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1.
mBio ; 12(2)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785632

RESUMO

The mosquito microbiota is composed of several lineages of microorganisms whose ecological roles and evolutionary histories have yet to be investigated in depth. Among these microorganisms, Asaia bacteria play a prominent role, given their abundance in the gut, reproductive organs, and salivary glands of different mosquito species, while their presence has also been reported in several other insects. Notably, Asaia has great potential as a tool for the control of mosquito-borne diseases. Here, we present a wide phylogenomic analysis of Asaia strains isolated from different species of mosquito vectors and from different populations of the Mediterranean fruit fly (medfly), Ceratitis capitata, an insect pest of worldwide economic importance. We show that phylogenetically distant lineages of Asaia experienced independent genome reductions, despite following a common pattern, characterized by the early loss of genes involved in genome stability. This result highlights the role of specific metabolic pathways in the symbiotic relationship between Asaia and the insect host. Finally, we discovered that all but one of the Asaia strains included in the study possess the pyrethroid hydrolase gene. Phylogenetic analysis revealed that this gene is ancestral in Asaia, strongly suggesting that it played a role in the establishment of the symbiotic association between these bacteria and the mosquito hosts. We propose that this gene from the symbiont contributed to initial pyrethroid resistance in insects harboring Asaia, also considering the widespread production of pyrethrins by several plants.IMPORTANCE We have studied genome reduction within several strains of the insect symbiont Asaia isolated from different species/strains of mosquito and medfly. Phylogenetically distant strains of Asaia, despite following a common pattern involving the loss of genes related to genome stability, have undergone independent genome reductions, highlighting the peculiar role of specific metabolic pathways in the symbiotic relationship between Asaia and its host. We also show that the pyrethroid hydrolase gene is present in all the Asaia strains isolated except for the South American malaria vector Anopheles darlingi, for which resistance to pyrethroids has never been reported, suggesting a possible involvement of Asaia in determining resistance to insecticides.

2.
Sci Rep ; 10(1): 22190, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33335128

RESUMO

Multiple sclerosis is an autoimmune disease that affects the myelinated central nervous system (CNS) neurons and triggers physical and cognitive disabilities. Conventional therapy is based on disease-modifying drugs that control disease severity but can also be deleterious. Complementary medicines have been adopted and evidence indicates that yeast supplements can improve symptoms mainly by modulating the immune response. In this investigation, we evaluated the therapeutic potential of Saccharomyces cerevisiae and its selenized derivative (Selemax) in experimental autoimmune encephalomyelitis (EAE). Female C57BL/6 mice submitted to EAE induction were orally supplemented with these yeasts by gavage from day 0 to day 14 after EAE induction. Both supplements determined significant reduction in clinical signs concomitantly with diminished Th1 immune response in CNS, increased proportion of Foxp3+ lymphocytes in inguinal and mesenteric lymph nodes and increased microbiota diversity. However, Selemax was more effective clinically and immunologically; it reduced disease prevalence more sharply, increased the proportion of CD103+ dendritic cells expressing high levels of PD-L1 in mesenteric lymph nodes and reduced the intestinal inflammatory process more strongly than S. cerevisiae. These results suggest a clear gut-brain axis modulation by selenized S. cerevisiae and suggest their inclusion in clinical trials.

