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1.
J Water Health ; 18(6): 983-994, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33328369

RESUMO

Fish farming can have a negative impact on water quality and aquatic organisms due to emerging blooms of Cyanobacteria and the production of cyanotoxins. In this study, the effect of aquaculture in hydroelectric reservoirs in Brazil was evaluated in six fish farms and in upstream and downstream water through analysis of the microbiome, Cyanobacteria and microcystin concentrations. Synechococcus and Microcystis were observed at all six locations, while Limnothrix was also observed abundantly at two locations. An increase in the relative abundance of Cyanobacteria inside the fish farms was observed at two locations, while an increase of Cyanobacteria was observed in downstream at five of the six locations. Microcystins were detected in significant and high values in all locations, with concentrations up to 1.59 µg/L. The trend in microcystin concentrations was mirrored in copy numbers of the mcyE gene (encodes microcystin synthetase) and presence of Microcystis, but not in any of the other observed cyanobacterial groups. In summary, the study shows that aquaculture production influenced the water microbiome inside and downstream the fish farms, and a direct correlation was found between mcyE gene copies, microcystin production and abundance of Microcystis, but not for the total abundance of Cyanobacteria.


Assuntos
Cianobactérias , Microcystis , Brasil , Cianobactérias/genética , Pesqueiros , Microcistinas , Microcystis/genética
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.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
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
12.
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
13.
Rev. bras. ciênc. vet ; 23(3-4): 163-167, jul./dez. 2016. il.
Artigo em Português | LILACS | ID: biblio-987483

RESUMO

Objetivou-se com este estudo pesquisar infecção natural de equídeos por Leishmania sp em área endêmica de leishmaniose tegumentar americana de Teresina, Piauí, Brasil. As leishmanioses são causadas por protozoário hemoflagelado, intracelular integrante do gênero Leishmania. Clinicamente observa-se uma variedade de sinais desde lesões cutâneas até formas viscerotrópicas que são mais graves e potencialmente fatais. Constituem grande problema de saúde pública mundial. O cão é considerado o principal reservatório doméstico de leishmaniose visceral americana (LVA). No peridomicílio de moradias rurais, os equídeos, embora com menor relevância que os canídeos, podem se transformar em importante hospedeiro para este parasito. Coletou-se sangue periférico de 42 equídeos para pesquisa de DNA de leishmânia spp através da técnica de "nested" reação em cadeia de polimerase (PCR) com oligonucleotídeos flanqueando a região ribossomal internal transcribed spacer 1 (ITS'1). A confirmação da espécie foi realizada pela digestão do produto amplificado com enzima de restrição Hae III. Os animais não apresentavam sinal clínico sugestivo de nenhuma patologia, entretanto 21 (50%) foram PCR positivos para leishmaniose (14 equinos, quatro asininos e três muares). A digestão do produto da "nested" PCR permitiu identificar sequências de DNA de Leishmania (Leishmania) infantum, caracterizando a infecção como leishmaniose visceral americana (LVA). A presença de equídeos infectados com Leishmania (Leishmania) infantum sugere sua participação no ciclo de transmissão da leishmaniose visceral em Teresina, Piauí, Brasil.


This study aims to research natural Leishmania sp equine infection in an endemic American Tegumentary Leishmaniasis area of Teresina City, Piauí State, Brazil. Leishmania are caused by intracellular hemoflagellate protozoa of the gender Leishmania. Clinically we can observe a variety of signals since cutaneous injuries until viscerotropic types which are more severe and potentially fatal. They constitute a great worldwide public health problem. The dog is considered the main domestic reservoir of American Visceral Leishmaniasis (AVL). In the peridomicile of rural abodes, the equines, although with less relevance than canines, may become an important host for this parasite. Peripheral blood was collected from 42 equines for DNA research of leishmania spp through the technique of "nested" PCR with oligonucleotides flanking the region ITS'1. The confirmation of the species was performed by the digestion of the amplified product with restriction enzyme Hae III. The animals did not present any suggestive clinical pathology signal, however, 21 (50%) were PCR positive for Leishmaniasis (14 equines, four donkeys and three mules). The digestion of the product from "nested" PCR permitted to identify DNA sequences of Leishmania (Leishmania) infantum, characterizing the infection as American Visceral Leishmaniasis (AVL). The presence of infected equines with Leishmania (Leishmania) infantun suggests their participation in the cycle of visceral Leishmaniasis transmission in Teresina City, Piauí State, Brazil.


