This comprehensive review explores the multifaceted landscape of skin bioprinting,revolutionizing dermatological research.The applications of skin bioprinting utilizing techniques like extrusion-,droplet-,laser-and li...This comprehensive review explores the multifaceted landscape of skin bioprinting,revolutionizing dermatological research.The applications of skin bioprinting utilizing techniques like extrusion-,droplet-,laser-and light-based methods,with specialized bioinks for skin biofabrication have been critically reviewed along with the intricate aspects of bioprinting hair follicles,sweat glands,and achieving skin pigmentation.Challenges remain with the need for vascularization,safety concerns,and the integration of automated processes for effective clinical translation.The review further investigates the incorporation of biosensor technologies,emphasizing their role in monitoring and enhancing the wound healing process.While highlighting the remarkable progress in the field,critical limitations and concerns are critically examined to provide a balanced perspective.This synthesis aims to guide scientists,engineers,and healthcare providers,fostering a deeper understanding of the current state,challenges,and future directions in skin bioprinting for transformative applications in tissue engineering and regenerative medicine.展开更多
It has been reported that diallyl sulfide (DAS), a sulfur-containing volatile compound in garlic (Allium sativum ), exerts anticarcinogenic activity in various rodent tumor models. In the present study, the antitumor ...It has been reported that diallyl sulfide (DAS), a sulfur-containing volatile compound in garlic (Allium sativum ), exerts anticarcinogenic activity in various rodent tumor models. In the present study, the antitumor property of DAS was tested in Swiss albino mice in the two steqe initiation-promotion mouse skin carcinogenesis. Skin cancers were initiated topically with a single subcarcinOgenic dose (52μg) of 7, 12-dimethyl benz (a) anthracene (DMBA). Promotion was performed by twice weekly applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) at a dose of 5μg/animal for 32 weeks. DAS was applied topically (250μg/animal) thrice weekly for 3 weeks for anti-initiating and 1 h prior to each promotion treatment for anti-promoting studies. The results showed that the treatment schedule of DAS can effectively delay the onset of tumorigenesis and reduce the cumulative number of tumors and the average number of tumors per mouse. In groups in which DAS applied prior to initiation or promotion, a significant population of the aniinals remained tumor-free till the termination of experiment. These findings suggest that DAS can effectively inhibit chemically induced mouse skincarcinogenesis.展开更多
In the present investigations, the antitumorigenic effect of black tea polyphenols (BTP) in twcrstage mouse skin model of carcinogenesis was studied. The animals were initiated with a single 'subcarcinogenic' ...In the present investigations, the antitumorigenic effect of black tea polyphenols (BTP) in twcrstage mouse skin model of carcinogenesis was studied. The animals were initiated with a single 'subcarcinogenic' topical dose (52 μg/200 μl acetone ) of 7, 12-dimethylbenzanthracene (DMBA). To evaluate the anti-tumour initiating activity, BTP was topically applied twice a week for three weeks prior to DMBA application, followed by topical treatment with 12-o-tetradecanoyl phorbol-13-acetate (TPA) (5 μg/200 μl acetone, 2x/wk. ) as promoter. For evaluation of antitumor promoting activity, BTP was applied prior to each treatment of TPA. BTP application showed marked inhibitory effect as antitumour initiator as well as antitumour promoter in mouse skin medel of two-stage carcinogenesis. Since initiation involves genetic pathway and tumour promotion involves epigenetic pathway, it seems that BTP exerts its antitumorigenic effect by altering both genetic and epigenetic pathways展开更多
Skin is the largest organ in human body,and it plays an important role in regulating physiological microenvironments and acts as a barrier to protect human body from harmful intrusions.The demand for fully functional ...Skin is the largest organ in human body,and it plays an important role in regulating physiological microenvironments and acts as a barrier to protect human body from harmful intrusions.The demand for fully functional skin models(also called skin equivalents,SE)in an in-vivo mimicking culturing microenvironment has been increased dramatically due to the fast development in skin disease treatments and skin care products.Owing to the emerging of the concept and technology of organ-on-chips along with the three-dimensional(3D)bioprinting technology,3D skin models and their applications have been fast evolving.In this paper,the advances in the development of 3D skin models along with skin-on-a-chip(SOC)are reviewed and commented.One of the findings with this paper is that the SOC together with the 3D bioprinting technology is promising to construct fully functional 3D skin models in the field of pharmaceutical and cosmetic industries.展开更多
