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1.
Acta Biomater ; 151: 501-511, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35933104

RESUMO

The osteogenic capability of mesoporous bioactive nanoparticles (MBNPs) in the SiO2CaO system has been assessed in vivo using an osteoporotic rabbit model. MBNPs have been prepared using a double template method, resulting in spherical nanoparticles with a porous core-shell structure that has a high surface area and the ability to incorporate the anti-osteoporotic drug ipriflavone. In vitro expression of the pro-inflammatory genes NF-κB1, IL-6, TNF-α, P38 and NOS2 in RAW-264.7 macrophages, indicates that these nanoparticles do not show adverse inflammatory effects. An injectable system has been prepared by suspending MBNPs in a hyaluronic acid-based hydrogel, which has been injected intraosseously into cavitary bone defects in osteoporotic rabbits. The histological analyses evidenced that MBNPs promote bone regeneration with a moderate inflammatory response. The incorporation of ipriflavone into these nanoparticles resulted in a higher presence of osteoblasts and enhanced angiogenesis at the defect site, but without showing significant differences in terms of new bone formation. STATEMENT OF SIGNIFICANCE: Mesoporous bioactive glass nanoparticles have emerged as one of the most interesting materials in the field of bone regeneration therapies. For the first time, injectable mesoporous bioactive nanoparticles have been tested in vivo using an osteoporotic animal model. Our findings evidence that MBG nanoparticles can be loaded with an antiosteoporotic drug, ipriflavone, and incorporated in hyaluronic acid to make up an injectable hydrogel. The incorporation of MBG nanoparticles promotes bone regeneration even under osteoporotic conditions, whereas the presence of IP enhances angiogenesis as well as the presence of osteoblast cells lining in the newly formed bone. The injectable device presented in this work opens new possibilities for the intraosseous treatment of osteoporotic bone using minimally invasive surgery.


Assuntos
Nanopartículas , Osteoporose , Animais , Regeneração Óssea , Osso e Ossos , Vidro/química , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Interleucina-6 , Nanopartículas/química , Nanopartículas/uso terapêutico , Osteogênese , Osteoporose/tratamento farmacológico , Porosidade , Coelhos , Alicerces Teciduais/química , Fator de Necrose Tumoral alfa/farmacologia
2.
Colloids Surf B Biointerfaces ; 208: 112110, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34555654

RESUMO

Mesoporous bioactive glasses (MBGs) are bioceramics designed to induce bone tissue regeneration and very useful materials with the ability to act as drug delivery systems. MBGs can be implanted in contact with bone tissue in different ways, as particulate material, in 3D scaffolds or as nanospheres. In this work, we assessed the effects of particles of mesoporous bioactive glass MBG-75S and mesoporous nanospheres NanoMBG-75S on RAW 264.7 and J774A.1 macrophages, which present different sensitivity and are considered as ideal models for the study of innate immune response. After evaluating several cellular parameters (morphology, size, complexity, proliferation, cell cycle and intracellular content of reactive oxygen species), the action of MBG-75S particles and NanoMBG-75S on the polarization of these macrophages towards the pro-inflammatory (M1) or reparative (M2) phenotype was determined by the expression of specific M1 (CD80) and M2 (CD206, CD163) markers. We previously measured the adsorption of albumin and fibrinogen on MBG-75S particles and the production of pro-inflammatory cytokines as TNF-α and IL-6 by macrophages in response to these particles. This comparative study demonstrates that particles of mesoporous bioactive glass MBG-75S and mesoporous nanospheres NanoMBG-75S allow the appropriated development and function of RAW 264.7 and J774A.1 macrophages and do not induce polarization towards the M1 pro-inflammatory phenotype. Therefore, considering that these mesoporous biomaterials offer the possibility of loading drugs into their pores, the results obtained indicate their high potential for use as drug-delivery systems in bone repair and osteoporosis treatments without triggering an adverse inflammatory response.


Assuntos
Vidro , Nanosferas , Proliferação de Células , Macrófagos , Porosidade , Alicerces Teciduais
3.
Int Immunopharmacol ; 94: 107457, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33752172

