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Douglas Poschinger-Figueiredo,1 Carlos Eduardo Virgini-Magalhães,1,2 Luís Cristóvão Porto,3,4 Claudia Salvador Amorim,1 Cristiane Ferreira de Araujo Gomes,1 Cristina Ribeiro Riguetti-Pinto,1,2 Monica Rochedo Mayall,1 Leonardo Silveira de Castro,1 Felipe Borges Fagundes1 1Teaching and Health Care Unit of Vascular and Endovascular Surgery’s Medical Staff, Pedro Ernesto University Hospital (HUPE), Rio de Janeiro State University (UERJ), Rio De Janeiro, Brazil; 2Medical Sciences College (FCM), Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil; 3Histocompatibility and Cryopreservation Laboratory (HLA), Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil; 4Roberto Alcantara Gomes Biology Institute (IBRAG), Rio de Janeiro State University (UERJ), Rio de Janeiro, BrazilCorrespondence: Douglas Poschinger-FigueiredoTeaching and Health Care Unit of Vascular and Endovascular Surgery’s Medical Staff, Pedro Ernesto University Hospital (HUPE), Rio de Janeiro State University (UERJ), Boulevard Vinte e Oito de Setembro, N 77, 4th Floor, Vila Isabel, Rio De Janeiro, RJ, 20551– 030, BrazilTel +55 21 2686-8643Fax +55 21 2587-4010Email dpvasc@icloud.comObjective: This study assessed the outcomes and impact on the quality of life following one-step outpatient radiofrequency ablation (RFA) and ultrasound guided foam sclerotherapy (USGFS) for large reflux with varicosities in the great saphenous vein (GSV).Design: Prospective, single-centre, analytical cohort.Materials and Methods: Thirty symptomatic patients having reflux in the GSV and varicosities (CEAP C3 to C6) were treated with RFA and USGFS simultaneously, in a single-step procedure, from March 2016 to December 2016. They were followed up at 1 week, 6 months, 1 and 3 years. Clinical outcomes, changes in the Quality of Life (QOL) questionnaires SF-36™, VCSS and AVVQ, evolutive vein occlusion rates were assessed by duplex ultrasound, and ulcer closure was checked.Results: The sample was divided into two groups: (Group 1) GSV diameter ≥ 13.0 mm (median 19.0 [14– 24]), 17 subjects, and (Group 2) GSV diameter ≤ 12.9 mm (median 10.3 [10– 12]), 16 subjects. No major adverse event was observed, and the postoperative minor adverse event rates were similar between the two groups. A significant improvement was observed in VCSS and AVVQ from the preoperative levels to the sixth month and the third-year follow-up. Twelve of 13 ulcers had healed at 1 year and remained closed until 3 years. The entire sample had a significant increase in all short form 36 domains, except for mental health in the Group 2 (GSV ≥ 13.0 mm). Overall first week occlusion rate for the whole sample was 90.9% and 69.7% at the 3-year follow-up. No difference in occlusion rate was observed between the two groups at any time.Conclusion: Exclusively outpatient combined techniques were safe and feasible in this study with no major adverse events, despite the large diameters of the GSV or ulcer presence. Within 3 years, both diameter groups showed equivalent improvement in all QOL parameters, satisfactory axial occlusion, and maintained ulcer closure.Keywords: saphenous vein, varicose veins, varicose ulcer, quality of life, catheter ablation, sclerotherapy

Caterpillars of the genus Spodoptera are the main pests in soybean and cotton crops and Spodoptera cosmioides causes more severe losses than other caterpillars in these agricultural crops. However, there are few recommended insecticides for controlling this pest. Lambda-cyhalothrin is a pyrethroid used to control a wide spectrum of arthropods including lepidopterans. Therefore, the objective of this study was to evaluate the potential of lambda-cyhalothrin for the control of S. cosmioides. Specifically, toxicity and histopathological changes in the midgut were evaluated. The effectiveness of the insecticide was determined by estimating the different lethal concentrations (LCs) ​​in the laboratory upon S. cosmioides. Lambda-cyhalothrin was found toxic to S. cosmioides (LC 50  = 23.03 mg L -1 and LC 90  = 174.8 mg L -1 ), with the survival reduced from 83.33% in the control to 37.89%, 16.66%, 0%, and 0% after 72 h of exposure to the LC 25 , LC 50 , LC 75 , and LC 90 of lambda-cyhalothrin, respectively. Histopathological studies revealed that lambda-cyhalothrin caused damage to midgut cells, including epithelial disorganization, increased cytoplasmic vacuolization, brush border degeneration, nuclear chromatin condensation, and cell fragmentation, indicating cell death by apoptosis. It was concluded that lambda-cyhalothrin, a neurotoxic insecticide, caused damage to the midgut of S. cosmioides, compromising its physiology and indicating that it has potential to be used to control this pest., Competing Interests: Declarations. Conflict of Interest: The authors declare no competing interests., (© 2025. Sociedade Entomológica do Brasil.)

The challenge of American tegumentary leishmaniasis (ATL) continues in Brazil, presenting a persistent public health issue despite initiatives aimed at public outreach, vector control and health education. To gain a deeper understanding of this disease, a study was conducted in an endemic region located in the northern region of the state of Minas Gerais, Brazil. The study monitored 30 resident patients diagnosed with ATL, using serum samples from 6 healthy individuals as controls. The localized cutaneous form of the disease was found to be predominant, with lesions appearing on various parts of the body and the majority of the affected individuals being male. The study found significantly higher levels of IgG anti- α -Gal antibodies in ATL-infected patients compared to healthy individuals. Treatment of 19 patients with meglumine antimoniate resulted in limited improvement in symptoms for most. Nonetheless, the study found that 12 patients who completed treatment with epithelialization of the lesions showed a significant decrease in IgG anti- α -Gal antibodies, indicating potential applications of this antibody in the diagnosis and monitoring of the disease. The study also identified Leishmania species in 7 analysed patients, revealing 6 cases infected by Leishmania braziliensis and 1 by L. infantum , with a significant difference in the anti- α -Gal responses. The findings of the study emphasize the urgent need for the development of human vaccines and innovative treatment strategies adapted to the diversity of Leishmania species causing cutaneous leishmaniasis and individual patient responses to improve the clinical management of ATL in Brazil and similar endemic regions.