3.
Mol Phylogenet Evol ; 151: 106896, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32562821

RESUMO

The reconstruction of relationships within recently radiated groups is challenging even when massive amounts of sequencing data are available. The use of restriction site-associated DNA sequencing (RAD-Seq) to this end is promising. Here, we assessed the performance of RAD-Seq to infer the species-level phylogeny of the rapidly radiating genus Cereus (Cactaceae). To examine how the amount of genomic data affects resolution in this group, we used datasets and implemented different analyses. We sampled 52 individuals of Cereus, representing 18 of the 25 species currently recognized, plus members of the closely allied genera Cipocereus and Praecereus, and other 11 Cactaceae genera as outgroups. Three scenarios of permissiveness to missing data were carried out in iPyRAD, assembling datasets with 30% (333 loci), 45% (1440 loci), and 70% (6141 loci) of missing data. For each dataset, Maximum Likelihood (ML) trees were generated using two supermatrices, i.e., only SNPs and SNPs plus invariant sites. Accuracy and resolution were improved when the dataset with the highest number of loci was used (6141 loci), despite the high percentage of missing data included (70%). Coalescent trees estimated using SVDQuartets and ASTRAL are similar to those obtained by the ML reconstructions. Overall, we reconstruct a well-supported phylogeny of Cereus, which is resolved as monophyletic and composed of four main clades with high support in their internal relationships. Our findings also provide insights into the impact of missing data for phylogeny reconstruction using RAD loci.

4.
J Venom Anim Toxins Incl Trop Dis ; 26: e20200004, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32518557

RESUMO

Background: The nutritional requirements of honeybees (Apis mellifera) for their complete development need to be supplied through food sources available in the environment, since honeybees are insects that depend directly on blossoming food sources. However, at certain times a food-supply reduction can promote nutritional stress, thus necessitating food supplementation for maintenance or production stimulus of the colonies. Thus, the determination of optimal energy supplementation can assist in the maintenance and production of colonies. Methods: Twenty Apis mellifera beehives were used (with five beehives per treatment): CTL, control (without feeding); SJ, sugarcane juice; SS, sugar syrup; and IS, inverted sucrose. We evaluated the food consumption, population development, and physiological state (expression of vitellogenin and hexamerin 70a genes) of each colony. Results: The results showed that the supplementation of colonies with sugar syrup resulted in an intermediate consumption level (894.6 ± 291 mL) and better development (384.9 ± 237.3 and 158.3 ± 171.6 cm2, sealed and open brood, respectively). Furthermore, this diet ensured that the colonies were in a good physiological state, as bees fed this diet presented the highest relative expression levels of vitellogenin and hexamerin 70a among all the diets tested. Conclusions: Therefore, sugar syrup is concluded to be the best artificial energetic food for use in the supplementation of honeybee colonies.

5.
J. venom. anim. toxins incl. trop. dis ; 26: e20200004, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1135153

RESUMO

The nutritional requirements of honeybees (Apis mellifera) for their complete development need to be supplied through food sources available in the environment, since honeybees are insects that depend directly on blossoming food sources. However, at certain times a food-supply reduction can promote nutritional stress, thus necessitating food supplementation for maintenance or production stimulus of the colonies. Thus, the determination of optimal energy supplementation can assist in the maintenance and production of colonies. Methods: Twenty Apis mellifera beehives were used (with five beehives per treatment): CTL, control (without feeding); SJ, sugarcane juice; SS, sugar syrup; and IS, inverted sucrose. We evaluated the food consumption, population development, and physiological state (expression of vitellogenin and hexamerin 70a genes) of each colony. Results: The results showed that the supplementation of colonies with sugar syrup resulted in an intermediate consumption level (894.6 ± 291 mL) and better development (384.9 ± 237.3 and 158.3 ± 171.6 cm2, sealed and open brood, respectively). Furthermore, this diet ensured that the colonies were in a good physiological state, as bees fed this diet presented the highest relative expression levels of vitellogenin and hexamerin 70a among all the diets tested. Conclusions: Therefore, sugar syrup is concluded to be the best artificial energetic food for use in the supplementation of honeybee colonies.(AU)

