• Biomolecules & Therapeutics
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• v.28 no.4
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• pp.328-336
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• 2020

Diabetes mellitus affects the colonic motility developing gastrointestinal symptoms, such as constipation. The aim of the study was to examine the role of intracellular signaling pathways contributing to colonic dysmotility in diabetes mellitus. To generate diabetes mellitus, the rats were injected by a single high dose of streptozotocin (65 mg/kg) intraperitoneally. The proximal colons from both normal and diabetic rats were contracted by applying an electrical field stimulation with pulse voltage of 40 V in amplitude and pulse duration of 1 ms at frequencies of 1, 2, 4, and 6 Hz. The muscle strips from both normal rats and rats with diabetes mellitus were pretreated with different antagonists and inhibitors. Rats with diabetes mellitus had lower motility than the control group. There were significant differences in the percentage of inhibition of contraction between normal rats and rats with diabetes mellitus after the incubation of tetrodotoxin (neuronal blocker), atropine (muscarinic receptor antagonist), prazosin (α₁ adrenergic receptor antagonist), DPCPX (adenosine A1 receptor antagonist), verapamil (L-type Ca²⁺ channel blocker), U73122 (PLC inhibitor), ML-9 (MLCK inhibitor), udenafil (PDE₅ inhibitor), and methylene blue (guanylate cyclase inhibitor). The protein expression of p-MLC and PDE₅ were decreased in the diabetic group compared to the normal group. These results showed that the reduced colonic contractility resulted from the impaired neuronal conduction and decreased muscarinic receptor sensitivity, which resulted in decreased phosphorylation of MLC via MLCK, and cGMP activity through PDE₅.

• Korean Journal of Acupuncture
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• v.28 no.1
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• pp.1-13
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• 2011

Objectives : The object of this study is to evaluate and develop the system that reflects acupoints electrical properties by the multi-frequency using the SPAC (Single Power Alternative Current) stimulation method based on BIA (Bioelectrical impedance method). Methods : The 12 channel meridian impedance measurement system (MIMS) was designed, which sets multi-frequency with 10 steps (1~10kHz). To check acupoints electrical properties, impedance of acupoints were measured from 11 acupoints selected from the LU and ST meridians. Results : Regarding distribution of measurement values by multi-frequencies, we found the lowest response at 1kHz was in common. But frequency bands which represent the highest response at each acupoint were various. Measurement values of each acupoint by multi-frequencies were expressed similar distribution (P<0.05). Also we could check same frequency band which showed the highest response at left/right equal acupoints (P<0.05). Conclusions : Through change of acupoints electrical properties by multi-frequency stimulation, we checked oriental medical diagnostic possibilities by using this system. We would progress variable clinical trials with this system for oriental medical diagnosis.

• Atmosphere
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• v.27 no.2
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• pp.119-131
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• 2017

We present and discuss the Tropopause Folding Turbulence Detection (TFTD) algorithm for the Korean Communication, Ocean, Meteorological Satellite (COMS) which is originally developed for the Tropopause Folding Turbulence Product (TFTP) from the Geostationary Operational Environmental Satellite (GOES)-R. The TFTD algorithm assumes that the tropopause folding is linked to the Clear Air Turbulence (CAT), and thereby the tropopause folding areas are detected from the rapid spatial gradients of the upper tropospheric specific humidity. The Layer Averaged Specific Humidity (LASH) is used to represent the upper tropospheric specific humidity calculated using COMS $6.7{\mu}m$ water vapor channel and ERA-interim reanalysis temperature at 300, 400, and 500 hPa. The comparison of LASH with the numerical model specific humidity shows a strong negative correlation of 80% or more. We apply the single threshold, which is determined from sensitivity analysis, for cloud-clearing to overcome strong gradient of LASH at the edge of clouds. The tropopause break lines are detected from the location of strong LASH-gradient using the Canny edge detection based on the image processing technique. The tropopause folding area is defined by expanding the break lines by 2-degree positive gradient direction. The validations of COMS TFTD is performed with Pilot Reports (PIREPs) filtered out Convective Induced Turbulence (CIT) from Dec 2013 to Nov 2014 over the South Korea. The score test shows 0.49 PODy (Probability of Detection 'Yes') and 0.64 PODn (Probability of Detection 'No'). Low POD results from various kinds of CAT reported from PIREPs and the characteristics of high sensitivity in edge detection algorithm.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.351-356
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• 1999

