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1.
Commun Biol ; 7(1): 687, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839829

RESUMO

Understanding the factors influencing mosquitoes' fecundity and longevity is important for designing better and more sustainable vector control strategies, as these parameters can impact their vectorial capacity. Here, we address how mating affects midgut growth in Aedes aegypti, what role Juvenile Hormone (JH) plays in this process, and how it impacts the mosquito's immune response and microbiota. Our findings reveal that mating and JH induce midgut growth. Additionally, the establishment of a native bacterial population in the midgut due to JH-dependent suppression of the immune response has important reproductive outcomes. Specific downregulation of AMPs with an increase in bacteria abundance in the gut results in increased egg counts and longer lifespans. Overall, these findings provide evidence of a cross-talk between JH response, gut epithelial tissue, cell cycle regulation, and the mechanisms governing the trade-offs between nutrition, immunity, and reproduction at the cellular level in the mosquito gut.


Assuntos
Aedes , Fertilidade , Microbioma Gastrointestinal , Hormônios Juvenis , Animais , Aedes/microbiologia , Aedes/crescimento & desenvolvimento , Aedes/fisiologia , Hormônios Juvenis/metabolismo , Feminino , Aptidão Genética
2.
Curr Opin Insect Sci ; 63: 101203, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705385

RESUMO

Vector-borne diseases are globally prevalent and represent a major socioeconomic problem worldwide. Blood-sucking arthropods transmit most pathogenic agents that cause these human infections. The pathogens transmission to their vertebrate hosts depends on how efficiently they infect their vector, which is particularly impacted by the microbiota residing in the intestinal lumen, as well as its cells or internal organs such as ovaries. The balance between costs and benefits provided by these interactions ultimately determines the outcome of the relationship. Here, we will explore aspects concerning the nature of microbe-vector interactions, including the adaptive traits required for their establishment, the varied outcomes of symbiotic interactions, as well as the factors influencing the transition of these relationships across a continuum from parasitism to mutualism.


Assuntos
Vetores Artrópodes , Simbiose , Animais , Vetores Artrópodes/microbiologia , Vetores Artrópodes/parasitologia , Insetos Vetores/microbiologia , Insetos Vetores/fisiologia , Doenças Transmitidas por Vetores/transmissão
3.
FASEB J ; 38(10): e23691, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38780525

RESUMO

Heme is a prosthetic group of proteins involved in vital physiological processes. It participates, for example, in redox reactions crucial for cell metabolism due to the variable oxidation state of its central iron atom. However, excessive heme can be cytotoxic due to its prooxidant properties. Therefore, the control of intracellular heme levels ensures the survival of organisms, especially those that deal with high concentrations of heme during their lives, such as hematophagous insects. The export of heme initially attributed to the feline leukemia virus C receptor (FLVCR) has recently been called into question, following the discovery of choline uptake by the same receptor in mammals. Here, we found that RpFLVCR is a heme exporter in the midgut of the hematophagous insect Rhodnius prolixus, a vector for Chagas disease. Silencing RpFLVCR decreased hemolymphatic heme levels and increased the levels of intracellular dicysteinyl-biliverdin, indicating heme retention inside midgut cells. FLVCR silencing led to increased expression of heme oxygenase (HO), ferritin, and mitoferrin mRNAs while downregulating the iron importers Malvolio 1 and 2. In contrast, HO gene silencing increased FLVCR and Malvolio expression and downregulated ferritin, revealing crosstalk between heme degradation/export and iron transport/storage pathways. Furthermore, RpFLVCR silencing strongly increased oxidant production and lipid peroxidation, reduced cytochrome c oxidase activity, and activated mitochondrial biogenesis, effects not observed in RpHO-silenced insects. These data support FLVCR function as a heme exporter, playing a pivotal role in heme/iron metabolism and maintenance of redox balance, especially in an organism adapted to face extremely high concentrations of heme.


Assuntos
Heme , Mitocôndrias , Oxirredução , Rhodnius , Animais , Heme/metabolismo , Rhodnius/metabolismo , Mitocôndrias/metabolismo , Receptores Virais/metabolismo , Receptores Virais/genética , Vírus da Leucemia Felina/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética
4.
J Biol Chem ; 300(6): 107272, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38588812

RESUMO

Wolbachia pipientis is a maternally transmitted symbiotic bacterium that mainly colonizes arthropods, potentially affecting different aspects of the host's physiology, e.g., reproduction, immunity, and metabolism. It has been shown that Wolbachia modulates glycogen metabolism in mosquito Aedes fluviatilis (Ae. fluviatilis). Glycogen synthesis is controlled by the enzyme GSK3, which is also involved in immune responses in both vertebrate and invertebrate organisms. Here we investigated the mechanisms behind immune changes mediated by glycogen synthase kinase ß (GSK3ß) in the symbiosis between Ae. fluviatilis and W. pipientis using a GSK3ß inhibitor or RNAi-mediated gene silencing. GSK3ß inhibition or knockdown increased glycogen content and Wolbachia population, together with a reduction in Relish2 and gambicin transcripts. Furthermore, knockdown of Relish2 or Caspar revealed that the immunodeficiency pathway acts to control Wolbachia numbers in the host. In conclusion, we describe for the first time the involvement of GSK3ß in Ae. fluviatilis immune response, acting to control the Wolbachia endosymbiotic population.


