Search PubMed⌕ Search

Biomedical subjects

J Gibson

Publications and source records attributed to J Gibson.

At least 217 records · Page 12Linked to original sources

The association of blood pressure levels and change in renal function in hypertensive and nonhypertensive subjects.

We compared the changes in serum creatinine levels over time after a mean follow-up of 9.8 years in essential hypertensive (EH, n = 56) and control (n = 59) male veteran subjects. All subjects had normal serum creatinine levels (62 to 124 mumol/L) and "normal" urinalysis results on entry into the study. Subjects with comorbid renal diagnoses and diabetes mellitus were eliminated from the analysis. Although not statistically significant, the rate of change in the serum creatinine concentration over time was greater in the EH cohort compared with the control cohort (1.08 +/- 4.8 vs 0.027 +/- 3.5 mumol/L per year). The difference was especially marked in black EH subjects vs black control subjects (1.60 +/- 6.2 mumol/L per year vs -0.21 +/- 3.3 mumol/L per year). When age, race, body mass index, and a diagnosis of EH were entered into a logistic regression analysis, EH subjects had a statistically significantly greater rate of decline in renal function than did control subjects (1.5 +/- 8.3 mumol/L per year). When mean time-averaged systolic blood pressure for each subject was also included in the logistic regression analysis, only systolic time-averaged blood pressure was statistically significant (0.063 +/- 0.029 mumol/L per year). We conclude that in the absence of clinically detected parenchymal renal disease, EH subjects have a greater rate of decline in renal function than do nonhypertensive subjects. Time-averaged blood pressure is predictive of the change in serum creatinine concentration not only in EH subjects but also in nonhypertensive subjects. Thus, preservation of renal function may require a blood pressure lower than the currently accepted normotensive range.

Blood Pressure↗

Immunophenotypic analyses of cultured hemopoietic mast cells.

Immunophenotypic analyses of immature stage (day 19-23), intermediate stage (day 28-32), mature stage (day 34-37), and older stage (day 42-44) human hemopoietic mast cells from colonies grown in semi-solid agar cultures were performed to study the ontogeny and identity of this cell type and its relationship to other leukocytes. Intermediate to mature stage mast cells were positive with the YB5.B8 mouse monoclonal antibody, (McAb) specific for human mast cells, whereas the reactivity of immature mast cells with this McAb was inconsistent and older cells were generally negative. Mast cells at all stages of maturation were strongly positive for IgE receptor sites and negative with the Bsp-1 McAb, specific for human basophils. Mast cells at all stages of maturation were also strongly positive with the monocyte McAbs RPA-M1 (CD11), positive with the monocyte McAb OKM5 and the monocyte/granulocyte McAbs BMA-210 and MY7 (CD13), strongly positive with the B-cell markers J5 (CD10) and anti-IgM, and positive with the plasma cell marker PCA-1 and to a lesser extent with the activated B-cell marker CD23. The mast cells were also strongly positive with anti-CD45 to the common leukocyte antigen and positive with an antibody to HLA-DR and an antibody to FVIIIC. They were negative for specific T-cell markers. The diversity of this phenotype supports the current concept that mast cells originate from the pluripotential progenitor cells in the bone marrow.

Antibodies, Monoclonal↗

The West of Scotland BDA Branch membership survey.

The Executive Committee of the West of Scotland Branch of the BDA decided to investigate the views of the members on the way that branch activities were being run. A sub-committee was set up to plan and carry out a survey and to report on the results.

Attitude of Health Personnel↗

Quantitative bacteriology of a case of acute parotitis.

It is generally assumed that the microorganisms responsible for acute suppurative parotitis are facultative anaerobes, primarily Staphylococcus aureus and Streptococcus viridans. A quantitative microbiologic investigation of an aspirate of pus from the case we report revealed a microbial flora (5.1 X 10(6) CFU/ml) consisting entirely of strict anaerobes (Fusobacterium nucleatum and Peptostreptococcus anaerobius). The strain of F. nucleatum was sensitive to metronidazole but resistant to penicillin, amoxicillin, and erythromycin (minimum inhibitory concentration greater than 16 micrograms/ml). P. anaerobius was sensitive to the antibiotics tested. It is concluded that a high concentration of viable anaerobic bacteria may be present in acute suppurative parotitis and thus pus obtained from cases of sialadenitis should be cultured with microbiologic methods capable of isolating strict anaerobes. Additionally, antibiotic sensitivity should be determined routinely.

Acute Disease↗

The use of an amino-acid-based CAPD fluid over 12 weeks.

