role in protecting the luminal environment, participating in ECM remodeling and gamete interactions.  相似文献   

3.
Antisera against particulate human glomerular basement membrane prepared from cadaver kidneys were raised in rabbits. It was shown that both normal individuals and patients with glomerular and tubular diseases excrete in their urine several antigens reactive with these antibodies. One antigen crossreacted immunologically with an antigen from human glomerular basement membrane while several others did not. One of the urinary antigens and the antigen crossreacting with the basement membrane were separated from the others by ion exchange chromatography and gel filtration, respectively.The pattern of antigen excretion differed depending on the underlying renal disease but the multitude of different antigens detected complicates the interpretation of the patterns of excretion in different diseases.  相似文献   

4.
Sub-zonal insemination (SUZI) was evaluated, in a randomized prospective study, as a treatment for certain specific types of male factor infertility. Patients were classified according to the results of an extensive semen analysis as being either IVF failure with either normal or subnormal semen quality, specific (e.g. absent outer dynein arms) or non-specific flagellar dyskinesia, or oligoasthenoteratozoospermia. SUZI was found to be an efficient technique for achieving fertilization and pregnancy for all these indications, while there was a total failure of fertilization in the control, in-vitro inseminated oocytes. A total of 395 oocytes were microinjected and 133 fertilized, among which 75 (19% overall) were diploid. More than 81% of these zygotes cleaved normally, and 31 embryo transfers resulted in seven pregnancies. However, results varied widely between the various indications, suggesting that the underlying pathology responsible for the sterility may influence gamete interaction and early embryonic development independantly of the SUZI technique.  相似文献   

5.
Antisera against particulate human glomerular basement membrane prepared from cadaver kidneys were raised in rabbits. It was shown that both normal individuals and patients with glomerular and tubular diseases excrete in their urine several antigens reactive with these antibodies. One antigen crossreacted immunologically with an antigen from human glomerular basement membrane while several others did not. One of the urinary antigens and the antigen crossreacting with the basement membrane were separated from the others by ion exchange chromatography and gel filtration, respectively. The pattern of anttigen excretion differed depending on the underlying renal disease but the multitude of different antigens detected complicates the interpretation of the patterns of excretion in different diseases.  相似文献   

6.
Summary Association of spermatozoa with blastomeres removed from the egg envelope was studied in order to investigate sperm membrane behavior under circumstances unlike those attending fertilization of normal envelope-enclosed eggs. Under the altered circumstances all parts of the surface of the sperm cell were afforded the opportunity of meeting blastomere plasma membrane. Nevertheless, in each case the spermatozoon first became activated, an acrosomal tubule formed, and it was this organelle alone which fused and established continuity with the blastomere plasma membrane. This behavior of the spermatozoon with respect to the denuded blastomere parallels the behavior of the sperm cell with respect to the envelope-enclosed egg at fertilization. Since the sperm cell behaves so similarly in two situations which are so different with respect to what the spermatozoon encounters, this behavior is considered to reflect the inherent nature of the spermatozoon, and analysis of this behavior in relation to a blastomere is considered to be valid also in relation to an egg during fertilization. It is concluded that membrane fusion, involving the acrosomal tubule of an activated spermatozoon, is the only means by which gametic union is established and that these are obligatory rather than fortuitous features of sperm-egg association in Saccoglossus. It is suggested that these features are probably obligatory also in other species which exhibit this pattern of sperm-egg association.This investigation was supported by Research Grant HD-00007 from the National Institutes of Health, United States Public Health Service.  相似文献   

7.
目的:比较分析拮抗剂方案与长方案对年轻卵巢低反应(POR)女性体外受精(IVF)新鲜移植周期临床妊娠结局的影响,以探讨拮抗剂方案的应用价值。方法:回顾性分析2014年1月至2017年6月在广东省妇幼保健院生殖中心行体外受精-胚胎移植(IVF-ET)治疗的204例妇女213个IVF新鲜移植周期的临床资料。按随机数字表法分为拮抗剂组83例(84治疗周期)与长方案组121例(129治疗周期),比较两组一般资料、实验室资料、促排卵资料及妊娠结局的差异。结果:拮抗剂组的窦卵泡计数(AFC)、抗苗勒氏激素(AMH)水平、促性腺激素(Gn)使用天数、Gn总量、HCG日雌二醇(E2)水平、HCG日内膜厚度、移植日内膜厚度、获卵数、成熟卵子数及正常受精数低于长方案组,基础FSH/LH、Gn启动量高于长方案组(P0.05),但两组优质胚胎数、移植胚胎数、移植囊胚比例、冷冻胚胎数、胚胎种植率及早期自然流产率比较均无统计学差异(P0.05)。拮抗剂组和长方案组的临床妊娠率较高,分别为58.14%和63.10%,但是两组临床妊娠率比较无统计学差异(P0.05)。结论:给予年轻POR患者两种方案均可获得较满意的IVF新鲜移植周期临床妊娠结局,拮抗剂方案获卵数较长方案少,但是其优势在于Gn使用量更少,使用时间更短。  相似文献   

