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1.
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
2.
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
3.
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
4.
Proc Natl Acad Sci U S A ; 113(35): E5144-52, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27528661

RESUMO

Heme is an essential prosthetic group in proteins that reside in virtually every subcellular compartment performing diverse biological functions. Irrespective of whether heme is synthesized in the mitochondria or imported from the environment, this hydrophobic and potentially toxic metalloporphyrin has to be trafficked across membrane barriers, a concept heretofore poorly understood. Here we show, using subcellular-targeted, genetically encoded hemoprotein peroxidase reporters, that both extracellular and endogenous heme contribute to cellular labile heme and that extracellular heme can be transported and used in toto by hemoproteins in all six subcellular compartments examined. The reporters are robust, show large signal-to-background ratio, and provide sufficient range to detect changes in intracellular labile heme. Restoration of reporter activity by heme is organelle-specific, with the Golgi and endoplasmic reticulum being important sites for both exogenous and endogenous heme trafficking. Expression of peroxidase reporters in Caenorhabditis elegans shows that environmental heme influences labile heme in a tissue-dependent manner; reporter activity in the intestine shows a linear increase compared with muscle or hypodermis, with the lowest heme threshold in neurons. Our results demonstrate that the trafficking pathways for exogenous and endogenous heme are distinct, with intrinsic preference for specific subcellular compartments. We anticipate our results will serve as a heuristic paradigm for more sophisticated studies on heme trafficking in cellular and whole-animal models.


Assuntos
Heme/metabolismo , Hemeproteínas/metabolismo , Espaço Intracelular/metabolismo , Peroxidase/metabolismo , Animais , Animais Geneticamente Modificados , Transporte Biológico , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Membrana Celular/metabolismo , Endocitose , Células HEK293 , Heme/química , Humanos , Microscopia Confocal , Organelas/metabolismo , Peroxidase/química , Peroxidase/genética
5.
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
6.
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
7.
Ther Drug Monit ; 37(3): 381-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25525762

RESUMO

BACKGROUND: Omeprazole (OME) is a proton pump inhibitor with a 58% bioavailability after a single oral dose. It is subject to marked interindividual variations and significant drug-drug interactions. The authors developed a simple and rapid method based on liquid chromatography in tandem with mass spectrometry with solid phase extraction and isotope-labeled internal standard to monitor plasma levels of OME in pharmacokinetics and drug-drug interaction studies. METHODS: OME and its internal standard (OME-D3) were eluted with a Zorbax Extend C-18 rapid resolution column (4.6 × 50 mm, 3.5 µm) at 25°C, under isocratic conditions through a mobile phase consisting of 1 mM ammonium acetate, pH 8.5 (55%), and acetonitrile (45%). The flow rate was 0.8 mL/min, and the chromatogram run time was 1.2 minutes. OME was detected and quantified by liquid chromatography in tandem with mass spectrometry with positive electrospray ionization, which operates in multiple-reaction monitoring mode. RESULTS: The method was linear in the range of 1.5-2000 ng/mL for OME. The validation assays for accuracy and precision, matrix effect, extraction recovery, and stability of the samples for OME did not deviate more than 20% for the lower limit of quantification and no more than 15% for other quality controls. CONCLUSIONS: These findings are consistent with the requirements of regulatory agencies. The method enables rapid quantification of OME concentrations and can be used in pharmacokinetic and drug-drug interaction studies.


Assuntos
Cromatografia Líquida de Alta Pressão , Monitoramento de Medicamentos/métodos , Omeprazol/sangue , Espectrometria de Massas em Tandem , Estabilidade de Medicamentos , Humanos , Extração em Fase Sólida
8.
J Biol Chem ; 288(41): 29323-32, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23986441

