Search PubMed⌕ Search

Biomedical subjects

C Burns

Publications and source records attributed to C Burns.

At least 55 records · Page 3Linked to original sources
PubMed1994

Systemic and portal prostacyclin and thromboxane response to hemorrhage in portal hypertension.

Prostacyclin (PGI2) and thromboxane (Tx-A2) levels increase in hemorrhagic shock. Prostanoids have been implicated as mediators of the systemic and splanchnic hyperemia characteristic of portal hypertension (PHT). We hypothesized that prostanoid pharmacokinetics could be altered during shock in PHT and mediate the poor tolerance of PHT animals to hemorrhage. Hemodynamics and PGI2 and Tx-A2 levels were determined in portal, systemic venous, and arterial vascular beds at baseline and following hemorrhage and resuscitation. Portal and systemic PGI2 levels were elevated at baseline in PHT animals, with no change in resting Tx-A2. Following hemorrhage, PGI2 and Tx-A2 levels increased in normal animals, but were unchanged in PHT. Portal hypertension PGI2 production was elevated at rest, while Tx-A2 levels were diminished. There is a diminished prostanoid response to hemorrhage in PHT animals compared to normal. This abnormality in prostanoid pharmacokinetics may contribute to the abnormal response to hemorrhage in PHT.

Animals↗
PubMed1994

Intraoperative localization of parathyroid adenoma using 99Mtechnetium sestamibi.

We herein illustrate an unusual but very helpful maneuver in the localization of parathyroid adenomas that have proven difficult to find at initial surgical exploration. This case also illustrates how metabolically active thyroid tumors can interfere with the localization of parathyroid tumors when using the technetium-thallium subtraction scan technique, and a possible way of overcoming such interference.

Adenoma↗
PubMed1993

Effects of delayed processing on mammographic phantom object detection.

OBJECTIVES: Delayed processing of films is a common occurrence in mobile mammography screening programs. The effects of such delayed processing on radiologists' detection of phantom test objects are investigated. METHODS: Twelve screen-film combinations were exposed using a phantom and developed after delays of 0, 1, 2, 3, 5, and 7 days. Films were scored by three board-certified radiologists specializing in mammography, based on visibility of calcifications, masses, fibrils, and line pairs. RESULTS: Variance analyses of mean scores indicate that, across screen-film combinations, there are no statistically significant decreases in object detection associated with delayed processing. The analyses do indicate, however, a statistically significant difference in scores unrelated to delay, attributable to the screen-film combination used. CONCLUSIONS: Delayed processing of mammography film does not lead to a decrease in the visibility of phantom test objects, despite large decreases in overall image optical density.

Analysis of Variance↗
PubMed1993

Emergency nurses' perceptions of critical incidents and stress debriefing.

INTRODUCTION: This is a descriptive study of questionnaire responses of 682 members of three state ENAs, with supporting interview data from 26 of those participants. The objective was to determine (1) the types of clinical events perceived as critical and (2) the usefulness of critical incident stress debriefings for emergency nurses. METHODS: Questionnaires asking emergency nurses to rate clinical incidents as critical and to respond to questions about their experiences with debriefings were sent to members of three state ENAs. Structured interviews about personal experiences with critical incidents and debriefings were conducted with 26 respondents. RESULTS: Emergency nurses responding to the questionnaire viewed the death of a child and the death of a coworker as the most critical of the possible events. The majority of interviewees saw an incident related to the death of a child as the most critical in their careers. Of the questionnaire respondents, 32% had participated in debriefings; 88% of those found them helpful in reducing critical incident stress. DISCUSSION: The findings suggest that managers should be alerted to the possibility of acute stress responses when emergency nurses experience a child's death. Education regarding stress and debriefings may be helpful to ED personnel.

Adult↗
PubMed1992

Activation of human peripheral blood T lymphocytes by pharmacological induction of protein-tyrosine phosphorylation.

Protein-tyrosine kinase and protein-tyrosine phosphatase (PTPase) activities are essential for T-cell antigen receptor-mediated signaling. To assess the functional consequences of alteration of the levels of tyrosine phosphorylation in normal human T cells, the effects of vanadate and hydrogen peroxide were studied. In combination, these agents induced tyrosine phosphorylation of cellular substrates, elevated cytosolic free calcium, and induced interleukin 2 receptor (IL-2R) alpha chain expression but not IL-2 secretion. However, anti-CD28 antibody in combination with vanadate and hydrogen peroxide induced IL-2 secretion, consistent with the requirement for a costimulatory signal in the induction of this gene. The effects of vanadate and hydrogen peroxide were enhanced in the absence of the T-cell PTPase, CD45. Thus, acute pharmacologic manipulation of the level of tyrosine phosphorylation in normal T cells correlates with partial, but not full, activation of these cells; in concert with a costimulatory signal provided by perturbation of the CD28 molecule, the complete program of activation is initiated. These agents should prove useful in dissecting signaling pathways involved in the regulation of genes critical to the immune response.

Animals↗
PubMed1992

Pharmacological management of cancer pain. A guide for the health care professional.

Cancer pain continues to remain a significant problem for oncology patients treated in both the university and the community setting. Nursing knowledge regarding pain management has advanced significantly in recent years. This article provides health care professionals with current factual information on cancer pain management. The information focuses on the emotional aspects of cancer pain, specific principles of analgesic management, opioid equianalgesics, multiple approaches to opioid administration, management of unwanted side effects, and a description of inappropriate drug therapies.

