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1.
J Antimicrob Chemother ; 79(7): 1606-1613, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38804142

RESUMO

BACKGROUND: The efficacy of current drugs against hookworms at a single dose is highly variable across regions, age groups and infection intensity. Extensive and repeated use of these drugs also leads to potential drug resistance. Therefore, novel drugs are required for sustained disease control. OBJECTIVES: Novel aromatic heterocycle substituted aminamidine derivatives (AADs) were synthesized based on tribendimine (TBD), and their in vivo potency against Necator americanus was tested. METHODS: The efficacy of the AADs was tested in male hamsters. Oral and IV pharmacokinetic parameters were determined in male Sprague-Dawley rats. The proteomic profiles of N. americanus samples treated with AADs were compared using tandem mass tag-based quantitative proteomic analyses. RESULTS: Most AADs exhibited better anthelmintic activity than TBD at a single oral dose. Compound 3c exhibited improved solubility (>50×), and the curative dose was as low as 25 mg/kg. Similar to TBD, 3c was rapidly metabolized after oral administration and transformed into p-(1-dimethylamino ethylimino)aniline (dADT), an active metabolite against intestinal nematodes. dADT from 3c had better pharmacokinetic profiles than that from TBD and achieved an oral bioavailability of 99.5%. Compound 3c possessed rapid anthelmintic activity, clearing all worms within 24 h after an oral dose of 50 mg/kg. Quantitative proteomic analysis indicated that it might be related to ATP metabolism and cuticle protein synthesis. CONCLUSIONS: Compound 3c is a novel and promising compound against N. americanus in vivo.


Assuntos
Anti-Helmínticos , Necator americanus , Ratos Sprague-Dawley , Animais , Masculino , Anti-Helmínticos/farmacologia , Anti-Helmínticos/farmacocinética , Necator americanus/efeitos dos fármacos , Amidinas/farmacologia , Amidinas/farmacocinética , Administração Oral , Cricetinae , Ratos , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/farmacocinética , Compostos Heterocíclicos/química , Proteômica
2.
PLoS Pathog ; 18(2): e1010233, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35108342

RESUMO

Schistosomiasis, which is caused by infection with Schistosoma spp., is characterized by granuloma and fibrosis in response to egg deposition. Pattern recognition receptors are important to sense invading Schistosoma, triggering an innate immune response, and subsequently shaping adaptive immunity. Cyclic GMP-AMP synthase (cGAS) was identified as a major cytosolic DNA sensor, which catalyzes the formation of cyclic GMP-AMP (cGAMP), a critical second messenger for the activation of the adaptor protein stimulator of interferon genes (STING). The engagement of STING by cGAMP leads to the activation of TANK-binding kinase 1 (TBK1), interferon regulatory factor 3 (IRF3), and the subsequent type I interferon (IFN) response. cGAS is suggested to regulate infectious diseases, autoimmune diseases, and cancer. However, the function of cGAS in helminth infection is unclear. In this study, we found that Cgas deficiency enhanced the survival of mice infected with S. japonicum markedly, without affecting the egg load in the liver. Consistently, Cgas deletion alleviated liver pathological impairment, reduced egg granuloma formation, and decreased fibrosis severity. In contrast, Sting deletion reduced the formation of egg granulomas markedly, but not liver fibrosis. Notably, Cgas or Sting deficiency reduced the production of IFNß drastically in mice infected with S. japonicum. Intriguingly, intravenous administration of recombinant IFNß exacerbated liver damage and promoted egg granuloma formation, without affecting liver fibrosis. Clodronate liposome-mediated depletion of macrophages indicated that macrophages are the major type of cells contributing to the induction of the type I IFN response during schistosome infection. Moreover, cGAS is important for type I IFN production and phosphorylation of TBK1 and IRF3 in response to stimulation with S. japonicum egg- or adult worm-derived DNA in macrophages. Our results clarified the immunomodulatory effect of cGAS in the regulation of liver granuloma formation during S. japonicum infection, involving sensing schistosome-derived DNA and producing type I IFN. Additionally, we showed that cGAS regulates liver fibrosis in a STING-type I-IFN-independent manner.


