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J Pattison

Publications and source records attributed to J Pattison.

At least 37 records · Page 2Linked to original sources
PubMed1997

Extent of antioxidant protection of plasma LDL is not a predictor of the antiatherogenic effect of antioxidants.

Oxidation of LDL plays all important role in atherogenesis. The lag-time in the formation of conjugated dienes provides a sensitive measure of the resistance of plasma LDL to oxidation and is widely assumed to be an indicator of atherogenic risk. To test this assumption, we investigated whether different antioxidants yielding similar lag-times result in similar reduction of atherosclerosis. A 6-months intervention study was carried out in three groups of 10 LDL receptor-deficient rabbits each. Because previous studies indicated that antioxidants that reduce atherosclerosis resulted in very long lag-times, the first group was treated with an antioxidant combination containing 1,000 IU vitamin E, 0.05% probucol analogue (BM15.0639), and 0.025% probucol. The lag-times achieved throughout the intervention period by this combination (952 +/- 39 min) were matched in a second group (829 +/- 46 min) treated with a variable dose of probucol (0.0575-0.11%, average 0.091%). A third, untreated group served as a control. Plasma cholesterol levels of all groups were matched. Even though both treatments yielded similar antioxidant protection of plasma LDL, 0.091% probucol reduced aortic atherosclerosis by 51.7% compared to the untreated group (P < 0.005), whereas the antioxidant combination failed to reduce lesion formation. Thus, the lag-time is clearly not correlated with the antiatherogenic efficacy of different antioxidants. However, a weak correlation was found within the group treated with probucol only. Our results suggest that the degree of antioxidant protection of plasma LDL may not be a good indicator of the atherogenic risk, in general, and that probucol reduces atherogenesis by mechanisms not shared by all antioxidants.

Animals↗
PubMed1994

RANTES chemokine expression in cell-mediated transplant rejection of the kidney.

RANTES (regulated upon activation, normal T cell expressed and secreted) is a chemotactic cytokine (a chemokine) for memory T lymphocytes, monocytes, and eosinophils. RANTES expression was studied in renal allograft biopsy specimens. Although RANTES was not expressed in samples taken one hour after transplantation, or in native renal biopsy specimens from patients with cyclosporin nephrotoxicity, it was expressed during cell-mediated transplant rejection. RANTES mRNA was detected in infiltrating mononuclear cells and renal tubular epithelium, and RANTES protein was localised to mononuclear cells, tubular epithelium, and vascular endothelium. This suggests RANTES has a role in allograft rejection.

Biopsy↗
PubMed1993

The parallel Lack anaesthetic breathing system.

The parallel Lack system is a new modification of the Mapleson A system comprising separate inspiratory and expiratory tubes. To determine that the function of the system was that anticipated of a Mapleson A, the fresh gas flow requirements to prevent rebreathing during spontaneous ventilation were assessed in three situations: (1) a lung model (2) conscious volunteers and (3) anaesthetised patients. Two sets of criteria to define rebreathing were used; (A) those based on changes in ventilation or end-expired carbon dioxide tension and (B) minimum inspired carbon dioxide tension. Using A, rebreathing occurred at a fresh gas flow to minute ventilation ratio (VF/VE) of 0.75 for the lung model, and 0.73 for conscious volunteers. These results were comparable to those obtained for a Magill attachment. They were also close to the point at which mechanical dead space began to increase in the lung model. Criteria B gave much lower values for the onset of rebreathing. Rebreathing was present by criteria A in five of the six anaesthetised patients at a fresh gas flow of 60 ml.kg-1.min-1 (VF/VF of 0.78). The results confirm that the parallel Lack behaves as a Mapleson A system. The resistance to breathing posed by the parallel Lack was also comparable to the Magill system.

Adult↗
PubMed1993

The additional work of breathing imposed by Mapleson A systems.

The additional work attributable to breathing through five Mapleson A anaesthetic breathing systems (Magill, Lack, Parallel Lack, Humphrey ADE and Enclosed Magill) was studied using a lung model. With all five systems, the additional work was found to be a function of fresh gas flow, respiratory flow as well as system geometry. Within the range of fresh gas flow and respiratory flow studied, the additional work ranged between 80 mJ.l-1 and 182 mJ.l-1. Expiratory work was always greater than the inspiratory workload. Increasing fresh gas inflow into the system increases expiratory work, both resistive and elastic components. The Magill system posed the least work expenditure. The values for the additional work obtained with the lung model were of the same order of magnitude when measurements were taken in volunteers.

Adult↗
PubMed1993

Characterization of a nested polymerase chain reaction assay for detection of parvovirus B19.

