PubMed Health⌕ Search

Biomedical subjects

G Owen

Publications and source records attributed to G Owen.

At least 19 recordsLinked to original sources
PubMed1992

Familial pancreatic enzyme insufficiency.

A father and son with profound reduction of exocrine pancreatic activity and little visible pancreatic tissue on ultrasound or computed tomography are described. Both have some degree of liver disease, which is more marked in the son. The disorder, apparently familial, does not correspond to any reported previously.

Amylases↗
PubMed1992

Vitamin A absorption in cystic fibrosis: risk of hypervitaminosis A.

Vitamin A status was examined in nine adult cystic fibrosis patients and six adult control subjects, together with an assessment of their ability to absorb 10,000 IU of retinyl palmitate from a test meal, taken with appropriate pancreatic enzyme supplements. Median baseline values for plasma retinol and carotene, as well as median serum retinol binding protein concentrations, were significantly lower in cystic fibrosis patients than in control subjects. One cystic fibrosis patient had a raised fasting plasma retinyl ester concentration suggestive of chronic hypervitaminosis A, but no symptoms of toxicity. Measures of vitamin A absorption were also significantly lower in cystic fibrosis patients, although there was considerable overlap with control values. No correlation was observed between measures of baseline status and vitamin A absorption. Measurement of plasma retinyl esters may be an appropriate investigation in those patients considered to be at risk of chronic hypervitaminosis A.

Adolescent↗
PubMed1992

Severity of chest disease in cystic fibrosis patients in relation to their genotypes.

A detailed comparison of the severity of chest disease with mutational status was carried out by cross sectional study of 127 cystic fibrosis patients, aged 1 to 31 years, living in Wales. Lung disease was classified according to severity, depending on pulmonary function tests (carried out on 76 patients) and chest radiograph status; information was obtained also on age at diagnosis in relation to severity of chest disease and colonisation with Pseudomonas species. Genotypes were determined by analysis for the mutations delta F508, delta I507, G551D, R553X, G542X, R117H, R560T, 1717--IG > A, and 621 + 1G > T. CF patients homozygous positive and heterozygous for the delta F508 deletion showed a significant decline of lung function with age. Unlike other studies, we did not find patients homozygous positive for the delta F508 deletion to have poorer lung function compared with heterozygous patients. Patients with the genotype 621 + IG > T/delta F508 tended to have more severe chest disease than the delta F508 homozygous patients in the same age group. There was some evidence that four patients heterozygous for R117H have mild chest disease.

Adolescent↗
PubMed1992

Prognostic factors in juvenile chronic granulocytic leukaemia.

A retrospective analysis of the clinical and haematological characteristics of patients diagnosed as having juvenile chronic granulocytic leukaemia between 1971 and 1986 was carried out. Thirty-three children were identified who were between the ages of 18 weeks and 8.8 years at diagnosis. The disease was more frequent in boys than girls (23:10). The most common presenting symptoms were skin rash (58%) and bleeding manifestations (45%). All patients had some degree of splenomegaly and in 88% this was more than 3 centimetres below the costal margin. Hepatomegaly and lymphadenopathy were also frequent findings. Anaemia was common and leucocytosis an invariable finding with a white cell count above 50 x 10(9) 1-1 in 42%. Monocytosis was found in 78%. Haemoglobin F measurements were available in 31 children and above 10% in 22 (67%). No child had the Philadelphia chromosome or monosomy 7. Thirty children were treated with chemotherapy, with a variable degree of symptomatic improvement. Twenty-nine patients had died with a median survival time of 5 months. The commonest cause of death was complications of bone marrow failure and no child developed acute leukaemia. Presenting characteristics associated with a longer survival period were age less than 6 months (P = 0.02), female sex (P = 0.02), HbF less than 10% (P = 0.0004) and the absence of bleeding manifestations (P = 0.03). We conclude that the prognosis for children aged over 6 months, with a raised HbF level is very poor, and that, in the absence of possible bone marrow transplantation, consideration should be given to novel treatment approaches for these patients.

Antineoplastic Agents↗
PubMed1991

Neonatal screening for cystic fibrosis in Wales and the West Midlands: clinical assessment after five years of screening.

Screening of the newborn for cystic fibrosis by measurement of immunoreactive trypsin has been undertaken on alternate weeks in Wales and the West Midlands for five years since 1985 to evaluate the possible clinical benefits of early diagnosis. Patients detected by screening and those diagnosed by clinical symptoms alone were assessed annually for differences in clinical, anthropometric, and biochemical variables. Fifty eight infants not considered to be at risk of cystic fibrosis (they did not present with meconium ileus and do not have a sibling with cystic fibrosis) have been detected by screening and they have been compared with 44 children who were diagnosed clinically. This latter group includes nine children whose screening was negative but who were recognised subsequently to have cystic fibrosis. The mean age at diagnosis of the screened group was significantly lower than that of the group diagnosed clinically. Excluding admissions for diagnostic tests for cystic fibrosis, the screened group spent a significantly shorter time in hospital during the first year of life. The results of all other comparisons made between the screened group and those diagnosed clinically were similar up to the age of 4 years.

