Effect of Factor XIII-A G185T Polymorphism on Visual Prognosis after Photodynamic Therapy for Neovascular Macular Degeneration

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Francesco Parmeggiani

2015-08-01

Full Text Available Macular degenerations represent leading causes of central blindness or low vision in developed countries. Most of these severe visual disabilities are due to age-related macular degeneration (AMD and pathologic myopia (PM, both of which are frequently complicated by subfoveal choroidal neovascularization (CNV. Photodynamic therapy with verteporfin (PDT-V is still employed for CNV treatment in selected cases or in combined regimen. In Caucasian patients, the common polymorphism G185T of factor XIII-A gene (FXIII-A-G185T; rs5985 has been described as predictor of poor angiographic CNV responsiveness to PDT-V. Nevertheless, the prognostic implications of this pharmacogenetic determinant on long-term visual outcome after a PDT-V regimen have not been evaluated. We retrospectively selected Caucasian patients presenting with treatment-naive CNV and receiving standardized PDT-V protocol for two years. The study population included patients affected by subfoveal CNV secondary to AMD or PM. We assessed the correlations between the polymorphic allele T of FXIII-A-G185T and: (1 total number of photodynamic treatments; and (2 change in visual acuity from baseline to the end of the follow-up period. Considering a total study population of 412 patients with neovascular AMD or PM, the carriers of 185 T-allele of FXIII-A (GT or TT genotype received a higher number of photodynamic treatments than patients without it (GG wild-type genotype (p < 0.01; mean number of PDT-V: 5.51 vs. 3.76, respectively. Moreover, patients with 185 T-allele of FXIII-A had a more marked worsening of visual acuity at 24 months than those with the GG-185 wild genotype (p < 0.01; mean difference in logMAR visual acuity: 0.22 vs. 0.08, respectively. The present findings show that the G185T polymorphism of the FXIII-A gene is associated with significant differences in the long-term therapeutic outcomes of patients treated with standardized PDT-V protocol. The comprehensive appraisal of

Dextran derivatives modulate collagen matrix organization in dermal equivalent.

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Frank, Laetitia; Lebreton-Decoster, Corinne; Godeau, Gaston; Coulomb, Bernard; Jozefonvicz, Jacqueline

2006-01-01

Dextran derivatives can protect heparin binding growth factor implied in wound healing, such as transforming growth factor-beta1 (TGF-beta1) and fibroblast growth factor-2 (FGF-2). The first aim of this study was to investigate the effect of these compounds on human dermal fibroblasts in culture with or without TGF-beta1. Several dextran derivatives obtained by substitution of methylcarboxylate (MC), benzylamide (B) and sulphate (Su) groups were used to determine the effects of each compound on fibroblast growth in vitro. The data indicate that sulphate groups are essential to act on the fibroblast proliferation. The dextran derivative LS21 DMCBSu has been chosen to investigate its effect on dermal wound healing process. Fibroblasts cultured in collagenous matrices named dermal equivalent were treated with the bioactive polymer alone or associated to TGF-beta1 or FGF-2. Cross-sections of dermal equivalent observed by histology or immunohistochemistry, demonstrated that the bioactive polymer accelerates the collagen matrices organization and stimulates the human type-III collagen expression. This bioactive polymer induces apoptosis of myofibroblast, property which may be beneficial in treatment of hypertrophic scar. Culture media analyzed by zymography and Western blot showed that this polymer significantly increases the secretion of zymogen and active form of matrix metalloproteinase-2 (MMP-2), involved in granulation tissue formation. These data suggest that this bioactive polymer has properties which may be beneficial in the treatment of wound healing.

Validation of the dermal exposure model in ECETOC TRA.

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Marquart, Hans; Franken, Remy; Goede, Henk; Fransman, Wouter; Schinkel, Jody

2017-08-01

factor of 34 in this data set, while factors of five to ten were used in the model estimations. There was also an effect of the sampling method in the measured data on the exposure levels. Exposure cases where sampling was done via an interception method, such as gloves, on average showed a factor of six higher 75th percentiles of measured values than exposure cases where sampling was done via a removal method, such as hand washing. This may partly be responsible for the apparent underestimation of dermal exposure by the model at high exposure values. However, there also appeared to be a relation between expected exposure level (as indicated by the model estimate) and the choice of sampling method.In this study, solid substances used in liquid products were treated as liquids with negligible volatility. The results indicate that the ECETOC TRA dermal exposure model performs equally well for these substances as for liquids. There were suggestions of a difference in performance of the model between solids and liquids.For several parts of the ECETOC TRA dermal model, no or hardly any measured dermal exposure data were available. Therefore, gathering of more dermal exposure levels is recommended, specifically for situations not yet sufficiently covered in the present data set. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Respiratory and dermal symptoms in Thai nurses using latex products.

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Supapvanich, C; Povey, A C; de Vocht, F

2013-09-01

Despite known health risks related to the use of powdered latex gloves (PLGs), they are still widely used in hospitals in developing countries due to the high cost of alternatives. To determine the prevalence of dermal and respiratory symptoms associated with latex glove use in nurses in Thailand and evaluate the influence of previously reported occupational risk factors in this population. A cross-sectional study in female nurses working in three Thai hospitals. Participants completed a questionnaire on demographics, occupational and personal history, use of latex products at work and dermal and respiratory symptoms attributed to occupational use of latex gloves. Of 899 nurses, 18% reported health effects attributed to the use of latex products. After adjustment for confounding, occupational risk factors associated with increased reporting of dermal symptoms included wearing more than 15 pairs of PLG per day (odds ratio (OR): 2.10, 95% confidence interval (CI): [1.32-3.34]), using chlorhexidine (OR: 2.07, 95% CI: [1.22-3.52]) and being an operating theatre nurse (OR: 2.46, 95% CI: [1.47-4.12]). Being a labour ward nurse (OR: 3.52, 95% CI: [1.26-9.85]) was the only factor associated with increased reporting of respiratory symptoms. Continuing use of PLGs in Thai nurses is associated with increased prevalence of dermal symptoms compared with data from developed countries. Measures to reduce such health effects are well established and should be considered. Additionally, replacement of chlorhexidine with an alternative detergent seems advisable.

[Penile augmentation using acellular dermal matrix].

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Zhang, Jin-ming; Cui, Yong-yan; Pan, Shu-juan; Liang, Wei-qiang; Chen, Xiao-xuan

2004-11-01

Penile enhancement was performed using acellular dermal matrix. Multiple layers of acellular dermal matrix were placed underneath the penile skin to enlarge its girth. Since March 2002, penile augmentation has been performed on 12 cases using acellular dermal matrix. Postoperatively all the patients had a 1.3-3.1 cm (2.6 cm in average) increase in penile girth in a flaccid state. The penis had normal appearance and feeling without contour deformities. All patients gained sexual ability 3 months after the operation. One had a delayed wound healing due to tight dressing, which was repaired with a scrotal skin flap. Penile enlargement by implantation of multiple layers of acellular dermal matrix was a safe and effective operation. This method can be performed in an outpatient ambulatory setting. The advantages of the acellular dermal matrix over the autogenous dermal fat grafts are elimination of donor site injury and scar and significant shortening of operation time.

Natural flexible dermal armor.

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Yang, Wen; Chen, Irene H; Gludovatz, Bernd; Zimmermann, Elizabeth A; Ritchie, Robert O; Meyers, Marc A

2013-01-04

Fish, reptiles, and mammals can possess flexible dermal armor for protection. Here we seek to find the means by which Nature derives its protection by examining the scales from several fish (Atractosteus spatula, Arapaima gigas, Polypterus senegalus, Morone saxatilis, Cyprinius carpio), and osteoderms from armadillos, alligators, and leatherback turtles. Dermal armor has clearly been developed by convergent evolution in these different species. In general, it has a hierarchical structure with collagen fibers joining more rigid units (scales or osteoderms), thereby increasing flexibility without significantly sacrificing strength, in contrast to rigid monolithic mineral composites. These dermal structures are also multifunctional, with hydrodynamic drag (in fish), coloration for camouflage or intraspecies recognition, temperature and fluid regulation being other important functions. The understanding of such flexible dermal armor is important as it may provide a basis for new synthetic, yet bioinspired, armor materials. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Focal dermal hypoplasia without focal dermal hypoplasia

NARCIS (Netherlands)

Contreras-Capetillo, Silvina N.; Lombardi, Maria Paola; Pinto-Escalante, Doris; Hennekam, Raoul C.

2014-01-01

Focal dermal hypoplasia (FDH; Goltz-Gorlin syndrome) is an X-linked dominant disorder affecting mainly tissues of ectodermal and mesodermal origin. The phenotype is characterized by hypoplastic linear skin lesions, eye malformations, hair and teeth anomalies, and multiple limbs malformations. The

Biological background of dermal substitutes

NARCIS (Netherlands)

van der Veen, V. C.; van der Wal, M.B.; van Leeuwen, M.C.; Ulrich, M.; Middelkoop, E.

2010-01-01

Dermal substitutes are of major importance in treating full thickness skin defects, both in acute and chronic wounds. In this review we will outline specific requirements of three classes of dermal substitutes:-natural biological materials, with a more or less intact extracellular matrix

Use of Porcine Acellular Dermal Matrix as a Dermal Substitute in Rats

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Srivastava, Anil; DeSagun, Evangeline Z.; Jennings, Lawrence J.; Sethi, Stephen; Phuangsab, Anan; Hanumadass, Marella; Reyes, Hernan M.; Walter, Robert J.

2001-01-01

Objective To examine porcine acellular dermal matrix (ADM) as a xenogenic dermal substitute in a rat model. Summary Background Data Acellular dermal matrix has been used in the treatment of full-thickness skin injuries as an allogenic dermal substitute providing a stable wound base in human and animal studies. Methods Xenogenic and allogenic ADMs were produced by treating porcine or rat skin with Dispase and Triton X-100. Full-thickness skin defects (225 mm2) were created on the dorsum of rats (n = 29), porcine or rat ADMs were implanted in them, and these were overlain with ultrathin split-thickness skin grafts (STSGs). In two adjacent wounds, 0.005- or 0.017-inch-thick autografts were implanted. In other experiments, the antimicrobial agent used during ADM processing (azide or a mixture of antibiotics) and the orientation of the implanted ADM (papillary or reticular side of ADM facing the STSG) were studied. Grafts were evaluated grossly and histologically for 30 days after surgery. Results Significant wound contraction was seen at 14, 20, and 30 days after surgery in wounds receiving xenogenic ADM, allogenic ADM, and thin STSGs. Contraction of wounds containing xenogenic ADM was significantly greater than that of wounds containing allogenic ADM at 30 days after surgery. Graft take was poor in wounds containing xenogenic ADM and moderately good in those containing allogenic ADM. Wound healing was not significantly affected by the antimicrobial agent used during ADM preparation or by the ADM orientation. Conclusion Dispase–Triton-treated allogenic ADM was useful as a dermal substitute in full-thickness skin defects, but healing with xenogenic ADM was poor. PMID:11224629

A review of critical factors for assessing the dermal absorption of metal oxide nanoparticles from sunscreens applied to humans, and a research strategy to address current deficiencies.

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Gulson, Brian; McCall, Maxine J; Bowman, Diana M; Pinheiro, Teresa

2015-11-01

Metal oxide nanoparticles in sunscreens provide broad-spectrum ultraviolet protection to skin. All studies to assess dermal penetration of nanoparticles have unanimously concluded that the overwhelming majority of nanoparticles remain on the outer surface of the skin. However, possibly due to many different experimental protocols in use, conclusions over the potential penetration to viable skin are mixed. Here, we review several factors that may influence experimental results for dermal penetration including the species studied (human, or animal model), size and coating of the metal oxide nanoparticles, composition of the sunscreen formulation, site of sunscreen application, dose and number of applications, duration of the study, types of biological samples analysed, methods for analysing samples, exposure to UV and skin flexing. Based on this information, we suggest an appropriate research agenda involving international collaboration that maximises the potential for dermal absorption of nanoparticles, and their detection, under normal conditions of sunscreen use by humans. If results from this research agenda indicate no absorption is observed, then concerns over adverse health effects from the dermal absorption of nanoparticles in sunscreens may be allayed.

Inductive capacity of irradiated dermal papillae

International Nuclear Information System (INIS)

Ibrahim, L.; Wright, E.A.

1977-01-01

It is stated that the importance of the dermal papilla for the maintenance and control of hair cycles in mammals has long been recognised, but there has been little direct evidence of its mode of functioning. Permanent removal of rat body hair has resulted from large doses of X-radiation and it was believed that this caused destruction of the dermal papilla, which in turn resulted in permanent epilation. A study is here reported on the effect of heavy doses of irradiation on the dermal papilla and epithelial elements of the hair follicles of mice and rats. It was found that the high doses that caused permanent epilation destroyed the epithelium but left the dermal papilla anatomically and functionally intact, so that even on transplantation it could induce a series of new hairs. The dose employed was 2500 R of X-radiation for mice or 5000 R for rats. Hairs after transplantation were shorter than normal and had a slower rate of growth; depending on the size of the transplanted dermal papilla. The hairs become shorter with successive cycles of irradiation. (U.K.)

Interleukin-1β attenuates myofibroblast formation and extracellular matrix production in dermal and lung fibroblasts exposed to transforming growth factor-β1.

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Masum M Mia

Full Text Available One of the most potent pro-fibrotic cytokines is transforming growth factor (TGFβ. TGFβ is involved in the activation of fibroblasts into myofibroblasts, resulting in the hallmark of fibrosis: the pathological accumulation of collagen. Interleukin-1β (IL1β can influence the severity of fibrosis, however much less is known about the direct effects on fibroblasts. Using lung and dermal fibroblasts, we have investigated the effects of IL1β, TGFβ1, and IL1β in combination with TGFβ1 on myofibroblast formation, collagen synthesis and collagen modification (including prolyl hydroxylase, lysyl hydroxylase and lysyl oxidase, and matrix metalloproteinases (MMPs. We found that IL1β alone has no obvious pro-fibrotic effect on fibroblasts. However, IL1β is able to inhibit the TGFβ1-induced myofibroblast formation as well as collagen synthesis. Glioma-associated oncogene homolog 1 (GLI1, the Hedgehog transcription factor that is involved in the transformation of fibroblasts into myofibroblasts is upregulated by TGFβ1. The addition of IL1β reduced the expression of GLI1 and thereby also indirectly inhibits myofibroblast formation. Other potentially anti-fibrotic effects of IL1β that were observed are the increased levels of MMP1, -2, -9 and -14 produced by fibroblasts exposed to TGFβ1/IL1β in comparison with fibroblasts exposed to TGFβ1 alone. In addition, IL1β decreased the TGFβ1-induced upregulation of lysyl oxidase, an enzyme involved in collagen cross-linking. Furthermore, we found that lung and dermal fibroblasts do not always behave identically towards IL1β. Suppression of COL1A1 by IL1β in the presence of TGFβ1 is more pronounced in lung fibroblasts compared to dermal fibroblasts, whereas a higher upregulation of MMP1 is seen in dermal fibroblasts. The role of IL1β in fibrosis should be reconsidered, and the differences in phenotypical properties of fibroblasts derived from different organs should be taken into account in future

Clotting of mammalian fibrinogens by papain: a re-examination.

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Doolittle, Russell F

2014-10-28

Papain has long been known to cause the gelation of mammalian fibrinogens. It has also been reported that papain-fibrin is insoluble in dispersing solvents like strong urea or sodium bromide solutions, similar to what is observed with thrombin-generated clots in the presence of factor XIIIa and calcium. In those old studies, both the gelation and subsequent clot stabilization were attributed to papain, although the possibility that the second step might be due to contaminating factor XIII in fibrinogen preparations was considered. I have revisited this problem in light of knowledge acquired over the past half-century about thiol proteases like papain, which mostly cleave peptide bonds, and transglutaminases like factor XIIIa that catalyze the formation of ε-lysyl-γ-glutamyl cross-links. Recombinant fibrinogen, inherently free of factor XIII and other plasma proteins, formed a stable gel when treated with papain alone. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the intermolecular cross-linking in papain-fibrin leads to γ-chain dimers, trimers, and tetramers, just as is the case with thrombin-factor XIIIa-stabilized fibrin. Mass spectrometry of bands excised from gels showed that the cross-linked material is quite different from what occurs with factor XIIIa, however. With papain, the cross-linking occurs between γ chains in neighboring protofibrils becoming covalently linked in a "head-to-tail" fashion by a transpeptidation reaction involving the α-amino group of γ-Tyr1 and a papain cleavage site at γ-Gly403 near the carboxy terminus, rather than by the (reciprocal) "tail-to-tail" manner that occurs with factor XIIIa and that depends on cross-links between γ-Lys406 and γ-Gln398.

Thermoreversible gelation polymer as an embolic material for aneurysm treatment: a delivery device for dermal fibroblasts and basic fibroblast growing factor into experimental aneurysms in rats.

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Dobashi, Hisashi; Akasaki, Yasuharu; Yuki, Ichiro; Arai, Takao; Ohashi, Hiroki; Murayama, Yuichi; Takao, Hiroyuki; Abe, Toshiaki

2013-11-01

This study evaluates whether thermoreversible gelation polymer (TGP) can be used as a delivery device to deploy dermal fibroblasts and cytokines into experimental aneurysms in rats. The right common iliac artery of rats was surgically ligated and an experimental aneurysm was created by applying exogenous elastase. Seven days later, two aneurysms were harvested and used as controls (Group A), two were embolized with pure TGP (Group B), two were embolized with TGP and basic fibroblast growth factor (bFGF) (Group C) and two were embolized with TGP loaded with rat dermal fibroblasts (Group D). The aneurysms were also embolized with TGP mixed with dermal fibroblasts and bFGF at different concentrations (10 ng/ml: Group E (n=2), 100 ng/ml: Group F (n=2), 1000 ng/ml: Group G (n=2)). Each aneurysm sample was harvested after 7 days and histologic analyses were performed. The most advanced thrombus organization in the aneurysm, such as prominent fibroblast proliferation and collagen deposition, was observed in Groups E, F and G, although there was no noticeable difference between the groups. Moderate thrombus organization was seen in Group D and minimal thrombus organization was seen in Groups B and C. TGP mixed with both dermal fibroblasts and bFGF induced the most advanced thrombus organization in the experimental aneurysms followed by TGP mixed only with dermal fibroblasts. TGP may be useful as a delivery device to deploy fibroblasts and cytokines into aneurysms.

Genetics Home Reference: focal dermal hypoplasia

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... in people with focal dermal hypoplasia is an omphalocele , which is an opening in the wall of ... Dermal Hypoplasia MedlinePlus Encyclopedia: Ectodermal dysplasia MedlinePlus Encyclopedia: Omphalocele General Information from MedlinePlus (5 links) Diagnostic Tests ...

From dermal exposure to internal dose

NARCIS (Netherlands)

Sandt, J.J.M. van de; Dellarco, M.; Hemmen, J.J. van

2007-01-01

Exposure scenarios form an essential basis for chemical risk assessment reports under the new EU chemicals regulation REACH (Registration, Evaluation, Authorisation and restriction of Chemicals). In case the dermal route of exposure is predominant, information on both exposure and dermal

Increased expression of heat shock protein 70 and heat shock factor 1 in chronic dermal ulcer tissues treated with laser-aided therapy.

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Zhou, Jian-da; Luo, Cheng-qun; Xie, Hui-qing; Nie, Xin-min; Zhao, Yan-zhong; Wang, Shao-hua; Xu, Yi; Pokharel, Pashupati Babu; Xu, Dan

2008-07-20

Chronic dermal ulcers are also referred to as refractory ulcers. This study was conducted to elucidate the therapeutic effect of laser on chronic dermal ulcers and the induced expression of heat shock factor 1 (HSF1) and heat shock protein 70 (HSP70) in wound tissues. Sixty patients with 84 chronic dermal ulcers were randomly divided into traditional therapy and laser therapy groups. Laser treatment was performed in addition to traditional therapy in the laser therapy group. The treatment efficacy was evaluated after three weeks. Five tissue sections of healing wounds were randomly collected along with five normal skin sections as controls. HSP70-positive cells from HSP70 immunohistochemical staining were counted and the gray scale of positive cells was measured for statistical analysis. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were performed to determine the mRNA and protein expressions of HSF1 and HSP70. The cure rate of the wounds and the total efficacy in the laser therapy group were significantly higher than those in the traditional therapy group (P ulcers plays a facilitating role in healing due to the mechanism of laser-activated endogenous heat shock protection in cells in wound surfaces.

Plasma Rich in Growth Factors Inhibits Ultraviolet B Induced Photoageing of the Skin in Human Dermal Fibroblast Culture.

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Anitua, Eduardo; Pino, Ander; Orive, Gorka

Ultraviolet irradiation is able to deeply penetrate into the dermis and alter fibroblast structure and function, leading to a degradation of the dermal extracellular matrix. The regenerative effect of plasma rich in growth factors (PRGF) on skin ageing was investigated using UVB photo-stressed human dermal fibroblasts as an in vitro culture model. PRGF was assessed over the main indicative features of ultraviolet B irradiation, including ROS formation, cell viability and death detection, apoptosis/ necrosis analysis and biosynthetic activity measurement. Four different UV irradiation protocols were tested in order to analyze the beneficial effects of PRGF. Ultraviolet irradiation exhibited a dose dependent cytotoxicity and dose of 400mJ/cm2 was selected for subsequent experiments. PRGF increased the cell viability and decreased the cell death comparing to the non-treated group. The apoptosis and necrosis were significantly lower in PRGF treated fibroblasts. ROS production after UV irradiation was significantly reduced in the presence of PRGF. Procollagen type I, hyaluronic acid and TIMP-1 levels were higher in the when treated with PRGF. This preliminary in vitro study suggests that PRGF is able to prevent UVB derived photooxidative stress and to diminish the cell damage caused by ultraviolet irradiation.

Dermal uptake of petroleum substances.

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Jakasa, Ivone; Kezic, Sanja; Boogaard, Peter J

2015-06-01

Petroleum products are complex substances comprising varying amounts of linear and branched alkanes, alkenes, cycloalkanes, and aromatics which may penetrate the skin at different rates. For proper interpretation of toxic hazard data, understanding their percutaneous absorption is of paramount importance. The extent and significance of dermal absorption of eight petroleum substances, representing different classes of hydrocarbons, was evaluated. Literature data on the steady-state flux and permeability coefficient of these substances were evaluated and compared to those predicted by mathematical models. Reported results spanned over 5-6 orders of magnitude and were largely dependent on experimental conditions in particular on the type of the vehicle used. In general, aromatic hydrocarbons showed higher dermal absorption than more lipophilic aliphatics with similar molecular weight. The results showed high variation and were largely influenced by experimental conditions emphasizing the need of performing the experiments under "in use" scenario. The predictive models overestimated experimental absorption. The overall conclusion is that, based on the observed percutaneous penetration data, dermal exposure to petroleum hydrocarbons, even of aromatics with highest dermal absorption is limited and highly unlikely to be associated with health risks under real use scenarios. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A two-compartment mechanochemical model of the roles of transforming growth factor and tissue tension in dermal wound healing

KAUST Repository

Murphy, Kelly E.

2011-03-01

The repair of dermal tissue is a complex process of interconnected phenomena, where cellular, chemical and mechanical aspects all play a role, both in an autocrine and in a paracrine fashion. Recent experimental results have shown that transforming growth factor -β (TGF β) and tissue mechanics play roles in regulating cell proliferation, differentiation and the production of extracellular materials. We have developed a 1D mathematical model that considers the interaction between the cellular, chemical and mechanical phenomena, allowing the combination of TGF β and tissue stress to inform the activation of fibroblasts to myofibroblasts. Additionally, our model incorporates the observed feature of residual stress by considering the changing zero-stress state in the formulation for effective strain. Using this model, we predict that the continued presence of TGF β in dermal wounds will produce contractures due to the persistence of myofibroblasts; in contrast, early elimination of TGF β significantly reduces the myofibroblast numbers resulting in an increase in wound size. Similar results were obtained by varying the rate at which fibroblasts differentiate to myofibroblasts and by changing the myofibroblast apoptotic rate. Taken together, the implication is that elevated levels of myofibroblasts is the key factor behind wounds healing with excessive contraction, suggesting that clinical strategies which aim to reduce the myofibroblast density may reduce the appearance of contractures. © 2010 Elsevier Ltd.

A two-compartment mechanochemical model of the roles of transforming growth factor and tissue tension in dermal wound healing

KAUST Repository

Murphy, Kelly E.; Hall, Cameron L.; McCue, Scott W.; Sean McElwain, D.L.

2011-01-01

The repair of dermal tissue is a complex process of interconnected phenomena, where cellular, chemical and mechanical aspects all play a role, both in an autocrine and in a paracrine fashion. Recent experimental results have shown that transforming growth factor -β (TGF β) and tissue mechanics play roles in regulating cell proliferation, differentiation and the production of extracellular materials. We have developed a 1D mathematical model that considers the interaction between the cellular, chemical and mechanical phenomena, allowing the combination of TGF β and tissue stress to inform the activation of fibroblasts to myofibroblasts. Additionally, our model incorporates the observed feature of residual stress by considering the changing zero-stress state in the formulation for effective strain. Using this model, we predict that the continued presence of TGF β in dermal wounds will produce contractures due to the persistence of myofibroblasts; in contrast, early elimination of TGF β significantly reduces the myofibroblast numbers resulting in an increase in wound size. Similar results were obtained by varying the rate at which fibroblasts differentiate to myofibroblasts and by changing the myofibroblast apoptotic rate. Taken together, the implication is that elevated levels of myofibroblasts is the key factor behind wounds healing with excessive contraction, suggesting that clinical strategies which aim to reduce the myofibroblast density may reduce the appearance of contractures. © 2010 Elsevier Ltd.

Primary cell culture and morphological characterization of canine dermal papilla cells and dermal fibroblasts.

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Bratka-Robia, Christine B; Mitteregger, Gerda; Aichinger, Amanda; Egerbacher, Monika; Helmreich, Magdalena; Bamberg, Elmar

2002-02-01

Skin biopsies were taken from female dogs, the primary hair follicles isolated and the dermal papilla dissected. After incubation in supplemented Amniomax complete C100 medium in 24-well culture plates, the dermal papilla cells (DPC) grew to confluence within 3 weeks. Thereafter, they were subcultivated every 7 days. Dermal fibroblast (DFB) cultures were established by explant culture of interfollicular dermis in serum-free medium, where they reached confluence in 10 days. They were subcultivated every 5 days. For immunohistochemistry, cells were grown on cover slips for 24 h, fixed and stained with antibodies against collagen IV and laminin. DPC showed an aggregative growth pattern and formation of pseudopapillae. Intensive staining for collagen IV and laminin could be observed until the sixth passage. DFB grew as branching, parallel lines and showed only weak staining for collagen IV and laminin.

Dermal extracellular lipid in birds.

Science.gov (United States)

Stromberg, M W; Hinsman, E J; Hullinger, R L

1990-01-01

A light and electron microscopic study of the skin of domestic chickens, seagulls, and antarctic penguins revealed abundant extracellular dermal lipid and intracellular epidermal lipid. Dermal lipid appeared ultrastructurally as extracellular droplets varying from less than 1 micron to more than 25 microns in diameter. The droplets were often irregularly contoured, sometimes round, and of relatively low electron density. Processes of fibrocytes were often seen in contact with extracellular lipid droplets. Sometimes a portion of such a droplet was missing, and this missing part appeared to have been "digested away" by the cell process. In places where cells or cell processes are in contact with fact droplets, there are sometimes extracellular membranous whorls or fragments which have been associated with the presence of fatty acids. Occasionally (in the comb) free fat particles were seen in intimate contact with extravasated erythrocytes. Fat droplets were seen in the lumen of small dermal blood and lymph vessels. We suggest that the dermal extracellular lipid originates in the adipocyte layer and following hydrolysis the free fatty acids diffuse into the epidermis. Here they become the raw material for forming the abundant neutral lipid contained in many of the epidermal cells of both birds and dolphins. The heretofore unreported presence and apparently normal utilization of abundant extracellular lipid in birds, as well as the presence of relatively large droplets of neutral lipid in dermal vessels, pose questions which require a thorough reappraisal of present concepts of the ways in which fat is distributed and utilized in the body.

Collagen/chitosan based two-compartment and bi-functional dermal scaffolds for skin regeneration

Energy Technology Data Exchange (ETDEWEB)

Wang, Feng [Department of Plastic Surgery and Burns, Shenzhen Second People' s Hospital, Shenzhen 518035 (China); Wang, Mingbo [Key Laboratory of Biomedical Materials and Implants, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); She, Zhending [Key Laboratory of Biomedical Materials and Implants, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); Shenzhen Lando Biomaterials Co., Ltd., Shenzhen 518057 (China); Fan, Kunwu; Xu, Cheng [Department of Plastic Surgery and Burns, Shenzhen Second People' s Hospital, Shenzhen 518035 (China); Chu, Bin; Chen, Changsheng [Key Laboratory of Biomedical Materials and Implants, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); Shi, Shengjun, E-mail: shengjunshi@yahoo.com [The Burns Department of Zhujiang Hospital, Southern Medical University, Guangzhou 510280 (China); Tan, Rongwei, E-mail: tanrw@landobiom.com [Key Laboratory of Biomedical Materials and Implants, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); Shenzhen Lando Biomaterials Co., Ltd., Shenzhen 518057 (China)

2015-07-01

Inspired from the sophisticated bilayer structures of natural dermis, here, we reported collagen/chitosan based two-compartment and bi-functional dermal scaffolds. Two functions refer to mediating rapid angiogenesis based on recombinant human vascular endothelial growth factor (rhVEGF) and antibacterial from gentamicin, which were encapsulated in PLGA microspheres. The gentamicin and rhVEGF encapsulated PLGA microspheres were further combined with collagen/chitosan mixtures in low (lower layer) and high (upper layer) concentrations, and molded to generate the two-compartment and bi-functional scaffolds. Based on morphology and pore structure analyses, it was found that the scaffold has a distinct double layered porous and connective structure with PLGA microspheres encapsulated. Statistical analysis indicated that the pores in the upper layer and in the lower layer have great variations in diameter, indicative of a two-compartment structure. The release profiles of gentamicin and rhVEGF exceeded 28 and 49 days, respectively. In vitro culture of mouse fibroblasts showed that the scaffold can facilitate cell adhesion and proliferation. Moreover, the scaffold can obviously inhibit proliferation of Staphylococcus aureus and Serratia marcescens, exhibiting its unique antibacterial effect. The two-compartment and bi-functional dermal scaffolds can be a promising candidate for skin regeneration. - Highlights: • The dermal scaffold is inspired from the bilayer structures of natural dermis. • The dermal scaffold has two-compartment structures. • The dermal scaffold containing VEGF and gentamicin encapsulated PLGA microspheres • The dermal scaffold can facilitate cell adhesion and proliferation.

Collagen/chitosan based two-compartment and bi-functional dermal scaffolds for skin regeneration

International Nuclear Information System (INIS)

Wang, Feng; Wang, Mingbo; She, Zhending; Fan, Kunwu; Xu, Cheng; Chu, Bin; Chen, Changsheng; Shi, Shengjun; Tan, Rongwei

2015-01-01

Inspired from the sophisticated bilayer structures of natural dermis, here, we reported collagen/chitosan based two-compartment and bi-functional dermal scaffolds. Two functions refer to mediating rapid angiogenesis based on recombinant human vascular endothelial growth factor (rhVEGF) and antibacterial from gentamicin, which were encapsulated in PLGA microspheres. The gentamicin and rhVEGF encapsulated PLGA microspheres were further combined with collagen/chitosan mixtures in low (lower layer) and high (upper layer) concentrations, and molded to generate the two-compartment and bi-functional scaffolds. Based on morphology and pore structure analyses, it was found that the scaffold has a distinct double layered porous and connective structure with PLGA microspheres encapsulated. Statistical analysis indicated that the pores in the upper layer and in the lower layer have great variations in diameter, indicative of a two-compartment structure. The release profiles of gentamicin and rhVEGF exceeded 28 and 49 days, respectively. In vitro culture of mouse fibroblasts showed that the scaffold can facilitate cell adhesion and proliferation. Moreover, the scaffold can obviously inhibit proliferation of Staphylococcus aureus and Serratia marcescens, exhibiting its unique antibacterial effect. The two-compartment and bi-functional dermal scaffolds can be a promising candidate for skin regeneration. - Highlights: • The dermal scaffold is inspired from the bilayer structures of natural dermis. • The dermal scaffold has two-compartment structures. • The dermal scaffold containing VEGF and gentamicin encapsulated PLGA microspheres • The dermal scaffold can facilitate cell adhesion and proliferation

Mesenchymal stem cells induce dermal fibroblast responses to injury

International Nuclear Information System (INIS)

Smith, Andria N.; Willis, Elise; Chan, Vincent T.; Muffley, Lara A.; Isik, F. Frank; Gibran, Nicole S.; Hocking, Anne M.

2010-01-01

Although bone marrow-derived mesenchymal stem cells have been shown to promote repair when applied to cutaneous wounds, the mechanism for this response remains to be determined. The aim of this study was to determine the effects of paracrine signaling from mesenchymal stem cells on dermal fibroblast responses to injury including proliferation, migration and expression of genes important in wound repair. Dermal fibroblasts were co-cultured with bone marrow-derived mesenchymal stem cells grown in inserts, which allowed for paracrine interactions without direct cell contact. In this co-culture model, bone marrow-derived mesenchymal stem cells regulate dermal fibroblast proliferation, migration and gene expression. When co-cultured with mesenchymal stem cells, dermal fibroblasts show increased proliferation and accelerated migration in a scratch assay. A chemotaxis assay also demonstrated that dermal fibroblasts migrate towards bone marrow-derived mesenchymal stem cells. A PCR array was used to analyze the effect of mesenchymal stem cells on dermal fibroblast gene expression. In response to mesenchymal stem cells, dermal fibroblasts up-regulate integrin alpha 7 expression and down-regulate expression of ICAM1, VCAM1 and MMP11. These observations suggest that mesenchymal stem cells may provide an important early signal for dermal fibroblast responses to cutaneous injury.

Task-based dermal exposure models for regulatory risk assessment.

Science.gov (United States)

Warren, Nicholas D; Marquart, Hans; Christopher, Yvette; Laitinen, Juha; VAN Hemmen, Joop J

2006-07-01

The regulatory risk assessment of chemicals requires the estimation of occupational dermal exposure. Until recently, the models used were either based on limited data or were specific to a particular class of chemical or application. The EU project RISKOFDERM has gathered a considerable number of new measurements of dermal exposure together with detailed contextual information. This article describes the development of a set of generic task-based models capable of predicting potential dermal exposure to both solids and liquids in a wide range of situations. To facilitate modelling of the wide variety of dermal exposure situations six separate models were made for groupings of exposure scenarios called Dermal Exposure Operation units (DEO units). These task-based groupings cluster exposure scenarios with regard to the expected routes of dermal exposure and the expected influence of exposure determinants. Within these groupings linear mixed effect models were used to estimate the influence of various exposure determinants and to estimate components of variance. The models predict median potential dermal exposure rates for the hands and the rest of the body from the values of relevant exposure determinants. These rates are expressed as mg or microl product per minute. Using these median potential dermal exposure rates and an accompanying geometric standard deviation allows a range of exposure percentiles to be calculated.

A two-compartment mechanochemical model of the roles of transforming growth factor β and tissue tension in dermal wound healing.

Science.gov (United States)

Murphy, Kelly E; Hall, Cameron L; McCue, Scott W; Sean McElwain, D L

2011-03-07

The repair of dermal tissue is a complex process of interconnected phenomena, where cellular, chemical and mechanical aspects all play a role, both in an autocrine and in a paracrine fashion. Recent experimental results have shown that transforming growth factor -β (TGFβ) and tissue mechanics play roles in regulating cell proliferation, differentiation and the production of extracellular materials. We have developed a 1D mathematical model that considers the interaction between the cellular, chemical and mechanical phenomena, allowing the combination of TGFβ and tissue stress to inform the activation of fibroblasts to myofibroblasts. Additionally, our model incorporates the observed feature of residual stress by considering the changing zero-stress state in the formulation for effective strain. Using this model, we predict that the continued presence of TGFβ in dermal wounds will produce contractures due to the persistence of myofibroblasts; in contrast, early elimination of TGFβ significantly reduces the myofibroblast numbers resulting in an increase in wound size. Similar results were obtained by varying the rate at which fibroblasts differentiate to myofibroblasts and by changing the myofibroblast apoptotic rate. Taken together, the implication is that elevated levels of myofibroblasts is the key factor behind wounds healing with excessive contraction, suggesting that clinical strategies which aim to reduce the myofibroblast density may reduce the appearance of contractures. Copyright © 2010 Elsevier Ltd. All rights reserved.

Anti-Inflammatory Effect of ETAS®50 by Inhibiting Nuclear Factor-κB p65 Nuclear Import in Ultraviolet-B-Irradiated Normal Human Dermal Fibroblasts

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Ken Shirato

2018-01-01

Full Text Available Ultraviolet (UV irradiation induces proinflammatory responses in skin cells, including dermal fibroblasts, accelerating premature skin aging (photoaging. ETAS 50, a standardized extract from the Asparagus officinalis stem, is a novel and unique functional food that suppresses proinflammatory responses of hydrogen peroxide-stimulated skin fibroblasts and interleukin- (IL- 1β-stimulated hepatocytes. To elucidate its antiphotoaging potencies, we examined whether ETAS 50 treatment after UV-B irradiation attenuates proinflammatory responses of normal human dermal fibroblasts (NHDFs. UV-B-irradiated NHDFs showed reduced levels of the cytosolic inhibitor of nuclear factor-κB α (IκBα protein and increased levels of nuclear p65 protein. The nuclear factor-κB nuclear translocation inhibitor JSH-23 abolished UV-B irradiation-induced IL-1β mRNA expression, indicating that p65 regulates transcriptional induction. ETAS 50 also markedly suppressed UV-B irradiation-induced increases in IL-1β mRNA levels. Immunofluorescence analysis revealed that ETAS 50 retained p65 in the cytosol after UV-B irradiation. Western blotting also showed that ETAS 50 suppressed the UV-B irradiation-induced increases in nuclear p65 protein. Moreover, ETAS 50 clearly suppressed UV-B irradiation-induced distribution of importin-α protein levels in the nucleus without recovering cytosolic IκBα protein levels. These results suggest that ETAS 50 exerts anti-inflammatory effects on UV-B-irradiated NHDFs by suppressing the nuclear import machinery of p65. Therefore, ETAS 50 may prevent photoaging by suppressing UV irradiation-induced proinflammatory responses of dermal fibroblasts.

Dermal Contributions to Human Interfollicular Epidermal Architecture and Self-Renewal

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Kynan T. Lawlor

2015-11-01

Full Text Available The human interfollicular epidermis is renewed throughout life by populations of proliferating basal keratinocytes. Though interfollicular keratinocyte stem cells have been identified, it is not known how self-renewal in this compartment is spatially organized. At the epidermal-dermal junction, keratinocytes sit atop a heterogeneous mix of dermal cells that may regulate keratinocyte self-renewal by influencing local tissue architecture and signalling microenvironments. Focusing on the rete ridges and complementary dermal papillae in human skin, we review the identity and organisation of abundant dermal cells types and present evidence for interactions between the dermal microenvironment and the interfollicular keratinocytes.

Age-related disruption of autophagy in dermal fibroblasts modulates extracellular matrix components

Energy Technology Data Exchange (ETDEWEB)

Tashiro, Kanae [Skin Research Department, POLA Chemical Industries, Inc., Yokohama (Japan); Division of Pharmaceutical Cell Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka (Japan); Shishido, Mayumi [Skin Research Department, POLA Chemical Industries, Inc., Yokohama (Japan); Fujimoto, Keiko [Division of Pharmaceutical Cell Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka (Japan); Organelle Homeostasis Research Center, Kyushu University, Fukuoka (Japan); Hirota, Yuko [Division of Pharmaceutical Cell Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka (Japan); Yo, Kazuyuki; Gomi, Takamasa [Skin Research Department, POLA Chemical Industries, Inc., Yokohama (Japan); Tanaka, Yoshitaka, E-mail: tanakay@bioc.phar.kyushu-u.ac.jp [Division of Pharmaceutical Cell Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka (Japan); Organelle Homeostasis Research Center, Kyushu University, Fukuoka (Japan)

2014-01-03

Highlights: •Autophagosomes accumulate in aged dermal fibroblasts. •Autophagic degradation is impaired in aged dermal fibroblasts. •Autophagy disruption affects extracellular matrix components in dermal fibroblasts. -- Abstract: Autophagy is an intracellular degradative system that is believed to be involved in the aging process. The contribution of autophagy to age-related changes in the human skin is unclear. In this study, we examined the relationship between autophagy and skin aging. Transmission electron microscopy and immunofluorescence microscopy analyses of skin tissue and cultured dermal fibroblasts derived from women of different ages revealed an increase in the number of nascent double-membrane autophagosomes with age. Western blot analysis showed that the amount of LC3-II, a form associated with autophagic vacuolar membranes, was significantly increased in aged dermal fibroblasts compared with that in young dermal fibroblasts. Aged dermal fibroblasts were minimally affected by inhibition of autophagic activity. Although lipofuscin autofluorescence was elevated in aged dermal fibroblasts, the expression of Beclin-1 and Atg5—genes essential for autophagosome formation—was similar between young and aged dermal fibroblasts, suggesting that the increase of autophagosomes in aged dermal fibroblasts was due to impaired autophagic flux rather than an increase in autophagosome formation. Treatment of young dermal fibroblasts with lysosomal protease inhibitors, which mimic the condition of aged dermal fibroblasts with reduced autophagic activity, altered the fibroblast content of type I procollagen, hyaluronan and elastin, and caused a breakdown of collagen fibrils. Collectively, these findings suggest that the autophagy pathway is impaired in aged dermal fibroblasts, which leads to deterioration of dermal integrity and skin fragility.

Age-related disruption of autophagy in dermal fibroblasts modulates extracellular matrix components

International Nuclear Information System (INIS)

Tashiro, Kanae; Shishido, Mayumi; Fujimoto, Keiko; Hirota, Yuko; Yo, Kazuyuki; Gomi, Takamasa; Tanaka, Yoshitaka

2014-01-01

Highlights: •Autophagosomes accumulate in aged dermal fibroblasts. •Autophagic degradation is impaired in aged dermal fibroblasts. •Autophagy disruption affects extracellular matrix components in dermal fibroblasts. -- Abstract: Autophagy is an intracellular degradative system that is believed to be involved in the aging process. The contribution of autophagy to age-related changes in the human skin is unclear. In this study, we examined the relationship between autophagy and skin aging. Transmission electron microscopy and immunofluorescence microscopy analyses of skin tissue and cultured dermal fibroblasts derived from women of different ages revealed an increase in the number of nascent double-membrane autophagosomes with age. Western blot analysis showed that the amount of LC3-II, a form associated with autophagic vacuolar membranes, was significantly increased in aged dermal fibroblasts compared with that in young dermal fibroblasts. Aged dermal fibroblasts were minimally affected by inhibition of autophagic activity. Although lipofuscin autofluorescence was elevated in aged dermal fibroblasts, the expression of Beclin-1 and Atg5—genes essential for autophagosome formation—was similar between young and aged dermal fibroblasts, suggesting that the increase of autophagosomes in aged dermal fibroblasts was due to impaired autophagic flux rather than an increase in autophagosome formation. Treatment of young dermal fibroblasts with lysosomal protease inhibitors, which mimic the condition of aged dermal fibroblasts with reduced autophagic activity, altered the fibroblast content of type I procollagen, hyaluronan and elastin, and caused a breakdown of collagen fibrils. Collectively, these findings suggest that the autophagy pathway is impaired in aged dermal fibroblasts, which leads to deterioration of dermal integrity and skin fragility

Plasma rich in growth factors promotes dermal fibroblast proliferation, migration and biosynthetic activity.

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Anitua, E; Pino, A; Orive, G

2016-11-02

The use of plasma rich in growth factors (PRGF) has gained importance in many medical fields due to its regenerative potential. The aim of this study is to evaluate the effects of PRGF on primary skin fibroblasts assessing cell proliferation, migration and secretion of growth factors. The age of the patients from who PRGF was prepared was also studied to determine whether it influenced the outcomes. Human dermal fibroblasts were isolated from three healthy volunteers. Using PRGF-Endoret technology, PRGF was prepared from two groups of different ages (18-35 years and 50+ years). The effects of increasing concentration of PRGF (5%, 10% and 20%) on cell proliferation and migration was evaluated. Biosynthetic behaviour of cells was also analysed measuring vascular endothelial growth factor (VEGF), transforming growth factor b1 (TGFb1) and pro-collagen type I secreted levels with or without PRGF treatment. Mean platelet enrichment reached 2.4X and 2X in 18-35 and 50+ groups respectively. A dose-dependent response was observed in proliferation assays achieving the highest levels with 20% PRGF. Migration was also promoted in cells but not in a dose-dependent manner. Cell proliferation and migration outcomes obtained with PRGF (from both groups) were significantly higher compared to non-stimulated groups (pPRGF, however, with the exception of VEGF, no statistical significances were observed between the different age groups. Results from this study concluded that PRGF is safe and effective in stimulating skin regeneration by enhancing proliferation, migration and expression of pivotal bioactive molecules involved in wound healing and haemostasis.

Assessment of relevant factors and relationships concerning human dermal exposure to pesticides in greenhouse applications.

Science.gov (United States)

Martínez Vidal, Jose L; Egea González, Francisco J; Garrido Frenich, Antonia; Martínez Galera, María; Aguilera, Pedro A; López Carrique, Enrique

2002-08-01

Principal component analysis (PCA) was applied to the gas chromatographic data obtained from 23 different greenhouse trials. This was used to establish which factors, including application technique (very small, small, medium and large drop-size), crop characteristics (short/tall, thin/dense) and pattern application of the operator (walking towards or away from the treated area) are relevant to the dermal exposure levels of greenhouse applicators. The results showed that the highest exposure by pesticides during field applications in greenhouses, in the climatic conditions and in the crop conditions typical of a southern European country, occurs on the lower legs and front thighs of the applicators. Similar results were obtained by hierarchical cluster analysis (HCA). Drop-size seems to be very important in determining total exposure, while height and density of crops have little influence on total exposure under the conditions of the present study. No pesticide type is a major factor in total exposure. The application of multiple regression analysis (MRA) allowed assessment of the relationships between the pesticide exposure of the less affected parts of the body with the most affected parts.

Midface swelling reveals nasofrontal dermal sinus

International Nuclear Information System (INIS)

Houneida, Zaghouani Ben Alaya; Manel, Limeme; Latifa, Harzallah; Habib, Amara; Dejla, Bakir; Chekib, Kraiem

2012-01-01

Nasofrontal dermal sinuses are very rare and generally occur in children. This congenital malformation can be revealed by midface swelling, which can be complicated by local infection or neuromeningitis. Such complications make the dermal sinus a life-threatening disease. Two cases of nasofrontal dermal sinuses are reported in this work. The first case is an 11-month-old girl who presented with left orbitonasal soft tissue swelling accompanied by inflammation. Physical examination found fever, left orbitonasal thickening, and a puncture hole letting out pus. Computed tomography revealed microabscesses located at the left orbitonasal soft tissues, a frontal bone defect, and an intracranial cyst. Magnetic resonance imaging showed the transosseous tract between the glabella and the brain and affirmed the epidermoid nature of the intracranial cyst. The second case is a 7-year-old girl who presented with a nasofrontal non-progressive mass that intermittently secreted a yellow liquid through an external orifice located at the glabella. MRI revealed a cystic mass located in the deep layer of the glabellar skin related to an epidermoid cyst with a nasofrontal dermal sinus tract. In both cases, surgical excision was performed, and pathological confirmation was made for the diagnoses of dermal sinuses. The postoperative course was favorable. Through these cases, the authors stress the role of imaging methods in confirming the diagnosis and looking for associated cysts (dermoid and epidermoid) to improve recognition of this rare disease. Knowledge of the typical clinical presentations, imaging manifestations, and most common sites of occurrence of this malformation are needed to formulate a differential diagnosis.

Gene Expression Profiling of the Intact Dermal Sheath Cup of Human Hair Follicles.

Science.gov (United States)

Niiyama, Shiro; Ishimatsu-Tsuji, Yumiko; Nakazawa, Yosuke; Yoshida, Yuzo; Soma, Tsutomu; Ideta, Ritsuro; Mukai, Hideki; Kishimoto, Jiro

2018-04-24

Cells that constitute the dermal papillae of hair follicles might be derived from the dermal sheath, the peribulbar component of which is the dermal sheath cup. The dermal sheath cup is thought to include the progenitor cells of the dermal papillae and possesses hair inductive potential; however, it has not yet been well characterized. This study investigated the gene expression profile of the intact dermal sheath cup, and identified dermal sheath cup signature genes, including extracellular matrix components and BMP-binding molecules, as well as TGF-b1 as an upstream regulator. Among these, GREM2, a member of the BMP antagonists, was found by in situ hybridization to be highly specific to the dermal sheath cup, implying that GREM2 is a key molecule contributing to maintenance of the properties of the dermal sheath cup.

Integrin-linked kinase is required for TGF-β1 induction of dermal myofibroblast differentiation.

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Vi, Linda; de Lasa, Cristina; DiGuglielmo, Gianni M; Dagnino, Lina

2011-03-01

Cutaneous repair after injury requires activation of resident dermal fibroblasts and their transition to myofibroblasts. The key stimuli for myofibroblast formation are activation of transforming growth factor-β (TGF-β) receptors and mechanotransduction mediated by integrins and associated proteins. We investigated the role of integrin-linked kinase (ILK) in TGF-β1 induction of dermal fibroblast transition to myofibroblasts. ILK-deficient fibroblasts treated with TGF-β1 exhibited attenuation of Smad 2 and 3 phosphorylation, accompanied by impaired transcriptional activation of Smad targets, such as α-smooth muscle actin. These alterations were not limited to Smad-associated TGF-β1 responses, as stimulation of noncanonical mitogen-activated protein kinase pathways by this growth factor was also diminished in the absence of ILK. ILK-deficient fibroblasts exhibited abnormalities in the actin cytoskeleton, and did not form supermature focal adhesions or contractile F-actin stress fibers, indicating a severe impairment in their capacity to differentiate into myofibroblasts. These defects extended to the inability of cells to contract extracellular matrices when embedded in collagen lattices. We conclude that ILK is necessary to transduce signals implicated in the transition of dermal fibroblasts to myofibroblasts originating from matrix substrates and TGF-β1.

Role of clothing in both accelerating and impeding dermal absorption of airborne SVOCs

DEFF Research Database (Denmark)

Morrison, Glenn C.; Weschler, Charles J.; Bekö, Gabriel

2016-01-01

To assess the influence of clothing on dermal uptake of semi-volatile organic compounds (SVOCs), we measured uptake of selected airborne phthalates for an individual wearing clean clothes or air-exposed clothes and compared these results with dermal uptake for bare-skinned individuals under....... The individual wore either clean (fresh) cotton clothes or cotton clothes that had been exposed to the same chamber air concentrations for 9 days. For a 6-h exposure, the net amounts of DEP and DnBP absorbed when wearing fresh clothes were, respectively, 0.017 and 0.007 μg/kg/(μg/m3); for exposed clothes...... the results were 0.178 and 0.261 μg/kg/(μg/m3), respectively (values normalized by air concentration and body mass). When compared against the average results for bare-skinned participants, clean clothes were protective, whereas exposed clothes increased dermal uptake for DEP and DnBP by factors of 3.3 and 6...

Identification of eight novel coagulation factor XIII subunit A mutations: implied consequences for structure and function.

Science.gov (United States)

Ivaskevicius, Vytautas; Biswas, Arijit; Bevans, Carville; Schroeder, Verena; Kohler, Hans Peter; Rott, Hannelore; Halimeh, Susan; Petrides, Petro E; Lenk, Harald; Krause, Manuele; Miterski, Bruno; Harbrecht, Ursula; Oldenburg, Johannes

2010-06-01

Severe hereditary coagulation factor XIII deficiency is a rare homozygous bleeding disorder affecting one person in every two million individuals. In contrast, heterozygous factor XIII deficiency is more common, but usually not associated with severe hemorrhage such as intracranial bleeding or hemarthrosis. In most cases, the disease is caused by F13A gene mutations. Causative mutations associated with the F13B gene are rarer. We analyzed ten index patients and three relatives for factor XIII activity using a photometric assay and sequenced their F13A and F13B genes. Additionally, structural analysis of the wild-type protein structure from a previously reported X-ray crystallographic model identified potential structural and functional effects of the missense mutations. All individuals except one were heterozygous for factor XIIIA mutations (average factor XIII activity 51%), while the remaining homozygous individual was found to have severe factor XIII deficiency (<5% of normal factor XIII activity). Eight of the 12 heterozygous patients exhibited a bleeding tendency upon provocation. The identified missense (Pro289Arg, Arg611His, Asp668Gly) and nonsense (Gly390X, Trp664X) mutations are causative for factor XIII deficiency. A Gly592Ser variant identified in three unrelated index patients, as well as in 200 healthy controls (minor allele frequency 0.005), and two further Tyr167Cys and Arg540Gln variants, represent possible candidates for rare F13A gene polymorphisms since they apparently do not have a significant influence on the structure of the factor XIIIA protein. Future in vitro expression studies of the factor XIII mutations are required to confirm their pathological mechanisms.

SVOC exposure indoors: fresh look at dermal pathways.

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Weschler, C J; Nazaroff, W W

2012-10-01

This paper critically examines indoor exposure to semivolatile organic compounds (SVOCs) via dermal pathways. First, it demonstrates that--in central tendency--an SVOC's abundance on indoor surfaces and in handwipes can be predicted reasonably well from gas-phase concentrations, assuming that thermodynamic equilibrium prevails. Then, equations are developed, based upon idealized mass-transport considerations, to estimate transdermal penetration of an SVOC either from its concentration in skin-surface lipids or its concentration in air. Kinetic constraints limit air-to-skin transport in the case of SVOCs that strongly sorb to skin-surface lipids. Air-to-skin transdermal uptake is estimated to be comparable to or larger than inhalation intake for many SVOCs of current or potential interest indoors, including butylated hydroxytoluene, chlordane, chlorpyrifos, diethyl phthalate, Galaxolide, geranyl acetone, nicotine (in free-base form), PCB28, PCB52, Phantolide, Texanol and Tonalide. Although air-to-skin transdermal uptake is anticipated to be slow for bisphenol A, we find that transdermal permeation may nevertheless be substantial following its transfer to skin via contact with contaminated surfaces. The paper concludes with explorations of the influence of particles and dust on dermal exposure, the role of clothing and bedding as transport vectors, and the potential significance of hair follicles as transport shunts through the epidermis. Human exposure to indoor pollutants can occur through dietary and nondietary ingestion, inhalation, and dermal absorption. Many factors influence the relative importance of these pathways, including physical and chemical properties of the pollutants. This paper argues that exposure to indoor semivolatile organic compounds (SVOCs) through the dermal pathway has often been underestimated. Transdermal permeation of SVOCs can be substantially greater than is commonly assumed. Transport of SVOCs from the air to and through the skin is

DermAll nanomedicine for allergen-specific immunotherapy.

Science.gov (United States)

Garaczi, Edina; Szabó, Kornélia; Francziszti, László; Csiszovszki, Zsolt; Lőrincz, Orsolya; Tőke, Enikő R; Molnár, Levente; Bitai, Tamás; Jánossy, Tamás; Bata-Csörgő, Zsuzsanna; Kemény, Lajos; Lisziewicz, Julianna

2013-11-01

Allergen-specific immunotherapy (ASIT) the only disease-modifying treatment for IgE-mediated allergies is characterized with long treatment duration and high risk of side effects. We investigated the safety, immunogenicity and efficacy of a novel ASIT, called DermAll, in an experimental allergic rhinitis model. We designed and characterized DermAll-OVA, a synthetic plasmid pDNA/PEIm nanomedicine expressing ovalbumin (OVA) as model allergen. DermAll-OVA was administered topically with DermaPrep device to target Langerhans cells. To detect the clinical efficacy of DermAll ASIT we quantified the nasal symptoms and characterized the immunomodulatory activity of DermAll ASIT by measuring cytokine secretion after OVA-stimulation of splenocytes and antibodies from the sera. In allergic mice DermAll ASIT was as safe as Placebo, balanced the allergen-induced pathogenic TH2-polarized immune responses, and decreased the clinical symptoms by 52% [32%, 70%] compared to Placebo. These studies suggest that DermAll ASIT is safe and should significantly improve the immunopathology and symptoms of allergic diseases. A novel allergen-specific immunotherapy for IgE-mediated allergies is presented in this paper, using an experimental allergic rhinitis model and a synthetic plasmid pDNA/PEIm nanomedicine expressing ovalbumin as model allergen. Over 50% reduction of symptoms was found as the immune system's balance was favorably altered toward more TH2-polarized immune responses. Copyright © 2013 Elsevier Inc. All rights reserved.

Brain abscess as a manifestation of spinal dermal sinus

Directory of Open Access Journals (Sweden)

Parisa Emami-Naeini

2008-09-01

Full Text Available Parisa Emami-Naeini, Ali Mahdavi, Hamed Ahmadi, Nima Baradaran, Farideh NejatDepartment of Neurosurgery, Children’s Hospital Medical Center, Medical Sciences/University of Tehran, Tehran, IranAbstract: Dermal sinuses have been associated with a wide spectrum of clinical manifestations ranging from asymptomatic to drainage of purulent material from the sinus tract, inclusion tumors, meningitis, and spinal abscess. To date, there has been no documented report of brain abscess as a complication of spinal dermal sinus. Here, we report an 8-month-old girl who was presented initially with a brain abscess at early infancy but lumbar dermal sinus and associated spinal abscess were discovered afterwards. The probable mechanisms of this rare association have been discussed.Keywords: brain abscess, spinal dermal sinus, spinal abscess

Efek Pemberian Suntikan Subkutan Vitamin C Terhadap Luka Insisi Dermal

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Surya Darma

2014-09-01

Full Text Available Abstrak Vitamin C berfungsi sebagai kofaktor enzyme prolil dan lysil hydroxilase. Enzym tersebut berfungsi dalam proses hidroksilasi yang membentuk ikatan hidroksiprolin dan hidroksilisin pada fibroblast dalam membentuk kolagen. Selain itu Vitaimin C juga berfungsi meregulasi dan menstabilkan trankripsi gen mRNA prokolagen pada proses pembentukan kolagen di dermis. Berdasarkan hal tersebut diatas, peneliti tertarik untuk membuktikan apakah pemberian vitamin C subkutan disekitar luka insisi dermal berefek pada pembentukan kolagen yang lebih padat dalam proses penyembuhan luka. Metode: Penelitian eksperimental ini menggunakan tikus Wistar sebanyak 32 ekor, yang dibagi menjadi 2 kelompok yaitu 16 ekor sebagai kontrol dan 16 ekor lagi sebagai perlakuan. Pada kedua kelompok dilakukan insisi di punggung sepanjang 2 cm. Kelompok perlakuan diberi suntikan vitamin C subkutan disekitar luka insisi dermal sebanyak 9 mg (0,09ml, sedangkan kelompokkontrol tidak diberikan.Pada hari kelima dilakukan pengambilan jaringan luka pada kedua sampel untuk pemeriksaan kepadatan kolagen secara mikroskopik. Hasil:Kepadatan kolagen pada hari kelimamenunjukkan perbedaan yang bermakna dari efek penyuntikan vitamin C subkutan terhadap kepadatan kolagen (χ2 = 5,833; P<0,05. Kesimpulan: Penyuntikan vitamin C subkutan disekitar luka insisi dermal efektif dalam meeningkatan kepadatan kolagen. Kata kunci: suntikan vitamin C subkutan, kepadatan kolagen.Abstract Vitamin C functions as enzyme co-factor for prolyl and hidroxylase lysil. The enzyme functions in hydroxylase process that builds hydroxyproline and hydroxylysine bondsin fibroblast in the synthesis of collagen. Besides that, vitamin C also functions in regulating and stabilizing procollagen mRNA gen transcription in dermal collagen synthesis. Based on the facts above, researchers are interested to prove whether subcutaneous injection of vitamin C around dermal insisional wound would result in more compact collagen

Efek Pemberian Suntikan Subkutan Vitamin C Terhadap Luka Insisi Dermal

Directory of Open Access Journals (Sweden)

Surya Darma

2013-09-01

Full Text Available Abstrak Vitamin C berfungsi sebagai kofaktor enzyme prolil dan lysil hydroxilase. Enzym tersebut berfungsi dalam proses hidroksilasi yang membentuk ikatan hidroksiprolin dan hidroksilisin pada fibroblast dalam membentuk kolagen. Selain itu Vitaimin C juga berfungsi meregulasi dan menstabilkan trankripsi gen mRNA prokolagen pada proses pembentukan kolagen di dermis. Berdasarkan hal tersebut diatas, peneliti tertarik untuk membuktikan apakah pemberian vitamin C subkutan disekitar luka insisi dermal berefek pada pembentukan kolagen yang lebih padat dalam proses penyembuhan luka. Metode: Penelitian eksperimental ini menggunakan tikus Wistar sebanyak 32 ekor, yang dibagi menjadi 2 kelompok yaitu 16 ekor sebagai kontrol dan 16 ekor lagi sebagai perlakuan. Pada kedua kelompok dilakukan insisi di punggung sepanjang 2 cm. Kelompok perlakuan diberi suntikan vitamin C subkutan disekitar luka insisi dermal sebanyak 9 mg (0,09ml, sedangkan kelompokkontrol tidak diberikan.Pada hari kelima dilakukan pengambilan jaringan luka pada kedua sampel untuk pemeriksaan kepadatan kolagen secara mikroskopik. Hasil:Kepadatan kolagen pada hari kelimamenunjukkan perbedaan yang bermakna dari efek penyuntikan vitamin C subkutan terhadap kepadatan kolagen (χ2 = 5,833; P<0,05. Kesimpulan: Penyuntikan vitamin C subkutan disekitar luka insisi dermal efektif dalam meeningkatan kepadatan kolagen. Kata kunci: suntikan vitamin C subkutan, kepadatan kolagen. Abstract Vitamin C functions as enzyme co-factor for prolyl and hidroxylase lysil. The enzyme functions in hydroxylase process that builds hydroxyproline and hydroxylysine bondsin fibroblast in the synthesis of collagen. Besides that, vitamin C also functions in regulating and stabilizing procollagen mRNA gen transcription in dermal collagen synthesis. Based on the facts above, researchers are interested to prove whether subcutaneous injection of vitamin C around dermal insisional wound would result in more compact collagen

Melanogenesis in dermal melanocytes of Japanese Silky chicken embryos.

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Ortolani-Machado, C F; Freitas, P F; Faraco, C D

2009-08-01

The Japanese Silky chicken (SK) shows dermal and visceral hyperpigmentation. This study characterizes ultrastructurally the melanin granules developing in dermal melanocytes of the dorsal skin of SK, in an attempt to better understand the processes of melanogenesis in these permanently ectopic cells. The steps of melanogenesis are similar to those described for epidermal melanocytes, with melanosomes going from stage I to IV but, in SK, the maturation occurs in the cell body, as well as in the cytoplasmic processes. At stage III, the deposition of melanin is cumulative and can aggregate in rounded structures, which combine to turn into the mature granule. The final destiny of mature melanosomes is still unclear, although it was observed that dermal macrophages can accumulate melanin granules in their phagosomes. Even with the close proximity between melanocytes and other dermal cells, the transference of melanosomes was not observed. Our findings indicate that melanogenesis in dermal melanocytes in SK has the same morphological characteristics found in epidermal melanocytes, but the functional aspect still remains to be elucidated.

Keratinocytes express fibrillin and assemble microfibrils: implications for dermal matrix organization.

Science.gov (United States)

Haynes, S L; Shuttleworth, C A; Kielty, C M

1997-07-01

Fibrillin-containing microfibrils are key architectural structures of the upper dermis and integral components of the dermal elastic fibre network. Microfibril bundles intercalate into the dermal-epithelial junction and provide an elastic connection between the dermal elastic fibre network and the epidermis. Immunohistochemical studies have suggested that they are laid down both at the dermal-epithelial junction and in the deep dermis. While dermal fibroblasts are responsible for deposition of the elastin and microfibrillar components that comprise the elastic fibres of the deep dermis, the cellular origin of the microfibril bundles that extrude from the dermal-epithelial junction is not well defined. We have used fresh tissues, freshly isolated epidermis and primary human and porcine keratinocyte cultures to investigate the possibility that keratinocytes are responsible for deposition of these microfibrils. We have shown that keratinocytes in vivo and in vitro synthesize both fibrillin-1 and fibrillin-2, and assemble beaded microfibrils concurrently with expression of basement membrane collagen. These observations suggest that keratinocytes co-ordinate the secretion, deposition and assembly of these distinct structural elements of the dermal matrix, and have important implications for skin remodelling.

Update on botulinum toxin and dermal fillers.

Science.gov (United States)

Berbos, Zachary J; Lipham, William J

2010-09-01

The art and science of facial rejuvenation is an ever-evolving field of medicine, as evidenced by the continual development of new surgical and nonsurgical treatment modalities. Over the past 10 years, the use of botulinum toxin and dermal fillers for aesthetic purposes has risen sharply. Herein, we discuss properties of several commonly used injectable products and provide basic instruction for their use toward the goal of achieving facial rejuvenation. The demand for nonsurgical injection-based facial rejuvenation products has risen enormously in recent years. Used independently or concurrently, botulinum toxin and dermal filler agents offer an affordable, minimally invasive approach to facial rejuvenation. Botulinum toxin and dermal fillers can be used to diminish facial rhytides, restore facial volume, and sculpt facial contours, thereby achieving an aesthetically pleasing, youthful facial appearance.

Assessment of predictive dermal exposure to chemicals in the work environment

Directory of Open Access Journals (Sweden)

Agnieszka Jankowska

2017-08-01

Full Text Available Assessment of dermal exposure to chemicals in the work environment is problematic, mainly as a result of the lack of measurement data on occupational exposure to chemicals. Due to common prevalence of occupational skin exposure and its health consequences it is necessary to look for efficient solutions allowing for reliable exposure assessment. The aim of the study is to present predictive models used to assess non-measured dermal exposure, as well as to acquaint Polish users with the principles of the selected model functioning. This paper presents examples of models to assist the employer in the the assessment of occupational exposure associated with the skin contact with chemicals, developed in European Union (EU countries, as well as in countries outside the EU. Based on the literature data dermal exposure models EASE (Estimation and Assessment of Substance Exposure, COSHH Essentials (Control of Substances Hazardous to Health Regulations, DREAM (Dermal Exposure Assessment Method, Stoffenmanager , ECETOC TRA (European Centre for Ecotoxicology and Toxicology of Chemicals Targeted Risk Assessment, MEASE (Metal’s EASE, PHED (Pesticide Handlers Exposure Database, DERM (Dermal Exposure Ranking Method and RISKOFDERM (Risk Assessment of Occupational Dermal Exposure to Chemicals were briefly described. Moreover the characteristics of RISKOFDERM, guidelines for its use, information on input and output data were further detailed. Problem of full work shift dermal exposure assessment is described. An example of exposure assessment using RISKOFDERM and effectiveness evaluation to date were also presented. When no measurements are available, RISKOFDERM allows dermal exposure assessment and thus can improve the risk assessment quality and effectiveness of dermal risk management. Med Pr 2017;68(4:557–569

The radiological features of Goltz syndrome: Focal dermal hypoplasia

International Nuclear Information System (INIS)

Boothyrod, A.E.; Hall, C.M.

1988-01-01

Two female infants with Goltz syndrome (focal dermal hypoplasia) were recently investigated for severe feeding problems and failure to thrive. Both demonstrated severe skeletal malformations and marked gastrooesophageal reflux with laxity of the hiatus. One child (case 1) exhibited nasal regurgitation during feeding. Interestingly, both children had undergone surgery; Case 1 or a right parasagittal abdominal hernia associated with focal dermal hypoplasia of the abdominal wall and Case 2 for an exomphalos also associated with dermal hypoplasia. This observation suggests more widespread mesodermal abnormality. (orig./GDG)

Distinguishing a Rare Variant of Lipidized Dermatofibroma from Nonlipidized Dermatofibromas in a Patient with Hypothyroidism and Alopecia Areata

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Abdulla Farah

2017-06-01

Full Text Available Introduction. Lipidized dermatofibromas represent rare and often underrecognized variants of dermatofibromas. Histologically, dermatofibromas are composed of fibroblast-like spindle cells, foam cells, giant cells, siderophages, lymphocytes, capillaries, collagen fibers, and hyaline dermal collagen fibers. Lipidized dermatofibromas are characterized by numerous foam cells, Touton giant cells, and hyalinized wiry collagen in the stroma. Case report. We present a case of a 31-year-old woman with a history of hypothyroidism and alopecia areata, presenting with an enlarging 8 mm, firm erythematous nodule on her upper-mid back. Biopsy examination showed a cellular proliferation of spindle cells with peripheral collagen trapping and cholesterol clefts with associated foam cells and sclerosis, staining weakly positive for Factor XIIIa and negative for CD34. The diagnosis of a benign lipidized dermatofibroma was rendered. Conclusion. Lipidized dermatofibromas are rare histologic variants of dermatofibromas, biologically indolent, and should be distinguished from other cutaneous foamy histiocytic lesions, particularly xanthomas, which may alter patient management.

Merkel Cell Polyomavirus Infection of Animal Dermal Fibroblasts.

Science.gov (United States)

Liu, Wei; Krump, Nathan A; MacDonald, Margo; You, Jianxin

2018-02-15

Merkel cell polyomavirus (MCPyV) is the first polyomavirus to be associated with human cancer. Mechanistic studies attempting to fully elucidate MCPyV's oncogenic mechanisms have been hampered by the lack of animal models for MCPyV infection. In this study, we examined the ability of MCPyV-GFP pseudovirus (containing a green fluorescent protein [GFP] reporter construct), MCPyV recombinant virions, and several MCPyV chimeric viruses to infect dermal fibroblasts isolated from various model animals, including mouse ( Mus musculus ), rabbit ( Oryctolagus cuniculus ), rat ( Rattus norvegicus ), chimpanzee ( Pan troglodytes ), rhesus macaque ( Macaca mulatta ), patas monkey ( Erythrocebus patas ), common woolly monkey ( Lagothrix lagotricha ), red-chested mustached tamarin ( Saguinus labiatus ), and tree shrew ( Tupaia belangeri ). We found that MCPyV-GFP pseudovirus was able to enter the dermal fibroblasts of all species tested. Chimpanzee dermal fibroblasts were the only type that supported vigorous MCPyV gene expression and viral replication, and they did so to a level beyond that of human dermal fibroblasts. We further demonstrated that both human and chimpanzee dermal fibroblasts produce infectious MCPyV virions that can successfully infect new cells. In addition, rat dermal fibroblasts supported robust MCPyV large T antigen expression after infection with an MCPyV chimeric virus in which the entire enhancer region of the MCPyV early promoter has been replaced with the simian virus 40 (SV40) analog. Our results suggest that viral transcription and/or replication events represent the major hurdle for MCPyV cross-species transmission. The capacity of rat dermal fibroblasts to support MCPyV early gene expression suggests that the rat is a candidate model organism for studying viral oncogene function during Merkel cell carcinoma (MCC) oncogenic progression. IMPORTANCE MCPyV plays an important role in the development of a highly aggressive form of skin cancer, Merkel

Flexible Dermal Armor : Designs Learned from Nature

OpenAIRE

Chen, Irene Hsu

2015-01-01

Designs derived from nature have become a perfect blueprint for today's engineers and scientists to follow and implement. One particularly noted area is the defense industry, wherein flexible dermal armor inspired by nature has been pioneering many sophisticated technologies and designs in recent years. Designers today are considering borrowing aspects of flexibility and mobility of natural dermal armors to enhance the maneuverability of man-made armor by imitating the following mechanisms : ...

Granulocyte macrophage colony stimulating factor (GM-CSF biological actions on human dermal fibroblasts

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S Montagnani

2009-12-01

Full Text Available Fibroblasts are involved in all pathologies characterized by increased ExtraCellularMatrix synthesis, from wound healing to fibrosis. Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF is a cytokine isolated as an hemopoietic growth factor but recently indicated as a differentiative agent on endothelial cells. In this work we demonstrated the expression of the receptor for GM-CSF (GMCSFR on human normal skin fibroblasts from healthy subjects (NFPC and on a human normal fibroblast cell line (NHDF and we try to investigate the biological effects of this cytokine. Human normal fibroblasts were cultured with different doses of GM-CSF to study the effects of this factor on GMCSFR expression, on cell proliferation and adhesion structures. In addition we studied the production of some Extra-Cellular Matrix (ECM components such as Fibronectin, Tenascin and Collagen I. The growth rate of fibroblasts from healthy donors (NFPC is not augmented by GM-CSF stimulation in spite of increased expression of the GM-CSFR. On the contrary, the proliferation of normal human dermal fibroblasts (NHDF cell line seems more influenced by high concentration of GM-CSF in the culture medium. The adhesion structures and the ECM components appear variously influenced by GM-CSF treatment as compared to fibroblasts cultured in basal condition, but newly only NHDF cells are really induced to increase their synthesis activity. We suggest that the in vitro treatment with GM-CSF can shift human normal fibroblasts towards a more differentiated state, due or accompanied by an increased expression of GM-CSFR and that such “differentiation” is an important event induced by such cytokine.

Potential health effects associated with dermal exposure to occupational chemicals.

Science.gov (United States)

Anderson, Stacey E; Meade, B Jean

2014-01-01

There are a large number of workers in the United States, spanning a variety of occupational industries and sectors, who are potentially exposed to chemicals that can be absorbed through the skin. Occupational skin exposures can result in numerous diseases that can adversely affect an individual's health and capacity to perform at work. In general, there are three types of chemical-skin interactions of concern: direct skin effects, immune-mediated skin effects, and systemic effects. While hundreds of chemicals (metals, epoxy and acrylic resins, rubber additives, and chemical intermediates) present in virtually every industry have been identified to cause direct and immune-mediated effects such as contact dermatitis or urticaria, less is known about the number and types of chemicals contributing to systemic effects. In an attempt to raise awareness, skin notation assignments communicate the potential for dermal absorption; however, there is a need for standardization among agencies to communicate an accurate description of occupational hazards. Studies have suggested that exposure to complex mixtures, excessive hand washing, use of hand sanitizers, high frequency of wet work, and environmental or other factors may enhance penetration and stimulate other biological responses altering the outcomes of dermal chemical exposure. Understanding the hazards of dermal exposure is essential for the proper implementation of protective measures to ensure worker safety and health.

