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1.
Mol Microbiol ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038143

RESUMO

In immunocompetent individuals, Fusarium spp. stands out as the causative agent of onychomycosis, among the non-dermatophyte molds. Despite evidence indicating that Fusarium oxysporum organizes itself in the form of a biofilm causing onychomycosis, there is little literature on the etiopathogenesis of the biofilm on the nail, specifically the signaling molecules present, known as quorum sensing (QS). Thus, this study detected the presence of a molecule related to QS from the ex vivo biofilm of F. oxysporum on human nail and investigated its effect on preformed biofilm in vitro. The detection and physicochemical characterization of a QS molecule, from the extracellular matrix (ECM), was carried out by Fourier transform infrared (FTIR) spectroscopy with an attenuated total reflectance (ATR) accessory and by headspace gas chromatography coupled to mass spectrometry (GC-MS) analyses. Determination of viable cells, cell activity, total biomass, ECM components and scanning electron microscopy (SEM) were performed to evaluate the influence of the QS molecule on the in vitro biofilm of F. oxysporum. The beginning, in the ex vivo biofilm of F. oxysporum on human nails, the volatile organic compound 2-ethyl-1-hexanol (2EH) was detected as a component of QS. Thereafter in vitro analyses, synthetic 2EH was able to modulate the biofilm by stimulating its filament, increasing total biomass and ECM production in terms of total carbohydrates, but with a reduction in total proteins and nucleic acids. We thus evidence, for the first time, the presence of 2EH in the biofilm of F. oxysporum, developed on the human nail, and the in vitro action of this compound as a QS molecule.

2.
Opt Express ; 31(12): 18799-18806, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381311

RESUMO

We report the recent progress on diode-pumped high-power continuous-wave Pr:LiYF4 (YLF) green laser and deep ultraviolet (DUV) laser generation via intracavity frequency doubling. Using two InGaN blue diode lasers as pump source to form a double-end pumping geometry, in this work, we have demonstrated a green laser at 522 nm with a maximum output power of 3.42 W, which is believed to be the highest power ever achieved in all-solid-state Pr3+ lasers in this specific spectral region. Moreover, by intracavity frequency doubling of the achieved green laser, we have further obtained a DUV laser at about 261 nm with a maximum output power of 1.42 W, which is far higher than previous results. The watt-level 261-nm laser paves the way towards the realization of simple and compact DUV source for a variety of applications.

3.
Pharm Dev Technol ; 28(6): 559-570, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37212475

RESUMO

The environment can modify the physiology and body protective function of the skin. Propolis (PRP) and curcumin (CUR) possess important antioxidant and antimicrobial properties, and they can be administered in a combined way and using photodynamic therapy (PDT). Emulgels can control drug release due to the physicochemical properties of the gel and the emulsion. They constitute a good strategy for achieving an improved platform for the combined delivery of PRP and CUR. There are no other studies of emulgels composed of PRP and CUR and their performance as antimicrobial and skin healing using or not PDT. This study aimed to investigate the effect of Carbopol 934 P (C934P), 974 P (C974P) or polycarbophil (PC) on physicochemical stability, antioxidant activity, drug release profile, antimicrobial activity, and ex vivo skin permeation and retention of emulgels containing PRP and CUR. Formulations containing C974P or PC displayed improved stability and antioxidant activity. They displayed activity against Staphylococcus aureus and modified (extended) drug release, governed mainly by non-Fickian anomalous transport. C974P and PC resulted in improved emulgels for combined CUR and PRP delivery, allowing the drugs to cross the stratum corneum, and permeate the epidermis, reaching the dermis. The selected emulgels are candidates for further studies to prove their action and benefits to skin health.


