• The Korean Journal of Physiology and Pharmacology
• /
• v.8 no.3
• /
• pp.117-127
• /
• 2004

The heterodimeric amino acid transporter family is a subfamily of SLC7 solute transporter family which includes 14-transmembrane cationic amino acid transporters and 12-transmembrane heterodimeric amino acid transporters. The members of heterodimeric amino acid transporter family are linked via a disulfide bond to single membrane spanning glycoproteins such as 4F2hc (4F2 heavy chain) and rBAT $(related\;to\;b^0,\;^+-amino\;acid\;transporter)$. Six members are associated with 4F2hc and one is linked to rBAT. Two additional members were identified as ones associated with unknown heavy chains. The members of heterodimeric amino acid transporter family exhibit diverse substrate selectivity and are expressed in variety of tissues. They play variety of physiological roles including epithelial transport of amino acids as well as the roles to provide cells in general with amino acids for cellular nutrition. The dysfunction or hyperfunction of the members of the heterodimeric amino acid transporter family are involved in some diseases and pathologic conditions. The genetic defects of the renal and intestinal transporters $b^{0,+}AT/BAT1\;(b^{0,+}-type\;amino\;acid\;transporter/b^{0,+}-type\;amino\;acid\;transporter\;1)$ and $y^+LAT1\;(y^+L-type\;amino\;acid\;transporter\;1)$ result in the amino aciduria with sever clinical symptoms such as cystinuria and lysin uric protein intolerance, respectively. LAT1 is proposed to be involved in the progression of malignant tumor. xCT (x-C-type transporter) functions to protect cells against oxidative stress, while its over-function may be damaging neurons leading to the exacerbation of brain damage after brain ischemia. Because of broad substrate selectivity, system L transporters such as LAT1 transport amino acid-related compounds including L-Dopa and function as a drug transporter. System L also interacts with some environmental toxins with amino acid-related structure such as cysteine-conjugated methylmercury. Therefore, these transporter would be candidates for drug targets based on new therapeutic strategies.

• The Korean Journal of Physiology and Pharmacology
• /
• v.4 no.5
• /
• pp.409-415
• /
• 2000

Fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) was used to evaluate the effects of dopamine HCl on the range of the rotatioanl mobility of bulk bilayer structure of the synaptosomal plasma membrane vesicles (SPMV) isolated from whole bovine brain. In a dose-dependent manner, dopamine decreased the anisotropy $({\gamma}),$ limiting anisotropy $({\gamma}{infty})$ and order parameter (S) of DPH in the membranes. These indicate that dopamine increased the rotational mobility of the probe in the neuronal membranes. Cationic 1-[4-(trimethylammonio)-phenyl]-6-phenylhexa-1,3,5-hexatriene (TMA-DPH) and anionic 3-[p-(6-phenyl)-1,3,5-hexatrienyl]-phenylpropionic acid (PRO-DPH) were utilized to examine the range of transbilayer asymmetric rotational mobility of the neuronal membranes. Dopamine had a greater increasing effect on the mobility of the inner monolayer as compared to the outer monolayer of the neuronal membranes. It has been proven that dopamine exhibits a selective rather than nonselective fluidizing effect within the transbilayer domains of the SPMV.

• KIPS Transactions on Software and Data Engineering
• /
• v.3 no.8
• /
• pp.299-308
• /
• 2014

Various literatures related computing of information processing have been recently shown the researches inspired from the remarkably excellent human capabilities which recognize and categorize very complex visual patterns such as body motions and facial expressions. Applied from human's outstanding ability of perception, the classification function of visual sequences without context information is specially crucial task for computer vision to understand both the coding and the retrieval of spatio-temporal patterns. This paper presents a biological process based action recognition model of computer vision, which is inspired from visual information processing of human brain for action recognition of visual sequences. Proposed model employs the structure of neural fields of bio-inspired visual perception on detecting motion sequences and discriminating visual patterns in human brain. Experimental results show that proposed recognition model takes not only into account several biological properties of visual information processing, but also is tolerant of time-warping. Furthermore, the model allows robust temporal evolution of classification compared to researches of action recognition. Presented model contributes to implement bio-inspired visual processing system such as intelligent robot agent, etc.

