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1.
Carbohydr Polym ; 283: 119145, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35153024

RESUMO

Polysaccharide-based hydrogels are achieving remarkable performances in chronic wounds treatment. In this work, a carboxymethyl cellulose-based hydrogel film was developed to support skin repair. The hydrogel was loaded with berberine, a polyphenolic molecule endowing antioxidant and cytoprotective features. The film was physico-chemically characterized and in vitro tested on keratinocytes and fibroblasts subjected to oxidative stress. The biocomposite showed high thermal stability (onset decomposition temperature 245 °C) and significant fluid uptake performances, both in free conditions (up to 6510%) and under external pressure (up to 3400%). Moreover, it was able to control oxidative stress and inflammation markers involved in wound chronicity. Keratinocytes hyperproliferation, features that normally hamper injury restoration, was reduced of 25%. Our results showed that the combination of berberine and hydrogel provides a synergic improvement of the material properties. The biocomposite represents a promising candidate for dermatological applications against oxidative stress at the chronic wound site, promoting the healing process.


Assuntos
Berberina/farmacologia , Carboximetilcelulose Sódica/química , Hidrogéis/farmacologia , Cicatrização/efeitos dos fármacos , Antioxidantes/farmacologia , Bandagens , Berberina/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogéis/química , Queratinócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura
2.
J Exp Orthop ; 9(1): 13, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079910

RESUMO

PURPOSE: The aim of this study was to investigate the presence of synovial mast cells (MCs) in hip and knee tissue from osteoarthritis (OA) patients and to correlate them with clinical and radiological data. METHODS: Synovial tissue was obtained during arthroplasty from 60 patients, 30 with knee OA and 30 with hip OA. Control synovial tissue was obtained from 30 patients without OA, 15 undergoing above-knee amputation and 15 receiving a hip replacement for fracture. Before surgery, the radiographic findings were graded according to the Kellgren-Lawrence system and clinical data including pain (VAS) and functional information (KOOS and HOOS) was collected. The tissue was stained with hematoxylin-eosin and toluidine blue for histochemistry and incubated with CD117 and CD31 antibodies for immunohistochemistry. MC and vessel number and synovitis score were determined in all samples. RESULTS: Mean MC number, synovitis score and vessel number were significantly higher in the OA samples (p < 0.05) than in control tissue. MC number correlated with the synovitis score and disease severity in both patient groups. CONCLUSIONS: The prevalence of MCs in synovium from OA patients and their association with synovial inflammation and pain suggest a role for them in OA pathophysiology.

4.
Eur Rev Med Pharmacol Sci ; 24(16): 8566-8572, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32894561

RESUMO

OBJECTIVE: Muscle injury tends to heal with incomplete functional recovery. Among the growth factors released in the physio-pathological response of muscle lesion, the Insulin-like Growth-Factor-1 (IGF-1) results in an engine factor of the reparation program. The therapeutic use of growth factors has been exploited to improve healing. As IGF-1 is a primary mediator of the effects of growth hormone (GH), we exploited its systemic administration to muscle recovery in a rat model of muscle injury. MATERIALS AND METHODS: Monolateral lesion of the longissimus dorsi muscle of rats was performed. Animals were divided into 5 groups: four groups for histological studies and serum hormone dosage, whilst the fifth group represented the uninjured control. Rat GH was intraperitoneally administered after 24h from the surgical lesion at three different concentrations (0.1, 0.2, 0.4 mg/kg). At 3 days from surgery, immunohistochemical and histological analyses evaluated the expression of MyoD and Myogenin, and the presence of neovascularization and inflammation, respectively. After 2 months, we analyzed the presence of muscle regeneration and fibrosis. RESULTS: The treatment with GH resulted in a significant increase in neovascularization and Myogenin expression at 24h from injury in comparison with the control. This suggested speed up biological recovery times. After two-months, a dose-dependent increase of the connective component was observed. CONCLUSIONS: The potential effect of GH on muscle repair and regeneration, through the activation of satellite cells already demonstrated in vitro, was confirmed in this in vivo experimental approach. This study sheds light on the role of growth factors in damage repair mechanisms to find an appropriate biological treatment for muscle injury.


