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1.
Braz J Med Biol Res ; 55: e12076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36000612

RESUMO

Glioblastoma is the most prevalent and malignant brain tumor identified in adults. Surgical resection followed by radiotherapy and chemotherapy, mainly with temozolomide (TMZ), is the chosen treatment for this type of tumor. However, the average survival of patients is around 15 months. Novel approaches to glioblastoma treatment are greatly needed. Here, we aimed to investigate the anti-glioblastoma effect of the combination of matteucinol (Mat) (dihydroxyflavanone derived from Miconia chamissois Naudin) with the chemotherapeutic TMZ in vitro using tumor (U-251MG) and normal astrocyte (NHA) cell lines and in vivo using the chick embryo chorioallantoic membrane (CAM) assay. The combination was cytotoxic and selective for tumor cells (28 µg/mL Mat and 9.71 µg/mL TMZ). Additionally, the combination did not alter cell adhesion but caused morphological changes characteristic of apoptosis in vitro. Notably, the combination was also able to reduce tumor growth in the chick embryo model (CAM assay). The docking results showed that Mat was the best ligand to the cell death membrane receptor TNFR1 and to TNFR1/TMZ complex, suggesting that these two molecules may be working together increasing their potential. In conclusion, Mat-TMZ can be a good candidate for pharmacokinetic studies in view of clinical use for the treatment of glioblastoma.


Assuntos
Glioblastoma , Receptores Tipo I de Fatores de Necrose Tumoral , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Embrião de Galinha , Cromonas , Biologia Computacional , Glioblastoma/tratamento farmacológico , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico
2.
Braz. j. med. biol. res ; 55: e12076, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394123

RESUMO

Glioblastoma is the most prevalent and malignant brain tumor identified in adults. Surgical resection followed by radiotherapy and chemotherapy, mainly with temozolomide (TMZ), is the chosen treatment for this type of tumor. However, the average survival of patients is around 15 months. Novel approaches to glioblastoma treatment are greatly needed. Here, we aimed to investigate the anti-glioblastoma effect of the combination of matteucinol (Mat) (dihydroxyflavanone derived from Miconia chamissois Naudin) with the chemotherapeutic TMZ in vitro using tumor (U-251MG) and normal astrocyte (NHA) cell lines and in vivo using the chick embryo chorioallantoic membrane (CAM) assay. The combination was cytotoxic and selective for tumor cells (28 μg/mL Mat and 9.71 μg/mL TMZ). Additionally, the combination did not alter cell adhesion but caused morphological changes characteristic of apoptosis in vitro. Notably, the combination was also able to reduce tumor growth in the chick embryo model (CAM assay). The docking results showed that Mat was the best ligand to the cell death membrane receptor TNFR1 and to TNFR1/TMZ complex, suggesting that these two molecules may be working together increasing their potential. In conclusion, Mat-TMZ can be a good candidate for pharmacokinetic studies in view of clinical use for the treatment of glioblastoma.

3.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 868-876, Jul.-Aug. 2021. graf, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285271

RESUMO

The melanomacrophage centers (MMCs) in the liver of fish are indicators of environmental conditions, as they are involved in xenobiotic biotransformation. The objective of this study was to evaluate the number of MMC in the liver of juveniles and adults of Sciades herzbergii from areas with different levels of contamination. The fish were caught at three points (reference - A1, potentially impacted - A2 and contaminated - A3), in São José bay (Maranhão, Brazil), in four samples. The livers were subjected to the standard histological procedure and 5µm sections were stained with hematoxylin-eosin. In livers of A2 adult individuals (260.50±161.50 MMCs / mm²) they presented a greater number of MMCs when compared to A3 adults (60.00 ± 30.10 MMCs / mm²). Juveniles showed considerable values in A1 (100.00 ± 0.00 MMCs/mm²) and A2 (95.33 ± 33.00 MMCs / mm²) compared to juveniles in A3 (49.00±0.00 MMCs/mm²). These high values are unexpected for young people. The average number of MMC correlated with the rainy season in the region. The use of hepatic MMCs as a biomarker of exposure to pollutants, in particular substances from fisheries systems, such as ammonia and nitrite, proved to be adequate to differentiate areas with different levels of impacts.(AU)