Keratinocytes and fibroblasts,derived from hiPSCs,were used to construct the human epidermal model by a culture patch made by monolayer poly-(lactic-co-glycolic acid)(PLGA)nanofibers and a human skin-on-a-chip device....Keratinocytes and fibroblasts,derived from hiPSCs,were used to construct the human epidermal model by a culture patch made by monolayer poly-(lactic-co-glycolic acid)(PLGA)nanofibers and a human skin-on-a-chip device.Unlike the conventional culture dish method,two different epidermal cells are successfully adhered to the front and back sides of the patch,which produces a three-dimensional nanofibrous scaffold similar to a natural extracellular matrix before the patch was cultured in the skin-on-a-chip device to mimic the physiological conditions of human skin.As expected,the differentiated hiPSCs show the expression of keratinocyte-and fibroblast-specific proteins on the patch,and the layering is found between these two kinds of cells,indicating that this approach creates a powerful in vitro system for modeling skin development and diseases.展开更多
Background: Calotropis procera (C. procera), is an authentic plant naturally grown in the flora of Dead Sea region. Despite its toxicity, C. procera presents healing properties. However, it has not been implemented ye...Background: Calotropis procera (C. procera), is an authentic plant naturally grown in the flora of Dead Sea region. Despite its toxicity, C. procera presents healing properties. However, it has not been implemented yet in cosmetics as an active ingredient. Objective: The biological effects of C. procera callus extract on skin were elucidated solely and in combination with Dead Sea water (DSW). Methods: The capability of C. procera extract to protect against skin inflammation and irritation was tested on ex vivo human skin organ culture by LPS and SDS addition respectively. Viability and cytokine secretion were evaluated. The combination of C. procera extract with Dead Sea water was tested on full thickness skin equivalents. Gene expression and relevant biochemical markers for glycolysis, hypoxia and extracellular matrix balance were tested. Results: C. procera extract exhibits a protective biological activity against skin irritation and inflammation at the biochemical level. Furthermore, a combination of C. procera extract and DSW demonstrates a potential contribution for skin wellbeing via enhance energy production, resistance to hypoxia and extracellular matrix balance. Conclusions: Topical application of C. procera callus extract might support skin balance and wellbeing at the molecular level. Hence, it is recommended for new cosmetic formulae as standalone or in combination with Dead Sea water, in the effort to achieve anti-aging bio-activity that is working beyond skin aging symptoms, especially via skin calming effects and skin energy enhancement.展开更多
An experience is presented using the finite element method （FEM） and data mining （DM） techniques to develop models that can be used to optimieze the skin-pass rolling process based on its operating conditions. A F...An experience is presented using the finite element method （FEM） and data mining （DM） techniques to develop models that can be used to optimieze the skin-pass rolling process based on its operating conditions. A FE model based on a real skin-pass process is built and validated. Based on this model, a group of FE models is simulated with different adjustment parameters and with different materials for the sheet; both variables are chosen from pre-set ranges, From all FE model simulations, a database is generated; this database is made up of the above mentioned adjustment parameters, sheet properties and the variables of the process arising from the simulation of the model. Various types of data mining algorithms are used to develop predictive models for each of the variables of the process.The best predictive models can be used to predict experimentally hard-to-measure variables （internal stresses, internal straine, etc.） which are useful in the optimal design of the process or to be applied in real time control systems of a skin-pass process in -plant.展开更多