RESUMO

The heme molecule is the prosthetic group of many hemeproteins involved in essential physiological processes, such as electron transfer, transport of gases, signal transduction, and gene expression modulation. However, heme is a pro-oxidant molecule capable of propagating reactions leading to the generation of reactive oxygen species. The blood-feeding insect Rhodnius prolixus releases enormous amounts of heme during host blood digestion in the midgut lumen when it is exposed to a physiological oxidative challenge. Additionally, this organism produces a hemolymphatic heme-binding protein (RHBP) that transports heme to pericardial cells for detoxification and to growing oocytes for yolk granules and as a source of heme for embryo development. Here, we show that silencing of RHBP expression in female fat bodies reduced total RHBP circulating in the hemolymph, promoting oxidative damage to hemolymphatic proteins. Moreover, RHBP knockdown did not cause reduction in oviposition but led to the production of heme-depleted eggs (white eggs). A lack of RHBP did not alter oocyte fecundation. However, produced white eggs were nonviable. Embryo development cellularization and vitellin yolk protein degradation, processes that normally occur in early stages of embryogenesis, were compromised in white eggs. Total cytochrome c content, cytochrome c oxidase activity, citrate synthase activity, and oxygen consumption, parameters that indicate mitochondrial function, were significantly reduced in white eggs compared with normal dark red eggs. Our results showed that reduction of heme transport from females to growing oocytes by RHBP leads to embryonic mitochondrial dysfunction and impaired embryogenesis.


Assuntos
Proteínas de Transporte/genética , Hemeproteínas/genética , Mitocôndrias/metabolismo , Interferência de RNA , Rhodnius/genética , Animais , Transporte Biológico , Western Blotting , Proteínas de Transporte/metabolismo , Corpo Adiposo/embriologia , Corpo Adiposo/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Heme/metabolismo , Proteínas Ligantes de Grupo Heme , Hemeproteínas/metabolismo , Hemolinfa/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Oócitos/ultraestrutura , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rhodnius/embriologia , Rhodnius/metabolismo , Zigoto/crescimento & desenvolvimento , Zigoto/metabolismo
9.
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
10.
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
11.
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
12.
Conserv Biol ; 27(6): 1355-65, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24001112

RESUMO

Assessing anthropogenic effects on biological diversity, identifying drivers of human behavior, and motivating behavioral change are at the core of effective conservation. Yet knowledge of people's behaviors is often limited because the true extent of natural resource exploitation is difficult to ascertain, particularly if it is illegal. To obtain estimates of rule-breaking behavior, a technique has been developed with which to ask sensitive questions. We used this technique, unmatched-count technique (UCT), to provide estimates of bushmeat poaching, to determine motivation and seasonal and spatial distribution of poaching, and to characterize poaching households in the Serengeti. We also assessed the potential for survey biases on the basis of respondent perceptions of understanding, anonymity, and discomfort. Eighteen percent of households admitted to being involved in hunting. Illegal bushmeat hunting was more likely in households with seasonal or full-time employment, lower household size, and longer household residence in the village. The majority of respondents found the UCT questions easy to understand and were comfortable answering them. Our results suggest poaching remains widespread in the Serengeti and current alternative sources of income may not be sufficiently attractive to compete with the opportunities provided by hunting. We demonstrate that the UCT is well suited to investigating noncompliance in conservation because it reduces evasive responses, resulting in more accurate estimates, and is technically simple to apply. We suggest that the UCT could be more widely used, with the trade-off being the increased complexity of data analyses and requirement for large sample sizes. Una Aproximación Novedosa para Evaluar la Prevalencia y Factores de la Cacería Ilegal en el Serengueti.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Atividades Humanas , Adolescente , Adulto , Idoso , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Estações do Ano , Fatores Socioeconômicos , Tanzânia
13.
Biomed Chromatogr ; 27(4): 502-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23034891

RESUMO

We have developed a method of liquid chromatography in tandem with mass spectrometry to monitor therapeutic levels of imatinib in plasma, a selective inhibitor of protein tyrosine kinase. After solid-phase extraction of plasma samples, imatinib and its internal standard, imatinib-D8, were eluted with Zorbax SB-C18 at 60 °C, under isocratic conditions through a mobile phase consisting of 4 mm ammonium formate, pH: 3.2 (solution A) and acetonitrile solution B. The flow rate was 0.8 mL/min with 55% solution A + 45% solution B. Imatinib was detected and quantified by mass spectrometry with electrospray ionization operating in selected-reaction monitoring mode. The calibration curve was linear in the range 10-5000 ng/mL, the lower limit of quantitation being 10 ng/mL. The method was validated according to the recommendations of the Food and Drug Administration, including tests of matrix effect (bias < 10%) and recovery efficiency (>80 and <120%). The method is precise (coefficient of variance intra-day <2% and inter-day <7%), accurate (95-108%), sensitive and specific. It is a simple method with very fast recording time (1.2 min) that is applicable to clinical practice. This will permit improvement of the pharmacological treatment of patients.