6.
Sci Rep ; 9(1): 15492, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664152

RESUMO

Aedes aegypti is the most synanthropic and anthropophilic mosquito of Culicidae. This species always cohabits with humans and is extremely opportunistic. Vector dispersal is directly related to the ability of the females on successfully finding a mate in a generally patchy urban scenario. In the present work, we investigate transcriptional changes in Ae. aegypti females during the courtship process and after mating. We observe a substantial alteration in gene expression triggered just upon contact with Ae. aegypti males, which in turn was not fully correlated to the changes triggered by the contact. After analysing shared significant differentially regulated genes between conspecific contact and insemination, the major part of the observed transcriptomic change triggered by contact is reversed after mating, indicating an intermediary situation between naive and mating conditions that we hypothesize to be crucial for mating success. Upon contact, several chemosensory related genes are repressed, especially odorant binding proteins. Most of these genes return to higher expression rates after mating. None of these genes are significantly regulated by the encounter of a different species, Aedes albopictus. The results presented here might be applied to an innovative control approach focusing on the semiochemical systems of mosquitoes in an effort to disrupt undesirable host-insect interaction to reduce the risk of pathogen transmission to humans.


Assuntos
Aedes/fisiologia , Perfilação da Expressão Gênica , Comportamento Sexual Animal , Animais , Feminino , Masculino , Mosquitos Vetores
7.
PLoS One ; 14(10): e0223277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31581227

RESUMO

Lutzomyia longipalpis is the main vector of Leishmania infantum, the causative agent of visceral leishmaniasis in the Neotropical realm. Its taxonomic status has been widely discussed once it encompasses a complex of species. The knowledge about the genetic structure of insect vector populations helps the elucidation of components and interactions of the disease ecoepidemiology. Thus, the objective of this study was to genotypically analyze populations of the Lu. longipalpis complex from a macrogeographic perspective using Next Generation Sequencing. Polymorphism analysis of three molecular markers was used to access the levels of population genetic structure among nine different populations of sand flies. Illumina Amplicon Sequencing Protocol® was used to identify possible polymorphic sites. The library was sequenced on paired-end Illumina MiSeq platform. Significant macrogeographical population differentiation was observed among Lu. longipalpis populations via PCA and DAPC analyses. Our results revealed that populations of Lu. longipalpis from the nine municipalities were grouped into three clusters. In addition, it was observed that the levels of Lu. longipalpis population structure could be associated with distance isolation. This new sequencing method allowed us to study different molecular markers after a single sequencing run, and to evaluate population and inter-species differences on a macrogeographic scale.


Assuntos
Estruturas Genéticas , Genética Populacional , Genoma de Inseto , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Psychodidae/genética , Animais , Brasil , Genômica/métodos , Geografia
8.
Parasit Vectors ; 12(1): 242, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101131

RESUMO

BACKGROUND: In the Amazon Basin, Nyssorhynchus (Anopheles) darlingi is the most aggressive and effective malaria vector. In endemic areas, behavioral aspects of anopheline vectors such as host preference, biting time and resting location post blood meal have a key impact on malaria transmission dynamics and vector control interventions. Nyssorhynchus darlingi presents a range of feeding and resting behaviors throughout its broad distribution. METHODS: To investigate the genetic diversity related to biting behavior, we collected host-seeking Ny. darlingi in two settlement types in Acre, Brazil: Granada (~ 20-year-old, more established, better access by road, few malaria cases) and Remansinho (~ 8-year-old, active logging, poor road access, high numbers malaria cases). Mosquitoes were classified by the location of collection (indoors or outdoors) and time (dusk or dawn). RESULTS: Genome-wide SNPs, used to assess the degree of genetic divergence and population structure, identified non-random distributions of individuals in the PCA for both location and time analyses. Although genetic diversity related to behavior was confirmed by non-model-based analyses and FST values, model-based STRUCTURE detected considerable admixture of these populations. CONCLUSIONS: To our knowledge, this is the first study to detect genetic markers associated with biting behavior in Ny. darlingi. Additional ecological and genomic studies may help to understand the genetic basis of mosquito behavior and address appropriate surveillance and vector control.