Assuntos
Aedes , Simbiose , Wolbachia , Wolbachia/fisiologia , Wolbachia/metabolismo , Aedes/microbiologia , Aedes/imunologia , Aedes/metabolismo , Animais , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Glicogênio/metabolismo
5.
Parasit Vectors ; 17(1): 12, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184590

RESUMO

BACKGROUND: The high prevalence of metabolic syndrome in low- and middle-income countries is linked to an increase in Western diet consumption, characterized by a high intake of processed foods, which impacts the levels of blood sugar and lipids, hormones, and cytokines. Hematophagous insect vectors, such as the yellow fever mosquito Aedes aegypti, rely on blood meals for reproduction and development and are therefore exposed to the components of blood plasma. However, the impact of the alteration of blood composition due to malnutrition and metabolic conditions on mosquito biology remains understudied. METHODS: In this study, we investigated the impact of whole-blood alterations resulting from a Western-type diet on the biology of Ae. aegypti. We kept C57Bl6/J mice on a high-fat, high-sucrose (HFHS) diet for 20 weeks and followed biological parameters, including plasma insulin and lipid levels, insulin tolerance, and weight gain, to validate the development of metabolic syndrome. We further allowed Ae. aegypti mosquitoes to feed on mice and tracked how altered host blood composition modulated parameters of vector capacity. RESULTS: Our findings identified that HFHS-fed mice resulted in reduced mosquito longevity and increased fecundity upon mosquito feeding, which correlated with alteration in the gene expression profile of nutrient sensing and physiological and metabolic markers as studied up to several days after blood ingestion. CONCLUSIONS: Our study provides new insights into the overall effect of alterations of blood components on mosquito biology and its implications for the transmission of infectious diseases in conditions where the frequency of Western diet-induced metabolic syndromes is becoming more frequent. These findings highlight the importance of addressing metabolic health to further understand the spread of mosquito-borne illnesses in endemic areas.


Assuntos
Aedes , Insulinas , Síndrome Metabólica , Doenças dos Roedores , Animais , Camundongos , Longevidade , Aedes/genética , Dieta Ocidental , Mosquitos Vetores/genética , Fertilidade , Vertebrados , Expressão Gênica
6.
Int J Surg Case Rep ; 110: 108780, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37678033

RESUMO

INTRODUCTION AND IMPORTANCE: Traumatic abdominal wall hernia (TAWH) is an injury that occurs after an abdominal wall blunt trauma consisting of fasciomuscular rupture and does not present skin penetration. Documenting unique and rare clinical cases, such as traumatic hernia without skin penetration, enriches the medical literature and provides valuable information to identify innovative and optimised approaches for the treatment of similar cases in the future. CASE PRESENTATION: 48-year-old female with no significant medical history presented to the emergency room after being directly hit by a 1200 kg vehicle while standing in the street. Clinical examination revealed a TAWH with total elevation and total loss of insertion of all abdominal wall muscles on the right side, and no involvement of the overlying skin secondary to the mechanism of trauma. The patient agreed to surgical management after being thoroughly informed about the procedure. Surgical exploration was performed with the patient in a lateral position, and the incision was made over the hernia sac. A monopolar electrocautery was used to expose the iliac crest and fully visualize the defect before drilling through the iliac crest. Soft macroporous polypropylene mesh repair was guided through the iliac crest and abdominal wall using a suture and secured with knots. The patient showed a satisfactory and favorable progress. DISCUSSION AND CONCLUSIONS: The present surgical technique is recommended for atypical cases of high-strength TAWH.

7.
Curr Biol ; 33(16): R851-R852, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37607477

RESUMO

Global socio-ecological shocks, such as the COVID-19 pandemic, can threaten progress in protecting vulnerable marine environments by altering behaviour of resource users1. When government priorities shift from environmental protection towards safeguarding human populations, control of illegal activity in protected areas can alter. Resulting increases in illegal fishing in large-scale marine protected areas (MPAs) are of particular concern as they contain a large proportion of marine protected area globally2. Here, we report on average 19 times as many suspected illegal fishing vessels per month in 2022 (n = 19) compared with 2010 to 2020 (n = 1) in an Indian Ocean MPA. Although illegal fishing has been a pervasive problem, the current spike in Indian vessels targeting a broad trophic diversity of reef-associated species is of particular concern and we suggest such changes in illegal activity in MPAs globally may persist over long timescales unless management is broad and adaptive to individual context. When considering potential solutions, widespread adoption of technology, such as remote surveillance of vessels, can mitigate illegal activities but remains unfeasible for many MPAs globally due to financial and political barriers. Instead, we suggest broader approaches, including a renewed focus on regional approaches to combating illegal fishing, formal bilateral agreements between competent authorities in relevant countries and an increase in community-based work.


