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1.
Waste Manag ; 137: 61-71, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34741823

RESUMO

The density, colour and texture, plus mineral and chemical features of 18 ceramic-like CDW samples from the Abruzzo region (Central Italy) were characterised. The concretes, natural stones, tiles, roof-tiles, bricks and perforated bricks are either aphanitic to porphyric. Concretes and natural stones are grey to white and tend to be > 2.0 g/cm3; the masonries are brown to reddish and close to < 2.0 g/cm3. Concrete and natural stone are rich or even exclusively made up of calcite, with high amounts of CaO (>40 wt%) and LOI (volatiles, CO2 + H2O). The masonries are instead calcite-, CaO- (<25 wt%) and LOI-poor (<8 wt%) but enriched in SiO2 (45 to 70 wt%) stabilised as quartz and/or cristobalite, with significant amount of Al2O3 (12 to 20 wt%). S and Cl contents are similar among concrete, bricks and perforated bricks. The petrography of CDW concretes is similar among geographical areas with abundance of limestones used as aggregates. However, in limestone-poor areas CDW are SiO2- and Al2O3-rich, reflecting the prevalent use of masonry and/or silicate-rich construction materials, implying that each geographical area is characterised by peculiar CDW composition. Therefore, the knowledge of mesoscopic, physical and petrographic aspects has to be known for planning adequate sorting methods, promoting upcycling reusing applications. Some of the studied CDW samples are susceptible to release relative high Cr and As content.


Assuntos
Indústria da Construção , Gerenciamento de Resíduos , Materiais de Construção , Resíduos Industriais/análise , Itália , Reciclagem , Dióxido de Silício
2.
J Photochem Photobiol B ; 205: 111826, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32146270

RESUMO

Antibiotic resistance is a major public health problem worldwide and the finding of alternative methods for eliminating bacteria is one of the prerogatives of medical research. The indiscriminate use of antibiotics in dentistry, especially for the treatment of peri-implantitis, could lead to superinfections. Alternative methods, like photodynamic therapy mediated by the use of aminolevulinic acid and a red light has been largely described, especially in dentistry, but results were encouraging against Gram-positive bacteria, but limited against Gram-negative. The effectiveness of photodynamic therapy mediated by a novel product containing aminolevulinic acid, Aladent (ALAD) has been tested in this in vitro study, against different types of bacteria particularly involved in the infections of the oral cavity and peri-implantitis. The novelty of ALAD is the marked hydrophilicity that should increase the passage of the molecule through the membrane pores of Gram-negative bacteria. Considering the novelty of the product a preliminary experiment permitted to test the effectiveness against Enterococcus faecalis after 1 h of ALAD incubation at different concentrations, with or without different timings of LED irradiation. The count of CFUs and the live/dead observation with fluorescent microscopy showed a significant reduction and killing of bacterium. Then, in the second stage, that could meet the necessity of effectiveness and the clinician's requests to reduce the timing of treatment, ALAD, with and without irradiation, was tested on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Veillonella parvula and Porphyromonas gingivalis. In particular, the efficiency of different concentrations of the product after a 25 min incubation was tested with and without the adjunctive LED irradiation for 5 min. A slight ALAD bactericidal effect was reported for all bacteria, also without LED irradiation, however, the most effective treatment was 25 min of 50% ALAD incubation followed by 5 min of a red LED. The in vitro tests demonstrated that ALAD gel with LED irradiation exerts a potent antibacterial activity on different bacteria, both Gram-positive and Gram-negative.


Assuntos
Ácido Aminolevulínico/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos da radiação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos da radiação , Luz , Fármacos Fotossensibilizantes/farmacologia , Infecções Bacterianas/tratamento farmacológico , Géis , Peri-Implantite/tratamento farmacológico , Fotoquimioterapia
3.
Aust Dent J ; 63(2): 231-241, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29509293

