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1.
Arch Insect Biochem Physiol ; 114(1): e22029, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37278151

RESUMO

Inorganic polyphosphate (polyP) is a biopolymer composed of phosphoanhydride-linked orthophosphate molecules. PolyP is engaged in a variety of cellular functions, including mitochondrial metabolism. Here, we examined the effects of polyP on electron transport chain enzymes and F1 Fo ATP synthase in tick embryos during embryonic development. The study found that polyPs containing medium and long chains (polyP15 and polyP65 ) enhanced the activity of complex I, complex II, complex III, and F1 Fo ATP synthase, while short polyP chains (polyP3 ) had no effect. The study also examined the activity of exopolyphosphatases (PPX) in various energy-demand situations. PPX activity was stimulated when ADP concentrations are high, characterizing a low-energy context. When complexes I-III and F1 Fo ATP synthase inhibitors were added in energized mitochondria, PPX activity decreased, whereas the mitochondrial uncoupler FCCP had no impact on PPX activity. Additionally, the study investigated the effect of polyP on mitochondrial swelling, finding that polyP causes mitochondrial swelling by increasing calcium effects on the mitochondrial permeability transition pore. The findings presented here to increase our understanding of the function of polyP in mitochondrial metabolism and its relationship to mitochondrial permeability transition pore opening in an arthropod model.


Assuntos
Poro de Transição de Permeabilidade Mitocondrial , Carrapatos , Animais , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/farmacologia , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/farmacologia , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Polifosfatos/farmacologia , Polifosfatos/metabolismo , Cálcio/metabolismo
2.
Metabolomics ; 17(9): 79, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34463832

RESUMO

INTRODUCTION: Metabolomic approaches can assess the actual state of an organism's energy metabolism during a specific morphological event, providing a more accurate insight into the correlations between physiology and metabolic regulation. METHODS: The study of the metabolomic profile aim to identify the largest possible number of biomolecules in a certain organism or specific structures. For this purpose, mass spectrometry (MS) and chromatography have been used in the present study. OBJECTIVES: In this context, the aim of the present work is to evaluate the glucose metabolomic profile during embryogenesis in Rhipicephalus microplus tick, investigating the dynamics of nutrient utilization during tick embryo formation, as well as the control of glucose metabolism. RESULTS: We show that glycogen reserves are preferentially mobilized to sustain the energy-intensive process of embryogenesis. Subsequently, the increase in concentration of specific amino acids indicates that protein degradation would provide carbons to fuel gluconeogenesis, supplying the embryo with sufficient glucose and glycogen during development. CONCLUSION: Altogether, these results demonstrated the presence of a very refined catabolic and anabolic control during embryogenesis in R. microplus tick, suggesting the pronounced gluconeogenesis as a strategy to secure embryo development. Moreover, this research contributes to the understanding of the mechanisms that control glucose metabolism during tick embryogenesis and may aid the identification of putative targets for novel chemical or immunological control methods, which are essential to improve the prevention of tick infestations.


Assuntos
Rhipicephalus , Infestações por Carrapato , Animais , Desenvolvimento Embrionário , Glucose , Glicogênio
3.
Environ Monit Assess ; 193(12): 789, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34757510

RESUMO

Rainfall is generally partitioned into throughfall, stemflow, and interception in ecosystems. Stemflow variability can affect the hydrology, ecology, and soil chemistry patterns. However, the influence of canopy structure and rainfall characteristics on stemflow production in sugarcane plantations which are important for renewable energy production remain poorly understood. By using funnels attached to the sugarcane stems, the present study determined the stemflow amount during the period of sugarcane growth and its relationship with plant development. Approximately, 14% of gross rainfall reached the soil as stemflow, and the funneling ratios was 60. In general, it was observed a positive relationship between stemflow rates with both leaf area index and plant height. This was attributed to an increasing number of acute branching angles of the sugarcane leaves as well as high stem tillering and density. However, at the end of growth cycle, stemflow rate was lower than in previous periods which can be attributed to changes in sugarcane canopy such as stems inclination and lodging, reducing the effectiveness of water conveyance along the stem. Our study showed the need to include stemflow to better understand the hydrology of sugarcane plantations.


