Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
Microorganisms ; 12(3)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38543573

RESUMO

Glugea plecoglossi is an obligate intracellular microsporidium, which poses a significant threat to ayu (Plecoglossus altivelis). In vitro cultivation models are invaluable tools for investigating intracellular microorganisms, including G. plecoglossil. In this study, we attempted to in vitro cultivate G. plecoglossi using primary cultures derived from ayu monocytes/macrophages (MO/MΦ), a murine-derived macrophage cell line RAW264.7, and the epithelioma papulosum cyprini (EPC) cell line. The results demonstrated that MO/MΦ infected with spores exhibited a pronounced immune response which was presented by rapidly high expression levels of inflammatory cytokines, such as PaIL-1ß, PaTNF-α, PaIL-10, and PaTGF-ß, and detached within 96 h post-infection (hpi). Infected RAW264.7 cells remained capable of stable passage yet exhibited cellular deformation with a decrease in intracellular spores occurring around 8 days post-infection (dpi). In contrast, EPC cells promised a substantial parasite population, and the cytokine expression levels returned to normal by 8 dpi. In addition, G. plecoglossi spores recovered from EPC cells could infect young ayu, suggesting that EPC cells might be used as an in vitro cultivation system for G. plecoglossi.

2.
Fish Shellfish Immunol ; 145: 109364, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199264

RESUMO

Micropterus salmoides rhabdovirus (MSRV) is one of the main pathogens of largemouth bass, leading to serious economic losses. The G protein, as the only envelope protein present on the surface of MSRV virion, contains immune-related antigenic determinants, thereby becoming the primary target for the design of MSRV vaccines. Here, we displayed the G protein on the surface of yeast cells (named EBY100/pYD1-G) and conducted a preliminary assessment of the protective efficacy of the recombinant yeast vaccine. Upon oral vaccination, a robust immune response was observed in systemic and mucosal tissue. Remarkably, following the MSRV challenge, the relative percent survival of EBY100/pYD1-G treated largemouth bass significantly increased to 66.7 %. In addition, oral administration inhibited viral replication and alleviated the pathological symptoms of MSRV-infected largemouth bass. These results suggest that EBY100/pYD1-G could be used as a potential oral vaccine against MSRV infection.


Assuntos
Bass , Doenças dos Peixes , Rhabdoviridae , Animais , Saccharomyces cerevisiae , Vacinação , Proteínas Fúngicas , Vacinas Sintéticas
3.
Front Microbiol ; 14: 1238376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822745

RESUMO

Zoonotic parasites pose significant health risks globally. In the present study, we combined a microfluidic chip with loop-mediated isothermal amplification (on-chip LAMP) to detect five zoonotic parasites: Toxoplasma gondii, Cryptosporidium parvum, Cryptosporidium hominis, Clonorchis sinensis, and Taenia solium. This method enabled the simultaneous parallel analysis of five genetic markers from a maximum of four samples per chip. The on-chip LAMP assay was conducted in a highly automated format via the addition (by pipetting) of each sample in a single operation. The reaction was performed in volumes as low as 5 µL at a temperature of 65°C for 60 min, achieving limits of detection ranging from 10-2 to 10-3 pg./µL of recombinant plasmid DNA. All the time-to-positive values were less than 40 min, and almost all the coefficients of variation were less than 10%, even when using limit of detection concentrations for multiple pathogens, indicating robust reproducibility among replicates. The clinical sensitivity and specificity for detecting 135 field samples were 98.08 and 97.59%, respectively, compared with traditional biological methods, indicating good applicability in the detection of field samples. This on-chip LAMP assay allows for low reagent consumption, ease of operation, and multiple analyses of samples and genetic targets, and is applicable for on-site detection and the routine monitoring of multiple zoonotic parasites.