8.
Two-dimensional crossed immunoelectrophoresis of sera from pregnant and non-pregnant horses, using antisera developed against early pregnant mare serum, revealed the presence of two immunologically related proteins one of which appeared to be specific to the pregnant state. This pregnancy-specific protein had beta 2-electrophoretic mobility and was first detectable at Day 6 after successful mating with a stallion. The second protein had gamma 2-electrophoretic mobility and was present in sera from pregnant and non-pregnant horses. The proteins were termed beta 2-horse pregnancy protein and gamma 2-horse protein respectively. The latter appeared to be immunologically related to the former in that the precipitin lines of the 2 proteins showed continuity. Samples from 16 mares mated with a stallion were investigated for the beta 2-protein during the first 3 weeks after mating. Of the 11 successful matings, confirmed by ultrasonic scanning at 90 days or by a successful outcome, 10 mares showed the presence of the protein. In all of 14 non-pregnant sera taken from mares not recently mated, the protein was not detectable. The validity of detection of beta 2-protein as an indication of pregnancy was clinically significant at the 10% level. The presence of the protein in 2 out of the 5 recently mated mares that did not become pregnant may be indicative of a biochemical pregnancy that failed at a later stage of gestation.  相似文献   

9.
Canine X-linked severe combined immunodeficiency (XSCID) is due to mutations in the common gamma chain (gammac) gene and is identical clinically and immunologically to human XSCID, making it a true homologue of the human disease. Bone marrow-transplanted (BMT) XSCID dogs not only engraft donor T cells and reconstitute normal T-cell function but, in contrast to the majority of transplanted human XSCID patients, also engraft donor B cells and reconstitute normal humoral immune function. Shortly after our initial report of successful BMT of XSCID dogs, it soon became evident that transplanted XSCID dogs developed late-onset severe chronic cutaneous infections containing a newly described canine papillomavirus. This is analogous to the late-onset cutaneous papillomavirus infection recently described for human XSCID patients following BMT. Of 24 transplanted XSCID dogs followed for at least 1 year post-BMT, 71% developed chronic canine papillomavirus infection. Six of the transplanted dogs that developed cutaneous papillomas were maintained for >3 1/2 years post-BMT for use as breeders. Four of these six dogs (67%) developed invasive squamous cell carcinoma (SCC), with three of the dogs (75%) eventually developing metastatic SCC, an extremely rare consequence of SCC in the dog. This finding raises the question of whether SCC will develop in transplanted human XSCID patients later in life. Canine XSCID therefore provides an ideal animal model with which to study the role of the gammac-dependent signaling pathway in the response to papillomavirus infections and the progression of these viral infections to metastatic SCC.  相似文献   

10.
The egg's blocks to polyspermy (fertilization of an egg by more than one sperm) were originally identified in marine and aquatic species with external fertilization, but polyspermy matters in mammalian reproduction too. Embryonic triploidy is a noteworthy event associated with pregnancy complications and loss. Polyspermy is a major cause of triploidy with up to 80% of triploid conceptuses being the result of dispermic fertilization. The mammalian female reproductive tract regulates the number of sperm that reach the site of fertilization, but mammals also utilize egg‐based blocks to polyspermy. The egg‐based blocks occur on the mammalian egg coat (the zona pellucida) and the egg plasma membrane, with apparent variation between different mammalian species regarding the extent to which one or both are used. The zona pellucida block to polyspermy has some similarities to the slow block in water‐dwelling species, but the mammalian membrane block to polyspermy differs substantially from the fast electrical block that has been characterized in marine and aquatic species. This review discusses what is known about the incidence of polyspermy in mammals and about the mammalian membrane block to polyspermy, as well as notes some lesser‐characterized potential mechanisms contributing to polyspermy prevention in mammals.  相似文献   

11.
Cell-mediated immune responses to Tamm-Horsfall glycoprotein isolated from human urine were investigated using the leucocyte migration test. Abnormal responses were found in 91% of patients with active chronic hepatitis or primary biliary cirrhosis with an associated renal tubular acidosis (R.T.A.) but in only 19% of those without R.T.A. In nearly all of a group of patients without autoimmune liver disease and in a control group of normal subjects results were within normal limits. In addition, using an immunofluorescent technique with rabbit antibody to human Tamm-Horsfall glycoprotein, it was possible to show the presence in human liver cell membrane of material reacting immunologically as Tamm-Horsfall. These findings suggest that the development of an immune response to this glycoprotein, initiated by release of cross-reacting antigens from damaged hepatocytes, could be the mechanism underlying the occurrence of R.T.A. in some patients with autoimmune liver disease.  相似文献   

