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1.
PLoS Negl Trop Dis ; 13(11): e0007846, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31751335

RESUMO

Angiostrongylus cantonensis (rat lungworm) is the etiological agent of angiostrongyliasis, mainly causing eosinophilic meningitis or meningoencephalitis in human. Although the biology of A. cantonensis is relatively well known, little is understood about the mechanisms of the parasite's development and survival in definitive hosts, or its adaptation to a broad range of snail intermediate hosts. Here, we generate a high-quality assembly of a well-defined laboratory strain of A. cantonensis from Guangzhou, China, by using Illumina and PacBio sequencing technologies. We undertake comparative analyses with representative helminth genomes and explore transcriptomic data throughout key developmental life-cycles of the parasite. We find that part of retrotransposons and gene families undergo multiple waves of expansions. These include extracellular superoxide dismutase (EC-SOD) and astacin-like proteases which are considered to be associated with invasion and survival of the parasite. Furthermore, these paralogs from different sub-clades based on phylogeny, have different expression patterns in the molluscan and rodent stages, suggesting divergent functions under the different parasitic environment. We also find five candidate convergent signatures in the EC-SOD proteins from flukes and one sub-clade of A. cantonensis. Additionally, genes encoding proteolytic enzymes, involved in host hemoglobin digestion, exhibit expansion in A. cantonensis as well as two other blood-feeding nematodes. Overall, we find several potential adaptive evolutionary signatures in A. cantonensis, and also in some other helminths with similar traits. The genome and transcriptomes provide a useful resource for detailed studies of A. cantonensis-host adaptation and an in-depth understanding of the global-spread of angiostrongyliasis.


Assuntos
Adaptação Biológica , Angiostrongylus cantonensis/classificação , Angiostrongylus cantonensis/genética , Evolução Molecular , Genoma Helmíntico , Infecções por Strongylida/parasitologia , Infecções por Strongylida/veterinária , Angiostrongylus cantonensis/isolamento & purificação , Animais , China , Biologia Computacional , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Roedores , Trematódeos
2.
Front Immunol ; 10: 2346, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749791

RESUMO

Macrophages are commonly classified as M1 macrophages or M2 macrophages. The M2 macrophages are further sub-categorized into M2a, M2b, M2c, and M2d subtypes. The M2a, M2b, and M2c subtypes play roles in anti-inflammatory activity, tissue remodeling, type 2 T helper cell (Th2) activation, and immunoregulation. Previous studies have shown that macrophage exosomes can affect some disease processes. Exosomes are 30-150-nm lipid bilayer membrane vesicles derived from most living cells, with important biological functions. The role of exosomes in preventing the development of autoimmune diseases, including inflammatory bowel disease (IBD), has evoked increasing interest. Here, we analyze the roles of exosomes derived from M2a, M2b, and M2c macrophage phenotypes in dextran sulfate sodium (DSS)-induced colitis. Exosomes were isolated from the supernatant of different types of macrophages and identified via transmission electron microscopy (TEM), western blotting, and NanoSight. The results showed that M2b macrophage exosomes significantly attenuated the severity of DSS-induced colitis in mice. The number of regulatory T (Treg) cells in the spleens of mice with colitis and levels of IL-4 both increased following treatment with M2b macrophage exosomes. In addition, key cytokines associated with colitis (IL-1ß, IL-6, and IL-17A) were significantly suppressed, following treatment with M2b macrophage exosomes. The M2b macrophage exosomes exerted protective effects on DSS-induced colitis, mainly mediated by the CC chemokine 1 (CCL1)/CCR8 axis. These findings provide a novel approach for the treatment of IBD.