Maternal obesity during perinatal period increases the risk of metabolic and behavioral deleterious outcomes in the offspring, since it is critical for brain development, maturation, and reorganization. These processes are highly modulated by the endocannabinoid system (ECS), which comprises the main lipid ligands anandamide and 2-arachidonoylglycerol, cannabinoid receptors 1 and 2 (CB1R and CB2R), and several metabolizing enzymes. The ECS is overactivated in obesity and it contributes to the physiological activity of the hypothalamus-pituitary-adrenal (HPA) axis, promoting stress relief. We have previously demonstrated that maternal high-fat diet during gestation and lactation programmed the food preference for fat in adolescent male offspring and adult male and female offspring. In the present study, we hypothesized that maternal diet-induced obesity would induce sex-specific changes of the ECS in the hypothalamus and dorsal hippocampus of rat offspring associated with dysregulation of the HPA axis and stress-related behavior in adolescence. Rat dams were fed a control (C) or an obesogenic high-fat high-sugar diet (OD) for nine weeks prior to mating and throughout gestation and lactation. Maternal obesity differentially altered the CB1R in the hypothalamus of neonate offspring, with significant increase in male but not in female pups, associated with decreased CB2R prior to obesity development. In adolescence, maternal obesity induced anxiety-like behavior only in adolescent females which was associated with increased content of CB1R in the dorsal hippocampus. Our findings suggest that the early origins of anxiety disorders induced by maternal exposome is associated with dysregulation of the brain ECS, with females being more susceptible., Competing Interests: Declaration of competing interest The authors report there are no competing interests to declare., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The small intestine, including the endocannabinoid system (ECS), regulates the energy homeostasis. If maternal obesity modifies the intestinal ECS of the offspring favoring metabolic disorders throughout life is unexplored. Regardless maternal insults, overaction of the ECS has been related to obesity, mainly via type 1 cannabinoid receptor (CB1) signaling, while type 2 cannabinoid receptor (CB2) signaling and the endocannabinoid-like compounds, such as oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), have been associated with anti-inflammatory effects. We hypothesized that maternal obesity changes the ECS in the small intestine of weanling rat offspring in a sex-specific manner associated with altered fecal metabolites. Female rats received a control diet (C; 9% fat) or an obesogenic diet (OD; 37.2% fat, 11.8% sucrose) 9 weeks before mating, gestation and lactation. Offspring were euthanized at weaning. Maternal obesity increased CB2 protein content and mRNA levels of monocyte chemoattractant protein-1 in the small intestine in male offspring, while decreased fecal content of PEA and OEA in both sexes. Maternal obesity decreased gut permeability, but impaired glycemic homeostasis. Concerning fecal levels of γ-aminobutyric acid, amino acids and hypoxanthine, maternal obesity induced a fecal signature related to inflammatory and glycemic homeostasis impairment and dysbiosis. Maternal obesity induced intestinal inflammation and the signaling of CB2, PEA, and OEA might be part of a counter-regulatory response, contributing to reduced gut permeability, but not enough to avoid overweight and glycemic impairment in the offspring at weaning. Our findings provide molecular insights into the intestinal and fecal biomarkers for metabolic disorders., Competing Interests: Declaration of competing interests The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Despite the high prevalence of cannabis consumption, there is limited information about cannabis based on scientific evidence available and targeted toward young adults, especially considering accessible language and ease of access. The present study aimed to develop the proof of concept of a chatbot for the dissemination of evidence and scientific information about cannabis, focused on a young adult audience. The proof of concept involved stages of literature review, conversation flow development, content evaluation through a panel of experts ( n  = 10) and usability analysis using a sample of potential users (young adults, n  = 10). The chatbot developed presents information on epidemiology, toxicology, acute and chronic effects of cannabis use, information on cannabis use disorder, and the use of cannabinoids for medicinal purposes. The content evaluation through the Health Education Content Validation Instrument concluded that the tool was considered to have a good structure and content (Content Validity Index > 0,78; overall score = 9.0/10.0). The tool also proved to be functional and highly usable according to the analysis with the System Usability Scale (overall usability score = 9.2/10.0) . Digital strategies such as chatbots can help in health education and scientific communication within stigmatized areas, such as the consumption of psychoactive substances.

