Retinal prosthesis is regarded as the most feasible method for the blind caused by retinal diseases such as retinitis pigmentosa or age-related macular degeneration. One of the prerequisites for the success of retinal prosthesis is the optimization of the electrical stimuli applied through the prosthesis. Since electrical characteristics of degenerate retina are expected to differ from those of normal retina, we investigated differences of the retinal waveforms in normal and degenerate retina to provide a guideline for the optimization of electrical stimulation for the upcoming prosthesis. After isolation of retina, retinal patch was attached with the ganglion cell side facing the surface of microelectrode arrays (MEA). 8x8 grid layout MEA (electrode diameter: 30micrometer, electrode spacing: 200micrometer, and impedance: 50 k omega at 1 kHz) was used to record in-vitro retinal ganglion cell activity. In normal mice (C57BL/6J strain) of postnatal day 28, only short duration (<2 ms) retinal spikes were recorded. In rd/rd mice (C3H/HeJ strain), besides normal spikes, waveform with longer duration (~100 ms), the slow wave component was recorded. We attempted to understand the mechanism of this slow wave component in degenerate retina using various synaptic blockers. We suggest that stronger glutamatergic input from bipolar cell to the ganglion cell in rd/rd mouse than normal mouse contributes the most to this slow wave component. Out of many degenerative changes, we favor elimination of the inhibitory horizontal input to bipolar cells as a main contributor for a relatively stronger input from bipolar cell to ganglion cell in rd/rd mouse.
Animals ; Electric Stimulation ; Electrodes ; Ganglion Cysts ; Macular Degeneration ; Mice ; Microelectrodes ; Prostheses and Implants ; Retina ; Retinal Diseases ; Retinal Ganglion Cells ; Retinaldehyde ; Retinitis Pigmentosa ; Visual Prosthesis

Cardiovascular disease is the most important cause of unexpected sudden death. Although ischemic heart disease by coronary atherosclerosis is the most common cause of sudden cardiac death, other diseases such as cardiomyopathy, congenital heart disease, valvular heart disease and rarely myocarditis can produce sudden cardiac death. Myocarditis is an inflammatory process of the myocardium characterized by an interstitial inflammatory infiltrate and an injury to myocytes adjacent to the inflammatory cells. The clinical expression of myocarditis ranges from the asymptomatic state to fulminant fatal congestive heart failure. Because myocardial involvement is subclinical in most acute infectious disease, the majority of patients have no specific complaints referable to the cardiovascular system. It is possible that it causes a medicolegal problems in case of sudden death. Therefore, author reviewed the clinical and pathological findings of 18 myocarditis autopsy cases. The victims 'age was varied 4-month-59-year olds. 5 (28%) were male and 13 (72%) were female. 15 cases received medical treatment due to clinical symptoms(URI symptoms: 2 cases, tonsillitis and tonsillar abcess: 3 cases, GI symptoms: 5 cases, URI & GI symptoms: 3 cases, pneumonia: 1 case, operation due to ovarian tumor: 1 case) and were associated with medicolegal problem. By the results of this study, important gross findings were pericardial effusions, characteristic cardiomegaly, and pulmonary edema.
Asymptomatic Diseases ; Autopsy ; Cardiomegaly ; Cardiomyopathies ; Cardiovascular Diseases ; Cardiovascular System ; Communicable Diseases ; Coronary Artery Disease ; Death, Sudden ; Death, Sudden, Cardiac ; Female ; Heart Defects, Congenital ; Heart Failure ; Heart Valve Diseases ; Humans ; Male ; Muscle Cells ; Myocardial Ischemia ; Myocarditis* ; Myocardium ; Palatine Tonsil ; Pericardial Effusion ; Pneumonia ; Pulmonary Edema ; Tonsillitis

