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1.
Eur J Oral Sci ; 132(1): e12966, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38062539

RESUMO

The objective of this study was to determine the effects on the colour of adding increasing concentrations of graphene to orthodontic fixed retainer adhesives and to evaluate changes in optical transmission during light curing and the resultant degree of conversion. Two different types of adhesives commonly used for fixed retainers were investigated: A packable composite (Transbond) and a flowable composite (Transbond Supreme). Graphene was added to the adhesives in three different concentrations (0.01, 0.05, and 0.1 wt%). Adhesives without graphene addition were set as control groups. A Minolta colourimeter was used to measure the colour and translucency parameters. Irradiance transmitted during curing was quantified using MARC Light Collector. Fourier-transform infrared spectroscopy was used to record degree of conversion. Data were statistically analysed with the Student's t-test and one-way ANOVA with Tukey's tests (α = 0.05). The findings showed that incorporating graphene darkened the adhesive colour significantly and reduced translucency. As the graphene concentration reached 0.1 wt%, samples became opaque; yet, no adverse effect on degree of conversion was observed. The addition of graphene reduces optical transmission of lingual retainer adhesives; the effect increases with graphene concentration.


Assuntos
Bis-Fenol A-Glicidil Metacrilato , Colagem Dentária , Grafite , Cimentos Dentários , Cimentos de Resina/química , Teste de Materiais , Resinas Compostas/química , Adesivos/química
2.
Dent Mater ; 40(1): 37-43, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37880068

RESUMO

OBJECTIVES: To evaluate the mechanical and antimicrobial properties of boron-containing coating on translucent zirconia (5Y-PSZ). METHODS: 5Y-PSZ discs (Control) were coated with a glaze (Glaze), silver- (AgCoat), or boron-containing (BCoat) glasses. The coatings' antimicrobial potential was characterized using S. mutans biofilms after 48 h via viable colony-forming units (CFU), metabolic activity (CV) assays, and quantification of extracellular polysaccharide matrix (EPS). Biofilm architectures were imaged under scanning electron and confocal laser scanning microscopies (SEM and CLSM). The cytocompatibility was determined at 24 h via WST-1 and LIVE&DEAD assays using periodontal ligament stem cells (PDLSCs). The coatings' effects on properties were characterized by Vickers hardness, biaxial bending tests, and fractography analysis. Statistical analyses were performed via one-way ANOVA, Tukey's tests, Weibull analysis, and Pearson's correlation analysis. RESULTS: BCoat significantly decreased biofilm formation, having the lowest CFU and metabolic activity compared with the other groups. BCoat and AgCoat presented the lowest EPS, followed by Glaze and Control. SEM and CLSM images revealed that the biofilms on BCoat were thin and sparse, with lower biovolume. In contrast, the other groups yielded robust biofilms with higher biovolume. The cytocompatibility was similar in all groups. BCoat, AgCoat, and Glaze also presented similar hardness and were significantly lower than Control. BCoat had the highest flexural strength, characteristic strength and Weibull parameters (σF: 625 MPa; σ0: 620 MPa; m = 11.5), followed by AgCoat (σF: 464 MPa; σ0: 478 MPa; m = 5.3). SIGNIFICANCE: BCoat is a cytocompatible coating with promising antimicrobial properties that can improve the mechanical properties and reliability of 5Y-PSZ.


Assuntos
Anti-Infecciosos , Cerâmica , Teste de Materiais , Boro/farmacologia , Reprodutibilidade dos Testes , Zircônio/farmacologia , Propriedades de Superfície
3.
J Oral Pathol Med ; 52(10): 939-950, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37756121

