The Study of Cell-Penetrating Peptides to Deliver dsRNA and siRNA by Feeding in the Desert Locust, Schistocerca gregaria.

RNA(i) interference is a gene silencing mechanism triggered by double-stranded (ds)RNA, which promises to contribute to species-specific insect pest control strategies. The first step toward the application of RNAi as an insecticide is to enable efficient gene silencing upon dsRNA oral delivery. The desert locust, Schistocerca gregaria is a devastating agricultural pest. While this species is responsive to dsRNA delivered by intra-hemocoelic injection, it is refractory to orally delivered dsRNA. In this study, we evaluated the capacity of five cell-penetrating peptides (CPPs) to bind long dsRNA and protect it from the locust midgut environment. We then selected the CPP EB1 for further in vivo studies. EB1:dsRNA complexes failed to induce RNAi by feeding. Interestingly, we observed that intra-hemocoelic injection of small-interfering (si)RNAs does not result in a silencing response, but that this response can be obtained by injecting EB1:siRNA complexes. EB1 also protected siRNAs from midgut degradation activity. However, EB1:siRNA complexes failed as well in triggering RNAi when fed. Our findings highlight the complexity of the dsRNA/siRNA-triggered RNAi in this species and emphasize the multifactorial nature of the RNAi response in insects. Our study also stresses the importance of in vivo studies when it comes to dsRNA/siRNA delivery systems.

Identification and Profiling of a Novel Bombyx mori latent virus Variant Acutely Infecting Helicoverpa armigera and Trichoplusia ni.

Insect cell expression systems are increasingly being used in the medical industry to develop vaccines against diseases such as COVID-19. However, viral infections are common in these systems, making it necessary to thoroughly characterize the viruses present. One such virus is Bombyx mori latent virus (BmLV), which is known to be specific to Bombyx mori and to have low pathogenicity. However, there has been little research on the tropism and virulence of BmLV. In this study, we examined the genomic diversity of BmLV and identified a variant that persistently infects Trichoplusia ni-derived High Five cells. We also assessed the pathogenicity of this variant and its effects on host responses using both in vivo and in vitro systems. Our results showed that this BmLV variant causes acute infections with strong cytopathic effects in both systems. Furthermore, we characterized the RNAi-based immune response in the T. ni cell line and in Helicoverpa armigera animals by assessing the regulation of RNAi-related genes and profiling the generated viral small RNAs. Overall, our findings shed light on the prevalence and infectious properties of BmLV. We also discuss the potential impact of virus genomic diversity on experimental outcomes, which can help interpret past and future research results.

What Are the Functional Roles of Piwi Proteins and piRNAs in Insects?

Research on Piwi proteins and piRNAs in insects has focused on three experimental models: oogenesis and spermatogenesis in Drosophila melanogaster, the antiviral response in Aedes mosquitoes and the molecular analysis of primary and secondary piRNA biogenesis in Bombyx mori-derived BmN4 cells. Significant unique and complementary information has been acquired and has led to a greater appreciation of the complexity of piRNA biogenesis and Piwi protein function. Studies performed in other insect species are emerging and promise to add to the current state of the art on the roles of piRNAs and Piwi proteins. Although the primary role of the piRNA pathway is genome defense against transposons, particularly in the germline, recent findings also indicate an expansion of its functions. In this review, an extensive overview is presented of the knowledge of the piRNA pathway that so far has accumulated in insects. Following a presentation of the three major models, data from other insects were also discussed. Finally, the mechanisms for the expansion of the function of the piRNA pathway from transposon control to gene regulation were considered.

Baricitinib or imatinib in hospitalized COVID-19 patients: Results from COVINIB, an exploratory randomized clinical trial.

