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1.
J Dent ; 144: 104918, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461887

RESUMO

OBJECTIVE: To determine the effect of airborne particle abrasion (APA) on micro-tensile bond strength (µTBS) to dentin using different air-abrasion/polishing powders. METHODS: The bonding effectiveness of G2 Bond Universal (G2B), used in etch-and-rinse (E&R) and self-etch mode (SE), was tested on bur-cut dentin and dentin air abraded/polished using six different powders (aluminum oxide 29 µm (AO29) and 53 µm (AO53), aluminum trihydroxide (AT), sodium bicarbonate (SB), sodium bicarbonate soft (SBsoft) and bioactive glass (BG); Velopex). Adhesive-composite resin specimens were immersed in distilled water at 37 °C for one week and cut into microspecimens. Half of the specimens were subjected to 50,000 thermocycles (aged). Immediate and aged µTBS to dentin were measured. Statistical analysis was performed using linear mixed-effects (LME) modeling (p < 0.05). RESULTS: Comparing the aged bond strengths to air-abraded/polished dentin with bur-cut dentin, pretreatment with SB and SBsoft in combination with G2B used in E&R mode, and BG air polishing in combination with both application modes (E&R, SE), resulted in a significantly higher bond strength. Dentin bond strength was only significantly lower when air abraded with AO29 and using G2B in SE mode. Aging did not significantly influence bond strength for both application modes (E&R, SE), except for AO29 and AT-treated dentin, where bond strengths decrea sed significantly using G2B in SE mode. In general, G2B reached significantly higher bond strengths on air-abraded/polished dentin in E&R mode than in SE mode. CONCLUSION: Air-abrasion/polishing did not impair dentin bond strength using G2B, except when dentin was air abraded with AO29 and using G2B in SE mode. Air polishing positively influenced the bond strength to dentin in specific groups. CLINICAL SIGNIFICANCE: APA is safe concerning bonding to dentin. The E&R application mode is preferred using G2B as adhesive on air-abraded/polished dentin. Air polishing with BG positively influenced dentin bond strength for both application methods.


Assuntos
Abrasão Dental por Ar , Resinas Compostas , Colagem Dentária , Adesivos Dentinários , Dentina , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície , Resistência à Tração , Colagem Dentária/métodos , Humanos , Resinas Compostas/química , Adesivos Dentinários/química , Cimentos de Resina/química , Análise do Estresse Dentário , Condicionamento Ácido do Dente/métodos , Polimento Dentário/métodos , Estresse Mecânico , Materiais Dentários/química , Pós
2.
Rev Sci Tech ; 42: 149-160, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37232309

RESUMO

African swine fever (ASF) and classical swine fever (CSF) are transboundary animal diseases (TADs) of pigs. Much effort and resources are regularly put into preventing these diseases' introduction in free areas. Passive surveillance activities bring the highest chances for the early detection of TAD incursions because they are routinely and widely conducted at farms, and because these activities focus on the time between introduction and when the first sample is sent for diagnostic testing. The authors proposed the implementation of an enhanced passive surveillance (EPS) protocol based on collecting data through participatory surveillance actions using an objective and adaptable scoring system to aid the early detection of ASF or CSF at the farm level. The protocol was applied in two commercial pig farms for ten weeks in the Dominican Republic, which is a CSF- and ASF-infected country. This study was a proof of concept, based on the EPS protocol to aid detection of substantial variations in the risk score triggering testing. One of the followed farms had score variation, which triggered testing of the animals, although the test results were negative. The study enables assessment of some of the weaknesses associated with passive surveillance and provides lessons applicable to the problem. Results demonstrate the potential for overcoming some issues preventing the broad application of EPS protocols and suggest that standardised approaches may contribute to the early detection of CSF and ASF introductions.


La peste porcine africaine (PPA) et la peste porcine classique (PPC) sont des maladies animales transfrontalières touchant les porcs. De nombreux efforts et ressources sont régulièrement alloués pour prévenir l'introduction de ces maladies dans des zones indemnes. Les activités de surveillance passive offrent les meilleures perspectives de détection précoce des incursions de maladies animales transfrontalières parce qu'elles sont menées de manière systématique et exhaustive dans les élevages, et parce qu'elles se concentrent sur la période entre l'introduction de la maladie et le moment où le premier échantillon est envoyé au laboratoire pour analyse. Les auteurs proposent la mise en oeuvre d'un protocole de surveillance passive renforcée fondé sur la collecte de données via des actions de surveillance participative utilisant un système de notation objectif et adaptable, en vue d'une détection précoce de la PPA et de la PPC dans les élevages. Ce protocole a été appliqué en République dominicaine, pays infecté par la PPA et la PPC, dans deux élevages porcins commerciaux pendant dix semaines. Cette étude était destinée à valider le principe de la méthode et se fondait sur le protocole de surveillance passive renforcée pour mieux détecter les variations substantielles de la note de risque qui conduisent à tester les animaux. L'un des élevages suivis a présenté une variation de cette note, ce qui a conduit à tester les animaux mais les tests se sont révélés négatifs. L'étude permet d'évaluer certaines des faiblesses associées à la surveillance passive et apporte des enseignements applicables à ce problème. Les résultats illustrent le potentiel de l'approche à surmonter certaines des problématiques empêchant l'application extensive des protocoles de surveillance passive renforcée. Ils suggèrent également que des approches normalisées pourraient contribuer à la détection précoce des cas d'introduction de la PPC et de la PPA.


