Astroglia disturbances during development of the central nervous system in fetuses with Down's syndrome

Down's syndrome (DS), caused by aneuploidy of chromosome 21, is the most common chromosomal disorder. The most significant symptom of this disorder is mental retardation. Neuropathological changes found in the DS central nervous system (CNS), such as reduced number of neurons, alteration of synapses and synaptic spines or delayed myelination have been widely described. But there are only a few studies of DS-related glia disturbances. A growing number of astroglia new functions have recently been described. In our study we compared the number of astrocytes and radial glial cells in the frontal lobe of DS fetuses at 18-20 weeks of gestation with that observed in age-matched controls. We found a substantially increased number of glial fibrillary acid protein (GFAP) positive cells in all age range samples of DS brains. We also noticed that in our study astrocytes in DS brains seem to be morphologically more mature than in controls of corresponding age. The same observation was made for radial glia. Taking into consideration the role played by astroglia during CNS development we believe that any change in their number, reduced or increased, can affect CNS development and lead to disturbances of both neurogenesis and synaptogenesis. A possible correlation between the increased number of astroglia and disturbances in CNS development is discussed.     

Cystathioninuria in Down's syndrome

ABSTRACT. Secondary Cystathioninuria is associated with various pathological conditions (Gjessing, 1963; Gjessing & Mauritzen, 1965; Endres & Wuttge, 1978). In many cases, Cystathioninuria has been associated with mental retardation (Harris el al., 1959; Robb et al. , 1984). As far as the authors know, Cystathioninuria has not previously been described in Down's syndrome. In 1981, in the authors' institution for the mentally retarded, all patients with Down's syndrome were screened with regard to aminoaciduria, using thin layer chromatography. In the course of this process, a case of Cystathioninuria was discovered. The results are presented in detail.     

Ocular findings in Down's syndrome

ABSTRACT. This communication presents the ocular findings in 30 patients with Down's syndrome residing in a central institution for the mentally retarded. The findings have been compared to those in matched controls consisting of mentally retarded people from the same institution. The ocular status in patients with Down's syndrome has been extensively studied previously, and to a large extent, findings in previous materials were confirmed. However, in this institution, which consisted of adult patients only, some unusual findings have also been made: nine of the 30 patients had keratoconus, which is a remarkably high figure. A compilation of data shows that only one of the patients with Down's syndrome had nearly normal ocular status.     

Hydrocephalus in Down's syndrome.

An infant with hydrocephalus, aqueductal stenosis and partial agenesis of the corpus callosum in association with Down's syndrome is reported. Review of the literature reveals that hydrocephalus is infrequent in Down's syndrome. Of special interest is the occurrence of agenesis of the corpus callosum in our patient, a lesion often reported with other chromosomal abnormalities, but not previously observed in Down's syndrome.     

Multi-infarct dementia in Down's syndrome

ABSTRACT. In spite of a burgeoning literature on the association of Down's syndrome with Alzheimer's disease, the occurrence of multi-infarct dementia has largely been overlooked. A 55-year-old woman with Down's syndrome in whom a dementing process was associated with evidence of significant cerebrovascular disease is reported here. It is considered that she sustained both multi-infarct dementia and probable Alzheimer's disease. It is suggested that such cases are under-reported     

Atlanto-occipital instability in Down's syndrome

ABSTRACT. A patient with Down's syndrome and asymptomatic atlanto-occipital instability is described. The relationship between atlanto-occipital instability, atlanto-axial instability and generalized ligamentous laxity, is discussed.     

Down's syndrome and thyroid disorder

ABSTRACT. The thyroid status of 106 adults with Down's syndrome was assessed. Six were previously diagnosed as hypothyroid and were already receiving thyroxine. A further 37 patients showed abnormal thyroid function. Biochemical evidence of hypothyroidism (T4 < SO nmol/1 and T.S.H.>4 mu/<) was found in one person. Six patients were found to have an unequivocally elevated T.S.H. but normal T4 (T4>50 nmol/l and T.S.H.>20 mu/1) and 29 were found to have a modest elevation of T.S.H. but normal T4 concentration (T4>50 nmol/1 and T.S.H. between 4 and 20 mu/l). There was one patient with milJ thyroloxicosis (T4= 180 nmol/1 and T.S.H.<0.1 mu/l). Clinical findings were of little use in making a diagnosis of hypothyroidism in this group of patients. A raised level of thyroid microsomal auto-antibodies was found in about a third of the patients, this occurred more commonly in females and slightly more often in those with a raised thyroid stimulating hormone. The importance of this is discussed. Recommendations for regular biochemical screening are made.