Baricitinib and imatinib are considered therapies for coronavirus disease 2019 (COVID-19), but their ultimate clinical impact remains to be elucidated, so our objective is to determine whether these kinase inhibitors provide benefit when added to standard care in hospitalized COVID-19 patients. Phase-2, open-label, randomized trial with a pick-the-winner design conducted from September 2020 to June 2021 in a single Spanish center. Hospitalized adults with COVID-19 pneumonia and a symptom duration ≤10 days were assigned to 3 arms: imatinib (400 mg qd, 7 days) plus standard-care, baricitinib (4 mg qd, 7 days) plus standard-care, or standard-care alone. Primary outcome was time to clinical improvement (discharge alive or a reduction of 2 points in an ordinal scale of clinical status) compared on a day-by-day basis to identify differences ≥15% between the most and least favorable groups. Secondary outcomes included oxygenation and ventilatory support requirements, additional therapies administered, all-cause mortality, and safety. One hundred and sixty-five patients analyzed. Predefined criteria for selection of the most advantageous arm were met for baricitinib, but not for imatinib. However, no statistically significant differences were observed in formal analysis, but a trend toward better results in patients receiving baricitinib was found compared to standard care alone (hazard ratio [HR] for clinical improvement: 1.41, 95% confidence intervals [CI]: 0.96-2.06; HR for discontinuing oxygen: 1.46, 95% CI: 0.94-2.28). No differences were found regarding additional therapies administered or safety. Baricitinib plus standard care showed better results for hospitalized COVID-19 patients, being the most advantageous therapeutic strategy among those proposed in this exploratory clinical trial.

Medição da temperatura corporal em crianças: Estudo comparativo entre o método de medição axilar e timpânico / Child body thermometry: A comparative study of axillary and tympanic thermometry / Medición de la temperatura corporal en niños: Estudio comparativo entre el método de medición axilar y timpânico

Resumo Enquadramento: A temperatura corporal é um dos sinais vitais mais avaliados nos cuidados de saúde pediátricos para avaliação e orientação clínica. Objetivos: Avaliar a concordância entre a medição da temperatura por via axilar e timpânica em crianças dos 6 aos 36 meses. Metodologia: Estudo observacional e descritivo desenvolvido num hospital de nível II, em Portugal. O protocolo de medição da temperatura seguiu as orientações da Direção-Geral da Saúde. Resultados: Participaram no estudo 331 crianças. A diferença entre a temperatura timpânica e axilar variou entre os 0,00ºC e os 1,40ºC com uma média de 0,45ºC ± 0,30ºC e uma mediana de 0,50ºC, com uma concordância quase perfeita entre os dois métodos. Observou-se um efeito no valor da temperatura consoante o método utilizado em todas as variáveis estudadas. Conclusão: Existe uma concordância quase perfeita entre estes dois métodos de medição da temperatura, não influenciando a tomada de decisão clínica. Dado a maior facilidade de implementação e exequibilidade, as vantagens do método de avaliação via timpânica são superiores ao método tradicional via axilar, pelo que poderá ser implementado como rotina na avaliação da temperatura em crianças dos 6 aos 36 meses.

Abstract Background: Body temperature is one of the most evaluated vital signs in pediatric health care for clinical assessment and guidance. Objectives: To evaluate the agreement between axillary and tympanic thermometry in children aged 6 to 36 months. Methodology: An observational and descriptive study was carried out in a level II hospital in Portugal. The thermometry protocol followed the guidelines of the Portuguese Directorate-General of Health. Results: A total of 331 children participated in the study. The difference between tympanic and axillary temperatures ranged from 0.00ºC to 1.40ºC, with a mean of 0.45ºC ± 0.30ºC and a median of 0.50ºC, an almost perfect agreement between both methods. An effect on the temperature value was observed according to the technique used in all variables studied. Conclusion: There is an almost perfect agreement between these two thermometry methods, not influencing clinical decision-making. Advantages of the tympanic method over the traditional axillary method include easy implementation and feasibility. Therefore, it can be routinely implemented in assessing temperature in children aged 6 to 36 months.