4.
Heliyon ; 9(8): e18641, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560661

RESUMO

Based on the simulation of the fluid-structure interaction response, the cause of an overturning of a gantry crane induced by a downburst in Shenzhen is studied in this paper. According to the results, (1) Vicroy's downburst model could establish the steady-state wind field of the downburst more reasonably when there was only low-level wind speed observation data, and its simulation results were close to the two-dimensional downburst numerical simulation results; (2) Compared with the normal exponential vertical profile of wind speed, the disturbance caused by the front girder of the double-girder gantry crane structure under the downburst wind field was more severe, which increases the probability of the gantry crane overturning. (3) The downwind displacement of the main girder of the gantry crane under the condition of downburst is far greater than that under the normal condition. At the same time, under the condition of downburst, the pressure difference on the surface of the gantry crane was greater, and the distribution of the support reaction force was more uneven, resulting in a stronger overturning tendency of the gantry crane. (4) Under the condition of downburst, the overturning moment and the shearing force borne by the foundation of gantry crane exceeded the critical value to maintain the stability of the gantry crane by the gravity, resulting in the overturning of the gantry crane.

5.
Microbiol Spectr ; 10(4): e0201522, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35950758

RESUMO

Widely distributed multidrug-resistant (MDR) bacteria threaten animals and human health. Nevertheless, few antimicrobial resistance (AMR) surveys of large-scale animal-derived bacteria have been explored. Here, 1,468 (97.54%) Escherichia coli strains were isolated from 1,505 pig (1,060) and chicken (445) anal swab samples from 11 cities in Zhejiang Province, China, in 2020. These isolates had a high resistance to tetracycline (92.92%), sulfisoxazole (93.05%), florfenicol (83.11%), and ampicillin (78.27%). More than 88.68% of the strains were MDR bacteria. A low AMR ratio to the "last-resort" antimicrobials tigecycline (0.75%), colistin (1.36%), and meropenem (0.75%) were found. The AMR of E. coli from pigs was higher than that of chickens. Eighteen strains among 31 MDR strains that were resistant to "last-resort" antimicrobials could transfer the AMR genes (mcr-1, tet(X), and blaNDM) to the recipient strain J53, which confer colistin, tigecycline, and carbapenem resistance, respectively. The homology among mcr-1-carrying isolates was relatively high, and the sequence types were mainly ST5529, ST101, and ST354, while the homology of isolates harboring tet(X4) and blaNDM-5 genes were different. The mcr-1, blaNDM-5, and tet(X4) genes in strains LS45, JH51, and TZ118 were identified on the Incl2, IncHI2, and IncX1 plasmids, respectively. Moreover, tet(A), sul2, floR, and blaTEM-1B were the most common ARGs in 31 strains. Additionally, the heavy metals copper and zinc had a significant correlation with amoxicillin/clavulanate and tetracycline resistance. Controlling the movement of animals between cities and reducing the use of antimicrobials are effective methods to reduce the threat of AMR bacteria. IMPORTANCE Pigs and chickens are the most common food animals that are the important vectors for spreading antimicrobial-resistant pathogens among animals and humans. Limited systematic AMR monitoring of these food animal origin bacteria had been reported, especially in developed areas of China. Our study provides a comprehensive and systematic study of AMR in Escherichia coli from eastern China. The AMR of E. coli strains among the animals or cities has statistically significant differences. Moreover, the mcr-1, tet(X4), and blaNDM-5 genes, considered resistant to the last line of AMR, were identified in part of farms. The transferability and the prevalence of these AMR strains were intensively studied. Our monitoring is comparable to human clinical research and has an essential reference for public health safety. These findings will provide early warning for AMR strains and guide the clinical use of antibiotics to control the spread of antibiotic resistance.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Antibacterianos/farmacologia , Galinhas , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Suínos , Tigeciclina/farmacologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-35682078

RESUMO

Using surface air temperature observations from 1901 to 2020, this study compared the warming trends of Shanghai and Hong Kong over a period of 120 years. The statistical results reveal the following: (1) The average temperatures of the two cities underwent fluctuating increases during the past 120 years, with linear warming rates of 0.23 °C/decade in Shanghai and 0.13 °C/decade in Hong Kong. (2) The fluctuation ranges of maximum temperature in the two cities were considerably higher than those of mean temperature. Moreover, in both cities, the annual mean maximum temperature decreased during a phase of more than a decade. The fluctuation ranges of minimum temperature were smaller, whereas the linear increases were higher than those for the mean temperature. (3) The diurnal temperature ranges (DTRs) of the two cities decreased; a certain phase of the decreases in DTR in the two cities was caused by decreases in the maximum temperature. (4) At a certain stage of urban development, owing to the shading effect of new high-rise buildings, the solar shortwave radiation reaching the Earth's surface decreased, and anthropogenic heat generated by the energy consumption of buildings and urban human activities at that time was not sufficient to make up for the reduced shortwave radiation. This result may have led to the declines in the maximum temperature experienced by both cities. (5) Currently, the number of hot days and extremely hot days in the two cities has increased significantly compared with that a century ago, indicating that climate warming has an adverse impact on human settlements.