Assuntos
COVID-19 , Caça , Humanos , COVID-19/epidemiologia , Pandemias
8.
Front Physiol ; 14: 1142433, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923285

RESUMO

Yolk biogenesis and consumption have been well conserved in oviparous animals throughout evolution. Most egg-laying animals store yolk proteins within the oocytes' yolk granules (Ygs). Following fertilization, the Ygs participate in controlled pathways of yolk breakdown to support the developing embryo's anabolic metabolism. While the unfolding of the yolk degradation program is a crucial process for successful development in many species, the molecular mechanisms responsible for yolk mobilization are still mysterious and have mostly not been explored. Here, we investigate the functional role of the oocyte maternally accumulated mRNAs of a protein phosphatase (PP501) and two aspartic proteases (cathepsin-D 405, CD405 and cathepsin-D 352, CD352) in the yolk degradation and reproduction of the insect vector of Chagas disease Rhodnius prolixus. We found that PP501 and CD352 are highly expressed in the vitellogenic ovary when compared to the other organs of the adult insect. Parental RNAi silencing of PP501 resulted in a drastic reduction in oviposition and increased embryo lethality whereas the silencing of CD352 resulted only in a slight decrease in oviposition and embryo viability. To further investigate the PP501-caused high reproduction impairment, we investigated the Ygs biogenesis during oocyte maturation and the activation of the yolk degradation program at early development. We found that the Ygs biogenesis was deficient during oogenesis, as seen by flow cytometry, and that, although the PP501-silenced unviable eggs were fertilized, the Ygs acidification and acid phosphatase activity were affected, culminating in a full impairment of the yolk proteins degradation at early embryogenesis. Altogether we found that PP501 is required for the oocyte maturation and the activation of the yolk degradation, being, therefore, essential for this vector reproduction.

9.
Conserv Biol ; 36(2): e13858, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34766384

RESUMO

Wildlife trade has rapidly expanded on social media platforms in recent years, offering an easy means for traders to access international markets. Investigating this trade activity poses a complex challenge to researchers seeking to understand online trade and moderators seeking to disrupt illicit and harmful activity. Current survey methods frequently rely on text-based searches and focus on posts in which the advertisement is explicit. However, such approaches risk overlooking a growing volume of relevant content, particularly outside social media groups. We used posts from pages promoting West African birds for trade as a case study to explore the availability of information for making inferences about trade activity on social media, specifically information indicating that trade activity was occurring or that could be used to infer trade routes. We recorded 400 posts from 12 pages that we inferred either promoted or facilitated wildlife trade, of which 19.7% were explicit advertisements and 23.8% contained taxa-related terms. In the remaining 341 posts, profile information was the most common indicator of trade activity, but a variety of indicators (e.g., images of birds in trade and trade enquiries) were identified across imagery, text, and comments. We identified multiple types of geographical information that could help infer trade routes and thus the likely legality of trade, although most were relatively rare and sometimes contradictory. Our findings suggest that triangulating multiple types of information from within, across, and beyond posts is vital for effectively identifying and interpreting wildlife trade content on social media. Therefore, were commend that expert-mediated triangulation should be integrated in and used alongside automated detection systems and moderating practices of social media companies.


Identificación de las Oportunidades para la Triangulación Mediada por Expertos en el Monitoreo del Mercado de Fauna en las Redes Sociales Resumen El mercado de fauna se ha expandido rápidamente en las redes sociales en años recientes, brindando un medio sencillo para que los comerciantes tengan acceso a los mercados internacionales. El estudio de esta actividad comercial representa un reto complejo para los investigadores que buscan entender el comercio en línea y para los moderadores que intentan interrumpir la actividad ilegal y dañina. Los métodos actuales de censos dependen frecuentemente de búsquedas basadas en texto y se enfocan en publicaciones en las que el anuncio es explícito. Sin embargo, dichas estrategias corren el riesgo de ignorar el volumen creciente de contenido relevante, particularmente aquél fuera de los grupos de las redes sociales. Usamos como estudio de caso las publicaciones obtenidas de páginas que promocionaban aves del oeste de África para su comercio y así exploramos la disponibilidad de información para inferir sobre la actividad comercial en las redes sociales, específicamente la información que indicaba que estaba ocurriendo la actividad comercial o que podría usarse para inferir las rutas de comercio de fauna. Registramos 400 publicaciones de doce páginas que inferimos promocionaban o facilitaban el comercio de fauna, de las cuales el 19.7% fueron anuncios explícitos y el 23.8% contenía términos relacionados con los taxones. En las restantes 341 publicaciones, la información del perfil fue el indicador más común de la actividad comercial, pero una variedad de indicadores (p. ej.: imágenes de aves en el mercado o preguntas sobre su venta) también fueron identificados en las imágenes, textos y comentarios. Identificamos diferentes tipos de información geográfica que podría ser útil para inferir rutas de comercio y, por lo tanto, su probable legalidad, aunque en la mayoría de los casos estas rutas fueron poco frecuentes o contradictorias. Nuestros hallazgos sugieren que la triangulación de diferentes tipos de información dentro, entre y más allá de las publicaciones es vital para identificar e interpretar efectivamente contenidos sobre el comercio de fauna en las redes sociales. Por ello recomendamos integrar la triangulación mediada por expertos y usarla en conjunto con los sistemas automatizados de detección y prácticas de moderación con los que cuentan las compañías de redes sociales.


