• The Korean journal of internal medicine
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• v.34 no.1
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• pp.146-155
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• 2019

Background/Aims: Indoxyl sulfate (IS) is a uremic toxin and an important causative factor in the progression of chronic kidney disease. Recently, paricalcitol (19-nor-1,25-dihydroxyvitamin D2) was shown to exhibit protective effects in kidney injury. Here, we investigated the effects of paricalcitol treatment on IS-induced renal tubular injury. Methods: The fluorescent dye 2',7'-dichlorofluorescein diacetate was used to measure intracellular reactive oxygen species (ROS) following IS administration in human renal proximal tubular epithelial (HK-2) cells. The effects of IS on cell viability were determined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays and levels of apoptosis-related proteins (Bcl-2-associated protein X [Bax] and B-cell lymphoma 2 [Bcl-2]), nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) p65, and phosphorylation of mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) were determined by semiquantitative immunoblotting. The promoter activity of $NF-{\kappa}B$ was measured by luciferase assays and apoptosis was determined by f low cytometry of cells stained with f luorescein isothiocyanate-conjugated Annexin V protein. Results: IS treatment increased ROS production, decreased cell viability and induced apoptosis in HK-2 cells. IS treatment increased the expression of apoptosis-related protein Bax, decreased Bcl-2 expression, and activated phosphorylation of MAPK, $NF-{\kappa}B$ p65, and Akt. In contrast, paricalcitol treatment decreased Bax expression, increased Bcl-2 expression, and inhibited phosphorylation of MAPK, $NF-{\kappa}B$ p65, and Akt in HK-2 cells. $NF-{\kappa}B$ promoter activity was increased following IS, administration and was counteracted by pretreatment with paricalcitol. Additionally, flow cytometry analysis revealed that IS-induced apoptosis was attenuated by paricalcitol treatment, which resulted in decreased numbers of fluorescein isothiocyanate-conjugated Annexin V positive cells. Conclusions: Treatment with paricalcitol inhibited IS-induced apoptosis by regulating MAPK, $NF-{\kappa}B$, and Akt signaling pathway in HK-2 cells.

• Annals of Clinical Neurophysiology
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• v.6 no.1
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• pp.20-25
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• 2004

Background and Objectives: The proximal and distal nerve segments are preferentially involved in acquired demyelinating polyneuropathies (ADP). This study was undertaken in order to assess the usefulness of motor evoked potential (MEP) and somatosensory evoked potential (SSEP) in the detection of the proximal nerve lesion in ADP. Methods: MEP, SSEP and conventional NCS were performed in 6 consecutive patients with ADP (3 AIDP, 3 CIDP). MEP was recorded from abductor pollicis brevis and abductor hallucis using magnetic stimulation of the cortex and the cervical/lumbar spinal roots. SSEP were elicited by stimulating the median and posterior tibial nerves. Latency from cortex and cervical/lumbar roots, central motor conduction time (CMCT), EN1-CN2 interpeak latency were measured for comparison. Results: MEP was recorded in 24 limbs (12 upper and 12 lower limbs) and SSEP in 24 limbs (12 median nerve, 12 posterior tibial nerve). F-wave latency was prolonged in 25 motor nerves (25/34, 73.5%). Prolonged CML and PML were found in 41.7% (10/24) and 45.8% (11/24), respectively. Interside difference (ISD) of CMCT was abnormally increased in the upper extremity, 66.7% (4/6 pairs) in case of CML-PML. EN1-CN2 interpeak latency was abnormally prolonged in one median nerve (1/10) and LN1-P1 interpeak latency was normal in all posterior tibial nerves. Conclusions: MEP and SSEP may provide useful information for the proximal nerve and root lesion in ADP. MEP and SSEP is supplemental examination as well as complementary to conventional NCS.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.2
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• pp.415-433
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• 1998

Digora system is an intraoral indirect digital radiography system utilizing storage phosphor image plate. It has wide dynamic range which allows it to decrease the patient s exposure time and may increase diagnostic ability through image processing (such as edge enhancement, grey scale conversion, brightness change, and contrast enhancement). And also, it can transmit and storage image information. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries between Conventional radiograph and Digora images(unenhanced image, brightness & contrast controlled image, and edge enhanced image). ROC(Receiver Operating Characteristic) analysis, paired t-tests, and F-tests were done for the statistical evaluation of detectability. The following results were acquired: 1. In Grade I lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.953, 0.933, 0.965, 0.978 (p>0.05). 2. In Grade II lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.969, 0.964, 0.988, 0.994. Among theses areas, there was just statistical significance between Diagnostic abilities of Digora edge enhanced image and Conventional radiograph (p<0.05). 3. In the Interobserver variability, the ROC curve areas of Digora edge enhanced image was lowermost in these areas, regardless of the Carious lesion depths. In conclusion, intraoral indirect digital system, Digora system, has the potential possibility as an alternative of Conventional radiograph in the diagnosis of proximal caries.