A Dermal Piercing Complicated by Mycobacterium fortuitum

Science.gov (United States)

Scroggins-Markle, Leslie; Kelly, Brent

2013-01-01

Background. Dermal piercings have recently become a fashion symbol. Common complications include hypertrophic scarring, rejection, local infection, contact allergy, and traumatic tearing. We report a rare case of Mycobacterium fortuitum following a dermal piercing and discuss its medical implications and treatments. Case. A previously healthy 19-year-old woman presented complaining of erythema and edema at the site of a dermal piercing on the right fourth dorsal finger. She was treated with a 10-day course of trimethoprim-sulfamethoxazole and one course of cephalexin by her primary care physician with incomplete resolution. The patient stated that she had been swimming at a local water park daily. A punch biopsy around the dermal stud was performed, and cultures with sensitivities revealed Mycobacterium fortuitum. The patient was treated with clarithromycin and ciprofloxacin for two months receiving full resolution. Discussion. Mycobacterium fortuitum is an infrequent human pathogen. This organism is a Runyon group IV, rapidly growing nontuberculous mycobacteria, often found in water,soil, and dust. Treatment options vary due to the size of the lesion. Small lesions are typically excised, while larger lesions require treatment for 2–6 months with antibiotics. We recommend a high level of suspicion for atypical mycobacterial infections in a piercing resistant to other therapies. PMID:24073343

A Dermal Piercing Complicated by Mycobacterium fortuitum

Directory of Open Access Journals (Sweden)

Trisha Patel

2013-01-01

Full Text Available Background. Dermal piercings have recently become a fashion symbol. Common complications include hypertrophic scarring, rejection, local infection, contact allergy, and traumatic tearing. We report a rare case of Mycobacterium fortuitum following a dermal piercing and discuss its medical implications and treatments. Case. A previously healthy 19-year-old woman presented complaining of erythema and edema at the site of a dermal piercing on the right fourth dorsal finger. She was treated with a 10-day course of trimethoprim-sulfamethoxazole and one course of cephalexin by her primary care physician with incomplete resolution. The patient stated that she had been swimming at a local water park daily. A punch biopsy around the dermal stud was performed, and cultures with sensitivities revealed Mycobacterium fortuitum. The patient was treated with clarithromycin and ciprofloxacin for two months receiving full resolution. Discussion. Mycobacterium fortuitum is an infrequent human pathogen. This organism is a Runyon group IV, rapidly growing nontuberculous mycobacteria, often found in water,soil, and dust. Treatment options vary due to the size of the lesion. Small lesions are typically excised, while larger lesions require treatment for 2–6 months with antibiotics. We recommend a high level of suspicion for atypical mycobacterial infections in a piercing resistant to other therapies.

Dermal fillers for facial soft tissue augmentation.

Science.gov (United States)

Dastoor, Sarosh F; Misch, Carl E; Wang, Hom-Lay

2007-01-01

Nowadays, patients are demanding not only enhancement to their dental (micro) esthetics, but also their overall facial (macro) esthetics. Soft tissue augmentation via dermal filling agents may be used to correct facial defects such as wrinkles caused by age, gravity, and trauma; thin lips; asymmetrical facial appearances; buccal fold depressions; and others. This article will review the pathogenesis of facial wrinkles, history, techniques, materials, complications, and clinical controversies regarding dermal fillers for soft tissue augmentation.

Post Kala-azar Dermal Leishmaniasis (PKDL) In vivo veritas

Indian Academy of Sciences (India)

Immunology LAB-1

2016-08-26

Aug 26, 2016 ... 50. 100. 150. 200. 250. 300. 0. 200. 400. 600. 800. 1000. 1200. 1400. 1600 ... Rapid diagnostic tests exist (PKDL?) • Effective ... ld (C t). No: of parasites/ 200 µl of blood. Post Kala Azar Dermal Leishmaniasis (PKDL); dermal ...

Relative absorption and dermal loading of chemical substances: Consequences for risk assessment

NARCIS (Netherlands)

Buist, H.E.; Schaafsma, G.; Sandt, J.J.M. van de

2009-01-01

Quantification of skin absorption is an essential step in reducing the uncertainty of dermal risk assessment. Data from literature indicate that the relative dermal absorption of substances is dependent on dermal loading. Therefore, an internal exposure calculated with absorption data determined at

DREAM: a method for semi-quantitative dermal exposure assessment

NARCIS (Netherlands)

Wendel de Joode, B. van; Brouwer, D.H.; Kromhout, H.; Hemmen, J.J. van

2003-01-01

This paper describes a new method (DREAM) for structured, semi-quantitative dermal exposure assessment for chemical or biological agents that can be used in occupational hygiene or epidemiology. It is anticipated that DREAM could serve as an initial assessment of dermal exposure, amongst others,

Dermal reflectivity determined by optical coherence tomography is an indicator of epidermal hyperplasia and dermal edema within inflamed skin

Science.gov (United States)

Phillips, Kevin G.; Wang, Yun; Levitz, David; Choudhury, Niloy; Swanzey, Emily; Lagowski, James; Kulesz-Martin, Molly; Jacques, Steven L.

2011-04-01

Psoriasis is a common inflammatory skin disease resulting from genetic and environmental alterations of cutaneous immune responses. While numerous therapeutic targets involved in the immunopathogenesis of psoriasis have been identified, the in vivo dynamics of inflammation in psoriasis remain unclear. We undertook in vivo time course focus-tracked optical coherence tomography (OCT) imaging to noninvasively document cutaneous alterations in mouse skin treated topically with Imiquimod (IMQ), an established model of a psoriasis-like disease. Quantitative appraisal of dermal architectural changes was achieved through a two parameter fit of OCT axial scans in the dermis of the form A(x, y, z) = ρ(x, y)exp [ - μ(x, y)z]. Ensemble averaging over 2000 axial scans per mouse in each treatment arm revealed no significant changes in the average dermal attenuation rate, , however the average local dermal reflectivity , decreased significantly following 1, 3, and 6 days of IMQ treatment (p humans.

Proof-of-Principle Dermal Decontamination Experiments: Swine Skin

Science.gov (United States)

2007-04-01

cycles and the measurements taken after each cycle were recorded. All water rinses were performed using tap water and applied using a gentle stream...uniform and highly reproducible. EpiDermFT ( EFT ) consists of organized basal, spinous, granular, and cornified epidermal layers analogous to those found...in vivo. The dermal compartment is composed of a collagen matrix containing viable normal human dermal fibroblasts (NHDF). EFT is mitotically and

Allogeneic human dermal fibroblasts are viable in peripheral blood mononuclear co-culture

Directory of Open Access Journals (Sweden)

Restu Syamsul Hadi

2014-08-01

Full Text Available Background Transplanted allogeneic dermal fibroblasts retain stem cell subpopulations, and are easily isolated, expanded and stored using standard techniques. Their potential for regenerative therapy of chronic wounds should be evaluated. The aim of this study was to determine allogeneic fibroblast viability in the presence of peripheral blood mononuclear cells (PBMC. Methods In this experimental study, fibroblasts were isolated from foreskin explants, expanded in the presence of serum, and stored using slow-freezing. We used one intervention group of allogeneic fibroblasts co-cultured with PBMC and 2 control groups of separate fibroblast and PBMC cultures.Fibroblasts were characterized by their collagen secretion and octamer-binding transcription factor 4 (OCT4 expression. Viability was evaluated using water soluble tetrazolium-1 (WST-1 proliferation assay. Absorbances were measured at 450 nm. Data analysis was performed by student’s paired t-test. Results Dermal fibroblasts were shown to secrete collagen, express OCT4, be recoverable after cryopreservation, and become attached to the culture dish in a co-culture with PBMC. Co-cultured and control fibroblasts had no significantly different cell viabilities (p>0.05. Calculated viable cell numbers increased 1.8 and 5.1-fold, respectively, at days 2 and 4 in vitro. Both groups showed comparable doubling times at days 2 and 4 in vitro. PBMC did not interfere with allogeneic fibroblast viability and proliferative capacity Conclusions Allogeneic fibroblasts remain viable and proliferate in the presence of host PBMC. Future research should evaluate allogeneic human dermal fibroblast competency in clinical settings. Dermal fibroblasts are a potential source for cell therapy in chronic wound management.

Changes in dermal papilla structures due to aging in the facial cheek region.

Science.gov (United States)

Mizukoshi, K; Yonekura, K; Futagawa, M; Nakamura, T; Hirayama, K; Takahashi, K

2015-05-01

In the past, it has been possible to measure the dermal papilla structures which are undulations between the epidermis and dermis by noninvasive method. However, almost all of previous studies were not intended to measure facial skin but another site of body. Here, we investigated age-dependent alterations for dermal papilla structures in the facial cheek region after elucidating the difference of characteristics between the body site. The surface of the dermis was observed under scanning electron microscope (SEM) using face and abdominal skin biopsy samples. A total of 90 Japanese women were investigated by in vivo confocal laser microscope (CLSM). The number and the shape in the horizontal cross-sectional images of the dermal papilla were analyzed. The facial skin had different characteristics in comparison to the abdominal skin by SEM observation. Under CLSM observation, we found abnormal dermal papilla structures which were accompanied by spots or enlarged pore areas and eliminated these structures from our analysis. We revealed a decrease in the number of normal dermal papilla structures with age and large individual differences at younger ages. We found abnormal dermal papilla structures and differences in the dermal papilla structures between face and other body site. With these taken into consideration, we could precisely investigate the aging alteration of normal dermal papilla structures in the face. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Measurements of Dermal and Oral Emissions from Humans

DEFF Research Database (Denmark)

Tsushima, Sayana; Bekö, Gabriel; Bossi, Rossana

2016-01-01

Human related pollutants (bioeffluents) emitted through skin and via exhaled breath were measured. Two climate chambers were connected via flexible ducts. The ducts were in one chamber attached to a breathing mask, through which five subjects exhaled on one occasion the air into the other chamber......: Human bioeffluents emitted orally were in this way isolated from those that were emitted dermally. On another occasion, the subjects exhaled the air into the chamber where they were sitting, thus exposure contained oral and dermal bioeffluents. Another twenty subjects assessed the air quality...... in the chambers. They judged the air quality in the chamber with dermal bioeffluents to be lower than in the one containing orally exhaled bioeffluents, and similar to the air quality in the chamber with all bioeffluents. The chemical compounds with slightly elevated concentrations differed between the two...

Handling of thermal paper: Implications for dermal exposure to bisphenol A and its alternatives.

Directory of Open Access Journals (Sweden)

Meghan R Bernier

Full Text Available Bisphenol A (BPA is an endocrine disrupting chemical used in a wide range of consumer products including photoactive dyes used in thermal paper. Recent studies have shown that dermal absorption of BPA can occur when handling these papers. Yet, regulatory agencies have largely dismissed thermal paper as a major source of BPA exposure. Exposure estimates provided by agencies such as the European Food Safety Authority (EFSA are based on assumptions about how humans interact with this material, stating that 'typical' exposures for adults involve only one handling per day for short periods of time (30% of individuals hold thermal paper with more than three fingertips, and >60% allow the paper to touch their palm. Only 11% of the participants we observed were consistent with the EFSA model for time of contact and dermal surface area. Mathematical modeling based on handling times we measured and previously published transfer coefficients, concentrations of BPA in paper, and absorption factors indicate the most conservative estimated intake from handling thermal paper in this population is 51.1 ng/kg/day, similar to EFSA's estimates of 59 ng/kg/day from dermal exposures. Less conservative estimates, using published data on concentrations in thermal paper and transfer rates to skin, indicate that exposures are likely significantly higher. Based on our observational data, we propose that the current models for estimating dermal BPA exposures are not consistent with normal human behavior and should be reevaluated.

Dermal γδ T-Cells Can Be Activated by Mitochondrial Damage-Associated Molecular Patterns.

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Martin G Schwacha

Full Text Available Gamma delta T-cells have been shown to be important to the early immunoinflammatory response to injury, independent of infection. This unique T-cell population acts to regulate cell trafficking and the release of cytokines and growth factors. We propose this sterile inflammatory response is in part associated with damage associated molecular patterns (DAMPs generated by major injury, such as burn, and mediated via toll-like receptors (TLRs. It is unknown whether DAMPs can activate resident γδ T-cells that reside in skin.Gamma delta T-cells were isolated from the skin of male C57BL/6 mice by enzymatic digestion. Mitochondrial DAMPs (MTDs were generated from mitochondria isolated from mouse livers by sonication and centrifugation. Dermal γδ T-cells were incubated with MTDs (0-500 μg/ml for 24 hr and cells and supernatants were collected for analysis.MTDs activated dermal γδ T-cells, as evidenced by increased TLR2 and TLR4 expression following in vitro exposure. MTDs also induced the production of inflammatory cytokines (IL-1β, IL-6, and growth factors (PDGF and VEGF by γδ T-cells.These findings herein support the concept that MTDs released after tissue/cellular injury are capable of activating dermal γδ T-cells. We propose that the activation of this unique T-cell population is central in the initiation of sterile inflammation and also contributes to the subsequent healing processes.

Differential Apoptosis in Mucosal and Dermal Wound Healing

Science.gov (United States)

Johnson, Ariel; Francis, Marybeth; DiPietro, Luisa Ann

2014-01-01

Objectives: Dermal and mucosal healing are mechanistically similar. However, scarring and closure rates are dramatically improved in mucosal healing, possibly due to differences in apoptosis. Apoptosis, nature's preprogrammed form of cell death, occurs via two major pathways, extrinsic and intrinsic, which intersect at caspase3 (Casp3) cleavage and activation. The purpose of this experiment was to identify the predominant pathways of apoptosis in mucosal and dermal wound healing. Approach: Wounds (1 mm biopsy punch) were made in the dorsal skin (n=3) or tongue (n=3) of female Balb/C mice aged 6 weeks. Wounds were harvested at 6 h, 24 h, day 3 (D3), D5, D7, and D10. RNA was isolated and analyzed using real time reverse transcriptase–polymerase chain reaction. Expression levels for genes in the intrinsic and extrinsic apoptotic pathways were compared in dermal and mucosal wounds. Results: Compared to mucosal healing, dermal wounds exhibited significantly higher expression of Casp3 (at D5; phealing compared to skin. Conclusion: Expression patterns of key regulators of apoptosis in wound healing indicate that apoptosis occurs predominantly through the intrinsic pathway in the healing mucosa, but predominantly through the extrinsic pathway in the healing skin. The identification of differences in the apoptotic pathways in skin and mucosal wounds may allow the development of therapeutics to improve skin healing. PMID:25493209

OPTIMIZATION OF RESULTS AND TREATMENT TIMING OF DEEP DERMAL BURNS IN CHILDREN

Directory of Open Access Journals (Sweden)

Konstantin Aleksandrovich Afonichev

2014-06-01

Full Text Available Untreated deep dermal burns in children are the cause of long-term treatment and severe cicatricial deformities, resulting in poor cosmetic results and greatly impairing functional outcome. The problem of optimizing the results and timing of treatment of deep burns in children in recent years has become particularly urgent. We observed 1853 children with III-A degree burns. Some of the children's burns healed spontaneously, which led to the development of scar deformities during the first six months after injury. Risk factors for their development, depending on the patient's age and location of the lesion, are pointed out. Other children underwent early tangential excision of eschar. The analysis of the treatment results showed that the use of early surgery in children with deep dermal burns can reduce treatment time, as well as significantly to improve the cosmetic and functional outcomes of trauma.

Volume correction in the aging hand: role of dermal fillers

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Rivkin AZ

2016-08-01

Full Text Available Alexander Z Rivkin David Geffen/UCLA School of Medicine Los Angeles, CA, USA Abstract: The hands, just like the face, are highly visible parts of the body. They age at a similar rate and demonstrate comparable changes with time, sun damage, and smoking. Loss of volume in the hands exposes underlying tendons, veins, and bony prominences. Rejuvenation of the hands with dermal fillers is a procedure with high patient satisfaction and relatively low risk for complications. This study will review relevant anatomy, injection technique, clinical safety, and efficacy of dermal filler volumization of the aging hand. Keywords: dermal fillers, hands, volumization, hyaluronic acid, calcium hydroxylapatite

Dermal exposure assessment of pesticide use: the case of sprayers in potato farms in the Colombian highlands.

Science.gov (United States)

Lesmes-Fabian, Camilo; García-Santos, Glenda; Leuenberger, Fanny; Nuyttens, David; Binder, Claudia R

2012-07-15

Quantifying dermal exposure to pesticides in farming systems in developing countries is of special interest for the estimation of potential health risks, especially when there is a lack of occupational hygiene regulations. In this paper we present the results of a dermal exposure assessment for the potato farming system in the highlands of Colombia, where farmers apply pesticides with hand pressure sprayers without any personal protective equipment. The fractioning of the pesticide, in terms of potential and actual dermal exposure, was determined via the whole-body dosimetry methodology, using the tracer uranine as pesticide surrogate, and luminescence spectrometry as analytical method. We assessed the three activities involved in pesticide management: preparation, application, and cleaning; analyzed three types of nozzles: one with a standard discharge and two modified by farmers to increase the discharge; and derived the protection factor given by work clothing. Our results suggest that to reduce the health risk, three aspects have to be considered: (i) avoiding the modification of nozzles, which affects the droplet size spectrum and increases the level of dermal exposure; (ii) using adequate work clothing made of thick fabrics, especially on the upper body parts; and (iii) cleaning properly the tank sprayer before the application activity. Copyright © 2012. Published by Elsevier B.V.

Toxicity of middle distillates from dermal exposure.

Science.gov (United States)

Koschier, F J

1999-02-01

This report focuses on recent studies that investigated the effects of kerosine dermal exposure on neurotoxicity and reproductive/developmental toxicity. Background toxicity information will also be reviewed for kerosine range mid distillates. The kerosine range mid distillates have a carbon range of C9-C16 and have a boiling range of 302-554 degrees F (150-290 degrees C). This category includes kerosine, aviation fuels (e.g., Jet A, JP-5 and JP-8), no. 1 fuel oil and diesel fuel oil. In general, the kerosine range mid distillates demonstrate relatively low acute toxicity by any route of exposure. High inhalation exposures can induce central nervous system depression characterized by ataxia, hypoactivity and prostration. Kerosines are known to cause skin irritation and inflammation under conditions of acute and repeated exposure in animals and humans, but are only slightly irritating to the eye and are not skin sensitizers. In addition, the absorption of kerosine range mid distillates through the skin has been demonstrated to be fairly rapid, but limited to approximately 10-15% of the applied dose after 24 hours. The kerosine range mid distillates are generally inactive in genetic toxicity tests although positive studies have been reported. Positive results, while at times equivocal, have been reported for straight run kerosine and jet fuel A in the mouse lymphoma assay with metabolic activation, and hydrodesulfurized kerosine (mouse) and jet fuel A (rat) in the bone marrow cytogenetic assay. Effects on the nervous and reproductive systems have been reported in humans and experimental animals under conditions where inhalation and dermal exposure to specific kerosine type fuels are sometimes difficult to separate. Recent laboratory studies have addressed this point and examined the effects of dermal exposure. In these studies, rats were exposed to hydrodesulfurized kerosine by skin application to determine the potential of dermal contact to cause reproductive

Assessment of platelet-derived growth factor using A splinted full thickness dermal wound model in bearded dragons (Pogona vitticeps).

Science.gov (United States)

Keller, Krista A; Paul-Murphy, Joanne; Weber, E P Scott; Kass, Philip H; Guzman, Sanchez-Migallon David; Park, Shin Ae; Raghunathan, Vijay Krishna; Gustavsen, Kate A; Murphy, Christopher J

2014-12-01

Wounds in reptiles are a common reason for presentation to a veterinarian. At this time there is limited information on effective topical medications to aid in wound closure. The objectives of this study were to translate the splinted, full-thickness dermal wound model, validated in mice, to the bearded dragon (Pogona vitticeps) and to determine the effect of topical becaplermin (BP), a platelet-derived growth factor (0.01%), on the rate of wound closure. Ten bearded dragons were anesthetized and two full-thickness cutaneous wounds were made on the dorsum of each lizard. Encircling splints were applied surrounding each wound and subsequently covered by a semi-occlusive dressing. Five lizards had one wound treated with BP and the adjacent wound treated with a vehicle control. Five additional lizards had one wound treated with saline and the second wound treated with a vehicle control. Wounds were imaged daily, and the wound area was measured using digital image analysis. The change in percentage wound closure over 17 days and the time to 50% wound closure was compared among the four treatment groups. There was no significant difference in wound closure rates between BP-treated and saline-treated wounds or in the time to 50% wound closure between any treatments. Vehicle-treated wounds adjacent to saline-treated wounds closed significantly slower than did BP (P dragons. When compared with saline, BP did not have a significant effect on wound closure rates, while the vehicle alone delayed wound closure. Histologic analysis of experimentally created wounds throughout the wound healing process is needed to further evaluate the effects of these treatments on reptile dermal wound healing.

Dermal exposure assessment of pesticide use: The case of sprayers in potato farms in the Colombian highlands

International Nuclear Information System (INIS)

Lesmes-Fabian, Camilo; García-Santos, Glenda; Leuenberger, Fanny; Nuyttens, David; Binder, Claudia R.

2012-01-01

Quantifying dermal exposure to pesticides in farming systems in developing countries is of special interest for the estimation of potential health risks, especially when there is a lack of occupational hygiene regulations. In this paper we present the results of a dermal exposure assessment for the potato farming system in the highlands of Colombia, where farmers apply pesticides with hand pressure sprayers without any personal protective equipment. The fractioning of the pesticide, in terms of potential and actual dermal exposure, was determined via the whole-body dosimetry methodology, using the tracer uranine as pesticide surrogate, and luminescence spectrometry as analytical method. We assessed the three activities involved in pesticide management: preparation, application, and cleaning; analyzed three types of nozzles: one with a standard discharge and two modified by farmers to increase the discharge; and derived the protection factor given by work clothing. Our results suggest that to reduce the health risk, three aspects have to be considered: (i) avoiding the modification of nozzles, which affects the droplet size spectrum and increases the level of dermal exposure; (ii) using adequate work clothing made of thick fabrics, especially on the upper body parts; and (iii) cleaning properly the tank sprayer before the application activity. - Highlights: ► We assessed dermal exposure to pesticides in the potato farming system in Colombia. ► High potential exposure was found in lower body parts during the application. ► High actual exposure was found in arms and back due to inadequate protection. ► There is a high health risk of using Metamidophos under current working conditions.

Dermal pocketing following distal finger replantation.

Science.gov (United States)

Puhaindran, Mark E; Paavilainen, Pasi; Tan, David M K; Peng, Yeong Pin; Lim, Aymeric Y T

2010-08-01

Replantation is an ideal technique for reconstruction following fingertip amputation as it provides 'like for like' total reconstruction of the nail complex, bone pulp tissue and skin with no donor-site morbidity. However, fingertips are often not replanted because veins cannot be found or are thought to be too small to repair. Attempts at 'cap-plasty' or pocketing of replanted tips with and without microvascular anastomosis have been done in the past with varying degrees of success. We prospectively followed up a group of patients who underwent digital replantation and dermal pocketing in the palm to evaluate the outcome of this procedure. There were 10 patients with 14 amputated digits (two thumbs, five index, four middle, two ring and one little) who underwent dermal pocketing of the amputated digit following replantation. Among the 14 digits that were treated with dermal pocketing, 11 survived completely, one had partial atrophy and two were completely lost. Complications encountered included finger stiffness (two patients) and infection of the replanted fingertip with osteomyelitis of the distal phalanx (one patient). We believe that this technique can help increase the chance of survival for distal replantation with an acceptable salvage rate of 85% in our series. Copyright 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Estimating dermal transfer from PCB-contaminated porous surfaces.

Science.gov (United States)

Slayton, T M; Valberg, P A; Wait, A D

1998-06-01

Health risks posed by dermal contact with PCB-contaminated porous surfaces have not been directly demonstrated and are difficult to estimate indirectly. Surface contamination by organic compounds is commonly assessed by collecting wipe samples with hexane as the solvent. However, for porous surfaces, hexane wipe characterization is of limited direct use when estimating potential human exposure. Particularly for porous surfaces, the relationship between the amount of organic material collected by hexane and the amount actually picked up by, for example, a person's hand touch is unknown. To better mimic PCB pickup by casual hand contact with contaminated concrete surfaces, we used alternate solvents and wipe application methods that more closely mimic casual dermal contact. Our sampling results were compared to PCB pickup using hexane-wetted wipes and the standard rubbing protocol. Dry and oil-wetted samples, applied without rubbing, picked up less than 1% of the PCBs picked up by the standard hexane procedure; with rubbing, they picked up about 2%. Without rubbing, saline-wetted wipes picked up 2.5%; with rubbing, they picked up about 12%. While the nature of dermal contact with a contaminated surface cannot be perfectly reproduced with a wipe sample, our results with alternate wiping solvents and rubbing methods more closely mimic hand contact than the standard hexane wipe protocol. The relative pickup estimates presented in this paper can be used in conjunction with site-specific PCB hexane wipe results to estimate dermal pickup rates at sites with PCB-contaminated concrete.

Measurements of Dermal Uptake of Nicotine Directly from Air and Clothing

DEFF Research Database (Denmark)

Bekö, Gabriel; Morrison, Glenn; Weschler, Charles J.

2016-01-01

Dermal uptake directly from air is a significant contributor to total exposure for certain organic compounds, and has been recently experimentally verified for two phthalates. The objective of the current study was to investigate whether airborne nicotine can be dermally absorbed. Two bare-skinne...

Evaluation of dermal wound healing activity of synthetic peptide SVVYGLR.

Science.gov (United States)

Uchinaka, Ayako; Kawaguchi, Naomasa; Ban, Tsuyoshi; Hamada, Yoshinosuke; Mori, Seiji; Maeno, Yoshitaka; Sawa, Yoshiki; Nagata, Kohzo; Yamamoto, Hirofumi

2017-09-23

SVVYGLR peptide (SV peptide) is a 7-amino-acid sequence with angiogenic properties that is derived from osteopontin in the extracellular matrix and promotes differentiation of fibroblasts to myofibroblast-like cells and the production of collagen type Ⅲ by cardiac fibroblasts. However, the effects of SV peptide on dermal cells and tissue are unknown. In this study, we evaluated the effects of this peptide in a rat model of dermal wound healing. The synthetic SV peptide was added to dermal fibroblasts or keratinocytes, and their cellular motility was evaluated. In an in vivo wound healing exeriment, male rats aged 8 weeks were randomly assigned to the SV peptide treatment, non-treated control, or phosphate-buffered saline (PBS) groups. Wound healing was assessed by its repair rate and histological features. Scratch assay and cell migration assays using the Chemotaxicell method showed that SV peptide significantly promoted the cell migration in both fibroblasts and keratinocytes. In contrast the proliferation potency of these cells was not affected by SV peptide. In the rat model, wound healing progressed faster in the SV peptide-treated group than in the control and PBS groups. The histopathological analyses showed that the SV peptide treatment stimulated the migration of fibroblasts to the wound area and increased the number of myofibroblasts. Immunohistochemical staining showed a marked increase of von Willebland factor-positive neomicrovessels in the SV peptide-treated group. In conclusion, SV peptide has a beneficial function to promote wound healing by stimulating granulation via stimulating angiogenesis, cell migration, and the myofibroblastic differentiation of fibroblasts. Copyright © 2017 Elsevier Inc. All rights reserved.

Human dermal absorption of chlorinated organophosphate flame retardants; implications for human exposure

Energy Technology Data Exchange (ETDEWEB)

Abou-Elwafa Abdallah, Mohamed, E-mail: mae_abdallah@yahoo.co.uk [Division of Environmental Health and Risk Management, School of Geography, Earth, and Environmental Sciences, University of Birmingham, Birmingham B15 2TT (United Kingdom); Department of Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut (Egypt); Pawar, Gopal; Harrad, Stuart [Division of Environmental Health and Risk Management, School of Geography, Earth, and Environmental Sciences, University of Birmingham, Birmingham B15 2TT (United Kingdom)

2016-01-15

Tris-2-chloroethyl phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tris-1,3-dichloropropyl phosphate (TDCIPP) are organophosphate flame retardants (PFRs) widely applied in a plethora of consumer products despite their carcinogenic potential. Human dermal absorption of these PFRs is investigated for the first time using human ex vivo skin and EPISKIN™ models. Results of human ex vivo skin experiments revealed 28%, 25% and 13% absorption of the applied dose (500 ng/cm{sup 2}, finite dose) of TCEP, TCIPP and TDCIPP, respectively after 24 h exposure. The EPISKIN™ model showed enhanced permeability values (i.e. weaker barrier), that were respectively 16%, 11% and 9% for TCEP, TCIPP and TDCIPP compared to human ex vivo skin. However, this difference was not significant (P > 0.05). Estimated permeability constants (K{sub p}, cm/h) showed a significant negative correlation with log K{sub ow} for the studied contaminants. The effect of hand-washing on dermal absorption of PFRs was investigated. Washing reduced overall dermal absorption, albeit to varying degrees depending on the physicochemical properties of the target PFRs. Moreover, slight variations of the absorbed dose were observed upon changing the dosing solution from acetone to 20% Tween 80 in water, indicating the potential influence of the dose vehicle on the dermal absorption of PFRs. Finally, estimated dermal uptake of the studied PFRs via contact with indoor dust was higher in UK toddlers (median ΣPFRs = 36 ng/kg bw day) than adults (median ΣPFRs = 4 ng/kg bw day). More research is required to fully elucidate the toxicological implications of such exposure. - Highlights: • Human dermal absorption of PFRs was studied using human ex vivo skin and EPISKIN™. • Absorbed fractions of TCEP, TCIPP and TDCIPP were 28%, 25% and 13% of applied dose. • Permeability constants showed significant negative correlation to log K{sub ow} of PFRs. • Skin washing reduced the overall dermal

Human dermal absorption of chlorinated organophosphate flame retardants; implications for human exposure

International Nuclear Information System (INIS)

Abou-Elwafa Abdallah, Mohamed; Pawar, Gopal; Harrad, Stuart

2016-01-01

Tris-2-chloroethyl phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tris-1,3-dichloropropyl phosphate (TDCIPP) are organophosphate flame retardants (PFRs) widely applied in a plethora of consumer products despite their carcinogenic potential. Human dermal absorption of these PFRs is investigated for the first time using human ex vivo skin and EPISKIN™ models. Results of human ex vivo skin experiments revealed 28%, 25% and 13% absorption of the applied dose (500 ng/cm 2 , finite dose) of TCEP, TCIPP and TDCIPP, respectively after 24 h exposure. The EPISKIN™ model showed enhanced permeability values (i.e. weaker barrier), that were respectively 16%, 11% and 9% for TCEP, TCIPP and TDCIPP compared to human ex vivo skin. However, this difference was not significant (P > 0.05). Estimated permeability constants (K p , cm/h) showed a significant negative correlation with log K ow for the studied contaminants. The effect of hand-washing on dermal absorption of PFRs was investigated. Washing reduced overall dermal absorption, albeit to varying degrees depending on the physicochemical properties of the target PFRs. Moreover, slight variations of the absorbed dose were observed upon changing the dosing solution from acetone to 20% Tween 80 in water, indicating the potential influence of the dose vehicle on the dermal absorption of PFRs. Finally, estimated dermal uptake of the studied PFRs via contact with indoor dust was higher in UK toddlers (median ΣPFRs = 36 ng/kg bw day) than adults (median ΣPFRs = 4 ng/kg bw day). More research is required to fully elucidate the toxicological implications of such exposure. - Highlights: • Human dermal absorption of PFRs was studied using human ex vivo skin and EPISKIN™. • Absorbed fractions of TCEP, TCIPP and TDCIPP were 28%, 25% and 13% of applied dose. • Permeability constants showed significant negative correlation to log K ow of PFRs. • Skin washing reduced the overall dermal absorption of target PFRs

Dermal pharmacokinetics of microemulsion formulations determined by in vivo microdialysis

DEFF Research Database (Denmark)

Kreilgaard, Mads

2001-01-01

To investigate the potential of improving dermal drug delivery of hydrophilic and lipophilic substances by formulation in microemulsion vehicles and to establish a reliable pharmacokinetic model to analyze cutaneous microdialysis data.......To investigate the potential of improving dermal drug delivery of hydrophilic and lipophilic substances by formulation in microemulsion vehicles and to establish a reliable pharmacokinetic model to analyze cutaneous microdialysis data....

The basic science of dermal fillers: past and present Part II: adverse effects.

Science.gov (United States)

Gilbert, Erin; Hui, Andrea; Meehan, Shane; Waldorf, Heidi A

2012-09-01

The ideal dermal filler should offer long-lasting aesthetic improvement with a minimal side-effect profile. It should be biocompatible and stable within the injection site, with the risk of only transient undesirable effects from injection alone. However, all dermal fillers can induce serious and potentially long-lasting adverse effects. In Part II of this paper, we review the most common adverse effects related to dermal filler use.

Pesticide risk assessment: A study on inhalation and dermal exposure to 2,4-D and paraquat among Malaysian paddy farmers.

Science.gov (United States)

Baharuddin, Mohd Rafee B; Sahid, Ismail B; Noor, Mohamad Azhar B Mohd; Sulaiman, Norela; Othman, Fadzil

2011-01-01

A cross-section analytical study was conducted to evaluate the risk of pesticide exposure to those applying the Class II pesticides 2,4-D and paraquat in the paddy-growing areas of Kerian, Perak, Malaysia. It investigated the influence of weather on exposure as well as documented health problems commonly related to pesticide exposure. Potential inhalation and dermal exposure for 140 paddy farmers (handlers of pesticides) were assessed. Results showed that while temperature and humidity affected exposure, windspeed had the strongest impact on pesticide exposure via inhalation. However, the degree of exposure to both herbicides via inhalation was below the permissible exposure limits set by United States National Institute of Occupational Safety and Health (NIOSH). Dermal Exposure Assessment Method (DREAM) readings showed that dermal exposure with manual spraying ranged from moderate to high. With motorized sprayers, however, the level of dermal exposure ranged from low to moderate. Dermal exposure was significantly negatively correlated with the usage of protective clothing. Various types of deleterious health effects were detected among users of manual knapsack sprayers. Long-term spraying activities were positively correlated with increasing levels of the gamma-glutamyl transpeptidase (GGT) liver enzyme. The type of spraying equipment, usage of proper protective clothing and adherence to correct spraying practices were found to be the most important factors influencing the degree of pesticide exposure among those applying pesticides.

Dermal exposure assessment to benzene and toluene using charcoal cloth pads

NARCIS (Netherlands)

Wendel de Joode, B. van; Tielemans, E.; Vermeulen, R.; Wegh, H.; Kromhout, H.

2005-01-01

Charcoal cloth pads have been used to assess volatile chemicals on the skin in a laboratory setting; however, they have not yet been applied to measure dermal exposure in occupational settings. This study aimed at evaluating whether charcoal pads can be used to assess dermal exposure to benzene and

Dermal insecticide residues from birds inhabiting an orchard

Science.gov (United States)

Vyas, N.B.; Spann, J.W.; Hulse, C.S.; Gentry, S.; Borges, S.L.

2007-01-01

The US Environmental Protection Agency conducts risk assessments of insecticide applications to wild birds using a model that is limited to the dietary route of exposure. However, free-flying birds are also exposed to insecticides via the inhalation and dermal routes. We measured azinphos-methyl residues on the skin plus feathers and the feet of brown-headed cowbirds (Molothrus ater) in order to quantify dermal exposure to songbirds that entered and inhabited an apple (Malus x domestica) orchard following an insecticide application. Exposure to azinphos-methyl was measured by sampling birds from an aviary that was built around an apple tree. Birds sampled at 36 h and 7-day post-application were placed in the aviary within 1 h after the application whereas birds exposed for 3 days were released into the aviary 4-day post-application. Residues on vegetation and soil were also measured. Azinphos-methyl residues were detected from the skin plus feathers and the feet from all exposure periods. Our results underscore the importance of incorporating dermal exposure into avian pesticide risk assessments.

[Penile augmentation and elongation using autologous dermal-fat strip grafting].

Science.gov (United States)

Yang, Zhe; Li, Yang-qun; Tang, Yong; Chen, Wen; Li, Qiang; Zhou, Chuan-de; Zhao, Mu-xin; Hu, Chun-mei

2012-05-01

To investigate the effect of autologous dermal-fat strip grafting in penile augmentation and elongation. From May 2004 to December 2010, 24 patients underwent penile enhancement with free dermal-fat strip grafting. Through suprapubic incision, the superior suspensory ligament and part deep suspensory ligament are cutted off to lengthen the penis. The resulted dead space is filled with the autologous dermal-fat strip (6.0-9.5 cm in length, 1.2-1.5 cm in width and 0.6-0.8 cm in depth) to enhance the penis. Primary healing was achieved in 23 cases. Incisional fat liquefaction happened in one case which healed after dressing change. The penile appearance was satisfactory both at rest or erection. The penile length and circumference increased by 2.5-4.8 cm (average, 3.2 cm) and 1.8-3.0 cm (average, 2.4 cm), respectively. 18 patients were followed up for 3 months to 5 years. All the patients were satisfactory on the cosmetic and functional results. No complication happened. It is safe and effective for penile augmention and elongation with autologous dermal-fat strip grafting and disconnection of penile suspensory ligament.

INVIVO DEGRADATION OF PROCESSED DERMAL SHEEP COLLAGEN EVALUATED WITH TRANSMISSION ELECTRON-MICROSCOPY

NARCIS (Netherlands)

VANWACHEM, PB; VANLUYN, MJA; NIEUWENHUIS, P; KOERTEN, HK; DAMINK, LO; TENHOOPEN, H; FEIJEN, J

The in vivo degradation of hexamethylenediisocyanate-tanned dermal sheep collagen was studied with transmission electron microscopy. Discs of hexamethylenediisocyanate-tanned dermal sheep collagen were subcutaneously implanted in rats. Both an intra- and an extracellular route of degradation could

Dermal fillers in aesthetics: an overview of adverse events and treatment approaches.

Science.gov (United States)

Funt, David; Pavicic, Tatjana

2015-01-01

The ever-expanding range of dermal filler products for aesthetic soft tissue augmentation is of benefit for patients and physicians, but as indications and the number of procedures performed increase, the number of complications will likely also increase. To describe potential adverse events associated with dermal fillers and to provide structured and clear guidance on their treatment and avoidance. Reports of dermal filler complications in the medical literature were reviewed and, based on the publications retrieved and the authors' extensive experience, recommendations for avoiding and managing complications are provided. Different dermal fillers have widely varying properties, associated risks, and injection requirements. All dermal fillers have the potential to cause complications. Most are related to volume and technique, though some are associated with the material itself. The majority of adverse reactions are mild and transient, such as bruising and trauma-related edema. Serious adverse events are rare, and most are avoidable with proper planning and technique. For optimum outcomes, aesthetic physicians should have a detailed understanding of facial anatomy; the individual characteristics of available fillers; their indications, contraindications, benefits, and drawbacks; and ways to prevent and avoid potential complications.

Dermal exposure assessment of pesticide use: The case of sprayers in potato farms in the Colombian highlands

Energy Technology Data Exchange (ETDEWEB)

Lesmes-Fabian, Camilo, E-mail: camilo.lesmes@geographie.uni-muenchen.de [Department of Geography, University of Munich, Luisenstrasse 37, D-80333 Munich (Germany); Institute for Systems Science, Innovation and Sustainability Research, Karl-Franzens University of Graz, Merangase 18/I, A-8010 Graz (Austria); Garcia-Santos, Glenda [Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich (Switzerland); Leuenberger, Fanny [Institute of Geology, Swiss Federal Institute of Technology (ETH), Sonneggstrasse 5, 8092 Zurich (Switzerland); Nuyttens, David [Institute for Agricultural and Fisheries Research, Technology and Food Science Unit, Agricultural Engineering, Burg. van Gansberghelaan 115 bus 1, 9820 Merelbeke (Belgium); Binder, Claudia R. [Department of Geography, University of Munich, Luisenstrasse 37, D-80333 Munich (Germany); Institute for Systems Science, Innovation and Sustainability Research, Karl-Franzens University of Graz, Merangase 18/I, A-8010 Graz (Austria)

2012-07-15

Quantifying dermal exposure to pesticides in farming systems in developing countries is of special interest for the estimation of potential health risks, especially when there is a lack of occupational hygiene regulations. In this paper we present the results of a dermal exposure assessment for the potato farming system in the highlands of Colombia, where farmers apply pesticides with hand pressure sprayers without any personal protective equipment. The fractioning of the pesticide, in terms of potential and actual dermal exposure, was determined via the whole-body dosimetry methodology, using the tracer uranine as pesticide surrogate, and luminescence spectrometry as analytical method. We assessed the three activities involved in pesticide management: preparation, application, and cleaning; analyzed three types of nozzles: one with a standard discharge and two modified by farmers to increase the discharge; and derived the protection factor given by work clothing. Our results suggest that to reduce the health risk, three aspects have to be considered: (i) avoiding the modification of nozzles, which affects the droplet size spectrum and increases the level of dermal exposure; (ii) using adequate work clothing made of thick fabrics, especially on the upper body parts; and (iii) cleaning properly the tank sprayer before the application activity. - Highlights: Black-Right-Pointing-Pointer We assessed dermal exposure to pesticides in the potato farming system in Colombia. Black-Right-Pointing-Pointer High potential exposure was found in lower body parts during the application. Black-Right-Pointing-Pointer High actual exposure was found in arms and back due to inadequate protection. Black-Right-Pointing-Pointer There is a high health risk of using Metamidophos under current working conditions.

Hydroquinone PBPK model refinement and application to dermal exposure.

Science.gov (United States)

Poet, Torka S; Carlton, Betsy D; Deyo, James A; Hinderliter, Paul M

2010-11-01

A physiologically based pharmacokinetic (PBPK) model for hydroquinone (HQ) was refined to include an expanded description of HQ-glucuronide metabolites and a description of dermal exposures to support route-to-route and cross-species extrapolation. Total urinary excretion of metabolites from in vivo rat dermal exposures was used to estimate a percutaneous permeability coefficient (K(p); 3.6×10(-5) cm/h). The human in vivo K(p) was estimated to be 1.62×10(-4) cm/h, based on in vitro skin permeability data in rats and humans and rat in vivo values. The projected total multi-substituted glutathione (which was used as an internal dose surrogate for the toxic glutathione metabolites) was modeled following an exposure scenario based on submersion of both hands in a 5% aqueous solution of HQ (similar to black and white photographic developing solution) for 2 h, a worst-case exposure scenario. Total multi-substituted glutathione following this human dermal exposure scenario was several orders of magnitude lower than the internal total glutathione conjugates in rats following an oral exposure to the rat NOEL of 20 mg/kg. Thus, under more realistic human dermal exposure conditions, it is unlikely that toxic glutathione conjugates (primarily the di- and, to a lesser degree, the tri-glutathione conjugate) will reach significant levels in target tissues. Copyright © 2010. Published by Elsevier Ltd.

Dermal Sensitization Potential of Triethyleneglycol Dinitrate (TEGDN) in Guinea Pigs

Science.gov (United States)

1989-01-01

mutagenicity assay, acute oral toxicity tests in rats and mice, acute dermal toxicity in rabbits, dermal and ocular irritation studies in rabbits, and...conditions: 85E0102 had diffuse tracheitis, mild endocarditis , mild hepatitis, and diffuse pigment granules in the small intestine; 85E0103 had mild...severe ulceration progressing to necrosis. Sensitization is manifested as indirect inflammation mediated by components of the immune system in

Proliferation-promoting effect of platelet-rich plasma on human adipose-derived stem cells and human dermal fibroblasts.

Science.gov (United States)

Kakudo, Natsuko; Minakata, Tatsuya; Mitsui, Toshihito; Kushida, Satoshi; Notodihardjo, Frederik Zefanya; Kusumoto, Kenji

2008-11-01

This study evaluated changes in platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 release from platelets by platelet-rich plasma activation, and the proliferation potential of activated platelet-rich plasma and platelet-poor plasma on human adipose-derived stem cells and human dermal fibroblasts. Platelet-rich plasma was prepared using a double-spin method, with the number of platelets counted in each preparation stage. Platelet-rich and platelet-poor plasma were activated with autologous thrombin and calcium chloride, and levels of platelet-released PDGF-AB and TGF-beta1 were determined by enzyme-linked immunosorbent assay. Cells were cultured for 1, 4, or 7 days in serum-free Dulbecco's Modified Eagle Medium supplemented with 5% whole blood plasma, nonactivated platelet-rich plasma, nonactivated platelet-poor plasma, activated platelet-rich plasma, or activated platelet-poor plasma. In parallel, these cells were cultured for 1, 4, or 7 days in serum-free Dulbecco's Modified Eagle Medium supplemented with 1%, 5%, 10%, or 20% activated platelet-rich plasma. The cultured human adipose-derived stem cells and human dermal fibroblasts were assayed for proliferation. Platelet-rich plasma contained approximately 7.9 times as many platelets as whole blood, and its activation was associated with the release of large amounts of PDGF-AB and TGF-beta1. Adding activated platelet-rich or platelet-poor plasma significantly promoted the proliferation of human adipose-derived stem cells and human dermal fibroblasts. Adding 5% activated platelet-rich plasma to the medium maximally promoted cell proliferation, but activated platelet-rich plasma at 20% did not promote it. Platelet-rich plasma can enhance the proliferation of human adipose-derived stem cells and human dermal fibroblasts. These results support clinical platelet-rich plasma application for cell-based, soft-tissue engineering and wound healing.

Characterization of dermal plates from armored catfish Pterygoplichthys pardalis reveals sandwich-like nanocomposite structure.

Science.gov (United States)

Ebenstein, Donna; Calderon, Carlos; Troncoso, Omar P; Torres, Fernando G

2015-05-01

Dermal plates from armored catfish are bony structures that cover their body. In this paper we characterized structural, chemical, and nanomechanical properties of the dermal plates from the Amazonian fish Pterygoplichthys pardalis. Analysis of the morphology of the plates using scanning electron microscopy (SEM) revealed that the dermal plates have a sandwich-like structure composed of an inner porous matrix surrounded by two external dense layers. This is different from the plywood-like laminated structure of elasmoid fish scales but similar to the structure of osteoderms found in the dermal armour of some reptiles and mammals. Chemical analysis performed using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results revealed similarities between the composition of P. pardalis plates and the elasmoid fish scales of Arapaima gigas. Reduced moduli of P. pardalis plates measured using nanoindentation were also consistent with reported values for A. gigas scales, but further revealed that the dermal plate is an anisotropic and heterogeneous material, similar to many other fish scales and osteoderms. It is postulated that the sandwich-like structure of the dermal plates provides a lightweight and tough protective layer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chitosan solutions as injectable systems for dermal filler applications: Rheological characterization and biological evidence.

Science.gov (United States)

Halimi, C; Montembault, A; Guerry, A; Delair, T; Viguier, E; Fulchiron, R; David, L

2015-01-01

A new generation of dermal filler for wrinkle filler based on chitosan was compared to current hyaluronic acid-based dermal fillers by using a new rheological performance criterion based on viscosity during injection related to Newtonian viscosity. In addition an in vivo evaluation was performed for preclinical evidence of chitosan use as dermal filler. In this way, biocompatibility and dermis reconstruction was evaluated on a pig model.

Characterization and evolution of dermal filaments from patients with Morgellons disease.

Science.gov (United States)

Middelveen, Marianne J; Mayne, Peter J; Kahn, Douglas G; Stricker, Raphael B

2013-01-01

Morgellons disease is an emerging skin disease characterized by formation of dermal filaments associated with multisystemic symptoms and tick-borne illness. Some clinicians hypothesize that these often colorful dermal filaments are textile fibers, either self-implanted by patients or accidentally adhering to lesions, and conclude that patients with this disease have delusions of infestation. We present histological observations and electron microscopic imaging from representative Morgellons disease samples revealing that dermal filaments in these cases are keratin and collagen in composition and result from proliferation and activation of keratinocytes and fibroblasts in the epidermis. Spirochetes were detected in the dermatological specimens from our study patients, providing evidence that Morgellons disease is associated with an infectious process.

Correlation of Hypoxia and Pro-senescence Protein Expression in Green Sea Turtle (Chelonia mydas Lung Epithelial and Dermal Fibroblast Cell Culture

Directory of Open Access Journals (Sweden)

Anggraini Barlian

2018-03-01

Full Text Available Recent studies have shown hypoxia-induced gene expression correlated with cellular senescence. HIF-1α (hypoxia-inducible factor 1-alpha, p53, and pRB were induced under hypoxia and correlated with cellular senescence. The localization and expression of HIF-1α, p53, and pRB in Chelonia mydas lung epithelial and dermal fibroblast cell cultures were analyzed under normoxic and hypoxic conditions (at 4 and 24 hours. Human dermal fibroblast was used for comparison purposes. Protein localization was analyzed with immunocytochemistry, while protein expression was analyzed with the Western blot and enhanced chemiluminescence (ECL method. HIF-1α, p53, and pRB were localized in the nuclei of the C. mydas cell cultures treated with hypoxia. The C. mydas lung epithelial cell cultures had a higher increase of HIF-1α expression than the human dermal fibroblast cell culture. The hypoxic conditions did not affect p53 expression significantly in C. mydas lung epithelial and dermal fibroblast cell cultures. Meanwhile, pRB expression changed significantly under hypoxia in the C. mydas dermal fibroblast cells. Expression of p53 and pRB in the human cell cultures was higher than in the C. mydas cell cultures. This research suggests that C. mydas and human cell cultures have different pro-senescence protein expression responses under hypoxic conditions.

Linking existing in vitro dermal absorption data to physicochemical properties: Contribution to the design of a weight-of-evidence approach for the safety evaluation of cosmetic ingredients with low dermal bioavailability.

Science.gov (United States)

Ates, Gamze; Steinmetz, Fabian P; Doktorova, Tatyana Yordanova; Madden, Judith C; Rogiers, Vera

2016-04-01

To characterize the risk of cosmetic ingredients when threshold toxicity is assumed, often the "margin of safety" (MoS) is calculated. This uncertainty factor is based on the systemic no observable (adverse) effect level (NO(A)EL) which can be derived from in vivo repeated dose toxicity studies. As in vivo studies for the purpose of the cosmetic legislation are no longer allowed in Europe and a validated in vitro alternative is not yet available, it is no longer possible to derive a NO(A)EL value for a new cosmetic ingredient. Alternatively, cosmetic ingredients with a low dermal bioavailability might not need repeated dose data, as internal exposure will be minimal and systemic toxicity might not be an issue. This study shows the possibility of identifying compounds suspected to have a low dermal bioavailability based on their physicochemical properties (molecular weight, melting point, topological polar surface area and log P) and their in vitro dermal absorption data. Although performed on a limited number of compounds, the study suggests a strategic opportunity to support the safety assessor's reasoning to omit a MoS calculation and to focus more on local toxicity and mutagenicity/genotoxicity for ingredients for which limited systemic exposure is to be expected. Copyright © 2016 Elsevier Inc. All rights reserved.

Tetrabromobisphenol A In vitro Dermal Absopriton Data

Data.gov (United States)

U.S. Environmental Protection Agency — In vitro dermal absorption data of tetrabromobisphenol A using human cadaver and rat skin. This dataset is associated with the following publication: Knudsen, G., M....

Dynamic interactions between dermal macrophages and Staphylococcus aureus.

Science.gov (United States)

Feuerstein, Reinhild; Kolter, Julia; Henneke, Philipp

2017-01-01

The dermis, a major reservoir of immune cells in immediate vicinity to the colonizing skin microflora, serves as an important site of host-pathogen interactions. Macrophages (Mϕ) are the most frequent resident immune cell type in the dermis. They protect the host from invasive infections by highly adapted bacteria, such as staphylococci via pattern recognition of bacterial effectors, phagocytosis, and recruitment of other myeloid cells from the blood. Already under homeostatic conditions, the dermal Mϕ population receives a dynamic input of monocytes invading from the bloodstream. This quantitative renewal is promoted further at the beginning of life, when prenatally seeded cells are rapidly replaced and in healing phases after injuries or infections. Here, we discuss the potential implications of the dynamic dermal Mϕ biology on the establishment and maintenance of immunity against Staphylococcus aureus, which can either be a harmless colonizer or an invasive pathogen. The understanding of the heterogeneity of the "mature" dermal Mϕ compartment driven both by the influx of differentiating monocytes and by a bone marrow-independent Mϕ persistence and expansion may help to explain failing immunity and immunopathology originating from the skin, the important interface between host and environment. © Society for Leukocyte Biology.

Inhalational and dermal exposures during spray application of biocides.

Science.gov (United States)

Berger-Preiss, Edith; Boehncke, Andrea; Könnecker, Gustav; Mangelsdorf, Inge; Holthenrich, Dagmar; Koch, Wolfgang

2005-01-01

Data on inhalational and potential dermal exposures during spray application of liquid biocidal products were generated. On the one hand, model experiments with different spraying devices using fluorescent tracers were carried out to investigate the influence of parameters relevant to the exposure (e.g. spraying equipment, nozzle size, direction of application). On the other hand, measurements were performed at selected workplaces (during disinfection operations in food and feed areas; pest control operations for private, public and veterinary hygiene; wood protection and antifouling applications) after application of biocidal products such as Empire 20, Responsar SC, Omexan-forte, Actellic, Perma-forte; Fendona SC, Pyrethrum mist; CBM 8, Aldekol Des 03, TAD CID, Basileum, Basilit. The measurements taken in the model rooms demonstrated dependence of the inhalation exposure on the type of spraying device used, in the following order: "spraying with low pressure" < "airless spraying" < "fogging" indicating that the particle diameter of the released spray droplets is the most important parameter. In addition inhalation exposure was lowest when the spraying direction was downward. Also for the potential dermal exposure, the spraying direction was of particular importance: overhead spraying caused the highest contamination of body surfaces. The data of inhalational and potential dermal exposures gained through workplace measurements showed considerable variation. During spraying procedures with low-pressure equipments, dose rates of active substances inhaled by the operators ranged from 7 to 230 microg active substance (a.s.)/h. An increase in inhaled dose rates (6-33 mg a.s./h) was observed after use of high application volumes/time unit during wood protection applications indoors. Spraying in the veterinary sector using medium-pressure sprayers led to inhaled dose rates between 2 and 24mga.s./h. The highest inhaled dose rates were measured during fogging (114 mg a

Use of dermal fat graft for augmentation of the labia majora.

Science.gov (United States)

Salgado, Christopher J; Tang, Jennifer C; Desrosiers, Arthur E

2012-02-01

Dermal fat grafts have been utilized in plastic surgery for both reconstructive and aesthetic purposes of the face, breast, and body. There are multiple reports in the literature on the male phallus augmentation with the use of dermal fat grafts. Few reports describe female genitalia aesthetic surgery, in particular rejuvenation of the labia majora. In this report we describe an indication and use of autologous dermal fat graft for labia majora augmentation in a patient with loss of tone and volume in the labia majora. We found that this procedure is an option for labia majora augmentation and provides a stable result in volume-restoration. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

In vivo degradation of processed dermal sheep collagen evaluated with transmission electron microscopy

NARCIS (Netherlands)

van Wachem, P.B.; van Luyn, M.J.A.; Nieuwenhuis, P.; Koerten, H.K.; Olde damink, L.H.H.; Olde-Damink, L.; ten Hoopen, Hermina W.M.; Feijen, Jan

1991-01-01

The in vivo degradation of hexamethylenediisocyanate-tanned dermal sheep collagen was studied with transmission electron microscopy. Discs of hexamethylenediisocyanate-tanned dermal sheep collagen were subcutaneously implanted in rats. Both an intra- and an extracellular route of degradation could

Age-related changes in dermal fiber-like structures in facial cheeks.

Science.gov (United States)

Mizukoshi, K; Hirayama, K

2017-08-01

Despite recent progress in non-invasive measurement methods, such as in vivo laser confocal microscopy (CLSM), it is difficult to quantitatively measure age-related changes in dermal fibrous structures in the face using these methods and qualitative characteristics. We used characteristics extracted from the analysis of CLSM images to quantitatively investigate the effects of aging on dermal fibrous structures in the face. CLSM images of dermal fibrous structures were obtained from 90 Japanese females, ranging in age from 20 to 60 years. The feature values of CLSM images were extracted using image analysis methods, such as short-line segment-matching processing and spatial frequency analysis. The qualitative characteristics of the dermal fibrous structures in the CLSM images were obtained by principal component analysis (PCA) of these feature values. The fibrous structures were scored on the basis of qualitative characteristics and then age-related changes in the scores among the subjects were quantitatively evaluated. The PCA results showed that there were two characteristics in the images of fibrous structures: clearness and directionality. The clearness of fibrous structures decreased and directionality isotropy increased with age. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Assessment of dermal exposure to chemicals

NARCIS (Netherlands)

Hemmen, J.J. van; Brouwer, D.H.

1995-01-01

The methods for the dermal exposure assessment vary in their complexity and are in some sense complementary to each other. The most easy-to-use methods involve a pseudo-skin-approach, such as gloves and removal by washing. In some cases generic modelling appears to be possible. The experimental

Cleft Palate Fistula Closure Utilizing Acellular Dermal Matrix

Directory of Open Access Journals (Sweden)

Omri Emodi, DMD

2018-03-01

Full Text Available Summary:. Fistulas represent failure of cleft palate repair. Secondary and tertiary fistula repair is challenging, with high recurrence rates. In the present retrospective study, we review the efficacy of using acellular dermal matrix as an interposition layer for cleft palate fistula closure in 20 consecutive patients between 2013 and 2016. Complete fistula closure was obtained in 16 patients; 1 patient had asymptomatic recurrent fistula; 2 patients had partial closure with reduction of fistula size and minimal nasal regurgitation; 1 patient developed a recurrent fistula without changes in symptoms (success rate of 85%. We conclude that utilizing acellular dermal matrix for cleft palate fistula repair is safe and simple with a high success rate.

Cleft Palate Fistula Closure Utilizing Acellular Dermal Matrix.

Science.gov (United States)

Emodi, Omri; Ginini, Jiriys George; van Aalst, John A; Shilo, Dekel; Naddaf, Raja; Aizenbud, Dror; Rachmiel, Adi

2018-03-01

Fistulas represent failure of cleft palate repair. Secondary and tertiary fistula repair is challenging, with high recurrence rates. In the present retrospective study, we review the efficacy of using acellular dermal matrix as an interposition layer for cleft palate fistula closure in 20 consecutive patients between 2013 and 2016. Complete fistula closure was obtained in 16 patients; 1 patient had asymptomatic recurrent fistula; 2 patients had partial closure with reduction of fistula size and minimal nasal regurgitation; 1 patient developed a recurrent fistula without changes in symptoms (success rate of 85%). We conclude that utilizing acellular dermal matrix for cleft palate fistula repair is safe and simple with a high success rate.

Assessment of dermal exposure to bitumen condensate among road paving and mastic crews with an observational method

NARCIS (Netherlands)

Agostini, M.; Fransman, W.; Vocht, F.D.; Joode, B.V.W.D.; Kromhout, H.

2011-01-01

Objective: To assess dermal exposure to bitumen condensate among road pavers and indoor mastic workers in multiple crews using a semi-quantitative observational method [DeRmal Exposure Assessment Method (DREAM)].Methods: Two skilled observers assessed dermal exposure to bitumen condensate among 85

Systemic and intestinal levels of factor XIII-A

DEFF Research Database (Denmark)

Søndergaard, Christoffer; Kvist, Peter Helding; Seidelin, Jakob Benedict

2016-01-01

the loss of both FXIII antigen and activity during active disease. CONCLUSIONS: Intestinal inflammation in UC induces loss of M2 macrophages with subsequent loss of FXIII-A synthesis. The loss of cellular FXIII-A may impact migration and phagocytosis, and hence limit pathogen eradication in UC....

Liposome-containing Hibiscus sabdariffa calyx extract formulations with increased antioxidant activity, improved dermal penetration and reduced dermal toxicity.

Science.gov (United States)

Pinsuwan, Sirirat; Amnuaikit, Thanaporn; Ungphaiboon, Suwipa; Itharat, Arunporn

2010-12-01

Hibiscus sabdariffa Linn, or Roselle, is a medicinal plant used extensively in traditional Thai medicine since ancient times. The extracts of Roselle calyces possess antioxidant activity and have potential for development as active ingredients in cosmetic products. However the limitations of using Roselle extracts in cosmetics are its low skin permeation and dermal irritation. Liposome technology is an obvious approach that might overcome these problems. Liposome formulations of standardized Roselle extracts were developed with various lipid components. The formulation showing the highest entrapment efficiency was selected for stability, skin permeation and dermal irritability studies. The liposome formulation with the highest entrapment efficiency (83%) and smalôlest particle size (332 mm) was formulated with phosphatidylcholine from soybean (SPC): Tween 80: deoxycholic acid (DA); 84:16:2.5 weight ratio, total lipid of 200 g/mL and 10% w/v Roselle extract in final liposomal preparation. This liposome formulation was found to be stable after storage at 4 degrees C, protected from light, for 2 months. The in vitro skin permeation studies, using freshly excised pig skin and modified Franz-diffusion cells, showed that the liposome formulation was able to considerably increased the rate of permeation of active compounds in Roselle extracts compared to the Roselle extract solution. The in vivo dermal irritability testing on rabbit skin showed that the liposome formulation dramatically decreased skin irritability compared to the unformulated extract. These results showed that the liposomes containing Roselle extracts had good stability, high entrapment efficacy, increased skin permeation and low skin irritation.

A systematic review of acelluar dermal matrices in head and neck reconstruction.

Science.gov (United States)

Shridharani, Sachin M; Tufaro, Anthony P

2012-11-01

The use of acellular dermal matrices has been well described in the scientific literature since the early 1990 s and has been utilized for multiple applications in the head and neck for both aesthetic and reconstructive efforts. After systematically searching the PubMed database and following further refinement (based on the authors' inclusion and exclusion criteria), the authors identified 30 studies that provided information about patients who had undergone head and neck reconstruction with the use of acellular dermal matrix. Studies had to report quantifiable objective results in patients who were older than 1 year and younger than 90 years. The authors excluded single case reports, studies with fewer than 10 patients, and studies not published in English. The optimal material used as an implant for reconstruction possesses the following properties: facilitation of vascular ingrowth, decreased propensity to incite inflammation, biologic inertness, resistance to infection, and ease of handling. Acellular dermal matrix possesses many of these properties and is utilized in reconstructing nasal soft tissue and skeletal support, tympanic membrane, periorbital soft tissue, extraoral and intraoral defects, oropharyngeal defects, dura mater, and soft-tissue deficits from parotidectomy. Furthermore, it is used to assist in preventing Frey syndrome following parotidectomy and surgical treatment of facial paralysis. Use of acellular dermal matrix for head and neck reconstruction has expanded exponentially and is validated in many studies. Further prospective randomized control trials are warranted to further investigate the efficacy of acellular dermal matrix in head and neck reconstruction.

Labeled chloroquine analog in diagnosis of ocular and dermal melanomas

International Nuclear Information System (INIS)

Beierwaltes, W.H.

1974-01-01

On the basis of the melanin-specific properties of chloroquine, an 125 I-labeled chloroquine analog (NM-113) was synthesized for use in the diagnosis of ocular and dermal melanomas. The limitations and indications for the use of NM-113 in the diagnosis of dermal melanomas are summarized, and its efficiency in the diagnosis of ocular melanomas is discussed. The low probability of side effects (radiation effects) on the retina from a diagnostic dose of 2 m Ci (46 rads) is mentioned. (U.S.)

The Effects of Chronological Age on the Cellular Mechanics of Human Dermal Fibroblasts

Science.gov (United States)

Pan, Z.; Hung, V.; Kambhampati, S.; Ge, S. R.; Rafailovich, M.; Ghosh, K.; Clark, R.; Liu, Y. J.; Nakamura, T.; Shu, X. Z.; Prestwich, G.

2006-03-01

It is often observed that older people display diminished wound healing abilities. Understanding of this phenomenon is important for many in vivo applications of tissue engineering. In this study, the cell mechanics of dermal fibroblasts from 25, 40 and 84 years old female subjects were compared. These cells were cultured on functionalized hyaluronic acid hydrogel substrates which emulated physiological conditions in dermal tissue. The deformation of the substrate caused by cellular traction forces was detected by tracing the displacement of fluorescent beads embedded in the substrate using Digital Image Speckle Correlation. Then cellular traction forces were quantitatively determined by Finite Element Method in a linear elastic model with a high spatial resolution. These results were correlated with auxiliary measurements of substrate modulus, cell modulus and migration. We found that with increasing age, the magnitude of the cellular traction forces diminished. Similarly, the ability of the cells to adapt to changes in the mechanical properties of their environment and migrate was also impaired. The interrelationship between these factors and wound healing will be discussed. This work is supported by NSF- MRSEC program.

Harmonization of future needs for dermal exposure assessment and modeling : a workshop report

NARCIS (Netherlands)

Marquart, H.; Maidment, S.; Mcclaflin, J.L.; Fehrenbacher, M.C.

2001-01-01

Dermal exposure assessment and modeling is still in early phases of development. This article presents the results of a workshop organized to harmonize the future needs in this field. Methods for dermal exposure assessment either assess the mass of contaminant that is transferred to the skin, or the

SIRT-1 regulates TGF-β-induced dermal fibroblast migration via modulation of Cyr61 expression.

Science.gov (United States)

Kwon, Eun-Jeong; Park, Eun-Jung; Yu, Hyeran; Huh, Jung-Sik; Kim, Jinseok; Cho, Moonjae

2018-05-01

SIRT1 is a NAD-dependent protein deacetylase that participates in cellular regulation. The increased migration of fibroblasts is an important phenotype in fibroblast activation. The role of SIRT1 in cell migration remains controversial as to whether SIRT1 acts as an activator or suppressor of cell migration. Therefore, we have established the role of SIRT1 in the migration of human dermal fibroblasts and explored targets of SIRT1 during dermal fibroblast migration. SIRT1 and Cyr61 were expressed in human dermal fibroblasts and the stimulation with TGF-β further induced their expression. Treatment with resveratrol (RSV), a SIRT1 agonist, or overexpression of SIRT1 also promoted the expression Cyr61 in human dermal fibroblasts, whereas the inhibition of SIRT1 activity by nicotinamide or knockdown of SIRT1 decreased the level of Cyr61, as well as TGF-β or RSV-induced Cyr61 expression. Blocking of ERK signaling by PD98509 reduced the expression of Cyr61 induced by TGF-β or RSV. TGF-β, RSV, or SIRT1 overexpression enhanced β-catenin as well as Cyr61 expression. This stimulation was reduced by the Wnt inhibitor XAV939. RSV increased migration and nicotinamide attenuated RSV-induced migration of human dermal fibroblasts. Furthermore, SIRT1 overexpression promoted cell migration, whereas blocking Cyr61 attenuated SIRT1-stimulated migration of human dermal fibroblasts. SIRT1 increased cell migration by stimulating Cyr61 expression and the ERK and Wnt/β-catenin signaling. SIRT1-induced Cyr61 activity is very important for human dermal fibroblasts migration.

Characterization and evolution of dermal filaments from patients with Morgellons disease

OpenAIRE

Middelveen, Marianne J; Mayne, Peter J; Kahn, Douglas G; Stricker, Raphael B

2013-01-01

Marianne J Middelveen,1 Peter J Mayne,1 Douglas G Kahn,2 Raphael B Stricker11International Lyme and Associated Diseases Society, Bethesda, MD, USA; 2Department of Pathology, Olive View–UCLA Medical Center, Sylmar, CA, USAAbstract: Morgellons disease is an emerging skin disease characterized by formation of dermal filaments associated with multisystemic symptoms and tick-borne illness. Some clinicians hypothesize that these often colorful dermal filaments are textile fibers, either s...

Cross-finger dermal pocketing to augment venous outflow for distal fingertip replantation.

Science.gov (United States)

Tan, Valerie H; Murugan, Arul; Foo, Tun-Lin; Puhaindran, Mark E

2014-09-01

Venous anastomosis in distal fingertip replantations is not always possible, and venous congestion is recognized as a potential cause of failure. Methods previously described to address this problem include amputate deepithelization and dermal pocketing postarterial anastomosis to augment venous outflow. However, attachment of the digit to the palm or abdomen resulted in finger stiffness. We describe a modification of the previous methods by utilizing dermal flaps raised from the adjacent digit in the form of a cross-finger flap. The key differences are the partial deepithelization of the replanted fingertip and subsequent replacement of the dermal flap to the donor digit to minimize donor site morbidity. During the period where the 2 digits are attached, interphalangeal joint mobilization is permitted to maintain joint mobility.

Complications caused by injection of dermal filler in Danish patients

DEFF Research Database (Denmark)

Uth, Charlotte Caspara; Elberg, Jens Jørgen; Zachariae, Claus

2016-01-01

Background: The usage of dermal fillers has increased significantly in recent years. Soft tissue augmentation with fillers helps to diminish the facial lines and to restore volume and fullness in the face at a relatively low cost. With the increasing number of treatments, the number of complicati......Background: The usage of dermal fillers has increased significantly in recent years. Soft tissue augmentation with fillers helps to diminish the facial lines and to restore volume and fullness in the face at a relatively low cost. With the increasing number of treatments, the number...

DERMAL, ORAL, AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

Science.gov (United States)

Methyl tertiary butyl ether (MTBE), a gasoline additive, used to increase octane and reduce carbon monoxide emissions and ozone precursors has contaminated drinking water leading to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhalation ki...

Altered Dermal Fibroblasts in Systemic Sclerosis Display Podoplanin and CD90.

Science.gov (United States)

Nazari, Banafsheh; Rice, Lisa M; Stifano, Giuseppina; Barron, Alexander M S; Wang, Yu Mei; Korndorf, Tess; Lee, Jungeun; Bhawan, Jag; Lafyatis, Robert; Browning, Jeffrey L

2016-10-01

Tissue injury triggers the activation and differentiation of multiple cell types to minimize damage and initiate repair processes. In systemic sclerosis, these repair processes appear to run unchecked, leading to aberrant remodeling and fibrosis of the skin and multiple internal organs, yet the fundamental pathological defect remains unknown. We describe herein a transition wherein the abundant CD34(+) dermal fibroblasts present in healthy human skin disappear in the skin of systemic sclerosis patients, and CD34(-), podoplanin(+), and CD90(+) fibroblasts appear. This transition is limited to the upper dermis in several inflammatory skin diseases, yet in systemic sclerosis, it can occur in all regions of the dermis. In vitro, primary dermal fibroblasts readily express podoplanin in response to the inflammatory stimuli tumor necrosis factor and IL-1β. Furthermore, we show that on acute skin injury in both human and murine settings, this transition occurs quickly, consistent with a response to inflammatory signaling. Transitioned fibroblasts partially resemble the cells that form the reticular networks in organized lymphoid tissues, potentially linking two areas of fibroblast research. These results allow for the visualization and quantification of a basic stage of fibroblast differentiation in inflammatory and fibrotic diseases in the skin. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

The Dermal Apron Technique for Immediate Implant Socket Management: A Novel Technique.

Science.gov (United States)

Levin, Barry P

2016-01-01

With immediate implant placement and provisionalization (IIP) in the esthetic zone, measures to counter hard and soft tissue loss are frequently necessary. To reduce the morbidity associated with bone and connective tissue procurement, various exogenous materials are utilized. The "Dermal Apron Technique" presented in this article demonstrates the use of a composite bone particulate (allograft/xenograft) plus a dermal allograft, adapted around screw-retained temporary crowns and secured within a subperiosteal pouch. The purpose is to augment the thickness of peri-implant mucosa for the purpose of preserving ridge dimensions and preventing mucosal recession. Controlled studies are required to further support its use. Clinical significance: Soft tissue health and harmony are critical for successful implant therapy in the esthetic regions of the dentition. Often, autogenous soft tissue grafts are used to augment peri-implant soft tissues. The Dermal Apron Technique is a method, that in specific situations, obviates the need for autogenous grafting. This reduces treatment time and morbidity associated with procurement of these grafts. The Dermal Apron Technique is used simultaneous with immediate placement and provisionalization and can improve long-term esthetic outcomes for patients. © 2016 Wiley Periodicals, Inc.

Dermal exposure to monoterpenes during wood work.

Science.gov (United States)

Eriksson, Kare; Wiklund, Leif

2004-06-01

The dermal exposure to the suspected allergenic monoterpenes [small alpha]-pinene, [small beta]-pinene and [capital Delta](3)-carene was assessed with a patch sampling technique. The patch used was made of activated charcoal sandwiched between two layers of cotton cloth. Patches were fastened at 12 different spots on a sampling overall and at the front of a cap to estimate the potential exposure of the body. Fastening two patches on a cotton glove, one patch representing the dorsal side and one patch representing the palm of the hand respectively, assessed the exposure on the hands. Sampling was carried out during collecting of pine and spruce boards in sawmills and during sawing of pine wood pieces in joinery shops respectively. The potential dermal exposure of the total body was 29.0-1 890 mg h(-1) with a geometric mean (GM) of 238 mg h(-1) during sawing. During collecting the GM was estimated to 100 mg h(-1) with a range of 12.2-959 mg h(-1). The hands had a mean exposure of 9.24 mg h(-1) during sawing and 3.25 mg h(-1) during collecting respectively. The good correlation between the mass of contamination on the individual body parts and the potential body exposure indicates that sampling can be performed on one body part to give a good estimation of the potential body exposure. Monoterpenes were detected at patches fastened underneath the protective clothing indicating a contamination of the skin of the worker. The patch used may overestimate the dermal exposure.

DERMAL, ORAL AND INHALATION PHARMACOKINETICS OF METHYL TERTIARY-BUTYL ETHER (MTBE) IN HUMAN VOLUNTEERS

Science.gov (United States)

Methyl tertiary butyl ether (MTBE), a gasoline additive used to increase octane and reduce carbon monoxide emissions and ozone precursors, has contaminated drinking water and can lead to exposure by oral, inhalation, and dermal routes. To determine its dermal, oral, and inhal...

The use of dermal autograft as an adjunct to breast reconstruction with tissue expanders.

Science.gov (United States)

Rinker, Brian

2012-12-01

Acellular dermal matrices are commonly used in breast reconstruction but add cost to the procedure and have been associated with complications. Dermal autograft may represent a useful alternative to matrices. Sixteen patients (26 breasts) underwent breast reconstruction using tissue expanders and dermal autograft. Their ages ranged from 41 to 66 years (median, 51 years). Autografts were harvested by wide excision of preexisting abdominal scars. Demographic data, clinical history, and harvest and preparation time were recorded. The initial fill volume, number of expansions, and complications were recorded and compared with published data for acellular dermal matrix-assisted reconstruction. Patients rated their satisfaction with scar appearance on a seven-point scale. Follow-up ranged from 6 to 16 months (mean, 10 months). Three patients were smokers. Mean body mass index was 30.5 (range, 19.1 to 48.8). Three patients received chemotherapy between reconstructive stages, and none required irradiation. The mean time of autograft harvest was 38 minutes, the mean initial fill was 190 cc, and the average number of expansions was 3.5. There were no implant losses. There were three minor complications (19 percent). Initial expander fill, number of expansions, and complication rate were equivalent to historical values for matrix-assisted breast reconstruction. Fourteen of 16 patients (88 percent) were "very satisfied" with their scars. The use of dermal autograft in tissue expander breast reconstruction offers the advantages of acellular dermal matrix, without the associated expense. The technique adds minimally to the operative time and morbidity and is associated with a low complication rate. Therapeutic, IV.

