Fetal presentation of morquio disease type A

A fetus with mucopolysaccharidosis type IV A (Morquio type A) is described. The family had one affected child exhibiting symptoms of classical Morquio A disease, and late in the subsequent pregnancy prenatal diagnosis was requested. At 23 weeks' gestation, moderate ascites was detected by detailed ultrasound scan and keratan sulphate was found in the amniotic fluid. The pregnancy was terminated by prostaglandin induction and the diagnosis of mucopolysaccharidosis type IV A was confirmed by demonstration of a deficiency of N-acetylgalactosamine-6-sulphate (GalNac-6-S) sulphatase in cultured amniotic cells and in post-mortem fibroblast cultures. The activities of β-galactosidase and arylsulphatase A were normal, ruling out Morquio disease type B and multiple sulphatase deficiency. These results indicate that mucopolysaccharidosis IV A (a disease that predominantly affects the skeletal system) may produce ascites in the fetus to such an extent that it can be detected by ultrasound.     

Twin–twin transfusion syndrome—possible roles for doppler ultrasound and amniocentesis

A 29-year-old woman was referred for suspicion of twin-twin transfusion syndrome (TTTS). Several ultrasonographic and neonatal criteria of TTTS were encountered in this twin pregnancy. The peculiar observations in this case were, firstly, the demonstration of superficial anastomosis by Doppler ultrasound and, secondly, that one single therapeutic amniocentesis could have been sufficient to partially correct the progression of the syndrome, as after amniocentesis it was no longer possible to demonstrate the vascular communication. This observation suggests that superficial anastomoses could also have a role in the genesis of TTTS. Their effect could be monitored by Doppler ultrasound and could be more easily corrected by therapeutic amniocentesis.     

Prenatal echocardiographic diagnosis of right atrial isomerism

A prenatal diagnosis of right atrial isomerism is often inferred through the recognition of a constellation of cardiac anomalies on the four-chamber view or by the detection of visceral heterotaxy and asplenia. However, the actual occurrence of discordance between the arrangement of the atria and thoracic and abdominal organs makes the identification of the morphology of both atrial appendages the only reliable way to make a final diagnosis of atrial isomerism. Three cases of right atrial isomerism with visceral heterotaxy and a complex cardiac defect, diagnosed in utero by cross-sectional and colour flow Doppler echocardiography, are reported. In all the patients, the right atrial isomerism was associated with an atrioventricular septal defect, a single aortic outlet from the right ventricle, and total anomalous venous return. The diagnosis of right atrial isomerism, always confirmed by neonatal re-evaluation and/or by post-mortem examination, was made through identifying two pyramidal atrial appendages in an echocardiographic transverse plane at the level of the atria and of the origin of the great arteries. This report demonstrates that a final intrauterine diagnosis of atrial isomerism is possible, whatever the visceral situs is.     

Chorionic mosaicism: Association with fetal loss but not with adverse perinatal outcome

Cytogenetic data from the United States NICHD collaborative study of chorionic villus sampling (CVS) were used to evaluate the clinical significance of chorionic mosaicism. The 10 754 patients with normal cytogenetic results were compared wtih 108 patients (1.0 per cent) with placental mosaicism and 181 patients (1.6 per cent) with pseudomosaicism. Of the pregnancies intended to continue, the pregnancy loss rate was significantly greater in patients with placental mosaicism than in the cytogenetically normal cohort (8.6 vs. 3.4 per cent, p <0.05). However, there was no difference in the frequencies of abruptio placenta, preterm labour or delivery, small-for-gestational-age newborns, pregnancy-induced hypertension, or neonates with Apgar scores less than 7.     

Early transvaginal sonographic diagnosis of alobar holoprosencephaly

Holoprosencephaly is a cerebral anomaly resulting from incomplete cleavage of the primitive prosencephalon or forebrain. Early detection of this anomaly is very important since the most severe form is incompatible with life. The diagnosis also signals the need for a chromosomal determination since chromosomal abnormalities have been associated with this anomaly. An early diagnosis of alobar holoprosencephaly at 14 weeks' gestation, employing transvaginal sonography, is reported. Our findings are compared with prenatal transabdominal sonographic findings of holoprosencephaly which have been reported during the last decade in the literature.     

Prenatal identification of a 45,X/46,Xder(Y) mosaicism and confirmation by high resolution cytogenetics and fluorescence in situ hybridization

A 45,X/46,Xder(Y) mosaicism detected prenatally was shown to have a rare Y inversion- duplication or Y/Y translocation which can only be identified by a combination of high resolution cytogenetics and fluorescence in situ hybridization. The present data indicate the usefulness and importance of chromosome-specific probes in the identification and characterization of chromosome rearrangements.     

Prenatal diagnosis of familial ring 21 chromosome

Ring chromosome 21 is a rare chromosome anomaly often associated with mental retardation and dysmorphic features. Less commonly, the ring chromosome can be familial and associated with a normal phenotype. Phenotypically normal female carriers, however, are at increased risk of having children with Down syndrome, mosaic monosomy 21, and variable duplication or deletion of chromosome 21. Because of the relative mitotic and meiotic instability of ring chromosomes, abnormal cytogenetic findings encountered during prenatal diagnosis may not reflect the true genetic status of the fetus. This is a report of a phenotypically normal female carrier of a familial ring 21 chromosome. Prenatal diagnosis on her twin pregnancy revealed a mosaic 46,XX,r(21)(p13;q22) (77 per cent)/45,XX, – 21 in one fetus and a normal male karyotype in the second. The pregnancy was carried to term. Both infants are completely normal, with a non-mosaic ring 21 karyotype from the lymphocytes of one twin. The diagnostic uncertainty and problematic genetic counselling related to fetal cytogenetic abnormalities are the subjects of this report.     

Early genetic amniocentesis and its relationship to respiratory difficulties in paediatric patients: A report of findings in patients and matched controls 3–5 years post-procedure

This study evaluates the long-term pulmonary complications of 25 children from a prospective, matched-control, pilot study evaluating short-term complications of early (11–14 weeks' gestation) versus traditional (15 weeks' gestation and later) genetic amniocentesis. Five children in the early amniocentesis group were found to have various respiratory difficulties, a morbidity rate comparable to that of paediatric patients in the general population. These data identify the need for larger, multicentre trials.     

Kinetic adsorption of application of carbon nanotubes for Pb(Ⅱ) removal from aqueous solution

The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(Ⅱ) reached maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coeffcients from Langmuir isotherm model indicates the strong adsorptions of Pb(Ⅱ) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). The results indicates tha...