The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform
Hassan Zahouani - One of the best experts on this subject based on the ideXlab platform.
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A new approach to describe the Skin Surface physical properties in vivo.
Colloids and surfaces. B Biointerfaces, 2008Co-Authors: C. Pailler-mattei, Sara Nicoli, Fabrice Pirot, R. Vargiolu, Hassan ZahouaniAbstract:Abstract In the present paper, we describe a new mechanical method characterising the physico-chemical properties of human Skin and their variations along with liquid exposure scenario to the Skin Surface. A specific bio-tribometer has been developed to study the physical properties of the Skin in vivo by measuring the maximum adhesion force between the Skin and the bio-tribometer. We showed that the lipidic film present on Skin Surface was responsible for Skin adhesion due to capillary phenomena. The measure of pull-off force between Skin and bio-tribometer has permitted to estimate the liquid/vapour Surface tension of the lipidic film ( γ LV ≈ 6.3 mJ/m 2 in 30-year-old volunteer). The kinetic of sorption/desorption (sorption means indifferently adsorption and absorption process) of distilled water from the Skin has been observed through the variation of the indenter/Skin pull-off force versus time after distilled water application to the Skin Surface. This permits to follow in real time the variation of the Skin physico-chemical properties after liquid application onto the Skin Surface. Finally, the increasing of Skin friction coefficient after distilled water application onto Skin Surface was explained by the capillary adhesion force between the probe and the Skin.
Ron Kohen - One of the best experts on this subject based on the ideXlab platform.
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Skin Surface Proteolytic Activity
Aspartic Proteinases, 1998Co-Authors: Uri Wormser, Berta Brodsky, Eldad Victor Moor, Arie Eldad, Rivka Gal, Abraham Nyska, Ron KohenAbstract:Skin Surface proteolytic activity in the living animal was determined by a sensitive, non-invasive methodology developed in our laboratory. A non-leaky well was constructed on the shaved back of an anesthetized guinea pig. The well contained the reaction mixture including the substrate 125I—S—carboxymethylated insulin B-chain (ICMI). The proteolytic activity was shown to be time-dependent. The activity was strongly inhibited by pepstatin A, indicating the involvement of aspartic proteinase(s) such as cathepsin D and/or E. Pretreatment of the Skin with propylene glycol blocked the proteolytic activity. The present study demonstrates the presence of proteolytic activity located on Skin Surface using a unique, non-invasive method for in situ proteinase determination in the living animal.
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Skin Surface proteolytic activity. Partial characterization and identification.
Advances in experimental medicine and biology, 1998Co-Authors: Uri Wormser, Berta Brodsky, Eldad Victor Moor, Arie Eldad, Abraham Nyska, Gal R, Ron KohenAbstract:Skin Surface proteolytic activity in the living animal was determined by a sensitive, non-invasive methodology developed in our laboratory. A non-leaky well was constructed on the shaved back of an anesthetized guinea pig. The well contained the reaction mixture including the substrate 125I-S-carboxymethylated insulin B-chain (ICMI). The proteolytic activity was shown to be time-dependent. The activity was strongly inhibited by pepstatin A, indicating the involvement of aspartic proteinase(s) such as cathepsin D and/or E. Pretreatment of the Skin with propylene glycol blocked the proteolytic activity. The present study demonstrates the presence of proteolytic activity located on Skin Surface using a unique, non-invasive method for in situ proteinase determination in the living animal.
C. Pailler-mattei - One of the best experts on this subject based on the ideXlab platform.
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A new approach to describe the Skin Surface physical properties in vivo.
Colloids and surfaces. B Biointerfaces, 2008Co-Authors: C. Pailler-mattei, Sara Nicoli, Fabrice Pirot, R. Vargiolu, Hassan ZahouaniAbstract:Abstract In the present paper, we describe a new mechanical method characterising the physico-chemical properties of human Skin and their variations along with liquid exposure scenario to the Skin Surface. A specific bio-tribometer has been developed to study the physical properties of the Skin in vivo by measuring the maximum adhesion force between the Skin and the bio-tribometer. We showed that the lipidic film present on Skin Surface was responsible for Skin adhesion due to capillary phenomena. The measure of pull-off force between Skin and bio-tribometer has permitted to estimate the liquid/vapour Surface tension of the lipidic film ( γ LV ≈ 6.3 mJ/m 2 in 30-year-old volunteer). The kinetic of sorption/desorption (sorption means indifferently adsorption and absorption process) of distilled water from the Skin has been observed through the variation of the indenter/Skin pull-off force versus time after distilled water application to the Skin Surface. This permits to follow in real time the variation of the Skin physico-chemical properties after liquid application onto the Skin Surface. Finally, the increasing of Skin friction coefficient after distilled water application onto Skin Surface was explained by the capillary adhesion force between the probe and the Skin.