Assuntos
Anti-Infecciosos , Curcumina , Própole , Antioxidantes/farmacologia , Anti-Infecciosos/farmacologia , Géis/química
4.
Exp Dermatol ; 31(11): 1810-1814, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35818750

RESUMO

Fungal biofilms have been involved in the pathogenesis of onychomycosis, but the aspects contributing to this association need to be enlightened. This study aimed to investigate the ability of three different fungi to form biofilm on the nail. All evaluated fungi were able to grow on the nails, using them as the only nutritional source and formed a structure strongly suggestive of biofilms. However, their architecture and morphology were highly contrasting: Candida albicans showed dense growth, exhibited a well-structured community and a large amount of extracellular matrix (ECM), and FTIR-ATR spectroscopy reinforced these findings revealing components suggestive of the biofilm. For Fusarium oxysporum, these events were also observed, but in lower intensity. Furthermore, while Trichophyton rubrum presented a well-organized architecture, the ECM was not visualized. We hypothesize that these findings are related to the symptomatology of onychomycosis. When it is caused by a non-dermatophyte, it usually is accompanied with paronychia, pain, oedema, inflammation and few signals of keratolysis, while dermatophytes are more associated with intense onycholysis and absence of the inflammatory signals. Biofilm seems to be crucial for non-dermatophytes to cause onychomycosis, but not for T. rubrum.


Assuntos
Onicomicose , Onicomicose/microbiologia , Onicomicose/patologia , Unhas , Biofilmes , Trichophyton
5.
Clin Oral Investig ; 26(3): 2635-2643, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34697656

RESUMO

OBJECTIVES: This study aims to evaluate the opalescence (OP) and color stability of composite resins over a period of 180 days and to compare composite resins' OP with enamel's OP. MATERIALS AND METHODS: Twenty human enamel specimens (5.0 × 0.3 mm) and 9 specimens (10.0 × 1.0 mm) of 10 colors of 4 different composite resins (3 M ESPE, FGM, Ivoclar-Vivadent, Miscerium) and one brand of adhesive (3 M ESPE) were made. The results were obtained by measuring the reflectance and transmittance spectra in the visible region. After baseline measurement, composites and adhesive were analyzed after 2, 7, 30, 60, 120, and 180 days. The Lab color coordinates were used in the calculations of the OP parameter and color differences in the CIELab and CIEDE2000 methods. The data were analyzed statistically. RESULTS: The materials tested showed variation and an increase in OP over time. The OP found for enamel was 18.06 ± 2.99, and some resins showed higher results. There was a strong correlation between the coordinate b*T and the OP over time. Enamel Plus was the only one material that presented no color changes during all periods in both color analyses. Filtek Z350 XT, AT, and BT did not show differences in any time when analyzed by CIELAB. CONCLUSIONS: The OP of most composite resins changed during the period of 180 days and was different from the OP of tooth enamel. In general, composites demonstrated small color changes over the period tested, being this characteristic material dependent. CLINICAL RELEVANCE: Natural teeth present different optical properties. Composite resins restorations should present properties similar to natural teeth and it is important that characteristics like color and opalescence remain stable over time.


Assuntos
Resinas Compostas , Iridescência , Cor , Esmalte Dentário , Humanos , Estudos Longitudinais , Teste de Materiais
6.
Pharm Dev Technol ; 27(4): 490-501, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35587564

RESUMO

Thermosensitive bioadhesive formulations can display increased retention time, skin permeation, and improve the topical therapy of many drugs. Acne is an inflammatory process triggered by several factors like the proliferation of the bacteria Propionibacterium acnes. Aiming for a new alternative treatment with a natural source, propolis displays great potential due to its antibiotic, anti-inflammatory, and healing properties. This study describes the development of bioadhesive thermoresponsive platform with cellulose derivatives and poloxamer 407 for propolis skin delivery. Propolis ethanolic extract (PES) was added to the formulations with sodium carboxymethylcellulose (CMC) or hydroxypropyl methylcellulose (HPMC) and poloxamer 407 (Polox). The formulations were characterized as rheology, bioadhesion, and mechanical analysis. The selected formulations were investigated as in vitro propolis release, cytotoxicity, ex vivo skin permeation by Fourier Transform Infrared Photoacoustic Spectroscopy, and the activity against P. acnes. Formulations showed suitable sol-gel transition temperature, shear-thinning behavior, and texture profile. CMC presence decreased the cohesiveness and adhesiveness of formulations. Polox/HPMC/PES system displayed less cytotoxicity, modified propolis release governed by anomalous transport, skin permeation, and activity against P. acnes. These results indicate important advantages in the topical treatment of acne and suggest a potential formulation for clinical evaluation.