Assuntos
Antineoplásicos/sangue , Benzamidas/sangue , Cromatografia Líquida de Alta Pressão/métodos , Piperazinas/sangue , Inibidores de Proteínas Quinases/sangue , Pirimidinas/sangue , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Monitoramento de Medicamentos/métodos , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Limite de Detecção
14.
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
15.
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.

16.
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.

17.
J Pharmacol Exp Ther ; 342(2): 263-72, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22537772

RESUMO

The present study was planned to investigate the action of pregabalin on voltage-dependent Ca(2+) channels (VDCCs) and novel targets (fusion pore formed between the secretory vesicle and the plasma membrane, exocytotic machinery, and mitochondria) that would further explain its inhibitory action on neurotransmitter release. Electrophysiological recordings in the perforated-patch configuration of the patch-clamp technique revealed that pregabalin inhibits by 33.4 ± 2.4 and 39 ± 4%, respectively, the Ca(2+) current charge density and exocytosis evoked by depolarizing pulses in mouse chromaffin cells. Approximately half of the inhibitory action of pregabalin was rescued by l-isoleucine, showing the involvement of α2δ-dependent and -independent mechanisms. Ca(2+) channel blockers were used to inhibit Cav1, Cav2.1, and Cav2.2 channels in mouse chromaffin cells, which were unselectively blocked by the drug. Similar values of Ca(2+) current charge blockade were obtained when pregabalin was tested in human or bovine chromaffin cells, which express very different percentages of VDCC types with respect to mouse chromaffin cells. These results demonstrate that the inhibitory action of pregabalin on VDCCs and exocytosis does not depend on α1 Ca(2+) channel subunit types. Carbon fiber amperometric recordings of digitonin-permeabilized cells showed that neither the fusion pore nor the exocytotic machinery were targeted by pregabalin. Mitochondrial Ca(2+) measurements performed with mitochondrial ratiometric pericam demonstrated that Ca(2+) uptake or release from mitochondria were not affected by the drug. The selectivity of action of pregabalin might explain its safety, good tolerability, and reduced adverse effects. In addition, the inhibition of the exocytotic process in chromaffin cells might have relevant clinical consequences.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Canais de Cálcio/metabolismo , Células Cromafins/efeitos dos fármacos , Células Cromafins/metabolismo , Exocitose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Ácido gama-Aminobutírico/análogos & derivados , Glândulas Suprarrenais/metabolismo , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Bovinos , Humanos , Isoleucina/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Mitocôndrias/metabolismo , Neurotransmissores/metabolismo , Pregabalina , Ácido gama-Aminobutírico/farmacologia
18.
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.

19.
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.

20.
Biochem Biophys Res Commun ; 391(1): 722-6, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19944073

RESUMO

The novel Ca(2+) channel CALHM1 (Calcium Homeostasis Modulator 1) generates cytosolic Ca(2+) transients ([Ca(2+)](c)) that regulate the production of amyloid beta (Abeta). Its mutated channel P86L-CALHM1 has been associated to Alzheimer's disease (AD). Using cytosolic- and mitochondrial-targeted aequorins, we have investigated here whether mitochondria sense with similar or different kinetics the Ca(2+) entering into Hela cells and the Ca(2+) released from the endoplasmic reticulum (ER), in control and in cells transfected with CALHM1 and P86L-CALHM1. We have shown that mitochondria sense Ca(2+) entry in the three cell types; however, the [Ca(2+)](c) and mitochondrial Ca(2+) transients [Ca(2+)](m) had substantially slower kinetics in cells expressing P86L-CALHM1. Mitochondria also sensed the ER Ca(2+) released by histamine, but in CALHM1 and P86L-CALHM1 cells the kinetics was faster than that of control cells. Data are compatible with the idea that mutated CALHM1 may cause mitochondrial Ca(2+) overload, suggesting how these cells may become more vulnerable to apoptotic stimuli.


Assuntos
Apoptose , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Glicoproteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Substituição de Aminoácidos , Canais de Cálcio/genética , Retículo Endoplasmático/metabolismo , Células HeLa , Humanos , Cinética , Leucina/genética , Leucina/metabolismo , Glicoproteínas de Membrana/genética , Mutação , Prolina/genética , Prolina/metabolismo
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