The present study was aimed at investigating whether the calcium current in the vascular smooth muscle (VSM) cells is altered in renal hypertension. Two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertension were made in Sprague-Dawley rats. Rats without clipping the renal artery or implanting DOCA were used as control for 2K1C and DOCA-salt hypertension, respectively. Four weeks after clipping, systolic blood pressure was significantly higher in 2K1C rats than in control $(192{\pm}24\;and\;119{\pm}4$ mmHg, respectively, n=16 each). DOCA-salt rats also showed a higher blood pressure $(180{\pm}15$ mmHg, n=18) compared with control $(121{\pm}6$ mmHg, n=14). VSM cells were enzymatically and mechanically isolated from basilar arteries. Single relaxed VSM cells measured $5{\sim}10\;{\mu}m$ in width and $70{\sim}150\;{\mu}m$ in length were obtained. VSM cells could not be differentiated in size and shape between hypertensive and normotensive rats under light microscopy. High-threshold (L-type) calcium currents were recorded using whole-cell patch clamp technique. The amplitude of the current recorded from VSM cells was larger in 2K1C hypertension than in control. Neither the voltage-dependence of the calcium current nor the cell capacitance was significantly affected by 2K1C hypertension. By contrast, the amplitude of the calcium current was not altered in DOCA-salt hypertension. These results suggest that high-threshold calcium current of the VSM cells is altered in 2K1C hypertension, and that calcium channel may not be involved in calcium recruitment of VSM in DOCA-salt hypertension.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.5
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• pp.589-602
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• 1998

While ATM technology results in considerable advantages(less overhead, increased throughput) in an optical networks, It causes severe problems(single and burst error) when ATM is transmitted over an error-prone channel, such as wireless link. In this paper we describe our investigation on ATM over wireless network. we first evaluate performance of ATM data transmission over a wireless link. Secondly we analyze performance improvements of Forward Error Correction(FEC) or ARQ(Automatic Repeat reQuest) scheme applied to wireless ATM link and provide performance comparison between FEC and ARQ through the use of packet error rate and throughput. Lastly we suggest error control architecture to overcome the impact of the bit error characteristics of a wireless link on wireless ATM network.

• International Journal of Oral Biology
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• v.31 no.2
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• pp.45-51
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• 2006

R-type($Ca_v2.3$) calcium channel contributes to pain sensation in peripheral sensory neurons. Six isoforms of $Ca_v2.3$ that result from combinations of presence or deletion of three inserts(insert I and insert in the II-III loop, and insert III in N-terminal regions) have been demonstrated to be present in different mammalian tissues. However, the molecular basis of $Ca_v2.3$ in trigeminal ganglion(TG) neurons is not known. In the present study, we determined which isoforms of $Ca_v2.3$ are expressed in rat TG neurons using the RT-PCR analysis. Whole tissue RT-PCR analyses revealed that only two isoforms, $Ca_v2.3a$ and $Ca_v2.3e$, were present in TG neurons. From single-cell RT-PCR, we found that $Ca_v2.3e$ rather than $Ca_v2.3a$ was the major isoform expressed in TG neurons, and $Ca_v2.3e$ was preferentially detected in small-sized neurons that express nociceptive marker, transient receptor potential vanilloid 1(TRPV1). Our results suggest that $Ca_v2.3e$ in trigeminal neurons may be a potential target for the pain treatment.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.4
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• pp.102-107
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• 2011

In this paper, a microfluidic array biochip for simultaneously detecting multiple antigen-antibody bindings was designed and implemented. The biochip has the single channel in which microreaction chambers are serially connected, and the antibody-coated microbeads are packed in each microreaction chamber. In addition, the weir structure was fabricated in the microchannel using the gray-scale photolithography in order to trap the microbeads in the microreaction chamber. Three kinds of antibodies were chosen, and the antibodies were immobilized onto the microbeads by the streptavidin-biotin conjugation. In the experiment, as the fluorescence-labeled antigens were injected into the microchannel, the antigen-antibody bindings were completed in 10 minutes. When the solution with multiple antigens was injected into the microchannel, it was observed that the fluorescence intensity increased in only the corresponding microreaction chambers with few non-specific binding. The microfluidic array biochip implemented in this study provides, even with the consumption of tiny amount of sample and fast reaction time to simultaneously detect multiple immunoreactions.

