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Biomedical subjects

C W Chow

Publications and source records attributed to C W Chow.

At least 127 records · Page 7Linked to original sources
PubMed1990

The clinical features of three babies with osteogenesis imperfecta resulting from the substitution of glycine by arginine in the pro alpha 1(I) chain of type I procollagen.

The features of three babies with lethal perinatal osteogenesis imperfecta resulting from the substitution of glycine by arginine in the pro alpha 1(I) chain of type I procollagen were studied. The babies were heterozygous for this substitution at residue 391 in case 1 (0I24), 667 in case 2 (0I51), and 976 in case 3 (0I30). They were all small, term babies who died soon after birth. The ribs were broad and continuously beaded in 0I24, discontinuously beaded in 0I51, and slender with few fractures in 0I30. The overall radiographical classifications were type IIA in 0I24, IIA/IIB in 0I51, and IIB in 0I30. Histological examination confirmed that the long bones were misshapen and porotic. The calcified cartilage trabeculae were covered with an abnormally thin layer of osteoid and the bone trabeculae were thin and basophilic. There was no evidence of lamellar bone or Haversian systems. The osteoblasts remained relatively large and closely spaced. These babies shared many phenotypic features, but differences in the radiographical appearance of the ribs and long bones suggested that there was a gradient of bone modelling capacity from the slender and overmodelled bones in 0I30 to the absence of modelling in 0I24.

Female↗
PubMed1990

Implantation metastasis of pineoblastoma after stereotactic biopsy. Case report.

A case is reported of implantation metastasis occurring 2 months after stereotactic biopsy of a pineoblastoma was performed in an 18-month-old child. Although implantation metastasis is well recognized after needle biopsy of solid tumors, it has not been described following stereotactic biopsy of a brain tumor. Implications for the role of stereotactic biopsy in the management of brain tumors is discussed.

Biopsy, Needle↗
PubMed1989

Striatal degeneration in glutaric acidaemia type II.

A girl of first cousin parents presented in the 1st year of life with a progressive neurological disease with muscle weakness and hypotonia, accompanied later by dystonia. Investigations, including gas chromatography of urine, showed no abnormality. Autopsy showed marked neuronal loss and gliosis in the putamen and globus pallidus. The activity of glutaryl-CoA dehydrogenase in cultured fibroblasts was normal, but the activity of electron transfer flavoprotein was markedly diminished. Retrospective study of urine by capillary gas chromatography/mass spectrometry showed small amounts of glutaric and other organic acids. This is the first report of striatal degeneration in association with glutaric acidaemia type II. The neuropathological changes were milder than those in glutaric acidaemia type I.

Child, Preschool↗
PubMed1989

Glomerulocystic renal disease: ultrasound appearances.

Renal and hepatic sonography were performed in 2 neonates with glomerulocystic renal disease. One neonate had ultrasound findings of normal hypoechoic medullary pyramids, enabling differentiation from infantile polycystic renal disease. Previous case reports have highlighted the similarity of renal ultrasound findings in these two conditions.

Humans↗
PubMed1989

Absence of the leaflets of the aortic valve in DiGeorge syndrome.

A newborn infant is described with complete absence of the leaflets of the aortic valve, interruption of the aortic arch and DiGeorge syndrome. This association has not previously been reported, nor has absence of the leaflets of the aortic valve without other features of left ventricular dysplasia. We discuss the possible influence of severe intra-uterine aortic regurgitation on development of the aortic arch.

Aortic Valve↗
PubMed1988

Neuropathology in glutaric acidaemia type 1.

The neuropathology in three cases of glutaric acidaemia type 1 is presented. All three showed extensive neuronal loss in the caudate nucleus and the putamen, with only small numbers of large neurons surviving. The globus pallidus showed moderate shrinkage and gliosis but no conspicuous decreases in neurons. Severe spongiform change was seen in many regions, involving predominantly white matter. These features are very similar to some cases described previously in familial striatal degeneration in childhood, but are different from other cases. If found in a brain at autopsy, they should lead to studies to diagnose glutaric acidaemia type 1 retrospectively, so that accurate genetic counselling and prenatal diagnosis in future pregnancies can be offered.

Child↗
PubMed1988

Rhizomelic chondrodysplasia punctata: clinical, pathologic, and biochemical findings in two patients.

