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1.
Insect Biochem Mol Biol ; 116: 103259, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31698083

RESUMO

Heliconius butterflies are highly specialized in Passiflora plants, laying eggs and feeding as larvae only on them. Interestingly, both Heliconius butterflies and Passiflora plants contain cyanogenic glucosides (CNglcs). While feeding on specific Passiflora species, Heliconius melpomene larvae are able to sequester simple cyclopentenyl CNglcs, the most common CNglcs in this plant genus. Yet, aromatic, aliphatic, and modified CNglcs have been reported in Passiflora species and they were never tested for sequestration by heliconiine larvae. As other cyanogenic lepidopterans, H. melpomene also biosynthesize the aliphatic CNglcs linamarin and lotaustralin, and their toxicity does not rely exclusively on sequestration. Although the genes encoding the enzymes in the CNglc biosynthesis have not yet been biochemically characterized in butterflies, the cytochromes P450 CYP405A4, CYP405A5, CYP405A6 and CYP332A1 have been hypothesized to be involved in this pathway in H. melpomene. In this study, we determine how the CNglc composition and expression of the putative P450s involved in the biosynthesis of these compounds vary at different developmental stages of Heliconius butterflies. We also establish which kind of CNglcs H. melpomene larvae can sequester from Passiflora. By analysing the chemical composition of the haemolymph from larvae fed with different Passiflora diets, we show that H. melpomene is able to sequestered prunasin, an aromatic CNglcs, from P. platyloba. They are also able to sequester amygdalin, gynocardin, [C13/C14]linamarin and [C13/C14]lotaustralin painted on the plant leaves. The CNglc tetraphyllin B-sulphate from P. caerulea is not detected in the larval haemolymph, suggesting that such modified CNglcs cannot be sequestered by Heliconius. Although pupae and virgin adults contain dihydrogynocardin resulting from larval sequestration, this compound was metabolized during adulthood, and not used as nuptial gift or transferred to the offspring. Thus, we speculate that dihydrogynocardin is catabolized to recycle nitrogen and glucose, and/or to produce fitness signals during courtship. Mature adults have a higher concentration of CNglcs than any other developmental stages due to increased de novo biosynthesis of linamarin and lotaustralin. Accordingly, all CYP405As are expressed in adults, whereas larvae mostly express CYP405A4. Our results shed light on the importance of CNglcs for Heliconius biology and their coevolution with Passiflora.


Assuntos
Borboletas/metabolismo , Glicosídeos/biossíntese , Glicosídeos/metabolismo , Animais , Coevolução Biológica , Borboletas/química , Borboletas/enzimologia , Borboletas/crescimento & desenvolvimento , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Perfilação da Expressão Gênica , Glucosídeos/metabolismo , Herbivoria , Larva/enzimologia , Larva/metabolismo , Estágios do Ciclo de Vida/fisiologia , Nitrilos/metabolismo , Passiflora/química
2.
Rev Soc Bras Med Trop ; 52: e20190020, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31778398

RESUMO

INTRODUCTION: Different blood meal sources can affect biology of triatomines. METHODS: We studied the influence of two different blood meal sources (rabbits and hens) on five biological parameters in Meccus phyllosomus pallidipennis and collected biological parameters. RESULTS: The cohort fed on rabbits had a shorter median life-cycle and lower mortality rate than that fed on hens. Both cohorts required a similar number of blood meals to reach adulthood. Median longevity and number of blood meals for adults were similar between both cohorts. CONCLUSIONS: The studied parameters reflect the high grade of adaptation of M. p. pallidipennis feeding on different hosts.