Assuntos
Animais , Parasitologia , Doenças Endêmicas , Cavalos
14.
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
15.
Environ Toxicol Chem ; 34(5): 1062-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25703042

RESUMO

Bees play a crucial role in pollination and generate honey and other hive products; therefore, their worldwide decline is cause for concern. New broad-spectrum systemic insecticides such as fipronil can harm bees and their use has been discussed as a potential threat to bees' survival. In the present study, the authors evaluate the in vitro toxicity of fipronil and note behavioral and motor activity changes in Africanized adult Apis mellifera that ingest or come into contact with lethal or sublethal doses of fipronil. The effects of sublethal doses on brood viability, population growth, behavior, and the expression of the defensin 1 gene in adult bees were studied in colonies fed with contaminated sugar syrup (8 µg fipronil L(-1) ). Fipronil is highly toxic to bees triggering agitation, seizures, tremors, and paralysis. Bees that are exposed to a lethal or sublethal doses showed reduced motor activity. The number of eggs that hatched, the area occupied by worker eggs, and the number of larvae and pupae that developed were reduced, adult bees showed lethargy, and colonies were abandoned when they were exposed to sublethal doses of fipronil. No change was seen in the bees' expression of defensin 1. The authors conclude that fipronil is highly toxic to honey bees and even sublethal doses may negatively affect the development and maintenance of colonies.


Assuntos
Abelhas/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Inseticidas/toxicidade , Atividade Motora/efeitos dos fármacos , Pirazóis/toxicidade , Animais , Abelhas/crescimento & desenvolvimento , Abelhas/metabolismo , Defensinas/genética , Defensinas/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Pupa/metabolismo
16.
Rev Soc Bras Med Trop ; 47(5): 593-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25467261

RESUMO

INTRODUCTION: Kala-azar is a disease resulting from infection by Leishmania donovani and Leishmania infantum. Most patients with the disease exhibit prolonged fever, wasting, anemia and hepatosplenomegaly without complications. However, some patients develop severe disease with hemorrhagic manifestations, bacterial infections, jaundice, and edema dyspnea, among other symptoms, followed by death. Among the parasite molecules that might influence the disease severity are the macrophage migration inhibitory factor-like proteins (MIF1 and MIF2) and N-acetylglucosamine-1-phosphotransferase (NAGT), which act in the first step of protein N-glycosylation. This study aimed to determine whether MIF1, MIF2 and NAGT are virulence factors for severe kala-azar. METHODS: To determine the parasite genotype in kala-azar patients from Northeastern Brazil, we sequenced the NAGT genes of L. infantum from 68 patients as well as the MIF1 and MIF2 genes from 76 different subjects with diverse clinical manifestations. After polymerase chain reaction (PCR), the fragments were sequenced, followed by polymorphism identification. RESULTS: The nucleotide sequencing of the 144 amplicons revealed the absence of genetic variability of the NAGT, MIF1 and MIF2 genes between the isolates. The conservation of these genes suggests that the clinical variability of kala-azar does not depend upon these genes. Additionally, this conservation suggests that these genes may be critical for parasite survival. CONCLUSIONS: NAGT, MIF1 and MIF2 do not alter the severity of kala-azar. NAGT, MIF1 and MIF2 are highly conserved among different isolates of identical species and exhibit potential for use in phylogenetic inferences or molecular diagnosis.


