• Journal of Biomedical Engineering Research
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• v.33 no.3
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• pp.148-154
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• 2012

Hemorrhagic shock is a primary cause of deaths resulting from injury in the world. Although many studies have tried to diagnose accurately hemorrhagic shock in the early stage, such attempts were not successful due to compensatory mechanisms of humans. The objective of this study was to construct a survival prediction model of rats in acute hemorrhagic shock using a random forest (RF) model. Heart rate (HR), mean arterial pressure (MAP), respiration rate (RR), lactate concentration (LC), and peripheral perfusion (PP) measured in rats were used as input variables for the RF model and its performance was compared with that of a logistic regression (LR) model. Before constructing the models, we performed 5-fold cross validation for RF variable selection, and forward stepwise variable selection for the LR model to examine which variables were important for the models. For the LR model, sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (ROC-AUC) were 0.83, 0.95, 0.88, and 0.96, respectively. For the RF models, sensitivity, specificity, accuracy, and AUC were 0.97, 0.95, 0.96, and 0.99, respectively. In conclusion, the RF model was superior to the LR model for survival prediction in the rat model.

• Journal of The Korean Society of Clinical Toxicology
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• v.10 no.2
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• pp.91-96
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• 2012

Purpose: A retrospective study with a literature review was conducted to identify the clinical characteristics and prognosis after the acute ingestion of glacial acetic acid. Methods: The medical records of 20 patients,who had presented to the emergency department of Ajou University Hospital complaining of the acute ingestion of glacial acetic acid between January 2006 and December 2011, were examined retrospectively. Results: Among the 172 patients admitted for caustics injury, 20 patients ingested glacial acetic acid. The mean age of the patients was $55{\pm}23.5$, and the mean volume of the acid was $84.5{\pm}71.3$ ml. The clinical features included 1) oral ulcers in 12 patients (63.2%), 2) respiratory difficulties in 11 patients (57.9%), 3) oliguria in 8 patients (42.1%), 4) renal toxicity in 7 patients (36.8%), 5) hepatic failure in 7 patients (36.8%), 6) disseminated intravascular boagulopathyin 7 patients (36.8%), 7) low blood pressure in 8 patients (42.1%), and 8) mental changes in 9 patients (47.4%). Ten patients required endotracheal intubation. Nine patients were admitted to the intensive care unit, and 5 patients expired. Conclusion: The ingestion of glacial acetic acid can cause severe symptoms, such as metabolic acidosis, multiple organ failure and upper airway swelling frequently and has a high mortality rate. Therefore, aggressive treatment, including endotracheal intubation, should be considered at the early stages.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1076-1080
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• 1996

The results about the myocardial protection of recta of the nitric oxide precursor L-arginine upon reperrusion injury after ischemia are diverse. These diversities may be model dependent. Experiments were designed and performed to investigate myocardial protection effects according to the concentration of L-arginine. The Isolated rat hearts were subjected in a 30 minutes oi normothermic ischemia and reperfused for 30 minutes with reperfusate containing 0, 1, 2, 3, 4 moil L-arginine. After 30 minutes of reperfusion, group with 1 and 2 mM/L L-arginine showed a trend of better recovery in left ventricular systolic function(left ventricular developed pressure, positive maximum dpfdt), diastolic function(negative maximum dpfdt) and coronary flow compared to control group(reperfusate no L-arginine). Recovery was impaired with a higher concentration, and at 4 moil L-arginine r covery was worse than control(p (0, 05). These results suggest that optimal concentration of L-arginine Is Important or the recovery of myocardial and endothelial function after ischemia and reperfusion.

• Tuberculosis and Respiratory Diseases
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• v.65 no.3
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• pp.222-224
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• 2008

Spontaneous pneumomediastinum is defined as a clinical syndrome that's characterized by the presence of air in the mediastinal space, which is not due to an old previous injury or surgery. The condition is caused by a sustained increase in the intraalveolar and intrabronchial pressure with extravasated air dissecting along the perivascular spaces of the mediastinum. This is an uncommon complication of sports activity. The most common symptom is chest pain. This diagnosis should be considered for younger people who present with pleuritic chest pain or dyspnea and a characteristic crackling feel (known as subcutaneous crepitation) when touching of the skin covering the chest wall or neck, and they look otherwise well with normal vital signs. Usually no treatment is required, but the mediastinal air will be absorbed faster if the patient inspires high concentrations of oxygen. We present here a case of spontaneous pneumomediastinum that occurred during a Taekwondo match, along with a review of the relevant literature.