The clinical, pathologic, and biochemical features of rhizomelic chondrodysplasia punctata are described in two patients. Although both patients had clinical and radiologic similarities, one patient survived for only 13 days and the other is still alive at 8 years. The most prominent pathologic feature was the marked degenerative change in the chondrocytes from resting cartilage. Fibroblast alkyldihydroxyacetone phosphate synthase activity was markedly reduced in both patients (approximately 10% of control mean); in contrast, dihydroxyacetone phosphate acyltransferase activity was only moderately reduced (50% of control mean). Alkyl and alk-l-enyl ether (plasmalogens) levels were very low in brain and liver. The accumulation of phytanic acid observed in plasma or liver was paralleled by a reduced ability of the patients' fibroblasts to oxidize phytanic acid. Our data indicate that the genetic defect in rhizomelic chondrodysplasia punctata results in abnormalities in two apparently unrelated pathways (i.e., phytanic acid oxidation and ether lipid biosynthesis.

Brain↗
PubMed1988

Cerebral infection with Escherichia coli O157:H7 in humans and gnotobiotic piglets.

Escherichia coli O157:H7 was isolated from a fatal case of haemorrhagic colitis with haemolytic uraemic syndrome and neurological symptoms. This strain induced diarrhoea and neurological symptoms including incoordination, ataxia, and convulsions in piglets after oral inoculation. Similar neurological signs were seen in piglets inoculated intraperitoneally with bacterial extracts containing a shiga-like toxin that is elaborated by the bacteria. Histological examination of the brains from these piglets showed vascular damage and small infarcts confined to the cerebellum. Comparable lesions were also seen in the brain of the child from whom E coli O157:H7 was isolated. We suggest that the cerebral changes in the piglets and in the patient were caused by the shiga-like toxin elaborated by E coli O157:H7. The shiga-like toxin is thought to cause neurological abnormalities by damage to cerebral blood vessels rather than by a direct effect on the neurones.

Animals↗
PubMed1988

Subependymal giant-cell astrocytoma in children. An unusual discrepancy between histological and clinical features.

The authors describe five cases of subependymal giant-cell astrocytoma in children in which many clinical, histological, immunohistochemical, and ultrastructural features typical of this tumor were present. However, prominent focal necrosis and mitoses, features usually associated with high-grade tumors, were seen in all cases. Despite the presence of necrosis and mitoses, clinical follow-up studies have revealed a lack of aggressive tumor behavior after surgery alone. The discrepancy between the histological and clinical features in these cases is emphasized so that excessive treatment of a basically low-grade tumor may be avoided. Mast cells were seen in all five cases, often in large numbers.

Cerebral Ventricle Neoplasms↗
PubMed1987

Identification of serotonergic neurons in human brain by a monoclonal antibody binding to all three aromatic amino acid hydroxylases.

A monoclonal antibody, PH8, has been isolated and shown by immunocytochemistry to bind to serotonergic and catecholaminergic neurons in sections of the rat and human brain. In human brain, obtained at autopsy, particular fixation and embedding conditions eliminate the labelling of catecholaminergic neurons while leaving intact the labelling of serotonergic neurons. This property makes the antibody of potential use for structural studies of serotonergic neurons in the normal and diseased human brain. PH8 was raised to pure monkey phenylalanine hydroxylase and has been shown to bind to the 50,000 mol. wt. phenylalanine hydroxylase polypeptide. Immunocytochemical and immunochemical evidence is presented in support of the hypothesis that the labelling of serotonergic and catecholaminergic neurons results from the binding of PH8 to tryptophan and tyrosine hydroxylase, respectively.

Adrenal Medulla↗
PubMed1987

Endocardial fibroelastosis in mucopolysaccharidosis type VI.

This case report describes two siblings less than 1 year of age who presented severely ill with a dilated cardiomyopathy. Full blood examination in both cases revealed marked granularity of neutrophils suggestive of mucopolysaccharidosis type VI. There were no physical features of a mucopolysaccharidosis but biochemical evaluation confirmed mucopolysaccharidosis type VI in both children. Autopsy in one patient confirmed endocardial fibroelastosis and electron microscopy of fibroblasts in the myocardium showed distention with membrane-bound vacuoles, consistent with a mucopolysaccharidosis. These siblings developed endocardial fibroelastosis before other clinical manifestations of the mucopolysaccharidosis. Assessment for metabolic causes of a cardiomyopathy is important, as cardiac disease may be the initial manifestation of a metabolic disease.

Endocardial Fibroelastosis↗
PubMed1987

Neuropathology in cerebral lactic acidosis.

