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1.
Biomacromolecules ; 25(10): 6748-6761, 2024 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-39305251

RESUMO

Bacterial cellulose (BC) has a long-standing human consumption history in different geographies without any report of adverse effects. Despite its unique textural and functional properties, the use of BC in food products in Europe is still restricted due to concerns over its nanosize. Here, we evaluated the potential uptake of celluloses (from plant and microbial sources, processed using different blenders) by macrophages (differentiated THP-1 cells) and human intestinal epithelial cells (Caco-2 and HT29-MTX cells) without (coculture) or with (triculture) Raji-B cells. A carbohydrate-binding module coupled to a green fluorescent protein was employed to observe cellulose in the cell cultures by confocal laser scanning microscopy and stimulated emission depletion microscopy. The methodology demonstrated excellent sensitivity, allowing detection of single nanocrystals within cells. All celluloses were taken up by the macrophages, without significantly compromising the cell's metabolic viability. The viability of the cocultures was also not affected. Furthermore, no internalization was observed in the triculture cell model that was exposed 24 h to BC and Avicel LM310. When (rarely) detected, cellulose particles were found on the apical side of the membrane. Overall, the obtained results suggest that BC should not be absorbed into the human gut.


Assuntos
Celulose , Células Epiteliais , Macrófagos , Humanos , Celulose/metabolismo , Macrófagos/metabolismo , Células Epiteliais/metabolismo , Trato Gastrointestinal/metabolismo , Células HT29 , Células CACO-2 , Células THP-1 , Técnicas de Cocultura/métodos
2.
Int J Legal Med ; 138(4): 1533-1557, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38538730

RESUMO

INTRODUCTION: Age Estimation has been considered as a human basic right, carried out through the use of tables for dental age assessment based on the chronology of tooth eruption. As such, the final aim of this investigation is to create tables with applicability to the Portuguese population, for the different scoring systems used and combined different statistical approaches. MATERIALS AND METHODS: For this purpose, dental age assessment was achieved in all four third molars, using different scoring systems, in a total sample of 626 orthopantomograms (324 females, 302 males), aged between 12 and 25 years old, from the database population of Lisbon North University Hospital Center, approved by the Ethic Committee. RESULTS: The values of validation showed excellent results both on precision and on reproducibility. Mostly all methods showed statistically significant differences between the estimated age and the chronological age and, therefore, the presence of estimation errors. Kullman's and Mincer's methods are the ones with best applicability in the Portuguese population, in the lower third molars. The reliability measures (sensitivity, specificity and accuracy) values decrease as age increases. CONCLUSION: A combination of the scoring systems as a protocol for dental age assessment in Portuguese nationality was established. Tables, for all the scoring systems used, were made with applicability in the Portuguese population.


Assuntos
Determinação da Idade pelos Dentes , Dente Serotino , Radiografia Panorâmica , Humanos , Determinação da Idade pelos Dentes/métodos , Feminino , Masculino , Criança , Adolescente , Adulto , Adulto Jovem , Dente Serotino/diagnóstico por imagem , Dente Serotino/crescimento & desenvolvimento , Portugal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Clin Oral Investig ; 28(11): 611, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39453555

RESUMO

OBJECTIVE: Self-etching dental adhesives bond with dentin through chemical reactions with calcium. This study assessed bond strength (BS) using microtensile (µTBS) and microshear (µSBS) tests on sound and post-radiotherapy dentin, with dental adhesives containing different functional monomers. METHODS: Sound dentin (SD) and post-radiotherapy irradiated dentin (ID) were tested with two adhesive systems: Clearfil SE Bond (SE, 10-MDP-based) and FL Bond II (FL, containing carboxylic and phosphonic monomers with S-PRG bioactive particles). The tests occurred initially (24 h) and six months later; fracture mode was also analyzed (40x). Ninety-six human molars were randomly assigned (n = 12), and half were irradiated with a 70 Gy radiation dose. For µTBS test, teeth were bonded, restored and sectioned them into beams (0.64 mm2). The µSBS test used filled transparent cylindrical matrices with resin composite and light-cured them after dental adhesive applications. Three-way ANOVA and Tukey's test (p < 0.05) analyzed the data. RESULTS: µTBS showed a significant substrate x adhesive interaction (p < 0.001), while µSBS was significant for all factors (p = 0.006). SE and FL performed better on SD and ID, respectively, in the µTBS test. As for µSBS, SE showed higher values on ID (p < 0.05). Lower BS values occurred for SD-FL and ID-SE after six months. CONCLUSION: Dental adhesive performance varied based on substrate type and test method. FL was more stable for ID in µTBS, while SE excelled in µSBS. CLINICAL RELEVANCE: As post-radiotherapy irradiated dentin becomes more vulnerable, self-etching systems based on functional monomer and bioactive ingredients may exhibit appropriate bonding to this altered substrate.


