고주파 유도가열 원리를 이용한 기상반응기 가열효과 분선

이승범,홍인권,천지득 한국공업화학회 2002 공업화학 Vol.13 No.4

본 연구에서는 공정 배출가스로부터 대기오염물질, 특히 휘발성 유기화합물이나 다이옥신 등의 제거를 위한 예비실험으로서 고주파 유도가열 방식을 도입한 기상반응기 가열공정을 개발하였다. 기상 반응기에 공기를 통과시켜 공기의 가열효과를 분석하고, 실제 공정에서의 적용가능성을 평가하였다. 실험에 사용된 고주파 발생장치는 최대출력 7.5 kW, 발진주파수 20 kHz인 고주파 유도가열장치이며, 공기의 유입온도는 상온(20 ℃)과 200 ℃로 설정하였다. 공기의 가열온도는 고주파의 출력과 체류시간 증가에 따라 증가되었으며, 특히 체류시간 3 s 이하의 조건에서는 가열효과가 급격히 감소되었다. 또한 유해가스의 처리 시 요구되는 온도 700∼800 ℃에 도달하는 온도를 얻을 수 있었으며, 출력의 증가나 에너지 손실을 줄이는 공정을 응용한다면 그 이상의 온도를 얻을 것으로 사료된다. 또한 기존의 공정에 비해 빠른 가열이 가능하여 산업현장에서의 이용가능성이 높을 것으로 기대된다. The thermal oxidation of air pollution substance (VOCs and dioxin, etc.) was studied using a high frequency induction heating process. To identify the heating effects on the air phase, a plug flow type gas reactor was designed. The induction heating system had the capacity to generate maximum of 7.5 kW and 20 kHz, and the inlet gas temperature was maintained between 20 and 200 ℃. The air temperature was increased as the induction heating power and time constant were increased. However, the air temperature decreased rapidly for the time constant less than 3 seconds. The maximum heating temperature was in the range of 700 and 800 ℃. In comparison to a conventional heating process, the benefit of using a high frequency induction heating process was the reduced requirement of heating time.

Evaluation of the dermatophyte test strip for diagnostic tool to detect dermatophytes in tinea unguium

( Ji Youn Hong ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Byung Gon Choi ),( Song Hee Han ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: The direct microscopy and fungal culture are the gold standard to diagnose tinea unguium, however, the results tend to be dependent on performer’s skill. The Dermatophyte Test Strip, a novel diagnostic tool to detect dermatophytes, facilitates the diagnosis of tinea unguium. Objectives: We aimed to evaluate the capacity of the Dermatophyte Test Strip to detect dermatophytes in tinea unguium specimens in comparison with the direct microscopy. Methods: The direct microscopy and the Dermatophyte Test Strip were performed on the specimens to detect dermatophytes. If the results of the two tests were different, polymerase chain reaction (PCR) was used to confirm the presence of dermatophytes. Results: We analyzed 120 specimens clinically suspected tinea unguium. The 77 (64.2%) specimens showed positive results on the direct microscopy. In comparison, the 66 (55%) specimens showed positive results on the Dermatophyte Test Strip. In all of the 27 specimens on PCR, the dermatophytes were detected. When comparing the results of the direct microscopy combined with PCR and the results of Dermatophyte Test Strip, the positive/negative/overall concordance rate were 100%, 81.4%, 93.3% respectively and κ-coefficient was 0.85 (95% confidence interval, 0.75-0.95). Conclusion: This study suggests that the Dermatophyte Test Strip may be a useful diagnostic tool to detect dermatophytes in clinically suspected tinea unguium specimens.

A case of calcinosis cutis of the fingertip

( Ji Youn Hong ),( Ji Su Lee ),( Sung Min Kim ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.1

A 31-year-old male patient presented our clinic with a 3-month history of a yellowish globular-shaped subcutaneous firm nodule on right third fingertip. He complained of perilesional pain but had no systemic symptoms. He denied any history of trauma in the lesion, and medical past history. A biopsy was performed under clinical suspicion of glomus tumor. The lesion was totally excised, and histopathological examination revealed the presence of calcified deposits in the dermis. Moreover, laboratory examination, including renal function tests, serum calcium and phosphorus showed no abnormality. Idiopathic calcinosis cutis is an uncommon disorder, which is cutaneous calcification without underlying tissue injury or metabolic disorder. Tumoral calcinosis is a type of idiopathic calcinosis cutis, which usually occurs around the large joints, but rare in the fingers. Subepidermal calcified nodule is an another type of idiopathic calcinosis cutis. It is characterized by solitary hard papules on the head and extremities, which is frequently occurs in children. The other type of idiopathic calcinosis cutis is scrotal calcinosis. We herein report the case of idiopathic calcinosis cutis presenting with atypical manifestation, which occurs in fingertip of healthy male adult.

