Papers by Paulo Gabbai-Armelin
Pharmaceutics
This study reports the fabrication of polymeric matrices through electrospinning using polymethyl... more This study reports the fabrication of polymeric matrices through electrospinning using polymethyl methacrylate (PMMA) and poly(lactic-co-glycolic acid) (PLGA), biocompatible polymers commonly used in medical systems. These polymers were combined with an antibacterial drug, sulfadiazine sodium salt (SDS) or its supramolecular system formed with hydroxypropyl-β-cyclodextrin (HPβ/CD) at 1:1 molar ratio, aiming to assemble a transdermal drug delivery system. The formation of fibers was confirmed by scanning electron microscopy (SEM), and the fibers’ surface properties were analyzed using contact angle and water vapor permeability techniques. Drug release tests and cell viability assays were performed to evaluate the potential toxicity of the material. SEM images demonstrated that the obtained fibers had nanoscale- and micrometer-scale diameters in PLGA and PMMA systems, respectively. The contact angle analyses indicated that, even in the presence of hydrophilic molecules (SDS and HPβCD)...
Journal of Biomaterials Applications
This study aimed to develop bone regenerative therapeutic strategies, based on the addition of bo... more This study aimed to develop bone regenerative therapeutic strategies, based on the addition of bone marrow stromal cells (BMSC) on bioglass/collagen (BG/COL) scaffolds. For this purpose, an in vivo study was conducted using tissue response of the BG/COL scaffolds combined with BMSC in a critical-size defects. Wistar rats were submitted to the surgical procedure to perform the cranial critical size bone defects and distributed in four groups (20 animals per group): Control Group (CG) (rats submitted to the cranial bone defect surgery without treatment), Bioglass Group (BG) (rats treated with BG), BG/COL Group (rats treated with BG/COL) and Bioglass/Collagen and BMSC Group (BG/COL/BMSC) (rats treated with BG/COL scaffolds enriched with BMSCs). Animals were euthanized 15 and 30 days after surgery. Scanning electron microscopy, histopathological and immunohistochemistry analysis were used. SEM analysis demonstrated that porous scaffolds were obtained, and Col fibers were successfully im...
Skin wounds represent a worldwide problem. Biopolymers have been attracting interest for healthca... more Skin wounds represent a worldwide problem. Biopolymers have been attracting interest for healthcare products toward wound dressing. Among these biopolymers, bacterial nanocellulose membranes (BNC), with its tridimensional and branched nano- and microfibrillar structure, are attractive. Despite that, BNC present no antimicrobial activity. Thus, the incorporation of the monoterpenes Carvacrol (Car) and Thymol (Thy) - which present antimicrobial and healing properties - toward the improvement of skin wound healing, consists of an appealing approach. This research aimed to produce and characterize nanocellulose membranes containing carvacrol and/or thymol, and investigate their release behavior, cytotoxicity and antimicrobial properties. BNC/Car, BNC/Thy and BNC/Car-Thy membranes were produced at doses of 0.1 and 1.0 mg/cm2. The natural components incorporation into the nanocellulose did not interfere neither on ultra-structure nor on its physic characteristics. Release experiments show...
Brazilian Archives of Biology and Technology, 2021
This study characterized the morphological aspects of marine collagenspongin (SPG) extract from m... more This study characterized the morphological aspects of marine collagenspongin (SPG) extract from marine sponges, as well as, evaluating its in vitro and in vivo biological performance. Aplysina fulva marine sponge was used for the SPG extraction. It was investigated the physicochemical and morphological properties of SPG by using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and compared to PMMA and bovine collagen. Additionally, the SPG cytotoxicity and its influence on cell proliferation, through in vitro tests. Moreover, the in vivo biological response was investigated using HIGHLIGHTS Marine collagensponginextract from specimens of the sponge Aplysina fulva. Spongin has physicochemical and morphological properties analogous to human collagen. Spongin is an alternative source of collagen for tissue engineering proposals.