The stingless bee Frieseomelitta varia Lepeletier 1836 (Hymenoptera: Apidae) is an essential pollinator in natural and agricultural ecosystems in the Neotropical region. However, these bees may be exposed to pesticides during foraging, which can affect both individuals and their colonies. One example comes from the use of pyraclostrobin (a fungicide) and thiamethoxam (an insecticide) for pest control in pepper crops, which F. varia visits. This study aimed to evaluate the isolated and combined sublethal effects of thiamethoxam (TMX) (0.000543 ng a.i./µL) and pyraclostrobin (PYR) (1.5 ng i.a./µL) on the morphology of the midgut and Malpighian tubules of F. varia workers. Results showed that both pesticides, regardless of the exposure time (through feeding during 48 h or 96 h), disturbed the morphology of the analyzed organs. Specifically, F. varia exposed orally to sublethal concentrations of thiamethoxam and pyraclostrobin, either alone or in combination, exhibited a higher rate of damage to the midgut (e.g., vacuolization, apocrine secretion, and cellular elimination) compared to the bees in the control groups, both after 48 h and 96 h of exposure. In Malpighian tubules, vacuolation is the only damage present. As the observed morphological alterations likely compromise the excretion and absorption functions, exposure to pyraclostrobin and thiamethoxam may lead to disturbances at both the individual and colony levels. These results highlight the urgent need for a future reassessment of the safety of fungicides and insecticides regarding their potential effects on bee populations., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Stingless bees (Hymenoptera: Meliponini) are pollinators of both cultivated and wild crop plants in the Neotropical region. However, they are susceptible to pesticide exposure during foraging activities. The fungicide fluazinam is commonly applied in bean and sunflower cultivation during the flowering period, posing a potential risk to the stingless bee Partamona helleri, which serves as a pollinator for these crops. In this study, we investigated the impact of acute oral exposure (24 h) fluazinam on the survival, morphology and cell death signaling pathways in the midgut, oxidative stress and behavior of P. helleri worker bees. Worker bees were exposed for 24 h to fluazinam (field concentrations 0.5, 1.5 and 2.5 mg a.i. mL -1 ), diluted in 50 % honey aqueous solution. After oral exposure, fluazinam did not harm the survival of worker bees. However, sublethal effects were revealed using the highest concentration of fluazinam (2.5 mg a.i. mL -1 ), particularly a reduction in food consumption, damage in the midgut epithelium, characterized by degeneration of the brush border, an increase in the number and size of cytoplasm vacuoles, condensation of nuclear chromatin, and an increase in the release of cell fragments into the gut lumen. Bees exposed to fluazinam exhibited an increase in cells undergoing autophagy and apoptosis, indicating cell death in the midgut epithelium. Furthermore, the fungicide induced oxidative stress as evidenced by an increase in total antioxidant and catalase enzyme activities, along with a decrease in glutathione S-transferase activity. And finally, fluazinam altered the walking behavior of bees, which could potentially impede their foraging activities. In conclusion, our findings indicate that fluazinam at field concentrations is not lethal for workers P. helleri. Nevertheless, it has side effects on midgut integrity, oxidative stress and worker bee behavior, pointing to potential risks for this pollinator., Competing Interests: Declaration of Competing Interest The authors confirm that they have no conflicts of interest with respect to the work described in this manuscript., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Partamona helleri is an important pollinator in the Neotropics. However, this bee faces an increased risk of pesticide exposure, potentially affecting both individual bees and entire colonies. Thus, this study aimed to evaluate the effects of the herbicide tebuthiuron on behavior, antioxidant activity, midgut morphology, and signaling pathways related to cell death, cell proliferation and differentiation in P. helleri workers. tebuthiuron significantly reduced locomotor activity and induced morphological changes in the midgut. The activity of the detoxification enzymes superoxide dismutase and glutathione S-transferase increased after exposure, indicating a detoxification mechanism. Furthermore, the herbicide led to alterations in the number of positive cells for signaling-pathway proteins in the midgut of bees, suggesting induction of apoptotic cell death and disruption of midgut epithelial regeneration. Therefore, tebuthiuron may negatively impact the behavior, antioxidant activity, morphology, and physiology of P. helleri workers, potentially posing a threat to the survival of this non-target organism., 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 Elsevier B.V. All rights reserved.)

Purpose: This report presents the endovascular strategies adopted to treat a kidney calculus venous embolism after percutaneous nephrolithotomy and the versatility of endovascular techniques to manage even the most unexpected renovascular complications after urological intervention. According to the literature available in PubMed, Cochrane, SciELO, and Science.gov repositories, this is the first case to our knowledge of renal vein calculus embolism as a complication of percutaneous treatment of kidney stones., Case Report: A 62-year-old woman underwent percutaneous nephrolithotomy to treat a left kidney 2.8-cm staghorn calculi. The stone cracked, leaving a residual fragment in the ureteropelvic junction. Abdominal computed tomography revealed a 0.9-mm extrarenal calculus located inside the left retroaortic renal vein. Calculus was captured using a basket catheter system through a 6F 45-cm sheath positioned in the left common femoral vein (CFV) and accessed by dissection to safely conclude the calculus extraction by venous cut down. The patient was asymptomatically discharged 48 hours after the endovascular procedure, under a rivaroxaban anticoagulation regimen, with no symptoms or renal function impairment until the 6 months of follow-up., Conclusion: The endovascular strategy proposed in this case was effective for calculus rescue and venous flow restoration., Clinical Impact: This case reinforces the adaptability of endovascular therapy in an unexpected scenario. A potentially life-threatening extremely rare adverse event following a common urological procedure could be treated with minimally invasive hybrid treatment, preserving renal function and maintaining venous vascular patency. This report may add a discussion of procedures to manage similar events and bring to the literature a possible strategy to solve the problem., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The Aedes aegypti mosquito is a vector for various arboviruses, including dengue and yellow fever. Insecticides, such as pyrethroids and organophosphates, are widely used to manage and control these insects. However, mosquitoes have developed resistance to these chemicals. Therefore, this study aimed to investigate the effects of the commercial formulation of fipronil (Tuit® Florestal; 80% purity) on the survival, behavior, morphology, and proteins related to signaling pathways of the midgut in A. aegypti larvae under controlled laboratory conditions. Significant reductions in immature survival were observed in all concentrations of fipronil tested. Low insecticide concentration (0.5 ppb) led to decreased locomotor activity in the larvae and caused disorganization of the epithelial tissue in the midgut. Moreover, exposure to the insecticide decreased the activity of detoxifying enzymes such as catalase, superoxide dismutase, and glutathione-S-transferase. On the other hand, the insecticide increased protein oxidation and nitric oxide levels. The detection of LC3, caspase-3, and JNK proteins, related to autophagy and apoptosis, increased after exposure. However, there was a decrease in the positive cells for ERK 1/2. Furthermore, the treatment with fipronil decreased the number of positive cells for the proteins FMRF, Prospero, PH3, Wg, Armadillo, Notch, and Delta, which are related to cell proliferation and differentiation. These findings demonstrate that even at low concentrations, fipronil exerts larvicidal effects on A. aegypti by affecting behavior and enzymatic detoxification, inducing protein oxidation, free radical generation, midgut damage and cell death, and inhibiting cell proliferation and differentiation. Thus, this insecticide may represent a viable alternative for controlling the spread of this vector., 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 Elsevier Ltd. All rights reserved.)

The stingless bee Melipona scutellaris performs buzz pollination, effectively pollinating several wild plants and crops with economic relevance. However, most research has focused on honeybees, leaving a significant gap in studies concerning native species, particularly regarding the impacts of pesticide combinations on these pollinators. Thus, this study aimed to evaluate the sublethal effects of imidacloprid (IMD), pyraclostrobin (PYR), and glyphosate (GLY) on the behavior and fat body cell morphology and physiology of M. scutellaris. Foragers were orally exposed to the different pesticides alone and in combination for 48 h. Bees fed with contaminated solution walked less, moved slower, presented morphological changes in the fat body, including vacuolization, altered cell shape and nuclei morphology, and exhibited a higher count of altered oenocytes and trophocytes. In all exposed groups, alone and in combination, the number of cells expressing caspase-3 increased, but the TLR4 number of cells expressing decreased compared to the control groups. The intensity of HSP70 immunolabeling increased compared to the control groups. However, the intensity of the immunolabeling of HSP90 decreased in the IMD, GLY, and I + G (IMD + GLY) groups but increased in I + P-exposed bees (IMD + PYR). Alternatively, exposure to PYR and P + G (PYR + GLY) did not affect the immunolabeling intensity. Our findings demonstrate the hazardous effects and environmental consequences of isolated and combined pesticides on a vital neotropical pollinator. Understanding how pesticides impact the fat body can provide crucial insights into the overall health and survival of native bee populations, which can help develop more environmentally friendly approaches to agricultural practices., 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 Elsevier Ltd. All rights reserved.)