Os centros melanomacrófagos (MMCs) no fígado de peixes são indicadores das condições ambientais, pois estão envolvidos na biotransformação xenobiótica. O objetivo deste estudo foi avaliar o número de MMC no fígado de juvenis e adultos de Sciades herzbergii de áreas com diferentes níveis de contaminação. Os peixes foram capturados em três pontos (referência - A1; potencialmente impactado - A2; e contaminado - A3), na baía de São José (Maranhão, Brasil), em quatro amostras. Os fígados foram submetidos ao procedimento histológico padrão e cortes de 5µm foram corados com hematoxilina-eosina. Em fígados de indivíduos adultos A2 (260,50±161,50 MMCs/mm²), eles apresentaram maior número de MMCs quando comparados aos adultos A3 (60,00±30,10 MMCs/mm²). Os juvenis apresentaram valores elevados em A1 (100,00 ± 0,00 MMCs/mm²) e A2 (95,33±33,00 MMCs/mm²) quando comparados aos juvenis em A3 (49,00±0,00 MMCs/mm²). Esses altos valores são inesperados para os jovens. O número médio de MMC correlacionou-se com a época chuvosa na região. A utilização de MMCs hepáticos como biomarcador de exposição a poluentes, em particular substâncias provenientes de sistemas pesqueiros, como amônia e nitrito, mostrou-se adequada para diferenciar áreas com diferentes níveis de impactos.(AU)


Assuntos
Animais , Peixes-Gato , Biomarcadores Ambientais , Monitoramento Biológico/métodos , Células de Kupffer , Células de Kupffer/citologia , Poluição Ambiental/análise
4.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1959-1964, Sept.-Oct. 2020. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131525

RESUMO

This study aimed to estimate genetic parameters for simulated data of body weight (BW), abdominal width (AW), abdominal length (AL), and oviposition. Simulation was performed based on real data collected at apiaries in the region of Campo das Vertentes, Minas Gerais, Brazil. Genetic evaluations were performed using single- and two-trait models and (co)variance components were estimated by the restricted maximum likelihood method. The heritability for BW, AW, AL and oviposition were 0.54, 0.47, 0.31 and 0.66, respectively. Positive genetic correlations of high magnitude were obtained between BW and AW (0.80), BW and oviposition (0.69), AW and oviposition (0.82), and AL and oviposition (0.96). The genetic correlations between BW and AL (0.11) and between AW and AL (0.26) were considered moderate and low. In contrast, the phenotypic correlations were positive and high between BW and AW (0.97), BW and AL (0.96), and AW and AL (0.98). Phenotypic correlations of low magnitude and close to zero were obtained for oviposition with AL (0.02), AW (-0.02), and BW (-0.03). New studies involving these characteristics should be conducted on populations with biological data in order to evaluate the impact of selection on traits of economic interest.(AU)


Objetivou-se estimar parâmetros genéticos para dados simulados de peso corporal (PC), largura abdominal (LA), comprimento abdominal (CA) e oviposição (OV). A simulação foi conduzida com base em dados reais, coletados em apiários da região do Campo das Vertentes, Minas Gerais. As estimativas das análises genéticas foram realizadas por modelos uni e bicaracterísticos, sendo os componentes de (co) variância estimados pelo método da máxima verossimilhança restrita. As herdabilidades para PC, LA, CA e OV foram de 0,54, 0,47, 0,31 e 0,66 respectivamente. As correlações genéticas foram positivas e de alta magnitude para PC e LA (0,80), PC e OV (0,69), LA e OV (0,82) e CA e OV (0,96). Para PC e CA (0,11) e LA e CA (0,26), as correlações genéticas foram moderadas e de baixa magnitude. As correlações fenotípicas foram positivas e de alta magnitude para PC e LA (0,97), PC e CA (0,96) e LA e CA (0,98). Para OV e CA (0,02), OV e LA (-0,02) e OV e PC (-0,03), foram encontradas correlações fenotípicas de magnitude baixa e próximas de zero. Novos estudos devem ser realizados em populações com dados biológicos, a fim de se observar o impacto da seleção em características de interesse econômico.(AU)


Assuntos
Animais , Oviposição/genética , Abelhas/genética , Peso Corporal/genética , Pesos e Medidas Corporais/classificação , Hereditariedade , Correlação de Dados
5.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1413-1423, July-Aug. 2020. tab, graf, ilus, mapas
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131511

