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        검색결과 87

        1.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We successfully synthesize water-dispersible CTAB-capped CdSe@ZnS quantum dots with the crystal size of the CdSe quantum dots controlled from green to orange colors. The quenching effect of Fe(DTC)3 is very efficient to turn off the emission light of quantum dots at four molar ratios of the CdSe quantum dots, that is, the effective covering the surface of quantum dots with Fe(DTC)3. However, the reaction with Fe(DTC)3 for more than 24 h is required to completely realize the quenching effect. The highly quenched quantum dots efficiently detect nitric oxide at nano-molar concentration of 110nM of NO with 34% of recovery of emission light intensity. We suggest that Fe(DTC)3-hybridized CdSe@ZnS quantum dots are an excellent fluorescence resonance energy transfer probe for the detection of nitric oxide in biological systems.
        4,000원
        2.
        2022.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Plant-derived compounds have been reported to possess anti-inflammatory abilities contained inhibited β-hexosaminidase, ROS and NO release. Essential oils are natural volatile complex compounds that are characterized by a strong scent and produced by aromatic plants as various plant-derived compounds. The essential oil extracted from Zanthoxylum coreanum Nakai (Z. coreanum) has various functional properties; however, little information is available regarding its anti-allergic inflammatory. A total of 17 compounds were detected in Z. coreanum oil, and the main component was estragole (50.86%). The tested Z. coreanum oil and estragole statistically inhibited the release of β-hexosaminidase induced by antigen stimulation in RBL-2H3 cells. This Z. coreanum oil and estragole may stimulate the secretion of active oxygen (ROS) or nitric oxide (NO) which are considered to involved in anti-inflammatory events. Moreover, it is suggested that Z. coreanum oil and estragole may negatively control the production of SNARE proteins (VAMP7) at the tran-scriptional and translational levels in common. These results demonstrate that Z. coreanum oil and its major component, estragole, possess potent anti-inflammatory abilities that are coupled with antioxidant properties.
        4,000원
        3.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        난자의 성숙과정과 노화에 관한 이해는 인공수정과 체외수정 최적기를 판단하기 위하여 가장 중요한 연구내용으로 알려져 있다. 이러한 기작은 번식 호르몬들에 의하여 조절되는 것으로 알려져 있으나 난자 세포질 변화에 관한 내용은 잘 알려져 있지 않다. 본 연구에서는 산화질소물(nitric oxide, NO)이 난자 성숙과정에서 증가하는 것을 밝혔으며 난자의 미성숙단계(germinal vesicle stage, GV)와 난자핵막붕괴단계(germinal vesicle breakdown, GVBD) 및 성숙완료단계(metaphase II, MII)단계에서 생산되는 NO의 양을 비교하였다. 또한, 난자를 체외에서 배양할 때, MII단계로 성숙되지 않는 성장 단계의 난자에서는 NO의 증가 현상을 관찰할 수 없었고, 세포질이 불균일한 노화된 난자에서는 NO가 증가된 상태로 유지되는 특성이 있음을 밝혔다. 이러한 결과는 NO의 작용이 난자의 성숙과정과 난자 노화과정에서 중요한 기능을 담당하고 있음을 보여주고 있다.
        4,000원
        4.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Steaming is a method that has traditionally been used for medicinal plant extraction. This study investigated nitrite oxide production, ferrous ion chelating activity, α-glucosidase, xanthine oxidase, and acetylcholinesterase inhibitory activities of ethanol, acetone and hot-water extracts of Codonopsis lanceolata prepared by steaming seven times. MTT assay showed that each extract was non-toxic up to a concentration of 700 μg/mL confirming that there was no cytotoxicity in all extracts. The α-glucosidase, xanthine oxidase, and acetylcholinesterase inhibitory activities exhibited by the hot-water extract obtained from steaming seven times were higher (83.1%) than the other extracts. Higher production of nitrite oxide and better ferrous chelating activity was recorded with hot-water extract compared to ethanol and acetone extracts. These results indicated that more steaming of Codonopsis lanceolata extracts would be required to validate the possibility of developing antioxidants. Also, further study is needed to determine if the components present in the tested extracts might be useful in the prevention of Alzheimer's disease. These results showed that hot-water extracts may be useful for their antioxidant and the production inhibitory activity of nitrite oxide. It will be helpful in the investigation of the constituent analysis of the steam-processed product of Codonopsis lanceolata.