Assuntos
Comportamento Alimentar/fisiologia , Insetos Vetores/fisiologia , Estágios do Ciclo de Vida/fisiologia , Triatominae/fisiologia , Animais , Doença de Chagas/transmissão , Galinhas , Coelhos
3.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(4): 362-367, 2019 Sep 19.
Artigo em Chinês | MEDLINE | ID: mdl-31612669

RESUMO

OBJECTIVE: To compare the difference of fertility of Biomphalaria glabrata snails between self-fertilization and cross-fertilization and to observe the circadian rhythm of laying eggs, the effect of light on laying eggs and the tolerance of the snail to water and food deficiency, so as to provide the evidence for control and elimination of B. glabrata snails in the field. METHODS: Under laboratory conditions, a single B. glabrata egg for self-fertilization was separated and hatched individually, and young snails were raised in different plastic boxes individually. The eggs for cross-fertilization were hatched and the young snails were fed in the same plastic box. The ability of spawn, the development of the eggs, and the number of snails growing from young to adult snails were compared between the self-fertilization and cross-fertilization. The snails were in the water under four environments, all day illumination, all day without illumination, daytime lighting and night without illumination, and daytime without illumination but night lighting. The eggs were collected and counted daily. The circadian rhythm of spawn and the effect of illumination on spawn were observed. The adult snails were divided into 6 groups and exposed to the environments with relative humidity of 0, 65%, 87% and 100%, respectively. The survival rates of the adult snails exposed to the different environments after different time were observed. The adult snails were placed at 25 °C in the oven to remove water content from the soft body of snails. When the dehydration rates of the soft bodies achieved 10%, 20%, 30%, 40%, 50%, 52%, 55%, 57%, 60%, and 70% respectively, the survival rates of the adult snails exposed to the oven were observed. RESULTS: In the 25 °C water, the average laying egg number for 15 days per snail was (8.77 ± 16.92) eggs/snail in the self-fertilization snail. The average laying egg number for 15 days per snail was (149.71 ± 142.28) eggs/snail in the cross-fertilization snails. There was a significant difference between the self-fertilization snail and cross-fertilization snail (t = 0.999 999, P < 0.01). The hatching rate and reproductive maturation rate of the self-fertilization snails and cross-fertilization snails were 50.1% and 78.9%, and 19.3% and 3.8%, respectively, There was a significant difference (the hatching rate: χ2 = 18.18, P < 0.01, the reproductive maturation rate: χ2 = 11.83, P < 0.01) . In the natural environment of daytime with illumination and nighttime with darkness, the amount of laying 20 eggs of B. glabrata snail was (944.07 ± 392.53) eggs/day during a whole day, among them the amount of laying eggs during daytime account for 10.1% and the amount of laying eggs during nighttime account for 89.9%, and the laying egg was given priority to with the night. The above results suggested that the dark environment was conducive to B. glabrata snails to lay eggs. The above results suggested that light can promote the increase of spawning of B. glabrata. When B. glabrata was exposed to the environments with the relative humidity of 0, 65%, 87% and 100% at 25 °C, respectively, and the longest survival times of snails were 7, 70, 150 d and 100 d, respectively. In the 25 °C water, the snails could survive for 50 days without food. The adult snails were placed at 25 °C in the oven to remove water content from the soft body of snails. When the dehydration rates of the soft bodies achieved 10%, 20%, 30%, 40%, 50%, 52%, 55%, 57%, 60%, and 70% respectively, the survival rates of the adult snails exposed to the oven were 100%, 100%, 100%, 100%, 70%, 30%, 0, 0, 0 and 0, respectively. CONCLUSIONS: B. glabrata can achieve the reproductive process by cross-fertilization or self-fertilization. There is a significant difference in reproductive ability between the cross-fertilization snail and self-fertilization snail, cross-fertilization is stronger than self-fertilization, but the rate of reproduction in the self-fertilization is higher than that in the cross-fertilization. It is indicated that B. glabrata that survive after the dry season plays an important role in the maintenance of local snail populations and transmission of schistosomiasis mansoni.


