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1.
PLoS One ; 17(8): e0271640, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35913975

RESUMO

Entamoeba are amoeboid extracellular parasites that represent an important group of organisms for which the regulatory networks must be examined to better understand how genes and functional processes are interrelated. In this work, we inferred the gene regulatory networks (GRNs) in four Entamoeba species, E. histolytica, E. dispar, E. nuttalli, and E. invadens, and the GRN topological properties and the corresponding biological functions were evaluated. From these analyses, we determined that transcription factors (TFs) of E. histolytica, E. dispar, and E. nuttalli are associated mainly with the LIM family, while the TFs in E. invadens are associated with the RRM_1 family. In addition, we identified that EHI_044890 regulates 121 genes in E. histolytica, EDI_297980 regulates 284 genes in E. dispar, ENU1_120230 regulates 195 genes in E. nuttalli, and EIN_249270 regulates 257 genes in E. invadens. Finally, we identified that three types of processes, Macromolecule metabolic process, Cellular macromolecule metabolic process, and Cellular nitrogen compound metabolic process, are the main biological processes for each network. The results described in this work can be used as a basis for the study of gene regulation in these organisms.


Assuntos
Entamoeba histolytica , Entamoeba , Entamebíase , Parasitos , Animais , Entamoeba/genética , Entamoeba histolytica/genética , Entamebíase/genética , Entamebíase/parasitologia , Fezes/parasitologia
2.
mSphere ; 7(4): e0029922, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35943216

RESUMO

Entamoeba histolytica, a protozoan parasite, causes amoebiasis, which is a global public health problem. The major route of infection is oral ingestion of cysts, the only form that is able to transmit to a new host. Cysts are produced by cell differentiation from proliferative trophozoites in a process termed "encystation." During encystation, cell morphology is markedly changed; motile amoeboid cells become rounded, nonmotile cells. Concomitantly, cell components change and significant fluctuations of metabolites occur. Cholesteryl sulfate (CS) is a crucial metabolite for encystation. However, its precise role remains uncertain. To address this issue, we used in vitro culture of Entamoeba invadens as the model system for the E. histolytica encystation study and identified serum-free culture conditions with CS supplementation at concentrations similar to intracellular CS concentrations during natural encystation. Using this culture system, we show that CS exerts pleiotropic effects during Entamoeba encystation, affecting cell rounding and development of membrane impermeability. CS dose dependently induced and maintained encysting cells as spherical maturing cysts with almost no phagocytosis activity. Consequently, the percentage of mature cysts was increased. CS treatment also caused time- and dose-dependent development of membrane impermeability in encysting cells via induction of de novo synthesis of dihydroceramides containing very long N-acyl chains (≥26 carbons). These results indicate that CS-mediated morphological and physiological changes are necessary for the formation of mature cysts and the maintenance of the Entamoeba life cycle. Our findings also reveal important morphological aspects of the process of dormancy and the control of membrane structure. IMPORTANCE Entamoeba histolytica causes a parasitic infectious disease, amoebiasis. Amoebiasis is a global public health problem with a high occurrence of infection and inadequate clinical options. The parasite alternates its form between a proliferative trophozoite and a dormant cyst that enables the parasite to adapt to new environments. The transition stage in which trophozoites differentiate into cysts is termed "encystation." Cholesteryl sulfate is essential for encystation; however, its precise role remains to be determined. Here, we show that cholesteryl sulfate is a multifunctional metabolite exerting pleiotropic roles during Entamoeba encystation, including the rounding of cells and the development of membrane impermeability. Such morphological and physiological changes are required for Entamoeba to produce cysts that are transmissible to a new host, which is essential for maintenance of the Entamoeba life cycle. Our findings are therefore relevant not only to Entamoeba biology but also to general cell and lipid biology.


Assuntos
Amebíase , Cistos , Entamoeba histolytica , Entamoeba , Estruturas Celulares , Ésteres do Colesterol , Entamoeba/metabolismo , Humanos
3.
Parasitol Int ; 91: 102638, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35926695

