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The pretreatment of dentin with cross-linking agents during bonding procedures has been proposed to improve the mechanical properties of the collagen in the hybrid layer and reduce the biodegradation of the adhesive interface. The aim of this study was to evaluate the influence of pretreatment with two carbodiimides on the dentin bond strength of universal adhesives, after thermocycling. Three universal adhesives in the self-etching mode were used (Single Bond Universal-SBU, Clearfil Universal-CLU and Ambar Universal-ABU). A self-etching adhesive system (Clearfil SE Bond-CSB) was used as control. Two carbodiimides, 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide (EDC) and N,N'-dicyclohexylcarbodiimide (DCC), were applied for 1 min. The excess solution was removed with absorbent paper and the universal adhesives were applied. The specimens were stored for 24 h in distilled water at 37 °C or 10,000 thermal cycles (5-55 °C, 30 s) and then were prepared for microtensile bond strength test (n = 4 teeth, average of 21 sticks per group). Data were analyzed using three-way ANOVA and Tukey's (α = 5%). After 24 h, SBU and CSB had statistically similar bond strength values for the control groups (22.07 ± 9.03 and 19.82 ± 7.28 MPa), with EDC (30.21 ± 11.30 and 19.67 ± 5.36 MPa) and DCC (30.12 ± 13.43 and 19.82 ± 7.28 MPa) pretreatments (p > 0.05). The use of EDC (32.57 ± 9.60 MPa) and DCC (24.71 ± 9.87 MPa) showed statistically higher bond strength for CLU than for the control group (14.62 ± 6.16 MPa; p < 0.05). After thermocycling, the SBU, CLU, and CSB groups showed statistically similar bond strengths with the use of EDC (27.08 ± 8.44; 18.74 ± 5.41; and 24.55 ± 10.43 MPa) and without the use of cross linkers (20.06 ± 7.99; 22.55 ± 9.04; and 26.54 ± 10.13 MPa; p > 0.05). Groups tested after 24 h in distilled water presented higher bond strength than those submitted to thermocycling. It can be concluded that the use of cross linkers influenced the immediate bond strength of the universal adhesives, and this was dependent on the combination of the adhesive system and type of carbodiimide. The use of EDC increased the immediate bond strength of CLU. DCC increased the bond strength of ABU at 24 h, but the values were lower than those of the control group after aging for three out of the four adhesives.

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Early diagnosis of COVID-19 in suspected patients is essential for contagion control and damage reduction strategies. We investigated the applicability of attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy associated with machine learning in oropharyngeal swab suspension fluid to predict COVID-19 positive samples. The study included samples of 243 patients from two Brazilian States. Samples were transported by using different viral transport mediums (liquid 1 or 2). Clinical COVID-19 diagnosis was performed by the RT-PCR. We built a classification model based on partial least squares (PLS) associated with cosine k-nearest neighbours (KNN). Our analysis led to 84% and 87% sensitivity, 66% and 64% specificity, and 76.9% and 78.4% accuracy for samples of liquids 1 and 2, respectively. Based on this proof-of-concept study, we believe this method could offer a simple, label-free, cost-effective solution for high-throughput screening of suspect patients for COVID-19 in health care centres and emergency departments.

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As micotoxinas, metabólitos secundários tóxicos produzidos por espécies de fungos filamentosos, podem contaminar uma ampla gama de alimentos, dentre eles, a ração canina. A ingestão de alimentos contaminados por micotoxinas, causa as micotoxicoses, doenças que possuem uma variedade de sinais clínicos dependentes da quantidade de toxina ingerida, tempo de exposição, bem como das características ligadas a cada tipo de micotoxina. O presente trabalho revisa os aspectos relevantes relacionados às micotoxinas quanto a sua origem e conceito, fatores que favorecem a sua produção, alimentos mais acometidos, além dos principais sinais clínicos observados, tratamento, controle e prevenção na espécie canina.

Mycotoxins, toxic secondary metabolites produced by filamentous fungus species, can contaminate a wide range of nourishments, as dog food. The ingestion of a diet contaminated with micotoxins causes mycotoxicosis, diseases which present a variety of clinical signs dependent on the amount of toxin ingested, time of exposure, as well as characteristics related to each type of mycotoxin. The present paper performs a review of major aspects related to mycotoxins about their origin and concept, factors that favor their production, most affected foods, main clinical signs observed in dogs, treatment, control, and prevention.

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RESUMO

As micotoxinas, metabólitos secundários tóxicos produzidos por espécies de fungos filamentosos, podem contaminar uma ampla gama de alimentos, dentre eles, a ração canina. A ingestão de alimentos contaminados por micotoxinas, causa as micotoxicoses, doenças que possuem uma variedade de sinais clínicos dependentes da quantidade de toxina ingerida, tempo de exposição, bem como das características ligadas a cada tipo de micotoxina. O presente trabalho revisa os aspectos relevantes relacionados às micotoxinas quanto a sua origem e conceito, fatores que favorecem a sua produção, alimentos mais acometidos, além dos principais sinais clínicos observados, tratamento, controle e prevenção na espécie canina.(AU)

Mycotoxins, toxic secondary metabolites produced by filamentous fungus species, can contaminate a wide range of nourishments, as dog food. The ingestion of a diet contaminated with micotoxins causes mycotoxicosis, diseases which present a variety of clinical signs dependent on the amount of toxin ingested, time of exposure, as well as characteristics related to each type of mycotoxin. The present paper performs a review of major aspects related to mycotoxins about their origin and concept, factors that favor their production, most affected foods, main clinical signs observed in dogs, treatment, control, and prevention.(AU)

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Introduction: Periodontal scaling is the treatment approach most used to remove dental calculus, plaque, and altered cementum from root surface. During root decontamination, the instruments used leave the root rougher and more irregular. Objective: To verify the root surface after mechanical scaling with different Gracey curettes steel through SEM and superficial roughness analyses. Material and methods: Twelve teeth were embedded in acrylic resin. The teeth were instrumented with new Gracey curettes Gracey 5/6 from different brands. The groups (n=2) were divided into: control, no instrumentation (GC); carbon steel (CSN); stainless steel Neumar (SSN); stainless steel Millenium (SSM); premium steel Neumar (PSN); Hu-Friedy (HF). An area measuring 3 x 3 mm2 was marked on the distal surface of the root to guide the Reading of the root topography on SEM and rugosimeter. The data were analyzed by a single examiner previously calibrated. SEM analysis was based on scores of the root surface smoothness after scaling. We analyzed the parameters of mean roughness (Ra) and mean roughness deepness (Rz). SEM data were submitted to statistical analysis through Fisher's exact test (p < 0.002) and roughness data by Anova followed by Student t test. Results: The quality of the active surface of the curette demonstrated by SEM and roughness analyses that it can exert difference in the result regarding to the homogeneity produced after the scaling of root surface. Group SSM demonstrated a homogenous root surface (score 0) in SEM and better smoothness in rugosimeter analysis. Conclusion: According to com the methodology used, the group of curettes that provided better smoothness of root surface after scaling was SSM.