• Korea-Australia Rheology Journal
• /
• v.17 no.3
• /
• pp.117-123
• /
• 2005

Background: Reduced deformability of red blood cells (RBCs) may play an important role on the pathogenesis of chronic vascular complications of diabetes mellitus. However, available techniques for measuring RBC deformability often require washing process after each measurement, which is not optimal for day­to-day clinical use at point of care. The objectives of the present study are to develop a device and to delineate the correlation of impaired RBC deformability with diabetic nephropathy. Methods: We developed a disposable ektacytometry to measure RBC deformability, which adopted a laser diffraction technique and slit rheometry. The essential features of this design are its simplicity (ease of operation and no moving parts) and a disposable element which is in contact with the blood sample. We studied adult diabetic patients divided into three groups according to diabetic complications. Group I comprised 57 diabetic patients with normal renal function. Group II comprised 26 diabetic patients with chronic renal failure (CRF). Group III consisted of 30 diabetic subjects with end-stage renal disease (ESRD) on hemo-dialysis. According to the renal function for the diabetic groups, matched non-diabetic groups were served as control. Results: We found substantially impaired red blood cell deformability in those with normal renal function (group I) compared to non-diabetic control (P = 0.0005). As renal function decreases, an increased impairment in RBC deformability was found. Diabetic patients with chronic renal failure (group II) when compared to non-diabetic controls (CRF) had an apparently greater impairment in RBC deformability (P = 0.07). The non-diabetic cohort (CRF), on the other hand, manifested significant impairment in red blood cell deformability compared to healthy: control (P = 0.0001). Conclusions: The newly developed slit ektacytometer can measure the RBC deformability with ease and accuracy. In addition, progressive impairment in cell deformability is associated with renal function loss in all patients regardless of the presence or absence of diabetes. In diabetic patients, early impairment in RBC deformability appears in patients with normal renal function.

• Journal of Trauma and Injury
• /
• v.26 no.3
• /
• pp.248-251
• /
• 2013

Introduction: A post-traumatic mesenteric arteriovenous fistula (AVF) is extremely rare. Case Report: A previously healthy 26-year-old male was injured with an abdominal stab wound. Computed tomography (CT) showed liver injury, pancreas injury and a retropancreatic hematoma. We performed the hemostasis of the bleeding due to the liver injury, a distal pancreatectomy with splenectomy and evacuation of the retropancreatic hematoma. On the 5th postoperative day, an abdominal bruit and thrill was detected. CT and angiography showed an AVF between the superior mesenteric artery (SMA) and the inferior mesenteric vein with early enhancement of the portal vein (PV). The point of the AVF was about 4 cm from the SMA's orifice. After an emergent laparotomy and inframesocolic approach, the isolation of the SMA was performed by dissection and ligation of adjacent mesenteric tissues which was about 6 cm length from the nearby SMA orifice, preserving the major side branches of the SMA, because the exact point of the AVF could not be identified despite the shunt flow in the PV being audible during an intraoperative hand-held Doppler-shift measurement. After that, the shunt flow could not be detected by using an intraoperative hand-held Doppler-shift measuring device. CT two and a half months later showed no AVF. There were no major complications during a 19-month follow-up period. Conclusion: Early management of a post-traumatic mesenteric AVF is essential to avoid complications such as hemorrhage, congestive heart failure and portal hypertension.

• The Journal of Internal Korean Medicine
• /
• v.20 no.1
• /
• pp.57-72
• /
• 1999

This study was designed to elucidate the anti-inflammatory, cardiovascular, anti-thrombotic, and analgesic effect of Whalrakdan. The anti-inflammatory effects was measured by the method of carrageenin induced edema, protein leakage test using CMC-pouch, and the effect of Whalrakdan on the cardiovascular system was observed by the change of flow rate of Ringer solution in the vascular system in the ear of rabbit. and the contraction and dilatation of rat tail artery. Death rate, platelet aggregation, plasma coagulation activity, antithrombin activity was observed for the measurement of the anti-thrombotic effect of Whalrakdan, and the analgesic effect was measured by the acetic acid method and hot plate method. The result was as follows: 1. After 2 or 3hour of Whalrakdan administration, carrageenin induced edema and CMC-pouch protein leakage was significantly decreased. 2. The slight anagesic effect of Whalrakdan extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time. 3. The droplet of Ringer solution increased according to the increase of concentration of Whalrakdan extract, and the vasoconstriction decreased dependantly to the concentration of Whalrakdan extract. 4. The anti-thrombotic effect of Whalrakdan was observed by the decrease of death rate, the inhibition of platelet aggregation, and the increase of anti-thrombin activity.