Rendu-Osler-Weber syndrome, also known as hereditary hemorrhagic telangiectasia, is an autosomal dominant hereditary disorder. It is characterized by presence of multiple arteriovenous malformations (AVMs) and telangiectasias. This article reports two cases of patients with Rendu-Osler-Weber syndrome who had pulmonary AVMs and underwent successful endovascular treatment. A brief review of the literature shows that up to 50% of patients with the syndrome have pulmonary AVMs and there is usually a positive family history in these patients. These pulmonary AVMs are multiple in 30% of cases and are associated with the most severe disease complications. Most patients are asymptomatic, even in the presence of AVMs with right-left shunts. When these shunts exceed 25% of the total blood volume, dyspnea, cyanosis, digital clubbing, and extracardiac murmurs may occur. Endovascular treatment is safe and offers control of complications from hereditary hemorrhagic telangiectasia and is currently the treatment of choice for these lesions., Competing Interests: Conflicts of interest: No conflicts of interest declared concerning the publication of this article., (Copyright© 2024 The authors.)

Pesticide use in agriculture threatens non-target insects such as bees. Considering the ecological and economic relevance of native bees, such as Scaptotrigona postica, and the insufficient studies on the effects of pesticides on their behavior and physiology, improving the current knowledge on this issue is essential. Therefore, this study investigated the sublethal effects of imidacloprid, pyraclostrobin, and glyphosate on the behavior and fat body cells of S. postica. Pesticide ingestion decreased the walking distance and mean velocity of bees compared to the control and solvent control groups. The oenocytes of the control groups were spherical, with central nuclei containing decondensed chromatin, and the trophocytes presented irregular morphology, with cells varying in shape and the cytoplasm filled with vacuoles and granules. However, bees exposed to pesticides showed extensive cytoarchitectural disruption in the fat body, such as vacuolization and shape changes in oenocytes and altered nuclei morphology in trophocytes. Moreover, pesticide exposure increased the number of atypical oenocytes and altered trophocytes, except for the PYR group, which showed a lower number of atypical oenocytes. Caspase-positive labeling significantly increased in all exposed bee groups. Alternatively, TLR4 labeling was significantly decreased in the exposed groups compared to the control groups. There was a significant increase in HSP90 immunolabeling in all exposed groups compared to the control. These findings reinforce the importance of research on the sublethal effects of low pesticide concentrations on key neotropical pollinators and prove that these toxic substances can impair their detoxification and immune defense., 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 © 2023 Elsevier B.V. All rights reserved.)

Several studies have investigated the consequences of exposure to neonicotinoids in honeybees. Given the lack of studies concerning the consequences of exposure of social wasps to neonicotinoids, as well as the ecological importance of these insects, the objective of this study was to test the hypothesis that chronic exposure to sublethal concentrations of thiamethoxam decreases survival and mobility by causing damage to the brain and midgut of the social wasp Polybia paulista. The wasps were exposed to different concentrations of thiamethoxam, in order to obtain the mean lethal concentration (LC 50 ), which was used as a reference for calculation of two sublethal concentrations (LC 50/100 and LC 50/10 ) employed in subsequent experiments. To calculate survival, groups of exposed (EW) and unexposed (UW) wasps were monitored until death, allowing calculation of the average lethal time. The EW and UW groups were evaluated after 12, 24, 48, and 72 h of exposure, considering their mobility and histopathological parameters of the midgut and brain. A lesion index based on semiquantitative analyses was used for comparison of histopathological damage. The results demonstrated that exposure to the LC 50/10 led to a significantly shorter survival time of the P. paulista workers, compared to unexposed wasps. In addition, both sublethal concentrations decreased mobility and caused damage to the intestine (loss of brush border, presence of spherocrystals, loss of cytoplasmic material, and pyknosis) and the brain (loss of cell contact and pyknosis), regardless of the exposure time. The findings showed that, like bees, social wasps are nontarget insects susceptible to the detrimental consequences of neonicotinoid use, with exposure leading to impaired survival, locomotion, and physiology., 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 © 2023 Elsevier B.V. All rights reserved.)

Objectives: This study describes an alternative carotid bifurcation endarterectomy technique in which the external carotid artery is used as a suture patch., Methods: Charts of ten patients with atherosclerotic carotid stenosis that were treated using the neobulb technique between 2002 and 2019 were reviewed., Results: No major surgical adverse event was observed in the postoperative assessments. No postoperative common or internal carotid stenosis was observed in the mid- or long-term follow-up., Conclusions: The neobulb technique allows carotid endarterectomy closure without a synthetic or venous patch, using the external carotid artery as an autologous patch, while preserving distal flow into the external carotid artery branches.