Assuntos
Modelos Animais de Doenças , Hormônio do Crescimento/farmacologia , Músculo Esquelético/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Hormônio do Crescimento/administração & dosagem , Hormônio do Crescimento/sangue , Injeções Intraperitoneais , Masculino , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Ratos , Ratos Wistar
5.
Eur Cell Mater ; 37: 175-185, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30805914

RESUMO

Stem cells are essential for tissue homeostasis and regeneration throughout the lifespan of multicellular organisms. The decline in stem cell function during advanced age is associated with a reduced regenerative potential of tissues that leads to an increased frequency of diseases. Age-related changes also occur in the dental pulp that represents a reliable model tissue, with high regenerative capability, for studying senescence mechanisms. However, little information is available concerning the effects of ageing on dental stem-cell function. In this mini-review, recent data on how the molecular and functional alterations that accumulate in stem cell populations during ageing result in modifications of dental pulp physiology are discussed. Changes that accumulate during ageing such as how reduction of pulp chamber volume, decreased vascular supply and modifications to the stem cell niches affect stem cell functions and, therefore, dental pulp regenerative potential in response to various stressful agents. Dental pulp cells from aged individuals are still metabolically active and secrete pro-inflammatory and matrix-degrading molecules. Furthermore, miRNAs and exosomes derived from dental pulp stem cells constitute an attractive source of nanovesicles for the treatment of age-related dental pathologies. Further investigation of the epigenetic alterations in dental pulp stem cells, accumulating during ageing, might reveal crucial information for potential stem cell-based therapeutic approaches in the elderly.


Assuntos
Envelhecimento/fisiologia , Polpa Dentária/citologia , Células-Tronco/citologia , Dente/fisiologia , Animais , Exossomos/metabolismo , Humanos , Inflamação/patologia
6.
Clin Exp Immunol ; 193(2): 234-240, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29676778

RESUMO

Psoriasis microenvironment, characterized by an imbalance between T helper type 1 (Th1)/Th17 and Th2 cytokines and also influences the mesenchymal stem cells (MSCs) phenotypical profile. MSCs from healthy donors (H-MSCs) can exert a strong paracrine effect by secreting active soluble factors, able to modulate the inflammation in the microenvironment. To evaluate the influence of H-MSCs on MSCs from psoriatic patients (PsO-MSCs), H-MSCs and PsO-MSCs were isolated and characterized. Indirect co-culture of H-MSCs with PsO-MSCs was performed; effects on proliferation and expression of cytokines linked to Th1/Th17 and Th2 pathways were assayed before and after co-culture. The results show that before co-culture, proliferation of PsO-MSCs was significantly higher than H-MSCs (P < 0·05) and the levels of secreted cytokines confirmed the imbalance of Th1/Th17 versus the Th2 axis. After co-culture of H-MSCs with PsO-MSCs, healthy MSCs seem to exert a 'positive' influence on PsO-MSCs, driving the inflammatory phenotypical profile of PsO-MSCs towards a physiological pattern. The proliferation rate decreased towards values nearer to those observed in H-MSCs and the secretion of the cytokines that mostly identified the inflammatory microenvironment that characterized psoriasis, such as interleukin (IL)-6, IL-12, IL-13, IL-17A, tumour necrosis factor (TNF)-α and granulocyte-macrophage colony-stimulating factor (G-CSF), is significantly lower in co-cultured PsO-MSCs than in individually cultured PSO-MSCs (P at least < 0·05). In conclusion, our preliminary results seem to provide an intriguing molecular explanation for the ever-increasing evidence of therapeutic efficacy of allogeneic MSCs infusion in psoriatic patients.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Psoríase/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia , Proliferação de Células , Células Cultivadas , Microambiente Celular , Técnicas de Cocultura , Citocinas/metabolismo , Voluntários Saudáveis , Humanos , Comunicação Parácrina , Fenótipo , Psoríase/terapia , Equilíbrio Th1-Th2 , Transplante Homólogo
7.
J Tissue Eng Regen Med ; 11(7): 1986-1997, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-26510714