Assuntos
Temperatura Alta , China , Cidades , Hong Kong , Humanos , Temperatura
7.
Microbiol Resour Announc ; 11(7): e0007322, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35639030

RESUMO

Here, we report the complete genome sequence of Vibrio harveyi strain ATCC 33866, generated from Illumina and Oxford Nanopore sequencing. The assembled genome sequence comprises two circular chromosomes with lengths of 3,504,760 bp and 2,218,060 bp, respectively.

8.
Eur J Med Chem ; 226: 113855, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34555614

RESUMO

Lysine-specific demethylase 5A (KDM5A, also named RBP2 or JARID1A) is a demethylase that can remove methyl groups from histones H3K4me1/2/3. It is aberrantly expressed in many cancers, where it impedes differentiation and contributes to cancer cell proliferation, cell metastasis and invasiveness, drug resistance, and is associated with poor prognosis. Pharmacological inhibition of KDM5A has been reported to significantly attenuate tumor progression in vitro and in vivo in a range of solid tumors and acute myeloid leukemia. This review will present the structural aspects of KDM5A, its role in carcinogenesis, a comparison of currently available approaches for screening KDM5A inhibitors, a classification of KDM5A inhibitors, and its potential as a drug target in cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias/tratamento farmacológico , Proteína 2 de Ligação ao Retinoblastoma/antagonistas & inibidores , Antineoplásicos/química , Inibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Neoplasias/metabolismo , Proteína 2 de Ligação ao Retinoblastoma/química , Proteína 2 de Ligação ao Retinoblastoma/metabolismo
9.
Anal Methods ; 13(24): 2710-2721, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34041513

RESUMO

Waterborne pathogens are becoming a serious worldwide health hazard; thus, the regular monitoring of epidemic pathogens is urgently required for public safety. In the present study, we developed a microfluidic chip integrated loop-mediated isothermal amplification technique (on-chip LAMP) to simultaneously detect 10 waterborne pathogenic bacteria, Campylobacter jejuni, Listeria monocytogenes, Salmonella enterica, Shigella flexneri, Staphylococcus aureus, Vibrio alginolyticus, V. cholerae, V. parahemolyticus, V. vulnificus, and Yersinia enterocolitica. This method was capable of simultaneously completing 22 genetic analyses of two specimens and achieved limits of detection ranging from 7.92 × 10-3 to 9.54 × 10-1 pg of genomic DNA of pure bacteria per reaction. The processes from sample loading to microfluidic operation were in a highly automated format, and the LAMP reaction ran to completion within 35 minutes, with a minimal volume of 22 µl per each half of a single chip. The coefficient of variation for the time-to-positive value was less than 0.1, indicating an excellent reproducibility of the dual-sample on-chip LAMP assay. The clinical sensitivity and specificity in analyses of coastal water samples were 93.1% and 98.0%, respectively, in comparison with traditional microbiological methods. Our established dual-sample on-chip LAMP assay provides an effective multiple-pathogen analysis of waterborne bacterial pathogens. This indicates that the method is applicable for on-site detection and routine monitoring of waterborne bacteria in aquatic environments.


Assuntos
Listeria monocytogenes , Microfluídica , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Reprodutibilidade dos Testes
10.
J Fish Dis ; 44(4): 401-413, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33340375