European Journal of Clinical Investigation, 2021
Background: COVID-19 is an infectious disease caused by SARS-CoV-2 associated with haematological... more Background: COVID-19 is an infectious disease caused by SARS-CoV-2 associated with haematological manifestations (thrombolytic events). Aims: Considering the high prevalence of the thrombotic scenarios associated with COVID-19, the aim of this study was to perform a systematic review of the available literature, concerning the relation of COVID-19 and the thrombotic events, and identify prognostic factors for these events. Materials & Methods: PubMed, Web of Science and Scopus databases were searched. Independent reviewers conducted all flow diagram steps. For qualitative analysis, Oxford level of evidence and Newcastle-Ottawa scale were used in the eligible articles. For the prognostic factors, a meta-analysis was conducted to age, number of neutrophils and platelets, and levels of ferritin, C-reactive protein, lactate dehydrogenase and D-dimer. Publication bias was accessed by funnel plot and by trim-and-fill test. Trim-and-fill test was also applied to evaluate meta-analysis bias. Results: Twenty articles were included in the qualitative analysis, and 6 articles were included in the meta-analysis. Case-control studies showed bias related to exposure, and the main bias in cohort studies were related to selection and outcome. All articles received score 4 for the level of evidence. Hypertension and diabetes were the comorbidities more frequently associated with thrombolytic events. Significant results were found regarding D-dimer (P < .0001) and age (P = .0202) for thrombotic events in patients diagnosed with COVID-19. Conclusion: Patients older than 60 years, with hypertension, diabetes and D-Dimer values above 3.17 µg/mL, can be considered prognostic factors for developing thrombotic events due to COVID-19.
World Journal of Advanced Research and Reviews, 2021
One promising skin substitutes in the wound healing are the bacterial cellulose membranes (BCM). ... more One promising skin substitutes in the wound healing are the bacterial cellulose membranes (BCM). These biomaterials present nanostructures composed of microfibrils capable of forming three-dimensional pores that allow cell. In association with these biopolymers, several treatments are used, such as enrichment by growth factors and/or the application of photobiomodulation (PBM). Therefore, the aim of this study was to investigate the viability, proliferation and cytotoxicity of a BCM (culturing of Komagataeibacter xylinus), with or without FGF-2 in association with PBM therapy. In the characterization of BCM we saw that the membrane does not show great variations in pH and with the scanning electron microscopy it was possible to observe that the BCM has a denser and a porous side that allows the adhesion of fibroblasts, confirmed by histological staining and DAPI/Phalloidin. In vitro evaluation showed that the immunofluorescence (CaAM/EthD-1) for live and dead cells presented, in the...
GABBAI-ARMELIN, Paulo Roberto. Biocompatibilty of a scaffold obtained from a fibrous glassy mater... more GABBAI-ARMELIN, Paulo Roberto. Biocompatibilty of a scaffold obtained from a fibrous glassy material and its effect on bone repair. 2015. 119 p. Thesis (PhD in Biotechnology) – Postgraduate Course in Biotechnology, Federal University of São Carlos, São Paulo, 2015. Millions of bone fractures occur annually worldwide and the consequent bone repair process is complex, involving many biological events until it reaches the restoration of the tissue integrity. During that process some problems can occur due to delays in the bone healing, which does not allow the proper joining of the tissue. Thus, it is necessary to search for new technologies that work in restoring the integrity of the bone tissue and that promote the osteoconduction and the osteoinduction. In this sense, the use of bioactive materials in the bone repair process is a promising alternative. Following this, two studies (I and II) were developed in order to investigate a new fibrous glassy scaffold, and these studies were ...
Biofouling, 2020
This systematic review aimed to discuss the effects of arginine on caries-related microorganisms ... more This systematic review aimed to discuss the effects of arginine on caries-related microorganisms in different in vitro biofilm models. The eligibility criteria were in vitro studies that evaluated the effect of arginine at different concentrations on caries-related microorganisms using biofilm models. Eighteen studies published between 2012 and 2019 were included. Different bacterial species were studied. Seventeen studies (94.4%) achieved a low risk of bias and only one showed a medium risk of bias. The studies showed that arginine is a promising approach for the ecological management of dental caries. The focus of this review was to evaluate the effects of arginine on microorganisms involved in the mechanism of dental caries.
Brazilian Archives of Biology and Technology, 2020
Research on biomaterials of natural origin has gained prominence in the literature. Above all, ma... more Research on biomaterials of natural origin has gained prominence in the literature. Above all, marine sponges, due to their architecture and structural components, present a promising potential for the engineering of bone tissue. In vitro studies demonstrate that a biosilica of marine sponges has osteogenic potential. However, in vivo works are needed to elucidate the interaction of biosilica (BS) and bone tissue. The objective of the study was to evaluate the morphological and chemical characteristics of BS compared to Bioglass (BG) by scanning electron microscopy (SEM) and X-ray dispersive energy (EDX) spectroscopy. In addition, to evaluate the biological effects of BS, through an experimental model of tibial bone defect using histopathological, histomorphometric, immunohistochemical (IHC) and mechanical tests. SEM and EDX demonstrated the successful extraction of BS. Histopathological analysis demonstrated that Control Group (GC) had greater formation of newly formed bone tissue compared to BG and BS, yet BG bone neoformation was greater than BS. However, BS showed material degradation and granulation tissue formation, with HIGHLIGHTS BS was isolated from specimens of the marine sponge Tedania ignis collected in the north coast of São Paulo, Brazil. BS derived from marine sponges has been used as a promising raw material for bone grafts substitutes and tissue engineering proposes. The present work successfully obtained crystalline BS from marine sponges, able of properly interacting with bone tissue. The results are very inspiring toward further in vivo investigations. Cruz, M. A..; et al.
