• Title/Summary/Keyword: membrane replacement

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Recent Trends and Future Perspectives of the Magnesium Recovery based on Electrolysis (전해 기반 마그네슘 회수 기술의 관련 동향 및 향후 전망)

  • Sang-hun Lee
    • Resources Recycling
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    • v.33 no.2
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    • pp.16-23
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    • 2024
  • The electrolysis for extracting magnesium from seawater or brine primarily involves recovery of magnesium via precipitation as the form of magnesium hydroxide. The technology is classified into cation-exchange membranes (CEM), anion-exchange (AEM) membranes, electrodialysis, and membraneless methods. Recent research has focused on enhancing the efficiency and selectivity of magnesium recovery from seawater or brine containing magnesium, with expectations of effective magnesium recovery even with normal seawater. In a future, the optimization of the selective and efficient recovery of magnesium and various valuable substances through long-term operation of scaled-up systems is crucial with enhancing economic and environmental viability. It is essential to realistically estimate operational costs considering the membrane's lifespan and replacement cycle. Also, detailed and practical process models should be developed based on monitoring data on various factors.

Prognosis in the Patients with Prolonged Extracorporeal Membrane Oxygenation

  • Kim, Tae-Hun;Lim, Cheong;Park, Il;Kim, Dong-Jin;Jung, Yo-Chun;Park, Kay-Hyun
    • Journal of Chest Surgery
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    • v.45 no.4
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    • pp.236-241
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    • 2012
  • Background: Prolonged usage of extracorporeal membrane oxygenation (ECMO) may induce multi-organ failure. This study is aimed to evaluate prognostic factors in the patients with ECMO. Also, the prognosis of ECMO with Kidney Injury Network Scoring system is studied. Materials and Methods: From May 2005 to July 2011, 172 cases of ECMO were performed. The cases of perioperative use of ECMO were excluded. Renal failure patient and younger than 15 years old one were also excluded. As a result, 26 cases were enrolled in this study. Male patients were 15 (57.7%), and mean age was $56.57{\pm}17.03$ years old. Demographic data, ECMO parameters, weaning from ECMO, and application of continuous renal replacement therapy are collected and Acute Kidney Injury Network (AKIN) scores were evaluated just before ECMO and day 1, day 2 during application of ECMO. Results: Venoarterial ECMO was applied in 22 cases (84.6%). The reasons for applications of ECMO were cardiac origin in 21 (80.8%), acute respiratory distress syndrome in 4, and septic shock in 1 case. Successful weaning from ECMO was achieved in 15 cases (57.7%), and survival discharge rate was 9 cases (34.6%). Mean duration of application of ECMO was $111.39{\pm}54.06$ hours. In univariate analysis, myocarditis was independent risk factors on weaning failure. Using the receiver operating characteristic curve, level of hemoglobin on 24 hours after ECMO, and base excess on 48 hours after ECMO were showed more than 0.7. AKIN score was not matched the prognosis of the patients with ECMO. Conclusion: In our study, the prognosis of the patients with myocarditis was poor. Hemoglobin level at first 24 hours, and degree of acidosis at 48 hours were useful methods in relating with prognosis of ECMO. AKIN scoring system was not related with the prognosis of the patients. Further study for prognosis and organ injury during application ECMO may be needed.

Clinical Application of Radial Head Prosthesis (요골두 치환술의 임상적 적용)