Pigmentation and dermal conservative effects of the astonishing ...

African Journals Online (AJOL)

Background: The preference for a fairer skin-tone has become a common trend ... to evaluate the potent dermal protective effect of the two seaweeds Sargassum ... Extracts with potent melanocytotoxicity were formulated into cosmetic cream ...

Disposition of 2,4-dichlorophenoxyacetic acid dimethylamine by Fischer 344 rats dosed orally and dermally

International Nuclear Information System (INIS)

Pelletier, O.; Ritter, L.; Caron, J.; Somers, D.

1989-01-01

The dimethylamine salt of 14C-ring-labeled 2,4-D was administered to Fischer 344 rats orally (1 and 0.4 mg/kg body weight) and dermally (10 mg/kg body weight). Absorption, distribution, and elimination were determined from 14C-labeled 2,4-D in blood, tissues, and excreta. Quantitatively, most of the orally administered dose (94-96%) became systemically available within 6 h. Following dermal administration 10% of the dose became systemically available over 72 h. However, peak concentrations in blood and kidneys were achieved within 30 min of dosing by either route. By 1.5 h after dosing, 2,4-D concentrations in blood, muscle, liver, and kidneys had decreased in both the orally dosed and dermally dosed animals. Between 2 and 8 h, the blood, muscle, liver and kidney concentrations in dermally dosed animals maintained a plateau while urinary excretion increased, presumably due to continued absorption of 2,4-D from the skin. The concentrations in orally dosed animals continued to decrease. Following 7 h of dermal exposure, skin cleansing removed about 63% of the applied dose; about 17% of the applied dose remained at the site of dermal dosing. At 8 h, 2,4-D concentrations in blood, muscle, liver, and kidneys of dermally dosed animals began to decrease, most likely a result of the removal of the reservoir on the skin. However, 2,4-D continued to be absorbed from skin site, resulting in a slower decline of the 2,4-D concentrations in these tissues over remainder of the 72-h study period. By comparison, in animals that had been orally dosed, the absorbed dose was almost completely excreted within 24 h

Increased dermal mast cell prevalence and susceptibility to development of basal cell carcinoma in humans

DEFF Research Database (Denmark)

Grimbaldeston, Michele A; Skov, Lone; Finlay-Jones, John J

2002-01-01

eliminate them. Studies in a range of inbred mouse strains as well as mast cell-depleted mice reconstituted with mast cell precursors support a functional link between histamine-staining dermal mast cells and the extent of susceptibility to UVB-induced systemic immunomodulation. Humans, like mouse strains......, display variations in dermal mast cell prevalence. In a study of Danish and South Australian BCC patients and control subjects, one 4-mm punch biopsy of non-sun-exposed buttock skin was sampled from each participant. This skin site was investigated to avoid any changes in mast cell prevalence caused...... by sun exposure. Two sections (4 microm) per biopsy were immunohistochemically stained for detection of histamine-containing dermal mast cells. Computer-generated image analysis evaluated dermal mast cell prevalence in both sections by quantifying the total number of mast cells according to the total...

Quantification of dermal exposure to nanoparticles from solid nanocomposites by using single particle ICP-MS

DEFF Research Database (Denmark)

Mackevica, Aiga; Olsson, Mikael Emil; Hansen, Steffen Foss

2016-01-01

, optical or photocatalytical properties. There is a lot of research focusing on effects exerted by nanoparticles, but the knowledge concerning release and subsequential exposure to nanoparticles is very limited, and information regarding potential dermal exposure from nanomaterial containing solid articles...... and characterization. In this study, we have investigated the potential dermal exposure to three different types of nano-enabled consumer products: Ag-containing keyboard covers, TiO2 coated ceramic tiles, and wood painted with CuO containing paint. The potential for dermal transfer from the aforementioned surfaces...

Chest wall reconstruction with acellular dermal matrix (Strattice™) and a TRAM flap

DEFF Research Database (Denmark)

Brunbjerg, Mette Eline; Juhl, Alexander Andersen; Damsgaard, Tine Engberg

2014-01-01

Mette Eline Brunbjerg, Alexander Andersen Juhl, Tine E. Damsgaard. "Chest wall reconstruction with acellular dermal matrix (Strattice™) and a TRAM flap.” Acta Oncol. 2013 Jun;52(5):1052-4. Epub 2012 Oct 24. PMID: 23095144......Mette Eline Brunbjerg, Alexander Andersen Juhl, Tine E. Damsgaard. "Chest wall reconstruction with acellular dermal matrix (Strattice™) and a TRAM flap.” Acta Oncol. 2013 Jun;52(5):1052-4. Epub 2012 Oct 24. PMID: 23095144...

Dermal changes in superficial basal cell carcinoma, melanoma in situ and actinic keratosis and their implications

Science.gov (United States)

Kazlouskaya, Viktoryia; Malhotra, Saurabh; Navarro, Raquel; Wu, Karen Nguyen; Shvartsbeyn, Marianna; Shengli, Chen; Gui, Jiang; Elston, Dirk M.

2018-01-01

Background Basal cell carcinoma (BCC) has a characteristic stroma, but less is known about the dermal characteristics associated with melanoma in situ (MIS) and actinic keratosis (AK). Materials and methods Dermal changes were studied in 301 specimens of AK, BCC and MIS. Subsequently, blinded images of dermal changes from 90 randomly selected cases of those entities were used to assess the predictive value of the dermal changes. Agreement with the final diagnosis was calculated using kappa coefficient (κ). Results Fibromyxoid stroma was present in 82% of BCC cases; fibrous stroma was seen in 25% of BCC, 58% of MIS and 35.6% of AK specimens (p <0.05). A lichenoid inflammatory infiltrate was frequently associated with AK and a perifollicular infiltrate with periadnexal fibrosis with MIS. Blinded evaluation of images of the dermal changes associated with the tumors yielded the correct diagnosis in (54.4, 41.1 and 27.8%; average 41.2%) by the three appraisers. Coefficient of agreement in blinded imaged evaluation with the actual diagnosis was higher in the BCC and MIS compared with AK (κ = 0.37, p = 0.0001; κ = 0.2, p = 0.0005 and κ = −0.06, p = 0.84, respectively). Conclusion Dermal features may be helpful in predicting the correct diagnosis when tumor is not visible. PMID:24117926

Dermal absorption and urinary elimination of N-methyl-2-pyrrolidone.

Science.gov (United States)

Bader, Michael; Keener, Stephen A; Wrbitzky, Renate

2005-09-01

The dermal absorption of the solvent N-methyl-2-pyrrolidone (NMP) and its elimination in urine was investigated in an experimental study. Seven volunteers were exposed to 1045 mg of liquid NMP under occlusive conditions for 2 h. Urine was collected before, during and up to 72 h after the exposure and analysed for NMP by GC/MS after liquid-liquid extraction. Additionally, the remaining NMP in the pads was determined to estimate the total dermal uptake. The concentration of NMP in urine increased rapidly after beginning of the exposure up to 1 h after the exposure was completed. A peak concentration of 1,836+/-863 microg/l was observed, the half-life in urine was 3.2 h. About 0.5% of the absorbed dose was excreted metabolically unchanged. An average dermal absorption of 5.5 mg cm(-2) h(-1) was calculated. The results of this study show that the percutaneous absorption of NMP may contribute significantly to the overall uptake of the solvent, e.g. in the workplace. Therefore, a biological monitoring of NMP exposed workers is essential for occupational-medical surveillance.

Tricho-odonto-onycho-dermal dysplasia and WNT10A mutations.

Science.gov (United States)

Kantaputra, P; Kaewgahya, M; Jotikasthira, D; Kantaputra, W

2014-04-01

We report on three novel (IVS2+1G>A splice site, c.1066G>T, and c.1039G>T, and one previously reported (c.637G>A) WNT10A mutations in three patients affected with odonto-onycho-dermal dysplasia (OODD; OMIM 275980). OODD is a rare form of autosomal recessive ectodermal dysplasia involving hair, teeth, nails, and skin, characterized by hypodontia (tooth agenesis), smooth tongue with marked reduction of filiform and fungiform papillae, nail dysplasia, dry skin, palmoplantar keratoderma, and hyperhidrosis of palms and soles. The novel IVS+1G>A splice site mutation is predicted to cause significant protein alteration. The other novel mutations we found including c.1066G>T and c.1039G>T are predicted to cause p.Gly356Cys and p.Glu347X, respectively. Barrel-shaped mandibular incisors and severe hypodontia appear to be associated with homozygous or compound heterozygous mutations of WNT10A. The name "tricho-odonto-onycho-dermal dysplasia" is suggested to replace "odonto-onycho-dermal dysplasia" because hair anomalies including hypotrichosis and slow-growing hair have been reported in numerous reported patients with this syndrome. © 2014 Wiley Periodicals, Inc.

Hydrocortisone and triiodothyronine regulate hyaluronate synthesis in a tissue-engineered human dermal equivalent through independent pathways.

Science.gov (United States)

Deshpande, Madhura; Papp, Suzanne; Schaffer, Lana; Pouyani, Tara

2015-02-01

Hydrocortisone (HC) and triiodothyronine (T3) have both been shown to be capable of independently inhibiting hyaluronate (HA, hyaluronic acid) synthesis in a self-assembled human dermal equivalent (human dermal matrix). We sought to investigate the action of these two hormones in concert on extracellular matrix formation and HA inhibition in the tissue engineered human dermal matrix. To this end, neonatal human dermal fibroblasts were cultured in defined serum-free medium for 21 days in the presence of each hormone alone, or in combination, in varying concentrations. Through a process of self-assembly, a substantial dermal extracellular matrix formed that was characterized. The results of these studies demonstrate that combinations of the hormones T3 and hydrocortisone showed significantly higher levels of hyaluronate inhibition as compared to each hormone alone in the human dermal matrix. In order to gain preliminary insight into the genes regulating HA synthesis in this system, a differential gene array analysis was conducted in which the construct prepared in the presence of 200 μg/mL HC and 0.2 nM T3 was compared to the normal construct (0.4 μg/mL HC and 20 pM T3). Using a GLYCOv4 gene chip containing approximately 1260 human genes, we observed differential expression of 131 genes. These data suggest that when these two hormones are used in concert a different mechanism of inhibition prevails and a combination of degradation and inhibition of HA synthesis may be responsible for HA regulation in the human dermal matrix. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

A feeder- and xeno-free human induced pluripotent stem cell line obtained from primary human dermal fibroblasts with epigenetic repression of reprogramming factors expression: GPCCi001-A

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Michał Stefan Lach

2017-04-01

Full Text Available The primary human dermal fibroblasts (PHDFs from breast cancer patient were obtained to generate the human induced pluripotent stem cell line GPCCi001-A via lentiviral transfection. Thus, a modified EF1a-hSTEMCCA-loxP with tetO operator which regulates transgene expression was used. This method takes advantage of epigenetic regulation of transcription and allows for stable silencing of the reprogramming factors in obtained hiPS cells. To increase the potential utility of hiPSCs for clinical applications, they were adapted to feeder- and xeno-free conditions. The pluripotency of GPCCi001-A cell line and ability to differentiate into three germ layers was confirmed.

Functional trade-off between strength and thermal capacity of dermal armor: Insights from girdled lizards.

Science.gov (United States)

Broeckhoven, Chris; du Plessis, Anton; Hui, Cang

2017-10-01

The presence of dermal armor is often unambiguously considered the result of an evolutionary predator-prey arms-race. Recent studies focusing predominantly on osteoderms - mineralized elements embedded in the dermis layer of various extant and extinct vertebrates - have instead proposed that dermal armor might exhibit additional functionalities besides protection. Multiple divergent functionalities could impose conflicting demands on a phenotype, yet, functional trade-offs in dermal armor have rarely been investigated. Here, we use high-resolution micro-computed tomography and voxel-based simulations to test for a trade-off between the strength and thermal capacity of osteoderms using two armored cordylid lizards as model organisms. We demonstrate that high vascularization, associated with improved thermal capacity might limit the strength of osteoderms. These results call for a holistic, cautionary future approach to studies investigating dermal armor, especially those aiming to inspire artificial protective materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sexual dimorphisms in the dermal denticles of the lesser-spotted catshark, Scyliorhinus canicula (Linnaeus, 1758.

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Neil Crooks

Full Text Available The dermal layers of several elasmobranch species have been shown to be sexually dimorphic. Generally, when this occurs the females have thicker dermal layers compared to those of males. This sexual dimorphism has been suggested to occur as a response to male biting during mating. Although male biting as a copulatory behaviour in Scyliorhinus canicula has been widely speculated to occur, only relatively recently has this behaviour been observed. Male S. canicula use their mouths to bite the female's pectoral and caudal fins as part of their pre-copulatory behaviour and to grasp females during copulation. Previous work has shown that female S. canicula have a thicker epidermis compared to that of males. The structure of the dermal denticles in females may also differ from that of males in order to protect against male biting or to provide a greater degree of friction in order to allow the male more purchase. This study reveals that the length, width and density of the dermal denticles of mature male and female S. canicula are sexually dimorphic across the integument in areas where males have been observed to bite and wrap themselves around females (pectoral fin, area posterior to the pectoral fin, caudal fin, and pelvic girdle. No significant differences in the dermal denticle dimensions were found in other body areas examined (head, dorsal skin and caudal peduncle. Sexually dimorphic dermal denticles in mature S. canicula could be a response to male biting/wrapping as part of the copulatory process.

Determinants of dermal exposure relevant for exposure modelling in regulatory risk assessment.

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Marquart, J; Brouwer, D H; Gijsbers, J H J; Links, I H M; Warren, N; van Hemmen, J J

2003-11-01

Risk assessment of chemicals requires assessment of the exposure levels of workers. In the absence of adequate specific measured data, models are often used to estimate exposure levels. For dermal exposure only a few models exist, which are not validated externally. In the scope of a large European research programme, an analysis of potential dermal exposure determinants was made based on the available studies and models and on the expert judgement of the authors of this publication. Only a few potential determinants appear to have been studied in depth. Several studies have included clusters of determinants into vaguely defined parameters, such as 'task' or 'cleaning and maintenance of clothing'. Other studies include several highly correlated parameters, such as 'amount of product handled', 'duration of task' and 'area treated', and separation of these parameters to study their individual influence is not possible. However, based on the available information, a number of determinants could clearly be defined as proven or highly plausible determinants of dermal exposure in one or more exposure situation. This information was combined with expert judgement on the scientific plausibility of the influence of parameters that have not been extensively studied and on the possibilities to gather relevant information during a risk assessment process. The result of this effort is a list of determinants relevant for dermal exposure models in the scope of regulatory risk assessment. The determinants have been divided into the major categories 'substance and product characteristics', 'task done by the worker', 'process technique and equipment', 'exposure control measures', 'worker characteristics and habits' and 'area and situation'. To account for the complex nature of the dermal exposure processes, a further subdivision was made into the three major processes 'direct contact', 'surface contact' and 'deposition'.

Matrix-directed differentiation of human adipose-derived mesenchymal stem cells to dermal-like fibroblasts that produce extracellular matrix.

Science.gov (United States)

Sivan, Unnikrishnan; Jayakumar, K; Krishnan, Lissy K

2016-10-01

Commercially available skin substitutes lack essential non-immune cells for adequate tissue regeneration of non-healing wounds. A tissue-engineered, patient-specific, dermal substitute could be an attractive option for regenerating chronic wounds, for which adipose-derived mesenchymal stem cells (ADMSCs) could become an autologous source. However, ADMSCs are multipotent in nature and may differentiate into adipocytes, osteocytes and chondrocytes in vitro, and may develop into undesirable tissues upon transplantation. Therefore, ADMSCs committed to the fibroblast lineage could be a better option for in vitro or in vivo skin tissue engineering. The objective of this study was to standardize in vitro culture conditions for ADMSCs differentiation into dermal-like fibroblasts which can synthesize extracellular matrix (ECM) proteins. Biomimetic matrix composite, deposited on tissue culture polystyrene (TCPS), and differentiation medium (DM), supplemented with fibroblast-conditioned medium and growth factors, were used as a fibroblast-specific niche (FSN) for cell culture. For controls, ADMSCs were cultured on bare TCPS with either DM or basal medium (BM). Culture of ADMSCs on FSN upregulated the expression of differentiation markers such as fibroblast-specific protein-1 (FSP-1) and a panel of ECM molecules specific to the dermis, such as fibrillin-1, collagen I, collagen IV and elastin. Immunostaining showed the deposition of dermal-specific ECM, which was significantly higher in FSN compared to control. Fibroblasts derived from ADMSCs can synthesize elastin, which is an added advantage for successful skin tissue engineering as compared to fibroblasts from skin biopsy. To obtain rapid differentiation of ADMSCs to dermal-like fibroblasts for regenerative medicine, a matrix-directed differentiation strategy may be employed. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

A dermal model for spray painters, part I : subjective exposure modelling of spray paint deposition

NARCIS (Netherlands)

Brouwer, D.H.; Semple, S.; Marquart, J.; Cherrie, J.W.

2001-01-01

The discriminative power of existing dermal exposure models is limited. Most models only allow occupational hygienists to rank workers between and within workplaces according to broad bands of dermal exposure. No allowance is made for the work practices of different individuals. In this study a

Characterization and evolution of dermal filaments from patients with Morgellons disease

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Middelveen MJ

2013-01-01

Full Text Available Marianne J Middelveen,1 Peter J Mayne,1 Douglas G Kahn,2 Raphael B Stricker11International Lyme and Associated Diseases Society, Bethesda, MD, USA; 2Department of Pathology, Olive View–UCLA Medical Center, Sylmar, CA, USAAbstract: Morgellons disease is an emerging skin disease characterized by formation of dermal filaments associated with multisystemic symptoms and tick-borne illness. Some clinicians hypothesize that these often colorful dermal filaments are textile fibers, either self-implanted by patients or accidentally adhering to lesions, and conclude that patients with this disease have delusions of infestation. We present histological observations and electron microscopic imaging from representative Morgellons disease samples revealing that dermal filaments in these cases are keratin and collagen in composition and result from proliferation and activation of keratinocytes and fibroblasts in the epidermis. Spirochetes were detected in the dermatological specimens from our study patients, providing evidence that Morgellons disease is associated with an infectious process.Keywords: Morgellons disease, digital dermatitis, Lyme disease, Borrelia burgdorferi, spirochetes, keratin, keratinocytes, collagen, fibroblasts

14C-Methylenebisphenylisocyanate (14C-MDI). Study of absorption after single dermal and intradermal administration in rats

International Nuclear Information System (INIS)

Leibold, E.; Hoffmann, H.D.; Hildebrand, B.

1999-01-01

The absorption, distribution and excretion of radioactivity was studied in groups of four male Wistar rats following a single dermal and intradermal administration of 14 C- Methylenebisphenylisocyanate ( 14 C-MDI) at nominal dose levels of 4.0 and 0.4 mg/cm 2 for dermal administration and 0.4 mg/animal for intradermal administration. These dose levels nominally corresponded to 40 and 4.0 mg/animal for dermal administration. Considering the animal weights, dose levels corresponded to about 140 and 14 mg/kg body weight (dermal administration) and 1.4 mg/kg body weight (intradermal administration). In the experiments with dermal administration, animals were exposed for 8 hours and sacrificed 8, 24 or 120 h after beginning of exposure. In the experiment with intradermal administration, animals were sacrificed 120 h after treatment. After dermal administration of 14 C-MDI, mean recoveries of radioactivity from all dose groups were in the range from 97.86 to 108.07% of the total radioactivity administered. Generally, the largest proportion of radioactivity was found at the application site and dressing. The total amount of radioactivity absorbed (including excreta, cage wash, tissues/organs and carcass) increased with increasing sacrifice time. Dermal absorption was very low and quantitatively similar at both dose levels; maximally ca. 0.9 % of the applied radioactivity was absorbed. After intradermal administration of 14 C-MDI, the mean recovery of radioactivity was 100.90 % of the radioactivity administered. The largest proportion of radioactivity was found at the application site. The total amount of radioactivity absorbed (including excreta, cage wash, tissues/organs and carcass) amounted to about 26 % of the radioactivity applied. Irrespective of the mode of administration of 1 4C -MDI, concentrations of radioactivity in tissues and organs generally were below 1 μg Eq/g at 120 h after administration. In summary, the results of this study comparing systemic

Bio-artificial pleura using an autologous dermal fibroblast sheet

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Kanzaki, Masato; Takagi, Ryo; Washio, Kaoru; Kokubo, Mami; Yamato, Masayuki

2017-10-01

Air leaks (ALs) are observed after pulmonary resections, and without proper treatment, can produce severe complications. AL prevention is a critical objective for managing patients after pulmonary resection. This study applied autologous dermal fibroblast sheets (DFS) to close ALs. For sealing ALs in a 44-year-old male human patient with multiple bullae, a 5 × 15-mm section of skin was surgically excised. From this skin specimen, primary dermal fibroblasts were isolated and cultured for 4 weeks to produce DFSs that were harvested after a 10-day culture. ALs were completely sealed using surgical placement of these autologous DFSs. DFS were found to be a durable long-term AL sealant, exhibiting requisite flexibility, elasticity, durability, biocompatibility, and usability, resulting reliable AL closure. DFS should prove to be an extremely useful tissue-engineered pleura substitute.

Analysis of dermal fibroblasts isolated from neonatal and child cleft lip and adult skin: Developmental implications on reconstructive surgery

Czech Academy of Sciences Publication Activity Database

Živicová, V.; Lacina, L.; Mateu, R.; Smetana, K.; Kavkova, R.; Krejci, E.D.; Grim, M.; Kvasilová, A.; Borský, J.; Strnad, Hynek; Hradilová, Miluše; Šáchová, Jana; Kolář, Michal; Dvořánková, B.

2017-01-01

Roč. 40, č. 5 (2017), s. 1323-1334 ISSN 1107-3756 R&D Projects: GA ČR GA13-20293S; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Grant - others:GA MŠk(CZ) LM2015042 Institutional support: RVO:68378050 Keywords : dermal fibroblasts * myofibroblast * neonatal healing * trandforming growth factor-beta * cleft Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 2.341, year: 2016

Rat hair follicle dermal papillae have an extracellular matrix containing basement membrane components

DEFF Research Database (Denmark)

Couchman, J R

1986-01-01

, to be replaced by synthesis of other components including type I and III collagens. It seems likely therefore that the dermal papilla cells in vivo synthesize a basement membrane type of extracellular matrix, although a contribution from epithelial, and in some cases capillary endothelial, cells cannot be ruled......Dermal papillae are small mesenchymally derived zones at the bases of hair follicles which have an important role in hair morphogenesis in the embryo and control of the hair growth cycle in postnatal mammals. The cells of the papilla are enmeshed in a dense extracellular matrix which undergoes...... extensive changes in concert with the hair cycle. Here it is shown that this matrix in anagen pelage follicles of postnatal rats contains an abundance of basement membrane components rather than dermal components such as interstitial collagens. In particular, type IV collagen, laminin, and basement membrane...

Solar-simulated radiation and heat treatment induced metalloproteinase-1 expression in cultured dermal fibroblasts via distinct pathways: implications on reduction of sun-associated aging.

Science.gov (United States)

Lan, Cheng-Che E; Wu, Ching-Shang; Yu, Hsin-Su

2013-12-01

Sun exposure is an important environmental factor affecting human beings. Most knowledge regarding solar aging focused on light radiation (photoaging), and little emphasis has been placed on heat, a factor that is also closely associated with sun exposure. This study was launched to evaluate the effects of simulated solar radiation (SSR) and environmental heat on skin fibroblasts in terms of dermal aging. Cultured human dermal fibroblasts were treated with moderate amount of SSR (200J/cm(2)) and heat (+2°C). The metalloproteinase-1 (MMP-1) expression was used as a surrogate marker for dermal aging and the involved regulatory mechanisms were explored. Both treatment conditions did not affect viability but significantly increased the expressions of MMP-1. In parallel, both treatments increased the intracellular levels of reactive oxygen species (ROS), but the increase induced by SSR is much greater than heat. In contrast, transient receptor potential vanilloid 1 (TRPV-1), the sensor of environmental heat, was upregulated by heat but not SSR treatment. Pretreating fibroblasts with antioxidant abrogated the SSR-induced MMP-1 but has limited effect on heat-induced MMP-1. On the other hand, TRPV-1 antagonist pretreatment reduced heat-induced MMP-1 in fibroblasts but not their SSR-treated counterparts. Both SSR and heat induced MMP-1 expression in dermal fibroblasts but through different pathways. As current strategies for reducing sun-related aging focused on filtering of light and use of antioxidants, future strategies design to reduce solar aging should also incorporate heat-induced aging into consideration. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Evaluation of lymphangiogenesis in acellular dermal matrix

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Mario Cherubino

2014-01-01

Full Text Available Introduction: Much attention has been directed towards understanding the phenomena of angiogenesis and lymphangiogenesis in wound healing. Thanks to the manifold dermal substitute available nowadays, wound treatment has improved greatly. Many studies have been published about angiogenesis and cell invasion in INTEGRA® . On the other hand, the development of the lymphatic network in acellular dermal matrix (ADM is a more obscure matter. In this article, we aim to characterize the different phases of host cell invasion in ADM. Special attention was given to lymphangiogenic aspects. Materials and Methods: Among 57 rats selected to analyse the role of ADM in lymphangiogenesis, we created four groups. We performed an excision procedure on both thighs of these rats: On the left one we did not perform any action except repairing the borders of the wound; while on the right one we used INTEGRA® implant. The excision biopsy was performed at four different times: First group after 7 days, second after 14 days, third after 21 days and fourth after 28 days. For our microscopic evaluation, we used the classical staining technique of haematoxylin and eosin and a semi-quantitative method in order to evaluate cellularity counts. To assess angiogenesis and lymphangiogenesis development we employed PROX-1 Ab and CD31/PECAM for immunohistochemical analysis. Results: We found remarkable wound contraction in defects that healed by secondary intention while minor wound contraction was observed in defects treated with ADM. At day 7, optical microscopy revealed a more plentiful cellularity in the granulation tissue compared with the dermal regeneration matrix. The immunohistochemical process highlighted vascular and lymphatic cells in both groups. After 14 days a high grade of fibrosis was noticeable in the non-treated group. At day 21, both lymphatic and vascular endothelial cells were better developed in the group with a dermal matrix application. At day 28

Monophasic Pulsed 200-μA Current Promotes Galvanotaxis With Polarization of Actin Filament and Integrin α2β1 in Human Dermal Fibroblasts.

Science.gov (United States)

Uemura, Mikiko; Maeshige, Noriaki; Koga, Yuka; Ishikawa-Aoyama, Michiko; Miyoshi, Makoto; Sugimoto, Masaharu; Terashi, Hiroto; Usami, Makoto

2016-01-01

The monophasic pulsed microcurrent is used to promote wound healing, and galvanotaxis regulation has been reported as one of the active mechanisms in the promotion of tissue repair with monophasic pulsed microcurrent. However, the optimum monophasic pulsed microcurrent parameters and intracellular changes caused by the monophasic pulsed microcurrent have not been elucidated in human dermal fibroblasts. The purpose of this study was to investigate the optimum intensity for promoting galvanotaxis and the effects of electrical stimulation on integrin α2β1 and actin filaments in human dermal fibroblasts. Human dermal fibroblasts were treated with the monophasic pulsed microcurrent of 0, 100, 200, or 300 μA for 8 hours, and cell migration and cell viability were measured 24 hours after starting monophasic pulsed microcurrent stimulation. Polarization of integrin α2β1 and lamellipodia formation were detected by immunofluorescent staining 10 minutes after starting monophasic pulsed microcurrent stimulation. The migration toward the cathode was significantly higher in the cells treated with the 200-μA monophasic pulsed microcurrent than in the controls (P microcurrent did not alter the migration ratio. The electrostimulus of 200 μA also promoted integrin α2β1 polarization and lamellipodia formation at the cathode edge (P microcurrent intensity to promote migration toward the cathode, and this intensity could regulate polarization of migration-related intracellular factors in human dermal fibroblasts.

Development and characterization of hyaluronic acid-lysine nanoparticles with potential as innovative dermal filling

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Jaqueline Carneiro

Full Text Available ABSTRACT Skin aging causes changes such as wrinkles and flaccidity leading to a large demand for aesthetic procedures, including dermal filling. A key agent in dermal filling is hyaluronic acid (HA, which is a naturally occurring glycosaminoglycan. However, it is a hydrophilic macromolecule that experiences great difficulty in crossing the skin barrier causing most commercial formulations containing it to be injectable, which in turn brings risks since they involve an invasive technique. In that sense, the aim of this study was to develop and characterize nanoparticles obtained from ionic interaction between HA and lysine (Lys for use as a potential agent of dermal filling for topical application, increasing and improving its applicability and safety. To this end, nanoparticles were obtained by dripping of Lys over HA under magnetic stirring. A nanometric size was confirmed and a suitable surface charge was obtained by zeta potential. Nanoparticles were almost spherical in shape with a smooth surface. Interaction between raw materials for preparing nanoparticles was studied by FTIR and NMR spectroscopy and an ionic interaction was confirmed. These physicochemical features suggest that obtained nanoparticles can be further used as a topical dermal filling.

Review of data on the dermal penetration of mineral oils and waxes used in cosmetic applications.

Science.gov (United States)

Petry, T; Bury, D; Fautz, R; Hauser, M; Huber, B; Markowetz, A; Mishra, S; Rettinger, K; Schuh, W; Teichert, T

2017-10-05

Mineral oils and waxes used in cosmetic products, also referred to as "personal care products" outside the European Union, are mixtures of predominantly saturated hydrocarbons consisting of straight-chain, branched and ring structures with carbon chain lengths greater than C16. They are used in skin and lip care cosmetic products due to their excellent skin tolerance as well as their high protecting and cleansing performance and broad viscosity options. Recently, concerns have been raised regarding potential adverse health effects of mineral oils and waxes from dermal application of cosmetics. In order to be able to assess the risk for the consumer the dermal penetration potential of these ingredients has to be evaluated. The scope and objective of this review are to identify and summarize publicly available literature on the dermal penetration of mineral oils and waxes as used in cosmetic products. For this purpose, a comprehensive literature search was conducted. A total of 13 in vivo (human, animal) and in vitro studies investigating the dermal penetration of mineral oils and waxes has been identified and analysed. The majority of the substances were dermally adsorbed to the stratum corneum and only a minor fraction reached deeper skin layers. Overall, there is no evidence from the various studies that mineral oils and waxes are percutaneously absorbed and become systemically available. Thus, given the absence of dermal uptake, mineral oils and waxes as used in cosmetic products do not present a risk to the health of the consumer. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Dermal morphological changes following salicylic acid peeling and microdermabrasion.

Science.gov (United States)

Abdel-Motaleb, Amira A; Abu-Dief, Eman E; Hussein, Mahmoud Ra

2017-12-01

Microdermabrasion and chemical peeling are popular, inexpensive, and safe methods for treatment of some skin disorders and to rejuvenate skin. To study the alterations of the dermal connective tissue following salicylic acid peeling and microdermabrasion. Twenty patients were participated in our study. All participants underwent facial salicylic acid 30% peel or microdermabrasion (10 cases in each group) weekly for 6 weeks. Punch biopsies were obtained from the clinically normal skin of the right postauricular region 1 week before treatment (control group). Other punch skin biopsies were obtained 1 week after the end of the treatments from the left postauricular area. This region was treated in a similar way to the adjacent lesional skin (treated group). We used routine histological techniques (H&E stain), special stains (Masson trichrome and orcein stains), and image analyzer to study the alterations of the dermal connective tissues. Our study demonstrates variations in the morphological changes between the control and the treated groups, and between chemical peels and microdermabrasion. Both salicylic acid 30% and microdermabrasion were associated with thickened epidermal layer, shallow dermal papillae, dense collagen, and elastic fibers. There was a significant increase among those treated sites vs control regarding epidermal thickness and collagen thickness. Also, there was a highly statistically significant increase among those treated with salicylic acid vs microdermabrasion regarding the epidermal, collagen, and elastin thickness. Both methods stimulate the repair process. The mechanisms underlying these variations are open for further investigations. © 2017 Wiley Periodicals, Inc.

Focal dermal hypoplasia: A rare case report

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Sahana M Srinivas

2015-01-01

Full Text Available Focal dermal hypoplasia (Goltz syndrome is a rare genetic multisystem disorder primarily involving the skin, skeletal system, eyes, and face. We report the case of an eight-month-old female child who presented with multiple hypopigmented atrophic macules along the lines of blaschko, skeletal anomalies, umbilical hernia, developmental delay, hypoplastic nails, syndactyly, and lobster claw deformity characteristic of Goltz syndrome.

Assessment of dermal exposure and histopathologic changes of different sized nano-silver in healthy adult rabbits

Science.gov (United States)

kazem Koohi, Mohammad; Hejazy, Marzie; Asadi, Farzad; Asadian, Peyman

2011-07-01

The purpose of this study is to evaluate the dermal toxicity (Irritation/Corrosion) of three sizes of nanosilver particles (10, 20 and 30 nm) during 3 min, 1 and 4 hours according to the OECD/OCDE guideline Histopathological effects in secondary organs from liver, kidney, heart, spleen and brain 14 day post dermal administration are also reported. 10 and 20 nm Ag nanoparticles treated group showed well defined dermal erythema and oedema. Histopathological findings of 10 and 20 nm (4 hours exposure) on 14-day post dermal administration showed hyperkeratosis, acanthosis, hair-filled follicles and papillomatosis in an irregular epidermis, fibrosis, hyperemia, erythema, intracellular oedema and hyalinisation of collagen in dermis of skin. Liver revealed midzonal and periacinar necrosis, portal mononuclear infiltration, liver fatty change, liver congestion and hyperemic central vein. Splenic red pulp congestion and white pulp hyperreactivity, splenic trabeculae and sinusoidal congestion and hyaline change were found in spleen. Fatty degeneration in some cardiovascular cells and subendocardial hemorrhage without inflammation was perceived. Picnotic appearance of pyramidal neurons in the brain cortex, gliosis and mild perineuronal oedema ischemic cell change and hyperemic meninges was observed in brain. Our research concluded that dermal exposure to lesser sizes of silver nanoparticles is more disastrous than greater ones.

Assessment of dermal exposure and histopathologic changes of different sized nano-silver in healthy adult rabbits

Energy Technology Data Exchange (ETDEWEB)

Koohi, Mohammad kazem; Hejazy, Marzie [Toxicology division, Basic science department, Faculty of Veterinary Medicine, University of Tehran, Qareeb Street, Azadi Av. PO Box: 14155-6453, Tehran (Iran, Islamic Republic of); Asadi, Farzad [Biochemistry division, Basic science department, Faculty of Veterinary Medicine, University of Tehran, Qareeb Street, Azadi Av. PO Box: 14155-6453, Tehran (Iran, Islamic Republic of); Asadian, Peyman, E-mail: mkkoohi@ut.ac.ir [Clinical pathology department, Faculty of Veterinary Medicine, University of Khorramabad (Iran, Islamic Republic of)

2011-07-06

The purpose of this study is to evaluate the dermal toxicity (Irritation/Corrosion) of three sizes of nanosilver particles (10, 20 and 30 nm) during 3 min, 1 and 4 hours according to the OECD/OCDE guideline Histopathological effects in secondary organs from liver, kidney, heart, spleen and brain 14 day post dermal administration are also reported. 10 and 20 nm Ag nanoparticles treated group showed well defined dermal erythema and oedema. Histopathological findings of 10 and 20 nm (4 hours exposure) on 14-day post dermal administration showed hyperkeratosis, acanthosis, hair-filled follicles and papillomatosis in an irregular epidermis, fibrosis, hyperemia, erythema, intracellular oedema and hyalinisation of collagen in dermis of skin. Liver revealed midzonal and periacinar necrosis, portal mononuclear infiltration, liver fatty change, liver congestion and hyperemic central vein. Splenic red pulp congestion and white pulp hyperreactivity, splenic trabeculae and sinusoidal congestion and hyaline change were found in spleen. Fatty degeneration in some cardiovascular cells and subendocardial hemorrhage without inflammation was perceived. Picnotic appearance of pyramidal neurons in the brain cortex, gliosis and mild perineuronal oedema ischemic cell change and hyperemic meninges was observed in brain. Our research concluded that dermal exposure to lesser sizes of silver nanoparticles is more disastrous than greater ones.

Design of an elastin-layered dermal regeneration template.

Science.gov (United States)

Mithieux, Suzanne M; Weiss, Anthony S

2017-04-01

We demonstrate a novel approach for the production of tunable quantities of elastic fibers. We also show that exogenous tropoelastin is rate-limiting for elastin synthesis regardless of the age of the dermal fibroblast donor. Additionally, we provide a strategy to further enhance synthesis by older cells through the application of conditioned media. We show that this approach delivers an elastin layer on one side of the leading dermal repair template for contact with the deep dermis in order to deliver prefabricated elastic fibers to a physiologically appropriate site during subsequent surgery. This system is attractive because it provides for the first time a viable path for sufficient, histologically detectable levels of patient elastin into full-thickness wound sites that have until now lacked this elastic underlayer. The scars of full thickness wounds typically lack elasticity. Elastin is essential for skin elasticity and is enriched in the deep dermis. This paper is significant because it shows that: (1) we can generate elastic fibers in tunable quantities, (2) tropoelastin is the rate-limiting component in elastin synthesis in vitro, (3) we can generate elastin fibers regardless of donor age, (4) we describe a novel approach to further increase the numbers and thickness of elastic fibers for older donors, (5) we improve on Integra Dermal Regeneration Template and generate a new hybrid biomaterial intended to subsequently surgically deliver these elastic fibers, (6) the elastic fiber layer is presented on the side of Integra that is intended for delivery into its physiologically appropriate site i.e. the deep dermis. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Pengujian Toksisitas Akut Oral Dan Dermal pada Biolarvasida Metarhizium anisopliae terhadap Tikus Putih Spraque Dawley

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Deni Zulfiana

2016-03-01

Full Text Available Acute oral and dermal toxicity test against white rats was conducted to determine the toxicity and side effects of bio-larvacide (Metarhizium anisopliae crude extract on humans. In the oral test used a maximum dose 5000 mg/kg and dermal testing used a maximum dose of 2000 mg/kg. Dose treatment and control tested to 5 Spraque Dawley male rats. The results showed that oral treatment with a dose of 5000 mg/kg did not cause mortality and did not cause changes in anatomic pathology of viceral organs. In the dermal treatment with a dose of 2000 mg/kg did not cause mortality and did not cause changes in anatomic pathology of viceral organs. Based on these results LD50 acute oral M. anisopliae biolarvacide above 5000 mg/kg and the acute dermal is above 2000 mg/kg. It was therefore concluded that the formulation of Metarhizium anisopliae biolarvasida classified as not hazardous when used in accordance with the recommendation of the class I (WHO, 2003.

Management of acute complex traumatic wound with a dermal ...

African Journals Online (AJOL)

Background: Acute complex traumatic wounds of the lower limbs are usually ... The recovery is lengthy, and the outcome dependent on the initial injury, the surgical ... of fracture and use of a dermal regeneration template over the fracture site, ...

Skin permeability and pharmacokinetics of diclofenac epolamine administered by dermal patch in Yorkshire-Landrace pigs

Directory of Open Access Journals (Sweden)

Tse S

2012-10-01

Full Text Available Susanna Tse,1 Kendall D Powell,2 Stephen MacLennan,3 Allan R Moorman,4 Craig Paterson,5 Rosonald R Bell11Pfizer Inc, Groton, CT, USA; 2Tandem Labs, Durham, NC, USA; 3BioCryst Pharmaceuticals Inc, Durham, NC, USA; 4Alta Vetta Pharmaceutical Consulting LLC, Durham, NC, USA; 5Salix Pharmaceuticals Inc, Raleigh, NC, USAPurpose: This study compared the pharmacokinetic profile, and systemic and local absorption of diclofenac, following dermal patch application and oral administration in Yorkshire- Landrace pigs.Patients and methods: Twelve anesthetized, female, Yorkshire-Landrace pigs were randomized to receive either the dermal patch (FLECTOR® patch, 10 × 14 cm; Alpharma Pharmaceuticals, a subsidiary of Pfizer Inc, New York, NY or 50 mg oral diclofenac (Voltaren®; Novartis, East Hanover, NJ. Tissue (skin area of 2 × 2 cm and underlying muscles approximately 2–3 cm in depth and blood (10 mL samples were collected at timed intervals up to 11.5 hours after initial patch application or oral administration. The concentrations of diclofenac in plasma, skin, and muscle samples were analyzed using validated ultra performance liquid chromatography tandem mass spectrometric methods.Results: Peak systemic exposure of diclofenac was very low by dermal application compared with oral administration (maximum concentration [Cmax] values of 3.5 vs 9640 ng/mL, respectively. Absorption of diclofenac into underlying muscles beneath the dermal patch was sustained, and followed apparently zero-order kinetics, with the skin serving as a depot with elevated concentrations of diclofenac. Concentrations of diclofenac in muscles beneath the patch application site were similar to corresponding tissues after oral administration (Cmax values of 879 and 1160 ng/mL, respectively. In contrast to the wide tissue distribution of diclofenac after oral administration, dermal patch application resulted in high concentrations of diclofenac only on the treated skin and immediate

Dissolving microneedle patches for dermal vaccination

OpenAIRE

Leone, M.; Monkare, J.T.; Bouwstra, J.A.; Kersten, G.F.A.

2017-01-01

The dermal route is an attractive route for vaccine delivery due to the easy skin accessibility and a dense network of immune cells in the skin. The development of microneedles is crucial to take advantage of the skin immunization and simultaneously to overcome problems related to vaccination by conventional needles (e.g. pain, needle-stick injuries or needle re-use). This review focuses on dissolving microneedles that after penetration into the skin dissolve releasing the encapsulated antige...

Augmentation Phalloplasty With Autologous Dermal Fat Graft in the Treatment of "Small Penis".

Science.gov (United States)

Xu, Lisi; Zhao, Muxin; Chen, Wen; Li, Yangqun; Yang, Zhe; Ma, Ning; Wang, Weixin; Feng, Jun; Liu, Qiyu; Ma, Tong

2016-02-01

Our objective is to report on the efficacy and safety of dermal fat graft in augmentation phalloplasty performed on patients who presented complaining of "small penis," and evaluate the cosmetic and psychological outcomes of it. From April 2010 and January 2015, 23 Chinese adult patients aged 18 to 33 years (average, 23 years) with subjective perception of small penis were included; all who requested an increase in the penile dimension underwent penile elongation (suprapubic skin advancement-ligamentolysis) and girth enhancement by dermal fat graft. Besides objective measurement, Male Genital Image Scale was used to facilitate selection of patients and evaluate the outcome, respectively. The change and shrinkage of the dermal fat strips was evaluated by ultrasound examination and computed tomography. No major complications or erection deficiencies occurred during the postoperative follow-up period. After 6 months, the mean flaccid length was increased by 2.27 ± 0.54 cm, whereas the mean flaccid circumference gain was 1.67 ± 0.46 cm. Significant improvement of genital satisfaction was reported during the follow-up. The shrinkage of dermal fat strips was inconspicuous, and no curvature was observed due to fibrosis. With strict patient selection, this procedure is proved to be a plausible and reasonable option for patients with penile dysmorphophobia. Also, it provides a potential alternative procedure to current dominant methods and promotes the aesthetic results with penile lengthening.

Dual-dermal-barrier fashion flaps for the treatment of sacral pressure sores.

Science.gov (United States)

Hsiao, Yen-Chang; Chuang, Shiow-Shuh

2015-02-01

The sacral region is one of the most vulnerable sites for the development of pressure sores. Even when surgical reconstruction is performed, there is a high chance of recurrence. Therefore, the concept of dual-dermal-barrier fashion flaps for sacral pressure sore reconstruction was proposed. From September 2007 to June 2010, nine patients with grade IV sacral pressures were enrolled. Four patients received bilateral myocutaneous V-Y flaps, four patients received bilateral fasciocutaneous V-Y flaps, and one patient received bilateral rotation-advanced flaps for sacral pressure reconstruction. The flaps were designed based on the perforators of the superior gluteal artery in one patient's reconstructive procedure. All flaps' designs were based on dual-dermal-barrier fashion. The mean follow-up time was 16 months (range = 12-25). No recurrence was noted. Only one patient had a complication of mild dehiscence at the middle suture line, occurring 2 weeks after the reconstructive surgery. The dual-dermal fashion flaps are easily duplicated and versatile. The study has shown minimal morbidity and a reasonable outcome.

Central Role for Dermal Fibroblasts in Skin Model Protection against Candida albicans.

Science.gov (United States)

Kühbacher, Andreas; Henkel, Helena; Stevens, Philip; Grumaz, Christian; Finkelmeier, Doris; Burger-Kentischer, Anke; Sohn, Kai; Rupp, Steffen

2017-06-01

The fungal pathogen Candida albicans colonizes basically all human epithelial surfaces, including the skin. Under certain conditions, such as immunosuppression, invasion of the epithelia occurs. Not much is known about defense mechanisms against C. albicans in subepithelial layers such as the dermis. Using immune cell-supplemented 3D skin models we defined a new role for fibroblasts in the dermis and identified a minimal set of cell types for skin protection against C. albicans invasion. Dual RNA sequencing of individual host cell populations and C. albicans revealed that dermal invasion is directly impeded by dermal fibroblasts. They are able to integrate signals from the pathogen and CD4+ T cells and shift toward an antimicrobial phenotype with broad specificity that is dependent on Toll-like receptor 2 and interleukin 1β. These results highlight a central function of dermal fibroblasts for skin protection, opening new possibilities for treatment of infectious diseases. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Coverage of Deep Cutaneous Wounds Using Dermal Template in Combination with Negative-pressure Therapy and Subsequent Skin Graft

Science.gov (United States)

Chang, Alexandre A.; Lobato, Rodolfo C.; Nakamoto, Hugo A.; Tuma, Paulo; Ferreira, Marcus C.

2014-01-01

Background: We consider the use of dermal matrix associated with a skin graft to cover deep wounds in the extremities when tendon and bone are exposed. The objective of this article was to evaluate the efficacy of covering acute deep wounds through the use of a dermal regeneration template (Integra) associated with vacuum therapy and subsequent skin grafting. Methods: Twenty patients were evaluated prospectively. All of them had acute (up to 3 weeks) deep wounds in the limbs. We consider a deep wound to be that with exposure of bone, tendon, or joint. Results: The average area of integration of the dermal regeneration template was 86.5%. There was complete integration of the skin graft over the dermal matrix in 14 patients (70%), partial integration in 5 patients (25%), and total loss in 1 case (5%). The wound has completely closed in 95% of patients. Conclusions: The use of Integra dermal template associated with negative-pressure therapy and skin grafting showed an adequate rate of resolution of deep wounds with low morbidity. PMID:25289363

A structured observational method to assess dermal exposure to manufactured nanoparticles: DREAM as an initial assessment tool

NARCIS (Netherlands)

Duuren-Stuurman, B. van; Pelzer, J.; Moehlmann, C.; Berges, M.; Bard, D.; Wake, D.; Mark, D.; Jankowska, E.; Brouwer, D.

2010-01-01

Preliminary results of inventories of exposure scenarios for nanomaterials have indicated possible dermal exposure. Within the NANOSH project focused on occupational safety and health aspects of nanotechnology a shortened version of the observational DeRmal Exposure AssessMent (DREAM) method was

The basic science of dermal fillers: past and present Part I: background and mechanisms of action.

Science.gov (United States)

Gilbert, Erin; Hui, Andrea; Waldorf, Heidi A

2012-09-01

Dermal fillers have provided a safe and effective means for aesthetic soft tissue augmentation, and have experienced a dramatic increase in popularity during the past 10 years. Much focus has been placed upon filler technique and patient outcomes. However, there is a relative lack of literature reviewing the basic science of dermal fillers, which is vital to a physician's understanding of how each product behaves in vivo. Part I of this article reviews the basic science and evolution of both historical and contemporary dermal fillers; Part II examines their adverse effects. We endeavor to provide the physician with a practical approach to choosing products that maximize both aesthetic outcome and safety.

Abdominal wall reconstruction using De-epithelialized dermal flap: A ...

African Journals Online (AJOL)

Abdominal wall reconstruction using De-epithelialized dermal flap: A new technique. ... Journal of Surgical Technique and Case Report ... Background: Although autogenous materials have been used in abdominal wall hernioplasty for a long time, the introduction of prosthetic materials diminished their popularity. However ...

Quantitative analysis of the synthesis and secretion of type VII collagen in cultured human dermal fibroblasts with a sensitive sandwich enzyme-linked immunoassay.

Science.gov (United States)

Amano, Satoshi; Ogura, Yuki; Akutsu, Nobuko; Nishiyama, Toshio

2007-02-01

Type VII collagen is the major component of anchoring fibrils in the epidermal basement membrane. Its expression has been analyzed by immunostaining or Northern blotting, but rarely at the protein level. In this study, we have quantitatively examined the effects of ascorbic acid and various cytokines/growth factors on the protein synthesis and secretion of type VII collagen by human dermal fibroblasts in culture, using a developed, highly sensitive sandwich enzyme-linked immunoassay with two kinds of specific monoclonal antibodies against the non-collagenous domain-1. Ascorbic acid and its derivative induced a twofold increase in type VII collagen synthesis, and markedly increased the secretion of type VII collagen into the medium when compared with the control culture. This effect was not influenced by the presence of transforming growth factor-beta1 (TGF-beta1). The synthesis of type VII collagen was elevated by TGF-beta1, platelet-derived growth factor, tumor necrosis factor-alpha, and interleukin-1beta, but not by TGF-alpha. Thus, our data indicate that the synthesis and secretion of type VII collagen in human dermal fibroblasts are regulated by ascorbate and the enhancement of type VII collagen gene expression by cytokines/growth factors is accompanied with elevated production of type VII collagen at the protein level.

Steroidal glycosides from the bulbs of Easter lily (Lilium longiflorum Thunb.) promote dermal fibroblast migration in vitro.

Science.gov (United States)

Esposito, Debora; Munafo, John P; Lucibello, Teresa; Baldeon, Manuel; Komarnytsky, Slavko; Gianfagna, Thomas J

2013-07-09

Preparations derived from bulbs of various Lilium species have been used to promote the healing of skin abrasions, sores and burns and to aid in healing wounds in Traditional Chinese and Greco-Roman Medicine. To evaluate fractionated Easter lily bulb extracts and their steroidal glycosides (1-5) for the promotion of dermal fibroblast migration in vitro, a model for the early events in wound healing. An activity-guided screening approach was used by coupling sequential solvent extraction, gel permeation chromatography (GPC), and semi-preparative reverse-phase high performance liquid chromatography (RP-HPLC) with an in vitro dermal fibroblast migration assay. Cytotoxicity was evaluated with methyl thiazole tetrazolium (MTT). To gain insight into the mode of action of the steroidal glycosides, nitric oxide (NO) production, and expression of genes for transforming growth factor beta-1 (TGF-β) and its receptors were evaluated. Fractionated bulb extracts and the two isolated steroidal glycoalkaloids (1) and (2) induced NO production and TGF-β receptor I mRNA expression in fibroblast cell culture. In a cytotoxicity assay, steroidal glycosides (1) and (3) had IC50 values of 8.2 and 8.7 µM, but the natural acetylation of the C-6″' hydroxy of the terminal glucose unit in (2) resulted in a 3-fold decrease in cell cytotoxicity when compared with (1). Results from the dermal fibroblast migration assay revealed that the steroidal glycoalkaloids (1) and (2), and the furostanol saponin (3) promoted fibroblast migration from the range of 23.7±5.7 to 37.7±5.1%, as compared with the control. Collectively, our data demonstrate that the steroidal glycosides present in Easter lily bulbs induce, at least in part, the observed dermal fibroblast migration activity of the bulb extracts. This is the first evidence that steroidal glycosides from Lilium longiflorum may potentially play a role in the wound healing process and may provide a scientific basis for the historical use of lily

Characterization and assessment of dermal and inhalable nickel exposures in nickel production and primary user industries.

Science.gov (United States)

Hughson, G W; Galea, K S; Heim, K E

2010-01-01

The aim of this study was to measure the levels of nickel in the skin contaminant layer of workers involved in specific processes and tasks within the primary nickel production and primary nickel user industries. Dermal exposure samples were collected using moist wipes to recover surface contamination from defined areas of skin. These were analysed for soluble and insoluble nickel species. Personal samples of inhalable dust were also collected to determine the corresponding inhalable nickel exposures. The air samples were analysed for total inhalable dust and then for soluble, sulfidic, metallic, and oxidic nickel species. The workplace surveys were carried out in five different workplaces, including three nickel refineries, a stainless steel plant, and a powder metallurgy plant, all of which were located in Europe. Nickel refinery workers involved with electrolytic nickel recovery processes had soluble dermal nickel exposure of 0.34 microg cm(-2) [geometric mean (GM)] to the hands and forearms. The GM of soluble dermal nickel exposure for workers involved in packing nickel salts (nickel chloride hexahydrate, nickel sulphate hexahydrate, and nickel hydroxycarbonate) was 0.61 microg cm(-2). Refinery workers involved in packing nickel metal powders and end-user powder operatives in magnet production had the highest dermal exposure (GM = 2.59 microg cm(-2) soluble nickel). The hands, forearms, face, and neck of these workers all received greater dermal nickel exposure compared with the other jobs included in this study. The soluble nickel dermal exposures for stainless steel production workers were at or slightly above the limit of detection (0.02 microg cm(-2) soluble nickel). The highest inhalable nickel concentrations were observed for the workers involved in nickel powder packing (GM = 0.77 mg m(-3)), although the soluble component comprised only 2% of the total nickel content. The highest airborne soluble nickel exposures were associated with refineries using

Task-based dermal exposure models for regulatory risk assessment

NARCIS (Netherlands)

Warren, N.D.; Marquart, H.; Christopher, Y.; Laitinen, J.; Hemmen, J.J. van

2006-01-01

The regulatory risk assessment of chemicals requires the estimation of occupational dermal exposure. Until recently, the models used were either based on limited data or were specific to a particular class of chemical or application. The EU project RISKOFDERM has gathered a considerable number of

Effect of pore size and cross-linking of a novel collagen-elastin dermal substitute on wound healing

NARCIS (Netherlands)

Boekema, B.K.H.L.; Vlig, M.; Damink, L.O.; Middelkoop, E.; Eummelen, L.; Buhren, A.V.; Ulrich, M.M.W.

2014-01-01

Collagen-elastin (CE) scaffolds are frequently used for dermal replacement in the treatment of full-thickness skin defects such as burn wounds. But little is known about the optimal pore size and level of cross-linking. Different formulations of dermal substitutes with unidirectional pores were

Wound healing effects of collagen-laminin dermal matrix impregnated with resveratrol loaded hyaluronic acid-DPPC microparticles in diabetic rats.

Science.gov (United States)

Gokce, Evren H; Tuncay Tanrıverdi, Sakine; Eroglu, Ipek; Tsapis, Nicolas; Gokce, Goksel; Tekmen, Isıl; Fattal, Elias; Ozer, Ozgen

2017-10-01

An alternative formulation for the treatment of diabetic foot wounds that heal slowly is a requirement in pharmaceutical field. The aim of this study was to develop a dermal matrix consisting of skin proteins and lipids with an antioxidant that will enhance healing and balance the oxidative stress in the diabetic wound area due to the high levels of glucose. Thus a novel three dimensional collagen-laminin porous dermal matrix was developed by lyophilization. Resveratrol-loaded hyaluronic acid and dipalmitoylphosphatidylcholine microparticles were combined with this dermal matrix. Characterization, in vitro release, microbiological and in vivo studies were performed. Spherical microparticles were obtained with a high RSV encapsulation efficacy. The microparticles were well dispersed in the dermal matrix from the surface to deeper layers. Collagenase degraded dermal matrix, however the addition of RSV loaded microparticles delayed the degradation time. The release of RSV was sustained and reached 70% after 6h. Histological changes and antioxidant parameters in different treatment groups were investigated in full-thickness excision diabetic rat model. Collagen fibers were intense and improved by the presence of formulation without any signs of inflammation. The highest healing score was obtained with the dermal matrix impregnated with RSV-microparticles with an increased antioxidant activity. Collagen-laminin dermal matrix with RSV microparticles was synergistically effective due to presence of skin components in the formulation and controlled release achieved. This combination is a safe and promising option for the treatment of diabetic wounds requiring long recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

Differentiation within autologous fibrin scaffolds of porcine dermal cells with the mesenchymal stem cell phenotype

International Nuclear Information System (INIS)

Puente, Pilar de la; Ludeña, Dolores; López, Marta; Ramos, Jennifer; Iglesias, Javier

2013-01-01

Porcine mesenchymal stem cells (pMSCs) are an attractive source of cells for tissue engineering because their properties are similar to those of human stem cells. pMSCs can be found in different tissues but their dermal origin has not been studied in depth. Additionally, MSCs differentiation in monolayer cultures requires subcultured cells, and these cells are at risk of dedifferentiation when implanting them into living tissue. Following this, we attempted to characterize the MSCs phenotype of porcine dermal cells and to evaluate their cellular proliferation and differentiation in autologous fibrin scaffolds (AFSs). Dermal biopsies and blood samples were obtained from 12 pigs. Dermal cells were characterized by flow cytometry. Frozen autologous plasma was used to prepare AFSs. pMSC differentiation was studied in standard structures (monolayers and pellets) and in AFSs. The pMSCs expressed the CD90 and CD29 markers of the mesenchymal lineage. AFSs afforded adipogenic, osteogenic and chondrogenic differentiation. The porcine dermis can be proposed to be a good source of MSCs with adequate proliferative capacity and a suitable expression of markers. The pMSCs also showed optimal proliferation and differentiation in AFSs, such that these might serve as a promising autologous and implantable material for use in tissue engineering. -- Highlights: ► Low fibrinogen concentration provides a suitable matrix for cell migration and differentiation. ► Autologous fibrin scaffolds is a promising technique in tissue engineering. ► Dermal cells are an easily accessible mesenchymal stem cell source. ► Fibrin scaffolds afforded adipogenic, osteogenic and chondrogenic differentiation.

Histology of the heterostracan dermal skeleton: Insight into the origin of the vertebrate mineralised skeleton.

Science.gov (United States)

Keating, Joseph N; Marquart, Chloe L; Donoghue, Philip C J

2015-06-01

Living vertebrates are divided into those that possess a fully formed and fully mineralised skeleton (gnathostomes) versus those that possess only unmineralised cartilaginous rudiments (cyclostomes). As such, extinct phylogenetic intermediates of these living lineages afford unique insights into the evolutionary assembly of the vertebrate mineralised skeleton and its canonical tissue types. Extinct jawless and jawed fishes assigned to the gnathostome stem evidence the piecemeal assembly of skeletal systems, revealing that the dermal skeleton is the earliest manifestation of a homologous mineralised skeleton. Yet the nature of the primitive dermal skeleton, itself, is poorly understood. This is principally because previous histological studies of early vertebrates lacked a phylogenetic framework required to derive evolutionary hypotheses. Nowhere is this more apparent than within Heterostraci, a diverse clade of primitive jawless vertebrates. To this end, we surveyed the dermal skeletal histology of heterostracans, inferred the plesiomorphic heterostracan skeleton and, through histological comparison to other skeletonising vertebrate clades, deduced the ancestral nature of the vertebrate dermal skeleton. Heterostracans primitively possess a four-layered skeleton, comprising a superficial layer of odontodes composed of dentine and enameloid; a compact layer of acellular parallel-fibred bone containing a network of vascular canals that supply the pulp canals (L1); a trabecular layer consisting of intersecting radial walls composed of acellular parallel-fibred bone, showing osteon-like development (L2); and a basal layer of isopedin (L3). A three layered skeleton, equivalent to the superficial layer L2 and L3 and composed of enameloid, dentine and acellular bone, is possessed by the ancestor of heterostracans + jawed vertebrates. We conclude that an osteogenic component is plesiomorphic with respect to the vertebrate dermal skeleton. Consequently, we interpret the

{sup 14}C-Methylenebisphenylisocyanate ({sup 14}C-MDI). Study of absorption after single dermal and intradermal administration in rats

Energy Technology Data Exchange (ETDEWEB)

Leibold, E.; Hoffmann, H.D.; Hildebrand, B

1999-07-01

The absorption, distribution and excretion of radioactivity was studied in groups of four male Wistar rats following a single dermal and intradermal administration of {sup 14}C- Methylenebisphenylisocyanate ({sup 14}C-MDI) at nominal dose levels of 4.0 and 0.4 mg/cm{sup 2} for dermal administration and 0.4 mg/animal for intradermal administration. These dose levels nominally corresponded to 40 and 4.0 mg/animal for dermal administration. Considering the animal weights, dose levels corresponded to about 140 and 14 mg/kg body weight (dermal administration) and 1.4 mg/kg body weight (intradermal administration). In the experiments with dermal administration, animals were exposed for 8 hours and sacrificed 8, 24 or 120 h after beginning of exposure. In the experiment with intradermal administration, animals were sacrificed 120 h after treatment. After dermal administration of {sup 14}C-MDI, mean recoveries of radioactivity from all dose groups were in the range from 97.86 to 108.07% of the total radioactivity administered. Generally, the largest proportion of radioactivity was found at the application site and dressing. The total amount of radioactivity absorbed (including excreta, cage wash, tissues/organs and carcass) increased with increasing sacrifice time. Dermal absorption was very low and quantitatively similar at both dose levels; maximally ca. 0.9 % of the applied radioactivity was absorbed. After intradermal administration of {sup 14}C-MDI, the mean recovery of radioactivity was 100.90 % of the radioactivity administered. The largest proportion of radioactivity was found at the application site. The total amount of radioactivity absorbed (including excreta, cage wash, tissues/organs and carcass) amounted to about 26 % of the radioactivity applied. Irrespective of the mode of administration of 1{sup 4C}-MDI, concentrations of radioactivity in tissues and organs generally were below 1 {mu}g Eq/g at 120 h after administration. In summary, the results of this

Efficient dermal delivery of retinyl palmitate: Progressive polarimetry and Raman spectroscopy to evaluate the structure and efficacy.

Science.gov (United States)

Lee, Jun Bae; Lee, Dong Ryeol; Choi, Nak Cho; Jang, Jihui; Park, Chun Ho; Yoon, Moung Seok; Lee, Miyoung; Won, Kyoungae; Hwang, Jae Sung; Kim, B Moon

2015-10-12

Over the past decades, there has been a growing interest in dermal drug delivery. Although various novel delivery devices and methods have been developed, dermal delivery is still challenging because of problems such as poor drug permeation, instability of vesicles and drug leakage from vesicles induced by fusion of vesicles. To solve the vesicle instability problems in current dermal delivery systems, we developed materials comprised of liquid crystals as a new delivery vehicle of retinyl palmitate and report the characterization of the liquid crystals using a Mueller matrix polarimetry. The stability of the liquid-crystal materials was evaluated using the polarimeter as a novel evaluation tool along with other conventional methods. The dermal delivery of retinyl palmitate was investigated through the use of confocal Raman spectroscopy. The results indicate that the permeation of retinyl palmitate was enhanced by up to 106% compared to that using an ordinary emulsion with retinyl palmitate. Copyright © 2015 Elsevier B.V. All rights reserved.

Abdominal wall reconstruction using De-epithelialized dermal flap: A ...

African Journals Online (AJOL)

Background: Although autogenous materials have been used in abdominal wall hernioplasty for a long time, the introduction of prosthetic materials diminished their popularity. However, these materials may be expensive, inappropriate or unavailable. The aim of this study is to determine the place of de-epithelialized dermal ...

Implanon sub-dermal implant: an emerging method of contraception ...

African Journals Online (AJOL)

Implanon, a single rod sub-dermal implant is a relatively new contraceptive which offers long term reversible contraception for women. This study seeks to determine the safety, efficacy and acceptor characteristics of Implanon at the family planning clinic of University of Ilorin Teaching Hospital (UITH), Ilorin, Nigeria.

Dermal exposure to jet fuel JP-8 significantly contributes to the production of urinary naphthols in fuel-cell maintenance workers.

Science.gov (United States)

Chao, Yi-Chun E; Kupper, Lawrence L; Serdar, Berrin; Egeghy, Peter P; Rappaport, Stephen M; Nylander-French, Leena A

2006-02-01

Jet propulsion fuel 8 (JP-8) is the major jet fuel used worldwide and has been recognized as a major source of chemical exposure, both inhalation and dermal, for fuel-cell maintenance workers. We investigated the contributions of dermal and inhalation exposure to JP-8 to the total body dose of U.S. Air Force fuel-cell maintenance workers using naphthalene as a surrogate for JP-8 exposure. Dermal, breathing zone, and exhaled breath measurements of naphthalene were obtained using tape-strip sampling, passive monitoring, and glass bulbs, respectively. Levels of urinary 1- and 2-naphthols were determined in urine samples and used as biomarkers of JP-8 exposure. Multiple linear regression analyses were conducted to investigate the relative contributions of dermal and inhalation exposure to JP-8, and demographic and work-related covariates, to the levels of urinary naphthols. Our results show that both inhalation exposure and smoking significantly contributed to urinary 1-naphthol levels. The contribution of dermal exposure was significantly associated with levels of urinary 2-naphthol but not with urinary 1-naphthol among fuel-cell maintenance workers who wore supplied-air respirators. We conclude that dermal exposure to JP-8 significantly contributes to the systemic dose and affects the levels of urinary naphthalene metabolites. Future work on dermal xenobiotic metabolism and toxicokinetic studies are warranted in order to gain additional knowledge on naphthalene metabolism in the skin and the contribution to systemic exposure.

Dermal transfer quantification of nanoparticles from nano-enabled surfaces

DEFF Research Database (Denmark)

Mackevica, Aiga; Olsson, Mikael Emil; Mines, Paul D.

2018-01-01

). The dermal transfer testing by wipe sampling and analytical approach used in this study demonstrates that wipe testing in combination with spICP-MS analysis can provide both qualitative data in terms of mass and number-based NP release, as well as particle characterization in terms of NP size distribution...... and characterize NP release from keyboard covers and freshly painted surfaces, in terms of mass and number concentration, as well as released particle size distribution through the use of spICP-MS. Three types of NPs were selected for method validation testing, Ag, TiO2, and CuO; and, the particle extraction from...... wipes was found to be efficient for Ag and CuO, but not for TiO2 particles. Thereafter, potential dermal transfer was tested by wipe sampling for two nanoAg-containing silicon keyboard covers, and wood painted with nanoCuO-containing paint. AgNP release was observed for one of the keyboard cover types...

Parameter optimization toward optimal microneedle-based dermal vaccination.

Science.gov (United States)

van der Maaden, Koen; Varypataki, Eleni Maria; Yu, Huixin; Romeijn, Stefan; Jiskoot, Wim; Bouwstra, Joke

2014-11-20

Microneedle-based vaccination has several advantages over vaccination by using conventional hypodermic needles. Microneedles are used to deliver a drug into the skin in a minimally-invasive and potentially pain free manner. Besides, the skin is a potent immune organ that is highly suitable for vaccination. However, there are several factors that influence the penetration ability of the skin by microneedles and the immune responses upon microneedle-based immunization. In this study we assessed several different microneedle arrays for their ability to penetrate ex vivo human skin by using trypan blue and (fluorescently or radioactively labeled) ovalbumin. Next, these different microneedles and several factors, including the dose of ovalbumin, the effect of using an impact-insertion applicator, skin location of microneedle application, and the area of microneedle application, were tested in vivo in mice. The penetration ability and the dose of ovalbumin that is delivered into the skin were shown to be dependent on the use of an applicator and on the microneedle geometry and size of the array. Besides microneedle penetration, the above described factors influenced the immune responses upon microneedle-based vaccination in vivo. It was shown that the ovalbumin-specific antibody responses upon microneedle-based vaccination could be increased up to 12-fold when an impact-insertion applicator was used, up to 8-fold when microneedles were applied over a larger surface area, and up to 36-fold dependent on the location of microneedle application. Therefore, these influencing factors should be considered to optimize microneedle-based dermal immunization technologies. Copyright © 2014 Elsevier B.V. All rights reserved.

NOD2 and TLR2 ligands trigger the activation of basophils and eosinophils by interacting with dermal fibroblasts in atopic dermatitis-like skin inflammation

Science.gov (United States)

Jiao, Delong; Wong, Chun-Kwok; Qiu, Huai-Na; Dong, Jie; Cai, Zhe; Chu, Man; Hon, Kam-Lun; Tsang, Miranda Sin-Man; Lam, Christopher Wai-Kei

2016-01-01

The skin of patients with atopic dermatitis (AD) has a unique predisposition for colonization by Staphylococcus aureus (S. aureus), which contributes to the inflammation and grim prognosis of AD. Although the mechanism underlying the S. aureus-induced exacerbation of AD remains unclear, recent studies have found a pivotal role for pattern recognition receptors in regulating the inflammatory responses in S. aureus infection. In the present study, we used a typical mouse model of AD-like skin inflammation and found that S. aureus-associated nucleotide-binding oligomerization domain-containing protein 2 (NOD2) and toll-like receptor 2 (TLR2) ligands exacerbated AD-like symptoms, which were further deteriorated by the in vivo expansion of basophils and eosinophils. Subsequent histological analyses revealed that dermal fibroblasts were pervasive in the AD-like skin lesions. Co-culture of human dermal fibroblasts with basophils and eosinophils resulted in a vigorous cytokine/chemokine response to the NOD2/TLR2 ligands and the enhanced expression of intercellular adhesion molecule-1 on the dermal fibroblasts. Basophils and eosinophils were primarily responsible for the AD-related cytokine/chemokine expression in the co-cultures. Direct intercellular contact was necessary for the crosstalk between basophils and dermal fibroblasts, while soluble mediators were sufficient to mediate the eosinophil–fibroblast interactions. Moreover, the intracellular p38 mitogen-activated protein kinase, extracellular signal-regulated kinase, and nuclear factor-kappa B signaling pathways were essential for NOD2/TLR2 ligand-mediated activation of basophils, eosinophils, and dermal fibroblasts in AD-related inflammation. This study provides the evidence of NOD2/TLR2-mediated exacerbation of AD through activation of innate immune cells and therefore sheds light on a novel mechanistic pathway by which S. aureus contributes to the pathophysiology of AD. PMID:26388234

A Bayesian statistical analysis of mouse dermal tumor promotion assay data for evaluating cigarette smoke condensate.

Science.gov (United States)

Kathman, Steven J; Potts, Ryan J; Ayres, Paul H; Harp, Paul R; Wilson, Cody L; Garner, Charles D

2010-10-01

The mouse dermal assay has long been used to assess the dermal tumorigenicity of cigarette smoke condensate (CSC). This mouse skin model has been developed for use in carcinogenicity testing utilizing the SENCAR mouse as the standard strain. Though the model has limitations, it remains as the most relevant method available to study the dermal tumor promoting potential of mainstream cigarette smoke. In the typical SENCAR mouse CSC bioassay, CSC is applied for 29 weeks following the application of a tumor initiator such as 7,12-dimethylbenz[a]anthracene (DMBA). Several endpoints are considered for analysis including: the percentage of animals with at least one mass, latency, and number of masses per animal. In this paper, a relatively straightforward analytic model and procedure is presented for analyzing the time course of the incidence of masses. The procedure considered here takes advantage of Bayesian statistical techniques, which provide powerful methods for model fitting and simulation. Two datasets are analyzed to illustrate how the model fits the data, how well the model may perform in predicting data from such trials, and how the model may be used as a decision tool when comparing the dermal tumorigenicity of cigarette smoke condensate from multiple cigarette types. The analysis presented here was developed as a statistical decision tool for differentiating between two or more prototype products based on the dermal tumorigenicity. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Dermal Wound Transcriptomic Responses to Infection with Pseudomonas aeruginosa versus Klebsiella pneumoniae in a Rabbit Ear Wound Model

Science.gov (United States)

2014-05-02

intradermally with 1% lidocaine /1:100,000 epinephrine at the wound sites. A total of 18 rabbits were used. Four, 6-mm diameter, full-thickness dermal wounds...based on literature compiled in the Ingenuity® Knowledge Base, to include: ‘adhesion of immune cells’, ‘ synthesis of reactive oxygen species... synthesis of specific transcription factors and their target genes that support recovery from the stress (e.g., ER chaperones, oxidoreductases, and ERAD

Laboratory Validation and Field Assessment of Petroleum Laboratory Technicians' Dermal Exposure to Crude Oil Using a Wipe Sampling Method.

Science.gov (United States)

Galea, Karen S; Mueller, Will; Arfaj, Ayman M; Llamas, Jose L; Buick, Jennifer; Todd, David; McGonagle, Carolyn

2018-05-21

Crude oil may cause adverse dermal effects therefore dermal exposure is an exposure route of concern. Galea et al. (2014b) reported on a study comparing recovery (wipe) and interception (cotton glove) dermal sampling methods. The authors concluded that both methods were suitable for assessing dermal exposure to oil-based drilling fluids and crude oil but that glove samplers may overestimate the amount of fluid transferred to the skin. We describe a study which aimed to further evaluate the wipe sampling method to assess dermal exposure to crude oil, with this assessment including extended sample storage periods and sampling efficiency tests being undertaken at environmental conditions to mimic those typical of outdoor conditions in Saudi Arabia. The wipe sampling method was then used to assess the laboratory technicians' actual exposure to crude oil during typical petroleum laboratory tasks. Overall, acceptable storage efficiencies up to 54 days were reported with results suggesting storage stability over time. Sampling efficiencies were also reported to be satisfactory at both ambient and elevated temperature and relative humidity environmental conditions for surrogate skin spiked with known masses of crude oil and left up to 4 h prior to wiping, though there was an indication of reduced sampling efficiency over time. Nineteen petroleum laboratory technicians provided a total of 35 pre- and 35 post-activity paired hand wipe samples. Ninety-three percent of the pre-exposure paired hand wipes were less than the analytical limit of detection (LOD), whereas 46% of the post-activity paired hand wipes were less than the LOD. The geometric mean paired post-activity wipe sample measurement was 3.09 µg cm-2 (range 1.76-35.4 µg cm-2). It was considered that dermal exposure most frequently occurred through direct contact with the crude oil (emission) or via deposition. The findings of this study suggest that the wipe sampling method is satisfactory in quantifying

Isolation of intact sub-dermal secretory cavities from Eucalyptus

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Goodger Jason QD

2010-09-01

Full Text Available Abstract Background The biosynthesis of plant natural products in sub-dermal secretory cavities is poorly understood at the molecular level, largely due to the difficulty of physically isolating these structures for study. Our aim was to develop a protocol for isolating live and intact sub-dermal secretory cavities, and to do this, we used leaves from three species of Eucalyptus with cavities that are relatively large and rich in essential oils. Results Leaves were digested using a variety of commercially available enzymes. A pectinase from Aspergillus niger was found to allow isolation of intact cavities after a relatively short incubation (12 h, with no visible artifacts from digestion and no loss of cellular integrity or cavity contents. Several measurements indicated the potential of the isolated cavities for further functional studies. First, the cavities were found to consume oxygen at a rate that is comparable to that estimated from leaf respiratory rates. Second, mRNA was extracted from cavities, and it was used to amplify a cDNA fragment with high similarity to that of a monoterpene synthase. Third, the contents of the cavity lumen were extracted, showing an unexpectedly low abundance of volatile essential oils and a sizeable amount of non-volatile material, which is contrary to the widely accepted role of secretory cavities as predominantly essential oil repositories. Conclusions The protocol described herein is likely to be adaptable to a range of Eucalyptus species with sub-dermal secretory cavities, and should find wide application in studies of the developmental and functional biology of these structures, and the biosynthesis of the plant natural products they contain.

