• YAKHAK HOEJI
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• v.57 no.2
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• pp.77-86
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• 2013

The neuroprotective effects of herbal ethanol extract (GP-EX) from Gynostemma pentaphyllum on dopamine neurons in animal model of Parkinson's disease (PD) were investigated. Rats and mice were administered with rotenone (2.5 mg/kg) for 28 days and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg) for 5 days for the PD models, respectively and the animals were simultaneously treated with GP-EX (30 mg/kg, daily). After preparing the PD models, the animals were also administered with L-DOPA (10 mg/kg) for 14 days with or without GP-EX treatment. Treatment with GP-EX (30 mg/kg) inhibited the rotenone- and MPTP-induced neurotoxic effects in dopamine neurons of rats or mice, which was determined by the numbers of tyrosine hydroxylase-immunohistochemical staining survival cells, as well as the levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid. GP-EX (30 mg/kg) also showed the protective effects on neurotoxicity which was induced by long-term administration of L-DOPA (10 mg/kg) in rotenone- and MPTP-induced animal model of PD. The used doses of GP-EX (30 mg/kg) did not produce any signs of toxicity, such as weight loss, diarrhea, or vomiting, in rats and mice during the treatment periods. These results suggest that GP-EX has the protective functions against chronic L-DOPA-induced neurotoxic reactions in dopamine neurons of rotenone- and MPTP-induced animal model of PD. Therefore, the natural GP-EX may be beneficial in the prevention of PD progress and L-DOPA-induced neurotoxicity in PD patients.

• Membrane Journal
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• v.21 no.3
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• pp.290-298
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• 2011

The influence of co-existing gases on the hydrogen permeation was studied through a Pd-coated $V_{53}Ti_{26}Ni_{21}$ alloy membrane. The hydrogen permeation characteristics of Pd-coated $V_{53}Ti_{26}Ni_{21}$ alloy membrane have been investigated in the pressure range 1-3 bar under pure hydrogen and hydrogen mixture gas with carbon dioxide and carbon monoxide at $450^{\circ}C$. Preliminary hydrogen permeation experiments have been confirmed that hydrogen flux was $5.36mL/min/cm^2$ for a Pd-coated $V_{53}Ti_{26}Ni_{21}$ alloy membrane (thick: 0.5 mm) using pure hydrogen as the feed gas. In addition, hydrogen fluxes were 4.46, 5.20, $3.91mL /min/cm^2$ for$V_{53}Ti_{26}Ni_{21}$ alloy membrane using $H_2/CO_2$, $H_2/CO$ and $H_2/CO_2/CO$ as the feed gas respectively. Therefore, the hydrogen permeation flux decreased with decrease of hydrogen partial pressure irrespective of temperature and pressure when $H_2/CO_2$, $H_2/CO$ and $H_2/CO_2/CO$ mixture applied as feed gas respectively and permeation fluxes were satisfied with Sievert's law in different feed conditions. It was found from XRD results after permeation test that the Pd-coated $V_{53}Ti_{26}Ni_{21}$ alloy membrane had good stability and durability for various mixtures feeding condition.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2947-2952
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• 2013

Three coordination polymers, [$ML_2(H_2O)_2$] (M = Co (1), Ni (2), Mn (3)), were prepared from metal acetates ($M(CH_3COO)_2{\cdot}4H_2O$) and 3-pyridinepropionic acid ($HL=(3-py)-CH_2CH_2COOH$) by solvent-layer methods. By contrast, a discrete molecular compound, trans-[$Pd(HL)_2Cl_2$] (4), was synthesized by replacing benzonitrile (PhCN) ligands in trans-[$Pd(PhCN)_2Cl_2$] with HL under microwave-heating conditions. Compounds 1-3 have a 2D framework, and compound 4 contains a square-planar Pd metal.

• Analytical Science and Technology
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• v.5 no.4
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• pp.349-358
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• 1992

The direct determination of lead in the whole-blood by graphite furnace atomic absorption spectrometric analysis was carried out by using the sample which was diluted five-fold with 1% Triton X-100. Matrix modification was tried to remove the interferences of blood matrix and also to get the optimum analytical condition. Good agreement with certificated values in reference materials(bovine blood) supplied by comparison program in Japan was obstained when 1% $(NH_4)_2HPO_4$ as matrix modifier and ashing temperature, $700^{\circ}C$ were used or 1% $(NH_4)_2HPO_4$ and 0.1% $PdCl_2$ as matrix modifier and ashed at $700^{\circ}C$. Standard deviations were appeared as 2.2~6.3% for 1% $(NH_4)_2HPO_4$ and 3.1~9.1% for 1% $(NH_4)_2HPO_4$ and 0.1% $PdCl_2$ in the range of $31{\sim}624{\mu}gPb/l$.