Assuntos
Acne Vulgar , Própole , Acne Vulgar/tratamento farmacológico , Celulose , Géis/química , Humanos , Derivados da Hipromelose , Poloxâmero/química
7.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466379

RESUMO

We evaluated a hydroalcoholic extract of Sapindus saponaria L. pericarps (ETHOSS), as a candidate to a topical antifungal medicine for onychomycosis. ETHOSS was produced by extracting the crushed fruits in ethanol. The saponin contents were identified and characterized by electrospray ionization mass spectrometry. We measured the in vitro antifungal activity against three dermatophyte fungi, isolated from onychomycosis: Trichophyton rubrum, T. mentagrophytes, and T. interdigitale, using broth microdilution tests. The minimum fungicide concentration of ETHOSS ranged from 195.31 to 781.25 µg/mL. The cytotoxicity of the crude extract was tested on the HeLa cell line, and its ability to permeate into healthy human nails by photoacoustic spectroscopy and Fourier transformation infrared spectrometer (FTIR) spectroscopy by attenuated total reflection. Besides its strong antifungal activity, ETHOSS showed low cytotoxicity in human cells. It was able to permeate and reach the full thickness of the nail in one hour, without the aid of facilitating vehicles, and remained there for at least 24 h. These results suggest that ETHOSS has great potential for treating onychomycosis.


Assuntos
Álcoois/química , Antifúngicos/farmacologia , Unhas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saponaria/química , Saponinas/farmacologia , Adulto , Feminino , Humanos , Unhas/metabolismo
8.
J Mater Sci Mater Med ; 31(8): 71, 2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32712717

RESUMO

Natural or synthetic biomaterials are increasingly being used to support bone tissue repair or substitution. The combination of natural calcium phosphates with biocompatible alloys is an important route towards the development of new biomaterials with bioperformance and mechanical responses to mimic those of human bones. This article evaluated the structural, physical, mechanical and biological properties of a new mechanical improved nanocomposite elaborated by association of fish biphasic calcium phosphate (BCP) and niobium pentoxide (Nb2O5). The nanocomposite (Nb-BCP) and the pure BCP, used as a positive control, were obtained by powder metallurgy. The density, porosity and microhardness were measured. The structural analysis was determined by X-ray diffraction (XRD) and the biological properties were studied in histological sections of critical size calvaria defects in rats, 7, 15, 30, 45 and 60 days after implantation of disks of both materials. Morphological description was made after scanning electron microscopy (SEM) and optical microscopy analysis. After sintering, the Nb-BCP nanocomposite presented four crystalline phases: 34.36% calcium niobate (CaNb2O6), 21.68% phosphorus niobium oxide (PNb9O25), 42.55% ß-tricalcium phosphate (Ca3(PO4)2) and 1.31% of niobium pentoxide (Nb2O5) and exhibited increases of 17% in density, 66% in Vickers microhardness and 180% in compressive strength compared to pure BCP. In vivo study, showed biocompatibility, bioactivity and osteoconductivity similar to pure BCP. SEM showed the formation of globular accretions over the implanted nanocomposites, representing one of the stages of bone mineralization. In conclusion, the BCP and Nb2O5 formed a nanocomposite exhibiting characteristics that are desirable for a biomaterial, such as bioperformance, higher ß-TCP percentage and improved physical and mechanical properties compared to pure BCP. These characteristics demonstrate the promise of this material for supporting bone regeneration.


Assuntos
Substitutos Ósseos/química , Fosfatos de Cálcio/química , Nióbio/química , Osseointegração , Óxidos/química , Fraturas Cranianas/terapia , Animais , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Substitutos Ósseos/uso terapêutico , Prótese Ancorada no Osso , Interface Osso-Implante/patologia , Fosfatos de Cálcio/síntese química , Fosfatos de Cálcio/uso terapêutico , Modelos Animais de Doenças , Hidroxiapatitas/síntese química , Hidroxiapatitas/química , Hidroxiapatitas/uso terapêutico , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanocompostos/uso terapêutico , Nióbio/uso terapêutico , Osseointegração/efeitos dos fármacos , Óxidos/síntese química , Óxidos/uso terapêutico , Ratos , Ratos Wistar , Fraturas Cranianas/patologia , Difração de Raios X
9.
AAPS PharmSciTech ; 21(6): 209, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728887

