• BMB Reports
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• 제52권1호
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• pp.24-34
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• 2019

Sirtuin is an essential factor that delays cellular senescence and extends the organismal lifespan through the regulation of diverse cellular processes. Suppression of cellular senescence by Sirtuin is mainly mediated through delaying the age-related telomere attrition, sustaining genome integrity and promotion of DNA damage repair. In addition, Sirtuin modulates the organismal lifespan by interacting with several lifespan regulating signaling pathways including insulin/IGF-1 signaling pathway, AMP-activated protein kinase, and forkhead box O. Although still controversial, it is suggested that the prolongevity effect of Sirtuin is dependent with the level of and with the tissue expression of Sirtuin. Since Sirtuin is also believed to mediate the prolongevity effect of calorie restriction, activators of Sirtuin have attracted the attention of researchers to develop therapeutics for age-related diseases. Resveratrol, a phytochemical rich in the skin of red grapes and wine, has been actively investigated to activate Sirtuin activity with consequent beneficial effects on aging. This article reviews the evidences and controversies regarding the roles of Sirtuin on cellular senescence and lifespan extension, and summarizes the activators of Sirtuin including Sirtuin-activating compounds and compounds that increase the cellular level of nicotinamide dinucleotide.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.172-173
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• 2019

As the damage to fine dust increased, the Republic of Korea designated fine dust as a social disaster. The composition of the fine dust is composed of carbon, sulfate, nitrate, ammonium and minerals. The cause of fine dust is naturally generated by dirt, pollen, etc. In addition, there are artificial causes such as gaseous vehicle exhaust gas emitted from the use of fossil fuel. When fine dust enters the human body through breathing, it causes various respiratory diseases and skin diseases. In IARC, fine dust was designated as a carcinogen group 1. In this research, we tried to adsorb fine dust by physical adsorption using powdered activate carbon. Powdered activate carbon is a powdered activated carbon activated in a carbonized state. Porous material with high specific surface area and low density. Experimental items were tested for density, water absorption, and fine dust concentration according to the PAC addition ratio. Basic experiments were carried out to fabricate the fine dust adsorption matrix.

• 대한두개안면성형외과학회지
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• 제22권1호
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• pp.52-55
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• 2021

Complete surgical excision within a margin of normal healthy bone is the treatment of choice for intraosseous hemangioma. A 56-year-old man visited with complaints of a firm, mildly tender, immovable, and palpable mass on the right forehead (size: 1.5×1.5 cm). Non-contrast brain computed tomography performed preoperatively revealed a 1.5 cm heterogenous osteolytic lesion with suspected internal trabeculation in the right frontal bone. Under general anesthesia, a 2 cm transverse incision was made on the forehead skin rather than bicoronal incision. Full-thickness en bloc resection of the frontal bone including the mass was performed. The frontal bone was removed with care taken not to damage the frontal sinus mucosa. The frontal sinus was sealed with a collagen patch (Tachocomb) and a cranioplasty was performed using bone cement. At 6 months postoperative, a clean wound was confirmed without any complications, and there was no local recurrence. Surgical excision of intraosseous hemangioma in the frontal sinus bone can be performed via direct incision or the bicoronal approach. In this case, the direct incision approach was used to achieve smaller scars and faster recovery than the bicoronal approach.

• Journal of Audiology & Otology
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• 제23권4호
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• pp.204-209
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• 2019

For a minimally invasive approach to access the facial nerve, we designed an extended epitympanotomy via a transmastoid approach that has proven useful in cases of traumatic facial nerve palsy and pre-cholesteatoma. To evaluate the surgical exposure through an extended epitympanotomy, six patients with traumatic facial nerve palsy were enrolled in this study. The same surgical technique was used in all patients. Patients were assessed and the degree of facial nerve paralysis was determined prior to surgery, 1-week post-operatively, and 6-months post-operatively using the House-Brackmann grading system. In all cases, surgical exposure was adequate. All patients with traumatic facial nerve palsy were male and the age range was 13 to 83 years. In all cases, the location of the facial nerve damage was limited to the area between the first and second genu. Symptoms of all the patients improved by 6 months post-operation (p=0.024). There were no complications in any of the patients. Extended epitympanotomy is useful for safe, rapid surgical exposure of the attic area, sparing the patient post-operative dimpling, skin incision complications, and lengthy exposure to anesthesia. We suggest that surgery for patients with facial nerve palsy secondary to trauma be performed using this described technique.