• Tuberculosis and Respiratory Diseases
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• v.82 no.3
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• pp.227-233
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• 2019

Background: Programmed death-ligand 1 (PD-L1), a transmembrane protein, binds to the programmed death-1 (PD-1) receptor, and anti-PD-1 therapy enables immune responses against tumors. This study aimed to assess clinical characteristics of PD-L1 expression using immunohistochemistry among Korean patients with lung cancer. Methods: We retrospectively reviewed the data of patients with pathologically proven lung cancer from a single institution. PD-L1 expression determined by Tumor Proportion Score (TPS) was detected using 22C3 pharmDx (Agilent Technologies) and SP263 (Ventana Medical Systems) assays. Results: From July 2016 to July 2017, 267 patients were enrolled. The main histologic type was adenocarcinoma (69.3%). Most participants were smokers (67.4%) and had clinical stage IV disease (60.7%). In total, 116 (42%) and 58 (21%) patients had TPS ${\geq}1%$ and ${\geq}50%$, respectively. The patients were significantly older in TPS ${\geq}1%$ group than in TPS <1% group ($64.83{\pm}9.38years$ vs. $61.73{\pm}10.78years$, p=0.014), not in TPS ${\geq}50%$ cutoff value ($64.69{\pm}9.39$ vs. $62.36{\pm}10.51$, p=0.178). Regarding histologic grade, higher proportions of poorly differentiated tumor were observed in the TPS ${\geq}1%$ (40.8% vs. 25.8%, p=0.020) and TPS ${\geq}50%$ groups (53.2% vs. 27.2%, p=0.004). Among 34 patients examined with 22C3 and SP263 assays, 27 had positive results in both assays, with a cutoff of TPS ${\geq}1%$ (r=0.826; 95% confidence interval, 0.736-0.916). Conclusion: PD-L1 expression, defined as TPS ${\geq}1%$, was related to older age and poorly differentiated histology. There was a similar distribution of PD-L1 expression in both 22C3 and SP263 results.

• Journal of Sensor Science and Technology
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• v.5 no.4
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• pp.41-46
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• 1996

The Pd/Pt gate MISFET type hydrogen sensors, for detecting dissolved hydrogen gas in the transformer oil, were fabricated and their characteristics were investigated. These sensors including diffused resister heater and temperature monitoring diode were fabricated on the same chip by a conventional silicon process technique. The differential pair plays a role in minimizing the intrinsic voltage drift of the MISFET. To avoid the drift of the sensors induced by the hydrogen, the gate insulators of both FETs were constructed with double layers of silicon dioxide and silicon nitride. In order to eliminate the blister formation on the surface of the hydrogen sensing gate metal, Pt and Pd double metal layers were deposited on the gate insulator. The hydrogen response of the Pd/Pt gate MISFET suggests that the proposed sensor can detect the dissolved hydrogen in transformer oil with 40mV/10ppm of sensitivity and 0.14mV/day of stability.

• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.19-24
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• 2001

A solvent sublation has been studied for the determination of trace Au(III), Pt(IV) and Pd(II) in waste water with their complexes of 2-mercaptobenzothiazole (MBT). Experimental conditions such as the concentration of HCl, the amount of MBT as a ligand, the type and amount of surfactants, bubbling rate and time, and the type of organic solvent were optimized for the solvent sublation, i.e., 25.0 mL of 2.0 M HCl solution and 30mL of 0.4%(w/v) MBT ethanolic solution were added to a 1.0 L sample to form stable complexes. The addition of 4.0 mL of 1 ${\times}$$10^{-3}$ M CTAB (cetyltrimehtylammonium bromide) solution was needed for the effective flotation accomplished by bubbling nitrogen gas at the rate of 40.0 mL/min for 35 minutes. As a solvent, 20.0 mL of MIBK (methylisobuthylketone) was used to extract the floated complexes. The procedure was applied to three kinds of waste waters. Au(III) was determined as 0.68 ng/mL and 0.98 ng/mL respectively for final washed water of two plating industries in Banwol. Pd(II) and Pt(IV) were not detected in any of the three samples. The recovery, which was obtained with analyte-spiked samples, were 95-120%.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.106-112
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• 2008