  • Moon, Jun-Gyu
    • Clinics in Shoulder and Elbow
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    • v.14 no.1
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    • pp.140-145
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    • 2011
  • Purpose: Installing a radial head prosthesis has developed into a reliable procedure to replace the native radial head for treating unreconstructible radial head fracture when this is associated with an unstable elbow or forearm. A variety of implants have been developed and these are now commercially available. This article reviews the literature related to the indications, the available implants and the surgical techniques of radial head replacement arthroplasty. Materials and Methods: The main indication for a metallic radial head prosthesis is a comminuted fracture that is not amenable to reconstruction, and particularly if it is associated with complex elbow injuries. Excision of the radial head should be avoided in the presence of combined injured ligaments or interosseous membrane injury. Three different implants are available in Korea, including the bipolar, press fit monopolar and loose fit monopolar radial head prostheses. A primary technical goal of radial head arthroplasty is the insertion of an implant that closely replicates the native radial head. The major pitfall when using a metallic radial head prosthesis is the insertion of a longer implant, which results in overstuffing of the radiocapitellar joint. Results and Conclusion: Satisfactory clinical results can be anticipated when a radial head prosthesis is used for the correct indications and when a systemic approach is undertaken to ensure proper sizing. For the future studies, we need data regarding the long term outcomes and comparison of the various types of prostheses.

Patch Graft of the Canine Esophagus (식도이식에 관한 실험적 연구)

  • Ha, Gye-Sik
    • Journal of Chest Surgery
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    • v.2 no.2
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    • pp.167-167
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    • 1969
  • Two groups of esophagus graft were done in canine esophagus in 34 adult mongrel dogs. For the first group segmental replacement graft was done with fresh autologous pericardium tube, and for the second, patch graft was done utilizing fresh autologous pericardium, fresh homologous pericardium,and dacron piece. All eight dogs in the first segmental replacement graft group died 2 to 5 days after operation with severe empyema caused by anastomosis disruption. Among 26 patch graft dogs 2 died during operation and 7 died 13 to 18 days after operation. For the 17 long-term patch grafted survivors esophagography and postoperative weight check were done. Postoperative stool was collected and examined for dacron patch excretion. One, two, three, and four months postoperative long-term survivors were sacrificed to obtain specimens in each group respectively and the following observations were made.I. Survival; Autologous pericardium patch group showed no mortality but in homologous pericardium and dacron patch group only two thirds were long-term survivors. II. Postoperative swallowing; There was no case which demonstrated postoperative dysphagia. About half of the cases showed postoperative weight increase and in only 3 cases weight decrease followed operation. III. Dacron patch was excreted in the stool 8 to 23 days after operation. Animals which excreted dacron patch up to 9 days after operation all died of empyema due to anastomosis disruption.IV. Postoperative esophagogram; All esophagograms in each group showed no leakage of barium, no passage disturbances and no remarkable stenotic signs.V. Morphological findings; [A] Macroscopical findings; In one month group specimens of each group dense adhesion with surrounding structures was noted and luminal surface was smooth with contraction of the patched area. In two month groups anastomosis sutures were still exposed but patched area showed lesser abnormality. In three to four months groups sutures were covered completely and patched area showed only very slight signs of contraction. [B] Microscopic findings; In one month group luminal surface of the replaced tissue [transplanted tissue] showed almost complete epithelial covering that is composed of several layers of squamous cells with no evidence of keratinization. Basement membrane was also well distinct throughout. Slight to minimal inflammatory cells comprising of large mononuclears, lymphocytes and plasma cells were observed in the subepithelial fibrous stroma consisted entirely of loose fibrous tissue containing many newly formed capillaries and fibroblastic proliferation. Scattered suture granulomas were found, few of which became acutely inflamed. In two months group repairing process progressed with lesser degree of inflammatory cell infiltration and young capillary proliferation. Fibrous tissue was more matured showing even focal collagenization.Suture granuloma persisted but with lesser reactive changes. Epithelial covering was that of a mature non-keratinizing stratified squamous epithelium. In three and four months groups the replaced area showed essentially similar histological findings. However, subepithelial stroma still consisted entirely of connective tissue without evidence of smooth muscle regeneration. In this group, inflammatory cell infiltration was minimal or negligible. Among these patch materials autologous pericardium group showed the most satisfactory repairing process.The above mentioned results may signify the feasibility of autogenous pericardium patch graft in clinical esophageal surgery.

