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1.
Dalton Trans ; 53(14): 6289-6299, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38482899

RESUMO

The solubility of Eu(III) was investigated under undersaturated conditions in acidic, dilute to concentrated MgSO4 and Na2SO4 solutions at T = (22 ± 2) °C. After attaining equilibrium conditions, solid phases were characterized by a multi-method approach, including X-ray diffraction (XRD), Raman and infrared (IR) spectroscopy, quantitative chemical analysis (ICP-OES) and thermogravimetric analysis (TG-DTA). A total of 45 solubility samples were investigated for the systems Eu2(SO4)3-MgSO4-H2O (19 samples) and Eu2(SO4)3-Na2SO4-H2O (26 samples). Eu2(SO4)3·8H2O(cr) was found to control the solubility of Eu(III) in all investigated MgSO4 solutions, as well as in dilute Na2SO4 systems. The transformation of Eu2(SO4)3·8H2O(cr) into the double salt Na2Eu2(SO4)4·2H2O(cr) was observed at mNa2SO4 > 0.01 mol kg-1. The latter phase is characterized by significantly lower solubility. Based on these experimental solubility measurements, thermodynamic and activity models were proposed based on the Pitzer equations considering the full dissociation of the Eu(III) species in MgSO4 and Na2SO4 aqueous solutions, i.e. deliberately excluding Eu(III)-sulfate complex formation. A combination of the geochemical calculation code PhreeSCALE and the parameter estimation code PEST was used to determine the values of solubility products and binary and ternary specific interaction parameters (ß(0)ij, ß(1)ij, Cϕij, θik, Ψijk).

2.
Dalton Trans ; 53(14): 6323-6332, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38487924

RESUMO

A time-resolved laser fluorescence spectroscopy (TRLFS) study was carried out to investigate the Eu(III)-SO4 complexation at room temperature over a wide range of Na2SO4 concentrations (0-2 mol kg-1). Spectroscopic observations confirm the step-wise formation of the aqueous complexes Eu(SO4)+, Eu(SO4)2- and Eu(SO4)33- over the investigated Na2SO4 concentrations. Combining TRLFS data obtained in this study and solubility data reported in Part I of this work for the Eu2(SO4)3-Na2SO4-H2O and Eu2(SO4)3-MgSO4-H2O systems, thermodynamic and activity models were derived based on the SIT and Pitzer formalisms. A combination of the geochemical calculation codes PhreeqC (SIT), PhreeSCALE (Pitzer) and the parameter estimation code PEST was used to determine the solubility products of Eu2(SO4)3·8H2O(cr) and Na2Eu2(SO4)4·2H2O(cr), stability constants of the Eu(III)-SO4 complexes (ß0i), and the specific binary and ternary interaction parameters (εij, ß(0)ij, ß(1)ij, Cϕij, θik, Ψijk) for both activity models. The thermodynamic constants determined in this work are discussed with reference to values available in the literature.

3.
Int J Tuberc Lung Dis ; 28(1): 29-36, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38178289

RESUMO

BACKGROUND: Studies evaluating sputum quality and Xpert® MTB/RIF positivity in the context of active case finding are scarce. We aimed to determine whether sputum quality is associated with Xpert positivity and whether the association differed according to demographic and clinical characteristics.METHODS: A cross-sectional analysis using data from a mass screening programme in Brazilian prisons was conducted from 2017 to 2021. We administered a standardised questionnaire, obtained a chest X-ray and collected a spot sputum sample for Xpert testing. Sputum quality was classified as 'salivary', 'mucoid/mucopurulent' or 'blood-stained'. We used log binomial regressions to estimate the relationship between sputum quality and Xpert positivity, assessing interactions with participant characteristics.RESULTS: Among 4,368 participants for whom sputum quality was assessed, 957 (21.9%) produced salivary specimens, 3,379 (77.4%) had mucoid/mucopurulent sputum and 32 (0.7%) had blood-stained sputum. Xpert positivity was higher among those with mucoid/mucopurulent sputum than among those with salivary samples (12.0% vs. 3.7%). Mucopurulent sputum independently predicted Xpert positivity among individuals with and without symptoms, current smoking and abnormal chest radiographs on CAD4TB.CONCLUSIONS: In our study, sputum appearance independently predicted Xpert positivity, and could be used together with chest X-ray and symptom screening to inform use of Xpert in individual or pooled testing.


Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Humanos , Tuberculose Pulmonar/diagnóstico , Escarro , Estudos Transversais , Sensibilidade e Especificidade
4.
Urologie ; 62(11): 1169-1176, 2023 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-37755575

RESUMO

Standardized structured radiological reporting (SSRB) has been promoted in recent years. The aims of SSRB include that reports be complete, clear, understandable, and stringent. Repetitions or superfluous content should be avoided. In addition, there are advantages in the presentation of chronological sequences, tracking and correlations with structured findings from other disciplines and also the use of artificial intelligence (AI)-based methods. The development of the presented template for SSRB of native computed tomography for urinary stones followed the "process for the creation of quality-assured and consensus-based report templates as well as subsequent continuous quality control and updating" proposed by the German Radiological Society (DRG). This includes several stages of drafts, consensus meetings and further developments. The final version was published on the DRG website ( www.befundung.drg.de ). The template will be checked annually by the steering group and adjusted as necessary. The template contains 6 organ domains (e.g., right kidney) for which entries can be made for a total of 21 different items, mostly with selection windows. If "no evidence of stones" is selected for an organ in the first query, the query automatically jumps to the next organ, so that the processing can be processed very quickly despite the potentially high total number of individual queries for all organs. The German, European, and North American Radiological Societies perceive the establishment of a standardized structured diagnosis of tomographic imaging methods not only in oncological radiology as one of the current central tasks. With the present template for the description of computed tomographic findings for urinary stone diagnostics, we are presenting the first version of a urological template. Further templates for urological diseases are to follow.


Assuntos
Radiologia , Cálculos Urinários , Urolitíase , Urologia , Humanos , Inteligência Artificial , Urolitíase/diagnóstico , Tomografia Computadorizada por Raios X/métodos
5.
Oper Dent ; 48(4): 391-403, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37302146

RESUMO

PURPOSE: Few studies have evaluated the influence of antioxidant agents on the optical and mechanical properties of ceramic laminate veneers after dental bleaching. Thus, this in vitro study aimed to evaluate the influence of antioxidant agents on the color stability and mechanical properties, such as nanohardness (HIT), elastic modulus (Eit*), and degree of conversion (DC) of the bonding interface components after dental bleaching in ceramic laminate veneer luting. METHODS AND MATERIALS: A total of 143 bovine teeth were distributed into experimental groups, according to the procedure method (unbleached or bleached with Whiteness HP Maxx 35%), antioxidant type (control, 10% ascorbic acid, or 10% α-tocopherol), and luting period (24 hours or 14 days) (n=13). The Tetric N-Bond Universal adhesive system and Variolink Esthetic LC resin cement were used as luting agents to lute IPS e.max ceramic restorations (0.6 mm in thickness) to enamel. A UV-visible spectrophotometer was used to assess color stability before and after UV-B artificial accelerated aging for 252, 504, and 756 hours (n=8). The HIT and Eit* of the adhesive and resin cement were measured using a nanohardness tester under a load of 1000 µN, and the DC was measured using a micro-Raman spectrometer (n=5). The color stability and mechanical properties were measured and evaluated by twoway and one-way ANOVA, respectively, and Tukey test (α=0.05). RESULTS: Distinct aging periods exerted significant changes on the color stability of the restorations luted in enamel associated with ascorbic acid, bleached and unbleached, and the bleached enamel under no antioxidant agent action, for the experimental groups evaluated after 14 days (p<0.05). The use of the α-tocopherol antioxidant solution after the bleaching process for 24 hours did not alter the optical and mechanical properties of the adhesive interface of the laminate restorations compared to those of the control group (p>0.05). CONCLUSION: The use of a 10% α-tocopherol antioxidant solution produced promising results, suggesting that it could be mediately used after tooth bleaching to lute ceramic laminate veneers.


