No abstract available.
Blood Viscosity* ; Hydroxymethylglutaryl-CoA Reductase Inhibitors*

BACKGROUND: Normal erythrocyte is deformable and this facilitates blood flow in the capillaries. Oxidative stress reduces the deformability of erythrocytes, and influences on blood flow in microcirculation. The objective of this study was to investigate the deformability of erythrocytes exposed to oxidative stress, the protective effects of verapamil and ascorbic acid against oxidative damages in erythrocytes, and the value of the microfluidic ektacytometer, RheoScan-D (RheoMeditech, Korea) in clinical application. METHODS: Effects of oxidative stress on erythrocytes were investigated using tert-butyl hydroperoxide (tBHP). Before exposure to tBHP, the erythrocytes were pretreated with verapamil and ascorbic acid to examine their protective effect against oxidative damages. The deformability of erythrocytes was measured by the microfluidic ektacytometer, RheoScan-D. RESULTS: When treated with tBHP, the deformability of erythrocytes was decreased (P<0.01) and methemoglobin (metHb) formation and mean corpuscular volume (MCV) of erythrocytes were increased (P<0.01, P<0.05) compared to those of the untreated control cells. Compared to the tBHP treated cells, pretreatment with verapamil increased the deformability of erythrocytes (P<0.01) and decreased metHb formation (P<0.01) and MCV (P<0.05). Likewise, pretreatment with ascorbic acid increased the deformability of erythrocytes (P<0.01) and decreased metHb formation (P<0.01). CONCLUSIONS: Oxidative stress reduces the deformability of erythrocytes and the deformability could be one of markers for oxidative damage. Verapamil and ascorbic acid have protective role against tBHP induced oxidative stress. The ektacytometer, RheoScan-D used in this study is convenient for clinical measurement and could be used in various fields of clinical medicine.
Adult ; Antioxidants/pharmacology ; Ascorbic Acid/*pharmacology ; Calcium Channel Blockers/pharmacology ; Erythrocyte Deformability/*drug effects ; Erythrocytes/drug effects/physiology ; Humans ; Male ; Microfluidic Analytical Techniques/*instrumentation ; Oxidative Stress ; Statistics, Nonparametric ; Verapamil/*pharmacology ; tert-Butylhydroperoxide/*pharmacology

BACKGROUND: The red blood cell (RBC) deformability test is a useful method for measuring the ability of RBCs to adapt their shape to the flow conditions. Using this test, several investigators have shown the relationship between RBC deformability and numerous clinical conditions. For the quality control (QC) of RBC deformability test, we evaluated whether frozen-thawed-deglycerolized RBCs can be used as QC materials. METHODS: Packed RBCs were frozen with 40% (wt/vol) glycerol and stored at -80degrees C for 3 months. For 10 different frozen RBC panels, RBCs were thawed, deglycerolized and stored at 4degrees C for 4 weeks. Using microfluidic ektacytometer, we measured RBC deformability of the thawed RBCs. The stability of thawed RBCs was tested once a day for 28 days of storage time and was analyzed by simple regression analysis. The precision of the test using thawed RBCs was analyzed for 7 days of storage time by calculation of CV values of intra-assay (10 measurements/assay) and between-day measurements. RESULTS: Frozen-thawed-deglycerolized RBCs were stable for 1 week. Within-run and between-day precisions of the RBC deformability test during 7 days of storage of thawed RBCs were 1.4-2.9%, and 1.9-2.8%, respectively. CONCLUSIONS: Frozen-thawed-deglycerolized RBCs used in RBC deformability test showed satisfactory within-run and between-run precisions and stability for one week after thawing, and may be used as QC materials for this test.
Blood Preservation ; Cryopreservation ; Cryoprotective Agents/chemistry/isolation & purification ; *Erythrocyte Deformability ; Erythrocytes/immunology/physiology ; Glycerol/chemistry/isolation & purification ; Hematologic Tests/standards ; Humans ; Quality Control

OBJECTIVE: This study is to determine the cross-cultural adaptation and validation of the Korean version of the EQ-5D (KEQ-5D) in various rheumatic patients. METHODS: We performed translation, backward translation and cognitive debriefing by the guidelines of the EuroQol group. The validity was evaluated by using the KEQ-5D, Korean Short- Form 36 (KSF-36) and disease-specific measures on 508 out-patients with ankylosing spondylitis, fibromyalgia syndrome, rheumatoid arthritis, osteoarthritis or systemic lupus erythematosus. Construct validity were evaluated by testing a-priori hypotheses of the association between the KEQ-5D and other measures. For the verification of reliability, we gave the same questionnaires twice to another 57 patients 1-week apart, and intra-class correlations and Kappa statistics were estimated. To test responsiveness, 60 patients with RA repeated the KEQ-5D at 12-week intervals within the context of 12-week clinical trials of a TNF blocker, and we calculated the t-test, effect size and standardized response mean RESULTS: There were no major modifications on the cross-cultural adaptation. The relationships between the KEQ-5D and the generic or disease-specific measures were observed to be as we expected previously in a-priori hypotheses:higher KEQ-5Dindex and KEQ-5DVAS scores were correlated with generic or disease-specific measures on the better health status, and groups with a better functional class showed higher KEQ-5D scores. The intra-class correlations of the KEQ-5Dindex and KEQ-5DVAS were 0.751 and 0.767, respectively, and Kappa statistics for agreement ranged from 0.455 to 0.772 across five dimensions. The standardized response means of KEQ-5Dindex and KEQ-5DVAS were 0.649 and 0.410. CONCLUSION: The KEQ-5D had good validity and sensitivity in several rheumatic conditions. Also, its reliability and responsiveness were moderate to good.
Arthritis, Rheumatoid ; Fibromyalgia ; Humans ; Korea ; Lupus Erythematosus, Systemic ; Osteoarthritis ; Outpatients ; Quality of Life ; Surveys and Questionnaires ; Rheumatic Diseases* ; Spondylitis, Ankylosing

