Biomedical subjects

D Burdon

Publications and source records attributed to D Burdon.

6 recordsLinked to original sources

PubMed2000

The role of tumor necrosis factor in the development of multiple organ failure in a murine model.

OBJECTIVE: To elucidate the role of tumor necrosis factor (TNF) in the development of multiple organ dysfunction syndrome (MODS) after zymosan-induced peritonitis in mice. DESIGN: Prospective controlled laboratory study on zymosan-induced generalized inflammation in mice. Over < or =28 days, a single intraperitoneal administration of zymosan induced a three-phase illness in C57BL mice, rendering them very ill with MODS-like symptoms from day 7 onward. Additionally, the same experiment was performed on C57BL/6 TNF-Rc-p55 knockout mice to elucidate the role of TNF and its receptor p55. SETTING: Animal research laboratory. SUBJECTS: Inbred C57BL mice and C57BL p55-/- mice received a single sterile intraperitoneal injection of zymosan suspended in paraffin oil (0.75 mg/g of body weight). MEASUREMENTS AND MAIN RESULTS: The animals were monitored for survival, condition, and body weight for < or =28 days. At 3, 7, 14, and 28 days after zymosan administration, bronchoalveolar lavage was performed and lungs and livers were extracted for isolation of RNA and histopathologic evaluation. Reverse-transcriptase-polymerase chain reaction was performed to quantify TNF-alpha messenger RNA (mRNA) in the respective organs. Both animal strains went through initial shock with a high mortality rate during the first 3 days. The C57BL mice developed MODS with typical symptoms and histopathologic results correlating with excessive TNF-alpha mRNA expression from day 7 onward. In contrast, no disease, histopathologic changes, nor TNF-alpha mRNA expression in liver or lung was found within the TNF-Rc-p55-/- mice. CONCLUSION: Organ-derived TNF-alpha plays a crucial role in the development of MODS in this murine model.

Animals↗

PubMed1998

Differences in the anti-inflammatory effects of theophylline and pentoxifylline: important for the development of asthma therapy?

Antiasthma drugs are now being re-evaluated for their anti-inflammatory effects. Theophylline is an immunomodulator; however, weak effects and the narrow therapeutic window make it a controversial drug. We compared the immunomodulatory potencies of theophylline with those of the xanthines pentoxifylline (POF) and A802715. Using a whole-blood, cell-culture system, we studied the effects on the release of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and interleukin-6 (IL-6) in six healthy subjects, and, in granulocyte suspensions, the effects on the release of reactive oxygen species (ROS). We also studied the influence of a 14-day treatment with theophylline or POF on the release of the cytokines named above in 14 asthmatics. We found that equimolar concentrations of A802715 most effectively inhibit ROS generation, followed by POF; the effects of theophylline were weakest. A802715-inhibited release of TNF-alpha was four times as potent as that of theophylline, and POF two times as potent. Inhibition of IFN-gamma by A802715 was three times as potent, and by POF two times. Neither drug influenced IL-6 release. After a 14-day treatment of asthmatics, POF proved to inhibit TNF-alpha release more effectively (by 44.3%) than theophylline (7.5%). It is concluded that study of xanthine derivatives in asthmatics might help the development of asthma therapy. POF seems to be an especially promising candidate.

Adult↗

PubMed1997

Anti-Borrelia burgdorferi immunoglobulin seroprevalence in pulmonary sarcoidosis: a negative report.

The aetiology of sarcoidosis is still unknown. An infectious microorganism as causal agent for this disease could not be identified, but high titres of antibodies against Borrelia burgdorferi were detected in Chinese studies implying a causality with this disease. These findings, however, could not be reproduced by other researchers. The aim of this study was, therefore, to evaluate the possible role of these spirochetes in the pathogenesis of sarcoidosis by serological examinations. Sixty sera of patients suffering from sarcoidosis were examined for anti-B. burgdorferi immunoglobulin by enzyme-linked immunosorbent assay (ELISA). ELISAs for these antibodies show a high sensitivity, but a low specificity; therefore, a specific immunoblot was used to confirm positive results. Initially, 8% of the patients were reactive in the ELISA, and 20% of these could be confirmed by immunoblot. Therefore, the prevalence for B. burgdorferi antibodies in sarcoidosis patients was 1.6%. This result did not differ significantly from the prevalence of B. burgdorferi antibodies in 1,000 regular blood donors of the city of Hamburg (7% reactive in the ELISA, 38% confirmed via immunoblot, prevalence 2.7%). The hypothesis of causality between a B. burgdorferi infection and sarcoidosis cannot be confirmed by this data.

