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        검색결과 257

        41.
        2019.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 CMB(Chemical Mass Balance) 모델을 이용하여 PM2.5에 대한 오염원 확인 및 오염원별 기여도를 분석하였다. A시의 배출원별 기여도 순위는 비산먼지(30.1%) > 생물성 연소(21.9%) > 2차 오염물질(21.1%) > 도로이동오염원(19.3%) > 면오염원(7.6%) 순이고, CMB 모델 기여도와 CAPSS(Clean Air Policy Support System) 배출자료 기여도 비교에서 증가한 배출원은 생물성 연소와 2차 오염물질이고, 감소한 배출원은 도로이동오염원, 비산먼지, 면오염원으로 분석되었다.
        4,000원
        42.
        2019.06 구독 인증기관 무료, 개인회원 유료
        Xylitol is well-known to have an anti-caries effect by inhibiting the replication of cariogenic bacteria. In addition, xylitol enhances saliva secretion. However, the precise molecular mechanism of xylitol on saliva secretion is yet to be elucidated. Thus, in this study, we aimed to investigate the stimulatory effect of xylitol on saliva secretion and to further evaluate the involvement of xylitol in muscarinic type 3 receptor (M3R) signaling. For determining these effects, we measured the saliva flow rate following xylitol treatment in healthy individuals and patients with dry mouth. We further tested the effects of xylitol on M3R signaling in human salivary gland (HSG) cells using realtime quantitative reverse-transcriptase polymerase chain reaction, immunoblotting, and immunostaining. Xylitol candy significantly increased the salivary flow rate and intracellular calcium release in HSG cells via the M3R signaling pathway. In addition, the expressions of M3R and aquaporin 5 were induced by xylitol treatment. Lastly, we investigated the distribution of M3R and aquaporin 5 in HSG cells. Xylitol was found to activate M3R, thereby inducing increases in Ca2+ concentration. Stimulation of the muscarinic receptor induced by xylitol activated the internalization of M3R and subsequent trafficking of aquaporin 5. Taken together, these findings suggest a molecular mechanism for secretory effects of xylitol on salivary epithelial cells.
        4,000원
        43.
        2019.06 구독 인증기관 무료, 개인회원 유료
        Melatonin is a neurotransmitter that modulates various physiological phenomena including regulation and maintenance of the circadian rhythm. Nicotinic acetylcholine receptors (nAChRs) play an important role in oral functions including orofacial muscle contraction, salivary secretion, and tooth development. However, knowledge regarding physiological crosstalk between melatonin and nAChRs is limited. In the present study, the melatoninmediated modulation of nAChR functions using bovine adrenal chromaffin cells, a representative model for the study of nAChRs, was investigated. Melatonin inhibited the nicotinic agonist dimethylphenylpiperazinium (DMPP) iodide-induced cytosolic free Ca2+ concentration ([Ca2+]i) increase and norepinephrine secretion in a concentrationdependent manner. The inhibitory effect of melatonin on the DMPP-induced [Ca2+]i increase was observed when the melatonin treatment was performed simultaneously with DMPP. The results indicate that melatonin inhibits nAChR functions in both peripheral and central nervous systems.
        4,000원
        44.
        2019.04 구독 인증기관·개인회원 무료
        In moth, pheromone biosynthesis activating neuropeptide (PBAN) regulates pheromone biosynthesis by binding to its receptor (PBANr). In this study, we cloned a PBANr gene (Mvi-PBANr) from sex pheromone gland in M. vitrata, which encodes 475 amino acid and includes 7 transmembrane domains. As a results of phylogenetic analysis, Mvi-PBANr is clustered with lepidopteran PBANrs. Mvi-PBANr was investigated for the effect of pheromone biosynthesis via RNA interference (RNAi), gas chromatography (GC) and bioassay. Consequently, expression level of Mvi-PBANr suppressed via RNAi, resulting in decrease pheromone component (E10E12-16:Ald). Mating rate was also reduced when performing the RNAi. These results revealed that Mvi-PBANr played important role in the pheromone biosynthesis in M. vitrata, and Mvi-PBANr can be used as new pest control targets.
        45.
        2019.04 구독 인증기관·개인회원 무료
        A specific serotonin receptor (Se-5HTR) has been identified in the beet armyworm, Spodoptera exigua and classified into 5-HT7 type. Se-5HTR expression was up-regulated in hemocytes and fat body in response to immune challenge. As being a GPCR, this receptor is presumably coupled with intracellular trimeric Gαs protein activating cAMP-dependent protein kinase (PKA) pathway to regulate several cellular functions. RNA interference (RNAi) of Se-5HTR as well as its downstream signal proteins exhibited significant suppression in cellular immune responses including nodulation and phagocytosis. Application of inhibitors to the signaling cascade suppressed the immune responses as well. To validate the Se-5HTR involvement in mediating cellular immunity, 5-HTR knock-out mutants were developed using CRISPR-Cas9 technique and suffered significant developmental anomalies.
        46.
        2019.04 구독 인증기관·개인회원 무료
        최근 파밤나방 등 다양한 나비목 해충에서 diamide 계통의 살충제 (IRAC group 28)의 저항성이 많이 보고가 되고 있다. 국내에서도 이미 배추좀나방과 파밤나방의 저항성이 보고되었는데, 본 연구에서 사용된 강릉에서 2018년 채집한 파밤나방의 경우 Chlorantraniliprole에 대하여 감수성 대비 2,500배 이상의 높은 저항성을 나타냈다. 추천 농도 처리 시 30% 이하의 방제가를 나타냈으며 Cyantraniliprole, Cyclaniliprole, Flubendiamide에서 높은 교차저항성을 나타냈다. 이 저항성 집단에서 diamide 계통 살충제의 작용점인 ryanodine receptor에 이미 보고된 G4946E 돌연변이는 발견되지 않았으나 새로운 I4760M 돌연변이를 발견하였는데, 2014년 배추좀나방에서 보고된 돌연변이와 위치가 동일하였다. 따라서 I4760M 돌연변이는 파밤나방에서 diamide 저항성에 관여 할 것으로 판단한다.
        48.
        2018.11 구독 인증기관·개인회원 무료
        Prolactin is an anterior pituitary hormone involved in various physiological phenomenon including reproduction. The prolactin receptor (PRLR) is detected in diverse tissues such as brain, ovary, placenta and uterus in several mammalian species. A total of 227 pigs [Korean native pigs (KNP) 27; Landrace pigs 29; Korean native pigs x Landrace F1 91; Nanchuckmacdon pigs 80] were used to investigate the allele frequency difference of the prolactin receptor (PRLR) gene among the four pig lines. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with Alu I restriction enzyme was used to determine the genotypes of PRLR. Frequencies of PRLR alleles among the four different pig lines were not significantly different (Chi-square=3.94, DF=3, P=0.27). A total of 40 Nanchuckmacdon pigs were used to investigate the effect of the prolactin receptor (PRLR) gene on total number of piglets born (TNB), number of piglets of alive (NBA) using general linear model implemented in MINITAB software. For TNB, the AB genotype had higher genotypic value (10.61) than the values of AA (9.83) and BB (10.30). Likewise, the AB genotype had higher genotypic value (8.96) than the values of AA (8.18) and BB (8.90) for NBA. However, these associations of the PRLR gene with TNB and NBA were not statistically significant. In conclusion, it is necessary to increase the sample size for investigating the effect of the PRLR gene on TNB and NBA in pigs.
        49.
        2018.10 구독 인증기관·개인회원 무료
        붉은불개미는 남미가 원산인 외래해충으로써 기후변화로 인한 기온 상승과 국가간 교역량의 증가를 통해 전세계적으로 서식범위를 확장해 나가고 있다. 국내에서는 붉은불개미가 2017년 9월 부산 감만항에서 처음 발견된 이후 올해까지 4차례 추가로 발견되어 국내 침입 및 정착 가능성이 점차 증가하고 있다. 곤충에서 인슐린 신호체계는 일반적으로 산란, 생장 및 발육, 대사계, 스트레스 저항성에 관여하는 것으로 널리 알려져 있다. 본 연구에서는 붉은불개미의 인슐린에 대한 생물학적인 기능을 이해하기 위해 인슐린 수용체(insulin receptor)의 발현을 억제한 후 나타나는 생리적 변화를 관찰하였다. 그 결과 체내빙결점(supercooling point)에 영향을 미쳐 붉은불개미의 저온생리에 영향을 준다는 것을 확인할 수 있었다.
        53.
        2018.03 구독 인증기관 무료, 개인회원 유료
        In this study, we analyzed signal transduction by equine follicle-stimulating hormone receptor (eFSHR) on stimulation with recombinant eelFSHβ/α (rec-eelFSHβ/α), natural porcine FSH (pFSH), and natural human FSH (hFSH). cAMP stimulation in CHO-K1 cells expressing eFSHR was determined upon exposure to different doses (0-1450 ng/mL) of these hormones. The EC50 value of rec-eelFSHβ/α was 53.35 ng/mL. The Rmax values of rec-eelFSHβ/α and pFSH were 28.12 and 2.88 ng/mL, respectively. The activity of rec-eelFSHβ/α was much higher than that of natural pFSH. However, signal transduction in CHO PathHunter Parental cells expressing eFSHR was not enhanced by stimulation with natural hFSH. Thus, rec-eelFSHβ/α was completely active in cells expressing eFSHR. However, natural hFSH did not invoke a signal response in cells expressing eFSHR. Particularly, natural pFSH was weakly active in the same cells. These results showed that eelFSHβ/α has potent activity in cells expressing eFSHR. Thus, rec-eelFSHβ/α may efficiently bind to eFSHR, where as natural hFSH does not bind to eFSHR.
        4,000원
        54.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        There is a growing demand for natural sleep aids due to various side effects of long-term administration of pharmacological treatments for insomnia. Honey has been reported to exhibit numerous potential health benefits, and it is hypothesized that honey may favorably affect insomnia treatment. Therefore, this study was performed to investigate the possible hypnotic effect of clover honey (CH) and to determine its in vivo mechanism. The total flavonoid content (TFC) of CH and fractions extracted with ethylacetate (EtOAc) and H2O was measured. The pentobarbital-induced sleep test using GABAA-benzodiazepine (BZD) agonists and antagonists was conducted to evaluate the potential mechanism of action behind the sedative-hypnotic activity of CH in mice. The results showed that administration of 500 and 1,000 mg/kg of CH significantly (p<0.01) reduced the sleep latency to a level similar to that of diazepam (DZP, 2 mg/kg), and 1,000 mg/kg of CH significantly (p<0.01) prolonged the sleep duration, which was comparable to that of DZP (2 mg/kg). Administration of the EtOAc fraction with a higher TFC significantly reduced the sleep latency at 50 to 200 mg/kg and prolonged the sleep duration at 100 to 200 mg/kg, which were comparable to those after administration of DZP (2 mg/kg). However, co-administration of CH and EtOAc with flumazenil, a specific GABAA-BZD receptor antagonist, blocked the hypnotic effect. Our findings suggest that the hypnotic activity of CH may be attributed to allosteric modulation of GABAA-BZD receptors. The TFC of CH is expected to be a key factor that contributes to its hypnotic effect.
        4,000원
        55.
        2017.12 구독 인증기관 무료, 개인회원 유료
        Transient receptor potential melastatin 8 (TRPM8) plays a crucial role in innocuous cool sensation, acute cold pain and cold-induced hyperalgesia during pathologic conditions. To help understand TRPM8-mediated cold perception in the dental pulp and periodontal tissues, we examined the distribution of TRPM8-immunopositive (+) axons in molar and incisor pulp and periodontal tissues using transgenic mice expressing a genetically encoded axonal tracer in TRPM8+ neurons. In the radicular pulp of the molar teeth, a small number of TRPM8+ axons were observed. TRPM8+ axons branched frequently and extensively in the core of coronal pulp, forming a network in the peripheral pulp. Some TRPM8+ axons ascended between odontoblasts and were observed in the dentinal tubule. TRPM8+ axons were linear-shaped in the radicular pulp, whereas many TRPM8+ axons showed portions shaped like beads connected with thin axonal stands at the peripheral pulp. TRPM8 was densely expressed in the bead portions. In the incisor pulp, TRPM8+ axons were occasionally observed in the core of the coronal pulp and rarely observed at the peripheral pulp. TRPM8+ axons were occasionally observed and showed a linear shape rather than a bead-like appearance in the periodontal ligament and lamina propria of the gingival tissue. These findings, showing differential distribution of TRPM8+ axons between radicular and coronal portions of the molar pulp, between incisor and molar pulp, and between dental pulp and periodontal tissues, may reflect differential cold sensitivity in these regions.
        4,000원
        57.
        2017.10 구독 인증기관 무료, 개인회원 유료
        IL-1RAcP는 일명 interleukin-1 receptor accessory protein이라 칭하며 interleukin-1 염증성 사이 토카인과 interleukin-1 receptor I (IL-1RI) 결합체와 복합체를 형성하여 작용한다. IL-1RAcP는 면 역반응, 스트레스 및 세포사멸과 관련이 있다. 본 연구의 목적은 참돔(Pagrus major)을 저수온 (8℃, 33 psu) 및 저염분(20℃, 10 psu) 상태에 노출시킨 후, IL-1RAcP 유전자의 발현을 관찰하는 것이다. 연구결과, IL-1RAcP 유전자의 발현은 저수온(8℃, 33 psu) 및 저염분(20℃, 10 psu) 상태 에서 유의적으로 증가하는 것으로 나타났다. 이 연구결과로서 IL-1RAcP 유전자는 저수온 및 저 염분 등의 환경 스트레스에 대한 생체지표유전자로서 역할을 한다고 제의한다.
        4,000원
        58.
        2017.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was performed to investigate the body fat-lowering effect of garlic powder in peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α)-luciferase transgenic mice (TG). In this study, we generated transgenic mice with a PGC-1α promoter (—970/+412 bp) containing luciferase as a reporter gene. Mice were fed a 45% high-fat diet for 8 weeks to induce obesity. Subsequently, mice were maintained on either a high-fat control diet (CON), or high-fat diets supplemented with 2% (GP2) or 5% (GP5) garlic powder for an additional 8 weeks. Dietary garlic powder reduced the body weight in the GP2 and GP5 groups, compared to the CON group. Furthermore, garlic supplementation significantly decreased the plasma levels of triglycerides, total cholesterol, and leptin in the GP5 group, compared to the CON group. Specifically, luciferase activity in liver, white adipose tissue (WAT), and brown adipose tissue (BAT) was increased by garlic supplementation in a dose-dependent manner. These results suggest that the body fat-lowering effect of garlic powder might be related to PGC-1α by the increase in luciferase activity in liver, WAT, and BAT. Furthermore, transgenic mice might be useful for evaluating the body fat-lowering effect of various health functional foods.
        4,000원
        59.
        2017.10 구독 인증기관·개인회원 무료
        Recently, it has been reported that plants produce variety of phytochemicals against insect pests as a part of their defencemechanism. In this study, to identify novel compounds that disrupt juvenile hormone (JH) receptor complex, plant essentialoil compounds were tested using in vitro yeast two-hybrid system transformed with the Aedes aegypti JH receptor complex.Among the plant essential oil compounds, farnesol interfered with pyriproxyfen-mediated binding of A. aegypti Met-FISC.In contrast, farnesyl acetate induced the binding of A. aegypti Met-FISC. Also, both compounds caused retardation ofovarian development and change of transcription level in female A. albopictus. These results could provide insights onthe plant-insect coevolution and may be useful for the development of insect specific and safe pesticides.
        60.
        2017.04 구독 인증기관·개인회원 무료
        Insect growth regulators (IGRs) are insecticides that disrupt the normal development of target insects by inducing symptoms such as premature molting or supernumerary larval stages. Juvenile hormone (JH)-based IGRs are of particular interest because they simulate or interfere with the formation of juvenile hormone receptor complex. Insect larvae generally have been poorly susceptible to JH agonists (JHAs) because endogenous JH titer is already high in the larval stage. In contrast, JH antagonists (JHANs) might be more effective for control of target pests in larval stages through interference in the status quo action of JHs. In this study, we tested 2,354 chemical compounds using the yeast-two hybrid system to identify JHANs. Among them, K265674 sample was selected and its insecticidal activity was evaluated against Aedes albopictus larvae. These results may be useful for development of novel IGR insecticide.
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