Uri Wormser - One of the best experts on this subject based on the ideXlab platform.
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Skin Surface Proteolytic Activity
Aspartic Proteinases, 1998Co-Authors: Uri Wormser, Berta Brodsky, Eldad Victor Moor, Arie Eldad, Rivka Gal, Abraham Nyska, Ron KohenAbstract:Skin Surface proteolytic activity in the living animal was determined by a sensitive, non-invasive methodology developed in our laboratory. A non-leaky well was constructed on the shaved back of an anesthetized guinea pig. The well contained the reaction mixture including the substrate 125I—S—carboxymethylated insulin B-chain (ICMI). The proteolytic activity was shown to be time-dependent. The activity was strongly inhibited by pepstatin A, indicating the involvement of aspartic proteinase(s) such as cathepsin D and/or E. Pretreatment of the Skin with propylene glycol blocked the proteolytic activity. The present study demonstrates the presence of proteolytic activity located on Skin Surface using a unique, non-invasive method for in situ proteinase determination in the living animal.
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Skin Surface proteolytic activity. Partial characterization and identification.
Advances in experimental medicine and biology, 1998Co-Authors: Uri Wormser, Berta Brodsky, Eldad Victor Moor, Arie Eldad, Abraham Nyska, Gal R, Ron KohenAbstract:Skin Surface proteolytic activity in the living animal was determined by a sensitive, non-invasive methodology developed in our laboratory. A non-leaky well was constructed on the shaved back of an anesthetized guinea pig. The well contained the reaction mixture including the substrate 125I-S-carboxymethylated insulin B-chain (ICMI). The proteolytic activity was shown to be time-dependent. The activity was strongly inhibited by pepstatin A, indicating the involvement of aspartic proteinase(s) such as cathepsin D and/or E. Pretreatment of the Skin with propylene glycol blocked the proteolytic activity. The present study demonstrates the presence of proteolytic activity located on Skin Surface using a unique, non-invasive method for in situ proteinase determination in the living animal.
Takao Akama - One of the best experts on this subject based on the ideXlab platform.
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Altered secretory immunoglobulin A on Skin Surface after intensive exercise.
Journal of strength and conditioning research, 2013Co-Authors: Nobuhiko Eda, Kazuhiro Shimizu, Satomi Suzuki, Yoko Tanabe, Eunjae Lee, Takao AkamaAbstract:The aim of this study was to determine the effects of high-intensity endurance exercise on Skin immunity by estimating secretory immunoglobulin A (SIgA) and staphylococci on Skin Surface. Seven healthy adult men (age, 22.3 ± 2.0 years) performed bicycle exercise at 75% HRmax for 60 minutes from 2030 to 2130 hours. Secretory immunoglobulin A was obtained from 1 ml extraction liquids stirred with the microtube homogenizer in the open end of a polypropylene tube for 60 seconds. Secretory immunoglobulin A concentrations were measured using enzyme-linked immunosorbent assay. Staphylococci were harvested by pressed agar-based media against Skin Surface. Skin Surface samples were collected from the chest and the forearm on the first day at 2030 hours (before rest, A1), 2130 hours (after rest, A2), and 2230 hours (after showering, A3); the next morning at 0700 hours (A4); on the second day at 2030 hours (before exercise, B1), 2130 hours (after exercise, B2), and 2230 hours (after showering, B3); and the next morning at 0700 hours (B4). Secretory immunoglobulin A concentration on the forearm was significantly lower at B2 (p < 0.05) and B3 (p < 0.05) than that at B1 and that on the chest at B1 tended to be higher compared with B2 (p = 0.084) and B3 (p = 0.075). The number of staphylococci was significantly higher at B2 than that at B1 (p < 0.01) and B4 (p < 0.01) on the forearm. We conclude that high-intensity endurance exercise might depress immune function and enhance infectious risk on Skin Surface. Coaches should encourage their athletes to take a shower and change into clean clothes immediately after sports activities and athletes should maintain a clean Skin Surface to decrease the infectious risk on Skin Surface.
