Objective Cerebral autoregulation （CA） is the mechanism by which constant cerebral blood flow is maintained despite changes in cerebral perfusion pressure. CA can be evaluated by dynamic monitoring of cerebral blood...Objective Cerebral autoregulation （CA） is the mechanism by which constant cerebral blood flow is maintained despite changes in cerebral perfusion pressure. CA can be evaluated by dynamic monitoring of cerebral blood flow velocity （CBFV） with transcranial Doppler sonography （TCD）. The present study aimed to explore CA in chronic anxiety. Methods Subjects with Hamilton anxiety scale scores 〉14 were enrolled and the dynamic changes of CBFV in response to an orthostatic challenge were investigated using TCD. Results In both the anxious and the healthy subjects, the mean CBFV was significantly lower in the upright position than when supine. However, the CBFV changes from supine to upright differed between the anxious and the healthy groups. Anxious subjects showed more pronounced decreases in CBFV with abrupt standing. Conclusion Our results indicate that cerebrovascular modulation is compromised in chronic anxiety; anxious subjects have some insufficiency in maintaining cerebral perfusion after postural change. Given the fact that anxiety and impaired CA are associated with cardiovascular disease, early ascertainment of compromised cerebrovascular modulation using TCD might suggest interventional therapies in the anxious population, and improve the primary prevention of cardiovascular disease.展开更多
Microcirculation of the peripheral nerve is necessary for neural growth and regeneration. However, technical limitations have limited studies in this area. The few studies conducted have concerned active exercise effe...Microcirculation of the peripheral nerve is necessary for neural growth and regeneration. However, technical limitations have limited studies in this area. The few studies conducted have concerned active exercise effects on microcirculation of the peripheral nerve. Using an animal experiment, this study evaluated the effect of swimming training on microcirculation of injured peripheral nerve by laser Doppler flowmetry. The results showed that the blood vessel at the distal end of the peripheral nerve was the main blood supply for the nerve, and the internal blood supply for the nerve had strong compensatory ability. Swimming training promoted the functional recovery of rats with sciatic nerve injury and the regeneration of myelin sheath and blood vessels, but had no impact on neural blood flow.展开更多
AIM： To estimate the characteristics of Color Doppler findings and the results of hepatic radionuclide angiography （HRA） in secondary Hodgkin＇s hepatic lymphoma. METHODS： The research included patients with a dia...AIM： To estimate the characteristics of Color Doppler findings and the results of hepatic radionuclide angiography （HRA） in secondary Hodgkin＇s hepatic lymphoma. METHODS： The research included patients with a diagnosis of Hodgkin＇s lymphoma with metastatic focal lesions in the liver and controls. Morphologic characteristics of focal liver lesions and hemodynamic parameters were examined by pulsed and Color Doppler in the portal, hepatic and splenic veins were examined. Hepatic perfusion index （HPI） estimated by HRA was calculated. was observed. Lesions were mostly hypoechoic and mixed, solitary or multiple. Some of the patients presented with dilated splenic veins and hepatofugal blood flow. A pulse wave was registered in the centre and at the margins of lymphoma. The average velocity of the pulse wave was higher at the margins （P 〉 0.05）. A continuous venous wave was found only at the margins of lymphoma. There was no linear correlation between lymphoma size and velocity of pulse and continuous wave （r = 390, P 〈 0.01）. HPI was significantly lower in patients with lymphomas than in controls （P 〈 0.05）, pointing out increased arterial perfusion in comparison to portal perfusion. CONCLUSION： Color Doppler ultrasonography is a sensitive method for the detection of neovascularization in Hodgkin＇s hepatic lymphoma and estimation of its intensity. Hepatic radionuclide angiography can additionally help in the assesment of vascularisation of liver lesions.展开更多