RESUMO

BACKGROUND: The aim of this study was to investigate for the first time the histological response of human periodontium to mineral trioxide aggregate (MTA) and Biodentine. METHODS: Six patients scheduled for implant full-arch rehabilitation were randomly assigned to one of the two test groups: MTA or Biodentine treatment. For each patient, two teeth scheduled for strategic extraction were randomly assigned either to the test or to the control treatment. A lateral perforation was drilled on the root and either repaired with MTA/Biodentine or filled with gutta-percha(control). Three months later, the teeth were extracted along with the coronal third of the alveolar bone and a portion of gingival tissue, while performing implant placement, and processed for histological analysis. RESULTS: Biodentine resulted in less extrusion into the periodontal environment. All the materials showed good biocompatibility. A new mineralized cementum-like tissue incorporating periodontal fibres was visible in all cases treated with MTA. A small amount of new mineralized tissue was found in two Biodentine cases but not in control cases. Biodentine resulted in less damage to the periodontal ligament. CONCLUSIONS: Bioactivity and biocompatibility of MTA were confirmed in human models. Biodentine proved to be biocompatible, but it seems not to induce cementum regeneration.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Dentina/química , Óxidos/farmacologia , Ligamento Periodontal/efeitos dos fármacos , Periodonto/efeitos dos fármacos , Silicatos/farmacologia , Idoso , Materiais Biocompatíveis , Estudos de Casos e Controles , Combinação de Medicamentos , Feminino , Gengiva/efeitos dos fármacos , Guta-Percha , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória , Projetos Piloto , Método Simples-Cego , Dente/efeitos dos fármacos
4.
Oral Implantol (Rome) ; 10(3): 241-246, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29285326

RESUMO

The histological and histomorphometrical examination were the gold standard in the qualitative and quantitative analyses of the peri-implant tissue around the implant. In recent years, the field of microscopy has witnessed a considerable enhancement of the performance of microscopes that have very high resolution performance and allowing very sophisticated analysis even larger than traditional preparations. The possibility to have an affordable analyses of whole implant with the surrounding different tissues (soft and hard tissues) without the traditional pre-treatment necessary for the histological analysis may represent a goal to describe material properties and behaviors or simply to visualize structural details. The aim of the present study were to evaluate a 3D X-ray microscopic analysis of peri-implant tissue compared to a traditional histological and histomorphometrical analysis of the peri-implant tissues around an implant with a conical connection associated with platform-switching in order to assess the validity of the new analysis technique.

6.
Cell Oncol (Dordr) ; 40(6): 609-619, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28936810

RESUMO

BACKGROUND: The CXCL12-CXCR4 chemokine axis plays an important role in cell trafficking as well as in tumor progression. In colorectal cancer (CRC), the chemokine receptor CXCR4 has been shown to be an unfavorable prognostic factor in some studies, however, the role of its activated (phosphorylated) form, pCXCR4, has not yet been evaluated. Here, we aimed to investigate the prognostic value of CXCR4 and pCXCR4 in a large cohort of CRC patients. PATIENTS AND METHODS: A tissue microarray (TMA) of 684 patient specimens of primary CRCs was analyzed by immunohistochemistry (IHC) for the expression of CXCR4 and pCXCR4 by tumor cells and tumor-infiltrating immune cells (TICs). RESULTS: The combined high expression of CXCR4 and pCXCR4 showed a favorable 5-year overall survival rate (68%; 95%CI = 59-76%) compared to tumors showing a high expression of CXCR4 only (48%; 95%CI = 41-54%). High expression of pCXCR4 was significantly associated with a favorable prognosis in a test and validation group (p = 0.015 and p = 0.0001). Moreover, we found that CRCs with a high density of pCXCR4+ tumor-infiltrating immune cells (TICs) also showed a favorable prognosis in a test and validation group (p = 0.054 and p = 0.004). Univariate Cox regression analysis for TICs revealed that a high density of pCXCR4+ TICs was a favorable prognostic marker for overall survival (HR = 0.97,95%CI = 0.96-1.00; p = 0.01). In multivariate Cox regression survival analyses a high expression of pCXCR4 in tumor cells lost its association with a better overall survival (HR = 0.99; 95%CI = 0.99-1.00, p = 0.098). CONCLUSION: Our results show that high densities of CXCR4 and pCXCR4 positive TICs are favorable prognostic factors in CRC.


Assuntos
Neoplasias Colorretais/metabolismo , Receptores CXCR4/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Intervalos de Confiança , Humanos , Imuno-Histoquímica , Fosforilação/genética , Fosforilação/fisiologia , Modelos de Riscos Proporcionais , Receptores CXCR4/genética , Estudos Retrospectivos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Software , Taxa de Sobrevida , Análise Serial de Tecidos
7.
Dent Mater ; 33(5): e221-e238, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28233601

