• Journal of Mechanical Science and Technology
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• v.17 no.2
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• pp.296-309
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• 2003

The periodicity of the physiological flow has been the major interest of analytic research in this field up to now Among the mechanical forces stimulating the biochemical reaction of endothelial cells on the wall, the wall shear stresses show the strongest effect to the biochemical product. The objective of present study is to find the effects of velocity waveform on the wall shear stresses and pressure distribution along the artery and to present some correlation of the velocity waveform with the clinical observations. In order to investigate the complex flow phenomena in the bifurcated tube, constitutive equations, which are suitable to describe the rheological properties of the non-Newtonian fluids, are determined, and pulsatile momemtum equations are solved by the finite volume prediction. The results show that pressure and wall shear stresses are related to the velocity waveform of the physiological flow and the blood viscosity. And the variational tendency of the wall shear stresses along the flow direction is very similar to the applied sinusoidal and physiological velocity waveforms, but the stress values are quite different depending on the local region. Under the sinusoidal velocity waveform, a Newtonian fluid and blood show big differences in velocity. pressure, and wall shear stress as a function of time, but the differences under the physiological velocity waveform are negligibly small.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.341-344
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• 2002

Neurodegenerative disorders, like Alzheimer's disease, are often accompanied by reduced brain perfusion (cerebral blood flow). Using the intrinsic magnetic properties of water, arterial spin labeling magnetic resonance imaging (ASLMRI) can map brain perfusion without injection of radioactive tracers or contrast agents. However, accuracy in measuring perfusion with ASL-MRI can be limited because of contributions to the signal from stationary spins and because of signal modulations due to transient magnetic field effects. The goal was to optimize ASL-MRI for perfusion measurements in the aging human brain, including brains with Alzheimer's disease. A new ASL-MRI sequence was designed and evaluated on phantom and humans. Image texture analysis was performed to test quantitatively improvements. Compared to other ASL-MRI methods, the newly designed sequence provided improved signal to noise ratio improved signal uniformity across slices, and thus, increased measurement reliability. This new ASL-MRI sequence should therefore provide improved measurements of regional changes of brain perfusion in normal aging and neurodegenerative disorders.

• Journal of Mushroom
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• v.12 no.2
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• pp.77-81
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• 2014

Mushrooms are considered not only as food but also for source of physiologically beneficial medicines. The culinary-medicinal mushrooms may important role in the prevention of age-associated neurological dysfunctions, including Alzheimer's and Parkinson's diseases. Hericium erinaceus (H. erinaceus), is edible mushrooms, is a parasitic fungus that grows hanging off of logs and trees and well established candidate for brain and nerve health. H. erinaceus contains high amounts of antioxidants, beta-glucan, polysaccharides and a potent catalyst for brain tissue regeneration and helps to improve memory and cognitive functions. Its fruiting bodies and the fungal mycelia exhibit various pharmacological activities, including the enhancement of the immune system, antitumor, hypoglycemic and anti-aging properties. H. erinaceus stimulates the synthesis of Nerve Growth Factor (NGF) which is the primary protein nutrient responsible for enhancing and repairing neurological disorders. Especially hericenones and erinacines isolated from its fruitin body stimulate NGF, synthesis. This fungus is also utilized to regulate blood levels of glucose, triglycerides and cholesterol. H. erinaceus can be considered as useful therapeutic agents in the management and/or treatment of neurodegeneration diseases. However, this review focuses on in vitro, in vivo and clinical trials for neurodegerative disease.

• Biomolecules & Therapeutics
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• v.5 no.4
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• pp.390-401
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• 1997

In order to investigate the pharmacological properties of New Woohwangchungsimwon Liquid (NCL), effects of Woohwangchungsimwon Liquid (CL) and NCL were compared. In isolated rat aorta, NCL and CL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) without regard to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxation of NCL and CL. NCL and CL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NCL and CL significantly decreased heart rate. NCL and CL, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NCL and CL had no effects on parameters of action potential at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NCL and CL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between two preparations.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.188-195
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• 1993

Polyelectrolyte complexes and graft copolymers as biomaterials were synthesized from the water soluble cellulose derivatives. Polyelectrolyte complexes have been prepared from carboxymethyl cellulose (CMC) and gelatin. Graft copolymers(Mc-g-AA) were synthesized by grafting acrylic acid (AA) onto methyl cellulose(MC). (Mc-g-AA) and gelatin polyelectrolyte complexes were also prepared. The optimum conditions of each sample were investigated after chemical crosslinking or heat treatment. The preliminary results show that these materials might be interesting for biomedical applications.

