699 research outputs found
Skin Tissue Models
Skin Tissue Models provides a translational link for biomedical researchers on the interdisciplinary approaches to skin regeneration. As the skin is the largest organ in the body, engineered substitutes have critical medical application to patients with disease and injury - from burn wounds and surgical scars, to vitiligo, psoriasis and even plastic surgery. This volume offers readers preliminary description of the normal structure and function of mammalian skin, exposure to clinical problems and disease, coverage of potential therapeutic molecules and testing, skin substitutes, models as study platforms of skin biology and emerging technologies. The editors have created a table of contents which frames the relevance of skin tissue models for researchers as platforms to study skin biology and therapeutic approaches for different skin diseases, for clinicians as tissue substitutes, and for cosmetic and pharmaceutical industries as alternative test substrates that can replace animal models. Offers descriptions of the normal structure/function of mammalian skin, exposure to clinical problems, and more Presents coverage of skin diseases (cancer, genodermatoses, vitiligo and psoriasis) that extends to clinical requirements and skin diseases in vitro models Addresses legal requirements and ethical concerns in drugs and cosmetics in vitro testing Edited and authored by internationally renowned group of researchers, presenting the broadest coverage possible. © 2018 Elsevier Inc. All rights reserved.(undefined)info:eu-repo/semantics/publishedVersio
Semipermeable capsules wrapping a multifunctional and self-regulated co-culture microenvironment for osteogenic differentiation
A new concept of semipermeable reservoirs containing co-cultures of cells and supporting microparticles is presented, inspired by the multi-phenotypic cellular environment of bone. Based on the deconstruction of the â stem cell nicheâ , the developed capsules are designed to drive a self-regulated osteogenesis. PLLA microparticles functionalized with collagen I, and a co-culture of adipose stem (ASCs) and endothelial (ECs) cells are immobilized in spherical liquified capsules. The capsules are coated with multilayers of poly(L-lysine), alginate, and chitosan nano-assembled through layer-by-layer. Capsules encapsulating ASCs alone or in a co-culture with ECs are cultured in endothelial medium with or without osteogenic differentiation factors. Results show that osteogenesis is enhanced by the co-encapsulation, which occurs even in the absence of differentiation factors. These findings are supported by an increased ALP activity and matrix mineralization, osteopontin detection, and the up regulation of BMP-2, RUNX2 and BSP. The liquified co-capsules also act as a VEGF and BMP-2 cytokines release system. The proposed liquified capsules might be a valuable injectable self-regulated system for bone regeneration employing highly translational cell sources.The authors acknowledge the financial support by the Portuguese Foundation for Science and Technology (FCT)
through the Ph.D. (SFRH/BD/69529/2010-Clara R. Correia) and the Post-doc grants (SFRH/BPD/96611/2013-
Mariana T. Cerqueira), and the funding of RL3-TECT-NORTE-01-0124-FEDER-000020 for Rogério P. Pirraco.
This work was also supported by European Research Council grant agreement ERC-2014-ADG-669858 for
project ATLAS
Stem cell-containing hyaluronic acid-based spongy hydrogels for integrated diabetic wound healing
The detailed pathophysiology of diabetic foot ulcers is yet to be established and improved treatments are still
required. We propose a strategy that directs inflammation, neovascularization, and neoinnervation of diabetic
wounds. Aiming to potentiate a relevant secretome for nerve regeneration, stem cells were precultured in
hyaluronic acid-based spongy hydrogels under neurogenic/standard media before transplantation into diabetic
mice full-thickness wounds. Acellular spongy hydrogels and empty wounds were used as controls. Reepithelialization
was attained 4 weeks after transplantation independently of the test groups, whereas a
thicker and more differentiated epidermis was observed for the cellular spongy hydrogels. A switch from the
inflammatory to the proliferative phase of wound healing was revealed for all the experimental groups 2 weeks
after injury, but a significantly higher M2(CD163
þ
)/M1(CD86
þ
) subtype ratio was observed in the neurogenic
preconditioned group that also failed to promote neoinnervation. A higher number of intraepidermal nerve
fibers were observed for the unconditioned group probably due to a more controlled transition from the inflammatory
to the proliferative phase. Overall, stem cell-containing spongy hydrogels represent a promising
approach to enhance diabetic wound healing by positively impacting re-epithelialization and by modulating
the inflammatory response to promote a successful neoinnervation.The authors would like to acknowledge Gene2Skin Project (H2020-TWINN2015-692221)
and Fundac¸a˜o para a Cieˆncia e Tecnologia for SFRH/BD/
78025/2011 (LPdS), SFRH/BPD/96611/2013 (MTC), SFRH/BPD/101886/2014
(RPP), SFRH/BPD/101952/2014 (TCS) grants. Moreover, the authors would
also like to acknowledge Teresa Oliveira for histology support, Andreia Carvalho
for hASCs supply, Luca Gasperini for cell profiler analysis, and Manuela
E. L. Lago and Carla M. Abreu for intraepidermal nerve fiber quantification.info:eu-repo/semantics/publishedVersio
Extracellular matrix in skin diseases: the road to new therapies
"Article in Press"Background: The extracellular matrix (ECM) is a vital structure with a dynamic and complex organization
that plays an essential role in tissue homeostasis. In the skin, the ECM is arranged into two types of com-
partments: interstitial dermal matrix and basement membrane (BM). All evidence in the literature sup-
ports the notion that direct dysregulation of the composition, abundance or structure of one of these
types of ECM, or indirect modifications in proteins that interact with them is linked to a wide range of
human skin pathologies, including hereditary, autoimmune, and neoplastic diseases. Even though the
ECMâ s key role in these pathologies has been widely documented, its potential as a therapeutic target
has been overlooked.