• The Journal of Korea Robotics Society
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• v.16 no.2
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• pp.147-154
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• 2021

One of the most challenging issues when robots interact with the environment is to establish contact quickly and avoid high impact force at the same time. The proposed method implements the passive suspension system using the redundancy of the torque-controlled robot. Instead of utilizing the actual mechanical compliance, the distal joints near the end-effector are controlled to act as a virtual spring-damper system with low feedback gains. The proximal joints are precisely controlled to push the mid-link, which is defined as the boundary link between the proximal and distal joints, towards the environment with high feedback gains. Compared to the active compliance methods, the contact force measurements or estimates are not required for contact establishment and the control time delay problems do not occur correspondingly. The proposed method was applied to the landing foot control of the 12-DoF biped robot DYROS-RED in the simulations. In the results, the impact force during landing was significantly reduced at the same collision speed.

• Journal of the Korean Applied Science and Technology
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• v.24 no.1
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• pp.61-66
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• 2007

X-ray diffraction studies have been made to investigate the effects of binding of ADP, ADP+Vi, ADP+AIF4, $ADP+BeF_3$ on the structure of glycerinated rabbit skeletal muscle in the rigor state. Although these phosphate analogs are known to bind actively cycling myosin heads, it is not clear whether they can bind to the attached heads in the rigor muscle. We have found that these analogs can bind to the myosin heads attached to actin filaments in the rigor state. The present results indicate that (1) bound myosin heads altered their conformation in the proximal end toward the plane perpendicular to the fiber axis when MgADP bound to them, and (2) myosin heads were dissociated substantially (up to 50%) from actin filaments but still remained in the vicinity of actin filaments when MgADP and metallofluorides (AIF4 and BeF3) or vanadate bound to them. We detected new conformations of myosin heads attached to actin filaments when they had MgADP or ADP.Pi analogs. We report here these findings on the effects of MgADP and MgADP+phosphate analogs to the rigor crossbridges.

• Journal of dental hygiene science
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• v.12 no.1
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• pp.39-44
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• 2012

For the purpose of examining the dental biofilm reduction effect and control difficulty level through a dental biofilm control program in this study, the total of 131 medical records (82.9%) were used for the final analysis upon excluding the records that were not suitable for this study among the records of 158 persons for the medical records of clinical hygiene case reports that were submitted from 2006 to 2011 by students at the Department of Dental Hygiene at N University located in Chungnam region. The result of examining the dental biofilm reduction effect according to the visit number when conducting a dental biofilm control program showed that the dental biofilm index reduced meaningfully as the visit number increased. However, in the case of those that visited for 7 sessions, the level of reduction was not statistically meaningful. For the purpose of comparing the dental biofilm index mean per area of teeth during the final session visit of dental biofilm control program, the area of teeth was classified into labial/buccal surface, lingual/palatal surface and proximal surface, and the dental biofilm index of lingual/palatal surface was the highest with 26.5%. The result of measuring the dental biofilm of maxilla/mandible revealed meaningful differences between the dental biofilm index of maxilla and mandible. The result of analyzing the dental biofilm index of labial/buccal surface, lingual/palatal surface and proximal surface revealed meaingful differences among the dental biofilm index of labial/ buccal surface, lingual/palatal surface and proximal surface.

• Korean Journal of Animal Reproduction
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• v.27 no.3
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• pp.225-231
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• 2003

Transgenic mice containing Diphtheria Toxin-A (DT-A) gene fused to proximal lck promoter sequences was used for analysis of DT-A gene expression and thymocyte development. The diphtheria toxin gene was expressed in thymus, spleen and liver of transgenic mice confirmed by RT-PCR and Northern blotting. A FACS analysis with thymocyte cell surface antigens antibodies (CD4 and CD8) showed that the number of peripheral mature single positive thymocytes ($CD4^{+}\;and\;CD8^{+}$ cells) T-cells was severely reduced in transgenic mice compared to that in the non-transgenic littermates. A relative portion of $CD8^{+}$ single positive thymocytes was about 33.2% in transgenic peripheral T-cells while 50.6% in wild type. Reduction of $CD4^{+}$ cell numbers in transgenic mice was observed (5.9% in transgenic versus 10.3% in non-transgenic). The data from analysis of these transgenic mice indicate that the proximal lck promoter regulated the expression of DT-A gene at high level in developing thymocytes and the DT-A disrupted developing thymocytes in transgenic mice.