Assuntos
Interferon Tipo I/imunologia , Proteínas de Membrana/imunologia , Nucleotidiltransferases/imunologia , Esquistossomose Japônica/imunologia , Esquistossomose/imunologia , Esquistossomose/parasitologia , Animais , Feminino , Imunidade , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotidiltransferases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
3.
Microb Pathog ; 174: 105952, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36528327

RESUMO

Enterocytozoon bieneusi, Cryptosporidium spp. and Cyclospora cayetanensis are three important zoonotic pathogens which were a major cause of foodborne or waterborne intestinal diseases in humans and animals. However, very little data about occurrence and genotypes of the three parasites in Ningbo in the south wing of the Yangtze River Delta, China, which is important for a tourist city. In the present study, molecular characterization of E. bieneusi, C. cayetanensis and Cryptosporidium spp. in fecal samples from 489 diarrheal outpatients were carried out. As a result, a total of 35 (7.16%, 35/489) and three (0.61%, 3/489) samples were positive for E. bieneusi and C. cayetanensis respectively. No Cryptosporidium-positive sample or mixed-infections were detected. Four known E. bieneusi genotypes (Type IV, D, I and CHN4) and 8 novel genotypes (NBH1-NBH8) were identified with type IV was the dominant genotype (n = 14), followed by genotypes D (n = 5), NBH8 (n = 5) and NBH7 (n = 3). The remaining genotypes were found in one sample each, and these genotypes were belonged to the previously described high-potential zoonotic group 1. One novel sequence named NBC315, and the other two sequences (NBC30 and NBC370) identical with the reported sequence were detected. Therefore, the existence and importance of zoonotic potential of E. bieneusi and C. cayetanensis in diarrheal outpatients in Ningbo indicates the public health threats, and more investigations should be carried out in human populations, animals and other environmental sources from the One Health perspective.


Assuntos
Criptosporidiose , Cyclospora , Enterocytozoon , Animais , Humanos , Enterocytozoon/genética , Cyclospora/genética , Pacientes Ambulatoriais , China/epidemiologia , Genótipo , Diarreia/epidemiologia , Fezes/parasitologia , Filogenia , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Prevalência
4.
Microb Pathog ; 181: 106219, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37391101

RESUMO

BACKGROUND: Blastocystis is one of the important zoonotic parasites which can infect humans and various animals worldwide and has become a growing global public health concern. The study aims to obtain the data of Blastocystis infection and the information of the genetic characteristic. METHODS: In the present study, 489 fecal samples were collected from diarrhea outpatients in Ningbo, Zhejiang province, and were examined the presence of Blastocystis by polymerase chain reaction combined with sequencing. RESULTS: A total of 10 samples (2.04%, 10/489) were positive for Blastocystis with no significant difference among sex and age groups, respectively. Eight samples were successfully sequenced, and five zoonotic ST3 and three zoonotic ST1 with two new sequences were identified. CONCLUSIONS: We first demonstrated the occurrence of Blastocystis infection in diarrhea outpatients in Ningbo, with two zoonotic subtypes (ST1 and ST3) and two new sequences being characterized. Meanwhile, mixed infection of Blastocystis and E. bieneusi was found which indicates the importance of investigation of multiple parasites. Finally, more extensive studies will be needed to better understand the transmission of Blastocystis at human-animal-environment interface and provide evidence for the development of one health strategies for the prevention and control of such diseases.


Assuntos
Infecções por Blastocystis , Blastocystis , Animais , Humanos , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Pacientes Ambulatoriais , Variação Genética , Blastocystis/genética , China/epidemiologia , Fezes/parasitologia , Diarreia/epidemiologia , Prevalência , Filogenia
5.
Appl Microbiol Biotechnol ; 107(17): 5317-5328, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37428188

RESUMO

Glucoside compounds are widely found in nature and have garnered significant attention in the medical, cosmetics, and food industries due to their diverse pharmaceutical properties, biological activities, and stable application characteristics. Glycosides are mainly obtained by direct extraction from plants, chemical synthesis, and enzymatic synthesis. Given the challenges associated with plant extraction, such as low conversion rates and the potential for environmental pollution with chemical synthesis, our review focuses on enzymatic synthesis. Here, we reviewed the enzymatic synthesis methods of 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G), 2-O-α-D-glucosyl glycerol (α-GG), arbutin and α-glucosyl hesperidin (Hsp-G), and other glucoside compounds. The types of enzymes selected in the synthesis process are comprehensively analyzed and summarized, as well as a series of enzyme transformation strategies adopted to improve the synthetic yield. KEY POINTS: • Glycosyl compounds have applications in the biomedical and food industries. • Enzymatic synthesis converts substrates into products using enzymes as catalysts. • Substrate bias and specificity are key to improving substrate conversion.