Assuntos
Chuva , Saccharum , Ecossistema , Monitoramento Ambiental , Solo , Árvores
4.
Waste Manag Res ; 39(11): 1331-1340, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34525881

RESUMO

The processes related to solid waste management (SWM) are being revised as new technologies emerge and are applied in the area to achieve greater environmental, social and economic sustainability for society. To achieve our goal, two robust review protocols (Population, Intervention, Comparison, Outcome, and Context (PICOC) and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA)) were used to systematically analyze 62 documents extracted from the Web of Science database to identify the main techniques and tools for Knowledge Discovery in Databases (KDD) and Data Mining (DM) as applied to SWM and explore the technological potential to optimize the stages of collecting and transporting waste. Moreover, it was possible to analyze the main challenges and opportunities of KDD and DM for SWM. The results show that the most used tools for SWM are MATLAB (29.7%) and GIS (13.5%), whereas the most used techniques are Artificial Neural Networks (35.8%), Linear Regression (16.0%) and Support Vector Machine (12.3%). In addition, 15.3% of the studies were conducted with data from China, 11.1% from India and 9.7% of the studies analyzed and compared data from several other countries. Furthermore, the research showed that the main challenges in the field of study are related to the collection and treatment of data, whereas the opportunities appear to be linked mainly to the impact on the pillars of sustainable development. Thus, this study portrays important issues associated with the use of KDD and DM for optimal SWM and has the potential to assist and direct researchers and field professionals in future studies.


Assuntos
Resíduos Sólidos , Gerenciamento de Resíduos , Mineração de Dados , Bases de Dados Factuais , Descoberta do Conhecimento , Resíduos Sólidos/análise
5.
Arch Insect Biochem Physiol ; 102(4): e21606, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31498484

RESUMO

Polyphosphates (polyPs) have been found in all cell types examined to date and play diverse roles, depending on the cell type. In eukaryotic organisms, polyPs have been mainly investigated in mammalian cells, with few studies on insects. In this study, we investigated mitochondrial polyphosphate metabolism in the red flour beetle, Tribolium castaneum. Substrate specificity for different chain lengths demonstrated the presence of two exopolyphosphatase isoforms in mitochondria. T. castaneum mitochondrial polyP levels decreased after injection with soluble pyrophosphatase (Tc-sPPase) dsRNA, while the membrane exopolyphosphate activity increased. Mitochondrial respiration modulated exopolyphosphatase activity only in wild-type beetles. Tripolyphosphate was able to increase the F-ATPase activity in wild-type and Tc-sPPase RNAi beetles. We suggest that inorganic pyrophosphatase modulates polyphosphate metabolism in mitochondria and affects the link between mitochondrial activity and polyphosphate metabolism in T. castaneum.


Assuntos
Pirofosfatase Inorgânica/metabolismo , Mitocôndrias/metabolismo , Polifosfatos/metabolismo , Tribolium/enzimologia , Adenosina Trifosfatases , Animais , Feminino , Pirofosfatase Inorgânica/química , Proteínas de Insetos/metabolismo , Masculino , Interferência de RNA , Tribolium/metabolismo
6.
Environ Monit Assess ; 192(1): 26, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823024

RESUMO

The spread of the exotic species Hovenia dulcis known as Japanese raisin tree, coming from Asia, detected in a protected area of 465.0 ha surrounding the city of Santa Cruz do Sul, RS, Brazil, named "Green Belt." In this context, this research aimed at developing an aerial monitoring system able to identify and quantify the extension in the Green Belt area that this species invaded, as well as describing the impacts caused on the local forest community. We collected data from an ultralight Flyer GT aircraft equipped with a vertical camera. The images were taking in June and July 2015, when H. dulcis trees have shed their leaves, displaying a gray color, and September and October 2015, when the leaves are young and with a light green color. Based on the methodology proposed trough aerial monitoring by photogrammetry, the results indicated that the total invaded area by H. dulcis in the Green Belt of Santa Cruz do Sul County, RS, was 131.8 ha, corresponding to 20.9% of the total area. To validate this method, a quantitative comparison between the result from a terrestrial fieldwork carried out and the proposed method showed no significant differences in the estimated area occupied by H. dulcis. We concluded that these results validate the proposed aerial assessment method.