RESUMO

Topical administration can enable a more efficient therapy based on the improved bioavailability and patient compliance. Wounds and infections can lead to modifications of skin physiology and body protective function. Propolis (PRP) is utilized for skin protection and treatment. However, PRP extracts do not show suitable rheological characteristics and can cause irritation, pain, ulceration, and healing difficulties when they are administered on the harmed skin. Emulgels composed of Carbopol 934P (C934P) and different vegetable oils have been proposed for propolis extract release and may be a good strategy for topical delivery. The aim of this study was to investigate the bioadhesive properties, PRP release profile, skin permeation, and retention, by Franz's diffusion cell and photoacoustic spectroscopy (PS), of these emulgels. Formulations were composed of C934P and passion fruit oil (PF), sweet almond oil (SA), or andiroba oil (AO). PRP or by-product extracts were added to the systems, drug release profile was investigated, and porcine ear skin was utilized for analyses of bioadhesive properties, skin permeation, and retention. All formulations displayed similar bioadhesive force (0.05-0.07 N); PRP release was modified (prolonged), dependent on formulation composition, and mainly governed by diffusion. PS and analysis using diffusion cell showed that the systems could provide dermal permeation and retention, which was more effective for formulations containing AO. Considering the importance of propolis for many skin therapies, the emulgels containing AO for PRP delivery are worthy of biological studies and further clinical evaluation.


Assuntos
Acrilatos/administração & dosagem , Géis/química , Óleos de Plantas/administração & dosagem , Própole/administração & dosagem , Absorção Cutânea/efeitos dos fármacos , Administração Tópica , Animais , Liberação Controlada de Fármacos , Humanos , Reologia , Suínos
10.
Pharm Dev Technol ; 21(8): 933-942, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26365036

RESUMO

Considering the antioxidant activity of the Trichilia catigua extract (TCE), the aim of the current study was to develop and characterize W/O/W multiple emulsions containing different vegetable oils as a platform to deliver a TCE. The extract displayed antioxidant activity (IC50) of 4.59 µg/mL and total phenol content (TPC) of 50.84%. Formulations were prepared by the phase-inversion emulsification method and analyzed for morphological appearance, pH, conductivity, droplet size and distribution, content of active, rheological properties, in vitro release, skin permeation, and stability. Formulations prepared with canola oil were selected and displayed regular morphology, mean diameter 2.77 µm (without TCE), 3.07 µm with 0.5% and 3.23 µm with 1.0% TCE. Rheometry (flow) showed pseudoplastic behavior with minimal thixotropy for both systems. TCE could be released from emulsions containing 1.0% and 0.5% TCE in a controlled manner for 16 and 23 h, respectively. The emulsions allowed good retention of TCE in the skin (stratum corneum, epidermis, and dermis). In a 180-d assessment of accelerated chemical stability, TPC was more reduced for the emulsions at 40 °C; other parameters remained stable. Multiple emulsions containing TCE were developed, exhibited good characteristics, and may be considered for future investigations as anti-aging formulations for the skin.


Assuntos
Preparações de Ação Retardada/química , Emulsões/química , Meliaceae/química , Animais , Antioxidantes/química , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Tamanho da Partícula , Permeabilidade , Óleos de Plantas/química , Óleo de Brassica napus , Reologia , Pele/metabolismo , Absorção Cutânea , Suínos , Água/química
11.
Pharm Biol ; 54(1): 139-45, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25857682

RESUMO

CONTEXT: Oxidative stress is an important factor modulating skin alterations. Melochia arenosa Benth. (Malvaceae) is a Brazilian plant with antimicrobial activity and antioxidant potential. OBJECTIVE: The objective of this study is to develop a topical formulation containing antioxidant phenolic-rich extract of M. arenosa and to evaluate its skin permeation profile. MATERIALS AND METHODS: Response surface methodology was used to maximize the total phenolic (TP) content of the extract and its antioxidant activity was evaluated by 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and respiratory burst methods. An emulsion containing 1% optimized extract (OE) was developed and employed photoacoustic spectroscopy (PAS) for the determination of its skin permeation profile. The morphology of the skin was studied in histological sections stained with hematoxylin-eosin. RESULTS AND DISCUSSION: The optimum conditions predicted for the major extractive efficiency of the phenolics with 100% ethanol led extraction time 101 h and plant:solvent proportion 1:13.5 (w/v). OE presented TP = 724.6 ± 8.2 mg GAE/g extract and scavenging capacity of DPPH (IC50 value = 11.43 ± 0.14 µg/mL) and ABTS radicals (IC50 value = 35.42 ± 0.48 µg/mL). The production of ROS by neutrophils after stimulation with phorbol miristate acetate was lower when the OE was present in the reaction medium, endorsing its high antioxidant capacity. The data obtained by PAS indicated that the OE present in the emulsion has permeated and was distributed in the whole skin. No histopathological alterations were observed in the histological analysis. CONCLUSION: The formulation developed is a promising tool for skin care and could prevent the damage caused by oxidative stress.


