Porto Alegre, Brazil
Porto Alegre, Brazil

Time filter

Source Type

Sperling L.E.,Federal University of Rio Grande do Sul | Reis K.P.,Federal University of Rio Grande do Sul | Pozzobon L.G.,Federal University of Rio Grande do Sul | Girardi C.S.,Federal University of Rio Grande do Sul | And 2 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2017

Engineering neural tissue by combining biodegradable materials, cells and growth factors is a promising strategy for the treatment of central and peripheral nervous system injuries. In this study, neural differentiation of mouse embryonic stem cells (mESCs) was investigated in combination with three dimensional (3D) electrospun nanofibers as a substitute for the extracellular matrix (ECM). Nano/microfibrous poly(lactic-co-glycolic acid) (PLGA) 3D scaffolds were fabricated through electrospinning and characterized. The scaffolds consisted of either a randomly oriented or an aligned structure of PLGA fibers. The mESCs were induced to differentiate into neuronal lineage and the effect of the polymer and fiber orientation on cell survival, morphology and differentiation efficiency was studied. The neural progenitors derived from the mESCs could survive and migrate onto the fibrous scaffolds. Aligned fibers provided more contact guidance with the neurites preferentially extending along the long axis of fiber. The mESCs differentiated into neural lineages expressing neural markers as seen by the immunocytochemistry. The nestin and beta3-tubulin expression was enhanced on the PLGA aligned fibers in comparison with the other groups, as seen by the quantitative analysis. Taken together, a combination of electrospun fiber scaffolds and mESC derived neural progenitor cells could provide valuable information about the effects of topology on neural differentiation and axonal regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1333–1345, 2017. © 2017 Wiley Periodicals, Inc.


De Morais M.G.,Grande Rio University | Martins V.G.,Grande Rio University | Steffens D.,Federal University of Rio Grande do Sul | Pranke P.,Federal University of Rio Grande do Sul | And 2 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2014

Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices derived from engineering, physics, chemistry, and biology. Nanotechnology has opened up by rapid advances in science and technology, creating new opportunities for advances in the fields of medicine, electronics, foods, and the environment. Nanoscale structures and materials (nanoparticles, nanowires, nanofibers, nanotubes) have been explored in many biological applications (biosensing, biological separation, molecular imaging, anticancer therapy) because their novel properties and functions differ drastically from their bulk counterparts. Their high volume/surface ratio, improved solubility, and multifunctionality open many new possibilities. The objective of this review is to describe the potential benefits and impacts of the nanobiotechnology in different areas. Copyright © 2014 American Scientific Publishers All rights reserved.


Steffens D.,Federal University of Rio Grande do Sul | Leonardi D.,Federal University of Rio Grande do Sul | Da Luz Soster P.R.,Federal University of Rio Grande do Sul | Lersch M.,Federal University of Rio Grande do Sul | And 7 more authors.
Burns | Year: 2014

The combination of mesenchymal stem cells (MSCs) and nanotechnology to promote tissue engineering presents a strategy for the creation of new substitutes for tissues. Aiming at the utilization of the scaffolds of poly-D,L-lactic acid (PDLLA) associated or not with Spirulina biomass (PDLLA/Sp) in skin wounds, MSCs were seeded onto nanofibers produced by electrospinning. These matrices were evaluated for morphology and fiber diameter by scanning electron microscopy and their interaction with the MSCs by confocal microscopy analysis. The biomaterials were implanted in mice with burn imitating skin defects for up to 7 days and five groups were studied for healing characteristics. The scaffolds demonstrated fibrous and porous structures and, when implanted in the animals, they tolerated mechanical stress for up to two weeks. Seven days after the induction of lesions, a similar presence of ulceration, inflammation and fibrosis among all the treatments was observed. No group showed signs of re-epithelization, keratinization or presence of hair follicles on the lesion site. In conclusion, although there was no microscopical difference among all the groups, it is possible that more prolonged analysis would show different results. Moreover, the macroscopic analysis of the groups with the scaffolds showed better cicatrization in comparison with the control group. © 2014 Elsevier Ltd and ISBI. All rights reserved.