RESUMO

The aim of this work was the fabrication and characterization of bioactive glass-poly(lactic-co-glycolic acid) (PLGA) composite scaffolds mimicking the topological features of cancellous bone. Porous multilayer PLGA-CEL2 composite scaffolds were innovatively produced by a pressure-activated microsyringe (PAM) method, a CAD/CAM processing technique originally developed at the University of Pisa. In order to select the optimal formulations to be extruded by PAM, CEL2-PLGA composite films (CEL2 is an experimental bioactive SiO2 -P2 O5 -CaO-MgO-Na2 O-K2 O glass developed at Politecnico di Torino) were produced and mechanically tested. The elastic modulus of the films increased from 30 to > 400 MPa, increasing the CEL2 amount (10-50 wt%) in the composite. The mixture containing 20 wt% CEL2 was used to fabricate 2D and 3D bone-like scaffolds composed by layers with different topologies (square, hexagonal and octagonal pores). It was observed that the increase of complexity of 2D topological structures led to an increment of the elastic modulus from 3 to 9 MPa in the composite porous monolayer. The elastic modulus of 3D multilayer scaffolds was intermediate (about 6.5 MPa) between the values of the monolayers with square and octagonal pores (corresponding to the lowest and highest complexity, respectively). MG63 osteoblast-like cells and periosteal-derived precursor cells (PDPCs) were used to assess the biocompatibility of the 3D bone-like scaffolds. A significant increase in cell proliferation between 48 h and 7 days of culture was observed for both cell phenotypes. Moreover, qRT-PCR analysis evidenced an induction of early genes of osteogenesis in PDPCs. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Regeneração Óssea , Vidro/química , Ácido Láctico/química , Teste de Materiais , Osteoblastos/metabolismo , Ácido Poliglicólico/química , Alicerces Teciduais/química , Linhagem Celular , Humanos , Osteoblastos/citologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pressão , Seringas
8.
Data Brief ; 7: 1335-40, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27158646

RESUMO

This data article is related to our recently published research paper "Exploiting a new glycerol-based copolymer as a route to wound healing: synthesis, characterization and biocompatibility assessment", De Giglio et al. (Colloids and Surfaces B: Biointerfaces 136 (2015) 600-611) [1]. The latter described a new copolymer derived from glycerol and tartaric acid (PGT). Herein, an investigation about the PGT-ciprofloxacin (CIP) interactions by means of Fourier Transform Infrared Spectroscopy (FT-IR) acquired in Attenuated Total Reflectance (ATR) mode and Differential Scanning Calorimetry (DSC) was reported. Moreover, CIP release experiments on CIP-PGT patches were performed by High Performance Liquid Chromatography (HPLC) at different pH values.

9.
J Biol Regul Homeost Agents ; 29(4 Suppl): 47-55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26652490

RESUMO

Skeletal muscle injuries are common causes of severe long-term pain and physical disability, accounting for up to 55% of all sports injuries. The phases of the healing processes after direct or indirect muscle injury are complex but clearly defined and include well-coordinated steps: degeneration, inflammation, regeneration, and fibrosis. Despite this frequent occurrence and the presence of a body of data on the pathophysiology of muscle injuries, none of the current treatment strategies have shown to be really effective in strictly controlled trials. Platelet-rich plasma (PRP) is a promising alternative approach based on the ability of autologous growth factors (GFs) to accelerate tissue healing, improve muscular regeneration, increase neovascularization and reduce fibrosis. The present study is focused on the use of different concentrations of PRP as a source of GFs. Unilateral muscle lesions were created on the longissimus dorsi muscle of Wistar rats. Twenty-four h after surgical trauma, the lesion was filled with an intramuscular injection of PRP at 2 different concentrations. A group of rats were left untreated (controls). Animals were sacrificed at 3, 15 and 60 days from surgery. Histological, immunohistochemical and histomorphometric analyses were performed to evaluate muscle regeneration, neovascularization, fibrosis and inflammation. The PRP-treated muscles showed better muscle regeneration, more neovascularization and a slight reduction of fibrosis compared with the control muscles in a dose dependent manner. However, further studies also assessing pain and functional recovery are scheduled.