Body Height↗
PubMed1990

The temporal and spatial changes in cell proliferation within the irradiated crypts of the murine small intestine.

The detailed temporal and spatial changes in the labelling index in crypts of the small intestine of the mouse have been analysed after 8.0 Gy gamma-irradiation. The labelling index was determined for each cell position in the crypts at 34 different times between 3 and 192 h after irradiation. The changes between consecutive time points have been analysed to determine the details of the crypt shrinkage and crypt repopulation phenomena. The following points can be made: (1) There is a dramatic reduction in the overall labelling of the crypt which begins within 3 h and is at its minimum by 15 h postirradiation. Most of this shrinkage can be attributed to continued near-normal emigration of cells from the crypt to the villus while mitosis is reduced or absent, and a possibly premature maturation within the transit population. (2) The labelling index never falls below 34 per cent of control, i.e. many labelled cells persist and continue to replicate their DNA at all times postirradiation. (3) Repopulation begins in the lower regions of the crypt. The first changes are an increase in labelling at cell positions 3-8 that begins at 3 h and reaches a peak at 12 h. There is a second increase in proliferation at the crypt base that begins at about 15 h and reaches a peak at 22-32 h postirradiation. There is a third peak which begins at about 46 h and reaches a peak at 60-70 h. (4) There is a reduction in proliferation at the crypt base that begins at about 72 h postirradiation. (5) The mid and upper crypt population shrinks initially to reach a minimum at about 15 h, after which there is a steady increase to reach a peak at about 72 h. The labelling spreads into the crypt-villus boundary area beginning at about 32 h. There is a reduction of proliferative activity in the mid-crypt region that begins at about 72 h. (6) There is a dramatic overshoot in overall labelling index at 72 h, which involves mainly the upper crypt. This does not revert to normal levels within the 192 h time scale of the present experiments. There is a mild overshoot in labelling at the crypt base at 48-78 h with a return to normal levels thereafter.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1990

Hepatic fibrosis in juvenile chronic granulocytic leukemia: an unusual finding in three cases.

We present 3 cases of juvenile chronic granulocytic leukemia in which there are histological changes in the liver of both portal and bridging fibrosis, with fibrosis around central veins, the latter being confirmed by quantitative measurement. We stress the histological differences from cirrhosis, nodular regenerative hyperplasia, and veno-occlusive disease and describe the evidence which favors an etiology from the leukemic infiltration rather than chemotherapy.

Cell Movement↗
PubMed1989

Tympanic membrane perforation following the removal of ventilation tubes in the presence of persistent aural discharge.

This study considers the effect of the removal of a ventilation tube from the tympanic membrane of an ear which has been affected with persistent mucopurulent discharge for at least 3 months. The records of 332 patients were reviewed. Thirty-three patients with 34 ears satisfied the entry criteria. Tube removal cured 27 out of 34 ears (79%) of aural discharge within 1 month. The tympanic membrane healing rates were: at 1 month, 14 (41%); at 3 months, 23 (68%); at 6 months, 24 (71%); and at 1 year, 28 (82%). A table is presented comparing perforation rates from different ventilation tube studies.

Adolescent↗
PubMed1986

Morphology of physiologically identified bipolar cells in the retina of the tiger salamander, Ambystoma tigrinum.

Intracellular recordings of the light responses of bipolar cells were made in the isolated perfused retina of the larval tiger salamander by microelectrodes filled with a 1% solution of the enzyme horseradish peroxidase (HRP). Two classes of bipolar cell were identified in terms of their responses to luminous spots and annuli centered upon their receptive fields: on-center cells, which depolarized in response to a centered spot and hyperpolarized in response to a concentric annulus, and off-center cells, which responded with the opposite polarities. Physiologically identified cells were labelled with HRP by iontophoretic injection and prepared for light microscopy. Examples of each of the three classes of bipolar cell described in Cajal's study of the amphibian retina were found amongst the labelled cells. The only morphological feature found to correlate with the physiological classification was the stratum at which the axon of the cell arborized in the inner plexiform layer. The axons of on-center cells arborized in the more proximal sublamina b, while those of off-center cells arborized in the more distal sublamina a. This is consistent with earlier findings in the retinae of the cat and the carp.

Ambystoma↗