• Proceedings of the KACD Conference
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• 2003.11a
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• pp.546.1-546
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• 2003

Laser doppler flowmeter (LDF) has been applied to the measurement of pulpal blood flow (PBF) in human teeth. As far as we searched, the detection area of the pulp in the blood flow measurement has not been clarified, yet. Therefore, the purpose of this study was to obtain information of the detection area in PBF measurement using LDF. The experiments were performed on the artificial blood circulation in extracted human upper central incisors. The apical portions of examined teeth (n=6) were severed and root canals were enlarged from the apical end to the 2mm incisal to the level of enamel-cement junction. An individual resin cap of each tooth was prepared and a hole was drilled 2mm incisal to enamel-cement junction of the labial side of the cap. The measurement probe of LDF (MBF3D, Moor Instrument, UK) was plugged into the hole of the cap. Heparinized human peripheral blood, which was in advance collected and diluted 3 times with physiological saline, was pumped through the apical foramen of the teeth via a silicone tube and a disposable needle (o.d. 0.7mm) and blood flow signals were monitored. The flux signal significantly increased with the enlargement of the root canal to incisal direction (p<0.01, Friedman analysis). The result indicates that the performance of LDF in PBF with human teeth is limited.

• Advances in Traditional Medicine
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• v.3 no.1
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• pp.18-20
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• 2003

The purpose of this study was to examine the effect of supplementary highly purified chitosan (HPC) on blood alcohol concentration in healthy human. The human study was performed with two sections. Each section of the study was conducted by two-phase cross-over design with a week wash-out period. All volunteers took HPC in one phase, and took a placebo in the next phase. Blood alcohol concentrations were different between in those taking HPC and in those taking the placebo in the human. And the concentration of serum aspartate aminotransferase (AST, GOT) and alanine aminotransferase (ALT, GPT), the indicator of liver cell damage, was lowered in those taking HPC, compared to those taking the placebo. In conclusion, taking HPC prior to drinking alcohol can somewhat reduce alcohol concentration in human blood and liver cell damage.

• Journal of Korean Neurosurgical Society
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• v.30 no.8
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• pp.963-969
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• 2001

Objectives : Cord blood stem cells have been widely used as donor cells for bone marrow transplantation recently. These cells can give rise to a variety of hematopoietic lineages to repopulate the blood. Recent observations reveal that some bone marrow cells and bone marrow stromal cells(MSCs) can grow to become either neurons or glial cells. It is, however, unclear whether or not there exists stems cells which can differentiate into neurons in the blood during the early stages of postnatal life. Methods : Human cord blood stem cells were prepared from human placenta after full term delivery. To induce neuronal differentiation of stem cells, ${\beta}$-mercaptoethanol was treated. To confirm the neuro-glial characteristics of differentiated stem cells, immunocytochemical stain for NeuN, neurofilament, glial fibrillary acidic protein(GFAP), microtubule associated protein2(MAP2) was performed. RT-PCR was performed for detecting nestin mRNA and MAP2 mRNA. Results : We showed in this experiment that neuro-glial markers(NeuN, neurofilament, MAP2, GFAP) were expressed and axon-like cytoplasmic processes are elaborated in the cultured human cord blood stem cells prepared from new born placenta after full term delivery. Nestin mRNA was also detected in fresh cord blood monocytes. Conclusions : These results suggest that human cord blood derived stem cells may be potential sources of neurons in early postnatal life.

• Journal of Mechanical Science and Technology
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• v.17 no.7
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• pp.1016-1025
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• 2003

The rupture of blood vessels in the human brain results in serious pathological and medical problems. In particular, brain hemorrhage and hematomas resulting from impact to the head are a major cause of death. As such, investigating the tensile behavior and rupture of blood vessels in the brain is very important from a medical point of view. In the present study, the tensile characteristics of the blood vessels in the human brain were analyzed using a quasi-static uniaxial tensile test, and the properties of the arteries and veins compared. In addition, to compare the tensile behavior and demonstrate the validity of the experimental results, blood vessels from the legs of pigs were also tested and analyzed. The overall results were in accordance with the histological structures and previous medical reports.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.8
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• pp.777-782
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• 2007

Human Robot Interaction(HRI) through a haptic interface plays an important role in controlling robot systems remotely. The augmented usage of bio-signals in the haptic interface is an emerging research area. To consider operator's state in HRI, we used bio-signals such as ECG and blood pressure in our proposed force reflection interface. The variation of operator's state is checked from the information processing of bio-signals. The statistical standard variation in the R-R intervals and blood pressure were used to adaptively adjust force reflection which is generated from environmental condition. To change the pattern of force reflection according to the state of the human operator is our main idea. A set of experiments show the promising results on our concepts of human adaptive interface.

