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As it is an infrequent etiology, the diagnosis of perianal tuberculosis is challenging, especially in the absence of a pulmonary focus. TB should be considered in the differential diagnosis of perianal ulcers, fistulas, abscesses, mainly in non-healing and recurrent anal lesions. Treatment with anti-TB agents can provide complete recovery. Furthermore, these lesions are often diagnosed later after complete histopathological and mycobacterial results, where the benefit of avoiding morbid multiple surgeries by effective anti-TB treatment is lost. We reported a rare case of an immuno-competent patient with perianal TB, which was the first manifestation of the disease. A fit-and-well man in his 20s presented a large perianal abscess. Unexpectedly, his chest X-ray showed a rounded hyper-transparency in the left lung. The abscess was drained. Posterior investigation with culture analysis from pus swabs and sputum revealed the presence of Mycobacterium tuberculosis complex infection. After completing the 6 months of oral administration of anti-TB drugs, the patient was asymptomatic. By highlighting this unusual manifestation, we aim to improve clinicians' awareness of perianal TB, facilitating early recognition and appropriate management. (AU)

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The mental health of health professionals who worked directly in services during the COVID-19 pandemic to care for patients affected by the disease became a fundamental issue to be considered, given the several consequences of this activity for these professionals. This article aimed to understand the challenges and demands of health professionals concerning support to address the emotional and physical exhaustion of working on the so-called frontline during the COVID-19 pandemic. The qualitative methodological approach was based on semi-structured interviews conducted online with these professionals after the first months of the pandemic. The hero's place in which they were set, even if only in media discourses, soon gave way to their weaknesses and fragile work relationships to emerge: stress, fear, and the listening and reception desire. Marcel Mauss' gift theory was brought up considering that new ways of reading and interpreting health work relationships contribute to necessary and urgent reformulations of their current context, targeting mental health and, more broadly, the comprehensive health of healthcare professionals.

Durante a pandemia de COVID-19, a saúde mental dos profissionais de saúde, que trabalharam diretamente nos serviços voltados para o cuidado dos pacientes afetados pela doença, tornou-se questão fundamental a ser considerada, dado os diversos desdobramentos que essa atuação gerou para esses profissionais. O objetivo deste artigo foi compreender desafios e demandas dos profissionais de saúde em termos de suporte para lidar com o desgaste emocional e físico com a atuação na chamada linha de frente durante a pandemia de COVID-19. A abordagem metodológica qualitativa se deu a partir de entrevistas semiestruturadas realizadas em ambiente online com esses profissionais, passados os primeiros meses de pandemia. O lugar de herói em que eles foram colocados, ainda que apenas nos discursos midiáticos, logo deu espaço para que as fragilidades destes e das relações de trabalho aparecessem: estresse, medo e o desejo de escuta e acolhimento. A teoria da dádiva de Marcel Mauss foi trazida considerando que novas formas de leitura e interpretação das relações de trabalho em saúde contribuem para reformulações necessárias e urgentes do contexto em que se encontram hoje, visando a saúde mental e, mais amplamente, a saúde integral dos profissionais da área de saúde.

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Resumo Durante a pandemia de COVID-19, a saúde mental dos profissionais de saúde, que trabalharam diretamente nos serviços voltados para o cuidado dos pacientes afetados pela doença, tornou-se questão fundamental a ser considerada, dado os diversos desdobramentos que essa atuação gerou para esses profissionais. O objetivo deste artigo foi compreender desafios e demandas dos profissionais de saúde em termos de suporte para lidar com o desgaste emocional e físico com a atuação na chamada linha de frente durante a pandemia de COVID-19. A abordagem metodológica qualitativa se deu a partir de entrevistas semiestruturadas realizadas em ambiente online com esses profissionais, passados os primeiros meses de pandemia. O lugar de herói em que eles foram colocados, ainda que apenas nos discursos midiáticos, logo deu espaço para que as fragilidades destes e das relações de trabalho aparecessem: estresse, medo e o desejo de escuta e acolhimento. A teoria da dádiva de Marcel Mauss foi trazida considerando que novas formas de leitura e interpretação das relações de trabalho em saúde contribuem para reformulações necessárias e urgentes do contexto em que se encontram hoje, visando a saúde mental e, mais amplamente, a saúde integral dos profissionais da área de saúde.