Biocompatibility and tissue regenerating capacity of crosslinked dermal sheep collagen

NARCIS (Netherlands)

van Wachem, P.B.; van Luyn, M.J.A.; Olde Damink, L.H.H.; Olde damink, L.H.H.; Dijkstra, Pieter J.; Feijen, Jan; Nieuwenhuis, P.

1994-01-01

The biocompatibility and tissue regenerating capacity of four crosslinked dermal sheep collagens (DSC) was studied. In vitro, the four DSC versions were found to be noncytotoxic or very low in cytoxicity. After subcutaneous implantation in rats, hexamethylenediisocyanatecrcrosslinked DSC (HDSC)

Comparison of Calcium and Barium Microcapsules as Scaffolds in the Development of Artificial Dermal Papillae.

Science.gov (United States)

Liu, Yang; Lin, Changmin; Zeng, Yang; Li, Haihong; Cai, Bozhi; Huang, Keng; Yuan, Yanping; Li, Yu

2016-01-01

This study aimed to develop and evaluate barium and calcium microcapsules as candidates for scaffolding in artificial dermal papilla. Dermal papilla cells (DPCs) were isolated and cultured by one-step collagenase treatment. The DPC-Ba and DPC-Ca microcapsules were prepared by using a specially designed, high-voltage, electric-field droplet generator. Selected microcapsules were assessed for long-term inductive properties with xenotransplantation into Sprague-Dawley rat ears. Both barium and calcium microcapsules maintained xenogenic dermal papilla cells in an immunoisolated environment and induced the formation of hair follicle structures. Calcium microcapsules showed better biocompatibility, permeability, and cell viability in comparison with barium microcapsules. Before 18 weeks, calcium microcapsules gathered together, with no substantial immune response. After 32 weeks, some microcapsules were near inflammatory cells and wrapped with fiber. A few large hair follicles were found. Control samples showed no marked changes at the implantation site. Barium microcapsules were superior to calcium microcapsules in structural and mechanical stability. The cells encapsulated in hydrogel barium microcapsules exhibited higher short-term viability. This study established a model to culture DPCs in 3D culture conditions. Barium microcapsules may be useful in short-term transplantation study. Calcium microcapsules may provide an effective scaffold for the development of artificial dermal papilla.

RELATIONS BETWEEN INVITRO CYTOTOXICITY AND CROSS-LINKED DERMAL SHEEP COLLAGENS

NARCIS (Netherlands)

VANLUYN, MJA; VANWACHEM, PB; DAMINK, LO; DIJKSTRA, PJ; FEIJEN, J; NIEUWENHUIS, P

Collagen-based biomaterials have found various applications in the biomedical field. However, collagen-based biomaterials may induce cytotoxic effects. This study evaluated possible cytotoxic effects of (crosslinked) dermal sheep collagen (DSC) using a 7-d-methylcellulose cell culture with human

In vivo and in vitro dermal penetration of 2,4,5,2',4', 5'-hexachlorobiphenyl in young and adult rats

International Nuclear Information System (INIS)

Shah, P.V.; Sumler, M.R.; Fisher, H.L.; Hall, L.L.

1989-01-01

Penetration of 2,4,5,2',4',5'-[ 14 C]hexachlorobiphenyl (HCB) through skin of young (33 days) and adult (82 days) female Fischer 344 rats was determined in vivo and by two in vitro methods. In vivo dermal penetration at 120 hr was 45% in young and 43% in adults. At 72 hr in vivo dermal penetration was 35% in young and 26% in adults compared to 1.5% for young and 1.0% for adult as measured with a continuous flow in vitro system and 2.9% for young and 1.9% for adults as measured with a static in vitro system. Most of the dermally absorbed HCB remained in the body as only 4.9 and 2.6% of that absorbed was excreted by young and adult rats, respectively, at the end of 120 hr. Significant differences in dermal penetration and kinetics of HCB between young and adult female rats were observed. The elimination of ECB-derived material was approximately six times higher in feces than in urine. A physiological pharmacokinetic model was fitted to the organ and tissue radioactivity distribution data. Parameters in the model determined from dermal dosing of female Fischer 344 rats were in reasonable agreement with those reported in the literature for adult male Sprague-Dawley rats (iv dose). The rate constant for dermal penetration was 0.83 x 10 -4 min -1 for adults and 0.96 x 10 -4 min -1 for young. The delay or lag time parameter for dermal penetration was 4.4 hr in adults and 1.1 hr in young

Genomic regions associated with the sex-linked inhibitor of dermal melanin in Silkie chicken

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Ming TIAN,Rui HAO,Suyun FANG,Yanqiang WANG,Xiaorong GU,Chungang FENG,Xiaoxiang HU,Ning LI

2014-09-01

Full Text Available A unique characteristic of the Silkie chicken is its fibromelanosis phenotype. The dermal layer of its skin, its connective tissue and shank dermis are hyperpigmented. This dermal hyperpigmentation phenotype is controlled by the sex-linked inhibitor of dermal melanin gene (ID and the dominant fibromelanosis allele. This study attempted to confirm the genomic region associated with ID. By genotyping, ID was found to be closely linked to the region between GGA_rs16127903 and GGA_rs14685542 (8406919 bp on chromosome Z, which contains ten functional genes. The expression of these genes was characterized in the embryo and 4 days after hatching and it was concluded that MTAP, encoding methylthioadenosinephosphorylase, would be the most likely candidate gene. Finally, target DNA capture and sequence analysis was performed, but no specific SNP(s was found in the targeted region of the Silkie genome. Further work is necessary to identify the causal ID mutation located on chromosome Z.

One-stage reconstruction of soft tissue defects with the sandwich technique: Collagen-elastin dermal template and skin grafts

Directory of Open Access Journals (Sweden)

Uwe Wollina

2011-01-01

Full Text Available Background : A full-thickness soft tissue defect closure often needs complex procedures. The use of dermal templates can be helpful in improving the outcome. Objective : The objective was to evaluate a sandwich technique combining the dermal collagen-elastin matrix with skin grafts in a one-stage procedure. Materials and Methods : Twenty-three patients with 27 wounds were enrolled in this prospective single-centre observational study. The mean age was 74.8 ± 17.2 years. Included were full-thickness defects with exposed bone, cartilage and/ or tendons. The dermal collagen-elastin matrix was applied onto the wound bed accomplished by skin transplants, i.e. ′sandwich′ transplantation. In six wounds, the transplants were treated with intermittent negative pressure therapy. Results : The size of defects was ≤875 cm 2 . The use of the dermal template resulted in a complete and stable granulation in 100% of wounds. Seventeen defects showed a complete closure and 19 achieved a complete granulation with an incomplete closure. There was a marked pain relief. No adverse events were noted due to the dermal template usage. Conclusions : Sandwich transplantation with the collagen-elastin matrix is a useful tool when dealing with full-thickness soft tissue defects with exposed bone, cartilage or tendons.

Dermal absorption and distribution of 14 C carbaryl in wistar rats

International Nuclear Information System (INIS)

Tos-Luty, S.; Tokarska-Rodak, M.; Latuszynska, J.; Przebirowska, D.

2001-01-01

The level of 14 C carbaryl was determined in blood (leukocytes, erythrocytes, all blood cells, plasma) and organs (brain, heart, lungs, liver, spleen, skin at the site of exposure) of male Wistar rats after dermal administration. The application liquid was 14 C carbaryl solution in 96% ethyl alcohol. This preparation, possessing an activity of 670 kBq/ml, containing 1.67 mg of carbaryl, was applied to the skin of the tail according to Massmann's method in own modification. The amount of the preparation per 1 cm 2 of the tail skin was 0.19 mg of carbaryl (74.4 kBq). The tails of experimental rats were exposed to 14 C carbaryl by soaking for 4 h daily: once, twice or three times. Beta radiation from 14 C was measured in homogenized organs (brain, heart, lungs, liver, skin) and in blood by computer controlled Wallac scintillation counter Model 1409, using Multi Calc software. The dermal absorption of carbaryl at the site of exposure and in the surrounding area of about 2 cm was observed already during 4 hour exposure. Carbaryl reached plasma within 4 h of a single dermal exposure and penetrated into leukocytes, erythrocytes, heart, liver, lung, kidney and brain. The largest amount of 14 C carbaryl, about 2% of absorbed dose, was detected in liver. (author)

Securing the Airway in Pretracheal Dermal Metastases From Oropharyngeal Carcinoma: A Case Report.

Science.gov (United States)

Truong, Angela T; Truong, Dam-Thuy; Gillenwater, Ann M; Soliz, Jose M; Rahlfs, Thomas F

2018-04-23

Dermal metastases reflect the ominous and aggressive spread of oropharyngeal squamous cell carcinomas. The rampant proliferation of these metastatic tumors to the neck results in respiratory distress and impending airway obstruction. We report a case of a patient with massive neck dermal metastases requiring urgent airway control for intermittent stridor. Awake tracheostomy is generally regarded as the gold standard to manage the compromised airway. However, in this unusual case, after discussion between surgeon and anesthesiologist, because of the anticipated formidable difficulties in performing awake tracheostomy, it was decided that awake fiberoptic intubation would provide the best chance of success.

Zinc oxide nanoparticles: a 90-day repeated-dose dermal toxicity study in rats

Directory of Open Access Journals (Sweden)

Ryu HJ

2014-12-01

Full Text Available Hwa Jung Ryu,1,* Mu Yeb Seo,2,* Sung Kyu Jung,1 Eun Ho Maeng,2 Seung-Young Lee,2 Dong-Hyouk Jang,2 Taek-Jin Lee,2 Ki-Yeon Jo,2 Yu-Ri Kim,3 Kyu-Bong Cho,4 Meyoung-Kon Kim,3 Beom Jun Lee,5 Sang Wook Son1 1Department of Dermatology, Korea University College of Medicine, Seoul, 2Korea Testing and Research Institute, Gyunggido, 3Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul, 4Department of Clinical Laboratory Science, Shinheung College, Uijeongbu, 5College of Veterinary Medicine, Chungbuk National University, Cheongju, Republic of Korea *These authors contributed equally to this work and both should be considered first authors Abstract: Zinc oxide (ZnO works as a long-lasting, broad-spectrum physical sunblock, and can prevent skin cancer, sunburn, and photoaging. Nanosized ZnO particles are used often in sunscreens due to consumer preference over larger sizes, which appear opaque when dermally applied. Although the US Food and Drug Administration approved the use of nanoparticles (NPs in sunscreens in 1999, there are ongoing safety concerns. The aim of this study was to evaluate the subchronic toxicity of ZnO NPs after dermal application according to the Organization for Economic Cooperation and Development Test Guidelines 411 using Good Laboratory Practice. Sprague Dawley rats were randomly divided into eight (one control, one vehicle control, three experimental, and three recovery groups. Different concentrations of ZnO NPs were dermally applied to the rats in the experimental groups for 90 days. Clinical observations as well as weight and food consumption were measured and recorded daily. Hematology and biochemistry parameters were determined. Gross pathologic and histopathologic examinations were performed on selected tissues from all animals. Analyses of tissue were undertaken to determine target organ tissue distribution. There was no increased mortality in the experimental group. Although there

Molecular biological and immunohistological characterization of canine dermal papilla cells and the evaluation of culture conditions.

Science.gov (United States)

Kobayashi, Tetsuro; Fujisawa, Akiko; Amagai, Masayuki; Iwasaki, Toshiroh; Ohyama, Manabu

2011-10-01

The dermal papilla (DP) plays pivotal roles in hair follicle morphogenesis and cycling. However, our understanding of the biology of the canine DP is extremely limited. The aim of this study was to elucidate molecular biological and immunohistochemical characteristics of canine DP cells and determine appropriate conditions for in vitro expansion. Histological investigation revealed that the canine DP expressed biomarkers of human and rodent DP, including alkaline phosphatase (ALP) and versican. When microdissected, canine DP, but not fibroblasts, strongly expressed the DP-related genes for alkaline phosphatase, Wnt inhibitory factor 1 and lymphoid enhancer-binding factor 1, confirming successful isolation. The growth rate of isolated canine DP cells was moderate in conventional culture conditions for rodent and human DP; however, AmnioMAX-C100 complete medium allowed more efficient cultivation. Dermal papilla marker gene expression was maintained in early passage cultured DP cells, but gradually lost after the third passage. Approaches to mimic the in vivo DP environment in culture, such as supplementation of keratinocyte-conditioned medium or use of extracellular matrix-coated dishes, moderately ameliorated loss of DP gene expression in canine DP cells. It is possible that constituent factors in AmnioMAX may influence culture. These findings suggested that further refinements of culture conditions may enable DP cell expansion without impairing intrinsic properties and, importantly, demonstrated that AmnioMAX-cultured early passage canine DP cells partly maintained the biological characteristics of in vivo canine DP cells. This study provides crucial information necessary for further optimization of culture conditions of canine DP. © 2011 The Authors. Veterinary Dermatology. © 2011 ESVD and ACVD.

Laminin peptide YIGSR induces collagen synthesis in Hs27 human dermal fibroblasts

International Nuclear Information System (INIS)

Yoon, Jong Hyuk; Kim, Jaeyoon; Lee, Hyeongjoo; Kim, So Young; Jang, Hwan-Hee; Ryu, Sung Ho; Kim, Beom Joon; Lee, Taehoon G.

2012-01-01

Highlights: ► We identify a function of the YIGSR peptide to enhance collagen synthesis in Hs27. ► YIGSR peptide enhanced collagen type 1 synthesis both of gene and protein levels. ► There were no changes in cell proliferation and MMP-1 level in YIGSR treatment. ► The YIGSR effect on collagen synthesis mediated activation of FAK, pyk2 and ERK. ► The YIGSR-induced FAK and ERK activation was modulated by FAK and MEK inhibitors. -- Abstract: The dermal ECM is synthesized from fibroblasts and is primarily compromised of fibrillar collagen and elastic fibers, which support the mechanical strength and resiliency of skin, respectively. Laminin, a major glycoprotein located in the basement membrane, promotes cell adhesion, cell growth, differentiation, and migration. The laminin tyrosine-isoleucine-glycine-serine-arginine (YIGSR) peptide, corresponding to the 929–933 sequence of the β1 chain, is known to be a functional motif with effects on the inhibition of tumor metastasis, the regulation of sensory axonal response and the inhibition of angiogenesis through high affinity to the 67 kDa laminin receptor. In this study, we identified a novel function of the YIGSR peptide to enhance collagen synthesis in human dermal fibroblasts. To elucidate this novel function regarding collagen synthesis, we treated human dermal fibroblasts with YIGSR peptide in both a time- and dose-dependent manner. According to subsequent experiments, we found that the YIGSR peptide strongly enhanced collagen type 1 synthesis without changing cell proliferation or cellular MMP-1 level. This YIGSR peptide-mediated collagen type 1 synthesis was modulated by FAK inhibitor and MEK inhibitor. This study clearly reveals that YIGSR peptide plays a novel function on the collagen type 1 synthesis of dermal fibroblasts and also suggests that YIGSR is a strong candidate peptide for the treatment of skin aging and wrinkles.

A multicenter randomized controlled trial comparing absorbable barbed sutures versus conventional absorbable sutures for dermal closure in open surgical procedures.

Science.gov (United States)

Rubin, J Peter; Hunstad, Joseph P; Polynice, Alain; Gusenoff, Jeffrey A; Schoeller, Thomas; Dunn, Raymond; Walgenbach, Klaus J; Hansen, Juliana E

2014-02-01

Barbed sutures were developed to reduce operative time and improve security of wound closure. The authors compare absorbable barbed sutures (V-Loc, Covidien, Mansfield, Massachusetts) with conventional (smooth) absorbable sutures for soft tissue approximation. A prospective multicenter randomized study comparing barbed sutures with smooth sutures was undertaken between August 13, 2009, and January 31, 2010, in 241 patients undergoing abdominoplasty, mastopexy, and reduction mammaplasty. Each patient received barbed sutures on 1 side of the body, with deep dermal sutures eliminated or reduced. Smooth sutures with deep dermal and subcuticular closure were used on the other side as a control. The primary endpoint was dermal closure time. Safety was assessed through adverse event reporting through a 12-week follow-up. A total of 229 patients were ultimately treated (115 with slow-absorbing polymer and 114 with rapid-absorbing polymer). Mean dermal closure time was significantly quicker with the barbed suture compared with the smooth suture (12.0 vs 19.2 minutes; P<.001), primarily due to the need for fewer deep dermal sutures. The rapid-absorbing barbed suture showed a complication profile equivalent to the smooth suture, while the slow-absorbing barbed suture had a higher incidence of minor suture extrusion. Barbed sutures enabled faster dermal closure quicker than smooth sutures, with a comparable complication profile. 1.

77 FR 43089 - Evaluation of an Up-and-Down Procedure for Acute Dermal Systemic Toxicity Testing: Request for...

Science.gov (United States)

2012-07-23

... vivo acute dermal systemic toxicity tests. Corresponding acute oral LD 50 data for the same compounds....), estimated LD 50 , and incidence of death and other adverse effects. Background Information on ICCVAM and... tests. DATES: Nominations and test method data for the acute dermal and oral tests should be submitted...

Ultraviolet-B Protective Effect of Flavonoids from Eugenia caryophylata on Human Dermal Fibroblast Cells.

Science.gov (United States)

Patwardhan, Juilee; Bhatt, Purvi

2015-10-01

The exposure of skin to ultraviolet-B (UV-B) radiations leads to deoxyribonucleic acid (DNA) damage and can induce production of free radicals which imbalance the redox status of the cell and lead to increased oxidative stress. Clove has been traditionally used for its analgesic, anti-inflammatory, anti-microbial, anti-viral, and antiseptic effects. To evaluate the UV-B protective activity of flavonoids from Eugenia caryophylata (clove) buds on human dermal fibroblast cells. Protective ability of flavonoid-enriched (FE) fraction of clove was studied against UV-B induced cytotoxicity, anti-oxidant regulation, oxidative DNA damage, intracellular reactive oxygen species (ROS) generation, apoptotic morphological changes, and regulation of heme oxygenase-1 (HO-1) gene through nuclear factor E2-related factor 2 antioxidant response element (Nrf2 ARE) pathway. FE fraction showed a significant antioxidant potential. Pretreatment of cells with FE fraction (10-40 μg/ml) reversed the effects of UV-B induced cytotoxicity, depletion of endogenous enzymatic antioxidants, oxidative DNA damage, intracellular ROS production, apoptotic changes, and overexpression of Nrf2 and HO-1. The present study demonstrated for the first time that the FE fraction from clove could confer UV-B protection probably through the Nrf2-ARE pathway, which included the down-regulation of Nrf2 and HO-1. These findings suggested that the flavonoids from clove could potentially be considered as UV-B protectants and can be explored further for its topical application to the area of the skin requiring protection. Pretreatment of human dermal fibroblast with flavonoid-enriched fraction of Eugenia caryophylata attenuated effects of ultraviolet-B radiationsIt also conferred protection through nuclear factor E2-related factor 2-antioxidant response pathway and increased tolerance of cells against oxidative stressFlavonoid-enriched fraction can be explored further for topical application to the skin as a

Differential activation behavior of dermal dendritic cells underlies the strain-specific Th1 responses to single epicutaneous immunization.

Science.gov (United States)

Lee, Chih-Hung; Chen, Jau-Shiuh; Chiu, Hsien-Ching; Hong, Chien-Hui; Liu, Ching-Yi; Ta, Yng-Cun; Wang, Li-Fang

2016-12-01

Epicutaneous immunization with allergens is an important sensitization route for atopic dermatitis. We recently showed in addition to the Th2 response following single epicutaneous immunization, a remarkable Th1 response is induced in B6 mice, but not in BALB/c mice, mimicking the immune response to allergens in human non-atopics and atopics. We investigated the underlying mechanisms driving this differential Th1 response between BALB/c and B6 mice. We characterized dermal dendritic cells by flow cytometric analysis. We measured the induced Th1/Th2 responses by measuring the IFN-γ/IL-13 contents of supernatants of antigen reactivation cultures of lymph node cells. We demonstrate that more dermal dendritic cells with higher activation status migrate into draining lymph nodes of B6 mice compared to BALB/c mice. Dermal dendritic cells of B6 mice have a greater ability to capture protein antigen than those of BALB/c mice. Moreover, increasing the activation status or amount of captured antigen in dermal dendritic cells induced a Th1 response in BALB/c mice. Further, differential activation behavior, but not antigen-capturing ability of dermal dendritic cells between BALB/c and B6 mice is dendritic cell-intrinsic. These results show that the differential activation behavior of dermal dendritic cells underlies the strain-specific Th1 responses following single epicutaneous immunization. Furthermore, our findings highlight the potential differences between human atopics and non-atopics and provide useful information for the prediction and prevention of atopic diseases. Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Dermal Exposure to Jet Fuel JP-8 Significantly Contributes to the Production of Urinary Naphthols in Fuel-Cell Maintenance Workers

OpenAIRE

Chao, Yi-Chun E.; Kupper, Lawrence L.; Serdar, Berrin; Egeghy, Peter P.; Rappaport, Stephen M.; Nylander-French, Leena A.

2005-01-01

Jet propulsion fuel 8 (JP-8) is the major jet fuel used worldwide and has been recognized as a major source of chemical exposure, both inhalation and dermal, for fuel-cell maintenance workers. We investigated the contributions of dermal and inhalation exposure to JP-8 to the total body dose of U.S. Air Force fuel-cell maintenance workers using naphthalene as a surrogate for JP-8 exposure. Dermal, breathing zone, and exhaled breath measurements of naphthalene were obtained using tape-strip sam...

A decision support framework for characterizing and managing dermal exposures to chemicals during Emergency Management and Operations.

Science.gov (United States)

Dotson, G Scott; Hudson, Naomi L; Maier, Andrew

2015-01-01

Emergency Management and Operations (EMO) personnel are in need of resources and tools to assist in understanding the health risks associated with dermal exposures during chemical incidents. This article reviews available resources and presents a conceptual framework for a decision support system (DSS) that assists in characterizing and managing risk during chemical emergencies involving dermal exposures. The framework merges principles of three decision-making techniques: 1) scenario planning, 2) risk analysis, and 3) multicriteria decision analysis (MCDA). This DSS facilitates dynamic decision making during each of the distinct life cycle phases of an emergency incident (ie, preparedness, response, or recovery) and identifies EMO needs. A checklist tool provides key questions intended to guide users through the complexities of conducting a dermal risk assessment. The questions define the scope of the framework for resource identification and application to support decision-making needs. The framework consists of three primary modules: 1) resource compilation, 2) prioritization, and 3) decision. The modules systematically identify, organize, and rank relevant information resources relating to the hazards of dermal exposures to chemicals and risk management strategies. Each module is subdivided into critical elements designed to further delineate the resources based on relevant incident phase and type of information. The DSS framework provides a much needed structure based on contemporary decision analysis principles for 1) documenting key questions for EMO problem formulation and 2) a method for systematically organizing, screening, and prioritizing information resources on dermal hazards, exposures, risk characterization, and management.

Species Typing in Dermal Leishmaniasis

Science.gov (United States)

Dujardin, Jean-Claude

2015-01-01

SUMMARY Leishmania is an infectious protozoan parasite related to African and American trypanosomes. All Leishmania species that are pathogenic to humans can cause dermal disease. When one is confronted with cutaneous leishmaniasis, identification of the causative species is relevant in both clinical and epidemiological studies, case management, and control. This review gives an overview of the currently existing and most used assays for species discrimination, with a critical appraisal of the limitations of each technique. The consensus taxonomy for the genus is outlined, including debatable species designations. Finally, a numerical literature analysis is presented that describes which methods are most used in various countries and regions in the world, and for which purposes. PMID:25672782

In vivo dermal absorption of pyrethroid pesticides in the rat.

Science.gov (United States)

The potential for exposure to pyrethroid pesticides has risen recently because of their increased use. The objective of this study was to examine the in vivo dermal absorption of bifenthrin, deltamethrin and permethrin in the rat. Hair on the dorsal side of anesthetized adult m...

Dermal uptake of nicotine from air and clothing: Experimental verification

DEFF Research Database (Denmark)

Bekö, Gabriel; Morrison, Glenn; Weschler, Charles J.

2017-01-01

Studies suggest that dermal uptake of certain semivolatile organic compounds (SVOC) directly from air can be a significant exposure pathway. This has been experimentally confirmed for two phthalates (Weschler et al., 2015). Morrison et al. (2016) showed that clean clothing can impede, while cloth...

Dermal toxicity of Colloidal Nanosilver in Albino Rabbit: A New Approach to Physicochemical Properties

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Anoushe Raesian

2017-09-01

Full Text Available Objective(s: Silver nanoparticles have been widely used as new potent antimicrobial agents in cosmetic and hygienic products, as well as in new medical devices. Serious concerns have been expressed on the potential health risks of dermal applications of nanosilver containing consumer products (AgNPs, therefore regulatory health risk assessment has become necessary for the safe usage of AgNPs in biomedical products with special emphasis to their dermal toxicity potentials. We aimed in the present study to compare the dermal toxicity of three different AgNP containing disinfectantsin an albino rabbit model and tried to determine the role of size and other physicochemical properties on their possible dermal toxicity. Methods: After the characterization of all three samples by transmission electron microscopy (TEM, X-Ray Diffraction (XRD and Dynamic Light Scattering (DLS , corrosive and irritant potentials  of AgNPs in three different sizes of three colloidal AgNPs were scored by the OECD 404 guideline with necessary modifications and were applied under the specified concentrations via nanosilver skin patches on the shaved skin of young female albino rabbits. All skin reactions were recorded in 3 min as well as in 1, 4, 24, 48 and 72 hours from the application and compared with the control group and followed up for 14 days. Results: Although short-term observations didn’t show any significant changes in the weight of animals and macroscopic  variables, long-term histopathological abnormalities were seen in the skin of all test groups, which was not associated with the size and other physicochemical properties of AgNP samples. The toxicity manifestations were dry skin, scaling in doses lower than 100 ppm and erythema in higher doses up to 4000 ppm which was reversed. Conclusions: This finding creates a new issue in the possible dermal effects of all colloidal AgNPs, containing nano health products, which should be considered in future studies by

Advective and diffusive dermal processes for estimating terrestrial amphibian pesticide exposure

Science.gov (United States)

Background/Question/Methods Dermal exposure presents a potentially significant but understudied route for pesticide uptake in terrestrial amphibians. Historically, evaluation of pesticide risk to both amphibians and reptiles has been achieved by comparing ingestion and inhalat...

Preventing the Complications Associated with the Use of Dermal Fillers in Facial Aesthetic Procedures: An Expert Group Consensus Report.

Science.gov (United States)

Urdiales-Gálvez, Fernando; Delgado, Nuria Escoda; Figueiredo, Vitor; Lajo-Plaza, José V; Mira, Mar; Ortíz-Martí, Francisco; Del Rio-Reyes, Rosa; Romero-Álvarez, Nazaret; Del Cueto, Sofía Ruiz; Segurado, María A; Rebenaque, Cristina Villanueva

2017-06-01

The use of dermal fillers in minimally invasive facial aesthetic procedures has become increasingly popular of late, yet as the indications and the number of procedures performed increase, the number of complications is also likely to increase. Paying special attention to specific patient characteristics and to the technique used can do much to avoid these complications. Indeed, a well-trained physician can also minimize the impact of such problems when they do occur. A multidisciplinary group of experts in aesthetic treatments reviewed the main factors associated with the complications that arise when using dermal fillers. A search of English, French and Spanish language articles in PubMed was performed using the terms "complications" OR "soft filler complications" OR "injectable complications" AND "dermal fillers". An initial document was drafted that reflected the complications identified and recommendations as to how they should be handled. This document was then reviewed and modified by the expert panel, until a final text was agreed upon and validated. The panel addressed consensus recommendations about the preparation, the procedure and the post-procedural care. The panel considered it crucial to obtain an accurate medical history to prevent potential complications. An additional clinical assessment, including standardized photography, is also crucial to evaluate the outcomes and prevent potential complications. Furthermore, the state of the operating theatre, the patient's health status and the preparation of the skin are critical to prevent superficial soft tissue infections. Finally, selecting the appropriate technique, based on the physician's experience, as well as the characteristics of the patient and filler, helps to ensure successful outcomes and limits the complications. This consensus document provides key elements to help clinicians who are starting to use dermal fillers to employ standard procedures and to understand how best to prevent

PDGF-AA-induced filamentous mitochondria benefit dermal papilla cells in cellular migration.

Science.gov (United States)

Mifude, C; Kaseda, K

2015-06-01

Human dermal papilla cells (HDPCs) play essential roles in hair follicular morphogenesis and postnatal hair growth cycles. Previous reports demonstrated that platelet-derived growth factor-AA (PDGF-AA) enhanced the formation of dermal condensates in hair follicular development. Additionally, PDGF-AA induces/maintains the anagen phase of the hair cycle. It is likely that mitochondrial morphology and functions are tightly coupled with maintenance of these energy-demanding activities. However, little is known about the mitochondrial regulation in HDPCs. Thus, we investigated the PDGF-involved mitochondrial regulation in HDPCs. The mitochondrial morphologies of HDPCs were examined in the presence or absence of PDGF-AA under a fluorescent microscope. ATP production and cellular motility were investigated. The relationship between mitochondrial morphology and the cellular functions was discussed. We observed that primary HDPCs contained mitochondria with filamentous and/or rounded morphologies. Both types of mitochondria showed similar membrane potentials. Interestingly, in the presence of PDGF-AA, but not PDGF-BB, the balance between the two morphologies shifted towards the filamentous form. Concomitantly, both mitochondrial enzymatic activity and total cellular ATP level were augmented by PDGF-AA. These two parameters were closely correlated, suggesting the mitochondrial involvement in the PDGF-augmented ATP production. Moreover, PDGF-AA accelerated the migration of HDPCs in a gap-filling assay, but did not change the rate of cellular proliferation. Notably, filamentous mitochondria dominated migrating HDPCs. PDGF-AA benefits HDPCs in the process of migration, by increasing the number of filamentous mitochondria. © 2014 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Dissecting antigen processing and presentation routes in dermal vaccination strategies

NARCIS (Netherlands)

Platteel, Anouk C M; Henri, Sandrine; Zaiss, Dietmar M; Sijts, Alice J A M

2017-01-01

The skin is an attractive site for vaccination due to its accessibility and presence of immune cells surveilling this barrier. However, knowledge of antigen processing and presentation upon dermal vaccination is sparse. In this study we determined antigen processing routes that lead to CD8(+) T cell

Radiological impact of the use of calcium hydroxylapatite dermal fillers

International Nuclear Information System (INIS)

Feeney, J.N.; Fox, J.J.; Akhurst, T.

2009-01-01

Aim: To report a case series in which the radiological features of the subcutaneous use of calcium hydroxylapatite (CaHa) dermal fillers are described for the first time. Materials and methods: Five patients with facial hyperattenuating hypermetabolic subcutaneous lesions were identified on 2- [ 18 F]-fluoro-2-deoxy-D-glucose (FDG) positron-emission tomography/computed tomography (PET/CT), who gave a history of facial injections to augment physical appearance. Correlation with additional imaging studies was performed. Results: All cases had subcutaneous high attenuation material on CT (range 280-700 HU), which was FDG avid on PET, with a standardized uptake value (SUV) range of 2.9-13.4. Magnetic resonance imaging (MRI) demonstrated a heterogeneous intermediate signal intensity subcutaneous lesion with enhancement post-gadolinium in one case. Conclusions: CaHa dermal filler is hyperattenuating on CT, hypermetabolic on FDG-PET imaging, of intermediate signal intensity on MRI, and is a potential cause of a false-positive imaging study.

Dermal Exposure Assessment to Pesticides in Farming Systems in Developing Countries: Comparison of Models

Directory of Open Access Journals (Sweden)

Camilo Lesmes Fabian

2015-04-01

Full Text Available In the field of occupational hygiene, researchers have been working on developing appropriate methods to estimate human exposure to pesticides in order to assess the risk and therefore to take the due decisions to improve the pesticide management process and reduce the health risks. This paper evaluates dermal exposure models to find the most appropriate. Eight models (i.e., COSHH, DERM, DREAM, EASE, PHED, RISKOFDERM, STOFFENMANAGER and PFAM were evaluated according to a multi-criteria analysis and from these results five models (i.e., DERM, DREAM, PHED, RISKOFDERM and PFAM were selected for the assessment of dermal exposure in the case study of the potato farming system in the Andean highlands of Vereda La Hoya, Colombia. The results show that the models provide different dermal exposure estimations which are not comparable. However, because of the simplicity of the algorithm and the specificity of the determinants, the DERM, DREAM and PFAM models were found to be the most appropriate although their estimations might be more accurate if specific determinants are included for the case studies in developing countries.

Quantitative and qualitative evaluation of dermal elastin of draught horses with chronic progressive lymphoedema.

Science.gov (United States)

De Cock, H E V; Van Brantegem, L; Affolter, V K; Oosterlinck, M; Ferraro, G L; Ducatelle, R

2009-01-01

Chronic progressive lymphoedema (CPL) in horses, a disease of certain draught breeds, is associated with altered elastin metabolism. The characteristic lesions are seen in the skin of the lower (distal) limbs. This study was based on horses of susceptible breeds, with and without CPL, and on horses of a non-susceptible breed. Skin samples were obtained for examination from the neck (considered a non-affected region) and from the distal limb. The skin lesions were characterized histologically and the dermal elastic fibres were evaluated morphologically and quantitatively. In all horses the mean elastin concentrations were highest in the superficial dermis, gradually decreasing in the mid-dermis and deep dermis. As compared with horses of a non-susceptible breed, affected horses had increased amounts of dermal elastin in both the distal limb and neck, while non-affected horses of a susceptible breed had decreased amounts. The findings support an earlier hypothesis that CPL of horses is a generalized disease. Reduced efficiency of the elastic network in supporting the dermal lymphatics may explain the development of CPL.

Cre/lox Studies Identify Resident Macrophages as the Major Source of Circulating Coagulation Factor XIII-A.

Science.gov (United States)

Beckers, Cora M L; Simpson, Kingsley R; Griffin, Kathryn J; Brown, Jane M; Cheah, Lih T; Smith, Kerrie A; Vacher, Jean; Cordell, Paul A; Kearney, Mark T; Grant, Peter J; Pease, Richard J

2017-08-01

To establish the cellular source of plasma factor (F)XIII-A. A novel mouse floxed for the F13a1 gene, FXIII-A flox/flox (Flox), was crossed with myeloid- and platelet-cre-expressing mice, and cellular FXIII-A mRNA expression and plasma and platelet FXIII-A levels were measured. The platelet factor 4-cre.Flox cross abolished platelet FXIII-A and reduced plasma FXIII-A to 23±3% ( P cre on plasma FXIII-A was exerted outside of the megakaryocyte lineage because plasma FXIII-A was not reduced in the Mpl -/- mouse, despite marked thrombocytopenia. In support of this, platelet factor 4-cre depleted FXIII-A mRNA in brain, aorta, and heart of floxed mice, where FXIII-A pos cells were identified as macrophages as they costained with CD163. In the integrin αM-cre.Flox and the double copy lysozyme 2-cre.cre.Flox crosses, plasma FXIII-A was reduced to, respectively, 75±5% ( P =0.003) and 30±7% ( P <0.001), with no change in FXIII-A content per platelet, further consistent with a macrophage origin of plasma FXIII-A. The change in plasma FXIII-A levels across the various mouse genotypes mirrored the change in FXIII-A mRNA expression in aorta. Bone marrow transplantation of FXIII-A +/+ bone marrow into FXIII-A -/- mice both restored plasma FXIII-A to normal levels and replaced aortic and cardiac FXIII-A mRNA, while its transplantation into FXIII-A +/+ mice did not increase plasma FXIII-A levels, suggesting that a limited population of niches exists that support FXIII-A-releasing cells. This work suggests that resident macrophages maintain plasma FXIII-A and exclude the platelet lineage as a major contributor. © 2017 The Authors.

Anti-PDGF receptor β antibody-conjugated squarticles loaded with minoxidil for alopecia treatment by targeting hair follicles and dermal papilla cells.

Science.gov (United States)

Aljuffali, Ibrahim A; Pan, Tai-Long; Sung, Calvin T; Chang, Shu-Hao; Fang, Jia-You

2015-08-01

This study developed lipid nanocarriers, called squarticles, conjugated with anti-platelet-derived growth factor (PDGF)-receptor β antibody to determine whether targeted Minoxidil (MXD) delivery to the follicles and dermal papilla cells (DPCs) could be achieved. Squalene and hexadecyl palmitate (HP) were used as the matrix of the squarticles. The PDGF-squarticles showed a mean diameter and zeta potential of 195 nm and -46 mV, respectively. Nanoparticle encapsulation enhanced MXD porcine skin deposition from 0.11 to 0.23 μg/mg. The antibody-conjugated nanoparticles ameliorated follicular uptake of MXD by 3-fold compared to that of the control solution in the in vivo mouse model. Both vertical and horizontal skin sections exhibited a wide distribution of nanoparticles in the follicles, epidermis, and deeper skin strata. The encapsulated MXD moderately elicited proliferation of DPCs and vascular endothelial growth factor (VEGF) expression. The active targeting of PDGF-squarticles may be advantageous to improving the limited success of alopecia therapy. Topical use of minoxidil is only one of the very few treatment options for alopecia. Nonetheless, the current delivery method is far from ideal. In this article, the authors developed lipid nanocarriers with anti-platelet-derived growth factor receptor ? antibody to target dermal papilla cells, and showed enhanced uptake of minoxidil. Copyright © 2015 Elsevier Inc. All rights reserved.

Acellular Dermal Matrix: Treating Periocular Melanoma in a Patient with Xeroderma Pigmentosa

Directory of Open Access Journals (Sweden)

Kamlen Pillay, MBChB

2017-08-01

Full Text Available We report a 7-year-old girl with xeroderma pigmentosum (XP, who presented in our clinic with a large melanoma (35 × 50 × 20 mm, Breslow depth 18 mm in the zygomatic-malar area. Palliative surgery was performed to maintain her residual vision and to reduce the pain caused by the compression of local structures. Because of the limited access of autologous skin grafts in pediatric patients with XP who are severely affected, we opted to use an acellular dermal matrix. There was 100% graft uptake, and the pain due to compression by the tumor was alleviated. This case demonstrates that acellular dermal matrices can be safely and effectively used in oncological facial reconstruction, especially in patients with progressive conditions such as XP.

Sensory evaluation and chemical analysis of exhaled and dermally emitted bioeffluents

DEFF Research Database (Denmark)

Tsushima, S.; Wargocki, Pawel; Tanabe, S.

2018-01-01

Conditions in which exhaled and dermally emitted bioeffluents could be sampled separately or together (whole-body emission) were created. Five lightly dressed males exhaled the air through a mask to another, identical chamber or without a mask to the chamber in which they were sitting; the outdoor......) was less acceptable, and the odor intensity was higher than when only exhaled bioeffluents were present. The presence or absence of exhaled bioeffluents in the unoccupied chamber made no significant difference to sensory assessments. At 28°C and with ozone present, the odor intensity increased and the PAQ...... was less acceptable in the chambers with whole-body bioeffluents. The concentrations of nonanal, decanal, geranylacetone, and 6-MHO were higher when dermally emitted bioeffluents were present; they increased further when ozone was present. The concentration of squalene then decreased and increased again...

In vitro dermal absorption of decabromodiphenyl ethane in rat and human skin

Data.gov (United States)

U.S. Environmental Protection Agency — In vitro dermal absorption of decabromodiphenyl ethane in rat and human skin. This dataset is associated with the following publication: Knudsen, G., J.M. Sanders,...

Endothelial network formed with human dermal microvascular endothelial cells in autologous multicellular skin substitutes.

Science.gov (United States)

Ponec, Maria; El Ghalbzouri, Abdoelwaheb; Dijkman, Remco; Kempenaar, Johanna; van der Pluijm, Gabri; Koolwijk, Pieter

2004-01-01

A human skin equivalent from a single skin biopsy harboring keratinocytes and melanocytes in the epidermal compartment, and fibroblasts and microvascular dermal endothelial cells in the dermal compartment was developed. The results of the study revealed that the nature of the extracellular matrix of the dermal compartments plays an important role in establishment of endothelial network in vitro. With rat-tail type I collagen matrices only lateral but not vertical expansion of endothelial networks was observed. In contrast, the presence of extracellular matrix of entirely human origin facilitated proper spatial organization of the endothelial network. Namely, when human dermal fibroblasts and microvascular endothelial cells were seeded on the bottom of an inert filter and subsequently epidermal cells were seeded on top of it, fibroblasts produced extracellular matrix throughout which numerous branched tubes were spreading three-dimensionally. Fibroblasts also facilitated the formation of basement membrane at the epidermal/matrix interface. Under all culture conditions, fully differentiated epidermis was formed with numerous melanocytes present in the basal epidermal cell layer. The results of the competitive RT-PCR revealed that both keratinocytes and fibroblasts expressed VEGF-A, -B, -C, aFGF and bFGF mRNA, whereas fibroblasts also expressed VEGF-D mRNA. At protein level, keratinocytes produced 10 times higher amounts of VEGF-A than fibroblasts did. The generation of multicellular skin equivalent from a single human skin biopsy will stimulate further developments for its application in the treatment of full-thickness skin defects. The potential development of biodegradable, biocompatible material suitable for these purposes is a great challenge for future research.

Reliability of a semi-quantitative method for dermal exposure assessment (DREAM)

NARCIS (Netherlands)

Wendel de Joode, B. van; Hemmen, J.J. van; Meijster, T.; Major, V.; London, L.; Kromhout, H.

2005-01-01

Valid and reliable semi-quantitative dermal exposure assessment methods for epidemiological research and for occupational hygiene practice, applicable for different chemical agents, are practically nonexistent. The aim of this study was to assess the reliability of a recently developed

Validation and comparison of two sampling methods to assess dermal exposure to drilling fluids and crude oil.

Science.gov (United States)

Galea, Karen S; McGonagle, Carolyn; Sleeuwenhoek, Anne; Todd, David; Jiménez, Araceli Sánchez

2014-06-01

Dermal exposure to drilling fluids and crude oil is an exposure route of concern. However, there have been no published studies describing sampling methods or reporting dermal exposure measurements. We describe a study that aimed to evaluate a wipe sampling method to assess dermal exposure to an oil-based drilling fluid and crude oil, as well as to investigate the feasibility of using an interception cotton glove sampler for exposure on the hands/wrists. A direct comparison of the wipe and interception methods was also completed using pigs' trotters as a surrogate for human skin and a direct surface contact exposure scenario. Overall, acceptable recovery and sampling efficiencies were reported for both methods, and both methods had satisfactory storage stability at 1 and 7 days, although there appeared to be some loss over 14 days. The methods' comparison study revealed significantly higher removal of both fluids from the metal surface with the glove samples compared with the wipe samples (on average 2.5 times higher). Both evaluated sampling methods were found to be suitable for assessing dermal exposure to oil-based drilling fluids and crude oil; however, the comparison study clearly illustrates that glove samplers may overestimate the amount of fluid transferred to the skin. Further comparison of the two dermal sampling methods using additional exposure situations such as immersion or deposition, as well as a field evaluation, is warranted to confirm their appropriateness and suitability in the working environment. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Dermal absorption and disposition of 1,3-diphenylguanidine in rats

International Nuclear Information System (INIS)

Shah, P.V.; Sumler, M.R.; Ioannou, Y.M.; Fisher, H.L.; Hall, L.L.

1985-01-01

Dermal absorption, distribution, and metabolism of 1,3-diphenylguanidine (CAS 102-06-7) (DPG), widely used as an accelerator in processing rubber and in food packaging, was studied in adult female Sprague-Dawley rats. DPG shows 10% penetration through clipped back skin of the rats in 5 d. The first-order dermal absorption rate constant as determined by least square method was 0.021 +/- 0.002 d -1 (T/sub 1/2/ = 33.6 d). Approximately 13% of the absorbed dose remained in the body in 5 d. Retention in skin, muscle, liver, intestine and fat contributed most to the body burden of DPG-derived radioactivity in 5 d. All tissues showed tissue to blood ratios greater than 1, with liver and intestine ratios of 26 at 5 d. Approximately 61% of the absorbed dose was eliminated into urine and 27% into feces in 5 d showing rapid clearance of absorbed DPG from the body. High-pressure liquid chromatography (HPLC) analysis of urine revealed two major peaks [parent compound metabolite(s)]. Within 72 h, approximately 50% of the DPG-derived radioactivity excreted in the urine was parent compound. After 72 h, the DPG-derived radioactivity in the urine was present in the form of a single metabolite, and no parent compound was detected. No parent compound was detected in feces. Two metabolites, neither of which occurred in urine, were detected in feces. The HPLC analysis of the radioactivity at the application site showed only parent compound. Even though DPG shows slow dermal penetration, this route of exposure needs to be considered in the risk assessments because of the suspected chronic toxicity of DPG

UVA Causes Dual Inactivation of Cathepsin B and L Underlying Lysosomal Dysfunction in Human Dermal Fibroblasts

Science.gov (United States)

Lamore, Sarah D.; Wondrak, Georg T.

2013-01-01

Cutaneous exposure to chronic solar UVA-radiation is a causative factor in photocarcinogenesis and photoaging. Recently, we have identified the thiol-dependent cysteine-protease cathepsin B as a novel UVA-target undergoing photo-oxidative inactivation upstream of autophagic-lysosomal dysfunction in fibroblasts. In this study, we examined UVA effects on a wider range of cathepsins and explored the occurrence of UVA-induced cathepsin inactivation in other cultured skin cell types. In dermal fibroblasts, chronic exposure to non-cytotoxic doses of UVA caused pronounced inactivation of the lysosomal cysteine-proteases cathepsin B and L, effects not observed in primary keratinocytes and occurring only to a minor extent in primary melanocytes. In order to determine if UVA-induced lysosomal impairment requires single or dual inactivation of cathepsin B and/or L, we used a genetic approach (siRNA) to selectively downregulate enzymatic activity of these target cathepsins. Monitoring an established set of protein markers (including LAMP1, LC3-II, and p62) and cell ultrastructural changes detected by electron microscopy, we observed that only dual genetic antagonism (targeting both CTSB and CTSL expression) could mimic UVA-induced autophagic-lysosomal alterations, whereas single knockdown (targeting CTSB or CTSL only) did not display ‘UVA-mimetic’ effects failing to reproduce the UVA-induced phenotype. Taken together, our data demonstrate that chronic UVA inhibits both cathepsin B and L enzymatic activity and that dual inactivation of both enzymes is a causative factor underlying UVA-induced impairment of lysosomal function in dermal fibroblasts. PMID:23603447

BIOCOMPATIBILITY AND TISSUE REGENERATING CAPACITY OF CROSS-LINKED DERMAL SHEEP COLLAGEN

NARCIS (Netherlands)

VANWACHEM, PB; VANLUYN, MJA; DAMINK, LHHO; DIJKSTRA, PJ; FEIJEN, J; NIEUWENHUIS, P

The biocompatibility and tissue regenerating capacity of four crosslinked dermal sheep collagens (DSC) was studied. In vitro, the four DSC versions were found to be noncytotoxic or very low in cytoxicity. After subcutaneous implantation in rats, hexamethylenediisocyanate-crosslinked DSC (HDSC)

DERMAL AND MOUTHING TRANSFERS OF SURFACE RESIDUES MEASURED USING FLUORESCENCE IMAGING

Science.gov (United States)

To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to develop and test methods for measuring...

Protective role for miR-9-5p in the fibrogenic transformation of human dermal fibroblasts.

Science.gov (United States)

Miguel, Verónica; Busnadiego, Oscar; Fierro-Fernández, Marta; Lamas, Santiago

2016-01-01

Excessive accumulation of extracellular matrix (ECM) proteins is the hallmark of fibrotic diseases, including skin fibrosis. This response relies on the activation of dermal fibroblasts that evolve into a pro-fibrogenic phenotype. One of the major players in this process is the cytokine transforming growth factor-β (TGF-β). MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate gene expression affecting a wide range of pathophysiological events including fibrogenesis. MicroRNA-9-5p (miR-9-5p) has been shown to exert a protective role in lung and peritoneal fibrosis. This study aimed to evaluate the role of miR-9-5p in skin fibrosis. miR-9-5p is up-regulated in TGF-β1-treated human dermal fibroblasts (HDFs). In silico identification of miR-9-5p targets spotted the type II TGF-β receptor (TGFBR2) as a potential TGF-β signaling-related effector for this miRNA. Consistently, over-expression of miR-9-5p in HDFs down-regulated TGFBR2 at both the mRNA and protein levels and reduced the phosphorylation of Smad2 and the translocation of Smad2/3 to the nucleus. In keeping, over-expression of miR-9-5p significantly delayed TGF-β1-dependent transformation of dermal fibroblasts, decreasing the expression of ECM protein collagen, type I, alpha 1 (Col1α1), and fibronectin (FN), the amount of secreted collagen proteins, and the expression of the archetypal myofibroblast marker alpha-smooth muscle actin (α-SMA). By contrast, specific inhibition of miR-9-5p resulted in enhanced presence of fibrosis markers. The expression of miR-9-5p was also detected in the skin and plasma in the mouse model of bleomycin-induced dermal fibrosis. Using lentiviral constructs, we demonstrated that miR-9-5p over-expression was also capable of deterring fibrogenesis in this same model. miR-9-5p significantly prevents fibrogenesis in skin fibrosis. This is mediated by an abrogation of TGF-β-mediated signaling through the down-regulation of TGFBR2 expression in HDFs

Dermatopharmacokinetic and pharmacodynamic evaluation of ethosomes of griseofulvin designed for dermal delivery

Energy Technology Data Exchange (ETDEWEB)

Aggarwal, Nidhi; Goindi, Shishu, E-mail: shishugoindi@yahoo.co.in [Panjab University, University Institute of Pharmaceutical Sciences (India)

2013-10-15

The present study is aimed at evaluation of the dermal delivery potential of griseofulvin-loaded ethosomes. Griseofulvin-loaded ethosomes were prepared using 'Cold technique' (Indian Patent Application 208/DEL/2009). The optimized formulation was characterized for vesicular shape and size, drug entrapment efficiency, drug content, pH, stability, and spreadability. Ex vivo skin permeation, dermatopharmacokinetics, and skin sensitivity studies were carried out using male Laca mice. In vivo antifungal activity was assessed against Microsporum canis using guinea pig model for dermatophytosis. The optimized formulation E7 possessing 2 % phospholipid (PL) and 30 % ethanol exhibited the highest drug entrapment (72.94 {+-} 0.80 %) and optimum vesicle size (148.5 {+-} 0.48 nm). E7 illustrated remarkably higher drug permeation and skin retention when compared with liposomes. Pharmacodynamic studies in guinea pigs induced with M. canis revealed that the dermal fungal infection was completely cured in 8 days upon twice daily topical application of griseofulvin-loaded ethosomes whereas liposomes led to complete cure in 14 days. The formulation was observed to be non-sensitizing, histopathologically safe, and stable at 5 {+-} 3, 25 {+-} 2, and 40 {+-} 2 Degree-Sign C for a period of 1 year. Results indicated that dermal delivery of griseofulvin employing ethosomes could be a commendable alternative to reduce the bio-burden associated with conventional oral formulations.

Chemical stabilization of polymers: Implications for dermal exposure to additives.

Science.gov (United States)

Bartsch, N; Girard, M; Schneider, L; Weijgert, V Van De; Wilde, A; Kappenstein, O; Vieth, B; Hutzler, C; Luch, A

2018-04-16

Technical benefits of additives in polymers stand in marked contrast to their associated health risks. Here, a multi-analyte method based on gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) was developed to quantify polymer additives in complex matrices such as low-density polyethylene (LDPE) and isolated human skin layers after dermal exposure ex vivo. That way both technical aspects and dermal exposure were investigated. The effects of polymer additivation on the material were studied using the example of LDPE. To this end, a tailor-made polymer was applied in aging studies that had been furnished with two different mixtures of phenol- and diarylamine-based antioxidants, plasticizers and processing aids. Upon accelerated thermo-oxidative aging of the material, the formation of LDPE degradation products was monitored with attenuated total reflectance-Fourier transformed infrared (ATR-FTIR) spectroscopy. Compared to pure LDPE, a protective effect of added antioxidants could be observed on the integrity of the polymer. Further, thermo-oxidative degradation of the additives and its kinetics were investigated using LDPE or squalane as matrix. The half-lives of additives in both matrices revealed significant differences between the tested additives as well as between LDPE and squalane. For instance, 2-tert-butyl-6-[(3-tert-butyl-2-hydroxy-5-methylphenyl)methyl]-4-methylphenol (Antioxidant 2246) showed a half-life 12 times lower when incorporated in LDPE as compared to squalane. As a model for dermal exposure of consumers, human skin was brought into contact with the tailor-made LDPE containing additives ex vivo in static Franz diffusion cells. The skin was then analyzed for additives and decomposition products. This study proved 10 polymer additives of diverse pysicochemical properties and functionalities to migrate out of the polymer and eventually overcome the intact human skin barrier during contact. Moreover, their individual distribution within

Dermal-epidermal membrane systems by using human keratinocytes and mesenchymal stem cells isolated from dermis

Energy Technology Data Exchange (ETDEWEB)

Salerno, Simona, E-mail: s.salerno@itm.cnr.it [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy); Messina, Antonietta [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy); Giordano, Francesca [Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, I-87036 Rende, (CS) (Italy); Bader, Augustinus [Biomedical-Biotechnological Center, BBZ, University of Leipzig, D-04103 Leipzig (Germany); Drioli, Enrico [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy); WCU Energy Engineering Department, Hanyang University, Seoul (Korea, Republic of); De Bartolo, Loredana, E-mail: l.debartolo@itm.cnr.it [Institute on Membrane Technology, National Research Council of Italy, ITM-CNR, c/o University of Calabria, via P. Bucci cubo 17/C, I-87036, Rende (CS) (Italy)

2017-02-01

Dermal-epidermal membrane systems were developed by co-culturing human keratinocytes with Skin derived Stem Cells (SSCs), which are Mesenchymal Stem Cells (MSCs) isolated from dermis, on biodegradable membranes of chitosan (CHT), polycaprolactone (PCL) and a polymeric blend of CHT and PCL. The membranes display physico-chemical, morphological, mechanical and biodegradation properties that could satisfy and fulfil specific requirements in skin tissue engineering. CHT membrane exhibits an optimal biodegradation rate for acute wounds; CHT-PCL for the chronic ones. On the other hand, PCL membrane in spite of its very slow biodegradation rate exhibits mechanical properties similar to in vivo dermis, a lower hydrophilic character, and a surface roughness, all properties that make it able to sustain cell adhesion and proliferation for in vitro skin models. Both CHT–PCL and PCL membranes guided epidermal and dermal differentiation of SSCs as pointed out by the expression of cytokeratins and the deposition of the ECM protein fibronectin, respectively. In the dermal-epidermal membrane systems, a more suitable microenvironment for the SSCs differentiation was promoted by the interactions and the mutual interplay with keratinocytes. Being skin tissue-biased stem cells committed to their specific final dermal and/or epidermal cell differentiation, SSCs are more suitable for skin tissue engineering than other adult MSCs with different origin. For this reason, they represent a useful autologous cell source for engineering skin substitutes for both in vivo and in vitro applications.

Laminin peptide YIGSR induces collagen synthesis in Hs27 human dermal fibroblasts

Energy Technology Data Exchange (ETDEWEB)

Yoon, Jong Hyuk; Kim, Jaeyoon; Lee, Hyeongjoo [NovaCell Technology Inc., Pohang, Kyungbuk 790-784 (Korea, Republic of); Kim, So Young [Department of Dermatology, Chung-Ang University College of Medicine, Seoul 156-756 (Korea, Republic of); Department of Convergence Medicine and Pharmaceutical Biosciences, Graduate School, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Jang, Hwan-Hee [Functional Food and Nutrition Division, Department of Agrofood Resources, Rural Development Administration, Suwon 441-853 (Korea, Republic of); Ryu, Sung Ho [Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk 790-784 (Korea, Republic of); Kim, Beom Joon [Department of Dermatology, Chung-Ang University College of Medicine, Seoul 156-756 (Korea, Republic of); Department of Convergence Medicine and Pharmaceutical Biosciences, Graduate School, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Lee, Taehoon G., E-mail: taehoon@novacelltech.com [NovaCell Technology Inc., Pohang, Kyungbuk 790-784 (Korea, Republic of)

2012-11-23

Highlights: Black-Right-Pointing-Pointer We identify a function of the YIGSR peptide to enhance collagen synthesis in Hs27. Black-Right-Pointing-Pointer YIGSR peptide enhanced collagen type 1 synthesis both of gene and protein levels. Black-Right-Pointing-Pointer There were no changes in cell proliferation and MMP-1 level in YIGSR treatment. Black-Right-Pointing-Pointer The YIGSR effect on collagen synthesis mediated activation of FAK, pyk2 and ERK. Black-Right-Pointing-Pointer The YIGSR-induced FAK and ERK activation was modulated by FAK and MEK inhibitors. -- Abstract: The dermal ECM is synthesized from fibroblasts and is primarily compromised of fibrillar collagen and elastic fibers, which support the mechanical strength and resiliency of skin, respectively. Laminin, a major glycoprotein located in the basement membrane, promotes cell adhesion, cell growth, differentiation, and migration. The laminin tyrosine-isoleucine-glycine-serine-arginine (YIGSR) peptide, corresponding to the 929-933 sequence of the {beta}1 chain, is known to be a functional motif with effects on the inhibition of tumor metastasis, the regulation of sensory axonal response and the inhibition of angiogenesis through high affinity to the 67 kDa laminin receptor. In this study, we identified a novel function of the YIGSR peptide to enhance collagen synthesis in human dermal fibroblasts. To elucidate this novel function regarding collagen synthesis, we treated human dermal fibroblasts with YIGSR peptide in both a time- and dose-dependent manner. According to subsequent experiments, we found that the YIGSR peptide strongly enhanced collagen type 1 synthesis without changing cell proliferation or cellular MMP-1 level. This YIGSR peptide-mediated collagen type 1 synthesis was modulated by FAK inhibitor and MEK inhibitor. This study clearly reveals that YIGSR peptide plays a novel function on the collagen type 1 synthesis of dermal fibroblasts and also suggests that YIGSR is a strong candidate

Dermal uptake of phthalates from clothing: comparison of model to human participant results

DEFF Research Database (Denmark)

Morrison, Glenn; Weschler, Charles J.; Bekö, Gabriel

2016-01-01

In this research, we extend a model of transdermal uptake of phthalates to include a layer of clothing. When compared with experimental results, this model better estimates dermal uptake of diethylphthalate (DEP) and di-n-butylphthalate (DnBP) than a previous model. It also demonstrates that uptake...... is sensitive to both the gap between skin and clothing and the time clothing is allowed to adsorb phthalates. The model predictions are consistent with the observation that exposed clothing increases dermal uptake when compared with uptake observed in bare-skin participants. Extension of this model beyond...... the cotton-phthalate system will be challenging until data on partition coefficients are quantified for other combinations of SVOCs, fabric materials and environmental conditions....

Burn injury suppresses human dermal dendritic cell and Langerhans cell function

NARCIS (Netherlands)

van den Berg, Linda M.; de Jong, Marein A. W. P.; Witte, Lot de; Ulrich, Magda M. W.; Geijtenbeek, Teunis B. H.

2011-01-01

Human skin contains epidermal Langerhans cells (LCs) and dermal dendritic cells (DCs) that are key players in induction of adaptive immunity upon infection. After major burn injury, suppressed adaptive immunity has been observed in patients. Here we demonstrate that burn injury affects adaptive

New experimental data on the human dermal absorption of Simazine and Carbendazim help to refine the assessment of human exposure.

Science.gov (United States)

Bányiová, Katarína; Nečasová, Anežka; Kohoutek, Jiří; Justan, Ivan; Čupr, Pavel

2016-02-01

Due to their widespread usage, people are exposed to pesticides on a daily basis. Although these compounds may have adverse effects on their health, there is a gap in the data and the methodology needed to reliably quantify the risks of non-occupational human dermal exposure to pesticides. We used Franz cells and human skin in order to measure the dermal absorption kinetics (steady-state flux, lag time and permeability coefficient) of Carbendazim and Simazine. These parameters were then used to refine the dermal exposure model and a probabilistic simulation was used to quantify risks resulting from exposure to pesticide-polluted waters. The experimentally derived permeability coefficient was 0.0034 cm h(-1) for Carbendazim and 0.0047 cm h(-1) for Simazine. Two scenarios (varying exposure duration and concentration, i.e. environmentally relevant and maximum solubility) were used to quantify the human health risks (hazard quotients) for Carbendazim and Simazine. While no risks were determined in the case of either scenario, the permeability coefficient, which is concentration independent and donor, formulation, compound and membrane specific, may be used in other scenarios and exposure models to quantify more precisely the dermally absorbed dose during exposure to polluted water. To the best of our knowledge, the dermal absorption kinetics parameters defined here are being published for the first time. The usage of experimental permeability parameters in combination with probabilistic risk assessment thus provides a new tool for quantifying the risks of human dermal exposure to pesticides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reepithelialization from stem cells of hair follicles of dermal graft of the scalp in acute treatment of third-degree burns: first clinical and histologic study.

Science.gov (United States)

Zakine, Gilbert; Mimoun, Maurice; Pham, Julien; Chaouat, Marc

2012-07-01

The scalp, an excellent donor site for thin skin grafts, presents a limited surface but is rich in keratinocyte stem cells. The purpose of this study was to double scalp harvesting in one procedure and to evaluate the capacity of the dermal layer to spontaneously reepithelialize from hair follicle stem cells. Two layers of 0.2-mm split-thickness skin graft, a dermoepidermal graft and a dermal graft, were harvested from scalp during the same procedure. Fifteen burn patients were included in this study. Healing of the scalp donor site and percentage of graft taken were evaluated. The Vancouver Scar Scale was used at 3 months and 1 year. Histologic studies were performed at day 0 and 3 months on grafts, and on the scalp at day 28. Nine patients were treated on the limbs with meshed dermal graft. Six were treated on the hands with unmeshed dermal graft. Graft take was good for both types of grafts. The mean time for scalp healing was 9.3 days. Histologic study confirmed that the second layer was a dermal graft with numerous annexes and that, at 3 months, the dermis had normal thickness but with rarer and smaller epidermal crests than dermal graft. The difference between the mean Vancouver Scar Scale score of dermal graft and dermoepidermal graft was not significant. The authors' study shows the efficacy of dermal graft from the scalp and good scalp healing. Therapeutic, II.

Enrichment of skin-derived neural precursor cells from dermal cell populations by altering culture conditions.

Science.gov (United States)

Bayati, Vahid; Gazor, Rohoullah; Nejatbakhsh, Reza; Negad Dehbashi, Fereshteh

2016-01-01

As stem cells play a critical role in tissue repair, their manipulation for being applied in regenerative medicine is of great importance. Skin-derived precursors (SKPs) may be good candidates for use in cell-based therapy as the only neural stem cells which can be isolated from an accessible tissue, skin. Herein, we presented a simple protocol to enrich neural SKPs by monolayer adherent cultivation to prove the efficacy of this method. To enrich neural SKPs from dermal cell populations, we have found that a monolayer adherent cultivation helps to increase the numbers of neural precursor cells. Indeed, we have cultured dermal cells as monolayer under serum-supplemented (control) and serum-supplemented culture, followed by serum free cultivation (test) and compared. Finally, protein markers of SKPs were assessed and compared in both experimental groups and differentiation potential was evaluated in enriched culture. The cells of enriched culture concurrently expressed fibronectin, vimentin and nestin, an intermediate filament protein expressed in neural and skeletal muscle precursors as compared to control culture. In addition, they possessed a multipotential capacity to differentiate into neurogenic, glial, adipogenic, osteogenic and skeletal myogenic cell lineages. It was concluded that serum-free adherent culture reinforced by growth factors have been shown to be effective on proliferation of skin-derived neural precursor cells (skin-NPCs) and drive their selective and rapid expansion.

Expanding the applications of Cadaveric skin - the properties and uses of an acellular dermal matrix

International Nuclear Information System (INIS)

Greenleaf, G.; Livesey, S.

1999-01-01

The ability to transplant organs and tissues has been one of the most significant advances of modern medicine. The availability of cadaveric allograft skin has greatly facilitated the practice of aggressive, early excision of massive burn injuries. Due to its ultimate rejection however, the role of allograft skin has historically been limited to that of a temporary wound dressing. Development of an acellular dermal allograft has greatly expanded the applications for donated human skin. AlloDerm(r) preserved dermal graft (LifeCell, The Woodlands, TX) is prepared via ionic separation of allograft skin followed by detergent removal of antigenic cells. Acellular dermal grafts are then cryoprotected and freeze-dried. The process maintains the structural integrity of the extracellular matrix and preserves the biochemical composition of the basement membrane. The resultant immunologically inert allograft can be used in a variety of applications. In burn injuries, lack of an adequate dermal component at either the donor or wound site may result in complications including contraction, delayed healing, hypertrophic scarring and keloid formation. Utilizing allogenic dermis eliminates the need for autologous dermis at the wound site and minimizes donor site trauma by allowing procurement of ultra-thin (0.006 ) autografts. Expanding the scope of traditional uses for allograft skin, acellular dermal grafts have been successfully utilized in a variety of procedures including duraplasty, orbital reconstruction, and hemia repar. In periodontal surgery, allograft tissue eliminates the need for painful palatal autografts and has been used to increase attached gingiva and reduce gingival recession. Resorption of autologous grafts or extrusion of synthetic material often hampers repair or reconstruction of soft tissue deficits. Transplantation of acellular allograft dermis provides a biochemically and structurally intact matrix, which persists and is ultimately repopulated with

Asiaticoside induces cell proliferation and collagen synthesis in human dermal fibroblasts

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Linda Yulianti

2015-08-01

Full Text Available Asiatiocoside, a saponin component isolated from Centella asiatica can improve wound healing by promoting the proliferation of human dermal fibroblasts (HDF and synthesis of collagen. The skin-renewing cells and type I and III collagen synthesis decrease with aging, resulting in the reduction of skin elasticity and delayed wound healing. Usage of natural active compounds from plants in wound healing should be evaluated and compared to retinoic acid as an active agent that regulates wound healing. The aim of this study was to compare and evaluate the effect of asiaticoside and retinoic acid to induce greater cell proliferation and type I and III collagen synthesis in human dermal fibroblast. Methods Laboratory experiments were conducted using human dermal fibroblasts (HDF isolated from human foreskin explants. Seven passages of HDF were treated with asiaticoside and retinoic acid at several doses and incubated for 24 and 48 hours. Cell viability in all groups was tested with the MTT assay to assess HDF proliferation. Type I and III collagen synthesis was examined using the respective ELISA kits. Analysis of variance was performed to compare the treatment groups. Results Asiaticoside had significantly stronger effects on HDF proliferation than retinoic acid (p<0.05. The type III collagen production was significantly greater induction with asiaticoside compared to retinoic acid (p<0.05. Conclusion Asiaticoside induces HDF proliferation and type I and III collagen synthesis in a time- and dose-dependent pattern. Asiaticoside has a similar effect as retinoic acid on type I and type III collagen synthesis.

Biological function evaluation and effects of laser micro-pore burn-denatured acellular dermal matrix.

Science.gov (United States)

Zhang, Youlai; Zeng, Yuanlin; Xin, Guohua; Zou, Lijin; Ding, Yuewei; Duyin, Jiang

2018-03-01

In the field of burns repairs, many problems exist in the shortage of donor skin, the expense of allograft or xenograft skin, temporary substitution and unsatisfactory extremity function after wound healing. Previous studies showed that burn-denatured skin could return to normal dermis formation and function. This study investigates the application of laser micro-pore burn-denatured acellular dermis matrix (DADM) from an escharotomy in the repair of burn wounds and evaluates the biological properties and wound repair effects of DADM in implantation experiments in Kunming mice. Specific-pathogen-free (SPF) Kunming mice were used in this study. A deep II° burn wound was created on the dorsum of the mice by an electric heated water bath. The full-thickness wound tissue was harvested. The necrotic tissue and subcutaneous tissue were removed. The denatured dermis was preserved and treated with 0.25% trypsin, 0.5% Triton X-100. The DADM was drilled by laser micro-pore. The biological properties and grafting effects of laser micro-pore burn-DADM were evaluated by morphology, cytokine expression levels and subcutaneous implantation experiments in Kunming mice. We found statistical significance (Ppore burn-DADM (experimental group) compared to the control group (no laser micro-pore burn-DADM). Cytokine expression level was different in the dermal matrixes harvested at various time points after burn (24h, 48h, 72h and infected wound group). Comparing the dermal matrix from 24h burn tissue to infected wound tissue, the expression level of IL-6, MMP-24, VE-cadherin and VEGF were decreased. We found no inflammatory cells infiltration in the dermal matrix were observed in both experimental and control groups (24h burn group), while the obviously vascular infiltration and fiber fusion were observed in the experimental group after subcutaneous implantation experiments. There was better bio-performance, low immunogenicity and better dermal incorporation after treated by laser

Regeneration of dermal patterns from the remaining pigments after surgery in Eublepharis macularius (a case report)

OpenAIRE

Nakashima, Noriyuki

2016-01-01

Background: Dermal injury of the Eublepharis macularius (leopard gecko) often results in a loss of the spotted patterns. The scar is usually well recovered, but the spots and the tubercles may be lost depending on the size and part of the lesion. This report presents a surgical attempting, in which the pigments in the edge of the remaining skin flap are partially preserved to maximally restore the natural pigmentation patterns during the course of dermal regeneration. Case presentation: A fou...

Measurements of dermal uptake of nicotine directly from air and clothing

DEFF Research Database (Denmark)

Beko, G.; Morrison, G.; Weschler, Charles J.

2017-01-01

In this preliminary study, we have investigated whether dermal uptake of nicotine directly from air or indirectly from clothing can be a meaningful exposure pathway. Two participants wearing only shorts and a third participant wearing clean cotton clothes were exposed to environmental tobacco smo...

Operator dermal exposure and protection provided by personal protective equipment and working coveralls during mixing/loading, application and sprayer cleaning in vineyards.

Science.gov (United States)

Thouvenin, Isabelle; Bouneb, Françoise; Mercier, Thierry

2017-06-01

The efficiency of a working coverall combined with personal protective equipment to protect operators against dermal exposure to plant protection products under field conditions was studied. Operators wore a non-certified water-repellent finish polyester/cotton coverall plus a certified gown during the mixing/loading and the cleaning phases. Insecticide foliar application to a vineyard was selected as the exposure scenario. The overall dermal residue levels measured in this study were in the range of data recently collected in Europe. The water-repellent finish working coverall reduced body exposure by a factor of approximately 95%. Wearing a Category III Type 3 partial body gown during mixing/loading and cleaning of the application equipment led to a further protective effect of 98.7%. The combination of a water-repellent finish working coverall and partial body protection during specific tasks provided satisfactory levels of protection and can be considered as suitable protection for the conditions of use studied.

Biocompatible polymer microneedle for topical/dermal delivery of tranexamic acid.

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A Machekposhti, S; Soltani, M; Najafizadeh, P; Ebrahimi, S A; Chen, P

2017-09-10

Recently-introduced biocompatible polymeric microneedles offer an efficient method for drug delivery. Tranexamic acid is a novel drug for treating melasma that is administered both locally and orally and inhibits excessive melanin via melanocyte. The tranexamic acid biocompatible polymer microneedle used in this study was fabricated from PVP and methacrylic acid, using the lithography method. The required mechanical strength to pierce skin was attained by optimizing the ratio of PVP to methacrylic acid. Acute dermal toxicity was done, and drug diffusion in skin layers was simulated by calculating the diffusion coefficient of tranexamic acid in interstitial fluid (plasma). The biocompatible polymer microneedle was fabricated at 60°C. Needles could sustain 0.6N that is enough to pierce stratum corneum. 34% of the released drug was locally effective and the rest permeated through the skin. The pyramidal polymer microneedle in this study was fully released in skin in approx. 7h. This polymer microneedle has no dermal toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

A physiological toxicokinetic model for dermal absorption of waterborne pyrene by trout

Energy Technology Data Exchange (ETDEWEB)

Namdari, R.; Law, F.C.P. [Simon Fraser Univ., Burnaby, British Columbia (Canada)

1995-12-31

A physiologically-based toxicokinetic (PB-TK) model was developed to describe the disposition of pyrene in trout following a bolus injection into the dorsal aorta. In the present study, the PB-TK model was adapted for dermal absorption of waterborne pyrene by trout. A skin compartment with transdermal flux described mathematically by the permeability-area-concentration product was added to the PB-TK model to allow prediction of pyrene concentrations in target organs and blood on the basis of exposure concentration at the skin surface. Physiologically relevant parameters e.g., organ volume, blood flow rate, and tissue/blood partitioning coefficient which were derived from the model were similar to those reported in the previous publication. The dermal PB-TK model was validated by exposing the trunk of trout (400--500 g) to stagnant water containing 24 ppm pyrene in a specially designed chamber for 4 hr, 24 hr or 48 hr. The trout were sacrificed at the conclusion of pyrene exposure and the tissues analyzed for unchanged pyrene by HPLC. In separate experiments, trout were implanted with dorsal aorta cannuli before the trunks were exposed to stagnant water containing 24 ppm pyrene in the chamber for 4 hr. At specific time intervals during and after pyrene exposure, blood samples were withdrawn through the cannula and analyzed for pyrene by HPLC. The agreement between simulated and experimentally obtained values shows that this model is an appropriate tool to predict dermal absorption of waterborne pyrene by trout.