Assuntos
Anopheles/genética , Mordeduras e Picadas , Comportamento Alimentar , Variação Genética , Animais , Brasil , Ecologia , Feminino , Genoma de Inseto , Genótipo , Geografia , Masculino , Controle de Mosquitos , Polimorfismo de Nucleotídeo Único
9.
Genome Biol Evol ; 11(1): 1-10, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30476071

RESUMO

Symbiosis is now recognized as a driving force in evolution, a role that finds its ultimate expression in the variety of associations bonding insects with microbial symbionts. These associations have contributed to the evolutionary success of insects, with the hosts acquiring the capacity to exploit novel ecological niches, and the symbionts passing from facultative associations to obligate, mutualistic symbioses. In bacterial symbiont of insects, the transition from the free-living life style to mutualistic symbiosis often resulted in a reduction in the genome size, with the generation of the smallest bacterial genomes thus far described. Here, we show that the process of genome reduction is still occurring in Asaia, a group of bacterial symbionts associated with a variety of insects. Indeed, comparative genomics of Asaia isolated from different mosquito species revealed a substantial genome size and gene content reduction in Asaia from Anopheles darlingi, a South-American malaria vector. We thus propose Asaia as a novel model to study genome reduction dynamics, within a single bacterial taxon, evolving in a common biological niche.


Assuntos
Acetobacteraceae/genética , Culicidae/microbiologia , Tamanho do Genoma , Genoma Bacteriano , Animais , Feminino , Simbiose
10.
Sci Rep ; 8(1): 9332, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921926

RESUMO

All Plasmodium species express variant antigens which may mediate immune escape in the vertebrate host. In Plasmodium falciparum, the rif gene family encodes variant antigens which are partly exposed on the infected red blood cell surface and may function as virulence factors. Not all rif genes are expressed at the same time and it is unclear what controls rif gene expression. In this work, we addressed global rif transcription using plasmid vectors with two drug resistance markers, one controlled by a rif 5' upstream region and the second by a constitutively active promoter. After spontaneous integration into the genome of one construct, we observed that the resistance marker controlled by the rif 5' upstream region was expressed dependent on the applied drug pressure. Then, the global transcription of rif genes in these transfectants was compared in the presence or absence of drugs. The relative transcript quantities of all rif loci did not change profoundly between strains grown with or without drug. We conclude that either there is no crosstalk between rif loci or that the elusive system of allelic exclusion of rif gene transcription is not controlled by their 5' upstream region alone.


Assuntos
Genoma de Protozoário/genética , Plasmodium falciparum/genética , Regiões Promotoras Genéticas/genética , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia
11.
Alcohol ; 65: 37-43, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29084628

RESUMO

Worldwide, different studies have reported an association of alcohol-use disorder (AUD) with different types of Single Nucleotide Polymorphisms (SNPs) in the genes for aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH). In Brazil, there is little information about the occurrence of these SNPs in the AUD population and an absence of studies characterizing the population in the Central-West Region of Brazil. Actually, in Brazil, there are more than 4 million people with AUD. Despite the major health hazards of AUD, information on alcohol consumption and its consequences are not well understood. Therefore, it is extremely important to characterize these SNPs for the better understanding of AUD as a genetic disease in the Brazilian population. The present study, unlike other studies in other countries, is done with a subject population that shows a significant amount of racial homogenization. We evaluated the presence of SNPs in the ADH (ADH1B, ADH1C, and ADH4) and ALDH (ALDH2) genes in alcohol users of Goiânia, State of Goiás - Brazil, and then we established a possible relationship with AUD by allelic and genotypic study. This study was conducted with a population of people with AUD (n = 99) from Goiás Alcohol Dependence Recovery Center (GO CEREA) and Psychosocial Care Center for Alcohol and Drugs (CAPS AD), and with a population of people without AUD as controls (n = 100). DNA was extracted from whole-blood samples and the genotyping was performed using TaqMan® SNP genotyping assays. For characterization and evaluation of SNPs in the population, genotype frequency, allele frequency, haplotype frequency, Hardy-Weinberg equilibrium, and linkage disequilibrium were analyzed. Statistical analyses were calculated by GENEPOP 4.5 and Haploview software. The allele 1 was considered as "wild" (or *1) and allele 2 as mutant (or *2). Significant differences were found for ADH1B*, ADH4*2, and ALDH2*2 SNPs when the genotype and allele frequencies were analyzed. In addition, four haplotypes were observed between ADH1B*2 and ADH1C*2 through linkage disequilibrium analysis. The genetic variants may be associated with protection against AUD in the population studied.