Abstract The mental health of health professionals who worked directly in services during the COVID-19 pandemic to care for patients affected by the disease became a fundamental issue to be considered, given the several consequences of this activity for these professionals. This article aimed to understand the challenges and demands of health professionals concerning support to address the emotional and physical exhaustion of working on the so-called frontline during the COVID-19 pandemic. The qualitative methodological approach was based on semi-structured interviews conducted online with these professionals after the first months of the pandemic. The hero's place in which they were set, even if only in media discourses, soon gave way to their weaknesses and fragile work relationships to emerge: stress, fear, and the listening and reception desire. Marcel Mauss' gift theory was brought up considering that new ways of reading and interpreting health work relationships contribute to necessary and urgent reformulations of their current context, targeting mental health and, more broadly, the comprehensive health of healthcare professionals.

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The stingless bee Partamona helleri plays a role in pollinating both native and cultivated plants in the Neotropics. However, its populations can be reduced by the pyrethroid insecticide lambda-cyhalothrin. This compound may cross the intestinal barrier and circulate through the hemolymph, affecting various non-target bee organs. The aim of the present study was to assess the extent of cellular damage in the midgut and the resulting oxidative stress caused by lambda-cyhalothrin in P. helleri workers. Bees were orally exposed to lambda-cyhalothrin. The lethal concentration at which 50% of the bees died (LC50) was 0.043 mg a.i. L-1. The P. helleri workers were fed this concentration of lambda-cyhalothrin and their midguts were evaluated. The results revealed signs of damage in the midgut epithelium, including pyknotic nuclei, cytoplasm vacuolization, changes in the striated border, and the release of cell fragments, indicating that the midgut was compromised. Furthermore, the ingestion of lambda-cyhalothrin led to an increase in the activity of the detoxification enzyme superoxide dismutase and the levels of the NO2/NO3 markers, indicating oxidative stress. Conversely, the activities of the catalase and glutathione S-transferase enzymes decreased, supporting the occurrence of oxidative stress. In conclusion, the ingestion of lambda-cyhalothrin by P. helleri workers resulted in damage to their midguts and induced oxidative stress.

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Nosocomial infections (NIs) appear in patients under medical care in the hospital. The surveillance of the bacterial communities employing high-resolution 16S rRNA profiling, known as metabarcoding, represents a reliable method to establish factors that may influence the composition of the bacterial population during NIs. The present study aimed to utilize high-resolution 16S rRNA profiling to identify high bacterial diversity by analyzing 11 inside and 10 outside environments from the General Hospital of Ribeirão Preto Medical School, Brazil. Our results identified a high bacterial diversity, and among these, the most abundant bacterial genera linked to NIs were Cutibacterium, Streptococcus, Staphylococcus, and Corynebacterium. A Acinetobacter was detected in cafeterias, bus stops, and adult and pediatric intensive care units (ICUs). Data suggest an association between transport and alimentation areas proximal to the hospital ICU environment. Interestingly, the correlation and clusterization analysis showed the potential of the external areas to directly influence the ICU pediatric department microbial community, including the outpatient's clinic, visitor halls, patient reception, and the closest cafeterias. Our results demonstrate that high-resolution 16S rRNA profiling is a robust and reliable tool for bacterial genomic surveillance. In addition, the metabarcoding approach might help elaborate decontamination policies, and consequently reduce NIs.

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Superior mesenteric artery syndrome designates compression of the third part of the duodenum between the superior mesenteric artery and the aorta. This condition has a low incidence, being more common in thin young women. Nutcracker syndrome is compression of the left renal vein between the superior mesenteric artery and the aorta. Both entities are rare, and their coexistence has been reported in a few cases. Conservative treatment targeting weight gain is sufficient in most cases. An association between the superior mesenteric artery syndrome and acute pancreatitis has rarely been reported. We intend to describe the case of an 18-year-old girl who was admitted to the emergency room with epigastric pain and emesis. Our investigation revealed acute acalculous pancreatitis. During work-up, we discovered superior mesenteric artery syndrome and a compressed left renal vein. The patient is on conservative treatment, and her symptoms have improved.