Assuntos
Colagem Dentária , Cimentos de Resina , Bovinos , Animais , Cimentos de Resina/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , alfa-Tocoferol , Facetas Dentárias , Cerâmica/uso terapêutico , Cerâmica/química , Ácido Ascórbico , Teste de Materiais , Porcelana Dentária/química , Cor
6.
J Dent Res ; 102(6): 616-625, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36951356

RESUMO

Dentinogenesis imperfecta (DI) is the main orodental manifestation of osteogenesis imperfecta (OI) caused by COL1A1 or COL1A2 heterozygous pathogenic variants. Its prevalence varies according to the studied population. Here, we report the molecular analysis of 81 patients with OI followed at reference centers in Brazil and France presenting COL1A1 or COL1A2 variants. Patients were submitted to clinical and radiographic dental examinations to diagnose the presence of DI. In addition, a systematic literature search and a descriptive statistical analysis were performed to investigate OI/DI phenotype-genotype correlation in a worldwide sample. In our cohort, 50 patients had COL1A1 pathogenic variants, and 31 patients had COL1A2 variants. A total of 25 novel variants were identified. Overall, data from a total of 906 individuals with OI were assessed. Results show that DI was more frequent in severe and moderate OI cases. DI prevalence was also more often associated with COL1A2 (67.6%) than with COL1A1 variants (45.4%) because COL1A2 variants mainly lead to qualitative defects that predispose to DI more than quantitative defects. For the first time, 4 DI hotspots were identified. In addition, we showed that 1) glycine substitution by branched and charged amino acids in the α2(I) chain and 2) substitutions occurring in major ligand binding regions-MLRB2 in α1(I) and MLBR 3 in α2(I)-could significantly predict DI (P < 0.05). The accumulated variant data analysis in this study provides a further basis for increasing our comprehension to better predict the occurrence and severity of DI and appropriate OI patient management.


Assuntos
Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo I , Dentinogênese Imperfeita , Osteogênese Imperfeita , Humanos , Colágeno Tipo I/genética , Dentinogênese Imperfeita/genética , Estudos de Associação Genética , Mutação , Osteogênese Imperfeita/diagnóstico por imagem , Osteogênese Imperfeita/genética
7.
Oper Dent ; 47(6): 648-657, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36251542

RESUMO

This study aimed to evaluate the influence of different dye substances on the effectiveness of bleaching and hydrogen peroxide diffusion (HO). From 300 central bovine incisors, 160 enamel/dentin disks with similar E* values were selected. The specimens were distributed according to the pigment treatment. Aiming to standardize the chromatic change provided by the different pigments, the specimens from each group remained immersed in the pigment solutions for different times (32 specimens per group): DW - distilled water (Control group); BT - black tea; CO - coffee; SD - cola-based soft drink; and RW - red wine. After pigmentation and chromatic change value analysis, only 10 specimens from each group (n=10) were selected, so the chromatic alteration of all groups was similar (ΔE=8.36±0.5). The samples were subjected to bleaching treatment and diffused peroxide was quantified in a visible ultraviolet light spectrophotometer. Two more bleaching sessions were conducted to evaluate ΔE and the Whiteness Index for Dentistry (ΔWID). Concurrently, solutions were prepared with dye agents, and the same ΔE value was obtained in the teeth (ΔE=8.49±0.5). The solutions received a standardized amount of H2O2, being analyzed by a visible ultraviolet light spectrophotometer. Data analysis comprised variance and Tukey's tests (α=0.05). Higher H2O2 diffusion was observed in pigmented groups when compared with DW (p<0.05). The CO and RW groups had the highest ΔE values (p>0.05), meaning greater difficulty in responding to treatment. In relation to ΔWID, RW bleached less than the other groups after the third bleaching session (p<0.05), resembling only the SD group (p=0.467). However, 21 days after ending the bleaching treatment, only RW and CO had the lowest values (p=0.481). Analysis of the solutions revealed that only RW was altered by the peroxide (p<0.05). In conclusion, teeth pigmented with coffee and, mainly, red wine were more resistant to bleaching treatment, although all pigmentations favored increases in transenamel and transdentinal H2O2 penetration.


Assuntos
Clareadores Dentários , Clareamento Dental , Bovinos , Animais , Peróxido de Hidrogênio , Clareadores Dentários/farmacologia , Café , Peróxidos
8.
Cells ; 11(16)2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-36010648