Scientific Reports, 2018
Osteoporosis represents a major health problem in terms of compromising bone strength and increas... more Osteoporosis represents a major health problem in terms of compromising bone strength and increasing the risk of bone fractures. It can be medically treated with bisphosphonates, which act systemically upon oral or venous administration. Further, bone regenerative treatments in osteoporotic conditions present a challenge. Here, we focused on the development of a synthetic bone substitute material with local diminishing effects on osteoporosis. Composites were created using calcium phosphate cement (CPC; 60 wt%) and polylactic-co-glycolic acid (PLGA; 40 wt%), which were loaded with alendronate (ALN). In vitro results showed that ALN-loaded CPC/PLGA composites presented clinically suitable properties, including setting times, appropriate compressive strength, and controlled release of ALN, the latter being dependent on composite degradation. Using a rat femoral condyle bone defect model in osteoporotic animals, ALN-loaded CPC/PLGA composites demonstrated stimulatory effects on bone fo...
LASER THERAPY, 2019
Background: Photobiomodulation presents stimulatory effects on tissue metabolism, constituting a ... more Background: Photobiomodulation presents stimulatory effects on tissue metabolism, constituting a promising strategy to produce bone tissue healing. Objective: the aim of the present study was to investigate the in vivo performance of PBM using an experimental model of cranial bone defect in rats. Material and Methods: rats were distributed in 2 different groups (control group and PBM group). After the surgical procedure to induce cranial bone defects, PBM treatment initiated using a 808 nm laser (100 mW, 30 J/cm 2 , 3 times/week). After 2 and 6 weeks, animals were euthanized and the samples were retrieved for the histopathological, histomorphometric, picrosirius red staining and immunohistochemistry analysis. Results: Histology analysis demonstrated that for PBM most of the bone defect was filled with newly formed bone (with a more mature aspect when compared to CG). Histomorphomeric analysis also demonstrated a higher amount of newly formed bone deposition in the irradiated animals, 2 weeks post-surgery. Furthermore, there was a more intense deposition of collagen for PBM, with ticker fibers. Results from Runx-2 immunohistochemistry demonstrated that a higher immunostaining for CG 2 week's post-surgery and no other difference was observed for Rank-L immunostaining. Conclusion: This current study concluded that the use of PBM was effective in stimulating newly formed bone and collagen fiber deposition in the sub-critical bone defect, being a promising strategy for bone tissue engineering.
Journal of Materials Science: Materials in Medicine, 2019
Bioactive glasses (BG) are known for their ability to bond to bone tissue. However, in critical s... more Bioactive glasses (BG) are known for their ability to bond to bone tissue. However, in critical situations, even the osteogenic properties of BG may be not enough to induce bone consolidation. Thus, the enrichment of BG with polymers such as Poly (D, L-lactic-co-glycolic) acid (PLGA) and associated to photobiomodulation (PBM) may be a promising strategy to promote bone tissue healing. The aim of the present study was to investigate the in vivo performance of PLGA supplemented BG, associated to PBM therapy, using an experimental model of cranial bone defect in rats. Rats were distributed in 4 different groups (Bioglass, Bioglass/PBM, Bioglas/PLGA and BG/PLGA/PBM). After the surgical procedure to induce cranial bone defects, the pre-set samples were implanted and PBM treatment (low-level laser therapy) started (808 nm, 100 mW, 30 J/ cm 2). After 2 and 6 weeks, animals were euthanized, and the samples were retrieved for the histopathological, histomorphometric, picrosirius red staining and immunohistochemistry analysis. At 2 weeks post-surgery, it was observed granulation tissue and areas of newly formed bone in all experimental groups. At 6 weeks post-surgery, BG/PLGA (with or without PBM) more mature tissue around the biomaterial particles. Furthermore, there was a higher deposition of collagen for BG/PLGA in comparison with BG/PLGA/PBM, at second time-point. Histomorphometric analysis demonstrated higher values of BM.V/TV for BG compared to BG/PLGA (2 weeks post-surgery) and N.Ob/T.Ar for BG/PLGA compared to BG and BG/PBM (6 weeks post-surgery). This current study concluded that the use of BG/PLGA composites, associated or not to PBM, is a promising strategy for bone tissue engineering.