Assuntos
Ácido Ascórbico , Glucosídeos , Arbutina
6.
Microb Pathog ; 154: 104823, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689811

RESUMO

Cryptosporidium spp. and Enterocytozoon bieneusi are common and important enteric parasites that can infect humans and animals, causing diarrhoea and systemic diseases. The objectives of the present study were to examine the prevalence and genetic variations of Cryptosporidium and E. bieneusi in pigs transferred from northeastern China to Ningbo city in Zhejiang Province. Cryptosporidium spp. was detected in 0.9% (2/216) of these samples and belonged to the zoonotic species Cryptosporidium parvum. A high E. bieneusi infection rate (25.0%, 54/216) was observed in this study, with 7 possible novel ITS genotypes (JLNB-1 to JLNB-7) and 10 known genotypes (EbpA, CM11, H, CM6, pigEBITS1, EbpC, CS-4, pigEBITS5, CHS5, and Henan-Ⅳ) identified, and zoonotic EbpA was the dominant genotype. Genotypes H and pigEBITS1 were reported for the first time in pigs in China. Phylogenetic analysis indicated that all the genotypes found in these samples belonged to zoonotic group 1. These findings indicated the potential threat of Cryptosporidium and E. bieneusi to humans or the environment during cross-regional transportation. An effective management control system should be built to avoid parasitic transmission as well as other animal diseases while travelling across different regions. In further studies, attention should be given to the transmission routes and the role of pigs as a potential source of human Cryptosporidium and E. bieneusi infections in China.


Assuntos
Criptosporidiose , Cryptosporidium , Enterocytozoon , Microsporidiose , Animais , China/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Enterocytozoon/genética , Fezes , Genótipo , Microsporidiose/epidemiologia , Microsporidiose/veterinária , Filogenia , Prevalência , Suínos , Zoonoses
7.
Parasite Immunol ; 43(10-11): e12871, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34037255

RESUMO

Gamma-delta (γδ) T cells are the bridge between natural and adaptive immunity. In the present study, peripheral blood was collected from 13 patients with advanced schistosomiasis (schistosomiasis group) and 13 uninfected people (control group) to investigate the γδ T cells and their subtypes in human schistosomiasis. Compared with the control group, the proportion of Vδ1 cells and CD27+ Vδ1+ cells in the schistosomiasis group increased significantly, while CD27- cells and CD27- Vδ1- cells decreased. Only the level of IL-17A differed between the groups, being significantly decreased in the schistosomiasis group. In the schistosomiasis group, there were no correlations between the liver fibrosis and subsets of γδ T cells, or the level of cytokines. Additionally, the level of IL-17A correlated positively with the proportion of CD27- Vδ1- cells. Thus, there was a higher frequency of circulating Vδ1 γδT cells in patients with advanced schistosomiasis. The decreased IL-17A might be related to the reduction in CD27- Vδ1- cell.


Assuntos
Receptores de Antígenos de Linfócitos T gama-delta , Esquistossomose , Citocinas , Humanos , Cirrose Hepática , Subpopulações de Linfócitos T
8.
Parasitology ; 148(11): 1360-1365, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34100347

RESUMO

Giardia duodenalis is a common zoonotic intestinal pathogen. It has been increasingly reported in humans and animals; however, genotyping information for G. duodenalis in captive animals is still limited. This study was conducted to assess the prevalence and multilocus genotyping of G. duodenalis in captive animals in zoological gardens in Shanghai, China. A total of 678 fresh fecal samples were randomly collected from captive animals including non-human primates (NHPs) (n = 190), herbivores (n = 190), carnivores (n = 151), birds (n = 138) and reptiles (n = 9) in a zoo and were examined for the presence of G. duodenalis using nested polymerase chain reaction (nested PCR). All G. duodenalis positive samples were assayed with PCR followed by sequencing at ß-giardin (bg), glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) genes. In this study, 42 specimens (6.2%) were tested G. duodenalis-positive of the 678 fecal samples examined based on a single locus. A total of 30 (4.4%), 30 (4.4%) and 22 (3.2%) specimens were successfully amplified and sequenced at gdh, tpi and bg loci, respectively. Assemblages A and B were identified with assemblage B dominating in NHPs. Sequence analysis demonstrated that one, two and five new isolates were identified at bg, gdh and tpi loci. DNA sequences and new assemblage-subtypes of zoonotic G. duodenalis assemblages A and B were identified in the current study. Our data indicate the occurrence and molecular diversity of G. duodenalis and the potential zoonotic transmission in captive animals in China.


Assuntos
Animais de Zoológico/parasitologia , Giardia lamblia/classificação , Giardíase/veterinária , Zoonoses/parasitologia , Animais , Sequência de Bases , China/epidemiologia , DNA de Protozoário/química , Fezes/parasitologia , Técnicas de Genotipagem/veterinária , Giardia lamblia/genética , Giardia lamblia/isolamento & purificação , Giardíase/epidemiologia , Giardíase/parasitologia , Giardíase/transmissão , Prevalência , Alinhamento de Sequência/veterinária , Zoonoses/epidemiologia , Zoonoses/transmissão
9.
Parasitology ; 148(9): 1019-1029, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33896429

