This study was to evaluate the skin sensitization of potassium hydroxide (KOH) by the guinea pig maximization test. In the preliminary test, the induction and challenge dose of KOH were determined as 1.0 and 0.2%, respectively. Guinea pigs were sensitized with intradermal injection of 0.1ml KOH for 24 h. After 1 week, 1.0% of KOH was treated on the site of injection and 0.2% of KOH was challenged 2 weeks later. The average skin reaction evaluated by erythema and edema on the challenge sites and sensitization rate in the KOH-treatment group at 24 h were 0.0 and 0%, respectively, which are substantially low compared with in the 2,4-dinitrochlorobenzene-treatment group (positive control group) (average skin reaction: 3.0, sensitization rate: 100%) and identical with in the distilled water-treatment group (negative control group), representing a weak sensitizing potential. The average skin reaction and sensitization rate observed at 48 h were 0.0 and 0% in the KOH-treatment group, respectively, and 2.0 and 100% in the positive control group, respectively. It was concluded that 1.0% of KOH classified to Grade I, induced no sensitization when tested in guinea pigs.

This study investigated the antibacterial activity against Staphylococcus (S.) aureus, Salmonella (S.) typhimurium and Escherichia (E.) coli O157:H7, and skin irritation in New Zealand white rabbits using methanol extracts of Curcuma (C.) aromatica Salisb. The minimum inhibitory concentration (MIC) of C. aromatica extracts against S. aureus, S. typhimurium and E. coli O157:H7 was 0.250, 0.250 and 0.125 mg/ml, respectively, and the minimum bactericidal concentration (MBC) of the extracts against S. aureus, S. typhimurium and E. coli O157:H7 was 0.50, 0.50, 0.250 mg/ml, correspondingly. From the skin irritation test, extremely minor erythema and very slight edema were formed at 24 h after application of the extracts on the skin on abraded lesions of 2 and 1 rabbits, respectively. The primary irritation index score was estimated to be 0.13 indicating non-irritation. In conclusion, this study suggests that C. aromatica extract has the antibacterial activity against major food-borne pathogens and is not irritant to skin.

Despite the various effects on the health of Chamaecyparis obtusa essential oil (COEO), an adverse effect on the skin has recently been reported. Therefore, in this study, the skin sensitization test of COEO was conducted to confirm the skin safety of the essential oil by the guinea pig maximization test. Guinea pigs were sensitized with intradermal injection of 0.1ml COEO for 24 h. After 1 week, 5% of COEO was treated on the site of injection and 2% of the essential oil was challenged 2 weeks later. The average skin reaction evaluated by erythema and edema on the challenge sites and sensitization rate in the COEO-treatment group at 24 h were 0.0 and 0%, respectively, which are substantially low compared with in the 2,4-dinitrochlorobenzene-treatment group (positive control group) (average skin reaction: 3.0, sensitization rate: 100%) and identical with in the olive oil-treatment group (negative control group), representing a weak sensitizing potential. The average skin reaction and sensitization rate observed at 48 h were 0.0 and 0% in the COEO-treatment group, respectively, and 2.0 and 100% in the positive control group, respectively. It was concluded that 5% of COEO classified to Grade I, induced no sensitization when tested in guinea pigs.

본 연구에서는 교량기초 말뚝의 부주면마찰력 시험을 통하여 연약지반에 타설된 강관말뚝의 부주면마찰력을 측정하였으며 장기적인 마찰응력의 관측시험을 통하여 경제적인 상부구조물 시공시기를 판단하였다. 본 연구의 결론은 다음과 같다. (1) 연약지반에서 부마착력의 크기는 침하속도가 클수록 크게 나타났다. (2) 마찰력의 관계 그래프에서 마찰응력의 증감이 없는 시기를 확인하여 상부구조물 시공시기를 판단할 수 있었다. (3) 말뚝정재하시험결과와 부주면마찰력 시험결과를 비교해 본 결과 항타 직후의 부주면마찰력은 재하시험 시의 마찰응력보다 크게 나오는 것으로 판단되며 15일 경과후의 측정값은 비슷하게 나오는 것으로 판단되었고, 이론식에 의한 결과와도 비슷하였다. (4) 부주면마찰력의 장기관측기법을 사용하면 부주면마찰력이 발생하고 있는 중이라도 적절한 상부구조물의 시공시기를 파악할 수 있어 경제적인 시공관리가 가능한 것으로 판단된다.

The purpose of the present study was to investigate differences in the sensitizing potential of Rhus Veniciflua(Rhus-II), when tested by the guinea pig maximization test(GPMT) and Freund's complete adjuvant test(FCAT) with an identical, intradermal induction concentration. A new grading. classification of the sensitization potential is proposed. The GPMT was conducted according to OECD guideline #406, using a multiple-dose design and test results were analysed with logistic regression analysis. During the induction stage, we injected intradermally each three site 0.1 ml( 1mg/animal) test material. 0.1ml complete Freund's adjuvant and 0.1ml the test agent emulsified in the adjuvant. 7 days later, we induced weak sensitization with 10% sodium lauryl sulfate(SLS) and applide 1ml(10mg/animal) test agent topically on the same site and made a tight occlusion. 14 days later we challenged with 1ml(10mg/animal) of test material on the flank and observed ant 24 hours and 48 hours later. The results were also observed 0% at 24 hours challenge. The results observed 48 hours after challenge were the identical. These data indicated that. although Rhus-II is a no contact allergen. It was reported that the skin sensitization by Rhus-II was not detected the skin sensitization in the guinea pig maximization test (GPMT). Consequently, it was confirmed that Rhus-Il had no contact allergic sensitization in guinea pig maximization test.

Background : The human patch test is a method used to evaluate potential skin irritation after contact with a cosmetic materials. Pectin lyase-modified red ginseng extract (GS-E3D) is a newly developed ginsenoside Rd-enriched ginseng extract. This study was designed to investigate the skin safety of GS-E3D in human patch test. Methods and Results : Thirty two female volunteers were tested with GS-E3D. GS-E3D (20 ㎕) was applied to occlusive patch test devices and was then applied onto the back of subject with normal skin for 24 hours. Cutaneous irritation responses were evaluated and graded according to criterion of International Contact Dermatitis Research Group (ICDRG) at 30 min, 24 hours, and 48 hours after removing of GS-E3D patch. The average age of subjects was 47.3 ± 9.3 years. Skin reactivity calculated from irritation score in GS-E3D treated group was 0.51 and skin irritation score of no application group was 0, respectively. Skin irritancy was no response in both GS-E3D treated group and no application group. From above data, GS-E3D was identified as a non-irritant according to ICDRG guideline that skin irritation score of ‘0.00 - 0.75’ is a non-irritant. Conclusion : These results indicate that GS-E3D can be useful as a safe cometic ingredient.