Fipronil has been widely used in agriculture and forestry in Brazil to control several pests. However, this insecticide may be hazardous to non-target organisms, including stingless bees, which are essential pollinators of crops and natural environments. Here, we investigated the effect of 24-h acute oral exposure to LC 50 of fipronil on the Malpighian tubules of the stingless bee Partamona helleri (Friese). Insecticide exposure decreases the respiration rate of forager bees, and the Malpighian tubules are severely affected, as shown by the epithelial architecture disorganization, loss of cytoplasmic content, degradation of the brush border, and nuclear pyknosis. In addition, fipronil ingestion increases the number of Malpighian cells positive for peroxidase, LC3, cleaved caspase-3, and JNK. However, Notch and ERK1/2-positive cells decrease in the exposed bees. These changes in the signaling proteins indicate an increase in oxidative stress, autophagy and apoptosis, and impairment of cell recovery. Overall, our results demonstrate the toxicological effects of fipronil on a stingless bee, which compromises the physiology of this important pollinator., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The global search for eco-friendly and human-safe pesticides has intensified, and research on essential oils (EOs) has expanded due to their remarkable insecticidal activities and apparent human-safe. Despite this, most of the literature focuses on short-term and simplified efforts to understand lethal effects, with only a few comprehensive studies addressing sublethal exposures. To fill this shortcoming, we explore the lethal and sublethal effects of Pogostemon cablin (Lamiaceae) EO and an EO-based emulsion (18%) using the coffee berry borer Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae) as a model. First, we determine the toxicity of EO and EO-based emulsion using dose-mortality curves and lethal times. Second, we subjected adult females of H. hampei to sublethal doses to assess whether they affected their behavior, reproductive output, and histological features. Our findings reveal that patchoulol (43.05%), α-Guaiene (16.06%), and α-Bulnesene (13.69%) were the main components of the EO. Furthermore, the EO and its emulsion had similar toxicity, with dose-mortality curves and lethal times overlapping 95% confidence intervals. We also observed that sublethal exposure of females of H. hampei reduces reproduction and feeding, increases walking activity, and causes histopathological changes in the midgut. This study advances the knowledge of the lethal and sublethal effects of an eco-friendly substance on insects.Responsible Editor: Giovanni Benelli., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

With the expansion of coronavirus in the World, the search for technology solutions based on the analysis and prospecting of diseases has become constant. The paper addresses a machine learning algorithms analysis used to predict and identify infected patients. For analysis, we use a multicriteria approach using the PROMETHEE-GAIA method, providing the structuring of alternatives respective to a set of criteria, thus enabling the obtaining of their importance degree under the perspective of multiple criteria. The study approaches a sensitivity analysis, evaluating the alternatives using the PROMETHEE I and II methods, along with the GAIA plan, both implemented by the Visual PROMETHEE computational tool, exploring numerical and graphical resources. The analysis model proves to be effective, guaranteeing the ranking of alternatives by inter criterion evaluation and local results with intra criterion evaluation, providing a transparent analysis concerning the selection of prediction algorithms to combat the COVID-19 pandemic., (© 2022 The Author(s). Published by Elsevier B.V.)

The pandemic caused by the new coronavirus has brought to light a series of concerns for the Brazilian population and government departments due to the different costly consequences that it has generated. It has also mobilized different strategic fronts that plan and implement several mitigating measures against the virus. Besides, the search for solutions for adequate care for individuals in need of support has been constant. This work uses ELECTRE-MOr, a Multi-Criteria Decision Aid (MCDA) method, to support the logistic plan for the vaccine distribution throughout Brazil, essentially to remote areas. The method allows an objective and structured classification of ideal types of thermal boxes for the storage of immunobiological inside the Cold Chain, presenting the best alternative that maintains the quality of materials until the final destination and has the best cost-benefit. Currently, the ELECTRE-MOr model is under development in a computational tool in Python, allowing the use of the method intuitively and clearly, enabling professionals of any area of expertise to apply it., (© 2022 The Author(s). Published by Elsevier B.V.)

Aedes aegypti is a vector of several global human viruses responsible for high human morbidity and mortality. The method to prevent the transmission of vector-borne viruses is mainly based on the control of the insect vector using insecticides. Among these chemicals, copper sulfate is a compound widely used in agriculture with the potential to be used as an alternative to control these insects. This study evaluated the effects of the exposure of A. aegypti larvae to copper sulfate on survival, midgut morphology, blood-feeding and fecundity. The exposure to CuSO 4 decreased the survival of A. aegypti during the immature phase. Adults obtained from exposed larvae had their lifespan decreased at all tested concentrations. The exposure to CuSO 4 impaired the development in the transition from larvae to pupae and from pupae to adult. The number of eggs laid by females developed from larvae treated with CuSO 4 was significantly lower than in control. In addition, the egg hatching rates were also negatively affected. The midguts of treated larvae and pupae showed epithelial disorganization. The number of cleaved caspase-3 cells increased in the midgut of exposed pupae compared to control. Moreover, there was a reduction in proliferating cells in treated larvae and pupae compared to the control. In conclusion, the results reveal that CuSO 4 exposure has insecticidal activity against A. aegypti, which may be related to the impairment of the midgut metamorphosis and reduced proliferation of stem cells, with the consequent impairment of female mosquito fertility and fecundity., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Fipronil is a pesticide widely used to control agricultural and household insect pests. However, fipronil is highly toxic to non-target insects, including pollinators. In this study, we investigated the acute effects of fipronil on the behavior, brain morphology, antioxidant activity, and proteins related to signaling pathways on the brain of workers of the stingless bee Partamona helleri. The ingestion of fipronil increases both the walking distance and velocity and causes enlarged intercellular spaces in the Kenyon cells and intense vacuolization in the neuropils of the brain. Moreover, fipronil decreases the activity of catalase (CAT) and increases the activity of glutathione S-transferase (GST). However, there is no difference in superoxide dismutase (SOD) activity between the control and fipronil. Regarding immunofluorescence analysis, bees exposed to fipronil showed an increase in the number of cells positive for cleaved caspase-3 and peroxidase, but a reduction in the number of cells positive for ERK 1/2, JNK and Notch, suggesting neuron death and impaired brain function. Our results demonstrate that fipronil has harmful effects on the behavior and brain of a stingless bee, which may threaten the individuals and colonies of this pollinator., 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 © 2021 Elsevier B.V. All rights reserved.)

Umbilical cord blood (UCB) has long been seen as a rich source of naïve cells with strong regenerative potential, likely mediated by paracrine signals. More recently, small extracellular vesicles (sEV), such as exosomes, have been shown to play essential roles in cell-to-cell communication, via the transport of numerous molecules, including small RNAs. Often explored for their potential as biomarkers, sEV are now known to have regenerative and immunomodulating characteristics, particularly if isolated from stem cell-rich tissues. In this study, we aim to characterize the immunomodulating properties of umbilical cord blood mononuclear cell-derived sEV (UCB-MNC-sEV) and explore their therapeutic potential for inflammatory skin diseases. UCB-MNC-sEV were shown to shift macrophages toward an anti-inflammatory phenotype, which in turn exert paracrine effects on fibroblasts, despite previous inflammatory stimuli. Additionally, the incubation of PBMC with UCB-MNC-sEV resulted in a reduction of total CD4 + and CD8 + T-cell proliferation and cytokine release, while specifically supporting the development of regulatory T-cells (Treg), by influencing FOXP3 expression. In a 3D model of psoriatic skin, UCB-MNC-sEV reduced the expression of inflammatory and psoriatic markers IL6 , IL8 , CXCL10 , COX2 , S100A7 , and DEFB4 . In vivo, UCB-MNC-sEV significantly prevented or reversed acanthosis in imiquimod-induced psoriasis, and tendentially increased the number of Treg in skin, without having an overall impact on disease burden. This work provides evidence for the anti-inflammatory and tolerogenic effect of UCB-MNC-sEV, which may be harnessed for the treatment of Th17-driven inflammatory skin diseases, such as psoriasis.