A síndrome da artéria mesentérica superior designa compressão da terceira parte do duodeno pela artéria mesentérica superior e a aorta. Essa condição tem uma baixa incidência, sendo mais comum em mulheres jovens magras. A síndrome de quebra-nozes resulta da compressão da veia renal esquerda pela artéria mesentérica superior e a aorta. Ambas as entidades são raras, e a sua coexistência foi descrita em poucos casos. Tratamento conservador com o objetivo de ganho ponderal é suficiente na maioria dos casos. A associação entre a síndrome da artéria mesentérica superior e a pancreatite aguda foi raramente relatada. Pretendemos descrever o caso de uma jovem de 18 anos que recorreu ao serviço de urgência com epigastralgia e vômitos. A investigação realizada revelou pancreatite aguda alitiásica. Durante o estudo complementar, foi identificada a síndrome da artéria mesentérica superior, bem como uma veia renal esquerda comprimida. A paciente encontra-se em tratamento conservador, apresentando melhora clínica.

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Tuberculosis (TB) causes 1 in 3 deaths among people living with HIV (PLHIV). Diagnosing and treating latent tuberculosis infection (LTBI) is critical to reducing TB incidence and mortality. Blood-based screening tests (e.g., QuantiFERON-TB Gold Plus (QFT+)) and shorter-course TB preventive therapy (TPT) regimens such as 3HP (3 months weekly isoniazid-rifapentine) hold significant promise to improve TB outcomes. We qualitatively explored barriers and solutions to optimizing QFT+ and 3HP among PLHIV in three cities in Brazil. We conducted 110 in-depth interviews with PLHIV, health care providers (HCP) and key informants (KI). Content analysis was conducted including the use of case summaries and comparison of themes across populations and contexts. LTBI screening and treatment practices were dependent on HCP's perceptions of whether they were critical to improving TB outcomes. Many HCP lacked a strong understanding of LTBI and perceived the current TPT regimen as complicated. HCP reported that LTBI screening and treatment were constrained by clinic staffing challenges. While PLHIV generally expressed willingness to consider any test or treatment that doctors recommended, they indicated HCP rarely discussed LTBI and TPT. TB testing and treatment requests were constrained by structural factors including financial and food insecurity, difficulties leaving work for appointments, stigma and family responsibilities. QFT+ and 3HP were viewed by all participants as tools that could significantly improve the LTBI cascade by avoiding complexities of TB skin tests and longer LTBI treatment courses. QFT+ and 3HP were perceived to have challenges, including the potential to increase workload on over-burdened health systems if not implemented alongside improved supply chains, staffing, and training, and follow-up initiatives. Multi-level interventions that increase understanding of the importance of LTBI and TPT among HCP, improve patient-provider communication, and streamline clinic-level operations related to QFT+ and 3HP are needed to optimize their impact among PLHIV and reduce TB mortality.

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Abstract Superior mesenteric artery syndrome designates compression of the third part of the duodenum between the superior mesenteric artery and the aorta. This condition has a low incidence, being more common in thin young women. Nutcracker syndrome is compression of the left renal vein between the superior mesenteric artery and the aorta. Both entities are rare, and their coexistence has been reported in a few cases. Conservative treatment targeting weight gain is sufficient in most cases. An association between the superior mesenteric artery syndrome and acute pancreatitis has rarely been reported. We intend to describe the case of an 18-year-old girl who was admitted to the emergency room with epigastric pain and emesis. Our investigation revealed acute acalculous pancreatitis. During work-up, we discovered superior mesenteric artery syndrome and a compressed left renal vein. The patient is on conservative treatment, and her symptoms have improved.

