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61.
Early onset of autoimmunity in MRL/++ mice following immunization with beta 2 glycoprotein I.
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A L Aron M L Cuellar R L Brey S Mckeown L R Espinoza Y Shoenfeld A E Gharavi 《Clinical and experimental immunology》1995,101(1):78-81
Antiphospholipid antibodies (aPL) are associated with thrombosis, thrombocytopenia and recurrent fetal loss in humans and in some animal models. Immunization with beta 2 glycoprotein I (beta 2GPI) induced aPL production in normal rabbits and mice. However, the association of these antibodies with disease manifestations remains controversial. To determine whether induction of aPL by beta 2GPI immunization in an autoimmune strain of mice (MRL/++) would result in acceleration of clinical and serological autoimmune disease manifestations, three groups of 8-week-old female mice were studied. One group was immunized with beta 2GPI, and one with ovalbumin (OVA); the third was not immunized. After two booster injections, sera were analysed for the presence of anticardiolipin (aCL) and anti-DNA by ELISA and anti-nuclear antibody (ANA) by immunofluorescence. Mice were studied for thrombocytopenia, proteinuria, fecundity rates, litter sizes and the development of central nervous system dysfunction. Elevated levels of aCL, anti-DNA and ANA were detected in all beta 2GPI-immunized, in three OVA-immunized, and in none of the unimmunized mice. The anti-DNA antibodies were inhibited by CL micelles, suggesting cross-reactivity between aCL and anti-DNA. Platelet counts, fecundity rates and litter size were reduced in beta 2GPI-immunized but not in OVA-immunized or unimmunized mice. None of the mice developed neurological dysfunction or significant proteinuria over a 10-week period post-immunization. These findings suggest that beta 2GPI immunization induces aPL in MRL/++ mice associated with accelerated autoimmune manifestations resembling the antiphospholipid syndrome. 相似文献
62.
Hyett Jon; Moscoso Gonzalo; Nicolaides Kypros 《Human reproduction (Oxford, England)》1995,10(11):3045-3048
Pathological examination of the heart and great vessels wasperformed in 61 specimens obtained after surgical terminationof pregnancy for psychosocial indications at 918 weeksof gestation. The aorta and pulmonary trunk were identifiedand external diameters were measured at the level of, and distalto the aortic valve and pulmonary valve, the level of the aorticisthmus and thoracic aorta, and the proximal and distal ductusarteriosus. All eight vessel diameters increased linearly withgestational age and the ratio of the diameter of the aorticisthmus to that of the aortic valve or the distal ductus arteriosusalso increased with gestation. Early pregnancy is characterizedby rapid growth of the fetal head and this may well be the consequenceof a preferential distribution of left ventricular output infavour of the head due to relative narrowing of the aortic isthmusat this gestation. 相似文献
63.
C. TASHIRO MD N. INAMORI MD H. TANIGAMI MD M. NISHIMURA MD K. FUKUMITSU MD I. SHIMIZU MD 《Paediatric anaesthesia》1993,3(1):41-45
Fetal anaesthesia was performed 5 times in 1 patient to treat pleural effusions, obtain fetal blood sampling, provide albumin infusion, and establish and replace a pleuro-amniotic indwelling shunt catheter under ultrasound guidance. A maternal epidural catheter was placed and used for epidural anaesthesia for the first 4 anaesthetics. Fetal administration of pancuronium 0.15 mg·kg?1 via the umbilical vein or 0.25 mg·kg?1 intramuscularly was enough to produce immobilization without maternal effect. However, maternal pretreatment with intravenous diazepam and fentanyl was required for fetal sedation and analgesia, which was necessary for accurate and safe injection, and for suppression of fetal stress. 相似文献
64.
目的 探究多囊性肾脏发育不良胎儿的遗传学病因、影像学表现及妊娠结局。方法 回顾性分析2017年5月—2023年5月扬州大学附属淮安市妇幼保健院收治的80例多囊性肾脏发育不良胎儿的临床资料,分析其遗传学病因、影像学表现及妊娠结局。结果 80例多囊性肾脏发育不良胎儿中检出11例(13.75%)染色体异常,其中染色体数目异常1例(1.25%),10例(12.50%)存在染色体拷贝数变异(CNV)。80例多囊性肾脏发育不良胎儿中,39例(48.75%)为左侧多囊性发育不良肾,37例(46.25%)为右侧多囊性发育不良肾,剩余4例(5.00%)为双侧多囊性发育不良肾;单纯泌尿系统异常64例(80.00%),合并其他系统异常16例(20.00%),以心血管系统异常(8例)、肢体骨骼异常(3例)和、神经系统异常(3例)最常见。单纯性泌尿系统异常胎儿、合并其他系统异常胎儿的致病性CNV检出率分别为10.94%(7/64)和12.50%(2/16),差异无统计学意义(P >0.05)。单纯性泌尿系统异常胎儿中,单侧多囊性发育不良胎儿、双侧多囊性发育不良胎儿的致病性CNV检出率分别为9.84%(6/61)和33.33%(1/3),差异无统计学意义(P >0.05)。对80例多囊性肾脏发育不良胎儿进行随访,失访8例(10.00%),人工终止妊娠31例(38.75%),胎死宫内0例(0.00%),活产41例(51.25%),其中产后死亡1例(1.25%)。结论 多囊性肾脏发育不良胎儿采用染色体微阵列分析技术可提高遗传学检出率,影像学检查在多囊性肾脏发育不良诊断中具有一定价值,可为多囊性肾脏发育不良胎儿的产前诊断、遗传咨询、预后评估提供依据。 相似文献
65.