        4,000원
        5.
        2020.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Nitric oxide (NO)-induced protein S-nitrosylation triggers mitochondrial dysfunction and was related to cell senescence. However, the exact mechanism of these damages is not clear. In the present study, to investigate the relationship between in vitro aging and NO-induced protein S-nitrosylation, oocytes were treated with sodium nitroprusside dihydrate (SNP), and the resultant S-nitrosylated proteins were detected through biotin-switch assay. The results showed that levels of protein S-nitroso thiols (SNO)s and expression of S-nitrosoglutathione reductase (GSNOR) increased, while activity and function of mitochondria were impaired during oocyte aging. Addition of SNP, a NO donor, to the oocyte culture led to accelerated oocyte aging, increased mitochondrial dysfunction and damage, apoptosis, ATP deficiency, and enhanced ROS production. These results suggested that the increased NO signal during oocyte aging in vitro, accelerated oocyte degradation due to increased protein S-nitrosylation, and ROS-related redox signaling.
        4,000원
        6.
        2018.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Nitric oxide (NO) has an important role in oocyte maturation and embryonic development in mammals. This study examined the effect of exogenous NO donor S-nitroso-N-acetylpenicillamine (SNAP) in a maturation medium on meiotic progression and embryonic development after parthenogenesis (PA) and somatic cell nuclear transfer (SCNT) in pigs. When oocytes were exposed to 0.1 μM SNAP for first 22 h of in vitro maturation (IVM) in Experiment 1, SNAP significantly improved blastocyst development in both defined and standard follicular fluid-supplemented media compared to untreated control (48.4 vs. 31.7-42.5%). SNAP treatment significantly arrested meiotic progression of oocytes at the germinal vesicle stage at 11 h of IVM (61.2 vs. 38.7%). However, there was no effect on meiotic progression at 22 h of IVM (Experiment 2). In Experiment 3, when oocytes were treated with SNAP at 0.001, 0.1 and 10 μM during the first 22 h of IVM to determine a suitable concentration, 0.1 μM SNAP (54.2%) exhibited a higher blastocyst formation than 0 and 10 μM SNAP (36.6 and 36.6%, respectively). Time-dependent effect of SNAP treatment was evaluated in Experiment 4. It was observed that SNAP treatment for the first 22 h of IVM significantly increased blastocyst formation compared to no treatment (57.1% vs. 46.2%). Antioxidant effect of SNAP was compared with that of cysteine. SNAP treatment significantly improved embryonic development to the blastocyst stage (49.1-51.5% vs. 34.4-37.5%) irrespective of the presence or absence of cysteine (Experiment 5). Moreover, SNAP significantly increased glutathione (GSH) content and inversely decreased the reactive oxygen species (ROS) level and mitochondrial oxidative activity in IVM oocytes. SNAP treatment during IVM showed a stimulating effect on in vitro development of SCNT embryos (Experiment 7). These results demonstrates that SNAP improves developmental competence of PA and SCNT embryos probably by maintaining the redox homeostasis through increasing GSH content and mitochondrial quality and decreasing ROS in IVM oocytes.
        4,000원
        9.
        2017.10 구독 인증기관·개인회원 무료
        Nitiric oxide (NO) and eicosanoids function as crucial immune mediators in insects. This study focuses on cross-talkbetween two immune mediators in term of humoral immune response in Spodoptera exigua. Up-regulation of eight differentanti-microbial peptides (AMP) was observed against bacterial challenge. In contrast, injection of E. coli along with L-NAMEsignificantly down regulation the AMP production whereas D-NAME was not effective. The injection of E. coli withdexamethasone or SNAP also decreased AMP production whereas arachidonic acid (AA) compensated the dexamethasoneeffects. RNA inerferece against SeNOS showed the down-regulation of defensin mRNA level, whereas dsNOS injectionswith AA reversed the gene regulation.
