FC 1-4 : A survey of attitudes, knowledge, and behavior regarding sun exposure and sunscreen use

( Sih Yeok Jang ),( Hyeong Ho Ryu ),( Eun Jung Hwang ),( Hyun Sun Park ),( So Yun Cho ),( Hyun Sun Yoon ) 대한피부과학회 2013 대한피부과학회 학술발표대회집 Vol.65 No.2

Background: Although sunscreen is used as a primary strategy to prevent sunburn, photoaging and skin cancer, only a few people regularly use sunscreen. Objectives: To investigate the awareness of effects of sunlight, the extent of sun exposure, and the behaviors about sunscreen uses in Korean. Methods: A questionnaire was administered 255 adult patients visited Dermatology Department at Seoul National University Boramae Hospital. It included questions about the awareness of benefit or harm of sunlight, perceived and actual extent of sun exposure, the use of sun-protective methods including sunscreen. Results: Sun exposure was chosen as the major cause of dyschromia (61.2%), skin cancer (62.8%) and wrinkle (28.6%). Respondents were likely to underestimate the extent of sun exposure. On average, quite a few respondents stated that they were exposed to sunlight more than one hour per day (23.1% on weekdays, 53.4% on weekends). But, only 8.7% thought that their sun exposures were problematic and 62.2% of respondents considered moderate sunlight exposure good for health. People`s sun protective behaviors were inadequate: only 30.8% used sunscreen regularly; 18.4% have never used sunscreen. SPF was the most important factor choosing sunscreen and 86.0% used sunscreen labeled SPF over 30. In contrast, only 40.3% used PA+++ sunscreen. Conclusion: Despite a fairly good knowledge about harmful effects of sunlight, people underestimated the risks of their sun exposure and behaviors were suboptimal.

한국인에서 일광노출과 자외선차단제에 대한 인식과 사용 행태 연구

장시혁 ( Si Hyeok Jang ),박현선 ( Hyun Sun Park ),조소연 ( So Yun Cho ),윤현선 ( Hyun Sun Yoon ) 대한피부과학회 2015 대한피부과학회지 Vol.53 No.1

Background: Although sunscreen is used as a primary strategy for the prevention of sunburn, photoaging, and skincancer, few people regularly use sunscreen. Objective: To investigate awareness regarding the effects of sunlight, the extent of sun exposure, and sunscreen usebehaviors in Korean subjects. Methods: A questionnaire was administered to 467 adult patients who visited the Dermatology Department at SeoulNational University Boramae Hospital. The questionnaire covered demographic characteristics, causes of wrinkles,sunspots, and skin cancer, awareness of the harmful effects of sun exposure, perceived and actual extent of sunexposure, and the use of sun-protective methods including sunscreen. Results: Sun exposure was selected as the major cause of age spots (60.6%), skin cancer (60.9%), and wrinkles(25.9%). Respondents were likely to underestimate the extent of sun exposure. On average, quite a few respondentsstated that they were exposed to sunlight for more than one hour per day (22.7% on weekdays, 52.4% onweekends). However, only 9.4% of respondents thought that their sun exposure was problematic and 62.7% ofrespondents considered moderate sunlight exposure healthy. Respondents`` sun-protective behaviors were inadequate:only 29.8% used sunscreen regularly, and 16.5% have never used sunscreen. SPF was the most important factor inchoosing sunscreen, and 83.3% used a sunscreen with a labeled SPF over 30. By contrast, only 34.6% ofrespondents used PA+++ sunscreen. Conclusion: Despite fairly good knowledge regarding the harmful effects of sunlight, subjects underestimated therisks of their sun exposure and sun-protective behaviors were suboptimal. Education on the risk of UV exposure andeffects of sunscreen is still needed. (Korean J Dermatol 2015;53(1):16∼22)

Long-term treatment of topical estrogen to the sun-exposed facial skin of postmenopausal women induced matrix metalloproteinase-1 expression, leading to facial wrinkles aggravation: 24-week results from a double-blind, vehicle-controlled, randomized study