RESUMO

Rapid and user-friendly diagnostic tests are necessary for early diagnosis and immediate detection of diseases, particularly for on-site screening of pathogenic microorganisms in aquaculture. In this study, we developed a dual-sample microfluidic chip integrated with a real-time fluorogenic loop-mediated isothermal amplification assay (dual-sample on-chip LAMP) to simultaneously detect 10 pathogenic microorganisms, that is Aeromonas hydrophila, Edwardsiella tarda, Vibrio harveyi, V. alginolyticus, V. anguillarum, V. parahaemolyticus, V. vulnificus, infectious hypodermal and haematopoietic necrosis virus, infectious spleen and kidney necrosis virus, and white spot syndrome virus. This on-chip LAMP provided a nearly automated protocol that can analyse two samples simultaneously, and the tests achieved limits of detection (LOD) ranging from 100 to 10-1  pg/µl for genomic DNA of tested bacteria and 10-4 to 10-5  pg/µl for recombinant plasmid DNA of tested viruses, with run times averaging less than 30 min. The coefficient of variation for the time-to-positive value was less than 10%, reflecting a robust reproducibility. The clinical sensitivity and specificity were 93.52% and 85.53%, respectively, compared to conventional microbiological or clinical methods. The on-chip LAMP assay provides an effective dual-sample and multiple pathogen analysis, and thus would be applicable to on-site detection and routine monitoring of multiple pathogens in aquaculture.


Assuntos
Aeromonas hydrophila/isolamento & purificação , Densovirinae/isolamento & purificação , Edwardsiella tarda/isolamento & purificação , Iridoviridae/isolamento & purificação , Microfluídica/métodos , Técnicas de Diagnóstico Molecular/veterinária , Técnicas de Amplificação de Ácido Nucleico/veterinária , Vibrio/isolamento & purificação , Vírus da Síndrome da Mancha Branca 1/isolamento & purificação , Animais , Crustáceos/microbiologia , Crustáceos/virologia , Infecções por Vírus de DNA/diagnóstico , Infecções por Vírus de DNA/veterinária , Infecções por Vírus de DNA/virologia , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/microbiologia , Doenças dos Peixes/virologia , Peixes/microbiologia , Peixes/virologia , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Limite de Detecção , Técnicas de Diagnóstico Molecular/métodos , Moluscos/microbiologia , Moluscos/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Indian J Microbiol ; 60(2): 214-221, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32255854

RESUMO

A 20-day trial was conducted to reveal bacterial community dynamics in a commercial nursery of larval Litopenaeus vannamei larvae. The bacterial communities in the ambient water were profiled by high-throughput sequencing of the V4-V5 hypervariable region of the 16S rRNA gene. The results indicated that the dominant bacterial phyla between the metamorphosis stage and postlarval stage were Bacteroidetes, Proteobacteria, Cyanobacteria, and Firmicutes, representing more than 80.09% of the bacterial operational taxonomic units. The relative abundance among bacterial phyla notably differed between the two stages. The relative abundance of Cyanobacteria was higher in the metamorphosis stage, while that of Bacteroidetes was higher and more stable in the postlarval stage. At the class level, the relative abundance of Sphingobacteriia and Alphaproteobacteria increased markedly in the postlarval stage, while that of Flavobacteriia decreased. Redundancy analysis showed that bacterial composition in the metamorphosis stage was positively correlated with salinity, alkalinity, and pH, while in the postlarval stage, it was positively correlated with ammonium nitrogen and nitrite nitrogen. Thus, microbial community diversity in the nursery phase varies per rearing stage.

12.
Zool Res ; 41(2): 123-137, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32150792

RESUMO

Interleukin-34 (IL-34) is a novel cytokine that plays an important role in innate immunity and inflammatory processes by binding to the colony-stimulating factor-1 receptor (CSF-1R). However, information on the function of IL-34 in fish remains limited. In the present study, we identified an IL-34 homolog from mudskippers ( Boleophthalmus pectinirostris). In silico analysis showed that the mudskipper IL-34 (BpIL-34) was similar to other known IL-34 variants in sequence and structure and was most closely related to an orange-spotted grouper ( Epinephelus coioides) homolog. BpIL-34 transcripts were constitutively expressed in various tissues, with the highest level of expression found in the brain. Edwardsiella tarda infection significantly up-regulated the mRNA expression of BpIL-34 in the mudskipper tissues. The recombinant mature BpIL-34 peptide (rBpIL-34) was purified and used to produce anti-rBpIL-34 IgG. Western blot analysis combined with PNGase F digestion revealed that native BpIL-34 in monocytes/macrophages (MOs/MФs) was N-glycosylated. In vitro, rBpIL-34 treatment enhanced the phagocytotic and bactericidal activity of mudskipper MOs/MФs, as well as the mRNA expression of pro-inflammatory cytokines like tumor necrosis factor α ( BpTNF-α) and BpIL-1ß in these cells. Furthermore, the knockdown of mudskipper CSF-1R1 ( BpCSF-1R1), but not mudskipper BpCSF-1R2, significantly inhibited the rBpIL-34-mediated enhanced effect on MO/MФ function. In conclusion, our results indicate that mudskipper BpIL-34 modulates the functions of MOs/MФs via BpCSF-1R1.