Differentiation of human multipotent dermal fibroblasts into islet-like cell clusters

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Liu Wei

2010-06-01

Full Text Available Abstract Background We have previously obtained a clonal population of cells from human foreskin that is able to differentiate into mesodermal, ectodermal and endodermal progenies. It is of great interest to know whether these cells could be further differentiated into functional insulin-producing cells. Results Sixty-one single-cell-derived dermal fibroblast clones were established from human foreskin by limiting dilution culture. Of these, two clones could be differentiated into neuron-, adipocyte- or hepatocyte-like cells under certain culture conditions. In addition, those two clones were able to differentiate into islet-like clusters under pancreatic induction. Insulin, glucagon and somatostatin were detectable at the mRNA and protein levels after induction. Moreover, the islet-like clusters could release insulin in response to glucose in vitro. Conclusions This is the first study to demonstrate that dermal fibroblasts can differentiate into insulin-producing cells without genetic manipulation. This may offer a safer cell source for future stem cell-based therapies.

Biomaterials as novel penetration enhancers for transdermal and dermal drug delivery systems.

Science.gov (United States)

Chen, Yang; Wang, Manli; Fang, Liang

2013-01-01

The highly organized structure of the stratum corneum provides an effective barrier to the drug delivery into or across the skin. To overcome this barrier function, penetration enhancers are always used in the transdermal and dermal drug delivery systems. However, the conventional chemical enhancers are often limited by their inability to delivery large and hydrophilic molecules, and few to date have been routinely incorporated into the transdermal formulations due to their incompatibility and local irritation issues. Therefore, there has been a search for the compounds that exhibit broad enhancing activity for more drugs without producing much irritation. More recently, the use of biomaterials has emerged as a novel method to increase the skin permeability. In this paper, we present an overview of the investigations on the feasibility and application of biomaterials as penetration enhancers for transdermal or dermal drug delivery systems.

Dissolving Microneedle Patches for Dermal Vaccination.

Science.gov (United States)

Leone, M; Mönkäre, J; Bouwstra, J A; Kersten, G

2017-11-01

The dermal route is an attractive route for vaccine delivery due to the easy skin accessibility and a dense network of immune cells in the skin. The development of microneedles is crucial to take advantage of the skin immunization and simultaneously to overcome problems related to vaccination by conventional needles (e.g. pain, needle-stick injuries or needle re-use). This review focuses on dissolving microneedles that after penetration into the skin dissolve releasing the encapsulated antigen. The microneedle patch fabrication techniques and their challenges are discussed as well as the microneedle characterization methods and antigen stability aspects. The immunogenicity of antigens formulated in dissolving microneedles are addressed. Finally, the early clinical development is discussed.

Altered dynamics in the circadian oscillation of clock genes in dermal fibroblasts of patients suffering from idiopathic hypersomnia.

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Julian Lippert

Full Text Available From single cell organisms to the most complex life forms, the 24-hour circadian rhythm is important for numerous aspects of physiology and behavior such as daily periodic fluctuations in body temperature and sleep-wake cycles. Influenced by environmental cues - mainly by light input -, the central pacemaker in the thalamic suprachiasmatic nuclei (SCN controls and regulates the internal clock mechanisms which are present in peripheral tissues. In order to correlate modifications in the molecular mechanisms of circadian rhythm with the pathophysiology of idiopathic hypersomnia, this study aimed to investigate the dynamics of the expression of circadian clock genes in dermal fibroblasts of idiopathic hypersomniacs (IH in comparison to those of healthy controls (HC. Ten clinically and polysomnographically proven IH patients were recruited from the department of sleep medicine of the University Hospital of Muenster. Clinical diagnosis was done by two consecutive polysomnographies (PSG and Multiple Sleep Latency Test (MSLT. Fourteen clinical healthy volunteers served as control group. Dermal fibroblasts were obtained via punch biopsy and grown in cell culture. The expression of circadian clock genes was investigated by semiquantitative Reverse Transcriptase-PCR qRT-PCR analysis, confirming periodical oscillation of expression of the core circadian clock genes BMAL1, PER1/2 and CRY1/2. The amplitude of the rhythmically expressed BMAL1, PER1 and PER2 was significantly dampened in dermal fibroblasts of IH compared to HC over two circadian periods whereas the overall expression of only the key transcriptional factor BMAL1 was significantly reduced in IH. Our study suggests for the first time an aberrant dynamics in the circadian clock in IH. These findings may serve to better understand some clinical features of the pathophysiology in sleep - wake rhythms in IH.

Altered dynamics in the circadian oscillation of clock genes in dermal fibroblasts of patients suffering from idiopathic hypersomnia.

Science.gov (United States)

Lippert, Julian; Halfter, Hartmut; Heidbreder, Anna; Röhr, Dominik; Gess, Burkhard; Boentert, Mathias; Osada, Nani; Young, Peter

2014-01-01

From single cell organisms to the most complex life forms, the 24-hour circadian rhythm is important for numerous aspects of physiology and behavior such as daily periodic fluctuations in body temperature and sleep-wake cycles. Influenced by environmental cues - mainly by light input -, the central pacemaker in the thalamic suprachiasmatic nuclei (SCN) controls and regulates the internal clock mechanisms which are present in peripheral tissues. In order to correlate modifications in the molecular mechanisms of circadian rhythm with the pathophysiology of idiopathic hypersomnia, this study aimed to investigate the dynamics of the expression of circadian clock genes in dermal fibroblasts of idiopathic hypersomniacs (IH) in comparison to those of healthy controls (HC). Ten clinically and polysomnographically proven IH patients were recruited from the department of sleep medicine of the University Hospital of Muenster. Clinical diagnosis was done by two consecutive polysomnographies (PSG) and Multiple Sleep Latency Test (MSLT). Fourteen clinical healthy volunteers served as control group. Dermal fibroblasts were obtained via punch biopsy and grown in cell culture. The expression of circadian clock genes was investigated by semiquantitative Reverse Transcriptase-PCR qRT-PCR analysis, confirming periodical oscillation of expression of the core circadian clock genes BMAL1, PER1/2 and CRY1/2. The amplitude of the rhythmically expressed BMAL1, PER1 and PER2 was significantly dampened in dermal fibroblasts of IH compared to HC over two circadian periods whereas the overall expression of only the key transcriptional factor BMAL1 was significantly reduced in IH. Our study suggests for the first time an aberrant dynamics in the circadian clock in IH. These findings may serve to better understand some clinical features of the pathophysiology in sleep - wake rhythms in IH.

A case of cellulitis-like foreign body reaction after hyaluronic acid dermal filler injection

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Yo Sup Shin

2018-03-01

Full Text Available A 58-year-old female presented with 3 weeks history of painful skin lesion on the right cheek. Diagnosis was cellulitis based on the clinical manifestation and laboratory test. However, skin lesion did not improve with antibiotics, and as a consequence, biopsy was performed. Based on histopathological findings and additional information of her previous history of intradermal filler injection, the lesion was diagnosed to be foreign body reaction. Previous reported cases of foreign body reaction induced by hyaluronic acid dermal filler typically manifested as nodular lesions, but cellulitis-like cutaneous manifestation has not been reported. Therefore, we report this interesting case of foreign body reaction after hyaluronic acid dermal filler injection.

Default values for assessment of potential dermal exposure of the hands to industrial chemicals in the scope of regulatory risk assessments

NARCIS (Netherlands)

Marquart, H.; Warren, N.D.; Laitinen, J.; Hemmen, J.J. van

2006-01-01

Dermal exposure needs to be addressed in regulatory risk assessment of chemicals. The models used so far are based on very limited data. The EU project RISKOFDERM has gathered a large number of new measurements on dermal exposure to industrial chemicals in various work situations, together with

Improving reptile ecological risk assessment: oral and dermal toxicity of pesticides to a common lizard species (Sceloporus occidentalis).

Science.gov (United States)

Weir, Scott M; Yu, Shuangying; Talent, Larry G; Maul, Jonathan D; Anderson, Todd A; Salice, Christopher J

2015-08-01

Reptiles have been understudied in ecotoxicology, which limits consideration in ecological risk assessments. The goals of the present study were 3-fold: to improve oral and dermal dosing methodologies for reptiles, to generate reptile toxicity data for pesticides, and to correlate reptile and avian toxicity. The authors first assessed the toxicity of different dosing vehicles: 100 μL of water, propylene glycol, and acetone were not toxic. The authors then assessed the oral and dermal toxicity of 4 pesticides following the up-and-down procedure. Neither brodifacoum nor chlorothalonil caused mortality at doses ≤ 1750 μg/g. Under the "neat pesticide" oral exposure, endosulfan (median lethal dose [LD50] = 9.8 μg/g) was more toxic than λ-cyhalothrin (LD50 = 916.5 μg/g). Neither chemical was toxic via dermal exposure. An acetone dosing vehicle increased λ-cyhalothrin toxicity (oral LD50 = 9.8 μg/g; dermal LD50 = 17.5 μg/g), but not endosulfan. Finally, changes in dosing method and husbandry significantly increased dermal λ-cyhalothrin LD50s, which highlights the importance of standardized methods. The authors combined data from the present study with other reptile LD50s to correlate with available avian data. When only definitive LD50s were used in the analysis, a strong correlation was found between avian and reptile toxicity. The results suggest it is possible to build predictive relationships between avian and reptile LD50s. More research is needed, however, to understand trends associated with chemical classes and modes of action. © 2015 SETAC.

Acellular dermal matrix based nipple reconstruction: A modified technique

Directory of Open Access Journals (Sweden)

Raghavan Vidya

2017-09-01

Full Text Available Nipple areolar reconstruction (NAR has evolved with the advancement in breast reconstruction and can improve self-esteem and, consequently, patient satisfaction. Although a variety of reconstruction techniques have been described in the literature varying from nipple sharing, local flaps to alloplastic and allograft augmentation, over time, loss of nipple projection remains a major problem. Acellular dermal matrices (ADM have revolutionised breast reconstruction more recently. We discuss the use of ADM to act as a base plate and strut to give support to the base and offer nipple bulk and projection in a primary procedure of NAR with a local clover shaped dermal flap in 5 breasts (4 patients. We used 5-point Likert scales (1 = highly unsatisfied, 5 = highly satisfied to assess patient satisfaction. Median age was 46 years (range: 38–55 years. Nipple projection of 8 mm, 7 mm, and 7 mms were achieved in the unilateral cases and 6 mm in the bilateral case over a median 18 month period. All patients reported at least a 4 on the Likert scale. We had no post-operative complications. It seems that nipple areolar reconstruction [NAR] using ADM can achieve nipple projection which is considered aesthetically pleasing for patients.

Evaluation of 3D-human skin equivalents for assessment of human dermal absorption of some brominated flame retardants.

Science.gov (United States)

Abdallah, Mohamed Abou-Elwafa; Pawar, Gopal; Harrad, Stuart

2015-11-01

Ethical and technical difficulties inherent to studies in human tissues are impeding assessment of the dermal bioavailability of brominated flame retardants (BFRs). This is further complicated by increasing restrictions on the use of animals in toxicity testing, and the uncertainties associated with extrapolating data from animal studies to humans due to inter-species variations. To overcome these difficulties, we evaluate 3D-human skin equivalents (3D-HSE) as a novel in vitro alternative to human and animal testing for assessment of dermal absorption of BFRs. The percutaneous penetration of hexabromocyclododecanes (HBCD) and tetrabromobisphenol-A (TBBP-A) through two commercially available 3D-HSE models was studied and compared to data obtained for human ex vivo skin according to a standard protocol. No statistically significant differences were observed between the results obtained using 3D-HSE and human ex vivo skin at two exposure levels. The absorbed dose was low (less than 7%) and was significantly correlated with log Kow of the tested BFR. Permeability coefficient values showed increasing dermal resistance to the penetration of γ-HBCD>β-HBCD>α-HBCD>TBBPA. The estimated long lag times (>30 min) suggests that frequent hand washing may reduce human exposure to HBCDs and TBBPA via dermal contact. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vitro dermal absorption of pyrethroid pesticides in human and rat skin

International Nuclear Information System (INIS)

Hughes, Michael F.; Edwards, Brenda C.

2010-01-01

Dermal exposure to pyrethroid pesticides can occur during manufacture and application. This study examined the in vitro dermal absorption of pyrethroids using rat and human skin. Dermatomed skin from adult male Long Evans rats or human cadavers was mounted in flow-through diffusion cells, and radiolabeled bifenthrin, deltamethrin or cis-permethrin was applied in acetone to the skin. Fractions of receptor fluid were collected every 4 h. At 24 h, the skins were washed with soap and water to remove unabsorbed chemical. The skin was then solubilized. Two additional experiments were performed after washing the skin; the first was tape-stripping the skin and the second was the collection of receptor fluid for an additional 24 h. Receptor fluid, skin washes, tape strips and skin were analyzed for radioactivity. For rat skin, the wash removed 53-71% of the dose and 26-43% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid ranged from 1 to 5%. For human skin, the wash removed 71-83% of the dose and 14-25% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid was 1-2%. Tape-stripping removed 50-56% and 79-95% of the dose in rat and human skin, respectively, after the wash. From 24-48 h, 1-3% and about 1% of the dose diffused into the receptor fluid of rat and human skin, respectively. The pyrethroids bifenthrin, deltamethrin and cis-permethrin penetrated rat and human skin following dermal application in vitro. However, a skin wash removed 50% or more of the dose from rat and human skin. Rat skin was more permeable to the pyrethroids than human skin. Of the dose in skin, 50% or more was removed by tape-stripping, suggesting that permeation of pyrethroids into viable tissue could be impeded. The percentage of the dose absorbed into the receptor fluid was considerably less than the dose in rat and human skin. Therefore, consideration of the skin type used and fractions analyzed are important when using

A hyaluronic acid membrane delivery system for cultured keratinocytes: clinical "take" rates in the porcine kerato-dermal model.

Science.gov (United States)

Myers, S R; Grady, J; Soranzo, C; Sanders, R; Green, C; Leigh, I M; Navsaria, H A

1997-01-01

The clinical take rates of cultured keratinocyte autografts are poor on a full-thickness wound unless a dermal bed is provided. Even under these circumstances two important problems are the time delay in growing autografts and the fragility of the grafts. A laser-perforated hyaluronic acid membrane delivery system allows grafting at early confluence without requiring dispase digestion to release grafts from their culture dishes. We designed this study to investigate the influence of this membrane on clinical take rates in an established porcine kerato-dermal grafting model. The study demonstrated a significant reduction in take as a result of halving the keratinocyte seeding density onto the membrane. The take rates, however, of grafts grown on the membrane at half or full conventional seeding density and transplanted to a dermal wound bed were comparable, if not better, than those of keratinocyte sheet grafts.

Defense against dermal exposures is only skin deep

DEFF Research Database (Denmark)

Nielsen, Jesper Bo; Nielsen, Flemming; Sørensen, Jens Ahm

2007-01-01

study demonstrates that a limited damage to the skin significantly increases the permeability coefficient (K (p)) as well as total percutaneous penetration of chemicals, and most significantly for those compounds that due to their physicochemical characteristics (the most hydrophilic as well as the most...... compartments is affected by the physicochemical characteristics of the chemicals as well as by the integrity of the skin. This observation may have implications when evaluating the possibility of removing chemicals from the skin through different cleansing procedures following unintended dermal exposures....

Potential Dermal Exposure to Flonicamid and Risk Assessment of Applicators During Treatment in Apple Orchards.

Science.gov (United States)

Zhao, Mei-Ai; Yu, Aili; Zhu, Yong-Zhe; Kim, Jeong-Han

2015-01-01

Exposure and risk assessments of flonicamid for applicators were performed in apple orchards in Korea. Fifteen experiments were done with two experienced applicators under typical field conditions using a speed sprayer. In this study, cotton gloves, socks, masks, and dermal patches were used to monitor potential dermal exposure to flonicamid, and personal air samplers with XAD-2 resin and glass fiber filter were used to monitor potential inhalation exposure. The analytical methods were validated for the limit of detection, limit of quantitation, reproducibility, linearity of the calibration curve, and recovery of flonicamid from various exposure matrices. The results were encouraging and acceptable for an exposure study. The applicability of XAD-2 resin was evaluated via a trapping efficiency and breakthrough test. During the mixing/loading, the average total dermal exposure was 22.6 μg of flonicamid, corresponding to 4.5×10(-5)% of the prepared amount. For the spraying, the potential dermal exposure was 9.32 mg, and the ratio to applied amount was 1.9 × 10(-2%). The primary exposed body parts were the thigh (2.90 mg), upper arm (1.75 mg), and lower leg (1.66 mg). By comparison, absorbable quantity of exposure was small, only 1.62 μg (3.2×10(-6)%). The margin of safety (MOS) were calculated for risk assessment, in all sets of trials, MOS > 1, indicating the exposure level of flonicamid was considered to be safe in apple orchards. Although this was a limited study, it provided a good estimate of flonicamid exposure for orchard applicators.

In vitro bioaccessibility of copper azole following simulated dermal transfer from pressure-treated wood

Data.gov (United States)

U.S. Environmental Protection Agency — In vitro bioaccessibility of copper azole following simulated dermal transfer from pressure-treated wood. This dataset is associated with the following publication:...

Studies estimating the dermal bioavailability of polynuclear aromatic hydrocarbons from manufactured plant tar-contaminated soils

International Nuclear Information System (INIS)

Roy, T.A.; Krueger, A.J.; Taylor, B.B.; Mauro, D.M.; Goldstein, L.S.

1998-01-01

In vitro percutaneous absorption studies were performed with contaminated soils or organic extracts of contaminated soils collected at manufactured gas plant (MGP) sites. The MGP tar contaminated soils were found to contain a group of targeted polynuclear aromatic hydrocarbons (PAH) at levels ranging from 10 to 2400 mg/kg. The soil extracts contained target PAH at levels ranging from 12 000 - 34 000 mg/kg. Dermal penetration rates of target PAH from the MGP tar-contaminated soils/soil extracts were determined experimentally through human skin using 3 H-benzo(a)pyrene (BaP) as a surrogate. Results from three MGP sites showed reductions of 2-3 orders of magnitude in PAH absorption through human skin from the most contaminated soils in comparison to the soil extracts. Reduction in PAH penetration can be attributed to PAH concentration and (soil) matrix properties. PAH dermal flux values are used to determine site-specific dermally absorbed dose (DAD) and chronic daily intake (CDI) which are essential terms required to estimate risk associated with human exposure to MGP tar and MGP tar-contaminated soils. 21 refs., 4 figs., 3 tabs

Phacomatosis pigmento-pigmentaria: aberrant dermal melanocytosis and nevus spilus.

Science.gov (United States)

Wolf, Ronni; Ruocco, Eleonora; Baroni, Adone

2011-08-15

We present a dermal melanocytosis with superimposed nevus spilus on the arm of a 5-year-old boy. We recently introduced a new type of phacomatosis, which we termed "phacomatosis pigmentopigmentalis," that is analogous to phacomatosis pigmentokeratotica or pigmentovascularis, for describing the association of two pigmented nevi. The present case is an example of this type of phacomatosis, which now we prefer to define phacomatosis pigmento-pigmentaria according to the correct Latin terminology.

Effect of radiation on reconstitution of skin equivalent (dermal alterations); Effet de l`irradiation sur la reconstruction d`une peau equivalente (alterations dermiques)

Energy Technology Data Exchange (ETDEWEB)

Gentilhomme, E.; Bergier, J.; Richard, M.; Neveux, Y.

1994-12-31

Dermal equivalents have been treated by single doses of gamma irradiation of 10, 20, 30 and 50 Gray. Numerations at different times show a dose and time dependant diminution of cellular population. This diminution is histologically observed in dermal part of reconstituted skin, in association with cellular and functional alterations of fibroblast cells. Modifications of epidermal epithelia are also noted in some reconstituted skin. This model would be useful to apprehend the effect of a dermal irradiation lesion on the later epidermization. (author). 4 refs.

Coverage of Megaprosthesis with Human Acellular Dermal Matrix after Ewing's Sarcoma Resection: A Case Report

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Robert M. Whitfield

2011-01-01

Full Text Available A 23-year-old female with Ewing's Sarcoma underwent tibial resection and skeletal reconstruction using proximal tibial allograft prosthetic reconstruction with distal femur endoprosthetic reconstruction and rotating hinge. Human acellular dermal matrix, (Alloderm, LifeCell, Branchburg, NJ, USA, was used to wrap the skeletal reconstruction. Soft tissue reconstruction was completed with a rotational gastrocnemius muscle flap and skin graft. Despite prolonged immobilization, the patient quickly regained full range of motion of her skeletal reconstruction. Synthetic mesh, tapes and tubes are used to perform capsule reconstruction of megaprosthesis. This paper describes the role of human acellular dermal matrix in capsule reconstruction around a megaprosthesis.

The influence of water mixtures on the dermal absorption of glycol ethers

International Nuclear Information System (INIS)

Traynor, Matthew J.; Wilkinson, Simon C.; Williams, Faith M.

2007-01-01

Glycol ethers are solvents widely used alone and as mixtures in industrial and household products. Some glycol ethers have been shown to have a range of toxic effects in humans following absorption and metabolism to their aldehyde and acid metabolites. This study assessed the influence of water mixtures on the dermal absorption of butoxyethanol and ethoxyethanol in vitro through human skin. Butoxyethanol penetrated human skin up to sixfold more rapidly from aqueous solution (50%, 450 mg/ml) than from the neat solvent. Similarly penetration of ethoxyethanol was increased threefold in the presence of water (50%, 697 mg/ml). There was a corresponding increase in apparent permeability coefficient as the glycol ether concentration in water decreased. The maximum penetration rate of water also increased in the presence of both glycol ethers. Absorption through a synthetic membrane obeyed Fick's Law and absorption through rat skin showed a similar profile to human skin but with a lesser effect. The mechanisms for this phenomenon involves disruption of the stratum corneum lipid bilayer by desiccation by neat glycol ether micelles, hydration with water mixtures and the physicochemical properties of the glycol ether-water mixtures. Full elucidation of the profile of absorption of glycol ethers from mixtures is required for risk assessment of dermal exposure. This work supports the view that risk assessments for dermal contact scenarios should ideally be based on absorption data obtained for the relevant formulation or mixture and exposure scenario and that absorption derived from permeability coefficients may be inappropriate for water-miscible solvents

Determination of radiation exposure of humans due to dermal contact with radionuclides

International Nuclear Information System (INIS)

Pratzel, H.G.

1992-01-01

It is the aim of this research project to determine the distribution of radioactive substances in the skin and organism, in order to be able to predict from these data the radiation exposure to be expected following contamination of the skin with radionuclides. Further investigations are to be carried out into the suitability of measures of prevention and decontamination. In view of the fact that only small amounts of those compounds are absorbed by the skin, the determination of the parameters chosen was carried out in radionuclide studies in young pigs. With the exception of the skin of the palms and soles, the radiation effects in man could easily be extrapolated from the results of these experiments. The findings revealed permit the following conclusions to be drawn: The incorporation of radioactive substances after dermal contamination is quite unavoidable, even if this is immediately followed by decontamination measures. The degree of incorporation and resulting radiation dose are only minor and remain several orders of magnitude below the dermal radiation dose. If the skin is contaminated with radioactive liquids, the extent of incorporation and accumulation is proportionate to the activity concentration of those liquids. The incorporated radiation dose is in direct proportion to the contaminated skin area and also shows a relationship to the duration of contamination, if the skin is wet. The uptake by the organism may be somewhat reduced, if decontamination is initiated immediately. Dermal protectives may help to reduce skin permeability and, thus, the uptake of radioactivity into the corneal layer and follicles. (orig./MG) [de

Topical photodynamic therapy following excisional wounding of human skin increases production of transforming growth factor-β3 and matrix metalloproteinases 1 and 9, with associated improvement in dermal matrix organization.

Science.gov (United States)

Mills, S J; Farrar, M D; Ashcroft, G S; Griffiths, C E M; Hardman, M J; Rhodes, L E

2014-07-01

Animal studies report photodynamic therapy (PDT) to improve healing of excisional wounds; the mechanism is uncertain and equivalent human studies are lacking. To explore the impact of methyl aminolaevulinate (MAL)-PDT on clinical and microscopic parameters of human cutaneous excisional wound healing, examining potential modulation through production of transforming growth factor (TGF)-β isoforms. In 27 healthy older men (60-77 years), a 4-mm punch biopsy wound was created in skin of the upper inner arm and treated with MAL-PDT three times over 5 days. An identical control wound to the contralateral arm was untreated and both wounds left to heal by secondary intention. Wounds were re-excised during the inflammatory phase (7 days, n = 10), matrix remodelling (3 weeks, n = 8) and cosmetic outcome/dermal structure (9 months, n = 9). Production of TGF-β1, TGF-β3 and matrix metalloproteinases (MMPs) was assessed by immunohistochemistry alongside microscopic measurement of wound size/area and clinical assessment of wound appearance. MAL-PDT delayed re-epithelialization at 7 days, associated with increased inflammation. However, 3 weeks postwounding, treated wounds were smaller with higher production of MMP-1 (P = 0·01), MMP-9 (P = 0·04) and TGF-β3 (P = 0·03). TGF-β1 was lower than control at 7 days and higher at 3 weeks (both P = 0·03). At 9 months, MAL-PDT-treated wounds showed greater, more ordered deposition of collagen I, collagen III and elastin (all P < 0·05). MAL-PDT increases MMP-1, MMP-9 and TGF-β3 production during matrix remodelling, ultimately producing scars with improved dermal matrix architecture. © 2014 British Association of Dermatologists.

40 CFR 795.232 - Inhalation and dermal pharmacokinetics of commercial hexane.

Science.gov (United States)

2010-07-01

... studies of volatile solvents in hairless mice. I. Description of a skin depot”, In: Journal of Applied... concentration. (C) Dermal studies. The test substance shall be applied and kept on the skin for a minimum of 6... data shall be evaluated by appropriate statistical methods. (3) Reporting results. In addition to the...

Dermal application of nitric oxide releasing acidified nitrite-containing liniments significantly reduces blood pressure in humans.

Science.gov (United States)

Opländer, Christian; Volkmar, Christine M; Paunel-Görgülü, Adnana; Fritsch, Thomas; van Faassen, Ernst E; Mürtz, Manfred; Grieb, Gerrit; Bozkurt, Ahmet; Hemmrich, Karsten; Windolf, Joachim; Suschek, Christoph V

2012-02-15

Vascular ischemic diseases, hypertension, and other systemic hemodynamic and vascular disorders may be the result of impaired bioavailability of nitric oxide (NO). NO but also its active derivates like nitrite or nitroso compounds are important effector and signal molecules with vasodilating properties. Our previous findings point to a therapeutical potential of cutaneous administration of NO in the treatment of systemic hemodynamic disorders. Unfortunately, no reliable data are available on the mechanisms, kinetics and biological responses of dermal application of nitric oxide in humans in vivo. The aim of the study was to close this gap and to explore the therapeutical potential of dermal nitric oxide application. We characterized with human skin in vitro and in vivo the capacity of NO, applied in a NO-releasing acidified form of nitrite-containing liniments, to penetrate the epidermis and to influence local as well as systemic hemodynamic parameters. We found that dermal application of NO led to a very rapid and significant transepidermal translocation of NO into the underlying tissue. Depending on the size of treated skin area, this translocation manifests itself through a significant systemic increase of the NO derivates nitrite and nitroso compounds, respectively. In parallel, this translocation was accompanied by an increased systemic vasodilatation and blood flow as well as reduced blood pressure. We here give evidence that in humans dermal application of NO has a therapeutic potential for systemic hemodynamic disorders that might arise from local or systemic insufficient availability of NO or its bio-active NO derivates, respectively. Copyright © 2012 Elsevier Inc. All rights reserved.

RISKOFDERM: Risk Assessment of Occupational Dermal Exposure to Chemicals. An Introduction to a Series of Papers on the Development of a Toolkit

NARCIS (Netherlands)

Hemmen, J.J. van; Auffarth, J.; Evans, P.G.; Rajan-Sithamparanadarajah, B.; Marquart, H.; Oppl, R.

2003-01-01

Dermal exposure to industrial chemicals during work is of major concern in the risk assessment of chemicals. Current approaches in procedures for European legislation are not based on experimental data on dermal exposures in workplaces because these are lacking. A large project, with four

Finite element approach to study the behavior of fluid distribution in the dermal regions of human body due to thermal stress

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M.A. Khanday

2015-10-01

Full Text Available The human body is a complex structure where the balance of mass and heat transport in all tissues is necessary for its normal functioning. The stabilities of intracellular and extracellular fluids are important physiological factors responsible for homoeostasis. To estimate the effects of thermal stress on the behavior of extracellular fluid concentration in human dermal regions, a mathematical model based on diffusion equation along with appropriate boundary conditions has been formulated. Atmospheric temperature, evaporation rate, moisture concentration and other factors affecting the fluid concentration were taken into account. The variational finite element approach has been employed to solve the model and the results were interpreted graphically.

Mixture component effects on the in vitro dermal absorption of pentachlorophenol

Energy Technology Data Exchange (ETDEWEB)

Riviere, J.E.; Qiao, G.; Baynes, R.E.; Brooks, J.D. [Coll. of Veterinary Medicine, North Carolina State Univ., Raleigh, NC (United States); Mumtaz, M. [Agency for Toxic Substances and Disease Registry (ATSDR), Atlanta, GA (United States)

2001-08-01

Interactions between chemicals in a mixture and interactions of mixture components with the skin can significantly alter the rate and extent of percutaneous absorption, as well as the cutaneous disposition of a topically applied chemical. The predictive ability of dermal absorption models, and consequently the dermal risk assessment process, would be greatly improved by the elucidation and characterization of these interactions. Pentachlorophenol (PCP), a compound known to penetrate the skin readily, was used as a marker compound to examine mixture component effects using in vitro porcine skin models. PCP was administered in ethanol or in a 40% ethanol/60% water mixture or a 40% ethanol/60% water mixture containing either the rubefacient methyl nicotinate (MNA) or the surfactant sodium lauryl sulfate (SLS), or both MNA and SLS. Experiments were also conducted with {sup 14}C-labelled 3,3',4,4'-tetrachlorobiphenyl (TCB) and 3,3',4,4',5-pentachlorobiphenyl (PCB). Maximal PCP absorption was 14.12% of the applied dose from the mixture containing SLS, MNA, ethanol and water. However, when PCP was administered in ethanol only, absorption was only 1.12% of the applied dose. There were also qualitative differences among the absorption profiles for the different PCP mixtures. In contrast with the PCP results, absorption of TCB or PCB was negligible in perfused porcine skin, with only 0.14% of the applied TCB dose and 0.05% of the applied PCB dose being maximally absorbed. The low absorption levels for the PCB congeners precluded the identification of mixture component effects. These results suggest that dermal absorption estimates from a single chemical exposure may not reflect absorption seen after exposure as a chemical mixture and that absorption of both TCB and PCB are minimal in this model system. (orig.)

In vivo and in vitro dermal penetration of lipophilic and hydrophilic pesticides in mice

International Nuclear Information System (INIS)

Grissom, R.E. Jr.; Brownie, C.; Guthrie, F.E.

1987-01-01

Dermal absorption is a major portal of entry for a wide variety of potentially toxic substances. In vivo and in vitro investigations assessing penetration of topically applied xenobiotics using both human and other animals have been conducted. Current ethical considerations have drastically curtailed the testing of xenobiotics in human volunteers; consequently, dermal penetration in humans is usually estimated from in vivo tests in animals and in vitro tests using either human or animal skin. In order for in vitro penetration results to be meaningful, there needs to be close relationship with in vivo data. The objective of the present study was to investigate the relationship between in vivo and in vitro penetration of both hydrophilic and lipophilic 14 C-labelled compounds in mice

A case of congenital dermal sinus of the occipital region detected by CT at the onset of meningitis

International Nuclear Information System (INIS)

Fujiwara, Katsuhiko; Esumi, Noriko; Nishimura, Osamu

1985-01-01

A 4-year-old girl who was found to have congenital dermal sinus of the occipital region by CT at the second onset of meningitis is reported. CT at the first onset of meningitis (at the age of 3 years and 9 months) revealed only small, oval low density areas in the posterior fossa of the occipital region. CT at the second onset showed an abscess in the posterior fossa and dissociation in the posterior part of the cranium. Skin examination in the occipital region disclosed induration of the median area. Thus, congenital dermal sinus was suspected. Further CT disclosed that the patient subsequently developed hydrocephalus despite the intravenous and intrameningeal administration of antibiotics. Therefore, she underwent excision of a cyst and was pathologically diagnosed as having dermoid associated with abscess in the tip of the dermal sinus, which was followed by induration of the occipital skin. (Namekawa, K.)

Regulation of gene expression by tobacco product preparations in cultured human dermal fibroblasts

International Nuclear Information System (INIS)

Malpass, Gloria E.; Arimilli, Subhashini; Prasad, G.L.; Howlett, Allyn C.

2014-01-01

Skin fibroblasts comprise the first barrier of defense against wounds, and tobacco products directly contact the oral cavity. Cultured human dermal fibroblasts were exposed to smokeless tobacco extract (STE), total particulate matter (TPM) from tobacco smoke, or nicotine at concentrations comparable to those found in these extracts for 1 h or 5 h. Differences were identified in pathway-specific genes between treatments and vehicle using qRT-PCR. At 1 h, IL1α was suppressed significantly by TPM and less significantly by STE. Neither FOS nor JUN was suppressed at 1 h by tobacco products. IL8, TNFα, VCAM1, and NFκB1 were suppressed after 5 h with STE, whereas only TNFα and NFκB1 were suppressed by TPM. At 1 h with TPM, secreted levels of IL10 and TNFα were increased. Potentially confounding effects of nicotine were exemplified by genes such as ATF3 (5 h), which was increased by nicotine but suppressed by other components of STE. Within 2 h, TPM stimulated nitric oxide production, and both STE and TPM increased reactive oxygen species. The biological significance of these findings and utilization of the gene expression changes reported herein regarding effects of the tobacco product preparations on dermal fibroblasts will require additional research. - Highlights: • Tobacco product preparations (TPPs) alter gene expression in dermal fibroblasts. • Some immediate early genes critical to the inflammatory process are affected. • Different TPPs produce differential responses in certain pro-inflammatory genes

Regulation of gene expression by tobacco product preparations in cultured human dermal fibroblasts

Energy Technology Data Exchange (ETDEWEB)

Malpass, Gloria E., E-mail: gloria.malpass@gmail.com [Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Winston-Salem, NC 27157 (United States); Arimilli, Subhashini, E-mail: sarimill@wakehealth.edu [Department of Microbiology and Immunology, Wake Forest University Health Sciences, Winston-Salem, NC 27157 (United States); Prasad, G.L., E-mail: prasadg@rjrt.com [R and D Department, R.J. Reynolds Tobacco Company, Winston-Salem, NC 27102 (United States); Howlett, Allyn C., E-mail: ahowlett@wakehealth.edu [Department of Physiology and Pharmacology, Wake Forest University Health Sciences, Winston-Salem, NC 27157 (United States)

2014-09-01

Skin fibroblasts comprise the first barrier of defense against wounds, and tobacco products directly contact the oral cavity. Cultured human dermal fibroblasts were exposed to smokeless tobacco extract (STE), total particulate matter (TPM) from tobacco smoke, or nicotine at concentrations comparable to those found in these extracts for 1 h or 5 h. Differences were identified in pathway-specific genes between treatments and vehicle using qRT-PCR. At 1 h, IL1α was suppressed significantly by TPM and less significantly by STE. Neither FOS nor JUN was suppressed at 1 h by tobacco products. IL8, TNFα, VCAM1, and NFκB1 were suppressed after 5 h with STE, whereas only TNFα and NFκB1 were suppressed by TPM. At 1 h with TPM, secreted levels of IL10 and TNFα were increased. Potentially confounding effects of nicotine were exemplified by genes such as ATF3 (5 h), which was increased by nicotine but suppressed by other components of STE. Within 2 h, TPM stimulated nitric oxide production, and both STE and TPM increased reactive oxygen species. The biological significance of these findings and utilization of the gene expression changes reported herein regarding effects of the tobacco product preparations on dermal fibroblasts will require additional research. - Highlights: • Tobacco product preparations (TPPs) alter gene expression in dermal fibroblasts. • Some immediate early genes critical to the inflammatory process are affected. • Different TPPs produce differential responses in certain pro-inflammatory genes.

Inverted duplication including Endothelin 3 closely related to dermal hyperpigmentation in Silkie chickens

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Ming TIAN,Suyun FANG,Yanqiang WANG,Xiaorong GU,Chungang FENG,Rui HAO,Xiaoxiang HU,Ning LI

2014-06-01

Full Text Available The dermal hyperpigmentation phenotype in chickens is controlled by the dominant fibromelanosis allele. One of the ten unique characteristics of Silkie chickens is the fibromelanosis phenotype, which is pigmentation in the dermal layer of the skin and connective tissue. In this study, we found a mutation of fibromelanosis, a genomic rearrangement that included an inverted duplication of endothelin3 (EDN3, is responsible. We show that, as a stimulator of melanoblast proliferation, EDN3 expression was increased in silkie embryos and in both skin and muscle throughout adulthood. EDN3 expression led to an increase in expression of the downstream genes EDNRB2 and TYRP2, and was closely relate with the hyperpigmentation phenotype. We examined eight different Chinese chicken breeds showing hyperpigmentation and conclude that this structural genetic variant exists in all fibromelanosis chicken breeds.

Secondary cytotoxicity of (crosslinked) dermal sheep collagen during repeated exposure to human fibroblasts

NARCIS (Netherlands)

van Luyn, M.J.A.; van Wachem, P.B.; Olde damink, L.H.H.; Olde Damink, L.H.H.; Dijkstra, Pieter J.; Feijen, Jan; Nieuwenhuis, P.

1992-01-01

We investigated commercially available dermal sheep collagen either cross-linked with hexamethylenediisocyanate, or cross-linked with glutaraldehyde. In previous in vitro studies we could discriminate primary, i.e. extractable, and secondary cytotoxicity, due to cell-biomaterial interactions, i.e.

Exploratory breath analyses for assessing toxic dermal exposures of firefighters during suppression of structural burns.

Science.gov (United States)

Pleil, Joachim D; Stiegel, Matthew A; Fent, Kenneth W

2014-09-01

Firefighters wear fireproof clothing and self-contained breathing apparatus (SCBA) during rescue and fire suppression activities to protect against acute effects from heat and toxic chemicals. Fire services are also concerned about long-term health outcomes from chemical exposures over a working lifetime, in particular about low-level exposures that might serve as initiating events for adverse outcome pathways (AOP) leading to cancer. As part of a larger US National Institute for Occupational Safety and Health (NIOSH) study of dermal exposure protection from safety gear used by the City of Chicago firefighters, we collected pre- and post-fire fighting breath samples and analyzed for single-ring and polycyclic aromatic hydrocarbons as bioindicators of occupational exposure to gas-phase toxicants. Under the assumption that SCBA protects completely against inhalation exposures, any changes in the exhaled profile of combustion products were attributed to dermal exposures from gas and particle penetration through the protective clothing. Two separate rounds of firefighting activity were performed each with 15 firefighters per round. Exhaled breath samples were collected onto adsorbent tubes and analyzed with gas-chromatography-mass spectrometry (GC-MS) with a targeted approach using selective ion monitoring. We found that single ring aromatics and some PAHs were statistically elevated in post-firefighting samples of some individuals, suggesting that fire protective gear may allow for dermal exposures to airborne contaminants. However, in comparison to a previous occupational study of Air Force maintenance personnel where similar compounds were measured, these exposures are much lower suggesting that firefighters' gear is very effective. This study suggests that exhaled breath sampling and analysis for specific targeted compounds is a suitable method for assessing systemic dermal exposure in a simple and non-invasive manner.

Enriched Astaxanthin Extract from Haematococcus pluvialis Augments Growth Factor Secretions to Increase Cell Proliferation and Induces MMP1 Degradation to Enhance Collagen Production in Human Dermal Fibroblasts

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Hsin-Yu Chou

2016-06-01

Full Text Available Among many antioxidants that are used for the repairing of oxidative stress induced skin damages, we identified the enriched astaxanthin extract (EAE from Haematococcus pluvialis as a viable ingredient. EAE was extracted from the red microalgae through supercritical fluid carbon dioxide extraction. To compare the effectiveness, EAE wastreated on human dermal fibroblasts with other components, phorbol 12-myristate 13-acetate (PMA, and doxycycline. With sirius red staining and quantitative real-time polymerase chain reaction (qRT-PCR, we found that PMA decreased the collagen concentration and production while overall the addition of doxycycline and EAE increased the collagen concentration in a trial experiments. EAE increased collagen contents through inhibited MMP1 and MMP3 mRNA expression and induced TIMP1, the antagonists of MMPs protein, gene expression. As for when tested for various proteins through western blotting, it was seen that the addition of EAE increased the expression of certain proteins that promote cell proliferation. Testing those previous solutions using growth factor assay, it was noticeable that EAE had a positive impact on cell proliferation and vascular endothelial growth factor (VEGF than doxycycline, indicating that it was a better alternative treatment for collagen production. To sum up, the data confirmed the possible applications as medical cosmetology agentsand food supplements.

Microporous dermal-mimetic electrospun scaffolds pre-seeded with fibroblasts promote tissue regeneration in full-thickness skin wounds.

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Paul P Bonvallet

Full Text Available Electrospun scaffolds serve as promising substrates for tissue repair due to their nanofibrous architecture and amenability to tailoring of chemical composition. In this study, the regenerative potential of a microporous electrospun scaffold pre-seeded with dermal fibroblasts was evaluated. Previously we reported that a 70% collagen I and 30% poly(Ɛ-caprolactone electrospun scaffold (70:30 col/PCL containing 160 μm diameter pores had favorable mechanical properties, supported fibroblast infiltration and subsequent cell-mediated deposition of extracellular matrix (ECM, and promoted more rapid and effective in vivo skin regeneration when compared to scaffolds lacking micropores. In the current study we tested the hypothesis that the efficacy of the 70:30 col/PCL microporous scaffolds could be further enhanced by seeding scaffolds with dermal fibroblasts prior to implantation into skin wounds. To address this hypothesis, a Fischer 344 (F344 rat syngeneic model was employed. In vitro studies showed that dermal fibroblasts isolated from F344 rat skin were able to adhere and proliferate on 70:30 col/PCL microporous scaffolds, and the cells also filled the 160 μm pores with native ECM proteins such as collagen I and fibronectin. Additionally, scaffolds seeded with F344 fibroblasts exhibited a low rate of contraction (~14% over a 21 day time frame. To assess regenerative potential, scaffolds with or without seeded F344 dermal fibroblasts were implanted into full thickness, critical size defects created in F344 hosts. Specifically, we compared: microporous scaffolds containing fibroblasts seeded for 4 days; scaffolds containing fibroblasts seeded for only 1 day; acellular microporous scaffolds; and a sham wound (no scaffold. Scaffolds containing fibroblasts seeded for 4 days had the best response of all treatment groups with respect to accelerated wound healing, a more normal-appearing dermal matrix structure, and hair follicle regeneration

Nanocrystals of medium soluble actives--novel concept for improved dermal delivery and production strategy.

Science.gov (United States)

Zhai, Xuezhen; Lademann, Jürgen; Keck, Cornelia M; Müller, Rainer H

2014-08-15

After use in oral pharmaceutical products, nanocrystals are meanwhile applied to improve the dermal penetration of cosmetic actives (e.g. rutin, hesperidin) and of drugs. By now, nanocrystals are only dermally applied made from poorly soluble actives. The novel concept is to formulate nanocrystals also from medium soluble actives, and to apply a dermal formulation containing additionally nanocrystals. The nanocrystals should act as fast dissolving depot, increase saturation solubility and especially accumulate in the hair follicles, to further increase skin penetration. Caffeine was used as model compound with relevance to market products, and a particular process was developed for the production of caffeine nanocrystals to overcome the supersaturation related effect of crystal growth and fiber formation - typical with medium soluble compounds. It is based on low energy milling (pearl milling) in combination with low dielectric constant dispersion media (water-ethanol or ethanol-propylene glycol mixtures) and optimal stabilizers. Most successful was Carbopol(®) 981 (e.g. 20% caffeine in ethanol-propylene glycol 3:7 with 2% Carbopol, w/w). Nanocrystals with varied sizes can now be produced in a controlled process e.g. 660 nm (optimal for hair follicle accumulation) to 250 nm (optimal for fast dissolution). The short term test proved stability over 2 months of the present formulation being sufficient to perform in vivo testing of the novel concept. Copyright © 2014 Elsevier B.V. All rights reserved.

Default values for assessment of potential dermal exposure of the hands to industrial chemicals in the scope of regulatory risk assessments.

Science.gov (United States)

Marquart, Hans; Warren, Nicholas D; Laitinen, Juha; van Hemmen, Joop J

2006-07-01

Dermal exposure needs to be addressed in regulatory risk assessment of chemicals. The models used so far are based on very limited data. The EU project RISKOFDERM has gathered a large number of new measurements on dermal exposure to industrial chemicals in various work situations, together with information on possible determinants of exposure. These data and information, together with some non-RISKOFDERM data were used to derive default values for potential dermal exposure of the hands for so-called 'TGD exposure scenarios'. TGD exposure scenarios have similar values for some very important determinant(s) of dermal exposure, such as amount of substance used. They form narrower bands within the so-called 'RISKOFDERM scenarios', which cluster exposure situations according to the same purpose of use of the products. The RISKOFDERM scenarios in turn are narrower bands within the so-called Dermal Exposure Operation units (DEO units) that were defined in the RISKOFDERM project to cluster situations with similar exposure processes and exposure routes. Default values for both reasonable worst case situations and typical situations were derived, both for single datasets and, where possible, for combined datasets that fit the same TGD exposure scenario. The following reasonable worst case potential hand exposures were derived from combined datasets: (i) loading and filling of large containers (or mixers) with large amounts (many litres) of liquids: 11,500 mg per scenario (14 mg cm(-2) per scenario with surface of the hands assumed to be 820 cm(2)); (ii) careful mixing of small quantities (tens of grams in default values are considered useful for estimating exposure for similar substances in similar situations with low uncertainty. Several other default values based on single datasets can also be used, but lead to estimates with a higher uncertainty, due to their more limited basis. Sufficient analogy in all described parameters of the scenario, including duration, is needed

Determinants of Dermal Exposure Relevant for Exposure Modelling in Regulatory Risk Assessment

NARCIS (Netherlands)

Marquart, J.; Brouwer, D.H.; Gijsbers, J.H.J.; Links, I.H.M.; Warren, N.; Hemmen, J.J. van

2003-01-01

Risk assessment of chemicals requires assessment of the exposure levels of workers. In the absence of adequate specific measured data, models are often used to estimate exposure levels. For dermal exposure only a few models exist, which are not validated externally. In the scope of a large European

Phenotypic differences between oral and skin fibroblasts in wound contraction and growth factor expression.

Science.gov (United States)

Shannon, Diane B; McKeown, Scott T W; Lundy, Fionnuala T; Irwin, Chris R

2006-01-01

Wounds of the oral mucosa heal in an accelerated fashion with reduced scarring compared with cutaneous wounds. The differences in healing outcome between oral mucosa and skin could be because of phenotypic differences between the respective fibroblast populations. This study compared paired mucosal and dermal fibroblasts in terms of collagen gel contraction, alpha-smooth muscle actin expression (alpha-SMA), and production of the epithelial growth factors: keratinocyte growth factor (KGF) and hepatocyte growth factor/scatter factor (HGF). The effects of transforming growth factor -beta1 and -beta3 on each parameter were also determined. Gel contraction in floating collagen lattices was determined over a 7-day period. alpha-SMA expression by fibroblasts was determined by Western blotting. KGF and HGF expression were determined by an enzyme-linked immunosorbent assay. Oral fibroblasts induced accelerated collagen gel contraction, yet surprisingly expressed lower levels of alpha-SMA. Oral cells also produced significantly greater levels of both KGF and HGF than their dermal counterparts. Transforming growth factor-beta1 and -beta3, over the concentration range of 0.1-10 ng/mL, had similar effects on cell function, stimulating both gel contraction and alpha-SMA production, but inhibiting KGF and HGF production by both cell types. These data indicate phenotypic differences between oral and dermal fibroblasts that may well contribute to the differences in healing outcome between these two tissues.

Analyses of the correlation between dermal and blood carotenoids in female cattle by optical methods.

Science.gov (United States)

Klein, Julia; Darvin, Maxim E; Meinke, Martina C; Schweigert, Florian J; Müller, Kerstin E; Lademann, Jürgen

2013-06-01

Herd health programs for the maintenance of welfare and productivity in cattle need efficient tools for monitoring the health of individual animals. Recent reports demonstrate that the oxidative status is related to various stress conditions in dairy cows. Biomarkers, among other carotenoids, could serve as indicators of stress originating from the environment (e.g., heat stress or sun radiation) or from the animal itself (e.g., disease). To date, only invasive in vitro tests are available to assess the oxidative status in cattle. The present study compares the results of optical noninvasive in vivo measurements of dermal carotenoids in cattle udder skin using an LED-based miniaturized spectroscopic system (MSS) with those obtained by photometric analysis of beta carotene in whole blood samples using a portable device. Correlations between the concentrations of dermal and blood carotenoids were calculated under consideration of the nutritional status of the animals. Significant correlation (R = 0.86) was found for cattle with a moderate to obese body condition. Thus, the blood and skin concentrations of the marker substance beta carotene are comparable under stable stress conditions of the cattle. This demonstrates that the MSS is suitable for noninvasive assessment of dermal carotenoid concentrations in cattle.

Assessment of occupational exposure to malathion and bifenthrin in mosquito control sprayers through dermal contact.

Science.gov (United States)

Kongtip, Pornpimol; Sasrisuk, Somnuek; Preklang, Smart; Yoosook, Witaya; Sujirarat, Dusit

2013-12-01

To assess occupational exposure of malathion and bifenthrin concentrations by dermal contact and urinary 3-(2-chloro-3, 3, 3-trifluoro-1-propenyl)-2, 2-dimethyl-cyclopropanecarboxylic (TFP) acid, health symptoms developed and the relationship between bifenthrin concentrations and TFP acid in urine of the mosquito control sprayers. The aerosols of these two pesticides were collected using 100 cm2 cotton patches attached on the skin of upper legs of 54 volunteer of mosquito control sprayers. Their urine samples were also collected before and after application. These subjects exposed to average malathion and bifenthrin concentrations of 0.18 and 0.32 microg/cm2, respectively After application, the average concentration of urinary TFP acid in the sprayers was 39.22 +/- 0.77 mg/g creatinine ranging from 0.58 to 261.19 mg/g creatinine. A significant difference was found between urinary TFP acid levels before and after application (p bifenthrin concentrations through dermal contact and urinary TFP acid levels were not significantly correlated (p > 0.05). The mosquito control sprayers had dermal contact with smoke of malathion and bifenthrin and some sprayers developed health symptoms after exposure. They should use protective clothing made ofplastic, nylon or polyester to protect sprayers from skin contact.

Dermal arteritis of the nasal philtrum in a Giant Schnauzer and three Saint Bernard dogs.

Science.gov (United States)

Torres, Sheila M F; Brien, Timothy O; Scott, Danny W

2002-10-01

Arteritis of the nasal philtrum is described in four dogs. Two of the Saint Bernards were related. The lesions were solitary, well-circumscribed, linear ulcers that were neither pruritic nor painful. The age of the dogs at the time the owners first noticed the lesion ranged from 3 to 6 years. The ulcers had been present for 0.5-5 years before diagnosis was pursued. Three of the dogs experienced repeated, mild episodes of arterial bleeding from the ulcers. Two dogs also experienced a severe episode of bleeding that required surgical intervention. Histopathological findings included a V-shaped ulcer, neutrophilic dermal inflammation subjacent to the ulcer and lymphoplasmacytic dermatitis bordering the ulcer. The most remarkable pathological findings were present in the deep dermal arteries and arterioles subjacent to the ulcer. The changes were characterized by subendothelial spindle cell proliferation with marked extracellular matrix deposition that stained blue with Alcian Blue (mucin) and Masson's trichrome (collagen) and resulted in intimal thickening, and stenosis of dermal arteries and arterioles. Immunohistochemical studies suggested that the proliferating spindle cells were of either myofibroblast or smooth muscle origin (actin and vimentin positive). Anti-inflammatory therapy (glucocorticoids; tetracycline and niacinamide; fish oil) may be beneficial for long-term control of this condition, however, long-term maintenance treatment appears to be necessary.

A complex genomic rearrangement involving the endothelin 3 locus causes dermal hyperpigmentation in the chicken.

Directory of Open Access Journals (Sweden)

Ben Dorshorst

2011-12-01

Full Text Available Dermal hyperpigmentation or Fibromelanosis (FM is one of the few examples of skin pigmentation phenotypes in the chicken, where most other pigmentation variants influence feather color and patterning. The Silkie chicken is the most widespread and well-studied breed displaying this phenotype. The presence of the dominant FM allele results in extensive pigmentation of the dermal layer of skin and the majority of internal connective tissue. Here we identify the causal mutation of FM as an inverted duplication and junction of two genomic regions separated by more than 400 kb in wild-type individuals. One of these duplicated regions contains endothelin 3 (EDN3, a gene with a known role in promoting melanoblast proliferation. We show that EDN3 expression is increased in the developing Silkie embryo during the time in which melanoblasts are migrating, and elevated levels of expression are maintained in the adult skin tissue. We have examined four different chicken breeds from both Asia and Europe displaying dermal hyperpigmentation and conclude that the same structural variant underlies this phenotype in all chicken breeds. This complex genomic rearrangement causing a specific monogenic trait in the chicken illustrates how novel mutations with major phenotypic effects have been reused during breed formation in domestic animals.

Analyses of the correlation between dermal and blood carotenoids in female cattle by optical methods

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Klein, Julia; Darvin, Maxim E.; Meinke, Martina C.; Schweigert, Florian J.; Müller, Kerstin E.; Lademann, Jürgen

2013-06-01

Herd health programs for the maintenance of welfare and productivity in cattle need efficient tools for monitoring the health of individual animals. Recent reports demonstrate that the oxidative status is related to various stress conditions in dairy cows. Biomarkers, among other carotenoids, could serve as indicators of stress originating from the environment (e.g., heat stress or sun radiation) or from the animal itself (e.g., disease). To date, only invasive in vitro tests are available to assess the oxidative status in cattle. The present study compares the results of optical noninvasive in vivo measurements of dermal carotenoids in cattle udder skin using an LED-based miniaturized spectroscopic system (MSS) with those obtained by photometric analysis of beta carotene in whole blood samples using a portable device. Correlations between the concentrations of dermal and blood carotenoids were calculated under consideration of the nutritional status of the animals. Significant correlation (R=0.86) was found for cattle with a moderate to obese body condition. Thus, the blood and skin concentrations of the marker substance beta carotene are comparable under stable stress conditions of the cattle. This demonstrates that the MSS is suitable for noninvasive assessment of dermal carotenoid concentrations in cattle.

Comparison of native porcine skin and a dermal substitute using tensiometry and digital image speckle correlation.

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Fritz, Jason R; Phillips, Brett T; Conkling, Nicole; Fourman, Mitchell; Melendez, Mark M; Bhatnagar, Divya; Simon, Marcia; Rafailovich, Miriam; Dagum, Alexander B

2012-10-01

Dermal substitutes are currently used in plastic surgery to cover various soft tissue defects caused by trauma, burns, or ablative cancer surgery. Little information is available on the biomechanical properties of these dermal substitutes after adequate incorporation as compared to normal skin. Determining parameters such as tensile strength in these skin substitutes will help us further understand their wound healing properties and potential in developing artificial tissue constructs. We hypothesize that a dermal substitute has a lower stress-strain curve and altered stress-induced deformation quantified with tensiometry and digital image speckle correlation (DISC) analysis. Two separate 5×10-cm full-thickness wounds were created on the dorsum of 3 female swine. Fibrin glue was applied before either a full-thickness skin graft (FTSG) or application of artificial dermal matrix. On day 42, cultured autologous keratinocytes were applied as a cell sheet to the wound covered with Integra. On day 56, the wounds were fully excised and fresh tissue specimens, including normal skin, were stored in a physiological solution and prepared for analysis. Rectangular samples were excised from the center of each specimen measuring 4×4×30 mm. Using a tensiometer and DISC analysis, we evaluated the tensile strength of 3 different groups of skin, namely, normal, FTSG, and Integra. There is a significant difference between the Integra specimen when compared to normal skin and FTSG. We found a minimal difference in the stress-strain curves of the latter two. Integra alone shows plastic deformation with continued stretching before ultimate midline fracture. There is significant change between the Young's moduli of the normal skin and the Integra, whereas there is little difference between the FTSG and the normal skin; DISC confirms this analysis. The normal skin and FTSG show a convergence of vectors to a linear plane, whereas Integra shows very little organization. Using 2 different

Scented traces--Dermal exposure of synthetic musk fragrances in personal care products and environmental input assessment.

Science.gov (United States)

Homem, Vera; Silva, Eduardo; Alves, Arminda; Santos, Lúcia

2015-11-01

Synthetic musks are organic compounds used as fragrance and fixative additives in several personal care products. Until now, little is known about their occurrence and distribution in these household commodities. However, this information is essential to perform a human dermal exposure assessment. Therefore, this study gives an overview on the levels of 12 synthetic musks in 140 personal care products from 7 different categories (body and hair wash, toilet soaps, shaving products, dentifrice products, deodorants/antiperspirants, moisturizers and perfumes). They were analysed by QuEChERS extraction followed by gas chromatography-mass spectrometry. Detection limits were found between 0.01ngg(-1) (galaxolide) and 5.00ngg(-1) (musk xylene). Higher average concentrations of total synthetic musks were detected in perfumes (5245.05μgg(-1)) and shampoos (487.67μgg(-1)) for adults. Galaxolide, exaltolide and cashmeran were the most detected compounds. Combining these results with the daily usage amounts, an average daily dermal exposure of 75.69μgkgbw(-1)day(-1) for adults and 15.54μgkgbw(-1)day(-1) for babies/children was achieved. The main contributors for adult and babies/children dermal exposure were perfumes and lotions, respectively. About 40% of the adult daily dermal exposure is related to exaltolide, 30% galaxolide, and 15% tonalide, while for babies/children 96% occurs due to exaltolide. An estimate of the amount of musks discharged "down-the-drain" into the wastewater treatment systems through the use of toiletries was also performed. An average emission per capita of 6.7mgday(-1) was determined and galaxolide and exaltolide were the predominant musks in the effluents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Further delineation of the odonto-onycho-dermal dysplasia syndrome.

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Mégarbané, Hala; Haddad, May; Delague, Valérie; Renoux, Julien; Boehm, Nelly; Mégarbané, André

2004-08-30

We report on three boys, two brothers and their maternal cousin, presenting with dry hair, pilar keratosis, severe hypodontia, smooth tongue, onychodysplasia, and keratoderma and hyperhidrosis of palms and soles. Histology of the skin showed orthokeratotic, hyperkeratosis, hypergranulosis, and mild acanthosis in the epidermis. Scanning electron microscopic examination of the hair showed longitudinal depressions in some hair. These features are close to a rare entity: the odonto-onycho-dermal dysplasia but with some differing features. Copyright 2004 Wiley-Liss, Inc.

[Autogenous platelet-rich plasma gel with acellular xenogeneic dermal matrix for treatment of deep II degree burns].

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Hao, Tianzhi; Zhu, Jingmin; Hu, Wenbo; Zhang, Hua; Gao, Zhenhui; Wen, Xuehui; Zhou, Zhi; Lu, Gang; Liu, Jingjie; Li, Wen

2010-06-01

To investigate the effectiveness of autogenous platelet-rich plasma (PRP) gel with acellular xenogeneic dermal matrix in the treatment of deep II degree burns. From January 2007 to December 2009, 30 cases of deep II degree burns were treated. There were 19 males and 11 females with an average age of 42.5 years (range, 32-57 years). The burn area was 10% to 48% of total body surface area. The time from burn to hospitalization was 30 minutes to 8 hours. All patients were treated with tangential excision surgery, one side of the wounds were covered with autogenous PRP gel and acellular xenogeneic dermal matrix (PRP group), the other side of the wounds were covered with acellular xenogeneic dermal matrix only (control group). The healing rate, healing time, infection condition, and scar formation were observed. At 7 days after operation, the infection rate in PRP group (6.7%, 2/30) was significantly lower than that in control group (16.7%, 5/30, P deep II degree burns as well as alleviate the scar proliferation.

Formulation of diclofenac for dermal delivery.

Science.gov (United States)

Goh, Choon Fu; Lane, Majella E

2014-10-01

Diclofenac (DF) was first synthesized in the 1960's and is currently available as ophthalmic, oral, parenteral, rectal and skin preparations. This review focuses on the administration of DF to the skin. As a member of the non-steroidal anti-inflammatory (NSAID) group of drugs the primary indications of DF are for the management of inflammation and pain but it is also used to treat actinic keratosis. The specific aims of this paper are to: (i) provide an overview of the pharmacokinetics and metabolism of DF following oral and topical administration; (ii) examine critically the various formulation approaches which have been investigated to enhance dermal delivery of DF; and (iii) identify new formulation strategies for enhanced DF skin penetration. Copyright © 2014 Elsevier B.V. All rights reserved.

Augmentation of Distal Biceps Repair With an Acellular Dermal Graft Restores Native Biomechanical Properties in a Tendon-Deficient Model.

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Conroy, Christine; Sethi, Paul; Macken, Craig; Wei, David; Kowalsky, Marc; Mirzayan, Raffy; Pauzenberger, Leo; Dyrna, Felix; Obopilwe, Elifho; Mazzocca, Augustus D

2017-07-01

The majority of distal biceps tendon injuries can be repaired in a single procedure. In contrast, complete chronic tears with severe tendon substance deficiency and retraction often require tendon graft augmentation. In cases with extensive partial tears of the distal biceps, a human dermal allograft may be used as an alternative to restore tendon thickness and biomechanical integrity. Dermal graft augmentation will improve load to failure compared with nonaugmented repair in a tendon-deficient model. Controlled laboratory study. Thirty-six matched specimens were organized into 1 of 4 groups: native tendon, native tendon with dermal graft augmentation, tendon with an attritional defect, and tendon with an attritional defect repaired with a graft. To mimic a chronic attritional biceps lesion, a defect was created by a complete tear, leaving 30% of the tendon's width intact. The repair technique in all groups consisted of cortical button and interference screw fixation. All specimens underwent cyclical loading for 3000 cycles and were then tested to failure; gap formation and peak load at failure were documented. The mean (±SD) load to failure (320.9 ± 49.1 N vs 348.8 ± 77.6 N, respectively; P = .38) and gap formation (displacement) (1.8 ± 1.4 mm vs 1.6 ± 1.1 mm, respectively; P = .38) did not differ between the native tendon groups with and without graft augmentation. In the tendon-deficient model, the mean load to failure was significantly improved with graft augmentation compared with no graft augmentation (282.1 ± 83.8 N vs 199.7 ± 45.5 N, respectively; P = .04), while the mean gap formation was significantly reduced (1.2 ± 1.0 mm vs 2.7 ± 1.4 mm, respectively; P = .04). The mean load to failure of the deficient tendon with graft augmentation (282.1 N) compared with the native tendon (348.8 N) was not significantly different ( P = .12). This indicates that the native tendon did not perform differently from the grafted deficient tendon. In a tendon

Linking a dermal permeation and an inhalation model to a simple pharmacokinetic model to study airborne exposure to di(n-butyl) phthalate

DEFF Research Database (Denmark)

Lorber, Matthew; Weschler, Charles J.; Morrison, Glenn

2017-01-01

Six males clad only in shorts were exposed to high levels of airborne di(n-butyl) phthalate (DnBP) and diethyl phthalate (DEP) in chamber experiments conducted in 2014. In two 6 h sessions, the subjects were exposed only dermally while breathing clean air from a hood, and both dermally and via...

Predicting dermal absorption of gas-phase chemicals: transient model development, evaluation, and application

DEFF Research Database (Denmark)

Gong, M.; Zhang, Y.; Weschler, Charles J.

2014-01-01

A transient model is developed to predict dermal absorption of gas-phase chemicals via direct air-to-skin-to-blood transport under non-steady-state conditions. It differs from published models in that it considers convective mass-transfer resistance in the boundary layer of air adjacent to the skin....... Results calculated with this transient model are in good agreement with the limited experimental results that are available for comparison. The sensitivity of the modeled estimates to key parameters is examined. The model is then used to estimate air-to-skin-to-blood absorption of six phthalate esters...... and less absorbed into blood than would a steady-state model. In the 7-day scenario, results calculated by the transient and steady-state models converge over a time period that varies between 3 and 4days for all but the largest phthalate (DEHP). Dermal intake is comparable to or larger than inhalation...

Effect of Arctium lappa (burdock) extract on canine dermal fibroblasts.

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Pomari, Elena; Stefanon, Bruno; Colitti, Monica

2013-12-15

Although the biological activities of Arctium lappa (burdock) have been already investigated in human and other species, data evaluating the molecular mechanisms have not been reported in the dog. In this study we analyzed for the first time the effect of a root extract of burdock on molecular responses in canine dermal fibroblasts with H2O2 stimulation (H group), with burdock treatment (B group) and with H2O2 stimulation and burdock treatment (BH group), using RNAseq technology. Differentially expressed genes (P<0.05) of H, B and BH groups in comparison to the untreated sample (negative control, C group) were identified with MeV software and were functional annotated and monitored for signaling pathways and candidate biomarkers using the Ingenuity Pathways Analysis (IPA). The expression profile of canine dermal fibroblasts treated with burdock extract with or without H2O2 stimulation, showed an up-regulation of mitochondrial superoxide dismutase (SOD2), disheveled 3 (DVL3) and chondroitin sulfate N-acetylgalactosaminyltransferase 2 (CSGALNACT2). The data suggested that burdock has implications in cell adhesion and gene expression with the modulation of Wnt/β catenin signaling and Chondroitin Sulphate Biosynthesis that are particularly important for the wound healing process. © 2013 Elsevier B.V. All rights reserved.

Dermal and inhalation acute toxic class methods: test procedures and biometric evaluations for the Globally Harmonized Classification System.

Science.gov (United States)

Holzhütter, H G; Genschow, E; Diener, W; Schlede, E

2003-05-01

The acute toxic class (ATC) methods were developed for determining LD(50)/LC(50) estimates of chemical substances with significantly fewer animals than needed when applying conventional LD(50)/LC(50) tests. The ATC methods are sequential stepwise procedures with fixed starting doses/concentrations and a maximum of six animals used per dose/concentration. The numbers of dead/moribund animals determine whether further testing is necessary or whether the test is terminated. In recent years we have developed classification procedures for the oral, dermal and inhalation routes of administration by using biometric methods. The biometric approach assumes a probit model for the mortality probability of a single animal and assigns the chemical to that toxicity class for which the best concordance is achieved between the statistically expected and the observed numbers of dead/moribund animals at the various steps of the test procedure. In previous publications we have demonstrated the validity of the biometric ATC methods on the basis of data obtained for the oral ATC method in two-animal ring studies with 15 participants from six countries. Although the test procedures and biometric evaluations for the dermal and inhalation ATC methods have already been published, there was a need for an adaptation of the classification schemes to the starting doses/concentrations of the Globally Harmonized Classification System (GHS) recently adopted by the Organization for Economic Co-operation and Development (OECD). Here we present the biometric evaluation of the dermal and inhalation ATC methods for the starting doses/concentrations of the GHS and of some other international classification systems still in use. We have developed new test procedures and decision rules for the dermal and inhalation ATC methods, which require significantly fewer animals to provide predictions of toxicity classes, that are equally good or even better than those achieved by using the conventional LD(50)/LC

Unraveling the Relative Importance of Oral and Dermal Contaminant Exposure in Reptiles: Insights from Studies Using the Western Fence Lizard (Sceloporus occidentalis)

Science.gov (United States)

Weir, Scott M.; Talent, Larry G.; Anderson, Todd A.; Salice, Christopher J.

2014-01-01

Despite widespread recognition of significant data deficiencies, reptiles remain a relatively understudied taxon in ecotoxicology. To conduct ecological risk assessments on reptiles frequently requires using surrogate taxa such as birds, but recent research suggests that reptiles have significantly different exposure profiles and toxicant sensitivity. We exposed western fence lizards, Sceloporus occidentalis, to the same quantities of three model chemicals via oral (gavage) and dermal (ventral skin application) exposure for either 24 or 48 hours. Three phthalate esters (di-methyl phthalate [DMP], di-iso-butyl phthalate [DIBP], and di-n-octyl phthalate [DNOP]) were chosen as model chemicals because they represent a gradient of lipophilicity but are otherwise structurally similar. Overall, the more lipophilic phthalates (DIBP and DNOP) were found to have higher concentrations in tissues than the less lipophilic DMP. Significant differences in tissue concentrations between DIBP and DNOP were tissue-dependent, suggesting that delivery to a site of action following exposure is not only a simple function of lipophilicity. In dermal treatments, DMP usually had fewer detections (except in ventral skin samples), suggesting that lipophilicity (log Kow>2) is a requirement for uptake across the skin. In general, tissue residues were greater in oral treatments than dermal treatments (significant in adipose and liver tissue), but differences were driven strongly by differences in DMP which did not appear to be absorbed well across skin. When differences in tissue residue concentrations between oral and dermal exposure did occur, the difference was not drastic. Taken together these results suggest that dermal exposure should be considered in risk assessments for reptilian receptors. Dermal exposure may be an especially important route for reptiles as their ectothermic physiology translates to lower energetic demands and dietary exposure compared to birds and mammals. PMID

Unraveling the relative importance of oral and dermal contaminant exposure in reptiles: insights from studies using the western fence lizard (Sceloporus occidentalis).

Science.gov (United States)

Weir, Scott M; Talent, Larry G; Anderson, Todd A; Salice, Christopher J

2014-01-01

Despite widespread recognition of significant data deficiencies, reptiles remain a relatively understudied taxon in ecotoxicology. To conduct ecological risk assessments on reptiles frequently requires using surrogate taxa such as birds, but recent research suggests that reptiles have significantly different exposure profiles and toxicant sensitivity. We exposed western fence lizards, Sceloporus occidentalis, to the same quantities of three model chemicals via oral (gavage) and dermal (ventral skin application) exposure for either 24 or 48 hours. Three phthalate esters (di-methyl phthalate [DMP], di-iso-butyl phthalate [DIBP], and di-n-octyl phthalate [DNOP]) were chosen as model chemicals because they represent a gradient of lipophilicity but are otherwise structurally similar. Overall, the more lipophilic phthalates (DIBP and DNOP) were found to have higher concentrations in tissues than the less lipophilic DMP. Significant differences in tissue concentrations between DIBP and DNOP were tissue-dependent, suggesting that delivery to a site of action following exposure is not only a simple function of lipophilicity. In dermal treatments, DMP usually had fewer detections (except in ventral skin samples), suggesting that lipophilicity (log Kow>2) is a requirement for uptake across the skin. In general, tissue residues were greater in oral treatments than dermal treatments (significant in adipose and liver tissue), but differences were driven strongly by differences in DMP which did not appear to be absorbed well across skin. When differences in tissue residue concentrations between oral and dermal exposure did occur, the difference was not drastic. Taken together these results suggest that dermal exposure should be considered in risk assessments for reptilian receptors. Dermal exposure may be an especially important route for reptiles as their ectothermic physiology translates to lower energetic demands and dietary exposure compared to birds and mammals.

Attenuation fluctuations and local dermal reflectivity are indicators of immune cell infiltrate and epidermal hyperplasia in skin inflammation

Science.gov (United States)

Phillips, Kevin G.; Wang, Yun; Choudhury, Niloy; Levitz, David; Swanzey, Emily; Lagowski, James; Kulesz-Martin, Molly; Jacques, Steven

2012-02-01

Psoriasis is a common inflammatory skin disease resulting from genetic and environmental alterations of cutaneous immune responses responsible for skin homeostasis. While numerous therapeutic targets involved in the immunopathogenesis of psoriasis have been identified, the in vivo dynamics of psoriasis remains under investigated. To elucidate the spatial-temporal morphological evolution of psoriasis we undertook in vivo time course focus-tracked optical coherence tomography (OCT) imaging to non-invasively document dermal alterations due to immune cell infiltration and epidermal hyperplasia in an Imiquimod (IMQ) induced model of psoriasis-like inflammation in DBA2/C57Bl6 hybrid mice. Quantitative appraisal of dermal architectural changes was achieved through a three parameter fit of OCT axial scans in the dermis of the form A(z) = ρ exp(-mu;z +ɛ(z)). Ensemble averaging of the fit parameters over 2000 axial scans per mouse in each treatment arm revealed that the local dermal reflectivity ρ, decreased significantly in response to 6 day IMQ treatment (p = 0.0001), as did the standard deviation of the attenuation fluctuation std(ɛ(z)), (p = 0.04), in comparison to cream controls and day 1 treatments. No significant changes were observed in the average dermal attenuation rate, μ. Our results suggest these label-free OCT-based metrics can be deployed to investigate new therapeutic targets in animal models as well as aid in clinical staging of psoriasis in conjunction with the psoriasis area and severity index.

Repair of Postoperative Abdominal Hernia in a Child with Congenital Omphalocele Using Porcine Dermal Matrix

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V. Lambropoulos

2016-01-01

Full Text Available Introduction. Incisional hernias are a common complication appearing after abdominal wall defects reconstruction, with omphalocele and gastroschisis being the most common etiologies in children. Abdominal closure of these defects represents a real challenge for pediatric surgeons with many surgical techniques and various prosthetic materials being used for this purpose. Case Report. We present a case of repair of a postoperative ventral hernia occurring after congenital omphalocele reconstruction in a three-and-a-half-year-old child using an acellular, sterile, porcine dermal mesh. Conclusion. Non-cross-linked acellular porcine dermal matrix is an appropriate mesh used for the reconstruction of abdominal wall defects and their postoperative complications like large ventral hernias with success and preventing their recurrence.

The margin of internal exposure (MOIE) concept for dermal risk assessment based on oral toxicity data - A case study with caffeine.