( Hyun Sun Yoon ),( Se Rah Lee ),( Soyun Cho ),( Jin Ho Chung ) 대한피부과학회 2012 대한피부과학회 학술발표대회집 Vol.64 No.3

Atypical pigmented basal cell carcinoma mimicking traumatic pigmented tattoo

( Ji Won Kim ),( Hyun-sun Park ),( Hyun-sun Yoon ),( Soyun Cho ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.1

Basal Cell Carcinoma, the most common type of skin cancer in humans, usually develops in the sun-exposed area of head and neck. A 63-year-old woman presented with 1-year history of a bean-sized, slightly protruded bluish dermal patch in her right para-nasal area, and it gradually increased in size after she perceived its presence. It looked like traumatic pigmented tattoo because of bluish color and flat patchy features. A punch biopsy was performed, and the lesion was diagnosed as a basal cell carcinoma (BCC). Histopathologically, melanophages were seen scattered between typical basaloid BCC tumor nests in the reticular dermis, making the lesion appear similar to a traumatic pigmented tattoo by Tyndall effect. Typically pigmented BCC appears as a hyperpigmented, translucenet papule which may also have eroded borders. The patient only showed bluish colored patch without eroded borders, making it appear clinically similar to a pigmented tattoo. Herein, we report an interesting case of pigmented BCC which mimicked traumatic pigmented tattoo but was confirmed to be a BCC by biopsy.

Claudin-1 expression decreases with increasing pathologic grade in actinic keratosis and may be used as a marker of high-risk actinic keratosis

( Ji Su Lee ),( Hyun-sun Park ),( Hyun-sun Yoon ),( Soyun Cho ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: Actinic keratosis (AK) is a common sun-induced skin disorder of importance for the progression to invasive squamous cell carcinoma. However, there is still no good way to predict high risk AK. Objectives: To identify markers which reflect the biologic behavior of AK and to understand the pathogenesis of AK Methods: A total of 52 patients with AK and site-matched 17 normal controls were included. We evaluated solar elastosis and immunohistochemical features using the following antibodies: p53, vitamin D receptor (VDR), claudin-1, and Langerin. Results: Solar elastosis increased and Langerhans cell (LC) density decreased with aging in both patients and controls. Solar elastosis and p53 expression were higher and VDR expression was lower in patients than controls; however, they showed no statistical difference in relation to the pathologic grade of AK. Claudin-1 expression gradually decreased from normal control to severe AK and decreased in the areas with epidermal atypia. LC density in severe AK was significantly lower than in normal control and mild AK; no difference in LC density was seen among control, mild AK and moderate AK. Conclusion: Claudin-1 can be a useful marker of pathologic severity of AK. In contrast, p53 increases and VDR decreases in AK not in gradual manner but in the early steps of carcinogenesis. LC density is relatively maintained in AK until it reaches severe dysplasia.

지루각화증의 임상 및 병리조직학적 고찰

박세영 ( Se Young Park ),박현선 ( Hyun Sun Park ),조광현 ( Kwang Hyun Cho ) 대한피부과학회 2011 대한피부과학회지 Vol.49 No.1