RESUMO

OBJECTIVE: To study the in vivo osteoinductive potential, bone-bonding ability (bioactivity) and bone biomineralization of current hydraulic calcium silicate cements used as graft materials and placed in contact with medullary bone. METHODS: ProRoot MTA, MTA Plus and Biodentine were used to fill surgical bone defects (2-mm diameter through the entire cortical thickness to reach the medullary bone) in the tibia of mature male rabbits. Tibiae were retrieved after 30days and submitted to histological analysis and microchemical characterization using Optical Microscopy (OM) and Environmental Scanning Electron Microscopy with Energy Dispersive X-ray analysis (ESEM-EDX). Bone neoformation and histomorphometric evaluations, degree of mineralization (by Ca/P, Ca/N and P/N ratios) and the diffusion of material elements were studied. RESULTS: Bone neoformation was observed in response to all materials. No sign of necrosis were found on the walls of the pre-existing cortical bone. No osteoclasts and no formation of fibrous tissue were evident. Sign of angiogenesis were present. EDX (element content, line profile and element mapping) showed the increase in Ca and P and decrease in C, S and N from the mature bone towards the mineralizing interface. Ca/P, Ca/N and P/N ratios showed differences in the degree of mineralization/maturation stage of bone. MTA Plus and ProRoot MTA exhibited close contact with the pre-existing bone and good bone-bonding with neoformed bone juxtaposed on the medullary side of the materials without interposed connective tissue or resorption lacunae or gaps. The materials showed a dense appearance with 100% of residual materials and no colonization by fluids and cells. No migration of Bi or Al material elements to the newly formed bone was found. Biodentine showed newly formed trabecular bone with marrow spaces and sparse traces of residual material (≈9%). SIGNIFICANCE: The in vivo osteoinductive properties with dynamic biomineralization processes around these calcium silicate materials extruded in medullary bone in appropriate animal model have been demonstrated by ESEM-EDX in association with OM. Good biocompatibility was evident as only slight inflammatory infiltrate and no sign of necrosis at the interface with the pre-existing bone were found. MTA Plus and ProRoot MTA exhibited bioactive potential as they can bond to bone directly without interposed connective tissue. Biodentine was replaced by newly formed bone. CLINICAL SIGNIFICANCE: The results of the study demonstrate the capacity of calcium silicate cements to allow osteoid matrix deposition by activated osteoblasts and favour its biomineralization, and to achieve a direct bond between the (bioactive) materials surface and the mineralized bone matrix.


Assuntos
Desenvolvimento Ósseo , Materiais Restauradores do Canal Radicular , Compostos de Alumínio , Animais , Compostos de Cálcio , Combinação de Medicamentos , Teste de Materiais , Óxidos , Pemetrexede , Coelhos , Silicatos
8.
Gut ; 66(4): 692-704, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-26719303

RESUMO

BACKGROUND: The immune contexture predicts prognosis in human colorectal cancer (CRC). Whereas tumour-infiltrating CD8+ T cells and myeloid CD16+ myeloperoxidase (MPO)+ cells are associated with favourable clinical outcome, interleukin (IL)-17-producing cells have been reported to correlate with severe prognosis. However, their phenotypes and functions continue to be debated. OBJECTIVE: To investigate clinical relevance, phenotypes and functional features of CRC-infiltrating, IL-17-producing cells. METHODS: IL-17 staining was performed by immunohistochemistry on a tissue microarray including 1148 CRCs. Phenotypes of IL-17-producing cells were evaluated by flow cytometry on cell suspensions obtained by enzymatic digestion of clinical specimens. Functions of CRC-isolated, IL-17-producing cells were assessed by in vitro and in vivo experiments. RESULTS: IL-17+ infiltrates were not themselves predictive of an unfavourable clinical outcome, but correlated with infiltration by CD8+ T cells and CD16+ MPO+ neutrophils. Ex vivo analysis showed that tumour-infiltrating IL-17+ cells mostly consist of CD4+ T helper 17 (Th17) cells with multifaceted properties. Indeed, owing to IL-17 secretion, CRC-derived Th17 triggered the release of protumorigenic factors by tumour and tumour-associated stroma. However, on the other hand, they favoured recruitment of beneficial neutrophils through IL-8 secretion and, most importantly, they drove highly cytotoxic CCR5+CCR6+CD8+ T cells into tumour tissue, through CCL5 and CCL20 release. Consistent with these findings, the presence of intraepithelial, but not of stromal Th17 cells, positively correlated with improved survival. CONCLUSIONS: Our study shows the dual role played by tumour-infiltrating Th17 in CRC, thus advising caution when developing new IL-17/Th17 targeted treatments.