La peste porcina africana (PPA) y la peste porcina clásica (PPC) son enfermedades animales transfronterizas que afectan al cerdo. Periódicamente se dedican grandes esfuerzos y cuantiosos recursos a evitar que estas enfermedades penetren en zonas que están exentas de ellas. Las actividades de vigilancia pasiva son las más eficaces para detectar con prontitud toda incursión de enfermedades animales transfronterizas, no solo por la regularidad y amplitud con que se llevan a cabo en las explotaciones, sino también porque inciden específicamente en el intervalo entre la penetración de una enfermedad y el momento en que se envía la primera muestra para que sea sometida a pruebas de diagnóstico. Los autores propusieron que se aplicara un protocolo de vigilancia pasiva reforzada que reposaba en la obtención de datos mediante actividades de vigilancia participativa, empleando para ello un sistema objetivo y adaptable de puntuación que ayudaba a detectar con prontitud la presencia en las explotaciones de PPA o PPC. Dicho protocolo fue aplicado a lo largo de diez semanas en dos explotaciones porcinas industriales de la República Dominicana, país en el que ambas infecciones están presentes. El estudio, que sirvió para poner a prueba la idea, pasaba por la aplicación del protocolo de vigilancia pasiva reforzada para ayudar a detectar variaciones sustanciales de la puntuación del nivel de riesgo que activa la realización de pruebas. En una de las explotaciones estudiadas se produjo una variación de la puntuación, cosa que activó la realización de pruebas en los animales, aunque estas arrojaron resultado negativo. El estudio aquí descrito permite evaluar algunos de los puntos débiles de la vigilancia pasiva y extraer enseñanzas aplicables al problema. Los resultados demuestran que es posible salvar algunas de las dificultades que impiden la aplicación generalizada de protocolos de vigilancia pasiva reforzada y dejan pensar que quizá el uso de planteamientos normalizados pueda ayudar a detectar con prontitud los casos de penetración de PPC o PPA.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Peste Suína Clássica , Doenças dos Suínos , Suínos , Animais , Peste Suína Clássica/diagnóstico , Peste Suína Clássica/epidemiologia , Peste Suína Clássica/prevenção & controle , Febre Suína Africana/diagnóstico , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Fatores de Risco , Fazendas , Sus scrofa , Doenças dos Suínos/diagnóstico
3.
Oper Dent ; 48(2): E48-E59, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36928743

RESUMO

OBJECTIVE: The objective of this study was to compare the effect of solvent in universal adhesives (UA) and the application of an extra layer of hydrophobic bonding resin on enamel shear bond strengths (SBS). METHODS AND MATERIALS: Crowns of 224 bovine mandibular incisors were embedded in acrylic resin, wet-polished up to 600-grit silicon carbide paper and assigned to 3 UAs with different solvents (n=32): ethanol-based UA (ADU, AdheSE Universal, Ivoclar Vivadent); isopropanol-based UA (PBU, Prime&Bond Universal, Dentsply Sirona); and acetone-based UA (OPT, OptiBond Universal, Kerr Co). The same UAs were also applied with an extra layer of a hydrophobic bonding resin (HLB, Heliobond, Ivoclar Vivadent): ADU + HLB; PBU + HLB; and OPT + HLB. HLB alone was used as control. Enamel was etched with 37.5% H3PO4 (Kerr Gel Etchant, Kerr Co) for 15 seconds, rinsed with water, and air dried. UAs were applied according to the respective manufacturer's instructions. After adhesive application, composite cylinders (Filtek Z250, 3M Oral Care) were built up and light-cured (40 seconds/increment, 40 J/cm2) keeping the light tip in contact with the mold. Specimens were stored in water for 24 hours (24H) or for 6 months (6M). A knife-edged metallic rod (Ø=2.8-mm semicircular notch) loaded the composite cylinders until fracture. Mode of failure was analyzed with optical microscopy (40×). Statistics included twoway analysis of variance (ANOVA; adhesive strategy and water storage) and Tukey honestly significant difference (HSD) post hoc test (α=95%). RESULTS: Mean enamel SBS ranged from 3.6 (±2.2) MPa (HLB/6M) to 24.7 (±7.1) MPa (ADU + HLB/6M). ANOVA revealed significant differences for adhesive strategy (p≤0.001) but no significant differences for water storage (p>0.05). All UAs resulted in similar mean enamel SBS with or without an extra layer of HLB at 24H. After 6M, only ADU resulted in higher enamel SBS when an extra layer of HLB was applied. All UAs resulted in higher mean enamel SBS than HLB (control). Most failures were adhesive exception for PBU/HLB/6M, which had mostly mixed failures. CONCLUSIONS: UAs resulted in statistically higher enamel SBS than the nonsolvated hydrophobic bonding resin (control), regardless of the solvent in their composition. Application of an extra layer of hydrophobic bonding resin over UAs did not improve mean enamel SBS for isopropanol- and acetone-based UAs but did improve mean enamel SBS for the ethanol-based UA after 6M. Resin composite bonding to enamel using a hydrophobic bonding resin alone is not recommended.