RESUMO

The use of nanoparticles for intracellular drug delivery could reduce the toxicity and side effects of the drug but, the uptake of these nanocarriers could induce adverse effects on cells and tissues after their incorporation. Macrophages play a central role in host defense and are responsible for in vivo nanoparticle trafficking. Assessment of their defense capacity against pathogenic micro-organisms after nanoparticle uptake, is necessary to prevent infections associated with nanoparticle therapies. In this study, the effects of hollow mesoporous SiO2-CaO nanospheres labeled with fluorescein isothiocyanate (FITC-NanoMBGs) on the function of peritoneal macrophages was assessed by measuring their ability to phagocytize Candidaalbicans expressing a red fluorescent protein. Two macrophage/fungus ratios (MOI1 and MOI5) were used and two experimental strategies were carried out: a) pretreatment of macrophages with FITC-NanoMBGs and subsequent fungal infection; b) competition assays after simultaneous addition of fungus and nanospheres. Macrophage pro-inflammatory phenotype markers (CD80 expression and interleukin 6 secretion) were also evaluated. Significant decreases of CD80+ macrophage percentage and interleukin 6 secretion were observed after 30 min, indicating that the simultaneous incorporation of NanoMBG and fungus favors the macrophage non-inflammatory phenotype. The present study evidences that the uptake of these nanospheres in all the studied conditions does not alter the macrophage function. Moreover, intracellular FITC-NanoMBGs induce a transitory increase of the fungal phagocytosis by macrophages at MOI 1 and after a short time of interaction. In the competition assays, as the intracellular fungus quantity increased, the intracellular FITC-NanoMBG content decreased in a MOI- and time-dependent manner. These results have confirmed that macrophages clearly distinguish between inert material and the live yeast in a dynamic intracellular incorporation. Furthermore, macrophage phagocytosis is a critical determinant to know their functional state and a valuable parameter to study the nanomaterial / macrophages / Candida albicans interface.


Assuntos
Compostos de Cálcio/administração & dosagem , Candida albicans , Macrófagos Peritoneais/efeitos dos fármacos , Nanosferas/administração & dosagem , Óxidos/administração & dosagem , Dióxido de Silício/administração & dosagem , Animais , Células Cultivadas , Macrófagos Peritoneais/fisiologia , Camundongos Endogâmicos C57BL , Porosidade
4.
Clin Exp Dermatol ; 46(2): 300-305, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32840927

RESUMO

BACKGROUND: Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a rare syndrome with characteristic skin lesions that are associated with fast-flow vascular malformations (FFVMs) in one-third of patients. Few case series have been described, and none in Spain. AIM: To identify the prevalence of dermatological parameters, FFVMs and associated features in a large series of patients with CM-AVM. METHODS: We conducted an observational study of patients with CM-AVM syndrome diagnosed in 15 Spanish hospitals over 3 years. The main clinical, radiological, genetic findings and associated diseases were analysed. RESULTS: In total, 64 patients were assessed. In 26.5% of cases, the diagnosis was incidental. In 75% of patients, there was one significantly larger macule, which we termed the 'herald patch'. FFVMs were detected in 34% of the patients, with 30% located on the skin, 7.8% in the brain and in 1.5% in the spine. There was a positive family history in 65% of the 64 patients. Genetic analysis was performed for RASA1 mutations in 57 patients, of whom 42 (73%) had a positive result. All 4 patients tested for EPHB4 mutations had a positive result. No tumour lesions were detected in the series, except for five infantile haemangiomas. CONCLUSIONS: Our data on clinical lesions, associated FFVM, family history and genetics are similar to those previously published in the literature. An extensive data analysis failed to demonstrate any statistically significant association between the presence of an FFVM and any clinical, familial or genetic parameter that could predict its onset, although a link between the presence of a herald patch on the midline face and the presence of a brain FFVM was observed. We did not detect any genotype-phenotype correlation.


Assuntos
Malformações Arteriovenosas/patologia , Encéfalo/patologia , Capilares/anormalidades , Mancha Vinho do Porto/patologia , Pele/patologia , Coluna Vertebral/patologia , Malformações Vasculares/patologia , Adulto , Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/epidemiologia , Malformações Arteriovenosas/genética , Encéfalo/irrigação sanguínea , Capilares/patologia , Criança , Pré-Escolar , Análise de Dados , Feminino , Estudos de Associação Genética , Humanos , Achados Incidentais , Lactente , Masculino , Mutação , Mancha Vinho do Porto/diagnóstico , Mancha Vinho do Porto/epidemiologia , Mancha Vinho do Porto/genética , Prevalência , Receptor EphB4/genética , Pele/irrigação sanguínea , Espanha/epidemiologia , Coluna Vertebral/irrigação sanguínea , Malformações Vasculares/diagnóstico , Malformações Vasculares/genética , Proteína p120 Ativadora de GTPase/genética
5.
Acta Biomater ; 101: 544-553, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678741

