• Journal of Science and Technology Studies
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• v.17 no.1
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• pp.71-115
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• 2017

In 1953, theoretical physicist George Gamow attempted to explain the process of protein synthesis by hypothesizing that the base sequence of DNA encodes a protein's amino acid sequence and, in response, proposed the nucleic acid-protein information transfer model, which he dubbed the "diamond code." After expressing interest in discussing the daring hypothesis, contemporary biologists, including James Watson, Francis Crick, Sydney Brenner, and Gunther Stent, were soon invited to join the RNA Tie Club, an informal research group that would also count biologists and various researchers in physics, mathematics, and computer engineering among its members. In examining the club's formation, growth, and decline in multidisciplinary research on deciphering the genetic code in the 1950s, this paper first investigates whether Gamow's idiosyncratic approach could be adopted as a collaborative research forum among contemporary biologists. Second, it explores how the RNA Tie Club's research agenda could have been expanded to other relevant research topics needing multidisciplinary approach? Third, it asks why and how the RNA Tie Club dissolved in the late 1950s. In answering those questions, this paper shows that analyses on the intersymbol correlation of the overlapping code functioned to integrate diverse approaches, including sequence decoding and statistical analysis, in research on the genetic code. As those analyses reveal, the peculiar approaches of the RNA Tie Club could be regarded as a useful method for biological research. The paper also concludes that the RNA Tie Club dissolved in the late 1950s due to the disappearance of the collaborative research agenda when the overlapping code hypothesis was abandoned.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.5
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• pp.402-407
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• 2010

Introduction: The planning of implant surgery is an important factor for the implant prosthesis. Stereolithographic (SLA) surgical stents based on a computer simulation are quite helpful for clinicians to perform the surgery as planned. Although many clinical and technical trials have been performed for computed tomography (CT)-guided implant stents to improve the surgical procedures and prosthetic treatment, there are still many problems to solve. We developed a system of a surgical guide based on 3 dimensional (3D) CT for implant therapy and achieved satisfactory results in the terms of planning and operation. Materials and Methods: Fifteen patients were selected and 30 implant fixtures were installed. The preoperative CT data for surgical planning were prepared after obtaining informed consent. Surgical planning was performed using the simulation program, Ondemend3D In2Guide. The stents were fabricated based on the simulation data containing information of the residual bone, the location of the nerve, and the expected design of the prostheses. After surgery with these customized stents, the accuracy and reproducibility of implant surgery were evaluated based on the computer simulation. The data of postoperative CT were used to confirm this system using the image fusion technique and compare the implant fixtures between the planned and implanted. Results: The mean error was 1.18 (${\pm}0.73$) mm at the occlusal center, 1.23 (${\pm}0.67$) mm at the apical center, and the axis error between the two fixtures was $3.25^{\circ}C$ (${\pm}3.00$). These stents showed superior accuracy in maxilla cases. The lateral side error at the apical center was significantly different from the error at the occlusal center but there were no significant differences between the premolars, 1st molars and 2nd molars. Conclusion: SLA surgical stents based on a computer simulation have the satisfactory accuracy and are expected to be useful for accurate planning and surgery if some errors can be improved.

• Journal of Periodontal and Implant Science
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• v.23 no.1
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• pp.109-126
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• 1993

