PubMed Health⌕ Search

Biomedical subjects

P Sharp

Publications and source records attributed to P Sharp.

At least 91 records · Page 5Linked to original sources
PubMed1985

Cerebro-hepato-renal (Zellweger) syndrome, adrenoleukodystrophy, and Refsum's disease: plasma changes and skin fibroblast phytanic acid oxidase.

Cerebro-hepato-renal (Zellweger) syndrome, adrenoleukodystrophy, and Refsum's disease patients can be divided into at least five distinct groups, according to the nature of their plasma changes and their fibroblast phytanic acid oxidase activities. The biochemical changes in the plasma vary from an increase in a single metabolite or group of structurally related metabolites, such as in X-linked adrenoleukodystrophy (ALD) and classical Refsum's disease, to an increase in a number of structurally distinct metabolites, as in neonatal ALD/Zellweger syndrome, and infantile Refsum's disease. All patients, with the exception of those with the X-linked form of adrenoleukodystrophy are deficient in phytanic acid oxidase activity. The great similarity observed in neonatal adrenoleukodystrophy/Zellweger syndrome and infantile Refsum's disease suggests that the basic biochemical lesion in each may be similar or at least closely related.

Adrenoleukodystrophy↗
PubMed1985

Splenectomy for massive splenomegaly.

The technique, and short and long term results, of splenectomy for massive splenomegaly are presented. The latter was defined as a spleen weighing in excess of 1.5 kg. Thirty-five of the 38 patients had a serious haematological disorder as the indication for the operation, usually non-Hodgkin's lymphoma or myelofibrosis. All operations were carried out through abdominal incisions. Accessible splenic attachments were divided, and the splenic artery was ligated in continuity, prior to posterior mobilization. Two patients (5.3%) died as a result of the operation, both deaths being due to sepsis. Septic and thrombo-embolic complications were common, and occurred both early and late after the operation. Overall, eight of the 12 deaths during the first postoperative year were due to the primary disease, whereas all of the five deaths after that time were due to causes other than the primary disease. Twenty-four patients lived at least 1 year, and 10 patients are alive for more than 5 years.

Hodgkin Disease↗
PubMed1984

Pharmacokinetics and hypotensive effect in healthy volunteers of pinacidil, a new potent vasodilator.

Preliminary investigation in 3 healthy volunteers suggested that intravenous pinacidil in a dose of 0.2 mg/kg had a potent but well-tolerated hypotensive action in the supine position. Facial flushing, uncomfortable chest sensation and distressing postural hypotension occurred at serum concentrations above 300 ng/ml. Pinacidil, 0.2 mg/kg, was given intravenously over 4 min to 15 healthy volunteers in the supine position. Maximum fall in mean arterial pressure (MAP) was 15.7 +/- 6.0 mmHg. Maximum rise in heart rate was 23.8 +/- 6.6 beats/min. Pinacidil serum distribution half-life (T1/2 alpha) was 13.4 +/- 8.5 min and elimination half-life (T1/2 beta) was 2.13 +/- 0.49 h. The apparent volume of distribution (Vd beta) was 90.3 +/- 13.21 and total body clearance was 31.1 +/- 9.61/h. Pinacidil was approximately 40% bound to plasma protein over the concentration range 40-400 ng/ml. Urinary excretion of unchanged pinacidil accounted for 5.7 +/- 1.3% of the administered dose over 24 hours and urinary excretion of the major metabolite, pinacidil pyridine-N-oxide, was 31.6 +/- 9.2% of the administered dose. It was concluded that intravenous pinacidil is a potent vasodilator hypotensive compound, with a duration of action between 1.5 and 2 h.

Adult↗
PubMed1984

Infantile Refsum's disease (phytanic acid storage disease): a variant of Zellweger's syndrome?

The activity of phytanic acid oxidase is low in infantile and adult Refsum's disease, and in the cerebro-hepato-renal (Zellweger's) syndrome. The plasma of patients with the infantile but not the adult form of Refsum's disease contains increased amounts of pipecolic acid and of at least two abnormal bile acids, one of which has been identified as 3 alpha, 7 alpha, 12 alpha trihydroxy-5 beta-cholestan-26-oic acid. These changes are similar to those reported in the Zellweger syndrome and indicate that there may be similarities in the metabolic defects in Zellweger's syndrome and the infantile form of Refsum's disease.

Abnormalities, Multiple↗
PubMed1984

Plasma and skin fibroblast C26 fatty acids in infantile Refsum's disease.

In infantile and adult Refsum's disease, the activity of phytanic acid oxidase is low in skin fibroblasts, but plasma phytanic acid levels are high. Cultured skin fibroblasts and plasma from patients with the infantile, but not the adult, disorder show marked increases in the concentration of the long-chain fatty acid, hexacosanoic acid (C26), a feature once thought pathognomonic of adrenoleukodystrophy or Zellweger's syndrome.

Adrenoleukodystrophy↗
PubMed1982

Sex chromosome pairing during male meiosis in marsupials.

The pairing of the sex chromosomes at pachytene has been examined in twenty-two species of Australian marsupials, including four with complex sex chromosome systems. The axial elements of the sex chromosomes associate in all but one species. However, no synaptonemal complex has been observed between the axes of the X and Y chromosome in any of the examined species. Both the type of association between the sex chromosome axes, and the structural modifications of these axes are conserved within taxonomic groupings. In three species with complex sex chromosome systems, the t(XA), Y, A trivalents do not have a favoured relative orientation of the axes of the Y and A chromosomes, whereas in a fourth species with a t(XA1), t(A2YA1), A2 system the t(XA1) and A2 axes are in a cis arrangement with each other.