Aim of review: This review discusses the molecular mechanisms involved in three groups of skin ECM-
related diseases - genetic, autoimmune, and neoplastic â and the recent therapeutic progress and oppor-
tunities targeting ECM.
Key scientific concepts of review: This article describes the implications of alterations in ECM components
and in BM-associated molecules that are determinant for guaranteeing its function in different skin dis-
orders. Also, ongoing clinical trials on ECM-targeted therapies are discussed together with future oppor-
tunities that may open new avenues for treating ECM-associated skin diseases.This work was supported by ERC Consolidator Grant – ECM_INK
(ERC-2016-COG-726061) (A. P. Marques and FCT with grant SFRH/
BD/137766/2018 (M. D. Malta) and contract from Norte-01-0145-
FEDER-02219015 (M. T. Cerqueira)
Modification of ZnO nanoparticles with silanes enables their application as anticancer agents
Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio
Interfollicular epidermal stem-like cells for the recreation of the hair follicle epithelial compartment
Background
Hair follicle (HF) development and growth are dependent on epithelial-mesenchymal interactions (EMIs). Dermal papilla (DP) cells are recognized as the key inductive mesenchymal player, but the ideal source of receptive keratinocytes for human HF regeneration is yet to be defined. We herein investigated whether human interfollicular epidermal keratinocytes with stem-like features (EpSlKCs), characterized by a α6bri/CD71dimexpression, can replace human hair follicular keratinocytes (HHFKCs) for the recreation of the HF epithelium and respective EMIs.
Methods
The α6bri/CD71dim cellular fraction was selected from the whole interfollicular keratinocyte population through fluorescence-activated cell sorting and directly compared with follicular keratinocytes in terms of their proliferative capacity and phenotype. The crosstalk with DP cells was studied in an indirect co-culture system, and EpSlKC hair forming capacity tested in a hair reconstitution assay when combined with DP cells.
Results
EpSlKCs exhibited a phenotypic profile similar to follicular keratinocytes and were capable of increasing DP cell proliferation and, for short co-culture times, the number of alkaline phosphatase-active cells, suggesting an improvement of their inductivity. Moreover, the recreation of immature HFs and sebaceous glands was observed after EpSlKC and DP cell co-grafting in nude mice.
Conclusions
Our results suggest that EpSlKCs are akin to follicular keratinocytes and can crosstalk with DP cells, contributing to HF morphogenesis in vivo, thus representing an attractive epithelial cell source for hair regeneration strategies.This study was supported by the FCT/MCTES (Fundação para a Ciência e a
Tecnologia/Ministério da Ciência, Tecnologia, e Ensino Superior) through the
PD/59/2013, PD/BD/113800/2015 (C.M. Abreu), CEECIND/00695/2017 (M.T.