The development and adoption of cell therapies has been largely limited by difficulties associated with their safety, handling, and storage. Extracellular vesicles (EV) have recently emerged as a likely mediator for the therapeutic effect of cells, offering several advantages over cell therapies. Due to their small size and inability to expand and metastasize, EV are generally considered safer than cell transplantation. Nevertheless, few studies have scrutinized the toxicity profile of EV, particularly after repeated high-dose administration. The present study aimed to evaluate a preparation of small EV obtained from umbilical cord blood mononuclear cells (UCB-MNC-sEV) for its cytotoxicity in different cell lines, as well as its differential accumulation, distribution, and toxicity following repeated intravenous (IV) administrations in a rodent model. In vitro, repeated sEV exposure in concentrations up to 1 × 10 11 particles/mL had no deleterious impact on the viability or metabolic activity of peripheral blood mononuclear cells, THP-1 monocytes, THP-1-derived macrophages, normal dermal human fibroblasts, or human umbilical vein endothelial cells. DiR-labelled sEV, injected intravenously for four weeks in healthy rats, were detected in clearance organs, particularly the kidneys, spleen, and liver, similarly to control dye. Moreover, repeated administrations for six and twelve weeks of up to 1 × 10 10 total particles of sEV dye were well-tolerated, with no changes in general haematological cell counts, or kidney and liver toxicity markers. More importantly, unlabelled sEV likewise did not induce significant alterations in cellular and biochemical blood parameters, nor any morphological changes in the heart, kidney, lung, spleen, or liver tissue. In sum, our data show that UCB-MNC-sEV have no significant toxicity in vitro or in vivo, even when administered repeatedly at high concentrations, therefore confirming their safety profile and potential suitability for future clinical use.

Partamona helleri is an important pollinator in natural and agricultural ecosystems in the neotropics. However, the foraging activity of this bee increases its risk of exposure to pesticides, which may affect both the individuals and the colony. Thus, this study aims to evaluate the side effects of LC 50 of fipronil (0.28 ng a.i. μL -1 ) on the midgut morphology, antioxidant activity and some pathways of cell death, proliferation and differentiation in workers of P. helleri, after 24 h of oral exposure. Fipronil caused morphological alterations in the midgut of the bees. The activities of the detoxification enzymes superoxide dismutase, catalase and glutathione S-transferase increased after exposure, which suggests the occurrence of a detoxification mechanism. Furthermore, exposure to fipronil changed the number of positive cells for signaling-pathway proteins in the midgut of bees, which indicates the induction of cell death by the apoptotic pathway and impairment of the midgut epithelial regeneration. These results demonstrate that fipronil may negatively affect the morphology and physiology of the midgut of the stingless bee P. helleri and impose a threat to the survival of non-target organisms., 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 © 2021 Elsevier B.V. All rights reserved.)

Extracellular vesicles (EV) are a promising therapeutic tool in regenerative medicine. These particles were shown to accelerate wound healing, through delivery of regenerative mediators, such as microRNAs. Herein we describe an optimized and upscalable process for the isolation of EV smaller than 200 nm (sEV), secreted by umbilical cord blood mononuclear cells (UCB-MNC) under ischemic conditions and propose quality control thresholds for the isolated vesicles, based on the thorough characterization of their protein, lipid and RNA content. Ultrafiltration and size exclusion chromatography (UF/SEC) optimized methodology proved superior to traditional ultracentrifugation (UC), regarding production time, standardization, scalability, and vesicle yield. Using UF/SEC, we were able to recover approximately 400 times more sEV per mL of media than with UC, and upscaling this process further increases EV yield by about 3-fold. UF/SEC-isolated sEV display many of the sEV/exosomes classical markers and are enriched in molecules with anti-inflammatory and regenerative capacity, such as hemopexin and miR-150. Accordingly, treatment with sEV promotes angiogenesis and extracellular matrix remodeling, in vitro. In vivo, UCB-MNC-sEV significantly accelerate skin regeneration in a mouse model of delayed wound healing. The proposed isolation protocol constitutes a significant improvement compared to UC, the gold-standard in the field. Isolated sEV maintain their regenerative properties, whereas downstream contaminants are minimized. The use of UF/SEC allows for the standardization and upscalability required for mass production of sEV to be used in a clinical setting., (© 2021 The Authors. STEM CELLS TRANSLATIONAL MEDICINE published by Wiley Periodicals LLC on behalf of AlphaMed Press.)

Purpose: Obesity and high-fat (HF) diet are associated with over activation of the endocannabinoid system (ECS). We have demonstrated that maternal HF diet induces early obesity and modulates cannabinoid signaling in visceral (VIS) and subcutaneous (SUB) white adipose tissue (WAT) in weanling rat offspring. We hypothesized that perinatal maternal HF diet would program the expression of ECS in adipose tissue in a long-term way in parallel to alterations in epigenetic markers and sex hormone signaling., Methods: Progenitor female rats received control diet (C, 9% fat) or isocaloric high-fat diet (HF, 28% fat) for 8 weeks before mating, gestation, and lactation. All pups were weaned to C diet and they were euthanized at 180 days old., Results: Maternal HF diet induced overweight and increased SUB WAT mass of male and female adult offspring. Maternal HF diet induced hypertrophy of VIS and SUB adipocytes only in female offspring associated with increased type 1 cannabinoid receptor protein (CB1) and mRNA (Cnr1) levels. These changes were associated with increased estrogen receptor α binding to Cnr1 promoter in SUB WAT of adult female offspring, which may contribute to higher expression of Cnr1., Conclusion: Increased CB1 signaling in adipose tissue might contribute to higher adiposity programmed by maternal HF diet because endocannabinoids stimulate the accumulation of fat in the adipose tissue. Our findings provide molecular insights into sex-specific targets for anti-obesity therapies based on the endocannabinoid system.