Assuntos
Edwardsiella tarda/fisiologia , Proteínas de Peixes/genética , Peixes/genética , Interleucinas/genética , Fator Estimulador de Colônias de Macrófagos/genética , Macrófagos/imunologia , Monócitos/imunologia , Animais , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/veterinária , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Peixes/imunologia , Imunidade Inata , Interleucinas/imunologia , Fator Estimulador de Colônias de Macrófagos/imunologia
13.
Dev Comp Immunol ; 103: 103511, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31580833

RESUMO

ß-defensin is a cationic host defense peptide actively participating in host innate immune response against pathogens. In teleost fish, ß-defensin exhibits a diversity in genotypes and functions. Herein, a ß-defensin homolog (PaBD) was identified from ayu, Plecoglossus altivelis, showing multiple tissues' upregulation against Vibrio anguillarum challenge. In vivo experiments revealed that intraperitoneal injection of chemically synthesized mature PaBD (mPaBD) increased the survival rate of V. anguillarum-infected ayu, accompanied by reduced bacterial load and decreased tissue mRNA levels of tumor necrosis factor α (PaTNF-α) and interleukin 1ß (PaIL-1ß). However, in vitro, mPaBD showed weak bactericidal activity against V. anguillarum. Interestingly, mPaBD enhanced phagocytosis, intracellular bacterial killing, and respiratory burst of ayu monocytes/macrophages (MO/MΦ). Moreover, it inhibited mRNA levels of PaIL-1ß and PaTNF-α in MO/MФ upon V. anguillarum infection. In conclusion, PaBD protects ayu against V. anguillarum challenge not only through its direct antibacterial ability, but also through its immunomodulation in MO/MΦ.


Assuntos
Doenças dos Peixes/imunologia , Proteínas de Peixes/metabolismo , Osmeriformes/imunologia , Vibrioses/veterinária , Vibrio/fisiologia , beta-Defensinas/metabolismo , Sequência de Aminoácidos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Carga Bacteriana/efeitos dos fármacos , Citocinas/genética , Doenças dos Peixes/microbiologia , Doenças dos Peixes/prevenção & controle , Proteínas de Peixes/administração & dosagem , Proteínas de Peixes/genética , Imunomodulação , Macrófagos/imunologia , Macrófagos/microbiologia , Monócitos/imunologia , Monócitos/microbiologia , Osmeriformes/classificação , Osmeriformes/genética , Fagocitose , Filogenia , Explosão Respiratória , Alinhamento de Sequência , Taxa de Sobrevida , Distribuição Tecidual , Vibrio/efeitos dos fármacos , Vibrioses/imunologia , Vibrioses/microbiologia , Vibrioses/prevenção & controle , beta-Defensinas/administração & dosagem , beta-Defensinas/genética
14.
Front Microbiol ; 8: 2176, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29167662

RESUMO

Haemonchus contortus (H. contortus) is one of the most important parasites of small ruminants, especially goats and sheep. The complex life cycle of this nematode is a main obstacle for the control and prevention of haemonchosis. So far, a special form of arrested development called diapause different from the dauer stage in Caenorhabditis elegans (C. elegans) has been found in many parasitic nematodes. In our previous study, we have characterized a novel gene Hc-daf-22 from H. contortus sharing high homology with Ce-daf-22 and functional analysis showed this gene has similar biological function with Ce-daf-22. In this study, Hc-daf-22 mutants were constructed using site-directed mutagenesis, and carried out rescue experiments, RNA interference (RNAi) experiments and in vitro enzyme activity analysis with the mutants to further explore the precise function site of Hc-DAF-22. The results showed that Hc-daf-22 mutants could be expressed in the rescued ok693 worms and the expression positions were mainly in the intestine which was identical with that of Hc-daf-22 rescued worms. Through lipid staining we found that Hc-daf-22 could rescue daf-22 mutant (ok693) from the fatty acid metabolism deficiency while Hc-daf-22 mutants failed. Brood size and body length analyses in rescue experiment along with body length and life span analyses in RNAi experiment elucidated that Hc-daf-22 resembled Ce-daf-22 in effecting the development and capacity of C. elegans and mutants impaired the function of Hc-daf-22. Together with the protease activity assay, this research revealed three important active resides 84C/299H/349H in Hc-DAF-22 by site-directed mutagenesis.