RESUMO

This study performed a cross-sectional investigation on the prevalence of Entamoeba complex infection comprising Entamoeba histolytica, Entamoeba dispar, and Entamoeba moshkovskii and their associated risk factors among the Orang Asli school children in three districts in Perak, Malaysia. Stool samples collected from 544 school children aged between 7 and 12 years old were examined through the nested multiplex PCR assay. The univariate and multivariate regression analyses were then carried out to determine the risk factor associated with Entamoeba complex infection. The overall prevalence of Entamoeba complex infections (E. histolytica, E. dispar and E. moshkovskii) was 21.3% (116/544). Most positive school children were infected with E. moshkovskii (10.7%; 58/544), followed by E. dispar (9.0%; 49/544) and E. histolytica (5.0%; 27/544). Not washing their hands after using the toilet was identified as the only significant risk factor for E. histolytica. The significant risk factors associated with E. moshkovskii infection included children within the age of 10-12 years old, with high BMI, living with working and non-educated mothers, no toilet in the house, not washing their hands after using the toilet, and fever. On the other hand, drinking water from the river, well, and rain was associated with a decreased risk of E. dispar infection. In conclusion, this study showed a high prevalence of Entamoeba spp. infections among the Orang Asli school children in Perak, Malaysia. Addressing the identified risk factors coupled with a holistic approach in breaking the transmission of Entamoeba complex can help improve their quality of life.


Assuntos
Entamoeba histolytica , Entamoeba , Entamebíase , Criança , Estudos Transversais , Entamoeba/genética , Entamebíase/epidemiologia , Fezes , Humanos , Malásia/epidemiologia , Prevalência , Qualidade de Vida , Fatores de Risco
4.
Arch Razi Inst ; 77(1): 87-93, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35891719

RESUMO

Trichomonas tenax (T. tenax) and Entamoeba gingivalis (E. gingivalis) are two oral protozoan parasites that are universal and found in patients with poor oral hygiene, as well as chronic and periodontal diseases. This study was conducted to assess the efficacy of some parameters, such as age, gender, education, residency, smoking, and dental cleaning routines, on the incidence of these parasites in the oral cavity of the patients participating in this study. A total of 230 individuals with chronic diseases, 97 of whom were patients (44 females and 53 males) participated in the present study. Dental plaque and saliva samples were collected from each patient and examined under light microscopy with Giemsa staining. Out of 230 dental plaque samples, 60 (26.08%) samples were positive for E. gingivalis, while 37 (16.08%) cases were positive for T. tenax. Diabetic patients showed high E. gingivalis percentage (n=12; 20%) (P=0.000*). However, thyroid disorders showed a low percentage. Hypertensive patients showed a high percentage for T. tenax (n=6; 16.21%) (P=0.000*), while tuberculosis patients showed the lowest percentage. Patients with hypertension, smoking, heart disease, and diabetes showed statistical significance for the presence of these parasites. Equally, patients older than 30 years have shown a higher rate of infection. According to the findings, E. gingivalis was detected in 58.33% and 41.66% of the urban and rural populations, respectively. Furthermore, T. tenax was detected in 81.08% and 18.91% of the urban and rural populations, respectively. Parasitic contagions were comparatively popular in patients with chronic and periodontal illness.


Assuntos
Placa Dentária , Entamoeba , Tricomoníase , Trichomonas , Animais , Doença Crônica , Placa Dentária/veterinária , Feminino , Masculino , Fatores de Risco , Tricomoníase/epidemiologia , Tricomoníase/parasitologia , Tricomoníase/veterinária
5.
Mol Biochem Parasitol ; 251: 111507, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35870645

RESUMO

Starvation is always accompanied by an increase in the ratio of AMP/ATP followed by activation of AMPK. It is one of the sensors for cellular energy status and is highly conserved across various species. Its role in the stage differentiation process of protozoan species like Giardia, Plasmodium, Trypanosome, and Toxoplasma has been reported. Since Entamoeba undergoes encystation in glucose-starved conditions; it intrigued us to investigate the existence and role of AMPK during the differentiation of trophozoites to the cyst. By employing in silico approaches, we have identified an AMPK homologue which is denominated here as EiAMPK (AMPK-like protein in Entamoeba invadens). Sequence and structural analysis indicate that EiAMPK is sequentially and structurally similar to the AMPK alpha subunit of other organisms. The recombinant form of EiAMPK was functionally active and in accordance, its activity was inhibited by an AMPK-specific inhibitor (eg. Compound C). The increased expression of EiAMPK during different stresses indicated that EiAMPK is a stress-responsive gene. To further investigate, whether EiAMPK has any role in encystation, we employed RNAi-mediated gene silencing that demonstrated its active involvement in encystation. It is known that Entamoeba maintains a flow of glucose from the glycolytic pathway to chitin synthesis for cyst wall formation during encystation. It is conceivable that EiAMPK might have a command over such glucose metabolism. As anticipated, the chitin synthesis was found greatly inhibited in both EiAMPK knockdown and Compound C treated cells, indicating that EiAMPK regulates the cyst wall chitin synthesis.