Assuntos
Monitoramento Ambiental/métodos , Espécies Introduzidas , Fotogrametria , Dispersão Vegetal , Rhamnaceae/fisiologia , Brasil
7.
J Med Entomol ; 53(1): 206-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26487245

RESUMO

Leishmania (L.) amazonensis (Lainson & Shaw, 1972) and Leishmania (Viannia) braziliensis (Vianna, 1911) are the principal causative agents of American tegumentary leishmaniasis (ATL) in Brazil. L. amazonensis also causes diffuse cutaneous leishmaniasis (DCL) vectored principally by Lutzomyia flaviscutellata and secondarily by Lutzomyia whitmani (Antunes & Coutinho, 1939). The latter is the most common phlebotomine in the state of Maranhão, and it is the focal species for potential ATL transmission. For this reason, we tested the ability of L. whitmani to become infected with Lutzomyia parasites. Phlebotomines were derived from a colony maintained in the laboratorial conditions. The first generation, uninfected females were offered a bloodmeal with mice infected with the strains of both parasites. We found that L. whitmani can become infected with both parasite species, with infection rates of 65.2% (L. braziliensis) and 47.4% (L. amazonensis). We conclude that in Maranhão, L. whitmani is likely an important vector in the transmission of ATL and may function as a vector of DCL. This possibility should be further investigated.


Assuntos
Insetos Vetores/microbiologia , Leishmania braziliensis/fisiologia , Psychodidae/microbiologia , Animais , Feminino , Leishmaniose Cutânea/transmissão
8.
Mar Drugs ; 14(2)2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26821032

RESUMO

Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (-)-elatol and (+)-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (-)-elatol showed moderate larvicidal activity, whereas (+)-obtusol presented higher toxic activity than (-)-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+)-obtusol revealed damage to the intestinal epithelium. Moreover, (+)-obtusol-treated larvae incubated with 2 µM CM-H2DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+)-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound.


Assuntos
Inseticidas/farmacologia , Laurencia/química , Sesquiterpenos/farmacologia , Aedes , Animais , Brasil , Dengue/transmissão , Controle de Insetos/métodos , Insetos Vetores , Inseticidas/administração & dosagem , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Dose Letal Mediana , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/administração & dosagem , Sesquiterpenos/isolamento & purificação
9.
Int J Mol Sci ; 16(4): 6631-44, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25811926

RESUMO

Polyphosphates have been found in all cell types examined to date and play diverse roles depending on the cell type. In eukaryotic organisms, polyphosphates have been mainly investigated in mammalian cells with few studies on insects. Some studies have demonstrated that a pyrophosphatase regulates polyphosphate metabolism, and most of them were performed on trypanosomatids. Here, we investigated the effects of sPPase gene knocked down in oogenesis and polyphosphate metabolism in the red flour beetle (Tribolium castaneum). A single sPPase gene was identified in insect genome and is maternally provided at the mRNA level and not restricted to any embryonic or extraembryonic region during embryogenesis. After injection of Tc-sPPase dsRNA, female survival was reduced to 15% of the control (dsNeo RNA), and egg laying was completely impaired. The morphological analysis by nuclear DAPI staining of the ovarioles in Tc-sPPase dsRNA-injected females showed that the ovariole number is diminished, degenerated oocytes can be observed, and germarium is reduced. The polyphosphate level was increased in cytoplasmic and nuclear fractions in Tc-sPPase RNAi; Concomitantly, the exopolyphosphatase activity decreased in both fractions. Altogether, these data suggest a role for sPPase in the regulation on polyphosphate metabolism in insects and provide evidence that Tc-sPPase is essential to oogenesis.


Assuntos
Proteínas de Insetos , Oogênese , Polifosfatos/metabolismo , Pirofosfatases/genética , Tribolium/enzimologia , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Proteínas de Insetos/metabolismo , Filogenia , Pirofosfatases/metabolismo
10.
Int J Mol Sci ; 16(1): 1821-39, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25594873

RESUMO

In this work we evaluated several genes involved in gluconeogenesis, glycolysis and glycogen metabolism, the major pathways for carbohydrate catabolism and anabolism, in the BME26 Rhipicephalus microplus embryonic cell line. Genetic and catalytic control of the genes and enzymes associated with these pathways are modulated by alterations in energy resource availability (primarily glucose). BME26 cells in media were investigated using three different glucose concentrations, and changes in the transcription levels of target genes in response to carbohydrate utilization were assessed. The results indicate that several genes, such as glycogen synthase (GS), glycogen synthase kinase 3 (GSK3), phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6 phosphatase (GP) displayed mutual regulation in response to glucose treatment. Surprisingly, the transcription of gluconeogenic enzymes was found to increase alongside that of glycolytic enzymes, especially pyruvate kinase, with high glucose treatment. In addition, RNAi data from this study revealed that the transcription of gluconeogenic genes in BME26 cells is controlled by GSK-3. Collectively, these results improve our understanding of how glucose metabolism is regulated at the genetic level in tick cells.