• YAKHAK HOEJI
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• v.29 no.6
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• pp.367-374
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• 1985

The age-related changes of monoamine contents and monoamine oxidase (MAO) activities in the whole brain and blood pressures were measured and compared every week during the ages of 5 weeks to 12 weeks in two types of animals; (1) spontaneously hypertensive rats (SHR) and (2) normotensive Sprague-Dawley rats (NR). Blood pressures in SHR began to rise at the ages of 7 or 8 weeks and were significantly higher thereafter than in NR. Abnormally low MAO activities in the brain of SHR were detected from the ages of 8 weeks. Comparisons were also made between brain monoamine-norepinephrine, dopamine and 5-hydroxytrytamine contents of SHR and those of NR at the same ages throughout the test period. In SHR, none of those monoamine values was consistently higher or lower than in NR during the test period. Protein contents of the brain between SHR and NR were not significantly different at any ages. These observations suggest that the abnormally low MAO activities in SHR brain may be one of the underlying neurological factors for the susceptibilities to hypertension and the deficit of MAO activities may be due to the changes in properties rather than in amount of this enzyme.

• Archives of Pharmacal Research
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• v.18 no.3
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• pp.169-172
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• 1995

The changes in blood pressure may relate to the alterations of the responsiveness to vasoconstrictors and vasodilators, and these alterations can arise the modifications in the properties of angiotensin II (AII) receptor. In order to examine the changes of AII receptor in the hypertensive mechanism of renin-dependent hypertensive rats (RHRs; two-kidney, one-ligated type), we compared the equilibrium binding characteristics of $[^3H]$All in adrenal cortex and medulla from RHRs and normotensive rats. The dissociation constants of AII binding in both tissues of RHRs were very similar to those in the respective tissue of normotensive rats. However, the maximum binding was increased from 805 to 1050 fmole/mg protein in the adrenal cortex of RHRs, and decreased from 172 to 126 fmole/mg protein in the adrenal medulla of RHRs. These results imply that the up- and down-regulation of the All receptor population on the cell surface of adrenal glands from RHRs are consorted with the elevation of blood pressure and the activation of renin-angiotensin system.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.66-78
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• 1999

In order to investigate the pharmacological properties of New Wonbang Woohwangchungsimwon Liquid (NSCL), effects of Wonbang Woohwangchungsimwon Liquid (SCL) and NSCL were compared. In isolated rat aorta, NSCL and SCL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) regardless to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxing effect of NSCL and SCL. NSCL and SCL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NSCL and SCL significantly decreased heart rate. NSCL and SCL, at high doses, had a negative inotropic effect that was a decrease of left ventricular developed pressure and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NSCL and SCL had no effects on parameters of action potential such as resting membrane potential, action potential amplitude, APD$_{90}$ and V$_{max}$ at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NSCL and SCL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between cardiovascular effects of two preparations.s.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.89-96
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• 1999

CJ-50002 is an oral vaccine against V.vulnificus infection composed of whole cell lysate of V. vulnificus. The general pharmacological properties of CJ-50002 were evaluated in various animals and in vitro system. CJ-50002 at oral doses of 0.2, 2 and 20 mg/kg had no effect on general behavior in mice, chromo- and electro-convulsions in mice, writhing syndrome induced by acetic acid in mice, body temperature in rats, charcoal meal propulsion in mice and urine and electrolytes excretion in rats. However, oral administration of CJ-50002 at dose of 20 mg/kg prolonged the hexobarbital-inuced sleeping inducing time in mice. In anesthetized dogs, CJ-50002 showed no effect on blood pressure, heart rate and ECG but decreased the respiratory rate and femoral blood flow at dose of 20 mg/kg. p.o. CJ-50002 had no effect on the contractile response of the isolated guinea pig ileum to various spasmogen at concentrations of 0.2, 2 and 20 $\mu\textrm{g}$/ml, respectively. Since these pharmacological effects of CJ-500o2 were observed at dose much greater than those in clinical use (approximately 0.16 mg/kg, p.o.), it is likely that this vaccine may be relatively free of undesirable effects in clinical practice.

• Biomolecules & Therapeutics
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• v.14 no.4
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• pp.194-201
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• 2006

The general pharmacological properties of GCSB-5, a herbal formulation consisting of 6 Oriental herbs(Ledebouriellae Radix, Achyranthis Radix, Acanthopanacis Cortex, Cibotii Rhizoma, Glycine Semen and Eucommiae Cortex), were investigated in mice, rats, guinea pigs and rabbits. The administration of GCSB-5 had no effect on general behavior, and did not influence the central nervous system. Mean blood pressure, heat1 and respiratory rate and contractile response of the isolated guinea pig atrium were unaffected by the treatment of GCSB-5. Addition of GCSB-5 did not cause spontaneous relaxation and contraction of the isolated guinea pig ileum and rat uterus. And also, GCSB-5 had no effect on the gastrointestinal system and the blood system of the animals examined in this study. GCSB-5, at higher doses(1,000 and 3,000 mg/kg), increased the urinary excretion of electrolytes, however, the urine volume and pH in rats were unaffected. Taken together, these results indicate that GCSB-5 does not induce any adverse effects in experimental animals and is expected to have no significant general pharmacological activities.