Resumo A síndrome da artéria mesentérica superior designa compressão da terceira parte do duodeno pela artéria mesentérica superior e a aorta. Essa condição tem uma baixa incidência, sendo mais comum em mulheres jovens magras. A síndrome de quebra-nozes resulta da compressão da veia renal esquerda pela artéria mesentérica superior e a aorta. Ambas as entidades são raras, e a sua coexistência foi descrita em poucos casos. Tratamento conservador com o objetivo de ganho ponderal é suficiente na maioria dos casos. A associação entre a síndrome da artéria mesentérica superior e a pancreatite aguda foi raramente relatada. Pretendemos descrever o caso de uma jovem de 18 anos que recorreu ao serviço de urgência com epigastralgia e vômitos. A investigação realizada revelou pancreatite aguda alitiásica. Durante o estudo complementar, foi identificada a síndrome da artéria mesentérica superior, bem como uma veia renal esquerda comprimida. A paciente encontra-se em tratamento conservador, apresentando melhora clínica.

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This study investigated the ability of cholesterol-phosphatidylcholine liposomes loaded with chloride aluminum phthalocyanine (CL-AlClPc) to discriminate between healthy (MCF-10A) and neoplastic (MCF-7 and MDA-MB-231) breast cells for breast cancer diagnosis and treatment by photodynamic therapy (PDT) using a new drug delivery system consisting of CL-AlClPc. When PDT treatment was applied at an energy fluence of 700 mJ/cm², CL-AlClPc was more cytotoxic to neoplastic cells than to healthy breast cells because CL-AlClPc was better internalized by the tumor cells. An even higher fluorescence signal is expected for neoplastic cells during clinical treatment than for healthy cells, which will be useful for precise and targeted tumor cell detection. CL-AlClPc also facilitated better drug distribution and targeting of essential organelles inside the cells. This selectivity is critical for future in vivo diagnosis and treatment; it prevents side effects because it prioritizes tumor cells and tissues instead of healthy ones. The CL-AlClPc system designed herein had a small size (150 nm), low zeta potential (-6 mV), low polydispersity (0.16), high encapsulation rate efficiency (82.83%), and high shelf stability (12 months).

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ABSTRACT BACKGROUND: Epidemiological studies involving large samples usually face financial and operational challenges. OBJECTIVES: To describe the planning and execution of ADHERE Brazil, an epidemiological study on 1,105 kidney transplant patients, and report on how the study was structured, difficulties faced and solutions found. DESIGN AND SETTING: Cross-sectional multicenter study in 20 Brazilian kidney transplantation centers. METHODS: Actions developed in each phase of implementation were described, with emphasis on innovations used within the logistics of this study, aimed at estimating the prevalence of nonadherence to treatment. RESULTS: Coordination of activities was divided into four areas: general, regulatory, data collection and statistics. Weekly meetings were held for action planning. The general coordination team was in charge of project elaboration, choice of participating centers, definition of publication policy and monitoring other coordination teams. The regulatory team provided support to centers for submitting the project to ethics committees. The data collection team prepared a manual on the electronic collection system, scheduled web meetings and was available to respond to queries. It also monitored the data quality and reported any inadequacies found. Communication with the centers was through monthly reports via e-mail and distribution of exclusive material. The statistical team acted in all phases of the study, especially in creating the data analysis plan and data bank, generation of randomization lists and data extraction. CONCLUSIONS: Through these logistics, we collected high-quality data and built a local research infrastructure for further studies. We present supporting alternatives for conducting similar studies. CLINICAL TRIAL ANNOTATION: http://clinicaltrials.gov/ on October 10, 2013; NCT02066935.

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BACKGROUND: Epidemiological studies involving large samples usually face financial and operational challenges. OBJECTIVES: To describe the planning and execution of ADHERE Brazil, an epidemiological study on 1,105 kidney transplant patients, and report on how the study was structured, difficulties faced and solutions found. DESIGN AND SETTING: Cross-sectional multicenter study in 20 Brazilian kidney transplantation centers. METHODS: Actions developed in each phase of implementation were described, with emphasis on innovations used within the logistics of this study, aimed at estimating the prevalence of nonadherence to treatment. RESULTS: Coordination of activities was divided into four areas: general, regulatory, data collection and statistics. Weekly meetings were held for action planning. The general coordination team was in charge of project elaboration, choice of participating centers, definition of publication policy and monitoring other coordination teams. The regulatory team provided support to centers for submitting the project to ethics committees. The data collection team prepared a manual on the electronic collection system, scheduled web meetings and was available to respond to queries. It also monitored the data quality and reported any inadequacies found. Communication with the centers was through monthly reports via e-mail and distribution of exclusive material. The statistical team acted in all phases of the study, especially in creating the data analysis plan and data bank, generation of randomization lists and data extraction. CONCLUSIONS: Through these logistics, we collected high-quality data and built a local research infrastructure for further studies. We present supporting alternatives for conducting similar studies. CLINICAL TRIAL ANNOTATION: http://clinicaltrials.gov/ on October 10, 2013; NCT02066935.