Analgesia, Patient-Controlled↗
PubMed1991

Isolated significant left main coronary artery stenosis: angiographic, hemodynamic, and clinical findings in 16 patients.

Among 21,545 adult patients who underwent consecutive coronary angiography, 16 (0.07%) were found during their coronary arteriography to have a significant isolated stenotic lesion (luminal diameter narrowing of 50% or more) located at the left main coronary artery. The remaining major epicardial coronary arteries and their branches were free of disease. A strong predilection for the isolated lesion to occur at the ostium of the left main artery was found (12 patients). The most common presenting symptom was angina of less than 4 weeks' duration, although one third of the group was asymptomatic. Resting electrocardiograms were normal in 12 patients, while three patients had T wave inversion and another had nonspecific ST-T changes. Eleven patients exhibited severe stenosis, with eight having 70% to 89% stenosis and three having 90% to 95% stenosis. Five patients had 50% to 69% stenosis. No significant differences were found between patients with angina and patients without angina with respect to age, left ventricular end-diastolic pressure, left ventricular ejection fraction, and mean percent stenosis of the obstructive lesion. Despite the severity and the crucial location of the obstructive lesion, most patients with an isolated, significant left main stenosis appear to have a preserved left ventricular ejection fraction, normal wall motion, and no significant alteration of the left ventricular end-diastolic pressure.

Adult↗
PubMed1991

The contribution of medical nitrous oxide to the greenhouse effect.

Nitrous oxide is now recognised as an important contributor to the 'greenhouse' effect. Each year the medical profession unwittingly adds a very small burden of this gas to the atmosphere. Unfortunately, the long lifetime of nitrous oxide means that all emissions into the atmosphere are significant. By making small changes in their practices, anaesthetists are well-placed to help reduce the potential environmental damage.

Air Pollutants↗
PubMed1990

Low-dose oral administration of human interferon alpha can control the development of Theileria parva infection in cattle.

Two natural human interferon alpha preparations, (nHuIFN-alpha [Cantell]) and (nHuIFN-alpha [ISI]), were used for the oral treatment of cattle experimentally infected with Theileria parva parva. In the first experiment, 8 Friesian bulls were inoculated with a 1 in 10 dilution of a sporozoite stabilate of T.p. parva (Marikebuni) stock. Four of the cattle were treated daily with 1 international unit/kg body weight (i.u./kg bwt) of nHuIFN-alpha (Cantell) from day -2 to day 8 p.i. None of the 4 calves given IFN developed clinical theileriosis, but 3 of the 4 control calves died of theileriosis while the fourth had a mild infection. Three of 4 treated calves and the 1 surviving control calf developed a detectable antibody response to T.p. parva schizont antigen but, on challenged with a 10-fold higher dose of stabilate, the surviving control animal and only 1 of the 4 treated calves proved to be immune. In a second experiment, 4 groups of 4 calves were inoculated with the same stabilate dilution. Three treatment groups were given either 1 i.u. nHuIFN-alpha (Cantell), 1 i.u. nHuIFN-alpha (ISI), or 10 i.u. nHuIFN-alpha (ISI)/kg bwt from day -2 to day 8 p.i. once daily and the fourth group were controls. Clinical theileriosis occurred in 2 controls, 2 calves given 10 i.u. nHuINF-alpha (ISI), 1 calf given 1 i.u. nHuIFN-alpha (ISI) and no calves given 1 i.u. nHuIFN-alpha (Cantell)/kg bwt. Of these, 2, 1, 0 and 0 cattle died in the respective groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Effect of heat inactivation of HIV on specific serum proteins and tumour markers.

The effect on the concentrations of specific serum proteins and tumour markers, of heat-treating samples at 56 degrees C for 30 min to inactivate HIV, was investigated. Statistically significant decreases, that may affect clinical decisions, were observed for alpha-1-antitrypsin, beta-2-microglobulin, IgE, fibrinogen, C1-esterase inhibitor and CA125. Statistical, but not clinically significant, changes were observed for alpha-1-acid glycoprotein, C3, haptoglobin, IgA, IgG, IgM and transferrin. A significant decrease in the alpha-1 band was observed on protein electrophoresis.

Binding Sites↗
PubMed1989

Biological actions of 53 kDa nerve growth factor as studied by a blot and culture technique.

A blot and culture technique has been utilized to examine the biological actions of 53,000 Dalton (53 kDa) nerve growth factor (NGF) present in the submaxillary gland (SMG) of adult male and female mice. SMG-proteins were first resolved by sodium dodecylsulfate (SDS) polyacrylamide gel electrophoresis (PAGE) under reducing conditions and then transferred to a nitrocellulose (NTC) sheet by electroblotting. Specific areas corresponding to 53 kDa NGF were cut and cultured with the rat pheochromocytoma cell line, PC-12. NTC strips bearing the 53 kDa NGF band stimulated cell flattening and neurite formation in serum containing growth medium and augmented cell survival in serum-free growth medium. Similar results were obtained with NTC strips bearing the 13 kDa NGF band. The results suggest that 53 kDa NGF, like 13 kDa NGF, exerts both tropic and trophic actions on its target neurons.

Adrenal Gland Neoplasms↗