Assuntos
Neoplasias Colorretais/imunologia , Interleucina-17/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Células Th17/imunologia , Células Th17/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , Quimiocina CCL20/metabolismo , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Quimiocina CXCL10/genética , Quimiocina CXCL9/genética , Neoplasias Colorretais/patologia , Feminino , Células HT29 , Humanos , Interleucina-17/análise , Interleucina-17/genética , Interleucina-8/metabolismo , Linfócitos do Interstício Tumoral/química , Masculino , Pessoa de Meia-Idade , Neutrófilos/química , Neutrófilos/enzimologia , Neutrófilos/imunologia , Peroxidase/análise , Fenótipo , Prognóstico , Receptores de IgG/análise , Taxa de Sobrevida , Linfócitos T Citotóxicos/imunologia , Células Th17/química
9.
Microsc Microanal ; 21(1): 190-203, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25667970

RESUMO

The creation of micro-textured dental implant surfaces possessing a stimulating activity represents a challenge in implant dentistry; particularly, the formation of a thin, biologically active, calcium-phosphate layer on their surface could help to strengthen the bond to the surrounding bone. The aim of the present study was to characterize in terms of macrostructure, micro-topography and reactivity in simulated body fluid (SBF), the surface of titanium (Ti) implants blasted with TiO2 particles, acid etched with hydrofluoric acid, and activated with Ca and Mg-containing nanoparticles. Sandblasted and acid-etched implants were analyzed by ESEM-EDX (environmental scanning electron microscope with energy dispersive X-ray system) to study the micromorphology of the surface and to perform elemental X-ray microanalysis (microchemical analyses) and element mapping. ESEM-EDX analyses were performed at time 0 and after a 28-day soaking period in SBF Hank's balanced salt solution (HBSS) following ISO 23317 (implants for surgery­in vitro evaluation for apatite-forming ability of implant materials). Microchemical analyses (weight % and atomic %) and element mapping were carried out to evaluate the relative element content, element distribution, and calcium/phosphorus (Ca/P) atomic ratio. Raman spectroscopy was used to assess the possible presence of impurities due to manufacturing and to investigate the phases formed upon HBSS soaking. Micro-morphological analyses showed a micro-textured, highly rough surface with microgrooves. Microchemical analyses showed compositional differences among the apical, middle, and distal thirds. The micro-Raman analyses of the as-received implant showed the presence of amorphous Ti oxide and traces of anatase, calcite, and a carbonaceous material derived from the decomposition of an organic component of lipidic nature (presumably used as lubricant). A uniform layer of Ca-poor calcium phosphates (CaPs) (Ca/P ratio <1.47) was observed after soaking in HBSS; the detection of the 961 cm⁻¹ Raman band confirms this finding. These implants showed a micro-textured surface supporting the formation of CaPs when immersed in SBF. These properties may likely favor bone anchorage and healing by stimulation of mineralizing cells.


Assuntos
Líquidos Corporais/química , Implantes Dentários , Materiais Dentários/química , Fosfatos de Cálcio/química , Microanálise por Sonda Eletrônica , Humanos , Teste de Materiais , Modelos Biológicos , Propriedades de Superfície , Titânio/química
10.
Minerva Stomatol ; 63(10): 351-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25503094

RESUMO

AIM: A variety of surgical techniques have been developed to reconstruct the posterior maxilla when bone volume is insufficient. For some decades, sinus augmentation, using various bone substitutes, has been used to reconstruct the posterior maxilla for dental implant placement. Even if new bone formation is achieved in the sinus after bone grafting, the possibility of new bone formation with only a membrane elevation in the maxillary sinus has been reported in human and animal studies. The aim of this case report was to document an unexpected healing pattern after the removal of a dental implant migrated in the maxillary sinus. METHODS: In October 2009 a 49-year-old man with a partially edentulous maxilla underwent implant placement. Specifically, a total of 5 implants were inserted, 2 in the left and 3 in the right posterior maxilla. Four months later, at the time of abutment connection, the implant at the site of the maxillary left first molar was accidentally pushed in the sinus. A surgical removal of the implant from the maxillary sinus was proposed and the patient consented to the surgical intervention. Computed axial tomography (CAT) scan images revealed opacification of the left maxillary sinus with mucosal thickening, and the dental implant displaced within the sinus. The planned treatment sequence was: 1) removal of the implant; 2) sinus augmentation procedure after 5 months; 3) implant insertion 5 months after the bone graft. The implant was removed. Five months later, the patient was admitted for the bone-grafting augmentation procedure. A new CAT scan image revealed normal mucosal thickness and no opacification of the left maxillary sinus; bone formation was evident. The surgery was undertaken with local anesthesia and conscious sedation. RESULTS: At reentry, the sinus wall was found to be totally healed. Newly formed bone (21.2%) with wide osteocyte lacunae and large marrow spaces (73.8%) were present with newly formed vessels and no inflammatory cell infiltrate. CONCLUSION: The surgical trauma and the creation of a secluded space between the bone surfaces and the healed sinus mucosa resulted in a spontaneous bone formation in the maxillary sinus. The surgical approach described may be used to achieve bone formation to enable placement of dental implants without the addition of any grafting material.