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Brazil has been severely affected by the COVID-19 pandemic. The high numbers of confirmed cases and deaths have continued unabated since the first reported case, with no flattening or downward turn in the curve. In this context, healthcare workers have been exposed uninterruptedly to stress factors throughout a year of the pandemic. The study´s aim was to identify and analyze healthcare workers´ perceptions of their feelings and concerns that have surfaced in responding to the pandemic. METHOD: This was a cross-sectional online qualitative survey study of 554 healthcare personnel working in the state of Rio de Janeiro during the COVID-19 pandemic. Recruitment occurred from July 20 to September 30, 2020, using an online survey, preceded byfree informed consent term. Data were analyzed with the Iramuteq software. RESULTS: Through a dendrogram, the words with the highest chi-square were highlighted and grouped into four classes: healthcare workers´ fear of falling ill to COVID-19 and infecting their family members; work/labor issues; feelings of powerlessness and need for public policies for government action; and fatigue and burnout in the pandemic. Each word class was also illustrated by a similarity tree. CONCLUSION: The study revealed healthcare workers´ exacerbated fear of infection and transmission of COVID-19 to their family members, besides financial losses and feelings of powerlessness and abandonment.

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Phosphate chelators are frequently used in patients with chronic kidney disease (CKD). New iron-based chelators remain understudied and offer a promising therapeutic option for the control of bone and mineral disorders of chronic kidney disease (BMD-CKD). We assessed the effect of the phosphorus chelator, chitosan-iron III (CH-FeCl), compared to calcium carbonate (CaCO3) in BMD-CKD and the potential iron overload in uremic rats. Thirty-two animals were divided into four groups, namely the control, CKD, CKD/CH-FeCl, and CKD/CaCO3 groups. CKD was induced by adding 0.75% (4 weeks) and 0.1% (3 weeks) adenine to the diet. The chelators were administered from week 3 through week 7. The renal function, BMD-CKD markers, and histomorphometry of the femur were assessed at week 7. The CKD group showed a significant increase in creatinine (83.9 ± 18.6 vs. 41.5 ± 22.1 µmol/L; P = 0.001), phosphate (3.5 ± 0.8 vs. 2.2 ± 0.2 mmol/L; P = 0.001), fractional excretion of phosphorus (FEP) (0.71 ± 0.2 vs. 0.2 ± 0.17; P = 0.0001), and FGF23 (81.36 ± 37.16 pg/mL vs. 7.42 ± 1.96; P = 0.011) compared to the control group. There was no accumulation of serum or bone iron after the use of CH-FeCl. The use of chelators reduced the FEP (control: 0.71 ± 0.20; CKD/CH-FeCl: 0.40 ± 0.16; CKD/CaCO3 0.34 ± 0.15; P = 0.001), without changes in the serum FGF23 and parathyroid hormone levels. Histomorphometry revealed the presence of bone disease with high remodeling in the uremic animals without changes with the use of chelators. The CH-FeCl chelator was efficient in reducing the FEP without iron accumulation, thereby paving the way for the use of this class of chelators in clinical settings in the future.

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Entomopathogenic nematodes (EPNs) can control pests due to their mutual association with bacteria. The use of these biological control agents is increasing worldwide due to advances in research about its control efficiency, range of action and mass production. The identification of EPNs adapted to specific environmental and climatic conditions is important for sustainable pest suppression in integrated management (IPM) programs. The objective is to report, for the first time, the occurrence of the Steinernema diaprepesi in Brazil. Steel mesh traps with Galleria mellonella Linnaeus (Lepidoptera: Pyralidae) larvae were buried in red latosol cultivated with Eucalyptus. Infective juveniles (IJs) were isolated from dead larvae and multiplied in healthy ones of this host to confirm its pathogenicity and to start a laboratory population from the strain found in the field. The DNA of the IJs was extracted and amplified using PCR technique with the universal primers D2A and D3B. The detection of S. diaprepesi is the first report of this nematode in Brazil, increasing the knowledge about its distribution in the world and the diversity of EPNs that must be considered as agents of biological pest control in the country.