3.
Gigascience ; 8(10)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634388

RESUMO

BACKGROUND: Achatina fulica, the giant African snail, is the largest terrestrial mollusk species. Owing to its voracious appetite, wide environmental adaptability, high growth rate, and reproductive capacity, it has become an invasive species across the world, mainly in Southeast Asia, Japan, the western Pacific islands, and China. This pest can damage agricultural crops and is an intermediate host of many parasites that can threaten human health. However, genomic information of A. fulica remains limited, hindering genetic and genomic studies for invasion control and management of the species. FINDINGS: Using a k-mer-based method, we estimated the A. fulica genome size to be 2.12 Gb, with a high repeat content up to 71%. Roughly 101.6 Gb genomic long-read data of A. fulica were generated from the Pacific Biosciences sequencing platform and assembled to produce a first A. fulica genome of 1.85 Gb with a contig N50 length of 726 kb. Using contact information from the Hi-C sequencing data, we successfully anchored 99.32% contig sequences into 31 chromosomes, leading to the final contig and scaffold N50 length of 721 kb and 59.6 Mb, respectively. The continuity, completeness, and accuracy were evaluated by genome comparison with other mollusk genomes, BUSCO assessment, and genomic read mapping. A total of 23,726 protein-coding genes were predicted from the assembled genome, among which 96.34% of the genes were functionally annotated. The phylogenetic analysis using whole-genome protein-coding genes revealed that A. fulica separated from a common ancestor with Biomphalaria glabrata ∼182 million years ago. CONCLUSION: To our knowledge, the A. fulica genome is the first terrestrial mollusk genome published to date. The chromosome sequence of A. fulica will provide the research community with a valuable resource for population genetics and environmental adaptation studies for the species, as well as investigations of the chromosome-level of evolution within mollusks.

4.
Front Microbiol ; 10: 2280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636619

RESUMO

Histone deacetylase inhibitor (HDACi) has been used in the treatment of neurodegenerative or autoimmune diseases. Angiostrongyliasis cantonensis caused by Angiostrongylus cantonensis infection is an emerging zoonosis of human eosinophilic meningitis or meningoencephalitis. Progressive neuronal apoptosis is the pathological basis of behavioral dysfunctions in angiostrongyliasis cantonensis. Neurological defects after anthelmintic treatment for angiostrongyliasis cantonensis are still common. In this study, we examined the effects of trichostatin A (TSA), a HDACi, on eosinophilic meningitis induced by A. cantonensis in mice. Intragastric administration of TSA significantly ameliorated brain injury and decreased cognitive impairments in mice at 15 days post-infection. TSA administration effectively reduced the inflammatory factor levels of iNOS, TNF-α, IL-5, IL-6, and IL-13 in infected mice. TSA treatment counteracted apoptosis with reduced expression levels of cleaved caspase-3, -4, -6, and RIP3 in A. cantonensis infected mice. In addition, TSA administration reduced total HDAC activity and increased the acetylation of histone H3 and H4 in the brain tissue of infected mice. The underlying mechanism of TSA on eosinophilic meningitis might be associated with decreased NF-κB p65 nuclear accumulation by inhibiting IκB phosphorylation. Furthermore, a co-expressive network of NF-κB p65 with 22 other genes was constructed according to our previous transcriptomic data in infected mice. We identified the correlations in the gene expression of NF-κB p65 with Lrp10, Il12rb1, Nfkbia, Ube2n, and Ube2d1 in infected mice after TSA administration. Thus, TSA has a protective effect on the progression of eosinophilic meningitis induced by A. cantonensis in mice.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31565062

