Biomedical subjects

Robert Duncan

Publications and source records attributed to Robert Duncan.

43 records · Page 3Linked to original sources

PubMed2002

The effects of topical vitamin K on bruising after laser treatment.

BACKGROUND: Pulsed dye laser treatment and other cosmetic procedures result in significant bruising. Claims have been made regarding the efficacy of topical vitamin K in both preventing and speeding the clearing of bruising; however, well-controlled studies are lacking. OBJECTIVE: The purpose of this study is to evaluate the effects of topical vitamin K versus placebo in the prevention and clearing of laser-induced purpura. METHODS: A total of 22 patients were enrolled in this double-blind randomized placebo-controlled study. The patients were divided into pretreatment and posttreatment groups; the 11 patients in the former group applied vitamin K cream to half of their face and vehicle alone to the other half of their face twice daily for 2 weeks before laser treatment. The latter group followed the same procedure for 2 weeks after laser treatment. On day 0, all subjects underwent laser treatment for facial telangiectases using a 585-nm pulsed dye laser. Bruising was rated by the both the patient and physician by means of a visual analogue scale on days 0, 3, 7, 10, 14, and 17. RESULTS: The side of the face treated with topical vitamin K before laser therapy showed no significant difference in bruising as compared to placebo. However, the side of the face treated with vitamin K cream after laser treatment had significantly lower scores of bruising severity when compared with the side treated with placebo. CONCLUSION: Although pretreatment with vitamin K did not prevent bruising after laser treatment, use of vitamin K cream after laser treatment did reduce the severity of bruising, particularly in the initial days of application.

Administration, Topical↗

PubMed2002

The impact of a repealed motorcycle helmet law in Miami-Dade County.

OBJECTIVE: To study the impact of helmet nonuse in motorcycle crashes after the repeal of a mandatory helmet law in the state of Florida. METHODS: We prospectively studied all patients evaluated at the University of Miami/Jackson Memorial Medical Center from July 1, 2000, through December 31, 2000, involved in motorcycle crashes, and compared them with those seen during the same time period the year before the helmet law change. RESULTS: In 1999, before the repeal of the helmet law, there were 52 cases evaluated at our center compared with 94 after the law change. Helmet usage decreased from 1999 (83%) to 2000 (56%). The number of brain injuries (Abbreviated Injury Scale score > or = 2) during this same time period increased from 18 to 35, and the number of fatalities from 2 to 8. CONCLUSION: The repeal of a motorcycle helmet law significantly increased the number and severity of brain injuries admitted to our trauma center.

Accidents, Traffic↗

PubMed2002

Detection of spinal dural arteriovenous fistulae with MR imaging and contrast-enhanced MR angiography: sensitivity, specificity, and prediction of vertebral level.

BACKGROUND AND PURPOSE: MR imaging and contrast-enhanced MR angiography have been used to detect evidence of spinal dural arteriovenous fistulae (AVF); however, the sensitivity and specificity of these techniques have not been shown. The purpose of this study was to establish the sensitivity, specificity, and accuracy of MR imaging alone compared with MR imaging plus MR angiography in determining whether dural AVF are present and to establish the accuracy of MR angiography in predicting fistula level. METHODS: Twenty patients with surgically proven dural AVF (diagnosed with radiographic digital subtraction angiography) and 11 control patients who had normal digital subtraction angiography findings underwent routine MR imaging plus 3D contrast-enhanced MR angiography of the spine. Images were reviewed in two stages (stage I, MR images only; stage II, MR images plus MR angiograms) by three neuroradiologists who were blinded to the final diagnoses. RESULTS: The sensitivity, specificity, and accuracy of the three reviewers in detecting the presence of fistulae ranged from 85% to 90%, from 82% to 100%, and from 87% to 90%, respectively, for stage I, compared with values of 80% to 100%, 82%, and 81% to 94%, respectively, for stage II. For each reviewer, there was no significant difference between the values for stages I and II; however, among the reviewers, one of the more experienced neuroradiologists had significantly greater sensitivity than a less experienced neuroradiologist for stage II. On average, the percentage of true positive results for which the correct fistula level was predicted increased from 15% for stage I to 50% for stage II, and the correct level +/- one level was predicted in 73% for stage II. MR evidence of increased intradural vascularity was significantly greater in patients with dural AVF. CONCLUSION: The addition of MR angiography to standard MR imaging of the spine may improve sensitivity in the detection of spinal dural fistulae. The principal benefit of MR angiography is in the improved localization of the vertebral level of the fistula, which potentially expedites the subsequent digital subtraction angiography study.

Adult↗

PubMedDate not supplied

Regulation of interleukin-2-induced vascular leak syndrome by targeting CD44 using hyaluronic acid and anti-CD44 antibodies.

Previous studies from our laboratory demonstrated that CD44 knockout mice exhibit marked decrease in interleukin (IL)-2-induced vascular leak syndrome (VLS), thereby suggesting a role for CD44 in VLS. In the current study, we tested whether treatment with mAbs against CD44 or hyaluronic acid (HA), the ligand for CD44, can abrogate IL-2-induced VLS. Interestingly, administration of HA caused a marked increase in IL-2-induced VLS in the lungs and liver of C57BL/6 mice. In contrast, use of anti-CD44 mAbs reduced IL-2-induced VLS in the lungs and liver. Treatment with HA enhanced the IL-2-induced edema and lymphocytic infiltration in these organs and caused marked increase in IL-2-induced lymphokine-activated killer (LAK) cell activity, whereas administration of anti-CD44 mAbs caused a significant decrease in edema and LAK activity but similar levels of lymphocytic infiltration. Anti-CD44 mAbs, but not HA caused marked downregulation of CD44 expression on LAK cells. These studies demonstrate that molecular targeting of CD44 may serve as a useful tool to selectively alter the LAK activity and to prevent endothelial cell injury induced by IL-2.