Assuntos
Entamoeba , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Adenilato Quinase/metabolismo , Quitina , Entamoeba/genética , Entamoeba/metabolismo , Glucose/metabolismo
6.
Folia Parasitol (Praha) ; 692022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35727049

RESUMO

Entamoeba moshkovskii Tshalaia, 1941 is prevalent in developing countries and it is considered to be primarily a free-living amoeba, which is morphologically indistinguishable, but biochemically and genetically different from the human infecting, pathogenic Entamoeba histolytica Schaudinn, 1903. The pathogenic potential of this organism is still under discussion. Entamoeba moshkovskii in human stool samples has been reported in different countries such as the United States, Italy, Australia, Iran, Turkey, Bangladesh, India (Pondicherry), Indonesia, Colombia, Malaysia, Tunisia, Tanzania and Brazil, but no data are available about the occurrence of E. moshkovskii in farm animals. This study provides data on the occurrence of E. moshkovskii in pigs in a total of 294 fresh faecal samples collected from five different regions in Kolkata, West Bengal, India. Stool samples were tested by nested PCR using primers targeting SSU rDNA of E. moshkovskii. The amplified PCR products were further confirmed by RFLP technique. Purified nested PCR products were also sequenced and identified via BLAST program run on the NCBI website to confirm species along with their genetic characteristics of the E. moshkovskii isolates. Overall 5.4 % samples were identified as E. moshkovskii positive. Results of this study demonstrate that swine can host E. moshkovskii and should be considered as a potential natural reservoir for E. moshkovskii. However, the occurrence of E. moshkovskii infection in pigs was not statistically associated with their faecal consistency, sex and developmental stage.


Assuntos
Amoeba , Entamoeba histolytica , Entamoeba , Entamebíase , Amoeba/genética , Animais , Entamoeba/genética , Entamebíase/epidemiologia , Entamebíase/veterinária , Fezes , Reação em Cadeia da Polimerase/veterinária , Suínos
7.
Front Cell Infect Microbiol ; 12: 883031, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755840

RESUMO

Australian wild deer populations have significantly expanded in size and distribution in recent decades. Due to their role in pathogen transmission, these deer populations pose a biosecurity risk to the livestock industry. However, little is known about the infection status of wild deer in Australia. The intestinal parasite Entamoeba bovis has been previously detected in farm and wild ruminants worldwide, but its epidemiology and distribution in wild ruminants remain largely unexplored. To investigate this knowledge gap, faecal samples of wild deer and domestic cattle from south-eastern Australia were collected and analysed for the presence of Entamoeba spp. using PCR and phylogenetic analysis of the conserved 18S rRNA gene. E. bovis parasites were detected at high prevalence in cattle and wild deer hosts, and two distinct Entamoeba ribosomal lineages (RLs), RL1 and RL8, were identified in wild deer. Phylogenetic analysis further revealed the existance of a novel Entamoeba species in sambar deer and a novel Entamoeba RL in fallow deer. While we anticipated cross-species transmission of E. bovis between wild deer and cattle, the data generated in this study demonstrated transmission is yet to occur in Australia. Overall, this study has identified novel variants of Entamoeba and constitutes the first report of Entamoeba in fallow deer and sambar deer, expanding the host range of this parasite. Epidemiological investigations and continued surveillance of Entamoeba parasites in farm ruminants and wild animals will be required to evaluate pathogen emergence and transmission to livestock.


Assuntos
Cervos , Entamoeba , Parasitos , Animais , Animais Selvagens , Austrália/epidemiologia , Bovinos , Cervos/parasitologia , Entamoeba/genética , Gado , Filogenia , Ruminantes
8.
Acta Parasitol ; 67(3): 1186-1198, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35587306

