Search PubMed⌕ Search

Biomedical subjects

H Rehder

Publications and source records attributed to H Rehder.

At least 37 records · Page 2Linked to original sources
PubMed1997

Neural tube defects in chromosomally normal and abnormal human embryos.

Neural tube defects (NTDs) were recognized in eight out of 91 intact embryos from spontaneous abortions and in one case of an induced abortion following prenatal diagnosis of a chromosomal disorder. Five of the nine cases showed chromosomal abnormalities. Trisomy 18 and triploidy were associated with spina bifida in three cases, trisomy 7 with parieto-occipital encephalocele and monosomy X with spina bifida and iniencephaly in one case. A sixth anencephalic embryo in which chromosomal analysis was not performed showed a malformation pattern highly suggestive for trisomy 18. Discussion focuses on the high rate and the type of chromosomal abnormalities among spontaneously aborted NTD embryos, on the contrasting phenotype of 45,X conceptions and on the morphogenesis of the different neural tube defects in early development. In view of future early endovaginal ultrasound diagnosis, the changing morphological pattern is exemplified, and ranges from apparently hyperplastic to degenerative alterations of the exposed neural tissue.

Chorionic Villi Sampling↗
PubMed1997

Cystic hygroma as an early first-trimester ultrasound marker for recurrent Fryns' syndrome.

We present a case of a fetus who at a 12-week ultrasound examination was shown to have a large cystic hygroma. Fryns' syndrome was suspected because the mother's previous pregnancy had been affected by the condition. Pathological examination confirmed the diagnosis at this early stage of gestation. In families with increased risk for Fryns' syndrome, first-trimester ultrasound screening should be offered to exclude cystic hygroma as an ultrasound marker for this most often lethal malformation.

Abnormalities, Multiple↗
PubMed1996

VACTERL with hydrocephalus and branchial arch defects: prenatal, clinical, and autopsy findings in two brothers.

VACTERL association is defined as a combination of vertebral, anal, cardiac, tracheoesophageal, renal and limb anomalies, in particular radial defects. In recent years hydrocephalus was observed in patients with apparent VACTERL association. This particular condition was recognized as a hereditary entity with poor prognosis. Both autosomal recessive and X-linked forms were described. Here we report prenatal, clinical and autopsy findings in 2 brothers with this syndrome, who had, in addition, branchial arch anomalies. The recurrence in this family suggests X-linked inheritance. Branchial arch defects have so far not been described as part of the VACTERL+H syndrome. This observation further supports that a variety of brain anomalies including hydrocephalus associated with VACTERL anomalies represents separate entities with a considerable recurrence risk. The use of the term VACTERL "association" for these conditions is misleading and is discouraged.

Abnormalities, Multiple↗
PubMed1996

Proliferation kinetics of chorionic villi in chromosomally normal and abnormal spontaneous abortions analyzed by premature chromosome condensation and northern blot.

The activity of cell proliferation in human chorionic villi (CV) obtained from early spontaneous abortions (SAB) and from elective abortions (EAB) was determined by means of premature chromosome condensation (PCC), and by Northern blot analysis of expression of proliferation antigens Ki67 and PCNA. The rate of chromosome aberrations among the SABs was 57%, while the EABs, taken as controls, were shown to be chromosomally normal. PCCs were induced by fusion of the chorionic interphase cells with mitotic Chinese hamster ovary (CHO) cells. To analyze the proliferation stages of the chorionic G1-interphases, the potential proliferation index (PPI) was ascertained. The PPI values found in SABs ranged from 36% to 97% as described for intensely proliferating tissues. They did not differ from the values found in the controls (34-90%), indicating maintenance of proliferation activity of CV cells even after death of the embryo in missed abortions. No significant PPI differences were observed between the abortion groups with different cytogenetic results. The expression of proliferation associated antigens Ki67 and PCNA showed no significant differences between mean values of the total of SABs and of the controls. However, the comparison of mean values of chromosomally abnormal with chromosomally normal SABs revealed a significantly reduced Ki67 activity in the SABs with chromosome aberrations. A similar results was obtained when comparing mean values of Ki67 and PCNA expression from trisomic SABs with those of the controls. By further subdivision of chromosome aberrations a decrease for the expression of both antigens in chorionic villi from early lethal trisomies, and a significantly increased Ki67- and PCNA-expression in triploidies became evident.

Abortion, Induced↗
PubMed1995

Parental origin of the extra haploid chromosome set in triploidies diagnosed prenatally.