RESUMO

BACKGROUND: Mucoepidermoid carcinoma is a rare salivary gland malignant tumour. This study aimed to investigate inflammatory and immune signatures of mucoepidermoid carcinoma by identifying potential proteo-transcriptomic biomarkers towards the development of precision immuno-oncology treatment strategies. METHODS: A total of 30 biopsies obtained from patients diagnosed with mucoepidermoid carcinoma between 2013 and 2022 were analysed after H&E staining for scoring of histological inflammatory stroma subtypes and inflammatory hotspots with QuPath. Multiplex immunofluorescence staining and NanoString nCounter PanCancer IO 360™ panel were used to assess stroma and tumour inflammation signatures in high grade mucoepidermoid carcinoma cases in the tumour microenvironment via proteomics and transcriptomics, respectively. RESULTS: Inflammatory cells within the histological inflammatory stroma inflammatory (HIS-INF/hot) tumour neighbourhoods were greater compared to the histological inflammatory stroma-immune desert (HIS-ID/cold) (p = 0.001). A similar trend was observed between treatment non-responders and responders in stroma neighbourhoods (p = 0.0625) and in stroma-to-interface inflammatory hotspots (p = 0.0081), indicating an augmented inflammatory response in hot tumours and non-responders. Furthermore, there were striking differences in the expression of pan-immune leukocyte marker CD45 between responders and non responders particularly in the tumour neighbourhoods (p = 0.0341), but such were not robust for PD-1 and macrophage fractions. Additionally, transcriptomic analysis revealed key differences in leukocyte activation profiles between responders and non-responders. CONCLUSION: This preliminary report unveils the importance of assessing immune leukocyte cellular fractions and pathways for future prognostic biomarker discoveries in mucoepidermoid carcinoma as per the involvement of CD45-driven inflammatory and immune mediators in high grade mucoepidermoid carcinoma in non-responders to treatment. These findings will potentially contribute to the development of novel personalised immunotherapies.


Assuntos
Carcinoma Mucoepidermoide , Neoplasias das Glândulas Salivares , Humanos , Carcinoma Mucoepidermoide/metabolismo , Neoplasias das Glândulas Salivares/patologia , Prognóstico , Glândulas Salivares/metabolismo , Microambiente Tumoral
4.
JBRA Assist Reprod ; 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37768818

RESUMO

OBJECTIVE: We aimed to analyze controlled ovarian stimulation using GnRH antagonist in association with hCG (dual triggering) versus hCG alone (conventional triggering) for final oocyte maturation triggering in a population of unselected Brazilian women. METHODS: This was a retrospective observational study of IVF medical records between January 2019 and March 2020. Data from 335 women with infertility were included for study. All patients were divided into hCG trigger (control group; n=178) and dual trigger (n=157). RESULTS: The number of total oocytes and the number of inseminated oocytes were all significantly higher with the dual trigger protocol compared to hCG-only trigger. However, there is no significant difference in patient age, type of infertility, number of in vitro matured oocytes, trigger day, endometrial thickness, AMH concentration, the number of follicles, the number of mature oocytes and the number of fertilized oocytes. CONCLUSIONS: Using the dual trigger protocol improved the number of total oocytes retrieved and the number of inseminated oocytes.

5.
JBRA Assist Reprod ; 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37579267

RESUMO

OBJECTIVE: To evaluate the impact of body mass index associated with advanced maternal age on pregnancy outcomes. METHODS: A retrospective and observational study that included 808 in vitro fertilization cycles and evaluated: age, weight, height, number of oocytes and mature oocytes, number of embryos and transferred embryos, fertilization and clinical pregnancy rates. Four categories of body mass index: underweight, adequate weight, overweight and obesity. We classified age into 4 categories: 35-37; 38-40; 41-42 and over 42 years of age. The means and rates were calculated and compared between different ages and body mass index groups. RESULTS: For the fresh group, women who achieved clinical pregnancy had a lower mean age than those who did not become pregnant, being the higher the pregnancy rate the lower the age (p<0.0001). After logistic regression analysis for data associated with clinical pregnancy in the fresh group, the number of transferred embryos remained higher in the overweight category (p=0.0001). Overweight and obese women had a significantly higher rate of mature oocytes when compared with adequate weight (p=0.015). Analysis using the ROC curve indicated an area under the curve of 60% (p=0.002) for the fresh group. CONCLUSIONS: The adverse effect of high BMI on clinical pregnancy rates is greater in women under 35 years compared to older women; and age had a higher impact on live birth rate rather than BMI, when the analysis was performed on older women, with the impact of BMI on the probability of having a live birth depending on maternal age.

