• 제목/요약/키워드: Skin concentration

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투과계수를 고려한 의복과 인체 사이의 공기층에서 자연대류 특성 (Natural Convection for Air-Layer between Body Skin and Clothing with Considering Coefficient of Permeability)

  • 지명국;배강렬;정효민;정한식;추미선
    • 설비공학논문집
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    • 제13권12호
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    • pp.1282-1287
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    • 2001
  • This study presents the numerical analysis of natural convection of a micro- environments with air permeability in the clothing air-layer. As a numerical model the clothing air layer of shoulder and arm were adopted. Finite volume method for two-dimensional laminar flow was used for the analysis of flow and thermal characteristics of velocity, temperature and concentration in the air layer between body and clothing. As temperature boundary conditions, a body skin has a high temperature with $34^{\circ}C$ and the environmental temperatures are 5, 15 and $25^{\circ}C$ for various permeability coefficients. The distributions of concentration, temperature and velocity are shown that two large cells form at horizontal and vertical air layer, respectively. As the temperature difference between body skin and environment decreases, the heat transfer is decreased rapidly.

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배 '신고'의 생육기에 나타나는 과피얼룩과의 발생 요인 (Factors Associated with the Occurrence of Fruit Skin Stain during Growing Period in 'Niitaka' Pear)

  • 문병우;남기웅;문영지
    • 한국환경농학회지
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    • 제33권3호
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    • pp.198-204
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    • 2014
  • '신고'배에서 나타나는 과피얼룩과 발생을 경감하기 위하여 생육기 동안 몇 가지를 처리한 결과는 다음과 같다. 배과피얼룩 증상은 유과기(5월 25일)부터 발생하기 시작하여 수확 시까지 나타났으며 과육에는 전혀 발생하지 않았다. 과피얼룩과 발생은 수세가 정상적인 나무, 지베렐린 과경 도포 처리에서 현저하게 낮았으나, 아미노산 수체살포는 큰 차이가 없었다. 봉지에서는 칼슘이 코팅된 봉지 및 석회유황합제가 코팅된 봉지에서 과피얼룩과 발생이 낮았다. 봉지 내지에 석회유황합제 및 콩기름 도포는 과피얼룩이 아닌 약해를 유발시켰다. 과피얼룩 발생과의 수피 및 과피는 K 농도가 높았으나 엽에서는 T-N 및 K 농도는 오히려 낮았다.

피부화상에 의한 피부 및 간의 조직학적 변화에 관한 연구 (A study on Histologically Change of the Skin and Liver in Skin Burn)

  • 김한수;김상수;김용권
    • 대한물리치료과학회지
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    • 제8권1호
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    • pp.923-934
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    • 2001
  • In order to investigate a pathogenesis of liver damage induced by skin burn, thermal injury was induced by scald burn on entirely dorsal surface in rats (total body surface area 30%) except for inhalated injury. At 5 and 24 h after scald bum, biochemical assay and morphological changes in skin tissue, serum and liver tissue were examined. The effects of bum injury on the levels of glutathione, lipid peroxide and on the activities of oxygen free radical generating and scavenging enzymes have been determined in association with observing of histologic and ultrastructural changes, measuring the protein concentration in plasma, and counting the number of intravascular polymorphonuclear leukocytes. The activity of xanthine oxidase, an enzyme of oxygen free radical generating system. was elevated (p<0.01) in serum, but not in skin and in liver tissue. Futhermore, thermal injury decreased not only the protein concentration in plasma but also the number of leukocytes, that indicates induction of edema formation with protein exudation and inflammation by neutrophil infiltration into the internal organs. These data suggest that acute dermal scald burn injury leads to liver damage, that is related to elevation of xanthine oxidase activity in serum. Xanthine oxidase may be a key role in the pathogenesis of liver damage induced by skin burn.

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초음파 병행을 통한 병풀의 미백 및 자외선 차단 활성 증진 효과 (Enhancement of Skin-Whitening and UV-Protective Effects of Centella asiatica L. Urban by Utrasonification Process)

  • 하지혜;권민철;김승섭;정명훈;황백;이현용
    • 한국약용작물학회지
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    • 제18권2호
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    • pp.79-85
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    • 2010
  • Enhancement effect of ultrasonification process on UV-protection and skin-whitening activities using Centella asiatica L. Urban extract was investigated. Cytotoxicity of the extracts measured on human skin fibroblast cells, CCD-986sk, and then, ultrasonification associated extracts showed 5~9% lower cytotoxicity then normal crude extracts on 1.0 mg/$m{\ell}$ of highest sample concentration. The associated extrats showed highest inhibition activity of hyaluronidase on 1.0 mg/$m{\ell}$ of concentration as 54.2%. Also, the associated extract reduced expression of MMP-1 on UV-irradiated CCD-986sk cells down to 100.2% from 136.1%, and revealed high inhibitory potency on tyrosinase as 74.6% by adding 1.0 mg/$m{\ell}$ of concentration. Ultrasonification associated extract showed strong inhibition effect of melanin production on Clone M-3 cells as 84.2% by adding 1.0 mg/$m{\ell}$ of concentration. From the preliminary observations, we considered that the extracts from C. asiatica could be potent natural materials for skin-whitening and anti-aging agent, and could enhance the activities by ultrasonification process.

