摘要:

The evidence that the human fetus at 15–22 weeks gestation is still immunoincompetent when judged by the generation of cytotoxic T cell responses is briefly reviewed. It suggests that it might be possible to induce immunological tolerance in the human fetus by the inoculation of allogeneic cells, thus offering a potential treatment for fetuses that have been shown to suffer from life-threatening inherited bone marrow disorders. Adult bone marrow or fetal liver thus transplanted could be expected to establish cellular chimerism and ameliorate the symptoms of the disease. Graft-versus-host disease (GVHD), brought about by mature lymphocytes present in adult bone marrow, poses the main threat. Rodent experiments have shown that GVHD can be avoided if T cell-depleted bone marrow is used in the induction of tolerance. This report summarises experiments in cynomolgus monkeys designed to test this approach rigorously by the inoculation of T-depleted paternal bone marrow cells into fetuses of different ages. Although it has become clear that tolerance can be induced there have been many in utero deaths, at least some of them from GVHD. Those fetuses that went to term were not chimeric. The possible reasons for these disappointing results are discusse

ISSN:1015-3837    

DOI:10.1159/000263327

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

A recent promising development in the field of central nervous system (CNS) transplantation has suggested the use of human fetal CNS tissue from first trimester abortions for xenografting/explantation. Such experiments would certainly expand our knowledge of the normal developmental mechanisms in human CNS, and allow studies of various indices of maturation and CNS function. However, the suggestion is looked upon with hesitance for ethical, legal and perhaps even for scientific reasons. The initial experiments have been very valuable, though, for our understanding of the structural and functional development of the human CNS, and several legal and ethical concerns have been addressed in working out the procedures for retrieving such tissue. This article tries to put our present knowledge in the right perspective of scientific achievements and potential, legal restrictions and ethical concerns.

ISSN:1015-3837    

DOI:10.1159/000263328

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The results of two French collaborative studies are reported with respect to chromosomal and biochemical analyses following the ultrasonographic detection of a fetal anomaly. Overall, chromosomal anomalies were observed in 14.8%, ranging from 8.6% in isolated single malformations to 40.5% in multiple fetal malformations associated with intrauterine growth retardation. Acetylcholinesterase (AChE) electrophoresis was performed on the amniotic fluid of 64 cases of ultrasonographically diagnosed isolated hydrocephalus. 8 cases of previously unsuspected open neural tube defects were diagnosed by AChE. Digestive microvillar enzyme assays were useful in the precise diagnosis of suspected gastrointestinal anomaly. The correlation of the results of ultrasonography and chromosomal and biochemical analyses is the basis for the diagnosis and the prognosis of pregnancy.

ISSN:1015-3837    

DOI:10.1159/000263329

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Fetal blood sampling by cordocentesis in a group of 239 severely small-for-gestational age fetuses revealed a high incidence of chromosomal anomalies (17%). Furthermore, some of the fetuses were hypoxemic and demonstrated abnormalities in carbohydrate, lipid and protein metabolism. There were significant correlations between the degree of fetal hypoxemia and abnormalities in Doppler measurements of impedance to flow in the maternal uterine arteries and in the fetal umbilical artery, and of mean blood velocity measured in the fetal descending thoracic aorta and in the common carotid artery. Maternal hyperoxygenation in some cases improved fetal oxygenation and corrected some of the abnormalities in the Doppler measurements of fetal circulation.

ISSN:1015-3837    

DOI:10.1159/000263330

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

The purpose of this investigation was to compare the efficacy of conventional ultrasonographic measurements (i.e. head to abdomen circumference ratio, amount of amniotic fluid) with Doppler ultrasonography in the differential diagnosis of small-for-gestational age (SGA) fetuses. Blood flow velocity waveforms were recorded from the umbilical artery descending aorta and internal carotid artery in 121 intrauterine growth-retarded fetuses and the pulsatility index was evaluated as an index of vascular impedance. Conventional ultrasonographic measurements were of limited usefulness in the differential diagnosis, whereas the ratio between the pulsatility indexes from umbilical and carotid arteries proved to be a good index for discriminating SGA fetuses due to low growth potential (congenital infections, strucutural anomalies, chromosomal abnormalities, constitutional factors) from those caused by placental dysfunction (specificity 96.6%, sensitivity 89%, positive predictive value 98.7%, negative predictive value 74.3% and accuracy 90.9%).