OBJECTIVE: To compare the scar formation and hand function between moist exposed burn ointment (MEBO) treatment and conventional skin graft in full thickness hand burns. METHOD: Prospective comparative study was done between MEBO treatment group and conventional skin graft group. Full thickness burn wound scars on dorsal hand were compared. Scars were assessed with the Vancouver scar scale and other objective measurement tools such as pigmentation, erythema, pliability, transepideramal water loss, thickness and perfusion. Hand function was evaluated by the Jebsen hand function test and Michigan Hand Function Questionnaire. RESULTS: Vancouver Scar scale showed significantly better scores in the MEBO group than in the conventional skin graft group. Scar thickness and transepidermal water loss were greater in the MEBO treatment group whereas pigmentation value was greater in the conventional skin graft group. There was no significant difference in the hand function between the two groups. CONCLUSION: MEBO application could be an alternative treatment to conventional skin graft treatment in full thickness hand burn wounds. In the future, more studies are yet to come how MEBO treatment may affect the skin condition of the burn injuries.
Burns* ; Cicatrix* ; Erythema ; Hand* ; Michigan ; Perfusion ; Pigmentation ; Pliability ; Prospective Studies ; Surveys and Questionnaires ; Skin* ; Transplants* ; Wounds and Injuries

Although the management of fractures of the calcaneus still remains controversial, open reduction and internal fixation is gaining in popularity as the method of choice for the treatment of displaced intraarticular calcaneal fractures. However, open methods can make several complications such as neurovascular injury and infection. Thus we have performed the new technique of arthroscopic reduction and minimal internal fixation for displaced intraarticular calcaneal fractures in 5 cases. The results were evaluated between 12 and 16 months after surgery. A Bohler angle was restored to 25degrees-40degrees in all cases. Anatomical reduction of articular surface were obtained from 4 cases out of 5. No complications were found except 1 peroneal tendinitis. The clinical results by Creighton-Nebraska health foundation assessment for fractures of the calcaneus were 3 excellent, 1 good and 1 fair. Even though this was a few case and a short term follow-up study, the arthroscopic assisted management of displaced intraarticular calcaneal fracture induced a little complications and satisfactory results.
Calcaneus ; Follow-Up Studies ; Tendinopathy

Objectives: . To determine the appropriate anatomical borders of implantation on the temporal bone in a cadaver study, and to develop a simplified surgical technique for Baha Attract implantation through a small incision along the hairline using anatomical evidence and a navigation system. Methods: . In a cadaver study, 20 human adult dry skulls were used to find flat areas of the temporal bone for Baha Attract magnet implantation. Four borders of the “optimal surgical site” were defined: Asterion line, occipitomastoid suture line, sigmoid sinus line, and digastric groove line. In three patients, we implanted the Baha Attract according to the newly developed surgical procedure and validated the feasibility of this technique with a navigation system. Results: . We identified the appropriate position of the implant on the temporal bone, suggesting a simplified surgical technique for Baha Attract with a small incision. We determined the spot of implantation, and the implants were inserted through a small surgical incision (<2.5 cm) under local anesthesia; the procedure lasted approximately 30 minutes. Conclusion . The optimal surgical site of the temporal bone is a safe and easily accessible location for implantation of the Baha Attract.

STUDY DESIGN: Retrospective study. PURPOSE: To estimate the usefulness of bone scan and magnetic resonance imaging (MRI) for the diagnosis of new fracture in osteoporotic vertebral fractures. OVERVIEW OF LITERATURE: The diagnosis of new fractrure in osteoporotic vertebral fractures requires simple X-ray and supplementary studies. METHODS: We analyzed 87 vertebrae in 44 patients, who diagnosed with osteoporotic vertebral fractures using bone scan and MRI within 2 months interval between August 2001 and July 2008. We compared hot uptakes in bone scan with MRI findings such as new fractures, old fractures and degenerative lesions. RESULTS: Hot uptakes in bone scan was matched to 48 new fractures, 26 old fractures and 13 degenerative lesions in MRI findings. It was 55% of concordance between hot uptakes in bone scan and new fractures in MRI. The rate of new vertebral fractures confirmed by MRI according to 1 level hot uptakes in bone scan was 96%, 2 levels was 50% and 3 more levels was 36%. CONCLUSIONS: The diagnosis of new fracture in osteoporotic vertebral fractures requires simple X-ray and supplementary studies such as bone scan and MRI. We recommend more careful interpretation in multiple osteoporotic vertebral fracture patients about hot uptake lesions of bone scan.
Fractures, Compression ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Spine

Flowable resins can be used as a base material during the restoration of deep tooth cavity. The purpose of the present study was to evaluate the mechanical properties of the layered specimens which have flowable resin as a base material. For the study, two composite resins and five flowable resins were chosen for the overlying and base materials, respectively. Flexural and compressive properties of each bulk and ten layered specimens were measured. Layered specimens showed high flexural strength (FS) and flexural modulus (FM) if bulk state FS and FM of the base flowable resin are high. However, compressive strength (CS) was not that case. CS of the layered specimen was not high (251.4~295.3 MPa) whether CS of the bulk state is high or not (259.8~439.8 MPa). FM showed high linear correlation with CM. After all mechanical properties of the layered specimens were not consistently influenced by the mechanical properties of the base flowable resins regardless of the overlying composite resins.
Composite Resins ; Compressive Strength ; Tooth