Assuntos
Colagem Dentária , Análise do Estresse Dentário , Adesivos Dentinários , Teste de Materiais , Cimentos de Resina , Resistência à Tração , Humanos , Adesivos Dentinários/química , Adesivos Dentinários/efeitos da radiação , Cimentos de Resina/química , Cimentos de Resina/efeitos da radiação , Colagem Dentária/métodos , Técnicas In Vitro , Dentina/efeitos da radiação , Resistência ao Cisalhamento , Dente Molar , Propriedades de Superfície
4.
J Prosthet Dent ; 128(3): 496.e1-496.e8, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35985853

RESUMO

STATEMENT OF PROBLEM: Information regarding the masking ability of ceramic crowns over different implant abutment materials is scarce. PURPOSE: The purpose of this in vitro study was to evaluate the masking ability of different monolithic or bilayer ceramic materials with different thicknesses over substrates indicated for implant restorations by using opaque and translucent evaluation pastes. MATERIAL AND METHODS: Disk-shaped specimens, shade A1 (VITA Classic; Ø10×1.5 to 2.5 mm), of different ceramics (a bilayer system [yttria-stabilized zirconia infrastructure+porcelain veneer: Zir+Pc] and monolithic systems [lithium disilicate under low, medium, or high translucency: LtLD, MtLD, or HtLD, respectively, and a high-translucent yttria-stabilized zirconia: HtZir]) were made (n=4). The color difference (ΔE00) was assessed by using the CIEDE2000 formula and considering the different ceramic systems over 5 implant abutment materials (A1 shade Zir [Zir A1]; white Zir [White Zir]; A1 low-translucency lithium disilicate [LD]; polyetheretherketone [PEEK]; and titanium [Ti]) when using 2 different evaluation pastes (translucent or opaque). The control comparison was the restorative material positioned over the Zir A1 substrate with a translucent evaluation paste. Statistical analysis was made by using a 2-way ANOVA and Tukey post hoc tests (α=.05) for ΔE00 data considering the restorative material and luting agent factors as their association. Additionally, ΔE00 data were qualitatively analyzed considering the acceptability and perceptibility thresholds. The translucency parameter (TP00) of each restorative material was evaluated, and data were submitted to 1-way ANOVA and Tukey post hoc tests (α=.05). RESULTS: The most predictable masking ability was seen with Zir+Pc regardless of the evaluation paste used. Nevertheless, under 1.5-mm thickness, Zir+Pc did not adequately mask Ti (ΔE00>1.77). Most monolithic ceramics did not mask discolored substrates (PEEK or Ti, ΔE00>1.77). The exception was HtZir, which presented acceptable masking ability over PEEK at 2.5-mm thickness with both evaluation pastes (ΔE00<1.77). Regardless of the restorative material thickness, Zir+Pc showed the lowest (P<.05) TP00 values (TP00=3.45 at 1.5-mm thickness; TP00=2.00 at 2.5-mm thickness), and HtLD presented the highest (P<.05, TP00=23.50 at 1.5-mm thickness; TP00=13.36 at 2.5-mm thickness). HtZir showed similar TP00 to MtLD at 1.5-mm thickness and similar TP00 to Zir+Pc when used at 2.5-mm thickness (P>.05). CONCLUSIONS: Monolithic ceramics should be used with caution over discolored implant abutments. Bilayer systems (Zir+Pc) were the most predictable approach to adequately masking discolored substrates such as PEEK or Ti. An increased restoration thickness provided higher masking ability for all restorative materials tested.


Assuntos
Implantes Dentários , Porcelana Dentária , Benzofenonas , Cerâmica/uso terapêutico , Cor , Coroas , Cimentos Dentários , Materiais Dentários , Teste de Materiais , Polímeros , Propriedades de Superfície , Titânio , Ítrio , Zircônio
5.
BMC Microbiol ; 21(1): 211, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253188