Assuntos
Gluconeogênese , Glucose/metabolismo , Rhipicephalus/metabolismo , Animais , Linhagem Celular , Regulação da Expressão Gênica , Glucose/genética , Rhipicephalus/citologia , Rhipicephalus/embriologia , Rhipicephalus/genética
11.
J Med Entomol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808616

RESUMO

Numerous sand fly species have been reported in Lençóis Maranhenses National Park (LMNP) in Northeast Brazil, including important Leishmania vectors, making the park an endemic area for tegumentary and visceral leishmaniasis. We evaluated sand fly abundance monthly over 7 years, correlating it with environmental variables and monthly tourist numbers in LMNP. Sand fly species were observed throughout the year, with Lutzomyia longipalpis Lutz & Neiva and Nyssomyia whitmani Antunes and Coutinho (Diptera: Psychodidae) being the most abundant species, especially from April to June. In addition to seasonal abundance patterns, Lu. longipalpis showed increasing abundance throughout 2013 until April 2014, whereas Ny. whitmani exhibited a consistent increase throughout the study period. Redundancy analysis indicated that monthly sand fly abundances increased with humidity but decreased with mean temperature and wind speed. Ecotourists mainly visit the park from May to September when interdune lagoons are full, coinciding with high-frequency vector activity during the rainy months (May-June). Tourists also visit in January and February during school holidays, when the rains begin and sand fly abundance increases, and in July, when sand fly abundance decreases. To date, no instances of infected tourists have been recorded, likely because visits to LMNP occur during the day when sand flies are inactive. However, there is a potential risk of vector exposure if tourists engage in nighttime cultural visits to villages around the park, where leishmaniasis cases occur annually.

12.
Genesis ; 51(12): 803-18, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24166799

RESUMO

Chelicerates, which include spiders, ticks, mites, scorpions, and horseshoe crabs, are members of the phylum Arthropoda. In recent years, several molecular experimental studies of chelicerates have examined the embryology of spiders; however, the embryology of other groups, such as ticks (Acari: Parasitiformes), has been largely neglected. Ticks and mites are believed to constitute a monophyletic group, the Acari. Due to their blood-sucking activities, ticks are also known to be vectors of several diseases. In this study, we analyzed the embryonic development of the cattle tick, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). First, we developed an embryonic staging system consisting of 14 embryonic stages. Second, histological analysis and antibody staining unexpectedly revealed the presence of a population of tick cells with similar characteristics to the spider cumulus. Cumulus cell populations also exist in other chelicerates; these cells are responsible for the breaking of radial symmetry through bone morphogenetic protein signaling. Third, it was determined that the posterior (opisthosomal) embryonic region of R. microplus is segmented. Finally, we identified the presence of a transient ventral midline furrow and the formation and regression of a fourth leg pair; these features may be regarded as hallmarks of late tick embryogenesis. Importantly, most of the aforementioned features are absent from mite embryos, suggesting that mites and ticks do not constitute a monophyletic group or that mites have lost these features. Taken together, our findings provide fundamental common ground for improving knowledge regarding tick embryonic development, thereby facilitating the establishment of a new chelicerate model system.


Assuntos
Rhipicephalus/embriologia , Animais , Evolução Biológica , Bovinos , Células do Cúmulo/citologia , Embrião não Mamífero/anatomia & histologia , Embrião não Mamífero/citologia , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário , Feminino , Modelos Animais , Filogenia , Rhipicephalus/citologia
13.
Int J Mol Sci ; 13(10): 13118-33, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23202941

RESUMO

In the present work, we produced two monoclonal antibodies (BrBm37 and BrBm38) and tested their action against the triosephosphate isomerase of Rhipicephalus (Boophilus) microplus (RmTIM). These antibodies recognize epitopes on both the native and recombinant forms of the protein. rRmTIM inhibition  by BrBm37 was up to 85% whereas that of BrBrm38 was 98%, depending on the antibody-enzyme ratio. RmTIM activity was lower in ovarian, gut, and fat body tissue extracts treated with BrBm37 or BrBm38 mAbs. The proliferation of the embryonic tick cell line (BME26) was inhibited by BrBm37 and BrBm38 mAbs. In summary, the results reveal that it is possible to interfere with the RmTIM function using antibodies, even in intact cells.