RESUMO

Silicon-substituted hydroxyapatite (SiHA) macroporous scaffolds have been prepared by robocasting. In order to optimize their bone regeneration properties, we have manufactured these scaffolds presenting different microstructures: nanocrystalline and crystalline. Moreover, their surfaces have been decorated with vascular endothelial growth factor (VEGF) to evaluate the potential coupling between vascularization and bone regeneration. In vitro cell culture tests evidence that nanocrystalline SiHA hinders pre-osteblast proliferation, whereas the presence of VEGF enhances the biological functions of both endothelial cells and pre-osteoblasts. The bone regeneration capability has been evaluated using an osteoporotic sheep model. In vivo observations strongly correlate with in vitro cell culture tests. Those scaffolds made of nanocrystalline SiHA were colonized by fibrous tissue, promoted inflammatory response and fostered osteoclast recruitment. These observations discard nanocystalline SiHA as a suitable material for bone regeneration purposes. On the contrary, those scaffolds made of crystalline SiHA and decorated with VEGF exhibited bone regeneration properties, with high ossification degree, thicker trabeculae and higher presence of osteoblasts and blood vessels. Considering these results, macroporous scaffolds made of SiHA and decorated with VEGF are suitable bone grafts for regeneration purposes, even in adverse pathological scenarios such as osteoporosis. STATEMENT OF SIGNIFICANCE: For the first time, the in vivo behavior of scaffolds made of silicon substituted hydroxyapatites (SiHA) has been evaluated under osteoporosis conditions. In order to optimize the bone regeneration properties of these bioceramics, 3D macroporous scaffolds have been manufactured by robocasting and implanted in osteoporotic sheep. Our experimental design shed light on the important issue of the biological response of nano-sized bioceramics vs highly crystalline bioceramics, as well as on the importance of coupling vascularization and bone growth processes by decorating SiHA scaffolds with vascular endothelial growth factor.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Durapatita/farmacologia , Osteoporose/patologia , Silício/farmacologia , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular/farmacologia , Adsorção , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/ultraestrutura , Feminino , Camundongos , Nanopartículas/química , Nanopartículas/ultraestrutura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoporose/diagnóstico por imagem , Porosidade , Ovinos , Suínos , Tomografia Computadorizada por Raios X
8.
Acta Biomater ; 83: 456-466, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30445158

RESUMO

The osteogenic and angiogenic responses to metal macroporous scaffolds coated with silicon substituted hydroxyapatite (SiHA) and decorated with vascular endothelial growth factor (VEGF) have been evaluated in vitro and in vivo. Ti6Al4V-ELI scaffolds were prepared by electron beam melting and subsequently coated with Ca10(PO4)5.6(SiO4)0.4(OH)1.6 following a dip coating method. In vitro studies demonstrated that SiHA stimulates the proliferation of MC3T3-E1 pre-osteoblastic cells, whereas the adsorption of VEGF stimulates the proliferation of EC2 mature endothelial cells. In vivo studies were carried out in an osteoporotic sheep model, evidencing that only the simultaneous presence of both components led to a significant increase of new tissue formation in osteoporotic bone. STATEMENT OF SIGNIFICANCE: Reconstruction of bones after severe trauma or tumors extirpation is one of the most challenging tasks in the field of orthopedic surgery. This scenario is even more complicated in the case of osteoporotic patients, since their bone regeneration capability is decreased. In this work we present a porous implant that promotes bone regeneration even in osteoporotic bone. By coating the implant with osteogenic bioceramics such as silicon substituted hydroxyapatite and subsequent adsorption of vascular endothelial growth factor, these implants stimulate the bone ingrowth when they are implanted in osteoporotic sheep.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Durapatita , Osteoporose , Silício , Titânio , Fator A de Crescimento do Endotélio Vascular , Ligas , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Durapatita/química , Durapatita/farmacologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Camundongos , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Osteoporose/patologia , Ovinos , Silício/química , Silício/farmacologia , Suínos , Titânio/química , Titânio/farmacologia , Fator A de Crescimento do Endotélio Vascular/química , Fator A de Crescimento do Endotélio Vascular/farmacologia
9.
Biomater Sci ; 6(11): 2987-2997, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30255874