This article aims to draw an overview on the actual knowledge on bacteriostatic and bactericidal natural clays. Particular emphasis is given to the role of clay itself, the action of reduced metals located either in the structure of clay minerals or external to them as constituents of associate minerals, and the definition of the mechanisms of action based on the achievements found in all available studies being carried out so far. The term bactericidal is herein used when a clay or a clay mineral kill the bacteria, whereas the term bacteriostatic is used when those minerals stop bacteria growth and replication. The second part of this article deals with experimental studies on bactericidal natural clay, experience and perspective for the preparation of bactericidal natural clays, interesting on the authors perspective and experience for the preparation of pathogens safe both therapeutic and cosmetic natural mud/natural peloid, and better yet of both therapeutic 87oooand cosmetic peloid itself and designed and engineered peloid. The authors also show how to convert non-antimicrobial clay into antimicrobial one, opening the way in the field of pelotherapy to the preparation of sanitary safe peloids addressed, for instance, to the treatment of rheumatic disabilities, as well as to the preparation of antimicrobial peloids and, in particular, of dermatological ointments, all able to fight infectious skin disorders.

Treatment strategies for inflammatory bowel disease (IBD) focus on the induction and long-term maintenance of deep remission to avoid complications of active disease and improve long-term outcomes. Medical therapies for IBD, notably the increasingly widespread use of biological therapy, are often effective at controlling disease, but these drugs are associated with substantial adverse events, which together with other factors-including increasing treatment costs and patient preferences-leads to concerns regarding indefinite use of medical therapy. Consequently, the need to consider the safety and feasibility of drug de-escalation once IBD remission has been achieved is clear. Here, we review the current evidence surrounding de-escalation of immunomodulator and biological therapy in Crohn's disease and ulcerative colitis. We discuss strategies for de-escalation, including the selection of patients who are appropriate for treatment de-escalation and the use of proactive drug monitoring, and review the evidence on subsequent optimal follow-up. We conclude by proposing an algorithm to guide de-escalation decisions, and highlight future perspectives, including the potential effect of emerging medication and personalised medicine for these diseases., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Maternal nutritional imbalances trigger developmental adaptations involving early epigenetic mechanisms associated with adult chronic disease. Maternal high-fat (HF) diet promotes obesity and hypothalamic leptin resistance in male rat offspring at weaning and adulthood. Leptin resistance is associated with over activation of the endocannabinoid system (ECS). The ECS mainly consists of endocannabinoids derived from n-6 fatty acids and cannabinoid receptors (CB1 coded by Cnr1 and CB2 coded by Cnr2). The CB1 activation in hypothalamus stimulates feeding and appetite for fat while CB2 activation seems to play an immunomodulatory role. We demonstrated that maternal HF diet increases hypothalamic CB1 in male offspring while increases CB2 in female offspring at birth, prior to obesity development. However, the molecular mechanisms behind these changes remain unexplored. We hypothesized that maternal HF diet would down-regulate leptin signaling and up-regulate Cnr1 mRNA levels in the hypothalamus of the offspring at birth, associated with sex-specific changes in epigenetic markers and sex steroid signaling. To test our hypothesis, we used progenitor female rats that received control diet (C, 9% fat) or isocaloric high-fat diet (HF, 28% fat) from 8 weeks before mating until delivery. Blood, hypothalamus and carcass from C and HF male and female offspring were collected for biochemical and molecular analyses at birth. Maternal HF diet down-regulated the transcriptional factor STAT3 in the hypothalamus of male and female offspring, but induced hypoleptinemia only in males and decreased phosphorylated STAT3 only in female offspring. Because leptin acts through STAT3 pathway to inhibit central ECS, our results suggest that leptin pathway impairment might contribute to increased levels of Crn1 mRNA in hypothalamus of both sex offspring. Besides, maternal HF diet increased the histone acetylation percentage of Cnr1 promoter in male offspring and increased the androgen receptor binding to the Cnr1 promoter, which can contribute to higher expression of Cnr1 in newborn HF offspring. Maternal HF diet increased plasma n6 to n3 fatty acid ratio in male offspring, which is an important risk factor to metabolic diseases and might indicate an over activation of endocannabinoid signaling. Thus, although maternal HF diet programs a similar phenotype in adult offspring of both sexes (obesity, hyperphagia and higher preference for fat), here we showed that molecular mechanisms involving leptin signaling, ECS, epigenetic markers and sex hormone signaling were modified prior to obesity development and can differ between newborn male and female offspring. These observations may provide molecular insights into sex-specific targets for anti-obesity therapies., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Eibesfeldtphora tonhascai (Diptera: Phoridae) is a parasitoid of leaf-cutting ants and a potential biological control agent against these insect pests. This study describes the morphology of the ovary and spermatheca of E. tonhascai. The female reproductive tract of this parasitoid has a pair of meroistic polytrophic ovaries, two lateral oviducts that open into a common oviduct, an elongated accessory gland, and two spermathecae. Young oocytes are small and spherical, and their size increases as yolk is stored in the cytoplasm. This process is followed by chorion production by follicular cells. Mature oocytes are elliptical or torpedo-shaped. The reservoir wall of the spermatheca has type III glandular cells with cytoplasm rich in free ribosomes, rough endoplasmic reticulum, and secretory vesicles. The apical surface of these cells has microvilli associated with mitochondria. The reservoir lumen is lined by a cuticle and filled with spermatozoa. This is the first report of the ovary and spermatheca morphology of E. tonhascai and contributes to the comprehension of the reproductive biology of this parasitoid of leaf-cutting ants.

