1.Model experiment and numerical simulation of marginal pressure in the flow field downstream of the stenostic vessel in vitro.
Yingqiang GUO ; Yingkan SHI ; Jianmin ZHANG ; Weilin XUE ; Shanjun LIU
Journal of Biomedical Engineering 2006;23(2):300-303
For the defects of interpreting the relationship between the distribution and severity of vascular stenostic disease and the low shear stress, the study focus on and explore the rules of the pressure distribution and variation downstream of the stenostic vessel with the numerical simulation and the hydrodynamic model of turbulent flow separation area for in vitro experiment. The results reveal that there is a good compatibility between the model experiment and the numerical simulation; there exists a marked pressure decrease downstream of the stenosis. And the distribution area of low pressure is similar to the characteristic distribution of the stenostic vessel diseases. The study suggested that the numerical simulation can be applied in the study of micro-flow field; the presure distribution and variatioin downstream of the stenostic vessel maybe another factor to trigger the pathogenesis of vessel stenostic diseases.
Blood Flow Velocity
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physiology
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Blood Pressure
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physiology
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Constriction, Pathologic
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physiopathology
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Humans
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Models, Biological
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Vascular Diseases
;
physiopathology
2.Design and adjustment of a hydrodynamic model of turbulent flow separation area for in vitro experiment on the downstream of tubal stenosis.
Yingqiang GUO ; Yingkang SHI ; Weilin XUE ; Ke LIN ; Shanjun LIU ; Jianmin ZHANG ; Wei MENG
Journal of Biomedical Engineering 2005;22(1):38-42
This paper reports the establishment of a model of turbulent flow separation area for experiment on the downstream of tubal stenosis, and adjust it to cooperate with the velocity and turbulent shear stress (TSS) detection by means of the particle image velocimetry (PIV), and with the pressure detection of pressure sensor in vitro. The velocity, TSS and wall pressure characteristics of the downstream of tubal stenosis were quantitatively detected and analyzed via the PIV and pressure sensor. And the hydrodynamic characteristics of the velocity, TSS and wall pressure in the flow separation area were primarily understood. The model can cooperate smoothly with the PIV and pressure sensor to detect the velocity, TSS and wall pressure; there exist low velocity, low TSS and low pressure in the flow separation area downstream of tubal stenosis.
Blood Flow Velocity
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physiology
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Computer Simulation
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Constriction, Pathologic
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physiopathology
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Heart Valve Diseases
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physiopathology
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Models, Cardiovascular
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Rheology
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Stress, Mechanical
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Vascular Diseases
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physiopathology
3.Mechanisms of adiponectin protection against diabetes-induced vascular endothelial injury.
Acta Physiologica Sinica 2019;71(3):485-490
The incidence and mortality rates of diabetes with cardiovascular complications are continually rising, and diabetic cardiovascular disease is becoming a major public health issue that threatens human health. Acute endothelial dysfunction and chronic cellular damage caused by diabetes are important risk factors for diabetic cardiovascular disease and related mortality. Adiponectin is an adipocyte-derived molecule with significant cytoprotective effects, including the protection against diabetes-induced vascular endothelial injury. Here we review the mechanisms of adiponectin protective effects on acute vascular endothelial dysfunction and chronic structural damage induced by diabetes.
Adiponectin
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physiology
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Cardiovascular Diseases
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complications
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Diabetes Mellitus
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pathology
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Endothelium, Vascular
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physiopathology
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Humans
5.Development of Korean Academy of Medical Sciences Guideline for Rating Physical Disability of Upper Extremity.
Jung Ho PARK ; Hee Chun KIM ; Jae Hoon LEE ; Jin Soo KIM ; Si Young ROH ; Cheol Ho YI ; Yoon Kyoo KANG ; Bum Sun KWON
Journal of Korean Medical Science 2009;24(Suppl 2):S288-S298
While the lower extremities support the weight and move the body, the upper extremities are essential for the activities of daily living, which require many detailed movements. Therefore, a disability of the upper extremity function should include a limitation of all motions of the joints and sensory loss, which affects the activities. In this study, disabilities of the upper extremities were evaluated according to the following conditions: 1) amputation, 2) joint contracture, 3) diseases of upper extremity, 4) weakness, 5) sensory loss of the finger tips, and 6) vascular and lymphatic diseases. The order of 1) to 6) is the order of major disability and there is no need to evaluate a lower order disability when a higher order one exists in the same joint or a part of the upper extremity. However, some disabilities can be either added or substituted when there are special contributions from multiple disabilities. An upper extremity disability should be evaluated after the completion of treatment and full adaptation when further functional changes are not expected. The dominance of the right or left hand before the disability should not be considered when there is a higher rate of disability.
*Disability Evaluation
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Hand Injuries/classification/physiopathology
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Humans
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Joint Diseases/classification/physiopathology
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Korea
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Muscles/physiopathology
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Peripheral Vascular Diseases/classification/physiopathology
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Program Development
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Sensation/physiology
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Severity of Illness Index
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Upper Extremity/*physiopathology
6.Pericyte Plasticity in the Brain.