Assuntos
Antioxidantes/metabolismo , Malvaceae/química , Fenóis/metabolismo , Técnicas Fotoacústicas , Extratos Vegetais/metabolismo , Absorção Cutânea , Pele/metabolismo , Administração Cutânea , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/isolamento & purificação , Emulsões , Humanos , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Permeabilidade , Fenóis/administração & dosagem , Fenóis/química , Fenóis/isolamento & purificação , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória/efeitos dos fármacos , Análise Espectral , Fatores de Tempo
12.
Planta Med ; 81(12-13): 1090-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26218337

RESUMO

Diabetes mellitus is a serious public health problem in which a major complication is impaired wound healing. Among the strategies developed to foster tissue repair is the use of medicinal plants. The bark of Stryphnodendron adstringens, which is popularly used as an aid in wound healing, has a documented effect on wound repair in normal rats. This study evaluated the healing action of the crude extract of S. adstringens in diabetic rats, and its chemical content. Compounds present in the crude extract were characterized by mass spectrometry. In diabetic rats (streptozotocin 35 mg/kg), two wounds made in the skin were treated daily for 4, 7, 10, and 14 days with gel containing 1 % crude extract or with base gel. Histological analyses involved the measurement of the length and thickness of the re-epithelialized surface, quantification of the number of cells in mitosis, and types I and III collagen fibers. Also, cutaneous permeation by photoacoustic spectroscopy, and the expression of cyclooxygenase-2 and vascular endothelial growth factor by Western blot were assessed. The crude extract fingerprint showed masses indicating proanthocyanidins. The crude extract mainly stimulated cell migration and proliferation of keratinocytes at the beginning of the treatment in addition to stimulating the replacement of type III collagen fibers by type I collagen fibers at 10 and 14 days. The photoacoustic spectroscopy technique showed that the gel containing 1 % of crude extract permeated through the skin to the dermis, where the crude extract was found. Vascular endothelial growth factor was stimulated after 7 days of treatment with the crude extract and cyclooxygenase-2 at 4, 7, and 10 days. The crude extract of S. adstringens acted in tissue repair in wounds in diabetic rats by stimulating the production of collagen fibers at the wound site. The crude extract favored the formation of a more organized extracellular matrix and filled the entire extent of the wound, and also fostered the upregulation of cyclooxygenase-2 and vascular endothelial growth factor, which are essential to this process. These crude extract actions in diabetic wounds are probably due to the presence of proanthocyanidins.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Fabaceae/química , Cicatrização/efeitos dos fármacos , Animais , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Queratinócitos/efeitos dos fármacos , Masculino , Técnicas Fotoacústicas , Ratos , Ratos Wistar , Pele/efeitos dos fármacos , Pele/metabolismo , Estreptozocina/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Food Technol Biotechnol ; 53(4): 385-396, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27904373

RESUMO

Anthocyanins extracted from the pulp of the fruit of juçara palm (Euterpe edulis Mart.) were microencapsulated with maltodextrin in order to stabilise them. Photoacoustic spectroscopy was used to investigate the photostability of the microencapsulated samples. Complementary differential scanning calorimetry and scanning electron microscopy measurements were also performed. Lyophilised extract had 14 340.2 mg/L of total anthocyanins, and the microencapsulation efficiency of 93.6%. Temperature analysis showed that maltodextrin conferred protection up to 70 °C for 120 min. Scanning electron microscopy showed that the microencapsulated particles had a flake-like morphology with a smooth surface, characteristic of lyophilisation processes. In addition, when added to yogurt, a red colourant was predominant in the samples at pH from 1.5 up to 5.0. Thermal analysis showed a weak interaction between the sample and the encapsulating agent, and photoacoustic data indicated the photostability of the matrix when exposed to light. Yogurts containing microencapsulated anthocyanins showed a more intense pink colour than yogurts treated with pure dye, and sensory analysis demonstrated that they can have good acceptance on the market. Microencapsulation enabled the innovative application of anthocyanins from juçara palm fruit, and complementary techniques allied to the photoacoustic spectroscopy were effective tools for its evaluation.