RESUMO

Objetivou-se neste estudo analisar biomarcadores histológicos e bioquímicos em brânquias de U. cordatus indicativos de impactos na Baía de São Marcos. Caranguejos foram coletados em quatro áreas na Baía de São Marcos: A1= Ilha dos Caranguejos (com baixo impacto); A2= Coqueiro, A3= Porto Grande, A4= Cajueiro (áreas potencialmente impactadas). Mediram-se os dados biométricos de cada exemplar de caranguejo. Amostras de brânquias foram submetidas à técnica histológica padrão e homogeneizadas em tampão fosfato, e o sobrenadante foi utilizado para análise das enzimas glutationa-S-transferase (GST) e catalase (CAT). A biometria indicou que os caranguejos de A1 são significativamente (P<0,05) maiores e mais pesados do que os caranguejos das áreas A2, A3 e A4. As alterações branquiais (rompimento das células pilastras, deformação do canal marginal, deslocamento da cutícula e necrose) foram significativamente (P˂0,05) mais frequentes em caranguejos de A2, A3 e A4 do que nos caranguejos de A1. As atividades enzimáticas da GST e CAT nos caranguejos apresentaram diferença significativa (P<0,05) entre as áreas de coletas, com padrão similar ao observado para as alterações branquiais. Os biomarcadores analisados mostraram que os caranguejos estão sob diferentes níveis de impactos (A4>A3>A2>A1) ao longo da Baía de São Marcos.(AU)


The objective of this study was to analyze histological and biochemical biomarkers in U. cordatus gills indicative of impacts in São Marcos Bay. Crabs were collected from four areas in São Marcos Bay: A1=Ilha dos Caranguejos (with low impact); A2=Coqueiro, A3=Porto Grande, A4=Cajueiro (potentially impacted areas). The biometric data of each specimen was measured. Gill samples were submitted to standard histological technique and homogenized in phosphate buffer, and the supernatant was used for analysis of glutathione S-transferase (GST) and catalase (CAT) enzyme activity. Biometric data indicated that crabs found in A1 are significantly (P<0.05) larger and heavier than crabs found in A2, A3 and A4 areas. Gill alterations (rupture of pilaster cells, Dilation of the marginal channel, Cuticle Rupture and necrosis) were significantly (P˂0.05) more frequent in the crabs in A2, A3 and A4 than crabs in A1. The enzymatic activities of GST and CAT showed significant difference (P<0.05) between the sampling areas, similar to that observed for gill alterations. The biomarkers analyzed showed that the crabs are under different impact levels (A4> A3> A2> A1) along the São Marcos Bay.(AU)


Assuntos
Animais , Biomarcadores/análise , Xenobióticos , Catalase , Braquiúros/anatomia & histologia , Brânquias/anatomia & histologia , Glutationa Transferase , Brasil , Meio Ambiente
6.
Biomed Phys Eng Express ; 6(2): 025006, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33438632

RESUMO

PURPOSE: To develop the enabling algorithmic techniques which allow forward-peaked adaptive angular meshing to be compatible with angular advection of magnetic fields within a deterministic Grid Based Boltzmann Solver (GBBS) for MRI-guided radiotherapy, and establish appropriate energy adaptive meshing schemes which minimize total numerical degrees of freedom while preserving high dosimetric accuracy for parallel and perpendicular magnetic fields. METHODS: A framework to independently adapt angular mesh resolution and basis function refinement of forward and backscattering hemispheres is developed, uniquely accommodating angular advection introduced by magnetic fields. Upwind stabilization techniques to accurately transfer fluence between hemispheres having different discretization are established. To facilitate oblique beam and magnetic field orientations, cardinal forward-peaked mesh orientations were devised to balance requirements for acyclic space-angle sweep ordering, while ensuring the beam predominantly overlaps the forward hemisphere. Energy-dependent fluence anisotropy is investigated, leading to adaptive angular meshing schemes for parallel and perpendicular magnetic fields. Calculated dose distributions were validated against GEANT4 Monte Carlo calculations on slab geometry and anthropomorphic phantoms. RESULTS: Forward-peaked and isotropic energy adaptive angular meshing schemes were developed for parallel and perpendicular magnetic fields respectively, which reduce the number of elements solved by 52.8% and 47.7% respectively compared to static discretization using 32 quadratic elements while retaining over 97% of points passing the gamma 1%/1 mm criterion against Monte Carlo. CONCLUSIONS: Techniques to preserve angular upwind-stabilization between hemispheres of a forward-peaked mesh and establish an acyclic directed space-angle sweep graph enabled energy-adaptive meshing schemes to be developed while accurately solving for magnetic fields. This substantially reduced the numerical degrees of freedom while retaining excellent dosimetric agreement with Monte Carlo. These algorithmic underpinnings contribute towards a fast deterministic GBBS for MRI-guided radiotherapy.