Influence of surface topography on the tactile friction of medical compression textiles was studied in this paper. The friction behavior was investigated for three kinds of medical textiles with various structures and...Influence of surface topography on the tactile friction of medical compression textiles was studied in this paper. The friction behavior was investigated for three kinds of medical textiles with various structures and compositions by using a textile friction analyzer under dry condition. In order to simulate the contacts of textiles/human finger, a mechanical skin model with similar texture to the skin and applied normal load oflN were selected. Meanwhile, the 3D surface topography of textiles was measured using a digital microscope. The topographical data were analyzed concerning height distribution and material ratio, and the real contact area was estimated as a function of penetration depth. Results showed that the investigated textiles revealed a significant variation on the friction coefficients, which were （ 0.41 ± 0.01 ） （ polyamide, jersey 2 × 2 ）, （0.56 ± 0. 01） （cotton, jersey 2×2） and （0. 47 ± 0. 01） （polyamide, jersey 1 × 1 ）, respectively. The textile with higher friction coefficient was found to own a relative compact and homogenous surface and larger contact area, vice versa.展开更多
To establish a simple and reliable animal model of skin photo-damage, 20 mice were treated with 8-MOP and exposed to UVA （UVA 320-400 nm） for 24 h. After irradiation, the structure of the epidermis and dermis, colla...To establish a simple and reliable animal model of skin photo-damage, 20 mice were treated with 8-MOP and exposed to UVA （UVA 320-400 nm） for 24 h. After irradiation, the structure of the epidermis and dermis, collagen fibers, elastic fibers were observed by using HE staining and Weigert technique and compared with the normal controls. The acanthosis and epidemis proliferation with accompanying hyperkeratosis and parakeratosis were observed. Inflammatory infiltration was noted in the dermis. The elastic fibers became coarse, irregularly arranged and clustered, with their number increased. The collagen fibers showed obvious degeneration and some amorphous materials could also be observed. The blood vessels were irregularly dilated and vascular walls were thickened, with infiltration of inflammatory cells. It is concluded that murine photodamage model can be quickly, conveniently and reliably established by means of 8-MOP/UVA.展开更多
A 3D nonlinear anisotropic composite biomechanical modeling of human skin was developed according to existing biomechanical experimental results,which can provide insights into the important structure-function relatio...A 3D nonlinear anisotropic composite biomechanical modeling of human skin was developed according to existing biomechanical experimental results,which can provide insights into the important structure-function relationship and parameters in skin tissue.A structural approach determines the macroscopic mechanical response of the skin tissue from its underlying structural components.The collagen fibers were embedded into a block of elastic gel matrix.The constitutive matrix of skin tissue consisted of both of collagen fiber and elastic gel block according to the rule that the collagen fibers were undulated with the ability to resist load only when completely straightened.The nonlinear and anisotropic mechanical responses were largely due to varying degree of fiber undulation.Statistical distributions were used to determine the extent of fiber undulation.The comparison of stress-strain plots between the modeling and experimental results showed the good coordination of the both.Some model parameters were discussed to compute the macroscopic mechanical response when the tissue block was subject to a simple deformation mode.展开更多
Via the use of Mimedisc~? as a scaffold, the normal human dermal fibroblasts were first seeding into the scaffold to form a dermal equivalent after three weeks, and then seeding normal human epidermal keratinocytes on...Via the use of Mimedisc~? as a scaffold, the normal human dermal fibroblasts were first seeding into the scaffold to form a dermal equivalent after three weeks, and then seeding normal human epidermal keratinocytes on it, followed by immersion and air-liquid interphase culture stage, to finally form a 3 D sponge matrix skin model which has a very similar structure of normal human skin(NHS). The results of Masson staining, and immunohistochemistry(IHC), immunofluorescence(IF) staininccg