• Archives of Plastic Surgery
• /
• v.39 no.3
• /
• pp.227-231
• /
• 2012

Background : The ankle brachial pressure index (ABI) is a simple, useful method for diagnosing peripheral artery disease (PAD). Although the ABI is an objective diagnostic method, it has limited reliability in certain scenarios. The aim of the present study was to determine the accuracy and reliability of the toe brachial index (TBI) as a diagnostic tool for detecting stenosis in PAD, associated with normal or low ABI values. Methods : ABI and TBI values were measured in 15 patients with diabetic gangrene who were suspected of having lower extremity arterial insufficiency. The ABI and TBI values were measured using a device that allowed the simultaneous measurement of systolic blood pressure in the upper and lower extremities. In addition, the ABI and TBI values were compared pre- and post-angiography. Results : Patients with an ABI of 0.9-1.3 showed almost no difference between the 2 measurements. The patients with TBI >0.6 had no arterial insufficiency. The patients with TBI <0.6 required vascular intervention with ballooning. After the angiography, the gangrenous wounds decreased in size more rapidly than they did prior to the intervention. Conclusions : Our findings suggest that TBI is the method of choice for evaluating lower limb perfusion disorders. This result requires further studies of TBI in a larger number of patients. Future long-term studies should therefore evaluate the utility of TBI as a means of screening for PAD and the present findings should be regarded as preliminary outcomes.

• The Korean Journal of Nuclear Medicine
• /
• v.9 no.1
• /
• pp.21-29
• /
• 1975

Radioimmunoassay for the measurement of plasma renin activity (PRA) was performed in 43 normal Koreans and 45 patients with essential hypertension. Plasma samples were drawn in supine position in the morning and after upright posture for 4 hours. Urinary sodium excretion rates were measured in the concurrent 24 hour urine samples, as an index of their sodium balance. The results were as follows: 1. There was an inverse correlation between 24hr sodium excretion and PRA. The normal values of PRA in supine position ranged from 1.0 to 7.0 ng/ml/hr. when 24 hour sodium excretion were between 50 to 150 mEq. PRA in elderly tended to be low. 2. When stimulated by 4 hour upright posture, PRA increased by 2.6 times from the baseline value. 3. Of the 45 patients with essential hypertension, PRA was low in 10 cases (22.2%), normal in 28 cases (62.2%), and high in 7 cases (15.6%). 4. In the normal and high renin groups, who tended to be younger in ages, mean diastolic blood pressure and BUN were higher than in low renin group. Though hypertensive retinopathy and left ventricular hypertrophy in ECG were more prevalent in the former, no significant differences were noted as in the case of serum cholesterol. 5. There were 8 cases of cardiovascular complications (7 with cerebral vascular accident, 1 with myocardial infarction); 3 in low renin group (30%), 2 in normal renin (7.1%) and 3 in high renin group (42.9%). This figure indicated higher rate of cardiovascular complications in high renin groups, and lower rate in normal renin group. But the incidence of the complication was not significantly low in low renin group.

• Proceedings of the KAIS Fall Conference
• /
• 2009.05a
• /
• pp.236-239
• /
• 2009

본 연구는 40~50대 중년 남녀를 대상으로 신체계측을 통해 얻어진 신체계측치 및 혈관탄성도와 최대산소섭취량의 관련성을 규명하기 위하여 일개 군 보건소 운동처방실을 방문한 남자 43명, 여자 53명을 대상으로 신체계측치 및 혈관탄성도, 최대산소섭취량 등을 측정하였다.결과를 보면 1.남자의 신체계측치와 혈관탄성도의 상관관계에서는 비만도가, 여자에서는 허리-엉덩이비율이 유의한 상관관계를 보였다. 2.남자의 신체계측치와 최대산소섭취량의 상관관계에서는 비만도, 체질량지수, 허리-엉덩이비율, 체지방율이 유의한 상관관계를 보였으며, 여자에서는 허리-엉덩이 비율, 체지방율이 유의한 상관관계를 보였다. 3.남자의 혈관탄성도 및 심혈관계지표와 최대산소섭취량의 상관관계에서는 최대심박수가 유의한 상관관계를 보였고, 여자에서는 혈관탄성도, 최대심박수가 유의한 상관관계를 보였다. 최대 산소섭취량을 종속변수로 한 다중회귀분석에서는 남녀 모두 체지방율, 혈관탄성도, 최대심박수가 유의한 변수로 나타났다. 즉 체지방율이 낮을수록, 혈관탄성도가 높을수록, 최대심박수가 높을수록 최대 산소섭취량이 높았다. 따라서 40~50대 중년의 최대산소섭취량에 영향을 주는 요인에는 신체계측에 의한 비만관련지수, 혈관탄성도, 심혈관계지표 등 여러 요인들이 복합적으로 관련되는 것으로 판단되어진다.

• Macromolecular Research
• /
• v.17 no.7
• /
• pp.458-463
• /
• 2009

Polyurethane (PU) is widely used as a cardiovascular biomaterial due to its good mechanical properties and hemocompatibility, but it is not adhesive to endothelial cells (ECs). Cell adhesive peptides, GRGDS and YIGSR, were found to promote adhesion and spreading of ECs and showed a synergistic effect when both of them were used. In this study, a surface modification was designed to fabricate an EC-active PU surface capable of promoting endothelialization using the peptides and poly(ethylene glycol) (PEG) spacer, The modified PU surfaces were characterized in vitro. The density of the grafted PEG on the PU surface was measured by acid-base back titration to the terminal-free isocyanate groups. The successful immobilization of pep tides was confirmed by amino acid analysis, following hydrolysis, and contact angle measurement. The uniform distribution of peptides on the surface was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). To evaluate the EC adhesive property, cell viability test using human umbilical vein EC (HUVEC) was investigated in vitro and enhanced endothelialization was characterized by the introduction of cell adhesive peptides, GRGDS and YIGSR, and PEG spacer. Therefore, GRGDS and YIGSR co-immobilized PU surfaces can be applied to an EC-specific vascular graft with long-term patency by endothelialization.