Assuntos
Algoritmos , Campos Magnéticos , Imageamento por Ressonância Magnética/métodos , Método de Monte Carlo , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Estudos de Viabilidade , Humanos , Radiometria , Dosagem Radioterapêutica
7.
Int J Oral Maxillofac Surg ; 49(9): 1220-1231, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29685387

RESUMO

No consensus has been reached regarding the influence of the flapless and open-flap surgical techniques on the placement of dental implants. This systematic review compared the effects of flapless implant placement and implant placement with elevation of the mucoperiosteal flap in terms of marginal bone loss, implant survival rate and complications rates. This review followed PRISMA guidelines and was registered in PROSPERO with the registration number CRD42017071475. Two independent reviewers performed a comprehensive search of the PubMed/MEDLINE, Scopus, and Cochrane Library databases for studies published until December 2017. The search identified 559 references. After a detailed review, 24 studies were assessed for eligibility. A total of 1025 patients who had received a total of 1873 dental implants were included. There were no significant differences between the flapless and open-flap surgical techniques in terms of implant survival rates (P=0.34; risk ratio (RR): 1.36; confidence interval (CI): 0.72-2.56), marginal bone loss (P=0.23; MD: -0.20; CI: -0.52-0.13), or complication rates (P=0.67; RR: 1.10; CI: 0.70-1.73). The current meta-analysis showed that the implant survival rate, marginal bone levels, and complications of flapless surgery were similar to those of open-flap surgery over a mean follow-up period of 21.62 months.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Humanos , Retalhos Cirúrgicos
8.
Phys Med Biol ; 64(18): 185012, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31344697

RESUMO

Accurate and efficient patient dose calculations are essential for treatment planning in magnetic resonance imaging guided radiotherapy (MRIgRT). Achieving reasonable performance for a space-angle discontinuous finite element method (DFEM) grid based Boltzmann solver (GBBS) with magnetic fields for clinical MRIgRT applications largely depends on how the transport sweep is orchestrated. Compared to classical Discrete Ordinates, DFEM in angle introduces increased angular degrees of freedom and eliminates ray-effect artifacts. However, the inclusion of magnetic fields introduces additional serial dependencies such that parallelization of the space-angle transport sweeps becomes more challenging. Novel techniques for the transport sweep and right-hand source assembly are developed, predicated on limiting the number of bulk material densities modeled in the transport sweep scatter calculations. Specifically, k-means clustering is used to assign sub-intervals of mass-density for each spatial element to execute the scatter-dose calculations using batched multiplication by pre-inverted transport sweep matrices. This is shown to be two orders of magnitude more efficient than solving each elemental system individually at runtime. Even with discrete material densities used in the transport sweep scatter calculations, accuracy is maintained by optimizing the material density assignments using k-means clustering, and by performing the primary photon fluence calculations (ray-tracing) using the underlying continuous density of the computed tomography (CT) image. In the presence of 0.5 T parallel and 1.5 T perpendicular magnetic fields, this approach demonstrates high levels of accuracy with gamma 1%/1 mm passing rates exceeding 94% across a range of anatomical sites compared to GEANT4 Monte Carlo dose calculations which used continuous densities. This deterministic GBBS approach maintains unconditional stability, produces no ray-effect artifacts, and has the benefit of no statistical uncertainty. Runtime on a non-parallelized Matlab implementation averaged 10 min per beam averaging 80 000 spatial elements, paving way for future development based on this algorithmically efficient paradigm.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Hepáticas/radioterapia , Neoplasias Pulmonares/radioterapia , Imageamento por Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Algoritmos , Artefatos , Neoplasias Encefálicas/diagnóstico por imagem , Análise por Conglomerados , Análise de Elementos Finitos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Método de Monte Carlo , Fótons , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X
9.
Med Phys ; 46(2): 822-838, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30488968