10.
Colloids Surf B Biointerfaces ; 136: 600-11, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26461426

RESUMO

The use of biocompatible materials based on naturally derived monomers plays a key role in pharmaceutical and cosmetic industries. In this paper we describe the synthesis of a new low molecular weight copolymer, based on glycerol and l-tartaric acid, useful to develop biocompatible dermal patches with drug delivery properties. The copolymer's chemical composition was assessed by FT-IR (Fourier transform infrared spectroscopy), (1)H NMR ((1)H Nuclear Magnetic Resonance) and XPS (X-ray photoelectron spectroscopy), while its molecular weight distribution was estimated by SEC (size exclusion chromatography). Copolymer thermal properties were studied by TGA (thermogravimetric analysis). Biological evaluations by MTT assay and SEM (scanning electron microscopy) observations performed with murine fibroblasts and human keratinocytes (HaCaT) revealed a good compatibility of the proposed copolymer. Ciprofloxacin was selected as model drug and its release was evaluated by HPLC (high performance liquid chromatography), showing that the new copolymer supplied promising results as drug delivery system for wound healing applications. Furthermore, investigations on Skin-Mesenchymal stem cells (S-MSCs) behaviour and gene expression showed that the copolymer and its combination with ciprofloxacin did not affect their stemness. In this regard, the fabrication of dermal patches with new, low cost materials for local treatment of skin infections represents an attractive strategy in order to bypass the worrying side effects of systemic antibiotic therapy. Overall, the performed physico-chemical characterization, drug release test and biological evaluations showed that this new copolymer could be a promising tool for the in situ delivery of bioactive molecules during skin lesions treatment.


Assuntos
Materiais Biocompatíveis , Glicerol/química , Polímeros/química , Cicatrização , Animais , Linhagem Celular , Humanos , Camundongos , Microscopia Eletrônica de Varredura , Espectroscopia de Prótons por Ressonância Magnética
11.
Surg Radiol Anat ; 37(3): 281-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25047541

RESUMO

Achilles tendon analysis represents one of the most frequently requested ultrasonographic evaluations, due to the high incidence of tendinopathy. Various authors have described inflammatory features of the paratenon recruited 22 subjects complaining of pain in the mid-portion of the Achilles tendon and 22 healthy subjects. Both groups underwent ultrasonographic examination and Victorian Institute of Sport Assessment-Achilles questionnaire administration. It was found statistically significant inter-group differences of the paratenon (p = 0.0001) as well as tendon thickness (p < 0.0001). Our results show that Achilles symptoms could also be associated with an increase in the paratenon thickness. We suggest that clinicians should carefully analyze paratenon thickness when evaluating patients with Achillodynia using ultrasound. It may be that the paratenon, when thickened, may explain some of the painful symptoms reported by patients and it is associated with a tendinopathy process, hence we suggest careful analysis in patients with Achillodynia.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Tendinopatia/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Tendão do Calcâneo/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Valores de Referência , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Tendinopatia/fisiopatologia , Adulto Jovem
12.
Cancer Gene Ther ; 22(1): 9-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25525036

RESUMO

The Cancer Stem Cells (CSCs) theory suggests that genetic alterations in stem cells are the direct cause for cancer. The evidence for a CSC population that results in pituitary tumors is poor. Some studies report the isolation of CSCs, but a deep characterization of the stemness of these cells is lacking. Here, we report the isolation and detailed characterization of progenitor mesenchymal cells (PMCs) from both growth hormone-secreting (GH(+)) and non-secreting (NS) pituitary adenomas, determining the immunophenotype, the expression of genes related to stemness or to pituitary hormone cell types, and the differentiative potential towards osteo-, chondro- and adipogenic lineages. Finally, the expression of CD133, known as a marker for CSCs in other tumors, was analyzed. Isolated cells, both from GH(+) and NS tumors, satisfy all the criteria for the identification of PMCs and express known stem cell markers (OCT4, SOX2, KLF4, NANOG), but do not express markers of pituitary hormone cell types (PITX2, PROP1, PIT1). Finally, PMCs express CD133. We demonstrated that pituitary tumors contain a stem cell population that can generate cell types characteristic of mesenchymal stem cells, and express CD133, which is associated with CSCs in other tumors.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Adulto , Idoso , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular , Movimento Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Feminino , Expressão Gênica , Humanos , Imunofenotipagem , Fator 4 Semelhante a Kruppel , Masculino , Células-Tronco Mesenquimais/patologia , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fenótipo , Neoplasias Hipofisárias/genética , RNA Mensageiro/genética
13.
J Bodyw Mov Ther ; 18(4): 588-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25440212