RESUMO

BACKGROUND: Leishmaniasis is an infectious disease caused by parasites of the genus Leishmania and presents different clinical manifestations. The adverse effects, immunosuppression and resistant strains associated with this disease necessitate the development of new drugs. Nanoparticles have shown potential as alternative antileishmanial drugs. We showed in a previous study the biosynthesis, characterization and ideal concentration of a nanocomposite that promoted leishmanicidal activity. In the present study, we conducted a specific analysis to show the mechanism of action of AgNP-PVP-MA (silver nanoparticle-polyvinylpyrrolidone-[meglumine antimoniate (Glucantime®)]) nanocomposite during Leishmania amazonensis infection in vitro. RESULTS: Through ultrastructural analysis, we observed significant alterations, such as the presence of small vesicles in the flagellar pocket and in the extracellular membrane, myelin-like structure formation in the Golgi complex and mitochondria, flagellum and plasma membrane rupture, and electrodense material deposition at the edges of the parasite nucleus in both evolutive forms. Furthermore, the Leishmania parasite infection index in macrophages decreased significantly after treatment, and nitric oxide and reactive oxygen species production levels were determined. Additionally, inflammatory, and pro-inflammatory cytokine and chemokine production levels were evaluated. The IL-4, TNF-α and MIP-1α levels increased significantly, while the IL-17 A level decreased significantly after treatment. CONCLUSIONS: Thus, we demonstrate in this study that the AgNP-PVP-MA nanocomposite has leishmanial potential, and the mechanism of action was demonstrated for the first time, showing that this bioproduct seems to be a potential alternative treatment for leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmania/efeitos dos fármacos , Nanocompostos/uso terapêutico , Animais , Células Cultivadas , Técnicas In Vitro , Leishmania/fisiologia , Leishmania/ultraestrutura , Macrófagos/parasitologia , Antimoniato de Meglumina/química , Antimoniato de Meglumina/farmacologia , Antimoniato de Meglumina/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Povidona/química , Povidona/farmacologia , Povidona/uso terapêutico , Prata/química , Prata/farmacologia , Prata/uso terapêutico
6.
Macromol Rapid Commun ; 42(19): e2100370, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34254716

RESUMO

Polycationic stepladder polymers containing 5,12-diazapentacenium bistriflate repeat units are made in a two-step sequence of a carbon-nitrogen cross coupling polymerization and subsequent postpolymerization cyclization. The deeply colored products show a rather weak conjugative interaction between the dicationic diazapentacenium repeat units along the polymer chains.


Assuntos
Polímeros , Cátions , Ciclização , Polimerização
7.
J Mater Sci Mater Med ; 32(11): 138, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34716801

RESUMO

Bioresorbable biomaterials can fill bone defects and act as temporary scaffold to recruit MSCs to stimulate their differentiation. Among the different bioresorbable polymers studied, this work focuses on poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(ε-caprolactone) (PCL). Were prepared blends of PHBV and PCL to obtain PHBV based biomaterials with good tenacity, important for bone tissue repair, associated with biocompatible properties of PCL. This study assesses the viability of Vero cells on scaffolds of PHBV, PCL, and their blends and the osteogenic differentiation of mesenchymal stem cells (MSCs). Materials were characterized in surface morphology, DSC and Impact Strength (IS). Vero cells and MSCs were assessed by MTT assay, cytochemical and SEM analysis. MSC osteogenic differentiation was evaluated through alizarin red staining and ALP activity. We found some roughness onto surface materials. DSC showed that the blends presented two distinct melting peaks, characteristic of immiscible blends. IS test confirmed that PHBV-PCL blends is an alternative for increase the tenacity of PHBV. MTT assay showed cells with high metabolic activities on extract toxicity test, but with low activity in the direct contact test. SEM analysis showed spreading cells with irregular and flattened morphology on different substrates. Cytochemical study revealed that MSCs maintained their morphology, although in smaller number for MSCs. The development of nodules of mineralized organic matrix in MSC cultures was identified by alizarin red staining and osteogenic differentiation was confirmed by the quantification of ALP activity. Thus, our scaffolds did not interfere on viability of Vero cells or the osteogenic differentiation of MSCs.


Assuntos
Osso e Ossos , Hidroxibutiratos , Células-Tronco Mesenquimais , Osteogênese , Poliésteres , Alicerces Teciduais , Animais , Ratos , Osso e Ossos/citologia , Diferenciação Celular , Sobrevivência Celular , Chlorocebus aethiops , Hidroxibutiratos/química , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Poliésteres/química , Engenharia Tecidual , Alicerces Teciduais/química , Células Vero
8.
J Prosthet Dent ; 126(1): 119-127, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32636073