Assuntos
Colagem Dentária , Cimentos Dentários , Animais , Bovinos , Cimentos Dentários/uso terapêutico , Acetona , Adesivos Dentinários/química , 2-Propanol , Colagem Dentária/métodos , Resinas Compostas/uso terapêutico , Resinas Compostas/química , Cimentos de Resina/uso terapêutico , Cimentos de Resina/química , Solventes , Esmalte Dentário , Água/química , Etanol , Teste de Materiais , Resistência ao Cisalhamento , Dentina
4.
Braz J Biol ; 83: e265791, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36651451

RESUMO

Amazonian commercial fishing is artisanal, and landings can be influenced by the flood pulse, the consumer market, the level of exploitation of species, habitat quality and vegetation cover. In this study, landscape variables and the river level were evaluated as possible drivers in the composition of catches landed in three regions of the Solimões-Amazon River. Fish landing data were collected in the upper and lower Solimões River and lower Amazon River. Fishing locations were mapped with information from fishers, civil defense departments and from the literature. Information related to river level and landscape was acquired from databases available online. Maps with the the radius of action of the fishing fleet and the quantification of landscape variables were made for periods of high and low-water, and non-metric multidimensional scaling analysis (nMDS) with catches by species, by region and hydrological period were performed. The largest operating radius of the fishing fleet was of 1,028 km and was identified in the lower Amazon River, which is probably due to the larger size of the consumer market, vessel characteristics and level of exploitation of the species near the landing center. The proportion of vegetation cover was reduced from 87% in the upper stretches of the Solimões River to 46% in the lower stretches. The upper and lower Solimões River regions presented a greater variety of species in the composition of landings. It was identified that the composition of landings between the three analyzed regions possibly varied according to the availability of habitats, indicating the importance of landscape variables for fish landings.


Assuntos
Ecossistema , Pesqueiros , Animais , Rios , Inundações
5.
Ann Oncol ; 34(4): 377-388, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36709038

RESUMO

BACKGROUND: We evaluated whether tissue tumor mutational burden (tTMB) and STK11, KEAP1, and KRAS mutations have clinical utility as biomarkers for pembrolizumab monotherapy versus platinum-based chemotherapy in patients with programmed death ligand 1 (PD-L1)-positive (tumor proportion score ≥1%) advanced/metastatic non-small-cell lung cancer (NSCLC) without EGFR/ALK alterations in the phase III KEYNOTE-042 trial. PATIENTS AND METHODS: This retrospective exploratory analysis assessed prevalence of tTMB and STK11, KEAP1, and KRAS mutations determined by whole-exome sequencing of tumor tissue and matched normal DNA and their associations with outcomes in KEYNOTE-042. Clinical utility of tTMB was assessed using a prespecified cut point of 175 mutations/exome. RESULTS: Of 793 patients, 345 (43.5%) had tTMB ≥175 mutations/exome and 448 (56.5%) had tTMB <175 mutations/exome. No association was observed between PD-L1 expression and tTMB. Continuous tTMB score was associated with improved overall survival (OS) and progression-free survival among patients receiving pembrolizumab (Wald test, one-sided P < 0.001) but not those receiving chemotherapy (Wald test, two-sided P > 0.05). tTMB ≥175 mutations/exome was associated with improved outcomes for pembrolizumab versus chemotherapy, whereas tTMB <175 mutations/exome was not {OS: hazard ratio, 0.62 [95% confidence interval (CI) 0.48-0.80] and 1.09 (95% CI 0.88-1.36); progression-free survival: 0.75 (0.59-0.95) and 1.27 (1.04-1.55), respectively}. Improved OS [hazard ratio (95% CI)] for pembrolizumab versus chemotherapy was observed regardless of STK11 [STK11 mutant (n = 33): 0.37 (0.16-0.86), STK11 wild-type (n = 396): 0.83 (0.65-1.05)]; KEAP1 [KEAP1 mutant (n = 64): 0.75 (0.42-1.35), KEAP1 wild-type (n = 365): 0.78 (0.61-0.99)], or KRAS [KRAS mutant (n = 69): 0.42 (0.22-0.81); KRAS wild-type (n = 232): 0.86 (0.63-1.18)] mutation status. CONCLUSION: tTMB with a cut point of ≥175 mutations/exome is a potential predictive biomarker for pembrolizumab monotherapy for advanced/metastatic PD-L1 tumor proportion score ≥1% NSCLC. Pembrolizumab is a standard first-line treatment in this setting regardless of STK11, KEAP1, or KRAS mutation status.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Estudos Retrospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/uso terapêutico , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
6.
Biochimie ; 208: 86-92, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36586564