• Journal of Acupuncture Research
• /
• v.20 no.4
• /
• pp.66-84
• /
• 2003

Objectve : Recent stuides suggested that there is a strong correlation between acupuncture stimulation and its cortical activation. Another study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture. Methods : 1) Subjects and paradigms: Two separate stimulation paradigms were performed in this study. To see the effects of electro-acupuncture stimulation on K7(Fuliu), the experiment was carried out on six healthy volunteers, using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right K7(Fuliu), 2 Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. During the intervals while there was no electro-stimulation, the subjects performed motor task as a reference. The image analysis including motion correction, talairach transformation, and smoothing was done using SPM99. Results: The electro-acupuncture stimulation on K7(Fuliu) activated Brodmann's Areas of 9, 19, 23, 24, 31, 32, 39 which may be the central pathways of the electro-acupuncture stimulation on K7(Fuliu) and those brain areas may be related with the function of the electro-acupuncture stimulation on K7(Fuliu).

• Korean Journal of Biological Psychiatry
• /
• v.19 no.2
• /
• pp.77-83
• /
• 2012

Objectives : Although there have been studies that examine sex differences of the brain structures using magnetic resonance imaging, studies that specifically investigate cerebellar structural differences between men and women are scarce. The purpose of current study was to examine sex differences in structures of the cerebellum using cerebellar template and cerebellum analysis methods. Methods : Sixteen men and twenty women were included in the study. A MATLAB based program (MathWorks, Natick, MA, USA), Statistical Parametric Mapping 5 (SPM5) using the spatially unbiased infra-tentorial atlas template (SUIT) as the cerebellum template, was used to analyze the brain imaging data. Results : There was no significant difference in age between men (mean age=28.1) and women (mean age=27.2). Men showed higher gray matter density than women in two left cerebellar areas including the clusters in the lobules IV and V (a cluster located across the lobules IV and V), and the lobule VIIIb (lobules IV and V, t=4.75, p<0.001 ; lobule VIIIb, t=3.08, p=0.004). Conclusions : The current study found differences in cerebellar gray matter density between men and women. The current study holds its significance for applying the template specifically developed for the analysis of cerebellum.

• Anxiety and mood
• /
• v.16 no.2
• /
• pp.106-112
• /
• 2020

Objective : Social anxiety disorder (SAD) is characterized by fear of social threat and exhibits limbic hyper-reactivity toward social stimuli such as emotional faces. A previous study identified the uncinate fasciculus (UF) sub-tract as particularly related to facial memory. To explore the white matter tract relating to face-specific brain regions, we investigated the UF sub-tract in SAD. Methods : The diffusion tensor images of 22 patients with SAD and 20 healthy controls were analyzed with tractography. The UF sub-tract was delineated using the regions of interest of face patches in the anterior temporal lobe and the orbitofrontal cortex, and fractional anisotrophy (FA) and total number of streamlines (ST) were analyzed. We examined the group comparison of FA and ST of the UF sub-tract and correlations of FA and ST with the social anxiety symptoms such as the Liebowitz Social Anxiety Scale (LSAS), the Social Interaction Anxiety Scale (SIAS), the Social Phobia Scale (SPS) and the Fear of Negative Evaluation scale (FNE) in SAD. Results : There were no group differences in FA and ST of the UF sub-tract. However, negative correlations were observed between ST of the right UF sub-tract and severity of social anxiety symptoms (LSAS, r_s=-0.480, p=0.024; SIAS, r_s=-0.580, p=0.005; SPS, r_s=-0.590, p=0.004; FNE, r_s=-0.675, p=0.001) in patients with SAD. Conclusion : Although patients with SAD did not show quantitative abnormalities in the UF sub-tact connecting face-specific brain regions, this structure seems to play a role in the symptom severity of SAD.