RESUMO

Background and Aim: The progression of liver fibrosis in chronic hepatitis B (CHB) patients is currently insufficiently controlled worldwide. The Yi Guan Jian decoction (YGJD) has been widely used in the treatment of liver fibrosis in CHB cases. Although animal studies have reported the antifibrotic effects of the decoction, the active ingredients of the YGJD remain unknown. This study aimed at identifying the potential active ingredients and exploring the mechanisms of action (MOA) of the decoction when treating CHB patients with fibrosis. Methods: Using data mining techniques and a structural clustering analysis, the potential active ingredients were determined. A network analysis of the differentially expressed genes was conducted to identify the potential targets. Selected compounds were docked to the potential targets for the compound-target interaction simulation. In vitro validation, including a cell proliferation assay and Western blot analysis, was conducted to evaluate the prediction results. Results: In the microarray data, 224 differentially expressed genes related to liver fibrosis were considered to be potential targets. Thirty active ingredients of the YGJD and 15 main targets and relevant pathways were identified. Among them, two active ingredients, methylophiopogonone A and 8-geranyloxypsoralen, were validated as exhibiting antifibrotic effects on hepatic stellate cells. Conclusions: We identified the potential active ingredients of the YGJD and proposed the possible explanation for the MOA in the treatment of CHB patients with liver fibrosis. Moreover, this study provides a methodological reference for the systematic investigation of the bioactive compounds and related MOA of a traditional Chinese medicine formula in a clinical context.

6.
Int J Biol Sci ; 15(10): 2211-2223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592236

RESUMO

BACKGROUND: Angiostrongylus cantonensis infection can cause demyelination in the central nervous system, and there is no effective treatment. METHODS: We used dexamethasone, Tanshinone IIA (TSIIA) and Cryptotanshinone(Two traditional Chinese medicine monomers) in combination with albendazole (AB, a standard anti-helminthic compound) to observe their therapeutic effect on demyelination in A. cantonensis-infected mice. Luxol fast blue staining and electron microscope of myelin sheath, Oligodendrocyte (OL) number and myelin basic protein (MBP) expression in brain was detected in above groups. RESULTS: TSIIA+AB facilitated OL proliferation and significantly increased both myelin sheath thickness and the population of small-diameter axons. In addition, TSIIA treatment inhibited the expression of inflammation-related factors (interleukin [IL]-6, IL-1ß, tumor necrosis factor [TNF]-α, inducible nitric oxide synthase [iNOS]) rather than inhibiting eosinophil infiltration in brain. TSIIA also decreased microglial activation and shifted their phenotype from M1 to M2. CONCLUSIONS: Taken together, these results provide evidence that TSIIA combined with AB may be an effective treatment for demyelination caused by A. cantonensis infection and other demyelinating diseases.

7.
Parasit Vectors ; 12(1): 457, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547847

RESUMO

BACKGROUND: Potent granulomatous inflammation responses induced by schistosome eggs and resultant fibrosis are the primary causes of morbidity in schistosomiasis. Recombinant Sj16 (rSj16), a 16-kDa protein of Schistosoma japonicum produced in Escherichia coli, has been demonstrated to have novel immunoregulatory effects in vivo and in vitro. Thus, this study investigated the anti-inflammatory and anti-fibrotic effects of rSj16 treatment in S. japonicum-infected mice and demonstrated the immune modulation between the schistosome and the host. METHODS: Schistosoma japonicum infected mice were treated with the rSj16 protein and Sj16 peptide at different time points post-infection to assess their efficacy at the optimal time point. Sj16 peptide and/or Praziquantel (PZQ) treatments were initiated at week 5 post-infection to compare the therapeutic efficacy of each regimen. Hepatic granulomatous inflammation, fibrosis and cytokine production (pro-inflammatory, Th1, Th2, Th17 and regulatory cytokines IL-10) were detected. Moreover, M2 macrophages were measured to illuminate the mechanisms of Sj16. RESULTS: The rSj16 protein and Sj16 peptide had significant protective effects in S. japonicum-infected mice, as shown by decreased granuloma formation, areas of collagen deposition and inhibition of pro-inflammatory Th1, Th2 and Th17 cytokine production. These protective activities were more obvious when animals were treated with either the Sj16 protein or peptide at early stages post-infection. Interestingly, the combined treatment of PZQ and Sj16 was more effective and upregulated IL-10 production than administration of PZQ alone in infected mice. Furthermore, the Sj16 treatment alleviated the pathological effects associated with activated M2 macrophages. CONCLUSIONS: This study demonstrates the anti-inflammatory and anti-fibrotic effects of rSj16 in schistosomiasis. Therefore, the combination of rSj16 with PZQ could be a viable and promising therapeutic strategy for schistosomiasis. In addition, this investigation provides additional information on schistosome-mediated immune modulation and host-parasite interactions.