The neuropathology in two young infants with cerebral lactic acidosis is presented. Both cases showed microcephaly, ventricular dilatation, absent corpus callosum, absent or extremely hypoplastic pyramids, heterotopic inferior olives, focal neuroglial overgrowth into meninges, focal cystic change with gliosis and recent degenerative changes in the germinal matrix. The cerebellum, basal ganglia, Ammon's horn, inferior colliculi and layering of the cortex were well preserved. The features suggest a continuous damage with very old, relatively old and recent lesions. This striking combination of abnormalities should raise the possibility of a disturbance of lactate/pyruvate metabolism.

Acidosis, Lactic↗
PubMed1987

Perivascular pseudorosettes in childhood brain tumours: an ultrastructural and immunohistochemical study.

Perivascular pseudorosettes (PP) in childhood central nervous system tumours were examined with light and electron microscopy and immunohistochemistry for glial fibrillary acidic protein, S-100 protein and albumin. One kind of PP at light microscopy comprised a central thin-walled vessel surrounded by a thick mantle of eosinophilic fibrillary material and rings of usually regular nuclei. Adjacent tumour tissue was compact. This type was correlated closely with ultrastructural evidence of ependymal differentiation. The central vessel showed continuous endothelium in all. Another type of PP comprised a central vessel of varying thickness surrounded by hyaline material, clearly defined tapering processes, and rings of often irregular nuclei. Adjacent tissue showed extensive edema and microcystic change. Ultrastructurally, this type showed no ependymal differentiation except in one myxopapillary ependymoma. Fenestrated vessels were seen in half of the tumours associated with this kind of PP. It is proposed that variation in vascular permeability, rather than in the structure of tumour cells, is the main cause for the difference in histological appearance of the two types of PP. Fenestrated vessels may also be responsible for the "myxoid" change in myxopapillary ependymomas. The amount of extracellular albumin showed no consistent correlation with the presence of fenestrations in vessels. A variable degree of positivity to GFAP and S-100 protein was seen in the tumours associated with both types of PPs with no clear difference in pattern.

Brain Neoplasms↗
PubMed1986

Alpha-feto-protein-(AFP-)-secreting intra-pericardial teratoma--report of a case diagnosed on CT scanning.

A three-month-old boy presented with acute tamponade and respiratory distress. Only CT scanning of the thorax suggested the presence of an intra-pericardial tumour compressing the heart and causing congestive cardiac failure. A large bilobed pedunculated tumour arising from the root of the ascending aorta was surgically excised. Initial serum AFP level was elevated. Histology revealed the tumour to be a teratoma with foci of yolk sac carcinoma. Alpha-feto-protein was demonstrable by immuno-histochemical staining in the yolk sac carcinoma component. The child remains well one year after removal of the mass.

Female↗
PubMed1986

Hereditary multiple glomus tumours.

A 9 year old girl presenting with multiple glomus tumours is reported. Multiple glomus tumours are rare, often asymptomatic lesions, with a familial tendency and found in a more proximal location than their solitary counterparts. In our report four close relatives had similar lesions. Indications for surgical excision are discussed.

Child↗
PubMed1986

X linked hydrocephalus: a survey of a 20 year period in Victoria, Australia.

This study ascertained 164 males with non-communicating hydrocephalus in live or stillborn patients in Victoria. Australia in 1962 to 1982, after excluding those cases secondary to brain malformations other than aqueduct stenosis. Ascertainment was considered near complete, especially for the period since 1974, but details of the aqueduct pathology were inadequate in half the cases. A total of 91 families was seen to record detailed family information. The overall incidence of primary non-communicating hydrocephalus was estimated to be 0.6 +/- 0.2 per 1000 live and stillbirths, with three-fifths of the cases male. Twelve patients were classified as having definite X linked hydrocephalus and 13 others as probable cases of this condition. Deformities of the thumbs (generally adduction deformity) were present in nearly half of these cases. The pyramids were absent from sections of the medulla whenever these were available. Four of five survivors had signs suggesting pyramidal tract lesions, compared to four of 25 surviving non-X linked cases. The intellectual outcome was notably poorer in the X linked cases. Poor school performance was also described in five of 19 mothers of X linked cases but in only one of 64 mothers of the remaining cases. Familial recurrence in the whole group of patients was almost confined to the X linked families. The exceptions were two families in whom autosomal recessive inheritance is possible. It is important to remember X linked hydrocephalus in genetic counselling. Examination of the thumbs, search for clinical signs of pyramidal tract lesions, and anatomical examination of the pyramids in medullary sections are all important, along with careful questioning for a history of affected maternal relatives. The presence of any of these features is grounds for counseling on the basis of X linked inheritance. An empirical figure was derived to use when counseling about a male with non-communicating hydrocephalus in whom there is no adequate information about the thumbs or the pyramids: a 4% recurrence risk in male sibs and 2% in females.

Australia↗