Resumen Marco contextual: La temperatura corporal es una de las constantes vitales más valoradas en los cuidados de salud pediátricos para la evaluación y orientación clínica. Objetivos: Evaluar la concordancia entre la medición de la temperatura axilar y la timpánica en niños de 6 a 36 meses. Metodología: Estudio observacional y descriptivo desarrollado en un hospital de nivel II de Portugal. El protocolo de medición de la temperatura siguió las directrices de la Dirección General de Sanidad. Resultados: Un total de 331 niños participaron en el estudio. La diferencia entre la temperatura timpánica y la axilar varió entre 0,00ºC y 1,40ºC con una media de 0,45ºC ± 0,30ºC y una mediana de 0,50ºC, con una concordancia casi perfecta entre los dos métodos. En todas las variables estudiadas se observó un efecto sobre el valor de la temperatura según el método utilizado. Conclusión: Existe una concordancia casi perfecta entre estos dos métodos de medición de la temperatura, sin influencia en la toma de decisiones clínicas. Dada la mayor facilidad de aplicación y viabilidad, las ventajas del método de evaluación timpánica son superiores a las del método tradicional a través de la axila, por lo que puede aplicarse de forma rutinaria en la evaluación de la temperatura en niños de 6 a 36 meses.

Lost pigs of Angola: Whole genome sequencing reveals unique regions of selection with emphasis on metabolism and feed efficiency.

Angola, in the western coast of Africa, has been through dramatic social events that have led to the near-disappearance of native swine populations, and the recent introduction of European exotic breeds has also contributed to the erosion of this native swine repertoire. In an effort to investigate the genetic basis of native pigs in Angola (ANG) we have generated whole genomes from animals of a remote local pig population in Huambo province, which we have compared with 78 genomes of European and Asian pig breeds as well as European and Asian wild boars that are currently in public domain. Analyses of population structure showed that ANG pigs grouped within the European cluster and were clearly separated from Asian pig breeds. Pairwise F ST ranged from 0.14 to 0.26, ANG pigs display lower levels of genetic differentiation towards European breeds. Finally, we have identified candidate regions for selection using a complementary approach based on various methods. All results suggest that selection towards feed efficiency and metabolism has occurred. Moreover, all analysis identified CDKAL1 gene, which is related with insulin and cholesterol metabolism, as a candidate gene overlapping signatures of selection unique to ANG pigs. This study presents the first assessment of the genetic relationship between ANG pigs and other world breeds and uncovers selection signatures that may indicate adaptation features unique to this important genetic resource.

Identification and profiling of stable microRNAs in hemolymph of young and old Locusta migratoria fifth instars.

Since the discovery of the first microRNA (miRNA) in the nematode Caenorhabditis elegans, numerous novel miRNAs have been identified which can regulate presumably every biological process in a wide range of metazoan species. In accordance, several insect miRNAs have been identified and functionally characterized. While regulatory RNA pathways are traditionally described at an intracellular level, studies reporting on the presence and potential role of extracellular (small) sRNAs have been emerging in the last decade, mainly in mammalian systems. Interestingly, evidence in several species indicates the functional transfer of extracellular RNAs between donor and recipient cells, illustrating RNA-based intercellular communication. In insects, however, reports on extracellular small RNAs are emerging but the number of detailed studies is still very limited. Here, we demonstrate the presence of stable sRNAs in the hemolymph of the migratory locust, Locusta migratoria. Moreover, the levels of several extracellular miRNAs (ex-miRNAs) present in locust hemolymph differed significantly between young and old fifth nymphal instars. In addition, we performed a 'proof of principle' experiment which suggested that extracellularly delivered miRNA molecules are capable of affecting the locusts' development.

PIWI Proteins Play an Antiviral Role in Lepidopteran Cell Lines.

Insect antiviral immunity primarily relies on RNAi mechanisms. While a key role of small interfering (si)RNAs and AGO proteins has been well established in this regard, the situation for PIWI proteins and PIWI-interacting (pi)RNAs is not as clear. In the present study, we investigate whether PIWI proteins and viral piRNAs are involved in the immunity against single-stranded RNA viruses in lepidopteran cells, where two PIWIs are identified (Siwi and Ago3). Via loss- and gain-of-function studies in Bombyx mori BmN4 cells and in Trichoplusia ni High Five cells, we demonstrated an antiviral role of Siwi and Ago3. However, small RNA analysis suggests that viral piRNAs can be absent in these lepidopteran cells. Together with the current literature, our results support a functional diversification of PIWI proteins in insects.