Assuntos
Animais Selvagens , Mídias Sociais , Animais , Aves , Conservação dos Recursos Naturais , Humanos
10.
People Nat (Hoboken) ; 3(5): 990-1013, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34909607

RESUMO

As the COVID-19 pandemic continues to affect societies across the world, the ongoing economic and social disruptions are likely to present fundamental challenges for current and future biodiversity conservation.We review the literature for outcomes of past major societal, political, economic and zoonotic perturbations on biodiversity conservation, and demonstrate the complex implications of perturbation events upon conservation efforts. Building on the review findings, we use six in-depth case studies and the emerging literature to identify positive and negative outcomes of the COVID-19 pandemic, known and anticipated, for biodiversity conservation efforts around the world.A number of similarities exist between the current pandemic and past perturbations, with experiences highlighting that the pandemic-induced declines in conservation revenue and capacity, livelihood and trade disruptions are likely to have long-lasting and negative implications for biodiversity and conservation efforts.Yet, the COVID-19 pandemic also brought about a global pause in human movement that is unique in recent history, and may yet foster long-lasting behavioural and societal changes, presenting opportunities to strengthen and advance conservation efforts in the wake of the pandemic. Enhanced collaborations and partnerships at the local level, cross-sectoral engagement, local investment and leadership will all enhance the resilience of conservation efforts in the face of future perturbations. Other actions aimed at enhancing resilience will require fundamental institutional change and extensive government and public engagement and support if they are to be realised.The pandemic has highlighted the inherent vulnerabilities in the social and economic models upon which many conservation efforts are based. In so doing, it presents an opportunity to reconsider the status quo for conservation, and promotes behaviours and actions that are resilient to future perturbation. A free Plain Language Summary can be found within the Supporting Information of this article.

11.
Front Pharmacol ; 12: 664465, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935787

RESUMO

Purpose: Albendazole is a benzimidazole carbamate drug with anthelmintic and antiprotozoal activity against intestinal and tissue parasites. It has been described that the administration with meals increases albendazole absorption. Our aim was to compare the systemic exposure in healthy volunteers of two albendazole formulations after a single oral dose under fed conditions and to evaluate the effect of breakfast composition on albendazole and albendazole sulfoxide bioavailability. Methods: 12 healthy volunteers were included in a 4-period, 4-sequence, crossover, open, randomized, bioequivalence clinical trial, including two stages to compare two formulations of albendazole. Single oral doses of 400 mg albendazole were administered under fed conditions (a low-fat breakfast in first stage and a high-fat breakfast in the second) separated by 7-day washout periods. Plasma albendazole and albendazole sulfoxide concentrations were measured by HPLC-MS/MS. Findings: Albendazole absorption was clearly influenced by the meal composition. A high-fat breakfast increased albendazole and albendazole sulfoxide area under the concentration-time curve (AUC) and maximum concentration (Cmax) by double, compared to a low-fat breakfast. The bioavailability of the two formulations was very similar, although the sample size was not sufficient to demonstrate bioequivalence because the intraindividual variability of albendazole was approximately 60%. Implications: The higher albendazole and albendazole sulfoxide levels when administered with a high-fat meal could be of importance in clinical practice. Since albendazole labeling recommends its administration with meals, it is necessary to insist on taking it with a fatty meal so that the effectiveness of albendazole is not compromised.