• Archives of design research
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• v.19 no.6 s.68
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• pp.5-8
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• 2006

Inversion therapy has been used to relieve backpain, decrease pressure on the discs between vertebrae and stretch musdes as early as 400 BC. Gravity Guidance Inversion Table was introduced in 1960's and has been commercialized mostly for relieving backpain. in United States. But this machine needs to adjusted and possible sudden movement can cause severe injury to the users. In the 1990's, motor assisted inversion cram was introduced in Germany. But this inversion cram is too heavy and inconvenient to be used at home. In these days, the inversion machine become popular equipment in fitness clubs and health care places for relieving backpain as well as stretching muscles. And there is a growing need for home use version of motorized inversion machine. In this study, the motorized inversion machine was developed to be used for stretching exercise at home. The design became compact, simple and foldable as the results of adapting the wabble mechanism. And the machines are optimally designed by analyzing the torques applied to the machine by diverse physical size of users.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.80-83
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• 2009

Purpose: Isolated hypoglossal nerve palsy is a rare manifestation of various underlying disease. This article presents a rare complication of general anesthesia associated with an surgical procedure on a case of zygomatic fracture. Methods: An 18-year-old female patient was referred to our department by painful swelling on her left zygomatic area after the traffic accident. Left zygomatic complex fracture was identified on the simple x-ray and facial bone CT scan, and the fracture was treated with open reduction and internal fixation under general anesthesia. On the first postoperative day, she complained of difficulty in swallowing solid food, dysarthria and deviated tongue to her right side. There was no abnormal findings on the neurological examination, brain MRI and routine chemistry. She was diagnosed with transient hypoglossal nerve palsy and dexamethasone with multi-vitamins was administrated intravenously for 5 days. Results: The symptoms were completely resolved by the ninth postoperative day and the patient was discharged without any other complications. Conclusion: The hypoglossal(cranial nerve XII)nerve supplies motor innervation to all of the ipsilateral extrinsic and intrinsic tongue muscles. The hypoglossal nerve damage may caused by the compression between the airway and the hyoid bone during the endotracheal intubation, and direct trauma due to excessive pressure or neck extension. We described a rare case of unintended injury to hypoglossal nerve and care must be taken not to cause the hypoglossal nerve damage especially in facial plastic surgery with excessive neck extension under general anesthesia.

• Journal of Trauma and Injury
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• v.22 no.2
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• pp.167-171
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• 2009

Purpose: It is important to begin a transfusion safely and appropriately as soon as possible in a hemorrhagic shock patient. A group $O^+$ unmatched pack red blood cell (universal $O^+$) transfusion may satisfy that requirement. We report our experiences with universal $O^+$ to compare its usefulness for hemorrhagic shock patients with that of a matched pack red blood cell transfusion in the emergency department (ED). Methods: This is a retrospective study. Patients who had systolic blood pressure of less than 90 mmHg or a pulse rate of more than 120 beats per minute in the ED were included, and their medical records were reviewed. The collected data were demographic data, vital signs, blood test results, time to transfusion, the amount of transfusion, complications, and diagnoses. We calculated the emergency transfusion score (ETS) based on the patients' medical records. Results: Two hundred thirty-five patients were included. Forty-eight patients (36 trauma and 12 non-trauma patients) were transfused with a universal $O^+$. These patients had less time to transfusion compared with the cross-matched transfusion groups (35${\pm}$42 versus $170{\pm}187$ minutes, p<0.001). There were no differences in complications between groups (p=0.076). Of the patients who were transfused with universal $O^+$, 94.4% got more than 3 ETS. Conclusion: The universal $O^+$ transfusion, compared with matched pack red blood cell transfusion, should be a useful treatment for ED hemorrhagic shock patient due to its having a shorter time to transfusion without an increase in complications.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.4
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• pp.301-308
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• 2012

