Diastrophic dysplasia: A specific prenatal diagnosis by ultrasound

In a pregnant woman without increased genetic risk, the presence of distrophic dysplasia of the fetus was diagnosed sonographically at 31 weeks' gestation and definitively distinguished from other skeletal dysplasias. In all prenatal diagnoses of diastrophic dysplasia reported so far, this autosomal recessive congenital condition had occurred in the family's previous children and this made the diagnoses of fetal diastrophic dysplasia easier. The reported case was diagnosed due to evidence of an extreme shortening of all long bones of the extremities associated with other skeletal deformities which, taken as a whole, are typical of this syndrome: micrognathia, cervical kyphosis, persistent extension limitation in elbow and knee joints, club feet, ulnar diviation of hands, shortened phalanges, and, in particular, abduction of thumbs (‘hitchhiker thumbs’) and big toes.     

Two unbalanced segregation products due to a maternal t(7;16)inv(16)

We report a prenatal case of a maternally inherited abnormal chromosome 16, originally interpreted as a pericentric inversion only, but after family studies re-interpreted as a pericentric inversion (16) accompanied by an unbalanced (7;16) translocation. Because of the inversion 16 and an elder son with developmental delay and craniofacial dysmorphic features, in the past karyotyped as 46,XY, the chromosomes 16 of the mother and son were carefully re-examined. Using a whole chromosome 16 paint and sub-telomere probes of 16p and 16q, the karyotype of the mother was shown to be 46,XX,inv(16)(p11.2q23.2).ish t(7;16)(q36;p13.3)inv(16). Subsequently one chromosome 16 of the elder son appeared to be a der(16)t(7;16)(q36;p13.3). This is probably the result of a meiotic crossover between the chromosomes 16 in the mother. The prenatal karyotype was finally interpreted as 46,XY,inv(16)(p11.2q23.2).ish der(16)t(7;16)(q36;p13.3)inv(16). This is the same cytogenetic imbalance as his elder brother: a partial trisomy of chromosome 7 (q36→qter) and a partial monosomy of chromosome 16 (p13.3→pter). Copyright © 2001 John Wiley & Sons, Ltd.     

Prenatal diagnosis for arginase deficiency by second-trimester fetal erythrocyte arginase assay and first-trimester ARG1 mutation analysis

Hyperargininemia is a progressive neurometabolic disorder caused by deficiency of hepatic cytosolic arginase I, resulting from mutations in the ARG1 gene. We diagnosed arginase deficiency in a three-year-old male child of first-cousin Palestinian Arab parents. Prenatal diagnosis of an unaffected fetus was achieved in the second trimester of a subsequent pregnancy by cordocentesis and analysis of arginase activity in fetal erythrocytes. ARG1 mutation analysis in the proband revealed homozygosity for a deletion of 10 753 bp extending from the first intron to beyond the poly (A) site of the gene. This is the first gross deletion in the ARG1 gene to be identified and the first mutation to be described in an arginase-deficient patient of this ethnic origin. The identification of the ARG1 deletion in this family enabled first-trimester prenatal diagnosis in a subsequent pregnancy by multiplex PCR analysis performed on chorionic villous DNA. Copyright © 2004 John Wiley & Sons, Ltd.     

Expression of transcobalamin II by amniocytes

Children with a genetic absence of transcobalarnin 2 (TC2) are clinically asymptomatic at birth but develop severe megaloblastic anemia early in life. We have examined the incorporation of [⁵⁷Co]-CN-B₁₂ in the absence of any exogenous source of TC2 in control amniotic fluid derived cells and cultured diploid fibroblasts, and in fibroblasts from a patient with TC2 deficiency. Both control fibroblasts and arnniocytes incorporated labelled B₁₂, into TC2-B₁₂, and the proportion of labelled TC2-B₁₂ could be increased by growing cells in the presence of chloroquine which prevents intralysosomal hydrolysis of the TC2-B₁₂ complex. In contrast, fibroblasts from the patient with TC2 deficiency incorporated almost no label as TC2-B₁₂. These studies suggest that TC2 deficiency either due to aberrant production of TC2 or because of the production of an abnormal TC2 which does not bind B₁₂ can be diagnosed before birth.     

泵群无线监测系统在石化装置中的应用

介绍了机泵无线监测系统的系统架构、监测方案,并结合具体诊断案例详细说明了其在某千万吨级炼化企业的应用情况。结果表明,该系统能准确评估机泵运行状态,并及时发布报警提示和维护建议,使用该系统事后维修占比由41%降到了15%,预知性维修由不足10%上升到近50%。     

海州湾生态系统健康诊断

根据开敞海湾浅海生态系统特征,构建了包含环境现状、环境风险、环境背景、系统结构功能和系统稳定性5类诊断指标以及24个诊断因子的浅海生态系统健康诊断指标体系,并采用层次分析法对海州湾浅海生态系统2009年12月和2010年11月的健康状况进行诊断.结果表明,2009年12月和2010年11月海州湾浅海生态系统的综合健康指数值分别为0.500～0.689和0.553～0.750,浅海生态系统处于亚健康～较健康状态,近岸海域基本处于亚健康状态,离岸海域基本处于较健康状态,近岸海域生态系统健康水平低于离岸海域,这与近岸海域开发活动干扰多以及环境压力大有关.     

曳引式电梯平衡系数检测现状及发展趋势

简要介绍了曳引式电梯平衡系数的本质和意义;分析了现行的各种针对曳引式电梯平衡系数检测方法的优缺点,并对曳引式电梯平衡系数检测的未来发展趋势做出了展望。     

塔式多绳摩擦提升机振动故障源的模糊综合评判

根据塔式多绳摩擦提升机的运行特点,分析了振动原因,建立了振动故障源的模糊综合评判模型.结合对某矿井塔式多绳摩擦提升系统的振动测试结果,应用该模型对系统振动故障源进行了诊断和评判,对各种振动原因引起的系统故障的可能性给出了定量评价.实践表明,应用文中建立的模糊综合评判模型提高了塔式多绳摩擦提升机故障源诊断的客观性和准确性,为有效治理提升机的超限振动提供了可靠的理论依据,对当前老矿井改造具有一定的指导意义.     

Pericardial teratoma complicated by hydrops: successful fetal therapy by thoracoamniotic shunting

Pericardial teratoma is a potentially curable lesion that may become life threatening when it induces mediastinal compression and fetal hydrops. So far, cases with fetal hydrops have been managed by elective delivery or pericardial needle decompression. We report a case in which pericardial teratoma resulted in fetal hydrops. Following transpleural needling of the fetal pericardium at 29 weeks and 6 days, pericardial effusion decreased but hydrops persisted, while major unilateral pleural effusion appeared. A thoracoamniotic shunt was placed at 30 weeks and 5 days. Hydrops resolved, although incompletely. The baby was delivered at 32 weeks and was operated upon on day 3. This observation suggests that fetal hydrops associated with pericardial teratoma may improve following thoracoamniotic shunting. Fetal therapy may limit the risks of respiratory distress arising from the combined effect of airways compression and lung immaturity. Copyright © 2003 John Wiley & Sons, Ltd.