Assuntos
Transplante Ósseo , Implantes Dentários/efeitos adversos , Migração de Corpo Estranho/cirurgia , Maxila/cirurgia , Osteogênese , Remoção de Dispositivo , Humanos , Masculino , Seio Maxilar , Pessoa de Meia-Idade , Falha de Prótese
11.
Thromb Haemost ; 112(6): 1219-29, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25209750

RESUMO

Accumulating evidence suggests an immune-modulatory role for platelets (PLT) and PLT-derived microvesicles. In particular, ectosomes, i.e. vesicles budding from PLT surface, have been shown to exert immunosuppressive activities on phagocytes. Here we investigated the effects mediated by PLT-derived ectosomes (PLT-Ecto) on CD4+ T cells. Exposure of activated CD4+ T cells to PLT-Ecto decreased their release of IFNγ, TNFα and IL-6, and increased the production of TGF-ß1. Concomitantly, PLT-Ecto-exposed CD4+ T cells displayed increased frequencies of CD25high Foxp3+ cells. These phenomena were dose-dependent and PLT-Ecto specific, since they were not observed in the presence of polymorphonuclear- and erythrocyte-derived ectosomes. Analysis of specific T cell subsets revealed that PLT-Ecto induced differentiation of naïve T cells into Foxp3+ cells, but had no effect on pre-differentiated Foxp3+ regulatory T cells (Tregs). Importantly, PLT-Ecto-induced Foxp3+ cells were as effective as peripheral blood Tregs in suppressing CD8+ T cell proliferation. PLT-Ecto-mediated effects were partly dependent on PLT-derived TGF-ß1, as they were to some extent inhibited by PLT-Ecto pretreatment with TGF-ß1-neutralising antibodies. Interestingly, ectosome-derived TGF-ß1 levels correlated with Foxp3+ T cell frequencies in blood of healthy donors. In conclusion, PLT-Ecto induce differentiation of CD4+ T cells towards functional Tregs. This may represent a mechanism by which PLT-Ecto enhance peripheral tolerance.


Assuntos
Plaquetas/metabolismo , Diferenciação Celular , Micropartículas Derivadas de Células/metabolismo , Comunicação Parácrina , Linfócitos T Reguladores/metabolismo , Plaquetas/imunologia , Linfócitos T CD8-Positivos , Proliferação de Células , Micropartículas Derivadas de Células/imunologia , Células Cultivadas , Técnicas de Cocultura , Fatores de Transcrição Forkhead/metabolismo , Humanos , Tolerância Imunológica , Interferon gama/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Fatores de Tempo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Biomed Res Int ; 2013: 549762, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24073409

RESUMO

PURPOSE: This study evaluated the efficacy of a regenerative approach using mesenchymal stem cells (MSCs) and CAD-CAM customized pure and porous hydroxyapatite (HA) scaffolds to replace the temporomandibular joint (TMJ) condyle. METHODS: Pure HA scaffolds with a 70% total porosity volume were prototyped using CAD-CAM technology to replace the two temporomandibular condyles (left and right) of the same animal. MSCs were derived from the aspirated iliac crest bone marrow, and platelets were obtained from the venous blood of the sheep. Custom-made surgical guides were created by direct metal laser sintering and were used to export the virtual planning of the bone cut lines into the surgical environment. Sheep were sacrificed 4 months postoperatively. The HA scaffolds were explanted, histological specimens were prepared, and histomorphometric analysis was performed. RESULTS: Analysis of the porosity reduction for apposition of newly formed bone showed a statistically significant difference in bone formation between condyles loaded with MSC and condyles without (P < 0.05). The bone ingrowth (BI) relative values of split-mouth comparison (right versus left side) showed a significant difference between condyles with and without MSCs (P < 0.05). Analysis of the test and control sides in the same animal using a split-mouth study design was performed; the condyle with MSCs showed greater bone formation. CONCLUSION: The split-mouth design confirmed an increment of bone regeneration into the HA scaffold of up to 797% upon application of MSCs.


Assuntos
Plaquetas/química , Cerâmica/farmacologia , Desenho Assistido por Computador , Durapatita/farmacologia , Côndilo Mandibular/fisiologia , Células-Tronco Mesenquimais/citologia , Alicerces Teciduais/química , Animais , Cartilagem/citologia , Cartilagem/efeitos dos fármacos , Géis , Côndilo Mandibular/efeitos dos fármacos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Porosidade , Ovinos , Engenharia Tecidual
13.
Case Rep Dent ; 2013: 828373, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24027644