Refractory periodontitis manifest progressive attachment loss in a rapid and unrelenting manner regardless of the type or frequency of therapy applied. The purpose of this study was ta evaluate the relation between the level of cytokines in GCF and periodontopathic microflora with disease activity of refractory periodontitis. Selection of patients with refractory periodontitis (7 males, 3 females) were made by long term clinical observation including conventional clinical history and parameters. Teeth that showed pocket depth greater than 6mm were selected as sample teeth. Subjects were examined at baseline and after 3 months. Prior to baseline test, individual acrylic stent was fabricated. Reference grooves were made on each sample tooth site. Pocket depth and attachment loss were measured by Florida Probe. Gingival index was measured at 4 sites each sample teeth. Disease activity was defined as attachment loss of ${\ge}$ 2.1mm, as determined by sequential probing and tolerance method. The pattern and amount of alveolar bone resorption was observed with quantitative digital subtraction image processing radiography. Morphological analysis of subgingival bacteria was taken by phase contrast microscopy. Predominant cultivable bacterial distribution and frequency were compared between disease-active and disease-inactive site using immunofluorescence microscopy and selective microbial culturing. Levels of $interleukin-l{\beta}$, 2, 4, 6 and $TNF-{\alpha}$ in GCF and blood serum sample were quantified by ELISA. In active sites, P. intermedia was significantly increased to compare with inactive site. $IL-1{\beta}$, IL-2, IL-6 and $TNF-{\alpha}$ in GCF were increased in active sites and IL-2 in serum was increased in active patients significantly. Alveolar bone loss in active site was correlated with $IL-1{\beta}$, IL-2 in GCF. And loss of attachment in active site was correlated with IL-2 in GCF. These results demonstrate that IL-2 in serum, $IL-1{\beta}$, IL-2, IL-6 and $TNF-{\alpha}$ in GCF, P, intermedia might be used as possible predictors of disease activity in refractory periodontitis before it is clinically expressed as attachment loss and quantitative alveolar bone change.

• Journal of Trauma and Injury
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• v.29 no.3
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• pp.93-97
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• 2016

Hepatic duct confluence injury, which is developed by blunt abdominal trauma, is rare. Conventionally, bile duct injury was treated by surgical intervention. In recent decades, however, there had been an increase in radiologic or endoscopic intervention to treat bile duct injury. In a hemodynamically stable patient, endoscopic intervention is considered as the first-line treatment for bile duct injury. A 40 year-old man was transferred to the emergency department of ${\bigcirc}{\bigcirc}$ trauma center after multiple blunt injuries. Contrast-enhanced abdominal computed tomography performed in another hospital showed a liver laceration with active arterial bleeding, fracture of the sacrum and left inferior pubic ramus, and intraperitoneal bladder rupture. The patient presented with hemorrhagic shock because of intra-peritoneal hemorrhage. After resuscitation, angiographic intervention was performed. After angiographic embolization of the liver laceration, emergency laparotomy was performed to repair the bladder injury. However, there was no evidence of bile duct injury on initial laparotomy. On post-trauma day (PTD) 4, the color of intra-abdominal drainage of the patient changed to a greenish hue; bile leakage was revealed on magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP). Bile leakage was detected near the hepatic duct confluence; therefore, a biliary stent was placed into the left hepatic duct. On PTD 37, contrast leakage was still detected but both hepatic ducts were delineated on the second ERCP. Stents were placed into the right and left hepatic ducts. On PTD 71, a third ERCP revealed no contrast leakage; therefore, all stents were removed after 2 weeks (PTD 85). ERCP and biliary stenting could be effective treatment options for hemodynamically stable patients after blunt trauma.

• Clinical and Experimental Pediatrics
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• v.61 no.7
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• pp.210-216
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• 2018

Purpose: The present study aimed to evaluate progression and prognosis according to the palliation method used in neonates and early infants aged 3 months or younger who were diagnosed with pulmonary atresia with ventricular septal defect (PA VSD) or tetralogy of Fallot (TOF) with severe pulmonary stenosis (PS) in a single tertiary hospital over a period of 12 years. Methods: Twenty with PA VSD and 9 with TOF and severe PS needed initial palliation. Reintervention after initial palliation, complete repair, and progress were reviewed retrospectively. Results: Among 29 patients, 14 patients underwent right ventricle to pulmonary artery (RV-PA) connection, 11 palliative BT shunt, 2 central shunt, and 2 ductal stent insertion. Median age at the initial palliation was 13 days (1-98 days). Additional procedure for pulmonary blood flow was required in 5 patients; 4 additional BT shunt operations and 1 RV-PA connection. There were 2 early deaths among patients with RV-PA connection, one from RV failure and the other from severe infection. Finally, 25 patients (86%) had a complete repair. Median age of total correction was 12 months (range, 2-31 months). At last follow-up, 2 patients had required reintervention after total correction; 1 conduit replacement and 1 right ventricular outflow tract (RVOT) patch enlargements. Conclusion: For initial palliation of patients with PA VSD or TOF with severe PS, not only shunt operation but also RV-PA connection approach can provide an acceptable outcome. To select the most proper surgical strategy, we recommend thorough evaluation of cardiac anomalies such as RVOT and PA morphologies and consideration of the patient's condition.