15.
Fish Shellfish Immunol ; 68: 479-487, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28756287

RESUMO

Gut microbiota plays fundamental roles in protection against pathogen invasion. However, the mechanism and extent of responses of gut microbiota to pathogenic infection are poorly understood. This study investigated the gut bacterial communities and immune responses of ayu (Plecoglossus altivelis) upon exposure to Vibrio anguillarum. The succession of V. anguillarum infection was evidenced by increased expression of immune genes and bacterial loads in ayu tissues, which in turn altered the composition and predicted functions of gut bacterial community. The dynamics of gut bacterial diversity and evenness were temporally stable in control ayu but were reduced in infected subjects, particularly at the late stages of infection. Variations in the gut microbiota were significantly associated with the expression levels of TNF-α (P = 0.019) and IL-1 ß (P = 0.013). The profiles of certain gut bacterial taxa were indicative of V. anguillarum infection. Compared with healthy controls, the ayu infected with V. anguillarum possessed less complex, fewer connected, and lower cooperative gut bacterial interspecies interaction, coinciding with significant shifts in keystone species. These findings imply that V. anguillarum infection substantially disrupted the compositions and interspecies interaction of ayu gut bacterial community, thereby altering gut microbial-mediated functions and inducing host immune responses. This study provides an integrated overview on the interaction between the gut microbiota and host immune responses to pathogen infection from an ecological perspective.


Assuntos
Doenças dos Peixes/imunologia , Microbioma Gastrointestinal , Imunidade Inata , Osmeriformes , Vibrioses/veterinária , Animais , Doenças dos Peixes/microbiologia , Distribuição Aleatória , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/microbiologia
16.
Parasit Vectors ; 10(1): 67, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28166831

RESUMO

BACKGROUND: Enoyl-CoA hydratase (MAOC) is required for the biosynthesis of the fatty acid-derive side chains of the ascaroside via peroxisome ß-oxidation in the free-living nematode Caenorhabditis elegans. The derivative of dideoxy-sugar, ascarylose is used as dauer pheromones or daumones to induce development of the stress-resistant dauer larvae stage. METHODS: Hc-maoc-1 gene was obtained by searching the Wellcome Trusts Sanger Institute's H. contortus genomic database. qRT-PCR was performed to analyse the transcriptional levels of Hc-maoc-1 with different developmental stages as templates. IFA was carried out to determine the expression pattern in L3 larvae and micro-injection was used to verify the promoter activity of 5'-flanking region of Hc-maoc-1. Overexpression and RNAi experiments were applied in N2 strain to ascertain the gene function of Hc-maoc-1. RESULTS: The full-length cDNA of Hc-maoc-1 was 900 bp in length, which contained eight exons separated by seven introns and possessed the Hotdog domain and the MaoC-like domain, together with several other residues and a hydratase 2 motif. It was transcribed throughout the lifecycle and peaked in the fourth-stage larvae (L4) of H. contortus; however, its transcription level decreased in diapausing L4. The protein expression and location of Hc-MAOC-1 were mainly in the intestine of L3 larvae. Overexpression of Ce-maoc-1 and Hc-maoc-1 in C. elegans showed extended lifespan and increased body size. The protein Ce-MAOC-1 and Hc-MAOC-1 were localized in the intestine with a punctate pattern. In C. elegans, knockdown of Ce-maoc-1 conferred shortened lifespan and body lengths, decreased brood size and increased lipid storage. CONCLUSION: Caenorhabditis elegans was used as a model organism to ascertain the function of Hc-maoc-1 in H. contortus. Our results showed the similar characteristics and functions with Ce-maoc-1 and provided evidences of the potential functions of Hc-maoc-1 in biosynthesis of daumones in H. contortus.