RESUMO

Graphene-based materials are revealing a great promise for biomedical applications and demonstrating attractiveness for neural repair. In the context of neural tissue damage, the dialogue between neural and immune cells appears critical for driving regeneration, thus making the understanding of their relations pivotal. Herein, the acute response of RAW-264.7 macrophages on nanostructured reduced graphene oxide (rGO) microfibers has been evaluated through the analysis of cell parameters including proliferation, viability, intracellular content of reactive oxygen species, cell cycle, apoptosis, and cell size and complexity. The influence of the direct contact of rGO microfibers on their polarization towards M1 and M2 phenotypes has been studied by analyses of both M1 (CD80) and M2 (CD163) markers and the secretion of the inflammatory cytokines TNF-α and IL-6. Finally, the capability of these rGO microfibers to regulate neural stem cell differentiation has been also evaluated. Findings reveal that rGO microfibers inhibit the proliferation of RAW-264.7 macrophages without affecting their viability and cell cycle profiles. The presence of M1 and M2 macrophages on these microfibers was confirmed after 24 and 48 h, respectively, accompanied by a decrease in TNF-α and an increase in IL-6 cytokine secretion. These rGO microfibers were also able to support the formation of a highly interconnected neural culture composed of both neurons (map2+ cells) and glial cells (vimentin+ cells). These findings encourage further investigation of these microfibers as attractive biomaterials to interact with immune and neural cells, attempting to support wound healing and tissue repair after implantation.


Assuntos
Grafite/química , Grafite/farmacologia , Macrófagos/efeitos dos fármacos , Nanofibras/química , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Óxidos/química , Animais , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Interleucina-6/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Fenótipo , Células RAW 264.7 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
J Colloid Interface Sci ; 528: 309-320, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29859456

RESUMO

A mesoporous bioactive glass (MBG) of molar composition 75SiO2-20CaO-5P2O5 (MBG-75S) has been synthetized as a potential bioceramic for bone regeneration purposes. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), nitrogen adsorption studies and transmission electron microscopy (TEM) demonstrated that MBG-75S possess a highly ordered mesoporous structure with high surface area and porosity, which would explain the high ionic exchange rate (mainly calcium and silicon soluble species) with the surrounded media. MBG-75S showed high biocompatibility in contact with Saos-2 osteoblast-like cells. Concentrations up to 1 mg/ml did not lead to significant alterations on either morphology or cell cycle. Regarding the effects on osteoclasts, MBG-75S allowed the differentiation of RAW-264.7 macrophages into osteoclast-like cells but exhibiting a decreased resorptive activity. These results point out that MBG-75S does not inhibit osteoclastogenesis but reduces the osteoclast bone-resorbing capability. Finally, in vitro studies focused on the innate immune response, evidenced that MBG-75S allows the proliferation of macrophages without inducing their polarization towards the M1 pro-inflammatory phenotype. This in vitro behavior is indicative that MBG-75S would just induce the required innate immune response without further inflammatory complications under in vivo conditions. The overall behavior respect to osteoblasts, osteoclasts and macrophages, makes this MBG a very interesting candidate for bone grafting applications in osteoporotic patients.


Assuntos
Materiais Biocompatíveis/metabolismo , Cerâmica/metabolismo , Macrófagos/citologia , Osteoblastos/citologia , Osteoclastos/citologia , Animais , Apoptose , Ciclo Celular , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Tamanho Celular , Humanos , Macrófagos/metabolismo , Camundongos , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Porosidade , Células RAW 264.7
11.
J Colloid Interface Sci ; 512: 665-673, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29107917

RESUMO

Macrophages, as effector cells involved in the innate and adaptive immunity, play a key role in the response to nanomaterials as graphene oxide (GO) and in their cellular uptake. The interactions at the interface of GO nanosheets, macrophages and microbial pathogens need to be assessed to determine the possible impairment of the immune system induced by biomedical treatments with this nanomaterial. Here, we have evaluated by flow cytometry and confocal microscopy the ability of murine peritoneal macrophages to phagocytose the fungal pathogen Candida albicans, alive or heat-killed, after treatment with poly(ethylene glycol-amine)-derivatized GO nanosheets (PEG-GO). After GO treatment, differences in fungal phagocytosis were observed between macrophages that had taken up GO nanosheets (GO+ population) and those that had not (GO- population). GO treatment increased the ingested alive yeasts in GO- macrophages, whereas phagocytosis diminished in the GO+ population. Ingestion of heat-killed yeasts was slightly higher in both GO- and GO+ populations when comparing with control macrophages. For the first time, we show that GO uptake by macrophages modulates its phagocytic capability, affecting differentially the subsequent ingestion of either alive or heat-killed yeasts. Enhanced ingestion of heat-killed yeast by GO-treated macrophages suggests a beneficial role of this nanomaterial for the clearance of dead microorganisms during infection.