12.
The effect of neonatal thymus grafts implanted in nude mice previously transplanted with three different human malignant tumors - an adenocarcinoma of the colon, a malignant melanoma and a Burkitt's lymphoma - were studied. In all immunologically reconstituted animals tumord were rejected. Tumor rejection stated 2-3 weeks after thymus implantation, and was completed after 30-6 weeks. Histological examination of lymphoid tissues showed a correlation between immunological reconstitution and tumor rejection. The rejection process showed a characteristic histologic picture with 3 phases - an early, an intermediate and a late phase - these were similar in the three tumor types examined. The possible mechanisms of reconstitution and tumor rejection are discussed.  相似文献   

13.
The egg of the medaka, Oryzias latipes, was impaled with two microelectrodes so that its membrane potential could be clamped at a constant level during fertilization. Fertilization occurred at all membrane potentials between ?80 and +48 mV. Therefore, there is apparently no electrical block to polyspermy in this egg. In 16 of these eggs the membrane potential was also clamped at a constant level during the 6- to 14-min period after fertilization and the eggs' subsequent development was studied. All of these eggs developed normally up to at least the beating heart stage. Therefore, the fertilization potential is not necessary for further development. When the egg is clamped at levels more negative than ?25 mV, the injected clamping current is usually biphasic just after fertilization with an inward current phase preceding a longer outward phase. The inward current phase corresponds well in time with the membrane depolarization normally triggered by fertilization. The outward current phase was observed in all eggs studied and the more positive the holding potential, the longer was the outward current duration.  相似文献   

14.
The obligatory role of the jelly coat for maximal transport of all amino acids, including those found to be jelly coat-independent in Xenopus laevis embryos, has been shown in Bombina orientalis embryos. Amino acid transport in dejellied embryos (without fertilization membrane and jelly coats) of Bombina, reconstituted with either intact or homogenized jelly coats, was similar to the values in normal embryos. Amino acid transport in totally dejellied embryos, and those surrounded with fertilization membrane only, was similar. Reconstitution of dejellied embryos with physically denatured jelly coats did not restore full amino acid transport. Amino acid transport values using heterologous combinations of dejellied embryos and jelly coats of Bombina orientalis and Xenopus laevis were equivalent to those in homologous combinations.  相似文献   

15.
在纯化猪肝微粒体磷脂酰肌醇-4-激酶(PI-4-K)的基础上,制备该酶的免疫血清、提纯IgG,并建立了PI4-K的ELISA,进行不同组织中PI4-K的免疫沉淀分析和免疫定量。结果证明:猪肝微粒体PI4-K的抗血清或抗体IgG可沉淀猪肾和猪肺的微粒体膜、猪肝细胞膜和人中性粒细胞细胞膜TritonX-100增溶液(TXSM)中的PI4-K,表明不同组织、不同亚细胞器和不同种属的PI4-K有相似的抗原性。猪肝、肾、肺、胃、小肠和大肠TXSM中PI4-K的活力和酶蛋白含量相仿,急性中性粒细胞白血病患者的中性粒细胞膜上PI4-K的含量和活力都增加3.5倍左右.加上PI4-K抗体沉淀各组织PI4-K活力和酶蛋白的百分率基本相同,支持文献报道组织中微粒体或细胞膜中的PIK主要是PI4-K,而免疫性不同的PI3-K含量极少的观点.  相似文献   

16.
摘要 目的:探讨子宫内膜容受性检测(ERT)技术在反复种植失败患者冻融胚胎移植(FET)中的应用价值,并分析其临床妊娠的影响因素。方法:回顾性分析2019年10月~2022年4月期间海南省妇女儿童医学中心收治的150例反复种植失败患者的临床资料,根据是否接受ERT技术分为ERT组(n=78,接受ERT技术)和无ERT组(n=72,未接受ERT技术)。按照反复种植失败患者是否临床妊娠分为临床妊娠组和未临床妊娠组。采用单因素和多因素Logistic回归模型分析临床妊娠的影响因素。结果:两组异位妊娠率组间对比未见统计学差异(P>0.05)。ERT组临床妊娠率、活产率高于无ERT组,移植日内膜厚度大于无ERT组,移植胚胎数少于无ERT组,流产率低于无ERT组(P<0.05)。所有患者按照是否临床妊娠分为临床妊娠组(n=85)和未临床妊娠组(n=65)。单因素分析结果显示:临床妊娠与年龄、移植胚胎类别、移植胚胎数量、总周期数、FSH、子宫内膜厚度、子宫内膜类型有关(P<0.05),而与体质量指数(BMI)、不孕年限、不孕类型、胚胎冷冻保存时间无关(P>0.05)。多因素Logistic回归分析结果显示:年龄偏大、FSH偏高是临床妊娠的危险因素,而移植胚胎类别为囊胚、移植胚胎数量偏多是临床妊娠的保护因素(P<0.05)。结论:ERT技术用于反复种植失败患者FET中,可有效改善患者的临床妊娠。年龄、FSH、移植胚胎类别、移植胚胎数量是临床妊娠的影响因素。  相似文献   