RESUMO

STATEMENT OF PROBLEM: Data comparing the fatigue performance of adhesively luted glass or polycrystalline ceramic systems for computer-aided design and computer-aided manufacturing (CAD-CAM) are scarce. PURPOSE: The purpose of this in vitro study was to evaluate and compare the fatigue performance of monolithic crowns manufactured from glass or polycrystalline CAD-CAM ceramic systems adhesively luted to a dentin analog. MATERIALS AND METHODS: Fifty-four pairs of standardized preparations of dentin analog (NEMA Grade G10) and simplified ceramic crowns of 1.5-mm thickness were obtained with 3 ceramic materials: lithium disilicate (LD) glass-ceramic (IPS e.max CAD); zirconia-reinforced lithium silicate (ZLS) glass-ceramic (Vita Suprinity); and translucent yttrium fully stabilized polycrystalline zirconia (Trans YZ) (Prettau Anterior). The simplified crowns (n=15) were adhesively cemented onto the preparations and subjected to step-stress fatigue test (initial load of 400 N, 20 Hz, 10 000 cycles, followed by 100-N increment steps until failure). Collected data (fatigue failure load [FFL] and cycles for failure [CFF]) were submitted to survival analysis with the Kaplan-Meier and Mantel-Cox post hoc tests (α=.05) and to Weibull analysis (Weibull modulus and its respective 95% confidence interval). Failed crowns were submitted to fractography analysis. The surface characteristics of the internal surface (roughness, fractal dimension) of additional crowns were accessed, and the occlusal cement thickness obtained in each luted system was measured. RESULTS: Trans YZ crowns presented the highest values of FFL, CFF, and survival rates, followed by ZLS and LD (mean FFL: 1740 N>1187 N>987 N; mean CFF: 149 000>92 613>73 667). Weibull modulus and cement thickness were similar for all tested materials. LD presented the roughest internal surface, followed by ZLS (mean Ra: 226 nm>169 nm>93 nm). The LD and ZLS internal surfaces also showed higher fractal dimension, pointing to a more complex surface topography (mean fractal dimension: 2.242=2.238>2.147). CONCLUSIONS: CAD-CAM monolithic crowns of Trans YZ show the best fatigue performance. In addition, ZLS crowns also showed better performance than LD crowns.


Assuntos
Cerâmica , Porcelana Dentária , Desenho Assistido por Computador , Coroas , Falha de Restauração Dentária , Análise do Estresse Dentário , Teste de Materiais , Propriedades de Superfície
9.
Cryobiology ; 94: 66-72, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32339491

RESUMO

Type and concentration of cryoprotective agents (CPAs) are important factors which influence the likelihood of a successful ovarian tissue vitrification outcome. In an attempt to address this factor, the present study was conducted to evaluate the impacts of different synthetic polymers (Supercool X-1000, Supercool Z-1000 and PVP K-12) on vitrification of bovine ovarian tissue. From each ovarian pair, fragments were recovered and immediately fixed for analysis (fresh control) or submitted to vitrification, either or not followed by in vitro culture for one or five days. Vitrification was performed using the ovarian tissue cryosystem (OTC) system. The ovarian tissues were intended for histological and viability analysis [Reactive oxygen species (ROS) production and degenerate cells assay (Ethidium homodimer-1)], as well as immunolocalization of AQP3 and AQP9 were measured. The results showed that during almost all the periods after warming, in treatment groups which contain polymer (X-1000, Z-1000 and PVP), the percentage of morphologically normal follicles was the highest in the X-1000 samples. Furthermore, post-thawed X-1000 group revealed stronger labeling for AQP9 in primordial and transitional follicles, when compared with others. However, morphology after cryopreservation did not correlate with follicle viability and function where the levels of degeneration and tissue damage of PVP K-12 group were lower in comparison with X-1000 group and only in PVP K-12 group, ROS level was similar to that of the fresh control group. We believe that in addition to permeating CPAs, the addition of one (Supercool X-1000) or maybe a combination (Supercool X-1000 and PVP K-12) of non-permeating polymers could be useful to improve the outcome for vitrified bovine ovarian tissue.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Ovário , Polímeros/farmacologia , Vitrificação/efeitos dos fármacos , Animais , Bovinos , Feminino
10.
Int J Mol Sci ; 21(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455630

RESUMO

Despite the promising pharmacological properties of curcumin, the transport and effective release of curcumin is still a challenge. The advances in functionalized nanocarriers for curcumin have also been motivated by the anticancer activity of this natural compound, aiming at targeted therapies. Here, stealth (aqueous and solid) magnetoliposomes containing calcium-substituted magnesium ferrite nanoparticles, CaxMg1-xFe2O4 (with x = 0.25, 0.50, 0.75) were developed as nanocarriers for curcumin. The magnetic nanoparticles exhibit superparamagnetic properties and crystalline structure, with sizes below 10 nm. The magnetoliposomes based on these nanoparticles have hydrodynamic diameters around or below 150 nm and a low polydispersity. The influence of an alternating magnetic field (AMF) on drug release over time was evaluated and compared with curcumin release by diffusion. The results suggest the potential of drug-loaded magnetoliposomes as nanocarriers that can be magnetically guided to the tumor sites and act as agents for a synergistic effect combining magnetic hyperthermia and controlled drug release.