12.
Rev. ADM ; 76(1): 44-48, ene.-feb. 2019. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-996080

RESUMO

Introducción: El término kissing molars se traduce como «dientes besándose¼; superfi cies oclusales de dos molares retenidos están en contacto una con otra en espacio folicular único y raíces en dirección contraria. Literatura científi ca ha reportado 44 casos. Cuartos molares o distomolares, supernumerarios que se forman distalmente a terceros molares; tamaño y forma variable, generalmente retenidos. Caso clínico: Femenino de 32 años con molestias en zona retromolar inferior izquierda, limitación de apertura, trismus, disfagia. En ortopantomografía, se observa cuarto molar retenido junto con tercer molar, superfi cies oclusales de ambos órganos dentarios retenidos en íntimo contacto dentro de un mismo saco folicular, raíces en dirección opuesta. Discusión: Existe controversia acerca de diferencia entre molares retenidos y KM, algunos autores sugieren que la ausencia de contacto entre dos molares retenidos no permite incluirlos en esta condición. Etiología aún incierta, algunos lo consideran como un evento aislado. Existe una teoría en relación con la formación de quiste dentígero; resorción ósea causada por presencia y expansión de éste, resulta en pérdida de hueso en zona mesial de molares retenidos facilitando movilización, inclinación y contacto uno con otro (AU)


Introduction: The term kissing molars is used when the occlusal surfaces of two retained molars are in intimate contact inside the same follicular sack and roots in opposite direction. Literature has reported 44 cases. Fourth molars, also known as distomolars, are a supernumerary tooth that grows distally to third molars; size and shape are variable, generally retained. Case report: Female 32 years old, pain in the left inferior retromolar zone, trismus, dysphagia. Fourth and third retained molars, with occlusal surfaces in contact, inside the same follicular sack, roots in opposite direction are observed in orthopantomography. Discussion: There is controversy about the diff erence between retained molars and KM, some authors suggest that the absence of contact between two retained molars, does not allow to include them in this condition. Etiology still unknown. Dentigerous cyst formation theory is proposed due to the bone resorption in the mesial zone of retained molars in this entity, which facilitates mobilization and contact between molars (AU)


Assuntos
Humanos , Feminino , Adulto , Erupção Ectópica de Dente , Dente Impactado , Dente Supranumerário , Dente Molar/anormalidades , Diagnóstico por Imagem , Radiografia Panorâmica , Recusa do Paciente ao Tratamento
13.
PLoS Negl Trop Dis ; 12(7): e0006661, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30036366

RESUMO

Heme crystallization as hemozoin represents the dominant mechanism of heme disposal in blood feeding triatomine insect vectors of the Chagas disease. The absence of drugs or vaccine for the Chagas disease causative agent, the parasite Trypanosoma cruzi, makes the control of vector population the best available strategy to limit disease spread. Although heme and redox homeostasis regulation is critical for both triatomine insects and T. cruzi, the physiological relevance of hemozoin for these organisms remains unknown. Here, we demonstrate that selective blockage of heme crystallization in vivo by the antimalarial drug quinidine, caused systemic heme overload and redox imbalance in distinct insect tissues, assessed by spectrophotometry and fluorescence microscopy. Quinidine treatment activated compensatory defensive heme-scavenging mechanisms to cope with excessive heme, as revealed by biochemical hemolymph analyses, and fat body gene expression. Importantly, egg production, oviposition, and total T. cruzi parasite counts in R. prolixus were significantly reduced by quinidine treatment. These effects were reverted by oral supplementation with the major insect antioxidant urate. Altogether, these data underscore the importance of heme crystallization as the main redox regulator for triatomine vectors, indicating the dual role of hemozoin as a protective mechanism to allow insect fertility, and T. cruzi life-cycle. Thus, targeting heme crystallization in insect vectors represents an innovative way for Chagas disease control, by reducing simultaneously triatomine reproduction and T. cruzi transmission.


Assuntos
Doença de Chagas/parasitologia , Heme/química , Insetos Vetores/metabolismo , Rhodnius/metabolismo , Trypanosoma cruzi/fisiologia , Animais , Doença de Chagas/transmissão , Cristalização , Feminino , Heme/metabolismo , Humanos , Insetos Vetores/química , Insetos Vetores/parasitologia , Masculino , Oviposição , Oxirredução , Rhodnius/química , Rhodnius/parasitologia
14.
PLoS Negl Trop Dis ; 12(5): e0006498, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29782512

RESUMO

Aedes aegypti is the vector of some of the most important vector-borne diseases like dengue, chikungunya, zika and yellow fever, affecting millions of people worldwide. The cellular processes that follow a blood meal in the mosquito midgut are directly associated with pathogen transmission. We studied the homeostatic response of the midgut against oxidative stress, as well as bacterial and dengue virus (DENV) infections, focusing on the proliferative ability of the intestinal stem cells (ISC). Inhibition of the peritrophic matrix (PM) formation led to an increase in reactive oxygen species (ROS) production by the epithelial cells in response to contact with the resident microbiota, suggesting that maintenance of low levels of ROS in the intestinal lumen is key to keep ISCs division in balance. We show that dengue virus infection induces midgut cell division in both DENV susceptible (Rockefeller) and refractory (Orlando) mosquito strains. However, the susceptible strain delays the activation of the regeneration process compared with the refractory strain. Impairment of the Delta/Notch signaling, by silencing the Notch ligand Delta using RNAi, significantly increased the susceptibility of the refractory strains to DENV infection of the midgut. We propose that this cell replenishment is essential to control viral infection in the mosquito. Our study demonstrates that the intestinal epithelium of the blood fed mosquito is able to respond and defend against different challenges, including virus infection. In addition, we provide unprecedented evidence that the activation of a cellular regenerative program in the midgut is important for the determination of the mosquito vectorial competence.