RESUMO

Despite their importance in anatomy, physiology, pathology and surgery, the fasciae and the fascial spaces have been poorly described in classic textbooks. This little attention depends on the fact that these fasciae vary in thickness and composition, especially at the cervical level. Indeed, in the main literature they have been described in different forms. Furthermore, the definition itself of the fascia is not consistent in a variety of authors. As a consequence, different criteria have been used to define and classify the fascial systems. In this paper, a brief terminological history and the most common nomenclatures and classifications of the fascia have been summarized.


Assuntos
Fáscia/anatomia & histologia , Perna (Membro) , Feminino , Humanos , Masculino
14.
Anal Bioanal Chem ; 405(2-3): 805-16, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22926126

RESUMO

Microbial colonization and biofilm formation on implanted devices represent an important complication in orthopaedic and dental surgery and may result in implant failure. Controlled release of antibacterial agents directly at the implant site may represent an effective approach to treat these chronic complications. Resistance to conventional antibiotics by pathogenic bacteria has emerged in recent years as a major problem of public health. In order to overcome this problem, non-conventional antimicrobial agents have been under investigation. In this study, polyacrylate-based hydrogel thin coatings have been electrosynthesised on titanium substrates starting from poly(ethylene glycol diacrylate)-co-acrylic acid. Silver nanoparticles (AgNPs) with a narrow size distribution have been synthesized using a "green" procedure and immobilized on Ti implant surfaces exploiting hydrogel coatings' swelling capabilities. The coatings have been characterized by XPS and SEM/EDX, while their silver release performances have been monitored by ICP-MS. The antibacterial activity of these AgNP-modified hydrogel coatings was tested evaluating in vitro inhibition growth of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, among the most common pathogens in orthopaedic infections. Moreover, a preliminary investigation of the biocompatibility of silver-loaded coatings versus MG63 human osteoblast-like cells has been performed. An important point of strength of this paper, in fact, is the concern about the effect of silver species on the surrounding cell system in implanted medical devices. Silver ion release has been properly tuned in order to assure antibacterial activity while preserving osteoblasts' response at the implant interface.


Assuntos
Antibacterianos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/prevenção & controle , Prata/farmacologia , Bactérias/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/análise , Formas de Dosagem , Contaminação de Equipamentos/prevenção & controle , Humanos , Bombas de Infusão Implantáveis , Nanopartículas/química , Infecções Relacionadas à Prótese/microbiologia , Titânio/química
15.
Mater Sci Eng C Mater Biol Appl ; 33(1): 28-36, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25428038

RESUMO

Bone TE uses a scaffold either to induce bone formation from surrounding tissue or to act as a carrier or template for implanted bone cells or other agents. We prepared different bone tissue constructs based on collagen, gelatin and hydroxyapatite using genipin as cross-linking agent. The fabricated construct did not present a release neither of collagen neither of genipin over its toxic level in the surrounding aqueous environment. Each scaffold has been mechanically characterized with compression, swelling and creep tests, and their respective viscoelastic mechanical models were derived. Mechanical characterization showed a practically elastic behavior of all samples and that compressive elastic modulus basically increases as content of HA increases, and it is strongly dependent on porosity and water content. Moreover, by considering that gradients in cellular and extracellular architecture as well as in mechanical properties are readily apparent in native tissues, we developed discrete functionally graded scaffolds (discrete FGSs) in order to mimic the graded structure of bone tissue. These new structures were mechanically characterized showing a marked anisotropy as the native bone tissue. Results obtained have shown FGSs could represent valid bone substitutes.