Assuntos
Biomphalaria , Interações Hospedeiro-Parasita , Schistosoma mansoni , Animais , Biomphalaria/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Estágios do Ciclo de Vida/fisiologia , Reprodução , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/transmissão , Estações do Ano
4.
Ann Parasitol ; 65(3): 193-204, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31578843

RESUMO

Natural transmission of Trypanosoma cruzi to human is established when feces of hematophagous triatomines contaminated with insect-derived from metacyclic trypomastigotes get in contact with the skin, conjunctiva or even oral route. Article is aimed at updating the knowledge about the early interaction between insect-derived metacyclic trypomastigotes at the port of entry and the host. There are few works in the literature describing this first contact between host and natural insect-derived metacyclic trypomastigote. Although it is currently accepted that T. cruzi parasites can penetrate through the lesion left by the insect´s bite, pioneer data do not support this hypothesis as the main via; however, once in the dermis metacyclic trypomastigotes can spread rapidly and likely escape from inoculation site through endothelial cells and disseminate to the body via the bloodstream. A moderate inflammatory reaction took place in the skin at the port of entry within hours, the cytokines induces recruit of neutrophils predominantly, probably because triatomine feces microbiota is present in the inoculum that in some way, its presence modify the progress of the infection.


Assuntos
Doença de Chagas , Células Endoteliais , Estágios do Ciclo de Vida , Trypanosoma cruzi , Animais , Doença de Chagas/patologia , Células Endoteliais/parasitologia , Humanos , Insetos/parasitologia , Estágios do Ciclo de Vida/fisiologia
5.
PLoS Biol ; 17(8): e3000364, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31430281

RESUMO

Many eukaryotic microbes have complex life cycles that include both sexual and asexual phases with strict species specificity. Whereas the asexual cycle of the protistan parasite Toxoplasma gondii can occur in any warm-blooded mammal, the sexual cycle is restricted to the feline intestine. The molecular determinants that identify cats as the definitive host for T. gondii are unknown. Here, we defined the mechanism of species specificity for T. gondii sexual development and break the species barrier to allow the sexual cycle to occur in mice. We determined that T. gondii sexual development occurs when cultured feline intestinal epithelial cells are supplemented with linoleic acid. Felines are the only mammals that lack delta-6-desaturase activity in their intestines, which is required for linoleic acid metabolism, resulting in systemic excess of linoleic acid. We found that inhibition of murine delta-6-desaturase and supplementation of their diet with linoleic acid allowed T. gondii sexual development in mice. This mechanism of species specificity is the first defined for a parasite sexual cycle. This work highlights how host diet and metabolism shape coevolution with microbes. The key to unlocking the species boundaries for other eukaryotic microbes may also rely on the lipid composition of their environments as we see increasing evidence for the importance of host lipid metabolism during parasitic lifecycles. Pregnant women are advised against handling cat litter, as maternal infection with T. gondii can be transmitted to the fetus with potentially lethal outcomes. Knowing the molecular components that create a conducive environment for T. gondii sexual reproduction will allow for development of therapeutics that prevent shedding of T. gondii parasites. Finally, given the current reliance on companion animals to study T. gondii sexual development, this work will allow the T. gondii field to use of alternative models in future studies.


Assuntos
Linoleoil-CoA Desaturase/metabolismo , Toxoplasma/enzimologia , Animais , Gatos , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Intestinos/parasitologia , Estágios do Ciclo de Vida/fisiologia , Ácido Linoleico/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Parasitos/metabolismo , Desenvolvimento Sexual/fisiologia , Especificidade da Espécie , Toxoplasma/crescimento & desenvolvimento , Toxoplasma/patogenicidade
6.
Microb Pathog ; 135: 103610, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31288065

RESUMO

The WRKY transcription factors (TFs) family constitutes a major group of TFs in spermatophytes. Different studies have endorsed the considerable biological roles performed by WRKY TFs in plant growth, biotic and abiotic stress responses. Genomic and transcriptomic profiling facilitate us in understanding the WRKY genes in various plants and reveal how WRKY TFs perform their action in response to different plant stresses. WRKY TFs actively take part in metabolism including carbohydrate synthesis, senescence, and secondary metabolites production. Molecular organization of WRKY TFs in plants highlight most predicted outcome of multiple responses simultaneously. Repression and activation related to W-box and other such elements is controlled at transcriptional, translational and domain level. WRKY TFs are becoming more important in crop improvement because of their binding with downstream elements. Additionally, WRKY proteins intermingle with various other TFs for modulating plant immunity. However, WRKY TFs self-regulation and crosstalk between different signaling pathways using WRKY TFs still need extensive investigations. In this review, we focused characteristics of WRKY TFs in Capsicum annum and related research advancement on their functional involvement in plant responses to the challenges of high temperature stress and pathogens infection. We summarized information about Capsicum annum WRKY TFs on the basis of their functions, their target genes and signaling pathways. Moreover, the mechanisms for synergistic responses to various biotic and abiotic stresses, WRKY target genes and other TFs as well will be of more interest with increments in existing information.