6.
Dent Mater ; 39(9): 763-769, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37400298

RESUMO

OBJECTIVES: to characterize the effects of graphene oxide (GO) on polymethyl methacrylate's (PMMA) reliability and lifetime. The hypothesis tested was that GO would increase both Weibull parameters and decreased strength degradation over time. METHODS: PMMA disks containing GO (0.01, 0.05, 0.1, or 0.5 wt%) were subjected to a biaxial flexural test to determine the Weibull parameters (m: modulus of Weibull; σ0: characteristic strength; n = 30 at 1 MPa/s) and slow crack growth (SCG) parameters (n: subcritical crack growth susceptibility coefficient, σf0: scaling parameter; n = 10 at 10-2, 10-1, 101, 100 and 102 MPa/s). Strength-probability-time (SPT) diagrams were plotted by merging SCG and Weibull parameters. RESULTS: There was no significant difference in the m value of all materials. However, 0.5 GO presented the lowest σ0, whereas all other groups were similar. The lowest n value obtained for all GO-modified PMMA groups (27.4 for 0.05 GO) was higher than the Control (15.6). The strength degradation predicted after 15 years for Control was 12%, followed by 0.01 GO (7%), 0.05 GO (9%), 0.1 GO (5%), and 0.5 GO (1%). SIGNIFICANCE: The hypothesis was partially accepted as GO increased PMMA's fatigue resistance and lifetime but did not significantly improve its Weibull parameters. GO added to PMMA did not significantly affect the initial strength and reliability but significantly increased PMMA's predicted lifetime. All the GO-containing groups presented higher resistance to fracture at all times analyzed compared with the Control, with the best overall results observed for 0.1 GO.


Assuntos
Grafite , Polimetil Metacrilato , Teste de Materiais , Reprodutibilidade dos Testes , Propriedades de Superfície , Cerâmica
7.
Biomater Biosyst ; 11: 100078, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37283805

RESUMO

Mesenchymal stromal/stem cell (MSC) therapies are currently being explored for dental pulp regeneration. As the therapeutic effects of MSCs in tissue repair are mediated mainly through the release of extracellular vesicles (EVs) including exosomes, we investigated here the cellular processes and molecular mechanisms modulated by MSC exosomes in dental pulp regeneration. Using dental pulp cell (DPC) cultures, we demonstrated that MSC exosomes could increase DPC migration, proliferation, and odontogenic differentiation. The enhancement of these cellular processes was mediated through exosomal CD73-mediated adenosine receptor activation of AKT and ERK signaling. Consistent with these observations, MSC exosomes increased the expression of dentin matrix proteins and promoted the formation of dentin-like tissue and bridge-like structures in a rat pulp defect model. These effects were comparable to that of mineral trioxide aggregate (MTA) treatment. MSC exosomes also yielded recellularized pulp-dentin tissues in the root canal of endodontically-treated human premolars, following subcutaneous implantation in the mouse dorsum. Together, our findings suggest that MSC exosomes could exert a multi-faceted effect on DPC functions including migration, proliferation and odontogenic differentiation to promote dental pulp regeneration. This study provides the basis for development of MSC exosomes as a cell-free MSC therapeutic alternative for pulp-dentin regeneration.