• Journal of Chest Surgery
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• v.25 no.1
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• pp.1-16
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• 1992

The quantitatively measured local myocardial perfusion rates with microspheres are used as an objective indicator of even distribution of cardioplegic solution, and the efficacy of the retrograde right atrial route of cardioplegia is evaluated in hearts with various levels of coronary arterial obstruction. After initial antegrade cardioplegia under the median sternotomy and aortic cannulation, 60 hearts from anesthetized New Zealand white rabbits are divided in random order as normal group [ligated left main coronary artery ; MA, MR] and diagonal group [ligated proximal diagonal artery ; LA, LR]. Half of each group [N=10] are perfused with antegrade cardioplegia[A] under the pressure of 100 cmH2O and the other half with retrograde right atrial route[R] under the pressure of 60 cmH2O[St. Thomas cardioplegic solution mixed with measured amount of microspheres]. The myocardium is subdivided into segments as A[atria], RV[right ventricle]. S[septum], LV[normally perfused left ventricular free wall], ROI[ischemic myocardium of left ventricular free wall]. LV and RQI are further divided into N[subendocardium] and P[subepicardium]. The resulting local myocardial perfusion rates and N /P of each group are compared with Wilcoxon rank sum test. The weight of the hearts is 5.94$\pm$0.66g, and there are no statistically significant dif-ferences[p>0.05, ANOVA] between six compared group. The mean flow rate[F: ml /g / min] of MR group is comparable with MA group[p>0.05], but in N and L group, there are significantly depressed F with right atrial route of cardioplegia, which means elevated perfusion resistance with this route. In spite of no significant differences in delivered doses of microsphere[DEL] between compared groups[p>0.05, ANOVA], there are significantly depressed REC and NF in hearts with right atrial cardioplegia which suggests increased requirement of cardioplegic solution with this route. The interventricular septum shows poor perfusion with right atrial route of cardioplegia without obstruction of supplying coronary arteries. But, with obstruction of coronary artery supplying septum as in M group, the flow rate is superior with right atrial route of infusion. The left ventricular free wall perfusion rates of every RQI with R route are superior to that of A route[p<0.05]. But, in LV segments, there are unfavorable effects of right atrial cardioplegia in L group, although the subendocardial perfusion is well maintained in N group. The LV free wall of left main group shows depressed perfusion rates with antegrade route as compared with RQI segments of diagonal group. But, by contraries, there are increased perfusion rates and superior N /P ratio with retrograde right atrial route. It implies more effective perfusion with right atrial route of cardioplegia in more proximal coronary arterial obstruction[i.e., M group as compared with L group]. As a conclusion, all region of ischemia have superior perfusion rates with right atrial car-dioplegia as compared with antegrade route, and especially excellent results can be obtained in hearts with more proximal obstruction of coronary arteries which would otherwise result in more severe ischemic damage. But, the depressed perfusion rates of the segments with normal coronary artery in hearts with coronary arterial obstruction may be a problem of concern with right atrial cardioplegia and needs solution.

• Parasites, Hosts and Diseases
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• v.52 no.2
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• pp.193-196
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• 2014

Fascioliasis is a zoonotic infection caused by Fasciola hepatica or Fasciola gigantica. We report an 87-year-old Korean male patient with postprandial abdominal pain and discomfort due to F. hepatica infection who was diagnosed and managed by endoscopic retrograde cholangiopancreatography (ERCP) with extraction of 2 worms. At his first visit to the hospital, a gallbladder stone was suspected. CT and magnetic retrograde cholangiopancreatography (MRCP) showed an intraductal mass in the common bile duct (CBD) without proximal duct dilatation. Based on radiological findings, the presumed diagnosis was intraductal cholangiocarcinoma. However, in ERCP which was performed for biliary decompression and tissue diagnosis, movable materials were detected in the CBD. Using a basket, 2 living leaf-like parasites were removed. The worms were morphologically compatible with F. hepatica. To rule out the possibility of the worms to be another morphologically close species, in particular F. gigantica, 1 specimen was processed for genetic analysis of its ITS-1 region. The results showed that the present worms were genetically identical (100%) with F. hepatica but different from F. gigantica.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1241-1245
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• 1999

Nine two-year old sheep fitted with rumen and duodenum cannulas were used to study the effect of controlling protozoa flora on the degradation and utilization of dietary fibre and protein in the rumen and on nitrogenous flow to the duodenum. There were three groups in this experiment: defaunation (DF); partial defaunation (PDF); faunation (F) as control. Results showed that: 1,There were no differences between treatments in dietary DM degradation in the rumen, but defaunation and partial defaunation increased the quantity of nitrogenous material in the rumen and the flow of N to duodenum. 2, partial defaunation and defaunation improved the degradabilities of dietary NDF, ADF and HC, but there were no differences between the defaunated and partially defaunated groups. 3, Partial defaunation decreased the degradability of dietary protein in the rumen. There was no difference between defaunated and faunated groups. 4, Defaunation and partial defaunation increased the quantity of total N (TN) and microbial N (MCN) in the rumen and the amounts entering the duodenum. The protozoa N (PN) flow in the faunated group was higher than that in the partially defaunated group, and the amino acid pattern in the digesta at the proximal duodenum in the defaunated group was closer to the ideal amino acid pattern. 5, There were differences in the mole percent of acetic, propionic, total-VFAs and the non-glucogenic to glucogenic VFAs ratio (NGR) value in the rumen fluids. The order was as follows: mole percent of acetate: F>PDF>DF; mole percent of propionate: DF>PDF>F; total-VFAs: PDF>F>DF; NGR: F>PDF>DF.