Assuntos
Osso e Ossos/fisiologia , Fenômenos Mecânicos , Alicerces Teciduais/química , Osso e Ossos/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colágeno/química , Força Compressiva/efeitos dos fármacos , Durapatita/química , Durapatita/farmacologia , Módulo de Elasticidade/efeitos dos fármacos , Humanos , Iridoides/química , Teste de Materiais , Fenômenos Mecânicos/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Porosidade , Espectrometria por Raios X
16.
J Biol Regul Homeost Agents ; 26(2 Suppl): 57-63, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23164328

RESUMO

Mesenchymal stem cells (MSCs) are of great interest for the regeneration of tissues and organs. Bone marrow is the first sources of MSCs, but in the recent years there has been interest in other tissues for the isolation of these pluripotent cells. In this study, we investigated the features of MSCs isolated from different oral regions in order to evaluate their potential application in the regeneration of damaged maxillofacial tissues. Sampling from human periodontal ligament, dental pulp, maxillary periosteum as well as bone marrow were collected in order to obtain different stem cell populations. Cells were morphologically and immunophenotipically characterized. Their proliferation potential and their ability to differentiate in osteoblasts were also assessed. All tested cell population showed a similar fibroblast-like morphology and superimposable immunophenotype. Slight differences were observed in proliferation and differentiation potential. Cells isolated from human periodontal ligament, dental pulp, maxillary periosteum had the characteristics of stem cells. Considering their peculiar feature they may alternatively represent interesting cell sources in stem cell-based bone/periodontal tissue regeneration approaches.


Assuntos
Células-Tronco Mesenquimais/citologia , Diferenciação Celular , Separação Celular , Células Cultivadas , Polpa Dentária/citologia , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/imunologia , Ligamento Periodontal/citologia , Periósteo/citologia
17.
J Biol Regul Homeost Agents ; 26(2 Suppl): 65-71, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23164329

RESUMO

Implant-associated infections represent an occasional but serious problem in dental and/or orthopaedic surgery. A possible solution to prevent the initial bacterial adhesion may be the coating of the implant surface with a thin layer of antibiotic-loaded biocompatible polymer. Hydrogels are one of the promising and versatile materials as antibiotic controlled release systems. In this work, antibiotic-modified poly(ethylene-glycol diacrylate) hydrogel coatings on titanium substrates were prepared by electrochemical polymerization and tested against methicillin resistant Staphylococcus aureus (ATCC 33591). Two different methods to load vancomycin and ceftriaxone were used. We show that the proposed titanium coatings displayed an interesting antibacterial activity, however, further studies on their effective cytotoxicity will furnish evidence of their real clinical efficacy.


Assuntos
Antibacterianos/farmacologia , Implantes Dentários , Hidrogel de Polietilenoglicol-Dimetacrilato/administração & dosagem , Antibacterianos/administração & dosagem , Cromatografia Líquida de Alta Pressão , Espectroscopia Fotoeletrônica , Titânio
18.
J Biol Regul Homeost Agents ; 26(3): 475-84, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23034267

RESUMO

Even though muscle injuries are very common, few scientific data on their effective treatment exist. Growth Factors (GFs) may have a role in accelerating muscle repair processes and a currently available strategy for their delivery into the lesion site is the use of autologous platelet-rich plasma (PRP). The present study is focused on the use of Platelet Rich Fibrin Matrix (PRFM), as a source of GFs. Bilateral muscular lesions were created on the longissimus dorsi muscle of Wistar rats. One side of the lesion was filled with a PRFM while the contralateral was left untreated (controls). Animals were sacrificed at 5, 10, 40 and 60 days from surgery. Histological, immunohistochemical and histomorphometric analyses were performed to evaluate muscle regeneration, neovascularization, fibrosis and inflammation. The presence of metaplasia zones, calcifications and heterotopic ossification were also assessed. PRFM treated muscles exhibited an improved muscular regeneration, an increase in neovascularization, and a slight reduction of fibrosis compared with controls. No differences were detected for inflammation. Metaplasia, ossification and heterotopic calcification were not detected. This preliminary morphological experimental study shows that PRFM use can improve muscle regeneration and long-term vascularization. Since autologous blood products are safe, PRFM may be a useful and handy product in clinical treatment of muscle injuries.