인삼 알콜 추출물이 개구리 피부를 통한 short circuit current에 미치는 영향 (Effect of Ginseng Alcohol Extract on Short-Circuit Current Across the Frog Skin)

  • 이중우;김희중;강두희
    • The Korean Journal of Physiology
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    • 제10권1호
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    • pp.35-40
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    • 1976
  • In an attempt to examine the effect of ginseng on sodium transport across the biological membrane, we have studied effects of ginseng alcohol extract on the short-circuit current(SCC) and the $Na^+-K^+$-activated ATPase activity in isolated frog skin preparations. 1. Ginseng alcohol extract applied to the mucosal surface of the frog skin significantly increased SCC at low concentration($1{\sim}10mg%$) but decreased SCC at higher concentration($50{\sim}250mg%$). 2. Similarly, when the drug was added to the serosal bathing medium, the SCC was stimulated at low doses($5{\sim}25mg%$) and inhibibited at high doses($50{\sim}250mg%$). 3. $Na^+-K^+$-activated ATPase activity of the frog skin epidermal homogenate was significantly inhibited by ginseng alcohol extract, the effect being proportional to the concentration of the drug in the incubation mixture. These results may suggest that a low dose of ginseng alcohol extrat enhances the transepithelial sodium transport probably by increasing the permeability of outer membrane of the transporting cell to sodium ion, whereas a high dose of drug reduces the sodium transport primarly by inhibiting $Na^+-K^+$ ATPase mediated active transport step.

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급성 피부장벽파괴 동물모델에 대한 스트론튬의 피부보습효과 (Skin Humidity Effects of Strontium on Acute Skin Barrier Damage in Hairless Mice)

  • 민대기;김윤범
    • 대한한의학회지
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    • 제29권1호
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    • pp.117-133
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    • 2008
  • Objectives : Since ancient times, Koreans have applied medicinal spabaths for treatment of various diseases. The objective of this study was to investigate the effect of strontium, one of the common ingredients of such baths, experimentally on acute skin barrier damage. Materials and Methods : Male hairless mice, average weight 20g, were divided into six groups. Each group consisted of five mice. The first was the normal, non-treated group. The second was the control group with acute skin barrier damage intentionally induced by TS. The third was the Ba-Sr1 group bathed in 1mg/L strontium chloride before and after inducing acute skin barrier damage by TS. The fourth was the Ba-Sr7 group bathed in 7mg/L strontium chloride before and after inducing acute skin barrier damage by TS. The fifth was the Sr1 group bathed in 1mg/L of strontium chloride only after intentionally inducing acute skin barrier damage by TS. The sixth was the Sr7 group bathed in 7mg/L of strontium chloride only after intentionally inducing acute skin barrier damage by TS. External changes of skin, skin erythema level, transepidermal water loss level, and GOT and GPT level of each group were checked immediately before and after TS, 3 hrs, 5 hrs and 24 hrs after inducing acute skin barrier damage. Then, tissue samples were made and examined for damage to epithelial cells, stratum corneum, change of mucous polysaccharide in dermis and amount of mast cells. Statistical analysis was performed by one way-ANOVA, Scheffe and Duncan for a post hoc test and pairwise comparison for comparing for difference between each time. Statistical significance was achieved if the probability was less than 5% (p<0.05) Results : 1. From skin erythema and TEWL level indicating the function of the skin barrier, we can know that it is helpful to the skin barrier to bathe in a water solution including a low concentration of strontium. 2. In the control group with acute skin barrier damage induced by TS, skin barrier damage persisted until 3-5 hrs and recovered after 5-24 hrs. Differently from the control group, in the case of taking a bath in a water solution including strontium, skin barrier damage recovered after only 3-5 hrs. Therefore, the bath with a water solution including strontium can promote recovery of the skin barrier. 3. Bathing in water solution including a higher concentration of strontium was more beneficial to recovery of skin barrier damage. 4. There was no influence on serum GOT and GPT from bathing in a water solution including strontium. Conclusions : The strontium was effective for recovery and mitigation of acute skin barrier damage induced by tape stripping. I suggest that strontium (Sr) can be used as an external treatment medicine, addedinto bath water to treat acute skin barrier damage.