Assuntos
Aedes/virologia , Proliferação de Células , Vírus da Dengue/fisiologia , Insetos Vetores/virologia , Aedes/citologia , Aedes/metabolismo , Animais , Dengue/transmissão , Dengue/virologia , Feminino , Trato Gastrointestinal/citologia , Trato Gastrointestinal/metabolismo , Humanos , Insetos Vetores/citologia , Insetos Vetores/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
15.
Front Genet ; 9: 19, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29456553

RESUMO

Iron is an essential element for most organisms However, free iron and heme, its complex with protoporphyrin IX, can be extremely cytotoxic, due to the production of reactive oxygen species, eventually leading to oxidative stress. Thus, eukaryotic cells control iron availability by regulating its transport, storage and excretion as well as the biosynthesis and degradation of heme. In the genome of Rhodnius prolixus, the vector of Chagas disease, we identified 36 genes related to iron and heme metabolism We performed a comprehensive analysis of these genes, including identification of homologous genes described in other insect genomes. We observed that blood-meal modulates the expression of ferritin, Iron Responsive protein (IRP), Heme Oxygenase (HO) and the heme exporter Feline Leukemia Virus C Receptor (FLVCR), components of major pathways involved in the regulation of iron and heme metabolism, particularly in the posterior midgut (PM), where an intense release of free heme occurs during the course of digestion. Knockdown of these genes impacted the survival of nymphs and adults, as well as molting, oogenesis and embryogenesis at different rates and time-courses. The silencing of FLVCR caused the highest levels of mortality in nymphs and adults and reduced nymph molting. The oogenesis was mildly affected by the diminished expression of all of the genes whereas embryogenesis was dramatically impaired by the knockdown of ferritin expression. Furthermore, an intense production of ROS in the midgut of blood-fed insects occurs when the expression of ferritin, but not HO, was inhibited. In this manner, the degradation of dietary heme inside the enterocytes may represent an oxidative challenge that is counteracted by ferritins, conferring to this protein a major antioxidant role. Taken together these results demonstrate that the regulation of iron and heme metabolism is of paramount importance for R. prolixus physiology and imbalances in the levels of these key proteins after a blood- meal can be extremely deleterious to the insects in their various stages of development.

16.
PLoS One ; 13(1): e0190594, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29385172

RESUMO

Vultures constitute an important functional group in many ecosystems, providing crucial ecosystem services both in natural and humanized environments. These scavengers are facing massive declines worldwide, but in several African countries virtually nothing is known on populations' status and threats, hampering the development of adequate conservation strategies. In Guinea-Bissau, globally important populations of Hooded Necrosyrtes monachus and African white-backed vultures Gyps africanus were recently reported. Using the country as a study area, we aim to characterize human-vulture interactions in West Africa applying a multidisciplinary approach. We assessed the status and distribution of vulture populations using data from 1711 km of roadside transects, examined predictors of their distribution, and produced a nationwide population estimate for the Hooded Vulture, using an innovative method based on the relationship between the size of human population in settlements and vulture numbers. We conducted 47 stakeholder interviews to assess perceived roles played by vultures, and to investigate potential anthropogenic threats. Hooded vultures were strongly associated with high human population densities, whereas no relation was found between African white-backed and Rüppell's vultures and any of the tested predictors, which included cattle density, precipitation and Normalized Difference Vegetation Index, among others. We estimate a national population of 43347 Hooded vultures, the largest population reported in the species range. Respondents were generally aware of the services provided by vultures, especially waste and carcass removal, including in urban areas. Hunting for witchcraft and traditional medicine was the most frequently recognised threat, while poisoning was ranked as having the highest impact. We hypothesise that poisoning-related mortality may be affecting African white-backed and Rüppell's vultures' distribution and explain their scarcity in apparently highly suitable habitats. Our results suggest a mutualistic rather than a commensalistic relationship between vultures and humans, with important implications for designing and implementing conservation strategies.