• Composites Research
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• 제22권3호
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• pp.55-59
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• 2009

마이크로스트림 안테나는 가볍고 부피가 작을 뿐만 아니라 집적화가 가능하고, 표면 부착력이 탁월하여 많은 통신 시스템 안테나로 응용되고 있다. 안테나의 구조는 12.5GHz의 중심주파수를 갖는 사각 패치 마이크로 스트립 안테나로 설계하였고 곡률 방향으로 패치를 확장시켜 총 4개의 패치를 배열시켰다. 양쪽의 복합재료 사이에 허니컴을 삽입한 샌드위치 구조물이 되도록 설계한 다음 충격 실험을 실시하였다. 충격실험 후 안테나 성능변화를 측정한 결과 영향을 받지 않는다는 것을 확인하였다.

• 대한청각학회지
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• 제23권4호
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• pp.204-209
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• 2019

For a minimally invasive approach to access the facial nerve, we designed an extended epitympanotomy via a transmastoid approach that has proven useful in cases of traumatic facial nerve palsy and pre-cholesteatoma. To evaluate the surgical exposure through an extended epitympanotomy, six patients with traumatic facial nerve palsy were enrolled in this study. The same surgical technique was used in all patients. Patients were assessed and the degree of facial nerve paralysis was determined prior to surgery, 1-week post-operatively, and 6-months post-operatively using the House-Brackmann grading system. In all cases, surgical exposure was adequate. All patients with traumatic facial nerve palsy were male and the age range was 13 to 83 years. In all cases, the location of the facial nerve damage was limited to the area between the first and second genu. Symptoms of all the patients improved by 6 months post-operation (p=0.024). There were no complications in any of the patients. Extended epitympanotomy is useful for safe, rapid surgical exposure of the attic area, sparing the patient post-operative dimpling, skin incision complications, and lengthy exposure to anesthesia. We suggest that surgery for patients with facial nerve palsy secondary to trauma be performed using this described technique.

• Journal of Yeungnam Medical Science
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• 제40권4호
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• pp.328-334
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• 2023

An aging population and changes in dietary habits have increased the incidence of diabetes, resulting in complications such as diabetic foot ulcers (DFUs). DFUs can lead to serious disabilities, substantial reductions in patient quality of life, and high financial costs for society. By understanding the etiology and pathophysiology of DFUs, their occurrence can be prevented and managed more effectively. The pathophysiology of DFUs involves metabolic dysfunction, diabetic immunopathy, diabetic neuropathy, and angiopathy. The processes by which hyperglycemia causes peripheral nerve damage are related to adenosine triphosphate deficiency, the polyol pathway, oxidative stress, protein kinase C activity, and proinflammatory processes. In the context of hyperglycemia, the suppression of endothelial nitric oxide production leads to microcirculation atherosclerosis, heightened inflammation, and abnormal intimal growth. Diabetic neuropathy involves sensory, motor, and autonomic neuropathies. The interaction between these neuropathies forms a callus that leads to subcutaneous hemorrhage and skin ulcers. Hyperglycemia causes peripheral vascular changes that result in endothelial cell dysfunction and decreased vasodilator secretion, leading to ischemia. The interplay among these four preceding pathophysiological factors fosters the development and progression of infections in individuals with diabetes. Charcot neuroarthropathy is a chronic and progressive degenerative arthropathy characterized by heightened blood flow, increased calcium dissolution, and repeated minor trauma to insensate joints. Directly and comprehensively addressing the pathogenesis of DFUs could pave the way for the development of innovative treatment approaches with the potential to avoid the most serious complications, including major amputations.