Assuntos
Capsicum/genética , Capsicum/imunologia , Imunidade Inata , Imunidade Vegetal/genética , Imunidade Vegetal/imunologia , Estresse Fisiológico/genética , Estresse Fisiológico/imunologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Umidade , Estágios do Ciclo de Vida/fisiologia , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Metabolismo Secundário , Transdução de Sinais , Temperatura Ambiente , Fatores de Transcrição
7.
FEMS Microbiol Rev ; 43(4): 401-414, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220244

RESUMO

Gametocytes are the only form of the malaria parasite that is transmissible to the mosquito vector. They are present at low levels in blood circulation and significant knowledge gaps exist in their biology. Recent reductions in the global malaria burden have brought the possibility of elimination and eradication, with renewed focus on malaria transmission biology as a basis for interventions. This review discusses recent insights into gametocyte biology in the major human malaria parasite, Plasmodium falciparum and related species.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Malária/parasitologia , Malária/transmissão , Plasmodium/fisiologia , Animais , Culicidae/parasitologia , Humanos , Plasmodium/crescimento & desenvolvimento
8.
BMC Neurosci ; 20(1): 26, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182018

RESUMO

BACKGROUND: Animal responses to thermal stimuli involve intricate contributions of genetics, neurobiology and physiology, with temperature variation providing a pervasive environmental factor for natural selection. Thermal behavior thus exemplifies a dynamic trait that requires non-trivial phenotypic summaries to appropriately capture the trait in response to a changing environment. To characterize the deterministic and plastic components of thermal responses, we developed a novel micro-droplet assay of nematode behavior that permits information-dense summaries of dynamic behavioral phenotypes as reaction norms in response to increasing temperature (thermal tolerance curves, TTC). RESULTS: We found that C. elegans TTCs shift predictably with rearing conditions and developmental stage, with significant differences between distinct wildtype genetic backgrounds. Moreover, after screening TTCs for 58 C. elegans genetic mutant strains, we determined that genes affecting thermosensation, including cmk-1 and tax-4, potentially play important roles in the behavioral control of locomotion at high temperature, implicating neural decision-making in TTC shape rather than just generalized physiological limits. However, expression of the transient receptor potential ion channel TRPA-1 in the nervous system is not sufficient to rescue rearing-dependent plasticity in TTCs conferred by normal expression of this gene, indicating instead a role for intestinal signaling involving TRPA-1 in the adaptive plasticity of thermal performance. CONCLUSIONS: These results implicate nervous system and non-nervous system contributions to behavior, in addition to basic cellular physiology, as key mediators of evolutionary responses to selection from temperature variation in nature.


Assuntos
Adaptação Fisiológica/fisiologia , Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/fisiologia , Canais Iônicos/fisiologia , Locomoção/fisiologia , Canal de Cátion TRPA1/fisiologia , Sensação Térmica/fisiologia , Adaptação Fisiológica/genética , Animais , Proteínas de Caenorhabditis elegans/biossíntese , Proteínas de Caenorhabditis elegans/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Temperatura Alta , Canais Iônicos/genética , Estágios do Ciclo de Vida/fisiologia , Mutação , Sistema Nervoso/metabolismo , Canal de Cátion TRPA1/biossíntese
9.
J Immunol Res ; 2019: 6279360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31192265