Assuntos
Curcumina/administração & dosagem , Liberação Controlada de Fármacos , Lipossomos/química , Nanopartículas de Magnetita/química , Compostos de Cálcio/química , Curcumina/química , Compostos Férricos/química , Compostos de Magnésio/química
11.
Molecules ; 25(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322297

RESUMO

The potential of plant extracts as bioinsecticides has been described as a promising field of agricultural development. In this work, the extracts of Punica granatum (pomegranate), Phytolacca americana (American pokeweed), Glandora prostrata (shrubby gromwell), Ulex europaeus (gorce), Tagetes patula (French marigold), Camellia japonica red (camellia), Ruta graveolens (rue or herb-of-grace) were obtained, purified, and their activity against Spodoptera frugiperda (Sf9) insect cells was investigated. From the pool of over twenty extracts obtained, comprising different polarities and vegetable materials, less polar samples were shown to be more toxic towards the insect cell line Sf9. Among these, a dichloromethane extract of R. graveolens was capable of causing a loss of viability of over 50%, exceeding the effect of the commercial insecticide chlorpyrifos. This extract elicited chromatin condensation and the fragmentation in treated cells. Nanoencapsulation assays of the cytotoxic plant extracts in soybean liposomes and chitosan nanostructures were carried out. The nanosystems exhibited sizes lower or around 200 nm, low polydispersity, and generally high encapsulation efficiencies. Release assays showed that chitosan nanoemulsions provide a fast and total extract release, while liposome-based systems are suitable for a more delayed release. These results represent a proof-of-concept for the future development of bioinsecticide nanoformulations based on the cytotoxic plant extracts.


Assuntos
Agentes de Controle Biológico/química , Praguicidas/química , Extratos Vegetais/química , Folhas de Planta/química , Animais , Camellia , Quitosana/química , Fabaceae , Insetos , Inseticidas/análise , Lipossomos/química , Lithospermum , Nanoestruturas , Phytolacca americana , Punica granatum , Ruta , Solventes , Glycine max/efeitos dos fármacos , Tagetes
12.
Caries Res ; 53(4): 424-430, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30677762

RESUMO

AIM: This study aimed to investigate the prevalence of hypersensitivity in molar-incisor hypomineralization (MIH)-affected molars through a census carried out in 8-year-old schoolchildren. METHODS: Examinations were conducted by a calibrated examiner, using the Nyvad criteria for caries diagnosis and a new criterion for MIH assessment. For hypersensitivity assessment, all MIH-affected molars were included. Nonaffected molars from the same child were used as controls. Air blast reaction was measured using the Visual Analogue Scale (VAS) and the Schiff Cold Air Sensitivity Scale (SCASS) scale, while tactile hypersensitivity was scored using VAS only. Statistical analysis was performed using the Kruskal-Wallis test followed by Dunn's multiple comparisons test for quantitative data. χ2 was used for the comparison of categorical data. RESULTS: In total, 631 children were assessed, of whom 102 had MIH-affected molars (16.1%). Of these, 51.7 and 8.7% presented enamel and dentin carious lesions, respectively. Regarding the number of teeth, 239 molars were MIH affected (59.8%), with 188 (78.7%) being classified as mild (opacities only), 20 (8.4%) as moderate (posteruptive enamel breakdown), and 31 (13%) as severe (posteruptive breakdown involving dentin/atypical restorations). Hypersensitivity was recorded in only one control molar, while the prevalence of hypersensitivity in MIH-affected molars was 34.7%, being of low intensity and more prevalent in moderate (55%) and severe cases (51.6 %) than in mild cases (29.8%, p = 0.008). An association between hypersensitivity and the presence of mild and moderate cases was observed. Although the same association was observed for severe cases, it was not considered a reliable information as 90% of the MIH-affected molars with posteruptive breakdown involving dentin were affected by carious lesions. It is known that dental caries is a confounding factor for the presence of hypersensitivity. CONCLUSIONS: Hypersensitivity was significantly higher in MIH-affected molars than in nonaffected molars, being associated with MIH teeth presenting opacities and posteruptive enamel breakdown.