Animals↗
PubMed1981

Hoechst 33258 induced uncondensed sites in marsupial chromosomes.

The fluorochrome Hoechst 33258 induces pronounced uncondensed regions at mitosis at one or more specific sites on the X chromosomes of all eighteen species of marsupials belonging to the family Macropodidae which have been examined. The Y chromosomes of nearly all of these species also show sensitive sites. Autosomal regions which respond to this chemical were observed in only five species and there is evidence of polymorphism for two of these. The regions which respond usually show C-banding, but not all C-banding regions are affected. No specific effect was found in the chromosomes of eleven other species examined which are representative of 5 different Australian marsupial families. The implications of the apparent restriction of sex chromosome sensitive sites to macropods are discussed.

Animals↗
PubMed1981

Verification of the structure of the complex sex chromosome system in Lagorchestes conspicillatus Gould (Marsupialia: Mammalia).

The complex sex chromosome system of Lagorchestes conspicillatus has been reinvestigated using G-banding, Hoechst 33258 sensitivity, and Ag staining. These investigations demonstrate that, as proposed, three exchanges have been involved in the evolution of this system. An autosome was translocated to the original X and the homologue of that autosome was translocated to the original Y. An additional autosome has been translocated to the Y. There is no sex vesicle at meiosis in the male, and no association between the original X and Y elements of the compound chromosomes. The inadequacies of the present terminology for complex sex chromosomes are considered and an alternative system suggested.

Animals↗
PubMed1981

The distribution of SCEs within and between the genomes of an interspecific hybrid.

The distribution of sister chromatid exchanges has been examined in the chromosomes of a hybrid male wallaby (Macropus rufogriseus female x Wallabia bicolor male), and in the X chromosomes of M. parryi and M. rufus. Comparisons were made of SCE frequency between the two genomes of the hybrid, only one of which has an appreciable amount of constitutive heterochromatin, and between he euchromatic and heterochromatic regions of the M. rufogriseus genome. The frequency of SCEs is closely correlated with the DNA content of the individual chromosomes. The distribution of the SCEs between the euchromatin and heterochromatin in the M. rufogriseus genome showed a deficiency of SCEs observed in the heterochromatin compared with the euchromatin. - A substantial excess of SCEs occurred at the nucleolar organiser region of the M. rufogriseus X chromosome. This excess was absent from the nucleolar organiser region of the X chromosome of the two other macropodine species studied and is accounted for by the presence of an adjacent euchromatin-heterochromatin junction.

Animals↗
PubMed1979

Evaluation of three serological tests for the diagnosis of hydatid disease.

A number of techniques is used for the serological diagnosis of hydatid disease; however previous investigations suggest variable degrees or reliability for each test. This study reports an evaluation of the sensitivity and specificity of three commonly used serological tests for hydatid disease; complement fixation (CF), haemagglutination (HA) and the fluorescent antibody (FA) techniques. The results of these serological tests are compared in a series of specimens from 116 hospital patients, 21 of whom were confirmed surgically as having hydatid disease. A similar high degree of sensitivity was found for each of the three serological tests examined. The CF and HA tests gave negative results in two patients with confirmed hydatid disease, and the result of the FA test was negative in only one patient. The HA test was the most specific with no false positive reactions, but only two false positive reactions occurred with the FA test. The CF test was the least specific as the reaction was positive in nine patients without hydatid disease. When the results of both FA and HA tests were considered together, all 21 cases of hydatid disease were detected and false positive reactions occurred in only two patients.

Complement Fixation Tests↗
PubMed1978

The influence of size and radiopharmaceutical concentration ratio on the detection of abnormalities in clinical radionuclide imaging.

The effect of the size of an abnormality on its detectability was measured. The cylindrical abnormalities studied, with diameters ranging from 3 mm to 4 cm, were superimposed on a uniform background. To avoid artefacts produced by the imaging devices, the images were simulated by computer. The method of constant stimulus was used to determine the detectability of the abnormalities. By using a Perspex phantom filled with 99Tcm, measurements were made of the concentration ratio between abnormality and background which permitted detection of the abnormality. This allowed evaluation of the effectiveness of 99Tcm pertechnetate in the detection of small abnormalities. Assuming a concentration ratio between abnormal and normal tissue of 22.5:1, then at a depth of 50 mm in the brain a cylindrical abnormality of about 8 mm diameter was the smallest detectable under the chosen scanning conditions.

Brain Diseases↗
PubMed1977

Haemoperfusion with R-004 Amberlite resin for treating acute poisoning.

Eleven patients who had taken overdoses of barbiturates, glutethimide, tricyclic antidepressants, and chloroquine were treated by resin haemoperfusion using an R-004 haemoperfusion cartridge containing XAD-4 resin. All but one patient showed rapid clinical recovery and the drugs were cleared rapidly from the plasma. There were few complications. Resin haemoperfusion is more effective than dialysis and other perfusion methods, especially in poisoning with tricyclic antidepressants. Although haemoperfusion is expensive, it greatly reduces the length of the patient's stay in an intensive care unit and hence is cost-effective.

Acute Disease↗