Two autopsy cases of asphyxia due to oxygen deficiency are reported. The first case is that a 38-year-old man died in a storehouse. Many pears were stored in a storehouse and the its atmosphere was strictly controlled. The second case is that a 42-year-old man died in the boiler room of a fishing ship. Much amount of Freon gas escaped due to a defect of the refrigerator in the boiler room. The victim entered the boiler room because he repaired the refrigerator. But, the victim died when he entered the boiler room immediately. In this article, the autopsy findings and the contents of the investigation of scene of two cases are described.
Adult ; Anoxia* ; Asphyxia* ; Atmosphere ; Autopsy* ; Chlorofluorocarbons ; Humans ; Oxygen* ; Pyrus ; Ships ; United Nations

Postmortem body inspection at scene and examination of the scene of death are very important in determination of the suspected cause of death, manner of death and interpretation of events leading death, nature of injuries, time of death etc. Actually these works must be performed by well-experienced forensic pathologists. And forensic pathologists should visit the scene of death before the body is removed. In Korea, attendance at scene of death by forensic pathologists is not performed effectively due to low faculty of forensic pathologists and the problem of medicolegal investigation system. But we try to overcome these problems and begin to the work of postmortem body inspection at scene and examination of the scene of body in area of Daejeon Metropolitan city since March, 2003. In this report we recommend the guideline for postmortem body inspection at scene on forensic aspects. We believe that sharing the experience and knowledge about scene investigation including postmortem body inspection at scene and examination of the scene of death is very important to improve and change the environment of medicolegal investigation system in the future.
Cause of Death ; Korea

BACKGROUND: Becker's nevus is a relatively common pigmented smooth muscle harmatoma that develops during adolescence and occurs primarily in young men. The nevus, characterized by hypertrichosis and hyperpigmentation, is usually located unilaterally over the shoulder, upper arm, and scapula. These nevi are not only cosmetically undesirable but also psychologically distressing, as traditional surgical therapies have been either unsuccessful or have resulted in scarring. OBJECTIVE: We evaluated the clinical improvement of 14 patients with a becker's nevus who were treated with a Q-switched (QS) frequency doubled ND: YAG laser in order to decrease pigmentation. METHODS: Our study was designed by analyzing the clinical improvement of outpatients with becker's nevus via clinical examination and photography. RESULTS: The results were as follows; Male to female ratio of 2.5: 1. The mean age was 19.7 years old and the subjects in most of the studies were young adult. The mean age of onset was 5.7 years old (below 5 years old: n=8, 57%). We treated 14 patients with a QS ND: YAG laser. The patients' response to treatment was; excellent; 14%, good; 36%, fair; 21%, and poor; 29%. Conparison, was made, of the positive clinical improvement in patients who received treatment once (n=10) and those who received treatment more than twice (n=4). Multiple treatments (75%) showed superior improvement compared with single treatment (40%). The clinical improvement, the according to the area of lesions, was the best in the neck (100%) and the worst in the trunk (25%). The lesions were accompanied by hair in 6 cases. Among these, the excellent or good cases were 33%. The other patients (8 cases) without hairs had more positive results (63%). Treatment effects according to laser fluence were not shown to be significant. During the study, the most common complication was hyperpigmentation (36%), followed by transient erythema (14%). Scarring or hypopigmenatation had resulted in none. CONCLUSION: Our data suggested that QS ND: YAG laser irradiation is an effective and safe method to treat the hyperpigmentation characteristic of a becker's nevus. Long-term further evaluation will be necessary to determine whether the favorable results observed in these patient will be permanent.
Adolescent ; Age of Onset ; Arm ; Child, Preschool ; Cicatrix ; Erythema ; Female ; Hair ; Humans ; Hyperpigmentation ; Hypertrichosis ; Lasers, Solid-State* ; Male ; Muscle, Smooth ; Neck ; Nevus* ; Outpatients ; Photography ; Pigmentation ; Scapula ; Shoulder ; Young Adult