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The olive fruit fly, Bactrocera oleae, causes great damage to the quality and quantity of olive production worldwide. Pest management approaches have proved difficult for a variety of reasons, a fact that has brought about a need for alternative tools and approaches. Here we report for the first time in B. oleae the development of the clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) gene editing tool, using the well‐known eye colour marker gene scarlet. Two synthetic guide RNAs targeting the coding region of the scarlet gene were synthesized and shown to work efficiently in vitro. These reagents were then microinjected along with purified Cas9 protein into early‐stage embryos. Successful CRISPR‐induced mutations of both copies of the scarlet gene showed a striking yellow eye phenotype, indicative of gene disruption. Multiple successful CRISPR events were confirmed by PCR and sequencing. The establishment of an efficient CRISPR‐based gene editing tool in B. oleae will enable the study of critical molecular mechanisms in olive fruit fly biology and physiology, including the analysis of insecticide resistance mechanisms and the discovery of novel insecticide targets, as well as facilitate the development of novel biotechnology‐based pest control strategies. [ABSTRACT FROM AUTHOR]

Root fractures are relatively uncommon among other dental traumas and mostly affect the anterior dentition. This case report presents the endodontic and prosthodontic management of a maxillary central incisor with a combined fracture in the middle third of the root and the crown, as well as the 7-year follow up of the case. The healing potential of a horizontal root fracture in the middle third of the root is highlighted when appropriate treatment is applied. MTA used for obturation of the coronal fragment, induced hard tissue formation apically and promoted healing in the area, while the 2mm MTA left as apical barrier at the second stage of re-treatment and obturation with gutta-percha prevented its extrusion. The multidisciplinary approach in the management of such cases ensures a long term survival.

Purpose: The aim of this paper is to document the oral hygiene and nutrition habits of young people (aged 18 to 25) in Greece.

In view of the ongoing climate change and the ever-growing world population, novel agricultural solutions are required to ensure sustainable food supply. Microbials, natural substances, semiochemicals and double stranded RNAs (dsRNAs) are all considered potential low risk pesticides. DsRNAs function at the molecular level, targeting specific regions of specific genes of specific organisms, provided that they share a minimal sequence complementarity of approximately 20 nucleotides. Thus, dsRNAs may offer a great alternative to conventional chemicals in environmentally friendly pest control strategies. Any low-risk pesticide needs to be efficient and exhibit low toxicological potential and low environmental persistence. Having said that, in the current review, the mode of dsRNA action is explored and the parameters that need to be taken into consideration for the development of efficient dsRNA-based pesticides are highlighted. Moreover, since dsRNAs mode of action differs from those of synthetic pesticides, custom-made risk assessment schemes may be required and thus, critical issues related to the risk assessment of dsRNA pesticides are discussed here., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Resistance to pyrethroid insecticides has evolved in Bactrocera oleae populations in Greece, threatening the efficacy of control interventions based on this insecticide class. Here we report the collection of populations from Crete, with resistance levels reaching up to 132-folds, compared to susceptible laboratory strains and show that pyrethroid resistance is substantially suppressed by the PBO synergist, suggesting the involvement of detoxification enzymes. To identify specific candidate genes implicated in resistance, we performed comparative transcriptomic analysis, between the pyrethroid resistant populations from Crete and the susceptible laboratory strains, using both whole bodies and Malpighian tubules. Several genes were found differentially transcribed between resistant and susceptible flies in each comparison, with P450s being among the most highly over-expressed detoxification genes in pyrethroid resistant populations. Four of the over-expressed P450s (Cyp6A61, Cyp6G6, Cyp4P6 and Cyp6G28) were recombinantly expressed in Escherichia coli and in vitro metabolism assays revealed that CYP6A61 is capable of metabolizing alpha-cypermethrin, while CYP6G6, CYP4P6 and CYP6G28 are capable of metabolizing deltamethrin. No metabolism of neonicotinoid insecticides was recorded. We further silenced CYP6G6 in vivo, via RNAi, which led to a small, but significant increase in deltamethrin toxicity. The study provides valuable information towards the development of molecular diagnostics and evidence-based insecticide resistance management strategies., Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The olive fruit fly, Bactrocera oleae, the most serious pest of olives, requires the endosymbiotic bacterium Candidatus Erwinia dacicola in order to complete its development in unripe green olives. Hence, a better understanding of the symbiosis of Ca. E. dacicola and its insect host may lead to new strategies for B. oleae control. The relative abundance of bacteria during the fly life cycle comparing black and green olives was estimated by real time quantitative PCR revealing significant fluctuations during development in black olives with a peak of the bacteria in the second instar larvae. By microscopy analysis of larvae, we show that the bacteria reside extracellularly in the gastric caeca. During the transition to late third instar larvae, the bacteria were discharged into the midgut concomitant with a change in caeca size and morphology due to the contraction of the muscles surrounding the caeca. A similar alteration was also observed in a laboratory strain devoid of bacteria. To further investigate the symbiotic interaction and the change in caeca morphology a comparative transcriptomics analysis was undertaken. Samples of dissected caeca from second and third instar larvae collected from the field as well as second instar larvae from a laboratory strain devoid of symbionts showed significant changes in transcript expression. This highlighted genes associated with the developmental changes revealed by the microscopic analysis as well as responses to microorganisms., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Pesticides remain one of the most effective ways of controlling agricultural and public health insects, but much is still unknown regarding how these compounds reach their targets. Specifically, the role of ABC transporters in pesticide absorption and excretion is poorly understood, especially compared to the detailed knowledge about mammalian systems. Here, we present a comprehensive characterization of pesticide transporters in the model insect Drosophila melanogaster . An RNAi screen was performed, which knocked down individual ABCs in specific epithelial tissues and examined the subsequent changes in sensitivity to the pesticides spinosad and fipronil. This implicated a novel ABC drug transporter, CG4562, in spinosad transport, but also highlighted the P-glycoprotein orthologue Mdr65 as the most impactful ABC in terms of chemoprotection. Further characterization of the P-glycoprotein family was performed via transgenic overexpression and immunolocalization, finding that Mdr49 and Mdr50 play enigmatic roles in pesticide toxicology perhaps determined by their different subcellular localizations within the midgut. Lastly, transgenic Drosophila lines expressing P-glycoprotein from the major malaria vector Anopheles gambiae were used to establish a system for in vivo characterization of this transporter in non-model insects. This study provides the basis for establishing Drosophila as a model for toxicology research on drug transporters.