Assuntos
Enoil-CoA Hidratase/genética , Enoil-CoA Hidratase/metabolismo , Haemonchus/enzimologia , Haemonchus/crescimento & desenvolvimento , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Técnica Direta de Fluorescência para Anticorpo , Perfilação da Expressão Gênica , Haemonchus/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
17.
Parasit Vectors ; 9(1): 422, 2016 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-27472920

RESUMO

BACKGROUND: The strongylid nematode Haemonchus contortus is a parasite of major concern for modern livestock husbandry because hostile environmental conditions may induce diapause in the early fourth-stage larvae. METHODS: A new gene Hc-daf-22 was identified which is the homologue of Ce-daf-22 and human SCPx. Genome walking and RACE were performed to obtain the whole cDNA and genomic sequence of this gene. Using qRT-PCR with all developmental stages as templates to explore the transcription level and micro-injection was applied to confirm the promoter activity of the 5'-flanking region. Overexpression, rescue and RNA interference experiments were performed in N2, daf-22 mutant (ok 693) strains of C. elegans to study the gene function of Hc-daf-22. RESULTS: The full length gene of Hc-daf-22 (6,939 bp) contained 16 exons separated by 15 introns, and encoded a cDNA of 1,602 bp (533 amino acids, estimated at about 59.3 kDa) with a peak in L3 and L4 in transcriptional level. The Hc-DAF-22 protein was consisted of a 3-oxoacyl-CoA thiolase domain and a SCP2 domain and evolutionarily conserved. The 1,548 bp fragment upstream of the 5'-flanking region was confirmed to have promoter activity compared with 5'-flanking region of Ce-daf-22. The rescue experiment by micro-injection of daf-22 (ok693) mutant strain showed significant increase in body size and brood size in the rescued worms with significantly reduced or completely absent fat granules confirmed by Oil red O staining, indicating that Hc-daf-22 could partially rescue the function of Ce-daf-22. Furthermore, RNAi with Hc-daf-22 could partially silence the endogenous Ce-daf-22 in N2 worms and mimic the phenotype of daf-22 (ok693) mutants. CONCLUSION: The gene Hc-daf-22 was isolated and its function identified using C. elegans as a model organism. Our results indicate that Hc-daf-22 shared similar characteristics and function with Ce-daf-22 and may play an important role in peroxisomal ß-oxidation and the development in H. contortus.


Assuntos
Hemoncose/veterinária , Haemonchus/metabolismo , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Doenças dos Ovinos/parasitologia , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/parasitologia , DNA Complementar/genética , DNA Complementar/metabolismo , Hemoncose/parasitologia , Haemonchus/química , Haemonchus/genética , Proteínas de Helminto/química , Dados de Sequência Molecular , Alinhamento de Sequência , Ovinos
18.
Parasit Vectors ; 8: 235, 2015 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-25903558

RESUMO

BACKGROUND: Haemonchus contortus is a common bloodsucking nematode causing widespread economic loss in agriculture. Upon H. contortus infection, a series of host responses is elicited, especially those related to T lymphocyte immunity. Existing studies mainly focus on the general immune responses of sheep T lymphocyte to H. contortus, lacking investigations at the molecular level. The objective of this study was to obtain a systematic transcriptional profiling of the T lymphocytes in H. contortus primary-infected sheep. METHODS: Nematode-free sheep were orally infected once with H. contortus L3s. T lymphocyte samples were collected from the peripheral blood of 0, 3, 30 and 60 days post infection (dpi) infected sheep. Microarrays were used to compare gene transcription levels between samples. Quantitative RT-PCR was employed to validate the microarray data. Gene Ontology and KEGG pathway analysis were utilized for the annotation of differentially expressed genes. RESULTS: Our microarray data was consistent with qPCR results. From microarrays, 853, 242 and 42 differentially expressed genes were obtained in the 3d vs. 0d, 30d vs. 0d and 60d vs. 0d comparison groups, respectively. Gene Ontology and KEGG pathway analysis indicated that these genes were involved in metabolism, signaling, cell growth and immune system processes. Functional analysis of significant differentially expressed genes, such as SLC9A3R2, ABCB9, COMMD4, SUGT1, FCER1G, GSK3A, PAK4 and FCER2, revealed a crucial association with cellular homeostasis maintenance and immune response. Our data suggested that maintaining both effective immunological response and natural cellular activity are important for T lymphocytes in fighting against H. contortus infection. CONCLUSIONS: Our results provide a substantial list of candidate genes in sheep T lymphocytes response to H. contortus infection, and contribute novel insights into a general immune response upon infection.