RESUMO

The avian immune system improves with the development of the lymphoid organs. The chickens' spleen serves as the largest peripheral lymphoid organ, but little immunological research has been conducted on that spleen during postembryonic development. We investigated the blood-spleen barrier (BSB) by developing morphological architecture, resistance to the corpuscular antigen, immunocyte distribution, gene expression levels of TLR2/4 and cytokines in the spleens of hatched chickens of differing ages. Results demonstrated that the resistance of exogenous carbon particles of the BSB improved with the morphological and structural development of the chicken spleens. The cuboidal endothelial cells which lined the sheathed capillaries were gradually visible, and the discontinuous basement membrane was thickened during postembryonic development. There was an increased number of T and B cells and antigen-presenting cells in the chicken spleen between hatching and adulthood. The mRNA expression levels of TLR2/4, IL-2, IFN-γ, and TNF-α were higher two weeks after hatching, but these decreased and remain stable between 21 and 60 days. As the age increased, the BSB developed structurally and functionally. Our findings provide a better understanding of splenic immune function and the pathogenesis of avian immunology in infectious diseases.


Assuntos
Barreira Hematoencefálica/fisiologia , Galinhas/imunologia , Doenças Transmissíveis/imunologia , Células Endoteliais/fisiologia , Estágios do Ciclo de Vida/fisiologia , Doenças das Aves Domésticas/imunologia , Baço/imunologia , Animais , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Imunidade , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
10.
BMC Neurosci ; 20(1): 27, 2019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208328

RESUMO

BACKGROUND: The mosquito Aedes aegypti has a wide variety of sensory pathways that have supported its success as a species as well as a highly competent vector of numerous debilitating infectious pathogens. Investigations into mosquito sensory systems and their effects on behavior are valuable resources for the advancement of mosquito control strategies. Numerous studies have elucidated key aspects of mosquito sensory systems, however there remains critical gaps within the field. In particular, compared to that of the adult form, there has been a lack of studies directed towards the immature life stages. Additionally, although numerous studies have pinpointed specific sensory receptors as well as responding motor outputs, there has been a lack of studies able to monitor both concurrently. RESULTS: To begin filling aforementioned gaps, here we engineered Ae. aegypti to ubiquitously express a genetically encoded calcium indicator, GCaMP6s. Using this strain, combined with advanced microscopy, we simultaneously measured live stimulus-evoked calcium responses in both neuronal and muscle cells with a wide spatial range and resolution. CONCLUSIONS: By coupling in vivo live calcium imaging with behavioral assays we were able to gain functional insights into how stimulus-evoked neural and muscle activities are represented, modulated, and transformed in mosquito larvae enabling us to elucidate mosquito sensorimotor properties important for life-history-specific foraging strategies.


Assuntos
Aedes/genética , Cálcio/fisiologia , Estágios do Ciclo de Vida/fisiologia , Neurônios/fisiologia , Percepção Olfatória/fisiologia , Natação/fisiologia , Animais , Animais Geneticamente Modificados/fisiologia , Larva/fisiologia , Músculos/fisiologia , Optogenética
12.
PLoS Comput Biol ; 15(5): e1006987, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31086369

RESUMO

Evolution of complex multicellular life began from the emergence of a life cycle involving the formation of cell clusters. The opportunity for cells to interact within clusters provided them with an advantage over unicellular life forms. However, what kind of interactions may lead to the evolution of multicellular life cycles? Here, we combine evolutionary game theory with a model for the emergence of multicellular groups to investigate how cell interactions can influence reproduction modes during the early stages of the evolution of multicellularity. In our model, the presence of both cell types is maintained by stochastic phenotype switching during cell division. We identify evolutionary optimal life cycles as those which maximize the population growth rate. Among all interactions captured by two-player games, the vast majority promotes two classes of life cycles: (i) splitting into unicellular propagules or (ii) fragmentation into two offspring clusters of equal (or almost equal) size. Our findings indicate that the three most important characteristics, determining whether multicellular life cycles will evolve, are the average performance of homogeneous groups, heterogeneous groups, and solitary cells.