RESUMO

Clinical and experimental data indicate that severe acute respiratory syndrome coronavirus (SARS-CoV)-2 infection is associated with significant changes in the composition and function of intestinal microbiota. However, the relevance of these effects for SARS-CoV-2 pathophysiology is unknown. In this study, we analyzed the impact of microbiota depletion after antibiotic treatment on the clinical and immunological responses of K18-hACE2 mice to SARS-CoV-2 infection. Mice were treated with a combination of antibiotics (kanamycin, gentamicin, metronidazole, vancomycin, and colistin, Abx) for 3 days, and 24 h later, they were infected with SARS-CoV-2 B lineage. Here, we show that more than 80% of mice succumbed to infection by day 11 post-infection. Treatment with Abx had no impact on mortality. However, Abx-treated mice presented better clinical symptoms, with similar weight loss between infected-treated and non-treated groups. We observed no differences in lung and colon histopathological scores or lung, colon, heart, brain and kidney viral load between groups on day 5 of infection. Despite some minor differences in the expression of antiviral and inflammatory markers in the lungs and colon, no robust change was observed in Abx-treated mice. Together, these findings indicate that microbiota depletion has no impact on SARS-CoV-2 infection in mice.


Assuntos
Tratamento Farmacológico da COVID-19 , Microbiota , Enzima de Conversão de Angiotensina 2 , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Modelos Animais de Doenças , Melfalan , Camundongos , Camundongos Transgênicos , Peptidil Dipeptidase A/metabolismo , SARS-CoV-2 , gama-Globulinas
9.
Photodiagnosis Photodyn Ther ; 38: 102795, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35263668

RESUMO

BACKGROUND: Photodynamic therapy (PDT) has shown satisfactory antibacterial effects. However, little information regarding the cytotoxicity potential of PDT using curcumin as a photosensitizer (PS) on fibroblasts are found. The aim of this in vitro study was to evaluate the cytotoxicity of root canal irrigating solutions and photodynamic therapy with curcumin PS on the L-929 cell line. METHODS: Healthy mouse skin fibroblast cells were distributed into the following 7 experimental groups: G1 - culture medium DMEM (control group); G2 - 0.9% sodium chloride; G3 - 2.5% sodium hypochlorite (NaOCl); G4 - 5% NaOCl; G5 - PDT with curcumin PS at 500 mg/L + blue LED; G6 - PDT with curcumin PS at 750 mg/L + blue LED; and G7 - PDT with curcumin PS at 1000 mg/L + blue LED. All experimental groups which underwent PDT action were submitted to blue LED for 4 min, with a wavelength of 480 nm and energy fluency of 75 J/cm². The cultures were maintained under standard cell culture conditions (37°C, 100% humidity, 5% CO2). Cell viability analysis was performed using the colorimetric method to evaluate the periods of 6, 24, and 48 h. Data were subjected to the Kruskal-Wallis test, followed by the Dunn test to compare groups and Friedman test to compare periods (α = 0.05). RESULTS: When comparing the periods, no significant differences were observed for any of the experimental groups analyzed (p > 0.05), except for the NaOCl2.5 group that exhibited higher cell viability at 6 h compared to the period of 48 h (p = 0.0489). In the comparisons of the experimental groups, there were no statistically significant differences between the control group compared to all disinfection protocols, regardless of the period evaluated (p > 0.05), except for the PDT + C1000 group that showed lower cell viability (P < 0.05). CONCLUSIONS: PDT with curcumin at 1000 mg/L was cytotoxic on L-929 fibroblast cell culture. However, laser-activated curcumin at a concentration of 500 mg/L presented no influence on L-929 fibroblast cell viability in in vitro conditions.


Assuntos
Curcumina , Fotoquimioterapia , Animais , Curcumina/farmacologia , Cavidade Pulpar , Camundongos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Irrigantes do Canal Radicular/farmacologia , Irrigantes do Canal Radicular/uso terapêutico , Hipoclorito de Sódio/farmacologia
10.
Oper Dent ; 47(1): 20-30, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34979026