Characterization of a MOB1 Homolog in the Apicomplexan Parasite Toxoplasma gondii.

Monopolar spindle One Binder1 (MOB1) proteins are conserved components of the tumor-suppressing Hippo pathway, regulating cellular processes such as cytokinesis. Apicomplexan parasites present a life cycle that relies on the parasites' ability to differentiate between stages and regulate their proliferation; thus, Hippo signaling pathways could play an important role in the regulation of the apicomplexan life cycle. Here, we report the identification of one MOB1 protein in the apicomplexan Toxoplasma gondii. To characterize the function of MOB1, we generated gain-of-function transgenic lines with a ligand-controlled destabilization domain, and loss-of-function clonal lines obtained through CRISPR/Cas9 technology. Contrary to what has been characterized in other eukaryotes, MOB1 is not essential for cytokinesis in T. gondii. However, this picture is complex since we found MOB1 localized between the newly individualized daughter nuclei at the end of mitosis. Moreover, we detected a significant delay in the replication of overexpressing tachyzoites, contrasting with increased replication rates in knockout tachyzoites. Finally, using the proximity-biotinylation method, BioID, we identified novel members of the MOB1 interactome, a probable consequence of the observed lack of conservation of some key amino acid residues. Altogether, the results point to a complex evolutionary history of MOB1 roles in apicomplexans, sharing properties with other eukaryotes but also with divergent features, possibly associated with their complex life cycle.

RNAs on the Go: Extracellular Transfer in Insects with Promising Prospects for Pest Management.

RNA-mediated pathways form an important regulatory layer of myriad biological processes. In the last decade, the potential of RNA molecules to contribute to the control of agricultural pests has not been disregarded, specifically via the RNA interference (RNAi) mechanism. In fact, several proofs-of-concept have been made in this scope. Furthermore, a novel research field regarding extracellular RNAs and RNA-based intercellular/interorganismal communication is booming. In this article, we review key discoveries concerning extracellular RNAs in insects, insect RNA-based cell-to-cell communication, and plant-insect transfer of RNA. In addition, we overview the molecular mechanisms implicated in this form of communication and discuss future biotechnological prospects, namely from the insect pest-control perspective.

MOB: Pivotal Conserved Proteins in Cytokinesis, Cell Architecture and Tissue Homeostasis.

The MOB family proteins are constituted by highly conserved eukaryote kinase signal adaptors that are often essential both for cell and organism survival. Historically, MOB family proteins have been described as kinase activators participating in Hippo and Mitotic Exit Network/ Septation Initiation Network (MEN/SIN) signaling pathways that have central roles in regulating cytokinesis, cell polarity, cell proliferation and cell fate to control organ growth and regeneration. In metazoans, MOB proteins act as central signal adaptors of the core kinase module MST1/2, LATS1/2, and NDR1/2 kinases that phosphorylate the YAP/TAZ transcriptional co-activators, effectors of the Hippo signaling pathway. More recently, MOBs have been shown to also have non-kinase partners and to be involved in cilia biology, indicating that its activity and regulation is more diverse than expected. In this review, we explore the possible ancestral role of MEN/SIN pathways on the built-in nature of a more complex and functionally expanded Hippo pathway, by focusing on the most conserved components of these pathways, the MOB proteins. We discuss the current knowledge of MOBs-regulated signaling, with emphasis on its evolutionary history and role in morphogenesis, cytokinesis, and cell polarity from unicellular to multicellular organisms.

Extracellular vesicles spread the RNA interference signal of Tribolium castaneum TcA cells.

The potential utility of RNA interference (RNAi) to control insect pests and viral infections depends largely on the target organism's ability to systemically spread the RNAi response. The efficacy of systemic RNAi varies among insects, though it has been shown to be high in the red flour beetle, Tribolium castaneum. We identified an extracellular RNAi signal that is present in the culture medium of T. castaneum (TcA) cells after treatment with long dsRNA specific for a luciferase reporter gene. Luciferase-specific siRNAs were detected in extracellular vesicles (EVs) that were purified from the culture medium of these dsRNA-treated cells. Furthermore, by measuring the silencing of luciferase expression, we showed that these siRNA-containing EVs can act as an RNAi signal for recipient TcA cells. We have therefore shown that a systemic RNAi response upon dsRNA treatment can be effectively spread through EVs.

