1.Quantitative analysis of the effect of contact pressure on the reflection characteristics of radial pressure wave.
Junyi TAN ; Lisheng XU ; Hongming SUN ; Bowen XU ; Yongchun LI ; Yudong YAO
Journal of Biomedical Engineering 2022;39(6):1127-1132
The radial artery pulse wave contains a wealth of physiological and pathological information about the human body, and non-invasive studies of the radial artery pulse wave can assess arterial vascular elasticity in different age groups.The piezoelectric pulse wave transducers were used to non-invasively acquire radial artery pulse waves at different contact pressures in young and middle-aged and elderly populations. The radial artery waveforms were decomposed using a triangular blood flow model fitting method to obtain forward and reflected waves and calculate reflection parameters. Finally a correlation analysis and regression analysis of the contact pressure Psensor with the reflection parameters was carried out. The results showed that the reflection parameters RM, RI and Rd had a strong negative correlation with Psensor in both types of subjects, and the correlation coefficients and slopes of the regression curves were significantly different between the two types of subjects (P<0.05). Based on the results of this study, excessive contact pressure on the transducer should be avoided when detecting radial artery reflection waves in clinical practice. The results also show that the magnitude of the slope of the regression curve between the reflection parameters and the transducer contact pressure may be a potentially useful indicator for quantifying the elastic properties of the vessel.
Middle Aged
;
Aged
;
Humans
;
Blood Pressure/physiology*
;
Arteries
;
Blood Flow Velocity/physiology*
;
Elasticity
;
Pulse Wave Analysis
;
Radial Artery/physiology*
2.Mitochondrial Oxidative Stress Enhances Vasoconstriction by Altering Calcium Homeostasis in Cerebrovascular Smooth Muscle Cells under Simulated Microgravity.
Zi Fan LIU ; Hai Ming WANG ; Min JIANG ; Lin WANG ; Le Jian LIN ; Yun Zhang ZHAO ; Jun Jie SHAO ; Jing Jing ZHOU ; Man Jiang XIE ; Xin LI ; Ran ZHANG
Biomedical and Environmental Sciences 2021;34(3):203-212
Objective:
Exposure to microgravity results in postflight cardiovascular deconditioning in astronauts. Vascular oxidative stress injury and mitochondrial dysfunction have been reported during this process. To elucidate the mechanism for this condition, we investigated whether mitochondrial oxidative stress regulates calcium homeostasis and vasoconstriction in hindlimb unweighted (HU) rat cerebral arteries.
Methods:
Three-week HU was used to simulate microgravity in rats. The contractile responses to vasoconstrictors, mitochondrial fission/fusion, Ca
Results:
An increase of cytoplasmic Ca
Conclusion
The present results suggest that mitochondrial oxidative stress enhances cerebral vasoconstriction by regulating calcium homeostasis during simulated microgravity.
Animals
;
Calcium/metabolism*
;
Cerebral Arteries
;
Homeostasis
;
Male
;
Mitochondria/physiology*
;
Myocytes, Smooth Muscle/physiology*
;
Oxidative Stress
;
Rats
;
Rats, Sprague-Dawley
;
Vasoconstriction/physiology*
;
Weightlessness Simulation
3.Neuroimmune interactions and kidney disease
Sho HASEGAWA ; Tsuyoshi INOUE ; Reiko INAGI
Kidney Research and Clinical Practice 2019;38(3):282-294
The autonomic nervous system plays critical roles in maintaining homeostasis in humans, directly regulating inflammation by altering the activity of the immune system. The cholinergic anti-inflammatory pathway is a well-studied neuroimmune interaction involving the vagus nerve. CD4-positive T cells expressing β2 adrenergic receptors and macrophages expressing the alpha 7 subunit of the nicotinic acetylcholine receptor in the spleen receive neurotransmitters such as norepinephrine and acetylcholine and are key mediators of the cholinergic anti-inflammatory pathway. Recent studies have demonstrated that vagus nerve stimulation, ultrasound, and restraint stress elicit protective effects against renal ischemia-reperfusion injury. These protective effects are induced primarily via activation of the cholinergic anti-inflammatory pathway. In addition to these immunological roles, nervous systems are directly related to homeostasis of renal physiology. Whole-kidney three-dimensional visualization using the tissue clearing technique CUBIC (clear, unobstructed brain/body imaging cocktails and computational analysis) has illustrated that renal sympathetic nerves are primarily distributed around arteries in the kidneys and denervated after ischemia-reperfusion injury. In contrast, artificial renal sympathetic denervation has a protective effect against kidney disease progression in murine models. Further studies are needed to elucidate how neural networks are involved in progression of kidney disease.