RESUMO

Leishmania parasites have an oxidative and chemical defense mechanism called trypanothione system (T[SH]2), the most abundant thiol system in trypanosomatids. This system has a central role in processing pentavalent antimony and resistance has been related to a better capacity to metabolize it through the activation of T[SH]2 enzymatic cascade. A biochemical approach was applied to assess the effect of trivalent (SbIII) and pentavalent antimony (SbV) on Trypanothione Reductase (TR) activity of two Leishmania (Viannia) braziliensis clinical isolates, which were labeled as responder (R) and non-responder (NR) after patient treatment with Glucantime®. Both isolates were characterized based on in vitro susceptibility to SbIII and SbV and trypanothione reductase (TR) activity. SbIII and SbV discriminated susceptibility profiles in all parasite forms, since isolate NR had significantly higher EC50 values than isolate R. Differences were observed in TR activity between promastigotes, axenic amastigotes and intracellular amastigotes: R (0.439 ± 0.009, 0.103 ± 0.01 and 0.185 ± 0.01AU.min-1.µg of protein-1) and NR (1.083 ± 0.04, 0.914 ± 0.04 and 0.343 ± 0.04 AU. min-1.µg of protein-1), respectively. Incubation with SbIII and SbV using each form EC50 value caused a time-dependent differential effect on TR activity suggesting that oxidative defense is related to the antimony susceptibility phenotype. Data gathered here shows a biochemical approach able to discriminate two L. (V.) braziliensis clinical isolates measurements TR activity of promastigotes, axenic amastigotes and intracellular amastigotes.


Assuntos
Leishmania braziliensis , Leishmania , Antimônio/farmacologia , Antimoniato de Meglumina
7.
Oper Dent ; 47(2): 131-137, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35290465

RESUMO

This clinical case describes an esthetic rehabilitation of a young patient presenting with erosive tooth wear. The etiological factors for the erosion in this clinical case was excessive carbonated beverages and lemon water intake. The patient's main complaint was the yellowish aspect of her smile. The treatment procedure selected was direct resin composite veneers in the six maxillary anterior teeth. A three-year follow-up of the case is presented. The three-year follow-up showed a successful clinical performance of the treatment procedure after a finishing/polishing protocol.


Assuntos
Facetas Dentárias , Erosão Dentária , Resinas Compostas/uso terapêutico , Feminino , Seguimentos , Humanos , Erosão Dentária/etiologia , Erosão Dentária/terapia
8.
Oper Dent ; 46(4): 419-427, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624104

RESUMO

OBJECTIVES: To evaluate the influence of ferrule effect and mechanical fatigue aging on glass-fiber post push-out bond strength (PBS) to root-canal dentin at different root thirds of premolars. METHODS AND MATERIALS: Thirty-two sound maxillary premolar teeth were collected, and randomly assigned to two experimental groups (n=16): 'Remaining Dentin Ferrule' (RDF) = coronal crown cut 2.0 mm above the cementoenamel junction (CEJ); 'Without Dentin Ferrule' (WDF) = coronal crown cut at the cemento-enamel junction. Teeth were endodontically treated, post spaces were prepared up to 10.0-mm depth from CEJ, and glass-fiber posts were cemented using a dual-cure self-adhesive composite cement. Standardized cores were built using a light-cure composite, upon which tooth cores were prepared using a 1.5-mm taper ogival-end diamond bur. Crowns were handmade using self-cure acrylic resin and cemented using the aforementioned composite cement. Half of the specimens were subjected to 1,200,000 cycles of mechanical fatigue in a chewing simulator (F = 'Fatigue'), while the other half were stored in distilled water at 37°C for 1 week (C = 'Control'). All specimens were horizontally sectioned into 1.0-mm thick slices prior to PBS test; the failure modes were assessed using stereomicroscopy and scanning electron microscopy (SEM). Data were analyzed for each root third using two-way analysis of variance (ANOVA) followed by Tukey HSD post-hoc test; frequency distribution was compared by Chi-square test (α=0.05) and post-hoc comparisons with Bonferroni. RESULTS: The mean PBS in MPa (SD) were = RDF_F = 10.4 (2.9); WDF_F = 6.9 (1.7); RDF_C = 14.5 (2.7); WDF_C = 14.2 (2.9). Similar PBS were found for the root thirds. For all root thirds, significant differences were found for both the factors Dentin Ferrule and Fatigue, and their interaction (p<0.05). The lowest PBS was found for specimens without dentin ferrule subjected to chewing fatigue (p<0.001). Most failures occurred at the composite cement/dentin interface, followed by mixed and composite cement/glass-fiber post interfacial failures. There was a significant increase in mixed failures for the WDF_F group (p<0.001). CONCLUSION: Absence of 2.0-mm remaining dentin ferrule in premolars resulted in a higher decrease of the glass-fiber posts' PBS to dentin after mechanical fatigue, irrespective of root third.