Patch Graft of the Canine Esophagus (식도이식에 관한 실험적 연구)

  • 하계식
    • Journal of Chest Surgery
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    • v.2 no.2
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    • pp.168-186
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    • 1969
  • Two groups of esophagus graft were done in canine esophagus in 34 adult mongrel dogs. For the first group segmental replacement graft was done with fresh autologous pericardium tube, and for the second, patch graft was done utilizing fresh autologous pericardium, fresh homologous pericardium,and dacron piece. All eight dogs in the first segmental replacement graft group died 2 to 5 days after operation with severe empyema caused by anastomosis disruption. Among 26 patch graft dogs 2 died during operation and 7 died 13 to 18 days after operation. For the 17 long-term patch grafted survivors esophagography and postoperative weight check were done. Postoperative stool was collected and examined for dacron patch excretion. One, two, three, and four months postoperative long-term survivors were sacrificed to obtain specimens in each group respectively and the following observations were made. I. Survival; Autologous pericardium patch group showed no mortality but in homologous pericardium and dacron patch group only two thirds were long-term survivors. II. Postoperative swallowing; There was no case which demonstrated postoperative dysphagia. About half of the cases showed postoperative weight increase and in only 3 cases weight decrease followed operation. III. Dacron patch was excreted in the stool 8 to 23 days after operation. Animals which excreted dacron patch up to 9 days after operation all died of empyema due to anastomosis disruption. IV. Postoperative esophagogram; All esophagograms in each group showed no leakage of barium, no passage disturbances and no remarkable stenotic signs. V. Morphological findings; [A] Macroscopical findings; In one month group specimens of each group dense adhesion with surrounding structures was noted and luminal surface was smooth with contraction of the patched area. In two month groups anastomosis sutures were still exposed but patched area showed lesser abnormality. In three to four months groups sutures were covered completely and patched area showed only very slight signs of contraction. [B] Microscopic findings; In one month group luminal surface of the replaced tissue [transplanted tissue] showed almost complete epithelial covering that is composed of several layers of squamous cells with no evidence of keratinization. Basement membrane was also well distinct throughout. Slight to minimal inflammatory cells comprising of large mononuclears, lymphocytes and plasma cells were observed in the subepithelial fibrous stroma consisted entirely of loose fibrous tissue containing many newly formed capillaries and fibroblastic proliferation. Scattered suture granulomas were found, few of which became acutely inflamed. In two months group repairing process progressed with lesser degree of inflammatory cell infiltration and young capillary proliferation. Fibrous tissue was more matured showing even focal collagenization. Suture granuloma persisted but with lesser reactive changes. Epithelial covering was that of a mature non-keratinizing stratified squamous epithelium. In three and four months groups the replaced area showed essentially similar histological findings. However, subepithelial stroma still consisted entirely of connective tissue without evidence of smooth muscle regeneration. In this group, inflammatory cell infiltration was minimal or negligible. Among these patch materials autologous pericardium group showed the most satisfactory repairing process. The above mentioned results may signify the feasibility of autogenous pericardium patch graft in clinical esophageal surgery.

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D99 Type I Signal Peptidase Implicated Stabilizing the Protein Structure (Type I 신호펩디드 가수분해효소에 존재하는 D99 아미노산 잔기의 구조적 역할 가능성)