Naphthodianthrones such as fagopyrin and hypericin found mainly in buckwheat ( Fagopyrum spp.) and St. John's wort (SJW) ( Hypericum perforatum L.) are natural photosensitizers inside the cell. The effect of photosensitizers was studied under dark conditions on growth, morphogenesis and induction of death in Saccharomyces cerevisiae . Fagopyrin and hypericin induced a biphasic and triphasic dose response in cellular growth, respectively, over a 10-fold concentration change. In fagopyrin-treated cells, disruptions in the normal cell cycle progression were evident by microscopy. DAPI staining revealed several cells that underwent premature mitosis without budding, a striking morphological abnormality. Flow Cytometric (FC) analysis using a concentration of 100 µM showed reduced cell viability by 41% in fagopyrin-treated cells and by 15% in hypericin-treated cells. FC revealed the development of a secondary population of G1 cells in photosensitizer-treated cultures characterized by small size and dense structures. Further, we show that fagopyrin and the closely related hypericin altered the shape and the associated fluorescence of biofilm-like structures. Colonies grown on solid medium containing photosensitizer had restricted growth, while cell-to-cell adherence within the colony was also affected. In conclusion, the photosensitizers under dark conditions affected culture growth, caused toxicity, and disrupted multicellular growth, albeit with different efficiencies.

The olive fruit fly, Bactrocera oleae, the most serious pest of olives, requires the endosymbiotic bacteria Candidatus Erwinia dacicola in order to complete its development in unripe green olives. Hence a better understanding of the symbiosis of Ca. E. dacicola and its insect host may lead to new strategies for reduction of B. oleae and thus minimize its economic impact on olive production. Studies of this symbiosis are hampered as the bacterium cannot be grown in vitro and the established B. oleae laboratory populations, raised on artificial diets, are devoid of this bacterium. Here, we sought to develop a method to transfer the bacteria from wild samples to laboratory populations. We tested several strategies. Cohabitation of flies from the field with the laboratory line did not result in a stable transfer of bacteria. We provided the bacteria directly to the egg and also in the food of the larvae but neither approach was successful. However, a robust method for transfer of Ca. E. dacicola from wild larvae or adults to uninfected flies by transplantation to females was established. Single female lines were set up and the bacteria were successfully transmitted for at least three generations. These results open up the possibilities to study the interaction between the symbiont and the host under controlled conditions, in view of both understanding the molecular underpinnings of an exciting, unique in nature symbiotic relationship, as well as developing novel, innovative control approaches.

Malaria incidence has halved since the year 2000, with 80% of the reduction attributable to the use of insecticides. However, insecticide resistance is now widespread, is rapidly increasing in spectrum and intensity across Africa, and may be contributing to the increase of malaria incidence in 2018. The role of detoxification enzymes and target site mutations has been documented in the major malaria vector Anopheles gambiae; however, the emergence of striking resistant phenotypes suggests the occurrence of additional mechanisms. By comparing legs, the most relevant insect tissue for insecticide uptake, we show that resistant mosquitoes largely remodel their leg cuticles via enhanced deposition of cuticular proteins and chitin, corroborating a leg-thickening phenotype. Moreover, we show that resistant female mosquitoes seal their leg cuticles with higher total and different relative amounts of cuticular hydrocarbons, compared with susceptible ones. The structural and functional alterations in Anopheles female mosquito legs are associated with a reduced uptake of insecticides, substantially contributing to the resistance phenotype.

Background: The aim of this review is to systematically investigate the effect of a susceptible genotype to periodontitis with the clinical outcomes of periodontal regeneration., Material and Methods: Based on a focused question, an electronic search identified 155 unique citations. Three journals (Journal of Periodontology, Journal of Clinical Periodontology and Journal of Periodontal Research), references of relevant studies and review articles were hand-searched. Two independent reviewers implementing eligibility inclusion criteria selected the studies., Results: Of the 155, four studies fulfilled the inclusion criteria. All studies were published between 2000 and 2004 and the samples' size was 40 to 86 patients. Polymorphisms of Interleukin-1 (IL-1) gene were included in all. Three out of four studies failed to identify an association between susceptible genotypes to periodontitis and clinical outcomes of periodontal regeneration, while one found an association. The heterogeneity and small number of studies included prevented the conduct of a meta-analysis. No studies were identified evaluating the effect of other genotypes and as a result only IL-1 genotype studies were included., Conclusions: Within the limits of the present review, no direct conclusion for the effect of a susceptible IL-1 genotype status to the clinical outcome after periodontal regeneration could be drawn. The need of more qualitative studies to explore a possible association emerges.