Paisagem sonora: uma ferramenta para a saúde pública / Soundscape: a tool for public health

Introdução: A poluição sonora é um problema recorrente nas grandes cidades, pois causa a degradação da qualidade ambiental e afeta a saúde humana. Na atualidade o controle do ruído exige novas estratégias de gerenciamento, pois as abordagens tradicionais já não conseguem expressar a realidade acústica dos ambientes, visto que com o tempo o conceito de qualidade de som foi expandido. As novas pesquisas cientificas se direcionam para a paisagem sonora, que foi definida pela ISO 12923 como o ambiente acústico percebido e entendido pessoas. Objetivo: avaliar a influência dos altos níveis de ruído de tráfego como mediadora de doenças não auditivas e como a utilização da paisagem sonora na vida cotidiana dos moradores do entorno do Centro de Saúde Escola Geraldo Horácio Paula Souza (CSEGPS) pode trazer mais qualidade de vida. Método: Por meio de um estudo transversal, usando o ArcGIS para levantamento de níveis sonoros por endereços residenciais geocodificados pode-se chegar a estimativas de riscos teóricos de infarto de miocárdio e hipertensão. Em seguida foi elaborado passeios sonoros e levantadas informações mediante questionários semiestruturados para ver a agradabilidade do ambiente acústico do local e a percepção dos usuários do CSEGPS. Resultados: As informações levantadas pelos endereços possibilitaram o conhecimento da exposição a níveis sonoros dos usuários e a estimativa de risco para o infarto do miocárdio e hipertensão, bem como a influência positiva da paisagem sonora na vida cotidiana dos moradores é uma importante ferramenta de intervenção para sensibilização e prevenção de doenças relacionadas ao ruído.

Introduction: Noise pollution is a recurring problem in large cities, as it causes degradation of environmental quality and affects human health. Noise control currently requires new management strategies, as traditional approaches can no longer express the acoustic reality of environments, as over time the concept of sound quality has been expanded. New scientific research addresses the soundscape, which was defined by ISO 12923 as the perceived and understood acoustic environment of people. Objective: To evaluate the influence of high traffic noise levels as a mediator of non-auditory diseases and how the use of the soundscape in the daily life of the residents around the Horácio Gerald Paula Souza School Health Center (CSEGPS) can bring more quality of life. Method: Through a cross-sectional study using ArcGIS to survey sound levels by geocoded home addresses, risk estimates of myocardial infarction and hypertension can be derived. Then soundtracks were elaborated and information was collected through semi-structured questionnaires to see the pleasantness of the acoustic environment of the place and the perception of CSEGPS users. Results: The information obtained from the addresses made it possible to know the exposure to users 'sound levels and to estimate the risk for myocardial infarction and hypertension, as well as the positive influence of the soundscape on the residents' daily life, which is an important intervention tool. for awareness and prevention of noise related diseases.

Generation of Virus- and dsRNA-Derived siRNAs with Species-Dependent Length in Insects.

Double-stranded RNA (dsRNA) molecules of viral origin trigger a post-transcriptional gene-silencing mechanism called RNA interference (RNAi). Specifically, virally derived dsRNA is recognized and cleaved by the enzyme Dicer2 into short interfering RNAs (siRNAs), which further direct sequence-specific RNA silencing, ultimately silencing replication of the virus. Notably, RNAi can also be artificially triggered by the delivery of gene-specific dsRNA, thereby leading to endogenous gene silencing. This is a widely used technology that holds great potential to contribute to novel pest control strategies. In this regard, research efforts have been set to find methods to efficiently trigger RNAi in the field. In this article, we demonstrate the generation of dsRNA- and/or virus-derived siRNAs-the main RNAi effectors-in six insect species belonging to five economically important orders (Lepidoptera, Orthoptera, Hymenoptera, Coleoptera, and Diptera). In addition, we describe that the siRNA length distribution is species-dependent. Taken together, our results reveal interspecies variability in the (antiviral) RNAi mechanism in insects and show promise to contribute to future research on (viral-based) RNAi-triggering mechanisms in this class of animals.