Assuntos
Granuloma/prevenção & controle , Proteínas de Helminto/metabolismo , Fatores Imunológicos/metabolismo , Fígado/patologia , Macrófagos/imunologia , Esquistossomose Japônica/patologia , Animais , Anti-Helmínticos/administração & dosagem , Modelos Animais de Doenças , Fibrose/patologia , Fibrose/prevenção & controle , Granuloma/patologia , Proteínas de Helminto/administração & dosagem , Fatores Imunológicos/administração & dosagem , Inflamação/patologia , Inflamação/prevenção & controle , Camundongos , Praziquantel/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/metabolismo , Resultado do Tratamento
8.
Exp Cell Res ; 384(1): 111554, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31415761

RESUMO

BACKGROUND: Angiostrongylus cantonensis (A. cantonensis) is a foodborne parasite that can invade the central nervous system (CNS), resulting in eosinophilic meningitis (EM). However, the mechanism by which A. cantonensis causes eosinophilic infiltration into CNS is not well understood. METHODS: In this study eosinophilic infiltration into the CNS caused by A. cantonensis was assessed based on eosinophil counts and evaluation of interleukin (IL)-5 and -13 levels by real-time PCR in brain of Balb/c mice. The expression and activation of IL-17A, IL17 receptor (IL-17R A), and IL-17RC and the related signaling molecules nuclear factor (NF)-κB1, NF-κB2, NF-κB activator (Act)1, tumor necrosis factor receptor-associated factor (Traf)5, and Traf6 during A. cantonensis infection in brain tissue of Balb/c mice were examined by real-time, western blotting and immunofluroence. A. cantonensis-infected Balb/c mice were treated with IL-17A neutralizing antibody to evaluate the role of IL17A in eosinophil accumulation in the CNS. RESULTS: Our results showed A. cantonensis infection caused eosinophil accumulation and alterations in IL-5 and -13 levels. The expression of IL-17A and -17RA, Act1, and Traf6 but not of IL-17RC and Traf5 was upregulated during infection; this was accompanied by NF-κB1 and -κB2 activation. Importantly, application of IL-17A neutralizing antibody attenuated eosinophil accumulation in CNS and reversed the changes in IL-5 and -13 expression caused by A. cantonensis infection. Additionally, IL-17RA and Traf6 levels decreased, which was accompanied by NF-κB inactivation. CONCLUSION: IL-17A plays an important role in EM caused by A. cantonensis, possibly through activation of NF-κB via the IL-17RA/Traf6 signaling pathway. These findings highlight the potential for using IL-17A neutralizing antibody as a therapeutic strategy for the treatment of EM.

9.
Nature ; 572(7767): 56-61, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31316207

RESUMO

The radiation-based sterile insect technique (SIT) has successfully suppressed field populations of several insect pest species, but its effect on mosquito vector control has been limited. The related incompatible insect technique (IIT)-which uses sterilization caused by the maternally inherited endosymbiotic bacteria Wolbachia-is a promising alternative, but can be undermined by accidental release of females infected with the same Wolbachia strain as the released males. Here we show that combining incompatible and sterile insect techniques (IIT-SIT) enables near elimination of field populations of the world's most invasive mosquito species, Aedes albopictus. Millions of factory-reared adult males with an artificial triple-Wolbachia infection were released, with prior pupal irradiation of the released mosquitoes to prevent unintentionally released triply infected females from successfully reproducing in the field. This successful field trial demonstrates the feasibility of area-wide application of combined IIT-SIT for mosquito vector control.