RESUMO

Echinococcus granulosus sensu lato (s.l.) is a zoonotic parasite that causes cystic echinococcosis (CE) in humans. However, E. granulosus sensu stricto (s.s.) is considered the predominant species in CE infections worldwide. According to the population genetic diversity and structure of E. granulosus s.l., gene flow can explain the parasite drift among the neighbouring countries of Pakistan. The mitochondrial (mt) co1 (n = 47), nadh1 (n = 37) and cytb (n = 35) nucleotide sequences of E. granulosus s.l. isolates from Pakistan, Iran, China and India were retrieved from the National Centre for Biotechnology Information database to determine the genealogical relationships. The sequences were grouped as the mt-co1 (genotypes G1 and G3, G6-G7), mt-cytb (genotypes G1 and G3), and mt-nadh1(genotypes G1 and G3). The data were analysed using bioinformatic tools. A total of 19 polymorphic sites for the mt-co1 sequence (374 bp) were observed of which 31.6% (6/19) were parsimony-informative sites. Unique singleton haplotypes within the E. granulosus s.s. haplotype network based on the mt-co1 gene were highly prevalent (68.4%; 13/19) in Pakistani isolates followed by Chinese, Indian and Iranian isolates; four polymorphic sites were detected in the E. canadensis (G6/G7). In E. canadensis mt-co1 haplotype network, 75% (3/4) unique singleton haplotypes were from the Iranian isolates. Twelve polymorphic sites were found using the mt-cytb sequence (547 bp); 25% (3/12) were parsimony-informative and there were 66.7% (8/12) unique singleton haplotypes within the mt-cytb haplotype network in E. granulosus s.s. with the most reported from Pakistan followed by Iran and China. 20 polymorphic sites were detected in E. granulosus s.s. mt-nadh1 sequences (743 bp); 20% (4/20) were parsimony-informative. There were 66.7% (8/12) main single haplotypes within the mt-nadh1 haplotype network, with the most reported from Pakistan followed by that from India, Iran and China. The sequence analyses show low nucleotide diversity and high haplotype diversity in general.


Assuntos
Citocromos b/genética , Echinococcus granulosus/crescimento & desenvolvimento , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Helmintos , Genes Mitocondriais , Proteínas de Helminto/genética , NAD/genética , Animais , China , Haplótipos , Índia , Irã (Geográfico) , Paquistão
10.
Anal Chem ; 92(12): 8607-8613, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32393021

RESUMO

Photoelectrochemical sensing has developed rapidly in the past decade because of its inherent advantages of economic devices and low background noise. However, traditional assembly of photoelectric beacons, probes, and targets on the ITO electrode solid-liquid interface inevitably leads to time-consuming, limited selectivity, poor stability, and nonreproducibility. To overcome these drawbacks, in this work, a unique split-type PEC aptasensor for carcinoembryonic antigen (CEA) was developed in virtue of the sandwich-like structure comprised of magnetic-optical Fe3O4@SiO2@CdS-DNA1, CEA aptamer, and signal element SiO2-Au-DNA2. The sandwich-like structure is easily formed in the liquid phase and can be triggered by competition from low-abundance CEA, resulting in dissociation. By further photocurrent measurement in pure phosphate buffer saline (PBS), coexisting species can be effectively removed from the modified electrode, improving selectivity, stability, and repeatability. These advantages benefit from the preparation of uniform and monodispersed Fe3O4@SiO2@CdS and SiO2-Au particles, DNAs assembly, and an elegant design. Additionally, the as-designed signal-on PEC aptasensor is highly sensitive, short time-consuming, and economical, enabling the detection of CEA in serum specimens. It not only provides an alternative to CEA immunosensors, but also paves the way for high-performance PEC aptasensors.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Antígeno Carcinoembrionário/análise , Técnicas Eletroquímicas , Nanoestruturas/química , Compostos de Cádmio/química , DNA/química , Humanos , Nanopartículas Magnéticas de Óxido de Ferro/química , Tamanho da Partícula , Processos Fotoquímicos , Dióxido de Silício/química , Sulfetos/química , Propriedades de Superfície
11.
BMC Microbiol ; 20(1): 10, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931704

RESUMO

BACKGROUND: Intestinal pathogen infections are widespread among impoverished populations. Enterocytozoon bieneusi is the most common pathogen of intestinal microsporidian species in humans worldwide. However, no epidemiological information is available on E. bieneusi infection in humans in Myanmar. The present study comprised the first identification and genotyping of E. bieneusi in humans conducted in Myanmar. RESULTS: A total of 172 fecal specimens were collected from the Wa people (one each) in four villages of Pangsang Township of the Matman District of Shan State, Myanmar, and each participant completed a questionnaire. E. bieneusi was identified and genotyped using polymerase chain reaction (PCR) and sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene. The average prevalence of E. bieneusi was 8.72% (15/172), ranging from 3.85 to 13.89% by village. E. bieneusi infection was not related to any of the risk factors studied. Six genotypes were identified, comprising two known genotypes Peru6 (n = 10) and D (n = 1) and four novel genotypes (MMR23, MMR25, MMR86, and MMR87) (one each), and two people infected with genotype Peru6 were from the same family. A phylogenetic analysis based on a neighbor-joining tree of the ITS sequences of E. bieneusi indicated that all the six genotypes were clustered into group 1. CONCLUSIONS: This is the first identification and genotyping of E. bieneusi in humans in Myanmar. The observations that the two people infected with genotype Peru6 were from the same family, and that all six genotypes obtained in the present study fell into zoonotic group 1, showed the potential for anthropogenic and zoonotic transmissions. The present data argue for the importance of epidemiological control and prevention from medical sectors.