• Journal of Labour Economics
• /
• v.29 no.2
• /
• pp.1-27
• /
• 2006

Recent migration is led by skilled labor, This paper performes a cross-country analysis to find the determinants of skilled migration using recently released Doquier and Marfouk(2005) data as dependent variable and economic indicators of nations as independent variables. Regression results show that the skilled migration to OECD countries are driven not only by income motive but also by structural factors, such as industrial structure and life expectancy, which have broader meanings in development. It is noteworthy that structural factors of a nation become more important as its income level rises. English seems to have positive effect on skilled migration. Some region-specific factors, proximity to USA of Caribbean countries and political instability of Gold Coast countreis, for example, are found. Middle-income countries seem to be the most vulnerable to the possible risk of brain drain.

• Korean Journal of Veterinary Research
• /
• v.39 no.1
• /
• pp.45-54
• /
• 1999

In the present study we have analyzed the characteristics and distribution of the mu-opioid receptor(MOR) by raising anti-peptide antisera to the C-terminal peptide of MOR. The antisera against MOR was produced in New Zealand White rabbit against 15 residue corresponding to amino acids, 384-398 of the cloned rat MOR. The antigenic peptide was synthesized using an Applied Biosystems 432 solid-phase peptide synthesizer. The specificity and identification of the antisera were tested by analysis of transfected cells, epitope mapping and immunohistochemical method. COS-7 cells electroporated with MOR cDNA were used to evaluate the characteristics and subcellular distribution of MOR. MOR immunoreactivity was prodominent in the plasmalemma and subcellular compartments such as endoplasmic reticulum, Golgi apparatus and vesicle like structure. Furthermore, both tissue sections and transfected cell lines could be immunostained with these antisera and the immunoreactivity was abolished when anti-MOR sera were preincubated with the peptide against which they were raised. Based on epitope mapping analysis, all antisera appeared to have a similar epitope, which was determined to be within the last amino acid, 391-398. Moreover, immunohistochemistry showed that MOR immunoreactivity was observed in many brain areas including cerebral cortex, striatum, hippocampus, locus coeruleus and the superficial laminae of the dorsal horn. These stained spinal cord and brain areas showed the mirrored pattern observed in auto radiographic studies of mu-opioid binding as well as a pattern similar to that seen by is situ hybridization for MOR. Thus, several lines of evidence support the conclusion that the antisera produced in the present study most likely recognize mu-opioid receptor. These results suggest that MOR antisera may be utilized as useful tool to analyze the physiological and pharmacological studies for mu-opioid receptor in the future.

• The Korean Journal of Nuclear Medicine
• /
• v.24 no.2
• /
• pp.215-221
• /
• 1990

HM-PAO was synthesized by two step reaction. d, 1-HM-PAO was separated from the racemic product by fractional recrystalization in ethylacetate, and the chemical structure and purity was confirmed by proton NMR spectroscopy. The synthesized 0, 1-HM-PAO was labeled with $^{99m}Tc$ and studied the biodistribution in mice. From the results we could find that liver uptake of synthesized $^{99m}Tc$ d, 1-HM-PAO was higher than that of Amersham kit, but no conspicuous difference was found in brain and other tissues (blood, lung, stomach, intestine, muscle, spleen and kidney).

• Applied Microscopy
• /
• v.48 no.3
• /
• pp.55-61
• /
• 2018

The synaptic vesicle is a specialized structure in presynaptic terminals that stores various neurotransmitters. The actin filament has been proposed for playing an important role in mobilizing synaptic vesicles. To understand the role of actin filament on synaptic vesicle pooling, we characterized synaptic vesicles and actin filament after treatment of brain-derived neurotrophic factor (BDNF) or Latrunculin A on primary cultured neuron from rat embryo hippocampus. Western blots revealed that BDNF treatment increased the expression of synapsin I protein, but Latrunculin A treatment decreased the synapsin I protein expression. The increased expression of synapsin I after BDNF disappeared by the treatment of Latrunculin A. Three-dimensional (3D) tomography of synapse showed that more synaptic vesicles localized near the active zone and total number of synaptic vesicles increased after treatment of BDNF. But the number of synaptic vesicle was 2.5-fold reduced in presynaptic terminals and the loss of filamentous network was observed after Latrunculin A application. The treatment of Latruculin A after preincubation of BDNF group showed that synaptic vesicle number was similar to that of control group, but filamentous structures were not restored. These data suggest that the actin filament plays a significant role in synaptic vesicles pooling in presynaptic terminals.