PIWI pathway against viruses in insects.

Piwi-interacting RNAs (piRNAs) are an animal-specific class of small non-coding RNAs that are generated via a biogenesis pathway distinct from small interfering RNAs (siRNAs) and microRNAs (miRNAs). There are variations in piRNA biogenesis that depend on several factors, such as the cell type (germline or soma), the organism, and the purpose for which they are being produced, such as transposon-targeting, viral-targeting, or gene-derived piRNAs. Interestingly, the genes involved in the PIWI/piRNA pathway are more rapidly evolving compared with other RNA interference (RNAi) genes. In this review, the role of the piRNA pathway in the antiviral response is reviewed based on recent findings in insect models such as Drosophila, mosquitoes, midges and the silkworm, Bombyx mori. We extensively discuss the special features that characterize host-virus piRNA responses with respect to the proteins and the genes involved, the viral piRNAs' sequence characteristics, the target strand orientation biases as well as the viral piRNA target hotspots across the viral genomes. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.

Short-term persistence precedes pathogenic infection: Infection kinetics of cricket paralysis virus in silkworm-derived Bm5 cells.

Next generation sequencing has revealed the widespread occurrence of persistent virus infections in insects but little is known regarding to what extent persistent infections can affect cellular physiology and how they might contribute to the development of disease. In contrast to the pathogenic infections occurring in Drosophila S2 cells, it was observed that Cricket Paralysis virus (CrPV; Dicistroviridae) causes persistent infections in 9 lepidopteran and 2 coleopteran cell lines. The status of the persistent infection was subsequently investigated in more detail using silkworm-derived Bm5 cells, where the infection eventually becomes pathogenic after 3-4 weeks. The short-term persistence period in Bm5 cells is characterized by low levels of viral replication and virion production as well as by the production of viral siRNAs. However, during this period cellular physiology also becomes altered since the cells become susceptible to infection by the nodavirus Flock House virus (FHV). Pathogenicity and widespread mortality at 4 weeks is preceded by a large increase in virion production and the transcriptional activation of immune-related genes encoding RNAi factors and transcription factors in the Toll, Imd and Jak-STAT pathways. During the infection of Bm5 cells, the infective properties of CrPV are not altered, indicating changes in the physiology of the host cells during the transition from short-term persistence to pathogenicity. The in vitro system of Bm5 cells persistently infected with CrPV can therefore be presented as an easily accessible model to study the nature of persistent virus infections and the processes that trigger the transition to pathogenicity, for instance through the application of different "omics" approaches (transcriptomics, proteomics, metabolomics). The different factors that can cause the transition from persistence to pathogenicity in the Bm5-CrPV infection model are discussed.

The presence of extracellular microRNAs in the media of cultured Drosophila cells.

While regulatory RNA pathways, such as RNAi, have commonly been described at an intracellular level, studies investigating extracellular RNA species in insects are lacking. In the present study, we demonstrate the presence of extracellular microRNAs (miRNAs) in the cell-free conditioned media of two Drosophila cell lines. More specifically, by means of quantitative real-time PCR (qRT-PCR), we analysed the presence of twelve miRNAs in extracellular vesicles (EVs) and in extracellular Argonaute-1 containing immunoprecipitates, obtained from the cell-free conditioned media of S2 and Cl.8 cell cultures. Next-generation RNA-sequencing data confirmed our qRT-PCR results and provided evidence for selective miRNA secretion in EVs. To our knowledge, this is the first time that miRNAs have been identified in the extracellular medium of cultured cells derived from insects, the most speciose group of animals.

Insights into RNAi-based antiviral immunity in Lepidoptera: acute and persistent infections in Bombyx mori and Trichoplusia ni cell lines.

