• The Korean Journal of Physiology
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• v.29 no.1
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• pp.13-27
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• 1995

single $K^{+}$ channels of skeletal muscle from the rat and frog were into planar lipid bilayers and their properties were studied. Fusion was induced by an osmotic gradient. Of the four types of $K^{+}$ channels recorded, the two most frequently observed were a voltage and $Ca^{2+}-activated$ $K^{+}$ channel and a $K^{+}$ channel with a prominent conductance substate. The first $K^{+}$ channel was identified as the large $Ca^{2+}-activated$ $K^{+}$ (BK) channel because the open-state probability was increased with depolarization (e-fold change per $10.6{\pm}3.5$ mV, n=8) and internal $Ca^{2+}$ (half-activation at $16.7{\pm}3.8$ mV, n=8, pCa 4) and its conductance was large ($247{\pm}4.9$ pS, n=24 in 0.1 M KCI). Lifetime distributions of open- and closed-states could be fitted with single exponentials of several milliseconds. The mean open- and closed-lifetimes were linearly dependent on the intracellular $[Ca^{2+}]$ and $1/[Ca^{2+}]$, respectively. The second $K^{+}$ channel showed a conductance substate at $30{\sim}60%$ of the open state. Its current-voltage relation was linear in the range of $-80\;{\sim}\;+80\;mV$. The slope conductance of the substate and open-state were 40 and 144 pS in 0.2 M KCl, respectively. The channel was highly selective for $K^{+}$ over Cl. The open-state probability was weakly voltage-dependent (e-fold change per 35 mV. The lifetime distributions of open- and closed-states were fitted with two exponentials and the major gating occurred slowly at several hundred milliseconds. Based on the above results, we think the second type of $K^{+}$ channel is the sarcoplasmic reticulum $K^{+}$ (SRK) channel. In addition, both types of channel were also incorporated into the lipids extracted from the skeletal muscle. The channel properties recorded in the bilayers termed from synthetic and extracted lipids were qualitatively similar. Our data indicate that BK and SRK channels are rich in the skeletal muscle and their properties and regulation could be effectively studied in planar lipid bilayer.

• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.24-28
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• 2003

There is evidence to suggest that cranberry juice supplements improve the health of the urinary tract by inhibiting the binding of fimbriated uropathogenic E. coli to the bladder mucosa. In patients with neurogenic bladders, urinary tract infections (UTI) are particularly common and often poorly managed by antibiotic treatment. A double-blind, randomized, placebo-controlled trial was undertaken on 29 geriatric and spinal cord injured patients with dysfunctional bladders. They received three times daily at mealtimes a 4 oz bottle of cranberry juice (Ocean Spray Cranberries, USA) or a specially prepared synthetic placebo drink. Two episodes of UTI arose in week one of cranberry intake and none thereafter, compared to four episodes of UTI in 4 placebo patients in weeks four, six and 10. Mean bacterial adhesion counts on bladder cells of the patients rose during the first month of treatment in 71 % of the placebo patients compared to only 31 % of cranberry patients (p < 0.001). The difference persisted to some extent for the second and third months. Bacterial adhesion levels correlated with culture findings (higher adhesion and higher viable counts in urine) (p < 0.001), positive leukocyte nitrite tests (136$\pm$131 bacteria per cell versus 52$\pm$86 in negative tests) (p < 0.001), and higher white blood cell counts (> 10) per high power field (126$\pm$125 versus 48$\pm$85 bacteria per cell) (p<0.001). E. coli was the most frequently isolated organism (40% samples) followed by K. pneumoniae (17%) and a number of other uropathogens. Group B Streptococci, and coagulase negative Staphylococcus were recovered from urine in 4 samples but were not associated with any red blood cell presence. The daily intake of cranberry juice, in amounts which are not detrimental to long term compliance, appeared to have a role in reducing the risk of bladder colonization and infection in a highly susceptible patient population.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.531-536
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• 2004

In fracture treatment with external fixators, the inter-fragmentary movements at the fracture site affect the fracture healing process, and these movements are highly related to the stiffness of external fixation systems. Therefore, in order to provide the optimal fracture healing at the fracture site, it is essential to understand the relationship between the stiffness and the system configurations in external fixation system. In this study we investigated the influences of system configuration parameters on the stiffness in the finite element analysis of an external fixation system of a long bone. The system alignment, the geometric and the material non-linearity of the pin, the joint stiffness and the callus formation were considered in the finite element model. In the first, the system stiffness of the developed finite element model was compared with the experiment data for model validation. The consideration of the joint stiffness and nonlinearity of the model improved the system stiffness results. The joint stiffness, the non-alignment of the system decreased the system stiffness while the callus formation increased the system stiffness. The present results provided the biomechanical basis of rational guidelines for design improvements of external fixators and pre-op. planning to maximize the system stiffness in fracture surgery.