14.
J Esthet Restor Dent ; 26(4): 279-87, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24974906

RESUMO

OBJECTIVE: To evaluate the color match of different composite resins relative to Vitapan Classical shade guide tab and their respective manufacturers' shade guide tabs as a function of time and storage. MATERIALS AND METHODS: Three enamel shade A2 composite resins were used to fabricate 36 disk-shaped polymerized specimens (12 each), allocated into 2 groups of 6 and stored dry (GD) and in artificial saliva (GS). CIELAB coordinates from shade tabs and resin specimens immediately after polymerization (t0), and 24 hours (t1), 7 (t7), 14 (t14) and 21 (t21) days after polymerization were captured using a colorimeter. Color difference (ΔE00 ) between composite specimens and the reference tabs was calculated using the CIEDE2000 formula. The results were analyzed with repeated measures ANOVA, Tukey's HDS post-hoc test, and Student t test (p ≤ 0.05). RESULTS: Color of the three tested composites relative to Vita and their respective tabs significantly changed as a function of time until t14; however, between t14 and t21, no significant differences were found. No differences in color were found relative to storage at t14 and t21. ΔE00 values of specimens at t14 were significantly higher relative to their respective tabs than to Vitapan tab. CONCLUSIONS: For all brands color changed up to day 14, when it stabilized, regardless of whether composite specimens had been stored in artificial saliva or simply in a box. Vitapan tab presented a better color match than the manufacturers' tabs. CLINICAL SIGNIFICANCE: The results found in this study demonstrated that the Vitapan Classical shade guide tab A2 provided a better color match than the respective shade guide tabs A2 supplied by the composite manufacturers. If custom shade tabs are to be made, however, they could be kept in a box and used as shade references from 14 days after being fabricated, when color stabilizes.


Assuntos
Cor , Resinas Compostas , Restauração Dentária Permanente , Saliva , Colorimetria/instrumentação , Colorimetria/métodos
15.
J Mech Behav Biomed Mater ; 150: 106293, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141362

RESUMO

OBJECTIVES: to evaluate the quality and stability of adhesive interfaces established by self-etching adhesives on caries-affected primary dentin (CAD) treated with glutaraldehyde (GA) or silver diamine fluoride (SDF). METHODS: 42 primary molars were exposed to a microbiological caries-inducing protocol and divided into 6 groups according to the adhesive system (Clearfil SE - CL or FL Bond II - FL) and pretreatment (water, GA or SDF) applied on CAD. One tooth from each group was analyzed for surface modification using infrared spectroscopy. Crowns were restored with resin composite (n = 36) and cut into beams and slices. The beams were subjected to microtensile testing, Raman spectroscopy and SEM after 24 h and 6 months of storage. The slices were analyzed using Micro-Raman spectroscopy to determine the diffusion zone thickness (DZ) in each period. Data were analyzed by ANOVA and Tukey or Kruskal-Wallis and Dunn tests (α = 0.05%). RESULTS: SDF reduced the immediate bond strength for both adhesives. The control groups showed a decrease in BS after 6 months in artificial saliva. GA increased immediate DZ for FL, while SDF had the opposite effect on CL. GA decreased the DZ for FL at 6 months. There was a predominance of adhesive failures with areas of cohesive dentin fractures within control groups. SIGNIFICANCE: Modifications caused by dentin surface treatments may directly affect the performance of adhesive systems and the quality and stability of adhesive restorations.