Assuntos
Falconiformes/fisiologia , Animais , Conservação dos Recursos Naturais , Ecossistema , Guiné-Bissau , Humanos , Dinâmica Populacional
17.
J Pharm Biomed Anal ; 151: 116-125, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29324280

RESUMO

A simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for simultaneous quantification of aripiprazole and its active metabolite, dehydro-aripiprazole, in human plasma. Stable isotopically labeled aripiprazole, aripiprazole-D8, has been used as the internal standard (IS) for both analytes. Only 200 µl of human plasma was needed for analyte extraction, using effective phospholipids-eliminating three-step microelution-solid-phase extraction (SPE, Oasis PRiME HLB 96-well µElution Plate). An ACE C18-PFP column was applied for chromatographic separation at 25 °C, protected by a 0.2-µm on-line filter. A combination of ammonium formate (5 mM)-acetonitrile (pH 4.0; 65:35, v/v) was used as mobile phase and the chromatogram was run under gradient conditions at a flow rate of 0.6 ml/min. Run time lasted 5 min, followed by a re-equilibration time of 3 min, to give a total run time of 8 min. Five µl of the sample was injected into the chromatographic system. Aripiprazole, dehydro-aripiprazole and IS were detected using the mode multiple reaction monitoring in the positive ionization mode. The method was linear in the concentration range of 0.18-110 ng/ml and 0.35-100 ng/ml for aripiprazole and dehydro-aripiprazole, respectively. Our method has been validated according to the recommendations of regulatory agencies through tests of precision, accuracy, recovery, matrix effect, stability, sensitivity, selectivity and carry-over. Our microelution-SPE method removes more than 99% of main plasma phospholipids compared to protein precipitation and was successfully applied to several bioequivalence studies.


Assuntos
Aripiprazol/sangue , Fosfolipídeos/química , Piperazinas/sangue , Quinolonas/sangue , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Humanos
18.
Conserv Biol ; 32(3): 597-606, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28960440

RESUMO

Cinema offers a substantial opportunity to share messages with a wide audience. However, there is little research or evidence about the potential benefits and risks of cinema for conservation. Given their global reach, cinematic representations could be important in raising awareness of conservation issues and species of concern, as well as encouraging greater audience engagement due to their heightened emotional impact on viewers. Yet there are also risks associated with increased exposure, including heightened visitor pressure to environmentally sensitive areas or changes to consumer demand for endangered species. Conservationists can better understand and engage with the film industry by studying the impact of movies on audience awareness and behavior, identifying measurable impacts on conservation outcomes, and engaging directly with the movie industry, for example, in an advisory capacity. This improved understanding and engagement can harness the industry's potential to enhance the positive impacts of movies featuring species, sites, and issues of conservation concern and to mitigate any negative effects. A robust evidence base for evaluating and planning these engagements, and for informing related policy and management decisions, needs to be built.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Espécies em Perigo de Extinção
19.
Rev. inf. cient ; 97(6): i:1100-f:1110, 2018. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1006461

RESUMO

Introducción: durante los últimos 20 años la incidencia del embarazo ectópico se ha duplicado o triplicado, principalmente en los países desarrollados. Este incremento se comporta de forma diferente en países, regiones o áreas poblacionales. Objetivo: caracterizar el comportamiento del embarazo ectópico en el Hospital General Docente de Guantánamo Dr. Agostinho Neto durante el año 2006. Método: el universo estuvo constituido por 763 pacientes con embarazo ectópico en el período 2002-2006. La muestra fue de 175, todas del año 2006. Las variables estudiadas fueron: grupo de edades, síntomas al ingreso, medios diagnósticos, formas clínicas y operaciones realizadas. Resultados: se obtuvo discreto crecimiento en el número de embarazos ectópicos durante los años de estudio. El grupo de edades de 20-24 obtuvo el 31,4 por ciento en frecuencia y el de 25-29 el 34,9 por ciento. El 85,7 por ciento de las pacientes acudió con los síntomas de dolor bajo vientre y sangramiento vaginal anormal, seguidas por las que presentaron dolor bajo vientre y amenorrea (78,3 por ciento). En 73 pacientes fue diagnosticado por la clínica más culdocentesis en el 41,8 por ciento de los casos y solo en 9 por clínica más laparoscopia. Conclusiones: hubo incremento de los embarazos ectópicos. El año de mayor frecuencia fue 2006. Predominó el grupo de edades de 25 a 29 años y las pacientes primíparas. El síntoma al ingreso predominante fue el dolor bajo vientre y el sangramiento vaginal anormal. El diagnóstico con más frecuencia fue la clínica más culdocentesis. El embarazo ectópico complicado inestable, el sitio de implantación tubárica y la localización ampular con salpingectomía total como operación fueron las más frecuentes(AU)