Eight patients with end-stage renal failure (plasma albumin less than 35 g/l) who were established on glucose CAPD exchanges, were studied for 4-week periods before, and after 12 weeks when 1% amino-acid solution had been used for the morning exchange. Anthropometric, biochemical, clinical and dietary assessments were made every 4 weeks. Dietary intakes of protein and calories were maintained. Studies with amino-acid solutions showed a mean of 13% and 8% amino acids remaining in the dialysate after 6 and 8 h respectively. Plasma amino acids increased to a maximum after 2 h of dialysis; however, fasting concentrations were constant over the 5 months. Osmolality of amino acids decreased comparably with 1.36% glucose during 8-h exchanges although the recovery of fluid was marginally less. Plasma transferrin increased significantly after 8 weeks of amino acids but subsequently decreased in one patient due to infection. No significant changes occurred in albumin, apolipoprotein A, IgG, IgA or prealbumin. Cholesterol and apolipoprotein B decreased in seven patients but increased in one due to rising calorie intake. Increases in urea and decreases in bicarbonate were not clinically significant. Amino-acid-based fluid was well tolerated with modest nutritional benefit and reduction in hyperlipidaemia. Optimal effects of amino acids are likely at higher concentrations using two or more exchanges in patients eating less than 0.9 g protein/kg per day.

Absorption↗

Human cardiolipin as the antigen in an ELISA to detect anticardiolipin antibodies.

Human cardiolipin was purified from cadaver heart tissue and used as the antigen in an enzyme-linked immunoassay (ELISA) for anticardiolipin antibodies. The correlation between assays using human and bovine cardiolipin was r = 0.90. Of the lupus anticoagulant positive patients 88% had antibodies to the human antigen and 75% had antibodies to the bovine antigen. Six of 45 samples contained antibodies which only reacted with the human antigen. All six samples remained positive when retested with a different human cardiolipin preparation and were negative when tested against a preparation of sheep cardiolipin. These studies suggest that there was increased specificity when human cardiolipin was used as the phospholipid antigen.

Animals↗

Very high dose intravenous gammaglobulin in thrombocytopenia of pregnancy.

A 22-year-old woman with severe idiopathic thrombocytopenic purpura, complicating pregnancy, was unresponsive to high-dose corticosteroids and three separate infusions of high-dose intravenous immunoglobulin using the conventional schedule of 400 mg/kg/d for five days. A dramatic albeit transient, elevation of her platelet count followed a six day course of very high dose immunoglobulin (1000 mg/kg/d) thus allowing elective lower segment cesarean section to be performed without complications and with the delivery of a live, female infant. Two months later a further course of very high dose gammaglobulin was again effective in raising the patient's platelet count prior to elective splenectomy. No adverse reactions were seen to either infusion.

Adult↗

Immune hemolysis after an ABO mismatched renal transplant.

We describe a case of immune hemolysis due to anti-B occurring in a blood group B patient 16 days after a cadaveric renal transplantation from a blood group O donor. Transfusional support was initially required and the direct antiglobulin test (DAT) remained positive for 80 days. Cyclosporin A (CSA), which was used for rejection prophylaxis in this case, has unique immunosuppressive capabilities which protects transplanted organs from rejection, but which might permit this type of 'graft versus host' reaction.

ABO Blood-Group System↗

A randomised trial of empirical antibiotic therapy in febrile neutropenic patients with hematological disorders: ceftazidime versus azlocillin plus amikacin.

One hundred and two patients with neutropenia (less than 1 x 10(9)/L) secondary to primary hematological disorders or chemotherapy for hematological malignancies were prospectively randomised, upon the development of fever or other signs of infection, to receive empirical antibiotic treatment with either ceftazidime (+/- flucloxacillin) (n = 52) or azlocillin plus amikacin (+/- flucloxacillin) (A&A, n = 50). The two groups were equivalent with respect to clinical and laboratory parameters prior to antibiotic therapy and flucloxacillin was added to approximately 25% of the patients in each group on the clinical suspicion of Gram positive infection. When assessed at 96 hours, the complete response rates were 59.6% for the ceftazidime treated patients and 44% for A&A treated patients. Partial response rates were 17% and 20% respectively. This difference was not statistically significant. Eight patients died whilst on the trial, three of those initially randomised to ceftazidime and five initially randomised to A&A. Moderate to severe hypokalemia was encountered significantly less often in the ceftazidime treated group (p less than 0.01), whilst other parameters of toxicity were equivalent. No primary or acquired resistance to ceftazidime was encountered. Separate analysis of those patients who did not receive flucloxacillin yielded identical results. We conclude that ceftazidime (+/- flucloxacillin) is as efficacious as azlocillin plus amikacin (+/- flucloxacillin) in the empirical antibiotic management of such patients and is associated with a lower incidence of moderate to severe hypokalemia.

Adolescent↗

Gallium scanning in the management of mediastinal Hodgkin's disease.

