• 한국전기전자재료학회논문지
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• 제22권8호
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• pp.704-713
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• 2009

As using recruitment phenomenon, SISI test and Bekesy audiometry are employed to differentially diagnose both the cochlear hearing loss and the retrocochlear hearing loss. The main purpose of this study is to find out the sensitivity and specificity of the SISI test within the scope of 1 KHz to 4 KHz in diagnosing various types of hearing losses. In this study, the Bekesy audiometry was conducted for Bekesy audiograms of certain groups according to Jerger's classification, which included persons with normal hearing and patients with hearing impairment. Subject persons of the SISI test were categorized into the several groups with normal hearing, mild hearing loss, moderate hearing loss, moderate-severe hearing loss and severe hearing loss, respectively. The sensitivity and specificity of certain groups were evaluated according to the SISI scores of 20 % below, 25 ${\sim}$ 65 %, and more than 70%. Also, the Bekesy audiometry is conducted on the several subject groups with normal hearing, mixed hearing loss, and sensori-neural hearing loss.

• 한국산학기술학회논문지
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• 제11권4호
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• pp.1325-1332
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• 2010

미세증가감수지수 검사는 감각신경성난청의 세부 병변을 감별하기 위하여 사용되는 누가현상을 판별하는 검사이다. 본 논문은 PC 기반 소프트웨어로 구현한 미세증가감수지수 검사 소프트웨어를 기술한다. 구현된 소프트웨어는 검사자의 검사 참여 유 무에 따라 수동 검사와 자동 검사의 두 가지 모드를 제공함으로써 경제적인 검사가 진행 될 수 있게 한다. 또 필요할 경우에 자동으로 차폐를 수행한다. 그리고 1dB의 순간 상승음에 대한 검사뿐만 아니라 2dB와 5dB 상승음에 대한 검사도 지원함으로써 보다 정확한 검사 결과를 얻을 수 있도록 한다.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1981년도 제15차 학술대회연제순서 및 초록
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• pp.40.3-41
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• 1981

난청을 동반하는 어린선상 피부질환은 상염색체성 열성으로 유전되는 질환으로 피부에 인설이 과다하게 축적되는 것이 특징이며 피부병변이외에도 다른 선천성 기형이 동반되는 증후군을 형성하는 경우가 많다. 최근 선천성 어린선상 피부병, 난청 및 각막염이 동반된 몇몇 증례들이 보고되었으며 이들은 하나의 증후군으로 생각되고 있다. 저자들은 선천성 어린선상 피부병과 감각신경성 난청, 각막염, 탈모증, 조갑 및 치아의 이상등이 있는26세 여자환자에서 청력검사를 시행하여 다음과 같은 소견을 얻었다. 순음청력역치는 양측에 고도의 감각신경성 난청을 보이며 SISI검사는 1,000Hz, 4,000Hz 양측 모두 100%, Tone decay 검사는 1,000Hz, 4,000Hz에서 양측 모두 25dB의 decay를 보였으며 어음청역검사상 어음청취역치가 좌우측 모두 85dB이었고 MCL(Most Comfortable level)인 95dB에서 양측 모두 80%의 명료도를 보였다. 이상의 결과는 이 질환에 의한 청력손실이 와우병변에 기인하는 것으로 생각할 수 있었다.

• Nutrition Research and Practice
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• 제18권4호
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• pp.479-497
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• 2024