        10.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Colorectal cancer is a major cause of morbidity and mortality that accounts for over 9% of all incidences of cancer. Additionally, colorectal cancer is widely recognized as an environmental disease related to ill-defined cultural, social and lifestyle factors including physical activity, obesity, cigarette smoking and heavy alcohol consumption. Accordingly, natural phytochemicals and extracts have attracted attention because of their beneficial biological effects. Coenzyme Q10 (CoQ10) is a common supplementary medicine applied to increase bioenergetic capacity in various diseases. Therefore, in this study, we investigated whether CoQ10 treatment has any inhibitory effects and its related cellular mechanisms in human colon cancer HCT116 cells. A MTT assay revealed that CoQ10 slightly decreased the proliferation of HCT116 cells; however, glutathione- and superoxide dismutase- activity were unchanged in response to CoQ10 treatment. A DCF-DA assay revealed that CoQ10 slightly increased ROS release of HCT116 cells. However, in a nitric oxide (NO) assay, CoQ10 significantly increased NO production in a dose-dependent manner. The results of western blot analysis revealed that the protein levels of Bax, p21 and p53 were increased, whereas the protein level of Bcl2 was decreased suggesting that the CoQ10-mediated inhibitory mechanism is associated with apoptotic signaling. Taken together, our findings indicate that CoQ10 has an inhibitory effect on the growth of colon cancer cells via NO production that is associated with regulation of factors involved in apoptotic signaling including Bax, Bcl2, p21 and p53.
        4,000원
        11.
        2017.04 구독 인증기관·개인회원 무료
        Nitric oxide (NO) is an immune mediator in several insects. In addition, eicosanoids mediate various immune responses in response to microbial challenges. This study focuses on cross-talk between two immune mediators. Nitric oxide synthase (SeNOS) of Spodoptera exigua was predicted in its cDNA sequence by interrogation to the transcriptomes and validated by RT-PCR against developmental stage and larval tissues. RNA interference (RNAi) of SeNOS suppressed nodule formation of S. exigua larvae against heat-killed Xenorhabdus hominickii. RNAi of SeNOS also suppressed NO levels in fat body and hemocytes along with suppression of PLA2 activity. NOS-specific inhibitor, L-NAME, also inhibited PLA2 activity, but its enantiomer, D-NAME, did not. However, PLA2 of dexamethasone or oxindole did not suppress NO levels in the immune tissues. In addition, X hominickii did not inhibit up-regulation of NO levels. These results suggest that NO signal activates PLA2 to produce eicosanoids to mediate immune responses
        12.
        2015.12 구독 인증기관 무료, 개인회원 유료
        Cariogenic Streptococcus mutans encounters a variety of host defense factors produced in oral cavity. Nitric oxide (NO) and NO-mediated reactive nitrogen species are potential antimicrobials of innate immunity that can threaten the fitness of S. mutans in their ecological niches. Streptococcal strategies to detoxify cytotoxic NO, which allow S. mutans to persist in caries or other environments of the oral cavity, remain unknown. In this study, we directly measured NO consumption rates of S. mutans isolated in Korea. Surprisingly, all S. mutans strains were unable to consume exogenous NO efficiently, while an intracellular parasite Salmonella enterica serovar Typhimurium expressing the NO-metabolizing enzyme flavohemoglobin consumed most of the NO. This result suggested that S. mutans has alternative detoxification systems for tolerating NO-induced nitrosative stresses.
        4,000원
        13.