Assuntos
Candida albicans/imunologia , Grafite/química , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/microbiologia , Nanoestruturas/administração & dosagem , Fagocitose/imunologia , Animais , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Células Cultivadas , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Nanoestruturas/química , Fagocitose/efeitos dos fármacos
12.
Allergol. immunopatol ; 44(1): 83-95, ene.-feb. 2016. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-147488

RESUMO

Severe delayed drug-induced skin reactions in children are not common but potentially serious. This article describes aspects concerning the etiology, pathogenesis and clinical manifestations of these processes; it presents three paediatric cases, namely STS (Steven Johnson Syndrome), TEN (toxic epidermal necrolysis), probably related to amoxicillin/clavulanate and ibuprofen and DRESS (a drug reaction with eosinophilia and systemic symptoms) secondary to phenytoin; and in relation to them, the diagnosis and the treatment of these processes are discussed and reviewed. The AGEP (acute generalised exanthematous pustulosis) is also reviewed. The aetiological diagnosis of severe non-immediate reactions is difficult, and the value of current allergological testing is not well defined in these cases. Diagnosis is based on clinical history, the empirical risk of drugs to trigger SJS/TEN or DRESS, and the in vivo and in vitro testing of the suspect drug. Skin biopsy confirms that the clinical diagnosis and delayed hypersensitivity tests, especially the patch test and the lymphoblastic transformation test (LTT), may be important to confirm the aetiological diagnosis, in our cases emphasising the latter. These diseases can be life threatening (especially DRESS and TEN) and/or have a high rate of major complications or sequelae (SJS/TEN). The three cases described progressed well without sequelae. All were treated with corticosteroids, which is the most currently accepted treatment although the effect has not been clearly demonstrated


No disponible


Assuntos
Lactente , Criança , Humanos , Testes Cutâneos/métodos , Dermatite de Contato/complicações , Dermatite de Contato/diagnóstico , Dermatite de Contato/imunologia , Hipersensibilidade a Drogas/complicações , Hipersensibilidade a Drogas/imunologia , Sinusite/complicações , Sinusite/tratamento farmacológico , Hipersensibilidade Tardia/complicações , Hipersensibilidade Tardia/imunologia , Síndrome de Stevens-Johnson/complicações , Combinação Amoxicilina e Clavulanato de Potássio/efeitos adversos , Ibuprofeno/efeitos adversos
13.
J Colloid Interface Sci ; 461: 285-291, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26407056

RESUMO

HYPOTHESIS: Dental bleaching with H2O2 is a common daily practice in dentistry to correct discoloration of anterior teeth. The aim of this study has been to determine whether this treatment of human teeth affects growth, differentiation and activity of osteoclast-like cells, as well as the putative modulatory action of osteostatin and fibroblast growth factor 2 (FGF-2). EXPERIMENTS: Previously to the in vitro assays, structural, physical-chemical and morphological features of teeth after bleaching were studied. Osteoclast-like cells were cultured on human dentin disks, pre-treated or not with 38% H2O2 bleaching gel, in the presence or absence of osteostatin (100 nM) or FGF-2 (1 ng/ml). Cell proliferation and viability, intracellular content of reactive oxygen species (ROS), pro-inflammatory cytokine (IL-6 and TNFα) secretion and resorption activity were evaluated. FINDINGS: Bleaching treatment failed to affect either the structural or the chemical features of both enamel and dentin, except for slight morphological changes, increased porosity in the most superficial parts (enamel), and a moderate increase in the wettability degree. In this scenario, bleaching produced an increased osteoclast-like cell proliferation but decreased cell viability and cytokine secretion, while it augmented resorption activity on dentin. The presence of either osteostatin or FGF-2 reduced the osteoclast-like cell proliferation induced by bleaching. FGF-2 enhanced ROS content, whereas osteostatin decreased ROS but increased TNFα secretion. The bleaching effect on resorption activity was increased by osteostatin, but this effect was less evident with FGF-2. CONCLUSIONS: These findings further confirm the deleterious effects of tooth bleaching by affecting osteoclast growth and function as well as different modulatory actions of osteostatin and FGF-2.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Peróxido de Hidrogênio/farmacologia , Osteoclastos/efeitos dos fármacos , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Fragmentos de Peptídeos/metabolismo , Clareamento Dental/efeitos adversos , Adolescente , Adsorção , Adulto , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dentina/citologia , Dentina/efeitos dos fármacos , Dentina/metabolismo , Citometria de Fluxo , Humanos , Macrófagos/efeitos dos fármacos , Camundongos , Osteoclastos/citologia , Osteoclastos/metabolismo , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície , Molhabilidade , Adulto Jovem
14.
Allergol Immunopathol (Madr) ; 44(1): 83-95, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26089185