Gallium-67 scanning was performed pre- and post-therapy in 25 patients with Hodgkin's disease and a mediastinal mass. At restaging after therapy, radiographs (or CT scans) did not predict the presence of active disease whereas gallium scans did with a high degree of accuracy. Gallium-67 determined disease activity in those patients who had a residual mediastinal mass predicting outcome in 11 out of 12 patients; one had a late relapse at 7 years. In patients without a residual mass gallium scanning was again accurate, predicting outcome in 11 of 13 patients. Two patients with negative gallium scans but subsequent active disease were scanned too soon after chemotherapy. The results suggest that gallium scanning has an important role in the management of mediastinal Hodgkin's disease and is superior to all current methods of assessing disease activity irrespective of the presence of a residual mediastinal mass.

Adolescent↗

Involvement of coenzyme A thioesters in anaerobic metabolism of 4-hydroxybenzoate by Rhodopseudomonas palustris.

The initial steps of anaerobic 4-hydroxybenzoate degradation were studied in whole cells and cell extracts of the photosynthetic bacterium Rhodopseudomonas palustris. Illuminated suspensions of cells that had been grown anaerobically on 4-hydroxybenzoate and were assayed under anaerobic conditions took up [U-14C]4-hydroxybenzoate at a rate of 0.6 nmol min-1 mg of protein-1. Uptake occurred with high affinity (apparent Km = 0.3 microM), was energy dependent, and was insensitive to external pH in the range of 6.5 to 8.2 Very little free 4-hydroxybenzoate was found associated with cells, but a range of intracellular products was formed after 20-s incubations of whole cells with labeled substrate. When anaerobic pulse-chase experiments were carried out with cells incubated on ice or in darkness, 4-hydroxybenzoyl coenzyme A (4-hydroxybenzoyl-CoA) was formed early and disappeared immediately after addition of excess unlabeled substrate, as would be expected of an early intermediate in 4-hydroxybenzoate metabolism. A 4-hydroxybenzoate-CoA ligase activity with an average specific activity of 0.7 nmol min-1 mg of protein-1 was measured in the soluble protein fraction of cells grown anaerobically on 4-hydroxybenzoate. 4-Hydroxybenzoyl-CoA was the sole product formed from labeled 4-hydroxybenzoate in the ligase reaction mixture. 4-Hydroxybenzoate uptake and ligase activities were present in cells grown anaerobically with benzoate, 4-hydroxybenzoate, and 4-aminobenzoate and were not detected in succinate-grown cells. These results indicate that the high-affinity uptake of 4-hydroxybenzoate by R. palustris is due to rapid conversion of the free acid to its CoA derivative by a CoA ligase and that this is also the initial step of anaerobic 4-hydroxybenzoate degradation.

Acyl Coenzyme A↗

Multiple myeloma: evidence that light chains play an immunoregulatory role in B-cell regulation.

Supernatants from human lymphoblastoid and plasma cell lines were added to cultures of normal cells stimulated with pokeweed mitogen (PWM) with the aim of providing an in vitro model for light chain isotype suppression (LCIS). Supernatants from the kappa-secreting cell line LICR-LON-HMY2 were specifically able to block the secretion of kappa-associated immunoglobulin and supernatants from the lambda-secreting cell line U266 were specifically able to block the secretion of lambda-associated immunoglobulin without any effect on the secretion of the other light chain isotype. Supernatant from a human leukemia line, HL60, did not block either kappa or lambda immunoglobulin secretion. Purging studies where kappa or lambda light chains were removed from supernatants of these cell lines suggest that this is a direct effect of light chain and not due to any other nonspecific inhibitory material which may be present.

B-Lymphocytes↗

Polyethylene glycol in the production of blood grouping reagents: some further advantages.

The use of various water-soluble non-ionic polymers, including polyethylene glycol (PEG) 8000, has been described in the preparation of diagnostic blood grouping reagents. The major advantages of using PEG in this way are ease of preparation and the ability to concentrate antibodies. We describe here two previously unreported advantages of using PEG: (i) substantial reductions in the volume of red cells required for adsorption of isoagglutinins; and (ii) the ability to store PEG precipitates in a 'dry' form substantially reduces storage requirements.

Blood Grouping and Crossmatching↗

Clinical response of hairy-cell leukaemia to interferon-alpha: results of an Australian study.

Twelve patients with documented, progressive hairy-cell leukaemia were treated with human lymphoblastoid interferon-alpha. All patients initially received a three-month course of interferon-alpha (3 x 10(6) U each day) which resulted in two complete remissions and 10 partial remissions. All eight patients who were dependent upon packed red-cell transfusions became independent of them and the three patients with the most severe, pretreatment pancytopenia also became independent of platelet transfusions. The histological appearance of the bone marrow improved in all patients; in three patients, a complete resolution of the leukaemic infiltrate was recorded. Adverse reactions occurred in 10 patients, but these were mild and did not interrupt treatment in seven patients. Moderate reactions that required a temporary reduction in the dose of interferon-alpha were seen in three patients. Ten patients subsequently received maintenance therapy with interferon-alpha (3 x 10(6) U, three times a week). A haematological improvement continued to be seen in all patients, and the results, with a minimum of one year of follow-up, are presented.

Adult↗