PubMed Health⌕ Search

Biomedical subjects

J G Rogers

Publications and source records attributed to J G Rogers.

At least 19 recordsLinked to original sources
PubMed1992

X-linked pyruvate dehydrogenase E1 alpha subunit deficiency in heterozygous females: variable manifestation of the same mutation.

Three female patients are described with pyruvate dehydrogenase (PDH) deficiency as a result of mutation in the X-linked gene for the E1 alpha subunit of the complex. Two of these patients illustrate typical presentations of PDH E1 alpha deficiency, with severe neurological dysfunction, degenerative changes and developmental anomalies in the brain, together with variable lactic acidosis. The third patient extends the known spectrum of the condition to include mild to moderate mental retardation and seizures in an adult. All three patients have the same mutation in the PDH E1 alpha gene. This mutation, a C-to-T substitution in a CpG dinucleotide in amino acid codon 302 (designated R302C), results in the replacement of arginine by cysteine at this position. The mildly affected adult was the mother of one of the other patient, making this the first described instance of mother-to-daughter transmission of a mutation causing PDH E1 alpha deficiency. The genetic basis of the variable expression of X-linked PDH E1 alpha deficiency in heterozygous females is discussed.

Adolescent↗
PubMed1992

Full data utilization in PVI using the 3D radon transform.

An algorithm is described for three-dimensional (3D) image reconstruction in positron volume imaging (PVI) using the inversion of the 3D radon transform (RT) for a truncated cylindrical detector geometry. A discrete version of the 3D RT is formed in a 3D histogram from the event-line coordinates of the detected events. The histogram entries represent the plane integrals of the activity in the field of view. Conventional inversion of the x-ray transform (XT) excludes oblique events in non-iterative reconstruction methods. by employing a spatially varying angular acceptance of events into the histogrammed plane integrals of the 3D RT, it is possible to include most of the detected oblique events in the reconstruction of the image using the standard 3D RT inversion formula. the oblique events are added to the histogram with a partial weight compared to those in complete (XT) projections. This single-pass reconstruction image has better statistical noise properties than images formed by RT inversion from complete XT projections, but only for some detector geometries is it significantly better. Monte Carlo simulations were used to study the statistical noise in images reconstructed using the new algorithm. The inherent difference in the axial versus the transaxial statistical noise in images reconstructed from truncated detectors is noted and is found to increase by including oblique events with this new algorithm.

Algorithms↗
PubMed1991

Williams syndrome in one dizygotic twin.

Williams syndrome is a disorder of unknown etiology with a characteristic facial appearance, vascular disease and infantile hypercalcemia. Most cases are sporadic. We report the case of a dizygotic male twin with the Williams syndrome. This appears to be the first report of twins with only one affected. This suggests a mutational event as the cause of Williams syndrome.

Aortic Valve Stenosis↗
PubMed1990

Autosomal recessive hydrocephalus with third ventricle obstruction.

Here we report a brother and sister who presented in the neonatal period with hydrocephalus. Ultrasonography showed marked dilatation of the lateral ventricles but not the third ventricle. One child with postnatal onset was shunted and had normal development at 3 years. The other child had severe hydrocephalus at birth and was not treated. Neuropathologic studies demonstrated dilatation of the lateral ventricles and marked narrowing of the posterior part of the third ventricle but no other malformations other than those that result directly from hydrocephalus. The potential for a good prognosis is emphasized.

Cerebral Ventricles↗
PubMed1990

Marfan syndrome: absence of type I or III collagen structural defects in 25 patients.

The structure and metabolism of type I and III collagens were studied in fibroblast cultures and dermis from 25 unrelated patients including 23 with typical Marfan syndrome and two infants with a very severe clinical form of this syndrome. Electrophoretic analysis of collagen alpha-chains, as well as one- and two-dimensional electrophoresis of collagen cyanogen bromide peptides, failed to show any evidence of primary structure defects or overmodification of lysine residues in these collagens. The proportion of hydroxylated prolyl residues in isolated alpha 1(I) chains was also normal. There was a minimal increase in the proportion of type III collagen produced by nine cultures. The findings in this study indicate that the underlying molecular defects in the patients studied are unlikely to involve the structure of the main fibrillar type I and III collagens.

Cells, Cultured↗
PubMed1990

Five cases demonstrating the distinctive behavioural features of chromosome deletion 17(p11.2 p11.2) (Smith-Magenis syndrome).