• Journal of Embryo Transfer
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• v.29 no.4
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• pp.333-337
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• 2014

To compensate for the critical shortage of human organs for allotransplantation, xenotransplantation studies using genetically modified pigs are being performed in Korea. Two types of pigs that are used are ${\alpha}1,3$-galactosyltransferase gene knockout (GalT KO) pigs and GalT KO+hCD46 (human complement regulatory protein) pigs. The present study measured the gestation time, birth weight, daily growth rate, and heart weight of both kinds of transgenic minipigs. The gestation period for both types of pigs was 117~119 days. There was no difference in the body weight of GalT KO (-/+) and GalT KO (-/-) piglets, but GalT KO+hCD46 ($-^{hCD46+}/+$) pigs were significantly heavier at birth than were GalT KO+hCD46 ($-^{hCD46+}/-^{hCD46+}$) pigs. During the first 10 weeks of life, the daily weight gain of GalT KO+hCD46 ($-^{hCD46+}/-^{CD46+}$) piglets, which are considered the optimal type for xenotransplantation, was 0.19 kg. The weight of hearts from GalT KO piglets up to two months of age was affected more by body weight than by age. Transgenic pigs showed no differences in gestation period or reproductive ability compared with normal pigs. These results comprise basic data that may be used in xenotransplantation studies and transgenic animal production in Korea.

• Proceedings of the KOSOMBE Conference
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• v.1993 no.11
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• pp.89-92
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• 1993

In this article, we present and analyze the results of the three consecutive in vivo experiments of the LVAD to evaluate the function of the LVAD and the adverse effects on living animals. We applied the LVAD consecutively to three mongrel dogs and the circulation of the blood was assisted under the anesthesia. We used in general both the asynchronous mode and the synchronous mode to drive the LVAD. During the experiments we monitored the dogs with a polygraph to evaluate the function of the LVAD and the additional effects on the natural hearts. We also examined several clinical pathologic tests in order to see the effects of the LVAD to the red blood cells and the other internal organs. The dogs survived for two to there days. The LVAD assisted the circulatory system at the maximum assist flow rate of 3.0 1/min. Although the red blood cells of the dogs had mechanical damages by the LVAD to result in the hemolysis, the degree of the hemolysis was not so high and the damages caused by the hemolysis on the dogs were not serious. The myocardium of the first dog was gradually worsened and eventually failed. The damage of the myocardium was due to the asynchronous driving mode of the LVAD. The other organs did not have serious damages due to the application of the LVAD. The main purpose of this paper is to evaluate the results of the in vivo experiments of the LVAD and to find better ways to the application of the LVAD to human beings.

• Journal of Veterinary Clinics
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• v.19 no.3
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• pp.299-302
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• 2002

Selectins are differentially expressed carbohydrate binding proteins involved in the initiation of tissue inflammation by mediating the rolling and tethering of leukocytes on the vascular endothelium. This primary event in initiation of inflammation, as occurs during reperfusion injury, can be therapeutically targeted using selectin inhibitors, which generally block binding of sLex to E-, P-, and L-selectins. The objective of this study was to determine the role of selectins in renal ischemia/reperfusion injury after kidney transplantation. Canine kidneys were subjected to 60-min warm ischemia, flushed with UW solution, cold stored for 24 h, and autotransplanted into the nephrectomized donor. Renal autografts were monitored for 7 days by serum creatinine in the first study and by histology and myeloperoxidase activity after 4-hour reperfusion in the second study. In each study, one group of animals received TBC1269 (selectin inhibitor) and the other received saline vehicle. Serum creatinine rose quickly after transplantation and was not different between the groups. TBC1269 abolished a reperfusion-induced 2-fold increase in renal cortex neutrophil infiltration and improved histologic signs of ischemia after 4 hours of reperfusion. Selectin blockade does not improve the course of injury caused by warm renal ischemia. A minor benefit associated with the inhibition of early inflammation during reperfusion after kidney transplantation seems to occur.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.315-319
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• 2007