Assuntos
DNA Ribossômico/genética , Enterocytozoon/classificação , Técnicas de Genotipagem/métodos , Microsporidiose/diagnóstico , Zoonoses/microbiologia , Adolescente , Adulto , Animais , Criança , DNA Fúngico/genética , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Fezes/microbiologia , Feminino , Genótipo , Humanos , Masculino , Mianmar , Filogenia , Análise de Sequência de DNA , Inquéritos e Questionários , Adulto Jovem
12.
BMC Infect Dis ; 20(1): 262, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245373

RESUMO

BACKGROUND: Echinococcosis is a zoonotic parasitic disease causing serious health problems in both humans and animals in different endemic regions across the world. There are two different forms of human echinococcosis: Cystic Echinococcosis (CE) and Alveolar Echinococcosis (AE). CE is caused by the larval stage of Echinococcus granulosus sensu lato and AE by the larval stage of Echinococcus multilocularis. Geographically, CE is universally distributed, while AE is prevalent in the northern hemisphere. Although the disease is endemic in neighboring countries (China, Iran and India) of Pakistan, there are limited reports from that country. Besides, there are no comprehensive data on the genotyping of Echinococcus species in humans based on sequence analysis. This study aimed to detect the presence of human CE and to identify Echinococcus spp. in human isolates through genetic characterization of hydatid cysts in the Punjab Province of Pakistan. METHODS: Genetic analysis was performed on 38 human hydatid cyst samples collected from patients with echinococcosis using mitochondrial cytochrome c oxidase subunit 1 (cox1), cytochrome b (cytb) and NADH subunit 1 (nad1). Patient data including age, epidemiological history, sex, and location were obtained from hospital records. RESULTS: According to the sequence analysis we detected E. granulosus sensu stricto (n = 35), E. canadensis (G6/G7) (n = 2), and E. multilocularis (n = 1). Thus, the majority of the patients (92.1%, 35/38) were infected with E. granulosus s.s. This is the first molecular confirmation of E. canadensis (G6/G7) and E. multilocularis in human subjects from Pakistan. CONCLUSIONS: These findings suggested that E. granulosus s.s. is the dominant species in humans in Pakistan. In addition, E. canadensis (G6/G7) and E. multilocularis are circulating in the country. Further studies are required to explore the genetic diversity in both humans and livestock.


Assuntos
Equinococose/epidemiologia , Echinococcus granulosus/genética , Echinococcus multilocularis/genética , Análise de Sequência/métodos , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Ciclo-Oxigenase 1/genética , Citocromos b/genética , Equinococose/parasitologia , Echinococcus granulosus/isolamento & purificação , Echinococcus multilocularis/isolamento & purificação , Complexo I de Transporte de Elétrons/genética , Feminino , Genótipo , Humanos , Gado/parasitologia , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Filogenia , Adulto Jovem , Zoonoses/parasitologia
13.
BMC Infect Dis ; 20(1): 16, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31910816

RESUMO

BACKGROUND: Cryptosporidium is a genus of common intestinal protozoa, members of which cause diarrhea in a wide variety of hosts. Previous studies on Cryptosporidium in China have mainly focused on diarrhea sufferers, children, and immunodeficient individuals such as HIV/AIDS patients. However, the epidemiological characteristics of Cryptosporidium in the population in rural areas remain unclear. Herein, we investigated the prevalence of, and risk factors for, Cryptosporidium in rural areas of Binyang County, Guangxi Zhuang Autonomous Region, China, and genetically characterized the Cryptosporidium isolates we obtained. METHODS: From August to December 2016, two villages in Binyang County, Guangxi, were sampled using a random cluster sampling method. Fresh fecal samples were collected from all eligible residents (residence time > 6 months). Molecular characterization of Cryptosporidium was carried out based on its SSU rRNA, gp60, actin and hsp70 gene sequences. Fisher's exact test were conducted to assess the risk factors for Cryptosporidium infection. RESULTS: A total of 400 fecal samples were collected from 195 males (48.8%) and 205 females (51.2%). Two samples (0.5%) were positive for Cryptosporidium and were identified as C. viatorum and C. occultus respectively. Moreover, a new C. viatorum subtype XVaA3h was identified based on the sequence of the gp 60 gene. CONCLUSIONS: To our knowledge, this is the first report of C. viatorum and C. occultus infections in humans in China and of C. viatorum subtype XVaA3h. The findings provide important information on the prevalence of Cryptosporidium in the Chinese population, and expand the range of Cryptosporidium species known to infect people in China.