Children with hyperactivity and self-destructive behaviour present a difficult problem for parents and paediatricians. The syndrome described by Smith and Magenis is due to a deletion on the short arm of chromosome 17: del(17)(p11.2 p11.2). Clinical manifestations include brachycephaly and a flat mid-face; brachydactyly; short, broad hands; mental retardation; and aberrant behaviour, including hyperactivity. We report on five children, and review the literature on a newly recognised syndrome in which the behaviour manifestations may precede and often overshadow the learning disabilities and unusual appearance. In addition, we have found sleep disturbance to be a major feature in our patients.

Child↗
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

The clinical features of osteogenesis imperfecta resulting from a non-functional carboxy terminal pro alpha 1(I) propeptide of type I procollagen and a severe deficiency of normal type I collagen in tissues.

The features of a baby with lethal perinatal osteogenesis imperfecta (OI II), owing to a frameshift mutation that resulted in the production of a truncated and functionless carboxy terminal propeptide of the pro alpha 1(I) chain of type I procollagen, were studied. The baby (OI26) was heterozygous for an insertion of a single uridine nucleotide after base pair 4088 of the prepro alpha 1(I) mRNA of type I procollagen. Only normal type I collagen was incorporated into the extracellular matrix of bone and dermis resulting in a type I collagen content of about 20% of control tissues. The baby was born at 35 weeks' gestation and died shortly afterwards. He was small and had the radiographical features most like those of OI IIB. The skeleton was poorly ossified. The ribs were discontinuously beaded and the femora were broad with multiple healed fractures of the diaphyses and metaphyses. Other long bones had broad metaphyses with overmodelled diaphyses. The calvarium contained many hundreds of wormian bones. Histological examination showed grossly deficient endochondral and intramembranous ossification. The bone was of a woven type without evidence of lamellar bone or Haversian systems and the osteoblasts did not mature into osteocytes. The cortex of the femur contained Haversian canals but they were surrounded by loose collagen fibres and a mosaic pattern of woven bone and islands of cartilage. We propose that OI IIB can be sub-classified into two groups, one with helical mutations and both normal and mutant type I collagen in the tissues, and the other with carboxy terminal propeptide mutations and a severe type I collagen deficiency, but without mutant collagen in the tissues.

Bone and Bones↗
PubMed1990

Development of the hip in multiple epiphyseal dysplasia. Natural history and susceptibility to premature osteoarthritis.

We have determined the natural history of hip development in 42 patients with multiple epiphyseal dysplasia (MED). Premature osteoarthritis was a frequent outcome and was almost inevitable before the age of 30 years in those with incongruent hips. There were two types of immature hips: type I, the more severe form, had a fragmented and flattened ossific nucleus and acetabular dysplasia, was misshapen at skeletal maturity and osteoarthritic by 30 years of age; the milder type II hip had a small, rounded, uniformly ossified nucleus and a more normal acetabulum. Type II hips were well formed at maturity and were less prone to premature osteoarthritis. Considerable variations were noted in the manifestations of MED between families but not within families. The prognosis of a child's hip could be predicted; in sporadic cases from the type of immature hip, and in familial cases by also taking into account the outcome of affected relatives.

Adult↗
PubMed1989

Myocardial fibrosis in endomyocardial biopsy specimens: do different bioptomes affect estimation?

Estimation of fibrosis in endomyocardial biopsy specimens (EMB) is integral to their assessment; typically, EMB fibrosis is assessed qualitatively. We quantitated percent fibrosis in 697 paraffin-embedded, Masson's trichrome stained EMB taken from 6 sites along the right ventricular septum and from 1 site in the left ventricular free wall, utilizing Caves-Schultz (C-S) and Cordis (C) bioptomes and a scalpel in 34 formaldehyde-fixed autopsy hearts, 22 of which were anatomically normal (AN) and 7 of which were idiopathically dilated. Total tissue area and area of fibrosis were quantitated by computer-based image analysis. The mean total areas as obtained by the C-S and C bioptomes and scalpel were 0.0535 cm2 (+/- 0.028), 0.0338 cm2 (+/- 0.020), and 0.4370 cm2 (+/- 0.144), respectively. The C-S and C bioptomes and the scalpel from all hearts yielded percent fibrosis of 10.6, 12.3, and 5.4, respectively. The AN hearts had percents of 9.3, 11.8, and 4.5, while the ID hearts had 11.0, 13.7, and 7.3% fibrosis, respectively, by each sampling method. A consistent pattern was observed: the larger the piece of endomyocardium, i.e., scalpel greater than CS greater than C, the lesser the quantitated percent fibrosis. Thus, beyond allowing for biological variability in the degree of endomyocardial fibrosis, the impact of EMB size and the biotome type must be accommodated in qualitative surgical reports pertaining to myopathic hearts.