Objectives: To evaluate the pulmonary toxicity of 2 Korea asbestos(chrysotile, anthophyllite), Sprague-Dawely rats were exposed to 2 mg domestic asbestos by intratracheal instillation(IT). Methods: Lung function of rats was analyzed by pressure transducer(MAX1320, Buxco Electronics, USA). The effects of 2 mg asbestos(chrysotile ; $8,814,244{\times}10^{6}$ fibers/mg, average diameter 0.08 ${\mu}m$, average length 4.39 ${\mu}m$, anthophyllite ; $5,182{\times}10^{6}$ fibers/mg, average diameter 0.95 ${\mu}m$, average length 7.29 ${\mu}m$) on pulmonary function and pathological changes were evaluated at after a single IT. Lung function and histopathological evaluation were assessed in 5 animals from each group at each time point. Results: Due to differences in fiber numbers, chrysotile induce marked lung pathology and lung function change than anthophyllite at the same mass dose. Chrysotile showed notable thickening of interstitial areas surrounding the alveolar ducts and terminal bronchioles. Conclusions: On a mass dose basis, chrysotile that have 1,700 times numbers of fibers per unit weight than anthophyllite produced a greater persistent lung injury than anthophllite for at least 4 weeks after exposure.

• Archives of Plastic Surgery
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• v.33 no.1
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• pp.120-123
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• 2006

Spontaneous extensor pollicis longus tendon rupture is commonly caused by attrition of the tendon from trauma or inflammatory processes. We experienced a patient with extensor pollicis longus tendon rupture after steroid injection, in which the rupture may have been caused by the effects of steroid itself as well as direct damage from the needle. A 51-year-old woman complained of inability to extend her right thumb at the first metacarpophalangal & interphalangeal joint level. The patient had a history of local steroid injection into the dorsal & radial side of wrist on two occations, and had no history of trauma or rheumatologic disease. After a physical examination of the patient, we decided to explore the wrist. The patient agreed with operation. Intraoperatively, an incision was made into the wrist and the proximal and distal ends of the ruptured extensor pollicis longus tendon were identified. The defect between the proximal and the distal end was measured to approach 8cm, and a palmaris longus tendon graft was performed. After three months of rehabilitation, the first metacarpophalangal & interphalangeal joint recovered the normal range of motion. Steroid injection has been widely used in various musculoskeletal disorders such as rheumatoid arthritis and osteoarthritis. However, inadvertent steroid injection into the extra or intra articular spaces may lead to tendon rupture. Steroids reduce tensile strength by decreasing tenocyte activity and collagen synthesis. Also, the physical effect of direct needle-stick injury into the mesotenon and blood vessels around the tendon may cause damage. In addition, hematoma and edema may increase pressure around the tendon and compromise blood supply, leading to tendon degeneration and subsequent rupture. When injecting steroid into an articular area, all physicians should have a complete understanding of the surrounding anatomy and always keep in mind the hazards of such procedures.

• Fire Science and Engineering
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• v.26 no.3
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• pp.91-99
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• 2012

Fatal injuries and deaths have occurred resulting from the operation or disassembling of a powder extinguishers in Korea. If a rusted powder extinguisher is exploded during operation or disassembling, it rises to the air like a rocket and hits a head, chest, or neck part of an operator, resulting in his (her) death or injury. In this study examines the explosion accident cases of a powder fire extinguisher and analyzes their causes, reactions to explosion, and precautionary measures. And in this paper suggests 1) no using of old fire extinguishers in fire drill or education, 2) education and public information on danger of old fire extinguishers, 3) indication of explosion danger to cartridge-type dry chemical powder fire extinguishers had already placed to buildings etc., 4) obligatory indication of durable years on fire extinguishers, 5) examination for introduction of system that do hydraulic pressure test about fire extinguishers that given period past, 6) construction of system that reclaim old fire extinguishers, 7) construction of system that recycle or reuse old fire extinguishers, and 8) operation of help desk related to old fire extinguishers as precautionary measure of fire extinguisher explosion accidents.