Assuntos
Álcool Desidrogenase/genética , Alcoólicos , Alcoolismo/genética , Aldeído-Desidrogenase Mitocondrial/genética , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , Aldeído Desidrogenase/genética , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Vigilância da População
12.
Rev Inst Med Trop Sao Paulo ; 59: e39, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28591267

RESUMO

Dogs are considered the main reservoir of Leishmania infantum. This protozoan causes visceral leishmaniasis (VL), an uncontrolled urban zoonosis in Brazil. Serological tests and polymerase chain reaction (PCR) on peripheral blood were performed to identify infected dogs in scenarios of higher and lower prevalence of the disease (Teresina and Vitória). One-hundred infected and 57 non-infected animals from Teresina and 100 non-infected animals from Vitória were studied. Animal selection was not dependent on previous serology. The sensitivity (Teresina) and specificity (Teresina and Vitória) were as follows: indirect antibody fluorescence (IFAT) cut-off of 1:40 (IFAT 1:40): 96%, 18%, and 76%; IFAT 1:80: 90%, 33%, and 93%; direct agglutination test (DAT): 96%, 33%, and 98%; fast agglutination screening test (FAST): 93%, 68%, and 100%; immunochromatographic assay with a recombinant rK39 antigen (rK39): 88%, 74%, and 98%; enzyme linked immunosorbent assay (ELISA): 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®): 98%, 60%, and 98%; and blood PCR: 29%, 93%, and 97%, respectively. In the high transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected dogs. However, in the high transmission city, the area under the receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39, ELISA and TR DPP® was high.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/diagnóstico , Técnicas Imunológicas/métodos , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Feminino , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Programas de Rastreamento , Prevalência , Sensibilidade e Especificidade
13.
Exp Parasitol ; 177: 66-72, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28456690

RESUMO

Standardization of the methods for extraction of DNA from sand flies is essential for obtaining high efficiency during subsequent molecular analyses, such as the new sequencing methods. Information obtained using these methods may contribute substantially to taxonomic, evolutionary, and eco-epidemiological studies. The aim of the present study was to standardize and compare two methods for the extraction of genomic DNA from sand flies for obtaining DNA in sufficient quantities for next-generation sequencing. Sand flies were collected from the municipalities of Campo Grande, Camapuã, Corumbá and Miranda, state of Mato Grosso do Sul, Brazil. Three protocols using a silica column-based commercial kit (ReliaPrep™ Blood gDNA Miniprep System kit, Promega®), and three protocols based on the classical phenol-chloroform extraction method (Uliana et al., 1991), were compared with respect to the yield and quality of the extracted DNA. DNA was quantified using a Qubit 2.0 fluorometer. The presence of sand fly DNA was confirmed by PCR amplification of the IVS6 region (constitutive gene), followed by electrophoresis on a 1.5% agarose gel. A total of 144 male specimens were analyzed, 72 per method. Significant differences were observed between the two methods tested. Protocols 2 and 3 of phenol-chloroform extraction presented significantly better performance than all commercial kit extraction protocols tested. For phenol-chloroform extraction, protocol 3 presented significantly better performance than protocols 1 and 2. The IVS6 region was detected in 70 of 72 (97.22%) samples extracted with phenol, including all samples for protocols 2 and 3. This is the first study on the standardization of methods for the extraction of DNA from sand flies for application to next-generation sequencing, which is a promising tool for entomological and molecular studies of sand flies.