The control of viral infections in insects is a current issue of major concern and RNA interference (RNAi) is considered the main antiviral immune response in this group of animals. Here we demonstrate that overexpression of key RNAi factors can help to protect insect cells against viral infections. In particular, we show that overexpression of Dicer2 and Argonaute2 in lepidopteran cells leads to improved defense against the acute infection of the Cricket Paralysis Virus (CrPV). We also demonstrate an important role of RNAi in the control of persistent viral infections, as the one caused by the Macula-like Latent Virus (MLV). Specifically, a direct interaction between Argonaute2 and virus-specific small RNAs is shown. Yet, while knocking down Dicer2 and Argonaute2 resulted in higher transcript levels of the persistently infecting MLV in the lepidopteran cells under investigation, overexpression of these proteins could not further reduce these levels. Taken together, our data provide deep insight into the RNAi-based interactions between insects and their viruses. In addition, our results suggest the potential use of an RNAi gain-of-function approach as an alternative strategy to obtain reduced viral-induced mortality in Lepidoptera, an insect order that encompasses multiple species of relevant economic value.

RNA Interference in Insects: Protecting Beneficials and Controlling Pests.

Insects constitute the largest and most diverse group of animals on Earth with an equally diverse virome. The main antiviral immune system of these animals is the post-transcriptional gene-silencing mechanism known as RNA(i) interference. Furthermore, this process can be artificially triggered via delivery of gene-specific double-stranded RNA molecules, leading to specific endogenous gene silencing. This is called RNAi technology and has important applications in several fields. In this paper, we review RNAi mechanisms in insects as well as the potential of RNAi technology to contribute to species-specific insecticidal strategies. Regarding this aspect, we cover the range of strategies considered and investigated so far, as well as their limitations and the most promising approaches to overcome them. Additionally, we discuss patterns of viral infection, specifically persistent and acute insect viral infections. In the latter case, we focus on infections affecting economically relevant species. Within this scope, we review the use of insect-specific viruses as bio-insecticides. Last, we discuss RNAi-based strategies to protect beneficial insects from harmful viral infections and their potential practical application. As a whole, this manuscript stresses the impact of insect viruses and RNAi technology in human life, highlighting clear lines of investigation within an exciting and promising field of research.

Tatuagens: de temporárias a permanentes / Tattoos: from temporary to permanent

A realização de tatuagens temporárias é frequente, sendo percebida como inofensiva. A tinta usada deriva da henna, pigmento castanho-avermelhado obtido de uma planta. No entanto, para obter "henna negra" e facilitar a realização da tatuagem, são adicionados outros compostos, mais frequentemente a parafenilenodiamina. Esta está associada a reações alérgicas, por vezes graves e com sequelas. Os autores apresentam um caso de uma criança de 10 anos com uma reação alérgica exuberante com provável sobreinfecção bacteriana em local de tatuagem temporária. Havia história de sensibilização prévia, pelo que a reação foi precoce e mais agressiva. Os sinais inflamatórios francos motivaram o internamento sob corticoterapia sistêmica e antibioticoterapia endovenosa. Apesar da boa evolução clínica, permaneceu uma lesão hipopigmentada sequelar. Pretende-se alertar para os perigos desta realidade e também para a falta de legislação existente.

Temporary tattoos are quite popular, and they are perceived as harmless. The ink used in temporary tattoos is made from henna, a reddish-brown coloring pigment obtained from a shrub. However, in order to obtain "black henna" and facilitate the tattooing process, other compounds are added to the mixture, especially p-phenylenediamine. This compound is associated with allergic reactions that are sometimes severe and may leave sequelae. The authors describe a case of a 10-year old child presenting with allergic reaction and probable bacterial superinfection in a temporary tattoo area. The patient had a history of prior skin sensitization, and therefore the reaction was early and more aggressive. The severity of the inflammatory signs motivated hospital admission for systemic corticosteroid therapy and intravenous antibiotic therapy. Despite the good clinical evolution, a hypopigmented lesion persisted. Our goal is to raise awareness on the dangers of this practice and to highlight the lack of legislation in the area.