Parkinson's disease (PD) progresses severely by a gradual loss of dopaminergic neurons in the substantia nigra (SN). Epidemiological studies showed that the incidences of PD were reduced by smoking of which the major component, nicotine might be neuroprotective. But the function of nicotine, which might suppress the incidences of PD, is still unknown. Fortunately, recently it was reported that a glial reaction and inflammatory processes might participate in a selective loss of dopaminergic neurons in the SN. The levels of tumour necrosis factor (TNF)-${\alpha}$ synthesised by astrocytes and microglia are elevated in striatum and cerebrospinal fluid (CSF) in PD. TNF-${\alpha}$ kills the cultured dopaminergic neurons through the apoptosis mechanism. TNF-${\alpha}$ release from glial cells may mediate progression of nigral degeneration in PD. Nicotine pretreatment considerably decreases microglial activation with significant reduction of TNF-${\alpha}$ mRNA expression and TNF-${\alpha}$ release induced by lipopholysaccharide (LPS) stimulation. Thus, this study was intended to explore the role of nicotine pretreatment to inhibit the expressions of TNF-${\alpha}$ mRNA in human fetal astrocytes (HFA) stimulated with IL-$1{\beta}$. The results are as follows: HFA were pretreated with 0.1, 1, and $10{\mu}g/mL$ of nicotine and then stimulated with IL-$1{\beta}$ (100 pg/mL) for 2h. The inhibitory effect of nicotine on expressions of TNF-${\alpha}$ mRNA in HFA with pretreated $0.1{\mu}g/mL$ of nicotine was first noted at 8hr, and the inhibitory effect was maximal at 12 h. The inhibitory effect at $1{\mu}g/mL$ of nicotine was inhibited maximal at 24 h. Cytotoxic effects of nicotine were noted above $10{\mu}g/mL$ of nicotine. Moreover, Nicotine at 0.1, 1 and $10{\mu}g/mL$concentrations significantly inhibited IL-$1{\beta}$-induced TF-${\kappa}B$ activation. Collectively, these results indicate that in activated HFA, nicotine may inhibit the expression of TNF-${\alpha}$ mRNA through the pathway which suppresses the NF-${\kappa}B$ activation. This study suggests that nicotine might be neuroprotective to dopaminergic neurons in the SN and reduce the incidences of PD.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1567-1574
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• 2007

A study was carried out to study the response of total purine derivatives (PD) excretion in urine to determine microbial N (MN) supply at four fixed levels of feed intake (namely 95, 80, 60 and 40% of voluntary intake). The crossbred (CB) calves were allocated according to a $4{\times}4$ Latin Square Design and fed wheat straw and concentrate (1:1). The rate of PD excretion (mmol/d) as a linear function of feed intake was 15.85/kg DMI and 20.12/kg DOMI. Based on the endogenous and PD excretion rates obtained in this study, a relationship between daily urinary PD excretion (Y, mmol) and daily microbial protein supply (X, mmol) was developed for crossbred calves as Y = 0.83X+0.296 kg $W^{0.75}$. The derived microbial N values using this equation differed (p<0.001) among the 4 groups and was the highest in L-95 followed by L-80, L-60 and L-40. The relationship between urinary nitrogen loss (Y, g/d) and DOMI (X, kg/d) was established as: Y = 6.038X+21.753 ($r^2$ = 0.663, p<0.01). When urinary excretion of PD (Y, mmol/d) was plotted against intake of DM and DOM (X, kg/d), the equations obtained were: Y = 7.1711X+8.674 ($r^2$ = 0.889, p<0.01) and Y = 12.434X+7.683 ($r^2$ = 0.896, p<0.01), respectively. The proportional contribution of allantoin and uric acid to total PD remained stable irrespective of level of feed intake. Similarly, urinary excretion of creatinine did not differ (p>0.05) between animals fed at different levels. The MN supply was the highest to animals at intake levels L-95, and decreased linearly with corresponding decrease in feed intake. However, the MN supply when expressed per kg DOMI remained statistically (p>0.05) similar irrespective of level of intake. The results revealed that the excretion of urinary purine derivatives were positively correlated with the level of feed intake as well as rumen microbial supply and thus it could be a good indicator for measuring the microbial protein supply and nutritional status of animals.

• Biomedical Science Letters
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• v.3 no.2
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• pp.169-175
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• 1997

The hypoglycemic and metabolic effects of Commelina communis L. extract were investigated in alloxan-induced diabetic rats. The increased blood glucose level in the diabetic rats was sinificantly lowered with the treatments of the plant protein extract. Administration of the plant extract ellicited the significant increase of glucose-6-phosphate dehydrogenase (G6PD) activity in liver of alloxan-induced rats. Three isozyme patterns(band I, II & III : in order decreasing mobility) of G6PD were found when normal rat liver extract were subjected to electrophoresis on native polyacrylamide gel. On the other hand, G6PD band patterns of alloxan-induced rat liver extract were found band II isozyme missing. By treatment of plant extract in alloxan-induced rats has been showed pattern the recovery of missing band patterns. This indicates that changes of the G6PD isozyme might be related to the cellular process of diabetes.