High incidence of mental retardation in Turner syndrome patients with ring chromosome X formation

In this report we describe and comment the high incidence of mental subnormality in a series of 21 Turner syndrome patients with ring chromosome X, diagnosed in Leuven in the period 1965-1989. In 7 of the 21 (one third) a varying degree of mental retardation, from borderline intelligence to severe mental retardation was found. In 4 of them (18.5%) mental retardation was moderate to severe.     

The fetal phenotype in 15q2 duplication

In this report we summarize the findings in a prenatally diagnosed male fetus with 15q2 trisomy. The craniofacial findings were identical to those in liveborn patients with this type of partial autosomal trisomy. A short review of the 15q2 trisomy syndrome is presented.     

A hidden-line algorithm for graphical reconstruction of serially sectioned objects

An algorithm for hidden-line removal in graphical reconstructionsof serially sectioned biological objects is developed for PC-likecomputer configurations. The aim is to handle complicated structuresdefined by vast numbers of coordinate pairs and intersectionsbetween contours, without requiring excessive computing time.The procedure depends upon a fast searching routine for thelocalization of intersections and visibility. Received on September 8, 1987; accepted on December 21, 1987     

47,XXY karyotype in a patient with Beckwith-Wiedemann syndrome

The present report summarizes the follow-up data from birth up to the age of 14 years in a male patient with Beckwith-Wiedemann syndrome and 47,XXY karyotype.     

Reciprocal translocations and full trisomy (trisomy 18 and trisomy 21) in the offspring

In this report, we present examples of trisomy 18 and trisomy 21, both resulting from maternal reciprocal translocations: 46, XX, t(5;18) (q21;q11) and 46, XX, t(5;21) (p11.2;p11), respectively.     

Renal excretion of perfluorooctanoic acid in male rats: Inhibitory effect of testosterone

There is a marked sex difference in the whole-body elimination of perfluorooctanoic acid (PFOA) in rats, with females excreting the perfluorinated acid much more rapidly (half life [t_1/2] < 1 day) than males (t_1/2=15 days). Our objective was to determine if androgens or estrogens are involved in causing this sex difference in PFOA elimination. Castration of males greatly increased the elimination of [1-¹⁴C]PFOA (9.4 μmiol/kg, i.p.) in urine, demonstrating that a factor produced by the testis was responsible for the slow elimination of PFOA in male rats. Castration plus 17β-estradiol had no further effect on PFOA elimination whereas castration plus testosterone replacement at the physiologic level reduced PFOA elimination to the same level as rats with intact testes. Thus, in male rats, testosterone exerts an inhibitory effect on renal excretion of PFOA. In female rats, neither ovariectomy nor ovariectomy plus testosterone affected the PFOA urinary elimination, demonstrating that the inhibitory effect of testosterone on PFOA renal excretion is a male-specific response. Probenecid decreased the high rate of PFOA renal excretion in castrated males but had no effect on male rats with intact testes. We conclude that testosterone is a key determinant of the sex difference in PFOA elimination in rats.     

Interstitial deletion of the short arm of chromosome 2 in a moderately mentally retarded boy without gross clinical stigmata

Summary This report describes a moderately mentally retarded boy in whom there is interstitial deletion of the short arm of chromosome 2 (del(2)(p11p21)) associated with the presence in all cells of a small acentric fragment.