Assuntos
Anticorpos Monoclonais/imunologia , Rhipicephalus/enzimologia , Triose-Fosfato Isomerase/metabolismo , Tecido Adiposo/enzimologia , Animais , Linhagem Celular , Proliferação de Células , Feminino , Intestinos/enzimologia , Ovário/enzimologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Triose-Fosfato Isomerase/genética , Triose-Fosfato Isomerase/imunologia
14.
J Med Entomol ; 59(1): 240-247, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34632513

RESUMO

Biting midges are widespread in Brazilian natural ecosystems. However, deforestation and other activities that impact the environment are reducing natural habitats where biting midges proliferate. The objective of this study was to verify whether there is variation in the composition, richness, abundance, and seasonality of biting midges between wild and rural environments, in a forest area with intense deforestation. Biting midges were captured using 6 traps installed at an average height of 1.5 m in the peridomicile, intradomicile, and deciduous seasonal forests, once a month from May 2012 to April 2013. In total, 2,182 specimens of 13 species of the genus Culicoides were captured. Species richness was similar in the intradomicile (13 species), forest (12), and peridomicile (11), but species diversity was greater in the peridomicile (H' = 0.803) compared with the intradomicile (H' = 0.717) and forest (H' = 0.687). The order of species dominance varied between the forest (Culicoides paucienfuscatus Barbosa > Culicoides leopodoi Ortiz > Culicoides foxi Ortiz > Culicoides ignacioi Forattini) and peridomicile + intradomicile habitats (C. paucienfuscatus > C. foxi > C. filariferus Hoffman > C. ignacioi). The activity of these dipterans was strongly influenced by meteorological variables, as biting midges are predominant in the rainy season (80.7% of specimens), when higher rainfall, relative humidity, and lower temperatures prevail. The abundance of biting midges was higher in the peridomicile + intradomicile (83.7% of specimens) compared with the degraded forest (16.3%), a result that reflects the loss of forest habitat due to intense and progressive deforestation.


Assuntos
Ceratopogonidae/classificação , Classificação , Animais , Brasil , Ecossistema , Florestas , Insetos Vetores/classificação , População Rural , Estações do Ano
15.
Int J Mol Sci ; 12(6): 3525-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21747692

RESUMO

The physiological roles of polyphosphates (polyP) recently found in arthropod mitochondria remain obscure. Here, the relationship between the mitochondrial membrane exopolyphosphatase (PPX) and the energy metabolism of hard tick Rhipicephalus microplus embryos are investigated. Mitochondrial respiration was activated by adenosine diphosphate using polyP as the only source of inorganic phosphate (P(i)) and this activation was much greater using polyP(3) than polyP(15). After mitochondrial subfractionation, most of the PPX activity was recovered in the membrane fraction and its kinetic analysis revealed that the affinity for polyP(3) was 10 times stronger than that for polyP(15). Membrane PPX activity was also increased in the presence of the respiratory substrate pyruvic acid and after addition of the protonophore carbonyl cyanide-p-trifluoromethoxyphenylhydrazone. Furthermore, these stimulatory effects disappeared upon addition of the cytochrome oxidase inhibitor potassium cyanide and the activity was completely inhibited by 20 µg/mL heparin. The activity was either increased or decreased by 50% upon addition of dithiothreitol or hydrogen peroxide, respectively, suggesting redox regulation. These results indicate a PPX activity that is regulated during mitochondrial respiration and that plays a role in adenosine-5'-triphosphate synthesis in hard tick embryos.