Assuntos
Aedes/microbiologia , Aedes/fisiologia , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Mosquitos Vetores/fisiologia , Wolbachia/patogenicidade , Aedes/crescimento & desenvolvimento , Animais , China , Copulação , Estudos de Viabilidade , Feminino , Humanos , Mordeduras e Picadas de Insetos/prevenção & controle , Larva/crescimento & desenvolvimento , Larva/microbiologia , Larva/fisiologia , Masculino , Mosquitos Vetores/crescimento & desenvolvimento , Controle de Qualidade , Reprodução
11.
Front Microbiol ; 10: 66, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30766520

RESUMO

Schistosomiasis japonica is a significant health problem that leads to morbidity and mortality of humans. It is characterized by hepatic granulomatous response and fibrosis caused by eggs deposition in the liver. ß-actin, a traditional housekeeping gene, is widely used as an internal control to normalize gene and protein expression. However, ß-actin expression can fluctuate upon the treatment with pharmacological agents or under some physiological and pathological conditions. In this study, we found that the expressions of both ß-actin mRNA and protein increased significantly with hepatic fibrosis formation after 6 weeks infection with Schistosoma japonicum and kept high level during the progression of hepatic fibrosis, while the levels of ß-Tubulin and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) remained stable. The dynamic change of ß-actin was similar with the profibrogenic factors, including α-SMA, Collagen I, and Collagen III. We employed immunofluorescence staining and further showed that the expression level of ß-actin was positively correlated with α-SMA. What is more, there was a positive correlation between the level of ß-actin mRNA and the content of hydroxyproline in liver. This study provides evidences that ß-actin is variable and unsatisfied for application as an internal control in hepatic fibrosis induced by S. japonicum infection.

12.
Biochim Biophys Acta Gene Regul Mech ; 1862(5): 557-566, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30763737

RESUMO

MicroRNA plays a vital role in the regulation of host-parasite interaction. In recent years, genomic and transcriptomic resources have become increasingly available for many helminths, but only a limited number of reports in this area are on the regulatory effects of host microRNAs on parasitic nematodes. In this work, we screened increased expression of host microRNAs after nematode infection from miRNA-seq data and predicted target genes by combined bioinformatics analysis and transcriptional profiling. We elucidated regulatory effects of one host miRNA on nematode infection using miRNA inhibitor and adeno-associated virus (AAV)-based TuD miRNA inhibitor. Using AAV-based TuD miRNA inhibitor, we showed that stable blockade of mmu-miR-101b-3p could alleviate the pathological damages of Angiostrongylus cantonensis, a parasitic nematode. Data from a luciferase report assay showed that mmu-miR-101b-3p targeted the extracellular superoxide dismutase 3 (Acsod3). Increased Acsod3 expression in larvae and alleviated oxidative damages were seen in the groups receiving mmu-miR-101b-3p inhibitor treatment in vitro and AAV-based TuD miRNA inhibitor injection in vivo. Results of this study demonstrate that murine miR-101b-3p inhibits the expression of antioxidant enzyme in A. cantonensis to strengthen host oxidative responses to nematodes. This work expands our knowledge of interspecies regulation of nematode gene expression by of host miRNAs.


Assuntos
Angiostrongylus cantonensis/enzimologia , MicroRNAs/fisiologia , Infecções por Strongylida/genética , Superóxido Dismutase/genética , Angiostrongylus cantonensis/genética , Angiostrongylus cantonensis/crescimento & desenvolvimento , Angiostrongylus cantonensis/ultraestrutura , Animais , Feminino , Larva/enzimologia , Larva/ultraestrutura , Camundongos , MicroRNAs/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Infecções por Strongylida/parasitologia , Superóxido Dismutase/metabolismo
13.
Infect Dis Poverty ; 8(1): 2, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30621776