RESUMO

Benign cementoblastoma is a rare ectomesenchymal odontogenic tumor that originates from the root of the tooth and that is characterized by the formation of cementum-like tissue. A 60-year old man was referred to us complaining of pain in his right jaw. The patient underwent TC dental scan of the mandible, which highlighted the presence of three well-circumscribed, round, unilocular neoformations of radiopaque appearance with a radiotransparent edge, one of which was in close contact with the roots of the lower right second molar. Microscopic examination of the greater sample consisted, in its central portion, of dense mineralized acellular trabeculae of basophilic tissue cement-like, devoid of vessels, adhering to the root of the tooth, while peripherally was observed a zone of vascularized osteoid surrounded, occasionally, by a thin rim of cementoblasts mixed with fibrous tissue and inflammatory elements. This lesion was diagnosed as cementoblastoma. The second lesion appeared radiologically and histologically entirely identical to cementoblastoma, but it did not show the intimate association with the root of involved tooth. After a careful review of the literature, the diagnosis of residual cementoblastoma was made. The clinicopathologic features, treatment, and prognosis of this rare tumor are here discussed for the young dental practitioner.

14.
J Biol Regul Homeost Agents ; 26(2 Suppl): 19-28, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23164323

RESUMO

BACKGROUND: The biological fixation of an implant to bone is influenced by numerous factors, including surface chemistry and surface topography. Various methods have been developed to create rough implant surfaces in order to improve the clinical performance of implants and to guarantee a stable mechanical bone-implant interface. Anodic oxidation is a dental implant surface modification technique that results in oxide layer growth up to a thickness of 1–10 micron. The purpose of this study was to evaluate the performance of the surface through the osteoblasts cells growth and the influence of oxidixed surface on BIC percent, in the human posterior maxilla after 2 months of unloaded healing. MATERIAL AND METHODS: In vitro commercially available primary human osteoblasts (NHOst) from both femur and tibia of different donor systems (Lonza Walkersville Inc, Walkersville, MD, USA) were grown in Osteoblast Growth Media (OBM) (Lonza). Osteogenic differentiation was induced for a period of 4 weeks by the OGM medium (OBM basal medium supplemented with 200nM of hydrocortisone-21-hemisuccinate and 7.5 mM of glycerophosphate). The viability of NHOst cells seeded test A and B was measured by the quantitative colorimetric MTT (3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2Htetrazoliumbromide test) (Promega, Milan, Italy). One custom-made 2 x 10-mm site evaluation implant (SEI) with nanometer scale and oxidized surface (test) ( Evo Plan 1 Health s.r.l. - Amaro, UD, Italy), and one SEI with hydroxyapatite sandblasted surface (control) (Osseogrip Plan 1 Health s.r.l. – Amaro, UD, Italy), were placed in the posterior maxilla of 15 patients. Patients received one of each type of SEI placed on controlateral side. RESULTS: The proliferation rate studied by the MTT assay showed that during the incubation time, starting at 24 h, an increased proliferation rate was evident in Test B respect to Test A. After 2 months of unloaded healing BIC percent was significantly higher in oxidized implants. BIC percent mean values for the Osseogrip surface was 36,133 +/-4,888 ER and 53,533 +/- 5,180 ER for the Evo surface(P = 0,028). CONCLUSION: These results seem to confirm that implant surface topography entails mechanical restrictions to the spread and locomotion of the cells involved in bone healing.


Assuntos
Implantes Dentários , Adulto , Proliferação de Células , Células Cultivadas , Método Duplo-Cego , Humanos , Osteoblastos/fisiologia , Oxirredução , Cicatrização
15.
J Periodontol ; 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23106506

RESUMO

Background: The aim of the present randomized controlled clinical trial was to assess the bucco-lingual bone changes of implants immediately placed in fresh extraction sockets in association or not with porcine bone. Methods: Forty patients were included in the present study, and were randomly assigned to the control (n = 20) and test (n = 20) groups. Each patient received a single implant placed into an immediate extraction site of a molar or a first upper premolar with a flapless approach. In the control sites no grafting material was placed, while in the tests a deantigenated collagenated bone substitute of porcine origin was used to fill the gaps between the implant and the extraction socket. The bucco-lingual bone width was measured at different time points: at the time of surgery (T0), at 90 days (T1), at 110 days (T2) and after 6 months of masticatory function (T3). The values were statistically analyzed between and within the treatment groups (p>0.05). Results: All the implants were osseointegrated. Four control implants were excluded from the analysis due to the exposure of the coronal portion of the fixture. At T1, T2 and T3, statistically significant differences were found by comparing the mean width of the bucco-lingual bone between control and test groups. The mean values decreased during the observation period in both groups; statistically significant differences within controls were detected at T1, T2 and T3, and at T2 and T3 within tests. Conclusions: The outcomes of present study suggested that porcine bone enabled to avoid bucco-lingual crestal bone changes in implants immediately placed in fresh extraction sockets.