Assuntos
Leishmania infantum/patogenicidade , Leishmaniose Visceral/parasitologia , Fatores Inibidores da Migração de Macrófagos/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Fatores de Virulência/genética , Genótipo , Humanos , Filogenia , Reação em Cadeia da Polimerase , Índice de Gravidade de Doença
17.
Rev. Soc. Bras. Med. Trop ; 47(5): 593-598, Sep-Oct/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-728890

RESUMO

Introduction Kala-azar is a disease resulting from infection by Leishmania donovani and Leishmania infantum. Most patients with the disease exhibit prolonged fever, wasting, anemia and hepatosplenomegaly without complications. However, some patients develop severe disease with hemorrhagic manifestations, bacterial infections, jaundice, and edema dyspnea, among other symptoms, followed by death. Among the parasite molecules that might influence the disease severity are the macrophage migration inhibitory factor-like proteins (MIF1 and MIF2) and N-acetylglucosamine-1-phosphotransferase (NAGT), which act in the first step of protein N-glycosylation. This study aimed to determine whether MIF1, MIF2 and NAGT are virulence factors for severe kala-azar. Methods To determine the parasite genotype in kala-azar patients from Northeastern Brazil, we sequenced the NAGT genes of L. infantum from 68 patients as well as the MIF1 and MIF2 genes from 76 different subjects with diverse clinical manifestations. After polymerase chain reaction (PCR), the fragments were sequenced, followed by polymorphism identification. Results The nucleotide sequencing of the 144 amplicons revealed the absence of genetic variability of the NAGT, MIF1 and MIF2 genes between the isolates. The conservation of these genes suggests that the clinical variability of kala-azar does not depend upon these genes. Additionally, this conservation suggests that these genes may be critical for parasite survival. Conclusions NAGT, MIF1 and MIF2 do not alter the severity of kala-azar. NAGT, MIF1 and MIF2 are highly conserved among different isolates of identical species and exhibit potential for use in phylogenetic inferences or molecular diagnosis. .


Assuntos
Humanos , Leishmania infantum/patogenicidade , Leishmaniose Visceral/parasitologia , Fatores Inibidores da Migração de Macrófagos/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Fatores de Virulência/genética , Genótipo , Filogenia , Reação em Cadeia da Polimerase , Índice de Gravidade de Doença
18.
Mediators Inflamm ; 2014: 230129, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25242866

RESUMO

In visceral leishmaniasis (VL) endemic areas, a minority of infected individuals progress to disease since most of them develop protective immunity. Therefore, we investigated the risk markers of VL within nonimmune sector. Analyzing infected symptomatic and, asymptomatic, and noninfected individuals, VL patients presented with reduced high-density lipoprotein cholesterol (HDL-C), elevated triacylglycerol (TAG), and elevated very-low-density lipoprotein cholesterol (VLDL-C) levels. A polymorphism analysis of the lipoprotein lipase (LPL) gene using HindIII restriction digestion (N = 156 samples) (H+ = the presence and H- = the absence of mutation) revealed an increased adjusted odds ratio (OR) of VL versus noninfected individuals when the H+/H+ was compared with the H-/H- genotype (OR = 21.3; 95% CI = 2.32-3335.3; P = 0.003). The H+/H+ genotype and the H+ allele were associated with elevated VLDL-C and TAG levels (P < 0.05) and reduced HDL-C levels (P < 0.05). An analysis of the L162V polymorphism in the peroxisome proliferator-activated receptor alpha (PPARα) gene (n = 248) revealed an increased adjusted OR when the Leu/Val was compared with the Leu/Leu genotype (OR = 8.77; 95% CI = 1.41-78.70; P = 0.014). High TAG (P = 0.021) and VLDL-C (P = 0.023) levels were associated with susceptibility to VL, whereas low HDL (P = 0.006) levels with resistance to infection. The mutated LPL and the PPARα Leu/Val genotypes may be considered risk markers for the development of VL.