Assuntos
Hidrolases Anidrido Ácido/metabolismo , Embrião não Mamífero/metabolismo , Mitocôndrias/enzimologia , Rhipicephalus/crescimento & desenvolvimento , Hidrolases Anidrido Ácido/química , Animais , Transporte de Elétrons/efeitos dos fármacos , Metabolismo Energético , Heparina/química , Heparina/metabolismo , Cinética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Membranas Mitocondriais/enzimologia , Membranas Mitocondriais/metabolismo , Oxirredução , Polifosfatos/química , Polifosfatos/farmacologia , Cianeto de Potássio/química , Cianeto de Potássio/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-34015437

RESUMO

The mosquito Aedes aegypti undertakes a shift in carbohydrate metabolism during embryogenesis, including an increase in the activity of phosphoenolpyruvate carboxykinase (PEPCK), a key gluconeogenic enzyme, at critical steps of embryo development. All eukaryotes studied to date present two PEPCK isoforms, namely PEPCK-M (mitochondrial) and PEPCK-C (cytosolic). In A. aegypti, however, these proteins are so far uncharacterized. In the present work we describe two A. aegypti PEPCK isoforms by sequence alignment, protein modeling, and transcription analysis in different tissues, as well as PEPCK enzymatic activity assays in mitochondrial and cytoplasmic compartments during oogenesis and embryogenesis. First, we characterized the protein sequences compared to other organisms, and identified conserved sites and key amino acids. We also performed structure modeling for AePEPCK(M) and AePEPCK(C), identifying highly conserved structural sites, as well as a signal peptide in AePEPCK(M) localized in a very hydrophobic region. Moreover, after blood meal and during mosquito oogenesis and embryogenesis, both PEPCKs isoforms showed different transcriptional profiles, suggesting that mRNA for the cytosolic form is transmitted maternally, whereas the mitochondrial form is synthesized by the zygote. Collectively, these results improve our understanding of mosquito physiology and may yield putative targets for developing new methods for A. aegypti control.


Assuntos
Citosol/metabolismo , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Gluconeogênese , Glucose/metabolismo , Oogênese , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Aedes , Sequência de Aminoácidos , Animais , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Filogenia , Isoformas de Proteínas , Homologia de Sequência
17.
Artigo em Inglês | MEDLINE | ID: mdl-33930525

RESUMO

DNA topoisomerase II enzymes maintain DNA stability during vital processes, such as genome replication, transcription and chromosomal segregation during mitosis and meiosis. In the present work, we analyzed functional aspects of the DNA topoisomerase II (AeTopII) enzyme of the mosquito Aedes aegypti. Here, we show that AeTopII mRNA is expressed at all stages of mosquito development. By in situ hybridization, we found that the AeTopII mRNA is concentrated along the ovarian follicular cells as well as in the region of the follicles. The observed expression profiles likely reflect increased topoisomerase II cellular requirements due to the intense ovarian growth and egg production following blood feeding in Ae. aegypti females. The drug etoposide, a classic inhibitor of topoisomerase II, was used for in vivo testing with 2nd stage larvae, in order to investigate the functional importance of this enzyme in Ae. aegypti survival and development. Inhibition of topoisomerase II activity with etoposide concentrations ranging from 10 to 200 µM did not leads to the immediate death of larvae. However, after 10 days of observation, etoposide treatments resulted in 30-40% decrease in survival, in a dose dependent manner, with persisting larvae and pupae presenting incomplete development, as well as morphological abnormalities. Also, approximately 50% of the treated larvae did not reach the pupal stage. Thus, we conclude that AeTopII is a vital enzyme in the development of Ae. aegypti and its sensitivity to inhibitors should be explored for potential chemical agents to be used in vector control.


Assuntos
Aedes , DNA Topoisomerases Tipo II/metabolismo , Etoposídeo/toxicidade , Larva/efeitos dos fármacos , Mosquitos Vetores/efeitos dos fármacos , Inibidores da Topoisomerase II/toxicidade , Aedes/enzimologia , Aedes/crescimento & desenvolvimento , Animais
18.
J Bodyw Mov Ther ; 26: 72-76, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33992300

RESUMO

The Schwartz-Jampel Syndrome (SJS) is a rare genetic disorder characterized by myotonia and bone dysplasia, which may change the posture. The subject of this case report was a seven-year-old boy diagnosed with SJS and presenting generalized muscle and joints contractures. The purpose of the present case report was to identify postural asymmetries in a patient with SJS through photogrammetry. Postural analysis was conducted using photogrammetry with the Postural Assessment Software (SAPO®). Photogrammetry is a postural assessment system performed through photographic images. These images are acquired by camera and transported to the computer. SAPO® software performs the assessment of this photograph throughout 3D analysis and compares with a predefined protocol. The results of the present case report document several recurrent postural imbalances seen in SJS including myotonia, facial dysmorphism, and skeletal deformities. Thus, even with little evidence in the literature, physical therapy treatment is indicated to increase the functionality of the individual.