RESUMO

Severe delayed drug-induced skin reactions in children are not common but potentially serious. This article describes aspects concerning the etiology, pathogenesis and clinical manifestations of these processes; it presents three paediatric cases, namely STS (Steven Johnson Syndrome), TEN (toxic epidermal necrolysis), probably related to amoxicillin/clavulanate and ibuprofen and DRESS (a drug reaction with eosinophilia and systemic symptoms) secondary to phenytoin; and in relation to them, the diagnosis and the treatment of these processes are discussed and reviewed. The AGEP (acute generalised exanthematous pustulosis) is also reviewed. The aetiological diagnosis of severe non-immediate reactions is difficult, and the value of current allergological testing is not well defined in these cases. Diagnosis is based on clinical history, the empirical risk of drugs to trigger SJS/TEN or DRESS, and the in vivo and in vitro testing of the suspect drug. Skin biopsy confirms that the clinical diagnosis and delayed hypersensitivity tests, especially the patch test and the lymphoblastic transformation test (LTT), may be important to confirm the aetiological diagnosis, in our cases emphasising the latter. These diseases can be life threatening (especially DRESS and TEN) and/or have a high rate of major complications or sequelae (SJS/TEN). The three cases described progressed well without sequelae. All were treated with corticosteroids, which is the most currently accepted treatment although the effect has not been clearly demonstrated.


Assuntos
Síndrome de Hipersensibilidade a Medicamentos/diagnóstico , Hipersensibilidade Tardia/diagnóstico , Pele/imunologia , Síndrome de Stevens-Johnson/diagnóstico , Corticosteroides/uso terapêutico , Amoxicilina/administração & dosagem , Amoxicilina/efeitos adversos , Animais , Criança , Pré-Escolar , Ácido Clavulânico/administração & dosagem , Ácido Clavulânico/efeitos adversos , Síndrome de Hipersensibilidade a Medicamentos/tratamento farmacológico , Feminino , Humanos , Hipersensibilidade Tardia/tratamento farmacológico , Ibuprofeno/administração & dosagem , Ibuprofeno/efeitos adversos , Masculino , Fenitoína/administração & dosagem , Fenitoína/efeitos adversos , Pele/patologia , Síndrome de Stevens-Johnson/tratamento farmacológico , Resultado do Tratamento
15.
J Mater Chem B ; 4(11): 1951-1959, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263072

RESUMO

Silicon substituted and nanocrystalline hydroxyapatites have attracted the attention of many researchers due to their up-regulation in osteoblast cell metabolism and enhanced bioreactivity, respectively. On the other hand, the biomaterial success or failure depends ultimately on the immune response triggered after its implantation. Macrophages are the main components of the innate immune system with an important role in healing and tissue remodelling due to their remarkable functional plasticity, existing in a whole spectrum of functional populations with varying phenotypic features. The effects of nanocrystalline hydroxyapatite (nano-HA) and nanocrystalline silicon substituted hydroxyapatite (nano-SiHA) on the macrophage populations defined as pro-inflammatory (M1) and reparative (M2) phenotypes have been evaluated in the present study using RAW 264.7 cells and mouse peritoneal macrophages as in vitro models. M1 and M2 macrophage phenotypes were characterized by flow cytometry and confocal microscopy by the expression of CD80 and CD163, known as M1 and M2 markers, respectively. The polarization of primary macrophages towards the M1 or M2 phenotype was induced with the pro-inflammatory stimulus LPS or the anti-inflammatory stimulus IL-10, respectively, evaluating the biomaterial effects under these conditions. Our results show that both nano-HA and nano-SiHA favour the macrophage polarization towards an M2 reparative phenotype, decreasing M1 population and ensuring an appropriate response in the implantation site of these biomaterials designed for bone repair and bone tissue engineering.

16.
J Colloid Interface Sci ; 432: 221-8, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25086397

RESUMO

HYPOTHESIS: Graphene oxide (GO) has attracted the scientific community attention due to its novel properties and wide range of potential applications including hyperthermia cancer therapy. However, little is known about the GO effects on the immune function which involves both innate and adaptive defence mechanisms through the activation of different cell populations and secretion of several cytokines. The effect of different GO nanosheets designed for hyperthermia cancer therapy on macrophage and lymphocyte function should be determined before using GO for this application. EXPERIMENTS: The effects of GO nanosheets with 1 (1-GOs) and 6 arms (6-GOs) of polyethylene glycol on RAW-264.7 macrophages and primary splenocytes (as approximation to the in vivo situation) were evaluated through the proinflammatory cytokine secretion and the modulation of cell proliferation in the presence of specific stimuli for either T-lymphocytes (concanavalin A, anti-CD3 antibody) or B-lymphocytes/macrophages (lipopolysaccharide). FINDINGS: 6-GOs significantly increased the secretion of TNF-α by RAW-264.7 macrophages without alteration of IL-6 and IL-1ß levels. The treatment of primary splenocytes with 1-GOs and 6-GOs in the presence of concanavalin A, anti-CD3 antibody and lipopolysaccharide, produced significant dose-dependent decreases of cell proliferation and IL-6 levels, revealing weak inflammatory properties of GOs which are favourable for hyperthermia cancer therapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Grafite/farmacologia , Macrófagos/imunologia , Nanopartículas/química , Linfócitos T/imunologia , Animais , Linhagem Celular , Citocinas/imunologia , Grafite/química , Macrófagos/citologia , Camundongos , Baço/citologia , Baço/imunologia , Linfócitos T/citologia
17.
ACS Appl Mater Interfaces ; 6(16): 13697-706, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-24979758