Animals↗

PubMedDate not supplied

Psychosocial profiles of people with pain associated with spinal cord injury: identification and comparison with other chronic pain syndromes.

OBJECTIVES: The objectives of the study were to: (1) identify psychosocial profiles of people with pain associated with spinal cord injuries (SCI), and (2) compare the psychosocial profiles with other chronic pain syndromes. METHODS: History questionnaires and the Multidimensional Pain Inventory (MPI) were mailed to 159 persons with chronic pain and SCIs (SCICP) and 120 (75.5%) agreed to participate. RESULTS: Cluster analysis of MPI scores identified 2 subgroups of SCICP. One (42.5%) was characterized by high Pain Severity (PS), Affective Distress (AD), Life Interference (LI), and low Life Control (LC) similar to a previously identified cluster labeled Dysfunctional. The second (57.5%) was characterized by low PS, AD, LI, and high levels of LC and activity (GA), similar to the Adaptive Copers (AC) cluster identified in previous studies with the exception that the scores were lower on Support (S), Solicitous Responses (SR), and Negative Responses (NR) and higher on Distracting Responses (DR). Both subgroups were similar to those observed in other chronic pain syndromes (CPSs). People with SCIs differed significantly from heterogeneous chronic pain and chronic headaches in that they indicated less inference of pain with activities. They also scored lower on S. SCICP reported comparable levels of LI, LC, AD, S, SR, but greater levels of PS compared with a group of people with post-polio syndrome. DISCUSSION: The similarities and differences between SCI and other CPSs suggest that although a general measure assessing psychosocial impact can be used across pain syndromes, it is important to use different norms for comparison of particular pain syndromes. The failure to identify a subgroup of patients characterized by low levels of S and high levels of NR, and the low SR and DR for SCICP compared with other CPSs warrants examination.

Adaptation, Psychological↗

PubMedDate not supplied

Presumed and confirmed striatocapsular brain infarctions in six dogs.

OBJECTIVE: To describe the clinical and diagnostic features of the canine sensorimotor syndrome caused by striatocapsular brain infarctions (SCI). ANIMALS STUDIED: Six dogs with diagnostic imaging or postmortem evidence of SCI. PROCEDURES: Medical records of dogs with SCI were retrospectively reviewed and the signalment, history, clinical signs, antemortem clinicopathologic test results, diagnostic imaging findings, case outcomes, and pathologic findings recorded. RESULTS: All dogs had an acute onset of nonprogressive homonymous visual field deficits and contralateral general proprioceptive (GP) deficits. Contralateral hemiparesis and facial hypalgesia were noted in 5/6 dogs. CT scans were normal in 2/4 dogs, and revealed poorly defined hypoattenuating lesions in the subcortical white matter in two dogs. MRI exams were performed in 5/6 dogs and revealed unilateral, variably sized, striatocapsular lesions consistent with nonhemorrhagic infarctions. Diagnostic imaging (6/6) and postmortem examinations (2/6) suggested that SCI resulted from lesions in the vascular territories of the rostral choriodal (6/6) and lenticulostriate arteries (2/6). Diseases predisposing to infarction were not identified in 5/6 dogs. Improvements in mentation, behavior, proprioceptive deficits, and hemiparesis were seen in surviving dogs, but persistent, symptomatic sensory deficits were noted during the follow-up period. CONCLUSIONS: SCI should be considered as a differential diagnosis for dogs with acute onset, nonprogressive homonymous hemianopia, contralateral GP deficits or hemiparesis, and facial hypalgesia. MRI is the preferred modality for the antemortem imaging diagnosis of SCI. Although partial recovery occurred in all surviving dogs, visual and facial sensory disturbances persisted.

Animals↗

PubMedDate not supplied

A strategy for involving on-campus and distance students in a nursing research course.

BACKGROUND: Teaching research at the undergraduate level can be a challenge. This is particularly true for distance education courses, in which students often feel isolated from each other and from faculty. Faculty teaching on-campus and distance education research courses designed a student research project and a method for bringing distance and on-campus students together to present their research findings. METHOD: By actively engaging students in the research process and providing an on-campus research day for the presentation of student posters (Year 1) and research papers (Year 2), course faculty were able to achieve their two goals of directly involving students in the nursing research process and creating a greater student sense of belonging within the college learning community. RESULTS: Statistical analysis of an evaluation survey among on-site and off-site registered nurse to bachelor of science in nursing students indicated both groups ranked the Year 1 poster research day as good to very good. Students attending the Year 2 research day, where they presented papers, ranked the day as good. Statistical analysis indicated a significant difference between the two research days, with a clear student preference for posters. CONCLUSION: Students valued their active participation in the research process and the opportunity to get together and present their work. However, students clearly preferred a poster presentation format to presenting their findings as a research paper.

Education, Distance↗