Transgastric endoscopic cholecystectomy was successfully accomplished in a 1-year-old, 15 kg, female, mongrel dog. Single-working channel flexible gastric endoscope was used with the aid of one abdominal laparoscopic port. Gastrotomy was performed using endoscopic needle knife at the ventral antral region. Through the gastric incision endoscope was advanced and retroflexed for the visualization of gallbladder. For the better exposure of surgical field, gentle traction was applied at the fundus of the gallbladder using laparoscopic grasping forceps. Cystic duct and artery was ligated using endoclips. After transecting the duct and artery, gallbladder was dissected using endoscopic coagulating grasping forceps and needle knife. Resected gallbladder was retrieved through the mouth and gastric incision site was sutured using endoclips. There was no evidence of bile leakage or stomach leakage on postoperative day (POD) 3. On POD 16, gastric endoscopy and laparoscopy was performed. Gastric endoscopy revealed complete adhesion of incision site. The content of the peritoneum appeared healthy, with no sign of infection, bile staining, or organ injury. The omentum was adhered over resected gallbladder fossa and the serosal surface of gastrotomy site. This is the first report of NOTES cholecystectomy in the dog and provides new concept of cholecystectomy of the dog.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup1
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• pp.79-84
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• 2001

To investigate contributory factors of CSF shunt failure, 237 patients, who underwent shunt placement from January 1995 to December 1998 at our hospital, were reviewed retrospectively. The causes of the hydrocephalus were tumor, hemorrhage, infection, congenital anomaly, normal pressure hydrocephalus, trauma and others. One hundred nine revisions of CSF shunting were done during follow up periods. The causes of shunt revisions were mechanical obstruction, malposition, infection and others. The contributory factors of CSF shunt failure and shunt survival rate were analyzed using SPSS. The shunt survival rate at 1, 2 and 3 years after procedure was 77.1%, 75.4%, 74.1% respectively. In the young age group below 10 years old, postinfectous hydrocephalus was the most common high risk factor for shunt revision. In conclusion, the most shunt failures developed in the first year after surgery and the age and causes of the hydrocephalus were major determinant factors of shunt revision.

• Journal of Korean Neurosurgical Society
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• v.56 no.3
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• pp.175-187
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• 2014

The purpose of this clinical practice guideline (CPG) is to provide current and comprehensive recommendations for the medical and surgical management of primary intracerebral hemorrhage (ICH). Since the release of the first Korean CPGs for stroke, evidence has been accumulated in the management of ICH, such as intracranial pressure control and minimally invasive surgery, and it needs to be reflected in the updated version. The Quality Control Committee at the Korean Society of cerebrovascular Surgeons and the Writing Group at the Clinical Research Center for Stroke (CRCS) systematically reviewed relevant literature and major published guidelines between June 2007 and June 2013. Based on the published evidence, recommendations were synthesized, and the level of evidence and the grade of the recommendation were determined using the methods adapted from CRCS. A draft guideline was scrutinized by expert peer reviewers and also discussed at an expert consensus meeting until final agreement was achieved. CPGs based on scientific evidence are presented for the medical and surgical management of patients presenting with primary ICH. This CPG describes the current pertinent recommendations and suggests Korean recommendations for the medical and surgical management of a patient with primary ICH.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.3
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• pp.143-152
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• 2019

Purpose: The aim of this study is to investigate the characteristics of patients and teeth referred to a university dental hospital for endodontic problem. Materials and Methods: From January, 2017 to December, 2018, patients who were referred to a university dental hospital for endodontic problem were collected from clinical records. A total of 1171 patient records were analyzed. The status of the referred teeth was divided into three groups according to whether they were treated endodontically based on radiographs and clinical records at the time of referred visit. Results: 69.9% of the referred teeth were maxillary and mandibular first and second molars. The average time from referral to actual visit is 9.03 days and 65.6% of the case referred with referring letter. The most primary reasons of referral were persistent clinical symptom (pain, swelling, and sinus tract) (37.9%), diagnosis difficulty (16.7%), blockage of canal space (13.8%) and difficult tooth anatomy (11.4%). In the case of referral before endodontic treatment, the most primary reason of referral was failure to make a proper diagnosis. If the teeth were referred in the middle of endodontic treatment, the most primary reason of referral was persistent clinical symptom and blockage of canal space. In the case of referral after root canal filling, the most primary reason of referral was persistent clinical symptom. Conclusion: In the case of molars, the rate of persistent clinical symptom and blockage of canal space were the most primary reason of referral, and the rate of apical surgery and management of trauma was high in the case of anterior teeth.