Assuntos
Hipoplasia do Esmalte Dentário/epidemiologia , Sensibilidade da Dentina/epidemiologia , Criança , Cárie Dentária/epidemiologia , Esmalte Dentário/patologia , Humanos , Incisivo , Dente Molar , Prevalência , Escala Visual Analógica
13.
Acta Odontol Scand ; 77(5): 334-339, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30712422

RESUMO

Oral health is a determinant for quality of life and preventive behaviours such as regular tooth brushing can reduce the risk of a wide spectrum of oral diseases. Adopting preventive behaviours increases the likelihood of being healthy and can be conditioned by demographic and socio-economic factors. OBJECTIVE: This study aims to describe preventive oral hygiene behaviours in the Portuguese population and assess their association with sociodemographic and socioeconomic factors. MATERIAL AND METHODS: A cross-sectional epidemiologic study was developed using data from the first Portuguese National Health Examination Survey. The target population comprised Portuguese community-dwelling residents aged between 25 and 74 years old. The percentage of individuals who brushed their teeth at least twice a day, provided that once was before sleeping, was considered the indicator showing a preventive behaviour, as this is recommended by the General Directorate of Health in Portugal. Poisson regression was used to identify factors independently associated with this behaviour. RESULTS: Sixty-five per cent of the participants reported tooth brushing as recommended. The prevalence of adoption of this preventive behaviour was higher among those living in urban areas and those who have higher educational level. Results show an association between being male and having low educational level with lesser adoption of preventive oral health behaviours. CONCLUSION: These findings suggest a need for integrated approaches, from measures tackling social inequalities to actions focused on improving health literacy. It is also important to expand dental healthcare services and improve effective coverage to increase access for rural population.


Assuntos
Hábitos , Comportamentos Relacionados com a Saúde , Saúde Bucal/estatística & dados numéricos , Higiene Bucal/estatística & dados numéricos , Escovação Dentária/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Prevalência , Qualidade de Vida , Fatores Socioeconômicos
14.
Reprod Fertil Dev ; 29(3): 594-602, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28442066

RESUMO

The aim of the present study was to characterise the ovarian preantral follicle (PF) population and to establish a solid surface vitrification (SSV) process using dimethyl sulfoxide (DMSO) as a cryoprotectant for preservation of ovarian tissue from yellow-toothed cavies (Galea spixii). Ovaries were fixed for PF population analysis or were subjected to the SSV process. The mean (± s.e.m.) PF population per ovarian pair was estimated to be 416.0±342.8. There were 140.0±56.0 (63.4%) and 125.0±58.0 (64.0%) primary follicles on the right and left ovaries, respectively. The proportion of this follicle category was significantly greater than that of other follicle categories (P<0.05). The diameter of follicles (123.7±18.3µm), oocytes (50.1±5.0µm) and nuclei (14.27±2.01µm) was larger for secondary ones when compared with other PFs categories. Most PFs were morphologically normal (94.6%), with light microscopy identifying only a few atretic follicles (5.4%). After SSV, there was a reduction in the proportion of morphologically normal PFs compared with the non-vitrified group (69.5% vs 91.2%, respectively). Transmission electron microscopy revealed preservation of oocytes and granulosa cell membranes and the morphological aspect of follicles; the primary change observed in some vitrified PFs was the presence of vacuoles in the oocytes and granulosa cells cytoplasm and turgid mitochondria. In conclusion, the present study provides an estimative and characterization for the PF population in ovaries of G. spixii. Moreover, we report its PFs cryopreservation using an SSV process.


Assuntos
Criopreservação , Folículo Ovariano/anatomia & histologia , Ovário/anatomia & histologia , Vitrificação , Animais , Feminino , Microscopia Eletrônica de Transmissão , Folículo Ovariano/ultraestrutura , Ovário/ultraestrutura , Roedores
15.
Hum Mol Genet ; 23(24): 6481-94, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25027326

RESUMO

Williams-Beuren syndrome is a developmental multisystemic disorder caused by a recurrent 1.55-1.83 Mb heterozygous deletion on human chromosome band 7q11.23. Through chromosomal engineering with the cre-loxP system, we have generated mice with an almost complete deletion (CD) of the conserved syntenic region on chromosome 5G2. Heterozygous CD mice were viable, fertile and had a normal lifespan, while homozygotes were early embryonic lethal. Transcript levels of most deleted genes were reduced 50% in several tissues, consistent with gene dosage. Heterozygous mutant mice showed postnatal growth delay with reduced body weight and craniofacial abnormalities such as small mandible. The cardiovascular phenotype was only manifested with borderline hypertension, mildly increased arterial wall thickness and cardiac hypertrophy. The neurobehavioral phenotype revealed impairments in motor coordination, increased startle response to acoustic stimuli and hypersociability. Mutant mice showed a general reduction in brain weight. Cellular and histological abnormalities were present in the amygdala, cortex and hippocampus, including increased proportion of immature neurons. In summary, these mice recapitulate most crucial phenotypes of the human disorder, provide novel insights into the pathophysiological mechanisms of the disease such as the neural substrates of the behavioral manifestations, and will be valuable to evaluate novel therapeutic approaches.