Journal of Materials Science: Materials in Medicine, 2019
The combination of different biomaterials can be a promising intervention for the composites manu... more The combination of different biomaterials can be a promising intervention for the composites manufacture, mainly by adding functional and structural characteristics of each material and guarantee the advantages of the use of these composites. In this context, the aim of this study was to develop and evaluated the influence of the incorporation of marine spongin (SPG) into Biosilicate® (BS) in different proportions be used during bone repair. For this purpose, it was to develop and investigate different BS/SPG formulations for physico-chemical and morphological characteristics by pH, loss mass, Fourier transform infrared spectrometer (FTIR) and scanning electron microscope (SEM) analysis. Additionally, the influence of these composites on cell viability, proliferation, and alkaline phosphatase (ALP) activity were investigated. The results revealed that the pH values of all BS groups (with or without SPG) increased over time. A significant mass loss was observed in all composites, mainly with higher SPG percentages. Additionaly, SEM micrographies demonstrated fibers of SPG into BS and material degradation over time. Moreover, FTIR spectral analysis revealed characteristic peaks of PMMA, BS, and SPG in BS/SPG composites. BS/SPG groups demonstrated a positive effect for fibroblast proliferation after 3 and 7 days of culture. Additionally, BS and BS/SPG formulations (at 10% and 20% of SPG) presented similar values of osteoblasts viability and proliferation after 7 days of culture. Furthermore, ALP activity demonstrated no significant difference between BS and BS/ SPG scaffolds, at any composition. Based on the present in vitro results, it can be concluded that the incorporation of SPG into BS was possible and produced an improvement in the physical-chemical characteristics and in the biological performance of the graft especially the formulation with 80/20 and 90/10. Future research should focus on in vivo evaluations of this novel composite.
Journal of Biomaterials Applications, 2019
Bone disorders and fractures affect millions of people worldwide. In critical situations, proper ... more Bone disorders and fractures affect millions of people worldwide. In critical situations, proper healing may not happen which may lead to non-union fractures. Consequently, the development of new clinical approaches is necessary. In this context, the present work developed bioglass/collagen/magnesium composites in order to mimic natural bone, toward the enhancement of material mechanical properties, but keeping bioactivity and performance of bioglass and collagen. So, the aim of this investigation was to explore the biological outcomes of bioglass/collagen/magnesium composites over bone repair, using tibial defect in Wistar rats. For this purpose, histopathological, morphometrical and immunohistochemical analyses, as well as mechanical test, were performed after 15 and 45 days of the composites implantation in rats. Histopathological assessment indicated that the biocompatible composites degraded over time, leading to a progressive new bone formation from the border to the core of the defect. Immunohistochemistry showed that all groups presented runx-2 and Rank-L immunostaining, with improved runx-2 labeling for bioglass/magnesium compared to plain bioglass 45 days post-implantation. Mechanical tests of the tibiae indicated good mechanical properties of these Mgbased materials, but no statistical differences among groups were found. Additional studies should be done to confirm the outcomes of bioglass/collagen/magnesium on bone restoration, using different animal models and new balanced amounts of Mg (3 wt%< Mg < 5 wt%), as well as compromised, long-term and critical bone defect conditions.
Marine Biotechnology, 2018
Biomaterial-based bone grafts have an important role in the field of bone tissue engineering. One... more Biomaterial-based bone grafts have an important role in the field of bone tissue engineering. One of the most promising classes of biomaterials is collagen, including the ones from marine biodiversity (in general, called spongin (SPG)). Also, hydroxyapatite (HA) has an important role in stimulating bone metabolism. Therefore, this work investigated the association of HA and SPG composites in order to evaluate their physico-chemical and morphological characteristics and their in vitro biological performance. For this, pre-set composite disks were evaluated by means of mass loss after incubation, pH, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Bin vitro^cell viability. pH measurements showed no statistical difference between groups. Moreover, a higher mass loss was observed for HA/SPG70/30 compared to the other groups for all experimental periods. Moreover, SEM representative micrographs showed the degradation of the samples with and without immersion. FTIR analysis demonstrated the absorption peaks for poly(methyl methacrylate) (PMMA), HA, and SPG. A higher L292 cell viability for control and PMMA was observed compared to HA and HA/SPG 90/10. Also, HA/SPG 70/30 showed higher cell viability compared to HA and HA/SPG 90/10 on days 3 and 7 days of culture. Furthermore, HA showed a significant lower MC3T3 cell viability compared to control and HA/SPG 70/30 on day 3 and no significant difference was observed between the composites in the last experimental period. Based on our investigations, it can be concluded that the mentioned composites were successfully obtained, presenting improved biological properties, especially the one mimicking the composition of bone (with 70% of HA and 30% of SPG). Consequently, these data highlight the potential of the introduction of SPG into HA to improve the performance of the graft for bone regeneration applications. Further long-term studies should be carried out to provide additional information concerning the late stages of material degradation and bone healing in the presence of HA/SPG.