Adult↗
PubMed1988

"Cerebral" lactic acidosis: defects in pyruvate metabolism with profound brain damage and minimal systemic acidosis.

Six patients are described with a combination of early onset of neurological symptoms, gross cerebral changes and elevated concentrations of pyruvate and lactate in cerebrospinal fluid. Although at least five of the six patients appear to have a generalised defect in pyruvate metabolism, reflected in deficient pyruvate dehydrogenase activity in cultured fibroblasts, systemic acidosis was not a problem clinically and blood pyruvate and lactate concentrations were only slightly raised. The localisation of significant clinical and biochemical problems to the central nervous system, coupled with the difficulties in making the diagnosis if analysis of cerebrospinal fluid (CSF) is not performed, lead us to term this condition "cerebral" lactic acidosis.

Acidosis, Lactic↗
PubMed1988

Absence of a lateral rectus muscle associated with duplication of the chromosome segment 7q32----q34.

Absence of the right lateral rectus muscle and hypoplasia of the left was found in a child with congenital esotropia. He had mental and physical retardation, bilateral optic nerve hypoplasia, and many minor dysmorphic features, including brachycephaly, high forehead, poorly folded, low set ears, epicanthic folds, exaggerated Cupid's bow, long philtrum, and single palmar creases. Unusual features were a markedly ridged palate and a plantar crease which passed from the first and second interspace across the lateral border of the foot. He was found to have an unbalanced karyotype with duplication of chromosome segment 7q32----q34 (46,XY,der(2),inv?ins(2;7) (q21;q32q34)mat). The mother, maternal aunt, and sister of the proband all had a balanced rearrangement and were phenotypically normal.

Abnormalities, Multiple↗
PubMed1987

Mild Sanfilippo syndrome: a further cause of hyperactivity and behavioural disturbance.

Sanfilippo syndrome (mucopolysaccharidosis type III) usually presents with severe behavioural disturbance and it has characteristic features. The patient's condition follows a neurodegenerative course; death generally occurs in the second decade. Five patients, from three families, who presented with a mild variety of the syndrome are reported here. Four of the five patients did not show the usual somatic features, and none showed regression. It is important that clinicians be aware of this mild variant so that appropriate tests can be undertaken in retarded children and adults.

Adult↗
PubMed1987

Lethal perinatal osteogenesis imperfecta due to the substitution of arginine for glycine at residue 391 of the alpha 1(I) chain of type I collagen.

A baby with the lethal perinatal form of osteogenesis imperfecta was shown to have a structural defect in the alpha 1(I) chain of type I procollagen. Normal and mutant alpha 1(I) CB8 cyanogen bromide peptides, from the helical part of the alpha 1(I) chains, were purified from bone. Amino acid sequencing of tryptic peptides derived from the mutant alpha 1(I) CB8 peptide showed that the glycine residue at position 391 of the alpha 1(I) chain had been replaced by an arginine residue. This substitution accounted for the more basic charged form of this peptide that was observed on two-dimensional electrophoresis of the collagen peptides obtained from the tissues. The substitution was associated with increased enzymatic hydroxylation of lysine residues in the alpha 1(I) CB8 and the adjoining CB3 peptides but not in the carboxyl-terminal CB6 and CB7 peptides. This finding suggested that the sequence abnormality had interfered with the propagation of the triple helix across the mutant region. The abnormal collagen was not incorporated into the more insoluble fraction of bone collagen. The baby appeared to be heterozygous for the sequence abnormality and as the parents did not show any evidence of the defect it is likely that the baby had a new mutation of one allele of the pro-alpha 1(I) gene. The amino acid substitution could result from a single nucleotide mutation in the codon GGC (glycine) to produce the codon CGC (arginine).

Amino Acid Sequence↗