Assuntos
Técnica para Retentor Intrarradicular , Resinas Compostas , Coroas , Materiais Dentários , Análise do Estresse Dentário , Dentina , Vidro , Mastigação , Teste de Materiais , Cimentos de Resina
9.
J Dairy Sci ; 104(12): 12567-12579, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34531050

RESUMO

Development and health during calfhood are paramount for the success of dairy operations because they are associated with longevity and productivity later in life. Thus, provision of nutritional supplements has been explored as an alternative to improve growth of preweaned calves. Holstein calves (female = 472, male = 46) from 2 dairies located in the San Joaquin Valley were assigned randomly to receive 25 g/d of Gammulin (APC Inc.) from 2 to 24 d of age (GAM = 263) or to receive no supplementation (control = 255). Calves were fed a mixture of waste milk and milk replacer (3.79 L/d), and study personnel added the supplement to the bottles of calves in the GAM treatment daily. Study personnel monitored calves 6 d/wk and recorded starter intake, fecal score (1 = firm, 4 = watery), and attitude score (1 = alert and responsive, 4 = recumbent). Blood samples were collected (4, 7, 14, 26, 44, 56, and 68 d of age) to determine concentrations of total protein, glucose (n = 64), nonesterified fatty acids (n = 64), ß-hydroxybutyrate (n = 171), and hematocrit (n = 518). Calves (n = 64) were treated with 0.5 mg of ovalbumin at 3, 21, and 42 d of age, and concentration of anti-ovalbumin IgG was measured. The percentage of polymorphonuclear leukocytes positive for phagocytosis and oxidative burst after the ex vivo exposure to an enteropathogenic Escherichia coli was evaluated (n = 64). We followed the female calves through the end of the first lactation or until they left the herd to evaluate the effect of treatment on first-lactation performance. Treatment did not affect metabolic and immune responses. During the supplementation (1 to 24 d of age), starter intake did not differ between treatments, but the GAM treatment reduced starter intake (638.5 ± 1.1 vs. 696.6 ± 1.1 g/d; mean ± standard error of the mean) from 25 to 60 d of age and average daily gain (798.8 ± 15.4 and 749.5 ± 15.2) from 23 to 60 d of age, resulting in reduced body weight at 60 d of age (68.4 ± 0.4 vs. 69.8 ± 0.5 kg). From 1 to 24 d of age, GAM treatment reduced the number of days calves had fecal score = 4 (ratio of number of days = 0.92; 95% confidence interval = 0.84-1.00) and it reduced the number of electrolyte treatments calves received (ratio of number of treatments = 0.92; 95% confidence interval = 0.85-0.99). Treatment did not affect the hazard of first calving and first-lactation 305-d milk yield, but the adjusted hazard ratio (0.82; 95% confidence interval = 0.65, 1.04) of pregnancy in the first lactation tended to be reduced for the GAM treatment. In the conditions of this experiment, supplementation with 25 g/d of GAM to the liquid feed from 2 to 24 d of age did not improve calfhood health and performance.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação , Masculino , Leite , Gravidez , Desmame
10.
J Mech Behav Biomed Mater ; 120: 104547, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33940486

RESUMO

This study aimed to analyze different methodologies (tensile, microtensile, shear, microshear, and interfacial toughness) for evaluation of the bond strength between zirconia (Y-TZP) and resin cement. Zirconia ceramic blocks (VITA in-Ceram® YZ, VITA Zahnfabrik, Germany) were obtained, substrate surfaces were air-abraded with aluminum oxide (50 µm) for 10 s (2 bar pressure, distance: 10 mm, angle: 90°). Then, the specimens were washed with distilled water, dried, and coated with Clearfil Ceramic Primer that was actively applied with a microbrush for 20 s. The specimens were then cemented with resin cement under a load of 750 g, followed by photo-polymerization (40 s on each surface). After cementation, the specimens were aged in thermocycling (8000 cycles, 5-55 °C, 30 s for each bath) and subjected to tensile, microtensile, shear, microshear or interfacial toughness tests. All specimens were inspected for failure modes. The microtensile test showed the highest bond value (18.29 N/mm2). The microshear tests showed the highest coefficient of variation (0.59) and highest number of pre-test failures. The interfacial energy to fracture test showed that as the shear stress increased its interaction in the adhesive interface, the coefficient of variation also increased. The bond strength of Y-TZP showed different results according to the methodology, as well as its interfacial energy to fracture varied according to the angulation/type of stress specimen was submitted. The lower the shear stress at the adhesive interface of the mixed tests (interfacial energy to fracture), the lower was the variability of the test.