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.146-147
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• 2001

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1681-1685
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• 2012

A sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to determine valproic acid in human red blood cell (RBC). It is important to measure the drug concentration of the RBC as well as that of the plasma because of drug partitioning for pharmacokinetic and pharmacodynamic study. The method was linear over the dynamic range of 1-100 ${\mu}g$/mL with a correlation coefficient $r$ = 0.9997. The linearity of this method was established from 1 to 100 ${\mu}g$/mL for valproic acid in red blood cell with accuracy and precision within 15% at all concentrations. The intra-run and inter-run assay accuracy and coefficient of variations are all within 15% for all QC samples prepared in plasma and red blood human samples. Then, valproic acid amount by protein precipitation in plasma was quantified by LC-MS/MS mass spectrometry. The distribution ratio of VPA in RBC and plasma was analyzed by clinical samples. Based on measurement of the valproic acid in human red blood cell, this method has been applied to clinical research for study of distribution ratio of valproic acid in blood.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.285-290
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• 2008

Effects of titanium dioxide nanoparticles on blood coagulation and platelet aggregation were investigated using diluted whole blood and platelet rich plasma (PRP) solution prepared from human and rat blood, respectively. Blood coagulation was monitored by using a whole blood impedance aggregometer and titanium dioxide nanoparticle (10, 20, and 40 ppm) did not show any effect on the coagulation both in human and in rat blood. When platelet aggregation was measured by turbidometric method after addition of titanium dioxide nanoparticles to PRP solution with final concentrations of 1, 5 and 10 ppm. no aggregation was observed.

• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.42.1-42.11
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• 2022

Objective: This study investigated the effects of various concentrations of sodium hypochlorite (NaOCl) on human whole-blood clotting kinetics, the structure of the blood clots formed, and transforming growth factor (TGF)-β1 release. Materials and Methods: Human whole blood was collected from 5 healthy volunteers and divided into 4 groups: CG (control, 0.5 mL of blood), BN_0.5 (0.5 mL of blood with 0.5 mL of 0.5% NaOCl), BN₃ (0.5 mL of blood with 0.5 mL of 3% NaOCl), and BN_5.25 (0.5 mL of blood with 0.5 mL of 5.25% NaOCl). The effects of NaOCl on clotting kinetics, structure of fibrin and cells, and release of TGF-β1 were assessed using thromboelastography (TEG), scanning electron microscopy (SEM), and enzyme-linked immunosobent assay, respectively. Statistical analysis was conducted using the Kruskal Wallis and Mann-Whitney U tests, followed by the post hoc Dunn test. A p value < 0.05 indicated statistical significance. Results: The blood samples in BN_0.5 and BN₃ did not clot, whereas the TEG of BN_5.25 showed altered clot formation. Samples from the CG and BN₃ groups could only be processed with SEM, which showed that the latter lacked fibrin formation and branching of fibers, as well as clumping of red blood cells with surface roughening and distortion. TGF-β1 release was significantly highest in BN₃ when all groups were compared to CG (p < 0.05). Conclusions: Each concentration of NaOCl affected the release of TGF-β1 from blood clots and altered the clotting mechanism of blood by affecting clotting kinetics and cell structure.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.75-82
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• 1982

Normal range of mercury contents in blood and its relationship with urinary mercury excretion were studies with 68 healthy male adults living in Seoul city, who had no obvious evidence of .either occupational exposure to mercury or therapeutic use of mercurial agents. Mercury analysis was made by means of dithizone colorimetric method with coefficient of variation of 10.9% in .an average ranging from 5.1% to 18.0%. 1. Mercury contents in normal human blood were both normally and log-normally distributed, and better fitted to the latter. 2. Geometric mean and standard deviation of the mercury contents were $24.0(log^{-1}1.38){\pm}1.66{\mu}g/100ml(log^{-1}0.22{\mu}g/100ml)$ ranging from 7.2 to 79.7 ${\mu}g/100ml$ with 95% confidence interval. 3. Mercury contents in normal human blood differed from person to person (p<0.01), and the variability of the measurements was negligible (p>0.05). 4. Mercury in the blood was contained much higher in erythrocytes than in plasma (p<0.01), showing the geometric means of $21.0{\pm}1.25{\mu}g/100ml$ in red blood cells and $14.3{\pm}1.62{\mu}g/100ml$ in plasma, respectively. 5. Mercury contents in normal human blood had a relationship of power function with mercury excretion in urine corrected with a gram of creatinine excretion per liter of urine (p<0.10).