RESUMO

Nano-graphene oxide (GO) has attracted great interest in nanomedicine due to its own intrinsic properties and its possible biomedical applications such as drug delivery, tissue engineering and hyperthermia cancer therapy. However, the toxicity of GO nanosheets is not yet well-known and it is necessary to understand its entry mechanisms into mammalian cells in order to avoid cell damage and human toxicity. In the present study, the cellular uptake of pegylated GO nanosheets of ca. 100 nm labeled with fluorescein isothiocyanate (FITC-PEG-GOs) has been evaluated in the presence of eight inhibitors (colchicine, wortmannin, amiloride, cytochalasin B, cytochalasin D, genistein, phenylarsine oxide and chlorpromazine) that specifically affect different endocytosis mechanisms. Three cell types were chosen for this study: human Saos-2 osteoblasts, human HepG2 hepatocytes and murine RAW-264.7 macrophages. The results show that different mechanisms take part in FITC-PEG-GOs uptake, depending on the characteristics of each cell type. However, macropinocytosis seems to be a general internalization process in the three cell lines analyzed. Besides macropinocytosis, FITC-PEG-GOs can enter through pathways dependent on microtubules in Saos-2 osteoblasts, and through clathrin-dependent mechanisms in HepG2 hepatocytes and RAW-264.7 macrophages. HepG2 cells can also phagocytize FITC-PEG-GOs. These findings help to understand the interactions at the interface of GO nanosheets and mammalian cells and must be considered in further studies focused on their use for biomedical applications.


Assuntos
Endocitose , Grafite/metabolismo , Hepatócitos/metabolismo , Macrófagos/metabolismo , Nanopartículas/química , Osteoblastos/metabolismo , Óxidos/metabolismo , Amilorida/farmacologia , Animais , Arsenicais/farmacologia , Células Cultivadas , Citocalasina B/farmacologia , Citocalasina D/farmacologia , Endocitose/efeitos dos fármacos , Fluoresceína-5-Isotiocianato/metabolismo , Genisteína/farmacologia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Nanopartículas/ultraestrutura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Polietilenoglicóis/metabolismo
18.
Nanotechnology ; 25(3): 035101, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24346084

RESUMO

Graphene oxide (GO) has been proposed as an hyperthermia agent for anticancer therapies due to its near-infrared (NIR) optical absorption ability which, with its small two-dimensional size, could have a unique performance when compared to that of any other nanoparticle. Nevertheless, attention should be given to the hyperthermia route and the kind of GO-cell interactions induced in the process. The hyperthermia laser irradiation parameters, such as exposure time and laser power, were investigated to control the temperature rise and consequent damage in the GOs containing cell culture medium. The type of cell damage produced was evaluated as a function of these parameters. The results showed that cell culture temperature (after irradiating cells with internalized GO) increases preferentially with laser power rather than with exposure time. Moreover, when laser power is increased, necrosis is the preferential cell death leading to an increase of cytokine release to the medium.


Assuntos
Morte Celular/efeitos dos fármacos , Citocinas/metabolismo , Grafite/farmacologia , Hipertermia Induzida/métodos , Nanopartículas , Morte Celular/imunologia , Linhagem Celular Tumoral , Tomografia com Microscopia Eletrônica , Humanos , Lasers , Microscopia Confocal , Osteoblastos , Óxidos
19.
Actas dermo-sifiliogr. (Ed. impr.) ; 104(10): 890-896, dic. 2013. mapa, graf, tab
Artigo em Inglês | IBECS | ID: ibc-117051