RESUMO

BACKGROUND: The invasive alien species may lead to great environmental and economic crisis due to its strong capability of occupying the biological niche of native species and altering the ecosystem of the invaded area. However, its potential to serve as the vectors of some specific zoonotic pathogens, especially parasites, has been neglected. Thus, the damage that it may cause has been hugely underestimated in this aspect, which is actually an important public health problem. This paper aims to discuss the current status of zoonotic parasites carried by invasive alien species in China. MAIN BODY: This review summarizes the reported zoonotic parasites carried by invasive alien species in China based on the Database of Invasive Alien Species in China. We summarize their prevalence, threat to human health, related reported cases, and the roles of invasive alien species in the life cycle of these parasites, and the invasion history of some invasive alien species. Furthermore, we sum up the current state of prevention and control of invasive alien species in China, and discuss about the urgency and several feasible strategies for the prevention and control of these zoonoses under the background of booming international communications and inevitable globalization. CONCLUSIONS: Information of the zoonotic parasites carried by invasive alien species neither in China or worldwide, especially related case reports, is limited due to a long-time neglection and lack of monitoring. The underestimation of their damage requires more attention to the monitoring and control and compulsory measures should be taken to control the invasive alien species carrying zoonotic parasites.


Assuntos
Artrópodes/parasitologia , Espécies Introduzidas , Moluscos/parasitologia , Vertebrados/parasitologia , Zoonoses/parasitologia , Distribuição Animal , Animais , China , Interações Hospedeiro-Parasita
14.
Infect Dis Poverty ; 7(1): 78, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30071901

RESUMO

BACKGROUND: The high prevalence of parasitic diseases leads to millions of deaths and disabilities each year in developing countries. China has also been greatly affected by parasitic infections, including filariasis, leishmaniasis, malaria, schistosomiasis, and soil-transmitted nematodosis. However, the situation in China improved dramatically after comprehensive parasitic disease control efforts were strengthened, leading to the elimination of filariasis in 2006 and to significant control over other diseases. However, imported parasitic disease cases are inevitable, and such cases have increasingly been reported as a result of enhanced globalization and international or regional cooperation. These imported diseases represent a major obstacle to the elimination of several parasitoses, such as malaria. MAIN TEXT: This paper reviews imported cases of parasitic diseases in mainland China, particularly malaria and schistosomiasis, based on data reported separately by the Chinese annual reports and from other published papers. We summarize the new challenges that face parasitic disease control efforts in mainland China and perspectives regarding better control. We argue that both the provision of professional education and updated training for medical care personnel and the management and surveillance of people entering China are essential. We recommend that Chinese migrant workers should be considered a priority group for health education and that public awareness of imported diseases should be emphasized. Furthermore, we underscore the importance of investigating the distribution of introduced/potential vectors, parasite susceptibility, and improvements in diagnostic techniques and drug stocks. CONCLUSIONS: Imported cases have become the main challenge to the elimination of several parasitoses, such as malaria and schistosomiasis, in mainland China. China should act to meet these challenges, which are closely associated with national biological safety.


Assuntos
Parasitos/isolamento & purificação , Doenças Parasitárias/epidemiologia , Animais , China/epidemiologia , Humanos , Parasitos/classificação , Parasitos/genética , Parasitos/fisiologia , Doenças Parasitárias/prevenção & controle , Viagem/estatística & dados numéricos
15.
Exp Parasitol ; 191: 82-87, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29981293

RESUMO

Schistosomiasis is a major parasitic disease caused by 3 principal species of schistosome. Studies of schistosome transcriptomes have focused on protein-coding transcripts and although miRNAs are attracting increased attention, few reports have concerned the long noncoding RNAs (lncRNAs). These have been shown to play key roles in the regulation of gene expression through interactions with mRNAs, proteins and miRNAs. In this study, we first identified lncRNAs from RNA-seq data in Schistosoma mansoni and Schistosoma japonicum: 3247 and 3033 potential lncRNAs were found in these two species respectively. ChIP-seq analysis to determine H3K4me3 profiles along the gene regions corresponding to lncRNAs showed that in 12% of cases this mark was enriched in regions proximal to the transcription start sites, supporting their validity as actively transcribed genes. Besides, the sequence conservation of lncRNAs between schistosome species was much lower than that of mRNAs, but higher than that of the randomly selected genomic sequences, which is consistent with that in mammals. Our results demonstrate that lncRNAs form a significant part of the schistosome transcriptome and suggest that they play an important role in the biology of the parasite.