RESUMO

This study aimed to evaluate the effect of the bleaching gel application site on chromatic changes and postoperative sensitivity in teeth. Thirty patients were selected and allocated to three groups (n=10 per group), according to the location of the gel: GI, cervical application; GII, incisal application; and GIII, total facial. The amount and time of application of the 35% hydrogen peroxide (H2O2) gel were standardized. Color changes were analyzed by ΔE and Wid (bleaching index), using the values obtained in the readings conducted on a digital spectrophotometer in the cervical (CRs) and incisal regions (IRs) of the teeth. Spontaneous sensitivity was assessed using the questionnaire, and the stimulated sensitivity caused by the thermosensory analysis (TSA). The analysis occurred in five stages: baseline, after the first, second, and third whitening sessions (S), and 14 days after the end of the whitening, using the linear regression statistical model with mixed effects and post-test by orthogonal contrasts (p<0.05). Although the IR was momentarily favored, at the end of the treatment, the restriction of the application site provided results similar to those obtained when the gel was applied over the entire facial surface. Regarding sensitivity, only the GI showed spontaneous sensitivity. In the TSA, GIII had less influence on the threshold of the thermal sensation. It was concluded that the chromatic alteration does not depend on the gel application site. Spontaneous sensitivity is greater when the gel is concentrated in the cervical region (CR), and the teeth remain sensitized by thermal stimuli even after 14 days.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Dente , Cor , Sensibilidade da Dentina/induzido quimicamente , Sensibilidade da Dentina/tratamento farmacológico , Humanos , Peróxido de Hidrogênio/uso terapêutico , Espectrofotometria , Clareamento Dental/efeitos adversos , Clareamento Dental/métodos , Clareadores Dentários/uso terapêutico , Resultado do Tratamento
11.
J Dent Res ; 101(3): 339-347, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34596449

RESUMO

Temporomandibular joint (TMJ) disorder caused by occlusal trauma is one of the most controversial topics in dentistry. Experimental traumatic occlusion (ETO) induced by metal crowns cemented to mandibular first molars in rats causes a long-lasting nociceptive response. This study aimed to elucidate whether ETO generates an increase in inflammatory mediators in the TMJ. In addition, the impact of ETO on trigeminal ganglia, neurotransmitter release, and satellite glial cell (SGC) activation was investigated. ELISA revealed enhanced inflammatory mediators, including TNF-α, IL-1ß, IL-6, CX3CL1, and ADAM-17 by Western blotting, in periarticular TMJ tissue after 28 d of ETO. In the trigeminal ganglia, ETO groups increased the release of the neurotransmitters substance P and glutamate. Overexpression of the AMPA receptor and upregulation of NMDA were observed in the 0.4- and 0.7-mm ETO groups, respectively, highlighting enhanced neuronal excitation. Increased IL-1ß and COX-2 mRNA levels in the 0.7-mm ETO group confirmed trigeminal ganglia SGC activation. Immunofluorescence and electrophoresis of SGC revealed increased pERK expression in the 0.7-mm ETO group. ERK phosphorylation was shown to be nociceptive specific, with its upregulation occurring in cases of chronic inflammatory pain. Increased PKA mRNA levels were observed in the 0.4-mm ETO group, while CREB mRNA levels were upregulated for both ETO groups. Electrophoresis showed overexpression of sodium channel Nav 1.7 in the 0.7-mm ETO group, while immunofluorescence revealed that Nav 1.7 is expressed in sensory trigeminal ganglia cells. The results of this study suggest that occlusal trauma induces neuroimmune crosstalk, with synthesis of proinflammatory/pronociceptive mediators, which increases neuronal activity in trigeminal ganglia via the activation of an inflammatory response cascade to develop a persistent neuroinflammatory state that leads to central sensitization.


Assuntos
Oclusão Dentária Traumática , Animais , Oclusão Dentária Traumática/metabolismo , Neuroglia/metabolismo , Dor , Ratos , Articulação Temporomandibular/metabolismo , Gânglio Trigeminal/metabolismo
12.
J Am Nutr Assoc ; 41(3): 325-332, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33734035

RESUMO

OBJECTIVE: This study evaluated whether the consumption of a cereal bar combining different phytoestrogens could contribute to the reduction of climacteric symptoms in women. METHODS: This is a clinical, prospective, randomized, simple-blind trial. Forty-eight women, aged 40-65 years, with climacteric symptoms, from a city in southwestern Paraná, Brazil. Participants were randomly assigned into two groups; Phytoestrogens group (PHY = 24), which received for 90-day period a cereal bar containing 80.73 milligrams of soybean and flaxseed phytoestrogens, and the placebo group (PLA = 24), which consumed rice flakes biscuit. Clinical, sociodemographic and anthropometric data were collected and climacteric symptoms were assessed using the Kupperman Index (KI). RESULTS: Forty-three women were analyzed (PHY = 21 and PLA = 22). There were significant reductions in the overall KI score in both groups at the end of the intervention period (p < 0.05). However, the comparison between the groups using linear regression models presented expressively better symptom improvement in the PHY group -6.43 over time (95% CI: -11.6; -1.26; p < 0.05) KI points, with perimenopausal -15.15 (95% CI: -28.95; -1.35) and postmenopausal women -19.34 (95% CI: -33.68; -4.99) showed considerably greater reductions in symptoms at the end of the intervention period compared to premenopausal women. There was also significant reduction in symptoms of hot flushes, paresthesia, sexual complaints, insomnia and melancholy. CONCLUSION: The consumption of a cereal bar containing phytoestrogens was able to improve the symptoms of climacteric syndrome.