A case of giant basal cell carcinoma of the cheek

( Ji Youn Hong ),( Ji Su Lee ),( Sung Min Kim ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.1

A 59-year-old female patient presented with one year history of an enlarging left cheek mass. The mass was measured about 6 cm by 4 cm in diameter and the lesion accompanied skin color change to red and vascularization. Contrast enhanced neck magnetic resonance imaging (MRI) showed malignant tumor with suspicious involvement of the skin, but no infiltration of bone. A punch biopsy confirmed the diagnosis of basal cell carcinoma (BCC), and total whole body FDG positron-emission tomography (PET) imaging showed no suspicious metastatic hypermetabolic lesions. She referred to department of plastic surgery and was treated with wide surgical excision. BCC is the most common non-melanoma skin cancer, and its incidence is increasing worldwide. BCC generally grows slowly and has favorable prognosis. Giant BCC is a rare type of BCC, with less than 1%, which is defined as a tumor with larger than 5 cm in diameter. Contrary to natural course of general BCC, giant BCC is known to behave aggressive, which can invade and destroy the surrounding structure such as muscle and bone. However, treatment of giant BCC has not yet been established because of rarity of this tumor. Multidisciplinary approach is needed for treatment of giant BCC. We herein report the interesting case of giant BCC of the cheek.

Comparison of in vitro antifungal activities of efinaconazole and commonly used antifungal agents

( Ji Su Lee ),( Sung Min Kim ),( Ji Youn Hong ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.2

Background: Conventional antifungal agents have been used for the treatment of superficial fungal infections of skin, but have various problems in terms of side effects and efficacy. Efinaconazole is known to have superior antifungal activity against dermatophytic fungi compared to conventional antifungal drugs. Objectives: Antifungal activity of efinaconazole was measured against representative dermatophytes Trichophyton rubrum (T. rubrum), Trichophyton mentagrophytes (T. mentagrophytes), and Candida albicans (C. albicans) and compared with antifungal activity of conventional antifungal agents. Methods: We examined strains of T. rubrum, T. mentagrophytes, and C. albicans isolated from patients with tinea pedis and onycomycosis. Antifungal activity of the agents was measured using minimal inhibitory concentrations (MICs) including itraconazole, terbinafine, amorolfine, cyclopirox and efinaconazole. Results: The MIC range of efinaconazole was 0.001-0.125 μg / mL for T. rubrum, 0.0005-0.125 μg / mL for T. mentagrophytes and 0.0002-0.002 μg / mL for C. albicans. It was the lowest MIC among the antifungal agents used in this study. Conclusion: Efinaconazole has superior antifungal effect against major pathogens of superficial fungal infection compared with conventional agents.

Flavonoid silibinin induces hair growth in 3-dimensional cultured human dermal papilla cells

( Ji Youn Hong ),( Ji Su Lee ),( Sung Min Kim ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.2

Background: Alopecia is a hair loss disorder, which can have a significant psychological impact on the quality of life. Silibinin is a secondary metabolite from Silybum marianum, which is a major active component of silymarin. Previous studies have revealed that silibinin acts as an antioxidant, which can reduce the risk of cutaneous cancers. Objectives: This study aimed to evaluate the effect of silibinin on hair growth in 3-dimensional (3D) cultured human dermal papilla (DP) spheroids. Methods: Activation of serine/threonine kinase (Akt) and the wingless and INT-1 (Wnt)/β-catenin signaling pathway were measured by using the western blotting and the T cell-specific transcription factor and lymphoid enhancer-binding factor (TCF/LEF) promoter-carrying luciferase reporter assay. Expression levels of genes were determined by using quantitative real time PCR analysis. Results: Silibinin significantly increased cell viability through Akt activation in 3D-cultured DP cells. After the treatment with silibinin, the Wnt/β-catenin signaling pathway was highly activated, and the expression levels of the target genes, WNT5a and LEF1, were increased in 3D DP spheroids. Moreover, the expression levels of the signature genes of DP, such as ALPL, VCAN, FGF7 and BMP2, were significantly increased. Conclusion: Silibinin induces hair growth in 3D-cultured DP spheroids through the Akt and Wnt/β-catenin signaling pathways. This study suggests that silibinin can be a potential therapeutic option for alopecia.

MicroRNA-378b represses the expression of α -1-type 1 collagen through interference with sirtuin 6

( Ji Youn Hong ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Byung Gon Choi ),( Song Hee Han ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: Ultraviolet (UV) light induces dermis destruction by modulating the expression levels of extracellular matrix-associated genes and promotes skin aging. Sirtuin 6 (SIRT6), an established anti-aging protein, regulates collagen metabolism. However, the exact mechanism of SIRT6 expression regulated in dermal fibroblasts during the skin aging process is still unknown. Objectives: We aimed to elicit the mechanism of SIRT6 expression during the skin aging process. Methods: Human dermal fibroblasts (HDFs) were cultured and total RNA was isolated. Using real-time polymerase chain reaction (Real-Time PCR) system, mRNA expression levels of α-1-type 1 collagen (COL1A1) were detected. Protein expression levels of SIRT6 were detected using western blot analysis. Results: This study revealed that microRNA-378b (miR-378b) expression was induced in UVB-exposed HDFs, and it was inversely correlated with the mRNA expression levels of COL1A1. In addition, SIRT6, a regulator of COL1A1, was directly targeted by miR-378b and its translation was inhibited. Conclusion: This study suggests that the COL1A1 mRNA expression levels are inhibited by miR-378b through interference of translation of SIRT6 mRNA. Therefore, miR-378b may associate with skin aging and collagen expression.