8.
SLAS Technol ; 28(3): 199-209, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37019217

RESUMO

Hyposalivation and severe dry mouth syndrome are the most common complications in patients with head and neck cancer (HNC) after receiving radiation therapy. Conventional treatment for hyposalivation relies on the use of sialogogues such as pilocarpine; however, their efficacy is constrained by the limited number of remnant acinar cells after radiation. After radiotherapy, the salivary gland (SG) secretory parenchyma is largely destroyed, and due to the reduced stem cell niche, this gland has poor regenerative potential. To tackle this, researchers must be able to generate highly complex cellularized 3D constructs for clinical transplantation via technologies, including those that involve bioprinting of cells and biomaterials. A potential stem cell source with promising clinical outcomes to reserve dry mouth is adipose mesenchymal stem cells (AdMSC). MSC-like cells like human dental pulp stem cells (hDPSC) have been tested in novel magnetic bioprinting platforms using nanoparticles that can bind cell membranes by electrostatic interaction, as well as their paracrine signals arising from extracellular vesicles. Both magnetized cells and their secretome cues were found to increase epithelial and neuronal growth of in vitro and ex vivo irradiated SG models. Interestingly, these magnetic bioprinting platforms can be applied as a high-throughput drug screening system due to the consistency in structure and functions of their organoids. Recently, exogenous decellularized porcine ECM was added to this magnetic platform to stimulate an ideal environment for cell tethering, proliferation, and/or differentiation. The combination of these SG tissue biofabrication strategies will promptly allow for in vitro organoid formation and establishment of cellular senescent organoids for aging models, but challenges remain in terms of epithelial polarization and lumen formation for unidirectional fluid flow. Current magnetic bioprinting nanotechnologies can provide promising functional and aging features to in vitro craniofacial exocrine gland organoids, which can be utilized for novel drug discovery and/or clinical transplantation.


Assuntos
Bioimpressão , Xerostomia , Humanos , Animais , Suínos , Glândulas Salivares , Células-Tronco , Regeneração
9.
Curr Microbiol ; 80(3): 89, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723699

RESUMO

Mastitis occurrence in dairy cows is a broad topic that involves several sectors, from antimicrobial resistance and virulence of strains to economic implications and cattle management practices. Here, we assessed the molecular characterization (antimicrobial resistance determinants, virulence genes, sequences type, serotypes, and plasmid types) of 178 Escherichia coli strains isolated from milk samples from cows with clinical mastitis using a genome-based k-mers approach. Of these, 53 (29.8%) showed multidrug resistance by disc diffusion. We selected eight multidrug-resistant mastitis-associated E. coli for whole-genome sequencing and molecular characterization based on raw data using k-mers. We assessed antimicrobial resistance genes, virulence factors, serotypes, Multilocus Sequence Typing (MLST), and plasmid types. The most antimicrobial resistance gene found were blaTEM-1B (7/8), tetA (6/8), strA (6/8), strB (6/8), and qnrB19 (5/8). A total of 25 virulence factors were detected encoding adhesins, capsule, enzymes/proteins, increased serum survival, hemolysin, colicins, and iron uptake. These virulence factors were associated with Extraintestinal Pathogenic E. coli. Three pandemic clones were found: ST10, ST101, and ST69. Two E. coli were assigned in the O117 serogroup and one in the O8:H25 serotype. The most common plasmid groups were IncFII (7/8) and IncFIB (6/8). Our findings contribute to the knowledge of virulence mechanisms, epidemiological aspects, and antimicrobial resistance determinants of E. coli strains obtained from clinical mammary infections of cows.


Assuntos
Infecções por Escherichia coli , Mastite Bovina , Animais , Bovinos , Feminino , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli , Infecções por Escherichia coli/veterinária , Tipagem de Sequências Multilocus , Fatores de Virulência/genética , Genoma
10.
Dent Mater J ; 42(2): 211-217, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36543190

RESUMO

This study investigated the antibacterial efficacy and cytotoxicity of two graphene derivatives -graphene oxide (GO) and reduced graphene oxide (RGO)- against Enterococcus faecalis (E. faecalis) in biofilms formed on hydroxyapatite discs. The viability and biomass of biofilms treated with GO or RGO were evaluated by colony-forming unit counting and crystal violet staining. The morphological features of the biofilms were observed by scanning electron microscopy (SEM), and the bio-volume was quantitatively analyzed by confocal laser scanning microscopy. Furthermore, the cytotoxicity of GO and RGO was evaluated. GO and RGO had similar antibacterial effects on E. faecalis in biofilms (p>0.05). The SEM images showed the ability of GO and RGO to disrupt E. faecalis. Furthermore, GO had significantly higher cytotoxicity than RGO (p<0.05). The results suggest that RGO has the potential to be used as a more effective disinfecting agent than GO since it showed less cytotoxicity while exerting similar antibacterial efficacy.