Assuntos
Colagem Dentária , Cimentos de Resina , Óxido de Alumínio , Cerâmica , Análise do Estresse Dentário , Teste de Materiais , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
11.
Clin Transl Oncol ; 23(1): 5-9, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32447647

RESUMO

The COVID-19 pandemic caused a change in our society and put health systems in crisis worldwide. Different risk factors and comorbidities have been found that increase the risk of mortality when acquiring this infection. The use of alternative devices to the cigarette like the electronic cigarettes, the vapers have been studied widely and generators of great controversy since it has been discovered that they also produce different pulmonary affections. When developing the SARS-CoV2 infection, different theories have been generated about the greater predisposition to a worse prognosis of people who use electronic cigarettes; however, the information on this continues in discovery. A group of experts made up of oncologists, infectologists, pulmonologists, and epidemiologists met to review the literature and then generate theories about the impact of electronic cigarettes on SARS-CoV2 infection.


Assuntos
COVID-19/patologia , Sistemas Eletrônicos de Liberação de Nicotina , Vaping/efeitos adversos , COVID-19/epidemiologia , Suscetibilidade a Doenças , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Humanos , Macrófagos/metabolismo , Alvéolos Pulmonares/imunologia , Alvéolos Pulmonares/patologia , Risco , SARS-CoV-2 , Vaping/epidemiologia , Adulto Jovem
12.
Oper Dent ; 46(1): 63-74, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33351938

RESUMO

CLINICAL RELEVANCE: The use of multipeak LED light-curing guarantees efficiency on light activation of Ivocerin-containing light-cured resin cement.


Assuntos
Lâmpadas de Polimerização Dentária , Cimentos de Resina , Cura Luminosa de Adesivos Dentários , Teste de Materiais
13.
Clin Oncol (R Coll Radiol) ; 32(1): e19-e26, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31324474

RESUMO

AIMS: The workload pressure on medical oncologists will increase in the near future. There are no comprehensive data available about the current workload of medical oncologists in Europe. Here we report the European results of a global survey of the workload of medical oncologists. MATERIALS AND METHODS: An online survey was distributed through a snowball method via national oncology societies to chemotherapy-prescribing physicians in 21 European countries. We compared the workload of medical oncologists in Eastern European countries (EECs) and Western European countries (WECs). The primary measure of workload was the annual number of new cancer patient consults seen per oncologist. RESULTS: In total, 495 oncologists from 16 European countries completed our survey: 100 from seven EECs and 395 from nine WECs. The median number of annual consults per medical oncologist was 225 in EECs compared with 175 in WECs (P < 0.001). The proportion of medical oncologists seeing more than 300 consults/year was 35% (35/100) in EECs compared with 18% (68/395) in WECs. The median number of patients seen in a full day clinic was 25 in EECs and 15 in WECs (P < 0.001). Eastern European medical oncologists reported spending a median of 25 min per new consultation compared with 45 min in WECs (P < 0.001). The top two reported barriers in both EECs and WECs to patient care were high clinical volumes and insufficient time for reading. CONCLUSION: The clinical workload of medical oncologists in EECs was substantially higher than in WECs. European health policymakers and educators need to address existing disparities in the workload of medical oncologist, undertake plans for future workforce supply and consider alternative models of care.


Assuntos
Oncologia/métodos , Oncologistas/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
14.
Oper Dent ; 44(2): 210-218, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30106332