RESUMO

PURPOSE: Real-time magnetic resonance (MR) guidance is of interest to various groups globally because the superior soft tissue contrast MR images offer over other x-ray-based imaging modalities. Because of the precision required in proton therapy, proton therapy treatments rely heavily on image guidance. Integrating a magnetic resonance imaging (MRI) into a proton therapy treatment is a challenge. The charged particles (protons) used in proton therapy experience magnetic forces when travelling through the MRI magnetic fields. Given that it is desired that proton beams can be delivered with submillimeter accuracy, it is important that all potential sources of beam displacement are well modeled and understood. This study investigated the behavior of monoenergetic proton beams in the presence of a simulated set of realistic three-dimensional (3D) vector magnetic gradient fields required for spatial localization during imaging. This deflecting source has not been previously investigated. METHODS: Three-dimensional magnetic vector fields from a superconducting 0.5 T open bore MRI magnet model (previously developed in-house) and 3D magnetic fields from an in-house gradient coil model were applied to two types of computer simulations. In all simulations, monoenergetic proton pencil beams (from 80 to 250 MeV) were used. The initial directions of proton beams were varied. In all simulations, the orientation of the B0 field coincided with the positive z-axis in the simulation geometry. The first type of simulation is based on an analytic magnetic force equation (analytic simulations) while the second type is a full Monte Carlo (MC) simulation. The analytic simulations were limited to propagating the proton beams in vacuum but could be rapidly calculated in a desktop computer while the MC simulations were calculated in a cluster computer. The proton beam locations and dose profiles at the central plane (z = 0 cm) with or without magnetic fields were extracted and used to quantify the effect of the presence of the different magnetic fields on the proton beam. RESULTS: The analytic simulations agree with MC results within 0.025 mm, thus acting as the verification of MC calculations. The presence of the B0 field caused the beam to follow a helical trajectory which resulted in angular offsets of 4.9o , 3.6o , and 2.8o for the 80, 150, and 250 MeV, respectively. Magnetic field deflections caused by a rapid MRI sequence (bSSFP, with maximum gradient strength of 40 mT/m) show a pattern of distortion which remained spatially invariant in the MR's field of view. For the 80 MeV beam, this pattern shows a maximum ranged in the y direction of 1.5 mm. The presence of the B0 field during the bSSFP simulations adds the same beam rotation to the observed during the B0 only simulations. CONCLUSION: This investigation reveals that time-varying gradient magnetic fields required for image generation can cause a small spread in the proton beams used in the study which are independent of the effects arising from the B0 field. Further, studies where clinical beam kernels were convolved with this spread show that these magnetic fields are expected to have an insignificant impact on the beam's entrance dose.


Assuntos
Campos Magnéticos , Imageamento por Ressonância Magnética , Terapia com Prótons/métodos , Rotação , Fatores de Tempo
11.
Br J Oral Maxillofac Surg ; 56(4): 256-266, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29655661

RESUMO

Patients who have maxillectomy can be rehabilitated with reconstructive surgery or obturator prostheses with or without osseointegratable implants. To identify studies on possible treatments in this group, we systematically searched the Scopus, Embase, PubMed/Medline, and Cochrane databases to collect data on patients' characteristics, radiotherapy, and results related to speech, swallowing, mastication or diet, chewing, aesthetics, and quality of life. Of the 1376 papers found, six were included, and one other was included after an additional search of references. A total of 252 patients were included, and of them, 86 had reconstructive surgery, 91 were treated with obturator prostheses, 39 had reconstructive surgery or obturator prostheses associated with implants, and 36 had reconstruction plus an obturator prosthesis. Data on radiotherapy were incomplete. There is a lack of consensus about the indication for rehabilitation, as the treatment must be based on the individual characteristics of each patient.


Assuntos
Reconstrução Mandibular/reabilitação , Maxila/cirurgia , Humanos , Prótese Maxilofacial , Obturadores Palatinos
12.
Int J Oral Maxillofac Surg ; 47(9): 1166-1177, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29459128

RESUMO

The aim of this meta-analysis was to verify the clinical viability of single implant-retained mandibular overdentures (SIMO). An electronic search of the PubMed and Cochrane databases was performed (end date July 2017); this was supplemented by a manual search of the literature. Only prospective clinical trials and randomized controlled trials (RCTs) that evaluated SIMO with a minimum follow-up of 12 months were included. The meta-analysis was based on the Mantel-Haenszel method. Dental implant and prosthetic failure were the dichotomous outcome measures; these were evaluated through the risk ratio (RR) and odds ratio (OR), with corresponding 95% confidence intervals (CI). Of 499 articles identified, nine fulfilled the inclusion criteria. A total of 205 implants were placed in patients with a mean age of 64.1 years; the cumulative survival rate was 96.6% over a mean follow-up period of 37.3 months. The procedure used (SIMO vs. two implant-retained mandibular overdenture) did not affect dental implant failure (P=0.45) or prosthetic failure (P=0.65): RR 1.06 (95% CI 0.91-1.23) and RR 0.88 (95% CI 0.51-1.51), respectively; OR 2.56 (95% CI 0.27-24.39; P=0.41) and OR 0.44 (95% CI 0.15-1.26; P=0.13), respectively. Within the limitations of this systematic review and meta-analysis, SIMO with a complete denture as the opposing arch may be considered an alternative treatment for completely edentulous patients. However, this study also confirmed the need for more RCTs on this topic.