16.
Implant Dent ; 20(2): 131-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21448022

RESUMO

PURPOSE: The aim of this study was to assess the fractal dimension (Df) of disks with 3 different surface topographies. MATERIALS AND METHODS: Thirty disk-shaped samples (10 × 2 mm) with 3 different surface topographies (Dental Tech, Misinto, Italy) were analyzed by scanning electron microscopy: group A, machined surface; group B, titanium plasma-spray surface; group C, acid-etched and sandblasted surface (Blasted Wrinkled Surface). RESULTS: The amplitude roughness parameter (Sa) of the machined surfaces was 0.6 µm, while the developed surface area ratio (Sdr) was 14%; for the titanium plasma-spray surfaces, the values were, respectively, 5.3 µm and 97%, and for the Blasted Wrinkled Surfaces, 1.5 µm and 63%. Images at 1.000, 20.000, and 50.000 magnifications were processed for quantitative analysis of Df using the box-counting method. At 1.000×, Df for group A, B, and C was 1.86, 1.80, and 1.81, respectively; at 20.000×, Df for group A, B, and C was 1.85, 1.71, 1.58, respectively; and at 50.000×, Df was 1.83, 1.61, and 1.51 for A, B, and C groups. Statistically significant differences were found for Df values. CONCLUSIONS: Df provides not only an index of roughness size values but also a measure of roughness spatial organization; therefore, it could be a promising method to differentiate between rough surfaces capable of supporting osseointegration.


Assuntos
Implantes Dentários , Materiais Dentários/química , Fractais , Condicionamento Ácido do Dente/métodos , Óxido de Alumínio/química , Materiais Revestidos Biocompatíveis/química , Corrosão Dentária/métodos , Humanos , Ácido Fluorídrico/química , Processamento de Imagem Assistida por Computador/métodos , Microscopia Eletrônica de Varredura , Ácido Nítrico/química , Gases em Plasma/química , Propriedades de Superfície , Titânio/química
17.
Minerva Stomatol ; 60(3): 133-8, 2011 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-21270739

RESUMO

This case report presents a solid variant of keratocystic odontogenic tumour (KCOT), a benign uni- or multicystic intraosseous tumour of odontogenic origin, with a characteristic lining of parakeratinized stratified squamous epithelium and potential inflammatory infiltrate. A 52-year old female patient discovered occasionally, in an orthopantomography done for other reasons, the presence of a radiolucent lesion. A 2-3 cm wide lesion with well-demarcated margins was present in the premolar region of the left hemimandible. Under local anesthesia a biopsy was done and the diagnosis of odontogenic keratocyst was confirmed by histopathological examination. Under general anesthesia, the lesion was easily shelled-out and completely enucleated. The lesion had not recurred after a 6 years follow-up. The occurrence of a solid variant of KCOT could strengthen the hypothesis of a neoplastic rather than cystic nature of this lesion.


Assuntos
Neoplasias Mandibulares/patologia , Cistos Odontogênicos/patologia , Tumores Odontogênicos/patologia , Feminino , Humanos , Pessoa de Meia-Idade
18.
J Biol Regul Homeost Agents ; 24(3): 359-66, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20846484

RESUMO

Cigarette smoke contains oxidants such as oxygen-free radicals and volatile aldehydes, which are probably the major causes of damage to biomolecules exposed to cigarette smoke. However, saliva has an antioxidant defense system able to counter toxic activities of radical species that is formed by antioxidant enzymes, including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). The purpose of this study is to verify the possible effects of cigarette smoke on SOD and GSH-Px. Forty-four patients (25 males and 19 females) were enrolled in this study. The participants were 20 smokers (12 males and 8 females) and 24 non-smokers (13 males and 11 females). Furthermore, 10 subjects of the control group were ex-smokers (9 males and 1 female). Their mean age plus or minus standard deviation (SD) was 58.8 plus or minus 15.9 years for the case group and 73.8 plus or minus 10.6 years for the control group. All patients were underwent a careful anamnestic investigation and examination of the oral cavity. After rinsing the mouth with water, each subject put 3 cc of non-stimulated saliva inside a test tube. The saliva was centrifuged and oral peroxidase and superoxide dismutase activity was measured according to a specific assay. Statistical analysis was performed to evaluate differences between the groups and significant differences were observed for p less than 0.05. A significant decrease of GSH-Px activity was detected in the smoking group (p less than 0.05), while the SOD activity was similar in the control and case groups. According to the sex, a significant decrease of GSH-Px activity was noted in males of the smoker group (p less than 0.05), while in the sample of females no significant difference of the enzymatic activity was found. Moreover, among ex-smokers, there was a significant difference in the values of GSH-Px between those who had not smoked for less than ten years and those who had not smoked for more than ten years. Cigarette smoke may alter the detoxification of hydrogen peroxide through a decrease of GSH-Px activity. The overproduction of H2O2 may lead to an oxidative stress that is involved in a large number of diseases, including precancerous and neoplastic lesions of the oral cavity. The effects of cigarette smoke on salivary antioxidant enzymes decrease after withdrawal from smoking and the benefits become more evident with the passage of time.