PURPOSE: To investigate the frequency of significant intraocular sequelae (SIOS) in orbital blunt trauma and their association with blowout and facial bone fractures. METHODS: A retrospective survey consisting of 726 patients with orbital blunt trauma who visited Korea University Medical Center was performed. Patients were divided into three groups: blowout fracture only group (group 1), facial bone fracture group (nasal bone fracture, maxillary fracture, zygoma fracture without blowout fracture, group 2), and non-fracture group (group 3). SIOS (traumatic iridocyclitis, commotio retina, hyphema, retinal hemorrhage, eyeball rupture, vitreous hemorrhage, retinal detachment, lens dislocation, traumatic cataract) were surveyed in each group, and the association between the frequency of SIOS and the presence of blowout fracture or facial bone fracture was analyzed. RESULTS: The frequency of SIOS in the fracture groups was 83.8% in group 1 and 73.3% in group 2, which were both higher than the 67.9% in group 3, the non-fracture group (p = 0.000 by chi-square linear by linear association). Traumatic iridocyclitis and hyphema were also significantly higher in groups 1 and 2 than group 3 (p = 0.003, p = 0.008 by chi-square linear by linear association). CONCLUSIONS: SIOS was found significantly more often in the fracture group than the group without fracture, although the frequency of severe SIOS was lower in the fracture group than the non-fracture group. The results from the present study could help in the treatment and management of patients with orbital blunt trauma.
Academic Medical Centers ; Facial Bones ; Fractures, Bone ; Humans ; Hyphema ; Iridocyclitis ; Korea ; Lens Subluxation ; Maxillary Fractures ; Orbit ; Retina ; Retinal Detachment ; Retinal Hemorrhage ; Retrospective Studies ; Rupture ; Vitreous Hemorrhage ; Zygoma

BACKGROUND: Irradiation of cellular blood products is the current method used for the prevention of transfusion-associated graft-versus-host disease. However, irradiation has been shown to cause biochemical changes in stored red blood cells (RBCs) and to generate reactive oxygen species (ROS). Irradiation-induced biochemical changes and oxidation damage of the RBCs is closely related to the deformability of these cells. Furthermore, deformation of the RBCs may lead to alterations in the post-transfusion viability of stored RBCs. In this study, we evaluated the physical properties of irradiated RBCs. METHODS: Citrate phosphate dextrose adenine-1 preserved RBC concentrates were irradiated with a minimum dose of 25 Gy and stored at 4oC for 28 days. The deformation of the RBCs was measured by a microfluidic ektacytometer (RheoScan-D). To examine the effect of oxidative stress, the RBC concentrates were exposed to oxidative stress using FeSO4 and ascorbic acid. RESULTS: The deformability threshold of the irradiated RBCs was significantly lower than that of the control RBCs on day 21 of storage and later (P<0.05). The deformability threshold of the RBCs exposed to oxidative stress was lower than that of control RBCs, and the difference was significant on day 21 of storage and later (P<0.05). For up to 21 days of storage, the deformability of control and irradiated RBCs were maintained; however, they were significantly decreased at 28 days of storage compared with 1 day of storage (P<0.05). CONCLUSION: Irradiation reduced the threshold of RBC deformability during storage. In accordance with the effect of irradiation, oxidative stress affected the RBC deformability. Therefore, a ROS scavenger may play a protective role against deformation of irradiated RBC concentrates. Further evaluation will be required for confirmation and clarification of these findings.
Ascorbic Acid ; Citric Acid ; Erythrocytes* ; Glucose ; Graft vs Host Disease ; Microfluidics ; Oxidative Stress ; Reactive Oxygen Species

Purpose: The purpose of this study is to understand the actual status of fundamentals of nursing practice (FNP) education at nursing colleges, and the difficulties of FNP operation in the early stages of the COVID-19. Methods: This study used a descriptive design. Data collection was conducted from December 9, 2020 to January 31, 2021 using the self-report questionnaire method for a total of 95 nursing colleges. The questionnaire consisted of characteristics related to FNP, changes in FNP education, difficulties in operating FNP, and countermeasures in the COVID-19 situation. Results: Changes in FNP due to COVID-19 were distribution of practice places, reduction of the number of students, short-term intensive classes, and reduction of face-to-face practice. Most colleges conducted FNP face-to-face, but some schools showed that FNP was conducted non-face-to-face. The difficulties of operating FNP that instructors experienced induced concerns about a decrease in student competency due to lack of face-to-face practice and an unofficial increase in the number of teaching hours and physical demands on instructors due to the expansion of the division. Conclusion In order to develop the capabilities of nursing students in other pandemic situations in the future, it is necessary to find systematic coping strategy to reduce the burden of FNP instructors, and to develop non-face-to-face online practice contents and consumables for online practice.