Assuntos
RNA Longo não Codificante/isolamento & purificação , Schistosoma japonicum/genética , Schistosoma mansoni/genética , Animais , Sequência de Bases , Sequência Conservada , Feminino , Histonas/metabolismo , Masculino , Regiões Promotoras Genéticas , RNA de Helmintos/química , Schistosoma haematobium/genética , Esquistossomose/diagnóstico , Esquistossomose/parasitologia , Esquistossomose/prevenção & controle , Alinhamento de Sequência , Transcriptoma/genética
16.
Mediators Inflamm ; 2018: 9098287, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29855635

RESUMO

[This corrects the article DOI: 10.1155/2017/3513651.].

17.
PLoS Negl Trop Dis ; 12(5): e0006548, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29813073

RESUMO

BACKGROUND: Schistosomiasis is a snail-borne parasitic disease and is endemic in many tropical and subtropical countries. Biomphalaria straminea, an intermediate host for Schistosoma mansoni, is native to the southeastern part of South America and has established in other regions of South America, Central America and southern China during the last decades. S. mansoni is endemic in Africa, the Middle East, South America and the Caribbean. Knowledge of the potential global distribution of this snail is essential for risk assessment, monitoring, disease prevention and control. METHODS AND FINDINGS: A comprehensive database of cross-continental occurrence for B. straminea was compiled to construct ecological models. We used several approaches to investigate the distribution of B. straminea, including direct comparison of climatic conditions, principal component analysis and niche overlap analyses to detect niche shifts. We also investigated the impacts of bioclimatic and human factors, and then used the bioclimatic and footprint layers to predict the potential distribution of B. straminea at global scale. We detected niche shifts accompanying the invasions of B. straminea in the Americas and China. The introduced populations had enlarged its habitats to subtropical regions where annual mean temperature is relatively low. Annual mean temperature, isothermality and temperature seasonality were identified as most important climatic features for the occurrence of B. straminea. Additionally, human factors improved the model prediction (P<0.001). Our model showed that under current climate conditions the snail should mostly be confined to the tropic and subtropic regions, including South America, Central America, Sub-Saharan Africa and Southeast Asia. CONCLUSIONS: Our results confirmed that niche shifts took place in the invasions of B. straminea, in which bioclimatic and human factors played an important role. Our model predicted the global distribution of B. straminea based on habitat suitability, which would help for prioritizing monitoring and management efforts for B. straminea control in the context of ongoing climate change and human disturbances.


Assuntos
Schistosoma mansoni/fisiologia , Esquistossomose mansoni/parasitologia , África/epidemiologia , Animais , Ásia/epidemiologia , Biomphalaria/parasitologia , Vetores de Doenças , Humanos , Schistosoma mansoni/genética , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/transmissão , América do Sul/epidemiologia
18.
Trends Parasitol ; 34(6): 493-510, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29627269

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal) This article has been retracted at the request of the authors: Benjamin Sanogo, Dongjuan Yuan, Xin Zeng, Yanhua Zhang, and Zhongdao Wu. Our article reviews the evolution, geography, diversity, genetics and host-compatibility of human schistosomes and their hosts. It has come to our attention that readers have found some of the content in the article to be confusing or misleading. As authors, we have tried our best to share our scientific discovery and understanding faithfully, but we also agree that scientific reports should stand up to doubt and discussion. After serious consideration, to avoid confusion in the Schistosoma research community, we are retracting the Review. We apologize to the community for any inconvenience we have caused.