Assuntos
Sequência de Bases/genética , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , DNA de Protozoário/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Diarreia/parasitologia , Fezes/parasitologia , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
14.
Infect Immun ; 87(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30642905

RESUMO

Cryptosporidium, a protozoan parasite that infects the gastrointestinal epithelium and other mucosal surfaces in humans and animals, is an important opportunistic pathogen in AIDS patients and one of the most common enteric pathogens affecting young children in developing regions. This parasite is referred to as a "minimally invasive" mucosal pathogen, and epithelial cells play a central role in activating and orchestrating host immune responses. We previously demonstrated that Cryptosporidium parvum infection stimulates host epithelial cells to release exosomes, and these released exosomes shuttle several antimicrobial peptides to carry out anti-C. parvum activity. In this study, we detected the upregulation of inflammatory genes in the liver and spleen following C. parvum intestinal infection in neonatal mice. Interestingly, exosomes released from intestinal epithelial cells following C. parvum infection could activate the nuclear factor kappa B signaling pathway and trigger inflammatory gene transcription in isolated primary splenocytes. Several epithelial cell-derived proteins and a subset of parasite RNAs were detected in the exosomes released from C. parvum-infected intestinal epithelial cells. Shuttling of these effector molecules, including the high mobility group box 1 protein, was involved in the induction of inflammatory responses in splenocytes induced by the exosomes released from infected cells. Our data indicate that exosomes released from intestinal epithelial cells upon C. parvum infection can activate immune cells by shuttling various effector molecules, a process that may be relevant to host systemic responses to Cryptosporidium infection.


Assuntos
Criptosporidiose/imunologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/fisiologia , Células Epiteliais/imunologia , Exossomos/imunologia , Intestinos/imunologia , Baço/citologia , Animais , Criptosporidiose/genética , Células Epiteliais/parasitologia , Exossomos/genética , Feminino , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/imunologia , Humanos , Intestinos/parasitologia , Fígado/imunologia , Fígado/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/genética , NF-kappa B/imunologia , Baço/imunologia , Baço/parasitologia
15.
Parasitology ; 146(9): 1199-1205, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31084658

RESUMO

Giardia duodenalis is a common intestinal parasite in humans and other mammals, and it causes major public and veterinary health problems worldwide. China is a major pig-raising country, and studies on Giardia in pigs have important public health significance. The present study was conducted to investigate the prevalence of Giardia and assess its genetic characterization. A total of 93 samples were collected from two farms in Shanghai. The presence of Giardia was determined using PCR and sequence analysis of glutamate dehydrogenase, beta-giardin and triose phosphate isomerase genes. The average prevalence of G. duodenalis infection was 26.88% (25/93) in the pigs, with 28.13% (18/64) in farm 1 vs 24.14% (7/29) in farm 2. All the PCR-positive products were successfully sequenced, and assemblage E was more prevalent. Zoonotic assemblages A and B and canine-specific assemblage C were identified in farm 1, whereas, only assemblage E was detected in farm 2. Interestingly, two pig isolates showed 100% homology with human-derived isolates from Australia and China at the bg and tpi loci respectively. Pigs infected with Giardia infect humans by polluting the environment; whether pigs are a potential environmental source of the human pathogen in China requires more epidemiological data.


Assuntos
Genótipo , Giardia lamblia/classificação , Giardíase/veterinária , Tipagem de Sequências Multilocus , Doenças dos Suínos/parasitologia , Animais , China/epidemiologia , Proteínas do Citoesqueleto/genética , Fazendas , Fezes/parasitologia , Variação Genética , Giardíase/epidemiologia , Glutamato Desidrogenase/genética , Humanos , Filogenia , Prevalência , Proteínas de Protozoários/genética , Suínos/parasitologia , Doenças dos Suínos/epidemiologia , Triose-Fosfato Isomerase/genética
16.
BMC Immunol ; 19(1): 29, 2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30355335