Introduction: during the last 20 years the incidence of ectopic pregnancy has doubled or tripled, mainly in developed countries. This increase behaves differently in countries, regions or population areas. Objective: to characterize the behavior of ectopic pregnancy in the Guantánamo General Teaching Hospital Dr. Agostinho Neto during the year 2006. Method: the universe consisted of 763 patients with ectopic pregnancy in the period 2002-2006. The sample was 175, all of the year 2006. The variables studied were: age group, symptoms on admission, means of diagnosis, clinical forms and operations performed. Results: discrete growth was obtained in the number of ectopic pregnancies during the years of study. The age group of 20-24 obtained 31.4 percent in frequency and that of 25-29 and 34.9 percent. 85.7 percent of the patients presented with symptoms of abdominal pain and abnormal vaginal bleeding, followed by those with lower abdominal pain and amenorrhea (78.3 percent). In 73 patients it was diagnosed by the clinic plus culdocentesis in 41.8 percent of the cases and only in 9 by clinical plus laparoscopy. Conclusions: there was an increase in ectopic pregnancies. The year of greatest frequency was 2006. The age group of 25 to 29 years and the primiparous patients predominated. The predominant symptom of admission was lower abdominal pain and abnormal vaginal bleeding. The diagnosis with more frequency was the clinic plus culdocentesis. The complicated unstable ectopic pregnancy, the tubal implantation site and the ampullary location with total salpingectomy as the operation were the most frequent(AU)


Introdução: nos últimos 20 anos, a incidência de gravidez ectópica dobrou ou triplicou, principalmente nos países desenvolvidos. Esse aumento se comporta de maneira diferente em países, regiões ou áreas de população. Objetivo: caracterizar o comportamento da gravidez ectópica no Hospital Geral de Ensino de Guantánamo Dr. Agostinho Neto durante o ano de 2006. Método: o universo consistiu em 763 pacientes com gravidez ectópica no período 2002-2006. A amostra foi de 175, durante todo o ano de 2006. As variáveis estudadas foram: faixa etária, sintomas na admissão, meios de diagnóstico, formas clínicas e operações realizadas. Resultados: crescimento discreto foi obtido no número de gestações ectópicas durante os anos de estudo. A faixa etária de 20 a 24 anos obteve 31,4 por cento de frequência e a de 25 a 29 e 34,9 por cento. 85,7 por cento dos pacientes apresentavam sintomas de dor abdominal e sangramento vaginal anormal, seguidos por dor abdominal baixa e amenorreia (78,3 por cento). Em 73 pacientes foi diagnosticada pela clínica mais culdocentese em 41,8 por cento dos casos e somente em 9 pela clínica mais laparoscopia. Conclusões: houve aumento de gravidez ectópica. O ano de maior frequência foi 2006. A faixa etária de 25 a 29 anos e as primíparas predominaram. O sintoma predominante da admissão foi dor no baixo ventre e sangramento vaginal anormal. O diagnóstico com maior frequência foi a clínica e culdocentese. A gestação ectópica complicada e instável, o local de implantação das trompas e a localização ampular com salpingectomia total como operação foram os mais frequentes(AU)


Assuntos
Humanos , Gravidez , Adulto , Gravidez Ectópica/cirurgia , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/epidemiologia
20.
Ther Drug Monit ; 39(3): 252-262, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28490048

RESUMO

BACKGROUND: Imatinib, dasatinib, and nilotinib are tyrosine kinase inhibitors (TKIs) used as first-line treatment of chronic myeloid leukemia. Therapeutic drug monitoring is important to achieve treatment efficacy in the case of imatinib and nilotinib, and to control toxicity in the case of dasatinib. New high-sensitivity methods to monitor those drugs are needed, especially for dasatinib. Thus, a simple method to determine plasma levels of imatinib, dasatinib, and nilotinib for application in clinical practice was developed. METHODS: TKIs were eluted with a Poroshell 120 EC-C18 column (2.1 × 75 mm, 2.7 µm) at 0.5 mL/min and 60°C, under gradient conditions through a mobile phase consisting of 4 mmol/L ammonium formate, pH 3.2 (65%), and acetonitrile (35%). TKIs were detected and quantified by liquid chromatography in tandem with mass spectrometry (LC/MS-MS) with positive electrospray ionization and analytes were extracted using solid phase extraction (Versaplate-SCX). Internal standards were isotope-labeled for each analyte. RESULTS: The method was linear in the range of 2.5-5000 ng/mL for imatinib, 0.75-400 ng/mL for dasatinib, and 2-4000 ng/mL for nilotinib. The validation assays for accuracy and precision, matrix effect, extraction recovery, carryover, and stability of the samples for all the TKIs were appropriate according to regulatory agencies. Furthermore, imatinib plasma samples, stored for 4 years at -80°C were quite stable in approximately half of the samples. CONCLUSIONS: The method enables rapid quantification of TKI concentrations and is being applied to therapeutic drug monitoring to adjust dose and to manage adverse reactions in clinical practice.


Assuntos
Dasatinibe/sangue , Mesilato de Imatinib/sangue , Inibidores de Proteínas Quinases/sangue , Pirimidinas/sangue , Cromatografia Líquida/métodos , Dasatinibe/uso terapêutico , Monitoramento de Medicamentos/métodos , Humanos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
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