• Journal of Korean Neurosurgical Society
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• v.63 no.5
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• pp.590-597
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• 2020

Objective : Covered stenting is an optional strategy for traumatic carotid pseudoaneurysm, especially in malignant conditions of potential rupture, but the long-term outcomes are not clear. Our aim was to determine if covered stenting is an effective option for traumatic carotid pseudoaneurysm with promising long-term outcomes. Methods : Self-expanding Viabahn and balloon-expandable Willis covered stents were separately implanted for extra- and intracranial traumatic carotid pseudoaneurysm. The covered stent was placed across the distal and proximal pseudoaneurysm leakage under roadmap guidance. Procedural success was defined as technical success (complete exclusion of the pseudoaneurysm and patency of the parent artery) without a primary end point (any stroke or death within 30 days after the procedure). Long-term outcomes were evaluated as ischemic stroke in the territory of the qualifying artery by clinical follow-up through outpatient or telephone consultation and as the exclusion of the pseudoaneurysm and patency of the parent artery by imaging follow-up through angiography. Results : Five patients with traumatic carotid pseudoaneurysm who underwent covered stenting were enrolled. The procedural success rate was 100%. No ischemic stroke in the territory of the qualifying artery was recorded in any of the five patients during a mean clinical follow-up of 44±16 months. Complete exclusion of the pseudoaneurysm and patency of the parent artery were maintained in all five patients during a mean imaging follow-up of 39±16 months. Conclusion : Satisfactory procedural and long-term outcomes were obtained, suggesting that covered stenting is an effective option for traumatic carotid pseudoaneurysm.

• Journal of Chest Surgery
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• v.32 no.6
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• pp.532-535
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• 1999

Background: The purpose of this study was to evaluate and analyze the surgical techniques and postoperative complications in patients undergoing operations for descending thoracic aortic aneurysms. Material and Method: The data of 22 major operations between March 1987 and August 1997 were retrospectively reviewed. Result: There were 18 men and 4 women with a mean age of 49 years (range 33 years to 82 years). The cause of the aneurysm was aortic dissection in 13 patients, atherosclerosis in 3, mycotic in 3, trauma in 2 and uncertain in 1. The operative techniques were resection and graft replacement in 16, axillofemoral bypass graft in 2, femorofemoral bypass graft in 2, exclusion, aneurysmorrhaphy in 1 and transfemoral stent insertion in 1. During the operation, 16 cases were performed under total aortic clamp. Among the 16 patients, femorofemoral bypass was used in 14 cases and previously made shunt in 2 cases. The mean total aortic clamp time was 91 minutes and the mean extracorporeal circulation time was 116 minutes. One death occurred in an excluded patient on the 52 postoperative day due to a rupture of the aneurysm. Postoperative complications were paraplegia in 1 case, acute renal failure in 1 case and acute respiratory failure in 1 case. Conclusion: Although surgical treatment of the descending thoracic aneurysm has many postoperative complications, good surgical results can be achieved with a proper patient selection and fine surgical techniques.