show that this skin model has a very similar structure and key protein expression of NHS. Meanwhile, this model was used as a tool to investigate the effect of Himalaya cedar extract on Dermal-Epidermal Junction(DEJ) in vitro. Results show that the Himalayan cedar extract can significantly increase the thickness of the epidermis, thus increase the barrier capacity of the skin to resist external environment. Further, this Himalaya cedar extract can promote the expressions of Laminin 5 and Collagen VII of DEJ. The expressions of the Laminin 5 and Collagen VII increased 20% and 47% respectively.So the Himalaya cedar extract displays the potential to be applied in development of anti-aging cosmetics.展开更多
A recombinant skin model is a model in which skin cells are grown in vitro on a bioactive scaffold and provided with adequate nutrition to promote cell proliferation and differentiation to produce a mock skin structur...A recombinant skin model is a model in which skin cells are grown in vitro on a bioactive scaffold and provided with adequate nutrition to promote cell proliferation and differentiation to produce a mock skin structure and biological features. The development of recombinant skin models allows for effective and scientifically sound in vitro evaluation tests. This review briefly summarizes the overview of recombinant skin models and the progress of their application in in vitro evaluation which focuses on three aspects: skin irritation, skin corrosivity, and anti-skin aging. Moreover, an outlook on the future development of recombinant skin models is also provided in this review.展开更多
In this work, the suitability of lipid stripping as an alternative model of stratum corneum for plasma medical studies was investigated. Plasma treatment experiments were performed on samples prepared by the cyanoacry...In this work, the suitability of lipid stripping as an alternative model of stratum corneum for plasma medical studies was investigated. Plasma treatment experiments were performed on samples prepared by the cyanoacrylat stripping method. Therefore, two different dielectric barrier discharge-based plasma sources driven by high-voltage pulses in the microsecond and nanosecond range were applied. The lipid sample heating, change in pH-value, and the interaction with plasma-induced UV-radiation are presented and discussed with respect to existing findings on skin samples. After the plasma treatment, the lipid stripping shows similar changes compared to human skin relating to sample heating and pH-value. The investigation of the interplay with UV- radiation shows a high absorption in the wavelength range of 250 nm up to 400 nm. Further, the thickness, surface structure, and composition of lipid stripping samples were determined. The stripped sample shows a thickness of 3 ± 1 μm whereby approximately 30% of the sample surface is covered by lipids. In addition, it was shown that there are no changes in structure caused by the sample preparation. Based on the results of this work, it can be stated that lipid stripping represents an appropriate skin model for plasma medical investigations.展开更多
Skin is the largest organ of the human body. In recent years, concern regarding the cosmetics area has increased, and research studies on anti-aging therapy or cosmetics have been rapidly conducted. Skin cells are not...Skin is the largest organ of the human body. In recent years, concern regarding the cosmetics area has increased, and research studies on anti-aging therapy or cosmetics have been rapidly conducted. Skin cells are not only changing its shape but also its physical properties during the epidermal skin turnover process. Computational simulation can be useful in further understanding the mechanisms of skin formation. We propose a particle model that can handle complex biological phenomena, including cell interactions and is a suitable method for simulating skin formation. The particle model was applied to simulate three-dimensional skin formation accompanied by proliferation and cornification of skin cells. The simulation results represented and reproduced the epidermal skin turnover phenomenon.展开更多