Cerqueira), IF/00347/2015 (R. P. Pirraco), and IF/00945/2014 (A.P. Marques)
grants
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Pre-selection of fibroblasts subsets prompt prevascularization of tissue engineered skin analogues
The papillary and reticular dermis harbors phenotypically distinct fibroblasts, whose functions such as maintenance of skin's microvasculature are also distinct. Thus, we hypothesized that pre-selection of the subpopulations of fibroblasts would benefit the generation of skin tissue engineered (TE) constructs, promoting their prevascularization in vitro. We first isolated papillary and reticular fibroblasts using fluorescence-activated cell sorting and studied the effect of their secretome and extracellular matrix (ECM) on human dermal microvascular endothelial cell (hDMEC) organization. Subsequently, we developed a bilayered 3D polymeric structure with distinct layer-associated features to house the subpopulations of fibroblasts, to generate a skin analogue. Both papillary and reticular fibroblasts were able to stimulate capillary-like network formation in a Matrigel assay. However, the secretome of the two subpopulations was substantially different, being enriched in VEGF, IGF-1, and Angio-1 in the case of papillary fibroblasts and in HGF and FGF-2 for the reticular subset. In addition, the fibroblast subpopulations deposited varied levels of ECM proteins, more collagen I and laminin was produced by the reticular subset, but these differences did not impact hDMEC organization. Vessel-like structures with lumens were observed earlier in the 3D skin analogue prepared with the sorted fibroblasts, although ECM deposition was not affected by the cell's pre-selection. Moreover, a more differentiated epidermal layer was obtained in the skin analogue formed by the sorted fibroblasts, confirming that its whole structure was not affected. Overall, we provide evidence that pre-selection of papillary and reticular fibroblasts is relevant for promoting the in vitro prevascularization of skin TE constructs.The authors would like to acknowledge the financial support from the Consolidator Grant “ECM_INK” (ERC-2016- COG-726061), to the FSE/POCH (Fundo Social Europeu através do Programa Operacional do Capital Humano) under the scope of the PD/169/2013, NORTE-08-5369-FSE-000037 (H.R. M.)
Overlapping SETBP1 gain-of-function mutations in Schinzel-Giedion syndrome and hematologic malignancies
Schinzel-Giedion syndrome (SGS) is a rare developmental disorder characterized by multiple malformations, severe neurological alterations and increased risk of malignancy. SGS is caused by de novo germline mutations clustering to a 12bp hotspot in exon 4 of SETBP1. Mutations in this hotspot disrupt a degron, a signal for the regulation of protein degradation, and lead to the accumulation of SETBP1 protein. Overlapping SETBP1 hotspot mutations have been observed recurrently as somatic events in leukemia. We collected clinical information of 47 SGS patients (including 26 novel cases) with germline SETBP1 mutations and of four individuals with a milder phenotype caused by de novo germline mutations adjacent to the SETBP1 hotspot. Different mutations within and around the SETBP1 hotspot have varying effects on SETBP1 stability and protein levels in vitro and in in silico modeling. Substitutions in SETBP1 residue I871 result in a weak increase in protein levels and mutations affecting this residue are significantly more frequent in SGS than in leukemia. On the other hand, substitutions in residue D868 lead to the largest increase in protein levels. Individuals with germline mutations affecting D868 have enhanced cell proliferation in vitro and higher incidence of cancer compared to patients with other germline SETBP1 mutations. Our findings substantiate that, despite their overlap, somatic SETBP1 mutations driving malignancy are more disruptive to the degron than germline SETBP1 mutations causing SGS. Additionally, this suggests that the functional threshold for the development of cancer driven by the disruption of the SETBP1 degron is higher than for the alteration in prenatal development in SGS. Drawing on previous studies of somatic SETBP1 mutations in leukemia, our results reveal a genotype-phenotype correlation in germline SETBP1 mutations spanning a molecular, cellular and clinical phenotype
Electrospray Deposition of PEDOT:PSS on Carbon Yarn Electrodes for Solid-State Flexible Supercapacitors
Funding Information: This work was financed by national funds from FCT─Fundação para a Ciência e a Tecnologia, I.P., in the scope of the All-FIBRE project with the reference PTDC/CTM-CTM/1571/2020, and the projects LA/P/0037/2020, UIDP/50025/2020, and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling, and Nanofabrication─i3N. This work was also supported by ERC-CoG-2014, CapTherPV, 647596. The authors would like to thank Professor Daniela Gomes from CENIMAT for the SEM images. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society.The increasing demand for flexible electronic devices has risen due to the high interest in electronic textiles (e-textiles). Consequently, the urge to power e-textiles has sparked enormous interest in flexible energy storage devices. One-dimensional (1D) configuration supercapacitors are the most promising technology for textile applications, but often their production involves complex synthesis techniques and expensive materials. This work unveils the use of the novel electrospray deposition (ESD) technique for the deposition of poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS). This deposition methodology on conductive carbon yarns creates flexible electrodes with a high surface area. The deposition conditions of PEDOT:PSS were optimized, and their influence on the electrochemical performance of a 1D symmetric supercapacitor with a cellulose-based gel as an electrolyte and a separator was evaluated. The tests herein reported show that these capacitors exhibited a high specific capacitance of 72 mF g-1, an excellent cyclability of more than 85% capacitance retention after 1500 cycles, and an outstanding capability of bending.publishersversionpublishe
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