RESUMO

OBJECTIVE:: To compare the effect of hydrofluoric acid (HF) vs self-etching ceramic primer on resin cement microshear bond strength (µSBS) and ultramorphology of lithium disilicate (LD) ceramic. METHODS AND MATERIALS:: LD (IPS e.max CAD, Ivoclar Vivadent) blocks (14×4×2 mm3) were polished to 1200 grit and assigned to nine groups (n=5): CON: control, no LD surface treatment; IVO: 5.0% HF (IPS Ceramic Etching Gel, Ivoclar Vivadent); VIT: 5.0% HF (Vita Ceramics Etch, VITA Zahnfabrik); FGM: 5.0% HF (Condac Porcelana, FGM); ULT: 9.0% HF (Porcelain Etch, Ultradent); PRM: 9.6% HF (Premier Porcelain Etch Gel, Premier); BIS: 9.5% HF (Porcelain Etchant, Bisco Inc); DEN: 10.0% HF (Condicionador de Porcelanas, Dentsply Brazil); and MEP: self-etching ceramic primer (Monobond Etch & Prime, Ivoclar Vivadent). For all HF groups and control, an MDP-containing silane solution (MB+, Monobond Plus, Ivoclar Vivadent) was applied on rinsing the HF gel and air drying. Three transparent matrices for each specimen were filled with light-cured resin cement (Variolink Veneer, Ivoclar Vivadent). After storage in water for 48 hours at 37°C, specimens were tested in shear mode to measure µSBS. Mode of failure was analyzed at 50×. Statistical analysis included one-way analysis of variance and the Duncan post hoc test (α=0.05). Thirty-six additional LD specimens were assigned to the same experimental groups (n=4) and observed under a field-emission scanning electron microscope (FESEM) at magnifications ranging from 10,000× to 100,000×. RESULTS:: IVO resulted in statistically higher mean µSBS than all the other groups. MEP resulted in statistically lower µSBS than all HF groups. The failure mode for MEP was predominantly adhesive. The most frequent failure mode for the HF groups was mixed. CON resulted in 100% pretesting failures. For FESEM, no retentive pattern was observed for CON specimens. MEP resulted in the least pronounced etching pattern, few areas around crystals exhibited a slight increase in retention pattern compared to the control group. All HF gels created microporosities on the LD surface with distinct etching patterns. VIT and DEN resulted in an LD ultramorphology that suggested overetching. CONCLUSIONS:: HF etching followed by a silane solution resulted in higher bond strengths than a self-etching ceramic primer. Some HF gels may cause overetching of the LD intaglio surface.


Assuntos
Colagem Dentária , Porcelana Dentária , Brasil , Cerâmica , Ácido Fluorídrico , Teste de Materiais , Cimentos de Resina , Silanos , Propriedades de Superfície
16.
Poult Sci ; 98(2): 932-939, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137619

RESUMO

Campylobacter is regarded as the most common bacterial cause of gastroenteritis throughout the world and most cases of human campylobacteriosis can be traced back to the consumption of poultry meat. In Brazil, few studies evaluated the genetic relatedness among Campylobacter isolates. The aim of this research was to evaluate the genetic diversity of Campylobacter spp. isolated from poultry meat products sold on the retail market in Southern Brazil. The presumptive identification of Campylobacter was performed using traditional microbiological analysis, followed by molecular confirmation by PCR. The genetic diversity of isolates was analyzed by pulsed-field gel electrophoresis (PFGE). Campylobacter spp. was isolated from 91.7% (33/36) of the samples, totaling 48 isolates. Campylobacter jejuni was the most prevalent species isolated (90.8%). PFGE data revealed 26 pulsotypes and 18 PFGE patterns composed of only 1 isolate. Campylobacter isolates exhibited high genetic diversity; however, some clones were recurrent in the poultry meat products sold on the retail market. As the south region of Brazil is an important producer and exporter of chicken meat, our results highlight the need to control this pathogen in the food chain in this area of the world to reduce the risks of exposing consumers to campylobacteriosis.


Assuntos
Campylobacter coli/genética , Campylobacter jejuni/genética , Microbiologia de Alimentos , Variação Genética , Produtos Avícolas/microbiologia , Animais , Brasil , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Galinhas , Eletroforese em Gel de Campo Pulsado/veterinária , Reação em Cadeia da Polimerase/veterinária
17.
Dent Mater ; 34(11): 1679-1689, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30293689

RESUMO

OBJECTIVES: Dentin biomodification using collagen cross-linkers has been proposed as one of the strategies to improve bond durability of adhesives to dentin. However, literature is not very consistent regarding their benefit, in particular when cross-linkers are applied in clinically realistic application times. This study investigated the effect of three cross-linkers on the mini-interfacial fracture toughness (mini-iFT) of four adhesives bonded to dentin following either etch&rinse (E&R) or self-etch (SE) modes. METHODS: 60 molars were randomly divided in accordance with the three variables: cross-linker, adhesive and bonding mode (n=5). The cross-linkers glutaraldehyde (5wt%; GA), proanthocyanidin (6.5wt%; PA), or UVA-activated riboflavin (0.5wt%; RB), and distilled water (control) were applied on dentin for 60s after acid-etching (E&R) or before self-etching (SE). The 3-step E&R adhesive (3E&Ra) OptiBond FL (Kerr), the 2-step SE adhesive (2SEa) Clearfil SE Bond 2 (Kuraray Noritake) and the universal adhesives G-Premio Bond (GC) and Prime&Bond Active (Dentsply), the latter two employed in both E&R and SE modes, were applied following the respective manufacturer's instructions. Composite buildups (8×8×8mm) were made using Filtek Supreme XTE (3M) prior to 1-week storage in artificial saliva. After the teeth were sectioned into mini-specimens (1.5×2.0×18mm), a single notch was prepared at the adhesive-dentin interface. Half of the specimens were immediately loaded until failure by 4-point bending to determine the mini-iFT, while the remaining specimen set was tested upon 6-month aging. Data were statistically analyzed with a linear model (p<0.05). RESULTS: No significant decrease in mini-iFT was noted only for PA (p<0.05), while the mini-iFT decreased for both other cross-linkers and in quite a similar way as when solely water (Wa) was applied. SIGNIFICANCE: The cross-linker proanthocyanidin (PA) applied in clinically relevant conditions was able to maintain a stable mini-iFT after 6-month aging. The incorporation of UVA-activated riboflavin (RB) and glutaraldehyde (GA) in the dentin-bonding protocol appeared not effective to improve the stability of adhesive-dentin interfaces.


