• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.149-152
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• 2002

The effect of pressure on the catalytic properties of glutamate racemase from Aquifex pyrophilus, an extremophilic bacterium, was investigated. The activation volume for the overall reaction $({\Delta}V^{\neq})$ and catalysis $({{Delta}V_{cat}}^{\neq})$ was -96.97 ml/mol and 4.97 ml/mol, respectively, while the reaction volume for the substrate binding (${\Delta}V_{K_m^-1}$) was -101.94 ml/mol. The large negative ${\Delta}V^{\neq}$ for the overall reaction indicated that the pressurization of glutamate racemase resulted in enhanced catalytic efficiencies. In addition, this value was also due to the large negative ${Delta}V_{K_m^-1}$ for the substrate binding. The negative value of ${Delta}V_{K_m^-1}$ implied that the conformational changes in the enzyme molecule occurred during the substrate binding process, thereby increasing the degree of hydration. The small value of ${{Delta}V_{cat}}^{\neq}$suggested that the pressure did not affect the glutamate racemase catalysis after the substrate binding.

• Archives of Pharmacal Research
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• v.27 no.9
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• pp.968-972
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• 2004

A 1, 2-diglyceride-based multi-step colorimetric assay to measure the pancreatic lipase activ-ity was applied for the determination of the kinetic profiles of the lipase inhibition with a slight modification and the validity verification. With this assay method, our study revealed that platy-codin D, one of major constituents of Platycodi Radix, inhibits the pancreatic lipase activity in a competitive type, with the value of $K_1$ being 0.18${\pm}$0.02 mM. In addition, PO has affected the val-ues of $K_{m}$, app/ and $K_{cat}$/$K_{m}$ in a dose-dependent manner. The results shed a meaningful light on how PO mediates lipid metabolism in the intestinal tracts. On the other hand, since the revised assay is sensitive, rapid, and does not affect the accuracy to the kinetic properties, it is applica-ble not only to evaluation of the kinetic properties of the pancreatic lipase, but also to high-throughput screening of pancreatic lipase activity.

• YAKHAK HOEJI
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• v.35 no.6
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• pp.486-496
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• 1991

Spinal parasympathetic outflows originate in the sacral parasympathetic nuclei. The sacral parasympathetic nuclei receive inputs from the brainstem. Many areas in the medulla appear to influence sympathetic outflow of the spinal cord. Whether neurons in these areas of the medulla may project to the lumbosacral cord to affect the parasympathetic outflow has not been studied clearly. Thus, this study was intended to investigate origins of cells projecting from the medulla to the sacral parasympathetic nuclei of the spinal cord. In 3 cats, horseradish peroxidase (HRP) was injected into the lower lumbar spinal cord. HRP labeled neurons were found mainly in the following areas: nucleus retroambiguus, nucleus tractus solitarius, raphe complex and ventrolateral area of the rostral medulla. Most of these areas are known to be involved in regulation of sympathetic activity, and, thus, these results indicate that these areas are likely to affect the sacral parasympathetic outflow as they do for the sympathetic nerves.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1048-1052
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• 2004

A 1, 2-diglyceride-based multi-step colorimetric assay to measure the pancreatic lipase activity was applied for the determination of the kinetic profiles of the lipase inhibition with a slight modification and the validity verification. With this assay method, our study revealed that platycodin D, one of major constituents of Platycodi Radix, inhibits the pancreatic lipase activity in a competitive type, with the value of $K_I$ being 0.18${\pm}$0.02 mM. In addition, PD has affected the values of $K_{m,app}\;and\;K_{cat}/K_m$ in a dose- dependent manner. The results shed a meaningful light on how PD mediates lipid metabolism in the intestinal tracts. On the other hand, since the revised assay is sensitive, rapid, and does not affect the accuracy to the kinetic properties, it is applicable not only to evaluation of the kinetic properties of the pancreatic lipase, but also to highthroughput screening of pancreatic lipase activity.