Science.gov (United States)

Bessems, Jos G M; Paini, Alicia; Gajewska, Monika; Worth, Andrew

2017-12-01

Route-to-route extrapolation is a common part of human risk assessment. Data from oral animal toxicity studies are commonly used to assess the safety of various but specific human dermal exposure scenarios. Using theoretical examples of various user scenarios, it was concluded that delineation of a generally applicable human dermal limit value is not a practicable approach, due to the wide variety of possible human exposure scenarios, including its consequences for internal exposure. This paper uses physiologically based kinetic (PBK) modelling approaches to predict animal as well as human internal exposure dose metrics and for the first time, introduces the concept of Margin of Internal Exposure (MOIE) based on these internal dose metrics. Caffeine was chosen to illustrate this approach. It is a substance that is often found in cosmetics and for which oral repeated dose toxicity data were available. A rat PBK model was constructed in order to convert the oral NOAEL to rat internal exposure dose metrics, i.e. the area under the curve (AUC) and the maximum concentration (C max ), both in plasma. A human oral PBK model was constructed and calibrated using human volunteer data and adapted to accommodate dermal absorption following human dermal exposure. Use of the MOIE approach based on internal dose metrics predictions provides excellent opportunities to investigate the consequences of variations in human dermal exposure scenarios. It can accommodate within-day variation in plasma concentrations and is scientifically more robust than assuming just an exposure in mg/kg bw/day. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Efficiency of protective dermal equipment against silver nanoparticles with water aerosol

International Nuclear Information System (INIS)

Park, Junsu; Kwak, Byoung Kyu; Kim, Younghun; Yi, Jongheop

2011-01-01

Protective dermal equipment (PDE) should be provided for protecting against the penetration of nanomaterials into the skin in the workplace. It is important that workers utilize appropriate PDE with characteristics to accomplish this. During the liquid-phase process, nanomaterials are released with water aerosol, which can easily affect the health of workers. The efficiency of PDE in protecting workers against silver nanoparticles (AgNPs) aerosolized with water aerosol was evaluated. The rate of penetration of AgNPs with water aerosol through cleanroom wear was faster than that for a lab coat. This can be attributed to differences in the filling rate of water, as the result of differences in capillary force. Therefore, humidity appears to be a major factor in the rate of penetration of nanomaterials in the presence of water aerosol. Although no penetration was observed when disposable protective gloves were observed, the presence of AgNPs on the surface of gloves was clearly found. Based on these findings, recommendations for the safe use of PDE can now be made.

Oral mucosa: an alternative epidermic cell source to develop autologous dermal-epidermal substitutes from diabetic subjects

Directory of Open Access Journals (Sweden)

Daniela GUZMÁN-URIBE

Full Text Available Abstract Oral mucosa has been highlighted as a suitable source of epidermal cells due to its intrinsic characteristics such as its higher proliferation rate and its obtainability. Diabetic ulcers have a worldwide prevalence that is variable (1%-11%, meanwhile treatment of this has been proven ineffective. Tissue-engineered skin plays an important role in wound care focusing on strategies such autologous dermal-epidermal substitutes. Objective The aim of this study was to obtain autologous dermal-epidermal skin substitutes from oral mucosa from diabetic subjects as a first step towards a possible clinical application for cases of diabetic foot. Material and Methods Oral mucosa was obtained from diabetic and healthy subjects (n=20 per group. Epidermal cells were isolated and cultured using autologous fibrin to develop dermal-epidermal in vitro substitutes by the air-liquid technique with autologous human serum as a supplement media. Substitutes were immunocharacterized with collagen IV and cytokeratin 5-14 as specific markers. A Student´s t- test was performed to assess the differences between both groups. Results It was possible to isolate epidermal cells from the oral mucosa of diabetic and healthy subjects and develop autologous dermal-epidermal skin substitutes using autologous serum as a supplement. Differences in the expression of specific markers were observed and the cytokeratin 5-14 expression was lower in the diabetic substitutes, and the collagen IV expression was higher in the diabetic substitutes when compared with the healthy group, showing a significant difference. Conclusion Cells from oral mucosa could be an alternative and less invasive source for skin substitutes and wound healing. A difference in collagen production of diabetic cells suggests diabetic substitutes could improve diabetic wound healing. More research is needed to determine the crosstalk between components of these skin substitutes and damaged tissues.

Dermal uptake of phthalates from clothing: Comparison of model to human participant results

DEFF Research Database (Denmark)

Morrison, G. C.; Weschler, Charles J.; Beko, G.

2017-01-01

In this research, we extend a model of transdermal uptake of phthalates to include a layer of clothing. When compared with experimental results, this model better estimates dermal uptake of diethylphthalate and di-n-butylphthalate (DnBP) than a previous model. The model predictions are consistent...

Approach to quantify human dermal skin aging using multiphoton laser scanning microscopy

Science.gov (United States)

Puschmann, Stefan; Rahn, Christian-Dennis; Wenck, Horst; Gallinat, Stefan; Fischer, Frank

2012-03-01

Extracellular skin structures in human skin are impaired during intrinsic and extrinsic aging. Assessment of these dermal changes is conducted by subjective clinical evaluation and histological and molecular analysis. We aimed to develop a new parameter for the noninvasive quantitative determination of dermal skin alterations utilizing the high-resolution three-dimensional multiphoton laser scanning microscopy (MPLSM) technique. To quantify structural differences between chronically sun-exposed and sun-protected human skin, the respective collagen-specific second harmonic generation and the elastin-specific autofluorescence signals were recorded in young and elderly volunteers using the MPLSM technique. After image processing, the elastin-to-collagen ratio (ELCOR) was calculated. Results show that the ELCOR parameter of volar forearm skin significantly increases with age. For elderly volunteers, the ELCOR value calculated for the chronically sun-exposed temple area is significantly augmented compared to the sun-protected upper arm area. Based on the MPLSM technology, we introduce the ELCOR parameter as a new means to quantify accurately age-associated alterations in the extracellular matrix.

Osteopathia striata: a characteristic X-ray finding in focal dermal hypoplasia (Goltz-Gorlin syndrome)

Energy Technology Data Exchange (ETDEWEB)

Barthels, W.; Boepple, D.; Petzel, H.

1982-12-01

Two cases of the very rare Goltz-Gorlin syndrome are presented. The relationship of osteopathia striata and focal dermal hypoplasia is discussed, and it is concluded that the osteopathia striata represents the characteristic picture of this ectopic mesodermal abnormality.

SECONDARY CYTOTOXICITY OF CROSS-LINKED DERMAL SHEEP COLLAGENS DURING REPEATED EXPOSURE TO HUMAN FIBROBLASTS

NARCIS (Netherlands)

VANLUYN, MJA; VANWACHEM, PB; DAMINK, LHHO; DIJKSTRA, PJ; FEIJEN, J; NIEUWENHUIS, P

1992-01-01

We investigated commercially available dermal sheep collagen either cross-linked with hexamethylenedlisocyanate, or cross-linked with glutaraldehyde. In previous in vitro studies we could discriminate primary, i.e. extractable, and secondary cytotoxicity, due to cell-biomaterial interactions, i.e.

Coexistence of dermal sinus tract, dermoid cyst, and encephalocele in a patient presenting with nasal cellulitis.

Science.gov (United States)

Karandikar, Mahesh; Yellon, Robert F; Murdoch, Geoffrey; Greene, Stephanie

2013-01-01

Dermoid cysts, encephaloceles, and dermal sinus tracts represent abnormalities that develop during the process of embryogenesis. The elucidation of the precise timing of formation for these malformations has remained elusive at the molecular level of study. Yet, clinical experience has demonstrated that these malformations do not all occur in the same patient, suggesting a shared pathway that goes awry at distinct points for different patients, resulting in 1 of the 3 malformations. Herein the authors describe a case in which all 3 malformations were present in a single patient. This is the first description in the English literature of a sincipital encephalocele occurring with a dermoid cyst and a dermal sinus tract.

Nestin is expressed in HMB-45 negative melanoma cells in dermal parts of nodular melanoma.

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Kanoh, Maho; Amoh, Yasuyuki; Tanabe, Kenichi; Maejima, Hideki; Takasu, Hiroshi; Katsuoka, Kensei

2010-06-01

Nestin, a marker of neural stem cells, is expressed in the stem cells of the mouse hair follicle. The nestin-expressing hair follicle stem cells can differentiate into neurons, glia, keratocytes, smooth muscle cells and melanocytes in vitro. These pluripotent nestin-expressing stem cells are keratin 15 (K15)-negative, suggesting that they are in a relatively undifferentiated state. Recent studies suggest that the epithelial stem cells are important in tumorigenesis, and nestin expression is thought to be important in tumorigenesis. In the present study, we examined the expression of the hair follicle and neural stem cell marker nestin, as well as S-100 and HMB-45, in melanoma. Nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in all five cases of amelanotic nodular melanomas. Moreover, nestin immunoreactivity was observed in the dermal parts in seven of 10 cases of melanotic nodular melanomas. Especially, nestin immunoreactivity was observed in the HMB-45-negative melanoma cells in the dermal parts of all 10 cases of HMB-45-negative amelanotic and melanotic nodular melanomas. On the other hand, nestin expression was negative in 10 of 12 cases of superficial spreading melanoma. These results suggest that nestin is an important marker of HMB-45-negative melanoma cells in the dermal parts of patients with nodular melanoma.

Design of a Novel Two-Component Hybrid Dermal Scaffold for the Treatment of Pressure Sores.

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Sharma, Vaibhav; Kohli, Nupur; Moulding, Dale; Afolabi, Halimat; Hook, Lilian; Mason, Chris; García-Gareta, Elena

2017-11-01

The aim of this study is to design a novel two-component hybrid scaffold using the fibrin/alginate porous hydrogel Smart Matrix combined to a backing layer of plasma polymerized polydimethylsiloxane (Sil) membrane to make the fibrin-based dermal scaffold more robust for the treatment of the clinically challenging pressure sores. A design criteria are established, according to which the Sil membranes are punched to avoid collection of fluid underneath. Manual peel test shows that native silicone does not attach to the fibrin/alginate component while the plasma polymerized silicone membranes are firmly bound to fibrin/alginate. Structural characterization shows that the fibrin/alginate matrix is intact after the addition of the Sil membrane. By adding a Sil membrane to the original fibrin/alginate scaffold, the resulting two-component scaffolds have a significantly higher shear or storage modulus G'. In vitro cell studies show that dermal fibroblasts remain viable, proliferate, and infiltrate the two-component hybrid scaffolds during the culture period. These results show that the design of a novel two-component hybrid dermal scaffold is successful according to the proposed design criteria. To the best of the authors' knowledge, this is the first study that reports the combination of a fibrin-based scaffold with a plasma-polymerized silicone membrane. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Foreign Body Granulomas after the Use of Dermal Fillers: Pathophysiology, Clinical Appearance, Histologic Features, and Treatment

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Jeong Min Lee

2015-03-01

Full Text Available A foreign body granuloma is a non-allergic chronic inflammatory reaction that is mainly composed of multinucleated giant cells. Foreign body granulomas may occur after the administration of any dermal filler. Factors such as the volume of the injection, impurities present in the fillers, and the physical properties of fillers affect granuloma formation. The formation of granulomas involves five phases: protein adsorption, macrophage adhesion, macrophage fusion, and crosstalk. The clinical and pathologic features of granulomas vary depending on the type of filler that causes them. Foreign body granulomas can be treated effectively with intralesional corticosteroid injections. Surgical excisions of granulomas tend to be incomplete because granulomas have ill-defined borders and moreover, surgical excisions may leave scars and deformities.

Nano-titanium dioxide modulates the dermal sensitization potency of DNCB

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Hussain Salik

2012-05-01

Full Text Available Abstract We determined the ability of a model nanoparticle (NP (titanium dioxide, TiO2 to modulate sensitization induced by a known potent dermal sensitizer (dinitrochlorobenzene using a variant of the local lymph node assay called lymph node proliferation assay. BALB/c mice received sub-cutaneous injections of vehicle (2.5 mM sodium citrate, TiO2 NPs (0.004, 0.04 or 0.4 mg/ml or pigment particles (0.04 mg/ml both stabilized in sodium citrate buffer at the base of each ear (2x50μl, before receiving dermal applications (on both ears of 2,4-Dinitrochlorobenzene (DNCB (2x25μl of 0.1% or its vehicle (acetone olive oil – AOO (4:1 on days 0, 1 and 2. On day 5, the stimulation index (SI was calculated as a ratio of 3HTdR incorporation in lymphocytes from DNBC-treated mice and AOO-treated controls. In a second experiment the EC3-value for DNCB (0 to 0.1% was assessed in the absence or presence of 0.04 mg/ml TiO2. In a third experiment, the lymphocyte subpopulations and the cytokine secretion profile were analyzed after TiO2 (0.04 mg/ml and DNCB (0.1% treatment. Injection of NPs in AOO-treated control mice did not have any effect on lymph node (LN proliferation. DNCB sensitization resulted in LN proliferation, which was further increased by injection of TiO2 NPs before DNCB sensitization. The EC3 of DNCB, with prior injection of vehicle control was 0.041%, while injection with TiO2 decreased the EC3 of DNCB to 0.015%. TiO2 NPs pre-treatment did not alter the lymphocyte subpopulations, but significantly increased the level of IL-4 and decreased IL-10 production in DNCB treated animals. In conclusion, our study demonstrates that administration of nano-TiO2 increases the dermal sensitization potency of DNCB, by augmenting a Th2 response, showing the immunomodulatory abilities of NPs.

Cell-mediated immune suppression effect of rocket kerosene through dermal exposure in mice

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Bing-xin XU

2015-10-01

Full Text Available Objective　To study the effect of cell-mediated immune suppression effect of rocket kerosene (RK through dermal application in mice. Methods　Skin delayed type hypersensitivity (DTH was used to observe the relation of the RK amount the skin exposed and the cellular immune inhibitory function. Different amount of the undiluted fuel was smeared directly onto the dorsal skin of mice. Mice in negative and positive control groups were treated with acetone. After the last exposure, all the mice except those in negative control group were allergized by evenly smearing with 1% dinitrofluorobenzene (DNFB solution on their dorsum. Five days after allergy, 1% DNFB solution was smeared onto right ear of all mice to stimulate the allergic reaction. Twenty-four hours after attack, the auricle swelling, spleen index and thymus index in corresponding mice were determined. In the first series of experiments, different dosages of RK were applied once, and the ICR mice were randomly divided into negative control group, positive control group and experimental group (0.5ml/kg.BW×1, 1ml/kg.BW×1 and 2ml/kg.BW×1 group. In the second series of experiments, the certain and same dosage of RK was applied for different times, and the ICR mice were randomly divided into negative control group, positive control group and experimental group (0.5ml/kg.BW×1, 0.5mL/kg.BW×2, 0.5ml/kg.BW×3, 0.5ml/kg.BW×4 and 0.5mL/kg.BW×5 group. In the third series of experiments, the different dosages of RK were applied more than once, and the ICR mice were randomly divided into negative control group, positive control group and experimental group (0.5ml/kg.BW×5, 1ml/kg.BW×5 and 2ml/kg.BW×5 group. Lymphocyte proliferation experiment in vitrowas conducted to observe the persistent time of the cell-mediated immune suppression in mice by RK dermal exposure. The lymphocyte proliferation induced by concanavalin A (Con A was analyzed by MTT assay, and T lymphocyte subsets (CD3+, CD4+ and CD

Histological changes to the skin of Merino sheep following deep dermal and subcutaneous injections of sodium lauryl sulfate.

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Lee, E J; Rothwell, J T

2010-04-01

To characterise the changes caused to sheep skin by deep dermal and subcutaneous injections of sodium lauryl sulfate (SLS) and describe the subsequent healing process. On 6 sheep 20 small areas of skin were each given deep dermal and subcutaneous injections of 0.2 mL of 7% SLS. Biopsies were collected at intervals up to 28 days after treatment and the histological changes in each of the treated skin samples were assessed and graded. There was no evidence of alterations in behaviour, weight gain or appetite of the sheep following the injections. Initial swelling of the treated site subsided by day 14, leaving a firm, slightly raised crust. At day 21, the treated area was depressed and covered by a scab, which sloughed completely by day 28. There was necrosis of the subcutis and deep dermis 2 min after treatment, followed by inflammation, fibroplasia, angiogenesis and tissue remodelling. Injection of SLS caused almost immediate local necrosis followed by eschar formation, sloughing and scarring of treated skin. Deep dermal and subcutaneous SLS is potentially useful as a chemical alternative to mulesing.

The use of a dermal substitute and thin skin grafts in the cure of "complex" leg ulcers.

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Canonico, Silvestro; Campitiello, Ferdinando; Della Corte, Angela; Fattopace, Andrea

2009-02-01

In some chronic leg ulcers, a reconstructive operation using skin grafts may be extremely difficult or is quite likely to fail as a result of the position, the width, and the depth of the lesions. To evaluate the effectiveness of a dermal substitute and thin skin grafts in the treatment of patients suffering from deep and wide chronic leg ulcers. Twenty-six consecutive patients with leg ulcers at least 1 year old were admitted to the study. The ulcers were large (>100 cm2) and deep (>3 mm) over at least 50% of the surface area. After surgical debridement of the wounds, the dermal matrix was modeled and applied. After 21 days, the attachment of the artificial dermis was tested, and in positive cases, the patient was re-admitted for "thin" skin grafting. In all patients, at the first follow-up, a notable reduction in pain, exudate, and perilesional edema was ascertained. After 2 weeks, the progressive substitution of granulation tissue with new yellow or gold derma became evident in all patients. After 21 days, the dermal matrix was completely integrated with the guest tissue. In 23 patients (88.5%), attachment of the skin graft was complete, and in three patients (11.5%), it was partial but nevertheless larger than 70% of the surface. Even in these cases, complete healing of the lesions was achieved within 4 weeks at most. All patients were checked for a minimum of 3 months, and none suffered an ulcerous recurrence. In our series, the use of this dermal matrix allowed for the complete refilling of the loss of tissue, the rapid disappearance of pain, and the rapid regeneration of a permanent dermis.

PBTK modeling demonstrates contribution of dermal and inhalation exposure components to end-exhaled breath concentrations of naphthalene.

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Kim, David; Andersen, Melvin E; Chao, Yi-Chun E; Egeghy, Peter P; Rappaport, Stephen M; Nylander-French, Leena A

2007-06-01

Dermal and inhalation exposure to jet propulsion fuel 8 (JP-8) have been measured in a few occupational exposure studies. However, a quantitative understanding of the relationship between external exposures and end-exhaled air concentrations has not been described for occupational and environmental exposure scenarios. Our goal was to construct a physiologically based toxicokinetic (PBTK) model that quantitatively describes the relative contribution of dermal and inhalation exposures to the end-exhaled air concentrations of naphthalene among U.S. Air Force personnel. The PBTK model comprised five compartments representing the stratum corneum, viable epidermis, blood, fat, and other tissues. The parameters were optimized using exclusively human exposure and biological monitoring data. The optimized values of parameters for naphthalene were a) permeability coefficient for the stratum corneum 6.8 x 10(-5) cm/hr, b) permeability coefficient for the viable epidermis 3.0 x 10(-3) cm/hr, c) fat:blood partition coefficient 25.6, and d) other tissue:blood partition coefficient 5.2. The skin permeability coefficient was comparable to the values estimated from in vitro studies. Based on simulations of workers' exposures to JP-8 during aircraft fuel-cell maintenance operations, the median relative contribution of dermal exposure to the end-exhaled breath concentration of naphthalene was 4% (10th percentile 1% and 90th percentile 11%). PBTK modeling allowed contributions of the end-exhaled air concentration of naphthalene to be partitioned between dermal and inhalation routes of exposure. Further study of inter- and intraindividual variations in exposure assessment is required to better characterize the toxicokinetic behavior of JP-8 components after occupational and/or environmental exposures.

Dermal collagen and lipid deposition correlate with tissue swelling and hydraulic conductivity in murine primary lymphedema.

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Rutkowski, Joseph M; Markhus, Carl Erik; Gyenge, Christina C; Alitalo, Kari; Wiig, Helge; Swartz, Melody A

2010-03-01

Primary lymphedema is a congenital pathology of dysfunctional lymphatic drainage characterized by swelling of the limbs, thickening of the dermis, and fluid and lipid accumulation in the underlying tissue. Two mouse models of primary lymphedema, the Chy mouse and the K14-VEGFR-3-Ig mouse, both lack dermal lymphatic capillaries and exhibit a lymphedematous phenotype attributable to disrupted VEGFR-3 signaling. Here we show that the differences in edematous tissue composition between these two models correlated with drastic differences in hydraulic conductivity. The skin of Chy mice possessed significantly higher levels of collagen and fat, whereas K14-VEGFR-3-Ig mouse skin composition was relatively normal, as compared with their respective wild-type controls. Functionally, this resulted in a greatly increased dermal hydraulic conductivity in K14-VEGFR3-Ig, but not Chy, mice. Our data suggest that lymphedema associated with increased collagen and lipid accumulation counteracts an increased hydraulic conductivity associated with dermal swelling, which in turn further limits interstitial transport and swelling. Without lipid and collagen accumulation, hydraulic conductivity is increased and overall swelling is minimized. These opposing tissue responses to primary lymphedema imply that tissue remodeling--predominantly collagen and fat deposition--may dictate tissue swelling and govern interstitial transport in lymphedema.

Short-term dermal exposure to tannery effluent does not cause behavioral changes in male Swiss mice

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Bruna de Oliveira Mendes

2018-02-01

Full Text Available Tannery is a highly polluting activity due to the waste generated by bovine skin processing. Although there are several studies highlighting the health issues faced by workers exposed to tannery effluent, there are no records of experiments testing the neurobehavioral effects resulting from direct contact with this pollutant. Thus, the aim of the current study is to assess the possible neurobehavioral effects of dermal exposure to tannery effluent on male Swiss mice. Animals were divided in three groups, which were subjected to the same experimental time period and conditions: effluent group - animals in direct contact with tannery effluent (for 20 days; control group - animals in contact with pure water; and dry-control group - animals not exposed to water or to tannery effluent. Neurobehavioral tests started on the 17th experimental day. Results of the elevated plus-maze test (anxiety prediction showed no anxiogenic or anxiolytic effects, memory deficit or depressive symptoms on animals exposed to tannery effluent. Thus, the current results do not support the hypothesis that male Swiss mice dermal exposure to tannery effluents for the same time period and experimental conditions leads to neurobehavioral changes. Therefore, the herein adopted exposure protocol was not good to study the effects of dermal exposure to tannery effluent on the chosen experimental model.

Development of nanovesicular systems for dermal imiquimod delivery: physicochemical characterization and in vitro/in vivo evaluation.

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Ma, Man; Wang, Jinping; Guo, Fang; Lei, Mingzhu; Tan, Fengping; Li, Nan

2015-06-01

The aim of the current investigation was to develop and statistically evaluate nanovesicular systems for dermal imiquimod delivery. To this purpose, transethosomes were prepared with phospholipid, ethanol and different permeation enhancers. Conventional ethosomes, with soy phospholipid and ethanol, were used as control. The prepared vesicles were characterized for size, zeta potential, stability and entrapment efficiency. The optimal transethosomal formulation with mean particle size of 82.3 ± 9.5 nm showed the higher entrapment efficiency (68.69 ± 1.7%). In vitro studies, permeation results of accumulated drug and local accumulation efficiency were significantly higher for transethosomes (24.64 µg/cm(2) and 6.70, respectively) than control (14.45 µg/cm(2) and 3.93, respectively). Confocal laser scanning microscopy of rhodamine 6G-loaded transethosomes revealed an enhanced retention into the deeper skin layers as compared to conventional ethosomes. Besides, Fourier-transform infra-red spectroscopy studies were also performed to understand the mechanism of interaction between skin and carriers. What's more, results of in vivo studies indicated the transethosomes of imiquimod providing the most effectiveness for dermal delivery among all of the formulations. These results suggested that transethosomes would be a promising dermal carrier for imiquimod in actinic keratose treatment.

Osteopathia striata: A characteristic X-ray finding in focal dermal hypoplasia (Goltz-Gorlin syndrome)

International Nuclear Information System (INIS)

Barthels, W.; Boepple, D.; Petzel, H.

1982-01-01

Two cases of the very rare Goltz-Gorlin syndrome are presented. The relationship of osteopathia striata and focal dermal hypoplasia is discussed, and it is concluded that the osteopathia striata represents the characteristic picture of this ectopic mesodermal abnormality. (orig.)

In vitro degradation of dermal sheep collagen cross-linked using a water-soluble carbodiimide

NARCIS (Netherlands)

Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

Bacterial collagenase was used to study the susceptibility of dermal sheep collagen (DSC) cross-inked with a mixture of the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide (EIN-DSC) towards enzymatic degradation. Contrary to

In-vivo dermal pharmacokinetics, efficacy, and safety of skin targeting nanoparticles for corticosteroid treatment of atopic dermatitis.

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Siddique, Muhammad Irfan; Katas, Haliza; Amin, Mohd Cairul Iqbal Mohd; Ng, Shiow-Fern; Zulfakar, Mohd Hanif; Jamil, Adawiyah

2016-06-30

The objective of this study was to investigate the in-vivo behavior of topically applied cationic polymeric chitosan nanoparticles (CSNPs) loaded with anti-inflammatory (hydrocortisone, HC) and antimicrobial (hydroxytyrosol, HT) drugs, to elucidate their skin targeting potential for the treatment of atopic dermatitis (AD). Compared to the commercial formulation, the HC-HT loaded CSNPs showed significantly improved drug penetration into the epidermal and dermal layers of albino Wistar rat skin without saturation. Dermal pharmacokinetic of CSNPs with a size of 228.5±7nm and +39±5mV charges revealed that they penetrated 2.46-fold deeper than the commercial formulation did, and had greater affinity at the skin target site without spreading to the surrounding tissues, thereby providing substantial safety benefits. In repeated dermal application toxicity studies, the HC-HT CSNPs showed no evidence of toxicity compared to the commercial formulation, which induced skin atrophy and higher liver enzyme levels. In conclusion, the positively charged HC-HT CSNP formulation exhibited promising local delivery and virtually no treatment-related toxicities, suggesting it may be an efficient and viable alternative for commercially available AD treatments. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluating the Effectiveness of Cryopreserved Acellular Dermal Matrix in Immediate Expander-Based Breast Reconstruction: A Comparison Study

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So-Young Kim

2015-05-01

Full Text Available BackgroundCGCryoDerm was first introduced in 2010 and offers a different matrix preservation processes for freezing without drying preparation. From a theoretical perspective, CGCryoDerm has a more preserved dermal structure and more abundant growth factors for angiogenesis and recellularization. In the current study, the authors performed a retrospective study to evaluate freezing- and freeze-drying-processed acellular dermal matrix (ADM to determine whether any differences were present in an early complication profile.MethodsPatients who underwent ADM-assisted tissue expander placement for two stage breast reconstruction between January of 2013 and March of 2014 were retrospectively reviewed and divided into two groups based on the types of ADM-assisted expander reconstruction (CGDerm vs. CGCryoDerm. Complications were divided into four main categories and recorded as follows: seroma, hematoma, infection, and mastectomy skin flap necrosis.ResultsIn a total of 82 consecutive patients, the CGCryoDerm group had lower rates of seroma when compared to the CGDerm group without statistical significance (3.0% vs. 10.2%, P=0.221, respectively. Other complications were similar in both groups. Reconstructions with CGCryoDerm were found to have a significantly longer period of drainage when compared to reconstructions with CGDerm (11.91 days vs. 10.41 days, P=0.043.ConclusionsPreliminary findings indicate no significant differences in early complications between implant/expander-based reconstructions using CGCryoderm and those using CGDerm.

Immunopathology of post kala-azar dermal leishmaniasis (PKDL): T-cell phenotypes and cytokine profile

DEFF Research Database (Denmark)

Ismail, A; El Hassan, A M; Kemp, K

1999-01-01

In Sudan, post kala-azar dermal leishmaniasis (PKDL) caused by Leishmania donovani develops in half of the patients treated for visceral leishmaniasis (kala-azar). In most patients lesions heal spontaneously, but in others symptoms are severe and persist for years. This study examined...

Appraisal of the sensitising potential of orally and dermally administered mercaptobenzothiazole by a biphasic protocol of the local lymph node assay.

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Ahuja, Varun; Wanner, Reinhard; Platzek, Thomas; Stahlmann, Ralf

2009-10-01

Mercaptobenzothiazole (MBT) is used while manufacturing natural rubber products. Our study deals with assessing its allergenic potential following dermal and oral routes of exposure, using a biphasic local lymph node assay (LLNA). Female Balb/c mice were treated with MBT (dermally 3, 10, 30% concentrations in DMSO; orally 1, 10, 100 mg/kg doses in corn oil) on the back (dermal study) or through oral administration (oral study) on days 1-3 followed by auricular application of 3, 10 and 30% concentrations, respectively, on days 15-17. End points determined on day 19 included ear thickness, ear punch weight, lymph node weight, lymph node cell count, and lymphocyte subpopulations (CD4+, CD8+, CD45+). After dermal application of 3% or 10% solution, a significant increase in cell count and lymph node weight along with significant decrease in CD8+ cells was observed. After initial oral administration of 1 mg/kg, we noticed a significant amplification in cell count. Following oral administration of 10 mg/kg, we observed a similar increase in cell count and lymph node weight. The results of our study show that the modified biphasic LLNA protocol can be used to study the sensitising potential of a compound also following the oral route of exposure.

Use of Ir192 interstitial brachytherapy for an equine malignant dermal schwannoma : clinical communication

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M.N. Saulez

2009-05-01

Full Text Available A 10-year-old Hanoverian mare was evaluated for a right buccal swelling that recurred 3 months following surgical resection. Ultrasonographic examination showed a broadly pedunculated subcutaneous mass at the level of 106-109 and 406-409 cheek teeth associated with an erosive mucosal lesion on the inside of the cheek. Histological examination of a biopsy specimen revealed a well-demarcated, malignant, dermal schwannoma. Following subcutaneous placement of platinum coated Ir192 wires under general anaesthesia, low-dose radiation of 5 gray per day was delivered for 14 days. Short-term complications included loss of patency of the right nasolacrimal duct, erythema, dermatitis, leukotrichia and left-sided deviation of the muzzle. Ten months later, there has been no tumour recurrence. Findings suggest that the use of interstitial brachytherapy should be considered for a malignant, dermal schwannoma that has recurred or is not amenable to surgery.

Blaschko Linear Enamel Defects - A Marker for Focal Dermal Hypoplasia: Case Report of Focal Dermal Hypoplasia

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Stefan Gysin

2015-05-01

Full Text Available Focal dermal hypoplasia (FDH is a rare genetic skin disorder. The inheritance of FDH or Goltz-Gorlin syndrome is X-linked dominant and the disease is associated with a PORCN gene mutation. This gene plays a key role in the Wnt pathway, which has an impact on embryonic development. Every tissue derived from meso- and ectoderm can be affected. Patients suffer from cutaneous, ocular, osseous, oral and dental defects. The skin and dental alterations manifest along the Blaschko lines. We present a woman (born in 1962 suffering from FDH with congenital skin changes and Blaschko linear enamel defects. Typical symptoms (e.g. fat herniations, scoliosis, syndactyly, microphthalmia, caries and alopecia plus vertical grooving of all teeth gave a first indication. Molecular genetic testing confirmed the definitive diagnosis of FDH. We hypothesize that, in the context of typical skin changes, visible Blaschko lines on the teeth in the form of vertical grooves are almost pathognomonic for FDH.

Emblica extract prevents cisplatin-induced apoptosis in dermal papilla fibroblasts

OpenAIRE

Sudjit Luanpitpong; Varisa Pongrakhananon; Ubonthip Nimmannit; Pithi Chanvorachote

2008-01-01

Cisplatin is a widely prescribed anticancer agent that causes hair loss in patients. Since the dermal papilla (DP) fibroblasts are known to be a key mediator in controlling hair growth and loss, understanding the effect and underlying mechanism of cisplatin on these cells may lead to new strategy for hair loss protection in chemotherapy patients. Less is known regarding the effect of cisplatin on DP fibroblasts. We thus treated DP cells with cisplatin (0-250 mmol/L) and found that cisplatin i...

Chondrogenic potential of physically treated bovine cartilage matrix derived porous scaffolds on human dermal fibroblast cells.

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Moradi, Ali; Ataollahi, Forough; Sayar, Katayoun; Pramanik, Sumit; Chong, Pan-Pan; Khalil, Alizan Abdul; Kamarul, Tunku; Pingguan-Murphy, Belinda

2016-01-01

Extracellular matrices have drawn attention in tissue engineering as potential biomaterials for scaffold fabrication because of their bioactive components. Noninvasive techniques of scaffold fabrication and cross-linking treatments are believed to maintain the integrity of bioactive molecules while providing proper architectural and mechanical properties. Cartilage matrix derived scaffolds are designed to support the maintenance of chondrocytes and provide proper signals for differentiation of chondroinducible cells. Chondroinductive potential of bovine articular cartilage matrix derived porous scaffolds on human dermal fibroblasts and the effect of scaffold shrinkage on chondrogenesis were investigated. An increase in sulfated glycosaminoglycans production along with upregulation of chondrogenic genes confirmed that physically treated cartilage matrix derived scaffolds have chondrogenic potential on human dermal fibroblasts. © 2015 Wiley Periodicals, Inc.

The effect of keratinocytes on the biomechanical characteristics and pore microstructure of tissue engineered skin using deep dermal fibroblasts.

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Varkey, Mathew; Ding, Jie; Tredget, Edward E

2014-12-01

Fibrosis affects most organs, it results in replacement of normal parenchymal tissue with collagen-rich extracellular matrix, which compromises tissue architecture and ultimately causes loss of function of the affected organ. Biochemical pathways that contribute to fibrosis have been extensively studied, but the role of biomechanical signaling in fibrosis is not clearly understood. In this study, we assessed the effect keratinocytes have on the biomechanical characteristics and pore microstructure of tissue engineered skin made with superficial or deep dermal fibroblasts in order to determine any biomaterial-mediated anti-fibrotic influences on tissue engineered skin. Tissue engineered skin with deep dermal fibroblasts and keratinocytes were found to be less stiff and contracted and had reduced number of myofibroblasts and lower expression of matrix crosslinking factors compared to matrices with deep fibroblasts alone. However, there were no such differences between tissue engineered skin with superficial fibroblasts and keratinocytes and matrices with superficial fibroblasts alone. Also, tissue engineered skin with deep fibroblasts and keratinocytes had smaller pores compared to those with superficial fibroblasts and keratinocytes; pore size of tissue engineered skin with deep fibroblasts and keratinocytes were not different from those matrices with deep fibroblasts alone. A better understanding of biomechanical characteristics and pore microstructure of tissue engineered skin may prove beneficial in promoting normal wound healing over pathologic healing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dermal phospho-alpha-synuclein deposits confirm REM sleep behaviour disorder as prodromal Parkinson's disease

NARCIS (Netherlands)

Doppler, Kathrin; Jentschke, Hanna-Maria; Schulmeyer, Lena; Vadasz, David; Janzen, Annette; Luster, Markus; Höffken, Helmut; Mayer, Geert; Brumberg, Joachim; Booij, Jan; Musacchio, Thomas; Klebe, Stephan; Sittig-Wiegand, Elisabeth; Volkmann, Jens; Sommer, Claudia; Oertel, Wolfgang H.

2017-01-01

Phosphorylated alpha-synuclein (p-alpha-syn) deposits, one of the neuropathological hallmarks of Parkinson's disease (PD), have recently been detected in dermal nerve fibres in PD patients with good specificity and sensitivity. Here, we studied whether p-alpha-syn may serve as a biomarker in

Application of dermal microdialysis for the evaluation of bioequivalence of a ketoprofen topical gel

DEFF Research Database (Denmark)

Tettey-Amlalo, Ralph Nii Okai; Kanfer, Isadore; Skinner, Michael F

2008-01-01

The purpose was to investigate dermal microdialysis (DMD) for the assessment of the bioavailability of a ketoprofen topical gel formulation and to evaluate this technique as a tool for the determination of bioequivalence. Four microdialysis probes were inserted into the dermis on the volar aspect...

Dermal regeneration in native non-cross-linked collagen sponges with different extracellular matrix molecules

NARCIS (Netherlands)

de Vries, H. J.; Middelkoop, E.; Mekkes, J. R.; Dutrieux, R. P.; Wildevuur, C. H.; Westerhof, H.

1994-01-01

Collagenous dermal templates can prevent scarring and wound contraction in the healing of full-thickness defects. In a porcine wound model, full-thickness wounds were substituted by reconstituted and native collagen sponges in combination with autologous split-skin mesh grafts and covered with a

The processing of sheepskin for use as a dermal collagen graft--an experimental study

NARCIS (Netherlands)

van Gulik, T. M.; Klopper, P. J.

1987-01-01

In search of a biological mesh-prosthesis, sheepskin was processed according to established methods in the manufacture of leather. The dermal collagen fibre-mesh of sheepskin was purified by a proteolytic enzyme treatment after which the skins were split, providing a split-skin graft corresponding

The discrimination of some dermal dischromias using the ESR and NAA

International Nuclear Information System (INIS)

Georgescu, Rodica; Saidel, Alice; Cristodulo, Tania; Saidel, M.

1997-01-01

The information provided by the electron spin resonance (ESR) and neutron activation analysis (NAA) seem to complete each other most of time. ESR is applied in biology, due to its significant sensitivity and selectivity in the detection of paramagnetic states of free radicals implied in many physiological processes. Many enzymatic systems, photosynthesis intermediates or electrons transporting chain species are paramagnetic. On the other hand, free radicals are involved in the protection against ionic radiation, in immunity reactions and pathological processes including the oncogenesis. ESR spectroscopy informs about the quantity, interactions and dynamics of paramagnetic centres of the systems through spectral parameters as: the intensity, the g factor, the form and the width of line, hyperfine splitting, etc. NAA allows simultaneous determination of the concentration of essential microelements in tissues involved in the major biological pathways. In the present work we have tested the possibility of using the ESR and NAA investigations techniques combined with the factorial statistic analysis of the data, in the aim to discriminate some dermal dischromias of human skin. Having in view that the hyper- and hipochromia are due to an excess and deficit in melanin, respectively, we used ESR to observe the radical species from the skin samples. We studied the skin samples that represent different dischromias (malign melanoma, epithelioma, pigmentary nevus, vitiligo) in comparison with normal skin. On the same samples we have determined by NAA the concentrations of elements (Cu, Na, Mg, Mn, and Al) which could be involved in the mechanisms of producing and releasing the melanin. The signal ESR intensities and widths and the NAA elemental concentration values of the skin samples have been processed by a STATCF program to develop differences between dischromic and normal skin. The signification level of the differences observed among the sample groups has been evaluated

Microporous dermal-like electrospun scaffolds promote accelerated skin regeneration.

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Bonvallet, Paul P; Culpepper, Bonnie K; Bain, Jennifer L; Schultz, Matthew J; Thomas, Steven J; Bellis, Susan L

2014-09-01

The goal of this study was to synthesize skin substitutes that blend native extracellular matrix (ECM) molecules with synthetic polymers which have favorable mechanical properties. To this end, scaffolds were electrospun from collagen I (col) and poly(ɛ-caprolactone) (PCL), and then pores were introduced mechanically to promote fibroblast infiltration, and subsequent filling of the pores with ECM. A 70:30 col/PCL ratio was determined to provide optimal support for dermal fibroblast growth, and a pore diameter, 160 μm, was identified that enabled fibroblasts to infiltrate and fill pores with native matrix molecules, including fibronectin and collagen I. Mechanical testing of 70:30 col/PCL scaffolds with 160 μm pores revealed a tensile strength of 1.4 MPa, and the scaffolds also exhibited a low rate of contraction (pores. Keratinocytes formed a stratified layer on the surface of fibroblast-remodeled scaffolds, and staining for cytokeratin 10 revealed terminally differentiated keratinocytes at the apical surface. When implanted, 70:30 col/PCL scaffolds degraded within 3-4 weeks, an optimal time frame for degradation in vivo. Finally, 70:30 col/PCL scaffolds with or without 160 μm pores were implanted into full-thickness critical-sized skin defects. Relative to nonporous scaffolds or sham wounds, scaffolds with 160 μm pores induced accelerated wound closure, and stimulated regeneration of healthy dermal tissue, evidenced by a more normal-appearing matrix architecture, blood vessel in-growth, and hair follicle development. Collectively, these results suggest that microporous electrospun scaffolds are effective substrates for skin regeneration.

A microanatomical and histological study of the postcranial dermal skeleton of the Devonian actinopterygian Cheirolepis canadensis

Directory of Open Access Journals (Sweden)

Louise Zylberberg

2016-06-01

Full Text Available The Devonian stem-actinoterygian Cheirolepis canadensis is potentially important to understand the evolution of the dermal skeleton of osteichthyans, but the last detailed histological study on this taxon was published more than forty years ago. Here, we present new data about the morphology and the histological structure of scales, fulcra, and fin-rays in the Devonian actinopterygian Cheirolepis canadensis through SEM and photomicroscopy. The scales have a typical palaeoniscoid organisation, with ganoine layers overlaying dentine and a bony basal plate, but the ganoine surface lacks the characteristic microtubercles that have been described on the ganoine surface of the scales of polypterids and many other actinopterygians. Fin-rays are composed of segmented and ramified lepidotrichia that show a structure reminiscent of scales, with ganoine and dentine components lying on a thick bony base. We describe articular processes between lepidotrichia that are reminiscent of, and plausibly homologous with, the peg-and-socket articulations between the scales. The analysis of the postcranial dermal skeleton of Cheirolepis canadensis shows that structural similarities between scales and lepidotrichia of this basal actinopterygian are greater than in more recent actinopterygians. The new data on histological and microanatomical structure of the dermal skeleton lend additional support to the hypothesis that lepidotichia are derivatives of scales, though they are also compatible with the more general hypothesis that scales, lepidotrichia and fulcra belong to the same morphogenetic system.

Modeled exposure assessment via inhalation and dermal pathways to airborne semivolatile organic compounds (SVOCs) in residences.

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Shi, Shanshan; Zhao, Bin

2014-05-20

Exposure to airborne semivolatile organic compounds (SVOCs) in indoor and outdoor environments of humans may lead to adverse health risks. Thus, we established a model to evaluate exposure to airborne SVOCs. In this model, SVOCs phase-specific concentrations were estimated by a kinetic partition model accounting for particle dynamics. The exposure pathways to airborne SVOCs included inhalation exposure to gas- and particle-phases, dermal exposure by direct gas-to-skin pathway and dermal exposure by direct particle deposition. Exposures of defined "reference people" to two typical classifications of SVOCs, one generated from both indoor and outdoor sources, represented by polycyclic aromatic hydrocarbons (PAHs), and the other generated mainly from only indoor sources, represented by di 2-ethylhexyl phthalate (DEHP), were analyzed as an example application of the model. For PAHs with higher volatility, inhalation exposure to gas-phase, ranging from 6.03 to 16.4 ng/kg/d, accounted for the most of the exposure to the airborne phases. For PAHs with lower volatility, inhalation exposure to particle-phase, ranging from 1.48 to 1.53 ng/kg/d, was the most important exposure pathway. As for DEHP, dermal exposure via direct gas-to-skin pathway was 460 ng/kg/d, which was the most striking exposure pathway when the barrier effect of clothing was neglected.

Sterile Acellular Dermal Collagen as a Treatment for Rippling Deformity of Breast

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Brittany Busse

2014-01-01

Full Text Available Prosthetic implants are frequently used for breast augmentation and breast reconstruction following mastectomy. Unfortunately, long-term aesthetic results of prosthetic breast restoration may be hindered by complications such as rippling, capsular contracture, and implant malposition. The advent of use of acellular dermal matrices has greatly improved the outcomes of prosthetic breast reconstruction. We describe a case of rippling deformity of breast that was treated using an acellular dermal matrix product, AlloMax. The patient presented with visible rippling of bilateral prosthetic breast implants as well as significant asymmetry of the breasts after multiple excisional biopsies for right breast ductal carcinoma in situ. A 6×10 cm piece of AlloMax was placed on the medial aspect of each breast between the implant and the skin flap. Follow-up was performed at 1 week, 3 months, and 1 year following the procedure. The patient recovered well from the surgery and there were no complications. At her first postoperative follow-up the patient was extremely satisfied with the result. At her 3-month and 1-year follow-up she had no recurrence of her previous deformity and no new deformity.

Dermal oncogenicity bioassays of monofunctional and multifunctional acrylates and acrylate-based oligomers.

Science.gov (United States)

DePass, L R; Maronpot, R R; Weil, C S

1985-01-01

Several important components of photocurable coatings were studied for dermal tumorigenic activity by repeated application to the skin of mice. The substances tested were 2-ethylhexyl acrylate (EHA) and methylcarbamoyloxyethyl acrylate (MCEA) (monomers); neopentyl glycol diacrylate (NPGDA), esterdiol-204-diacrylate (EDDA), and pentaerythritol tri(tetra)acrylate (PETA) (cross-linkers); and three acrylated urethane oligomers. For each bioassay, 40 C3H/HeJ male mice were dosed 3 times weekly on the dorsal skin for their lifetime with the highest dose of the test agent that caused no local irritation or reduction in body weight gain. Two negative control groups received acetone (diluent) only. A positive control group received 0.2% methylcholanthrene (MC). NPGDA and EHA had significant tumorigenic activity with tumor yields of eight and six tumor-bearing mice (three and two malignancies), respectively. The MC group had 34 mice with carcinomas and 1 additional mouse with a papilloma. MCEA had no dermal tumorigenic activity but resulted in early mortality. No skin tumors in the treatment area were observed in the other groups. Additional studies will be necessary to elucidate possible relationships between structure and tumorigenic activity for the acrylates.

A titanium surface with nano-ordered spikes and pores enhances human dermal fibroblastic extracellular matrix production and integration of collagen fibers

International Nuclear Information System (INIS)

Yamada, Masahiro; Kato, Eiji; Sakurai, Kaoru; Yamamoto, Akiko

2016-01-01

The acquisition of substantial dermal sealing determines the prognosis of percutaneous titanium-based medical devices or prostheses. A nano-topographic titanium surface with ordered nano-spikes and pores has been shown to induce periodontal-like connective tissue attachment and activate gingival fibroblastic functions. This in vitro study aimed to determine whether an alkali-heat (AH) treatment-created nano-topographic titanium surface could enhance human dermal fibroblastic functions and binding strength to the deposited collagen on the titanium surface. The surface topographies of commercially pure titanium machined discs exposed to two different AH treatments were evaluated. Human dermal fibroblastic cultures grown on the discs were evaluated in terms of cellular morphology, proliferation, extracellular matrix (ECM) and proinflammatory cytokine synthesis, and physicochemical binding strength of surface-deposited collagen. An isotropically-patterned, shaggy nano-topography with a sponge-like inner network and numerous well-organized, anisotropically-patterned fine nano-spikes and pores were observed on each nano-topographic surface type via scanning electron microscopy. In contrast to the typical spindle-shaped cells on the machined surfaces, the isotropically- and anisotropically-patterned nano-topographic titanium surfaces had small circular/angular cells containing contractile ring-like structures and elongated, multi-shaped cells with a developed cytoskeletal network and multiple filopodia and lamellipodia, respectively. These nano-topographic surfaces enhanced dermal-related ECM synthesis at both the protein and gene levels, without proinflammatory cytokine synthesis or reduced proliferative activity. Deposited collagen fibers were included in these surfaces and sufficiently bound to the nano-topographies to resist the physical, enzymatic and chemical detachment treatments, in contrast to machined surfaces. Well-organized, isotropically

Optimizing the dermal accumulation of a tazarotene microemulsion using skin deposition modeling.

Science.gov (United States)

Nasr, Maha; Abdel-Hamid, Sameh

2016-01-01

It is well known that microemulsions are mainly utilized for their transdermal rather than their dermal drug delivery potential due to their low viscosity, and the presence of penetration enhancing surfactants and co-surfactants. Applying quality by design (QbD) principles, a tazarotene microemulsion formulation for local skin delivery was optimized by creating a control space. Critical formulation factors (CFF) were oil, surfactant/co-surfactant (SAA/CoS), and water percentages. Critical quality attributes (CQA) were globular size, microemulsion viscosity, tazarotene skin deposition, permeation, and local accumulation efficiency index. Increasing oil percentage increased globular size, while the opposite occurred regarding SAA/CoS, (p = 0.001). Microemulsion viscosity was reduced by increasing oil and water percentages (p microemulsion viscosity, and drug deposition. A combination of 40% oil and 45% SAA/CoS showed the maximum drug deposition of 75.1%. Clinical skin irritation study showed that the aforementioned formula was safe for topical use. This article suggests that applying QbD tools such as experimental design is an efficient tool for drug product design.

Orobanche cernua Loefling Attenuates Ultraviolet B-mediated Photoaging in Human Dermal Fibroblasts.

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Gao, Wei; Wang, Yu-Shuai; Qu, Zheng-Yi; Hwang, Eunson; Ngo, Hien T T; Wang, Ying-Ping; Bae, Jahyun; Yi, Tae-Hoo

2018-02-15

UV radiation is the primary cause of skin photoaging, which results in an increase in matrix metalloproteinases and degradation of collagen. Developing new natural antioxidant as photoprotective agents has become a popular area of research. Orobanche cernua Loefling is a parasitic plant that is rich in phenylethanoid glycosides (PhGs). This study investigated the photoprotective effects of the ethanolic extract of Orobanche cernua Loefling (OC) and its principal component acteoside on UVB-induced photoaging as well as their underlying molecular mechanisms in normal human dermal fibroblasts (NHDFs). Biological testing demonstrated that OC and acteoside possessed significant photoprotective activities, reducing MMP and IL-6 levels while improving type-I procollagen synthesis in UVB-irradiated NHDFs. Further study showed that the protective mechanisms were the improvement of transcription factor Nrf2-mediated antioxidant defensive system, suppression of MAPK/AP-1 and activation of the TGF-β/Smad pathway. Together, our results suggested that OC might be a promising antiphotoaging agent against UV radiation-induced skin damage. © 2018 The American Society of Photobiology.

Atypical post kala azar dermal leishmaniasis with "muzzle area" swelling.

Science.gov (United States)

Arora, Sandeep; Bal, Arvinder Singh; Baveja, Sukriti; Sood, Aradhana; Rathi, Khushi Ram; Patil, Pradeep

2015-01-01

A 50-year-old male presented with recurrent swelling of the muzzle area of the face with history of low-grade intermittent fever of 3 year duration managed variously with antibiotics, systemic steroids, and antituberculous therapy. Skin biopsy revealed a granulomatous infiltration negative for acid-fast bacilli and leishmania donovan bodies. Immunochromatography test for rK 39 antigen and polymerase chain reaction for leishmania was positive. He was diagnosed as a case of post kala azar dermal leishmaniasis, managed with injection sodium stibogluconate and followed-up thereafter.

Cost study of dermal substitutes and topical negative pressure in the surgical treatment of burns

NARCIS (Netherlands)

Hop, M.J.; Bloemen, M.C.T.; van Baar, M.E.; Nieuwenhuis, M.K.; van Zuijlen, P.P.M.; Polinder, S.; Middelkoop, E.

2014-01-01

AbstractBackground A recently performed randomised controlled trial investigated the clinical effectiveness of dermal substitutes (DS) and split skin grafts (SSG) in combination with topical negative pressure (TNP) in the surgical treatment of burn wounds. In the current study, medical and

A Novel Mutation in the Transglutaminase-1 Gene in an Autosomal Recessive Congenital Ichthyosis Patient

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D. Vaigundan

2014-01-01

Full Text Available Structure-function implication on a novel homozygous Trp250/Gly mutation of transglutaminase-1 (TGM1 observed in a patient of autosomal recessive congenital ichthyosis is invoked from a bioinformatics analysis. Structural consequences of this mutation are hypothesized in comparison to homologous enzyme human factor XIIIA accepted as valid in similar structural analysis and are projected as guidelines for future studies at an experimental level on TGM1 thus mutated.

Association of versican with dermal matrices and its potential role in hair follicle development and cycling

DEFF Research Database (Denmark)

du Cros, D L; LeBaron, R G; Couchman, J R

1995-01-01

Versican is a member of the group of aggregating proteoglycans involved in matrix assembly and structure and in cell adhesion. We examined changes in the distribution of versican in mammalian skin, with emphasis on hair follicle development and cycling. In adult human skin, immunostaining...... for versican appeared predominantly in the dermis, with intense staining of the reticular dermis. Weak staining was observed at the dermoepidermal junction and the connective tissue sheath of hair follicles. Versican expression was also noted in the reticular dermis of rat skin, within dermal papillae......, and possibly associated with follicle basement membranes. During mouse hair follicle development, versican was not expressed until the hair follicles were beginning to produce fibers. With follicle maturation, versican expression intensified in the dermal papillae, reaching a maximum at the height...

Enhancement of distribution of dermal multipotent stem cells to bone marrow in rats of total body irradiation by platelet-derived growth factor-AA treatment

International Nuclear Information System (INIS)

Zong Zhaowen; Ren Yongchuan; Shen Yue; Chen Yonghua; Ran Xinze; Shi Chunmeng; Cheng Tianmin

2011-01-01

Objective: To observe whether dermal multipotent stem cells (dMSCs) treated with platelet-derived growth factor-AA (PDGF-AA) could distribute more frequently to the bone marrow in rats of total body irradiation (TBI). Methods: Male dMSCs were isolated and 10 μg/L PDGF-AA was added to the culture medium and further cultured for 2 h. Then the expression of tenascin-C were examined by Western blot, and the migration ability of dMSCs was assessed in transwell chamber. The pre-treated dMSCs were transplanted by tail vein injection into female rats administered with total body irradiation, and 2 weeks after transplantation, real-time PCR was employed to measure the amount of dMSCs in bone marrow. Non-treated dMSCs served as control.Results PDGF-AA treatment increased the expression of tenascin-C in dMSCs, made (1.79 ± 0.13) × 10 5 cells migrate to the lower chamber under the effect of bone marrow extract, and distributed to bone marrow in TBI rats, significantly more than (1.24 ± 0.09) ×10 5 in non-treated dMSCs (t=8.833, P<0.01). Conclusions: PDGF-AA treatment could enhance the migration ability of dMSCs and increase the amount of dMSCs in bone marrow of TBI rats after transplantation. (authors)

Occular and dermal toxicity of Jatropha curcas phorbol esters.

Science.gov (United States)

Devappa, Rakshit K; Roach, Joy S; Makkar, Harinder P S; Becker, Klaus

2013-08-01

Jatropha curcas seeds are a promising feedstock for biodiesel production. However, Jatropha seed oil and other plant parts are toxic due to the presence of phorbol esters (PEs). The ever-increasing cultivation of toxic genotype of J. curcas runs the risk of increased human exposure to Jatropha products. In the present study, effects of J. curcas oil (from both toxic and nontoxic genotypes), purified PEs-rich extract and purified PEs (factors C1, C2, C(3mixture), (C4+C5)) on reconstituted human epithelium (RHE) and human corneal epithelium (HCE) were evaluated in vitro. The PEs were purified from toxic Jatropha oil. In both RHE and HCE, the topical application of PEs containing samples produced severe cellular alterations such as marked oedema, presence of less viable cell layers, necrosis and/or partial tissue disintegration in epithelium and increased inflammatory response (interleukin-1α and prostaglandin E2). When compared to toxic oil, histological alterations and inflammatory response were less evident (PJatropha PEs are toxic towards RHE and HCE models, which represents dermal and occular toxicity respectively. Data obtained from this study would aid in the development of safety procedures for Jatropha biodiesel industries. It is advised to use protective gloves and glasses when handling PEs containing Jatropha products. Copyright © 2013 Elsevier Inc. All rights reserved.

Integra as a Dermal Replacement in a Meshed Composite Skin Graft in a Rat Model: A One-Step Operative Procedure

Science.gov (United States)

2002-01-01

skin graft (MCSG) using Integra as a dermal template for a meshed split thickness autograft was developed in rats. The silicon layer of Integra was removed, the resulting dermal analogue was meshed (1:1.5), expanded, and placed on excised full thickness wound and covered with a meshed (1:1.5 or 1:6) split thickness autograft. Grafted wounds were dressed with BioBrane, Vaseline gauze, silver-impregnated nylon, or silver-nylon and direct current (SNDC). At scheduled intervals up to 3 months postgrafting, wounds were examined for epithelialization, collagen deposition and

Exposure to organophosphate flame retardants in spray polyurethane foam applicators: Role of dermal exposure.

Science.gov (United States)

Bello, Anila; Carignan, Courtney C; Xue, Yalong; Stapleton, Heather M; Bello, Dhimiter

2018-04-01

Spray polyurethane foam (SPF) is a highly effective thermal insulation material that has seen considerable market growth in the past decade. Organophosphate flame retardants (PFRs) are added to SPF formulations to meet fire code requirements. A common flame retardant used in SPF formulations is tris 1-chloro 2-propyl phosphate (TCIPP), a suspected endocrine disruptor. Exposure monitoring efforts during SPF applications have focused primarily on the isocyanate component, a potent respiratory and dermal sensitizer. However, to our knowledge, there is no monitoring data for TCIPP. To characterize occupational exposures to TCIPP and other flame retardants during SPF insulation. Workers at four SPF insulation sites and one foam removal site (total n = 14) were recruited as part of this pilot study. Personal inhalation exposure to TCIPP was monitored with a CIP-10MI inhalable sampler and potential dermal exposure was assessed through the use of a glove dosimeter. Biomarkers of TCIPP and three other PFRs were measured in urine collected from workers pre-and post-shift. Linear mixed effect models were used to analyze associations of urinary biomarkers with inhalation and dermal exposures and paired t-tests were used to examine the difference on the means of urinary biomarkers pre-and post-shift. Chemical analysis of all species was performed with liquid chromatography-electrospray ionization tandem mass spectrometry. Geometric mean (GM) concentrations of TCIPP in personal air monitors and glove dosimeters collected from SPF applicators, 294.7 μg/m 3 and 18.8 mg/pair respectively. Overall, GM concentrations of the two TCIPP urinary biomarkers BCIPP and BCIPHIPP and (6.2 and 88.8 μg/mL) were 26-35 times higher than reported in the general population. Post-shift levels of TCIPP biomarkers were higher than pre-shift even though workers at insulation sites wore supplied air respirators, gloves and coveralls. The urinary biomarkers for the other PFRs were not

Immunotoxicity evaluation of jet a jet fuel in female rats after 28-day dermal exposure.

Science.gov (United States)

Mann, Cynthia M; Peachee, Vanessa L; Trimmer, Gary W; Lee, Ji-Eun; Twerdok, Lorraine E; White, Kimber L

2008-01-01

The potential for jet fuel to modulate immune functions has been reported in mice following dermal, inhalation, and oral routes of exposure; however, a functional evaluation of the immune system in rats following jet fuel exposure has not been conducted. In this study potential effects of commercial jet fuel (Jet A) on the rat immune system were assessed using a battery of functional assays developed to screen potential immunotoxic compounds. Jet A was applied to the unoccluded skin of 6- to 7-wk-old female Crl:CD (SD)IGS BR rats at doses of 165, 330, or 495 mg/kg/d for 28 d. Mineral oil was used as a vehicle to mitigate irritation resulting from repeated exposure to jet fuel. Cyclophosphamide and anti-asialo GM1 were used as positive controls for immunotoxic effects. In contrast to reported immunotoxic effects of jet fuel in mice, dermal exposure of rats to Jet A did not result in alterations in spleen or thymus weights, splenic lymphocyte subpopulations, immunoglobulin (Ig) M antibody-forming cell response to the T-dependent antigen, sheep red blood cells (sRBC), spleen cell proliferative response to anti-CD3 antibody, or natural killer (NK) cell activity. In each of the immunotoxicological assays conducted, the positive control produced the expected results, demonstrating the assay was capable of detecting an effect if one had occurred. Based on the immunological parameters evaluated under the experimental conditions of the study, Jet A did not adversely affect immune responses of female rats. It remains to be determined whether the observed difference between this study and some other studies reflects a difference in the immunological response of rats and mice or is the result of other factors.

Protective role of vitamin E preconditioning of human dermal fibroblasts against thermal stress in vitro.

Science.gov (United States)

Butt, Hira; Mehmood, Azra; Ali, Muhammad; Tasneem, Saba; Anjum, Muhammad Sohail; Tarar, Moazzam N; Khan, Shaheen N; Riazuddin, Sheikh

2017-09-01

Oxidative microenvironment of burnt skin restricts the outcome of cell based therapies of thermal skin injuries. The aim of this study was to precondition human dermal fibroblasts with an antioxidant such as vitamin E to improve their survival and therapeutic abilities in heat induced oxidative in vitro environment. Fibroblasts were treated with 100μM vitamin E for 24h at 37°C followed by heat shock for 10min at 51°C in fresh serum free medium. Preconditioning with vitamin E reduced cell injury as demonstrated by decreased expression of annexin-V, cytochrome p450 (CYP450) mediated oxidative reactions, senescence and release of lactate dehydrogenase (LDH) accomplished by down-regulated expression of pro-apoptotic BAX gene. Vitamin E preconditioned cells exhibited remarkable improvement in cell viability, release of paracrine factors such as epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), stromal derived factor-1alpha (SDF-1α) and also showed significantly up-regulated levels of PCNA, VEGF, BCL-XL, FGF7, FGF23, FLNβ and Col7α genes presumably through activation of phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. The results suggest that pretreatment of fibroblasts with vitamin E prior to transplantation in burnt skin speeds up the wound healing process by improving the antioxidant scavenging responses in oxidative environment of transplanted burn wounds. Copyright © 2017 Elsevier Inc. All rights reserved.

Plasma Rich in Growth Factors Enhances Wound Healing and Protects from Photo-oxidative Stress in Dermal Fibroblasts and 3D Skin Models.

Science.gov (United States)

Anitua, Eduardo; Pino, Ander; Jaen, Pedro; Orive, Gorka

2016-01-01

Optimal skin repair has been a desired goal for many researchers. Recently, plasma rich in growth factors (PRGF) has gained importance in dermatology proving it is beneficial effects in wound healing and cutaneous regeneration. The anti-fibrotic, pro-contractile and photo-protective effect of PRGF on dermal fibroblasts and 3D skin models has been evaluated. The effect against TGFβ1 induced myofibroblast differentiation was tested. Cell contractile activity over collagen gel matrices was analyzed and the effect against UV derived photo-oxidative stress was assessed. The effectiveness of PRGF obtained from young aged and middle aged donors was compared. Furthermore, 3D organotypic skin explants were used as human skin models with the aim of analyzing ex vivo cutaneous preventive and regenerative photo-protection after UV exposure. TGFβ1 induced myofibroblast levels decreased significantly after treatment with PRGF while the contractile activity increased compared to the control group. After UV irradiation, cell survival was promoted while apoptotic and ROS levels were noticeably reduced. Photo-exposed 3D explants showed higher levels of metabolic activity and lower levels of necrosis, cell damage, irritation and ROS formation when treated with PRGF. The histological integrity and connective tissue fibers showed lower signals of photodamage among PRGF injected skin models. No significant differences for the assessed biological outcomes were observed when PRGF obtained from young aged and middle aged donors were compared. These findings suggest that this autologous approach might be useful for antifibrotic wound healing and provide an effective protection against sun derived photo-oxidative stress regardless the age of the patient.

Polypeptide structure of a human dermal fibroblast-activating factor (FAF) derived from the U937 cultured line of human monocyte-like cells

International Nuclear Information System (INIS)

Cooke, M.P.; Allar, W.J.; Goetzl, E.J.; Dohlman, J.G.

1986-01-01

Six liter batches of 1 x 10 6 U937 cells/ml of serum-free RPMI medium were incubated with 100 ng/ml of phorbol myristate acetate for 48 hr at 37 0 C in 5% CO 2 in air to generate FAFs, as quantified by the stimulation of uptake of [ 3 H]thymidine by quiescent human dermal fibroblasts. Filtration of the supernatants on Sephadex G-75 resolved two FAFs of approximately 40,000 and 10-13,000 daltons. The latter principle was purified to homogeneity by sequential Sephadex G-50 filtration, revealing an apparent m.w. of 7-8000, Mono-Q FPLC anion-exchange chromatography with a linear gradient from 20 mM Tris-HCl (pH 8.3) to 0.5 M NaCl-20 mM Tris-HCl in 30 min, and two cycles of high-performance liquid chromatography (HPLC) on a 300 A pore 10 μm C4 column at 1 ml/min with 0.05% trifluoroacetic acid (TFA) in water to 30:70 (v:v) and then to 60:40 (v:v) acetonitrile: 0.05% TFA linearly in 15 min and 30 min, respectively, The FAF activity eluted from HPLC in a sharp peak of O.D. 215 nm at 45% acetonitrile. Analyses of amino acid composition of the highly purified 7-8000 dalton FAF-U937 revealed 37% hydrophobic, 14% basic, and 21% acidic or amide residues, as well as one tryrosine and one methionine. This U937 cell-derived FAF appears to be a unique acidic polypeptide growth factor

Systemic uptake and clearance of chloroform by hairless rats following dermal exposure. I. Brief exposure to aqueous solutions.

Science.gov (United States)

Islam, M S; Zhao, L; Zhou, J; Dong, L; McDougal, J N; Flynn, G L

1996-06-01

The systemic uptake of chloroform from dilute aqueous solutions into live hairless rats under conditions simulating dermal environmental exposure was studied. Whole blood was sampled during a 30-min immersion of an animal within water containing a known concentration of chloroform and then for 5.5 h following its removal from the bath. The amount of chloroform systemically absorbed was determined by comparing the AUCs of the blood concentration vs. time plots from dermal exposure to that obtained after i.v. infusion (for a period of 30 min) of an aqueous solution containing a known amount of chloroform (positive control). Although dermal data implied two-compartment disposition characteristics, i.v. infusion data fit best to a three-compartment disposition. Linear pharmacokinetics was observed both by i.v. administration and percutaneous absorption at the dose levels studied. Chloroform was detected in the rat blood as early as 4 min following exposure. Our findings suggest that about 10.2 mg of chloroform was systemically absorbed after dermal exposure of a rat to an aqueous solution of 0.44 mg/ml. This amount is substantially higher than the predictions of mathematical risk-models put forth by some investigators. However, when expressed as the "effective" permeability coefficient (Kpeff), close agreement was noticed between our value and those estimated by others using physiologically based pharmacokinetic (PBPK) models. Also, in terms of Kpeff, reasonable agreement existed between our and another investigator's past estimates of uptake based on depletion of bath level of chloroform and the actual uptake measured in our current experiments. The estimated onset of systemic entry seen here is entirely consistent with our estimate of how long it takes to establish the diffusion gradient across the stratum corneum based on tape stripping.

GABA promotes elastin synthesis and elastin fiber formation in normal human dermal fibroblasts (HDFs).

Science.gov (United States)

Uehara, Eriko; Hokazono, Hideki; Hida, Mariko; Sasaki, Takako; Yoshioka, Hidekatsu; Matsuo, Noritaka

2017-06-01

The multiple physiological effects of γ-aminobutyric acid (GABA) as a functional food component have been recently reported. We previously reported that GABA upregulated the expression of type I collagen in human dermal fibroblasts (HDFs), and that oral administration of GABA significantly increased skin elasticity. However, details of the regulatory mechanism still remain unknown. In this study, we further examined the effects of GABA on elastin synthesis and elastin fiber formation in HDFs. Real-time PCR indicated that GABA significantly increased the expression of tropoelastin transcript in a dose-dependent manner. Additionally, the expression of fibrillin-1, fibrillin-2, and fibulin-5/DANCE, but not lysyl oxidase and latent transforming factor-β-binding protein 4, were also significantly increased in HDFs. Finally, immunohistochemical analysis confirmed that treatment with GABA dramatically increased the formation of elastic fibers in HDFs. Taken together, our results showed that GABA improves skin elasticity in HDFs by upregulating elastin synthesis and elastin fiber formation.

Comparison of Effects on Gene Expression Activity of Low-Molecular-Weight Lychee Fruit Polyphenol (Oligonol®, Adenosine, and Minoxidil in Human Dermal Papilla Cells

Directory of Open Access Journals (Sweden)

Koji Wakame

2017-06-01

Full Text Available Background: Oligonol® (OLG is a functional food product and ingredient for cosmetics derived from a lychee fruit polyphenol. It has been reported to act on the skin as an anti-inflammatory and prevent UVB-induced skin damage. Aim: In this study, with the aim of exploring new functionalities of OLG on the scalp, we investigated the effect of OLG on human dermal papilla cells by comparing with adenosine and minoxidil at the genetic level. Method: OLG, adenosine, and minoxidil were applied to human dermal papilla cell lines for 24 h, after which VEGF, FGF-7, WNT5a, and WNT10a mRNA expressions were measured by real-time PCR analysis. Additionally, using DNA microarrays, we investigated the effect on 205 inflammation-related genes. Result: Consequently, in human dermal papilla cell lines, FGF-7 and WNT10a mRNA expression were observed in 100 µg/mL OLG-supplemented cells. The results of the DNA microarray analysis showed that 10 genes were suppressed by OLG. Conclusions: OLG may be expected to affect function of human dermal papilla cell by regulating the expression of genes related to cell proliferation and inflammation.

EVALUATING COMMERCIALLY AVAILABLE DERMAL ...

Science.gov (United States)

As the Human Exposure Program focuses on the exposure of children to pesticides, there are concerns about the effect, or perceived effect, of components of the sampling procedure on the health and well-being of the infant and the ability to collect pesticide residues. One concern involves the materials in wipes used to collect pesticide residues or other contact materials on the skin. In recent studies (e.g., National Human Exposure Assessment Survey; NHEXAS), isopropyl alcohol has been used as a solvent in conjunction with a cloth wipe to obtain samples from the hands of adults and children. Although isopropyl alcohol is generally considered innocuous, the use of commercially available products could eliminate concerns about exposure to alcohol. A few studies have evaluated the potential of commercially available baby wipes to collect personal exposure samples for metals research, but not for the area of pesticide research (Millson et al., 1994; Campbell et al., 1993; Lichtenwalner et al., 1993). Therefore, there is a need to evaluate the potential for using commercially available baby wipes for collecting pesticide samples from skin and other surfaces. Another concern involves establishing a convenient and safe method for assessing overall dermal exposure for children, especially for those in crawling stage. One route that the U .S. Environmental Protection Agency (EPA) would like to investigate is the use of cotton body suits (infant sleepers) as an indicator

Prevalence of camel tuberculosis and associated risk factors in ...

African Journals Online (AJOL)

A cross sectional abattoir based study was conducted from February 2014 to October, 2015 on camels slaughtered at Akaki municipality abattoir to determine the prevalence of Tuberculosis in camels and assess the association of risk factors with the prevalence of Tuberculosis in camels using single intra-dermal ...

Chitosan Dermal Substitute and Chitosan Skin Substitute Contribute to Accelerated Full-Thickness Wound Healing in Irradiated Rats

Directory of Open Access Journals (Sweden)

Abu Bakar Mohd Hilmi

2013-01-01

Full Text Available Wounds with full-thickness skin loss are commonly managed by skin grafting. In the absence of a graft, reepithelialization is imperfect and leads to increased scar formation. Biomaterials can alter wound healing so that it produces more regenerative tissue and fewer scars. This current study use the new chitosan based biomaterial in full-thickness wound with impaired healing on rat model. Wounds were evaluated after being treated with a chitosan dermal substitute, a chitosan skin substitute, or duoderm CGF. Wounds treated with the chitosan skin substitute showed the most re-epithelialization (33.2 ± 2.8%, longest epithelial tongue (1.62 ± 0.13 mm, and shortest migratory tongue distance (7.11 ± 0.25 mm. The scar size of wounds treated with the chitosan dermal substitute (0.13 ± 0.02 cm and chitosan skin substitute (0.16 ± 0.05 cm were significantly decreased (P<0.05 compared with duoderm (0.45 ± 0.11 cm. Human leukocyte antigen (HLA expression on days 7, 14, and 21 revealed the presence of human hair follicle stem cells and fibroblasts that were incorporated into and surviving in the irradiated wound. We have proven that a chitosan dermal substitute and chitosan skin substitute are suitable for wound healing in full-thickness wounds that are impaired due to radiation.

Potential Dermal Exposure in greenhouses for manual sprayers: Analysis of the mix/load, application and re-entry stages

Energy Technology Data Exchange (ETDEWEB)

Ramos, Laura M.; Querejeta, Giselle A.; Flores, Andrea P.; Hughes, Enrique A.; Zalts, Anita [Instituto de Ciencias, Universidad Nacional de General Sarmiento (UNGS), J. M. Gutierrez 1150, (B1613GSX) Los Polvorines, Prov. de Buenos Aires (Argentina); Montserrat, Javier M., E-mail: jmontser@ungs.edu.ar [Instituto de Ciencias, Universidad Nacional de General Sarmiento (UNGS), J. M. Gutierrez 1150, (B1613GSX) Los Polvorines, Prov. de Buenos Aires (Argentina); Instituto de Investigaciones en Ingenieria Genetica y Biologia Molecular (CONICET), Vuelta de Obligado 2490, 2o piso, Buenos Aires (Argentina)

2010-09-01

An evaluation of the Potential Dermal Exposure for the mix/load, application and re-entry stages, associated with procymidone and deltamethrin usage, was carried out for tomatoes grown in greenhouses of small production units in Argentina. Eight experiments were done with four different operators, under typical field conditions with a lever operated backpack sprayer. The methodology applied was based on the Whole Body Dosimetry technique, evaluating a set of different data for the mix and load, application and re-entry operations. These results indicated that the Potential Dermal Exposure of the application step was (38 {+-} 17) mL h{sup -1} with the highest proportion on torso, head and arms. When the three stages were compared, re-entry was found to contribute least towards the total Potential Dermal Exposure; meanwhile in all cases, except one, the mix/load operation was the stage with highest exposure. The Margin of Safety for each different operation was also calculated and the proportion of pesticide drift from the greenhouse to the environment is presented. These results emphasize the importance of improving the personal protection measures in the mix and load stage, an operation that is not usually associated with high-risk in small production units.

Potential Dermal Exposure in greenhouses for manual sprayers: Analysis of the mix/load, application and re-entry stages

International Nuclear Information System (INIS)

Ramos, Laura M.; Querejeta, Giselle A.; Flores, Andrea P.; Hughes, Enrique A.; Zalts, Anita; Montserrat, Javier M.

2010-01-01

An evaluation of the Potential Dermal Exposure for the mix/load, application and re-entry stages, associated with procymidone and deltamethrin usage, was carried out for tomatoes grown in greenhouses of small production units in Argentina. Eight experiments were done with four different operators, under typical field conditions with a lever operated backpack sprayer. The methodology applied was based on the Whole Body Dosimetry technique, evaluating a set of different data for the mix and load, application and re-entry operations. These results indicated that the Potential Dermal Exposure of the application step was (38 ± 17) mL h -1 with the highest proportion on torso, head and arms. When the three stages were compared, re-entry was found to contribute least towards the total Potential Dermal Exposure; meanwhile in all cases, except one, the mix/load operation was the stage with highest exposure. The Margin of Safety for each different operation was also calculated and the proportion of pesticide drift from the greenhouse to the environment is presented. These results emphasize the importance of improving the personal protection measures in the mix and load stage, an operation that is not usually associated with high-risk in small production units.