Steffens D.,Federal University of Rio Grande do Sul | Lersch M.,Federal University of Rio Grande do Sul | Rosa A.,Federal University of Rio Grande do Sul | Scher C.,Federal University of Rio Grande do Sul | And 5 more authors.
Journal of Biomedical Nanotechnology | Year: 2013

The association of stem cells (SCs) with biomaterials promises to be the protagonist for future regenerative medicine in the treatment of tissue and organ lesions. Stem cells were cultivated in scaffolds constructed by the electrospinning technique, using poly-D,L-lactic acid (PDLLA) associated or not with Spirulina biomass (PDLLA/Sp), which has bioactive components of interest for tissue engineering (TE). Physicochemical analyses were performed, such as morphology, fiber diameter, degradability, residual solvent, roughness, contact angle with water, among others. SCs adhesion, proliferation and scaffold cytotoxicity were also evaluated. Nanofibers without beads and with characteristics similar to the natural extracellular matrix (ECM) in terms of mechanical and topographical properties were obtained. In biological tests it was found that SCs adhered more and had greater viability in the PDLLA/Sp molds, when compared with the PDLLA scaffolds. The scaffolds were shown to be atoxic for the SCs. It can be concluded that the scaffolds developed in this work have the characteristics to be a new biomaterial suitable for use in TE. Copyright © 2013 American Scientific Publishers All rights reserved.


SEOUL, Korea, Nov 28, 2016 /PRNewswire/ -- Nature Cell Co., Ltd. (Nature Cell) (CEO, Dr. Jeongchan Ra), a leading biotechnology company, announces AstroStem's approval for Phase I and Phase II clinical trials for treatment of Alzheimer's disease by the U.S. Food and Drug Administration (FDA) on November 23. AstroStem is a therapeutic agent for adult stem cells that collects about 10g of fat from the patient's own abdominal subcutaneous tissue and separates only pure stem cells into a finished product, which is repeatedly administered intravenously to the patient. Production of the approved clinical trial materials will be done by the RBio Biostar Stem Cell Research Institute (Biostar), which has been developing technology for dementia reduction for more than 10 years. Dr. Jeongchan Ra of Biostar has collaborated with professor Yoohun Suh, a global brain research leader, to isolate the stem cell, which was cultivated with patented technology as an animal model for Alzheimer's disease. The results were published in PLoS One, a respected scientific journal, and recognized worldwide. The approval of the US FDA is significant milestone and is the first time in the world that a commercial clinical trial in which autologous adipose-derived stem cells are cultured and repeatedly administered intravenously has been approved. Biostar's technology for repeated intravenous administration of stem cells has already been applied more than 3,000 times in the past year to patients with autoimmune diseases who have been approved by Japan's Ministry of Health and Welfare. The clinical approval of Nature Cell's Alzheimer's disease treatment reconfirmed that the stem cells were cultured in Korea and received intravenous administration to U.S. patients during JontStem's Phase II clinical trial in the U.S. It is a great result that affirms the technological developments of the RBio Biostar Stem Cell Research Institute: Dr. Jeongchan Ra, who is in charge of the Alzheimer's disease Conversion Project, said, "The JointStem treatment of degenerative arthritis, AstroStem, a treatment for Alzheimer's disease, passing the U.S. FDA's examination and gaining approval to conduct clinical trials is a great opportunity. Adult stem cells are definitely Korea's future growth engine, so I ask for encouragement and support from the government and people." Dr. Jeongchan Ra talks more about the hope of overcoming dementia in his book "Dementia, It Has A Hope Now". To view the original version on PR Newswire, visit:http://www.prnewswire.com/news-releases/nature-cell-co-ltd-receives-us-fda-approval-for-phase-i-and-ii-alzheimers-clinical-trial-300368572.html


Braghirolli D.I.,Federal University of Rio Grande do Sul | Steffens D.,Federal University of Rio Grande do Sul | Quintiliano K.,Federal University of Rio Grande do Sul | Acasigua G.A.X.,Federal University of Rio Grande do Sul | And 5 more authors.
Journal of Biomedical Materials Research - Part B Applied Biomaterials | Year: 2014

The sterilization of scaffolds is an essential step for tissue engineering in vitro and, mainly, clinical biomaterial use. However, this process can cause changes in the structure and surface of the scaffolds. Therefore, the objective of this study was to investigate the effect of sterilization by ethanol, ultraviolet radiation (UVR) or antimicrobial solution (AMS) on poly(lactide-co-glycolide) (PLGA) scaffolds produced by the electrospinning technique. The properties of nanofibers and the cellular adhesion of mesenchymal stem cells to the scaffolds were analyzed after the treatments. All methods generated sterile scaffolds but showed some kind of damage to the scaffolds. Ethanol and AMS caused changes in the morphology and scaffold dimensions, which were not observed when using the UVR method. However, UVR caused a greater reduction in polymeric molecular weight, which increased proportionally with exposure time of treatment. Nanofibers sterilized with AMS for 1 h and 2 h showed greater cellular adhesion than the other methods, demonstrating their potential as a method for sterilizing PLGA nanofibers. © 2013 Wiley Periodicals, Inc.