Assuntos
Deleção Cromossômica , Cromossomos de Mamíferos , Anormalidades Craniofaciais/genética , Modelos Animais de Doenças , Síndrome de Williams/genética , Animais , Comportamento Animal , Peso Corporal , Encéfalo/patologia , Encéfalo/fisiopatologia , Cardiomegalia/fisiopatologia , Cromossomos Humanos Par 7 , Anormalidades Craniofaciais/patologia , Anormalidades Craniofaciais/fisiopatologia , Feminino , Dosagem de Genes , Genes Letais , Heterozigoto , Humanos , Hipertensão/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Neurônios/patologia , Tamanho do Órgão , Sintenia , Síndrome de Williams/patologia , Síndrome de Williams/fisiopatologia
16.
Phys Chem Chem Phys ; 17(27): 18011-21, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26095537

RESUMO

Nickel ferrite nanoparticles with superparamagnetic behavior at room temperature were synthesized using a coprecipitation method. These magnetic nanoparticles were either covered with a lipid bilayer, forming dry magnetic liposomes (DMLs), or entrapped in liposomes, originating aqueous magnetoliposomes (AMLs). A new and promising method for the synthesis of DMLs is described. The presence of the lipid bilayer in DMLs was confirmed by FRET (Förster Resonance Energy Transfer) measurements between the fluorescent-labeled lipids NBD-C12-HPC (NBD acting as a donor) included in the second lipid layer and rhodamine B-DOPE (acceptor) in the first lipid layer. An average donor-acceptor distance of 3 nm was estimated. Assays of the non-specific interactions of magnetoliposomes with biological membranes (modeled using giant unilamellar vesicles, GUVs) were performed. Membrane fusion between both aqueous and dry magnetoliposomes and GUVs was confirmed by FRET, which is an important result regarding applications of these systems both as hyperthermia agents and antitumor drug nanocarriers.


Assuntos
Compostos Férricos/química , Nanopartículas Metálicas/química , Níquel/química , Lipossomas Unilamelares/química , Transferência Ressonante de Energia de Fluorescência , Bicamadas Lipídicas/química , Magnetismo , Nanopartículas Metálicas/ultraestrutura , Fosfatidiletanolaminas/química , Rodaminas/química
17.
Appl Microbiol Biotechnol ; 99(10): 4131-43, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25820600

RESUMO

On a near future, bio-based economy will assume a key role in our lives. Lignocellulosic materials (e.g., agroforestry residues, industrial/solid wastes) represent a cheaper and environmentally friendly option to fossil fuels. Indeed, following suitable processing, they can be metabolized by different microorganisms to produce a wide range of compounds currently obtained by chemical synthesis. However, due to the recalcitrant nature of these materials, they cannot be directly used by microorganisms, the conversion of polysaccharides into simpler sugars being thus required. This conversion, which is usually undertaken enzymatically, represents a significant part on the final cost of the process. This fact has driven intense efforts on the reduction of the enzyme cost following different strategies. Here, we describe the fundamentals of the enzyme recycling technology, more specifically, cellulase recycling. We focus on the main strategies available for the recovery of both the liquid- and solid-bound enzyme fractions and discuss the relevant operational parameters (e.g., composition, temperature, additives, and pH). Although the efforts from the industry and enzyme suppliers are primarily oriented toward the development of enzyme cocktails able to quickly and effectively process biomass, it seems clear by now that enzyme recycling is technically possible.


Assuntos
Biotecnologia , Celulase/química , Celulose/química , Resíduos/análise
18.
Gen Dent ; 62(1): 62-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24401353

RESUMO

This study sought to investigate dentists' experiences, attitudes, and knowledge in recognizing and reporting suspected cases of child abuse. It was designed as a cross-sectional study across dental practices. Data were collected through a self-administered questionnaire, which was distributed randomly to 500 dentists. The questionnaire investigated characteristics of the population, education concerning child abuse, experience and attitudes in reporting suspected cases, and the ability to recognize signs of abuse. Approximately 60% of the dentists responded to the survey. Among the dentists who participated in the survey, 87% believed that recognizing child abuse is important, however, 63.2% reported that they did not know how to act in such situations, and 44.2% were unaware of the proper child protection authorities to contact. Among the dentists surveyed, 94.7% reported they did not receive enough education concerning child abuse in their undergraduate studies. While 31.3% of dentists suspected child abuse among their patients, 84% reported their suspicions to the proper authorities. The reason cited most often (33.3%) for not reporting suspected abuse was the fear of litigation and its potential impact on their practice. Only 34.2% of dentists demonstrated knowledge about the potential signs of child abuse.