Gabryella S P SANTOS ; Luiz A V MAGNO ; Marco A ROMANO-SILVA ; Akiva MINTZ ; Alexander BIRBRAIR
Neuroscience Bulletin 2019;35(3):551-560
Cerebral pericytes are perivascular cells that stabilize blood vessels. Little is known about the plasticity of pericytes in the adult brain in vivo. Recently, using state-of-the-art technologies, including two-photon microscopy in combination with sophisticated Cre/loxP in vivo tracing techniques, a novel role of pericytes was revealed in vascular remodeling in the adult brain. Strikingly, after pericyte ablation, neighboring pericytes expand their processes and prevent vascular dilatation. This new knowledge provides insights into pericyte plasticity in the adult brain.
Animals
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Brain
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blood supply
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physiology
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physiopathology
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Brain Diseases
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physiopathology
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Capillaries
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physiology
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Cellular Microenvironment
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Diabetic Retinopathy
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physiopathology
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Endothelial Cells
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physiology
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Humans
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Pericytes
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physiology
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Vascular Remodeling
7.Advances in study of vascular endothelial growth factor and thyroid disease.
Journal of Biomedical Engineering 2012;29(4):784-787
The basic function of vascular endothelial growth factor (VEGF) is to promote vascular growth. Recent studies show that VEGF plays a vital role in various thyroid diseases through prompting angiogenesis. But the function of VEGF and specific change condition in different thyroid disease still needs further explorations. This review mainly focuses on the molecular characteristics and clinical application of VEGF.
Angiogenesis Inducing Agents
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Animals
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Graves Disease
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metabolism
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physiopathology
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Humans
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Thyroid Diseases
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metabolism
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physiopathology
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Thyroid Gland
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blood supply
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Thyroid Neoplasms
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metabolism
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physiopathology
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Thyroiditis
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metabolism
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physiopathology
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Vascular Endothelial Growth Factor A
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metabolism
9.Distribution of systemic vascular resistance disorders and its related factors in Hebei province.
Xiao-mei ZHOU ; Bao-shen QI ; Cheng-li XU ; Shao-mei HAN ; Guang-jin ZHU
Acta Academiae Medicinae Sinicae 2006;28(2):249-252
OBJECTIVETo analyze the distribution features of systemic vascular resistance (SVR) disorder in healthy subjects in Hebei province.
METHODSSVR and systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke index (SI), left ventricular ejection time (LVET), left cardiac work (LCW) and cardiovascular function were determined with Bioz. com Cardio Dynamics. Total cholesterol (TC), triglyceride (TG) and influencing factor were tested by automated hematology analyzer in 999 healthy subjects living in Hebei province.
RESULTSSVR disorder gradually increased with the ageing in healthy subjects and the prevalences of SVR disorders was higher among females than among males (P < 0.001). SVR was positively correlated with SBP, DBP, MAP, PP, LVET, body mass index (BMI), TC, and TG, and was inversely associated with HR, CO, CI, SV, SI, LCW, and arterial compliance (AC). CO and MAP were independent influencing factors with SVR.
CONCLUSIONSVR disorder is associated with age, sex, and blood pressure in populations in Hebei province and may be a marker of vascular injury.
Adolescent ; Adult ; Age Factors ; Aged ; Blood Pressure ; Body Mass Index ; Cardiac Output ; Female ; Hemodynamics ; physiology ; Humans ; Male ; Middle Aged ; Risk Factors ; Sex Factors ; Vascular Capacitance ; Vascular Diseases ; physiopathology ; Vascular Resistance
10.Cardiovascular benefits of vitamin D.
Jinghui DONG ; Chi Wai LAU ; Siu Ling WONG ; Yu HUANG
Acta Physiologica Sinica 2014;66(1):30-36
Vitamin D is essential for maintaining calcium and phosphate homeostasis, and vitamin D analogues have been prescribed to treat osteoporosis and hyperparathyroidism. Emerging evidence suggests that cardiovascular and chronic kidney diseases are closely associated with vitamin D deficiency resulting from either decreased sunshine exposure or inadequate intake. Vitamin D is through stimulating vitamin D receptor to form a transcriptional complex with cofactors to modulate approximately 3% gene transcription. For example, renin, matrix metalloprotease, and tumor necrosis factor-α are regulated by vitamin D. Both experimental and clinical studies support the health benefits of vitamin D in the cardiovascular system, and such benefits include protecting cardiac function, lowering blood pressure, improving endothelial function, inhibiting oxidative stress, and reducing the activity of renin-angiotensin system. This article will briefly review the cardiovascular benefits of vitamin D and its bioactive analogues and discuss the novel cellular and molecular mechanisms accounting for cardiovascular protection.
Blood Pressure
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Calcium
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physiology
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Cardiovascular Diseases
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physiopathology
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Cardiovascular Physiological Phenomena
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Endothelium, Vascular
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physiology
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physiopathology
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Humans
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Oxidative Stress
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Receptors, Calcitriol
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physiology
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Renin-Angiotensin System
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Vitamin D
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analogs & derivatives
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physiology
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Vitamin D Deficiency
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physiopathology