This paper presents finite element models of the fingertip skin which have been created to simulate the contact of textile objects with the skin to gain a better understanding of the perception of textiles through the...This paper presents finite element models of the fingertip skin which have been created to simulate the contact of textile objects with the skin to gain a better understanding of the perception of textiles through the skin, the so-called hand of textiles. Many objective and subjective techniques have already been developed for analysing the hand of textiles;however, none of them provide exact overall information concerning the sensation of textiles through the skin. As the human skin is a complex heterogeneous hyperelastic body composed of many particles, some simplifications had to be made at the early stage of building the models;however, their utilitarian value was maintained. The models relate only to mechanical loading of the skin. They predict a low deformation of the fingertip skin under the pressure of virtual heterogeneous material: acrylic, coarse wool, and steel.展开更多
This paper studied experimentally and theoretically the biomechanical properties of skin with laser influence. Different types of tensile tests of the porcine skin in vitro were conducted to study effect of the laser,...This paper studied experimentally and theoretically the biomechanical properties of skin with laser influence. Different types of tensile tests of the porcine skin in vitro were conducted to study effect of the laser, tensile strength, stress-strain relationship, influence of skin's anisotropy and different regions, repetitive loading and stress-relaxation. A modeling of skin was developed according to the experimental results. The modeling provided insights into the important structure-function relationship in skin tissue with the laser effect. The nonlinear and anisotropic mechanical responses of skin are largely due to varying degree of fiber undulation which is effected by laser and outside forces. By introducing the laser factor into the constitutive modeling, the skin's biomechanical properties and the mechanism of the skin repair with laser were discussed.展开更多
Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis...Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study.展开更多
基金supported by National Institutes of Health Award(Nos.R01DE028614(I T O)and R21AR082668(I T O)),and 2236 CoCirculation2 of TUBITAK award(No.121C359(I T O))supported by The Assistant Secretary of Defense for Health Affairs endorsed by the Department of Defense,in the amount of($1986275)through the Peer Reviewed Medical Research Program under Award Number(No.HT9425-23-1-0487)。
文摘This comprehensive review explores the multifaceted landscape of skin bioprinting,revolutionizing dermatological research.The applications of skin bioprinting utilizing techniques like extrusion-,droplet-,laser-and light-based methods,with specialized bioinks for skin biofabrication have been critically reviewed along with the intricate aspects of bioprinting hair follicles,sweat glands,and achieving skin pigmentation.Challenges remain with the need for vascularization,safety concerns,and the integration of automated processes for effective clinical translation.The review further investigates the incorporation of biosensor technologies,emphasizing their role in monitoring and enhancing the wound healing process.While highlighting the remarkable progress in the field,critical limitations and concerns are critically examined to provide a balanced perspective.This synthesis aims to guide scientists,engineers,and healthcare providers,fostering a deeper understanding of the current state,challenges,and future directions in skin bioprinting for transformative applications in tissue engineering and regenerative medicine.
文摘It has been reported that diallyl sulfide (DAS), a sulfur-containing volatile compound in garlic (Allium sativum ), exerts anticarcinogenic activity in various rodent tumor models. In the present study, the antitumor property of DAS was tested in Swiss albino mice in the two steqe initiation-promotion mouse skin carcinogenesis. Skin cancers were initiated topically with a single subcarcinOgenic dose (52μg) of 7, 12-dimethyl benz (a) anthracene (DMBA). Promotion was performed by twice weekly applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) at a dose of 5μg/animal for 32 weeks. DAS was applied topically (250μg/animal) thrice weekly for 3 weeks for anti-initiating and 1 h prior to each promotion treatment for anti-promoting studies. The results showed that the treatment schedule of DAS can effectively delay the onset of tumorigenesis and reduce the cumulative number of tumors and the average number of tumors per mouse. In groups in which DAS applied prior to initiation or promotion, a significant population of the aniinals remained tumor-free till the termination of experiment. These findings suggest that DAS can effectively inhibit chemically induced mouse skincarcinogenesis.