Background Chronic heart failure is a significant cause of cardiovascular morbidity and mortality. This study tested the hypothesis that restrictive filling pattern may provide useful prognostic data for identifying p...Background Chronic heart failure is a significant cause of cardiovascular morbidity and mortality. This study tested the hypothesis that restrictive filling pattern may provide useful prognostic data for identifying patients with chronic heart failure at high risk of all-cause cardiac death.Methods Ninety patients with chronic heart failure [ 70 men and 20 women, mean age (58.1 ± 11.6) years] were investigated and followed for (18. 8 ±7. 9) months. During this period, 14 patients died of progressive pump failure, 12 patients underwent heart transplantation, 5 patients died suddenly, and 2 patients died of acute myocardial infarction. A new criterion, the restrictive filling index (RFI), was designed to subgroup patients into a restrictive and a nonrestrictive group.Results Patients with restrictive filling pattern had a more severe left ventricular dysfunction and a higher cardiac mortality. Analysis by the Kaplan-Meier method revealed that patients in the RFI≥1 and RFI <1 groups had a cardiac events-free survival rate of 52% versus 94% at 1 year, and 27. 5% versus 92% at 2 years, respectively. The multivariate Cox proportional hazard model selected RFI as the most powerful prognostic factor (x2 =8. 8017, P=0. 0030) for all-cause cardiac death.Conclusion These results indicate that RFI is a simple, noninvasive, and specific clinical predictor for adult chronic heart failure patients who are at a high risk for all-cause cardiac death.展开更多
Optical Doppler Tomography (ODT) provides a novel method to measure the blood flow velocity in vessels with the diameter at micrometer scale. Rats with cranial window are used as a model, and the changes in the blood ...Optical Doppler Tomography (ODT) provides a novel method to measure the blood flow velocity in vessels with the diameter at micrometer scale. Rats with cranial window are used as a model, and the changes in the blood flow velocity of cerebral arterioles in sensory cortex are measured in real time with an established ODT system, under electrical stimulation and drug administration. The results show significant differences in the blood flow velocity between experimental groups and control groups, demonstrating the feasibility of ODT in the cerebral microcircula- tion study. Compared with the conventional Doppler ultrasound, ODT provides much higher spatial resolution, and thus holds a promising future in the application of the cerebral microcirculation study, especially in the observation of the blood flow velocity in micrometer scale vessels.展开更多
基金supported by grants from China Scholarship Council
文摘Objective Cerebral autoregulation （CA） is the mechanism by which constant cerebral blood flow is maintained despite changes in cerebral perfusion pressure. CA can be evaluated by dynamic monitoring of cerebral blood flow velocity （CBFV） with transcranial Doppler sonography （TCD）. The present study aimed to explore CA in chronic anxiety. Methods Subjects with Hamilton anxiety scale scores 〉14 were enrolled and the dynamic changes of CBFV in response to an orthostatic challenge were investigated using TCD. Results In both the anxious and the healthy subjects, the mean CBFV was significantly lower in the upright position than when supine. However, the CBFV changes from supine to upright differed between the anxious and the healthy groups. Anxious subjects showed more pronounced decreases in CBFV with abrupt standing. Conclusion Our results indicate that cerebrovascular modulation is compromised in chronic anxiety; anxious subjects have some insufficiency in maintaining cerebral perfusion after postural change. Given the fact that anxiety and impaired CA are associated with cardiovascular disease, early ascertainment of compromised cerebrovascular modulation using TCD might suggest interventional therapies in the anxious population, and improve the primary prevention of cardiovascular disease.
基金the Military Project during "Tenth Five-Year Plan" Period, No.200626Z000058
文摘Microcirculation of the peripheral nerve is necessary for neural growth and regeneration. However, technical limitations have limited studies in this area. The few studies conducted have concerned active exercise effects on microcirculation of the peripheral nerve. Using an animal experiment, this study evaluated the effect of swimming training on microcirculation of injured peripheral nerve by laser Doppler flowmetry. The results showed that the blood vessel at the distal end of the peripheral nerve was the main blood supply for the nerve, and the internal blood supply for the nerve had strong compensatory ability. Swimming training promoted the functional recovery of rats with sciatic nerve injury and the regeneration of myelin sheath and blood vessels, but had no impact on neural blood flow.