  • Sung, Meesook;Eunyoung Han;Lee, Hoyoung
    • Microbiology and Biotechnology Letters
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    • v.31 no.2
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    • pp.140-144
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    • 2003
  • Type Ⅰ signal peptidase is an integral membrane protein that functions to cleave signal peptides from secreted and membrane proteins. The enzyme serves as a potential target for the development of novel antibacterial agents due to its unique physiological properties. Despite being one of the best characterized enzymes, the catalysis of Type Ⅰ signal peptidase still remains controversy over the catalytic serine/lysine dyad mechanism. It appears that the dyad proteases are generally less efficient than the prototypical serine/histidine/aspartic acid triad found in most enzymes, although Type Ⅰ signal peptidase is an exception to this rule. In this paper, we have proposed that Type Ⅰ signal peptidase may act as the serine/lysine/aspartic acid triad cataltytic mechanism. Therefore, the aspartic acid 99 residue in the E. coli signal peptidase was chosen and mutated to an alanine to see if there is any possible role of the aspartic acid in the catalytic function. Type Ⅰ signal peptidase D99A protein was inactive in vitro assay using the procoat synthesized by in vitro transcription translation. However, the mutant was active using a highly sensitive in vivo assay. Pulse-chase experiments show that the replacement of aspartic acid 99 with alanine results in a very unstable signal peptidase molecule. Therefore, we conclude that it is unlikely that the residue is directly involved in catalysis, but rather plays an important role in stabilizing the protein structure.

The cloning and characterization of the small GTP-binding Protein RacB in rice.

  • Jung, Young-Ho;Jaw, Nam-Soo
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.81.2-82
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    • 2003
  • Plants have evolved along with pathogens, and they have developed sophisticated defense systems against specific microorganisms to survive. G-protons are considered one of the upstream signaling components working as a key for the defense signal transduction pathway. For activation and inactivation of G-protein, GTP-biding proteins are involved. GTP -binding proteins are found in all organisms. Small GTP-binding proteins, having masses of 21 to 30kD, belong to a superfamily, often named the Ras supefamily because the founding members are encoded by human Ras genes initially discovered as cellular homologs of the viral ras oncogene. Members of this supefamily share several common structural features, including several guanine nucleotide binding domains and an effector binding domain. However, exhibiting a remarkable diversity in both structure and function. They are important molecular switches that cycle between the GDP-bound inactive form into the GTP-bound active form through GDP/GTP replacement. In addition, most GTP-binding proteins cycle between membrane-bound and cytosolic forms. such as the RAC family are cytosolic signal transduction proteins that often are involved in processing of extracellular stimuli. Plant RAC proteins are implicated in regulation of plant cell architecture secondary wall formation, meristem signaling, and defense against pathogens. But their molecular mechanisms and functions are not well known. We isolated a RacB homolog from rice to study its role of defense against pathogens. We introduced the constitutively active and the dominant negative forms of the GTP-hinging protein OsRacB into the wild type rice. The dominant negative foms are using two forms (full-sequence and specific RNA interference with RacB). Employing southern, and protein analysis, we examine to different things between the wild type and the transformed plant. And analyzing biolistic bombardment of onion epidermal cell with GFP-RacB fusion protein revealed association with the nucle.

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An Elderly Man with Fatal Respiratory Failure after Eating a Poisonous Mushroom Podostroma cornu-damae

  • Jang, Juah;Kim, Cheol-Hong;Yoo, Jun Jae;Kim, Mi Kang;Lee, Jae Eun;Lim, Ah Leum;Choi, Jeong-Hee;Hyun, In Gyu;Shim, Jung Weon;Shin, Ho-Seung;Han, Joungho;Seok, Soon Ja
    • Tuberculosis and Respiratory Diseases
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    • v.75 no.6
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    • pp.264-268
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    • 2013
  • A 73-year-old, previously healthy man presented with nausea, vomiting, diarrhea, dry mouth and febrile sensation 3 hours after eating boiled wild mushrooms. After admission, he showed progressive severe respiratory distress, pancytopenia, azotemia, hypotension, hypoxemia and consolidation of the entire left lung on chest radiography. With a preliminary diagnosis of necrotizing pneumonia, he underwent left pneumonectomy in order to remove all necrotic lung tissue. Lung histology showed extensive hemorrhagic necrosis, massive inflammatory cell infiltration, prominent proliferation of young fibroblasts and the formation of an early-stage hyaline membrane along the alveolar wall. Despite aggressive treatment, including mechanical ventilation, continuous renal replacement therapy and administration of granulocyte colony stimulating factor and broad spectrum antibiotics, he died on hospitalization day 13. Subsequently, the mushroom was identified as Podostroma cornu-damae. This is the first case of a histological evidence of lung involvement by Podostroma cornu-damae poisoning in Korea.