Assuntos
Climatério , Isoflavonas , Grão Comestível , Feminino , Humanos , Isoflavonas/farmacologia , Fitoestrógenos/uso terapêutico , Poliésteres/farmacologia , Estudos Prospectivos
13.
Eur J Prosthodont Restor Dent ; 30(2): 87-95, 2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34862865

RESUMO

PURPOSE: To evaluate the adhesion of Streptococcus mutans (S. mutans) on lithium disilicate ceramics, submitted to different intraoral polishing protocols, and the degree of surface smoothness obtained. MATERIALS AND METHODS: Fifty lithium disilicate specimens were divided into 5 groups (n=10): G1-Glaze Group (positive control); G2-Glaze Group + Wear + Glaze; G3-Wear Group (negative control); G4-Ceramisté Wear Group; G5-Optrafine Wear Group. Surface roughness (Ra - µm) was evaluated and the surface characteristics were assessed using a scanning electron microscope (SEM); to assess S. mutans biofilm, the number of cultured cells was evaluated by counting colony-forming units (CFU/mL). The data underwent one-way ANOVA followed by Tukey's test (P⟨.05). RESULTS: There was a significant difference in the surface roughness of all groups compared with G3. There was no significant difference between the G4 and G5 groups that received polishing. G1 group had the lowest mean roughness values. There was a difference in Log values (CFU/mL) between the G3 group and the groups that received glaze (G1 and G2). The G3 group had the highest adhesion of S. mutans (4.53 Log). CONCLUSION: The most effective polishing protocol after wear is glazing, presenting the lowest roughness and CFU/mL values.


Assuntos
Polimento Dentário , Lítio , Biofilmes , Cerâmica , Polimento Dentário/métodos , Porcelana Dentária , Teste de Materiais , Streptococcus mutans , Propriedades de Superfície
14.
Sci Rep ; 11(1): 9266, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33927217

RESUMO

Modifications of the myocardial architecture can cause abnormal electrical activity of the heart. Fibro-fatty infiltrations have been implicated in various cardiac pathologies associated with arrhythmias and sudden cardiac death, such as arrhythmogenic right ventricular cardiomyopathy (ARVC). Here, we report the development of an MRI protocol to observe these modifications at 9.4 T. Two fixed ex vivo human hearts, one healthy and one ARVC, were imaged with an Iterative decomposition with echo asymmetry and least-square estimations (IDEAL) and a magnetization transfer (MT) 3D sequences. The resulting fat fraction and MT ratio (MTR) were analyzed and compared to histological analysis of the three regions ("ARVC triangle") primarily involved in ARVC structural remodeling. In the ARVC heart, high fat content was observed in the "ARVC triangle" and the superimposition of the MTR and fat fraction allowed the identification of fibrotic regions in areas without the presence of fat. The healthy heart exhibited twice less fat than the ARVC heart (31.9%, 28.7% and 1.3% of fat in the same regions, respectively). Localization of fat and fibrosis were confirmed by means of histology. This non-destructive approach allows the investigation of structural remodeling in human pathologies where fibrosis and/or fatty tissue infiltrations are expected to occur.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Coração/diagnóstico por imagem , Tecido Adiposo/patologia , Adulto , Displasia Arritmogênica Ventricular Direita/patologia , Fibrose , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Masculino
15.
Anim Reprod Sci ; 225: 106681, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33421819