RESUMO

BACKGROUND: Excretory-secretory products released by Echinococcus granulosus protoscoleces (EgPSC-ESPs) are well-known to regulate T cell responses. However, their direct influence on the differentiation of B cell subsets remains largely elusive. This study investigated the effects of EgPSC-ESPs on the differentiation of IL-10-producing B cells (B10), and explored the possible role of Toll-like receptor 2 (TLR-2) signaling in this process. RESULTS: In comparison to phosphate buffered saline (PBS), B cells exposed to the excretory-secretory products (ESPs) generated higher percentages of B10 cells, with higher expression of IL-10 mRNA, and larger amount of IL-10 production, which were in a dose dependent way. The mRNA and protein expression of TLR-2 in the ESPs-stimulated B cells were significantly higher than those in PBS, which was consistent to the results in B cells isolated from EgPSC infected mice. Moreover, TLR-2-/- B cells in response to ESPs stimulation expressed lower levels of IL-10 mRNA and produced undetectable IL-10 in comparison to those in normal B cells. In addition, Phosphatase and tensin homolog deleted on chromosome ten/AKT/Phosphatidylinositol-3 kinase (PTEN/AKT/PI3K) pathway was activated in ESPs-treated B cells, which was also dependent on TLR-2 signaling. Pam3CSK4, the agonist of TLR-2, could mock the effects of ESPs on the expression of PTEN, AKT and PI3K. CONCLUSION: Overall, this study revealed that TLR-2 signaling was required for B10 induction mediated by EgPSC-ESPs, which might be an immunomodulatory target against the parasite infection.


Assuntos
Antígenos de Helmintos/imunologia , Subpopulações de Linfócitos B/imunologia , Equinococose/imunologia , Echinococcus granulosus/imunologia , Interleucina-10/metabolismo , Receptor 2 Toll-Like/metabolismo , Animais , Interleucina-10/genética , Camundongos Endogâmicos C57BL , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor 2 Toll-Like/genética
17.
Cell Physiol Biochem ; 51(3): 1207-1220, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30481745

RESUMO

BACKGROUND/AIMS: This study aims to predict the pro-angiogenic functions of monocytic-type myeloid-derived suppressor cells (M-MDSCs) derived from mice infected with Echinococcus granulosus. METHODS: M-MDSCs were collected from Balb/c mice infected with E. granulosus and normal mice (control) and cultured in vitro. Human umbilical vein endothelial cells (HUVECs) were stimulated with the cell supernatant, and angiogenesis was investigated and analysed by the Angiogenesis module of the software NIH Image J. RNA was extracted from fresh isolated M-MDSCs and analysed with miRNA microarray; differentially expressed miRNAs and their potential functions were analysed through several bioinformatics tools. Finally, quantitative PCR was used to confirm the results of microarray analysis. RESULTS: M-MDSCs from mice infected with E. granulosus could promote the formation of tubes from HUVECs in vitro. Moreover, vascular endothelial growth factor (VEGF) showed significantly high expression, whereas soluble fms-like tyrosine kinase-1 (sFlt-1) showed low expression at the transcriptional level in M-MDSCs from mice infected with E. granulosus. Microarray analysis of miRNAs showed that 28 miRNAs were differentially expressed in M-MDSCs from the two experimental mice groups, and 272 target genes were predicted using the microRNA databases TargetScan, PITA and microRNAorg. These target genes were mainly involved in the biological processes of intracellular protein transport, protein targeting to the lysosome and protein transport, and mainly located in the cytoplasm, neuronal cell body and membrane. Moreover, they were mainly involved in the molecular functions of protein binding, metal ion binding and SH3 domain binding. Further, the differentially expressed miRNAs were mainly enriched in the endocytosis, Wnt and axon guidance pathways, as well as the MAPK, focal adhesion, PI3K-Akt, cAMP, mTOR and TGF-ß signalling pathways, which are linked to immunoregulation and angiogenesis based on the results of bioinformatics analysis with DIANA-miRPath 3.0. In addition, the expression of eight miRNAs was randomly verified by quantitative PCR independently in three mice infected with E. granulosus and three normal mice. CONCLUSION: M-MDSCs have a potential angiogenic role during E. granulosus infection, and miRNAs may play a role in the immune response and angiogenesis functions of M-MDSCs through regulation of the identified signalling pathways.


Assuntos
Equinococose/genética , Echinococcus granulosus/fisiologia , Regulação da Expressão Gênica , MicroRNAs/genética , Células Supressoras Mieloides/virologia , Neovascularização Patológica/genética , Animais , Células Cultivadas , Equinococose/patologia , Equinococose/virologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Células Supressoras Mieloides/patologia , Neovascularização Patológica/patologia , Neovascularização Patológica/virologia , Fator A de Crescimento do Endotélio Vascular/genética
18.
Chemistry ; 24(27): 6950-6957, 2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29411451