Assuntos
Adesivos , Colagem Dentária , Adesivos/farmacologia , Glutaral , Suscetibilidade à Cárie Dentária , Dentina , Resistência à Tração , Resinas Compostas/química , Adesivos Dentinários/farmacologia , Adesivos Dentinários/química , Cimentos de Resina/química , Teste de Materiais
16.
Int J Esthet Dent ; 18(1): 26-37, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36734423

RESUMO

PURPOSE: The present study aimed to assess fatigue resistance and color modifications of endodontically treated incisors (ETIs) submitted to internal bleaching and restored using three different techniques. MATERIALS AND METHODS: Forty-five maxillary central incisors received endodontic treatment and were internally bleached. After the completion of bleaching, the ETIs were divided into three groups (n = 15) according to the different restoration procedures: 1) glass-ionomer cement base covered with composite resin (GI); 2) short fiber-reinforced composite resin base with composite resin (SF); 3) composite resin restoration over a fiberglass post (FP). Specimens were subjected to accelerated fatigue testing: frequency of 5 Hz, beginning with a load of 100 N for 5000 cycles and a 25-N load increase applied every 1700 cycles until a load of 1200 N was reached. Samples were loaded until fracture. The Kaplan-Meier survival analysis with the log-rank post hoc test were performed (α = 0.05). Tooth color was measured 4 weeks after the bleaching treatment and again after the final restoration procedure using a spectrophotometer and the Commission Internationale de l'Eclairage (CIE) L*a*b* system. L* values of the specimens were analyzed using the Shapiro-Wilk and paired sample t tests (α = 0.05). RESULTS: All groups showed similar survival mean cycles until failure (P = 0.332) and presented a major number of nonrestorable failures. The GI group presented the lowest number of nonrepairable fractures (GI = 68%, SF = 79%, FP = 86%) and showed the most stable L* value (P = 0.987). CONCLUSIONS: The fatigue survival of internally bleached ETIs was not affected by the restorative technique utilized. Retaining the glass-ionomer base and covering the surface with composite resin should provide optimal color stability.


Assuntos
Técnica para Retentor Intrarradicular , Fraturas dos Dentes , Dente não Vital , Humanos , Incisivo , Resinas Compostas , Cimentos de Ionômeros de Vidro , Ácido Hipocloroso , Dente não Vital/terapia , Análise do Estresse Dentário , Falha de Restauração Dentária
17.
J Mech Behav Biomed Mater ; 143: 105934, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37257313

RESUMO

The aim of this study was to evaluate the influence of various opacities and thicknesses of lithium disilicate on the degree of conversion (DC) of two resin cements and on their bond strength (BS) to the ceramic. Two hundred and forty ceramic samples of lithium disilicate with high translucency (HT), low translucency (LT), and medium opacity (MO) were obtained from IPS e. max CAD in five different thicknesses. Light-cured and dual-cured resin cements were used for DC (n = 9) and BS (n = 8). Cement samples were light-cured under ceramic samples and analyzed using a Raman confocal spectrometer to determine the DC. For BS, resin cement cylinders were fabricated using ceramic samples which were thsen subjected to a microshear bond strength test. The mean values were provided for statistical analysis. The increase in thickness resulted in a decrease in DC for both cements under all experimental conditions, but only affected the BS of the light-cured cement for the MO ceramic. Comparing the opacities, the most translucent ceramics with particular thicknesses exhibited higher DC values than the less translucent ceramics. The LT and MO ceramics with certain thicknesses exhibited the highest BS values than the HT. The dual-cured cement generally showed highest values in both analyses than the light-cured cement. A thicker and more opaque ceramic material can reduce the DC of the cement. The BS decreases with the increasing thickness of the more-opaque ceramics.


Assuntos
Porcelana Dentária , Cimentos de Resina , Cimentos de Resina/química , Teste de Materiais , Cerâmica/química , Propriedades de Superfície
18.
Pharmaceutics ; 15(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36839669

RESUMO

Copaiba oil-resin (COR) extracted from Copaifera reticulata Ducke has been used as a natural chemotherapeutic agent for a wide range of therapeutic applications. This study presents an emulgel design with a high concentration of COR, designed to prevent and treat mastitis. The COR was stabilized in a gel matrix constituted by carbopol C934P and Pluronic® F127 (ECO formulation) ratios. The permeation study of ECO was accessed by Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS). The results reveal a high capacity of ECO to permeate deep skin layers. Dairy cows with a history of mastitis were used as in vivo models and exposed to ECO treatment. Monitoring of the teat's inflammatory response showed that ECO effectively prevents mastitis. Furthermore, the ECO formulation was able to form a thin film gel on the application side, preventing fly proliferation and significantly reducing the pathogen load. This study reveals a drug that can used as an alternative application for mastitis in human or veterinary clinics.