RESUMO

The objective was to investigate effects of progesterone (P4) dose on abundance of luteinizing hormone receptor (LHCGR), aromatase (CYP19A1), 3ß-hydroxysteroid dehydrogenase (HSD3B1), and other steroidogenic mRNA transcripts in granulosa cells from dominant follicles. Nellore heifers were assigned to one of six groups: new, first-use controlled internal drug release device (CIDR1) inserted for 5 days (Large-P4-dose-D5; n = 7) or 6 days (Large-P4-dose-D6; n = 8), prostaglandin (PG)F2α administered on D0 and 1 previously-used CIDR (CIDR3) inserted for 5 days (Small- P4-dose-D5; n = 8) or 6 days (Small-P4-dose-D6; n = 8), CIDR1 inserted on D0 and removed plus PGF2α on D5 (Large-P4-dose-proestrus (PE); n = 7), and CIDR3 and PGF2α on D0 and 1, CIDR3 removed plus PGF2α on D5 (Small-P4-dose-PE; n = 7). Duration of P4 treatment (D5 compared to D6) affected abundances of CYP19A1 mRNA transcripts, with there being greater abundances on D6 than D5 (P ≤ 0.05). Heifers treated with the large dose of P4 had a smaller dominant follicle, less serum and intra-follicular estradiol (E2) concentrations (P ≤ 0.05) and lesser LHCGR, CYP19A1, and HSD3B1 transcript abundances (P ≤ 0.05). Heifers treated to induce PE had a larger follicle diameter (P = 0.09), greater intra-follicular E2 concentrations and larger abundances of CYP19A1 mRNA transcript (P ≤ 0.05) than heifers of the D6 group. Overall, treatment with larger doses of P4 resulted in lesser abundances of LHCGR, HSD3B1, and CYP19A1 mRNA transcripts; thus, potentially leading to development of smaller dominant follicles and lesser E2 concentrations.


Assuntos
Bovinos , Sincronização do Estro/efeitos dos fármacos , Progesterona/farmacologia , Receptores do LH/metabolismo , Animais , Aromatase/genética , Aromatase/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Dinoprosta/administração & dosagem , Dinoprosta/análogos & derivados , Dinoprosta/farmacologia , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Progesterona/administração & dosagem , Progesterona Redutase/genética , Progesterona Redutase/metabolismo , Receptores do LH/genética , Esteroide Isomerases/genética , Esteroide Isomerases/metabolismo
16.
Eur Arch Paediatr Dent ; 22(2): 247-255, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32880093

RESUMO

PURPOSE: To evaluate the microhardness, roughness, profilometry and cross-sectional hardness of single increment materials submitted to different challenges. METHODS: Thirty-six disks of each material, Filtek Supreme XTE (FT), Filtek One Bulk Fill (BK), Ketac Molar Easy Mix (KT) and Equia Forte + Coat (EQ) were immersed in saliva, pH cycling and Coke for 15 days. Half of each surface was used as its own control. Superficial microhardness, roughness, perfilometry analysis were performed. All samples were sectioned, embedded in acrylic resins, polished and cross-sectional hardness were made. Data were analyzed by ANOVA and Tukey's test (p < 0.05). RESULTS: The KT presented superficial microhardness superior than EQ. However, in depth, EQ showed superior values. FT, KT suffered the effects of challenges on microhardness values. The highest roughness and wear values were found for KT. RC do not suffer wear. All materials suffered the effects of Coke and pH challenges in depths 10 µm and 60 µm. CONCLUSION: The single increment restorative material that suffered less action on its surface was the bulk-fill resin. The coat present in the hybrid ionomer was able to resist to the immersion actions. In addition, Coke was the most aggressive challenge.


Assuntos
Resinas Compostas , Materiais Dentários , Resinas Acrílicas , Estudos Transversais , Cimentos de Ionômeros de Vidro , Dureza , Humanos , Teste de Materiais , Propriedades de Superfície
17.
Appl Opt ; 60(1): 1-9, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33362066

RESUMO

We show an in-line digital holographic image reconstruction from subsampled holograms with resolution improvement and lensless magnification with high noise immunity by a compressive sensing approach. Our method treats the sensed field as subsampled, low-pass filtered and projected on a Fresnel-Bluestein base in an inverse problem approach to image reconstruction with controlled lensless magnification. So, we have demonstrated by simulation and experimental results that the approach can reconstruct images with quality even when used in holograms obtained from unusual subsampling schemes.