Clinical experience of open heart surgery -70 cases- (개심술 70예의 임상경험)

  • 조광현
    • Journal of Chest Surgery
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    • v.19 no.4
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    • pp.644-662
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    • 1986
  • Seventy cases of open heart surgery were performed in the department of Thoracic and Cardiovascular Surgery, Pusan Paik Hospital, Inje College, from Oct. 1985 to Oct. 1986. And the results were summarized as follows. 1. Among the 70 cases, there were 48 cases of congenital heart anomalies and 22 cases of acquired rheumatic valvular heart diseases. Age range of the congenital patients was 7 months to 31 years with the mean age of 10 years, and the acquired patients was 18 to 62 years with the mean age of 40 years. 2. The heart-lung machine used for cardiopulmonary bypass was Sarns 7000, 5-head roller pump, and the number and type of oxygenators were 5 of membrane type and 65 of bubble type. For all cases GIK [glucose-insulin-potassium] solution was used as cardioplegic solution for myocardial protection during operation. 3. Among the 48 congenital anomalies, there were 12 cases of ASD group, 29 of VSD group, 3 of ECD, 3 of TOF and one of PDA + MR, and to all of which the appropriate radical operations were applied. 4. Among the 22 acquired valvular diseases, there were 11 cases of mitral valve diseases [MS; 4, MSr; 3, MRs; 4], 3 cases of aortic valve diseases [AR:1, ARs;1, ASr;1], 4 cases of double valve diseases [MRs+TR; 3, MRs+ARs; 1] and 4 cases of triple valve diseases [MSr+ASr+TR; 3, MSr+Ar+TR; 1]. To all the diseased mitral and aortic valves, artificial valve replacement was applied except one [As], in which valve plication was applied. And to all the diseased tricuspid valve, DeVega annuloplasty was applied. 5. The number of replaced artificial valves were 29 in 25 patients [congenital; 3, acquire; 22]. In MVR, 6 of mechanical valves [St. Jude Medical valve; 6] and 15 of tissue valves [Carpentier-Edward valve; 11, lonescu-Shiley valve; 4] were used. In AVR, 6 of mechanical valves [St. Jude Medical valve; 6] and 2 of tissue valves [Carpentier-Edward valve; 2] were used. 6. Postoperative complications were occurred in 12 cases. Among them 11 cases were recovered with intensive cares, but one patient [VSD + Fistula of Valsalva sinus] was expired with low cardiac out put syndrome.

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A Case of Bronchocentric Granulomatosis Associated with Aspergillus (아스페르길루스와 연관된 기관지중심성 육아종증 1예)

  • Kim, Yang-Ki;Jun, Ki-Won;Kim, Chul;Kim, Ki-Up;Ki, Shin-Young;Uh, Soo-Taek;Kim, Yong-Hoon;Park, Chun-Sik
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.6
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    • pp.1290-1297
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    • 1998
  • Bronchocentric granulomatosis(BCG), first defined in 1973, consists of granulomatous replacement of bronchial mucous membrane, often with heavy eosinophilic reaction within and about the involved bronchi. Etiologic factors are from hypersensitivity reaction for aspergillus, most often from idiopathic form, and in others from being associated with mycobacterium, ecchinococcus, rheumatoid disease, ankylosing spodylitis, and glomerulonephritis. Diagnosis is responsible only for pathologic findings and, in many cases, is confirmed in postoperative findings with misleading for tumor, tuberculosis, infectious or Wegener's granulomatosis. We report a case of bronchocentric granulomatosis associated with aspergillus.

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