• 공업화학
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• 제24권5호
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• pp.483-488
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• 2013

본 연구에서는, 레스베라트롤의 산화적 손상대한 세포 보호 효과와 항산화능을 조사하였다. 레스베라트롤의 Free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) 소거활성은 ($FSC_{50}$) $103{\mu}M$로 나타났다. 루미놀화학발광법을 이용하여 $Fe^{3+}-EDTA/H_2O_2$계에서 레스베라트롤의 활성산소(Reactive oxygen species, ROS) 소거활성은($OSC_{50}$)을 평가하였다. 레스베라트롤은 $0.042{\mu}M$로 나타나 비교물질로 사용한 L-ascorbic acid ($0.405{\mu}M$)보다 9.6배 우수한 활성산소 소거활성을 보였다. 또한 레스베라트롤은 지용성 항산화제로 알려진 (+)-${\alpha}$-tocopherol보다 우수한 세포보호 활성을 나타내었다. 세포독성 조사에서 레스베라트롤은 $50{\mu}M$에서 세포독성을 나타내지 않았다. HaCaT 세포에 $800mJ/cm^2$의 UVB 또는 $30{\mu}M$의 rose-bengal을 처리하였을 때, 레스베라트롤은 농도의존적으로 세포의 산화적 손상에 대항하여 세포를 보호하였다. 그러나 10 mM의 $H_2O_2$를 처리한 경우에, 레스베라트롤은 세포보호 효과를 나타내지 않았다. 이들의 결과들은 레스베라트롤이 항산화능 및 세포보호 효과를 통해서 피부 노화를 예방하고 개선하는데 있어 이용 가능함을 시사한다.

• Archives of Plastic Surgery
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• 제41권4호
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• pp.317-324
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• 2014

Background Burn infliction techniques are poorly described in rat models. An accurate study can only be achieved with wounds that are uniform in size and depth. We describe a simple reproducible method for creating consistent burn wounds in rats. Methods Ten male Sprague-Dawley rats were anesthetized and dorsum shaved. A 100 g cylindrical stainless-steel rod (1 cm diameter) was heated to $100^{\circ}C$ in boiling water. Temperature was monitored using a thermocouple. We performed two consecutive toe-pinch tests on different limbs to assess the depth of sedation. Burn infliction was limited to the loin. The skin was pulled upwards, away from the underlying viscera, creating a flat surface. The rod rested on its own weight for 5, 10, and 20 seconds at three different sites on each rat. Wounds were evaluated for size, morphology and depth. Results Average wound size was $0.9957cm^2$ (standard deviation [SD] 0.1845) (n=30). Wounds created with duration of 5 seconds were pale, with an indistinct margin of erythema. Wounds of 10 and 20 seconds were well-defined, uniformly brown with a rim of erythema. Average depths of tissue damage were 1.30 mm (SD 0.424), 2.35 mm (SD 0.071), and 2.60 mm (SD 0.283) for duration of 5, 10, 20 seconds respectively. Burn duration of 5 seconds resulted in full-thickness damage. Burn duration of 10 seconds and 20 seconds resulted in full-thickness damage, involving subjacent skeletal muscle. Conclusions This is a simple reproducible method for creating burn wounds consistent in size and depth in a rat burn model.

• 한국식품과학회지
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• 제45권3호
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• pp.350-355
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• 2013

본 연구에서는 효모를 이용하여 제조한 미나리 천연 식초 및 원료로 사용된 미나리 발효액의 유리당, 유기산, 아미노산 함량을 측정하였으며, 미나리 식초의 뇌 기능 개선 관련 기능성을 확인하기 위하여 C6 흰쥐 신경아교세포를 이용하여 산화적 손상에 대한 보호 효과를 검토하였다. 미나리 식초는 약 5%의 초산을 함유하였으며 glucose는 검출되지 않아 초산발효가 잘 이루어진 것을 알 수 있다. 또한 유리 아미노산의 함량은 높지 않았으나 그 중 aspartic acid, arginine 그리고 valine이 주요 유리 아미노산으로 나타났으며, 발효액에서는 aspartic acid, alanine, GABA의 순으로 나타났다. 총 아미노산은 식초에서는 glutamic acid와 glutamine의 함량이 가장 높았으며, 발효액의 경우 aspartic acid와 asparagine이 주요 총 아미노산으로 나타났다. 미나리 식초의 효능을 평가하기 위하여 식초를 동결 건조하여 분말화한 식초의 산화적 손상에 대한 뇌 신경세포 보호 효과를 측정한 결과, 발효액과 식초 모두 C6 세포에 대한 독성은 없었으며 t-BHP 및 $H_2O_2$에 의한 세포 생존율 저하를 유의적으로 억제하는 효과를 확인하였다.