Assuntos
Prótese Dentária Fixada por Implante , Revestimento de Dentadura , Mandíbula , Implantes Dentários para Um Único Dente , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Humanos
13.
Int J Oral Maxillofac Surg ; 46(9): 1162-1177, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28478869

RESUMO

The aim of this systematic review and meta-analysis was to compare the survival rate of the implants and the peri-implant tissue changes associated with implants inserted in fresh extraction sockets and those inserted in healed sockets. This review has been registered at PROSPERO under the number CRD42016043309. A systematic search was conducted by two reviewers independently in the databases PubMed/MEDLINE, Embase, and the Cochrane Library using different search terms; articles published until November 2016 were searched for. The searches identified 30 eligible studies. A total of 3,049 implants were installed in a total of 1,435 patients with a mean age of 46.68 years and a minimum of 6 months of follow-up. The survival rate of delayed implants (98.38%) was significantly greater than immediate implants (95.21%) (p=.001). For the marginal bone loss (p=.32), implant stability quotients values (p=.44), and pocket probing depth (p=.94) there was no significant difference between the analysed groups. The immediate implants placed in fresh sockets should be performed with caution because of the significantly lower survival rates than delayed implants inserted in healed sockets.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários para Um Único Dente , Alvéolo Dental/cirurgia , Falha de Restauração Dentária , Humanos , Carga Imediata em Implante Dentário/métodos , Extração Dentária
14.
Int J Oral Maxillofac Surg ; 46(11): 1437-1445, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28521965

RESUMO

A better understanding of factors that can lead to papilla formation or recession, such as the type of site where the implant was placed, is of fundamental importance to the aesthetic success of the rehabilitation. The aim of this study was to perform a systematic review of the literature regarding the formation or recession of papilla adjacent to implants placed in fresh, healing or healed sites. The protocol for this study was registered in the PROSPERO database (registration number CRD 42016033784). An electronic search was performed by two independent reviewers who applied the inclusion and exclusion criteria on the PubMed/MEDLINE, Scopus, and Embase databases from January 2005 up to February 2016. The initial screening yielded 1,065 articles, from which 15 were selected for a systematic review after applying the inclusion and exclusion criteria. Nine studies compared fresh and healed sites, four studies compared healing and healed sites, one study compared fresh and healing sites, and one study analysed all three sites. The majority of studies identified by this systematic review showed no difference between groups after the longer follow-up period. The sites where the implants were placed did not have a long-term influence on papilla formation or recession.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Papila Dentária/fisiologia , Retração Gengival/fisiopatologia , Cicatrização/fisiologia , Estética Dentária , Humanos
15.
Int J Oral Maxillofac Surg ; 45(12): 1531-1537, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27374020

RESUMO

This systematic review aimed to investigate whether intra-articular injections of hyaluronic acid (HA) are better than other drugs used in temporomandibular joint arthrocentesis, for the improvement of temporomandibular disorder (TMD) symptoms. Two independent reviewers performed an electronic search of the MEDLINE and Web of Science databases for relevant studies published in English up to March 2016. The key words used included a combination of 'hyaluronic acid', 'viscosupplementation', 'intra-articular injections', 'corticosteroids', or 'non steroidal anti inflammatory agents' with 'temporomandibular disorder'. Selected studies were randomized clinical trials and prospective or retrospective studies that primarily investigated the application of HA injections compared to other intra-articular medications for the treatment of TMD. The initial screening yielded 523 articles. After evaluation of the titles and abstracts, eight were selected. Full texts of these articles were accessed and all fulfilled the inclusion criteria. Intra-articular injections of HA are beneficial in improving the pain and/or functional symptoms of TMDs. However, other drug therapies, such as corticosteroid and non-steroidal anti-inflammatory drug injections, can be used with satisfactory results. Well-designed clinical studies are necessary to identify an adequate protocol, the number of sessions needed, and the appropriate molecular weight of HA for use.