Assuntos
Atitude do Pessoal de Saúde , Maus-Tratos Infantis/diagnóstico , Odontólogos , Papel Profissional , Criança , Proteção da Criança , Estudos Transversais , Odontólogos/psicologia , Feminino , Humanos , Masculino , Papel Profissional/psicologia , Inquéritos e Questionários
19.
Am J Case Rep ; 25: e942872, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885190

RESUMO

BACKGROUND Bartter syndrome is a rare, inherited salt-wasting tubulopathy caused by mutations in 1 of 6 genes that express ion transport channels in the thick ascending limb of nephrons. Excessive prostaglandin E2 and associated hyperreninemic hyperaldosteronism occurs, causing polyhydramnios, polyuria, prematurity, failure to thrive, and characteristic physical features. Hypokalemia, hypochloremic metabolic alkalosis, and, depending on the affected gene, hypercalciuria and nephrocalcinosis are hallmarks of Bartter syndrome. CASE REPORT A 9-month-old male infant, born prematurely due to polyhydramnios, presented in the Emergency Department with dehydration due to incoercible vomiting and significant polyuria. A 6-year-old male infant with a previous history of prematurity due to polyhydramnios was referred to the Pediatric Endocrinology Department due to short stature and notable polydipsia and polyuria. Considering these marked symptoms, both cases triggered suspicion and started workup for arginine-vasopressin insufficiency/resistance. However, during the investigations, a broader clinical revision revealed that both had dysmorphic physical features (triangularly shaped face, prominent forehead, protruding ears, drooping mouth), poor growth, impaired weight gain, and typical biochemical findings (hypokalemic metabolic alkalosis, hypercalciuria, secondary hyperaldosteronism) of Bartter syndrome. Genetic testing confirmed the diagnosis of Bartter syndrome types 1 and type 2, respectively, and this diagnosis allowed proper treatment and significant clinical improvements, personalized follow-up, and genetic counseling for parents desiring further healthy pregnancies. CONCLUSIONS Here, we present clinical and follow-up findings of 2 patients with Bartter syndrome types 1 and 2 discovered upon a broader clinical revision of suspected arginine-vasopressin insufficiency/resistance. We also review pertinent data on diagnosis and management of this challenging syndrome.


Assuntos
Síndrome de Bartter , Humanos , Síndrome de Bartter/diagnóstico , Síndrome de Bartter/genética , Masculino , Lactente , Criança , Arginina Vasopressina
20.
J Forensic Odontostomatol ; 42(2): 60-75, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39244767

RESUMO

Estimating the post-mortem interval (PMI) of human remains based on the histomorphology of dental pulp parameters is promising, but available evidence is scarce and sometimes contradictory without a scientific model. The aim of the study is to characterise the histomorphological changes of dental pulp associated with the decomposition of human remains by a qualitative and quantitative approach. The main aim is to establish a correlation based on post-mortem (PM) dental pulp histomorphology and the PMI, and whether pulp degradation could be an available medico-legal tool for PMI estimation beyond the first week after death (late PMI). The eligible sample consisted of 27 sound teeth from 16 healthy patients aged 16 to 72 years due to orthodontic or oral surgery treatment, to create PMI's simulating the death of the subject as the time elapsed from tooth avulsion. Data collected from patients (sex, date of birth, tooth position, date and hour of the avulsion, date and hour of pulp extraction) were anonymised in accordance with the requirements of Faculty of Dental Medicine of the University of Lisbon. The sample was divided into 9 groups of 3 teeth according to different PMI sets from T0 (baseline) up to 2 weeks (T0, 7, 12, 24, 36, 48, and 72 hours, 1 and 2 weeks). All the dental samples were stored at room temperature up to the time of pulp extraction and then prepared with haematoxylin and eosin stain. High-resolution microscopy was performed to obtain histological images. An operator performed the qualitative evaluation of blood vessels, collagen fibres, and the extra-cellular matrix (ECM) in PM pulps and measured the variation in cells/nuclei density by counting 6 different ROIs (Regions of Interest) for each pulp manually and automatically (quantitative analysis). Qualitative results showed that the degeneration of dental pulp appears 7 hours after death but histological changes in vessels, fibres, and ECM in PM dental pulp are characterised by high variability, consequently it is not possible to generalise the results for early PMIs. Quantitative measurements proved that cell count cannot be standardised due to the presence of superimposed layers of cells and nuclei fragmentation. Odontoblasts did not demonstrate evidence of cellular or nuclear lysis up to 14 PM suggesting their applicability in late PMIs. Future research will focus on late PMIs and different techniques of tooth preparation.


Assuntos
Polpa Dentária , Mudanças Depois da Morte , Humanos , Polpa Dentária/patologia , Adulto , Feminino , Adolescente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Odontologia Legal/métodos , Odontoblastos/patologia , Microscopia , Colágeno/análise
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