Acetylcholine
;
Arteries
;
Autonomic Nervous System
;
Cholinergic Neurons
;
Homeostasis
;
Humans
;
Immune System
;
Inflammation
;
Kidney Diseases
;
Kidney
;
Macrophages
;
Nervous System
;
Neurotransmitter Agents
;
Norepinephrine
;
Optogenetics
;
Physiology
;
Receptors, Adrenergic
;
Receptors, Nicotinic
;
Reperfusion Injury
;
Spleen
;
Sympathectomy
;
Sympathetic Nervous System
;
T-Lymphocytes
;
Ultrasonography
;
Vagus Nerve
;
Vagus Nerve Stimulation
4.The expression and meaning of Hippo signaling pathway in carotid artery ligation induced arterial remodeling model of rats.
Ning ZHU ; Hao CHEN ; Xu Yong ZHAO ; Fan Hao YE ; Yi WANG
Chinese Journal of Applied Physiology 2019;35(1):23-27
OBJECTIVE:
To establish an arterial remodeling model of rats and to investigate the expression and role of Hippo signaling pathway in this model.
METHODS:
In the model group (n=40), the left common carotid artery was removed through the median incision of the neck. The 6-0 non-absorbable line was used to ligate the carotid artery near the proximal end as far as possible, completely blocking the blood flow. The common carotid artery of rats in control group (n=20) was not ligated using the operative line. After 14 days, the animals were sacrificed and the common carotid arteries were separated through the original surgical pathway and the arteries from the ligature to the distal end were collected. Arterial morphology and fibrosis were observed by HE and MASSON staining. Immunohistochemical staining was used to detect the expressions of anti-α smooth muscle actin (α-MSA) and proliferating cell nuclear antigen (PCNA) in the carotid artery. Western blot was used to detect the expressions of yes associated protein (YAP), transcriptional coactivator with PDZ-binding motif (TAZ), TEAD1, Bcl-2-like protein 4 (Bax), and B-cell lymphoma-2 (Bcl-2).
RESULTS:
Compared with the control group, the HE staining showed that the vascular remodeling was obvious, the ratio of the neointima/middle membrane was increased significantly, and the MASSON staining indicated that the fibrosis was significantly increased in model group. The immunohistochemical staining suggested that the expressions of α-SMA and PCNA were increased significantly; Western blot suggested that the expressions of YAP, TAZ, TEAD1, and Bcl-2 were increased in carotid artery of the model group. While the expression of Bax and the ratio of Bax/Bcl-2 were decreased.
CONCLUSION
A rat model of arterial remodeling mediated by carotid artery ligation was established successfully in this study. Hippo signaling pathway was proved to be activated in the arterial remodeling model induced by carotid artery ligation in rats, and might regulate the change of Bax/Bcl-2 ratio related to proliferation and apoptosis, and subsequently involved in the proliferation of smooth muscle cells to promote vascular remodeling.
Animals
;
Carotid Arteries
;
metabolism
;
Carotid Artery, Common
;
Cell Proliferation
;
Myocytes, Smooth Muscle
;
Protein-Serine-Threonine Kinases
;
metabolism
;
Rats
;
Signal Transduction
;
Vascular Remodeling
;
physiology
5.Association of MicroRNA Biogenesis Genes Polymorphisms with Ischemic Stroke Susceptibility and Post-Stroke Mortality
Jung Oh KIM ; Jinkun BAE ; Jinkwon KIM ; Seung Hun OH ; Hui Jeong AN ; In Bo HAN ; Doyeun OH ; Ok Joon KIM ; Nam Keun KIM
Journal of Stroke 2018;20(1):110-121
BACKGROUND AND PURPOSE: MicroRNA (miRNA) expression has been examined in multiple conditions, including various cancers, neurological diseases, and cerebrovascular diseases, particularly stroke. Existing evidence indicates that miRNA biosynthesis and function play crucial roles in ischemic stroke physiology and pathology. In this study, we selected six known polymorphisms in miRNA-biogenesis genes; DICER rs13078A>T, rs3742330A>G; DROSHA rs10719T>C, rs6877842G>C; Ran GTPase (RAN) rs14035C>T; exportin 5 (XPO5) rs11077A>C. METHODS: We analyzed the associations between these polymorphisms and disease status and clinical factors in 585 ischemic stroke patients and 403 controls. Genotyping was performed with the polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: The DICER rs3742330A>G (AA vs. AG+GG: adjusted odds ratio [AOR], 1.360; 95% confidence interval [CI], 1.024 to 1.807; P=0.034) and DROSHA rs10719T>C polymorphisms (TT vs. CC: AOR, 2.038; 95% CI, 1.113 to 3.730; P=0.021) were associated with ischemic stroke prevalence. During a mean follow-up of 4.80±2.11 years, 99 (5.91%) of the stroke patients died. In multivariate Cox proportional hazard regression models, a significant association was found between RAN rs14035 and survival of large artery disease patients with ischemic stroke (CC vs. TT: adjusted hazard ratio, 5.978; P=0.015). CONCLUSIONS: An association was identified between the DICER and DROSHA polymorphisms and ischemic stroke. Specifically, polymorphisms (rs3742330 and rs10719) were more common in stroke patients, suggesting that they may be associated with an increased risk of ischemic stroke.
