• Journal of Mechanical Science and Technology
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• 제18권6호
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• pp.1036-1041
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• 2004

A newly designed pressure-scanning slit viscometer is developed to combine an optical device without refraction while measuring blood viscosity over a range of shear rates. The capillary tube in a previously designed capillary viscometer was replaced with a transparent slit, which is affordable to mount optical measurement of flowing blood cells. Using a pressure transducer, we measured the change of pressure in a collecting chamber with respect to the time, p(t), from which the viscosity and shear rate were mathematically calculated. For water, standard oil and whole blood, excellent agreement was found between the results from the pressure-scanning slit viscometer and those from a commercially available rotating viscometer. This new viscometer overcomes the drawbacks of the previously designed capillary viscometer in the measuring whole blood viscosity. First, the pressure-scanning slit viscometer can combine an optical instrument such as a microscope. Second, this design is low cost and simple (i.e., ease of operation, no moving parts, and disposable).

• Restorative Dentistry and Endodontics
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• 제47권4호
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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 Microbiology and Biotechnology
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• 제25권2호
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• pp.255-267
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• 2015

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease, a chronic debilitating disease affecting ruminants worldwide. In the present study, we aimed to determine the major gene networks and pathways underlying the immune response to MAP infection using whole-blood cells, as well as provide the potential transcriptional markers for identifying the status of MAP infection. We analyzed the transcriptional profiles of whole-blood cells of cattle identified and grouped according to the presence of MAP-specific antibodies and the MAP shed by them. The grouping was based on the results obtained by ELISA and PCR analyses as follows: i) Test1 group: MAP-negative results obtained by ELISA and positive results obtained by PCR; ii) Test2 group: MAP-positive results obtained by ELISA and negative results obtained by PCR; iii) Test3 group: MAP-positive results obtained by ELISA and positive results obtained by PCR; iv) uninfected control: MAP-negative results obtained both by ELISA and PCR analysis. The results showed down-regulated production and metabolism of reactive oxygen species in the Test1 group, activation of pathways related to the host-defense response against MAP (LXR/RXR activation and complement system) in the Test2 and Test3 groups, and anti-inflammatory response (activation of IL-10 signaling pathway) only in the Test3 group. Our data indicate a balanced response that serves the immune-limiting mechanism while the host-defense responses are progressing.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2947-2950
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• 2007

A 3D human ventricular model is proposed to simulate an integrative analysis of heart physiology and blood hemodynamics. This consists of the models of electrophysiology of human cells, electric wave propagation of tissue, heart solid mechanics, and 3D blood hemodynamics. The 3D geometry of human heart is discretized to a finite element mesh for the simulation of electric wave propagation and mechanics of heart. In cellular level, excitations by action potential are simulated using the existing human model. Then the contraction mechanics of a whole cell is incorporated to the excitation model. The excitation propagation to ventricular cells are transiently computed in the 3D cardiac tissue using a mono-domain method of electric wave propagation in cardiac tissue. Blood hemodynamics in heart is also considered and incorporated with muscle contraction. We use a PISO type finite element method to simulate the blood hemodynmaics in the human ventricular model.

• IMMUNE NETWORK
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• 제16권5호
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• pp.296-304
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• 2016

It has been reported that fatty acid binding proteins (FABPs) do not act only as intracellular mediators of lipid responses but also have extracellular functions. This study aimed to investigate whether extracellular liver type (L)-FABP has a biological activity and to determined serum L-FABP levels in patients with end-stage renal disease (ESRD). We isolated L-FABP complementary deoxyribonucleic acid (cDNA) from the Huh7 human hepatocarcinoma cell line and expressed the recombinant L-FABP protein in Escherichia coli. A549 lung carcinoma and THP-1 monocytic cells were stimulated with the human recombinant L-FABP. Human whole blood cells were also treated with the human recombinant L-FABP or interleukin (IL)-1α. IL-6 levels were measured in cell culture supernatants using IL-6 enzyme-linked immunosorbent assay (ELISA). Human recombinant L-FABP induced IL-6 in a dose-dependent manner in A549, THP-1 cells, and whole blood cells. The blood samples of healthy volunteers and patients with ESRD were taken after an overnight fast. The serum levels of L-FABP in healthy volunteers and ESRD patients were quantified with L-FABP ELISA. The values of L-FABP in patients with ESRD were significantly lower than those in the control group. Our results demonstrated the biological activity of L-FABP in human cells suggesting L-FABP can be a mediator of inflammation.

• 대한기계학회논문집B
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• 제30권4호
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• pp.314-319
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• 2006

To analyze in-vivo blood flow characteristics in a chicken embryo, in-vivo experiment was carried out using micro-PIV technique. Because endothelial cells in blood vessels are subject to shear stress of blood flow, it is important to get velocity field information of the placental blood flow. Instantaneous velocity fields of an extraembryonic blood vessel using a high-speed camera and intravital microscope. The flow images of RBCs were obtained with a spatial resolution of $20\times20{\mu}m$ in the whole blood vessels. The mean velocity field data confirm that the blood flow does show non-Newtonian fluid characteristic. The blood in a branched vessel merged smoothly without any flow separation into the main blood vessel with the presence of a slight bump. This in-vivo micro-PIV measurement technique can be used as a powerful tool in various blood flow researches.

