Recently, exposure to sunlight is increasing due to expanded life time, outdoor leisures, and reduced sun  protective ozone layer. Sunlight can produce not only benefit but also various kinds of harmful effect, such as skin carcinogenesis, photoaging and immunologic alterations, These effects can be minimized by sunscreens. This article reviews the methods to measure a suncreens efficacy and factors influencing the measurement. I. Measurement of photoprctective efficacy 1)The sun protective factor(SPF): The SPF is defined as the ratio of the UVB doses required to produce minimal erythema dose(MED) with sunscreen applied to without it. However, the exact procedures are not estabiished and the value is varied by methods. 2)Photoprotective factor A(FFA): In spite of its clinical improtance, evaluation of UVA protection rernains a problem due to its physiologic features. The methods to measure UVA protection are by the use of erythemal, phototoxic and pigmentary rections. 3)Outdoor measurement: It is ideal to measure the photoprotectiveness outdoor but a wide variation in value results from radiance sources and environmental factors. II. Factors influencing the evaluation The radiance sources, individ zal sensitivity to sunlight, product components and various environmental fact.ors can make differences. Conclusion As more sunlight, exposure, he irnportance of photoprotection is increasing. The exact methods to measure the protectiveness of UVA and UVB should be established, especially adjusted to Korean people (Korean J Dermatol 1997;35(6): 1043-1051)

Background: The rhus has been known to be such a potent allergen that it causes severe contact dermatitis, and mary studies have tried to reveal the mechanism of allergic contact. dermatitis to urushiol. However, the mechanism of systemic contact dermatitis to urushiol is not, well-known, though the consumption of rhus as a health product and for desensitization is not unconmon in Korea. Objective : The purpose of this study was to evaluate the niechanism of systernic contact dermatis, and we carried out irnmunohistochemical stainings un the two strands of dermatitis (systemic arid,llergic contact dermatitis). Methods : The patients of systemir, contact dermatitis were divided into three groups by duration and severity of the illness according to the desired criteria. We perfor med immunohistor,hernical staining of the tissues from the pat.ients with anti CD4, CD8, CDla, ICAM-1, II,-ZR monoclorial antibodies. Results : 1. The results  were as follows. 1. The immunohistochemical staining showed that CD8 positive cell numbers in systemic contact dermatitis(18 -L 1 0) were significantly lower than those of allergic contact der matitis(37 +- 13) ( p< 0.05). 2. The expressions of HLA-DR and ICAM-1 in the keratinocytes were not significantly different. between systemic and allergic contact derrnatitis(p>0.05). Conclusion : The result suggest that lower numbers of CDH positive T cell in systemic contact dermatitis caused a reduation in the suppressor effect to the urushiol  mediated immune rection and CD8 positive T cells play an important role in systemic contact dermatitis due to rhus. (Korean J Dermatol 1997;35(6): 1052-1058)

Backgroutld: In the cutaneou; neoplasms, especially melanocytic skin lesions, the degree of t.he nuclear atypia such as the hyp rchromatism, pleomorphism, and giantism is a very impor tant factor when determining the differntial diagnosis between the malignant. and the benign turnors and the prognosis. Objective : So we measured and cornpared the nuclear atypia of the malignant melanoma, and acquired and congenital melanocytic nevi(AMN and CMN) using the computerized image analysis (IA). Methods : Five micron ser,t ons were cut from each paraffin block. The sections were Feulgen-stained and image analysis was perforrned with an AIC image analysis system. In each case, 50 lymphocytes nuclei fnim the sarne specimen slide were measured as an internal diploid control. Each 100 cells of the MM, CMN and AMN were measured and are referred to in this report as the upper part and the lower part. The morphological parameters such as mean nuclear area, coefficient of variation(CV) of the nuclear area, roundness of the nucleus and CV of the roundness were measured. For the nuclear content, mean ploidy, CV of the mean ploidy ind 2c  Deviation Index(2cI3I) were calculated and then the DNA histograms were produced. Results : Nuclear area, CV of the nuclear area, mean ploidy, CV of the mean ploidy and 2cDI were found to be significantly reat.er for rnalignant melanoma than for CMN and AMN. The nuclear area of AMN is significantly lar ger than that of CMN and there were no significant differences between the uper and the lower part.s of three melanocytic lesions in any of the measured parameters. Conclusion . The results of o ir study suggest that the IA of the melanocytic cells might reflect the biologic behavior rnore sensitively t,han do clinical or histologic criteria, therefore important information for differentiating thi benign and the malignant melanocytic lesions may be obtained by the DNA profile and morphomi try on Feulgen st,ained tissue specirnens using IA.(Korean J Dermatol 1997;35(6): 10591065)