Assuntos
Glutationa Peroxidase/metabolismo , Saliva/enzimologia , Fumar/metabolismo , Superóxido Dismutase/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Br J Cancer ; 103(3): 382-90, 2010 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-20606680

RESUMO

BACKGROUND: The aim of this study was to elucidate the prognostic impact of putative cancer stem cell markers CD133, CD166, CD44s, EpCAM, and aldehyde dehydrogenase-1 (ALDH1) in colorectal cancer. METHODS: A tissue microarray of 1420 primary colorectal cancers and 57 normal mucosa samples was immunostained for CD133, CD166, CD44s, EpCAM, and ALDH1 in addition to 101 corresponding whole tissue sections. Invasive potential of three colorectal cancer cell lines was tested. RESULTS: Differences between normal tissue and cancer were observed for all markers (P<0.001). Loss of membranous CD166 and CD44s were linked to higher pT (P=0.002, P=0.014), pN (P=0.004, P=0.002), an infiltrating growth pattern (P<0.001, P=0.002), and worse survival (P=0.015, P=0.019) in univariate analysis only. Loss of membranous EpCAM expression was also linked to higher pN (P=0.023) and infiltrating growth pattern (P=0.005). The CD44s, CD166, and EpCAM expression were lost towards the invasive front. The CD44-/CD166- cells from three colorectal cancer cell lines exhibited significantly higher invasive potential in vitro than their positive counterparts. CONCLUSIONS: Loss, rather than overexpression, of membranous CD44s, CD166, and EpCAM is linked to tumour progression. This supports the notion that the membranous evaluation of these proteins assessed by immunohistochemistry may be representative of their cell adhesion rather than their intra-cellular functions.


Assuntos
Aldeído Desidrogenase/genética , Antígenos CD/genética , Antígenos de Neoplasias/genética , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular/genética , Neoplasias Colorretais/genética , Proteínas Fetais/genética , Glicoproteínas/genética , Receptores de Hialuronatos/genética , Isoenzimas/genética , Peptídeos/genética , Antígeno AC133 , Adulto , Idoso , Idoso de 80 Anos ou mais , Família Aldeído Desidrogenase 1 , Divisão Celular , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Molécula de Adesão da Célula Epitelial , Feminino , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Perda de Heterozigosidade/genética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Valores de Referência , Retinal Desidrogenase , Células-Tronco/patologia , Taxa de Sobrevida
20.
Br J Cancer ; 101(8): 1382-92, 2009 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19755986

RESUMO

BACKGROUND: The tumour-host interaction at the invasive front of colorectal cancer, including the epithelial-mesenchymal transition and its hallmark 'tumour budding', is an important area of investigation in terms of prognosis. The aim of this study was to determine the prognostic impact of a 'pro-/anti-tumour' approach defined by an established 'pro-tumour' (tumour budding) and host-related 'anti-tumour' factor of the adaptive immunological microenvironment (CD8+ lymphocytes). METHODS: Double immunostaining for CK22/CD8 on whole tissue sections (n=279; Cohort 1) and immunohistochemistry for CD8+ using tissue microarrays (n=191; Cohort 2) was carried out. Tumour buds, CD8+ and CD8+ T-lymphocytes : tumour buds indices were evaluated per high-power field. RESULTS: In Cohort 1, a low-CD8+/ buds index was associated with lymph node metastasis (P<0.001), vascular invasion (P=0.009), worse survival in univariate (P<0.001) and multivariable (P<0.001) analysis, and furthermore in lymph node-negative patients (P=0.002). In Cohort 2, the CD8+/ buds index was associated with T stage (P<0.001), N stage (P=0.041), vascular invasion (P=0.005) and survival in patients with TNM stage II (P=0.019), stage III (P=0.004), and adjuvantly untreated (P=0.009) and treated patients (P<0.001). CONCLUSION: The CD8+ lymphocyte : tumour-budding index is an independent prognostic factor in colorectal cancer and a promising approach for a future prognostic score for patients with this disease.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Humanos , Instabilidade de Microssatélites , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Análise Serial de Tecidos , Proteínas ras/genética
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