        2015.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Russula rosacea, a mycorrhizal fungus, has been used for edible and medicinal purposes. This study was conducted to evaluate the in vitro antioxidant, anti-hyperglycemic, anti-cholinesterase, and nitric oxide inhibitory effects of the fruiting bodies from R. rosacea extracted with methanol, and hot water. The 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activities of the methanol and hot water extracts (2.0 mg/ml) of R. rosacea were comparable with BHT, the positive control. The chelating effects of the mushroom and hot water extracts were significantly higher than that of BHT. The reducing power of methanol and hot water extract (6 mg/ml) were significantly lower than that of BHT. Seven phenolic compounds were detected from acetonitrile and hydrochloric acid solvent extract of the mushroom. alpha-amylase and alpha-glucosidase inhibitory activities of methanol and hot water extracts were lower than that of acarbose, the positive control. The acetylcholinesterase and butyrylcholinesterase inhibitory effects were moderate compared with galanthamine, the standard drug. Nitric oxide (NO) production in lipopolysaccharide (LPS) induced RAW 264.7 cells were inhibited significantly by the mushroom extracts in a concentration dependent manner. Therefore, we demonstrated that fruiting bodies of R. rosacea possess in vitro antioxidant, anti-hyperglycemic, anti-cholinesterase, and NO production inhibitory activities. The experimental results suggest that the fruiting bodies of R. rosacea are good natural antioxidant, anti-hyperglycemic, anti-cholinesterase, and anti-inflammatory sources.
        4,000원
        14.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        저온은 식물 생장을 저해하는 주된 요인이며 병원균에 대한 감수성을 증가시킨다. 그러므로 식물체에서 스트레스 내성을 증대시키는 것은 불리한 환경 조건에서 살아 남기 위한 중요한 전략이다. 본 실험의 목적은 고추 묘에서 저온 내성과 식물병 발생에 대한 외생 살리실산(SA)과 일산화질소(NO) 처리의 효과를 밝히는 것이다. 정식 후 23일 동안 고추 묘(Capsicum annuum L. ‘기대만발’)는 온도 20/25oC(낮/밤), 광주기 15시간, 광도 145±5μmol·m−2·s−1 의 정상적인 생육환경에서 자랐다. 1주일에 2번 계면활성 제 0.1%를 포함한 SA와 NO 3mL을 고추 묘에 각각 분사 해주었다. 처리 후 고추 묘는 암 상태에서 6시간 동안 4oC 저온에 노출시킨 후 정상적인 생육환경에서 2일 동안 회복시켜주었다. 저온 스트레스에 대한 식물 내성을 평가 하기 위해 저온 처리 후 생육특성, 엽록소 형광 값, 세포 막 투과성을 측정하였다. 총 페놀릭 농도와 항산화도는 실험하는 동안 측정하였다. 또한, 고추의 점무늬병과 풋마름 병 발생 정도도 조사하였다. 저온 처리 전·후를 비교하여 대조구 고추묘에서는 저온에 의해 상대적으로 많은 수분을 손실하여 건물율이 높지만 SA와 NO 처리 된 고추 묘는 비슷한 건물율을 유지하였다. 저온 처리 후 대조구에 비해 SA와 NO 처리구의 전해질 유출 값은 더 낮았다. 저온 처리 동안 SA와 NO 처리구의 엽록소 형광값은 약 0.8 수준으로 유지하였지만 대조구는 빠르게 감소하였다. 화학적 처리 동안 SA 처리구의 총 페놀릭 농도와 항산화도는 NO 처리구보다 높았다. 또한 저온 처리 후 대조구와 NO 처리구의 총 페놀릭 농도는 증가하였다. 고추에서 풋마름병에 대한 저항성은 SA가 보다 효과적이었다. 본 실험의 결과는 SA와 NO의 외생처리는 고추 묘의 저온 내성을 증대시켰고 병 발생 정도를 감소시키는 데 효과적이었음을 보여준다.