The parental origin of the additional chromosome complement in a total of 17 cases of triploidy was determined mainly using highly polymorphic microsatellites. Maternal origin of the triploidy was demonstrated in most cases. To the best of our knowledge, this is the first systematic evaluation of the parental origin of chromosome sets in fetuses who survived until a cytogenetic diagnosis was established. In contrast to previous investigations this study documented a predominance of maternal origin of the extra haploid set mainly due to longer survival time for digynic triploidies. The concept of 2 distinct fetal phenotypes in triploidy is clearly supported by this study.

Adult↗
PubMed1995

Extreme hypotrophy of the lower body pole, extensive hypoplasia of the spinal column and multiple anomalies of abdominal organs: a maximal variant of the caudal regression sequence?

A newborn with extreme hypotrophy of the lower body pole and aplasia of the lower spinal column is reported. Additional anomalies of internal organs included absence of one kidney and ureter, a diaphragmatic hernia, and anal atresia. Part of the organs located in the lower body pole were necrotic. There were no excretory apertures, and external genitalia were absent. Chromosomal analysis revealed a 46,XY karyotype. The multiple anomalies seen in this newborn may be interpreted as a maximal variant of the caudal regression sequence.

Abnormalities, Multiple↗
PubMed1994

[Pathologic embryo examinations of induced and spontaneous abortions in the 1st trimester of pregnancy].

Morphological examination methods which are appropriate for detection of embryonic developmental defects are presented. The main emphasis is put on autopsy of small embryos using a dissection microscope and on documentation of the embryonic skeleton by means of skeleton staining. Through presentation of the embryopathological findings in 15 first-trimester abortion specimens we demonstrate that these examination techniques frequently allow diagnosis of isolated malformations as well as malformation syndromes, even in the fragmented or macerated embryo. Careful embryopathological examination and evaluation is a precondition for genetic counselling, as well as for goal-directed prenatal diagnostic measures in future pregnancies.

Abortion, Eugenic↗
PubMed1994

[Familial akinesia-hypokinesia sequence (Pena-Shokier phenotype)].

The Pena Shokeir phenotype (PSP) is characterised by multiple ankyloses, camptodactyly, facial dysmorphisms and lung hypoplasia with hydramnios. The basic neuromuscular defect leads, through a fetal hypokinesia-akinesia, to the development of this nonspecific phenotype and a respiratory insufficiency with early postnatal mortality. Severe central nervous anomalies are described in one-third of the reported cases. In this paper a foetus with PSP and 4 further foetuses with severe cerebral malformations and only discrete lung hypoplasia are described. It is not clear whether the cerebral malformations represent a primary or secondary developmental defect.

Abnormalities, Multiple↗
PubMed1993

Craniofacial anomalies, abnormal hair, camptodactyly, and caudal appendage (Teebi-Shaltout syndrome): clinical and autopsy findings.

Teebi and Shaltout [1989: Am J Med Genet 33: 58-60] described a new syndrome of craniofacial anomalies, abnormal hair, camptodactyly, and caudal appendage in children born to a consanguineous couple. We report on a second family with the same pattern of anomalies occurring in a liveborn female and 3 spontaneously aborted fetuses, and include autopsy findings. As additional findings 2 of our cases had unilateral microphthalmia and kidney anomalies. Our observation confirms that this pattern of anomalies is a distinct syndrome with autosomal recessive inheritance; we suggest the synonym Teebi-Shaltout syndrome.

Abnormalities, Multiple↗
PubMed1993

New autosomal recessive lethal disorder with polycystic kidneys type Potter I, characteristic face, microcephaly, brachymelia, and congenital heart defects.

We report on 3 pairs of sibs from unrelated families, who present with polycystic kidneys Potter type I claimed to be specific for the ARPKD, and with microbrachycephaly, hypertelorism with telecanthus, large posteriorly angulated fleshy ears and various congenital malformations including congenital heart defects. We suggest that they represent a previously unrecognized autosomal recessive lethal developmental disorder within the group of infantile polycystic kidney disease and Potter sequence.

Abnormalities, Multiple↗
PubMed1993

Polyploidies in abortion material decrease with maternal age.

Among 639 spontaneous abortions between the 8th and 14th week of gestation 342 (53.5%) revealed an abnormal karyotype. While the rate of trisomies distinctly increased with advancing maternal age, a decrease in the rate of 45,X conceptuses and polyploidies was observed among abortions from older women. The overall relation of XXXX:XXYY among the tetraploidies was 14:11 and that of XXX:XXY:XYY among the triploidies was 26:36:1. However, when the latter was related to maternal age, a reversal of the XXX:XXY ratio of 1:2 in the younger to 2:1 in the older age groups became evident. Furthermore a decrease in the rate of "paternally" derived partial hydatidiform moles was found among the triploid abortion specimens from older women. From these observations we conclude that digyny plays a major role in the origin of triploidy in the increased maternal age groups, while diandry related to immaturity of oocytes and impairment of oocyte cortical function is more frequent in triploid abortions from younger women.