3-Deoxysappanchalcone Promotes Proliferation of Human Hair Follicle Dermal Papilla Cells and Hair Growth in C57BL/6 Mice by Modulating WNT/β-Catenin and STAT Signaling

Science.gov (United States)

Kim, Young Eun; Choi, Hyung Chul; Lee, In-Chul; Yuk, Dong Yeon; Lee, Hyosung; Choi, Bu Young

2016-01-01

3-Deoxysappanchalcone (3-DSC) has been reported to possess anti-allergic, antiviral, anti-inflammatory and antioxidant activities. In the present study, we investigated the effects of 3-DSC on the proliferation of human hair follicle dermal papilla cells (HDPCs) and mouse hair growth in vivo. A real-time cell analyzer system, luciferase assay, Western blot and real-time polymerase chain reaction (PCR) were employed to measure the biochemical changes occurring in HDPCs in response to 3-DSC treatment. The effect of 3-DSC on hair growth in C57BL/6 mice was also examined. 3-DSC promoted the proliferation of HDPCs, similar to Tofacitinib, an inhibitor of janus-activated kinase (JAK). 3-DSC promoted phosphorylation of β-catenin and transcriptional activation of the T-cell factor. In addition, 3-DSC potentiated interleukin-6 (IL-6)-induced phosphorylation and subsequent transactivation of signal transducer and activator of transcription-3 (STAT3), thereby increasing the expression of cyclin-dependent kinase-4 (Cdk4), fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF). On the contrary, 3-DSC attenuated STAT6 mRNA expression and IL4-induced STAT6 phosphorylation in HDPCs. Finally, we observed that topical application of 3-DSC promoted the anagen phase of hair growth in C57BL/6 mice. 3-DSC stimulates hair growth possibly by inducing proliferation of follicular dermal papilla cells via modulation of WNT/β-catenin and STAT signaling. PMID:27795451

Bryostatin and its synthetic analog, picolog rescue dermal fibroblasts from prolonged stress and contribute to survival and rejuvenation of human skin equivalents.

Science.gov (United States)

Khan, Tapan K; Wender, Paul A; Alkon, Daniel L

2018-02-01

Skin health is associated with the day-to-day activity of fibroblasts. The primary function of fibroblasts is to synthesize structural proteins, such as collagen, extracellular matrix proteins, and other proteins that support the structural integrity of the skin and are associated with younger, firmer, and more elastic skin that is better able to resist and recover from injury. At sub-nanomolar concentrations (0.03-0.3 nM), bryostatin-1 and its synthetic analog, picolog (0.1-10 nM) sustained the survival and activation of human dermal fibroblasts cultured under the stressful condition of prolonged serum deprivation. Bryostatin-1 treatment stabilized human skin equivalents (HSEs), a bioengineered combination of primary human skin cells (keratinocytes and dermal fibroblasts) on an extracellular matrix composed of mainly collagen. Fibroblasts activated by bryostatin-1 protected the structural integrity of HSEs. Bryostatin-1 and picolog prolonged activation of Erk in fibroblasts to promote cell survival. Chronic stress promotes the progression of apoptosis. Dermal fibroblasts constitutively express all components of Fas associated apoptosis, including caspase-8, an initiator enzyme of apoptosis. Prolong bryostatin-1 treatment reduced apoptosis by decreasing caspase-8 and protected dermal fibroblasts. Our data suggest that bryostatin-1 and picolog could be useful in anti-aging skincare, and could have applications in tissue engineering and regenerative medicine. © 2017 Wiley Periodicals, Inc.

Carbon nanotubes (CNTs) based advanced dermal therapeutics: current trends and future potential.

Science.gov (United States)

Kuche, Kaushik; Maheshwari, Rahul; Tambe, Vishakha; Mak, Kit-Kay; Jogi, Hardi; Raval, Nidhi; Pichika, Mallikarjuna Rao; Kumar Tekade, Rakesh

2018-05-17

The search for effective and non-invasive delivery modules to transport therapeutic molecules across skin has led to the discovery of a number of nanocarriers (viz.: liposomes, ethosomes, dendrimers, etc.) in the last few decades. However, available literature suggests that these delivery modules face several issues including poor stability, low encapsulation efficiency, and scale-up hurdles. Recently, carbon nanotubes (CNTs) emerged as a versatile tool to deliver therapeutics across skin. Superior stability, high loading capacity, well-developed synthesis protocol as well as ease of scale-up are some of the reason for growing interest in CNTs. CNTs have a unique physical architecture and a large surface area with unique surface chemistry that can be tailored for vivid biomedical applications. CNTs have been thus largely engaged in the development of transdermal systems such as tuneable hydrogels, programmable nonporous membranes, electroresponsive skin modalities, protein channel mimetic platforms, reverse iontophoresis, microneedles, and dermal buckypapers. In addition, CNTs were also employed in the development of RNA interference (RNAi) based therapeutics for correcting defective dermal genes. This review expounds the state-of-art synthesis methodologies, skin penetration mechanism, drug liberation profile, loading potential, characterization techniques, and transdermal applications along with a summary on patent/regulatory status and future scope of CNT based skin therapeutics.

Suppressive effects of primed eosinophils on single epicutaneous sensitization through regulation of dermal dendritic cells.

Science.gov (United States)

Lin, Jing-Yi; Ta, Yng-Cun; Liu, I-Lin; Chen, Hsi-Wen; Wang, Li-Fang

2016-07-01

Eosinophils are multifunctional innate immune cells involved in many aspects of innate and adaptive immunity. Epicutaneous sensitization with protein allergen is an important sensitization route for atopic dermatitis. In this study, using a murine single protein-patch model, we show that eosinophils of a primed status accumulate in draining lymph nodes following single epicutaneous sensitization. Further, depletion of eosinophils results in enhancement of the induced Th1/Th2 immune responses, whereas IL-5-induced hypereosinophilia suppresses these responses. Mechanistically, primed eosinophils cause a reduction in the numbers and activation status of dermal dendritic cells in draining lymph nodes. Collectively, these results demonstrate that primed eosinophils exert suppressive effects on single epicutaneous sensitization through regulation of dermal dendritic cells. Thus, these findings highlight the critical roles of eosinophils in the pathogenesis of atopic dermatitis with important clinical implications for the prevention of allergen sensitization. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Binding affinity and decontamination of dermal decontamination gel to model chemical warfare agent simulants.

Science.gov (United States)

Cao, Yachao; Elmahdy, Akram; Zhu, Hanjiang; Hui, Xiaoying; Maibach, Howard

2018-05-01

Six chemical warfare agent simulants (trimethyl phosphate, dimethyl adipate, 2-chloroethyl methyl sulfide, diethyl adipate, chloroethyl phenyl sulfide and diethyl sebacate) were studied in in vitro human skin to explore relationship between dermal penetration/absorption and the mechanisms of simulant partitioning between stratum corneum (SC) and water as well as between dermal decontamination gel (DDGel) and water. Both binding affinity to and decontamination of simulants using DDGel were studied. Partition coefficients of six simulants between SC and water (Log P SC/w ) and between DDGel and water (Log P DDGel/w ) were determined. Results showed that DDGel has a similar or higher binding affinity to each simulant compared to SC. The relationship between Log P octanol/water and Log P SC/w as well as between Log P octanol/water and Log P DDGel/w demonstrated that partition coefficient of simulants correlated to their lipophilicity or hydrophilicity. Decontamination efficiency results with DDGel for these simulants were consistent with binding affinity results. Amounts of percentage dose of chemicals in DDGel of trimethyl phosphate, dimethyl adipate, 2-chloroethyl methyl sulfide, diethyl adipate, chloroethyl phenyl sulfide and diethyl sebacate were determined to be 61.15, 85.67, 75.91, 53.53, 89.89 and 76.58, with corresponding amounts absorbed in skin of 0.96, 0.65, 1.68, 0.72, 0.57 and 1.38, respectively. In vitro skin decontamination experiments coupled with a dermal absorption study demonstrated that DDGel can efficiently remove chemicals from skin surface, back-extract from the SC, and significantly reduced chemical penetration into skin or systemic absorption for all six simulants tested. Therefore, DDGel offers a great potential as a NextGen skin Decon platform technology for both military and civilian use. Copyright © 2018 John Wiley & Sons, Ltd.

Squarticles as a lipid nanocarrier for delivering diphencyprone and minoxidil to hair follicles and human dermal papilla cells.

Science.gov (United States)

Aljuffali, Ibrahim A; Sung, Calvin T; Shen, Feng-Ming; Huang, Chi-Ting; Fang, Jia-You

2014-01-01

Delivery of diphencyprone (DPCP) and minoxidil to hair follicles and related cells is important in the treatment of alopecia. Here we report the development of "squarticles," nanoparticles formed from sebum-derived lipids such as squalene and fatty esters, for use in achieving targeted drug delivery to the follicles. Two different nanosystems, nanostructured lipid carriers (NLC) and nanoemulsions (NE), were prepared. The physicochemical properties of squarticles, including size, zeta potential, drug encapsulation efficiency, and drug release, were examined. Squarticles were compared to a free control solution with respect to skin absorption, follicular accumulation, and dermal papilla cell targeting. The particle size of the NLC type was 177 nm; that of the NE type was 194 nm. Approximately 80% of DPCP and 60% of minoxidil were entrapped into squarticles. An improved drug deposition in the skin was observed in the in vitro absorption test. Compared to the free control, the squarticles reduced minoxidil penetration through the skin. This may indicate a minimized absorption into systemic circulation. Follicular uptake by squarticles was 2- and 7-fold higher for DPCP and minoxidil respectively compared to the free control. Fluorescence and confocal images of the skin confirmed a great accumulation of squarticles in the follicles and the deeper skin strata. Vascular endothelial growth factor expression in dermal papilla cells was significantly upregulated after the loading of minoxidil into the squarticles. In vitro papilla cell viability and in vivo skin irritancy tests in nude mice suggested a good tolerability of squarticles to skin. Squarticles provide a promising nanocarrier for topical delivery of DPCP and minoxidil.

Clotting of mammalian fibrinogens by papain: A re-examination

OpenAIRE

Doolittle, RF

2014-01-01

© 2014 American Chemical Society. Papain has long been known to cause the gelation of mammalian fibrinogens. It has also been reported that papain-fibrin is insoluble in dispersing solvents like strong urea or sodium bromide solutions, similar to what is observed with thrombin-generated clots in the presence of factor XIIIa and calcium. In those old studies, both the gelation and subsequent clot stabilization were attributed to papain, although the possibility that the second step might be du...

Silk sericin/polyacrylamide in situ forming hydrogels for dermal reconstruction.

Science.gov (United States)

Kundu, Banani; Kundu, Subhas C

2012-10-01

In situ forming tissue sealants are advantageous due to ease in application, complete coverage of defect site and assured comfort levels to patients. The interconnected three-dimensional hydrophilic networks perfectly manage typical dermal wounds by suitably scaffolding skin fibroblast, diffusing the nutrients, therapeutics and exudates while still maintaining an adequately moist environment. We evaluate the cell homing ability of semi-interpenetrating non-mulberry tropical tasar silk sericin/polyacrylamide hydrophilic network with a keen understanding of its network characteristics and correlation of protein concentration with the performance as cell scaffold. Interconnectivity of porous networks observed through scanning electron micrograph revealed pore sizes ranging from 23 to 52 μm. The enhanced β-sheet content with the increasing sericin concentration in far red spectroscopy study supported their corresponding improved compressive strength. These semi-interpenetrating networks were found to possess a maximum fluid uptake of 112% of its weight, hence preventing the accumulation of exudates at the wound area. The present systems appear to possess characteristics like rapid gelation (~5min) at 37 °C, 98% porosity enabling the migration of fibroblasts during healing (observed through confocal and scanning electron micrographs), cell adhesion together with the absence of any cyto-toxic effect suggesting its potential as in situ tissue sealants. The compressive strength up to 61 kPa ensured ease in handling even when wet. The results prove the suitability to use non-mulberry tasar cocoon silk sericin/polyacrylamide semi-interpenetrating network as a reconstructive dermal sealant. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mutations in X-linked PORCN, a putative regulator of Wnt signaling, cause focal dermal hypoplasia

Science.gov (United States)

Focal dermal hypoplasia is an X-linked dominant disorder characterized by patchy hypoplastic skin and digital, ocular, and dental malformations. We used array comparative genomic hybridization to identify a 219-kb deletion in Xp11.23 in two affected females. We sequenced genes in this region and fou...

Soft tissue augmentation - Use of hyaluronic acid as dermal filler

Directory of Open Access Journals (Sweden)

Vedamurthy Maya

2004-11-01

Full Text Available Soft tissue augmentation has revolutionized the treatment of the aging face. It is a technique in which a substance is injected under the skin. The concept of utilizing materials for soft tissue augmentation actually began around 1950 with the use of fluid silicone. Today we have a large armamentarium of implant materials to delay the tell tale signs of aging. Filling has replaced conventional surgery in facial rejuvenation. In this article, the emphasis will be on hyaluronic acid as this substance is easily available in India and ranks among the most widely used dermal fillers.

Soft tissue augmentation - Use of hyaluronic acid as dermal filler

Directory of Open Access Journals (Sweden)

Vedamurthy Maya

2004-01-01

Full Text Available Soft tissue augmentation has revolutionized the treatment of the aging face. It is a technique in which a substance is injected under the skin. The concept of utilizing materials for soft tissue augmentation actually began around 1950 with the use of fluid silicone. Today we have a large armamentarium of implant materials to delay the tell tale signs of aging. Filling has replaced conventional surgery in facial rejuvenation. In this article, the emphasis will be on hyaluronic acid as this substance is easily available in India and ranks among the most widely used dermal fillers.

Linking a dermal permeation and an inhalation model to a simple pharmacokinetic model to study airborne exposure to di(n-butyl) phthalate

OpenAIRE

Lorber, M.; Weschler, C.J.; Morrison, G.; Bekö, G.; Gong, M.; Koch, H.M.; Salthammer, T.; Schripp, T.; Toftum, J.; Clausen, G.

2017-01-01

Six males clad only in shorts were exposed to high levels of airborne di(n-butyl) phthalate (DnBP) and diethyl phthalate (DEP) in chamber experiments conducted in 2014. In two 6 h sessions, the subjects were exposed only dermally while breathing clean air from a hood, and both dermally and via inhalation when exposed without a hood. Full urine samples were taken before, during, and for 48 h after leaving the chamber and measured for key DnBP and DEP metabolites. The data clearly demonstrated ...

Multiple helminth infection of the skin causes lymphocyte hypo-responsiveness mediated by Th2 conditioning of dermal myeloid cells.

Directory of Open Access Journals (Sweden)

Peter C Cook

2011-03-01

Full Text Available Infection of the mammalian host by schistosome larvae occurs via the skin, although nothing is known about the development of immune responses to multiple exposures of schistosome larvae, and/or their excretory/secretory (E/S products. Here, we show that multiple (4x exposures, prior to the onset of egg laying by adult worms, modulate the skin immune response and induce CD4(+ cell hypo-responsiveness in the draining lymph node, and even modulate the formation of hepatic egg-induced granulomas. Compared to mice exposed to a single infection (1x, dermal cells from multiply infected mice (4x, were less able to support lymph node cell proliferation. Analysis of dermal cells showed that the most abundant in 4x mice were eosinophils (F4/80(+MHC-II(-, but they did not impact the ability of antigen presenting cells (APC to support lymphocyte proliferation to parasite antigen in vitro. However, two other cell populations from the dermal site of infection appear to have a critical role. The first comprises arginase-1(+, Ym-1(+ alternatively activated macrophage-like cells, and the second are functionally compromised MHC-II(hi cells. Through the administration of exogenous IL-12 to multiply infected mice, we show that these suppressive myeloid cell phenotypes form as a consequence of events in the skin, most notably an enrichment of IL-4 and IL-13, likely resulting from an influx of RELMα-expressing eosinophils. We further illustrate that the development of these suppressive dermal cells is dependent upon IL-4Rα signalling. The development of immune hypo-responsiveness to schistosome larvae and their effect on the subsequent response to the immunopathogenic egg is important in appreciating how immune responses to helminth infections are modulated by repeated exposure to the infective early stages of development.

Possible role of ginsenoside Rb1 in skin wound healing via regulating senescent skin dermal fibroblast.

Science.gov (United States)

Hou, Jingang; Kim, Sunchang

2018-05-05

Cellular senescence suppresses cancer by inducing irreversible cell growth arrest. Nevertheless, senescent cells is proposed as causal link with aging and aging-related pathologies. The physiological beneficial functions of senescent cells are still of paucity. Here we show that senescent human dermal fibroblast accelerates keratinocytes scratch wound healing and stimulates differentiation of fibroblast. Using oxidative stress (100 μM H 2 O 2 exposure for 1 h) induction, we successfully triggered fibroblast senescence and developed senescence associated secretory phenotype (SASP). The induction of SASP was regulated by p38MAPK/MSK2/NF-κB pathway. Interestingly, inhibition of p38MAPK activation only partially suppressed SASP. However, SASP was significantly inhibited by SB747651A, a specific MSK inhibitor. Additionally, we demonstrate that SASP stimulates migration of keratinocytes and myofibroblast transition of fibroblast, through fold-increased secretion of growth factors, platelet-derived growth factor AA (PDGF-AA) and AB (PDGF-AB), transforming growth factor beta 1 (TGF-β1) and beta 2 (TGF-β2), vascular endothelial growth factor A (VEGF-A) and D (VEGF-D), vascular endothelial growth factor receptor 2 (VEGFR2) and 3 (VEGFR3). Importantly, we also confirmed ginsenoside Rb1 promoted SASP-mediated healing process via p38MAPK/MSK2/NF-κB pathway. The results pointed to senescent fibroblast as a potential mechanism of wound healing control in human skin. Further, it provided a candidate targeted for wound therapy. Copyright © 2018 Elsevier Inc. All rights reserved.

Investigation of the effect of hydration on dermal collagen in ex vivo human skin tissue using second harmonic generation microscopy

Science.gov (United States)

Samatham, Ravikant; Wang, Nicholas K.; Jacques, Steven L.

2016-02-01

Effect of hydration on the dermal collagen structure in human skin was investigated using second harmonic generation microscopy. Dog ears from the Mohs micrographic surgery department were procured for the study. Skin samples with subject aged between 58-90 years old were used in the study. Three dimensional Multiphoton (Two-photon and backward SHG) control data was acquired from the skin samples. After the control measurement, the skin tissue was either soaked in deionized water for 2 hours (Hydration) or kept at room temperature for 2 hours (Desiccation), and SHG data was acquired. The data was normalized for changes in laser power and detector gain. The collagen signal per unit volume from the dermis was calculated. The desiccated skin tissue gave higher backward SHG compared to respective control tissue, while hydration sample gave a lower backward SHG. The collagen signal decreased with increase in hydration of the dermal collagen. Hydration affected the packing of the collagen fibrils causing a change in the backward SHG signal. In this study, the use of multiphoton microscopy to study the effect of hydration on dermal structure was demonstrated in ex vivo tissue.

Composite synthetic hydroxyapatite 30%, in two physical states, as dermal filler

Directory of Open Access Journals (Sweden)

Rodrigo Viana Sepúlveda

2013-08-01

Full Text Available The aim of this study was to evaluate the response to the implantation of synthetic hydroxyapatite 30% (HAP-91® in different physical states as dermal filler. Eighteen New Zealand rabbits were used, distributed randomly into two equal groups and then divided into three groups according to the postoperative period at 8, 21 and 49 days. One mL of HAP-91®, fluid and viscous, was implanted in the subcutaneous tissue, 1 cm proximal to the cranial crest of the right scapula. The thickness of the skin was measured before and after implantation and for the following 15 days. Pain sensitivity assessment was conducted, assigning the following scores: 0 - when the animal allowed the touch of the implant area and expressed no signs of pain; 1 - when the animal allowed the touch, but pain reaction occurred, like increase of the respiratory rate or attempt to escape; 2 - when the animal did not allow the touch to the implanted area. At 8, 21 and 49 days, biopsy of the implanted area was performed. No difference was observed between the thickness of the skin (p>0.05 and all animals received a score 0 for soreness. Histological analysis did not reveal any obvious inflammatory process, showing a predominance of mononuclear cells in samples of eight days and tissue organization around the biomaterial with a tendency to encapsulation. The results indicate that HAP-91®, both viscous and fluid, is biocompatible and suitable for dermal filling.

Synthetic inhibitors of matrix metalloproteinases prevent sulfur mustard-induced epidermal-dermal separation in human skin pieces

NARCIS (Netherlands)

Mol, M.A.E.; Alblas, S.W.; Hammer, A.; Benschop, H.P.

2000-01-01

Degradation of proteins of the basement membrane zone (BMZ) in the skin depends on the activity of proteolytic enzymes, particularly those belonging to the group of matrix metalloproteinases (MMPs). In the present study we have investigated the contribution of these enzymes to the epidermal-dermal

Surgical Implications of Asymmetric Distribution of Dermal Collagen and Elastic Fibres in Two Orientations of Skin Samples from Extremities

Directory of Open Access Journals (Sweden)

Naveen Kumar

2014-01-01

Full Text Available Background. Clinically, scar related complications are observed to be dissimilar in different regions of the body. Unequal distribution of dermal collagen and elastic fibres in different orientations could be one of the multifocal causes of scar related complications, for which this evaluating study has been taken up. Materials and Method. 300 skin samples collected in horizontal and vertical orientations were studied histomorphometrically. This study involved image analysis of specially stained histological section using tissue-quant software. The outcome result was termed as quantitative fraction. From the result, various ratio values were also calculated for the ratio analysis. Results. The differences in the quantitative fraction of dermal elastic content between 2 directions were statistically significant at joint areas (shoulder joint, wrist, and ankle (P<0.001 but for collagen, significant difference was observed at shoulder joint and wrist only. Dermis of the forearm and thigh did not show any differences in their collagen content, but for elastic, thigh did show a significant difference while forearm had no change between 2 directions. Conclusion. Analysis of unequal content of dermal element in two directions under the perspective of wound healing consequences is subjective depending upon the anatomical position and functional status of the areas.

Atypical Post Kala Azar Dermal Leishmaniasis with “Muzzle Area” Swelling

Science.gov (United States)

Arora, Sandeep; Bal, Arvinder Singh; Baveja, Sukriti; Sood, Aradhana; Rathi, Khushi Ram; Patil, Pradeep

2015-01-01

A 50-year-old male presented with recurrent swelling of the muzzle area of the face with history of low-grade intermittent fever of 3 year duration managed variously with antibiotics, systemic steroids, and antituberculous therapy. Skin biopsy revealed a granulomatous infiltration negative for acid-fast bacilli and leishmania donovan bodies. Immunochromatography test for rK 39 antigen and polymerase chain reaction for leishmania was positive. He was diagnosed as a case of post kala azar dermal leishmaniasis, managed with injection sodium stibogluconate and followed-up thereafter. PMID:25657406

Large pore dermal microdialysis and liquid chromatography-tandem mass spectroscopy shotgun proteomic analysis: a feasibility study

DEFF Research Database (Denmark)

Petersen, Lars J.; Sorensen, Mette A.; Codrea, Marius C.

2013-01-01

Background/AimsThe purpose of the present pilot study was to investigate the feasibility of combining large pore dermal microdialysis with shotgun proteomic analysis in human skin. MethodsDialysate was recovered from human skin by 2000 kDa microdialysis membranes from one subject at three different...

Fine needle aspiration cytology of dermal cylindroma

Directory of Open Access Journals (Sweden)

Parikshaa Gupta

2014-01-01

Full Text Available In this paper, we have described fine needle aspiration cytology (FNAC of a rare case of dermal cylindroma. A 40-year-old female presented with a lateral mid-cervical swelling fixed to the skin. FNAC smears showed multiple clusters of small, round to oval cells with hyperchromatic nuclei, inconspicuous nucleoli and scant cytoplasm. In addition, the background showed deposits of basement membrane type material. This was dark magenta colored pinkish globular material. The globules were occasionally surrounded by the basal type of cells. Occasional cells with elongated nuclei were also noted. Cytological diagnosis of skin adnexal tumor possibly cylindroma was offered. Subsequent histopathology of the swelling showed sheets and clusters of cells in a jigsaw puzzle-like fashion. Deposition of abundant basement membrane-like material was noted in between the tumor cells. A diagnosis of cylindorma was offered. FNAC along with the subcutaneous location of the tumor and absence of primary salivary gland tumor may help to diagnose such rare case.

Arctiin blocks hydrogen peroxide-induced senescence and cell death though microRNA expression changes in human dermal papilla cells

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Seunghee Bae

2014-01-01

Full Text Available BACKGROUND: Accumulating evidence indicates that reactive oxygen species (ROS are an important etiological factor for the induction of dermal papilla cell senescence and hair loss, which is also known alopecia. Arctiin is an active lignin isolated from Arctium lappa and has anti-inflammation, anti-microbial, and anti-carcinogenic effects. In the present study, we found that arctiin exerts anti-oxidative effects on human hair dermal papilla cells (HHDPCs. RESULTS: To better understand the mechanism, we analyzed the level of hydrogen peroxide (H2O2-induced cytotoxicity, cell death, ROS production and senescence after arctiin pretreatment of HHDPCs. The results showed that arctiin pretreatment significantly inhibited the H2O2-induced reduction in cell viability. Moreover, H2O2-induced sub-G1 phase accumulation and G2 cell cycle arrest were also downregulated by arctiin pretreatment. Interestingly, the increase in intracellular ROS mediated by H2O2 was drastically decreased in HHDPCs cultured in the presence of arctiin. This effect was confirmed by senescence associated-beta galactosidase (SA-β-gal assay results; we found that arctiin pretreatment impaired H2O2-induced senescence in HHDPCs. Using microRNA (miRNA microarray and bioinformatic analysis, we showed that this anti-oxidative effect of arctiin in HHDPCs was related with mitogen-activated protein kinase (MAPK and Wnt signaling pathways. CONCLUSIONS: Taken together, our data suggest that arctiin has a protective effect on ROS-induced cell dysfunction in HHDPCs and may therefore be useful for alopecia prevention and treatment strategies.

Effect of microemulsions on cell viability of human dermal fibroblasts

Science.gov (United States)

Li, Juyi; Mironava, Tatsiana; Simon, Marcia; Rafailovich, Miriam; Garti, Nissim

Microemulsions are optically clear, thermostable and isotropic mixture consisting of water, oil and surfactants. Their advantages of ease preparation, spontaneous formation, long-term stability and enhanced solubility of bioactive materials make them great potentials as vehicles in food and pharmaceutical applications. In this study, comparative in vitro cytotoxicity tests were performed to select a best formulation of microemulsion with the least toxicity for human dermal fibroblasts. Three different kinds of oils and six different kinds of surfactants were used to form microemulsions by different ratios. The effect of oil type and surfactant type as well as their proportions on cell proliferation and viability were tested.

A unique dermal dendritic cell subset that skews the immune response toward Th2.

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Ryuichi Murakami

Full Text Available Dendritic cell (DC subsets in the skin and draining lymph nodes (LNs are likely to elicit distinct immune response types. In skin and skin-draining LNs, a dermal DC subset expressing macrophage galactose-type C-type lectin 2 (MGL2/CD301b was found distinct from migratory Langerhans cells (LCs or CD103(+ dermal DCs (dDCs. Lower expression levels of Th1-promoting and/or cross-presentation-related molecules were suggested by the transcriptome analysis and verified by the quantitative real-time PCR analysis in MGL2(+ dDCs than in CD103(+ dDCs. Transfer of MGL2(+ dDCs but not CD103(+ dDCs from FITC-sensitized mice induced a Th2-type immune response in vivo in a model of contact hypersensitivity. Targeting MGL2(+ dDCs with a rat monoclonal antibody against MGL2 efficiently induced a humoral immune response with Th2-type properties, as determined by the antibody subclass. We propose that the properties of MGL2(+ dDCs, are complementary to those of CD103(+ dDCs and skew the immune response toward a Th2-type response.

Preclinical pilot study monitoring topical drug penetration and dermal bioavailability of a peptidase inhibitor from different galenic formulations into pig dermis, using cutaneous microdialysis.

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Quist, S R; Heimburg, A; Bank, U; Mahnkopf, D; Koch, G; Gollnick, H; Täger, M; Ansorge, S

2017-08-01

Cutaneous microdialysis (CM) is an ex vivo technique that allows study of tissue chemistry, including bioavailability of actual tissue concentration of unbound drug in the interstitial fluid of the body. To test the penetration and dermal bioavailability of galenic formulations of the small-molecule IP10.C8, a dual-protease inhibitor of the dipeptidyl peptidase and aminopeptidase families. Using CM, we tested the penetration and dermal bioavailability of IP10.C8 into the dermis and subcutis of pigs, and determined the tissue concentration of IP10.C8 enzymatically, using an enzyme activity assay (substrate Gly-Pro-pNA) and high performance liquid chromatography. Dermal bioavailability was enhanced by using microemulsion or the addition of the penetration enhancer oleic acid to a hydroxyethylcellulose (HEC) gel formulation. Dermal bioavailability was also enhanced when galenic formulations were prepared with higher pH (7.5 vs. 6.5) or higher drug concentration (5% vs. 1%) in HEC gel. It seems possible, using CM for topical skin penetration testing in anaesthetized domestic pigs, to test the bioavailability of newly designed drugs. However, the experimental time is limited due to the anaesthesia, and is dependent on drug recovery. Validation of this technique for routine use is challenging, and more experiments are needed to validate this preclinical set-up. © 2017 British Association of Dermatologists.

Post-kala-azar dermal leishmaniasis associated with AIDS

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Bittencourt Achiléa

2002-01-01

Full Text Available Post-kala-azar dermal leishmaniasis (PKDL is rarely reported in South America. In spite of the fact that there are many reports about the association of visceral leishmaniasis and AIDS, PKDL is very uncommon in HIV-positive patients, and so far only four cases have been documented in the literature. We present another case with unusual clinicopathological aspects. The patient, a 28-year-old male, from Salvador, Bahia (an endemic area presented with clinical manifestations of visceral leishmaniasis three years after the diagnosis of AIDS. During treatment for visceral leishmaniasis he developed disseminated miliary papules. Microscopically, the skin biopsy showed a "saw-tooth" pattern with a lichenoid mononuclear infiltrate simulating lichen planus. The histopathological diagnosis was achieved through the finding of amastigotes. The authors discuss the clinicopathological aspects of this case based on a review of the specific literature.

Post-kala-azar dermal leishmaniasis associated with AIDS

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Bittencourt Achiléa

2003-01-01

Full Text Available Post-kala-azar dermal leishmaniasis (PKDL is rarely reported in South America. In spite of the fact that there are many reports about the association of visceral leishmaniasis and AIDS, PKDL is very uncommon in HIV-positive patients, and so far only four cases have been documented in the literature. We present another case with unusual clinicopathological aspects. The patient, a 28-year-old male, from Salvador, Bahia (an endemic area presented with clinical manifestations of visceral leishmaniasis three years after the diagnosis of AIDS. During treatment for visceral leishmaniasis he developed disseminated miliary papules. Microscopically, the skin biopsy showed a "saw-tooth" pattern with a lichenoid mononuclear infiltrate simulating lichen planus. The histopathological diagnosis was achieved through the finding of amastigotes. The authors discuss the clinicopathological aspects of this case based on a review of the specific literature.

Lemongrass (Cymbopogon flexuosus) essential oil demonstrated anti-inflammatory effect in pre-inflamed human dermal fibroblasts.

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Han, Xuesheng; Parker, Tory L

2017-06-01

Lemongrass ( Cymbopogon flexuosus ) essential oil (LEO), which has citral as its main component, has exhibited anti-inflammatory effect in both animal and human cells. In this study, we evaluated the anti-inflammatory activity of a commercially available LEO in pre-inflamed human dermal fibroblasts. We first studied the impact of LEO on 17 protein biomarkers that are critically associated with inflammation and tissue remodeling. LEO significantly inhibited production of the inflammatory biomarkers vascular cell adhesion molecule 1 (VCAM-1), interferon gamma-induced protein 10 (IP-10), interferon-inducible T-cell alpha chemoattractant (I-TAC), and monokine induced by gamma interferon (MIG); decreased levels of the tissue remodeling biomarkers collagen-I and III, epidermal growth factor receptor (EGFR), and plasminogen activator inhibitor (PAI-1); and inhibited the immunomodulatory biomarker macrophage colony-stimulating factor (M-CSF). Furthermore, we studied the impact of LEO on genome-wide gene expression profiles. LEO significantly modulated global gene expression and robustly impacted signaling pathways, many of which are critical for inflammation and tissue remodeling processes. This study provides the first evidence of the anti-inflammatory activity of LEO in human skin cells and indicates that it is a good therapeutic candidate for treating inflammatory conditions of the skin.

VEGF induces proliferation of human hair follicle dermal papilla cells through VEGFR-2-mediated activation of ERK

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Li, Wei; Man, Xiao-Yong; Li, Chun-Ming; Chen, Jia-Qi; Zhou, Jiong; Cai, Sui-Qing; Lu, Zhong-Fa; Zheng, Min

2012-01-01

Vascular endothelial growth factor (VEGF) is one of the strongest regulators of physiological and pathological angiogenesis. VEGF receptor 2 (VEGFR-2), the primary receptor for VEGF, is thought to mediate major functional effects of VEGF. Previously, we have localized both VEGF and VEGFR-2 in human hair follicles. In this study, we further defined the expression and roles of VEGFR-2 on human hair follicle dermal papilla (DP) cells. The expression of VEGFR-2 on DP cells was examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis separately, and localization of VEGFR-2 was defined by immunofluorescence. The effect of VEGF on DP cells was analyzed by MTT assays and specific inhibitors. Finally, the role of VEGF involved in the signaling pathways was investigated by Western blot. RT-PCR and Western blot analysis demonstrated the expression of VEGFR-2 on DP cells. Immunostaining for VEGFR-2 showed strong signal on cultured human DP cells in vitro. Exogenous VEGF 165 stimulated proliferation of DP cells in a dose-dependent manner. Furthermore, this stimulation was blocked by a VEGFR-2 neutralizing antibody (MAB3571) and an ERK inhibitor (PD98059). VEGF 165 -induced phosphorylation of ERK1/2 was abolished by MAB3571 and PD98059, while the phosphorylation of p38, JNK and AKT were not changed by VEGF 165 . Taken together, VEGFR-2 is expressed on primary human hair follicle DP cells and VEGF induces proliferation of DP cells through VEGFR-2/ERK pathway, but not p38, JNK or AKT signaling. -- Highlights: ► We examine the expression of VEGFR-2 on cultured human dermal papilla (DP) cells. ► VEGF 165 stimulated proliferation of human DP cells in a dose-dependent manner. ► This stimulation was through VEGFR-2-mediated activation of ERK.

Optimization of a murine and human tissue model to recapitulate dermal and pulmonary features of systemic sclerosis.

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Tomoya Watanabe

Full Text Available The murine bleomycin (BLM-induced fibrosis model is the most widely used in systemic sclerosis (SSc studies. It has been reported that systemic delivery of BLM via continuous diffusion from subcutaneously implanted osmotic minipumps can cause fibrosis of the skin, lungs, and other internal organs. However, the mouse strain, dosage of BLM, administration period, and additional important features differ from one report to the next. In this study, by employing the pump model in C57BL/6J mice, we show a dose-dependent increase in lung fibrosis by day 28 and a transient increase in dermal thickness. Dermal thickness and the level of collagen in skin treated with high-dose BLM was significantly higher than in skin treated with low dose BLM or vehicle. A reduction in the thickness of the adipose layer was noted in both high and low dose groups at earlier time points suggesting that the loss of the fat layer precedes the onset of fibrosis. High-dose BLM also induced dermal fibrosis and increased expression of fibrosis-associated genes ex vivo in human skin, thus confirming and extending the in vivo findings, and demonstrating that a human organ culture model can be used to assess the effect of BLM on skin. In summary, our findings suggest that the BLM pump model is an attractive model to analyze the underlying mechanisms of fibrosis and test the efficacy of potential therapies. However, the choice of mouse strain, duration of BLM administration and dose must be carefully considered when using this model.

A subchronic dermal exposure study of diethylene glycol monomethyl ether and ethylene glycol monomethyl ether in the male guinea pig.

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Hobson, D W; D'Addario, A P; Bruner, R H; Uddin, D E

1986-02-01

Diethylene glycol monomethyl ether (DEGME) has been selected as a replacement anti-icing additive for ethylene glycol monomethyl ether (EGME) in Navy jet aircraft fuel. This experiment was performed to determine whether DEGME produced similar toxicity to EGME following dermal exposure. Male guinea pigs were dermally exposed to 1.00, 0.20, 0.04, or 0 (control) g/kg/day DEGME for 13 weeks, 5 days/week, 6 hr/day. Another group of animals was similarly exposed to 1.00 g/kg/day EGME. Body weights as well as testicular and splenic weights were reduced as a result of exposure to EGME, DEGME-exposed animals exhibited decreased splenic weight in the high- and medium-dose (1.00 and 0.20 g/kg/day) exposure groups only. Hematologic changes in EGME-exposed animals included mild anemia with increased erythrocytic mean corpuscular volumes and a lymphopenia with increased neutrophils. Similar hematological changes were not observed in any animals exposed to DEGME. Serum creatine kinase activity was increased in animals exposed to EGME, and serum lactate dehydrogenase activity was increased in EGME and 1.00 g/kg/day DEGME-exposed animals. In general, DEGME produced minimal toxicological changes following dermal exposure, whereas the toxicological changes observed following similar exposure to EGME were much more profound.

Bone histology sheds light on the nature of the "dermal armor" of the enigmatic sauropod dinosaur Agustinia ligabuei Bonaparte, 1999

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Bellardini, Flavio; Cerda, Ignacio A.

2017-02-01

Agustinia ligabuei is an Early Cretaceous sauropod dinosaur from the northwest of Patagonia that is currently the topic of debate with respect to its phylogenetic position and atypical dermal armor. The presence of four morphotypes of laminar and transversely elongated putative osteoderms was used to consider Agustinia as an armored sauropod. Regarding the different hypotheses about the identity of the bony structures of Agustinia (e.g., osteoderms, cervical or dorsal ribs, hypertrophied elements), a comparative histological analysis has been carried out. Histological evidence is presented herein and reveals that none of the morphotypes of Agustinia shows a primary bone tissue formed by structural fiber bundles as in other sauropod dinosaur osteoderms. Furthermore, on the basis of their gross morphology and microstructure, the bony structures originally classified as types 1 + 4 and 3 are more comparable respectively with dorsal and cervical ribs than any other kind of dermal or bony element. Due to poor preservation, the nature of the type 2 cannot be assessed but is here tentatively assigned to a pelvic girdle element. Although a phylogenetic reassessment of Agustinia is not the purpose of this paper, our paleohistological analyses have broader implications: by not supporting the dermal armor hypothesis for Agustinia, its inclusion in Lithostrotia is not justified in the absence of other diagnostic features.

The retinoic acid-induced up-regulation of insulin-like growth factor 1 and 2 is associated with prolidase-dependent collagen synthesis in UVA-irradiated human dermal equivalents.

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Shim, Joong Hyun; Shin, Dong Wook; Lee, Tae Ryong; Kang, Hak Hee; Jin, Sun Hee; Noh, Minsoo

2012-04-01

Ultraviolet (UV) A irradiation causes the degeneration of extracellular matrix in the skin dermis, mainly due to disrupted collagen homeostasis, resulting in the photo-aging of human skin. All-trans retinoic acid (ATRA) improves photo-aged human skin in vivo. Although the effects of ATRA on collagen synthesis and MMP regulation are well known, the effects of ATRA on other collagen homeostasis-associated genes have not been elucidated. This study was aimed to study the factors that are pharmacologically associated with the effect of ATRA on collagen homeostasis. The gene transcription profile of collagen homeostasis-associated genes was systematically evaluated in three-dimensional human dermal equivalents (HDEs) following UVA-irradiation and/or ATRA treatment. In addition to the expected changes in MMPs and collagen synthesis in HDEs in response to ATRA, prolidase, an important enzyme in the recycling of proline and hydroxyproline from degraded collagen molecules, was significantly decreased by UVA irradiation, and its down-regulation was antagonized by ATRA. Transfection with a prolidase-specific siRNA led to a significant decrease in procollagen synthesis in human fibroblasts. ATRA inhibited the UVA irradiation-induced decrease in prolidase activity through an insulin-like growth factor (IGF) receptor signaling pathway in HDEs. ARTA increased IGF1 and IGF2 production in HDEs, and neutralizing IGFs with anti-IGF antibodies abolished the effect of ATRA on proliase activity. These data demonstrate that ATRA regulates prolidase activity in HDEs via IGF receptor signaling, suggesting one of the pharmacological mechanisms by which improves photo-aged human skin. Copyright © 2011 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Dextran sulfate sodium-induced acute colitis impairs dermal lymphatic function in mice.

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Agollah, Germaine D; Wu, Grace; Peng, Ho-Lan; Kwon, Sunkuk

2015-12-07

To investigate whether dermal lymphatic function and architecture are systemically altered in dextran sulfate sodium (DSS)-induced acute colitis. Balb/c mice were administered 4% DSS in lieu of drinking water ad libitum for 7 d and monitored to assess disease activity including body weight, diarrhea severity, and fecal bleeding. Control mice received standard drinking water with no DSS. Changes in mesenteric lymphatics were assessed following oral administration of a fluorescently-labelled fatty acid analogue, while dermal lymphatic function and architecture was longitudinally characterized using dynamic near-infrared fluorescence (NIRF) imaging following intradermal injection of indocyanine green (ICG) at the base of the tail or to the dorsal aspect of the left paw prior to, 4, and 7 d after DSS administration. We also measured dye clearance rate after injection of Alexa680-bovine serum albumin (BSA). NIRF imaging data was analyzed to reveal lymphatic contractile activity after selecting fixed regions of interest (ROIs) of the same size in fluorescent lymphatic vessels on fluorescence images. The averaged fluorescence intensity within the ROI of each fluorescence image was plotted as a function of imaging time and the lymphatic contraction frequency was computed by assessing the number of fluorescent pulses arriving at a ROI. Mice treated with DSS developed acute inflammation with clinical symptoms of loss of body weight, loose feces/watery diarrhea, and fecal blood, all of which were aggravated as disease progressed to 7 d. Histological examination of colons of DSS-treated mice confirmed acute inflammation, characterized by segmental to complete loss of colonic mucosa with an associated chronic inflammatory cell infiltrate that extended into the deeper layers of the wall of the colon, compared to control mice. In situ intravital imaging revealed that mice with acute colitis showed significantly fewer fluorescent mesenteric lymphatic vessels, indicating impaired

Histological comparison of long-bone cortex between 11-year-old giant cow with dermal dysplasia and the child cow aged 8.5 years.

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Mori, Ryoichi; Kodaka, Tetsuo; Naito, Yoshihisa

2012-02-01

Young calves are known to be formed with laminar bone in long-bone cortex during growing periods and the osteon formation begins later. Previously, we reported that an 11-year-old giant Holstein cow with dermal dysplasia showed a delayed osteon formation. An 8.5-year-old cow, born from the giant Holstein cow, also showed some dermal dysplasia and the outer-half layer of the child almost retained laminar bone similar to that of the mother, although the body weight was approximately normal. The mother had formed the inner circumferential lamella and the child was going to form the inner circumferential lamella, but their outer circumferential lamellas were not formed yet in both of them, when compared with a 12-years-old cow as a control of the mother. Therefore, we suggest on long-bone formation pattern that the child resembled the mother rather than the control, and that the child had more or less succeeded to the mother genes of delayed osteon formation as well as dermal dysplasia which seemed to be genetic collagen disorder, although there were mild gene appearances.

Assessment of quality of life in patients with post kalaazar dermal leishmaniasis.

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Pal, Biplab; Murti, Krishna; Siddiqui, Niyamat Ali; Das, Pradeep; Lal, Chandra Shekhar; Babu, Rajendra; Rastogi, Manoj Kumar; Pandey, Krishna

2017-07-24

Post kala-azar dermal leishmaniasis (PKDL) is a dermatological disorder caused by protozoal parasite Leishmania donovani. PKDL cases are thought to be a reservoir of parasites and may increase cases of visceral leishmaniasis. The disease is not life threatening but cosmetic disfigurement associated with it may impair the patients' quality of life. This study aimed to assess the health related quality of life in patients with post kalaazar dermal leishmanasis for the first time. A total of 92 PKDL cases and 96 healthy participants filled out the questionnaires. The Dermatology Life Quality Index (DLQI) and SF 36 questionnaire were used to assess the quality of life. Data on socio-demographic and clinical features were also collected. The collected data were analyzed by using SPSS software (version 16), Student's t-test, analysis of variance (ANOVA) was applied for comparison of means. PKDL patients experienced very large impact on their quality of life. The mean score of DLQI was 11.41. Highest impact was found in symptoms and feelings and lowest impact was observed for personal relationship domain. Patients below 20 years age group found to have lower quality of life. There was a significant difference in mean DLQI scores with regard to age and severity of lesions (P  0.05). PKDL significantly impaired the patient's quality of life. Further studies to assess the impact of treatment on quality of life in these patients are recommended.

Pigment epithelium-derived factor as a multifunctional regulator of wound healing

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Wietecha, Mateusz S.; Król, Mateusz J.; Michalczyk, Elizabeth R.; Chen, Lin; Gettins, Peter G.

2015-01-01

During dermal wound repair, hypoxia-driven proliferation results in dense but highly permeable, disorganized microvascular networks, similar to those in solid tumors. Concurrently, activated dermal fibroblasts generate an angiopermissive, provisional extracellular matrix (ECM). Unlike cancers, wounds naturally resolve via blood vessel regression and ECM maturation, which are essential for reestablishing tissue homeostasis. Mechanisms guiding wound resolution are poorly understood; one candidate regulator is pigment epithelium-derived factor (PEDF), a secreted glycoprotein. PEDF is a potent antiangiogenic in models of pathological angiogenesis and a promising cancer and cardiovascular disease therapeutic, but little is known about its physiological function. To examine the roles of PEDF in physiological wound repair, we used a reproducible model of excisional skin wound healing in BALB/c mice. We show that PEDF is abundant in unwounded and healing skin, is produced primarily by dermal fibroblasts, binds to resident microvascular endothelial cells, and accumulates in dermal ECM and epidermis. PEDF transcript and protein levels were low during the inflammatory and proliferative phases of healing but increased in quantity and colocalization with microvasculature during wound resolution. Local antibody inhibition of endogenous PEDF delayed vessel regression and collagen maturation during the remodeling phase. Treatment of wounds with intradermal injections of exogenous, recombinant PEDF inhibited nascent angiogenesis by repressing endothelial proliferation, promoted vascular integrity and function, and increased collagen maturity. These results demonstrate that PEDF contributes to the resolution of healing wounds by causing regression of immature blood vessels and stimulating maturation of the vascular microenvironment, thus promoting a return to tissue homeostasis after injury. PMID:26163443

Dermal tumorigen PAH and complex mixtures for biological research

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Griest, W.H.; Guerin, M.R.; Ho, C.

1985-01-01

Thirteen commercially available, commonly reported four-five ring dermal tumorigen PAHs, were determined in a set of complex mixtures consisting of crude and upgraded coal liquids, and petroleum crude oils and their distillate fractions. Semi-preparative scale, normal phase high performance liquid chromatographic fractionation followed by capillary column gas chromatography or gas chromatography-mass spectroscopy were used for the measurements. Deuterated or carbon-14 labeled PAH served as internal standards or allowed recovery corrections. Approaches for the preparation and measurement of radiolabeled PAH were examined to provide chemical probes for biological study. Synthetic routes for production of 14 C labeled dihydrobenzo[a]pyrene and 14 C- or 3 H 10-azabenzo[a]pyrene are being studied to provide tracers for fundamental studies in tracheal transplant and skin penetration systems. (DT)

Usefulness of Cross-Linked Human Acellular Dermal Matrix as an Implant for Dorsal Augmentation in Rhinoplasty.

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Yang, Chae Eun; Kim, Soo Jung; Kim, Ji Hee; Lee, Ju Hee; Roh, Tai Suk; Lee, Won Jai

2018-02-01

Asian noses are relatively small and flat compared to Caucasians; therefore, rhinoplasty procedures often focus on dorsal augmentation and tip projection rather than reduction in the nasal framework. Various autologous and alloplastic implant materials have been used for dorsal augmentation. Recently, human acellular dermal matrices have been introduced as an implant material for dorsal augmentation, camouflaging autologous implants without an additional donor site. Here, we introduce a cross-linked human acellular dermal matrix as an implant material in augmentation rhinoplasty and share the clinical experiences. Eighteen patients who underwent augmentation rhinoplasty using acellular dermal matrix from April 2014 to November 2015 were reviewed retrospectively. Clinical outcomes and complications were assessed at the outpatient clinic during the follow-up period ranging from 8 to 38 months. Contour changes were assessed through comparison of preoperative and postoperative photographs by two independent plastic surgeons. Patient satisfaction was assessed at the outpatient clinic by six questions regarding aesthetic and functional aspects. Postoperative photographs demonstrated the height of the nasal dorsum did not decrease over time except two patients whose ADM was grafted into a subperiosteal pocket. Others who underwent supraperiosteal implantation showed acceptable maintenance of dorsal height. No major complication was reported. Overall, patient satisfaction scored 81.02 out of 100. Cross-linked human ADM has advantages of both autogenous and alloplastic materials. The surgical results remain stable without complications. Therefore, it is a suitable alternative implant material for dorsal augmentation in rhinoplasty. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Antibacterial and dermal toxicological profiles of ethyl acetate extract from Crassocephalum bauchiense (Hutch. Milne-Redh (Asteraceae

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Njateng Guy SS

2011-05-01

Full Text Available Abstract Background The emergence in recent years of numerous resistant strains of pathogenic bacteria to a range of formerly efficient antibiotics constitutes a serious threat to public health. Crassocephalum bauchiense, a medicinal herb found in the West Region of Cameroon is used to treat gastrointestinal infections as well as liver disorders. The ethyl acetate extract from the leaves of C. bauchiense was evaluated for its antibacterial activity as well as acute and sub-acute toxicities. Methods The plant extract was prepared by maceration in ethyl acetate. Its phytochemical screening was done by standard methods. The broth microdilution method was used to evaluate the in vitro antibacterial activity. The in vivo antibacterial activity of a gel formulation (0.05, 1 and 2% w/v of this extract was evaluated using a Staphylococcus aureus-induced dermatitis in a murine model. Selected haematological and biochemical parameters were used to evaluate the dermal sub-acute toxicity of the extract in rats. Results Phytochemical screening of the C. bauchiense extract revealed the presence of alkaloids, phenols, tannins and sterols. In vitro antibacterial activities were observed against all the tested microorganisms (MIC = 0.04-6.25 mg/ml. Formulated extract-gel (2% w/v and gentamycin (reference drug eradicated the microbial infection after five days of treatment. A single dermal dose of this extract up to 32 g/kg body weight (bw did not produce any visible sign of toxicity. Also, daily dermal application of the C. bauchiense extract gel formulation for 28 days did not show any negative effect, instead some biochemical parameters such as alanine aminotransferase (ALT and AST, low density lipoprotein (LDL, high density lipoprotein (HDL and triglycerides were significantly (p Conclusion These results indicate that the C. bauchiense ethyl acetate extract can be used safely for the treatment of some bacterial infections.

Evaluation of a 2-aminoimidazole variant as adjuvant treatment for dermal bacterial infections

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Draughn GL

2017-01-01

Full Text Available G Logan Draughn,1 C Leigh Allen,1 Patricia A Routh,2 Maria R Stone,2 Kelly R Kirker,3 Laura Boegli,3 Ryan M Schuchman,1 Keith E Linder,2 Ronald E Baynes,2 Garth James,3 Christian Melander,4 Angela Pollard,5 John Cavanagh1 1Department of Molecular and Structural Biochemistry, 2Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA; 3Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA; 4Department of Chemistry, North Carolina State University, Raleigh, NC, USA; 5Agile Sciences Inc., Raleigh, NC, USA Abstract: 2-Aminoimidazole (2-AI-based compounds have been shown to efficiently disrupt biofilm formation, disperse existing biofilms, and resensitize numerous multidrug-resistant bacteria to antibiotics. Using Pseudomonas aeruginosa and Staphylococcus aureus, we provide initial pharmacological studies regarding the application of a 2-AI as a topical adjuvant for persistent dermal infections. In vitro assays indicated that the 2-AI H10 is nonbactericidal, resensitizes bacteria to antibiotics, does not harm the integument, and promotes wound healing. Furthermore, in vivo application of H10 on swine skin caused no gross abnormalities or immune reactions. Taken together, these results indicate that H10 represents a promising lead dermal adjuvant compound. Keywords: transdermal absorption, antimicrobial activity, skin irritation, synergism, oroidin derivative, drip-flow reactor, ESKAPE pathogens

PAMAM dendrimer hydrogel film—biocompatible material to an efficient dermal delivery of drugs

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Magalhães, Thamiris Machado; Guerra, Rodrigo Cinti; San Gil, Rosane Aguiar da Silva; Valente, Ana Paula; Simão, Renata Antoun; Soares, Bluma Guenther; Mendes, Thamara de Carvalho; Pyrrho, Alexandre dos Santos; Sousa, Valeria Pereira de; Rodrigues-Furtado, Vanessa Lúcia

2017-08-01

We report the preparation, characterization, and drug release kinetics of a pH-responsive hydrogel film from a dendrimer megamer. The megamer (GP32) is a three-dimensional reticulated structure with a mean diameter of 71.16 nm (PDI 0.150) and was prepared by the reaction between Poly(amidoamine) generation4 (PAMAM G4) dendrimer and glutaraldehyde (G:P molar ratio 32). The crosslinking units in the megamer are provided mainly by the bicyclic dimer 2-hydroxy-3,4,4a,7,8,8a-hexahydro-2 H-chromene-6-carbaldehyde as determined by high-resolution (800 MHz) 1H NMR and FTIR. The hydrogel film (F[GP32]) is formed upon evaporation of a methanolic solution of the megamer and has a high degree of organization and homogeneity. Further crosslinking with glutaraldehyde (CLF[GP32]) enhanced the mechanical properties of the hydrogel film. The chemical constitution and unique megamer architecture enable the hydrogel film to carry both lipophilic and hydrophilic substances. The film did not cause any dermal irritation or clinical signs of toxicity in tests on rabbits, allowed for a sustained release of ketoprofen and played an important role in the process of drug delivery into the receptor medium. This performance taken together with the absence of toxicity makes this hydrogel film a good choice for dermal sustained drug release. [Figure not available: see fulltext.

Dermal toxicity elicited by phthalates: evaluation of skin absorption, immunohistology, and functional proteomics.

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Pan, Tai-Long; Wang, Pei-Wen; Aljuffali, Ibrahim A; Hung, Yi-Yun; Lin, Chwan-Fwu; Fang, Jia-You

2014-03-01

The toxicity of phthalates is an important concern in the fields of environmental health and toxicology. Dermal exposure via skin care products, soil, and dust is a main route for phthalate delivery. We had explored the effect of topically-applied phthalates on skin absorption and toxicity. Immunohistology, functional proteomics, and Western blotting were employed as methodologies for validating phthalate toxicity. Among 5 phthalates tested, di(2-ethylhexyl)phthalate (DEHP) showed the highest skin reservoir. Only diethyl phthalate (DEP) and dibutyl phthalate (DBP) could penetrate across skin. Strat-M(®) membrane could be used as permeation barrier for predicting phthalate penetration through skin. The accumulation of DEHP in hair follicles was ∼15nmol/cm(2), which was significantly greater than DBP and DEP. DBP induced apoptosis of keratinocytes and fibroblasts via caspase-3 activation. This result was confirmed by downregulation of 14-3-3 and immunohistology of TUNEL. On the other hand, the HSP60 overexpression and immunostaining of COX-2 suggested inflammatory response induced by DEP and DEHP. The proteomic profiling verified the role of calcium homeostasis on skin inflammation. Some proteins investigated in this study can be sensitive biomarkers for dermal toxicity of phthalates. These included HSPs, 14-3-3, and cytokeratin. This work provided novel platforms for examining phthalate toxicity on skin. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of a tissue-engineered human oral mucosa equivalent based on an acellular allogeneic dermal matrix: a preliminary report of clinical application to burn wounds.

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Iida, Takuya; Takami, Yoshihiro; Yamaguchi, Ryo; Shimazaki, Shuji; Harii, Kiyonori

2005-01-01

Tissue-engineered skin equivalents composed of epidermal and dermal components have been widely investigated for coverage of full-thickness skin defects. We developed a tissue-engineered oral mucosa equivalent based on an acellular allogeneic dermal matrix and investigated its characteristics. We also tried and assessed its preliminary clinical application. Human oral mucosal keratinocytes were separated from a piece of oral mucosa and cultured in a chemically-defined medium. The keratinocytes were seeded on to the acellular allogeneic dermal matrix and cultured. Histologically, the mucosa equivalent had a well-stratified epithelial layer. Immunohistochemical study showed that it was similar to normal oral mucosa. We applied this equivalent in one case with an extensive burn wound. The equivalent was transplanted three weeks after the harvest of the patient's oral mucosa and about 30% of the graft finally survived. We conclude that this new oral mucosa equivalent could become a therapeutic option for the treatment of extensive burns.

The polypeptide in Chlamys farreri can protect human dermal fibroblasts from ultraviolet B damage

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Zhang, Yujiang; Zhan, Songmei; Cao, Pengli; Liu, Ning; Chen, Xuehong; Wang, Yuejun; Wang, Chunbo

2005-09-01

To investigate the effect of polypeptide from Chlamys farreri (PCF) on NHDF in vitro, we modeled oxidative damage on normal human dermal fibroblasts (NHDF) exposed to ultraviolet B (UVB). In this study, 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) were tested to measure cell viability. Enzymes including superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), catalase (CAT) and xanthine oxidase (XOD) were determined biochemically. Total antioxidative capacity (T-AOC) and anti-superoxide anion capacity (A-SAC) were also determined. Ultrastructure of fibroblasts was observed under transmission electron microscope. The results showed that: UVB (1.176×10-4 J/cm2) suppressed the growth of fibroblasts and the introduction of PCF (0.25% 1%) before UVB reduced the suppression in a concentration-dependent manner. PCF could enhance the activities of SOD, GSH-PX and T-AOC as well as A-SAC. Also PCF could inhibit XOD activity, while it did not affect CAT activity. Ultrastructure of fibroblasts were damaged after UVB irradiation, concentration-dependent PCF reduced the destructive effect of UVB on cells. These results indicated that PCF can protect human dermal fibroblasts from being harmed by UVB irradiation via its antioxidant proerty.

Outcomes in Patients Treated with a Novel, Simple Method for Hemostasis of Dermal Avulsion Injuries.

Science.gov (United States)

Dowling, Sean Taylor; Lin, Brian Wai

2017-10-01

A recently described technique proposes a simple method to achieve permanent hemostasis of distal fingertip dermal avulsion injuries. It is simple to learn and easy to perform with readily available materials found in most emergency departments. However, long-term outcomes for patients treated with this technique have not yet been evaluated. A primary objective of the current article is to provide safety data for the technique using an off-label product indication. Emergency department of Kaiser Permanente Medical Center, San Francisco, California. Six patients were treated in the emergency department for fingertip dermal avulsion injuries using a tourniquet and tissue adhesive glue (Dermabond by Ethicon, Somerville, New Jersey). Patients were subsequently contacted to assess healing and satisfaction with cosmetic outcome through interview and photographs of their wounds at 9 months following the date of injury. All 6 patients were satisfied with the cosmetic outcome of treatment, and none received a diagnosis of serious complications. This series demonstrates cosmetic outcomes for injuries treated with the technique, highlights potential problems that may be perceived by patients during their clinical course, and creates the groundwork for a larger clinical study examining the use of the technique.

[Management of recurrent urethrocutaneous fistula after hypospadias surgery in pediatric patients: initial experience with dermal regeneration sheet Integra].

Science.gov (United States)

Casal-Beloy, I; Somoza Argibay, I; García-González, M; García-Novoa, A M; Míguez Fortes, L; Blanco, C; Dargallo Carbonell, T

2017-10-25

To present our initial experience using a dermal regeneration sheet as an urethral cover in the repair of recurrent urethrocutaneous fistulae in pediatric patients. Since May 2016 to March a total of 8 fistulaes were repaired using this new technique. We performed the ddissection of the fistulous tract and posterior closure of the urethral defect. A dermal regeneration sheet was used to cover the urethral suture. Finally a rotational flap was performed to avoid overlap sutures. During the follow-up (average 6 months), one patient presented in the immediate postoperative period infection of the surgical wound. This patient presented recurrence of the fistula. 88% of the patients included presented a good evolution with no other complications. In our initial experience the new technique seems easy, safe and effective in the management of the recurrent urethrocutaneous fistulae in pediatric patients. More studies are needed to prove these results.

Potential of the octanol-water partition coefficient (logP) to predict the dermal penetration behaviour of amphiphilic compounds in aqueous solutions.

Science.gov (United States)

Korinth, Gintautas; Wellner, Tanja; Schaller, Karl Heinz; Drexler, Hans

2012-11-23

Aqueous amphiphilic compounds may exhibit enhanced skin penetration compared with neat compounds. Conventional models do not predict this percutaneous penetration behaviour. We investigated the potential of the octanol-water partition coefficient (logP) to predict dermal fluxes for eight compounds applied neat and as 50% aqueous solutions in diffusion cell experiments using human skin. Data for seven other compounds were accessed from literature. In total, seven glycol ethers, three alcohols, two glycols, and three other chemicals were considered. Of these 15 compounds, 10 penetrated faster through the skin as aqueous solutions than as neat compounds. The other five compounds exhibited larger fluxes as neat applications. For 13 of the 15 compounds, a consistent relationship was identified between the percutaneous penetration behaviour and the logP. Compared with the neat applications, positive logP were associated with larger fluxes for eight of the diluted compounds, and negative logP were associated with smaller fluxes for five of the diluted compounds. Our study demonstrates that decreases or enhancements in dermal penetration upon aqueous dilution can be predicted for many compounds from the sign of logP (i.e., positive or negative). This approach may be suitable as a first approximation in risk assessments of dermal exposure. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Simultaneous and multi-point measurement of ammonia emanating from human skin surface for the estimation of whole body dermal emission rate.

Science.gov (United States)

Furukawa, Shota; Sekine, Yoshika; Kimura, Keita; Umezawa, Kazuo; Asai, Satomi; Miyachi, Hayato

2017-05-15

Ammonia is one of the members of odor gases and a possible source of odor in indoor environment. However, little has been known on the actual emission rate of ammonia from the human skin surface. Then, this study aimed to estimate the whole-body dermal emission rate of ammonia by simultaneous and multi-point measurement of emission fluxes of ammonia employing a passive flux sampler - ion chromatography system. Firstly, the emission fluxes of ammonia were non-invasively measured for ten volunteers at 13 sampling positions set in 13 anatomical regions classified by Kurazumi et al. The measured emission fluxes were then converted to partial emission rates using the surface body areas estimated by weights and heights of volunteers and partial rates of 13 body regions. Subsequent summation of the partial emission rates provided the whole body dermal emission rate of ammonia. The results ranged from 2.9 to 12mgh -1 with an average of 5.9±3.2mgh -1 per person for the ten healthy young volunteers. The values were much greater than those from human breath, and thus the dermal emission of ammonia was found more significant odor source than the breath exhalation in indoor environment. Copyright © 2017 Elsevier B.V. All rights reserved.

Human skin gene expression: Natural (trans) resveratrol versus five resveratrol analogs for dermal applications.

Science.gov (United States)

Lephart, Edwin D; Andrus, Merritt B

2017-09-01

Resveratrol (RV) is a polyphenolic compound naturally produced by plants. Polyphenolic compounds incorporated into medicinal products are beneficial but, RV is rapidly metabolized with an associated decline in biological activity. This study tested RV as the standard and compared five structurally modified RV analogs: butyrate, isobutyrate, palmitoate, acetate, and diacetate (to improve functionality) at 1% concentration(s) for 24 h in epiderm full thickness cultures by gene array/qPCR mRNA analysis. When silent mating type information regulation 2 homolog 1, extracellular elements (collagen1A1, 3A1, 4A1; elastin, tissue inhibitor of matrix metalloproteinase 1, fibrillin 1 laminin beta1 and matrix metalloproteinase 9), anti-aging and aging genes, inflammatory biomarkers (interleukin-1A [IL1A], IL1R2, IL-6 and IL-8), nerve growth factor, and the antioxidants (proliferating cell nuclear antigen, catalase, superoxide dismutase and metallothionein 1H/2H) were evaluated, ranking each from highest-to-lowest for gene expression: butyrate > isobutyrate > diacetate > acetate > palmitoate. This study showed that the butyrate and isobutyrate analogs are more biologically active compared to resveratrol and have potential use in topical applications to improve dermal and other health applications. Impact statement Resveratrol has been reported to have a wide variety of health benefits but its rapid metabolism especially after oral ingestion results in very low bioavailability. Notably, the first human skin gene expression study of resveratrol was not published until 2014. The purpose of this study was to determine if increased stability and biological activity could be obtained by modifying the chemical structure of natural (trans) resveratrol and quantifying human gene expression by qPCR of skin biomarkers that enhance dermal health. Five resveratrol analogs were synthesized that increased their lipophilic index to enhance tissue penetration and augment

Inhibition of Methylglyoxal-Induced AGEs/RAGE Expression Contributes to Dermal Protection by N-Acetyl-L-Cysteine

Directory of Open Access Journals (Sweden)

Chun-tao Yang

2017-02-01

Full Text Available Background/Aim: Accumulation of advanced glycation end products (AGEs is a major cause of diabetes mellitus (DM skin complications. Methylglyoxal (MGO, a reactive dicarbonyl compound, is a crucial intermediate of AGEs generation. N-acetyl-L-cysteine (NAC, an active ingredient of some medicines, can induce endogenous GSH and hydrogen sulfide generation, and set off a condensation reaction with MGO. However, there is rare evidence to show NAC can alleviate DM-induced skin injury through inhibition of AGEs generation or toxicity. The present study aimed to observe the effects of NAC on MGO-induced inflammatory injury and investigate the roles of AGEs and its receptor (RAGE in NAC’s dermal protection in human HaCaT keratinocytes. Methods: The cells were exposed to MGO to simulate a high MGO status in diabetic blood or tissues. The content of AGEs in serum or cell medium was measured with ELISA. The protective effects of NAC against MGO-induce injury were evaluated by administration before MGO one hour, in virtue of cell viability, mitochondrial membrane potential, inflammation reaction, nuclear factor (NF-κB activation, matrix metalloproteinase (MMP-9 expression, as well as cellular behavioral function. Results: We found the AGEs levels of patients with DM were elevated comparing with healthy volunteers. The in vitro AGEs generation was also able to be enhanced by the exposure of HaCaT cells to MGO, which reduced dose-dependently cellular viability, damaged mitochondrial function, triggered secretion of interleukin (IL-6 and IL-8, activated NF-κB and upregulated MMP-9 expression. Furthermore, the exposure caused cellular adhesion and migration dysfunction, as well as collagen type I inhibition. Importantly, before the exposure to MGO, the preconditioning with NAC significantly attenuated MGO-induced AGEs generation, improved cellular viability and mitochondrial function, partially reversed the overexpression of proinflammatory factors and MMP-9

In vitro human epidermal permeation of nicotine from electronic cigarette refill liquids and implications for dermal exposure assessment.

Science.gov (United States)

Frasch, H Frederick; Barbero, Ana M

2017-11-01

Nicotine plus flavorings in a propylene glycol (PG) vehicle are the components of electronic cigarette liquids (e-liquids), which are vaporized and inhaled by the user. Dermal exposure to nicotine and e-liquids may occur among workers in mixing and filling of e-cigarettes in the manufacturing process. Inadvertent skin contact among consumers is also a concern. In vitro nicotine permeation studies using heat-separated human epidermis were performed with surrogate and two commercial e-liquids, neat and aqueous nicotine donor formulations. Steady-state fluxes (J ss ), and lag times (t lag ) were measured for each formulation. In addition, transient (4 h) exposure and finite dose (1-10 μl/cm 2 ) experiments were undertaken using one commercial e-liquid. Average J ss (μg/cm 2 /h) from formulations were: nicotine in PG (24 mg/ml): 3.97; commercial e-liquid containing menthol (25 mg/ml nicotine): 10.2; commercial e-liquid containing limonene (25 mg/ml nicotine): 23.7; neat nicotine: 175. E-liquid lag times ranged from 5 to 10 h. Absorbed fraction of nicotine from finite doses was ≈0.3 at 48 h. The data were applied to transient exposure and finite dose dermal exposure assessment models and to a simple pharmacokinetic model. Three illustrative exposure scenarios demonstrate use of the data to predict systemic uptake and plasma concentrations from dermal exposure. The data demonstrate the potential for significant nicotine absorption through skin contact with e-cigarette refill solutions and the neat nicotine used to mix them.

Ultraviolet-B Protective Effect of Flavonoids from Eugenia caryophylata on Human Dermal Fibroblast Cells

OpenAIRE

Patwardhan, Juilee; Bhatt, Purvi

2015-01-01

Background: The exposure of skin to ultraviolet-B (UV-B) radiations leads to deoxyribonucleic acid (DNA) damage and can induce production of free radicals which imbalance the redox status of the cell and lead to increased oxidative stress. Clove has been traditionally used for its analgesic, anti-inflammatory, anti-microbial, anti-viral, and antiseptic effects. Objective: To evaluate the UV-B protective activity of flavonoids from Eugenia caryophylata (clove) buds on human dermal fibroblast c...

Epilobium angustifolium extract demonstrates multiple effects on dermal fibroblasts in vitro and skin photo-protection in vivo.

Science.gov (United States)

Ruszová, Ema; Cheel, José; Pávek, Stanislav; Moravcová, Martina; Hermannová, Martina; Matějková, Ilona; Spilková, Jiřina; Velebný, Vladimír; Kubala, Lukáš

2013-09-01

Stress-induced fibroblast senescence is thought to contribute to skin aging. Ultraviolet light (UV) radiation is the most potent environmental risk factor in these processes. An Epilobium angustifolium (EA) extract was evaluated for its capacity to reverse the senescent response of normal human dermal fibroblasts (NHDF) in vitro and to exhibit skin photo-protection in vivo. The HPLC-UV-MS analysis of the EA preparation identified three major polyphenol groups: tannins (oenothein B), phenolic acids (gallic and chlorogenic acids) and flavonoids. EA extract increased the cell viability of senescent NHDF induced by serum deprivation. It diminished connective tissue growth factor and fibronectin gene expressions in senescent NHDF. Down-regulation of the UV-induced release of both matrix metalloproteinase-1 and -3 and the tissue inhibitor of matrix metalloproteinases-1 and -2, and also down-regulation of the gene expression of hyaluronidase 2 were observed in repeatedly UV-irradiated NHDF after EA extract treatment. Interestingly, EA extract diminished the down-regulation of sirtuin 1 dampened by UV-irradiation. The application of EA extract using a sub-irritating dose protected skin against UV-induced erythema formation in vivo. In summary, EA extract diminished stress-induced effects on NHDF, particularly on connective tissue growth factor, fibronectin and matrix metalloproteinases. These results collectively suggest that EA extract may possess anti-aging properties and that the EA polyphenols might account for these benefits.

Amelogenin is phagocytized and induces changes in integrin configuration, gene expression and proliferation of cultured normal human dermal fibroblasts

DEFF Research Database (Denmark)

Almqvist, Sofia; Werthén, Maria; Johansson, Anna

2010-01-01

Fibroblasts are central in wound healing by expressing important mediators and producing and remodelling extracellular matrix (ECM) components. This study aimed at elucidating possible mechanisms of action of the ECM protein amelogenin on normal human dermal fibroblasts (NHDF). Amelogenin at 100...

Dermal uptake and percutaneous penetration of ten flame retardants in a human skin ex vivo model

DEFF Research Database (Denmark)

Frederiksen, Marie; Vorkamp, Katrin; Jensen, Niels Martin

2016-01-01

The dermal uptake and percutaneous penetration of ten organic flame retardants was measured using an ex vivo human skin model. The studied compounds were DBDPE, BTBPE, TBP-DBPE, EH-TBB, BEH-TEBP, α, β and γ-HBCDD as well as syn- and anti-DDC-CO. Little or none of the applied flame retardants...

A Comparative Dermal Microdialysis Study of Diclofenac QPS versus Conventional 1% Diclofenac Gel

OpenAIRE

Sanjay Kumar H. Maroo; Ketan R. Patel; Vipul Prajapati; Rajen Shah; Milind Bagul; Rakesh U. Ojha

2013-01-01

The study was designed to evaluate penetration of diclofenac through skin after application of diclofenac 4 % quick penetrating solution (Dynapar QPS) versus conventional diclofenac 1% gel. In this 2 way crossover study, 6 male healthy human subjects were randomized to receive either 1 mg of diclofenac of the Dynapar QPS (25µl) or 1 mg of diclofenac from gel (100 mg) on to the marked area of the forearm three times daily for 3 days. On day 4, after 10th application, the dermal microdialysis w...

Invasion of melanoma cells into dermal connective tissue in vitro: evidence for an important role of cysteine proteases.

NARCIS (Netherlands)

Dennhofer, R.; Kurschat, P.; Zigrino, P.; Klose, A.; Bosserhoff, A.; Muijen, G.N.P. van; Krieg, T.; Mauch, C.; Hunzelmann, N.

2003-01-01

Invasion of melanoma cells into the dermal connective tissue is a major characteristic in the complex process of metastasis. Proteases play an important role in tumor cell invasion as these enzymes are able to degrade most components of the extracellular matrix (ECM), and thus enable cells to

Oral seal using glue: a new method to distinguish between intestinal and dermal uptake of metals in earthworms.

NARCIS (Netherlands)

Vijver, M.G.; Vink, J.P.M.; Miermans, C.J.H.; van Gestel, C.A.M.

2003-01-01

Earthworms may take up chemicals from soil and pore water, both through their skin (dermal) and by ingestion (oral). It remains unclear, however, what the relative importance of these pathways is. To assess bioavailability of pollutants in soil to earthworms, it is necessary that the contribution of

Dermal Titanium Dioxide Deposition Associated With Intralesional Triamcinolone Injection.