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In recent decades, there has been a progressive increase in the prevalence of obesity and chronic kidney disease. Renal lipotoxicity has been associated with obesity. Although lipids play fundamental physiological roles, the accumulation of lipids in kidney cells may cause dysfunction and/or renal fibrosis. Adipose tissue that exceeds their lipid storage capacity begins to release triglycerides into the bloodstream that can get stored in several organs, including the kidneys. The mechanisms underlying renal lipotoxicity involve intracellular lipid accumulation and organelle dysfunction, which trigger oxidative stress and inflammation that consequently result in insulin resistance and albuminuria. However, the specific pathways involved in renal lipotoxicity have not yet been fully understood. We aimed to summarize the current knowledge on the mechanisms by which lipotoxicity affects the renal morphology and function in experimental models of obesity. The accumulation of fatty acids in tubular cells has been described as the main mechanism of lipotoxicity; however, lipids and their metabolism also affect the function and the survival of podocytes. In this review, we presented indication of mitochondrial, lysosomal and endoplasmic reticulum alterations involved in kidney damage caused by obesity. The kidney is vulnerable to lipotoxicity, and studies of the mechanisms underlying renal injury caused by obesity can help identify therapeutic targets to control renal dysfunction.

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The microlepidoptera, Bedellia somnulentella (Zeller), is an important pest of sweetpotato, Ipomoea batatas (L.) Lam. Damage by B. somnulentella occurs in the larval stage and when consuming the foliar mesophyll of I. batatas make the leaves brown, wrinkled, and reducing the photosynthetic area and the yield. The detection and management of this pest depends on knowing its biological cycle and identifying its natural enemies. The objectives of this study were to determine the life history of B. somnulentella feeding on I. batatas leaves and to survey parasitoids of this pest in the field. The duration and viability of B. somnulentella egg, larva, prepupa, pupa, and adult stages were evaluated under laboratory conditions. Cephalic capsule width was measured to determine the number of B. somnulentella instars, based on the Dyar rule and analyzed by the Akaike statistical model (AIC). The developmental period of B. somnulentella was 32.5 ± 0. 21 d with a viability of 75, 84, 100, and 84% for the egg, larva, prepupa, and pupa stages, respectively. The identification of this pest on the plants is possible from the third instar and in the pupal and adult stages. The parasitoid Conura sp. (Hymenoptera: Chalcididae) was identified parasitizing pupae of B. somnulentella and could be considered a potential natural enemy for the integrated management of this pest.

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The objective of this study was to evaluate the biological and nutritional characteristics of Spodoptera frugiperda (Lepidoptera: Noctuidae), an arthropod pest widely distributed in agricultural regions, after exposure to nano-CeO2 via an artificial diet and to investigate the presence of cerium in the body of this insect through X-ray fluorescence mapping. Nano-CeO2, micro-CeO2, and Ce(NO3)3 were incorporated into the diet (0.1, 1, 10, and 100 mg of Ce L-1). Cerium was detected in caterpillars fed with diets containing nano-CeO2 (1, 10 and 100 mg of Ce L-1), micro-CeO2 and Ce(NO3)3, and in feces of caterpillars from the first generation fed diets with nano-CeO2 at 100 mg of Ce L-1 as well. The results indicate that nano-CeO2 caused negative effects on S. frugiperda. After it was consumed by the caterpillars, the nano-CeO2 reduced up to 4.8% of the pupal weight and 60% of egg viability. Unlike what occurred with micro-CeO2 and Ce(NO3)3, nano-CeO2 negatively affected nutritional parameters of this insect, as consumption rate two times higher, increase of up to 80.8% of relative metabolic rate, reduction of up to 42.3% efficiency of conversion of ingested and 47.2% of digested food, and increase of up to 1.7% of metabolic cost and 8.7% of apparent digestibility. Cerium caused 6.8-16.9% pupal weight reduction in second generation specimens, even without the caterpillars having contact with the cerium via artificial diet. The results show the importance of new ecotoxicological studies with nano-CeO2 for S. frugiperda in semi-field and field conditions to confirm the toxicity.