Assuntos
Comunicação Celular/fisiologia , Estágios do Ciclo de Vida/fisiologia , Animais , Evolução Biológica , Divisão Celular , Simulação por Computador , Teoria do Jogo , Humanos , Estágios do Ciclo de Vida/genética , Modelos Biológicos , Fenótipo , Reprodução
13.
PLoS Negl Trop Dis ; 13(3): e0007182, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30849124

RESUMO

BACKGROUND: Scabies is a common dermatological condition, affecting more than 130 million people at any time. To evaluate and/or predict the effectiveness and cost-effectiveness of scabies interventions, disease transmission modelling can be used. OBJECTIVE: To review published scabies models and data to inform the design of a comprehensive scabies transmission modelling framework to evaluate the cost-effectiveness of scabies interventions. METHODS: Systematic literature search in PubMed, Medline, Embase, CINAHL, and the Cochrane Library identified scabies studies published since the year 2000. Selected papers included modelling studies and studies on the life cycle of scabies mites, patient quality of life and resource use. Reference lists of reviews were used to identify any papers missed through the search strategy. Strengths and limitations of identified scabies models were evaluated and used to design a modelling framework. Potential model inputs were identified and discussed. FINDINGS: Four scabies models were published: a Markov decision tree, two compartmental models, and an agent-based, network-dependent Monte Carlo model. None of the models specifically addressed crusted scabies, which is associated with high morbidity, mortality, and increased transmission. There is a lack of reliable, comprehensive information about scabies biology and the impact this disease has on patients and society. DISCUSSION: Clinicians and health economists working in the field of scabies are encouraged to use the current review to inform disease transmission modelling and economic evaluations on interventions against scabies.


Assuntos
Análise Custo-Benefício , Sarcoptes scabiei/crescimento & desenvolvimento , Escabiose/economia , Escabiose/transmissão , Animais , Antiparasitários/economia , Antiparasitários/uso terapêutico , Árvores de Decisões , Humanos , Ivermectina/economia , Ivermectina/uso terapêutico , Estágios do Ciclo de Vida/efeitos dos fármacos , Estágios do Ciclo de Vida/fisiologia , Método de Monte Carlo , Anos de Vida Ajustados por Qualidade de Vida , Sarcoptes scabiei/efeitos dos fármacos , Sarcoptes scabiei/fisiologia , Escabiose/tratamento farmacológico , Escabiose/mortalidade
14.
Dev Dyn ; 248(5): 337-350, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884004

RESUMO

BACKGROUND: Mahi-mahi (Coryphaena hippurus) is a commercially and ecologically important fish species that is widely distributed in tropical and subtropical waters. Biological attributes and reproductive capacities of mahi-mahi make it a tractable model for experimental studies. In this study, life development of cultured mahi-mahi from the zygote stage to adult has been described. RESULTS: A comprehensive developmental table has been created reporting development as primarily detailed observations of morphology. Additionally, physiological, behavioral, and molecular landmarks have been described to significantly contribute in the understanding of mahi life development. CONCLUSION: Remarkably, despite the vast difference in adult size, many developmental landmarks of mahi map quite closely onto the development and growth of Zebrafish and other warm-water, active Teleost fishes.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Perciformes/crescimento & desenvolvimento , Animais , Comportamento Animal , Domesticação , Peixes , Larva/crescimento & desenvolvimento , Fenótipo , Reprodução
15.
Adv Parasitol ; 103: 1-10, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30878054

RESUMO

The origin of worms, which were occasionally excreted by some individuals, has left humans wondering for centuries. The story of the gradual discovery of the life cycles of the parasitic helminths is a fascinating one, peppered with misconceptions, misguided by dogmas of the church and enlightened by brave men, who did not recant when they were attacked by the opinion leaders of their time. This article will try to pinpoint some of the key discoveries which turned out to be milestones for the elucidation of the secret life of helminths.