19.
Photodiagnosis Photodyn Ther ; 42: 103498, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36882144

RESUMO

BACKGROUND: Onychomycosis (OM) is a common nail plate disorder caused by dermatophyte molds, yeasts, and non-dermatophyte molds, which use keratin in the nail plate as an energy source. OM is characterized by dyschromia, increased nail thickness, subungual hyperkeratosis, and onychodystrophy, and is typically treated with conventional antifungals despite frequent reports of toxicity, fungal resistance, and OM recurrence. Photodynamic therapy (PDT) with hypericin (Hyp) as a photosensitizer (PS) stands out as a promising therapeutic modality. When excited by a specific wavelength of light and in the presence of oxygen, to lead to photochemical and photobiological reactions on the selected targets. METHODS: OM diagnosis was made in three suspected cases, and the causative agents were identified by classical and molecular methods, and confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). Susceptibility of planktonic cells of the clinical isolates to conventional antifungals and PDT-Hyp was evaluated, and photoacoustic spectroscopy (PAS) of Hyp permeation in nail fragments ex vivo was analyzed. Furthermore, the patients opted to undergo PDT-Hyp treatment and were subsequently followed up. The protocol was approved by the human ethics committee (CAAE, number 14107419.4.0000.0104). RESULTS: The etiological agents of OM in patients ID 01 and ID 02 belonged to the Fusarium solani species complex, being identified as Fusarium keratoplasticum (CMRP 5514) and Fusarium solani (CMRP 5515), respectively. For patient ID 03, the OM agent was identified as Trichophyton rubrum (CMRP 5516). PDT-Hyp demonstrated a fungicidal effect in vitro, with reductions of p3 log10 (p < 0.0051 and p < 0.0001), and the PAS analyses indicated that Hyp could completely permeate through both healthy and OM-affected nails. After four sessions of PDT-Hyp, mycological cure was observed in all three cases, and after seven months, clinical cure was confirmed. CONCLUSION: PDT-Hyp showed satisfactory results in terms of efficacy and safety, and thus can be considered a promising therapy for the clinical treatment of OM.


Assuntos
Doenças da Unha , Onicomicose , Fotoquimioterapia , Humanos , Onicomicose/tratamento farmacológico , Onicomicose/microbiologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Doenças da Unha/tratamento farmacológico
20.
Cells ; 12(14)2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37508528

RESUMO

The application of decellularized scaffolds for artificial tissue reconstruction has been an approach with great therapeutic potential in regenerative medicine. Recently, biomimetic ovarian tissue reconstruction was proposed to reestablish ovarian endocrine functions. Despite many decellularization methods proposed, there is no established protocol for whole ovaries by detergent perfusion that is able to preserve tissue macro and microstructure with higher efficiency. This generated biomaterial may have the potential to be applied for other purposes beyond reproduction and be translated to other areas in the tissue engineering field. Therefore, this study aimed to establish and standardize a protocol for porcine ovaries' decellularization based on detergent perfusion and ultrasonication to obtain functional whole-ovary scaffolds. For that, porcine ovaries (n = 5) were perfused with detergents (0.5% SDS and 1% Triton X-100) and submitted to an ultrasonication bath to produce acellular scaffolds. The decellularization efficiency was evaluated by DAPI staining and total genomic DNA quantification. ECM morphological evaluation was performed by histological, immunohistochemistry, and ultrastructural analyses. ECM physico-chemical composition was evaluated using FTIR and Raman spectroscopy. A cytocompatibility and cell adhesion assay using murine fibroblasts was performed. Results showed that the proposed method was able to remove cellular components efficiently. There was no significant ECM component loss in relation to native tissue, and the scaffolds were cytocompatible and allowed cell attachment. In conclusion, the proposed decellularization protocol produced whole-ovaries scaffolds with preserved ECM composition and great potential for application in tissue engineering.


Assuntos
Ovário , Alicerces Teciduais , Feminino , Suínos , Camundongos , Animais , Alicerces Teciduais/química , Detergentes/farmacologia , Matriz Extracelular/metabolismo , Perfusão
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