• Natural Product Sciences
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• v.19 no.4
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• pp.290-296
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• 2013

In preliminary tests, we examined the effect of several fractions isolated from fermented pine needle extract on pacemaker potentials in cultured interstitial cells of Cajal (ICCs) from the mouse colon using a whole cell patch clamp technique. Among these fractions, Fraction 3 (F3) elicited the most powerful depolarization of membrane. Therefore, the aim of the present study was to investigate the effect of F3 obtained from fermented extract of Pinus densiflora needle on pacemaker potentials in ICCs and to establish its mechanism of action. Colonic ICCs generated spontaneous periodic pacemaker potentials in the current-clamp mode. F3 depolarized the membrane and decreased the frequency and amplitude of pacemaker potentials in a dose-dependent fashion. The F3-induced effects on pacemaker potentials were blocked by methoctramine, a muscarinic $M_2$ receptor antagonist, and by glycopyrrolate, a muscarinic $M_3$ receptor antagonist. The F3-induced effects on pacemaker potentials were blocked by external $Na^+$-free solution and by flufenamic acid, a non-selective cation channel blocker, as well as by the removal of external $Ca^{2+}$ and in the presence of thapsigargin, a $Ca^{2+}$-ATPase inhibitor in the endoplasmic reticulum. Taken together, these results suggest that F3 of pine needle extract modulates the pacemaker activity of colonic ICCs by the activation of non-selective cation channels via muscarinic $M_2$ and $M_3$ receptors. And external $Ca^{2+}$ influx and intracellular $Ca^{2+}$ release are involved in F3 actions on ICCs.

• Journal of Life Science
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• v.29 no.9
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• pp.1010-1015
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• 2019

The interstitial cells of Cajal (ICCs) are the pacemaker cells in the gastrointestinal (GI) tract. In the present study, the effects of olanzapine, an atypical antipsychotic agent, on pacemaker potentials in cultured ICCs from the small intestine of the mouse were investigated. The whole-cell patch-clamp configuration was used to record pacemaker potentials from cultured ICCs. Olanzapine produced pacemaker depolarizations in a concentration-dependent manner in current clamp mode. Methoctramine, a muscarinic $M_2$ receptor antagonist, did not inhibit olanzapine-induced pacemaker depolarizations, whereas 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) muscarinic $M_3$ receptor antagonist did inhibit it. When guanosine 5'-[${\beta}$-thio] diphosphate (GDP-${\beta}$-S; 1 mM) was in the pipette solution, olanzapine-induced pacemaker depolarization was blocked. Also, low $Na^+$ solution externally eliminated the generation of pacemaker potentials and inhibited the olanzapine-induced pacemaker depolarizations. Additionally, the nonselective cation channel blocker, flufenamic acid, inhibited the olanzapine-induced pacemaker depolarizations. Pretreatment with U-73122, an active phospholipase C (PLC) inhibitor, also eliminated the generation of pacemaker potentials and suppressed the olanzapine-induced pacemaker depolarizations. These results suggested that olanzapine modulates the pacemaker potentials through muscarinic $M_3$ receptor activation by G protein-dependent external $Na^+$ and PLC pathway in the ICCs. Therefore, olanzapine could affect intestinal motility through ICCs.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.4
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• pp.193-198
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• 2006

Many gastrointestinal muscles show electrical oscillation, so-called 'slow wave', originated from interstitial cells of Cajal (ICCs). Thus, a technique to freshly isolate the cells is indispensable to explore the electrophysiological properties of the ICCs. To apply an enzyme solution on the serosal surface for cell isolation, the intestine was inverted and 0.02% trypsin solution and 0.04% collagenase solution were applied to serosal cavity. After the enzyme treatment, mucosal layer was removed and longitudinal muscle layer was gently separated from the rest of tissue. The thin layer was stretched in the recording chamber and mounted on an inverted microscope. Using ${\beta}-escine$, perforated whole cell patch clamp technique was used. Under a microscope, the tissue showed smooth muscle cells and interstitial cells around the myenteric plexus. Under voltage clamp condition, three types of membrane potential were recorded. One group of interstitial cells, which were positive to methylene blue and CD34, showed spontaneous outward current. These cells had bipolar shape and were considered as fibroblast-like cells because of their peculiar shape and arrangement. Another group, positive to c-kit and methylene blue, showed spontaneous inward current. These cells had more rounded shape and processes and were considered as ICCs. The third, positive to c-kit and had granules containing methylene blue, showed quiet membrane potentials under the voltage-clamp mode. These cells appeared to be resident macrophages. Therefore, in the freshly isolated thin tissue preparation, methylene blue could easily identify three types of cells rather than morphological properties. Using this method, we were able to study electrical properties of fibroblast and residential macrophage as well as myenteric ICCs.