Arteries
;
Cerebrovascular Disorders
;
Follow-Up Studies
;
GTP Phosphohydrolases
;
Humans
;
Methods
;
MicroRNAs
;
Mortality
;
Odds Ratio
;
Pathology
;
Physiology
;
Polymorphism, Genetic
;
Prevalence
;
Stroke
6.Comparison of the Haemodynamic Parameters of Venous and Arterial Coronary Artery Bypass Conduits.
Jun Mei ZHANG ; Clement Jh CHAN ; Ning KANG ; Jia Lin SOON ; Kenny Yk SIN ; Victor Tt CHAO ; Teing Ee TAN ; Chong Hee LIM ; Mathew J CHAKARAMAKKIL ; Adrian Sw OOI ; Yeow Leng CHUA ; Ru San TAN ; Liang ZHONG
Annals of the Academy of Medicine, Singapore 2016;45(8):369-372
Aged
;
Atherosclerosis
;
Case-Control Studies
;
Coronary Artery Bypass
;
methods
;
Coronary Artery Disease
;
surgery
;
Female
;
Hemodynamics
;
physiology
;
Humans
;
Male
;
Mammary Arteries
;
physiology
;
transplantation
;
Middle Aged
;
Pulsatile Flow
;
Radial Artery
;
physiology
;
transplantation
;
Rheology
;
Saphenous Vein
;
physiology
;
transplantation
;
Shear Strength
;
Stress, Mechanical
;
Vascular Patency
;
physiology
7.Effects of Omega-3 Fatty Acids on Erectile Dysfunction in a Rat Model of Atherosclerosis-induced Chronic Pelvic Ischemia.
Ji Sung SHIM ; Dae Hee KIM ; Jae Hyun BAE ; Du Geon MOON
Journal of Korean Medical Science 2016;31(4):585-589
The aim of this study was to investigate whether the omega-3 fatty acids help to improve erectile function in an atherosclerosis-induced erectile dysfunction rat model. A total of 20 male Sprague-Dawley rats at age 8 weeks were divided into three groups: Control group (n = 6, untreated sham operated rats), Pathologic group (n = 7, untreated rats with chronic pelvic ischemia [CPI]), and Treatment group (n = 7, CPI rats treated with omega-3 fatty acids). For the in vivo study, electrical stimulation of the cavernosal nerve was performed and erectile function was measured in all groups. Immunohistochemical antibody staining was performed for transforming growth factor beta-1 (TGF-β1), endothelial nitric oxide synthase (eNOS), and hypoxia inducible factor 1-alpha (HIF-1α). In vivo measurement of erectile function in the Pathologic group showed significantly lower values than those in the Control group, whereas the Treatment group showed significantly improved values in comparison with those in the Pathologic group. The results of western blot analysis revealed that systemically administered omega-3 fatty acids ameliorated the cavernosal molecular environment. Our study suggests that omega-3 fatty acids improve intracavernosal pressure and have a beneficial role against pathophysiological consequences such as fibrosis or hypoxic damage on a CPI rat model, which represents a structural erectile dysfunction model.
Animals
;
Atherosclerosis/*complications
;
Blotting, Western
;
Carotid Arteries/physiology
;
Chronic Disease
;
Disease Models, Animal
;
Electric Stimulation
;
Fatty Acids, Omega-3/*pharmacology
;
Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
;
Ischemia/etiology/*pathology
;
Male
;
Nitric Oxide Synthase Type III/metabolism
;
Penile Erection/*drug effects
;
Penis/metabolism/pathology
;
Rats
;
Rats, Sprague-Dawley
;
Transforming Growth Factor beta1/metabolism
8.A New Flow-Diverter (the FloWise): In-Vivo Evaluation in an Elastase-Induced Rabbit Aneurysm Model.