Assuntos
Ácido Hialurônico/administração & dosagem , Transtornos da Articulação Temporomandibular/tratamento farmacológico , Viscossuplementos/administração & dosagem , Humanos , Injeções Intra-Articulares , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
16.
Int J Oral Maxillofac Surg ; 45(4): 517-25, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26775635

RESUMO

This systematic review evaluated the effect on bone formation and implant survival of combining platelet-rich plasma (PRP) with bone grafts in maxillary augmentation. A comprehensive review of articles listed in the PubMed/MEDLINE, Embase, and Cochrane Library databases covering the period January 2000 to January 2015 was performed. The meta-analysis was based on bone formation for which the mean difference (MD, in millimetres) was calculated. Implant survival was assessed as a dichotomous outcome and evaluated using the risk ratio (RR) with 95% confidence interval (CI). The search identified 3303 references. After inclusion and exclusion criteria were applied, 17 studies were selected for qualitative analysis and 13 for quantitative analysis. A total of 369 patients (mean age 51.67 years) and 621 maxillary sinus augmentations were evaluated. After the data analysis, additional analyses were performed of the implant stability quotient, marginal bone loss, and alveolar bone height measured by MD. The results showed no significant difference in implant stability (P=0.32, MD 1.00, 95% CI -0.98 to 2.98), marginal bone loss (P=0.31, MD 0.06, 95% CI -0.05 to 0.16), alveolar bone height (P=0.10, MD -0.72, 95% CI -1.59 to 0.14), implant survival (P=0.22, RR 1.95, 95% CI 0.67-5.69), or bone formation (P=0.81, MD -0.63, 95% CI -5.91 to 4.65). In conclusion, the meta-analysis indicates no influence of PRP with bone graft on bone formation and implant survival in maxillary sinus augmentation.


Assuntos
Transplante Ósseo/métodos , Plasma Rico em Plaquetas , Levantamento do Assoalho do Seio Maxilar/métodos , Sobrevivência de Enxerto , Humanos , Osteogênese
17.
Int J Oral Maxillofac Surg ; 44(1): 127-31, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25457831

RESUMO

This study examined the electrical activity of the superior (SO) and inferior (IO) orbicularis oculi muscles before and after installing ocular prostheses in patients who had undergone unilateral enucleation. Twelve volunteers requiring prostheses were selected. Their electrical activity was monitored at rest and during normal opening and closing of the eyelids, rapid opening and closing of the eyelids, and squeezing. Data were recorded before and 7, 30, and 60 days after the ocular prosthesis was installed. Two-way analysis of variance was performed to verify whether there were any significant differences between the muscles and periods, and means were compared by Tukey-Kramer honestly significant difference (HSD) tests (P < 0.05). Results from the initial period differed significantly from those after prosthesis installation in all clinical situations. The SO had significantly higher electrical activity levels than the IO in all clinical situations but squeezing. The authors observed the same values during the initial period for the condition of rest (SO 8.42/IO 5.93) and the highest values for the condition of squeezing after 60 days (SO 131.50/IO 117.12). Rehabilitative treatment promoted an increase in the electrical activity of the orbicularis oculi muscles, restoring part of the muscle tone and motor function to muscles of the affected area.


Assuntos
Movimentos Oculares/fisiologia , Olho Artificial , Pálpebras/inervação , Músculo Esquelético/inervação , Idoso , Eletromiografia , Enucleação Ocular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Int J Oral Maxillofac Surg ; 43(9): 1108-16, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24679842

RESUMO

Bone quality and quantity are important factors with regard to the survival rate of dental implants. The aim of this study was to conduct a systematic review of dental implants inserted in low-density bone and to determine the survival rate of dental implants with surface treatments over time. A systematic review of the literature was undertaken by two independent individuals; the Medline/PubMed database was searched for the period July 1975 to March 2013. Relevant reports on bone quality and osseointegration of dental implants were selected. The search retrieved 1018 references, and after inclusion and exclusion criteria were applied, 19 studies were selected for review. A total of 3937 patients, who had received a total of 12,465 dental implants, were analyzed. The survival rates of dental implants according to the bone density were: type I, 97.6%; type II, 96.2%; type III, 96.5%; and type IV, 88.8%. The survival rate of treated surface implants inserted in low-density bone was higher (97.1%) than that of machined surface implants (91.6%). Surface-treated dental implants inserted in low-density bone have a high survival rate and may be indicated for oral rehabilitation. However, more randomized studies are required to better evaluate this issue.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Retenção em Prótese Dentária , Densidade Óssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Humanos , Osseointegração , Propriedades de Superfície
19.
Arq. bras. med. vet. zootec ; 66(2): 593-601, Jan.-Apr. 2014. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-709302