文摘In the present investigations, the antitumorigenic effect of black tea polyphenols (BTP) in twcrstage mouse skin model of carcinogenesis was studied. The animals were initiated with a single 'subcarcinogenic' topical dose (52 μg/200 μl acetone ) of 7, 12-dimethylbenzanthracene (DMBA). To evaluate the anti-tumour initiating activity, BTP was topically applied twice a week for three weeks prior to DMBA application, followed by topical treatment with 12-o-tetradecanoyl phorbol-13-acetate (TPA) (5 μg/200 μl acetone, 2x/wk. ) as promoter. For evaluation of antitumor promoting activity, BTP was applied prior to each treatment of TPA. BTP application showed marked inhibitory effect as antitumour initiator as well as antitumour promoter in mouse skin medel of two-stage carcinogenesis. Since initiation involves genetic pathway and tumour promotion involves epigenetic pathway, it seems that BTP exerts its antitumorigenic effect by altering both genetic and epigenetic pathways
文摘Skin is the largest organ in human body,and it plays an important role in regulating physiological microenvironments and acts as a barrier to protect human body from harmful intrusions.The demand for fully functional skin models(also called skin equivalents,SE)in an in-vivo mimicking culturing microenvironment has been increased dramatically due to the fast development in skin disease treatments and skin care products.Owing to the emerging of the concept and technology of organ-on-chips along with the three-dimensional(3D)bioprinting technology,3D skin models and their applications have been fast evolving.In this paper,the advances in the development of 3D skin models along with skin-on-a-chip(SOC)are reviewed and commented.One of the findings with this paper is that the SOC together with the 3D bioprinting technology is promising to construct fully functional 3D skin models in the field of pharmaceutical and cosmetic industries.
基金by the National Natural Science Foundation of China(Nos.31600801 and 11804121)the Natural Science Foundation of Hubei(No.2019CFB558)the Central Government Guides the Special Fund Project of Local Scientific and Technological Development(No.[2016]109)。
文摘Keratinocytes and fibroblasts,derived from hiPSCs,were used to construct the human epidermal model by a culture patch made by monolayer poly-(lactic-co-glycolic acid)(PLGA)nanofibers and a human skin-on-a-chip device.Unlike the conventional culture dish method,two different epidermal cells are successfully adhered to the front and back sides of the patch,which produces a three-dimensional nanofibrous scaffold similar to a natural extracellular matrix before the patch was cultured in the skin-on-a-chip device to mimic the physiological conditions of human skin.As expected,the differentiated hiPSCs show the expression of keratinocyte-and fibroblast-specific proteins on the patch,and the layering is found between these two kinds of cells,indicating that this approach creates a powerful in vitro system for modeling skin development and diseases.
文摘Background: Calotropis procera (C. procera), is an authentic plant naturally grown in the flora of Dead Sea region. Despite its toxicity, C. procera presents healing properties. However, it has not been implemented yet in cosmetics as an active ingredient. Objective: The biological effects of C. procera callus extract on skin were elucidated solely and in combination with Dead Sea water (DSW). Methods: The capability of C. procera extract to protect against skin inflammation and irritation was tested on ex vivo human skin organ culture by LPS and SDS addition respectively. Viability and cytokine secretion were evaluated. The combination of C. procera extract with Dead Sea water was tested on full thickness skin equivalents. Gene expression and relevant biochemical markers for glycolysis, hypoxia and extracellular matrix balance were tested. Results: C. procera extract exhibits a protective biological activity against skin irritation and inflammation at the biochemical level. Furthermore, a combination of C. procera extract and DSW demonstrates a potential contribution for skin wellbeing via enhance energy production, resistance to hypoxia and extracellular matrix balance. Conclusions: Topical application of C. procera callus extract might support skin balance and wellbeing at the molecular level. Hence, it is recommended for new cosmetic formulae as standalone or in combination with Dead Sea water, in the effort to achieve anti-aging bio-activity that is working beyond skin aging symptoms, especially via skin calming effects and skin energy enhancement.
基金Item Sponsored by Spanish Ministry of Education and Science(DPI2007-61090)European Commission Research Programme of the Research Fund for Coal and Steel(RFS-PR-06035)
文摘An experience is presented using the finite element method （FEM） and data mining （DM） techniques to develop models that can be used to optimieze the skin-pass rolling process based on its operating conditions. A FE model based on a real skin-pass process is built and validated. Based on this model, a group of FE models is simulated with different adjustment parameters and with different materials for the sheet; both variables are chosen from pre-set ranges, From all FE model simulations, a database is generated; this database is made up of the above mentioned adjustment parameters, sheet properties and the variables of the process arising from the simulation of the model. Various types of data mining algorithms are used to develop predictive models for each of the variables of the process.The best predictive models can be used to predict experimentally hard-to-measure variables （internal stresses, internal straine, etc.） which are useful in the optimal design of the process or to be applied in real time control systems of a skin-pass process in -plant.