Byung Moon KIM ; Dong Joon KIM ; Dong Ik KIM
Korean Journal of Radiology 2016;17(1):151-158
OBJECTIVE: We aimed to evaluate the efficacy and safety of a newly developed, partially retrievable flow-diverter (the FloWise) in an elastase-induced rabbit aneurysm model. MATERIALS AND METHODS: We developed a partially retrievable flow diverter composed of 48 strands of Nitinol and platinum wire. The FloWise is compatible with any microcatheter of 0.027-inch inner diameter, and is retrievable up to 70% deployment. The efficacy and safety of the FloWise were evaluated in the elastase-induced rabbit aneurysm model. The rate of technical success (full coverage of aneurysm neck) and assessment of aneurysm occlusion and stent patency was conducted by angiograms and histologic examinations at the 1-month, 3-month, and 6-month follow-up. The patency of small arterial branches (intercostal or lumbar arteries) covered by the FloWise were also assessed in the 5 subjects. RESULTS: We attempted FloWise insertion in a total of 32 aneurysm models. FloWise placement was successful in 31 subjects (96.9%). Two stents (6.2%) were occluded at the 3-month follow-up, but there was no evidence of in-stent stenosis in other subjects. All stented aneurysms showed progressive occlusion: grade I (complete aneurysm occlusion) in 44.4% and grade II (aneurysm occlusion > 90%) in 55.6% at 1 month; grade I in 90% and II in 10% at 3 months; and grade I in 90% and II in 10% at 6 months. All small arterial branches covered by the FloWise remained patent. CONCLUSION: A newly developed, partially retrievable flow-diverter seems to be a safe and effective tool of aneurysm occlusion, as evaluated in the rabbit aneurysm model.
Alloys
;
Aneurysm/*chemically induced/radiography/*surgery
;
Angiography
;
Animals
;
Arteries/pathology/surgery
;
Catheters
;
Cerebrovascular Circulation/physiology
;
Constriction, Pathologic/chemically induced/radiography/surgery
;
*Disease Models, Animal
;
Humans
;
Male
;
Pancreatic Elastase/*pharmacology
;
Platinum
;
*Rabbits
;
Stents/*adverse effects
9.The Impact of Hemodialysis and Arteriovenous Access Flow on Extracranial Hemodynamic Changes in End-Stage Renal Disease Patients.
Sarah CHUNG ; Hye Seon JEONG ; Dae Eun CHOI ; Hee Jung SONG ; Young Gi LIM ; Joo Yeon HAM ; Ki Ryang NA ; Kang Wook LEE
Journal of Korean Medical Science 2016;31(8):1239-1245
In this study, we characterized cerebral blood flow changes by assessment of blood flow parameters in neck arteries using carotid duplex ultrasonography and predictive factors for these hemodynamic changes. Hemodynamic variables were measured before and during hemodialysis in 81 patients with an arteriovenous access in their arm. Hemodialysis produced significant lowering in peak systolic velocity and flow volume of neck arteries and calculated total cerebral blood flow (1,221.9 ± 344.9 [before hemodialysis] vs. 1,085.8 ± 319.2 [during hemodialysis], P < 0.001). Effects were greater in vessels on the same side as the arteriovenous access and these changes were influenced by arteriovenous access flow during hemodialysis, both in the CCA (r = -0.277, P = 0.015) and the VA (r = -0.239, P = 0.034). The change of total cerebral blood flow during hemodialysis was independently related with age, presence of diabetes, and systemic blood pressure.
Aged
;
Carotid Arteries/diagnostic imaging
;
Cerebrovascular Circulation/*physiology
;
Dizziness/etiology
;
Female
;
Hemodynamics/*physiology
;
Humans
;
Kidney Failure, Chronic/*physiopathology
;
Male
;
Middle Aged
;
Renal Dialysis
;
Risk Factors
;
Ultrasonography, Doppler, Duplex
10.The Impact of Hemodialysis and Arteriovenous Access Flow on Extracranial Hemodynamic Changes in End-Stage Renal Disease Patients.
Sarah CHUNG ; Hye Seon JEONG ; Dae Eun CHOI ; Hee Jung SONG ; Young Gi LIM ; Joo Yeon HAM ; Ki Ryang NA ; Kang Wook LEE
Journal of Korean Medical Science 2016;31(8):1239-1245
In this study, we characterized cerebral blood flow changes by assessment of blood flow parameters in neck arteries using carotid duplex ultrasonography and predictive factors for these hemodynamic changes. Hemodynamic variables were measured before and during hemodialysis in 81 patients with an arteriovenous access in their arm. Hemodialysis produced significant lowering in peak systolic velocity and flow volume of neck arteries and calculated total cerebral blood flow (1,221.9 ± 344.9 [before hemodialysis] vs. 1,085.8 ± 319.2 [during hemodialysis], P < 0.001). Effects were greater in vessels on the same side as the arteriovenous access and these changes were influenced by arteriovenous access flow during hemodialysis, both in the CCA (r = -0.277, P = 0.015) and the VA (r = -0.239, P = 0.034). The change of total cerebral blood flow during hemodialysis was independently related with age, presence of diabetes, and systemic blood pressure.
Aged
;
Carotid Arteries/diagnostic imaging
;
Cerebrovascular Circulation/*physiology
;
Dizziness/etiology
;
Female
;
Hemodynamics/*physiology
;
Humans
;
Kidney Failure, Chronic/*physiopathology
;
Male
;
Middle Aged
;
Renal Dialysis
;
Risk Factors
;
Ultrasonography, Doppler, Duplex

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