Treloar SA Sadrzadeh S Do KA Martin NG Lambalk CB 《Human reproduction (Oxford, England)》2000,15(1):55-59
In a twin sample where duration of gestation can be controlled, a specific example of the fetal origins hypothesis concerning association between low birth weight and early age at menopause is explored. The hypothesis is based on the physiologically plausible path from intrauterine growth retardation and reduced numbers of primary follicles to an earlier menopause. The sample comprised 323 Australian female twin pairs where both co-twins had reached menopause naturally and reported on their weight at birth. Regression analysis showed no linear association between the two variables (P = 0.371, r(2) = 0.0009). Intra-pair differences in age at menopause were investigated in the context of relative birth weight of co-twins. In 265 pairs an intra-pair birth weight difference was reported. In monozygotic (MZ) pairs (n = 168) this allowed for control of genetic effects as well as gestation duration. No significant differences dependent on birth weight relative to co-twin were found for age at natural menopause in either MZ or dizygotic (DZ) twin pairs, even in pairs whose birth weights differed markedly. There was some indication that twins with premature ovarian failure were heavier at birth than twins with normal or later menopausal age. We conclude that the hypothesis that lower birth weight is associated with earlier menopause is not supported by our data. 相似文献
66.
Michael S. Watson W. Roy Breg John C. Hobbins Maurice J. Mahoney 《American journal of medical genetics. Part A》1984,19(4):805-813
Cytogenetic studies on fetal blood cells obtained at 18–25 weeks gestation have provided information for decision making in 25 cases identified as being at high risk of having an abnormal fetus. In particular, in the 21 cases studied to consider the possibility of true mosaicism, confirmation in fetal blood was obtained in three, one of which presented as a pseudomosaic on the original amniotic fluid cell study. Fetal blood was also informative in two cases (one positive and the other negative) in which a diagnosis of the fragile X syndrome was being considered. Furthermore, when high risk pregnancies presented late in gestation (21–24 weeks), these methods allowed for a rapid cytogenetic diagnosis. The procedure has proved useful in most of these cases since the couples involved had indicated that they would probably have terminated the pregnancy without the reassurance of normal fetal lymphocyte studies. Since the technique carries a much higher risk of pregnancy loss than does amniocentesis, its use should only be considered when there are compelling indications. 相似文献
67.
The pre-B cell receptor (preBCR) plays critical roles in early B cell differentiation. It has been shown that not all muH chains are capable of pairing with surrogate light (SL) chains to form preBCR. Here, we established a novel system to differentially identify two types of early pre-B cell populations in bone marrow and fetal liver of mice, one producing SL-pairing muH chains and the other producing SL-non-pairing muH chains. The former population accounted for 80% of all the early pre-B cells in adult bone marrow, while it accounted for only 20% of those in fetal liver. Comparison of the two types of pre-B cell populations in fetal liver revealed the structural difference between SL-pairing and -non-pairing muH chains encoded by the V(H)81X segment that was most frequently utilized in fetal liver pre-B cells but rarely expressed by B cells generated in adults. PreBCR played an important role in the positive selection of V(H)81X-muH chains carrying the characteristic sequences of the complementarity-determining region 3 with little or no nibbling or N nucleotide addition, leading to their predominance in neonatal splenic B cells. These fetal-type V(H)81X-muH chains were also detected in adult spleen, but almost exclusively in marginal zone (MZ) B cells in contrast to the adult-type V(H)81X-muH chains. This strongly suggests that neonatally generated and selected B cells expressing the stereotyped V(H)81X-muH chains are maintained in the adult MZ and could function as innate-like lymphocytes. 相似文献
68.
Gabrielle T. Lemire Éliane Beauregard‐Lacroix Philippe M. Campeau Stefan Parent Marjolaine Roy‐Beaudry Dorothée Dal Soglio Andrée Grignon Françoise Rypens Sandrine Wavrant Marie‐Ange Delrue 《American journal of medical genetics. Part A》2020,182(4):664-672
Our objectives were to describe fetal cases of vertebral defects (VD), assess the diagnostic yield of fetal chromosomal analysis for VD and determine which investigations should be performed when evaluating fetal VD. We performed a retrospective chart review for fetuses with VD seen between 2006 and 2015. Cases were identified from CHU Sainte‐Justine's prenatal clinic visits, postmortem fetal skeletal surveys, and medical records. Cases with neural tube defects were excluded. Sixty‐six fetuses with VD were identified at a mean gestational age of 20 weeks. Forty‐seven (71.2%) had associated antenatal anomalies, most commonly genitourinary, skeletal/limb, and cardiac anomalies. Thirteen mothers (19.7%) had pregestational diabetes (95% CI [10.1%–29.3%]). Fifty‐three cases had chromosomal analysis. Three had abnormal results (5.6%): trisomy 13, trisomy 22, and 9q33.1q34.11 deletion. Thirty‐four (51.5%) pregnancies were terminated, one led to intrauterine fetal demise and 31 (46.9%) continued to term. Of 27 children who survived the neonatal period, 21 had congenital scoliosis and 3 had spondylocostal dysostosis. Seven had developmental delay. In conclusion, prenatal evaluation of fetuses with VD should include detailed morphological assessment (including fetal echocardiogram), maternal diabetes screening, and chromosomal microarray if non‐isolated. Our findings provide guidance about management and counseling after a diagnosis of fetal VD. 相似文献
69.
Monoclonal antibodies against human granulocytes and myeloid differentiation antigens 总被引:4,自引:0,他引:4
Patrice Mannoni Anna Janowska-Wieczorek A. Robert Turner Locksley McGann Jean-Michael Turc 《Human immunology》1982,5(4):309-323
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis. 相似文献