Background: Although seborrheic keratosis is one of the most common epidermal tumors, there are only rare studies on the clinicohistopathologic features of seborrheic keratosis in Korea. The majority of cases of typical seborrheic keratosis can be clinically differentiated with ease from other dermatoses such as melanocytic nevi, lentigo, basal cell carcinoma and melanoma. However, its differential diagnosis can sometimes be difficult. Objective: This study was designed to investigate the clincohistopathologic characteristics of seborrheic keratosis, the frequency of biopsy and the accuracy of making the clinical diagnosis, as well as to analyze the cases where there is a mismatch between the clinical diagnosis and the histological diagnosis. Methods: We conducted a retrospective study and we searched for patients who were clinically diagnosed as having seborrheic keratosis between January 2000 and December 2008. The search found 1,248 patients and the patients were divided into two groups: a non-biopsy group (n=891) and a biopsy group (n=357). The clinical features, including age, gender, the anatomic site of lesion and the treatment method, were investigated in each group. In addition, the frequency of biopsy, the accuracy of the clinical diagnosis and the histopathological features were studied in the biopsy group. Results: Between the two groups, we found that the clinical features, including the proportions between the involved body sites, such as trunk/face, and the treatment methods were different. However, these differences might be partly attributed to the clinical decisions such as the frequency of performing biopsy for making the differential diagnosis of skin malignancy. In both groups, the most frequent age period was in the seventh decade and the most common anatomical site was the face. Only one-third of patients who were clinically diagnosed as having seborrheic keratosis received biopsy for histopathologic confirmation and the lesions were mostly located on the face. The clinical diagnosis matched the histological diagnosis in 282/357(79.0%) patients. In 75 patients who revealed a mismatch between the clinical and histological diagnosis, the skin lesion most frequently involved the face(57.3%) and the most common final diagnosis was basal cell carcinoma (13.3%). The frequency of a mismatch for the sun-exposed lesion was significantly higher than that of the non-sun exposed lesion (p=0.035). Conclusion: We present the clinical and histopathological features of seborrheic keratosis. If the lesion is presented with an atypical appearance or it located on a sun-exposed area and so it requires a differential diagnosis from other premalignant diseases or cutaneous malignancies, then we should perform a biopsy to make the differential diagnosis. (Korean J Dermatol 2011;49(1):12~19)

Modeling of CO₂ Emission from Soil in Greenhouse

Dong Hoon Lee,Kyou Seung Lee,Chang Hyun Choi,Yong Jin Cho,Jong-Myoung Choi,Sun-Ok Chung 한국원예학회 2012 원예과학기술지 Vol.30 No.3

Greenhouse industry has been growing in many countries due to both the advantage of stable year-round crop production and increased demand for fresh vegetables. In greenhouse cultivation, CO₂ concentration plays an essential role in the photosynthesis process of crops. Continuous and accurate monitoring of CO₂ level in the greenhouse would improve profitability and reduce environmental impact, through optimum control of greenhouse CO₂ enrichment and efficient crop production, as compared with the conventional management practices without monitoring and control of CO₂ level. In this study, a mathematical model was developed to estimate the CO₂ emission from soil as affected by environmental factors in greenhouses. Among various model types evaluated, a linear regression model provided the best coefficient of determination. Selected predictor variables were solar radiation and relative humidity and exponential transformation of both. As a response variable in the model, the difference between CO₂ concentrations at the soil surface and 5-㎝ depth showed are latively strong relationship with the predictor variables. Segmented regression analysis showed that better models were obtained when the entire daily dataset was divided into segments of shorter time ranges, and best models were obtained for segmented data where more variability in solar radiation and humidity were present (i.e., after sun-rise, before sun-set) than other segments. To consider time delay in the response of CO₂ concentration, concept of time lag was implemented in the regression analysis. As a result, there was an improvement in the performance of the models as the coefficients of determination were 0.93 and 0.87 with segmented time frames for sun-rise and sun-set periods, respectively. Validation tests of the models to predict CO₂ emission from soil showed that the developed empirical model would be applicable to real-time monitoring and diagnosis of significant factors for CO₂ enrichment in a soil-based greenhouse.

Modeling of CO₂ Emission from Soil in Greenhouse

Lee, Dong-Hoon,Lee, Kyou-Seung,Choi, Chang-Hyun,Cho, Yong-Jin,Choi, Jong-Myoung,Chung, Sun-Ok Korean Society of Horticultural Science 2012 원예과학기술지 Vol.30 No.3