• 한국임상수의학회지
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• 제7권2호
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• pp.451-469
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• 1990

The present study was carried out to investigate whether the aloe had a radioprotective effect in mice exposed to cobalt-60 gamma radiation or not. The survival ratio of mice for 30 days, hematopoiesis of blood-forming stem cells by spleen colony assay, chromosomal aberration frequency of bone marrow cells and histopathological findings of bone marrow were investigated. The survival ratios of aloe administered groups with concentration of 250, 500, 1,000 and 1,500mg for 3 days before irradiation and control group in cobalt-60 gamma irradiated mice(700rads whole body irradiation, dose rate of 50rads/min.) were 77.4, 79.3, 80.6, 90.0 and 53.1％, respectively. The survival ratios of pre-irradiation aloe administered groups were superior to those of post-irradiation aloe groups and control group. In spleen colony assay, Aloe vera administration before irradiation enhanced the recoveries of numbers of blood-forming stem cells of bone marrow of irradiated mice. There were decreased chromosomal aberrations of bone marrow cells at the first day after irradiation in aloe administered groups compared to that of control group. Histopathological findings in the bone marrow of irradiated mice were hypocellularity due to the depletion of myelocytes, abundant of fat vacuoles and these changes were weakened in aloe administered groups compared to that of control group.

• 대한화학회지
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• 제47권2호
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• pp.127-132
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• 2003

소의 타일레리아병 진단을 위해 DNA 추출과정 없이 전혈에서 바로 중합효소연쇄반응(PCR)을 통하여 T. buffeli(buffeli/orientalis/sergenti)의 16S rRNA 유전자 단편을 증폭시킨 뒤, 증폭된 DNA를 전기영동법으로 분석하는 방법을 개발하였다. 특이유전자 단편의 증폭을 위해 formamide를 사용하여 혈액세포를 용해시켰으며, 단백질의 응고를 줄이기 위해 낮은 반응온도를 사용하는 FoLT(Formamide Low Temp.) PCR법을 이용하였다. 전혈 100-200 nL를 바로 PCR 증폭에 사용하였으며, PCR 산물(816-bp DNA)은 전기영동법으로 분석하였다. 본 결과는 T. buffeli에 감염된 소의 혈액으로부터 정제된 DNA를 사용하여 얻은 실험결과와 잘 일치하였다.

• The Korean Journal of Physiology
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• 제29권2호
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• pp.217-223
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• 1995

Adenosine 5'-tetraphosphate (ATPP) was identified and quantified in extracts of rabbit platelets by elution of extracts containing authentic adenosine 5'-tetraphosphate and comparison of retention time with nucleotide standards using high-performance liquid chromatography technique. The amount of adenosine 5'-tetraphosphate was $0.62\;nmoles/10^{9}$ cells which was 62-fold lower than that of ATP but only 10-fold lower than that of ADP. During platelet aggregation induced by thrombin, adenosine 5'-tetraphosphate was released to a relatively high extent. The degradation rates and halflives of adenosine 5'-tetraphosphate were measured during incubation of platelets in whole blood, erythrocyte suspension and plasma, respectively. The results suggest that plasma contributes more than blood cells to the catabolism of adenosine 5'-tetraphosphate. The pattern of degradation indicates that ATPP may be degraded mainly to AMP by soluble enzymes in plasma and very slowly to ADP and/or AMP by ectoenzymes on blood cells such as erythrocyte. The nature of the enzymes responsible fer the degradation of adenosine 5'-tetraphosphate is yet to be identified.

• Journal of Pharmaceutical Investigation
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• 제32권4호
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• pp.285-290
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• 2002

In order to assay the efficacy of newly synthesized antiviral compounds, in vitro studies of their active intracellular phosphorylated metabolites were established as compared with Zidovudine (ZDV). Antiviral base analogs require intracellular phosphorylation prior to the inhibition of HIV replication. Therefore, antiviral drugs concentrations in plasma have not reflected any direct relationship with activity or toxicity. A method has been developed to measure the concentration of total phosphorylated metabolites inside peripheral blood mononuclear cells using modified commercial radioimmunoassay (RIA). ZDV 5'-monophosphate was synthesized and used as a procedural control for RIA modification. PBMCs were isolated from whole blood and incubated with ZDV for 20 h to allow metabolic phosphorylation. Viable cells were extracted overnight with 60% methanol. After evaporation, the extract was reconstituted in Tris buffer. Samples were split into two fractions, one of which was treated with alkaline phosphatase (AP) to liberate phosphate groups. Concentrations of phosphorylated metabolites were determined by subtracting thε concentration of non-AP-treated fraction from that of the treated fraction. Recovery of phosphorylated ZDV from cell extracts was approximately 90%, and reproducibility was acceptable (coefficients of variation <15% for concentrations${\geq}$0.25 ng/mL). Intracellular concentrations $(0.135{\sim}5.019\;nmole/10^6\;cells)$ followed a nonlinear dose-response relationship over the range $0.015{\sim}2.996mM$ extracellular ZDV, with concentration-dependant saturation.