Assuntos
Leishmaniose Visceral/sangue , Lipase Lipoproteica/genética , Lipoproteínas HDL/genética , PPAR alfa/genética , Genótipo , Humanos , Leishmaniose Visceral/genética , Lipoproteínas VLDL/sangue , Polimorfismo Genético/genética , Triglicerídeos/sangue
19.
Mem. Inst. Oswaldo Cruz ; 109(3): 379-383, 06/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-711736

RESUMO

An analysis of the dietary content of haematophagous insects can provide important information about the transmission networks of certain zoonoses. The present study evaluated the potential of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial cytochrome B (cytb) gene to differentiate between vertebrate species that were identified as possible sources of sandfly meals. The complete cytb gene sequences of 11 vertebrate species available in the National Center for Biotechnology Information database were digested with Aci I, Alu I, Hae III and Rsa I restriction enzymes in silico using Restriction Mapper software. The cytb gene fragment (358 bp) was amplified from tissue samples of vertebrate species and the dietary contents of sandflies and digested with restriction enzymes. Vertebrate species presented a restriction fragment profile that differed from that of other species, with the exception of Canis familiaris and Cerdocyon thous. The 358 bp fragment was identified in 76 sandflies. Of these, 10 were evaluated using the restriction enzymes and the food sources were predicted for four: Homo sapiens (1), Bos taurus (1) and Equus caballus (2). Thus, the PCR-RFLP technique could be a potential method for identifying the food sources of arthropods. However, some points must be clarified regarding the applicability of the method, such as the extent of DNA degradation through intestinal digestion, the potential for multiple sources of blood meals and the need for greater knowledge regarding intraspecific variations in mtDNA.


Assuntos
Animais , Gatos , Bovinos , Cães , Humanos , Ratos , Comportamento Animal/fisiologia , Citocromos b/genética , Psychodidae/fisiologia , Comportamento Animal/classificação , Comportamento Alimentar/fisiologia , Cavalos , Refeições , Mitocôndrias/enzimologia , Gambás , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Psychodidae/classificação , Suínos
20.
Mem Inst Oswaldo Cruz ; 109(3): 379-83, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24821056

RESUMO

An analysis of the dietary content of haematophagous insects can provide important information about the transmission networks of certain zoonoses. The present study evaluated the potential of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial cytochrome B (cytb) gene to differentiate between vertebrate species that were identified as possible sources of sandfly meals. The complete cytb gene sequences of 11 vertebrate species available in the National Center for Biotechnology Information database were digested with Aci I, Alu I, Hae III and Rsa I restriction enzymes in silico using Restriction Mapper software. The cytb gene fragment (358 bp) was amplified from tissue samples of vertebrate species and the dietary contents of sandflies and digested with restriction enzymes. Vertebrate species presented a restriction fragment profile that differed from that of other species, with the exception of Canis familiaris and Cerdocyon thous. The 358 bp fragment was identified in 76 sandflies. Of these, 10 were evaluated using the restriction enzymes and the food sources were predicted for four: Homo sapiens (1), Bos taurus (1) and Equus caballus (2). Thus, the PCR-RFLP technique could be a potential method for identifying the food sources of arthropods. However, some points must be clarified regarding the applicability of the method, such as the extent of DNA degradation through intestinal digestion, the potential for multiple sources of blood meals and the need for greater knowledge regarding intraspecific variations in mtDNA.


Assuntos
Comportamento Animal/fisiologia , Citocromos b/genética , Psychodidae/fisiologia , Animais , Comportamento Animal/classificação , Gatos , Bovinos , Cães , Comportamento Alimentar/fisiologia , Cavalos , Humanos , Refeições , Mitocôndrias/enzimologia , Gambás , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Psychodidae/classificação , Ratos , Suínos
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