Science.gov (United States)

Cohen, Brandon E; Bashey, Sameer; Cole, Christine; Abraham, Jerrold L; Ragsdale, Bruce; Ngo, Binh

2016-12-01

Cutaneous discoloration secondary to dermal deposition of titanium dioxide (TiO2) particles is recognized but seldom reported in the literature. In this report, the authors describe the case of a 61-year-old gentleman, with a long history of alopecia areata, who presented with numerous, discrete dark blue macules on the scalp. Scanning electron microscopy with energy dispersive x-ray spectroscopy analysis ultimately identified the macules as deposits of TiO2. The patient had a history of intralesional triamcinolone injections for management of alopecia areata. A sample of generic 0.1% triamcinolone acetonide paste was analyzed and found to contain many TiO2 particles analogous to those seen in the patient's biopsy sample. To the authors' knowledge, this is the first reported case of TiO2 deposition in the dermis likely resulting from topical combined with intralesional triamcinolone injection.

Dermal uptake of polycyclic aromatic hydrocarbons after hairwash with coal-tar shampoo

Energy Technology Data Exchange (ETDEWEB)

Schooten, F.-J. van; Moonen, E.J.C.; Rhijnsburger, E.; Agen, B. van; Thijssen, H.H.W.; Kleinjans, J.C.S. [University of Limburg, Maastricht (Netherlands). Dept. of Health Risk Analysis and Toxicology

1994-11-26

Describes an experiment to assess the dermal uptake of polycyclic aromatic hydrocarbons (PAHs) after hairwashing with coal tar antidandruff shampoo. The urinary excretion of 1-hydroxypyrene (1-OH-P), a PAH metabolile was used to assess internal dose of PAH. A single use of coal tar shampoo resulted in increased 1-OH-P excretion in all members of the experimental group compared with the control group using a non-coal tar antidandruff shampoo. It is suggested that repeated use of coal tar shampoo would result in a high internal dose of carcinogenic PAH. 5 refs., 1 fig.

Dispersal of radioisotope labelled solution following deep dermal injection in Ehlers-Danlos syndrome.

Science.gov (United States)

Oliver, D W; Balan, K K; Burrows, N P; Hall, P N

2000-06-01

Ehlers-Danlos syndrome (EDS) is the commonest inherited disorder of connective tissue, affecting around 10 000 patients in the UK. Patients with EDS have reported that local anaesthetic is often ineffective. Patients with less severe skin laxity often have the most problems. We have postulated that this resistance to local anaesthetics is not due to the lax connective tissues as is often assumed. This study used radioactively labelled solution ((99m)Tc-pertechnetate) administered as a deep dermal injection in the forearm. The rate of dispersal of isotope was measured over 60 min and found to be identical between six patients with EDS and three controls. The effects of local anaesthetics are complex and depend on the individual chemical properties of the agent and a number of tissue factors. This study would suggest that the lack of effectiveness of local anaesthetic solutions is not due to rapid dispersal of solution. It is unlikely therefore that its lack of effect can be compensated for by simply increasing the amount used. The diagnosis of EDS should be considered in any patient who complains unexpectedly of pain during their procedure, particularly when the surgeon knows that an adequate volume of local anaesthetic has been used. Copyright 2000 The British Association of Plastic Surgeons.

Increased susceptibility of skin from HERDA (Hereditary Equine Regional Dermal Asthenia)-affected horses to bacterial collagenase degradation: a potential contributing factor to the clinical signs of HERDA.

Science.gov (United States)

Rashmir-Raven, Ann; Lavagnino, Michael; Sedlak, Aleksa; Gardner, Keri; Arnoczky, Steven

2015-12-01

Hereditary equine regional dermal asthenia (HERDA) is a genetic disorder of collagen resulting in fragile, hyper-extensible skin and ulcerative lesions. The predominance of skin lesions have been shown to occur on the dorsum of HERDA-affected horses. While this has been postulated to be due to increased exposure to sunlight of these areas, the precise pathological mechanism which causes this to occur is unclear. We hypothesized that an increase in collagenase activity, that has been associated with the exposure of dermal fibroblasts to sunlight, will significantly degrade the material properties of skin from HERDA-affected horses when compared to unaffected controls. Six unaffected and seven HERDA-affected horses, all euthanized for other reasons. Full-thickness skin samples from similar locations on each horse were collected and cut into uniform strips and their material properties (tensile modulus) determined by mechanical testing before (n = 12 samples/horse) or after (n = 12 samples/horse) incubation in bacterial collagenase at 37°C for 6 h. The change in modulus following treatment was then compared between HERDA-affected and unaffected horses using a Student's t-test. The modulus of skin from HERDA-affected horses decreased significantly more than that from unaffected horses following collagenase treatment (54 ± 7% versus 30 ± 16%, P = 0.004). The significant decrease in the modulus of skin from HERDA-affected horses following collagenase exposure suggests that their altered collagen microarchitecture is more susceptible to enzymatic degradation and may explain the localization of skin lesions in HERDA-affected horses to those areas of the body most exposed to sunlight. These findings appear to support the previously reported benefits of sunlight restriction in HERDA-affected horses. © 2015 ESVD and ACVD.

Repair of Primary Cleft Palate and Oronasal Fistula With Acellular Dermal Matrix: A Systematic Review and Surgeon Survey.

Science.gov (United States)

Simpson, Andrew; Samargandi, Osama A; Wong, Alison; Graham, M Elise; Bezuhly, Michael

2018-01-01

The current review and survey aim to assess the effectiveness of acellular dermal matrix (ADM) in the repair of cleft palate and oronasal fistula and to evaluate the current trends of ADM use in palate surgery. A systematic review of English articles was conducted using MEDLINE (1960 to July 1, 2016), the Cochrane Controlled Trials Register (1960 to July 1, 2016), and EMBASE (1991 to July 1, 2016). Additional studies were identified through a review of references cited in initially identified articles. Search terms included "cleft palate," "palatal," "oronasal fistula," "acellular dermal matrix," and "Alloderm®." An online survey was disseminated to members of the American Cleft Palate-Craniofacial Association to assess current trends in ADM use in palate surgery. All studies evaluating the outcome of primary palate repair or repair of oronasal fistula with the use of aceullar dermal matrix products were included in the review. Twelve studies met inclusion criteria for review. Studies were generally of low quality, as indicated by methodological index for non-randomized studies (MINORS) scores ranging from 7 to 14. The pooled estimate for fistula formation after primary palatoplasty following ADM use was 7.1%. The pooled estimate for recurrence of fistula after attempted repair using ADM was 11%. Thirty-six cleft surgeons responded to the online survey study. Of these, 45% used ADM in primary cleft palate repair, while 67% used ADM for repair of oronasal fistulae. Use of ADM products is commonplace in palate surgery. Despite this, there is a paucity of high-quality data demonstrating benefit. Further randomized controlled trials examining ADM in palate surgery are required to help develop structured guidelines and improve care.

Strawberry-Based Cosmetic Formulations Protect Human Dermal Fibroblasts against UVA-Induced Damage

Directory of Open Access Journals (Sweden)

Massimiliano Gasparrini

2017-06-01

Full Text Available Extreme exposure of skin to Ultraviolet A (UVA-radiation may induce a dysregulated production of reactive oxygen species (ROS which can interact with cellular biomolecules leading to oxidative stress, inflammation, DNA damage, and alteration of cellular molecular pathways, responsible for skin photoaging, hyperplasia, erythema, and cancer. For these reasons, the use of dietary natural bioactive compounds with remarkable antioxidant activity could be a strategic tool to counteract these UVA-radiation-caused deleterious effects. Thus, the purpose of the present work was to test the efficacy of strawberry (50 μg/mL-based formulations supplemented with Coenzyme Q10 (100 μg/mL and sun protection factor 10 in human dermal fibroblasts irradiated with UVA-radiation. The apoptosis rate, the amount of intracellular reactive oxygen species (ROS production, the expression of proteins involved in antioxidant and inflammatory response, and mitochondrial functionality were evaluated. The results showed that the synergic topical use of strawberry and Coenzyme Q10 provided a significant (p < 0.05 photoprotective effect, reducing cell death and ROS, increasing antioxidant defense, lowering inflammatory markers, and improving mitochondrial functionality. The obtained results suggest the use of strawberry-based formulations as an innovative, natural, and useful tool for the prevention of UVA exposure-induced skin diseases in order to decrease or substitute the amount of synthetic sunscreen agents.

"The blood pressure and dermal sensitivity effects of Nylon hollow fiber releasing Glycerin Trinitrate in vivo "

Directory of Open Access Journals (Sweden)

"Ostad SN

2002-09-01

Full Text Available In order to improve patient's compliance in taking glycerine trinitrate (GTN nylon hollow fiber which has been successfully used for release of chlorhexidine diacetate and levonorgestrel was employed to make nylon hollow fiber releasing GTN. Hollow nylon fibres of external diameter 0.63 mm, 75 mm long with an internal capacity of 16 μl, were filled with GTN (190 mg/ml in 70% ethanol (v/v or vehicle alone and the ends were heat-sealed. The fibers were then immersed in 10 ml of 0.9% (w/v saline in a separating funnel. The GTN release pattern from fiber, the effect of the product on blood pressure and its potential dermal toxicity were assessed. The release of GTN from the fibres was approximately 2.7 μg/min when the fibres contained 16 mg of drug. The results showed that the amount of GTN within the single fibre was enough to reduce blood pressure significantly, while it did not show significant dermal toxicity. It is concluded that GTN fiber, if used as monofilament, is not an alternative method for GTN delivery.

The role of sialoadenectomy and epıdermal growth factor (EGF) in ...

African Journals Online (AJOL)

USER

2010-05-17

May 17, 2010 ... result, epidermal growth factor was concluded to have an important role in skin development. Key words: Epidermal growth factor, ... sialoadenectomy on epiderm and the role of EGF and antiserum EGF in prevention of .... remarkable finding in skin healing of sialoadenectomy and normal rats. According to ...

Effects of photodynamic therapy on dermal fibroblasts from xeroderma pigmentosum and Gorlin-Goltz syndrome patients.

Science.gov (United States)

Zamarrón, Alicia; García, Marta; Río, Marcela Del; Larcher, Fernando; Juarranz, Ángeles

2017-09-29

PDT is widely applied for the treatment of non-melanoma skin cancer pre-malignant and malignant lesions (actinic keratosis, basal cell carcinoma and in situ squamous cell carcinoma). In photodynamic therapy (PDT) the interaction of a photosensitizer (PS), light and oxygen leads to the formation of reactive oxygen species (ROS) and thus the selective tumor cells eradication. Xeroderma pigmentosum (XP) and Gorlin-Goltz Syndrome (GS) patients are at high risk of developing skin cancer in sun-exposed areas. Therefore, the use of PDT as a preventive treatment may constitute a very promising therapeutic modality for these syndromes. Given the demonstrated role of cancer associated fibroblasts (CAFs) in tumor progression and the putative CAFs features of some cancer-prone genodermatoses fibroblasts, in this study, we have further characterized the phenotype of XP and GS dermal fibroblasts and evaluated their response to methyl-δ-aminolevulinic acid (MAL)-PDT compared to that of dermal fibroblasts obtained from healthy donors. We show here that XP/GS fibroblasts display clear features of CAFs and present a significantly higher response to PDT, even after being stimulated with UV light, underscoring the value of this therapeutic approach for these rare skin conditions and likely to other forms of skin cancer were CAFs play a major role.

Wound healing properties of ethyl acetate fraction of Moringa oleifera in normal human dermal fibroblasts

Directory of Open Access Journals (Sweden)

Sivapragasam Gothai

2016-03-01

Full Text Available Background/Aim: Wounds are the outcome of injuries to the skin that interrupt the soft tissue. Healing of a wound is a complex and long-drawn-out process of tissue repair and remodeling in response to injury. A large number of plants are used by folklore traditions for treatment of cuts, wounds and burns. Moringa oleifera is an herb used as traditional folk medicine for the treatment of various skin wounds and associated diseases. The underlying mechanisms of wound healing activity of ethyl acetate fraction of M. oleifera leaves extract are completely unknown. Methods: In the current study, ethyl acetate fraction of Moringa oleifera leaves was investigated for its efficacy on cell viability, proliferation and migration (wound closure rate in human normal dermal fibroblast cells. Results: Results revealed that lower concentration (12.5 µg/ml, 25 µg/ml, and 50 µg/ml of ethyl acetate fraction of M. oleifera leaves showed remarkable proliferative and migratory effect on normal human dermal fibroblasts. Conclusion: The present study suggested that ethyl acetate fraction of M. oleifera leaves might be a potential therapeutic agent for skin wound healing by promoting fibroblast proliferation and migration through increasing the wound closure rate corroborating its traditional use. [J Complement Med Res 2016; 5(1.000: 1-6

In vitro studies to evaluate the antioxidant property of salidroside and rosavin and protective effects of electron beam radiation induced damages in human dermal fibroblasts

International Nuclear Information System (INIS)

Tejashvi, Kedilaya R.; Padma, Shetty K.; Suchetha Kumari, N.

2014-01-01

Rosavin and Salidroside are active component of Rhodiola rosea, it is a phenylpropanoid derivative of plant. Rhodiola rosea, also known as 'golden root' or 'roseroot' belongs to the plant family Crassulaceae. Rhodiola grows primarily in dry sandy ground at high altitudes in the arctic areas of Europe and Asia. Plant is rich with phenolic compounds, known to have a strong antioxidant property. Studies have shown that Rhodiola rosea has a capacity to decrease toxicity of Adriamycin (anti-cancer drugs), while it enhances their anti-carcinogenic effects. Enhanced antioxidant activity of Rhodiola rosea play role in the prevention of both chronic disease and aging. Present study is aimed to determine the antioxidant property of Rosavin and Salidroside and dose determination on human dermal fibroblast against dermal fibroblast. Rosavin and Salidroside were dissolved in 10% DMSO. Invitro biochemical assays like DPPH radical scavenging assay, Ferric Anion Reducing Potential using TPTZ, Nitric Oxide scavenging assay, Total antioxidant determination assay, Super Anion Radical Scavenging assays were carried out to know property of the extract. Extracts were then treated on monolayer dermal fibroblast cells survival assay was performed. Salidroside has shown 80% total antioxidant property compare to Rosavin with respect Ascorbic acid as a standard. 100'R concentration of Salidroside and Rosavin has quite equal potential to scavenging DPPH similar like Ascorbic acid. Ferric Anion Reducing Potential using TPTZ, Nitric Oxide scavenging assays have also shown both Salidroside and Rosavin has a good antioxidant property. Invitro studies on dermal fibroblast have shown remarkable protective effect on normal and irradiated groups. (author)

Chum salmon egg extracts induce upregulation of collagen type I and exert antioxidative effects on human dermal fibroblast cultures

Science.gov (United States)

Yoshino, Atsushi; Polouliakh, Natalia; Meguro, Akira; Takeuchi, Masaki; Kawagoe, Tatsukata; Mizuki, Nobuhisa

2016-01-01

Components of fish roe possess antioxidant and antiaging activities, making them potentially very beneficial natural resources. Here, we investigated chum salmon eggs (CSEs) as a source of active ingredients, including vitamins, unsaturated fatty acids, and proteins. We incubated human dermal fibroblast cultures for 48 hours with high and low concentrations of CSE extracts and analyzed changes in gene expression. Cells treated with CSE extract showed concentration-dependent upregulation of collagen type I genes and of multiple antioxidative genes, including OXR1, TXNRD1, and PRDX family genes. We further conducted in silico phylogenetic footprinting analysis of promoter regions. These results suggested that transcription factors such as acute myeloid leukemia-1a and cyclic adenosine monophosphate response element-binding protein may be involved in the observed upregulation of antioxidative genes. Our results support the idea that CSEs are strong candidate sources of antioxidant materials and cosmeceutically effective ingredients. PMID:27621603

Dermal Uptake of Organic Vapors Commonly Found in Indoor Air

DEFF Research Database (Denmark)

Weschler, Charles J.; Nazaroff, William W

2014-01-01

Transdermal uptake directly from air is a potentially important yet largely overlooked pathway for human exposure to organic vapors indoors. We recently reported (Indoor Air 2012, 22, 356) that transdermal uptake directly from air could be comparable to or larger than intake via inhalation for many......, formaldehyde, and acrolein. Analysis of published experimental data for human subjects for twenty different organic compounds substantiates these model predictions. However, transdermal uptake rates from air have not been measured for the indoor organics that have the largest modeled ratios of dermal......-to-inhalation uptake; for such compounds, the estimates reported here require experimental verification. In accounting for total exposure to indoor organic pollutants and in assessing potential health consequences of such exposures, it is important to consider direct transdermal absorption from air....

[Application of the xenogenic acellular dermal matrix membrane application used in the postoperative tissue shortage repair].

Science.gov (United States)

Bai, Yanxia; Yan, Liying; Zhang, Shaoqiang; Shao, Yuan; Yao, Xiaobao; Li, Honghui; Zhao, Ruimin; Zhao, Qian; Zhang, Pengfei; Yang, Qi

2014-09-01

To observe the short-term and long-term curative effect of the xenogenic acellular dermal matrix membrane (or joint muscle flap transfer) application used in the 82 cases postoperative tissue shortage repair that after the head neck carcinoma resection. To held the 82 cases head neck carcinoma postoperative mucosa shortage repaired after resection by the xenogenic acellular dermal matrix membrane (or joint muscle flap transfer), 65 cases mucosa shortage wound be directly covered by the repair membrane and the other 17 cases mucosa shortage wound be repaired by the tranfered muscle tissue flap with the repair membrane covered; 53 cases underwent additional postoperative radiotherapy between 2-4 weeks and follow-up in 1, 3, 6, 12, 18, 24, 30, 36, 48, 60 months and observed the operation site repair process through the electronic laryngoscope, observed the patients respiration, swallow, phonation function. Seventy-seven cases patients operation incision reached I phase healing standard, another 5 cases patients operation incision reached II phase healing standard because of the wound infection and fully-recovered through the local wound drainage,dressing process. All the patients tracheal cannula,the stomach tube be extubated successfully and without the local cicatricial constriction occurred. Seventy-eight cases follow up period reached 1 year including 53 cases who underwent postoperative radiotherapy, 49 cases follow up period reached 3 years including 32 cases who underwent postoperative radiotherapy, 14 cases follow up period reached 5 years including 12 cases who underwent postoperative radiotherapy. The patients with static local lesions discovered no reaction such as exclusion, allergy. The application of xenogenic acellular dermal matrix membrane (or joint muscle flap transfer used in in the postoperative tissue shortage repair that after the head neck carcinoma resection have several advantage such as comparatively easily implementation, operation safety

Risk of Children’s Dermal Exposure to Galaxolide through Personal Care Products

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Patrícia Correia

2015-04-01

Full Text Available Galaxolide is the most used fragrance since the early 1990s, and it has been largely detected in environmental and biological matrices. This polycyclic musk is present in almost all of our daily products, so the risk of human exposure is substantial, as it had been proved by its detection in human tissues and fluids. Due to the lack of information about the concentrations found in consumer products, monitoring data is needed for exposure assessment purposes. Dermal contact, mostly by personal care products, seems to be the major route of human exposure to galaxolide, and, due to the immaturity of young children’s skin, exposure consequences can be worse in this population. The main objective of this study was to evaluate galaxolide levels in personal care products used by children of Oporto (Portugal, aged 0–5 years, and relate it with consumer habits. Consumer patterns were obtained through 250 questionnaires to caregivers of Oporto children. The 79 most used products were extracted by a dispersive solid phase extraction methodology known as QuEChERS and galaxolide was determined by High Performance Liquid Chromatography (HPLC with fluorescence detection. The concentrations ranged between 0.001 ± 0.001 mg·kg−1, on a baby wipe, and 300.480 ± 8.819 mg·kg−1, on glycerin soap, which may correspond to an estimated daily dermal exposure of 277.10 ± 0.02 µg·day−1 on the population of Oporto children. This value is in the range of the results observed for adults, although no information of toxicological risk for children is available.

The small Rho GTPase Rac1 controls normal human dermal fibroblasts proliferation with phosphorylation of the oncoprotein c-myc

International Nuclear Information System (INIS)

Nikolova, Ekaterina; Mitev, Vanio; Zhelev, Nikolai; Deroanne, Christophe F.; Poumay, Yves

2007-01-01

Proliferation of dermal fibroblasts is crucial for the maintenance of skin. The small Rho GTPase, Rac1, has been identified as a key transducer of proliferative signals in various cell types, but in normal human dermal fibroblasts its significance to cell growth control has not been studied. In this study, we applied the method of RNA interference to suppress endogenous Rac1 expression and examined the consequences on human skin fibroblasts. Rac1 knock-down resulted in inhibition of DNA synthesis. This effect was not mediated by inhibition of the central transducer of proliferative stimuli, ERK1/2 or by activation of the pro-apoptotic p38. Rather, as a consequence of the suppressed Rac1 expression we observed a significant decrease in phosphorylation of c-myc, revealing for the first time that in human fibroblasts Rac1 exerts control on proliferation through c-myc phosphorylation. Thus Rac1 activates proliferation of normal fibroblasts through stimulation of c-myc phosphorylation without affecting ERK1/2 activity

The sun protection factor (SPF) inadequately defines broad spectrum photoprotection: demonstration using skin reconstructed in vitro exposed to UVA, UVBor UV-solar simulated radiation.

Science.gov (United States)

Bernerd, Françoise; Vioux, Corinne; Lejeune, François; Asselineau, Daniel

2003-01-01

Wavelength specific biological damage has been previously identified in human skin reconstructed in vitro. Sunburn cell and pyrimidine dimers were found after UVB exposure, and alterations of dermal fibroblasts after UVA exposure. These damages permitted us to discriminate UVB and UVA single absorbers. The present study shows that these biological effects can be obtained simultaneously by a combined UVB + UVA exposure using ultraviolet solar simulated light (UV-SSR), which represents a relevant UV source. In addition, the protection afforded by two broad spectrum sunscreen complex formulations was assessed after topical application. These two formulations displayed the same sun protection factor but different UVA protection factors determined by the persistent pigment darkening (PPD) method. Dose response experiments of UVA or UV-SSR showed that the preparation with the highest PF-UVA provided a better protection with regard to dermal damage compared to the other formulation. Using an original UVB source to obtain the UVB portion of SSR spectrum, the preparations provided the same protection. This study strikingly illustrates the fact that the photoprotection afforded by two sunscreen formulations having similar SPF values is not equal with regard to dermal damage related to photoaging.

Calculating the dermal flux of chemicals with OELs based on their molecular structure: An attempt to assign the skin notation.

Science.gov (United States)

Kupczewska-Dobecka, Małgorzata; Jakubowski, Marek; Czerczak, Sławomir

2010-09-01

Our objectives included calculating the permeability coefficient and dermal penetration rates (flux value) for 112 chemicals with occupational exposure limits (OELs) according to the LFER (linear free-energy relationship) model developed using published methods. We also attempted to assign skin notations based on each chemical's molecular structure. There are many studies available where formulae for coefficients of permeability from saturated aqueous solutions (K(p)) have been related to physicochemical characteristics of chemicals. The LFER model is based on the solvation equation, which contains five main descriptors predicted from chemical structure: solute excess molar refractivity, dipolarity/polarisability, summation hydrogen bond acidity and basicity, and the McGowan characteristic volume. Descriptor values, available for about 5000 compounds in the Pharma Algorithms Database were used to calculate permeability coefficients. Dermal penetration rate was estimated as a ratio of permeability coefficient and concentration of chemical in saturated aqueous solution. Finally, estimated dermal penetration rates were used to assign the skin notation to chemicals. Defined critical fluxes defined from the literature were recommended as reference values for skin notation. The application of Abraham descriptors predicted from chemical structure and LFER analysis in calculation of permeability coefficients and flux values for chemicals with OELs was successful. Comparison of calculated K(p) values with data obtained earlier from other models showed that LFER predictions were comparable to those obtained by some previously published models, but the differences were much more significant for others. It seems reasonable to conclude that skin should not be characterised as a simple lipophilic barrier alone. Both lipophilic and polar pathways of permeation exist across the stratum corneum. It is feasible to predict skin notation on the basis of the LFER and other published

Detection and characterization of Leishmania in tissues of patients with post kala-azar dermal leishmaniasis using a specific monoclonal antibody

DEFF Research Database (Denmark)

Ismail, A; Kharazmi, A; Permin, H

1997-01-01

Sections from skin lesions and draining lymph nodes of patients with post kala-azar dermal leishmaniasis were examined using an immunoperoxidase method and a monoclonal antibody directed against Leishmania donovani. Parasites were detected in 22 of 25 biopsies (88%). In parallel sections stained...

Assessment of the in vitro dermal irritation potential of cerium, silver, and titanium nanoparticles in a human skin equivalent model

Science.gov (United States)

AbstractDermal exposure to metals may res·ult in irritant contact dermatitis. This study examined the potential of metal nanoparticles to elicit irritant contact dermatitis in a human skin equivalent model (HSEM) derived from epidermal keratinocytes. These cultured cells form a m...

Evaluation of dermal symptoms in hypothyroidism and hyperthyroidism.

Science.gov (United States)

Razi, Ahad; Golforoushan, Farideh; Nejad, Amir Bahrami Shahla Babaee; Goldust, Mohamad

2013-06-01

Many symptoms arise in thyroid diseases. The aim of this study was to evaluate the dermal symptoms in hypothyroidism and hyperthyroidism. In this cross sectional study, 120 patients with hyperthyroidism and 50 patients suffering from hypothyroidism were studied. Cutaneous, hair and nail clinical symptoms were studied and registered in a special questionnaire. Mean age of patients suffering from hypothyroidism and hyperthyroidism were 38.24 +/- 14.45 and 25.86 +/- 14.69 years old. Dry and Coarse/rough skin were the most prevalent manifestations in the skin involvement in hypothyroidism since softness was the most prevalent ones in hyperthyroidism. Fragileness was the most prevalent symptom in patients with nail involvement in hypothyroidism since soft skin was the most prevalent ones in hyperthyroidism. Coarse/rough skin was observed more in patients with hair involvement in hypothyroidism since the most prevalent ones was separation of nail from its bed in hyperthyroidism. High prevalence of skin, hair and nail symptoms in thyroid patients, early diagnosis of the signs may be helpful in premature diagnosis and treatment of thyroid diseases.

Skin permeability and pharmacokinetics of diclofenac epolamine administered by dermal patch in Yorkshire-Landrace pigs

OpenAIRE

Tse S; Powell KD; MacLennan SJ; Moorman AR; Paterson C; Bell RR

2012-01-01

Susanna Tse,1 Kendall D Powell,2 Stephen MacLennan,3 Allan R Moorman,4 Craig Paterson,5 Rosonald R Bell11Pfizer Inc, Groton, CT, USA; 2Tandem Labs, Durham, NC, USA; 3BioCryst Pharmaceuticals Inc, Durham, NC, USA; 4Alta Vetta Pharmaceutical Consulting LLC, Durham, NC, USA; 5Salix Pharmaceuticals Inc, Raleigh, NC, USAPurpose: This study compared the pharmacokinetic profile, and systemic and local absorption of diclofenac, following dermal patch application and oral administration in Yorkshire- ...

Galvanic microparticles increase migration of human dermal fibroblasts in a wound-healing model via reactive oxygen species pathway.

Science.gov (United States)

Tandon, Nina; Cimetta, Elisa; Villasante, Aranzazu; Kupferstein, Nicolette; Southall, Michael D; Fassih, Ali; Xie, Junxia; Sun, Ying; Vunjak-Novakovic, Gordana

2014-01-01

Electrical signals have been implied in many biological mechanisms, including wound healing, which has been associated with transient electrical currents not present in intact skin. One method to generate electrical signals similar to those naturally occurring in wounds is by supplementation of galvanic particles dispersed in a cream or gel. We constructed a three-layered model of skin consisting of human dermal fibroblasts in hydrogel (mimic of dermis), a hydrogel barrier layer (mimic of epidermis) and galvanic microparticles in hydrogel (mimic of a cream containing galvanic particles applied to skin). Using this model, we investigated the effects of the properties and amounts of Cu/Zn galvanic particles on adult human dermal fibroblasts in terms of the speed of wound closing and gene expression. The collected data suggest that the effects on wound closing are due to the ROS-mediated enhancement of fibroblast migration, which is in turn mediated by the BMP/SMAD signaling pathway. These results imply that topical low-grade electric currents via microparticles could enhance wound healing. © 2013 Elsevier Inc. All rights reserved.

Tolerability of NGX-4010, a capsaicin 8% dermal patch, following pretreatment with lidocaine 2.5%/prilocaine 2.5% cream in patients with post-herpetic neuralgia

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Webster Lynn R

2011-12-01

Full Text Available Abstract Background Post-herpetic neuralgia (PHN is a common type of neuropathic pain that can severely affect quality of life. NGX-4010, a capsaicin 8% dermal patch, is a localized treatment that can provide patients with significant pain relief for up to 3 months following a single 60-minute application. The NGX-4010 application can be associated with application-site pain and in previous clinical trials pretreatment with a topical 4% lidocaine anesthetic was used to enhance tolerability. The aim of the current investigation was to evaluate tolerability of NGX-4010 after pretreatment with lidocaine 2.5%/prilocaine 2.5% anesthetic cream. Methods Twenty-four patients with PHN were pretreated with lidocaine 2.5%/prilocaine 2.5% cream for 60 minutes before receiving a single 60-minute application of NGX-4010. Tolerability was assessed by measuring patch application duration, the proportion of patients completing over 90% of the intended treatment duration, application site-related pain using the Numeric Pain Rating Scale (NPRS, and analgesic medication use to relieve such pain. Safety was assessed by monitoring adverse events (AEs and dermal irritation using dermal assessment scores. Results The mean treatment duration of NGX-4010 was 60.2 minutes and all patients completed over 90% of the intended patch application duration. Pain during application was transient. A maximum mean change in NPRS score of +3.0 was observed at 55 minutes post-patch application; pain scores gradually declined to near pre-anesthetic levels (+0.71 within 85 minutes of patch removal. Half of the patients received analgesic medication on the day of treatment; by Day 7, no patients required medication. The most common AEs were application site-related pain, erythema, edema, and pruritus. All patients experienced mild dermal irritation 5 minutes after patch removal, which subsequently decreased; at Day 7, no irritation was evident. The maximum recorded dermal assessment

Evaluation of the effectiveness of the prepectoral breast reconstruction with Braxon dermal matrix: First multicenter European report on 100 cases.

Science.gov (United States)

Vidya, Raghavan; Masià, Jaume; Cawthorn, Simon; Berna, Giorgio; Bozza, Fernando; Gardetto, Alexander; Kołacińska, Agnieszka; Dell'Antonia, Francesco; Tiengo, Cesare; Bassetto, Franco; Caputo, Glenda G; Governa, Maurizio

2017-11-01

We report the outcomes of the European prospective study on prepectoral breast reconstruction using preshaped acellular dermal matrix for complete breast implant coverage. Seventy-nine patients were enrolled between April 2014 and August 2015 all over Europe using a single protocol for patient selection and surgical procedure, according to the Association of Breast Surgery and British Association of Plastic Reconstructive and Aesthetic Surgeons joint guidelines for the use of acellular dermal matrix in breast surgery. The preshaped matrix completely wraps the breast implant, which is placed above the pectoralis major, without detaching the muscle. A total of 100 prepectoral breast reconstructions with complete implant coverage were performed. This series, with mean follow-up of 17.9 months, had two cases of implant loss (2.0%) including one necrosis of the nipple and one wound breakdown (1.0% respectively). No implant rotations were observed. Good cosmetic outcomes were obtained with natural movement of the breasts and softness to the touch; none of the patients reported experiencing pain or reduction in the movements of the pectoralis major muscle postoperatively. The use of preshaped acellular dermal matrix for a complete breast implant coverage in selected patients is safe and gives satisfactory results, both from the aesthetic view point and the low postoperative complication rates. Further studies reporting long-term outcomes are planned. © 2017 Crown copyright. The Breast Journal © 2017 Wiley Periodicals, Inc. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

Dermal, inhalation, and internal exposure to 1,6-HDI and its oligomers in car body repair shop workers and industrial spray painters.

Science.gov (United States)

Pronk, A; Yu, F; Vlaanderen, J; Tielemans, E; Preller, L; Bobeldijk, I; Deddens, J A; Latza, U; Baur, X; Heederik, D

2006-09-01

To study inhalation and dermal exposure to hexamethylene diisocyanate (HDI) and its oligomers as well as personal protection equipment (PPE) use during task performance in conjunction with urinary hexamethylene diamine (HDA) in car body repair shop workers and industrial spray painters. Personal task based inhalation samples (n = 95) were collected from six car body repair shops and five industrial painting companies using impingers with di-n-butylamine (DBA) in toluene. In parallel, dermal exposure was assessed using nitril rubber gloves. Gloves were submerged into DBA in toluene after sampling. Analysis for HDI and its oligomers was performed by LC-MS/MS. Urine samples were collected from 55 workers (n = 291) and analysed for HDA by GC-MS. Inhalation exposure was strongly associated with tasks during which aerosolisation occurs. Dermal exposure occurred during tasks that involve direct handling of paint. In car body repair shops associations were found between detectable dermal exposure and glove use (odds ratio (OR) 0.22, 95% confidence interval (CI) 0.09 to 0.57) and inhalation exposure level (OR 1.34, 95% CI 0.97 to 1.84 for a 10-fold increase). HDA in urine could be demonstrated in 36% and 10% of car body repair shop workers and industrial painting company workers respectively. In car body repair shops, the frequency of detectable HDA was significantly elevated at the end of the working day (OR 2.13, 95% CI 1.07 to 4.22 for 3-6 pm v 0-8 am). In both branches HDA was detected in urine of approximately 25% of the spray painters. In addition HDA was detected in urine of a large proportion of non-spray painters in car body repair shops. Although (spray) painting with lacquers containing isocyanate hardeners results in the highest external exposures to HDI and oligomers, workers that do not perform paint related tasks may also receive a considerable internal dose.

EFSA Panel on Plant Protection Products and their Residues (PPR); EFSA Scientific Opinion on the science behind the revision of the guidance document on dermal absorption

DEFF Research Database (Denmark)

Petersen, Annette

will be finalised and published only after adoption and publication of this opinion. This opinion has been developed after a public consultation of EFSA on the current guidance document and an outsourced project carried out by the UK Chemicals Regulation Directorate (CRD, 2010). It is not intended...... that have an impact on absorption, a description of important elements in the design of experimental studies and an analysis of available data on dermal absorption of PPPs. The PPR Panel concludes that assessment of dermal absorption in the absence of specific studies can be performed based on default...

Diagnosis and treatment of a dermal malignant melanoma in an African lion (Panthera leo).

Science.gov (United States)

Steeil, James C; Schumacher, Juergen; Baine, Katherine; Ramsay, Edward C; Sura, Patricia; Hodshon, Rebecca; Donnell, Robert L; Lee, Nathan D

2013-09-01

A 13-yr-old intact male African lion (Panthera leo) presented with a 4-mo history of left maxillary lip swelling. On physical examination, a 10-cm-diameter, ulcerated, round, firm, and pigmented mass at the level of the left maxillary canine tooth was noticed. All other organ systems examined were within normal limits. Multiple biopsies of the mass were collected and fixed in 10% neutral buffered formalin. Histopathologic evaluation of the biopsies revealed a malignant dermal melanoma. Hematologic and plasma biochemical parameters were within normal reference ranges. Thoracic radiographs taken 3 days following initial presentation showed no evidence of metastasis of the tumor. Computed tomography of the skull and neck was performed to evaluate local tumor invasion and to plan for hypofractionated radiation therapy. Therapy included four weekly treatments of 8 gray external-beam hypofractionated radiation and four bimonthly immunotherapy treatments. Following this treatment regime, the tumor size was reduced by 50%, and surgical excision was performed. No major side effects associated with radiation or immunotherapy were seen. Six months after diagnosis, hematologic and plasma biochemical parameters were within normal limits, thoracic radiographs showed no evidence of metastasis, and the lion showed no clinical signs of disease. The lion will continue to receive immunotherapy every 6 mo for the rest of its life. To the authors' knowledge, this is the first report of a successful treatment of a malignant dermal melanoma with external-beam hypofractionated radiation, immunotherapy, and surgical excision in an African lion.

The protective effects of fucosterol against skin damage in UVB-irradiated human dermal fibroblasts.

Science.gov (United States)

Hwang, Eunson; Park, Sang-Yong; Sun, Zheng-wang; Shin, Heon-Sub; Lee, Don-Gil; Yi, Tae Hoo

2014-06-01

Exposure to ultraviolet (UV) light causes matrix metalloproteinase (MMP) overexpression and extracellular matrix depletion, leading to skin photoaging. The activation of MMP is related to increased interlukin-6 (IL-6) and type I procollagen production, which is regulated by transforming growth factor-β1 (TGF-β1). Activator protein-1 (AP-1) activation induces MMP-1 production and reduces type I procollagen secretion. Fucosterol, which is extracted and purified from the brown algae Hizikia fusiformis, is a phytosterol. We assessed the effects of fucosterol on photodamage and investigated its molecular mechanism of action in UVB-irradiated normal human dermal fibroblasts by using enzyme-linked immunosorbent assay, Western blot analysis, and reverse transcription-polymerase chain reaction. Our results showed that fucosterol significantly decreased the UVB-induced expression of MMP-1, IL-6, p-c-Jun, and p-c-Fos. Additionally, fucosterol markedly increased the UVB-induced production of type I procollagen and TGF-β1. Our results indicate that fucosterol regulates MMP-1 and type I procollagen expression by modulating AP-1 and TGF-β1 signaling and that MMP-1 activation is correlated with IL-6. These data suggest that fucosterol is a promising botanical agent to protect against skin photodamage.

Investigation of acute dermal irritation/corrosion, acute inhalation toxicity and cytotoxicity tests for Nanobiocide®

Directory of Open Access Journals (Sweden)

Mansour Hemmati

2016-07-01

Full Text Available Objective(s: Nanomaterials, especially silver Nanoparticles (Ag-NPs, are employed in an increasing number of commercial products. This has led to an ever growing exposure of human beings to this substance. The first purpose of the Nano Committee of Food and Drug Administration of The Islamic Republic of Iran (IFDA is developing guidelines to assess and approve commercial nano-health products for their safety of human applications. Nanobiocide® as a commercial product of stable colloid including 2000 ppm Ag-NPs for surface antimicrobial applications was investigated according to IFDA guidelines in the approval process. Methods: The first fabrication and characterization method of the product were determined. The human exposure to Nanobiocide® were studied by cytotoxicity assay, dermal irritation and inhalation toxicity assay based on the standard assay. Results: According to cytotoxicity assay by MTT method the concentration-dependent of cell viability was reduced and Inhibitory concentration-50 was about 1160 ppm. The Draize dermal irritation scoring system (DDIS showed no irritation to the skin of rabbits. No sign of gross toxicity, adverse pharmacological effect, or abnormal behavior based on inhalation toxicity was observed. Conclusions: The consideration of toxicity of Nanobiocide® is one of the major key for medical application. The results obtained revealed that the Nanobiocide® may be safe using in domestic and veterinary applications.

Engraftment potential of dermal fibroblasts following in vivo myogenic conversion in immunocompetent dystrophic skeletal muscle

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Lindsey A Muir

2014-01-01

Full Text Available Autologous dermal fibroblasts (dFbs are promising candidates for enhancing muscle regeneration in Duchenne muscular dystrophy (DMD due to their ease of isolation, immunological compatibility, and greater proliferative potential than DMD satellite cells. We previously showed that mouse fibroblasts, after MyoD-mediated myogenic reprogramming in vivo, engraft in skeletal muscle and supply dystrophin. Assessing the therapeutic utility of this system requires optimization of conversion and transplantation conditions and quantitation of engraftment so that these parameters can be correlated with possible functional improvements. Here, we derived dFbs from transgenic mice carrying mini-dystrophin, transduced them by lentivirus carrying tamoxifen-inducible MyoD, and characterized their myogenic and engraftment potential. After cell transplantation into the muscles of immunocompetent dystrophic mdx4cv mice, tamoxifen treatment drove myogenic conversion and fusion into myofibers that expressed high levels of mini-dystrophin. Injecting 50,000 cells/µl (1 × 106 total cells resulted in a peak of ∼600 mini-dystrophin positive myofibers in tibialis anterior muscle single cross-sections. However, extensor digitorum longus muscles with up to 30% regional engraftment showed no functional improvements; similar limitations were obtained with whole muscle mononuclear cells. Despite the current lack of physiological improvement, this study suggests a viable initial strategy for using a patient-accessible dermal cell population to enhance skeletal muscle regeneration in DMD.

In vitro dermal and epidermal cellular response to titanium alloy implants fabricated with electron beam melting.

Science.gov (United States)

Springer, Jessica Collins; Harrysson, Ola L A; Marcellin-Little, Denis J; Bernacki, Susan H

2014-10-01

Transdermal osseointegrated prostheses (TOPs) are emerging as an alternative to socket prostheses. Electron beam melting (EBM) is a promising additive manufacturing technology for manufacture of custom, freeform titanium alloy (Ti6Al4V) implants. Skin ongrowth for infection resistance and mechanical stability are critically important to the success of TOP, which can be influenced by material composition and surface characteristics. We assessed viability and proliferation of normal human epidermal keratinocytes (NHEK) and normal human dermal fibroblasts (NHDF) on several Ti6Al4V surfaces: solid polished commercial, solid polished EBM, solid unpolished EBM and porous unpolished EBM. Cell proliferation was evaluated at days 2 and 7 using alamarBlue(®) and cell viability was analyzed with a fluorescence-based live-dead assay after 1 week. NHDF and NHEK were viable and proliferated on all Ti6Al4V surfaces. NHDF proliferation was highest on commercial and EBM polished surfaces. NHEK was highest on commercial polished surfaces. All EBM Ti6Al4V discs exhibited an acceptable biocompatibility profile compared to solid Ti6Al4V discs from a commercial source for dermal and epidermal cells. EBM may be considered as an option for fabrication of custom transdermal implants. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

Enhanced dermal delivery of diflucortolone valerate using lecithin/chitosan nanoparticles: in-vitro and in-vivo evaluations

Science.gov (United States)

Özcan, İpek; Azizoğlu, Erkan; Şenyiğit, Taner; Özyazıcı, Mine; Özer, Özgen

2013-01-01

The objective of this study was to prepare a suitable formulation for dermal delivery of diflucortolone valerate (DFV) that would maintain the localization in skin layers without any penetration and to optimize efficiency of DFV. Drug-loaded lecithin/chitosan nanoparticles with high entrapment efficiency (86.8%), were successfully prepared by ionic interaction technique. Sustained release of DFV was achieved without any initial burst release. Nanoparticles were also incorporated into chitosan gel at different ratios for preparing a more suitable formulation for topical drug delivery with adequate viscosity. In ex-vivo permeation studies, nanoparticles increased the accumulation of DFV especially in the stratum corneum + epidermis of rat skin without any significant permeation. Retention of DFV from nanoparticle in chitosan gel formulation (0.01%) was twofold higher than commercial cream, although it contained ten times less DFV. Nanoparticles in gel formulations produced significantly higher edema inhibition in rats compared with commercial cream in in-vivo studies. Skin blanching assay using a chromameter showed vasoconstriction similar to that of the commercial product. There were no barrier function changes upon application of nanoparticles. In-vitro and in-vivo results demonstrated that lecithin/chitosan nanoparticles in chitosan gel may be a promising carrier for dermal delivery of DFV in various skin disorders. PMID:23390364

Dermal absorption and disposition of methoxy (ME), ethoxy- (EE), and butoxy[U-14C]ethanol (BE)

International Nuclear Information System (INIS)

Sabourin, P.J.; Medinsky, M.A.; Thurmond, F.; Henderson, R.F.; Birnbaum, L.S.

1990-01-01

The glycol ethers (GEs) demonstrate testicular and hemopoietic toxicity. The object of this study was to determine the effect of dose (500-3,000 μmoles/kg) on the disposition of dermally applied 14 C-labeled GEs by male F344 rats. Following application of [ 14 C]GEs in acetone (90 μL), the rats were immediately placed in metabolism cages for collection of excreta and exhaled air. No significant dose related trends in absorption (16-38% of applied dose) or disposition of 14 C were noted for any of the GEs. As the chain length of the GE increased, more of the dose was excreted in the urine as the alkoxy acetic acid (AA) and less of the dose entered the one carbon pool following dealkylation, as reflected by 14 C 2 exhaled. AA was the major metabolite of all 3 GEs except for ME at high doses where an unidentified metabolite represented 53% of the urinary metabolites. Ethylene glycol (EG) represented about 10-15% of the urinary metabolites for all 3 GEs at all doses. GEs administered in drinking water were metabolized more to EG and CO 2 , and less to AA in comparison to dermal studies, most likely due to the slower dose rate in drinking water studies

Th17 cell-mediated immune responses promote mast cell proliferation by triggering stem cell factor in keratinocytes

International Nuclear Information System (INIS)

Cho, Kyung-Ah; Park, Minhwa; Kim, Yu-Hee; Woo, So-Youn

2017-01-01

Although mast cells are traditionally thought to function as effector cells in allergic responses, they have increasingly been recognized as important regulators of various immune responses. Mast cells mature locally; thus, tissue-specific influences are important for promoting mast cell accumulation and survival in the skin and the gastrointestinal tract. In this study, we determined the effects of keratinocytes on mast cell accumulation during Th17-mediated skin inflammation. We observed increases in dermal mast cells in imiquimod-induced psoriatic dermatitis in mice accompanied by the expression of epidermal stem cell factor (SCF), a critical mast cell growth factor. Similar to mouse epidermal keratinocytes, SCF was highly expressed in the human HaCaT keratinocyte cell line following stimulation with IL−17. Further, keratinocytes promoted mast cell proliferation following stimulation with IL−17 in vitro. However, the effects of keratinocytes on mast cells were significantly diminished in the presence of anti−CD117 (stem cell factor receptor) blocking antibodies. Taken together, our results revealed that the Th17-mediated inflammatory environment promotes mast cell accumulation through keratinocyte-derived SCF. - Highlights: • Psoriasis-like skin inflammation increase dermal mast cells. • Keratinocyte produce stem cell factor in psoriasis-like skin inflammation. • Keratinocyte promote mast cell proliferation by stem cell factor dependent manner

Comparative developmental dermal toxicity and mutagenicity of carbazole and benzo[a]carbazole

International Nuclear Information System (INIS)

Dutson, S.M.; Booth, G.M.; Seegmiller, R.E.; Schaalje, G.B.; Castle, R.N.

1997-01-01

The objectives of this study were (1) to determine the developmental toxicity of carbazole and benzo[a]carbazole following daily dermal administration to female Sprague-Dawley rats on days 0 through 20 of gestation and (2) to determine the mutagenicity of these two compounds using a modified version of the Ames assay. These chemicals are of concern because they are found in a variety of environmental matrices including crude oil mixtures. No signs of maternal or developmental toxicity were considered to be related to dermal administration of carbazole at does of 2.5, 25.0, and 250.0 mg/kg. Signs of maternal toxicity considered to be related to administration of benzo[a]carbazole included significantly decreased body-weight gain and decreased absolute-food consumption at a dose of 250.0 mg/kg. Signs of developmental toxicity considered to be related to administration of benzo[a]carbazole included significantly decreased number of total (live and dead combined) and live pups on lactation day 0 as well as significantly decreased average pup weight on lactation days 0 and 4 at a dose of 250.0 mg/kg. Because developmental toxicity following benzo[a]carbazole treatment was observed only at a dose at which maternal toxicity was observed, it is likely that the effects on the offspring are secondary to the treatment effects on the dam. Evidence of toxic effects with benzo[a]carbazole in the absence of effects with carbazole suggests that the substituted benzene ring enhances the biological activity of this compound. Carbazole was nonmutagenic with or without S-9 activation, whereas benzo[a]carbazole showed a clear dose-response with S-9 activation. Without S-9 activation, benzo[a]carbazole was nonmutagenic. Apparently benzo[a]carbazole must be enzymatically activated in order to be mutagenic

Dermal Exposure Associated with Occupational End Use of Pesticides and the Role of Protective Measures

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Ewan MacFarlane

2013-09-01

Conclusions: Although international and national efforts to reduce pesticide exposure through regulatory means should continue, it is difficult in the agricultural sector to implement engineering or system controls. It is clear that use of PPE does reduce dermal pesticide exposure but compliance among the majority of occupationally exposed pesticide end users appears to be poor. More research is needed on higher-order controls to reduce pesticide exposure and to understand the reasons for poor compliance with PPE and identify effective training methods.

TCDD induces dermal accumulation of keratinocyte-derived matrix metalloproteinase-10 in an organotypic model of human skin

Energy Technology Data Exchange (ETDEWEB)

De Abrew, K. Nadira [Molecular and Environmental Toxicology Center, University of Wisconsin—Madison, Madison, WI 53706 (United States); Thomas-Virnig, Christina L.; Rasmussen, Cathy A. [Department of Pathology, University of Wisconsin—Madison, Madison, WI 53706 (United States); Bolterstein, Elyse A. [Molecular and Environmental Toxicology Center, University of Wisconsin—Madison, Madison, WI 53706 (United States); Schlosser, Sandy J. [Department of Pathology, University of Wisconsin—Madison, Madison, WI 53706 (United States); Allen-Hoffmann, B. Lynn, E-mail: blallenh@wisc.edu [Molecular and Environmental Toxicology Center, University of Wisconsin—Madison, Madison, WI 53706 (United States); Department of Pathology, University of Wisconsin—Madison, Madison, WI 53706 (United States)

2014-05-01

The epidermis of skin is the first line of defense against the environment. A three dimensional model of human skin was used to investigate tissue-specific phenotypes induced by the environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Continuous treatment of organotypic cultures of human keratinocytes with TCDD resulted in intracellular spaces between keratinocytes of the basal and immediately suprabasal layers as well as thinning of the basement membrane, in addition to the previously reported hyperkeratinization. These tissue remodeling events were preceded temporally by changes in expression of the extracellular matrix degrading enzyme, matrix metalloproteinase-10 (MMP-10). In organotypic cultures MMP-10 mRNA and protein were highly induced following TCDD treatment. Q-PCR and immunoblot results from TCDD-treated monolayer cultures, as well as indirect immunofluorescence and immunoblot analysis of TCDD-treated organotypic cultures, showed that MMP-10 was specifically contributed by the epidermal keratinocytes but not the dermal fibroblasts. Keratinocyte-derived MMP-10 protein accumulated over time in the dermal compartment of organotypic cultures. TCDD-induced epidermal phenotypes in organotypic cultures were attenuated by the keratinocyte-specific expression of tissue inhibitor of metalloproteinase-1, a known inhibitor of MMP-10. These studies suggest that MMP-10 and possibly other MMP-10-activated MMPs are responsible for the phenotypes exhibited in the basement membrane, the basal keratinocyte layer, and the cornified layer of TCDD-treated organotypic cultures. Our studies reveal a novel mechanism by which the epithelial–stromal microenvironment is altered in a tissue-specific manner thereby inducing structural and functional pathology in the interfollicular epidermis of human skin. - Highlights: • TCDD causes hyperkeratosis and basement membrane changes in a model of human skin. • TCDD induces MMP-10 expression in organotypic cultures

Original technique for penile girth augmentation through porcine dermal acellular grafts: results in a 69-patient series.

Science.gov (United States)

Alei, Giovanni; Letizia, Piero; Ricottilli, Francesco; Simone, Pierfranco; Alei, Lavinia; Massoni, Francesco; Ricci, Serafino

2012-07-01

Although different techniques for augmentation phalloplasty have been reported in the medical literature, this issue is still highly controversial, and none of the proposed procedures has been unanimously approved. The aim of this study is to describe an innovative surgical technique for penile girth augmentation with porcine dermal acellular grafts, through a small transverse incision at the penile base, along the penopubic junction. Between 2000 and 2009, 104 patients were referred to our institution for penile enhancement. After a preoperative psychosexual consultation and a general medical assessment, 69 patients were deemed suitable good candidates for surgery. The average penis circumference was measured at the mid-length of the penis and was 8.1 cm (5.4-10.7 cm) and 10.8 cm (6.5-15.8 cm) during flaccidity and erection, respectively. All patients received penile augmentation with porcine dermal acellular grafts. Results evaluation of an innovative technique for penile girth augmentation through exogenous porcine grafts and small penobubic incision. Postoperative measurements were performed at 6 and 12 months. At the 1-year follow-up, the average penis circumference was 11.3 cm (8.2-13.2 cm, 3.1 cm mean increase) during flaccidity and 13.2 cm (8.8-14.5 cm, 2.4 cm mean increase) during erection. No major complications occurred in the series. Minor complications were resolved with conservative treatment within 3 weeks. Sexual activity was resumed from 1 to 2 months after surgery. The psychosexual impact of the operation was beneficial in the majority of cases. Penile girth enlargement with acellular dermal matrix grafts has several advantages over augmentation with autogenous dermis-fat grafts: the elimination of donor site morbidity and a significantly shorter operation time. With this approach, through a short dorsal incision at the base of the penis, the scar is concealed in a crease covered by pubic hair and thus hardly visible. © 2012

Predicting dermal penetration for ToxCast chemicals using in silico estimates for diffusion in combination with physiologically based pharmacokinetic (PBPK) modeling.

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Predicting dermal penetration for ToxCast chemicals using in silico estimates for diffusion in combination with physiologically based pharmacokinetic (PBPK) modeling.Evans, M.V., Sawyer, M.E., Isaacs, K.K, and Wambaugh, J.With the development of efficient high-throughput (HT) in ...

STAT5 Activation in the Dermal Papilla Is Important for Hair Follicle Growth Phase Induction.

Science.gov (United States)

Legrand, Julien M D; Roy, Edwige; Ellis, Jonathan J; Francois, Mathias; Brooks, Andrew J; Khosrotehrani, Kiarash

2016-09-01

Hair follicles are skin appendages that undergo periods of growth (anagen), regression (catagen), and rest (telogen) regulated by their mesenchymal component, the dermal papilla (DP). On the basis of the reports of its specific expression in the DP, we investigated signal transducer and activator of transcription (STAT5) activation during hair development and cycling. STAT5 activation in the DP began in late catagen, reaching a peak in early anagen before disappearing for the rest of the cycle. This was confirmed by the expression profile of suppressor of cytokine signaling 2, a STAT5 target in the DP. This pattern of expression starts after the first postnatal hair cycle. Quantification of hair cycling using the Flash canonical Wnt signaling in vivo bioluminescence reporter found that conditional knockout of STAT5A/B in the DP targeted through Cre-recombinase under the control of the Sox18 promoter resulted in delayed anagen entry compared with control. Microarray analysis of STAT5 deletion versus control revealed key changes in tumor necrosis factor-α, Wnt, and fibroblast growth factor ligands, known for their role in inducing anagen entry. We conclude that STAT5 activation acts as a mesenchymal switch to trigger natural anagen entry in postdevelopmental hair follicle cycling. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Resveratrol, 4' Acetoxy Resveratrol, R-equol, Racemic Equol or S-equol as Cosmeceuticals to Improve Dermal Health.

Science.gov (United States)

Lephart, Edwin D

2017-06-03

Phytochemicals are botanical compounds used in dermatology applications as cosmeceuticals to improve skin health. Resveratrol and equol are two of the best-known polyphenolic or phytoestrogens having similar chemical structures and some overlapping biological functions to 17β-estradiol. Human skin gene expression was reviewed for 28 different biomarkers when resveratrol, 4' acetoxy resveratrol (4AR), R -equol, racemic equol or S -equol were tested. Sirtuin 1 activator (SIRT 1) was stimulated by resveratrol and 4AR only. Resveratrol, R -equol and racemic equol were effective on the aging biomarkers proliferating cell nuclear factor (PCNA), nerve growth factor (NGF), 5α-reductase and the calcium binding proteins S100 A8 and A9. Racemic equol and 4AR displayed among the highest levels for the collagens, elastin and tissue inhibitor of the matrix metalloproteinase 1 (TIMP 1). S -equol displayed the lowest level of effectiveness compared to the other compounds. The 4AR analog was more effective compared to resveratrol by 1.6-fold. R -equol and racemic equol were almost equal in potency displaying greater inhibition vs. resveratrol or its 4' analog for the matrix metalloproteinases (MMPs), but among the inflammatory biomarkers, resveratrol, 4AR, R -equol and racemic equol displayed high inhibition. Thus, these cosmeceuticals display promise to improve dermal health; however, further study is warranted to understand how phytochemicals protect/enhance the skin.

Long-term scar quality after hydrosurgical versus conventional debridement of deep dermal burns (HyCon trial): study protocol for a randomized controlled trial.

Science.gov (United States)

Legemate, Catherine M; Goei, Harold; Middelkoop, Esther; Oen, Irma M M H; Nijhuis, Tim H J; Kwa, Kelly A A; van Zuijlen, Paul P M; Beerthuizen, Gerard I J M; Nieuwenhuis, Marianne K; van Baar, Margriet E; van der Vlies, Cornelis H

2018-04-19

Deep dermal burns require tangential excision of non-viable tissue and skin grafting to improve wound healing and burn-scar quality. Tangential excision is conventionally performed with a knife, but during the last decade hydrosurgery has become popular as a new tool for tangential excision. Hydrosurgery is generally thought to be a more precise and controlled manner of burn debridement leading to preservation of viable tissue and, therefore, better scar quality. Although scar quality is considered to be one of the most important outcomes in burn surgery today, no randomized controlled study has compared the effect of these two common treatment modalities with scar quality as a primary outcome. The aim of this study is, therefore, to compare long-term scar quality after hydrosurgical versus conventional tangential excision in deep dermal burns. A multicenter, randomized, intra-patient, controlled trial will be conducted in the Dutch burn centers of Rotterdam, Beverwijk, and Groningen. All patients with deep dermal burns that require excision and grafting are eligible. Exclusion criteria are: a burn wound burned > 30%, full-thickness burns, chemical or electrical burns, infected wounds (clinical symptoms in combination with positive wound swabs), insufficient knowledge of the Dutch or English language, patients that are unlikely to comply with requirements of the study protocol and follow-up, and patients who are (temporarily) incompetent because of sedation and/or intubation. A total of 137 patients will be included. Comparable wound areas A and B will be appointed, randomized and either excised conventionally with a knife or with the hydrosurgery system. The primary outcome is scar quality measured by the observer score of the Patient and Observer Scar Assessment Scale (POSAS); a subjective scar-assessment instrument, consisting of two separate six-item scales (observer and patient) that are both scored on a 10-point rating scale. This study will contribute to

Dermal, inhalation, and internal exposure to 1,6‐HDI and its oligomers in car body repair shop workers and industrial spray painters

Science.gov (United States)

Pronk, A; Yu, F; Vlaanderen, J; Tielemans, E; Preller, L; Bobeldijk, I; Deddens, J A; Latza, U; Baur, X; Heederik, D

2006-01-01

Objectives To study inhalation and dermal exposure to hexamethylene diisocyanate (HDI) and its oligomers as well as personal protection equipment (PPE) use during task performance in conjunction with urinary hexamethylene diamine (HDA) in car body repair shop workers and industrial spray painters. Methods Personal task based inhalation samples (n = 95) were collected from six car body repair shops and five industrial painting companies using impingers with di‐n‐butylamine (DBA) in toluene. In parallel, dermal exposure was assessed using nitril rubber gloves. Gloves were submerged into DBA in toluene after sampling. Analysis for HDI and its oligomers was performed by LC‐MS/MS. Urine samples were collected from 55 workers (n = 291) and analysed for HDA by GC‐MS. Results Inhalation exposure was strongly associated with tasks during which aerosolisation occurs. Dermal exposure occurred during tasks that involve direct handling of paint. In car body repair shops associations were found between detectable dermal exposure and glove use (odds ratio (OR) 0.22, 95% confidence interval (CI) 0.09 to 0.57) and inhalation exposure level (OR 1.34, 95% CI 0.97 to 1.84 for a 10‐fold increase). HDA in urine could be demonstrated in 36% and 10% of car body repair shop workers and industrial painting company workers respectively. In car body repair shops, the frequency of detectable HDA was significantly elevated at the end of the working day (OR 2.13, 95% CI 1.07 to 4.22 for 3–6 pm v 0–8 am). In both branches HDA was detected in urine of ∼25% of the spray painters. In addition HDA was detected in urine of a large proportion of non‐spray painters in car body repair shops. Conclusion Although (spray) painting with lacquers containing isocyanate hardeners results in the highest external exposures to HDI and oligomers, workers that do not perform paint related tasks may also receive a considerable internal dose. PMID:16728504

Synthetic ligands of the elastin receptor induce elastogenesis in human dermal fibroblasts via activation of their IGF-1 receptors.

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Qa'aty, Nour; Vincent, Matthew; Wang, Yanting; Wang, Andrew; Mitts, Thomas F; Hinek, Aleksander

2015-12-01

We have previously reported that a mixture of peptides obtained after chemical or enzymatic degradation of bovine elastin, induced new elastogenesis in human skin. Now, we investigated the elastogenic potential of synthetic peptides mimicking the elastin-derived, VGVAPG sequence, IGVAPG sequence that we found in the rice bran, and a similar peptide, VGVTAG that we identified in the IGF-1-binding protein-1 (IGFBP-1). We now demonstrate that treatment with each of these xGVxxG peptides (recognizable by the anti-elastin antibody), up-regulated the levels of elastin-encoding mRNA, tropoelastin protein, and the deposition of new elastic fibers in cultures of human dermal fibroblasts and in cultured explants of human skin. Importantly, we found that such induction of new elastogenesis may involve two parallel signaling pathways triggered after activation of IGF-1 receptor. In the first one, the xGVxxG peptides interact with the cell surface elastin receptor, thereby causing the downstream activation of the c-Src kinase and a consequent cross-activation of the adjacent IGF-1R, even in the absence of its principal ligand. In the second pathway their hydrophobic association with the N-terminal domain (VGVTAG) of the serum-derived IGFBP-1 induces conformational changes of this IGF-1 chaperone allowing for the release of its cargo and a consequent ligand-specific phosphorylation of IGF-1R. We present a novel, clinically relevant mechanism in which products of partial degradation of dermal elastin may stimulate production of new elastic fibers by dermal fibroblasts. Our findings particularly encourage the use of biologically safe synthetic xGVxxG peptides for regeneration of the injured or aged human skin. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Large pore dermal microdialysis and liquid chromatography-tandem mass spectroscopy shotgun proteomic analysis: a feasibility study.

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Petersen, Lars J; Sørensen, Mette A; Codrea, Marius C; Zacho, Helle D; Bendixen, Emøke

2013-11-01

The purpose of the present pilot study was to investigate the feasibility of combining large pore dermal microdialysis with shotgun proteomic analysis in human skin. Dialysate was recovered from human skin by 2000 kDa microdialysis membranes from one subject at three different phases of the study; trauma due to implantation of the dialysis device, a post implantation steady-state period, and after induction of vasodilatation and plasma extravasation. For shotgun proteomics, the proteins were extracted and digested with trypsin. Peptides were separated by capillary and nanoflow HPLC systems, followed by tandem mass spectrometry (MS/MS) on a Quadrupole-TOF hybrid instrument. The MS/MS spectra were merged and mapped to a human target protein database to achieve peptide identification and protein inference. Results showed variation in protein amounts and profiles for each of the different sampling phases. The total protein concentration was 1.7, 0.6, and 1.3 mg/mL during the three phases, respectively. A total of 158 different proteins were identified. Immunoglobulins and the major classes of plasma proteins, including proteases, coagulation factors, apolipoproteins, albumins, and complement factors, make up the major load of proteins in all three test conditions. Shotgun proteomics allowed the identification of more than 150 proteins in microdialysis samples from human skin. This highlights the opportunities of LC-MS/MS to study the complex molecular interactions in the skin. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Redox-active cerium oxide nanoparticles protect human dermal fibroblasts from PQ-induced damage

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Claudia von Montfort

2015-04-01

Full Text Available Recently, it has been published that cerium (Ce oxide nanoparticles (CNP; nanoceria are able to downregulate tumor invasion in cancer cell lines. Redox-active CNP exhibit both selective pro-oxidative and antioxidative properties, the first being responsible for impairment of tumor growth and invasion. A non-toxic and even protective effect of CNP in human dermal fibroblasts (HDF has already been observed. However, the effect on important parameters such as cell death, proliferation and redox state of the cells needs further clarification. Here, we present that nanoceria prevent HDF from reactive oxygen species (ROS-induced cell death and stimulate proliferation due to the antioxidative property of these particles.

The pathogenesis of post kala-azar dermal leishmaniasis from the field to the molecule: does ultraviolet light (UVB) radiation play a role?

DEFF Research Database (Denmark)

Ismail, A; Khalil, E A G; Musa, A M

2006-01-01

Post kala-azar dermal leishmaniasis (PKDL) is a dermatosis caused by persistence of Leishmania donovani parasites in the skin following apparently successful treatment of visceral leishmaniasis. The distribution of PKDL lesions in Sudanese patients often mirrors the clothing habits of those...

MicroRNA-99 family targets AKT/mTOR signaling pathway in dermal wound healing.

Science.gov (United States)

Jin, Yi; Tymen, Stéphanie D; Chen, Dan; Fang, Zong Juan; Zhao, Yan; Dragas, Dragan; Dai, Yang; Marucha, Phillip T; Zhou, Xiaofeng

2013-01-01

Recent studies suggest that microRNAs play important roles in dermal wound healing and microRNA deregulation has been linked with impaired wound repair. Here, using a mouse experimental wound healing model, we identified a panel of 63 differentially expressed microRNAs during dermal wound healing, including members of miR-99 family (miR-99a, miR-99b, miR-100). We further demonstrated that miR-99 family members regulate cell proliferation, cell migration, and AKT/mTOR signaling. Combined experimental and bioinformatics analyses revealed that miR-99 family members regulate AKT/mTOR signaling by targeting multiple genes, including known target genes (e.g., IGF1R, mTOR) and a new target (AKT1). The effects of miR-99 family members on the expression of IGF1R, mTOR and AKT1 were validated at both the mRNA and protein levels. Two adjacent miR-99 family targeting sites were identified in the 3'-UTR of the AKT1 mRNA. The direct interaction of miR-100 with these targeting sites was confirmed using luciferase reporter assays. The microRNA-100-directed recruitment of AKT1 mRNA to the RNAi-induced silencing complex (RISC) was confirmed by a ribonucleoprotein-IP assay. In summary, we identified a panel of differentially expressed microRNAs which may play important roles in wound healing. We provide evidence that miR-99 family members contribute to wound healing by regulating the AKT/mTOR signaling.

Antibacterial Effect of Autologous Platelet-Rich Gel Derived from Subjects with Diabetic Dermal Ulcers In Vitro

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Lihong Chen

2013-01-01

Full Text Available Background. Autologous platelet-rich gel (APG is an effective method to improve ulcer healing. However, the mechanisms are not clear. This study aimed to investigate the antibacterial effect of APG in vitro. Methods. Platelet-rich plasma (PRP, platelet-poor plasma (PPP and APG were prepared from whole blood of sixteen diabetic patients with dermal ulcers. Antibacterial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were evaluated by bacteriostasis assay of APG, PRP, and APG-APO (APG combined with apocynin, with phosphate-buffered saline (PBS and PPP as the control group. Results. (1 Compared to the PBS and PPP, the APG and APG-APO groups showed strong antibacterial activity against Staphylococcus aureus. There was no significant difference (P>0.05 between APG and APG-APO. (2 Compared to PBS, APG, APG-APO, and PRP showed obvious antibacterial effects against Escherichia coli and Pseudomonas aeruginosa. No significant difference (P>0.05 was revealed among the three groups. Compared to the PPP group, they did not show antibacterial effect against Escherichia coli and Pseudomonas aeruginosa (P>0.05. Conclusions. APG has antibacterial effect against Staphylococcus aureus mediated by platelet activation in the diabetic patients with dermal ulcer, and does not present obvious antibacterial effect against Escherichia coli or Pseudomonas aeruginosa. Combination of APG and antibiotics may have synergistic antibacterial effect.

Effects of plant sterols derived from Aloe vera gel on human dermal fibroblasts in vitro and on skin condition in Japanese women

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Tanaka M

2015-02-01

Full Text Available Miyuki Tanaka,1 Eriko Misawa,1 Koji Yamauchi,1 Fumiaki Abe,1 Chiaki Ishizaki2 1Functional Food Research Department, Food Science and Technology Institute, Morinaga Milk Industry Co, Ltd, Zama, Kanagawa, 2Ebisu Skin Research Center, Inforward, Inc., Tokyo, Japan Background: Aloe is known for its topical use for treating wounds and burns. Many previous studies reported the healing effects of Aloe vera. However, there are few clinical studies on the effect of orally administered A. vera gel on the skin. Aloe sterols are a type of plant sterols that have the capability to regulate the metabolism of glucose and lipids. In a recent study, we confirmed that ingested Aloe sterols reached the peripheral tissues through the bloodstream. However, their influence on dermal fibroblasts has not been investigated. Methods: First, we investigated the capability of Aloe sterols (cycloartenol and lophenol to stimulate human dermal fibroblasts in vitro. Then, we investigated the effect of intake of Aloe vera gel powder (AVGP containing 40 µg Aloe sterols on the skin conditions in Japanese women with dry skin in a randomized, double-blind, placebo-controlled trial. Results: After cocultivation with Aloe sterols, the production of collagen and hyaluronic acid increased by approximately two-fold and 1.5-fold, and gene expression levels of these enzymes responsible for their synthesis were also observed in human dermal fibroblasts. An increase in arm skin hydration was observed at 8 weeks in the AVGP group, whereas a slight decrease in arm skin hydration was noted in the placebo group. However, there was no statistical difference between AVGP and placebo groups in skin moisture. In subgroup analysis, the change in the mean wrinkle depth was significantly lower in the AVGP group than in the control group. In addition, percent body fat after 8 weeks was significantly lower in the AVGP group. No AVGP intake-dependent harmful phenomenon was observed during the intake

Nested PCR Assay for Detection of Leishmania donovani in Slit Aspirates from Post-Kala-Azar Dermal Leishmaniasis Lesions

Science.gov (United States)

Sreenivas, Gannavaram; Ansari, N. A.; Kataria, Joginder; Salotra, Poonam

2004-01-01

A nested PCR assay to detect parasite DNA in slit aspirates from skin lesions of patients with post-kala-azar dermal lesihmaniasis (PKDL) is described. PCR results were positive in 27 of 29 (93%) samples by nested PCR assay, while only 20 of 29 (69%) were positive in a primary PCR assay. The nested PCR assay allowed reliable diagnosis of PKDL in a noninvasive manner. PMID:15071047

Nested PCR Assay for Detection of Leishmania donovani in Slit Aspirates from Post-Kala-Azar Dermal Leishmaniasis Lesions

OpenAIRE

Sreenivas, Gannavaram; Ansari, N. A.; Kataria, Joginder; Salotra, Poonam

2004-01-01

A nested PCR assay to detect parasite DNA in slit aspirates from skin lesions of patients with post-kala-azar dermal lesihmaniasis (PKDL) is described. PCR results were positive in 27 of 29 (93%) samples by nested PCR assay, while only 20 of 29 (69%) were positive in a primary PCR assay. The nested PCR assay allowed reliable diagnosis of PKDL in a noninvasive manner.

Dermal, inhalation, and internal exposure to 1,6-HDI and its oligomers in car body repair shop workers and industrial spray painters

NARCIS (Netherlands)

Pronk, A.; Yu, F.; Vlaanderen, J.; Tielemans, E.; Preller, L.; Bobeldijk, I.; Deddens, J.A.; Latza, U.; Baur, X.; Heederik, D.

2006-01-01

Objectives: To study inhalation and dermal exposure to hexamethylene diisocyanate (HDI) and its oligomers as well as personal protection equipment (PPE) use during task performance in conjunction with urinary hexamethylene diamine (HDA) in car body repair shop workers and industrial spray painters.

Generation of human induced pluripotent stem cell lines from human dermal fibroblasts using a non-integration system

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Kyung-Ok Uhm

2017-05-01

Full Text Available We generated human induced pluripotent stem cells (hiPSCs from dermal fibroblasts using a Sendai virus (SeV-based gene delivery method. The generated hiPSC line, KSCBi002-A, has a normal karyotype (46,XY. The pluripotency and differentiation capacity were characterized by comparison with those of a human embryonic stem cell line. This cell line is registered and available from the National Stem Cell Bank, Korea National Institute of Health.

Dermal absorption behavior of fluorescent molecules in nanoparticles on human and porcine skin models.

Science.gov (United States)

Debotton, Nir; Badihi, Amit; Robinpour, Mano; Enk, Claes D; Benita, Simon

2017-05-30

The percutaneous passage of poorly skin absorbed molecules can be improved using nanocarriers, particularly biodegradable polymeric nanospheres (NSs) or nanocapsules (NCs). However, penetration of the encapsulated molecules may be affected by other factors than the nanocarrier properties. To gain insight information on the skin absorption of two fluorescent cargos, DiIC 18 (5) and coumarin-6 were incorporated in NSs or NCs and topically applied on various human and porcine skin samples. 3D imaging techniques suggest that NSs and NCs enhanced deep dermal penetration of both probes similarly, when applied on excised human skin irrespective of the nature of the cargo. However, when ex vivo pig skin was utilized, the cutaneous absorption of DiIC 18 (5) was more pronounced by means of PLGA NCs than NSs. In contrast, PLGA NSs noticeably improved the porcine skin penetration of coumarin-6, as compared to the NCs. Furthermore, the porcine skin results were reproducible when triplicated whereas from various human skin samples, as expected, the results were not sufficiently reproducible and large deviations were observed. The overall findings from this comprehensive comparison emphasize the potential of PLGA NCs or NSs to promote cutaneous bioavailability of encapsulated drugs, exhibiting different physicochemical properties but depending on the nature of the skin. Copyright © 2017 Elsevier B.V. All rights reserved.

Rhythmical Phenomena in Dermal Perfusion - Proved Assesment Strategies and new Discoveries

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Markus Huelsbusch

2005-01-01

Full Text Available The phenomena of rhythm fluctuation of arterial blood pressure were discovered already in the first continuous recordings in the 18th century. However the formation of such rhythms hasn’t been explained until now. This work presents two concepts which could aid in bringing new insights into the understanding of these rhythms. One development is a multisensor system capable to acquire multiple PPG channels, ECG and additionally breathing signals to correlate local and central driven oscillations. The second new development is Photoplethysmography Imaging which allows contactless measurements of cutaneous perfusion with spatial resolution. Together with the necessary mathematical analysis tools like the Wavelet Transform a sound basis for assessment and evaluation of rhythm fluctuations in human hemodynamics is provided. Using the presented framework new, previously unreported phenomena of distributed blood volume movements in dermal perfusion could be observed.