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.     

Ring chromosome 15 syndrome

Summary Two new cases of ring chromosome 15 are reported. A review of the nine cases described in the literature shows that ring chromosomes 15 are associated with a rather uniform phenotype characterized by slight to moderate mental retardation, marked pre- and postnatal growth failure, triangular face, and short hands and feet.     

Supplementation of calves with stabilized orthosilicic acid

The bioavailability of silicon in stabilized orthosilicic acid was investigated in a double blind, placebo controlled supplementation study of calves maintained on a normal diet. The total dietary Si intake was increased by 4.9% in the form of stabilized orthosilicic acid. After 23 wk of Si supplementation, the serum Si concentration increased (p=0.0001,n=29) by 70% compared to control animals in spite of the low Si dose administered and the Si adequate diet. The individually administered Si dose was significantly associated with the serum Si concentration (r=0.44,p=0.016,n=29). The collagen concentration in dermis was significantly higher (p=0.019,n=4) in the Si group and a positive correlation (r=0.72,p=0.018,n=9) was found between the Si concentration in serum and the collagen concentration in cartilage. The calcium (Ca) and phosphorus (P) concentrations in serum were marginally higher for animals supplemented with Si compared to control animals. In serum, a significant linear relationship was found between the Si and the Ca concentration (r=0.31,p=0.019,n=59), whereas the magnesium concentration correlated marginally with the Si concentration (r=0.25,p=0.068,n=59). In summary, increasing the total dietary Si intake by 4.9% in the form of stabilized orthosilicic acid resulted in a 70% higher Si concentration in serum indicating a high bioavailability of Si in this supplement. The positive correlation between the serum Si concentration and the collagen concentration in cartilage and the serum Ca concentration, respectively, suggest the involvement of Si both in the formation of extracellular matrix components and in Ca metabolism.