Assuntos
DNA/isolamento & purificação , Técnicas de Genotipagem/métodos , Psychodidae/genética , Análise de Sequência de DNA/métodos , Animais , Distribuição de Qui-Quadrado , Clorofórmio , DNA/química , Endopeptidase K/metabolismo , Técnicas de Genotipagem/normas , Masculino , Fenol , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/normas , Estatísticas não Paramétricas
14.
Parasit Vectors ; 10(1): 76, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28193289

RESUMO

BACKGROUND: In recent decades, throughout the Amazon Basin, landscape modification contributing to profound ecological change has proceeded at an unprecedented rate. Deforestation that accompanies human activities can significantly change aspects of anopheline biology, though this may be site-specific. Such local changes in anopheline biology could have a great impact on malaria transmission. The aim of this study was to investigate population genetics of the main malaria vector in Brazil, Anopheles darlingi, from a microgeographical perspective. METHODS: Microsatellites and ddRADseq-derived single nucleotide polymorphisms (SNPs) were used to assess levels of population genetic structuring among mosquito populations from two ecologically distinctive agricultural settlements (~60 km apart) and a population from a distant (~700 km) urban setting in the western Amazon region of Brazil. RESULTS: Significant microgeographical population differentiation was observed among Anopheles darlingi populations via both model- and non-model-based analysis only with the SNP dataset. Microsatellites detected moderate differentiation at the greatest distances, but were unable to differentiate populations from the two agricultural settlements. Both markers showed low polymorphism levels in the most human impacted sites. CONCLUSIONS: At a microgeographical scale, signatures of genetic heterogeneity and population divergence were evident in Anopheles darlingi, possibly related to local environmental anthropic modification. This divergence was observed only when using high coverage SNP markers.


Assuntos
Anopheles/classificação , Anopheles/crescimento & desenvolvimento , Variação Genética , Genética Populacional , Repetições de Microssatélites , Mosquitos Vetores , Polimorfismo de Nucleotídeo Único , Animais , Anopheles/genética , Brasil , Genótipo
15.
Rev. Inst. Med. Trop. Säo Paulo ; 59: e39, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-842782

RESUMO

ABSTRACT Dogs are considered the main reservoir of Leishmania infantum. This protozoan causes visceral leishmaniasis (VL), an uncontrolled urban zoonosis in Brazil. Serological tests and polymerase chain reaction (PCR) on peripheral blood were performed to identify infected dogs in scenarios of higher and lower prevalence of the disease (Teresina and Vitória). One-hundred infected and 57 non-infected animals from Teresina and 100 non-infected animals from Vitória were studied. Animal selection was not dependent on previous serology. The sensitivity (Teresina) and specificity (Teresina and Vitória) were as follows: indirect antibody fluorescence (IFAT) cut-off of 1:40 (IFAT 1:40): 96%, 18%, and 76%; IFAT 1:80: 90%, 33%, and 93%; direct agglutination test (DAT): 96%, 33%, and 98%; fast agglutination screening test (FAST): 93%, 68%, and 100%; immunochromatographic assay with a recombinant rK39 antigen (rK39): 88%, 74%, and 98%; enzyme linked immunosorbent assay (ELISA): 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®): 98%, 60%, and 98%; and blood PCR: 29%, 93%, and 97%, respectively. In the high transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected dogs. However, in the high transmission city, the area under the receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39, ELISA and TR DPP® was high.


Assuntos
Animais , Masculino , Feminino , Cães , Anticorpos Antiprotozoários/sangue , Doenças do Cão/diagnóstico , Técnicas Imunológicas/métodos , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Brasil/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Programas de Rastreamento , Prevalência , Sensibilidade e Especificidade
16.
Parasit Vectors ; 9(1): 530, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27716392