Antibodies, Bacterial↗

PubMed1978

Diagnosis of pseudomembranous colitis.

Twenty-eight patients with histologically proved pseudomembranous colitis have been seen in one hospital since July 1975. All patients with the disease had received antibiotics, six for infections not requiring operations; the other 22 cases all occurred after major surgery. All the patients had diarrhoea; six patients also had fever with clinical signs of sepsis, and three had abdominal pain thought to be due to anastomotic dehiscence after colonic resection. Pseudomembranous colitis was associated with white blood counts over 15 000/mm3 in 17 patients and albumin concentrations of less than 30 g/1 in 18. Pseudomembranous colitis was an incidental finding at necropsy in two of six patients who had not had an operation. Of the 22 patients who had had major surgery, nine died from this complication; in all except two of these cases the diagnosis was made only at necropsy. If pseudomembranous colitis is suspected on clinical grounds or if there is an unexplained complication after colorectal surgery repeat sigmoidoscopy and testing for faecal toxins should be carried out to establish the diagnosis so that prompt supportive treatment can be given.

Adolescent↗

PubMedDate not supplied

The assessment of recovery in patients after myocardial infarction using three generic quality-of-life measures.

BACKGROUND: To evaluate the sensitivity to change of three generic quality-of-life measures in patients after myocardial infarction (MI). METHODS: Patients admitted to the Coronary Care Unit of Royal Devon and Exeter Healthcare Trust over a 9-month period were selected on the basis of a first MI and under 80 years of age. Quality of life was assessed 6 weeks and 6 months after MI using the Sickness Impact Profile (SIP), Nottingham Health Profile (NHP), and McMaster Health Inventory Questionnaire (MHIQ). An index of whether these measures are sensitive to change over time was determined by dividing the mean change from 6 weeks to 6 months of each instrument subscale by the baseline standard deviation of that subscale. Values of 0.2, 0.5, and 0.8 and above represent modest, moderate, and good sensitivity, respectively. RESULTS: Eighty-eight patients completed and returned the quality-of-life measures at both 6 weeks and 6 months. Four SIP subscales achieved a sensitivity to change index of 0.20 to 0.50: body care and movement, emotional behavior, work, and eating. Other SIP, NHP, and MHIQ subscales showed sensitivity index values of less than 0.20. No sensitivity index values of 0.50 or more were observed. CONCLUSIONS: During the period of this study, all three generic quality-of-life measures displayed only modest levels of sensitivity to change. Other quality-of-life measures need to be developed for the assessment of cardiac patients. This is particularly important when choosing suitable quality-of-life measures to assess cardiac rehabilitation.

Aged↗

PubMedDate not supplied

Clinical methods of goniometry: a comparative study.

This investigation compared the reliability and interchangeable use of three currently available goniometers--a universal goniometer, a fluid goniometer, and an electrogoniometer. Three consecutive readings of the active range of movement of the right elbow joint were taken from each of 23 healthy female volunteers; three experienced observers each used each type of goniometer on two occasions. A balanced experimental design was used to eliminate order effects with respect to subject, tester, or goniometer, and a rigid protocol was employed to reduce error due to diurnal or methodological variations. The results show that there are significant differences between the goniometers used, the testers, and the replications. Significant interaction effects also exist between the goniometers and the occasion, the goniometers and the testers, and the testers and replications. The data suggest that the interchangeable use of different types of goniometer in a clinical setting is inadvisable.

Adolescent↗