RESUMO

Com o objetivo de analisar a intensidade das alterações histológicas em brânquias de Centropomus undecimalis para avaliar a qualidade da água do Parque Ecológico Laguna da Jansen, em São Luís, Estado do Maranhão, coletaram-se exemplares de peixes no período chuvoso de 2012 e amostras de água nos períodos seco de 2011 e chuvoso de 2012 para análises físico-química e bacteriológica. Os resultados mostraram que a maioria dos parâmetros físico-químicos e bacteriológicos estava de acordo com os valores estabelecidos pela Resolução do CONAMA nº 357 de 2005. As alterações histológicas observadas foram: elevação do epitélio lamelar; proliferação excessiva de células dos epitélios filamentar e lamelar causando fusão total ou parcial das lamelas; alteração da estrutura das lamelas; hiperplasia das células mucosas; ruptura do epitélio lamelar; espessamento descontrolado do tecido proliferativo filamentar e lamelar e aneurismas de vários tamanhos. Também foi observada a presença de parasito em alguns exemplares. O Índice de Alteração Histológica (IAH) por indivíduo variou de 2 a 114. O valor médio do IAH obtido foi de 40,3, demonstrando que as brânquias dos indivíduos amostrados da espécie C. undecimalis apresentaram alterações de moderadas para severas no tecido. As alterações histológicas encontradas indicam que esses indivíduos desenvolveram mecanismos de defesa contra a ação de estressores presentes na água da laguna e a um provável desequilíbrio parasito-hospedeiro-ambiente associado à baixa qualidade do ambiente...


Aiming to analyze the intensity of the histological changes in the gills of Centropomus undecimalis to assess the water quality at Ecological Park of the Laguna da Jansen, in São Luís, State of Maranhão, specimens of fish were collected during the rainy season of 2012 and water samples during the dry season in 2011 and rainy season in 2012 for physical-chemical and bacteriological analyses. The results showed that most of the physical-chemical and bacteriological parameters analyzed agreed with the values established by CONAMA Resolution nº 357 of 2005. The histological changes were elevation of the lamellar epithelium, excessive cell proliferation of the filamentum and lamellar epithelium causing total or partial melting of the lamellar; changing the structure of the lamellar, hyperplasia of mucous cells, disruption of the lamellar epithelium, uncontrolled proliferative tissue filamentum thickening and lamellar and aneurysms in various sizes. We noted the presence of parasites in some samples. The Index Histological Amendment (IAH) per individual ranged from 2 to 114. The mean IAH obtained was 40.3, demonstrating that the gills of the individuals of the C. undecimalis species showed moderate to severe changes in the tissue. The histological findings indicate that these individuals have developed defense mechanisms against the action of stressors present in the water of the Laguna da Jansen and a probable parasite-host-environment imbalance associated with the environment's low quality...


Assuntos
Animais , Técnicas Bacteriológicas , Bass/anatomia & histologia , Bass/fisiologia , Brânquias/fisiopatologia , Brânquias/microbiologia , Características Bacteriológicas da Água , Bass/imunologia , Coliformes
20.
Int J Oral Maxillofac Surg ; 43(6): 748-57, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24530034

RESUMO

The purpose of this systematic review was to evaluate clinical studies on the follow-up survival of implants inserted in the zygomatic bone for maxillary rehabilitation. A comprehensive search of studies published from 2000 to July 2012 and listed in the PubMed/MEDLINE, Embase, and Cochrane Library databases was performed in accordance with the PRISMA statement. Relevant studies were selected according to predetermined inclusion and exclusion criteria. The initial database search yielded 751 titles. After filtering, 313 abstracts were selected, culminating in 42 full text articles. Application of eligibility criteria led to the elimination of 17 articles. Hence 25 full-text articles were considered clinically relevant and were included. Calculations of the interval survival rates and cumulative survival rates of implants could be carried out on the data extracted from the final list of included studies for the different time intervals. These studies reported the insertion of a total of 1541 zygomatic implants and 33 implant failures. Failure generally occurred during the first year interval and was related to clinical complications, such as recurrent acute and chronic sinusitis. After a 36-month follow-up, the survival rate was 97.86%. Additional studies with longer follow-up periods, including the number of zygomatic implants inserted and details of the variations in the surgical techniques used and the impact of the maxillary morphology are still required.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Falha de Restauração Dentária , Arcada Edêntula/reabilitação , Maxila/cirurgia , Procedimentos Cirúrgicos Pré-Protéticos Bucais/métodos , Zigoma/cirurgia , Prótese Dentária Fixada por Implante , Humanos , Resultado do Tratamento
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