The characterization and application of a nested polymerase chain reaction (PCR) assay for the detection of human parvovirus B19 DNA is described. The assay was evaluated with 149 diagnostic serum samples (collected up to 150 days after the onset of symptoms) previously tested by dot blot hybridization for B19 DNA and by class-specific capture radioimmunoassays for the detection of B19 immunoglobulin M (IgM) and IgG. B19 DNA was detectable by the PCR in 70% of the sera. There was a statistically significant association between the detection of B19 DNA by PCR and high B19 IgM values (P < 0.005), low B19 IgG values (P < 0.05), and a short interval between onset of symptoms and serum collection (P < 0.005). Serial serum samples, throat swabs, and peripheral blood mononuclear cells collected from 10 individuals during an outbreak of parvovirus B19 were also tested by the nested PCR. B19 DNA was detectable in the throat swabs at the time of the clinical illness and in the peripheral blood mononuclear cell fraction up to the end point of the study 6 months after infection. The location of the B19 DNA could not be determined in cytocentrifuge preparations of peripheral blood mononuclear cells with nonisotopic in situ hybridization and immunolabelling.

Antibodies, Viral↗
PubMed1992

Pre-oxygenation: the Hudson mask as an alternative technique.

The use of a simple oxygen facemask (Hudson) with high oxygen inflow (48 l.min-1) was investigated as a technique for pre-oxygenation, comparing it with the Magill system (oxygen flow: 100 ml.kg-1.min-1). One hundred and thirty-eight patients scheduled for elective gynaecological and orthopaedic surgery were studied: group 1, Hudson mask and group 2, Magill system (ASA 1-2, n = 107); group 3, Hudson mask and group 4, Magill system (ASA 3, n = 30). Pre-oxygenation was assessed by measuring the times to 97%, 95% and 93% arterial desaturation (finger pulse oximetry) following 3 min of pre-oxygenation. The times taken to achieve these end-points in all the study groups suggest that the Hudson mask offers an alternative technique for pre-oxygenation.

Adult↗
PubMed1991

The effects of intravenous clonidine on ventilation.

The effects of clonidine, an alpha 2 adrenergic agonist, on ventilation were studied in a group of adult volunteers. The ventilatory variables measured were minute ventilation, respiratory rate, end-tidal carbon dioxide tension and the response to carbon dioxide challenge. We found no differences in minute ventilation, respiratory rate and end-tidal carbon dioxide tension, before and after clonidine administration. However, the ventilatory response to carbon dioxide was significantly attenuated following clonidine, suggesting that clonidine has respiratory depressant effects.

Adult↗
PubMed1990

Caesarean section in a patient with haemoglobin SC disease and a phaeochromocytoma.

The anaesthetic management of a patient with haemoglobin SC disease for lower segment Caesarean section and excision of a phaeochromocytoma is described. The patient was given a general anaesthetic for the surgical procedure after exchange transfusion had achieved an haemoglobin A concentration of greater than 50%. A live infant was delivered and a suprarenal phaeochromocytoma was excised during a 6.5 hour procedure. The patient's postoperative recovery was uneventful.

Adrenal Gland Neoplasms↗
PubMed1988

Impaired neutrophil killing in a patient with defective degranulation of myeloperoxidase.

A case of recurrent, superficial abscesses in an 18 year old girl, is described. Staphylococcus aureus was the pathogen most often implicated and on several occasions the abscesses required surgical drainage. Defects in humoral immunity, neutrophil chemotaxis or opsonophagocytosis were not observed. However, her neutrophil's ability to kill ingested S. aureus in vitro was impaired. This was associated with impaired luminol-dependent chemiluminescence in response to stimulation by either latex beads, or the chemotactic peptide FMLP plus cytochalasin B. Oxygen uptake and superoxide anion production were normal but release of myeloperoxidase by this patient's neutrophils occurred more slowly and to a lower extent than in control cells. These data suggest that the recurrent infections and diminished in vitro neutrophil bactericidal activity observed in this patient are associated with impaired degranulation of myeloperoxidase.

Abscess↗
PubMed1981

Early and late reactions in contact sensitivity in the mouse.

Several phases of plasma extravasation have been identified during the course of a contact sensitivity challenge reaction in mice. An early reaction at 1 h is seen which may be mast cell mediated. This is followed by the main phase of extravasation at 3-4 h. This phase is not seen in mice sensitized for less than 5 days and is transferable passively by serum. Between 8 and 15 h there is a prolonged period of moderately intense extravasation which represents the delayed hypersensitivity component of the reaction. Beyond 15 h there is virtually no further extravasation.

Animals↗
PubMed1976

Enhanced antibody responses in active chronic hepatitis: relation to HLA-B8 and HLA-B12 and porto-systemic shunting.

Titres of antibodies to rubella, measles, smooth muscle, nuclei, and Escherichia coli were examined in relation to the presence of particular histocompatibility antigens in 57 patients with active chronic hepatitis, 8 of whom were HBsAg positive. With the exception of antibodies to E. Coli, the HBsAg-negative patients with HLA-B8 or HLA-B12 had higher titres than those with neither, and antibody titres were highest in the 7 cases with both these histocompatibility antigens. In contrast, E. coli antibody titres were not related to the presence of particular histocompatibility antigens but correlated closely with the degree of portosystemic shunting. None of the HBsAg-positive patients possessed HLA-B8, and titres of all the antibodies were significantly lower than in the HBsAg-negative cases. The increased antibody response in HBsAg-negative patients is likely to be due to a genetically determined increase in immunological responsiveness for which HLA-B8 and HLA-B12 are markers. The results obtained in healthy family members also suggest that this defect in immunoregulation is under polygenic control.

Antibodies↗