Assuntos
Regulação da Expressão Gênica/imunologia , Hemoncose/veterinária , Haemonchus/fisiologia , Doenças dos Ovinos/parasitologia , Linfócitos T/fisiologia , Transcriptoma , Animais , Hemoncose/imunologia , Hemoncose/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos , Doenças dos Ovinos/imunologia
19.
Exp Parasitol ; 145: 87-98, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25128369

RESUMO

Aminopeptidase H11 present in the surface of intestine microvilli in Haemonchus contortus was identified as the most effective antigen candidate. However, its recombinant forms produced in Escherichiacoli, insect cells and yeast could not provide promising protection against H. contortus challenge, probably due to the inappropriate glycosylation and/or conformational folding. Herein, partial H11 containing the potential zinc-binding domain and two predicted glycosylation sites (nt 1 bp-1710 bp, Trans-HPS) was subcloned downstream of 5' flanking region of Caenorhabditis elegans cpr-1 gene in pPD95.77 vector, with the deletion of GFP gene. The recombinant was expressed in C. elegans and verified by blotting with anti-H11 and anti-Trans-HPS rabbit polyclonal antibodies and anti-His monoclonal antibody. Stably inherited Trans-HPS in worm descendants was achieved by integration using UV irradiation. Immunization with the crude Trans-HPS extracted from transgenic worms resulted in 37.71% reduction in faecal egg counts (FEC) (P<0.05) and 24.91% reduction in worm burden, but an upward curve with moderate rate of daily FEC in goats. These results suggested an apparent delay against H. contortus egg-laying in goats, which differed from that with bacteria-origin form of partial H11 (nt 670 bp-1710 bp, HPS) (26.04% reduction in FEC and 18.46% reduction in worm burden). These findings indicate the feasibility of sufficient C. elegans-expressed H11 for the immunological research and vaccine development.


Assuntos
Aminopeptidases/metabolismo , Caenorhabditis elegans/enzimologia , Endopeptidases/metabolismo , Haemonchus/enzimologia , Abomaso/parasitologia , Aminopeptidases/genética , Aminopeptidases/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Antígenos de Helmintos/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/imunologia , Endopeptidases/genética , Endopeptidases/imunologia , Fezes/parasitologia , Feminino , Regulação Enzimológica da Expressão Gênica , Cabras , Imunoglobulina G/sangue , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Contagem de Ovos de Parasitas , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
Parasite ; 21: 36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25075975

RESUMO

Cryptosporidium is one of the most important parasites in poultry, and this pathogen can infect more than 30 avian species. The present study investigated the infection rate of Cryptosporidium among broiler chicken flocks. A total of 385 fecal samples from broiler chickens in 7 regions of Zhejiang Province collected from November 2010 to January 2012 were examined by microscopy. Thirty-eight (10%) samples were positive for Cryptosporidium infection, and 3 genotypes (Cryptosporidium baileyi, Cryptosporidium meleagridis, and avian genotype II) were identified by PCR and sequencing. A phylogenetic tree of the isolates was analyzed. These results suggest that cryptosporidiosis is widespread in poultry in Zhejiang Province, and is a potential threat to public health as well as the economy. This is the first report about the infection rate and molecular characterization of Cryptosporidium in broiler chickens in Zhejiang.


Assuntos
Galinhas/parasitologia , Criptosporidiose/epidemiologia , Cryptosporidium/isolamento & purificação , DNA de Protozoário/isolamento & purificação , Oocistos/química , Doenças das Aves Domésticas/parasitologia , Animais , Sequência de Bases , China/epidemiologia , Criptosporidiose/parasitologia , Cryptosporidium/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Fezes/parasitologia , Parasitologia de Alimentos , Genes de Protozoários , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas/epidemiologia , Prevalência , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Ribotipagem , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA