http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
불소적용시 법랑질과 상아질에서 불화칼슘형성의 차이에 관한 실험적 연구
김재곤,권선자,윤현두,안수현,백병주 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.1
The purpose of this study was to compare the amount of calcium fluoride deposited on the enamel and dentin surface and to obtain information on the morphological change and crystallographic details of mineral deposition after 12,000ppm APF application in vitro. The bovine enamel and dentin blocks were randomly assigned to eight groups according to artificial caries lesion formation and difference of fluoride application time. The fluoride concentration and morphological characteristics on the treated enamel and dentin surface were investigated by using fluoride quantitative analysis and SEM. The powdered enamel and dentin of the intact bovine incisors were prepared for the X-ray diffraction analysis. The following results were obtained. 1. The amounts of KOH-soluble fluoride on the carious enamel and dentin surface after 24h APF application were higher than after only 5min APF application(P<0.05), but in the case of the sound enamel and dentin surface were similar after 5min and 24h application (P>0.05). The fluoride content was highly increased in the carious dentin as compared with sound dentin after APF application(P<0.05). 2. The caruous enamel surface after APF application, the demineralized enamel surface were recovered a more dense enamel surface and precipitation of crystal was observed a distintive surface layer of spherical globules of about 1 m diameter. In the case of the fluorided carious dentin surface, precipitation of calcium fluoride-like material was deposited both inside the dentinal tubules as well as in the intertubular regions. 3. The crystallographic structure of powdered enamel and dentin after 24h APF application had large crystallities of apatite and CaF2 diffraction peaks in the enamel as compared with dentin. The diffraction data collected from the 27.50-29.50(2) angular range of the powdered enamel, the (105) apatite, (225) apatite and (111) CaF2 peaks of the enamel crystallities were detected after 24h APF application.
Role of Dopamine D2 receptor in Regulation of Hypothalamic Leptin Signaling
Baik, Ja-Hyun 이화여자대학교 세포신호전달연구센터 2008 고사리 세포신호전달 심포지움 Vol. No.10
Dopamine D2 receptor(D2R) plays a critical role in diverse neurophysiological functions in dopaminergic neurotransmission. D2R knock-out mice(D2R-/-) present a lean phenotype with a decreased in food intake, reduced body weight and fat mass, and an increase in the basal energy expenditure level as compared to their wild type(WT) littermates. D2R-/- mice displayed an improved leptin sensitivity and we observed that the administration of leptin induced an increased phosphorylation of hypothalamic signal transducer and activator of transcription 3(STAT3) in D2R-/- mice compared to WT mice, suggesting an enhanced leptin signaling in the absence of D2R. Using double immunofluorescence histochemistry, we demonstrated that D2Rs are present in leptin-sensitive STAT3-positive cells in arcuate nucleus of the hypothalamus. Furthermore, quinpirole, a dopamine D2R agonist, treatment was shown to elicit a decrease in the number of STAT3-positive neurons in response to leptin administration, in the hypothalamus of WT mice. However, this regulation was not detected in the D2R-/- mice. A reporter gene assay using the STAT3-responsive element linked to the luciferase reporter gene indicated that the stimulation of D2R results in the suppression of the leptin-induced reporter gene. Our findings suggest that dopamine D2R inhibits hypothalamic leptin signaling and that D2R may be a critical mediator of hypothalamic leptin system to regulate food intake and energy homeostasis.
Invited Mini Review : Dopamine signaling in food addiction: role of dopamine D2 receptors
( Ja Hyun Baik ) 생화학분자생물학회(구 한국생화학분자생물학회) 2013 BMB Reports Vol.46 No.11
Dopamine (DA) regulates emotional and motivational behavior through the mesolimbic dopaminergic pathway. Changes in DA signaling in mesolimbic neurotransmission are widely believed to modify reward-related behaviors and are therefore closely associated with drug addiction. Recent evidence now suggests that as with drug addiction, obesity with compulsive eating behaviors involves reward circuitry of the brain, particularly the circuitry involving dopaminergic neural substrates. Increasing amounts of data from human imaging studies, together with genetic analysis, have demonstrated that obese people and drug addicts tend to show altered expression of DA D2 receptors in specific brain areas, and that similar brain areas are activated by food-related and drug-related cues. This review focuses on the functions of the DA system, with specific focus on the physiological interpretation and the role of DA D2 receptor signaling in food addiction. [BMB Reports 2013; 46(11): 519-526]