        4,000원
        15.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 메탄올과 열수를 이용해 갈색먹물버섯의 자실체로부터 추출한 물질의 항산화, 항당뇨, 항콜린에스 테라아제, 항티로시나제와 항염증 효과를 탐색하 였다. 고 속액체크로마토그래피를 이용해 추출물의 페놀성 화합물 을 분석한 결과 procatechuic acid, chlorogenic acid, (-)- epicatechin, naringin 등 총 4종류의 페놀성 화합물이 확 인되었다. 항산화 효과 실험에서 DPPH radical 소거능은 양성대조군으로 사용한 BHT에 비해 낮았지만 효과가 비 교적 우수하였고, 철 이온을 제거하는 항산화 효과는 메 탄올과 열수 추출물이 양성대조군인 BHT에 비해 30% 높게 나타났으나 환원력은 양성대조군에 비해 43% 정도 낮은 것으로 나타났다. 항당뇨 실험에서 α-amylase와 α- glucosidase에 대한 메탄올과 열수추출물의 저해효과는 2.0 mg/ml의 농도에서 각각 62.26%와 67.59%를 보여 양 성대조군인 acarbose의 81.81%에 비해 낮았다. 아세틸콜 린에스테라아제에 대한 메탄올과 열수추출물의 저해효과 는 1.0 mg/ml의 농도에서 각각 94.64%와 74.19%를 보여 양성대조군인 galanthamine의 97.80%에 비해 낮았다. 티 로시나아제에 대한 메탄올과 열수추출물의 저해효과는 2.0 mg/ml의 농도에서 각각 91.33%와 91.99%를 나타내 양성대조군인 kojic acid의 99.61%와 매우 유사한 효과를 얻었다. 염증저해 효과 실험에서는 RAW 264.7 대식세포 가 배양되고 있는 배지에 갈색먹물버섯 자실체의 메탄올 과 열수추출물을 각각 전 처리 한 후 염증매개 물질인 LPS를 투여하여 메탄올과 열수 추출물의 NO 생성 저해 효과를 조사한 결과 추출물의 농도가 증가함에 따라 생성 된 NO의 양이 감소하는 경향을 나타내었다. 따라서 갈색 먹물버섯의 자실체에는 항산화, 항당뇨, 항아세틸콜린에 스터라제 항티로시나아제 및 항염증 효과를 나타내는 물 질이 함유되어 있어서 천연 건강식품으로 이용이 가능할 것으로 사료된다.
        4,200원
        16.
        2013.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We present an easy method of preparing two-dimensional (2D) periodic hollow tin oxide (SnO2) hemisphere array gas sensors using polystyrene (PS) spheres as a template. The structures were fabricated by the sputter deposition of thin tin (Sn) metal over an array of PS spheres on a planar substrate followed by calcination at an elevated temperature to oxidize Sn to SnO2 while removing the PS template cores. The SnO2 hemisphere array structures were examined by scanning electron microscopy and X-ray diffraction. The structures were calcined at various temperatures and their sensing properties were examined with varying operation temperatures and concentrations of nitric oxide (NO) gas. Their gas-sensing properties were investigated by measuring the electrical resistances in air and the target gases. The measurements were conducted at different NO concentrations and substrate temperatures. A minimum detection limit of 30 ppb, showing a sensitivity of S = 1.6, was observed for NO gas at an operation temperature of 150˚C for a sample having an Sn metal layer thickness corresponding to 30 sec sputtering time and calcined at 600˚C for 2 hr in air. We proved that high porosity in a hollow SnO2 hemisphere structure allows easy diffusion of the target gas molecules. The results confirm that a 2D hollow SnO2 hemisphere array structure of micronmeter sizes can be a good structural morphology for high sensitivity gas sensors.
        4,000원
        17.
