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Lufenuron, a molecule that belongs to the chitin synthesis inhibitors group of insect growth regulators, has a still unclear mode of action, but probably it affects chitin synthesis at a post‐transcriptional level. In this work, we report the effects of lufenuron on nutrition and reproduction in adult females of Anthonomus grandis, the main neotropical cotton pest and tried to link the effects on peritrophic matrix (PM) with egg viability. After Lufenuron treatment A. grandis females presented weight loss and less accumulation of protein and lipids probably due to PM breakdown. Also, treated females produce the same quantity of eggs as the control, although eggs from lufenuron‐treated females were less viable. After morphological and histochemical analysis, we have noticed that oocytes from lufenuron‐treated females contained less protein. Finally, lufenuron‐treated females produced at least nine times less vitellogenin (AgraVg) RNA than control females. We specifically showed that lufenuron treatment caused PM disruption and it has probably led to vitellogenin (AgraVg) downregulation in females culminating in egg unviability. The effect of lufenuron on PM leads to insect malnutrition, and this malnutrition downregulates vitellogenin among other genes. This is the first work that describes and tries to correlate the lufenuron effects on adult females. [ABSTRACT FROM AUTHOR]

Aim: The purpose was to compare the fracture strength between restorations containing the metal pin (MP) and those containing the glass fiber pin (GFP)., Materials and Methods: Forty-five healthy bovine anterior teeth were used in this study. A preparation of 4 mm × 4 mm was created on the incisal surface of each tooth. All teeth were prepared in the same way. The teeth were randomly divided into three groups (n = 15): group I-control: teeth restored with resin composite (RC) only, without reinforcement; group II-Each tooth was restored with a MP and RC; group III-Each tooth was restored with a GFP and RC. The specimens were left in an oven at a temperature of 37°C for 24 hours before performing the fracture strength tests. The fracture strength test was performed in a universal test machine at an angle of 90°., Results: The Tukey test (p ≤ 0.05) showed that for the variable maximum force (kgf), there was no statistically significant difference among the groups (p = 0.272). The chi-square test showed that groups II and III presented over 70% of cohesive-adhesive type fractures when compared with group I (over 70% of adhesive fractures), and this difference was statistically significant (p < 0.05)., Conclusion: The pins tested did not increase the fracture resistance of the restorations (RC) in comparison with group I (without reinforcement); however, with the use of the MP and GFP, there was a predominance of cohesive-adhesive fractures (groups II and III)., Clinical Significance: Evaluate if the new GFP can generate greater resistance to fracture of RC restorations.