Assuntos
Helmintos/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Parasitologia/história , Animais , História do Século XVIII , História do Século XIX , História do Século XX , Humanos
16.
Parasitol Res ; 118(5): 1445-1456, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30919063

RESUMO

Digenean parasites feature a series of stages with a distinct appearance, reproduction mode, and lifestyle that together constitute their well-known, complex life cycle. Species descriptions of Digenea have always been based on one of these stages-the marita, or sexually reproducing adult in the final host. However, in some cases, data on the life cycle are essential for the differential diagnosis of closely related species. Here, we present the case of Notocotylus atlanticus, where different stages of its life cycle were discovered for the first time since the species description, and across the Atlantic. We used a material from a naturally infected intertidal marine snail, Ecrobia ventrosa, and several waterfowl species and also carried out infection experiments. For morphological studies, we employed light microscopy, SEM, and CLSM; molecular data obtained include sequences of ITS1 and 28S rRNA gene. We demonstrate that N. atlanticus adult worm morphology is barely sufficient to distinguish it from several other species. Cercariae morphology and identity of the first intermediate hosts provide crucial additional information. According to our preliminary phylogenetic reconstructions, two notocotylid lineages are associated with two major gastropod lineages-the Caenogastropoda and the Heterobranchia. The traditional character to identify notocotylid genera (structure of ventral organs) fails to explain the phylogeny and thus requires reassessment. Further reliable morphological, life cycle and molecular data on other species are likely to reveal more patterns in notocotylid systematics, host specificity, and evolution.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Caramujos/parasitologia , Trematódeos/classificação , Trematódeos/crescimento & desenvolvimento , Animais , Cercárias/genética , DNA Intergênico/genética , Especificidade de Hospedeiro , Filogenia , RNA Ribossômico 28S/genética , Trematódeos/genética
17.
An Acad Bras Cienc ; 91(1): e20171039, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30916154

RESUMO

The cnidae are the exclusive diagnostic structures of phylum Cnidaria. The inventory of all cnidae types of a particular species is called the cnidom. The study of cnidae has been widely addressed in all classes of cnidarians. Particularly in the order Actiniaria (sea anemones), the study of the composition, size and distribution of cnidae is essential to the identification and description of species. In the present study, we examine the cnidom of the sea anemone Aulactinia marplatensis in three different stages of development throughout its life cycle. We found that the composition and abundance patterns are very similar between the adult and juvenile stages, although significant differences in the size capsules were found between both stages and in all cnidae types observed, being bigger those from the adult forms. The planula larvae stage presents a less diverse cnidom in comparison to the juvenile and adult stages; however, it presents an exclusive cnidae type (the mesobasic p-mastigophore) which is the biggest in size of all the cnidae types observed in the species. These results highlight the importance of considering the stage of development when cnidae is used as a diagnostic character, and the particular relevance of the study of the cnidom in larval stages.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Anêmonas-do-Mar/crescimento & desenvolvimento , Animais , Larva/fisiologia , Filogenia , Anêmonas-do-Mar/classificação , Anêmonas-do-Mar/genética
18.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30900722

RESUMO

Japanese beetle, Popillia japonica (Newman), is a severe invasive insect pest of turf, landscapes, and horticultural crops. It has successfully colonized much of the United States and has recently established in mainland Europe. The distribution and voltinism of P. japonica will undoubtedly change as a consequence of climate change, posing additional challenges to the management of this species. To assess these challenges, a process-oriented bioclimatic niche model for P. japonica was developed to examine its potential global distribution under current (1981-2010) and projected climatic conditions (2040-2059) using one emission scenario (representative concentration pathway [RCP] 8.5) and two global climate models, ACCESS1-0 and CNRM-CM5. Under current climatic conditions, the bioclimatic niche model agreed well with all credible distribution data. Model projections indicate a strong possibility of further range expansion throughout mainland Europe under both current and future climates. In North America, projected increases in temperature would enable northward range expansion across Canada while simultaneously shifting southern range limits in the United States. In Europe, the suitable range for P. japonica would increase by 23% by midcentury, especially across portions of the United Kingdom, Ireland, and Scandinavia. Under the RCP 8.5 scenario, cumulative growing degree-days increased, thereby reducing the probability of biannual life cycles in northern latitudes where they can occur, including Hokkaido, Japan, northeastern portions of the United States, and southern Ontario, Canada. The results of this study highlight several regions of increasing and emerging risk from P. japonica that should be considered routinely in ongoing biosecurity and pest management surveys.