ISSN:1015-3837    

DOI:10.1159/000263331

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Since 1984 we have performed 30 intrauterine exchange transfusions (IUET) under ultrasound guidance. In 4 pregnancies with anterior placenta, we performed 9 umbilical cord catheterizations in 11 IUET: the first with material for epidural analgesia and the others with a central venous catheter. The latest one was performed at 34 weeks, the earliest at 27 weeks and repeated up to 4 times. Every catheterization did not last more than 5 min and we did not find any infection, hematoma or placental or cord injury. All 4 pregnancies were delivered at 34–36 weeks and the babies are alive and healthy (the oldest is 4 years old). This technique, when possible, is a good alternative to long procedures with risk of fetal movements, and limits the risk of hematom

ISSN:1015-3837    

DOI:10.1159/000263332

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

A review is presented of the latest data on the relationship between the blood flow velocity waveform in the lower thoracic part of the fetal descending aorta, internal carotid and umbilical artery and fetal behavioral states, in particular state IF and 2F [1], in the normal-growing and growth-retarded fetus at term. Fetal neurological development, expressed by the emergence of fetal behavior and eventually resulting in well-distinguishable fetal behavioral states, is clearly associated with specific hemodynamic adaptations. The asymmetrically growth-retarded human fetus is capable of modifying this relationship. In the analysis of blood flow velocity waveforms for clinical purposes, fetal behavioral states and fetal heart rate have to be taken into account for a proper interpretation of recorded data.

ISSN:1015-3837    

DOI:10.1159/000263333

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Over a 3-year period, 44 ultrasound-guided intravascular transfusions were performed between 18 and 32 weeks on 15 patients with severe erythroblastosis fetalis due to Rh immunization. In 4 fetuses, the first transfusion was performed before 20 weeks, in 6 between 20 and 25 weeks and in the remaining 5 between 25 and 31 weeks. Eight of the 15 fetuses were hydropic at the time of referral. Five transfusions were done in the intrahepatic umbilical vein, 6 were simple transfusions via percutaneous umbilical cord puncture, and 33 were partial exchange. There were 4 intrauterine deaths before 26 weeks, despite successfully performed tranfusions: 3 of these fetuses were severely hydropic, while in the remaining fetus hydrops had been reversed in utero. Following delivery by cesarean section at 32 weeks of gestation, 1 of the neonates developed respiratory distress syndrome and died 17 h after birth. The overall survival rate was 67% (10 of 15 cases): 4 of the 8 hydropic fetuses (50%) and 6 of the 7 nonhydropic fetuses (83%) were alive at birth and survived the perinatal period. Three of the 5 losses occurred among the first 4 cases, while in the last 11 cases the survival rate increased to 82% (9 of 11).

ISSN:1015-3837    

DOI:10.1159/000263334

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

We performed 41 intravascular ultrasound-guided fetal transfusions in a total of 20 pregnancies with erythroblastosis fetalis or alloimmune thrombocytopenia. On the basis of this experience, we developed a computer-assisted procedure for determining the volume to be transfused, which provides an adequate final concentration. Fetal weight was estimated using ultrasound measurements. Fetoplacental blood volume was estimated from the regression line: fetoplacental volume (ml) = 1.046 + fetal weight (g) × 0.14. The volume to be transfused was calculated using the simple dilution formula:Vtransfused = Vfetoplacental·(Cfinal –– Cinitial)/Ctransfused

ISSN:1015-3837    

DOI:10.1159/000263335

出版商:S. Karger AG    

年代:1988

数据来源: Karger

摘要:

Gastroschisis and omphalocele (exomphalos) are embryologically distinct, and for this reason each has its own distinct constellation of associated anomalies. The perinatal management of both gastroschisis and omphalocele addresses the controversy as to the best mode of delivery that has been expressed in the literature with regard to gastroschisis and has exercised many of those involved in antenatal diagnosis in the case of omphalocele. The post-delivery management of both of these defects is briefly discussed. Controversies surrounding the aetiology of renal dysplasia and whether urinary tract obstruction is a cause of dysplasia or an anomaly associated with dysplasia are also discussed. The options for therapy and the indications for an in utero shunting procedure are outlined as well as the controversy centred around the utility of an in utero shunt. The need for a prospective randomised trial is emphasised, together with the difficulty that is raised by the need to choose a limited number of prospective indices on which treatment decisions in such a trial must be based. The need for a long-term follow-up of all patients entered in such a trial is emphasised.

ISSN:1015-3837    

DOI:10.1159/000263336

出版商:S. Karger AG    

年代:1988

数据来源: Karger