Assuntos
Grafite , Grafite/farmacologia , Grafite/química , Enterococcus faecalis , Antibacterianos/farmacologia , Biofilmes , Microscopia Confocal
11.
Cell Tissue Res ; 392(2): 499-516, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36576591

RESUMO

Trending three-dimensional tissue engineering platforms developed via biofabrication and bioprinting of exocrine glands are on the rise due to a commitment to organogenesis principles. Nevertheless, a proper extracellular matrix (ECM) microarchitecture to harbor primary cells is yet to be established towards human salivary gland (SG) organogenesis. By using porcine submandibular gland (SMG) biopsies as a proof-of-concept to mimic the human SG, a new decellularized ECM bioassembly platform was developed herein with varying perfusions of sodium dodecyl sulfate (SDS) to limit denaturing events and ensure proper preservation of the native ECM biochemical niche. Porcine SMG biopsies were perfused with 0.01%, 0.1%, and 1% SDS and bio-assembled magnetically in porous polycarbonate track-etched (PCTE) membrane. Double-stranded DNA (dsDNA), cell removal efficiency, and ECM biochemical contents were analyzed. SDS at 0.1% and 1% efficiently removed dsDNA (< 50 ng/mg) and preserved key matrix components (sulfated glycosaminoglycans, collagens, elastin) and the microarchitecture of native SMG ECM. Bio-assembled SMG decellularized ECM (dECM) perfused with 0.1-1% SDS enhanced cell viability, proliferation, expansion confluency rates, and tethering of primary SMG cells during 7 culture days. Perfusion with 1% SDS promoted greater cell proliferation rates while 0.1% SDS supported higher acinar epithelial expression when compared to basement membrane extract and other substrates. Thus, this dECM magnetic bioassembly strategy was effective for decellularization while retaining the original ECM biochemical niche and promoting SMG cell proliferation, expansion, differentiation, and tethering. Altogether, these outcomes pave the way towards the recellularization of this novel SMG dECM in future in vitro and in vivo applications.


Assuntos
Matriz Extracelular Descelularizada , Engenharia Tecidual , Suínos , Humanos , Animais , Engenharia Tecidual/métodos , Matriz Extracelular/metabolismo , Glândulas Salivares , Fenômenos Magnéticos , Tecidos Suporte
12.
J Funct Biomater ; 15(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276474

RESUMO

The liquid extract method is commonly used to evaluate the cytotoxicity and bioactivity of materials. Although ISO has recommended guidelines for test methods, variations in elution period, and shape of samples can influence the biological outcomes. The aim of this study was to investigate the influence of material form and elution period of Biodentine on dental pulp stem cells (DPSCs)' proliferation and mineralization. Biodentine (0.2 g) discs or powder were immersed in culture media (10 mL) for 1, 3 or 7 days (D1, D3 and D7). The eluents were filtered and used to treat DPSC. The calcium release profile and pH were determined. Cell proliferation was evaluated by MTS for 3 days, and mineralization and differentiation were assessed by alizarin red S staining (Ca2+/ng of DNA) and qRT-PCR (MEPE, DSPP, DMP-1, RUNX2, COL-I and OCN) for 14 days. Statistical analysis was performed with a one or two-way ANOVA and post hoc Tukey's test (pH, calcium release and proliferation) or Mann-Whitney test (α = 0.05). pH and calcium ion release of powdered eluents were significantly higher than disc eluents. Powdered eluent promoted extensive cell death, while the disc form was cytocompatible. All disc eluents significantly increased the gene expression and mineralization after 14 days compared to the untreated control. D7 induced less mineralization and differentiation compared to D1 and D3. Thus, the materials' form and elution time are critical aspects to be considered when evaluating the bioactivity of materials, since this binomial can affect positively and negatively the biological outcomes.