BACKGROUND/OBJECTIVES: Activating brown adipose tissue (BAT) and browning of white adipose tissue (WAT) can protect against obesity and obesity-related metabolic conditions. Cryptotanshinone (CT) regulates lipid metabolism and significantly ameliorates insulin resistance. Adenosine-5'-monophosphate (AMP)-activated protein kinase (AMPK), a receptor for cellular energy metabolism, is believed to regulate brown fat activity in humans. MATERIALS/METHODS: The in vivo study included high-fat-fed obese mice administered orally 200/400 mg/kg/d CT. They were evaluated through weight measurement, the intraperitoneal glucose tolerance test (IPGTT), intraperitoneal insulin tolerance test (IPITT), cold stimulation test, serum lipid (total cholesterol, triglycerides, and low-density lipoprotein) measurement, hematoxylin and eosin staining, and immunohistochemistry. Furthermore, the in vitro study investigated primary adipose mesenchymal stem cells (MSCs) with incubation of CT and AMPK agonists (acadesine)/inhibitor (Compound C). Cells were evaluated using Oil Red O staining, Alizarin red staining, flow cytometry, and immunofluorescence staining to identify and observe the osteogenic versus adipogenic differentiation. Quantitative real-time polymerase chain reaction and the Western blot were used to observe related gene expression. RESULTS: In the diet-induced obesity mouse model mice CT suppressed body weight, food intake, glucose levels in the IPGTT and IPTT, serum lipids, the volume of adipose tissue, and increased thermogenesis, uncoupling protein 1, and the AMPK pathway expression. In the in vitro study, CT prevented the formation of lipid droplets from MSCs while activating brown genes and the AMPK pathway. AMPK activator enhanced CT's effects, while the AMPK inhibitor reversed the effects of CT. CONCLUSION: CT promotes adipose tissue browning to increase body thermogenesis and reduce obesity by activating the AMPK pathway. This study provides an experimental foundation for the use of CT in obesity treatment.

• Journal of Ginseng Research
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• 제44권5호
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• pp.717-724
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• 2020

Background: Malignant arrhythmias require drug therapy. However, most of the currently available antiarrhythmic drugs have significant side effects. Ginsenoside Rg2 exhibits excellent cardioprotective effects and appears to be a promising candidate for cardiovascular drug development. So far, the oral toxicity and antiarrhythmic effects of Rg2 have not been evaluated. Methods: Acute oral toxicity of Rg2 was assessed by the Limit Test method in mice. Subchronic oral toxicity was determined by repeated dose 28-day toxicity study in rats. Antiarrhythmic activities of Rg2 were evaluated in calcium chloride-induced arrhythmic rats. Antiarrhythmic mechanism of Rg2 was investigated in arrhythmic rats and H9c2 cardiomyocytes. Results: The results of toxicity studies indicated that Rg2 exhibited no single-dose (10 g/kg) acute oral toxicity. And 28-day repeated dose treatment with Rg2 (1.75, 3.5 and 5 g/kg/d) demonstrated minimal, if any, subchronic toxicity. Serum biochemical examination showed that total cholesterol in the high-dose cohort was dramatically decreased, whereas prothrombin time was increased at Day 28, suggesting that Rg2 might regulate lipid metabolism and have a potential anticoagulant effect. Moreover, pretreatment with Rg2 showed antiarrhythmic effects on the rat model of calcium chloride induced arrhythmia, in terms of the reduced duration time, mortality, and incidence of malignant arrhythmias. The antiarrhythmic mechanism of Rg2 might be the inhibition of calcium influx through L-type calcium channels by suppressing the phosphorylation of Ca²⁺/calmodulin-dependent protein kinase II. Conclusion: Our findings support the development of Rg2 as a promising antiarrhythmic drug with fewer side effects for clinical use.

• Transactions on Electrical and Electronic Materials
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• 제13권3호
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• pp.116-120
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• 2012

In this paper, ZnO-Epoxy nanocomposites (NEP) were prepared and epoxy composites that contain 5 wt% micro ZnO (MEP) and deliberately not well dispersed nano ZnO (NDNEP) were also prepared for purpose of comparison. The effects of the particle size and dispersion of ZnO on dielectric properties of epoxy resin were chiefly studied. Test results showed that: at a loading of 5 wt%, the three epoxy composites seem to have no significant difference on resistivity compared to epoxy resin; Dielectric constants of all the epoxy composites are also basically the same but they are bigger compared to that of the pure epoxy resin (unfilled); Dielectric dissipation factors ($tan{\delta}$) of NDNEP is greater than that of NEP and MEP. NEP has the minimum dielectric loss factor, whereas dielectric loss factors of the three epoxy composites are larger than that of the pure epoxy resin. The decreasing order of electrical breakdown strength for the three epoxy composites and for the pure epoxy resin is as follows: NEP>MEP>NDNEP>EP. Finally, in order to explain the experimental results the aggregation interface phase was proposed. Furthermore, addition of well dispersed nano filler has proved to have a positive effect on the improvement of the dielectric properties of epoxy resin.