Assuntos
Osteocondrodisplasias , Criança , Computadores , Humanos , Masculino , Músculos , Fotogrametria , Postura
19.
BMC Dev Biol ; 10: 25, 2010 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-20184739

RESUMO

BACKGROUND: The mosquito A. aegypti is vector of dengue and other viruses. New methods of vector control are needed and can be achieved by a better understanding of the life cycle of this insect. Embryogenesis is a part of A. aegypty life cycle that is poorly understood. In insects in general and in mosquitoes in particular energetic metabolism is well studied during oogenesis, when the oocyte exhibits fast growth, accumulating carbohydrates, lipids and proteins that will meet the regulatory and metabolic needs of the developing embryo. On the other hand, events related with energetic metabolism during A. aegypti embryogenesis are unknown. RESULTS: Glucose metabolism was investigated throughout Aedes aegypti (Diptera) embryonic development. Both cellular blastoderm formation (CBf, 5 h after egg laying - HAE) and germ band retraction (GBr, 24 HAE) may be considered landmarks regarding glucose 6-phosphate (G6P) destination. We observed high levels of glucose 6-phosphate dehydrogenase (G6PDH) activity at the very beginning of embryogenesis, which nevertheless decreased up to 5 HAE. This activity is correlated with the need for nucleotide precursors generated by the pentose phosphate pathway (PPP), of which G6PDH is the key enzyme. We suggest the synchronism of egg metabolism with carbohydrate distribution based on the decreasing levels of phosphoenolpyruvate carboxykinase (PEPCK) activity and on the elevation observed in protein content up to 24 HAE. Concomitantly, increasing levels of hexokinase (HK) and pyruvate kinase (PK) activity were observed, and PEPCK reached a peak around 48 HAE. Glycogen synthase kinase (GSK3) activity was also monitored and shown to be inversely correlated with glycogen distribution during embryogenesis. CONCLUSIONS: The results herein support the hypothesis that glucose metabolic fate changes according to developmental embryonic stages. Germ band retraction is a moment that was characterized as a landmark in glucose metabolism during Aedes aegypti embryogenesis. Furthermore, the results also suggest a role for GSK3 in glycogen balance/distribution during morphological modifications.


Assuntos
Aedes/embriologia , Aedes/metabolismo , Embrião não Mamífero/metabolismo , Animais , Desenvolvimento Embrionário , Glucose/metabolismo , Glucose-6-Fosfato/metabolismo , Glicólise , Via de Pentose Fosfato
20.
J Vector Ecol ; 45(1): 89-99, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32492277

RESUMO

The richness and abundance of sand fly species were studied in northeastern Brazil in areas of leishmaniasis transmission. The study was carried out in two forest areas with different deforestation times for agricultural and livestock activities: one modified by long-term settlement (more than 50 years of occupation) and another less impacted by short-term settlement (10 years). The sand flies were captured with CDC light traps from 18:00 to 06:00 for three consecutive nights, once a month, from May, 2012 to April, 2014. The study captured 21,708 specimens and also 33 species of Lutzomyia and two of Brumptomyia. Species richness and abundance were higher in the more conserved area of short-term occupation (31 species; 61.7%) than in the more degraded area with long-term occupation (17 species; 38.3%). In the most conserved area, the species richness was higher in the forest fragment than in the rural settlement, whereas in the degraded area the richness was higher in the peri-domicile than in the forest. The diversity was higher in the degraded area forest. There were significant statistical differences when comparing the means of total abundance with the intra-domicile, peri-domicile, and forest environments. The average abundance was statistically higher in the peri-domicile compared to the forest (p = 0.009), but there were no statistically significant differences between intra-domicile-peri-domicile (p = 0.11) and forest-intra-domicile (p = 0.87). In conclusion, a change in vegetation cover negatively affects the richness and abundance of sand flies in the natural environment.


Assuntos
Florestas , Psychodidae/patogenicidade , Animais , Brasil , Ecologia , Clima Tropical
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