Basal Ganglia and Brainstem Located Cerebral Microbleeds Contributed to Gait Impairment in Patients with Cerebral Small Vessel Disease.

BACKGROUND: The mechanism of gait disorder in patients with cerebral small vessel disease (CSVD) remains unclear. Limited studies have compared the effect of cerebral microbleeds (CMBs) and lacunes on gait disturbance in CSVD patients in different anatomical locations. OBJECTIVE: To investigate the relationship of quantitative gait parameters with varied anatomically located MRI imaging markers in patients with CSVD. METHODS: Quantitative gait tests were performed on 127 symptomatic CSVD patients all with diffuse distributed white matter hyperintensities (WMHs). CMBs and lacunes in regard to anatomical locations and burdens were measured. The correlation between CSVD imaging markers and gait parameters was evaluated using general linear model analysis. RESULTS: Presence of CMBs was significantly associated with stride length (ß= -0.098, p = 0.0272) and right step length (ß= -0.054, p = 0.0206). Presence of CMBs in basal ganglia (BG) was significantly associated with stride length and step length. Presence of CMBs in brainstem was significantly associated with gait parameters including stride length, step length, step height, and step width. Presence of lacunes in brainstem was significantly associated with gait speed (ß= -0.197, p = 0.0365). However, presence of lacunes in the other areas was not associated with worse gait performances. CONCLUSION: BG and brain stem located CMBs contributed to gait impairment in symptomatic CSVD patients.

Brief Report: Sex Differences in the Association Between Cerebrovascular Function and Cognitive Health in People Living With HIV in Urban China.

BACKGROUND: Cardiometabolic and cerebrovascular disease are strong independent contributors to cognitive impairment in people living with HIV. Data suggest that cardiovascular risk may play a greater role in cognitive health in women than in men with HIV. METHODS: We performed a cross-sectional study of 104 participants with virologically suppressed HIV from 2 clinics in urban China. Participants underwent neuropsychological testing from which we calculated T scores globally and in 5 cognitive domains. We assessed cerebral vasoreactivity of the middle cerebral arteries in response to breath holding. We constructed linear regression models to determine associations between cerebrovascular and cognitive function overall and stratified by sex. RESULTS: Women were younger than men (48 versus 51 years, P = 0.053), had fewer years of education (9 years versus 12 years, P = 0.004), and fewer cardiometabolic risk factors (0 versus 1 factor, P = 0.008). In a model with all participants, cerebrovascular function was significantly associated with global cognition (2.74 higher T score per 1-point higher cerebral vasoreactivity [SE 1.30], P = 0.037). Cerebrovascular function remained significantly associated with global cognition among women (4.15 higher T score [SE 1.78], P = 0.028) but not men (1.70 higher T score [SE 1.74], P = 0.33). The relationships between cerebrovascular function and specific cognitive domains followed a similar pattern, with significant associations present among women but not men. CONCLUSIONS: Women with well-controlled HIV may be more vulnerable to the effect of cerebrovascular injury on cognitive health than men. Studies evaluating strategies to protect against cognitive impairment in people living with HIV should include adequate representation of women and stratification of analyses by sex.

Echo-Tracking Method Improves the Reliability in Flow-Mediated Dilation Assessment by Measuring Brachial Artery Reactivity.

The purpose of the study was to compare the intraobserver and interobserver reliability and agreement for measurement of flow-mediated dilation (FMD) between B-mode method and echo-tracking (ET) method. Twenty healthy volunteers (mean age, 31.6 ± 9.2 years) underwent ultrasound examination by both B-mode and ET methods. Baseline brachial artery diameter, post-cuff release diameter, and FMD percent were assessed by each sonologist on 2 consecutive days. Reliability was assessed by intraclass correlation coefficients, and Bland-Altman plots were used to visually compare measurement bias and agreement by the 2 ultrasound methods. A total of 40 pairs of data were available for analysis. Excellent intraobserver and interobserver reliability values were found for all variables assessed by the 2 methods. The intraclass correlation coefficient values were higher for ET in both intraobserver and interobserver evaluations, but only for interobserver evaluations for post-cuff release diameter and FMD was there no overlap in the 95% confidence interval. The Bland-Altman plots showed that in 95% of the measurements, the percentage difference between ET and B-mode ultrasound techniques was within 18.1%, 19.4%, and 17.3% for baseline brachial artery diameter, post-cuff release diameter, and FMD percent, respectively. The results suggest that ET and B-mode methods are reproducible in assessing the FMD. The ET method improves the reliability of FMD assessment, but we cannot determine which measurement is better for FMD.

High-frequency ultrasound evaluation of effects of early treatment with metoprolol on myocardial inflammatory cytokine expression in rats with acute myocardial infarction.

This study evaluated the effects of early treatment with ß-adrenergic blocker metoprolol on ventricular remodeling and function after acute myocardial infarction (AMI) by using high frequency ultrasound. The relationship between the efficacy and the expression level of cardiac myocardial inflammatory cytokine was examined in rats. The rat model of AMI was induced by ligating the left anterior descending artery. The surviving rats were randomly assigned to two experimental groups: MI control (MI) group and MI metoprolol (MI-B) group, with the rats undergoing sham operation serving as normal control (Sham). MI-B group was given metoprolol for 4 weeks (refer to the CCS-2 protocol) and the other two groups received equal volume of saline via intragastric (i.g.) administration. The ventricular remodeling and function were evaluated by high frequency ultrasound 4 weeks after the treatment. Then all rats were sacrificed for pathological examination and immunohistochemistrical detection of inflammatory cytokines, including IL-1ß, IL-6, IL-10 and TNF-α. Compared with the MI group, the left ventricular end-systolic dimension, end-diastolic dimension, end-systolic volume and end-diastolic volume of the MI-B group were significantly decreased (P<0.01), while the left ventricular anterior wall end-diastolic thickness, ejection fraction and fractional shortening were obviously increased (P<0.01). The conspicuous improvement in the left ventricular morphology and function was coincident with the markedly reduced TNF-α and IL-1ß expression and the increased IL-10 expression. We are led to conclude that early metoprolol treatment for AMI can regulate myocardial inflammatory cytokine expression to improve cardiac function and the underlying mechanism might be that it decreases the level of pro-inflammatory cytokines and increases the level of its anti-inflammatory counterparts in cardiac myocytes. Our study also showed that echocardiography is a useful technique for the structural and functional assessment of left ventricle after acute myocardial infarction.