Atta bisphaerica (Forel) is a leaf-cutting ant that specializes on grass and causes productivity losses in sugar cane fields and pastures. Three phorid species, Apocephalus attophilus (Borgmeier), Myrmosicarius grandicornis (Borgmeier) and Eibesfeldtphora bragancai (Brown), have been found parasitizing A. bisphaerica workers. These parasitoids can reduce plant material transported into the nests and ant traffic on the trails. Therefore, phorid flies have been considered potential biological control agents for leaf-cutting ants. Here, we evaluated which parasitoid species attack the leaf-cutting ant A. bisphaerica in pasture areas of a Brazilian Savannah-Atlantic Forest ecotone, parasitism rate, effect of host size, sexual dimorphism and sex ratio of the emerged parasitoids. Four nests of A. bisphaerica were selected in pasture areas from August 2016 to August 2017, with 400 workers collected from each colony monthly. A total of 23,714 A. bisphaerica workers were collected during the study, of which 236 (0.99%) were parasitized by phorid parasitoids. Apocephalus attophilus, E. bragancai and M. grandicornis parasitized 217, 17 and 2 ants, respectively. The higher parasitism rate was found in the hottest/rainy season of the year. Non-parasitized ants survived longer than those parasitized by A. attophilus. The larval and pupal periods of this parasitoid were 2.2 ± 0.8 and 16 ± 1.4 days, respectively, and the number of pupae per parasitized ant ranged from 1 to 7. The number of A. attophilus pupae per host increased with the host head size. Likewise, the size of the adult parasitoids also increased according to the host ant. Apocephalus attophilus females were larger than males and the sex ratio (male: female) did not differ from 1: 1. Our results showed that A. attophilus would be a potential biocontrol agent of leaf-cutting ants because it produces multiple larvae per host, allowing a great production of parasitoids with short developmental time and kills the host ant faster than other phorids., Competing Interests: The authors have declared that no competing interests exist.

Pregnancy is characterized by numerous physiological changes that may lead to a diversity of symptoms and frequently to gastrointestinal complaints, such as heartburn, nausea and vomiting, or constipation. Chronic gastrointestinal diseases require treatment maintenance during this period, raising the challenging question whether outcomes beneficial to the mother may be harmful for the fetus. In addition, certain diseases, such as acute fatty liver of pregnancy, only develop during pregnancy and may require urgent procedures, such as fetus delivery. Even though they are not present in our day-to-day practice, knowledge of pregnancy-related diseases is fundamental and collaboration between gastroenterologists and obstetricians is often necessary. Herein, we review pregnancy-related diseases and systematize the most appropriate treatment choices according to the recent literature and guidelines, so that the article can serve as a guide to the gastroenterologist regarding the medical approach to pregnancy-related gastrointestinal and liver diseases and their therapeutic management., Competing Interests: Conflict of Interest: None

The leaf-cutting ant Atta sexdens Forel (Hymenoptera: Formicidae) is one of the most damaging agricultural pests in the Neotropics. Management strategies predominantly rely on the use of general insecticides. What is needed are more species-specific and environmentally friendly options. Parasitioids such as phorid flies (Diptera: Phoridae) may be one such option, but a greater understanding of the ecology of the flies and their ant hosts is essential to devise biological control strategies. Here we report parasitism rates, ant host size, parasitoid abundance per host and resultant sex ratios of two phorid species Apocephalus attophilus Borgmeier and Eibesfeldtphora tonhascai Brown parasitizing A.sexdens. The two species achieved parasitism rates of 1.48 and 1.46%, respectively and the pupal period was 14.7 ± 1.1 days and 22.1 ± 2.8 days, respectively. There was no significant difference between the head capsule width of ants parasitized by either A. attophilus or E. tonhascai. Likewise, there was no significant effect between the head capsule width of parasitized and unparasitized ants for both species. A significant positive correlation was found between the head capsule width of the parasitized ants and the number of adult parasitoids A. attophilus emerged. Ants parasitized by E. tonhascai survived significantly longer than those parasitized by A. attophilus. There was no significant effect of ant head width on the sex ratio of the offspring of either parasitoid species and no significant difference in the sex ratio (male: female) of their offspring. In summary, these data addressed here are important steps when considering natural enemies for biological control. Studying survival of the parasitized ants, parasitoid offspring sex ratio and host size preference allows for a better understanding of ant natural biological control in the field and can help in rearing of A. attophilus and E. tonhascai in laboratory.

Dopamine can modulate long-term episodic memory. Its potential role on the generation of false memories, however, is less well known. In a randomized, double-blind, placebo-controlled experiment, 24 young healthy volunteers ingested a 4-mg oral dose of haloperidol, a dopamine D 2 -receptor antagonist, or placebo, before taking part in a recognition memory task. Haloperidol was active during both study and test phases of the experiment. Participants in the haloperidol group produced more false recognition responses than those in the placebo group, despite similar levels of correct recognition. These findings show that dopamine blockade in healthy volunteers can specifically increase false recognition memory., (Copyright © 2016 John Wiley & Sons, Ltd.)

Introduction: A tight balance between regulatory CD4 + Foxp3 + (Treg) and conventional CD4 + Foxp3 - (Tconv) T cell subsets in the peripheral compartment, maintained stable throughout most of lifetime, is essential for preserving self-tolerance along with efficient immune responses. An excess of Treg cells, described for aged individuals, may critically contribute to their reported immunodeficiency. In this work, we investigated if quantitative changes in thymus emigration may alter the Treg/Tconv homeostasis regardless of the aging status of the peripheral compartment., Methods: We used two different protocols to modify the rate of thymus emigration: thymectomy of adult young (4-6 weeks old) mice and grafting of young thymus onto aged (18 months old) hosts. Additionally, lymphoid cells from young and aged B6 mice were intravenously transferred to B6. RAG2 -/- mice. Alterations in Treg and Tconv peripheral frequencies following these protocols were investigated after 30 days by flow cytometry., Results: Thymectomized young mice presented a progressive increase in the Treg cell frequency, while the grafting of a functional thymus in aged mice restored the young-like physiological Treg/Tconv proportion. Strikingly, T cells derived from young or aged splenocytes colonized the lymphopenic periphery of RAG -/- hosts to the same extent, giving rise to similarly elevated Treg cell levels irrespective of the age of the donor population. In the absence of thymus output, the Treg subset seems to survive longer, as confirmed by their lower proportion of Annexin-V + cells., Conclusions: Our data suggest that the thymus-emigrating population, harboring an adequate proportion of Treg/Tconv lymphocytes, may be essential to keep the Treg cell balance, independently of age-related shifts intrinsic to the peripheral environment or to the T cell biology.