• Applied Microscopy
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• v.8 no.1
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• pp.53-66
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• 1978

An attempt has been made to discriminate the synapses in the striatum consisting caudate nucleus, putamen and fundus striati of the cat with emphasis on the characteristic structures of axon terminals and postsynaptic profiles. The differentiation is based on the size and shape of vesicle in the bouton terminal, and the symmetrical or asymmetrical thickening the pre- and postsynaptic membrane. Four types of synapses could be differentiated: Type I: the bontons with asymmetrical,synaptic thickenings contain round 45 nm diameter vesicles and contact cell soma, dendritic shafts and dendritic spines (74%). Type II : the boutons contain round 45nm diameter vesicles and are associated with symmetrical membrane thickenings. These synapses are formed on the soma and dendritic shafts (6%). Type III: the boutons with symmetrical membrane thickenings contain 50-60 nm diameter pleomorphic vesicles, and contact soma and dendritic shafts (18%). Type IV: the terminals contain flattened vesicles ($25{\times}45 nm$) and are associated with symmetrical membrane thickenings. These synapses are found in contact with soma and dendritic shafts. Additionally, the bouton en passant, which is expanded from myelinated or unmyelinated axons containing round vesicles (45nm diameter) contacts the dendritic shaft or dendritic spine with asymmetrical membrane thickenings. Two unusual types of synapses, axo-axonic and dendro-dendritic, are found occasionally.

• The Journal of Internal Korean Medicine
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• v.35 no.2
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• pp.208-221
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• 2014

Purpose : Banhasasim-tang (BHSST) has been applied for treating the symptom of gastric stuffiness, which is similar to dyspepsia. The object of this study was to observe the healing effect of BHSST on the indomethacin (IND)-induced gastric ulcer in rats. Methods : Three different dosages of BHSST (400, 200 and 100 mg/kg) were orally administered 30 min before IND treatment; 6 hrs after IND treatment, the changes on the gross lesion scores, fundic histopathology, myeloperoxidase (MPO) activity, lipid peroxidation and antioxidant defense system (glutathione contents, catalase (CAT) and superoxide dismutase (SOD) activities) were observed, and compared with the activity of the synthetic anti-ulcer drug, a representative proton pump inhibitor omeprazole (OME) 10 mg/kg. Results : All three different dosages of BHSST treatment in the IND-induced gastric ulcer rats, significant and dose dependent decreased gastric damages - hemorrhagic gross lesions, gastric mucosa MPO levels and histopathological gastric ulcerative lesions - were detected as compared with the IND treated control rats. BHSST also strengthened the antioxidant defense systems - decreased the level of lipid peroxidation and CAT activity but increased the level of GSH and SOD activity, and BHSST 200 mg/kg showed similar anti-ulcerative effect as compared with OME 10 mg/kg. Conclusions : The results obtained in this study suggest that BHSST has favorable effects against IND-induced gastric damages, through significant and dose-dependent decreasing gastric damages and the strengthening of the body's antioxidant defense systems with direct anti-inflammatory effects.

• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.829-834
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• 2016

Free radicals originate due to the radiolysis of cytoplasmic water with low "Linear Energy Transfer" (LET) radiations. Naringenin (Ng) is a natural antioxidative compound found in citrus fruits. This study revealed that Naringenin (Ng) reduced the radiation damage of critical organs by scavenging oxidative free radicals. In the study, Ng was orally administrated to rats daily for 7 consecutive days, prior to whole body exposure to gamma-rays. The scavenging efficacy was evaluated biochemically by measuring the concentration of cytotoxic byproducts and the activity of enzymes relevant to oxidative free radicals, after extracting the organs from the exposed rat. We observed increased levels of malondialdehyde (MDA) concentration, and decrease in the activities of superoxide dismutase (SOD) and catalase (CAT) in the exposed control group. However, pretreatment with Ng significantly reduced the MDA concentration, and increased the activities of SOD and CAT, as compared to the control group, due to the free radical scavenging by Ng. The results indicate that Ng administration prior to irradiation could protect critical organs from radiation damage.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.172-177
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• 1989