Assuntos
Reagentes de Ligações Cruzadas/química , Colagem Dentária/métodos , Adesivos Dentinários/química , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Glutaral/química , Humanos , Técnicas In Vitro , Teste de Materiais , Metacrilatos , Dente Molar , Ácidos Polimetacrílicos , Proantocianidinas/química , Distribuição Aleatória , Cimentos de Resina , Riboflavina/química , Propriedades de Superfície
18.
Curr Oncol ; 25(3): 206-212, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29962838

RESUMO

Background: In 2000, a Canadian task force recommended that medical oncologists (mos) meet a target of 160-175 new patient consultations per year. Here, we report the Canadian results of a global survey of mo workload compared with mo workload in other high-income countries (hics). Methods: Using a snowball method, an online survey was distributed by national oncology societies to chemotherapy-prescribing physicians in 22 hics (World Bank criteria). The survey was distributed within Canada to all members of the Canadian Association of Medical Oncologists. Workload was measured as the annual number of new cancer patient consults per oncologist. Results: The survey was completed by 782 oncologists from hics, including 58 from Canada. Median annual consults per mo were 175 in Canada compared with 125 in other hics. The proportions of mos having 100 or fewer consults or more than 300 consults per year were 3% (2/58) and 5% (3/58) in Canada compared with 31% (222/724) and 16% (116/724) in other hics (p < 0.001 and p = 0.023 respectively). The median number of patients seen in a full-day clinic was 15 in Canada and 25 in other hics (p = 0.220). Canadian mos reported spending a median of 55 minutes per new consultation; new consultations of 35 minutes were reported in other hics (p < 0.001). Median hours worked per week was 55 in Canada and 45 in other hics (p = 0.200). Conclusions: Although the median annual clinical volume for Canadian mos aligns with recommended targets, half the respondents exceeded that level of activity. Health policymakers and educators have to consider mo workforce supply and alternative models of care in preparation for the anticipated surge in cancer incidence in the coming decade.


Assuntos
Pesquisas sobre Atenção à Saúde/métodos , Oncologia/normas , Carga de Trabalho/estatística & dados numéricos , Canadá , Feminino , Humanos , Masculino , Inquéritos e Questionários
19.
Braz J Med Biol Res ; 51(3): e7214, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29340530

RESUMO

A biosimilar is a biologic product that is similar to a reference biopharmaceutical product, the manufacturing process of which hinders the ability to identically replicate the structure of the original product, and therefore, it cannot be described as an absolute equivalent of the original medication. The currently available technology does not allow for an accurate copy of complex molecules, but it does allow the replication of similar molecules with the same activity. As biosimilars are about to be introduced in oncology practice, these must be evaluated through evidence-based medicine. This manuscript is a position paper, where the Brazilian Society of Clinical Oncology (SBOC) aims to describe pertinent issues regarding the approval and use of biosimilars in oncology. As a working group on behalf of SBOC, we discuss aspects related to definition, labeling/nomenclature, extrapolation, interchangeability, switching, automatic substitution, clinical standards on safety and efficacy, and the potential impact on financial burden in healthcare. We take a stand in favor of the introduction of biosimilars, as they offer a viable, safe, and cost-effective alternative to the biopharmaceutical products currently used in cancer. We hope this document can provide valuable information to support therapeutic decisions that maximize the clinical benefit for the thousands of cancer patients in Brazil and can contribute to expedite the introduction of this new drug class in clinical practice. We expect the conveyed information to serve as a basis for further discussion in Latin America, this being the first position paper issued by a Latin American Oncology Society.


Assuntos
Medicamentos Biossimilares/uso terapêutico , Oncologia , Neoplasias/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Medicamentos Biossimilares/economia , Medicamentos Biossimilares/normas , Brasil , Ensaios Clínicos como Assunto , Medicina Baseada em Evidências , Humanos , Neoplasias/imunologia , Farmacovigilância , Sociedades Médicas
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