13.
J Dent ; 127: 104350, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36341980

RESUMO

OBJECTIVES: To develop a risk of bias tool for pre-clinical dental materials research studies that aims to support reporting of future investigations and improve assessment in systematic reviews. METHODS: A four-stage process following EQUATOR network recommendations was followed, which included project launch, literature review, Delphi process and the tool finalization. With the support of the European Federation of Conservative Dentistry (EFCD) and the Dental Materials Group of the International Association for Dental Research (DMG-IADR), a total of 26 expert stakeholders were included in the development and Delphi vote of the initial proposal. The proposal was built using data gathered from the literature review stage. During this stage, recent systematic reviews featuring dental materials research, and risk of bias tools found in the literature were comprehensively scanned for bias sources. The experts thus reached a consensus for the items, domains and judgement related to the tool, allowing a detailed guide for each item and corresponding signalling questions. RESULTS: The tool features nine items in total, spread between 4 domains, pertaining to the following types of bias: bias related to planning and allocation (D1), specimen preparation (D2), outcome assessment (D3) and data treatment and outcome reporting (D4). RoBDEMAT, as presented, features signalling questions and a guide that can be used for RoB judgement. Its use as a checklist is preferred over a final summary score. CONCLUSION: RoBDEMAT is the first risk of bias tool for pre-clinical dental materials research, supported and developed by a broad group of expert stakeholders in the field, validating its future use. CLINICAL SIGNIFICANCE: This new tool will contribute the study field by improving the scientific quality and rigour of dental materials research studies and their systematic reviews. Such studies are the foundation and support of future clinical research and evidence-based decisions.


Assuntos
Lista de Checagem , Publicações , Revisões Sistemáticas como Assunto , Viés , Materiais Dentários
14.
Dent Clin North Am ; 66(4): 643-657, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216451

RESUMO

Novel technologies and platforms have allowed significant breakthroughs in dental pulp tissue engineering. The development of injectable scaffolds that can be combined with stem cells, growth factors, or other bioactive compounds has enabled the regeneration of functional dental pulps able to secrete dentin in preclinical and clinical studies. Similarly, cell-homing technologies and scaffold-free strategies aim to modulate dental pulp self-regeneration mediated by resident stem cells and can evade some of the technical challenges related to cell-based tissue engineering strategies. This article will discuss emerging technologies and platforms for the clinical applications of dental pulp tissue engineering.


Assuntos
Polpa Dentária , Engenharia Tecidual , Tecidos Suporte , Diferenciação Celular , Dentina , Humanos , Regeneração
15.
Dent Mater ; 38(8): 1385-1394, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35778310

RESUMO

OBJECTIVE: This study aims to characterize the cytotoxicity potential of silver diamine fluoride (SDF) on dental pulp stem cells (DPSC) and gingival equivalents. METHODS: DPSC cultured on 96-well plates was exposed directly to SDF (0.0001-0.01%) and cell viability (IC50) quantified. Effect of SDF on DPSC viability under flow (with dentin barrier) conditions was evaluated using a custom-designed microfluidic "tooth-on-a-chip". Permeability of dentin discs (0.5-1.5 mm thickness) was evaluated using lucifer yellow permeation assay. Dentin discs were treated with 38% SDF (up to 3 h), and cell viability (live/dead assay) of the DPSC cultured in the inlet (unexposed) and outlet (exposed) regions of the pulp channel was evaluated. To assess the mucosal corrosion potential, gingival equivalents were treated with 38% SDF for 3 or 60 min (OECD test guideline 431) and characterized by MTT assay and histomorphometric analysis. RESULTS: DPSC exposed directly to SDF showed a dose-dependent reduction in cell viability (IC50: 0.001%). Inlet channels (internal control) of the tooth-on-a-chip exposed to PBS and SDF-exposed dentin discs showed> 85% DPSC viability. In contrast, the outlet channels of SDF-exposed dentin discs showed a decreased viability of< 31% and 0% (1.5 and ≤1.0 mm thick dentin disc, respectively) (p < 0.01). The gingiva equivalents treated with SDF for 3 and 60 min demonstrated decreased epithelial integrity, loss of intercellular cohesion and corneal layer detachment with significant reduction in intact epithelial thickness (p < 0.05). SIGNIFICANCE: SDF penetrated the dentin (≤1 mm thick) inducing significant death of the pulp cells. SDF also disrupted gingival epithelial integrity resulting in mucosal corrosion.