RESUMO

BACKGROUND: The study of the genetic structure of Aedes aegypti is essential to understanding their population dynamics as well as for the analysis of factors responsible for their resistance and ecological adaptation. The use of molecular markers in identifying differences amongst populations of Ae. aegypti in different geographical areas as well as the temporal variation of the vector populations has contributed to the improvement of vector control strategies. The present study aims to determine the genetic variability of Ae. aegypti populations in a small geographical area (state of Sergipe, Northeastern Brazil) by means of inter-simple sequence repeat (ISSR) and single nucleotide polymorphism (SNP) molecular markers. RESULTS: ISSR markers revealed a more heterogeneous pattern of genetic diversity among the populations with an expected heterozygosity (H E) ranging from 0.261 ± 0.03 to 0.120 ± 0.032, while a similar trend was detected through SNPs across populations with an H E between 0.375 ± 0.054 and 0.269 ± 0.042. The population's genetic differentiation assessed with ISSR and SNP markers indicated a very low structuring among the populations with the highest diversity observed within the populations 72 % (ISSR) and 92 % (SNP). Clustering analysis also suggested little variation among populations: the seven populations were grouped into only three ISSR clusters and a single panmictic group based on SNP markers. The present study identified a close relationship between the populations, which probably results mainly from passive gene flow between mosquitoes from distinct geographic regions, influenced by humans commuting along roads. CONCLUSIONS: There was an intense migration of mosquitos across municipalities, leading to a potential increase in risk of arbovirus and insecticide resistance associated-alleles spreading between mosquito populations.


Assuntos
Aedes/genética , Clima , Variação Genética , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Aedes/fisiologia , Aedes/virologia , Alelos , Distribuição Animal , Migração Animal , Animais , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/prevenção & controle , Febre de Chikungunya/virologia , Dengue/epidemiologia , Dengue/prevenção & controle , Dengue/transmissão , Dengue/virologia , Fluxo Gênico , Humanos , Insetos Vetores/genética , Resistência a Inseticidas/genética , Controle de Mosquitos , Filogeografia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
17.
Biomed Res Int ; 2016: 9249217, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27119085

RESUMO

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) in the Americas with domestic dogs being its major reservoir hosts. The main VL vector is the sandfly Lutzomyia longipalpis, while other Lutzomyia species may play a role in disease transmission. Although the genetic structure of L. infantum populations has been widely evaluated, only a few studies have addressed this subject coupled to the genetic structure of the respective sandfly vectors. In this study, we analyzed the population structure of L. infantum in three major VL endemic areas in Brazil and associated it with Lutzomyia longipalpis geographic structure.


Assuntos
Variação Genética , Haplótipos/genética , Leishmania infantum/genética , Mitocôndrias/genética , Psychodidae/genética , Animais , Brasil , Análise por Conglomerados , DNA Mitocondrial/genética , Geografia , Polimorfismo de Fragmento de Restrição
18.
Can J Vet Res ; 79(4): 279-84, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26424907

RESUMO

Streptococcus suis is an important pathogen in the swine industry. This article is the first to report the occurrence, risk factors, serotype distribution, and antimicrobial susceptibility of S. suis recovered from employees and environmental samples of swine slaughterhouses in Brazil. Tonsillar swabs from all 139 pig-slaughtering employees and 261 environmental swabs were collected for detection of S. suis and serotyping by monoplex and multiplex polymerase chain reaction, respectively. Antimicrobial susceptibility was determined by the disk-diffusion method. Although S. suis was not detected in any of the tested employees, it was isolated from 25% of the environmental samples. Significant differences (P < 0.05) in the occurrence of S. suis were observed between slaughterhouses and between areas of low, medium, and high risk. The most frequent serotypes were 4 and 29, each accounting for 12% of the isolates, followed by 5, 12, 21, and 31, each accounting for 6%. High rates of susceptibility to the antimicrobials doxycycline (100%), ceftiofur (94%), ampicillin (81%), and cephalexin (75%) were observed. However, multidrug resistance was observed in all the isolates. Because S. suis is present in the environment of swine slaughterhouses, on carcasses and knives, as well as on the hands of employees in all areas, all employees are at risk of infection.