基金Supported by The grant of the Republic of Science of Serbia (M145033,Chief investigatior:Professor Vladimir Obradovic)
文摘AIM： To estimate the characteristics of Color Doppler findings and the results of hepatic radionuclide angiography （HRA） in secondary Hodgkin＇s hepatic lymphoma. METHODS： The research included patients with a diagnosis of Hodgkin＇s lymphoma with metastatic focal lesions in the liver and controls. Morphologic characteristics of focal liver lesions and hemodynamic parameters were examined by pulsed and Color Doppler in the portal, hepatic and splenic veins were examined. Hepatic perfusion index （HPI） estimated by HRA was calculated. was observed. Lesions were mostly hypoechoic and mixed, solitary or multiple. Some of the patients presented with dilated splenic veins and hepatofugal blood flow. A pulse wave was registered in the centre and at the margins of lymphoma. The average velocity of the pulse wave was higher at the margins （P 〉 0.05）. A continuous venous wave was found only at the margins of lymphoma. There was no linear correlation between lymphoma size and velocity of pulse and continuous wave （r = 390, P 〈 0.01）. HPI was significantly lower in patients with lymphomas than in controls （P 〈 0.05）, pointing out increased arterial perfusion in comparison to portal perfusion. CONCLUSION： Color Doppler ultrasonography is a sensitive method for the detection of neovascularization in Hodgkin＇s hepatic lymphoma and estimation of its intensity. Hepatic radionuclide angiography can additionally help in the assesment of vascularisation of liver lesions.
文摘Background Chronic heart failure is a significant cause of cardiovascular morbidity and mortality. This study tested the hypothesis that restrictive filling pattern may provide useful prognostic data for identifying patients with chronic heart failure at high risk of all-cause cardiac death.Methods Ninety patients with chronic heart failure [ 70 men and 20 women, mean age (58.1 ± 11.6) years] were investigated and followed for (18. 8 ±7. 9) months. During this period, 14 patients died of progressive pump failure, 12 patients underwent heart transplantation, 5 patients died suddenly, and 2 patients died of acute myocardial infarction. A new criterion, the restrictive filling index (RFI), was designed to subgroup patients into a restrictive and a nonrestrictive group.Results Patients with restrictive filling pattern had a more severe left ventricular dysfunction and a higher cardiac mortality. Analysis by the Kaplan-Meier method revealed that patients in the RFI≥1 and RFI <1 groups had a cardiac events-free survival rate of 52% versus 94% at 1 year, and 27. 5% versus 92% at 2 years, respectively. The multivariate Cox proportional hazard model selected RFI as the most powerful prognostic factor (x2 =8. 8017, P=0. 0030) for all-cause cardiac death.Conclusion These results indicate that RFI is a simple, noninvasive, and specific clinical predictor for adult chronic heart failure patients who are at a high risk for all-cause cardiac death.
基金the National Hi-Tech Research and Development Program of China (863 Program)(Grant No. 2006AA02Z4E0)the National Natu-ral Science Foundation of China (Grant Nos. 60378041, 60478040, 60878057 and 30770685)+1 种基金the Program for New Century Excellent Talents in University (Grant No. NCET-04-0528)the Opening Project of MOE Key Laboratory of Laser Life Science, South China Normal University
文摘Optical Doppler Tomography (ODT) provides a novel method to measure the blood flow velocity in vessels with the diameter at micrometer scale. Rats with cranial window are used as a model, and the changes in the blood flow velocity of cerebral arterioles in sensory cortex are measured in real time with an established ODT system, under electrical stimulation and drug administration. The results show significant differences in the blood flow velocity between experimental groups and control groups, demonstrating the feasibility of ODT in the cerebral microcircula- tion study. Compared with the conventional Doppler ultrasound, ODT provides much higher spatial resolution, and thus holds a promising future in the application of the cerebral microcirculation study, especially in the observation of the blood flow velocity in micrometer scale vessels.