Collagen type 1α synthesis pathway induced by arctiin in human dermal fibroblast

( Ji Su Lee ),( Young Ah Cho ),( Sung Min Kim ),( Ji Youn Hong ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Byung Gon Choi ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2020 대한피부과학회 학술발표대회집 Vol.72 No.1

Background: Arctiin, which is known as extract of Arctium lappa, has recently been demonstrated to improve procollagen type I synthesis and exhibits a protective effect against ultraviolet B (UVB) radiation. However, the underlying mechanism of collagen synthesis, induced by arctiin treatment, remains unknown. Objectives: The purpose of this study was to find out which pathway is involved in the synthesis of collagen type 1α 1 chain (COL1A1) by arctiin at the mRNA level. Methods: Cell viability, microRNA-378b (miR-378b) expression, relative band intensity of sirtuin 6 (SIRT6) mRNA, and relative expression of COL1A1 mRNA were confirmed according to different combination of arctiin and miR-378b concentration in dermal fibroblast. For this study, western blotting and quantitative reverse transcription polymerase chain reaction were performed. Results: Arctiin downregulated the expression of miRNA 378b, and miR-378b upregulated the expression of SIRT6 mRNA. Finally, SIRT6 induced the expression of COL1A1 mRNA. Conclusion: This study demonstrated that the arctiin-induced upregulation of COL1A1 expression is regulated by the miR-378/SIRT6 signaling pathway.

A case of pseudomyogenic hemangioendothelioma of the back misdiagnosed as epithelioid sarcoma

( Ji Youn Hong ),( Ji Su Lee ),( Sung Min Kim ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.1

A 25-year-old man referred to our dermatologic clinic with one month history of multiple nodular lesions on the back, histopathologically reported epithelioid sarcoma. A punch biopsy was performed again at our clinic, which demonstrated atypical spindle cell proliferative lesion. The tumor cells were immunoreactive for CD31, ERG, Multi-Cytokeratin (CK), INI-1, and vimentin, and were negative for S-100, SMA, EMA, and CD68. Ki-67 index was about 10% of tumor cells. Based on these results, this case is finally diagnosed as pseudomyogenic hemangioendothelioma (PHE). The patient was referred to plastic surgery department and treated with wide local excision. PHE is a rare soft tissue tumor, frequently presenting as multiple nodular lesions in the lower extremities. PHE is also known as epithelioid sarcoma-like hemangioendothelioma, which means that PHE can histopathologically mimic epithelioid sarcoma. In comparison with epithelioid sarcoma, PHE is a relatively indolent and rarely metastasizing tumor. Therefore, a definite diagnosis is important because treatment and prognosis are remarkably different. Immunochemistry is important for differential diagnosis. We herein report the case of PHE diagnosed by immunochemistry, which was misdiagnosed as an epithelioid sarcoma.

Efficacy and safety of novel hyaluronic acid filler for correction to nasolabial folds

( Ji Su Lee ),( Sung Min Kim ),( Ji Youn Hong ),( Jin Hee Kim ),( Joo Ran Hong ),( Hye In Cheon ),( Min Seok Hur ),( Beom Joon Kim ),( Yang Won Lee ),( Yong Beom Choe ),( Kyu Joong Ahn ) 대한피부과학회 2019 대한피부과학회 학술발표대회집 Vol.71 No.2

Background: To make the nasolabial folds (NLFs) less noticeable, various methods have been tried. Among them, hyaluronic acid (HA) fillers are the most effective and popular on the market. Objectives: To evaluate the clinical efficacy and safety of the new HA filler YYD701-2, we compared the properties of the new filler with Restylane® Perlane Lidocaine (Galderma, Uppsala, Sweden) in the treatment of NLFs. Methods: In multicenter, active-controlled, randomized, double-blinded, split-face, comparative, non-inferiority study, 106 subjects with moderate to severe NLFs were randomly injected with YYD701-2 in one side of NLF and Restylane® Perlane Lidocaine in the other. The efficacy was rated using Wrinkle Severity Rating Scale (WSRS) at 2, 8, 16, and 24 weeks after injection by independent evaluators. As a safety evaluation, all adverse events were analyzed. Results: The mean improvement in WSRS from baseline at week 24 was 2.47±0.56 in YYD701-2 and 2.48±0.541 in the Restylane® Perlane Lidocaine. No significant difference in WSRS was detected between them (p = 0.7040). The severity of the adverse events was mild. Conclusion: We confirmed that YYD701-2 filler is not inferior to Restylane® Perlane Lidocaine for treatment of NLFs.