18.
Photodiagnosis Photodyn Ther ; 32: 102031, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33011397

RESUMO

BACKGROUND: Photodynamic therapy (PDT) is used as an adjunct to endodontic treatment to enhance microbial reduction in the root canal system. However, studies evaluating the impact of PDT on the bond strength of the canal sealer to intraradicular dentin are scarce. Thus, this in vitro study aimed to evaluate the influence of photodynamic therapy with methylene blue (MB) photosensitizer (PS) on the bond strength and morphology of the interface between mineral trioxide aggregate (MTA) based endodontic sealer and different thirds of intraradicular dentin. METHODS: Fifty-five bovine incisors were used to simulate experimental endodontic treatments. Biomechanical instrumentation was performed in all root canals and teeth were divided into 5 groups (n = 11): deionized water (control), methylene blue 50 mg/L (MB50WL), methylene blue 100 mg/L (MB100WL), methylene blue 50 mg/L + red laser (MB50L), and methylene blue 100 mg/L + red laser (MB100L). The push-out bond strength of canal sealer to intraradicular dentin was measured using a universal testing machine (n = 8). Representative scanning electron microscopy images were obtained to qualify the fracture patterns. Images of the adhesive interface morphology were obtained using confocal laser scanning microscopy (n = 3). The Kruskal-Wallis test was used to compare data on bond strength between groups, and the Friedman test between thirds (α = 0.05). RESULTS: When comparing root thirds for the MB group with the higher concentration activated by red laser, higher bond strength values was found for the apical third than for the middle third (P = 0.0302). MB in different concentrations, activated by red laser or not, had no influence on the bond strength of distinct thirds of the intraradicular dentin (P > 0.05). As for the adhesive interface morphology, the MB100L group showed a lower qualitatively sealer penetration into the intraradicular dentin. CONCLUSIONS: PDT with MB PS at 50 mg/L had no negative impact on the bond strength of MTA Fillapex canal sealer to intraradicular dentin, being a suitable antisepsis protocol for endodontic treatments.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Óxidos , Fotoquimioterapia , Materiais Restauradores do Canal Radicular , Silicatos , Adesivos , Animais , Bovinos , Cavidade Pulpar , Dentina , Combinação de Medicamentos , Resinas Epóxi , Teste de Materiais , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes
19.
Appl Opt ; 59(20): 5957-5966, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32672739

RESUMO

We applied the Hurst exponent technique to an experimental study of rough metallic surface profiles and the speckle patterns generated by them. Characterization of important statistical properties of the surface profile and speckle patterns were performed. We observed a clear correlation between the Hurst exponent of a surface profile and the one calculated from the associated speckle patterns. Therefore, in principle, information of the Hurst exponent of the profile can be obtained from the Hurst exponent of speckle patterns. Range and sampling analyses were performed in the Hurst exponent calculations showing the robustness of the method. As an additional application, we performed a basic simulation to show that the Hurst exponent is sensitive to surface waviness.

20.
Eur J Prosthodont Restor Dent ; 28(2): 65-74, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32031764

RESUMO

This in vitro study evaluated the effect of the application and previous photoactivation of bonding adhesives in lithium disilicate ceramics. This was achieved by analyzing the bond strength of the cement-ceramic interface, nanohardness and elastic modulus of bonding adhesives and resin cements. The bonding adhesives used were Scotchbond Multi-Purpose (SBMP); Scotchbond Multi-Purpose light-cured (SBMP+LC); Single Bond 2 (SB2); Single Bond 2 light-cured (SB2+LC); Single Bond Universal (SBU) and Single Bond Universal light-cured (SBU+LC). After luting the ceramic in composite resin blocks, all specimens were subjected to 10,000 thermocycles. Sticks were obtained for the microtensile bonding strength test and the nanohardness and elastic modulus of the bonding adhesive and resin cements. Data were submitted to one-way ANOVA and Fishers tests (α =0.05). The results indicated that the bonding strength and mechanical properties were influenced by the interaction of the bonding adhesive and resin cement. For the mechanical properties analyzed, no statistically significant differences were observed between the groups. Single Bond Universal was the only system that was effective with or without previous light activation. For the other adhesive systems, Scotchbond Multi- Purpose and Single Bond 2, the previous light activation was necessary to optimize the bonding strength of the adhesive interface.


Assuntos
Colagem Dentária , Cerâmica , Coroas , Lâmpadas de Polimerização Dentária , Cimentos Dentários , Porcelana Dentária , Teste de Materiais , Cimentos de Resina , Resistência à Tração
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