Assuntos
Matadouros , Antibacterianos/farmacologia , Sorogrupo , Infecções Estreptocócicas/veterinária , Streptococcus suis/isolamento & purificação , Doenças dos Suínos/microbiologia , Animais , Brasil , Farmacorresistência Bacteriana , Microbiologia Ambiental , Humanos , Exposição Ocupacional , Fatores de Risco , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus suis/classificação , Streptococcus suis/efeitos dos fármacos , Suínos , Doenças dos Suínos/epidemiologia
19.
PLoS One ; 10(6): e0130744, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26106890

RESUMO

Mitochondrial inner membrane uncoupling proteins (UCP) dissipate the proton electrochemical gradient established by the respiratory chain, thus affecting the yield of ATP synthesis. UCP overexpression in plants has been correlated with oxidative stress tolerance, improved photosynthetic efficiency and increased mitochondrial biogenesis. This study reports the main transcriptomic responses associated with the overexpression of an UCP (AtUCP1) in tobacco seedlings. Compared to wild-type (WT), AtUCP1 transgenic seedlings showed unaltered ATP levels and higher accumulation of serine. By using RNA-sequencing, a total of 816 differentially expressed genes between the investigated overexpressor lines and the untransformed WT control were identified. Among them, 239 were up-regulated and 577 were down-regulated. As a general response to AtUCP1 overexpression, noticeable changes in the expression of genes involved in energy metabolism and redox homeostasis were detected. A substantial set of differentially expressed genes code for products targeted to the chloroplast and mainly involved in photosynthesis. The overall results demonstrate that the alterations in mitochondrial function provoked by AtUCP1 overexpression require important transcriptomic adjustments to maintain cell homeostasis. Moreover, the occurrence of an important cross-talk between chloroplast and mitochondria, which culminates in the transcriptional regulation of several genes involved in different pathways, was evidenced.


Assuntos
Regulação da Expressão Gênica de Plantas , Canais Iônicos/biossíntese , Proteínas Mitocondriais/biossíntese , Tabaco/genética , Transcriptoma , Trifosfato de Adenosina/metabolismo , Antioxidantes/metabolismo , Cloroplastos/metabolismo , Perfilação da Expressão Gênica , Homeostase , Mitocôndrias/metabolismo , Oxirredução , Fosforilação Oxidativa , Estresse Oxidativo , Fotossíntese , Plantas Geneticamente Modificadas/genética , RNA/genética , Plântula , Análise de Sequência de RNA , Proteína Desacopladora 1
20.
Parasitol Res ; 114(4): 1541-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25645008

RESUMO

Hepatozoon sp. are parasites that commonly infect frogs and arthropod vectors. This species has variability in the morphological and morphometric characteristics. Due to these variations, the naming of the species is thus impaired and only by visualizing the sporogonic cycle in vector and by molecular studies this problem can be solved. Recently, the use of molecular genetics has helped the species denomination. In this work, we collected 145 frogs (68 Leptodactylus chaquensis and 77 Leptodactylus podicipinus) in different sampling sites, where were found 18 (26.47%) L. chaquensis and 24 (31.17%) L. podicipinus parasitized; besides of gamonts, schizogonic forms were also seen in animals organs. The positivity difference between the collection sites for both frog species was not significant (p = 0.958). Comparing gamonts found in each species of anuran, we observed differences in morphology. The comparison in the molecular level for L. podicipinus was not possible due to small amount of blood obtained, just L. chaquensis had their parasites DNA sequenced. The amplified and sequenced samples, named HEP1 to HEP10, are presented in the phylogenetic tree as a different branch from other haemogregarines described on other hosts. Therefore, we have seen that, although the morphology and morphometry of the collected parasites at each site showed differences, the sequencing of these samples revealed identical species of Hepatozoon, and different compared to those from GenBank, thereby demonstrating that the species of Hepatozoon in L. chaquensis observed in this study probably represent a new species.


Assuntos
Anuros/parasitologia , Coccidiose/veterinária , Eucoccidiida/isolamento & purificação , Animais , Anuros/classificação , Brasil , Coccidiose/parasitologia , Eucoccidiida/classificação , Eucoccidiida/genética , Eucoccidiida/fisiologia , Especificidade de Hospedeiro , Dados de Sequência Molecular , Filogenia
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