• Environmental Analysis Health and Toxicology
• /
• v.21 no.1 s.52
• /
• pp.71-79
• /
• 2006

Epidemiologic studies have showed a close correlation between arsenic exposure and heart disease such as, cardiovascular problem, ischemic heart disease, infarction, atherosclerosis and hypertension in human. It may increase the mortality of high risk group with heart disease. Regarding the mechanism studies of heart failure, blood vessel, vascular smooth muscle cells and endothelial cells have long been focused as the primary targets in arsenic exposure but there are only a few studies on the cardiomyocytes. In this study, the generation of oxidative stress by low dose of arsenic trioxide was investigated in rat cardiomyocytes. By direct measurement of reactive oxygen species and fluorescent microscopic observation using fluorescent dye 2',7'-dichlorofluorescin diacetate, reactive oxygen species were found to be generated without cell death, where cells are treated with 0.1 ppm arsenic for 24 hours. With the induction of reactive oxygen species, GSH level was decreased by the same treatment. However, DNA damage did not seem to be serious by DAPI staining, while high dose of arsenic (2 ppm for 24 hrs) caused fragmentation of DNA. To identify the molecular biomarkers of low-dose arsenic exposure, gene expression was also investigated with whole genome microarray. As results, 9,022 genes were up-regulated including heme oxygenase-l and glutathione S-transrerase, which are well-known biomarkers of oxidative stress. 9,404 genes were down-regulated including endothelial type gp 91-phox gene by the treatment of 0.1 ppm arsenic for 24 hours. This means that biological responses of cardiomyocytes may be altered by ROS induced by low level arsenic without cell death, and this alteration may be detected clearly by molecular biomarkers such as heme oxygenase-1.

• The Korean Journal of Physiology and Pharmacology
• /
• v.5 no.1
• /
• pp.1-8
• /
• 2001

Hyperpolarization of arterial smooth muscle by acetylcholine is considered to be produced by the release of an unidentified chemical substance, an endothelium-derived hyperpolarizing factor (EDHF). Several chemicals have been proposed as the candidate for EDHF. However, none of them fulfil completely the nature and property of EDHF. Ultrastructural observation with electron microscope reveals that in some arteries, gap junctions are formed between endothelial and smooth muscle cells. In small arterioles, injection of gap junction permeable dyes into an endothelial cell results in a distribution of the dye to surrounding cells including smooth muscle cells. These observations allow the speculation that myoendothelial gap junctions may have a functional significance. Simultaneous measurement of the electrical responses in both endothelial and smooth muscle cells using the double patch clamp method demonstrates that these two cell types are indeed electrically coupled, indicating that they behave as a functional syncytium. The EDHF-induced hyperpolarization is produced by an activation of $Ca^{2+}-sensitive\;K^+-channels$ that are inhibited by charybdotoxin and apamin. Agonists that release EDHF increase $[Ca^{2+}]_i$ in endothelial cells but not in smooth muscle cells. Inhibition of gap junctions with chemical agents abolishes the agonist-induced hyperpolarization in smooth muscle cells but not in endothelial cells. All these observations can be explained if EDHF is an electrotonic signal propagating from endothelium to smooth muscle cells through gap junctions.

• Parasites, Hosts and Diseases
• /
• v.58 no.4
• /
• pp.461-466
• /
• 2020

Toxoplasma gondii is an obligate intracellular protozoan parasite that can invade various organs in the host body, including the central nervous system. Chronic intracranial T. gondii is known to be associated with neuroprotection against neurodegenerative diseases through interaction with host brain cells in various ways. The present study investigated the neuroprotective effects of chronic T. gondii infection in mice with cerebral ischemia experimentally produced by middle cerebral artery occlusion (MCAO) surgery. The neurobehavioral effects of cerebral ischemia were assessed by measurement of Garcia score and Rotarod behavior tests. The volume of brain ischemia was measured by triphenyltetrazolium chloride staining. The expression levels of related genes and proteins were determined. After cerebral ischemia, corrected infarction volume was significantly reduced in T. gondii infected mice, and their neurobehavioral function was significantly better than that of the uninfection control group. Chronic T. gondii infection induced the expression of hypoxia-inducible factor 1-alpha (HIF-1α) in the brain before MCAO. T. gondii infection also increased the expression of vascular endothelial growth factor after the cerebral ischemia. It is suggested that chronic intracerebral infection of T. gondii may be a potential preconditioning strategy to reduce neural deficits associated with cerebral ischemia and induce brain ischemic tolerance through the regulation of HIF-1α expression.