Greenhouse industry has been growing in many countries due to both the advantage of stable year-round crop production and increased demand for fresh vegetables. In greenhouse cultivation, $CO_2$ concentration plays an essential role in the photosynthesis process of crops. Continuous and accurate monitoring of $CO_2$ level in the greenhouse would improve profitability and reduce environmental impact, through optimum control of greenhouse $CO_2$ enrichment and efficient crop production, as compared with the conventional management practices without monitoring and control of $CO_2$ level. In this study, a mathematical model was developed to estimate the $CO_2$ emission from soil as affected by environmental factors in greenhouses. Among various model types evaluated, a linear regression model provided the best coefficient of determination. Selected predictor variables were solar radiation and relative humidity and exponential transformation of both. As a response variable in the model, the difference between $CO_2$ concentrations at the soil surface and 5-cm depth showed are latively strong relationship with the predictor variables. Segmented regression analysis showed that better models were obtained when the entire daily dataset was divided into segments of shorter time ranges, and best models were obtained for segmented data where more variability in solar radiation and humidity were present (i.e., after sun-rise, before sun-set) than other segments. To consider time delay in the response of $CO_2$ concentration, concept of time lag was implemented in the regression analysis. As a result, there was an improvement in the performance of the models as the coefficients of determination were 0.93 and 0.87 with segmented time frames for sun-rise and sun-set periods, respectively. Validation tests of the models to predict $CO_2$ emission from soil showed that the developed empirical model would be applicable to real-time monitoring and diagnosis of significant factors for $CO_2$ enrichment in a soil-based greenhouse.

한국 전통장류가 한우 반힘줄모양근(M. Semitendinosus)으로 제조한 건염햄의 육질 특성에 미치는 영향

성필남,조수현,강근호,김동훈,박범영,강선문,박경미,Seong, Pil-Nam,Cho, Soo-Hyun,Kang, Geun-Ho,Kim, Dong-Hoon,Park, Beom-Young,Kang, Sun-Moon,Park, Kyoung-Mi 한국축산식품학회 2013 한국축산식품학회지 Vol.33 No.6

This study was conducted to develop a processing method for dry-curing beef ham with Korean traditional sauces and to investigate the quality properties of the dry-cured beef hams. Semitendinosus muscle from Hanwoo was spread with sundried salt (C), sun-dried salt mixed with red pepper paste (T1), and sun-dried salt mixed with soybean paste (T2), and inserted into washed Hanwoo large intestine. It was then dried and fermented for 75 d. Moisture contents of the hams were 46-48%, without any significant differences. T1 showed the lowest pH among the three dry-cured hams, while water holding capacity (WHC) of T2 was found the lowest (p<0.05). In mechanical color determination, C showed higher CIE $a^*$ and CIE $b^*$ than T1 and T2 (p<0.05), however CIE $L^*$ did not show any significant difference. In texture, T1 demonstrated significantly lower springiness than C (p<0.05). The sensory properties of all dry-cured hams did not show any significant difference, but T1 indicated a higher taste, saltiness and overall acceptability than others, whereas C gathered the highest score in color and flavor. In conclusion, the dry-curing by combination of sun-dried salt mixed with red pepper sauce (T1) showed higher quality properties of the Hanwoo dry-cured ham. 우리나라 전통장류를 건염햄 제조에 접목한 건염햄의 제품을 개발하기 위해 염지과정에서 첨가한 고추장과 된장이 건염햄 품질에 미치는 영향을 조사하고자 실시하였다. 천일염(C), 천일염+고추장(T1), 천일염+된장(T2)을 한우의 반힘줄모양근(m.emitendinosus)의 표면에 골고루 발라주고 세척한 한우 대장에 충진한 후 75일 동안 건조 및 발효시켰다. 한우 반힘줄모양근 건염햄 품질을 조사한 결과, 건염햄 수분함량은 46.45-48.04% 수준으로 유의적인 차이는 없었다. T1은 모든 처리구 중에서 pH가 가장 낮았고 T2는 WHC가 가장 낮았다(p<0.05). 기계적 육색 측정에서 C가 $a^*$와 $b^*$가 전통장류 처리(T1, T2)보다 높았으나(p<0.05), $L^*$은 유의적인 차이가 없었다. 조직감에서 T1은 C보다 탄력성이 유의적으로 낮았다(p<0.05). 관능평가 결과 모든 처리구에서 유의적인 차이가 없었고 C는 제품색과 향미가 높은 점수를 받은데 반해, T1은 높은 맛, 짠맛, 그리고 전체적 기호도가 다른 처리구에 비해 높았다.