• Investigative Magnetic Resonance Imaging
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• v.19 no.3
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• pp.168-177
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• 2015

Purpose: Brain surface intensity model (BSIM)-based cortical thickness analysis does not require complicated 3D segmentation of brain gray/white matters. Instead, this technique uses the local intensity profile to compute cortical thickness. The aim of the present study was to evaluate intra-rater and inter-rater reliability of BSIM-based cortical thickness analysis using images from elderly participants. Materials and Methods: Fifteen healthy elderly participants (ages, 55-84 years) were included in this study. High-resolution 3D T1-spoiled gradient recalled-echo (SPGR) images were obtained using 3T MRI. BSIM-based processing steps included an inhomogeneity correction, intensity normalization, skull stripping, atlas registration, extraction of intensity profiles, and calculation of cortical thickness. Processing steps were automatic, with the exception of semiautomatic skull stripping. Individual cortical thicknesses were compared to a database indicating mean cortical thickness of healthy adults, in order to produce Z-score thinning maps. Intra-class correlation coefficients (ICCs) were calculated in order to evaluate inter-rater and intra-rater reliabilities. Results: ICCs for intra-rater reliability were excellent, ranging from 0.751-0.940 in brain regions except the right occipital, left anterior cingulate, and left and right cerebellum (ICCs = 0.65-0.741). Although ICCs for inter-rater reliability were fair to excellent in most regions, poor inter-rater correlations were observed for the cingulate and occipital regions. Processing time, including manual skull stripping, was $17.07{\pm}3.43min$. Z-score maps for all participants indicated that cortical thicknesses were not significantly different from those in the comparison databases of healthy adults. Conclusion: BSIM-based cortical thickness measurements provide acceptable intra-rater and inter-rater reliability. We therefore suggest BSIM-based cortical thickness analysis as an adjunct clinical tool to detect cortical atrophy.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.4
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• pp.341-346
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• 2014

Lubiprostone is a chloride ($Cl^-$) channel activator derived from prostaglandin $E_1$ and used for managing constipation. In addition, lubiprostone affects the activity of gastrointestinal smooth muscles. Interstitial cells of Cajal (ICCs) are pacemaker cells that generate slow-wave activity in smooth muscles. We studied the effects of lubiprostone on the pacemaker potentials of colonic ICCs. We used the whole-cell patch-clamp technique to determine the pacemaker activity in cultured colonic ICCs obtained from mice. Lubiprostone hyperpolarized the membrane and inhibited the generation of pacemaker potentials. Prostanoid $EP_1$, $EP_2$, $EP_3$, and $EP_4$ antagonists (SC-19220, PF-04418948, 6-methoxypyridine-2-boronc acid N-phenyldiethanolamine ester, and GW627368, respectively) did not block the response to lubiprostone. L-NG-nitroarginine methyl ester (L-NAME, an inhibitor of nitric oxide synthase) and 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ, an inhibitor of guanylate cyclase) did not block the response to lubiprostone. In addition, tetraethylammonium (TEA, a voltage-dependent potassium [$K^+$] channel blocker) and apamin (a calcium [$Ca^{2+}$]-dependent $K^+$ channel blocker) did not block the response to lubiprostone. However, glibenclamide (an ATP-sensitive $K^+$ channel blocker) blocked the response to lubiprostone. Similar to lubiprostone, pinacidil (an opener of ATP-sensitive $K^+$ channel) hyperpolarized the membrane and inhibited the generation of pacemaker potentials, and these effects were inhibited by glibenclamide. These results suggest that lubiprostone can modulate the pacemaker potentials of colonic ICCs via activation of ATP-sensitive $K^+$ channel through a prostanoid EP receptor-independent mechanism.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1797-1808
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• 2021