19.
Infect Dis Poverty ; 7(1): 28, 2018 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-29628017

RESUMO

BACKGROUND: Snail-borne parasitic diseases, such as angiostrongyliasis, clonorchiasis, fascioliasis, fasciolopsiasis, opisthorchiasis, paragonimiasis and schistosomiasis, pose risks to human health and cause major socioeconomic problems in many tropical and sub-tropical countries. In this review we summarize the core roles of snails in the life cycles of the parasites they host, their clinical manifestations and disease distributions, as well as snail control methods. MAIN BODY: Snails have four roles in the life cycles of the parasites they host: as an intermediate host infected by the first-stage larvae, as the only intermediate host infected by miracidia, as the first intermediate host that ingests the parasite eggs are ingested, and as the first intermediate host penetrated by miracidia with or without the second intermediate host being an aquatic animal. Snail-borne parasitic diseases target many organs, such as the lungs, liver, biliary tract, intestines, brain and kidneys, leading to overactive immune responses, cancers, organ failure, infertility and even death. Developing countries in Africa, Asia and Latin America have the highest incidences of these diseases, while some endemic parasites have developed into worldwide epidemics through the global spread of snails. Physical, chemical and biological methods have been introduced to control the host snail populations to prevent disease. CONCLUSIONS: In this review, we summarize the roles of snails in the life cycles of the parasites they host, the worldwide distribution of parasite-transmitting snails, the epidemiology and pathogenesis of snail-transmitted parasitic diseases, and the existing snail control measures, which will contribute to further understanding the snail-parasite relationship and new strategies for controlling snail-borne parasitic diseases.


Assuntos
Vetores de Doenças , Interações Hospedeiro-Parasita , Doenças Parasitárias , Caramujos/parasitologia , Animais , Humanos , Doenças Parasitárias/epidemiologia , Doenças Parasitárias/prevenção & controle , Doenças Parasitárias/transmissão
20.
Parasit Vectors ; 11(1): 189, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29554945

RESUMO

BACKGROUND: Mass egg production is an important component of Aedes albopictus mosquito control programs, such as the sterile insect technique and incompatible insect technique, which requires the releases of large number of sterile males. Developing standard operating procedures and optimized cages for adult maintenance of Ae. albopictus can improve the mass rearing efficiency. METHODS: Three different sex ratios of females to males with a total number of 4,000 mosquitoes were tested by evaluating the insemination rate, egg production (total number of eggs per cage), female fecundity and egg hatch rate in small cage (30 × 30 × 30 cm). Blood meals with adenosine triphosphate (ATP, 0.05 g/ml), cage structures (Big cage A: 90 × 30 × 30 cm; Big cage B: 90 × 30 × 50 cm or 90 × 50 × 30 cm) and rearing densities (12,000, 16,000 and 20,000 mosquitoes, corresponding to 0.9 cm2/mosquito, 0.675 cm2/mosquito and 0.54 cm2/mosquito, respectively) were also tested and evaluated on the basis of egg production, female fecundity and egg hatch rate. An adult rearing unit holding 15 of Big cage A with optimal egg production was designed to produce 10 million eggs per rearing cycle in a 1.8 m2 space. RESULTS: Female to male ratios at 3:1 in small cages resulted in higher egg production but did not affect insemination rate, female fecundity and egg hatch rate. A concentration of 0.05 g/ml of ATP added to blood meals improved the blood-feeding frequency and thus increased the overall egg production per cage. Cage structures affected the egg production per cage, but not egg hatch rate. A medium rearing density at 0.675 cm2/mosquito (16,000 mosquitoes) resulted in higher egg production compared to both low and high densities. An adult rearing unit for Ae. albopictus on the basis of Big cage A has been developed with the capacity of producing 10 million eggs within 15 days. CONCLUSIONS: Our results have indicated that the adult rearing methods and adult maintenance unit are recommended for Ae. albopictus mass rearing in support of the establishment of a medium-sized mosquito factory.


Assuntos
Aedes/fisiologia , Controle de Mosquitos/métodos , Aedes/crescimento & desenvolvimento , Animais , Feminino , Fertilidade , Masculino , Controle de Mosquitos/instrumentação , Óvulo/crescimento & desenvolvimento , Reprodução
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