Differentiation of Desmoplastic Spitz Nevus from Similar Conditions

( Min-woo Kim ),( Ji Soo Lim ),( Yun Seon Choe ),( Jung Ho Kim ),( Hyun-sun Yoon ),( Soyun Cho ),( Hyun-sun Park ) 대한피부과학회 2016 대한피부과학회지 Vol.54 No.9

The diagnosis of classic Spitz nevus with characteristic histopathologic findings is often straightforward, but unusual variants can cause diagnostic difficulties. Desmoplastic Spitz nevus (DSN) is of particular importance, as its differential diagnosis from other diseases, including desmoplastic malignant melanoma (DMM), is essential but often difficult¹. A 38-year-old Caucasian woman presented with a 6-mm brownish papule of unknown onset on the dorsum of her left hand (Fig. 1A). She did not report any change in the papule size, trauma history, or related symptoms, but she wanted to have the lesion removed. Punch excision of the specimen revealed proliferation of individual spindle and epithelioid cells with scanty pigmentation within dense colla-genous dermal stroma (Fig. 1B, C). The specimen was focal positive for S-100 and HMB-45, positive for Melan-A, and 1% positive for Ki-67 (Fig. 2A∼C). The lesion did not recur after punch excision at the 1-year follow-up. Since its first report in 1975, there have been only a few case series of DSN owing to the rarity of this disease and its under-recognition, except for intermittent case reports^1-3. DSN usually presents as a small red-brown papule on the trunk and extremities. It can occur at any age, but is mostly observed in young adults, with a slight female predominance. The distinctive histopathologic features of DSN―an intradermal growth pattern of large spindle or epithelioid nevus cells embedded in a fibrotic stroma, sparse melanin pigment, no junctional activity, no Kamino bodies, no prominent nest formation―can aid its differentiation from clinical simulators. Additionally, immunohistochemistry is essential for a differential diagnosis. DSN tests positive for S-100, Melan-A, and HMB-45, whereas dermatofibroma is negative for all three³. Hypomelanotic blue nevus shows uniform positivity for HMB-45, whereas DSN shows differential expression in most spindled cells3. The distinction between DSN and DMM is the most important. DMM is more common in elderly patients and tends to occur on sun-damaged head and neck areas. It also shows cellular atypia, strong mitotic activity and Ki-67 expression, less frequent S-100 and Melan-A positivity, and almost exclusive negativity for HMB-45^2,3. Some researchers regarded DSN as an end stage of Spitz nevus that had lost continuity with the epidermis and undergone fibrosis. Paniago-Pereira et al.² also reported that DSNs occurred in patients older than 30 years. These findings suggest that desmoplasia might be an aging process of Spitz nevus. However, Barr et al.1 found no significant difference in patient age, disease duration, or trauma history between patients with DSN and common variants of Spitz nevus, and suggested that desmoplasia may be a tumor-induced reactive stromal induction rather than a regressive phenomenon. The pathogenesis of desmoplasia has not yet been clearly elucidated. Moreover, it is controversial whether DSN should be regarded as a variant of Spitz nevus or whether it belongs to a spectrum of desmoplastic nevus as a distinctive entity^3,4. Some researchers5 suggested strict diagnostic criteria for de-smoplastic nevus, including greater cellularity in the super-ficial portion, and a mixture of melanocytic nevus cells, ovoid and dendritic melanocytes, and spitzoid melanocytes. Further, they mentioned that lesions in which one particular type of melanocyte predominates over others are more likely to represent DSN. Dermoscopic findings can also aid the distinction, because DSN shows dotted vessels and reticular depigmentation whereas desmoplastic nevus demonstrates a delicate pigment network over a pinkish background⁴. Although it is regrettable that we did not acquire dermoscopic image to support the diagnosis, our case overall seems more com-patible with DSN. However, the probability of a morphologic spectrum that embraces DSN and desmoplastic nevus cannot be excluded, and requires further studies. Here, we report an unusual desmoplastic variant of Spitz nevus with a literature review, and propose keynotes for differential diagnosis from its simulators, especially DMM.