Abortion, Spontaneous↗
PubMed1993

The insulin-like growth factor type-2 receptor gene is imprinted in the mouse but not in humans.

In mouse, four genes have been found to undergo genomic imprinting resulting in differential expression of maternally and paternally inherited alleles. To determine whether the cognate genes are also subject to imprinting in humans, we have studied allele-specific expression patterns of insulin-like growth factor 2, IGF2-receptor and H19 in human fetal and adult tissues. In keeping with previous findings in mice, our results indicate that in human fetal tissues the paternal H19 alleles is inactive. IGF2 is monoallelically expressed in various tissues but surprisingly not in adult human liver. The human IGF2R gene, another classic example of imprinting in mice, was found to be expressed from both alleles. We provide the first direct evidence for differential imprinting in the human and murine genome.

Adult↗
PubMed1993

A case of full triploidy (69,XXX) of paternal origin with unusually long survival time.

Triploidy is a rare disorder in live-born children and these infants generally die within the first hours after birth. We report here on a girl with full triploidy and multiple malformations, who survived for 10 1/2 weeks. The extra set of haploid chromosomes was of paternal origin, as shown by chromosomal banding techniques.

Abnormalities, Multiple↗
PubMed1992

Prenatal diagnosis of the Pallister-Killian mosaic aneuploidy syndrome by CVS.

Prenatal cytogenetic analysis at 11 weeks of gestation revealed an abnormal karyotype 47,XX,+mar in all metaphases obtained from a chorionic villi sample after 24 h culture. Karyotyping of amniotic fluid cells in the second trimester showed mosaicism 47,XX,+i(12p)/46,XX with 10% aneuploid cells. The pregnancy was terminated at 20 weeks of gestation on the patient's request. The aborted fetus showed typical manifestations of the Pallister-Killian mosaic aneuploidy syndrome. The identity of the supernumerary isochromosome 12p was proven by LDH isozyme electrophoresis using cultured fibroblasts and by nonradioactive in situ hybridization using a biotinylated set of chromosome 12-specific DNA probes.

Abnormalities, Multiple↗
PubMed1991

[Diagnosis of fetal virus infections by in situ hybridization].

Non-radioactive in situ hybridization of formalin-fixed paraffin-embedded placental and foetal tissue, using virus-specific DNA or RNA probes, may be helpful for the diagnosis of foetal virus infection causing foetal hydrops, granulomatous placentitis and abortion. We present four cases of intrauterine CMV-, Parvo-B19- and Varicella-Zoster virus infection, in which this diagnostic method established detection of the virus.

Adult↗
PubMed1991

No evidence of mutations in four candidate genes for male sex determination/differentiation in sex-reversed XY females with campomelic dysplasia.

Campomelic dysplasia (Cd) occurs combined with sex reversal resulting in XY females. The recent identification of candidate genes for sex determination/differentiation and of a sex determining region on the human Y chromosome prompted the authors to study these genes for mutations in patients with Cd and sex reversal. In a total of five cases, no evidence for a mutation in the genes SRY, ZFY, ZFX, MEA and some anonymous Y-linked sequences was found. In addition to Southern analysis, gene expression of ZFY, ZFX and MEA was found to be normal as well. It is concluded that sex reversal in this condition is due to mutation in a so far unidentified gene which may act secondary to the testis-determining factor (TDF).

Base Sequence↗
PubMed1991

[Tracheal agenesis, a rare cause of respiratory insufficiency in newborn infants].

Tracheal agenesis is a rare congenital anomaly which presents immediately after birth an absolute respiratory insufficency. This report describes a new-born infant with a tracheal agenesis Typ II which was combined with an esophageal atresia and distal esophagotracheal fistula. In addition, costal synostosis was found. These malformations can be added to the VATER-association. Resuscitation of our patient (orotracheal and esophageal intubation, emergency coniotomy) was unsuccessful. However, in most cases of tracheal agenesis with esophagotracheal communication primary resuscitation is possible by esophageal intubation and by application of continuous positive pressure ventilation. Diagnosis must be confirmed by immediate contrast roentgenography or endoscopy. The results of surgery are disappointing until now.

Abnormalities, Multiple↗