RESUMO

Antecedentes: No existen datos sobre la prevalencia de la epidermólisis ampollosa distrófica en España (EAD). La EAD es una enfermedad rara que conlleva una gran carga para el paciente que la sufre y para el sistema de salud que le atiende. Objetivo: Describir la prevalencia de la EAD en España. Métodos: Hemos empleado datos procedentes de 3 fuentes incompletas de pacientes: departamentos de Dermatología, 2 laboratorios de diagnóstico y la Asociación española de pacientes con epidermólisis ampollosa, DEBRA España, y los hemos combinado usando el método de captura-recaptura. Resultados: Hemos identificado 152 pacientes vivos. La prevalencia estimada de EAD fue de 6,0 casos por millón de habitantes (IC 95%: 4,2-11,8). La prevalencia en niños menores de 18 años fue de 15,3 por millón (IC 95%: 10,4-40,8). De acuerdo con el modelo de captura-recaptura el 77% no son seguidos en unidades de referencia, el 65% no tienen diagnóstico genético y el 76% no pertenecen a DEBRA. Conclusiones: La prevalencia de EAD en España es de 6,0 pacientes por millón de habitantes (IC 95%: 4,2 a 11,8), un número mayor que el estimado en otras zonas del mundo, pero similar a otros encontrados en otros países del Sur de Europa. Este resultado puede ser debido a auténticas variaciones geográficas, o a que los otros registros recogen un número incompleto de casos. La mayoría de los pacientes no son seguidos en unidades de referencia, no tienen diagnóstico genético y no son miembros de la asociación de pacientes, lo cual quiere decir que su situación sociosanitaria es muy mejorable (AU)


Background: Dystrophic epidermolysis bullosa (DEB) is a rare disease that represents a heavy burden for both the patient and the health care system. There are currently no data on the prevalence of DEB in Spain. Objective: To determine the prevalence of DEB in Spain. Methods: We used data from 3 incomplete population-based sources (hospital dermatology departments, diagnostic laboratories performing antigenic mapping, genetic testing or both, and the Spanish Association of Epidermolysis Bullosa Patients [DEBRA]) and combined them using the 3-source capture–recapture methodology. Results: We identified 152 living DEB patients. The estimated prevalence of DEB was 6.0 cases per million (95% CI, 4.2–11.8) in adults and 15.3 (95% CI, 10.4–40.8) in children under 18 years of age. The data indicated that 77% of the patients were not being followed up in specialized centers of reference; 65% had not had a genetic diagnosis, and 76% were not members of DEBRA. Conclusions: The prevalence of DEB in Spain is 6.0 patients per million (95% CI, 4.2–11.8), a figure higher than previous estimates in many areas, but similar to those found in other southern Europe countries. The north–south difference may represent real geographic differences in prevalence, but it might be due to the fact that most of the data come from registries with a lower than expected catchment. Many patients are not being followed up in centers of reference, do not have genetic diagnosis, and are not members of patients’ associations, suggesting that there is room for considerable improvement in their care (AU)


Assuntos
Humanos , Epidermólise Bolhosa Distrófica/epidemiologia , Melhoramento Biomédico , Estudos Transversais , Distribuição por Idade e Sexo , Espanha/epidemiologia
20.
Actas Dermosifiliogr ; 104(10): 890-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23809583

RESUMO

BACKGROUND: Dystrophic epidermolysis bullosa (DEB) is a rare disease that represents a heavy burden for both the patient and the health care system. There are currently no data on the prevalence of DEB in Spain. OBJECTIVE: To determine the prevalence of DEB in Spain. METHODS: We used data from 3 incomplete population-based sources (hospital dermatology departments, diagnostic laboratories performing antigenic mapping, genetic testing or both, and the Spanish Association of Epidermolysis Bullosa Patients [DEBRA]) and combined them using the 3-source capture-recapture methodology. RESULTS: We identified 152 living DEB patients. The estimated prevalence of DEB was 6.0 cases per million (95% CI, 4.2-11.8) in adults and 15.3 (95% CI, 10.4-40.8) in children under 18 years of age. The data indicated that 77% of the patients were not being followed up in specialized centers of reference; 65% had not had a genetic diagnosis, and 76% were not members of DEBRA. CONCLUSIONS: The prevalence of DEB in Spain is 6.0 patients per million (95% CI, 4.2-11.8), a figure higher than previous estimates in many areas, but similar to those found in other southern Europe countries. The north-south difference may represent real geographic differences in prevalence, but it might be due to the fact that most of the data come from registries with a lower than expected catchment. Many patients are not being followed up in centers of reference, do not have genetic diagnosis, and are not members of patients' associations, suggesting that there is room for considerable improvement in their care.


Assuntos
Epidermólise Bolhosa Distrófica/epidemiologia , Epidermólise Bolhosa Distrófica/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Humanos , Lactente , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Melhoria de Qualidade , Espanha/epidemiologia , Adulto Jovem
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