• The Journal of the Korean dental association
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• v.56 no.5
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• pp.263-276
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• 2018

Long-term survival and prognosis of narrow-diameter implants have been reported to be adequate to consider them a safe method for treating a deficient alveolar ridge. The objective of this study was to perform case report of narrow-diameter implants with a trapezoid-shape in anterior teeth alveolar bone. A 50-year-old male patient presented with discomfort due to mobility of all of the maxillary teeth and mandibular incisors. Due to destruction of alveolar bone, four anterior mandibular teeth were extracted. Soft tissue healing was allowed for approximately 3 months after the extraction, and a new design of implant placement was planned for the mandibular incisor area, followed by clinical and radiological evaluation. Implant placement was determined using an R2GATE surgical stent. The stability of the implants was assessed by ISQ measurements at the first and second implant surgery and after prosthetic placement. At 1 and 3 months and 1 year after implantation of the prosthesis, clinical and radiological examinations were performed. Another 50-year-old male patient presented with discomfort due to mobility of the mandibular central incisors. For the same reason as in the first patient, implant placement was carried out in the same way after extraction. ISQ measurements and clinical and radiological examinations were performed as in the previous case. In these two clinical cases, 12 months of follow-up revealed that the implant remained stable without inflammation or additional bone loss, and there was no discomfort to the patient. In conclusion, computer-guided implant surgery was used to place an implant in an optimal position considering the upper prosthesis. A new design of a narrow-diameter implant with a trapezoid-shape into anterior mandibular alveolar bone is a less invasive treatment method and is based on the contour of the deficient alveolar ridge. Through all of these procedures, we were able to reduce the number of traumas during surgery, reduce the operation time and total treatment period, and provide patients with more comfortable treatment.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.33-38
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• 2013

Occlusal plane is a sagittal expression of dental arch form, and it composes the shape of occlusion, which is one of the most important elements of Maxillo-oral system. In this case, vertical, horizontal coordinates of bionic-median-sagittal plane was produced in articulator, and to achieve relation of left and right position of upper, lower teeth and deficits in alveola, Shilla system was used to reconstruct occlusal plane. In this case, a 41 year-old male patient visited for fracture of 10 unit metal-ceramic fixed partial denture of upper anterior teeth and for overall treatment. Clinical, radiographical, model examination was held, full mouth rehabilitation was achieved by placing dental implant. Maxillo-oral relation was recorded using Gothic arch Tracer complex and were mounted. And for the next step, we estimated original occlusal plane using Shilla system. After analysis we produced diagnosis wax pattern. On the basis of this, radiography stent was manufactured and dental implant was placed, and temporary prosthesis was made by using diagnosis wax pattern. Cross mounting and anterior guiding table were performed in order to reproduce temporary restoration morphology and bite pattern, followed by final restoration made of all ceramic crown with zirconia coping. As stated above, appropriately esthetic and functional results can be seen in using Shilla system in diagnosis and treatment procedure of full mouth rehabilitation patient.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.243-247
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• 2013

Introduction: Surgical treatment of subclavian artery (SA) injury is challenging because approaching the lesion directly and clamping the proximal artery is difficult. This can be overcome by using an endovascular technique. Case 1: A 37-year-old male was drawn into the concrete mixer truck. He had a right SA injury with multiple traumatic injuries: an open fracture of the right leg with posterior tibial artery (PTA) injury, a right hemothorax, and fractures of the clavicle, scapula, ribs, cervical spine and nasal bone. The injury severity score (ISS) was 27. Computed tomography (CT) showed a 30-mm-length thrombotic occlusion in the right SA, which was 15 mm distal to the vertebral artery (VA). A self-expandable stent($8mm{\times}40mm$ in size) was deployed through the right femoral artery while preserving VA flow, and the radial pulse was palpable after deployment. Other operations were performed sequentially. He had a viable right arm during a 13-month follow-up period. Case 2: A 25-year-old male was admitted to our hospital due to a motorcycle accident. The ISS was 34 because of a hemothorax and open fractures of the mandible and the left hand. Intraoperative angiography was done through a right femoral artery puncture. Contrast extravasation of the SA was detected just outside the left rib cage. After balloon catheter had been inflated just proximal to the bleeding site, direct surgical exploration was performed through infraclavicular skin incision. The transected SA was identified, and an interposition graft was performed using a saphenous vein graft. Other operations were performed sequentially. He had a viable left arm during a 15-month follow-up period. Conclusion: The challenge of repairing an SA injury can be overcome by using an endovascular approach.