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The objective of this study was to compare aortic (the common carotid to femoral artery) PWV, arm (the brachial to radial artery) PWV, and leg (the femoral to dorsalis pedis artery) PWV in people with or without component of the metabolic syndrome. We analyzed 3345 Korean subjects (1907 men, age 44.6 ± 8.5, 1438 women, age 43.3 ± 8.9). Unpaired t-test was used to compare mean values of various metabolic parameters between subjects with and without Metabolic Syndrome (MetS), and one-way analysis of variance was used to compare these variables among groups satisfying different numbers of the components of MetS. In addition, we compared of Pearson correlation coefficient between age and PWV (arotic PWV, arm PWV and leg PWV) levels of according to whether the subject had components of the metabolic syndrome or not. The present study shows that leg PWV level was found to be significantly associated with the features of the metabolic syndrome in Korean men and women. And, we confirmed that blood pressure is significantly associated with the PWV values at three locations. And, this study shows that Pearson correlation coefficient of arotic PWV and leg PWV were about 10% higher than without diabetes according to age. Further studies need to be performed to evaluate the optimal cut-off value of PWV for diabetes, hypertension, and MetS in Korean. [ABSTRACT FROM AUTHOR]

In 2002, the paracorporeal pulsatile electro-mechanical pneumatic ventricular assist device (VAD) began to be developed by the Korea Artificial Organ Center at Korea University under a Health & Medical Technology Research and Development program which finished in 2008. In vitro durability testing was conducted on the paracorporeal pulsatile pneumatic VAD to determine device durability and to evaluate device failures. The 1- and 2-year reliability of the paracorporeal pulsatile pneumatic VAD was shown to be 91.2% and 54.9%, respectively, with an 80% confidence level. Failure modes were analyzed using fault tree analysis, with customized software continuously acquiring data during the test period. After this period, 21 in vivo animal tests were done, with 14 cases of left atrium to left ventricle (LV) inflow cannulation (36Fr)/outflow grafting to descending aorta, and seven cases of apex cannulation of LV to descending aorta (12 mm). The longest postoperative day (182 days) in Korea was recently recorded in in vivo animal testing (bovine, 90 kg, male, 3.5-4.0 L/min flow rate, and 55 bpm)., (© 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

With the increase in demand for high quality medical services, the need for an innovative hospital information system has become essential. An improved system has been implemented in all hospital units of the Yonsei University Health System. Interoperability between multi-units required appropriate hardware infrastructure and software architecture. This large-scale hospital information system encompassed PACS (Picture Archiving and Communications Systems), EMR (Electronic Medical Records) and ERP (Enterprise Resource Planning). It involved two tertiary hospitals and 50 community hospitals. The monthly data production rate by the integrated hospital information system is about 1.8 TByte and the total quantity of data produced so far is about 60 TByte. Large scale information exchange and sharing will be particularly useful for telemedicine applications.

Multispecialist teleconsultation systems can be particularly useful in obtaining a second opinion from remote medical specialists. In this paper, a multispecialist teleconsultation (MST) system was designed by using multiple unicasting to enable operability over the existing Internet infrastructure and the support of reliable data transmission. The MST was tested over Asynchronous Digital Subscriber Line (ADSL), Very high speed Digital Subscriber Line (VDSL), Wireless Local Area Network (WLAN), and the hospital Local Area Network (LAN) to demonstrate the operability of the designed system over popularly deployed networks that together make up the current Internet. Also, subjective evaluation using induced delay and low quality video coding of sample brain surgery testing videos and two cases of clinical experimentations demonstrated the limiting factors of the MST in terms of quality and delay differences as well as the feasibility of the MST in a real clinical setting.

To investigate the association between Korean red ginseng (KRG) intake in HIV-1 infected patients and the occurrence of grossly deleted nef genes (gDeltanef), we characterized nef genes in 10 long-term slow progressors (LTSP) infected with HIV-1 subtype B and 34 control patients. LTSP was defined by the annual decrease in CD4 T cells being less than 20/microl over 10 years in the absence of antiretroviral therapy. They were treated with KRG for a prolonged period. Nef genes were amplified from peripheral blood mononuclear cells (PBMC) using nested PCR and the products were sequenced directly. It was observed that the patients CD4 T cell counts decreased from 444 +/- 207/microl to 294 +/- 177/microl over 136 +/- 23 months of KRG intake. This corresponds to an annual decrease in the level of CD4 T cells of 13.3/microl. A total of 479 nef genes were amplified from 137 PBMC samples. Nine out of the 10 patients, 47 (34.3%) out of the 137 samples, and 90 out of the 479 genes revealed gDeltanef. The deletion extended outside the nef gene in 25 gDeltanef obtained from 6 patients. The proportion of samples with gDeltanef (34.3%) was significantly higher than 4.8% in control patients (P < 0.001). In addition, it significantly increased as the duration of KRG intake prolongs (P < 0.01). These data suggest that the occurrence of gDeltanef might be associated with long-term intake of KRG.