Zanatta G.,Federal University of Rio Grande do Sul | Rudisile M.,University of Marburg | Camassola M.,Lutheran University of Brazil | Wendorff J.,University of Marburg | And 6 more authors.
Journal of Biomedical Nanotechnology | Year: 2012

Tissue engineering is a potential approach to regenerate damaged tissue by the combination and synergism among the scaffolding material, cell source and signaling factors. In the present study, mesenchymal stem cells (MSCs) were isolated from C57BL/6 mice, cultured on poly(D, L-lactide-co- glycolide) (PLGA) scaffold produced by electrospinning technique and differentiated into chondrogenic lineage. After seeding, MSCs were responsive and became flattened with fibroblast-like morphology demonstrated by the presence of actin stress fibers. Integrin-β1 receptor blockage reduced significantly cell adhesion with loss of actin stress fibers, demonstrating the ability of PLGA nanofiber to trigger integrin receptor-mediated cell adhesion. Present data contribute to the understanding of MSCs' behavior on these biodegradable and biocompatible scaffolds that can be used as carriers in treatments involving cell transplantation. Copyright © 2012 American Scientific Publishers All rights reserved.


Braghirolli D.I.,Federal University of Rio Grande do Sul | Steffens D.,Federal University of Rio Grande do Sul | Pranke P.,Federal University of Rio Grande do Sul | Pranke P.,Stem Cell Research Institute
Drug Discovery Today | Year: 2014

Electrospun fibers are promising tissue engineering scaffolds that offer the cells an environment that mimics the native extracellular matrix. Fibers with different characteristics can be produced by the electrospinning technique according to the needs of the tissue to be repaired. In this review, the process of electrospinning was examined, providing a description of the common techniques used for the physicochemical and biological characterization of electrospun fibers. The review also discusses the potential applications of electrospun scaffolds for tissue engineering, based on scientific literature. © 2014 Elsevier Ltd.


Acasigua G.A.X.,Federal University of Rio Grande do Sul | Bernardi L.,Federal University of Rio Grande do Sul | Braghirolli D.I.,Federal University of Rio Grande do Sul | Filho M.S.,Federal University of Rio Grande do Sul | And 3 more authors.
Current Stem Cell Research and Therapy | Year: 2014

Currently, there are a number of alternatives for bone grafting, though when used correctly they present physical, chemical or biological limitations, which justifies the pursuit for new alternatives for bone regeneration. This study gives a report on the potential for bone regeneration in the use of biodegradable nanofibers from poly (lactic-co-glycolic acid) (PLGA) in association with human mesenchymal stem cells from dental pulp of deciduous teeth (SCDT). Five samples of SCDT were seeded with scaffolds (test) or without scaffolds (control) for cell adhesion and viability assay. To evaluate the ability of the association in promoting bone formation, critical defects were made in the calvarium of rats (n=20), which were then divided into the following groups: I - sham group; II - implant of scaffolds; III - scaffolds/SCDT; and IV - scaffolds/SCDT. They were kept for 13 days in osteogenic media. After 60 days, the histomorphometric analysis was performed. It was observed that the adherence and viability of SCDT in the control and test group were similar throughout the experiment (p>0.05). The association of scaffolds/SCDT maintained in osteogenic media, showed greater bone formation than the other groups (p<0.05). The study demonstrated that the association of SCDT seeded in biodegradable PLGA scaffolds has the ability to promote bone regeneration in rats, which is a promising alternative for application in regenerative medicine. © 2014 Bentham Science Publishers.


Pranke P.,Federal University of Rio Grande do Sul | Pranke P.,Stem Cell Research Institute | Chagastelles P.,Federal University of Rio Grande do Sul | Sperling L.E.,Federal University of Rio Grande do Sul
Stem Cells and Development | Year: 2014

This article provides a brief overview of research with human pluripotent stem cells in Brazil, the federal funding supporting this research, and the legislation that allows the isolation of human embryonic stem cells. © 2014 Mary Ann Liebert, Inc.

Loading Stem Cell Research Institute collaborators
Loading Stem Cell Research Institute collaborators