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Biomedical subjects

J Hungerford

Publications and source records attributed to J Hungerford.

43 records · Page 3Linked to original sources
PubMed1986

Effect of the esterase-D phenotype on its in vitro enzyme activity.

Esterase-D phenotypes and in vitro activity have been measured in red blood cells from 258 retinoblastoma patients and 73 unaffected relatives. Individuals with the 1-1 and 2-1 phenotypes showed distributions of enzyme activity which were not significantly different from each other. Individuals with the 2-2 phenotype, however, consistently showed a 25-30% lower level of enzyme activity. These results demonstrate the importance of determining the esterase-D phenotype in individuals with low ESD activity who might otherwise be assumed to carry a chromosome deletion at the esterase-D locus. We have also shown that, in vitro, the ESD enzyme is unstable over relatively short periods of time which, if uncontrolled, can give rise to a large variation in measured enzyme levels. The addition of b-mercaptoethanol to the assay buffer, which stabilises the enzyme, results in more consistent values being obtained within the same ESD phenotype. This feature could account in part for much of the variability in enzyme activity observed between different individuals in other studies.

Alleles↗
PubMed1986

Deletions of the esterase D locus from a survey of 200 retinoblastoma patients.

Esterase D levels from 200 retinoblastoma patients have been measured in an attempt to identify individuals carrying deletions of chromosome region 13q14. In this series 75% had bilateral tumours and 23% were familial. Of nine patients identified as having low esterase D levels, five had not previously been diagnosed as deletion carriers. These observations demonstrate the benefit of screening retinoblastoma populations for esterase D deficiency.

Adult↗
PubMed1986

Ocular sequelae of preterm birth and their relation to ultrasound evidence of cerebral damage.

The eyes of 177 very preterm (less than 33 weeks' gestation) infants, born between 1979 and 1982 and admitted to a neonatal intensive care unit, were examined as part of an ongoing follow-up study of neurodevelopmental outcome. Ocular pathology was diagnosed in 37 (21%) of the 177 infants: 14 (8%) had retinopathy of prematurity (ROP)--progressive in three--and nine (5%) infants had delayed visual maturation (DVM). The ocular pathology was permanent in 26 (15%) of the 177 infants. Refractive errors were the commonest problem and accounted for permanent sequelae in eight of the 14 infants with ROP and two of the nine with DVM. The presence or absence of ROP was related to a wide range of prospectively coded perinatal variables and to the results of routine neonatal ultrasound brain scans and neurodevelopmental follow-up assessments made in the first 18 months of life. As in previous studies, infants with ROP were of shorter gestation, lower birth weight, and required oxygen therapy for longer than unaffected infants, but the condition was only weakly associated with other indices of respiratory illness. In contrast, ROP was strongly associated with evidence of brain damage, often consistent with hypoxic ischaemic injury. We conclude that an underlying lesion in ROP may be hypoxic ischaemic damage to the retinal circulation.

Brain Diseases↗
PubMed1985

Current management of choroidal malignant melanoma.

Malignant melanoma is the most frequently encountered primary intraocular neoplasm. Within the eye this tumour arises in the uveal tract where the choroid is affected more often than the iris or ciliary body. The tumour occurs typically in middle life and the aetiology is not known. Uveal tissue is heavily pigmented in all races but ocular melanoma is notably rare in negroes. There is clinical and pathological evidence that malignant change may take place in a choroidal naevus, but melanoma has arisen in eyes documented to have no pre-existing pigmented lesion.

Brachytherapy↗
PubMed1984

Delayed visual maturation.

Sixteen blind babies who were considered to be showing the characteristics of delayed visual maturation were studied prospectively. The diagnosis was made on clinical grounds, and the criteria for this are discussed. All of these infants developed visual responses between 4 and 6 months of age and had normal or near normal visual acuities by 1 year of age. Long term follow up, however, has shown neurological abnormalities in some of these children.

Developmental Disabilities↗
PubMed1982

The influence of the size of the lens in ocular disease.

The mechanism of normal lens growth is considered. This involves both the surface accretion of new fibres and the central compaction of aging fibres. When lens growth is abnormal, it is shown to be retarded in most conditions, but accelerated in diabetes. The relationship between lens growth and ocular disease, in particular angle-closure glaucoma, is discussed.

Aging↗