Journal of biomedical materials research. Part B, Applied biomaterials, Jan 23, 2018
This study evaluated physical-chemical characteristics of a vacuumed collagen-impregnated bioglas... more This study evaluated physical-chemical characteristics of a vacuumed collagen-impregnated bioglass (BG) scaffolds and bone marrow stromal cells (BMSCs) behavior on those composites. scanning electron microscope and energy dispersive x-ray spectroscope demonstrated collagen (Col) was successfully introduced into BG. Vacuum impregnation system has showed efficiency for Col impregnation in BG scaffolds (approximately 20 wt %). Furthermore, mass weight decreasing and more stabilized pH were observed over time for BG/Col upon incubation in phosphate buffered saline compared to plain BG under same conditions. Calcium evaluation (Ca assay) demonstrated higher calcium uptake for BG/Col samples compared to BG. In addition, BG samples presented hydroxyapatite crystals formation on its surface after 14 days in simulated body fluid solution, and signs of initial degradation were observed for BG and BG/Col after 21 days. Fourier transform infrared spectroscopy spectra for both groups indicated p...
Bio-medical materials and engineering, 2018
Burn injuries represent a high risk of morbidity and mortality. The wound healing process is comp... more Burn injuries represent a high risk of morbidity and mortality. The wound healing process is complex and requires the participation of different types of cells. Therefore, new biomaterials, which innovate the wound healing process, are being investigated. The aim of this study was to investigate the use of bacterial cellulose both in its pure state and enriched with lidocaine in full-thickness burns in rats. Thirty rats (Wistar) (260 ± 20 gramas) divided into control group (CG), bacterial cellulose membrane group (MG) and bacterial cellulose membrane enriched with lidocaine group (MLG) were used. The burns were induced using a 150°C heated soldering iron, held on the animal neck for 10 seconds. The biomaterial was applied immediately after injury and skin samples were collected on the tenth day of the treatment. The level of significance of p⩽0.05 was used for the conclusion of the statistical analysis. The groups treated with the biomaterials, a histological pattern compatible with...
Journal of Biomaterials Applications, 2017
Calcium phosphates and bioactive glass ceramics have been considered promising biomaterials for u... more Calcium phosphates and bioactive glass ceramics have been considered promising biomaterials for use in surgeries. However, their moldability should be further enhanced. We here thereby report the handling, physicochemical features, and morphological characteristics of formulations consisting of carboxymethylcellulose-glycerol and hydroxyapatite-tricalcium phosphate or Biosilicate Õ particles. We hypothesized that combining either material with carboxymethylcellulose-glycerol would improve handling properties, retaining their bioactivity. In addition to scanning electron microscopy, cohesion, mineralization, pH, and viscoelastic properties of the novel formulations, cell culture experiments were performed to evaluate the cytotoxicity and cell proliferation. Putty-like formulations were obtained with improved cohesion and moldability. Remarkably, mineralization in simulated body fluid of hydroxyapatite-tricalcium phosphate/ carboxymethylcellulose-glycerol formulations was enhanced compared to pure hydroxyapatite-tricalcium phosphate. Cell experiments showed that all formulations were noncytotoxic and that HA-TCP60 and BGC50 extracts led to an increased cell proliferation. We conclude that combining carboxymethylcellulose-glycerol with either hydroxyapatitetricalcium phosphate or Biosilicate Õ allows for the generation of moldable putties, improves handling properties, and retains the ceramic bioactivity.
Applied Surface Science, 2017
Highlights Bioactive Glasses (BG) is a group of synthetic silica-based materials that can be us... more Highlights Bioactive Glasses (BG) is a group of synthetic silica-based materials that can be used in bone repair. Collagen type I is critical for mechanical and biological roles. Powder and fibrous materials are capable of stimulating cell proliferation.
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Papers by Paulo Gabbai-Armelin