The Twin-Pulse Life Support System (T-PLS) is a novel pulsatile extracorporeal life support system developed in Korea. It has been reported that the T-PLS achieves higher levels of tissue perfusion of the kidney during short-term extracorporeal circulation and provides more blood flow to coronary artery than nonpulsatile blood pumps. However, these results lack pulsatility quantifications and thus make it hard to analyze the effects of pulsatility upon hemodynamic performance. We have adopted the concepts of hemodynamic energy, energy equivalent pressure (EEP), and surplus hemodynamic energy (SHE) to evaluate pulsatility performance in the different circuit configurations of the T-PLS and a membrane oxygenator (MO) in vitro. In a mock system, three different circuits were constructed depending on the location of an MO: pump-MO-pump (serial), MO-pumps (parallel A), and pumps-MO (parallel B). In parallel A, a low-resistance MO was used to preserve the pulsatility from the pump. All circuits showed good pulsatility in terms of EEP (serial: 13.2% +/- 3.2%, parallel A: 10.0% +/- 1.6%, parallel B: 7.00% +/- 1.1%; change from aortic pressure to EEP; p < 0.003). The SHE levels were 17,404 +/- 3750 ergs/cm3, 13,170 +/- 1486 ergs/cm3, and 9192 +/- 1122 ergs/cm3 in each circuit setup (p < 0.001). Although EEP levels were somewhat lower, both parallel types provided higher pump output compared with the serial type (serial: 1.87 +/- 0.29 l/min, parallel A: 3.09 +/- 0.74 l/min, parallel B: 3.06 +/- 0.56 l/min; p < 0.003 except parallel A vs. parallel B, p = 0.90). Conclusively, the precise quantifications of pressure flow waveforms, EEP, and SHE are valuable tools for evaluating pulsatility of the mechanical circulatory devices, and are expected to be used as additional performance indexes of a blood pump. The pulsatility performances are different according to circuit setups. However, the parallel A circuit could achieve higher pump output and generate adequate pulsatility level. Thus, the parallel A circuit is suggested as the optimal configuration in T-PLS applications.

Background: The commercially available formulation of amlodipine is conjugated with besylate salt to increase water solubility. Recently, a new amlodipine salt formulation has been developed in which the free base of amlodipine is conjugated with a chemically different salt, adipate., Objective: The goal of this study was to compare the antihypertensive effect and tolerability of amlodipine adipate with those of amlodipine besylate in patients with mild to moderate hypertension., Methods: This was a multicenter, randomized, doubleblind, parallel-group study in which patients received 8 weeks of treatment with either amlodipine adipate or amlodipine besylate. The primary efficacy variable was noninferiority of the difference in mean changes from baseline in trough diastolic blood pressure (DBP) after 8 weeks of treatment. Secondary efficacy variables included mean changes in DBP, systolic blood pressure (SBP), and response rate (defined as the proportion of patients whose DBP was <90 mm Hg or whose DBP had decreased from baseline by > or =10 mm Hg). The incidence of adverse events (AEs) was also assessed., Results: Two hundred eleven patients were randomly assigned to receive amlodipine adipate (n = 106) or amlodipine besylate (n = 105). Study patients were primarily female (54.5%), with a mean (SD) age of 52.2 (9.6) years and a mean body weight of 67.1 (10.2) kg; there were no between-group differences in demographic profiles. After 4 weeks of randomized treatment, 58 (27.5%) patients (29 [27.4%] amlodipine adipate, 29 [27.6%] amlodipine besylate) had not achieved a mean DBP <90 mm Hg, and their dose was doubled. Mean DBP changes at 8 weeks were -15.2 (7.3) mm Hg in the amlodipine adipate group and -14.2 (7.4) mm Hg in the amlodipine besylate group (P = NS). Because the 95% CI for the difference in mean DBP changes between groups (-0.53 to 2.55) was within the prespecified lower limit (-4 mm Hg), amlodipine adipate was considered noninferior to amlodipine besylate. Mean SBP changes were -24.9 (12.1) mm Hg in the amlodipine adipate group and -22.0 (14.7) mm Hg in the amlodipine besylate group (P = NS). The response rates were 92.0% for amlodipine adipate and 95.4% for amlodipine besylate (P = NS). The overall incidence of clinical AEs was 20.8% in the amlodipine adipate group and 25.7% in the amlodipine besylate group (P = NS). Drug-related clinical AEs occurred in 5.7% and 12.4% of patients in the respective treatment groups (P = NS). Serum uric acid levels decreased significantly from base-line in both groups (P < 0.001)., Conclusions: Eight weeks of treatment with amlodipine adipate produced significant reductions from baseline in blood pressure in these patients with mild to moderate hypertension. The efficacy of amlodipine adipate was not inferior to that of amlodipine besylate. Tolerability was comparable between the 2 treatment groups.

Flow in the blood sac of the Korean artificial heart is numerically simulated by finite element method. Fluid-structure interaction algorithm is employed to compute the three-dimensional blood flow interacting with the sac material. For verification of the numerical method of fluid-structure interaction, two-dimensional flow in a collapsible channel with initial tension is simulated and the results are compared with numerical solutions from the literature. Incompressible viscous flow and linear elastic solid are assumed for the blood and the sac material in the device, respectively. The motion of the actuator is simplified by a time-varying pressure boundary condition imposed on the outer surface of the sac. Numerical solutions on the unsteady three-dimensional blood flow in the sac are provided for the cactus-type model in this study. During systole, the inlet is closed and the blood sac is squeezed by the action of the prescribed pressure on the surface. During diastole, the sac is filled with the blood coming from the inlet while the outlet is closed. A strong flow to the outlet and a stagnated flow near the inlet are observed during systole. Shear stress distribution is also delineated to assess the possibility of thrombus formation. We also simulate numerically the hemodynamics of "the reversed model" where the inlet and outlet are reversed for surgical convenience. It is observed that a recirculating flow was generated near the inner corner of the sac in the reversed model. To assess the material strength of the sac, the shear stress distribution in the solid material is also presented.

A Korean artificial heart (AnyHeart) has been implanted in 29 various animals (52-470 kg) to evaluate hemodynamic performance and electromechanical stability. Most were implantable biventricular assist devices in use. A right thoracotomy approach has been a standard technique of implantation. A preclinical fitting test was also performed to observe anatomical feasibility and to compare surgical techniques in 10 human cadavers. The first case of human application was made as a lifesaving procedure on June 12, 2001.