Assuntos
Cárie Dentária , Gengiva , Dentina , Fluoretos Tópicos , Humanos , Dispositivos Lab-On-A-Chip , Microfluídica , Compostos de Amônio Quaternário/toxicidade , Compostos de Prata
16.
Dent Mater J ; 41(5): 698-704, 2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-35644571

RESUMO

Silver-modified atraumatic restorative technique (SMART) is an emerging restorative technique; however, the effect of silver diamine fluoride (SDF) application on the bond strength of glass ionomer cement (GIC) is unknown. This study aimed to determine if SDF application to sound and artificial caries-affected dentin (ACAD) immediately prior to GIC restoration affected microtensile bond strength (µTBS). Caries was induced on extracted molars using a pH-cycling protocol that was validated against natural caries (similar µTBS). Dentin surfaces were treated with 38% SDF, control groups with de-ionized water and immediately restored. Beam-shaped specimens were sectioned and subjected to tensile forces for µTBS determination. Two hundred and eighty-seven specimens from 40 teeth were tested. SDF application significantly (p<0.001) reduced µTBS in sound dentin (19.00±8.20 MPa vs. 14.60±6.68 MPa), while no difference was found in ACAD. No difference was found in failure mode among groups. For SMART, SDF application on sound dentin before immediate GIC restoration may decrease bond strength.


Assuntos
Colagem Dentária , Cárie Dentária , Cárie Dentária/terapia , Suscetibilidade à Cárie Dentária , Dentina , Fluoretos Tópicos , Cimentos de Ionômeros de Vidro/química , Humanos , Teste de Materiais , Compostos de Amônio Quaternário , Compostos de Prata/química , Resistência à Tração , Água
17.
Int Endod J ; 55 Suppl 2: 446-455, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35218576

RESUMO

With advances in knowledge and treatment options, pulp regeneration is now a clear objective in clinical dental practice. For this purpose, many methodologies have been developed in attempts to address the putative questions raised both in research and in clinical practice. In the first part of this review, laboratory-based methods will be presented, analysing the advantages, disadvantages, and benefits of cell culture methodologies and ectopic/semiorthotopic animal studies. This will also demonstrate the need for alignment between two-dimensional and three-dimensional laboratory techniques to accomplish the range of objectives in terms of cell responses and tissue differentiation. The second part will cover observations relating to orthotopic animal studies, describing the current models used for this purpose and how they contribute to the translation of regenerative techniques to the clinic.


Assuntos
Polpa Dentária , Regeneração , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Modelos Biológicos , Regeneração/fisiologia , Engenharia Tecidual/métodos
18.
Biomater Biosyst ; 8: 100069, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36824379

RESUMO

Candida albicans and methicillin-resistant Staphylococcus aureus (MRSA) synergize in cross-kingdom biofilms to increase the risk of mortality and morbidity due to high resistance to immune and antimicrobial defenses. Biomedical devices and implants made with titanium are vulnerable to infections that may demand their surgical removal from the infected sites. Graphene nanocoating (GN) has promising anti-adhesive properties against C. albicans. Thus, we hypothesized that GN could prevent fungal yeast-to-hyphal switching and the development of cross-kingdom biofilms. Herein, titanium (Control) was coated with high-quality GN (coverage > 99%). Thereafter, mixed-species biofilms (C. albicans combined with S. aureus or MRSA) were allowed to develop on GN and Control. There were significant reductions in the number of viable cells, metabolic activity, and biofilm biomass on GN compared with the Control (CFU counting, XTT reduction, and crystal violet assays). Also, biofilms on GN were sparse and fragmented, whereas the Control presented several bacterial cells co-aggregating with intertwined hyphal elements (confocal and scanning electronic microscopy). Finally, GN did not induce hemolysis, an essential characteristic for blood-contacting biomaterials and devices. Thus, GN significantly inhibited the formation and maturation of deadly cross-kingdom biofilms, which can be advantageous to avoid infection and surgical removal of infected devices.