Assuntos
Fibrina/farmacologia , Músculo Esquelético/lesões , Neovascularização Fisiológica/efeitos dos fármacos , Plasma Rico em Plaquetas , Regeneração/efeitos dos fármacos , Animais , Masculino , Músculo Esquelético/patologia , Ratos , Ratos Wistar
19.
Stem Cell Rev Rep ; 8(3): 882-90, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22622690

RESUMO

Mesenchymal stem cells (MSCs) are promising tools for studying the mechanisms of development and for the regeneration of injured tissues. Correct selection of the MSCs source is crucial in order to obtain a more efficient treatment and, in this respect Periosteum-Derived Cells (PDPCs) may represent an interesting alternative to bone marrow MSCs for osteochondral tissue regeneration. In the present study we have isolated and characterized a MSCs population from the periosteum of human adult donors. PDPCs were expanded under specific culture conditions that prevent fibroblast contamination and support the maintenance of their undifferentiated phenotype. We show, for the first time, that PDPCs expresses VEGF receptor (Flt1 and KDR/Flk1) proteins and that they were similar to bone marrow Multipotent Adult Progenitor Cells (MAPCs). Since the latter are able to differentiate into endothelial cells, we tested the possible PDPCs commitment toward an endothelial phenotype in view of bone tissue engineering approaches that takes into account not only bone formation but also vascularization. PDPCs were treated with two different VEGF concentrations for 7 and 15 days and, alternatively, with the supernatant of human primary osteoblasts. Differently from MAPCs our PDPCs were unable to differentiate into endothelial cells after their in vitro VEGF treatment. On the contrary, growth factor stimulation induces PDPCs differentiation toward osteoblasts. We concluded that in PDPCs the presence of VEGF receptors is related to different cross-talk between osteogenesis and angiogenesis that could involve in situ PDPCs recruitment.


Assuntos
Células-Tronco Adultas/fisiologia , Periósteo/citologia , Engenharia Tecidual , Fator A de Crescimento do Endotélio Vascular/fisiologia , Adulto , Células-Tronco Adultas/metabolismo , Fosfatase Alcalina/metabolismo , Antígenos CD/metabolismo , Regeneração Óssea , Diferenciação Celular , Células Cultivadas , Células Endoteliais/metabolismo , Feminino , Humanos , Masculino , Fenótipo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo
20.
Acta Biomater ; 7(2): 882-91, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20659594

RESUMO

New promising and versatile materials for the development of in situ sustained release systems consisting of thin films of either poly(2-hydroxyethyl methacrylate) or a copolymer based on poly(ethylene-glycol diacrylate) and acrylic acid were investigated. These polymers were electrosynthesized directly on titanium substrates and loaded with ciprofloxacin (CIP) either during or after the synthesis step. X-ray photoelectron spectroscopy was used to check the CIP entrapment efficiency as well as its surface availability in the hydrogel films, while high-performance liquid chromatography was employed to assess the release property of the films and to quantify the amount of CIP released by the coatings. These systems were then tested to evaluate the in vitro inhibition of methicillin-resistant Staphylococcus aureus (MRSA) growth. Moreover, a model equation is proposed which can easily correlate the diameter of the inhibition haloes with the amount of antibiotic released. Finally, MG63 human osteoblast-like cells were employed to assess the biocompatibility of CIP-modified hydrogel coatings.


Assuntos
Ciprofloxacina/farmacologia , Materiais Revestidos Biocompatíveis/síntese química , Técnicas Eletroquímicas/métodos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Infecções Relacionadas à Prótese/prevenção & controle , Titânio/efeitos adversos , Antibacterianos/farmacologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Cinética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia de Fluorescência , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/ultraestrutura , Espectroscopia Fotoeletrônica , Infecções Relacionadas à Prótese/microbiologia
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