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The anthranilic diamide, chlorantraniliprole is a systemic insecticide affecting ryanodine receptors. This insecticide is used to control caterpillars in soybean crops because it has low toxicity to non-target organisms. The objective was to identify side-effects of chlorantraniliprole on midgut histopathology, respiration and behavior of the velvetbean caterpillar Anticarsia gemmatalis in laboratoty. Chlorantraniliprole has LC50 = 0.61 (0.58-0.64) mg mL-1 for A. gemmatalis fourth instar caterpillars after 96 h. The insecticide causes severe histopathological effects in the midgut with epithelial disorganization, microvilli degeneration, cytoplasm vacuolization, cell fragmentation, and peritrophic matrix disorganization. The respiratory rate and the walking speed decrease, whereas the resting period increase for caterpillars exposed to this insecticide. Chlorantraniliprole is toxic to A. gemmatalis at median lethal concentrations causing severe histological and ultrastructural changes with degeneration of the midgut epithelium, reduction of respiratory rates and inducing an arresting behavioral response of this insect.

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Entomopathogenic nematodes (EPNs) can control pests due to mutualistic association with bacteria that reproduce and kill the host from septicemia, making the environment favourable for nematode development and reproduction. The objective of this study was to identify an EPN isolate collected in eucalyptus cultivation and to determine its pathogenicity with regard to Gonipterus platensis Marelli (Coleoptera: Curculionidae). Four steel-mesh traps with two seventh-instar Galleria mellonella larvae were buried 5 cm deep in the soil in a commercial Eucalyptus plantation. After 7 days, the traps were packed in plastic bags and transported to laboratory to isolate the EPNs using White traps. The obtained nematodes were multiplied in G. mellonella larvae and identified by sequencing their D2/D3 expansion of the 28S rDNA region by polymerase chain reaction (PCR) and specific primers for ITS regions. Steinernema diaprepesi was identified and inoculated into G. platensis pupae at doses of 500, 1000 and 5000 infective juveniles (IJs) to determine its pathogenicity to this pest. At 8 days after inoculation, the mortality rate of the G. platensis pupae was 80% with the lowest concentration and 100% with the others. The emergence of nematodes and the rapid degradation of G. platensis pupae were observed in those inoculated with IJs. The pathogenicity to the G. platensis pupae indicates potential for using this nematode in the integrated management of this insect.

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Insecticides are the main method of controlling lepidopteran pests of eucalyptus plantations and those selective to natural enemies, such as the endoparasitoid Palmistichus elaeisis Delvare et LaSalle (Hymenoptera: Eulophidae), are preferable. The objective of this study was to evaluate the selectivity and effects on biological parameters of the insecticide deltamethrin, registered for the control of defoliator caterpillars of eucalyptus, to the parasitoid P. elaeisis aiming the rational use of this insecticide and its compatibility with parasitoids. The experiment was in a completely randomized design. The treatments were the doses of 0.64, 1.40, 3.10, 6.83, 15.03, 33.05, 72.7 and 160 mg a.i./L of deltamethrin and the control (distilled water) with 10 replications, each with a pupae of the alternative host Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae) exposed by the immersion method. The parasitism, biological cycle, emergence, longevity, head width and metatibia length of the natural enemy were evaluated. Deltamethrin reduced parasitism and the emergence rates of P. elaeisis. The duration of the biological cycle of this parasitoid, emerged from T. molitor pupae exposed to 15.03 mg a.i./L of deltamethrin, was higher. The morphometric parameters of P. elaeisis exposed to the doses of 0.64 and 1.40 mg a.i./L of the insecticide were lower. However, the morphometric parameter values were higher with the doses above 3.10 mg a.i./L than in the control. The parasitism and emergence of P. elaeisis were also reduced by the deltamethrin doses lower than the commercially recommended one and therefore, this insecticide is not selective for this natural enemy.

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