• Annals of Clinical Neurophysiology
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• v.8 no.2
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• pp.163-170
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• 2006

Backgrounds: MEG can measure the task-specific neurophysiologic activity with good spatial and time resolution. Language lateralization using noninvasive method has been a subject of interest in resective brain surgery. We purposed to develop a paradigm for language lateralization using MEG and validate its feasibility. Methods: Magnetic fields were obtained in 12 neurosurgical candidates and one volunteer for language tasks, with a 306 channel whole head MEG. Language tasks were word listening, reading and picture naming. We tested two word listening paradigms: semantic decision of meaning of abstract nouns, and recognition of repeated words. The subjects were instructed to silently name or read, and respond with pushing button or not. We decided language dominance according to the number of acceptable equivalent current dipoles (ECD) modeled by sequential single dipole, and the mean magnetic field strength by root mean square value, in each hemisphere. We collected clinical data including Wada test. Results: Magnetic fields evoked by word listening were generally distributed in bilateral temporoparietal areas with variable hemispheric dominance. Language tasks using visual stimuli frequently evoked magnetic field in posterior midline area, which made laterality decision difficult. Response during task resulted in more artifacts and different results depending on responding hand. Laterality decision with mean magnetic field strength was more concordant with Wada than the method with ECD number of each hemisphere. Conclusions: Word listening task without hand response is the most feasible paradigm for language lateralization using MEG. Mean magnetic field strength in each hemisphere is a proper index for hemispheric dominance.

• Journal of Marine Bioscience and Biotechnology
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• v.5 no.4
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• pp.40-45
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• 2011

Microalgae are one of the major, sustaining components of ecosystem processes and are responsible for biogeochemical reactions that drive our climate changes. Despite this, many marine microalgae are poorly described and little is known of their abundance and distribution along the coastal areas of Sooyoung Bay, Busan, South Korea. The present study has been conducted from November, 2011 to August, 2009 with the objective to provide an overview of the taxonomy diversity and abundance of microalgae along the coastal areas of the Sooyoung Bay. Water samples were collected from different sites, which were located by using a GPS tracker. Chlorophyll fluorescence of the water samples were measured by using ToxY-PAM dual-channel yield analyzer. The chlorophyll fluorescence values were relatively higher during the spring and summer and even in the region near to the sea port. Similarly the abundance of microalgae was higher near the port but diversity index had lower values. The temperature and pH values were same at all the sites. However, only the temperature varied during the sampling period, with higher values during summer and lower in winter. From the preliminary results, the following class of microalgae were found; Bacillariophyceae, Dinophyceae, Silicoflagellate and Cryptophyceae. With a future ongoing work, microalgae are being isolated to establish single cell culture and for identification using light microscopic observations, photography and molecular approaches.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.217-224
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• 2017

Purpose: Although it is well known thatmortality and morbidity due to cardiovascular diseases are higher in salt-sensitive subjects than in salt-resistant subjects, their underlying mechanisms related to obesity remain unclear. Here, we focused on salt-sensitive gene variants unrelated to monogenic obesity that interacted with sodium intake in humans. Methods: This review was written based on the modified $3^rd$ step of Khans' systematic review. Instead of the literature, subject genes were based on candidate genes screened from our preliminary Genome-Wide Association Study (GWAS). Finally, literature related to five genes strongly associated with salt sensitivity were analyzed to elucidate the mechanism of obesity. Results: Salt sensitivity is a measure of how blood pressure responds to salt intake, and people are either salt-sensitive or salt-resistant. Otherwise, dietary sodium restriction may not be beneficial for everyone since salt sensitivity may be associated with inherited susceptibility. According to our previous GWAS studies, 10 candidate genes and 11 single nucleotide polymorphisms (SNPs) associated with salt sensitivity were suggested, including angiotensin converting enzyme (ACE), ${\alpha}$-adducin1 (ADD1), angiotensinogen (AGT), cytochrome P450 family 11-subfamily ${\beta}$-2 ($CYP11{\beta}$-2), epithelial sodium channel (ENaC), G-protein b3 subunit (GNB3), G protein-coupled receptor kinases type 4 (GRK4 A142V, GRK4 A486V), $11{\beta}$-hydroxysteroid dehydrogenase type-2 (HSD $11{\beta}$-2), neural precursor cell-expressed developmentally down regulated 4 like (NEDD4L),and solute carrier family 12(sodium/chloride transporters)-member 3 (SLC 12A3). We found that polymorphisms of salt-sensitive genes such as ACE, $CYP11{\beta}$-2, GRK4, SLC12A3, and GNB3 may be positively associated with human obesity. Conclusion: Despite gender, ethnic, and age differences in genetics studies, hypertensive obese children and adults who are carriers of specific salt-sensitive genes are recommended to reduce their sodium intake. We believe that our findings can contribute to the prevention of early-onset of chronic diseases in obese children by facilitating personalized diet-management of obesity from childhood to adulthood.