ABSTRACT
BACKGROUND: Turbulent blood flow caused by arterial stenosis can induce platelet activation and aggregation, which subsequently participate in arterial thromboembolic events. OBJECTIVE: To test the hypothesis that platelet activation (expressed by CD62p) is enhanced in cerebral vs systemic circulation in patients with severe internal carotid artery (ICA) stenosis. METHODS: Platelet CD62p expression was prospectively measured using flow cytometry in 35 consecutive symptomatic patients with severe ICA stenosis and in 20 at-risk control subjects who underwent both coronary and cerebral angiographic studies due to angina pectoris and suspicious vertebral artery or intracranial artery stenosis. The CD62p expression was also evaluated in 20 healthy subjects. Blood samples were first drawn from the right internal jugular vein (cerebral circulation) and right femoral vein (systemic circulation) before extra- and intracerebral angiographic examination of both patients and at-risk control subjects and again at 40 minutes after ICA stenting. Clopidogrel was administered to the patients following the second blood sampling. RESULTS: Systemic CD62p expression was higher in patients than in both the healthy and at-risk control subjects (both p < 0.0001). Additionally, cerebral CD62p expression was higher in patients than in at-risk control subjects (p < 0.0001) prior to intervention. Moreover, CD62p expression was higher in cerebral circulation than in systemic circulation in the patients (p < 0.0001) before ICA stenting. However, CD62p expression was less enhanced in cerebral circulation than in systemic circulation after ICA stenting (p < 0.0001). Furthermore, CD62p expression was decreased after 3 months of follow-up (p < 0.0001). CONCLUSIONS: Compared to systemic CD62p expression, cerebral CD62p expression was more enhanced prior to ICA stenting and was less enhanced after ICA stenting in patients with severe ICA stenosis.
Subject(s)
Carotid Artery, Internal/metabolism , Carotid Stenosis/blood , Platelet Activation/physiology , Aged , Brain/diagnostic imaging , Brain/metabolism , Carotid Artery, Internal/diagnostic imaging , Carotid Stenosis/diagnostic imaging , Female , Humans , Male , Middle Aged , P-Selectin/biosynthesis , Prospective Studies , RadiographyABSTRACT
PIP: A modification of the randomized response technique developed by S.L. Warner to obtain valid responses to sensitive interview questions was applied in Taoyuan, Taiwan, in an effort to determine the incidence of abortion. This article assesses the feasibility of using the technique in a cultural context different from that of the United States where it originated. The technique allows the respondent to answer 1 of 2 questions selected on the basis of probability without divulging the information to the interviewer. 2497 currently married women aged 15 to 49 were divided into 2 groups, one of which was asked directly about their abortion experience while the technique was used with the other group. It was estimated that 28.2% of women using the technique had undergone at least 1 induced abortion. Only 12.7% of women who responded to a direct question admitted to having had an aboution. About 32% of respondents refused to cooperate in the study of the technique, and cooperation was found to be closely related to education, with age and extent of knowledge of abortion and family planning also related to refusal. The fact that the differences in rates of the 2 groups is in the expected direction suggests that use of the techniques can help reduce underestimation.^ieng