基金National Natural Science Foundations of China，Natural Science Foundation of Shanghai,China，the Fundamental Research Funds for the Central Universities,China
文摘Influence of surface topography on the tactile friction of medical compression textiles was studied in this paper. The friction behavior was investigated for three kinds of medical textiles with various structures and compositions by using a textile friction analyzer under dry condition. In order to simulate the contacts of textiles/human finger, a mechanical skin model with similar texture to the skin and applied normal load oflN were selected. Meanwhile, the 3D surface topography of textiles was measured using a digital microscope. The topographical data were analyzed concerning height distribution and material ratio, and the real contact area was estimated as a function of penetration depth. Results showed that the investigated textiles revealed a significant variation on the friction coefficients, which were （ 0.41 ± 0.01 ） （ polyamide, jersey 2 × 2 ）, （0.56 ± 0. 01） （cotton, jersey 2×2） and （0. 47 ± 0. 01） （polyamide, jersey 1 × 1 ）, respectively. The textile with higher friction coefficient was found to own a relative compact and homogenous surface and larger contact area, vice versa.
基金a grant from Hubei Province Natural Science Foundation (No.302131041).
文摘To establish a simple and reliable animal model of skin photo-damage, 20 mice were treated with 8-MOP and exposed to UVA （UVA 320-400 nm） for 24 h. After irradiation, the structure of the epidermis and dermis, collagen fibers, elastic fibers were observed by using HE staining and Weigert technique and compared with the normal controls. The acanthosis and epidemis proliferation with accompanying hyperkeratosis and parakeratosis were observed. Inflammatory infiltration was noted in the dermis. The elastic fibers became coarse, irregularly arranged and clustered, with their number increased. The collagen fibers showed obvious degeneration and some amorphous materials could also be observed. The blood vessels were irregularly dilated and vascular walls were thickened, with infiltration of inflammatory cells. It is concluded that murine photodamage model can be quickly, conveniently and reliably established by means of 8-MOP/UVA.
基金the Innovation Foundation of Shanghai Jiaotong University
文摘A 3D nonlinear anisotropic composite biomechanical modeling of human skin was developed according to existing biomechanical experimental results,which can provide insights into the important structure-function relationship and parameters in skin tissue.A structural approach determines the macroscopic mechanical response of the skin tissue from its underlying structural components.The collagen fibers were embedded into a block of elastic gel matrix.The constitutive matrix of skin tissue consisted of both of collagen fiber and elastic gel block according to the rule that the collagen fibers were undulated with the ability to resist load only when completely straightened.The nonlinear and anisotropic mechanical responses were largely due to varying degree of fiber undulation.Statistical distributions were used to determine the extent of fiber undulation.The comparison of stress-strain plots between the modeling and experimental results showed the good coordination of the both.Some model parameters were discussed to compute the macroscopic mechanical response when the tissue block was subject to a simple deformation mode.
文摘Via the use of Mimedisc~? as a scaffold, the normal human dermal fibroblasts were first seeding into the scaffold to form a dermal equivalent after three weeks, and then seeding normal human epidermal keratinocytes on it, followed by immersion and air-liquid interphase culture stage, to finally form a 3 D sponge matrix skin model which has a very similar structure of normal human skin(NHS). The results of Masson staining, and immunohistochemistry(IHC), immunofluorescence(IF) staininccg show that this skin model has a very similar structure and key protein expression of NHS. Meanwhile, this model was used as a tool to investigate the effect of Himalaya cedar extract on Dermal-Epidermal Junction(DEJ) in vitro. Results show that the Himalayan cedar extract can significantly increase the thickness of the epidermis, thus increase the barrier capacity of the skin to resist external environment. Further, this Himalaya cedar extract can promote the expressions of Laminin 5 and Collagen VII of DEJ. The expressions of the Laminin 5 and Collagen VII increased 20% and 47% respectively.So the Himalaya cedar extract displays the potential to be applied in development of anti-aging cosmetics.
