• Journal of Pharmacopuncture
• /
• 제23권1호
• /
• pp.1-7
• /
• 2020

Nicotine, primary component of tobaco produces craving and withdrawal effect both in humans and animals. Nicotine shows a close resemblance to other addictive drugs in molecular, neuroanatomical and pharmacological, particularly the drugs which enhances the cognitive functions. Nicotine mainly shows its action through specific nicotinic acetylcholine receptors located in brain. It stimulates presynaptic acetylcholine receptors thereby enhancing Ach release and metabolism. Dopaminergic system is also stimulated by it, thus increasing the concentration of dopamine in nuclear accumbens. This property of nicotine according to various researchers is responsible for reinforcing behavioral change and dependence of nicotine. Various researchers have also depicted that some non dopaminergic systems are also involved for rewarding effect of nicotinic withdrawal. Neurological systems such as GABAergic, serotonergic, noradrenergic, and brain stem cholinergic may also be involved to mediate the actions of nicotine. Further, the neurobiological pathway to nicotine dependence might perhaps be appropriate to the attachment of nicotine to nicotinic acetylcholine receptors, peruse by stimulation of dopaminergic system and activation of general pharmacological changes that might be responsible for nicotine addiction. It is also suggested that MAO A and B both are restrained by nicotine. This enzyme helps in degradation dopamine, which is mainly responsible for nicotinic actions and dependence. Various questions remain uninsurable to nicotine mechanism and require more research. Also, various genetic methods united with modern instrumental analysis might result for more authentic information for nicotine addiction.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 한국표면공학회 2009년도 추계학술대회 초록집
• /
• pp.190-191
• /
• 2009

최근 환경오염물질을 제거하기 위한 방법으로 광촉매를 이용한 기술들이 다양하게 활용되고 있다. 본 연구에서는 높은 비표면적을 갖는 광촉매를 제조하기 위해, 전기화학적인 방법인 양극 산화법을 사용하여 기지 Ti 금속 표면에 기공성 형태의 광촉매용 $TiO_2$를 제조하고, 염료분해 반응을 통해 광촉매의 효율을 조사하였다. 또한 염료분해 효율을 높이기 위해 $H_3(BO_3)_3$를 첨가하여 염료분해 반응에 미치는 영향에 대해 조사하였다.

• Bulletin of the Korean Mathematical Society
• /
• 제58권3호
• /
• pp.609-616
• /
• 2021

We study the solvability of the Fermat's matrix equation in some classes of 2-by-2 matrices. We prove the Fermat's matrix equation has infinitely many solutions in a set of 2-by-2 positive semidefinite integral matrices, and has no nontrivial solutions in some classes including 2-by-2 symmetric rational matrices and stochastic quadratic field matrices.

• Journal of the Korean Society of Food Science and Nutrition
• /
• 제38권4호
• /
• pp.409-414
• /
• 2009

The aim of this study was to investigate the ameliorating effects of deer antler extract on the learning and memory impairments induced by the administration of scopolamine (2 mg/kg, i.p.) in rats. Tacrine was used as a positive control agent for evaluating the cognition enhancing activity of deer antler extract in scopolamine-induced amnesia models. The results showed that the deer antler extract-treated group (200 mg/kg, p.o.) and the tacrine-treated group (10 mg/kg, p.o.) significantly ameliorated scopolamine-induced amnesia based on the Morris water maze test. Although there was no statistical significance of brain ACh contents among the experimental groups, the brain ACh contents of the deer antler extract-treated group was slightly higher than that of the scopolamine-treated group. The inhibitory effect of deer antler extract on the acetylcholinesterase activity in the brain was significantly lower than that of scopolamine-treated group. The tacrine- and the deer antler-treated groups reduced the MAO-B activity compared to the scopolamine-treated group, but not significantly. These results suggest that the deer antler extract could be an effective agent for the prevention of the cognitive impairment induced by cholinergic dysfunction.

• YAKHAK HOEJI
• /
• 제42권1호
• /
• pp.101-107
• /
• 1998

The antiparkinsonian agent l-deprenyl, a selective monoamine oxidase (MAO)-B inhibitor, is metabolized in part to l-methamphetamine and l-amphetamine. l< /I>-Deprenyl was evaluated for amphetamine and methamphetamine-like discriminative stimulus effects in rats and its mechanism of action was investigated. Rats were trained under a 5-response, fixed ratio schedule of stimulus-shock termination or a 10-response. Fixed-ratio schedule of food-presentation which discriminate between d-amphetamine (1mg/kg, i.p.) and saline or d-methamphetamine (1mg/kg, i.p.) and saline in a two-lever, operant conditioning procedure. Full generalization was obtained to d-amphetamine (1~3mg/kg). d-methamphetamine (1~3mg/kg) and l-deprenyl (17~30mg/kg) under both the food presentation and stimulus shock termination schedule. l-Deprenyl has dose-dependent amphetamine-and methamphetamine-like discriminative stimulus properties in rats only at doses of 17 and 30mg/kg. Reversible MAO-B inhibitor, RO 16-6491 didn`t show any amphetamine-like discriminative properties. Aromatic amino acid decarboxylase inhibitor, NSD 1015 decreased % responding of l-deprenyl in the methamphetamine-trained rats under the stimulus-shock termination schedule. SKF-525A produced partial inhibition of methamphetamine-like discriminative effects of l-deprenyl under the food presentation schedule. These results suggest that l-deprenyl has no abuse liability at the therapeutic range but there needs some caution at high doses and furthermore, drug discrimination studies under the food presentation and shock termination schedule are useful for the assessment of abuse liability of psychostimulants.