17.
以蕨类模式植物水蕨(Ceratopteris thalictroides L. Brongn.)为供试材料,设置不同质量浓度布雷菲德菌素A(BFA)分别处理10、20、30 h,采用光学显微镜和电镜对其树脂切片进行了观察;在此基础上,进行高碘-酸锡夫反应(PAS)和苏丹黑B反应。结果显示:对照组(未经BFA处理)发育卵中期的水蕨卵细胞较大,核仁呈圆形,细胞内高尔基体、内质网等细胞器完整;卵细胞和腹沟细胞间的受精孔清晰可见,二者间的分离腔内仅有极少量的泡状分泌物;卵膜较厚,有明显的层次。而处理组卵细胞的受精孔和卵膜不典型,由数量较多、大小不一的囊泡组成;受精孔下方有较多的线粒体和少量的高尔基体分布;高尔基体、内质网等膜性细胞器已断裂;细胞核上方和卵膜下方均分布着大量的嗜锇性囊泡,分离腔中充满了絮状物质。组织定位显示:对照组的分离腔较空,而处理组分离腔内充满着多糖类物质。综上所述,BFA会对卵细胞中的内质网和高尔基体等膜性细胞器造成破坏,影响分泌系统的正常功能,进而影响卵膜及受精孔的形成。本研究结果为进一步探索受精孔形成的机制以及蕨类植物生殖生物学的研究奠定了基础。  相似文献   

18.
Animals with extreme body growth frequently experience poor reproductive performance, but the cause for this association has not been clearly established. A line of mice homozygous for the high growth (hg) mutation, a mutation that has a major effect on post-weaning growth, exhibits several reproductive deficits including an abnormally high incidence of luteal failure. The objective of the present study was to investigate luteal failure in high-growth (HG) mice during pregnancy and to determine whether the cause of the apparent luteal failure resides in the ovary or the hypothalamic-pituitary unit. In HG females with a demonstrated history of infertility, progesterone injections (1 mg s.c. daily) beginning on Day 1 postcoitum (p.c.) increased the proportion of animals pregnant at Day 17 of gestation. Twice-daily injections of 100 microgram of ovine prolactin (PRL) in alkaline saline given to another group of females beginning on Day 1 p.c. increased the proportion of HG females that were pregnant on Day 6 of gestation compared with saline-injected HG females, although PRL did not increase the pregnancy rate in HG females when compared with a group of noninjected control females. When ovaries from HG females were transplanted into ovariectomized congenic C57 hosts, the C57 graft hosts displayed normal estrous cycles, and upon mating the majority of graft hosts became pregnant. In contrast, when ovaries from C57 females were transplanted into ovariectomized HG hosts, the HG graft hosts displayed normal estrous cycles, but upon mating most were unable to maintain pregnancy. These results suggest that the hypothalamic-pituitary unit of the HG female provides an inadequate signal to the ovaries to maintain pregnancy. Luteal failure in HG females may be due to insufficient PRL as required for establishment and early maintenance of the CL during pregnancy in mice.  相似文献   

19.
By means of the immunodiffusion method it was shown that human pregnancy-specific beta-globulin, as well as analogous beta-globulins in the pregnancy serum of mammal animals (rat, guinea-pig) had an individual antigenic structure. During pregnancy the blood serum of the allied species (rat, mouse) contained immunologically similar beta-globulins which apparently were synthesized in the placenta.  相似文献   

20.
Ultrastructural changes in the plasma membrane of uterine epithelial cells in the pseudopregnant rat were examined to determine if these changes resemble those found during normal pregnancy and also to examine if the well-known membrane alterations of early pregnancy are intrinsic to uterine epithelial cells. Changes in the surface contours of uterine epithelial cells from the afternoon of day 6 to the morning of day 9 of pseudopregnancy were similar to those present after attachment in normal pregnancy although somewhat delayed. The presence of short, irregular microvilli was seen from as early as day 7 of pseudopregnancy, with regular microvilli returning to the epithelial surface by days 8-9 of pseudopregnancy but to a slightly lesser extent as compared to normal pregnancy. Furthermore, observations made on the afternoon of day 6 to the morning of day 7 of pseudopregnancy showed that the uterine lumen was closed down and that complete membrane flattening between opposing uterine epithelial cells was seen all along the uterus in the absence of a blastocyst. These observations establish that the "plasma membrane transformation" does not depend on blastocyst implantation.  相似文献   

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