        2011.12 구독 인증기관 무료, 개인회원 유료
        These study was carried out to investigate the effects of the supplementation with sodium nitroprusside (SN) and nitric oxide (NO) of canine oocytes on IVM rates. Oocytes were incubated in TCM-199 supplement with at 0.03~0.10 mM SN and 0.3~1.0 mM NO for 48 hrs. Oocytes were transferred to 50 ul drops of maturation medium covered mineral oil and cultured in a CO2 incubator (5% CO2, 95% air, 38℃). The in vitro maturation rate of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.03, 0.05, 0.07, 0.10 mM SN were 25.9±3.5%, 36.4±3.2%, 33.3±3.5%, 28.8±3.2%, respectively. The in vitro maturation rate of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.03~0.07 mM SN were significantly increased compare to the control (26.0±2.2%). The in vitro maturation rates of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.3, 0.5, 0.7, 1.0 mM NO were 28.0±4.2%, 36.5± 3.6%, 30.0±3.8%, 19.2±3.5%, respectively. The in vitro maturation rate of oocytes in TCM-199 medium supplemented with 0.3 and 0.5 mM NO were significantly increased compare to the control (26.0±2.2%). The in vitro maturation rates of oocytes cultured for 12~48 hrs in TCM-199 medium supplement with 0.05 mM SN were 26.0±3.2%, 28.0±3.4%, 38.0±3.2%, respectively. The in vitro maturation rate of oocytes cultured for 12~48 hrs in TCM-199 medium supplement with 0.5 mM NO were 22.0±3.0%, 30.0±3.8%, 36.0±4.2%, respectively. These result was significantly increased compare to the control.
        4,000원
        18.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
         ,  , Cordyceps (vegetable wasp and plant worm), an entomopathogenic fungi, has been used as a herbal medicine in Asian countries since ancient times. Cordyceps nutans is common but there is little research on this species. This study investigated the optimal culture conditions of C. nutans and the inhibitory effect on nitric oxide (NO) production in RAW 264.7 cell treated culture broth. The optimal conditions for the mycelial growth were 25℃ and pH 7.0-8.0. Mycelial growth was highest on mushroom complete medium (MCM), V8 juice agar (V8A), and yeast malt dextrose (YMD) medium. Mycelial growth on mushroom minimal medium (MMM) did not occur, so nutrient source was essential. Dextrose and sucrose as carbon sources, and ammonium citrate as a nitrogen source were satisfactory for mycelial growth. Cytotoxicity of C. nutans culture broth was not found in RAW 264.7 cells. C. nutans culture broth suppressed NO production of lipopolysaccharide (LPS)-stimulated RAW 264.7 cell in a dose-dependent manner. Thus, our results provided the optimal conditions for cultivation of C. nutans and showed that C. nutans may have excellent physiological activities.
        4,000원
        20.
        2009.03 구독 인증기관 무료, 개인회원 유료
        The purpose of the present study was to examine the role of peripheral nitric oxide (NO) pathways in the onset of interleukin (IL)-1β-induced mechanical allodynia in the orofacial area. Experiments were carried out on male Sprague-Dawley rats weighing 230-280 gm and surgical procedures were performed under pentobarbital sodium (40 mg/kg, i.p.). Under anesthesia, a polyethylene tube (PE10) was implanted into the subcutaneous area of one vibrissa pad, which enabled the injection of IL-1β or other chemicals. We subcutaneously injected 50 μL of IL-1β into a vibrissa pad through the implanted polyethylene tube with a 100 Hamilton syringe. After the administration of 0.01, 0.1, 1, or 10 pg of IL-1β, withdrawal behavioral responses were examined. The subcutaneous injection of saline had no effects on the air-puff thresholds. Following the subcutaneous injection of 0.01, 0.1, 1, or 10 pg of IL-1, the threshold of air puffs decreased significantly to 12± 3, 7 ± 2, 5 ±1, or 5 ± 1 psi, respectively, in a dose dependent manner. Pretreatment with L-NAME, a nitric oxide synthase (NOS) inhibitor, blocked IL-1β-induced mechanical allodynia. However, neither D-NAME, an inactive isomer of L-NAME, nor vehicle affected the IL-1β-induced mechanical allodynia. Subcutaneous injection of IL-1 increased the number of c-fos-like immunoreactive neurons, whereas pretreatment with L-NAME decreased this number, in the trigeminal caudal nucleus. These results suggest that pro-inflammatory cytokines and NO are important contributors to the pathogenesis of persistent and exaggerated IL-1β-induced pain states. Based on these observations, peripheral application of NOS inhibitors may be of therapeutic value in treating pain disorders in the clinic.
        4,000원
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