文摘A recombinant skin model is a model in which skin cells are grown in vitro on a bioactive scaffold and provided with adequate nutrition to promote cell proliferation and differentiation to produce a mock skin structure and biological features. The development of recombinant skin models allows for effective and scientifically sound in vitro evaluation tests. This review briefly summarizes the overview of recombinant skin models and the progress of their application in in vitro evaluation which focuses on three aspects: skin irritation, skin corrosivity, and anti-skin aging. Moreover, an outlook on the future development of recombinant skin models is also provided in this review.
基金supported by the European Regional Development Funds(EFRE)and the Workgroup Innovative Projects of Lower Saxony(AGiP)in the frame of the Lower Saxony Innovation Network for Plasma Technology(NIP),project funding reference number W2-80029388.
文摘In this work, the suitability of lipid stripping as an alternative model of stratum corneum for plasma medical studies was investigated. Plasma treatment experiments were performed on samples prepared by the cyanoacrylat stripping method. Therefore, two different dielectric barrier discharge-based plasma sources driven by high-voltage pulses in the microsecond and nanosecond range were applied. The lipid sample heating, change in pH-value, and the interaction with plasma-induced UV-radiation are presented and discussed with respect to existing findings on skin samples. After the plasma treatment, the lipid stripping shows similar changes compared to human skin relating to sample heating and pH-value. The investigation of the interplay with UV- radiation shows a high absorption in the wavelength range of 250 nm up to 400 nm. Further, the thickness, surface structure, and composition of lipid stripping samples were determined. The stripped sample shows a thickness of 3 ± 1 μm whereby approximately 30% of the sample surface is covered by lipids. In addition, it was shown that there are no changes in structure caused by the sample preparation. Based on the results of this work, it can be stated that lipid stripping represents an appropriate skin model for plasma medical investigations.
文摘Skin is the largest organ of the human body. In recent years, concern regarding the cosmetics area has increased, and research studies on anti-aging therapy or cosmetics have been rapidly conducted. Skin cells are not only changing its shape but also its physical properties during the epidermal skin turnover process. Computational simulation can be useful in further understanding the mechanisms of skin formation. We propose a particle model that can handle complex biological phenomena, including cell interactions and is a suitable method for simulating skin formation. The particle model was applied to simulate three-dimensional skin formation accompanied by proliferation and cornification of skin cells. The simulation results represented and reproduced the epidermal skin turnover phenomenon.
文摘This paper presents finite element models of the fingertip skin which have been created to simulate the contact of textile objects with the skin to gain a better understanding of the perception of textiles through the skin, the so-called hand of textiles. Many objective and subjective techniques have already been developed for analysing the hand of textiles;however, none of them provide exact overall information concerning the sensation of textiles through the skin. As the human skin is a complex heterogeneous hyperelastic body composed of many particles, some simplifications had to be made at the early stage of building the models;however, their utilitarian value was maintained. The models relate only to mechanical loading of the skin. They predict a low deformation of the fingertip skin under the pressure of virtual heterogeneous material: acrylic, coarse wool, and steel.
基金the National Natural Science Foundation of China (No. 51178265)
文摘This paper studied experimentally and theoretically the biomechanical properties of skin with laser influence. Different types of tensile tests of the porcine skin in vitro were conducted to study effect of the laser, tensile strength, stress-strain relationship, influence of skin's anisotropy and different regions, repetitive loading and stress-relaxation. A modeling of skin was developed according to the experimental results. The modeling provided insights into the important structure-function relationship in skin tissue with the laser effect. The nonlinear and anisotropic mechanical responses of skin are largely due to varying degree of fiber undulation which is effected by laser and outside forces. By introducing the laser factor into the constitutive modeling, the skin's biomechanical properties and the mechanism of the skin repair with laser were discussed.
文摘Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study.