Background: The incidence of herpes zoster is higher among patients with impaired cell  mediat,ed immunity. Herpes zoster skin lesions frequently become more severe and run a more protracted course in such patients. Objective : This study aimed to firstly elucidate whether there are changes in cell  mediated immunity, even in immunocompetent, patients with herpes zoster, and secondly to investigate relationships between these change and the clinical appearance of herpes zoster. Methods : T lymphocyte sub;et,s in peripheral blood and delayed hypersensitivity reactions using the Multitest CMI kit were measured in 33 healthy patients with herpes zoster and 28 controls. Results : As compared with controls, there was a slight decrease in percentages of CD4 lym-phocytes, a significant decr eas in percentages of CD8 lyrnphocytes, and a slight increase in CD4/ CD8 ratios in the acute phasr of herpes zoster. The percentages of CD3 lymphocytes were also significantly decreased. Baseg i)n the severit,y of the skin lesion, t.her e was a significant increase in duration of acute herpetic pain. However, there were no signigicant differences in percentages of T lymphocyte subsets based on the severity of skin lesion and duration of acute horpetic pain. In delayed hypersensitivity rea.tions with the Multitest" CMI kit, the intensity and frequencies of positive reactions were signific,intly decreased in the patients group. Conclusions . There are sigr.ificant changes in peripheral blood T lymphocyte subsets and delayed hypersensitivity reactions even in other wise healthy patients. (Korean J Dermatol 1997;35(9): 1066-1073)

Background : Inverted follicular keratosis has distinctive histopathological features and is infre quently encountered by dermatologists. To date, the pathogenesis of inverted follicular keratosis has not, been concluded. Many authors have suggest,ed several theories for the nature of invert.ed follicular keratosis including vearuca vulgaris with squamous eddies, irritated seborrheic keratosis and dist,inctive follicular tumors. Objective : It is the purpose of this study to observe and compare the clinical features of in verted follicular keratosis with previous studies and evaluate the possible relationship between in verted follicular keratosis and human papillomavirus to clarify the nature of this condition. Methods : We studied 9 patients with inverted follicular keratosis for clinical features including the duratiori of the disease, the location and size of the lesions, the clinical impressions at the first visit and we made a record of the patients age and sex. To evaluate the relationship be tween inverted follicular kerato is and the human papillomavirus, we performed immunohistochvm ical staining using polyclonal antibodies to the human papillomavirus common antigen. We also used the polymerase chain relation to detect hurnan papillomavirus DNA in inverted follicular keratosis from paraffin embedded tissue preparation. 
Results : 1. Seven of the 9 patients,vere male and the ages ranged fiom 36 to 77 years(mean 53 years). The lesions were situat d on the face(4/9),abdomen(1/9), back(1/9), chest(1/9), scapular area(1/9) and leg(1/9). The average size of the lesions was 1.5 cm. Verruca vulgaris was the most common clinical diagnosis(3/9), followed by seborrheic keratosis(2/9), soft fibroma(2/9), pigmented nevi(1/9), and granioloma pyogenicum(1/9). 2. Immunohistochemical stainiiigs using polyclonal antibodies to the human papillomavirus common antigen were negative for all 9 cases. 3. Polymerase chain reaction; using primers for human papillomavirus DNA were negative for all 9 cases. Conclusipn : In general, our linical findings are similar to those of others in previous studies. Our results of immunohistocheriiical staining and the polymerase chain reactions suggest, that in vert,ed follicular keratosis is ncl, related to the human papillomavirus. Further investigat.ions inf'o the nature of invert,ed follicular keratosis, should be centered on initated seborrheic keratosis and distinct follicular tumor s. (Korean J Dermatol 1997;35(6): 1074-1081)

This stuc1y was conducted to evaluate the therapeutic effect of immunotherapy on verruca plana. Forty-four patients with verruca plana were tried with dinitrochlorobenzene(DNCB) and diphenylcyclopropenone(DPCP) by topical application on the norinal uninvolved skin of the inner arms for sensitization and challenge. The lesions were challenged in weekly intervals after sensitization. The results obtained in this study are as follows. 1. Mean age of our patients was 20-year-old and sex ratio was about 1:2 (14 of male, 30 of female). 2. Tbe sites of the lesion weve face (60.9%), neck (7.2%), trunk (2.9%), arm (li3.0%), hand (11.6% ), leg (4.3% ). 3. Thirty  two patients (72.7%) from 44 cases were completely cured after DNCB (81.3%) and DPCP (67%) treatment and iesions on younger patients showed a better response than those of of older patients(p<0.05). 4. There were no statistic relationship between duration of the lesions and therapeutic response. 5. Average challenge number after sensitization was 3.77 in DNCB, 2.26 in DPCP, respectively. 6. Sensitization rates in the cured patients were to treat verruca plana 94.7% (18/19) in DNCB, 76.9% (10/13) in DPCP, respectively. (Korean J Dermatol 1997;35(6): 1082-1087)

Background: Apoptoss plays a major role in cellular proliferation and differentiation in tumor cells. Bcl-2, proto-oncogene, is known to inhibit apoptotic cell death of tumor cells. The high expression of bcl-2 in human melanoma cells over transforrned keratinocytes has been reported. The Loton group indicated that the growth of human melanoma cells exposed to ret.inoids was inhibit ed and their cellular melanin content incrensed over that of the untreat,ed ce1Ls. The Veis group reported that bcl-2 defieient mice showed hypopigmented hair. Which suggests that bcl-2 may in volve melanogenesis. The Above mentioned findings may suggest that. bcl-2 and retinoids may play a role in melanoms biology. Objective : We under ook this study to elucidate a possible relationship between retinoids and bcl-2 expvessions in human melanoma cell lines. Methods : We analysed bcl-2 expressions from SK 28 cells(melanoma cell lines) after pretreat ment with retinoids using flow cytometry and imtnunoblotting. Results : 1. In the results of the preliminary studies, we found that cultured human keratinocytes, fibro blasts and melanocytes n the resting state showed expressions of bcl-2. The latter showed a four fold expression of bcl-2. 2. Expression of bcl-2 was detected in SK 28, a human melanoma cell line, in the resting state. 3. After incubation with isotretinoin or etretinate treatment at 37'C,  for 48 hours, this treated group showed a more ir creased expression of bcl-2 than the control group. Conclusion : Our data may explain that the mechanism of ret.inoids indur,ing inhibition of mela noma cell growth may be partly due to upregulation of bcl-2 expression. The high base-line ex pression of bcl-2 in melanoma cells may tell us why these pigment cells can survive against oxi dative products generated during melanogenesis. (Korean J Dermatol 1997;35(6): 1088-1094)

Background: The patcl test is widely used for diagnosis of allergic contact dermatitis. However, it is sometimes difficiilt or even impossihle to differentiate between allergic and irritant reactions in patch test readings. The achievernent of valid results from the patch test require intelligent and careful patch testing and physirians with skills and experiences. Objective : The purpos of this study was to assess the frequency, age and sex distr ibution, and the seasonal variatioii of irritant. and lost reactions in standard patch tests. Methods : Patch test records of day 2 and day 4 were reviewed and analysed. Frequency of inritant and lost reactions were analysed by allergen, age, sex and season. Results : A total 212 c ses of standard patch test records(rnale 69, female 143) were analysed. The results were as follovs ; 1. The over  all frequency of lost reactions in the standard patch test were 33.5 percents and that of irritant reactions were 8.0 perr.ents. 2. The frequency of lost reactions was lower in the age groups under twenty(7.7%) than in the older age groups(35.5%). However, there was no significant difference het,ween the age groups over the third dec ide. 3. The seasonal variation was evident in lost reactions. The order of frequency was summer(45. 0% ), winf,er(33.7% ), spri,ig and fall(2l.1% ). 4. The order of frequency of lost reactions in the stclndard patch allergen was captan(5.7%), potassium dichromate(5.2%), cobalt chloride(4.7%), mercury amrnoniurn chloride(3.8%) c3lld wool alcohol(3.8%) Conclusion : Our result, show a relatively high frequency of lost and irritant. reaction in the standird patch test, and uggest second readings in the patch test would he of value. (Korean J Dermatol 1997;35(6): 1095-1100)

Background: The patients of trichotillomania seem to have received much attent.ion based on patients behavioral psychologic;l aspects, but most of the patients ar e met in dermatological clinics. Dermatological observation of the lesion dose not seem to not sufficient. Qbject: The purpose of this study is to exarnine clinical and histopathological characteristics of the lesion of trichotillomania. Methods : We have observed 28 cases of the trichotillornania and exarnined their cutaneous lesions and histopathological featwres. Histopathological examination with vertical serial sections was done in 21 cases. Because hai folllicles are independent of each other and a usual 5 thickness vertical sect,ion shows only ver y limited numbers of the hair follicles, authors accomplished sectioning of the biopsied scalp tisue to have 300 serial sections cut and 60 representative sections observed to allow the fullest qiiantitative and qualitative examinations of the follicular pathology of the lesion. Results : The important featuies are as follows. 25 cases(89.2%) were under 18 years old with a slight male predorninance(M:F=1.3:1). Only in 2 cases, psychiatric consultation was made. The degree of involvement was vari ble from less than 5%(6 cases) of the scalp up to 100% involvement of the scalp(3 cases). Thr rnean duration of illness was 12.5 months. The involved hair follicles showed one of the following five roots of hairs they are new hairs with tapered ends, broken short hairs, vellus or intermediate hairs, comedone-like hair bodies or empty follicle orifices. Microscopical observation of thr epilat,ed hairs was done in 16 cases, of which in 13 cases there were no telogen roots of terminal hairs, The histopathological results were as follows : 1. Catagen follicles were incr:ased in 20 cases(95.2%). The actual number of catagen follicles was 1386(37.5%) out of a tota 3695 follicles observed in the total examined slides. 2. Trichornalacia were seen ir 11 cases(52.4%). The actual number of hairs with trichomalacia was 195(10.5%) out of a total 1005 hair canals observed. 3. Pigment clumps of the follicular infundibula were seen in 9 cases(42.9%). The actual num- ber of the pigment-laden infundibula was 148(17.9%) out of a total 826 infundibula observed. 4. Destruction of the hair canal wall were seen in 4 cases(19.0% ). The actual number of destructed hair canal wall was 190(10.2%) out of a total 1863 hair canals observed. Hernorrhage around the follicles was not seen. Conclusion : The involved areas of trichotillomania were varied in size up to the whole scalp and showed four different type., of hairs. Histopathologically catagen follicles increased in almost all cases with 37.5% of all follicles examined. Trichomalacia, pigmented clumps, and the destruction of hair canals were seen by less frequently. (KOrean J Dermatol 1997;35(B): 1101-1109)

Background: In both normal tissue development and malignant cell growth, the maintenance of cell numbers reflects a balance between cell proliferation and cell death. Excessive growth may result from uncontrolled cellular proliferation or limited cell death. The growth process of squa mous cell carcinorna(SCC) has recently been reported to differ from that of basal cell carcinoma (BCC). Several reports have suggested that the normal-appearing, overlying epidermis might be a proliferative and be a precursor lesion of BCC. SCCs occur in burn scars, chronic ulcers, and chronic sinus but the najority of SCCs are actinic in origin. It. is possible to develop subsequent. skin cancer from the normal-appearing epidermis adjacent to SCC due to chronic sun-exposure. Objective : The purpose of this study was to investigate growth dynamics of non-melanorna skin cancers and characteristics, including the carcinogenic property, of the normal  appearing epidermis overlying and acljacent to non  rnelanoma skin cancers. Methods : We compared expressions for p53, PCNA, bcl  2, and TGF-a in 21 BCCs and 8 SCCs by irnmunohistochi.mical staining with a labelled strept,avidin  biotin complex(LSAB) method. Results . The results were as follows. 1) Expressions for p53 and PCNA within the tumor remarkably increased and the distribution pattern of expression for p53 was not always consistent with that for PCNA. 2) An expression the bcl-2 was increased in half of the BCCs, but not in all of the SCCs. 3) The epidermis overlying the BCC showed increased expressions for p53, PCNA, and TGF-a. 4) The epidermis adjacent to the SCC showed increased expressions for p53, and PCNA in a few of cases. Conclusion : We suggest that a neoplastic transformatiqn in BCC is caused by extended cell survival rather than ini:reased cell proliferation, but in SCC it. is caused by other mechanisms, and that the proliferativ activity in the epiderrnis overlying BCC is different from the normal epidermis and maybe repr'sents carcinogenic activity of the epidermis. (Korean J Dermatol 19()7;35(6): 1110-1120)