Assuntos
Distribuição Animal/fisiologia , Mudança Climática , Besouros/fisiologia , Espécies Introduzidas/tendências , Animais , Besouros/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia
19.
Parasitol Res ; 118(5): 1501-1509, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859312

RESUMO

Trematodes of the genus Philophthalmus are cosmopolitan parasites that infect the eyes of birds and mammals. They have the potential to affect the survival of their hosts and a few cases of human philophthalmiasis have occurred worldwide. Adults of known Philophthalmus species have never been recorded from bird hosts in New Zealand, despite their cercarial stage being a focus of various studies. Here, we describe a new species of Philophthalmus infecting New Zealand red-billed and black-backed gulls, Philophthalmus attenuatus n. sp. It is distinguished from other marine species of Philophthalmus by its long, thin body shape, consistently longer vitelline field on the left, and its body reflexed at the ventral sucker. We use molecular methods to complete the life cycle of this species, matching it with the larval stage infecting the mud whelk, Zeacumantus subcarinatus, and present a preliminary cox1 phylogeny. In addition, we comment on the validity of some taxonomic characters used to differentiate species of this genus, discuss potential colonisation routes to New Zealand and comment on the potential for zoonotic infection.


Assuntos
Charadriiformes/parasitologia , Olho/parasitologia , Gastrópodes/parasitologia , Estágios do Ciclo de Vida/fisiologia , Trematódeos/classificação , Trematódeos/crescimento & desenvolvimento , Infecções por Trematódeos/veterinária , Animais , Aves/parasitologia , Cercárias/crescimento & desenvolvimento , Larva , Nova Zelândia , Trematódeos/genética
20.
Molecules ; 24(4)2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795632

RESUMO

Chemotherapy is limited in the treatment of leishmaniasis due to the toxic effects of drugs, low efficacy of alternative treatments, and resistance of the parasite. This work assesses the in vitro activity of flavopereirine on promastigote cultures of Leishmania amazonensis. In addition, an in silico evaluation of the physicochemical characteristics of this alkaloid is performed. The extract and fractions were characterized by thin-layer chromatography and HPLC-DAD, yielding an alkaloid identified by NMR. The antileishmanial activity and cytotoxicity were assayed by cell viability test (MTT). The theoretical molecular properties were calculated on the Molinspiration website. The fractionation made it possible to isolate a beta-carboline alkaloid (flavopereirine) in the alkaloid fraction. Moreover, it led to obtaining a fraction with greater antileishmanial activity, since flavopereirine is very active. Regarding the exposure time, a greater inhibitory effect of flavopereirine was observed at 24 h and 72 h (IC50 of 0.23 and 0.15 µg/mL, respectively). The extract, fractions, and flavopereirine presented low toxicity, with high selectivity for the alkaloid. Furthermore, flavopereirine showed no violation of Lipinski's rule of five, showing even better results than the known inhibitor of oligopeptidase B, antipain, with three violations. Flavopereirine also interacted with residue Tyr-499 of oligopeptidase B during the molecular dynamics simulations, giving a few insights of a possible favorable mechanism of interaction and a possible inhibitory pathway. Flavopereirine proved to be a promising molecule for its antileishmanial activity.


Assuntos
Antiprotozoários/farmacologia , Apocynaceae/química , Carbolinas/farmacologia , Alcaloides Indólicos/isolamento & purificação , Leishmania mexicana/efeitos dos fármacos , Proteínas de Protozoários/antagonistas & inibidores , Serina Endopeptidases/química , Antipaína/química , Antipaína/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Carbolinas/química , Carbolinas/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/classificação , Concentração Inibidora 50 , Leishmania mexicana/crescimento & desenvolvimento , Estágios do Ciclo de Vida/efeitos dos fármacos , Estágios do Ciclo de Vida/fisiologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Casca de Planta/química , Extratos Vegetais/química , Proteínas de Protozoários/química , Células THP-1
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