Objective: To determine whether volumetric CT texture analysis (CTTA) using fully automatic tumor segmentation can help predict recurrence-free survival (RFS) in patients with intrahepatic mass-forming cholangiocarcinomas (IMCCs) after surgical resection. Materials and Methods: This retrospective study analyzed the preoperative CT scans of 89 patients with IMCCs (64 male; 25 female; mean age, 62.1 years; range, 38-78 years) who underwent surgical resection between January 2005 and December 2016. Volumetric CTTA of IMCCs was performed in late arterial phase images using both fully automatic and semi-automatic liver tumor segmentation techniques. The time spent on segmentation and texture analysis was compared, and the first-order and second-order texture parameters and shape features were extracted. The reliability of CTTA parameters between the techniques was evaluated using intraclass correlation coefficients (ICCs). Intra- and interobserver reproducibility of volumetric CTTAs were also obtained using ICCs. Cox proportional hazard regression were used to predict RFS using CTTA parameters and clinicopathological parameters. Results: The time spent on fully automatic tumor segmentation and CTTA was significantly shorter than that for semi-automatic segmentation: mean ± standard deviation of 1 minutes 37 seconds ± 50 seconds vs. 10 minutes 48 seconds ± 13 minutes 44 seconds (p < 0.001). ICCs of the texture features between the two techniques ranged from 0.215 to 0.980. ICCs for the intraobserver and interobserver reproducibility using fully automatic segmentation were 0.601-0.997 and 0.177-0.984, respectively. Multivariable analysis identified lower first-order mean (hazard ratio [HR], 0.982; p = 0.010), larger pathologic tumor size (HR, 1.171; p < 0.001), and positive lymph node involvement (HR, 2.193; p = 0.014) as significant parameters for shorter RFS using fully automatic segmentation. Conclusion: Volumetric CTTA parameters obtained using fully automatic segmentation could be utilized as prognostic markers in patients with IMCC, with comparable reproducibility in significantly less time compared with semi-automatic segmentation.

• Journal of Korean Physical Therapy Science
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• v.8 no.1
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• pp.917-921
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• 2001

The purpose of this study was to examine the difference in measurements of passive range of motion(PROM) of shoulder when motions are assessed in sitting, as compared with supine and the intratester and intertester reliabilities for goniometric measurements of shoulder PROM using two different sizes of goniometers. * A thesis submitted to the committee of Graduate School of Public Health, Chungnam National University in partial fulfillment of the requirements for the degree of Master of Public Health conferred in February 2001. Fifty one adult male subjects were measured three times, in random order, for the six shoulder motions(flexion, extension, abduction, adduction, external rotation, and internal rotation) while sitting and supine by three different therapists. Data were analyzed to determine intraclass correlation coefficients (ICCs) and paired "t" values between trials for measurements with different goniometer and betweensitting and supine trials. There was statistical difference in measurement of shoulder motion between supine and sitting position and no statistical difference in goniometric type. The intratester intraclass correlation coefficients (ICCs) for all motions ranged from .87 to .98. The ICCs for the intertester reliability of PROM measurements of all shoulder motion ranged from .26 to .89. These findings suggest that reliable measures of PROM of the shoulder can be obtained using standard goniometry in a proper position.