Stereoselective solvolyses of optically active activated esters in the aggregate system of optically active polymeric surfactants containing imidazole and benzene moieties were performed. The catalyst polymers employed were copolymers of N-methacryloyl-L-histidine methyl ester (MHis) with N,N-dimethyl-N-hexadecyl-N-[10-(p-methacryloylo xyphenoxycarbonyl)-decyl]ammonium bromide(DEMAB). In the solvolyses of N-carbobenzoxy-D- and L-phenylalanine p-nitrophenyl esters (D-NBP and L-NBP) by polymeric catalysts, copoly(MHis-DEMAB) exhibited not only increased catalytic activity but also enhanced enantioselectivity as the mole ${\%}$ of surfactant monomers in the copolymers increased. The polymeric catalysts showed noticeable enantioselective solvolyses toward D- and L-NBP of the substrates employed. As the reaction temperature was lowered for the solvolyses of D- and L-NBP with the catalyst polymer containing 3.5 mole ${\%}$ of MHis, the increased reaction rate and enhanced enantioselectivity were observed. The coaggregative systems of the polymer and monomeric surfactants were also investigated. In the case of coaggregate system consisted of 70 mole ${\%}$ of cetyldimethylethylammonium bromide with polymeric catalyst showed maximum enantioselective catalysis, viz., $k_{cat}(L)/k_{cat}(D)$ = 2.85. The catalyst polymers in the sonicated solvolytic solutions were confirmed to form large aggregate structure by electron microscopic observation.

• The Journal of the Society of Stroke on Korean Medicine
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• v.10 no.1
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• pp.8-19
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• 2009

Scutellaria Radix, originated from Scutellaria baicalensis Georgi, is one of the most important medicine in traditional Oriental medicine, and possesses anti-bacterial activity and sedative effects, can be applied in the treatment of a range of conditions including diarrhea and hepatitis. It is reported that chronic global ischemia induces neuronal damage in selective, vulnerable regions of the brain, especially the hippocampus and cerebral cortex. In the present study, to investigate the effect of Scutellaria Radix extract on cerebral disease, the changes of regional cerebral blood flow and pial arterial diameter on ischemia/reperfusion state was determinated by Laser-Doppler Flowmetry and some parameters concerned with oxidative stress also measured. When SRe were administered for five days with the concentration of 100 mg/kg, GSH activity significantly increased. But SRe administeration showed no significant change in lipid peroxidation. When the activities of CAT, Cu, Zn-SOD and GSH were measured, CAT and GSH were activated by SRe administration. When 1 and 3 ㎍/㎖ SRe was applied to the neuronal cell cultures, the quantities of LDH was significantly reduced when compared with cultures treated only with NMDA. Through this study, it can be concluded that the ischemia/reperfusion induced brain stress may have contributed to cerebral damage in rats, and the present study provides clear evidence for the beneficial effect of SRe on ischemia induced brain injury.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.37-43
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• 1993

Electrical or chemical stimulation of many areas in the brainstem modulates activity of dorsal horn neurons (DHN). This is known to be mediated by a population of bulbospinal neurons. Yet, little is known about responses of DHNs to stimulation of the caudal ventrolateral medulla (CVLM). Thus, the purpose of the present study is to see if there is any change in activity of DHNs when CVLM is stimulated electrically. Thirty-one DHNs were recorded from dorsal horn of the spinal cord. Fourteen DHNs (45%) were classified as wide dynamic range neurons and 9 (19%) were high threshold cells, and 4 (13%) and 4 (13%) were deep and low threshold neurons, respectively. Among 31 neurons tested for responses to stimulation of CVLM, 21 DHNs (68%) were inhibited by the electrical stimulation of CVLM ($200{\mu}A,\;100{\mu}s$ duration, 100 Hz), and 9 cells (39%) did not show any change in neuronal activity. One neuron was excited by the stimulation. The electrical stimulation of CVLM not only inhibited spontaneous activity of DHNs but also inhibited evoked responses of DHNs to somatic stimulation in the receptive field. These data suggest that CVLM is one of the pain-modulatory areas that control transmission of ascending information of noxious input to the brain from the spinal cord.