19.
JBRA Assist Reprod ; 26(2): 214-221, 2022 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-34812600

RESUMO

OBJECTIVE: Is the AMH level correlated with age and number of mature oocytes retrieved from stimulated cycles? METHODS: This descriptive, retrospective, observational study included the data of about 1500 patients submitted to Assisted Reproductive Technology treatments in a clinic in Brazil between July 2012 and April 2019. Patients not submitted to IVF and/or without AMH level records were excluded. The study included women with fertility issues aged 20-50 years submitted to IVF. A total of 733 patients were included. The patients were divided by age into three groups (≤35 years old; 36-39 years old; ≥40 years old). RESULTS: The mean AMH concentration ranged from 2.65 to 1.35 ng/mL and was significantly different between the groups. The mean total number of retrieved oocytes ranged from 9.5 to 5.42 and was significantly different between the groups. The mean number of mature oocytes ranged from 7.14 to 4.58. There was no significant difference in the number of mature oocytes between patients aged 36-39 years and ≥40 years. Negative correlations were observed between patient age and total number of retrieved oocytes (-0.3354) and number of mature oocytes (-0.2839). AMH was negatively correlated with age (-0.3257), although positive correlations with total number of oocytes (0.6702) and number of mature oocytes (0.5770) were observed. CONCLUSIONS: This is the largest study performed with Brazilian patients to correlate AMH levels, age, number of oocytes, and number of mature oocytes from controlled ovarian stimulation cycles. Our data showed that as age increases, AMH levels, number of retrieved oocytes, and number of mature oocytes decrease significantly. However, no significant difference in number of mature oocytes was observed when patients aged 36-39 and ≥40 years were compared. In addition, a positive correlation was found between serum AMH levels and total number of retrieved and mature oocytes from stimulated cycles.


Assuntos
Fatores Etários , Hormônio Antimülleriano , Fertilização In Vitro , Adulto , Hormônio Antimülleriano/sangue , Brasil/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Oócitos , Indução da Ovulação , Estudos Retrospectivos , Adulto Jovem
20.
Tissue Eng Part B Rev ; 28(4): 926-937, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34541887

RESUMO

The role of angiogenesis in health and disease have gained considerable momentum in recent years. Visualizing angiogenic patterns and associated events of surrounding vascular beds in response to therapeutic and laboratory-grade biomolecules has become a commonplace in regenerative medicine and the biosciences. To achieve high-quality imaging for elucidating the molecular mechanisms of angiogenesis, the two-photon excitation fluorescence (2PEF) microscopy, or multiphoton fluorescence microscopy is increasingly utilized in scientific investigations. The 2PEF microscope confers several distinct imaging advantages over other fluorescence excitation microscopy techniques-for the observation of in-depth, three-dimensional vascularity in a variety of tissue formats, including fixed tissue specimens and in vivo vasculature in live specimens. Understanding morphological and subcellular changes that occur in cells and tissues during angiogenesis will provide insights to behavioral responses in diseased states, advance the engineering of physiologically relevant tissue models, and provide biochemical clues for the design of therapeutic strategies. We review the applicability and limitations of the 2PEF microscope on the biophysical and molecular-level signatures of angiogenesis in various tissue models. Imaging techniques and strategies for best practices in 2PEF microscopy will be reviewed. Impact Statement Deep live tissue imaging provides unique opportunities to study angiogenesis and associated events in real-time. In contrast to cross-sectional data provided by conventional methods, two-photon microscopy enables high-resolution tissue imaging, data acquisition over time, real-time visualization of angiogenic events, and reduces the number of animal models used in scientific research. This review provides insights on different two-photon microscopy methods and its application in live and deep tissue imaging of angiogenesis on in vitro and in vivo tissues. We believe that the current trends in imaging can transform the investigation of angiogenesis, cancer research, and biofabrication of vascularized tissues.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica , Medicina Regenerativa , Animais , Estudos Transversais , Microscopia de Fluorescência/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos
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