• Bulletin of the Korean Chemical Society
• /
• 제35권5호
• /
• pp.1337-1342
• /
• 2014

A novel and convenient route for the synthesis of a series of thalidomide derivatives is described. Compound 2 was cyclized with different amines under alkaline condition to obtain 4-nitro substituted phthalimidines 3a-d. Hydroxylactams 4a-d were produced via bromination and hydroxylation. Different acyl chlorides were reacted with hydroxylactams to provide the desired esters 5a-d. All compounds were evaluated by MTT assay for their inhibitory activities against HCT-116, MG-63, MCF-7, HUVEC and HMVEC cell lines in vitro. Most of them showed no obvious cytotoxic effect on normal human cells, compounds 4a-d, $5a_2$, $5a_4$, $5a_5$, $5b_2$, $5c_2$ and $5d_2$ exhibited potent antitumor activities, among which compounds $5a_2$ and $5b_2$ were more effective than 5-FU.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 한국건축시공학회 2014년도 추계 학술논문 발표대회
• /
• pp.53-54
• /
• 2014

This study evaluates engineering properties of mortar using lightweight fine aggregate made by bottom ash discharged air cooling process according to grading. Then we confirm possibility of use as lightweight fine aggregate. Consequently, Mix using bottom ash need additional examination for a change with the passage of time of flow. Also, mix of S indicates similar compressive strength with mix of Plain and 16% decrease of unit weight compared to mix of Plain; while mix of B indicates 10% decrease of compressive strength and 16% decrease of unit weight. Therefore, this study shows that mix of S and B is superior compared with other mix.

• Archives of Pharmacal Research
• /
• 제10권2호
• /
• pp.142-147
• /
• 1987

Fourteen kinds of medicinal plants were screened for determining inhibitory activities on monoamine oxidase B. The extracts of Artemisia Messer-Schmidtiana (herba), Chrysanthemum indicum(flos), Ericibe obtusifolia (radix et rhizoma) and Sophora japonica (flos) strongly inhibited the enzyme. Among them, Chrysanthemi flos was chosen for elucidating its active principles, and some flavonoids were isolated and identified as acasetin (I), 5, 7-dihydroxy chromone (II), diosmetin (III), apigenin (IV), eriodictyol (V) and luteolin (VI).$IC_{50} were determined as following: 1, 2.46;II, 0.19; III, 2. 11mM, and the others showed weak inhibition.

• Journal of Physiology & Pathology in Korean Medicine
• /
• 제18권6호
• /
• pp.1666-1685
• /
• 2004

This present study was designed to screen medicinal plants for the treatment of brain diseases such as Parkinson's disease or aging. We tested the effects of the water extracts from 38 species medicinal plants on antioxidant capacity, monoamine oxidase B (MAO-B) inhibitory activity, acetylcholinesterase (AChE) inhibition and antiperoxidation activity in vitro. The water extracts from 38 species were tested on their antioxidant activity using radical scavenging effects against ABTS+. The water extract of C. sappan was showed the highest antioxidant capacity, the antioxidant activity at 1 Jig of herbal extract being 0.38mM TE. Lipid peroxidation in brain homogenates induced by NADPH and ADP-Fe/sup 2+/ was strong inhibited by C. sappan and R. palmatum extracts. Among the 38 medicinal plants investigated, R. palmatum showed significant biological activity (antioxidant capacity, MAO-B inhibiory activity, and AChE inhibitory activity). The protective efficacy of R. palmatum water extract on 1-methyl-4­phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism and its possible mechanism were studied in C57BL/6 mice. Treatment of R. palmatum water extract protected biomacromolecules such as lipids from oxidative damage induced by MPTP. The content of MDA in brain tissue was decreased significantly by R. palmatum extract. These results suggest that R. palmatum water extract plays on effective role in attenuating MPTP-induced neurotoxicity in mice. This protective effect of R. palmatum might be estimated the result from the inhibitory activity on monoamine oxidase B and the enhancement of antioxidant activity.

• Elastomers and Composites
• /
• 제48권1호
• /
• pp.61-66
• /
• 2013

A family of Cr(III) complexes supported on tridentate dibenzimidazolyl ligands having a general formula: $[N(CH_3)(CH_2)_2(Bm-R)_2]CrCl_3$ [where Bm = benzimidazolyl, R = H (3a); -Me(3b); -Bn (3c)] have been synthesized and utilized them for the trans-1,4-specific polymerizations of 1,3-butadiene (BD), activated with methylalumoxane (MAO). The activity of BD polymerizations was sensitive to the type of ligand on the Cr metal, so that the activity decreases in the order of 3a > 3c > 3b. All the catalysts combined with MAO yielded polybutadienes with perfect trans-1,4 structure with moderate molecular weight.