RESUMO

Because of their structural and compositional flexibility, perovskite oxides represent an attractive alternative electrocatalyst class to precious metals for the oxygen reduction reaction (ORR); an important reaction in fuel cells and metal-air batteries. Partial replacement of the original metal cation with another cation, namely, doping, can be used to tailor the ORR activity of perovskite, for which a metal has been exclusively used as the dopant component in the past. Herein, phosphorus is proposed as a non-metal dopant for the cation site to develop a new perovskite family with the formula of La0.8 Sr0.2 Mn1-x Px O3-δ (x=0, 0.02, 0.05, and 0.1; denoted as LSM, LSMP0.02, LSMP0.05, and LSMP0.1, respectively). Powder XRD patterns reveal that the solubility of phosphorus in the perovskite structure is around 0.05. Rotating ring-disk electrode experiments in the form of linear-sweep voltammetry scans demonstrated the best ORR performance for LSMP0.05, and also revealed close to a four-electron ORR pathway for all four compositions. A chronoamperometric test (9000 s) and 500 cycle accelerated durability test demonstrated higher durability for LSMP0.05 relative to that of LSM and the commercial 20 wt % Pt/C catalyst. The higher ORR activity for LSMP0.05 is attributed to the optimised average valence of Mn, as evidenced by combined X-ray photoelectron spectroscopy and soft X-ray absorption spectroscopy data. Doping phosphorus into perovskites is an effective way to develop high-performance electrocatalysts for ORR.

19.
Infect Immun ; 85(8)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28507072

RESUMO

Conventional adaptive T cell responses contribute to the pathogenesis of Schistosoma japonicum infection, leading to liver fibrosis. However, the role of gamma-delta (γδ) T cells in this disease is less clear. γδ T cells are known to secrete interleukin-17 (IL-17) in response to infection, exerting either protective or pathogenic functions. In the present study, mice infected with S. japonicum are used to characterize the role of γδ T cells. Combined with the infection of S. japonicum, an extremely significant increase in the percentage of neutrophils in the CD45+ cells was detected (from approximately 2.45% to 46.10% in blood and from 0.18% to 7.34% in spleen). Further analysis identified two different γδ T cell subsets that have different functions in the formation of granulomas in S. japonicum-infected mice. The Vγ1 T cells secrete gamma interferon (IFN-γ) only, while the Vγ2 T cells secrete both IL-17A and IFN-γ. Both subtypes lose the ability to secrete cytokine during the late stage of infection (12 weeks postinfection). When we depleted the Vγ2 T cells in infected mice, the percentage of neutrophils in blood and spleen decreased significantly, the liver fibrosis in the granulomas was reduced, and the level of IL-17A in the serum decreased (P < 0.05). These results suggest that during S. japonicum infection, Vγ2 T cells can recruit neutrophils and aggravate liver fibrosis by secreting IL-17A. This is the first report that a subset of γδ T cells plays a partial role in the pathological process of schistosome infection.


Assuntos
Cirrose Hepática/imunologia , Cirrose Hepática/microbiologia , Neutrófilos/imunologia , Schistosoma japonicum/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Citocinas/imunologia , Interferon gama/imunologia , Interleucina-17/imunologia , Cirrose Hepática/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T gama-delta/imunologia
20.
BMC Infect Dis ; 17(1): 684, 2017 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-29029610

RESUMO

BACKGROUND: Enterocytozoon bieneusi has been increasingly reported to infect humans and various mammals. Microsporidia cause diarrhea in HIV-infected patients worldwide. PCR amplification and sequencing based on the internal transcribed spacer region have been used to describe the genotypes of E. bieneusi and transmission of microsporidiosis. METHODS: In this study, we examined E. bieneusi infection and genotypes in HIV-positive patients in Guangxi, China. Stool specimens were collected from 285 HIV-positive patients and 303 HIV-negative individuals. E. bieneusi genotypes were characterized using nested PCR and sequencing. RESULTS: Thirty-three (11.58%) HIV-positive patients were infected with microsporidia, and no infection was found in the 303 healthy controls. Three new genotypes were identified and named as GX25, GX456, and GX458; four known genotypes, PigEBITS7, Type IV/K, D, and Ebpc, were also identified. Our data showed that the positive rate for microsporidia was significantly higher in the rural patients than in the other occupation groups. In addition, the positive rate for microsporidia was significantly higher in the patients who drink unboiled water than in those with other drinking water sources. CONCLUSIONS: Our results will provide baseline data for preventing and controlling E. bieneusi infection in HIV/AIDS patients. Further studies are required to clarify the epidemiology and potential sources of microsporidia. Our study showed that microsporidium infection occurs in the HIV/AIDS patients in Guangxi, China.


Assuntos
Enterocytozoon/genética , Infecções por HIV/diagnóstico , Microsporidiose/diagnóstico , Adulto , Animais , China/epidemiologia , DNA Fúngico/química , DNA Fúngico/isolamento & purificação , DNA Fúngico/metabolismo , Enterocytozoon/classificação , Enterocytozoon/isolamento & purificação , Fezes/microbiologia , Feminino , Genótipo , Infecções por HIV/complicações , Humanos , Masculino , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Fatores de Risco , Análise de Sequência de DNA
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