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석류농축액의 광노화에 의한 주름 개선 효과 (Effect of pomegranate concentration solution on photoaging)

  • 강수진;최범락;김승희;이해연;박혜림;송창현;박수진;구세광;이영준
    • 대한예방한의학회지
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    • 제19권1호
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    • pp.109-116
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    • 2015
  • Objective : Solar ultraviolet (UV) light can cause photoaging of human skin. Many researchers have focused on effective prevention to mitigate the aging process. This study was aimed to investigate anti-wrinkle effects of pomegranate concentration solution (PCS) using photoaged hairless mouse model. Method : To clarify the protective effect of PCS against UVB-induced photo-damage, water capacity was measured with transepidermal water loss (TEWL) in SKH-1 hairless mice. In addition, image of skin replicas was analyzed. Results : Our results showed that the PCS treatment protects skin against UVB-induced photoaging, based on the parameters including moisture capacity and TEWL. According to visual assessment of skin replica, application of 1 ml/kg PCS inhibited UV-induced wrinkle formation in mice skin as compared to the vehicle-applied control mice. Conclusion : Taken together, these results indicated that PCS could improve skin wrinkle formation induced by UVB irradiation in SHK-1 hairless mice. PCS could be applied as an anti-wrinkle agent.

PREVENTIVE EFFECTS OF RED GINSENG SAPONIN ON HYPERKERATOSIS: ULTRASTRUCTURAL OBSERVATION AND LIPID ANALYSIS

  • Kim, Hyeyoung
    • Toxicological Research
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    • 제7권2호
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    • pp.129-139
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    • 1991
  • Preventive effect of red ginseng saponin on experimentally-induced hyperkeratosis was investigated by ultrastructural observation, skin weight and epidermal lipid analysis. Hexadecane increased skin weight per unit area and epidermal lipids, free fatty acids, cholesterol and triglyceride in guinea pig skin. Topical application of ginseng saponin reduced these hyperkeratotic responses regradless of the concentration and the purity of ginseng saponin. Ultrastructurally, lipids and empty space-containing multiple horny cells were piled and nuclear remnants, desmosome, desmosomal bodies, tight junction were shown in the stratum corneum of hexadecane-treated skin.

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Chitosan-Based Film of Tyrothricin for Enhanced Antimicrobial Activity against Common Skin Pathogens Including Staphylococcus aureus

  • Han, Sang Duk;Sung, Hyun Jung;Lee, Ga Hyeon;Jun, Joon-Ho;Son, Miwon;Kang, Myung Joo
    • Journal of Microbiology and Biotechnology
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    • 제26권5호
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    • pp.953-958
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    • 2016
  • Chitosan-based film-forming gel is regarded as a promising vehicle for topical delivery of antimicrobial agents to skin wounds, since it protects from microbial infection and the cationic polymer itself possesses antibacterial activity. In this study, possible synergistic interaction against common skin pathogens between the cationic polymer and tyrothricin (TRC), a cyclic polypeptide antibiotic, was investigated, by determining the concentration to inhibit 90% of bacterial isolates (MIC). The addition of the polysaccharide to TRC dramatically reduced the MIC values of TRC by 1/33 and 1/4 against both methicillin-resistant and methicillin-susceptible Staphylococcus aureus, respectively. The synergism of TRC and chitosan combination against both strains was demonstrated by the checkerboard method, with a fractional inhibitory concentration index below 0.5. Moreover, co-treatment of TRC and chitosan exhibited antibacterial activity against Pseudomonas aeruginosa, due to the antibacterial activity of chitosan, whereas TRC itself did not inhibit the gram-negative bacterial growth. These findings suggested that the use of chitosan-based film for topical delivery of TRC could be an alternative to improve TRC antimicrobial activity against strains that are abundant in skin wounds.

Acceleration of Wound Healing on Scald Burn Skin Using Irradiation of TDP and Skin Spread of Myrrha

  • Cho Hyun Gug;Kim Keum-Suk;Lee Jong-wook
    • 대한의생명과학회지
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    • 제11권2호
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    • pp.243-248
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    • 2005
  • The present study was conducted to determine whether skin spread of Myrrha and Tending Diancibo Pu (TDP) irradiation have a remarkable effect on the cell regeneration as well as wound healing following dermal scald burn injury. Burn injury was induced on dorsal surface $(TBSA\;15\~20\%)$ by scald burn in rats. Postburn concentration of serum protein was significantly decreased compared with sham-treated, double treatment with Myrrha and TDP was significantly increased the protein concentration compared with that of burn control. The content of keratinocyte growth factor (KGF) at 48 h is higher than that of at 24 h, and double treatment with Myrrha and TDP was the most effective to increase the production of KGF in all experimental groups. Morphologically, epithelial regeneration and dermal collagen synthesis by fibroblasts were accelerated in Myrrha and TDP treated group compared with bum control at same time postburn. At 48 h after burn, all dermal connective tissues are recovered to new collagen fibers in case of Myrrha and TDP double treated group. The data suggest that double treatment with skin spread of Myrrha and TDP radiation have a remarkable effect of to accelerate cell regeneration and wound healing in case of scald burn skin.

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