• The Journal of Korean Physical Therapy
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• v.25 no.4
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• pp.174-179
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• 2013

Purpose: Visual gait analysis plays a pivotal role in determining the important gait problem of patients. A few studies have been published and have received little attention regarding visual gait analysis on patients with orthopedic problems. The purposes of this study were to investigate the difference of reliability levels according to experience of clinical physical therapists. Methods: Thirty-five clinical physical therapists, 5 high experienced, 15 experienced, and 15 inexperienced, were recruited and individually evaluated these videotaped gait patterns of the participants, and filled up the structured gait analysis form. The gait of nine participants was videotaped. Reliability levels were calculated by the Intraclass Correlation Coefficients (ICC). Results: The inter-rater reliability of high experienced group (ICC=0.56; 95% CI: 0.50-0.62) was comparable to that of the experienced raters (ICC=0.48; 95% CI: 0.43-0.53) and inexperienced group (ICC=0.42; 95% CI: 0.38-0.46). High experienced group reached a higher inter-rater reliability level. The average intra-rater reliability of the high experienced group was 0.70 (ICCs ranging from 0.54 to 0.82). The experienced group reached an average intra-rater reliability of 0.61 (ICCs ranging from 0.47 to 0.81). The inexperienced group attained average ICC values of 0.53 (ICCs ranging from 0.30 to 0.74). Conclusion: Use of a structured gait analysis form as described in this study was found to be moderately reliable. Clinical experience appears to increase the reliability of visual gait analysis.

• Journal of Life Science
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• v.31 no.7
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• pp.662-670
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• 2021

Interstitial cells of Cajal (ICCs) are the pacemaking cells in the gastrointestinal (GI) muscles that generate the rhythmic oscillation in membrane potentials known as slow waves. In the present study, we investigated the effects of mirtazapine, a noradrenergic and serotonergic antidepressant, on pacemaking potential in cultured ICCs from the murine small intestine. The whole-cell patch-clamp configuration was used to record pacemaker potential in cultured ICCs. Mirtazapine induced pacemaker potential depolarizations in a concentration-dependent manner in the current clamp mode. Y25130 (a 5-HT3 receptor antagonist), RS39604 (a 5-HT4 receptor antagonist), and SB269970 (a 5-HT7 receptor antagonist) had no effects on mirtazapine-induced pacemaker potential depolarizations. Also, methoctramine, a muscarinic M₂ receptor antagonist, had no effect on mirtazapine-induced pacemaker potential depolarizations, whereas 4-diphenylacetoxy-N-methyl-piperidine methiodide (4-DAMP), a muscarinic M₃ receptor antagonist, inhibited the depolarizations. When guanosine 5'-[β-thio] diphosphate (GDP-β-S; 1 mM) was in the pipette solution, mirtazapine-induced pacemaker potential depolarization was blocked. When an external Ca²⁺ free solution or thapsigargin, a Ca²⁺-ATPase inhibitor of the endoplasmic reticulum, was applied, the generation of pacemaker potentials disappeared, and under these conditions, mirtazapine induced pacemaker potential depolarizations. In addition, protein kinase C (PKC) inhibitor, calphostin C, and chelerythrine inhibited mirtazapine-induced pacemaker potential depolarizations. These results suggest that mirtazapine regulates pacemaker potentials through muscarinic M₃ receptor activation via a G protein-dependent and an external or internal Ca²⁺-independent PKC pathway in the ICCs. Therefore, mirtazapine can control GI motility through ICCs.

• The Journal of Korean Physical Therapy
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• v.14 no.1
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• pp.177-186
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• 2002

The purpose of this study was to contribute to the development of clinical instruction by students ratings of teaching effectiveness in clinical education. The instrument used in this study was teaching effectiveness of clinical nursing by Yu and modified evaluation method by Kern and Mickelson. The results were are follows 1. Among the 12 categorial components of clinical teaching effectiveness, the highest satisfaction was 'encouraging to think for themselves' and the lowest was 'attitude of teacher and evaluation' 2. To compare teaching effectiveness between sex, 'resource for student' and 'professional competence' showed statistical significance. 3. To compare teaching effectiveness among clinical practice stage, 'encouraging' 'role model', 'professional competence', 'organization of subject mater' and 'attitude of teacher and evaluation' showed statistical significance. 5. Interrater ICCs for evaluation method did not showed statistical significance and interitem ICCs showed statistical significance. This article presents goal of clinical education, development of clinical instructor's educational program and a standardized method to measure clinical performance.