RESUMO

INTRODUCTION: The lobster cockroach Nauphoeta cinerea (N. cinerea) is indicated as a promising non-mammalian model, because it presents behavioral and biochemical alterations also observed in conventional models. In this research, we identified and characterized the distribution of protozoa that inhabit the digestive system (DS) of N. cinerea cockroaches. METHODS: The adult specimens of N. cinerea used in this study (n = 32) were obtained at the Federal University of Santa Maria, dissected and had their visceral contents observed in bright-field microscopy without staining and after application of lugol, Ziehl-Neelsen staining, EA36 trichrome and simulated dark-field microscopy with application of nankin ink. The presence of protozoa in different portions of the DS was semi-quantified by a system of crosses (+). RESULTS: The main taxa observed were: amoebas (Archaemebae:Entamoebida), gregarins (Apicomplexa:Eugregarinide), coccidia (Apicomplexa:Eucoccidiorida), kinetoplastids (Kinetoplastea:Kinetoplastida) and oxymonads (Preaxostyla:Oxymonadida). The highest prevalence of amoebas and gregarines was observed in the medial portion of the DS, while for the other groups, this was seen in the final portion, and in the case of coccidia, such prevalence was specially evidenced by the alcohol-acid coloration. In the present work, the great biological diversity that exists in the microbiota of the digestive system of Nauphoeta cinerea was demonstrated, being possible to find several pathogenic species for humans such as Entamoeba histolytica/dispar/moshkovskii, Cryptosporidium sp. and Cyclospora cayetanensis. There is still a lot to know about the interactions between endocommensal protozoa and their respective invertebrate hosts, so the best way to clarify such relationships is through molecular and genetic test.


Assuntos
Baratas , Criptosporidiose , Cryptosporidium , Entamoeba , Microbiota , Adulto , Animais , Sistema Digestório , Humanos , Insetos , Nephropidae
9.
mSphere ; 7(3): e0013122, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35638357

RESUMO

Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. This pathogen possesses a two-stage life cycle consisting of an environmentally stable cyst and a pathogenic amoeboid trophozoite. Since infection is acquired by ingestion of cysts from contaminated food and water, this parasite is prevalent in underdeveloped countries. A reptilian pathogen, Entamoeba invadens, which can encyst in culture, has long served as a surrogate to study stage conversion. In the host, Entamoeba species must manage stress, including nutrient deprivation and host immune pressure. In many systems, the stress response is characterized by downregulation of translation, which is initiated by the phosphorylation of eukaryotic initiation factor-2 alpha (eIF2α). In mammalian cells, this phosphorylation is carried out by a family of eIF2α kinases. A canonical eIF2α translational control system exists in Entamoeba species; however, no eIF2α kinases have been characterized. In this study, we identified two eIF2α kinases in E. invadens, EiIF2K-A and EiIF2K-B. Their identity as eIF2α kinases was validated using a heterologous yeast system. We used an RNA interference (RNAi) trigger-mediated silencing system to reduce expression of EiIF2K-A, which also reduced expression of EiIF2K-B. Parasites with decreased kinase expression exhibited decreased phosphorylation of eIF2α and increased sensitivity to oxidative stress. Diminished kinase expression also correlated with an increased rate of encystation, a decreased rate of excystation, and an increase in several virulence functions, erythrophagocytosis and adhesion to host cells. Taken together, these data suggest that EiIF2K-A and EiIF2K-B are authentic eIF2α kinases that may regulate the Entamoeba stress response. IMPORTANCE Entamoeba histolytica is a human pathogen that causes dysentery and affects millions of people worldwide. This parasite possesses a two-stage life cycle: an environmentally stable cyst and the pathogenic trophozoite. Cysts are ingested from contaminated food and water; thus, this parasite in prevalent in underdeveloped countries. Current therapies commonly cause adverse side effects; therefore, new treatments are needed. In the host, Entamoeba experiences stress brought on, in part, by the host immune system. Understanding stage conversion and the stress response of this pathogen may lead to new drug therapies. Using the model organism E. invadens, we identified two kinases similar to those involved in stress and stage conversion in other systems. We determined that these kinases may regulate the oxidative stress response, stage conversion, and virulence. This work is significant, as it will inform future studies on the life cycle and pathogenicity of Entamoeba species.


Assuntos
Cistos , Entamoeba histolytica , Entamoeba , Animais , Entamoeba/genética , Entamoeba histolytica/genética , Humanos , Estágios do Ciclo de Vida , Mamíferos , Virulência , Água , eIF-2 Quinase
10.
mBio ; 13(2): e0384921, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35404118

RESUMO

Interorganellar cross talk is often mediated by membrane contact sites (MCSs), which are zones where participating membranes come within 30 nm of one another. MCSs have been found in organelles, including the endoplasmic reticulum, Golgi bodies, endosomes, and mitochondria. Despite its seeming ubiquity, reports of MCS involving mitochondrion-related organelles (MROs) present in a few anaerobic parasitic protozoa remain lacking. Entamoeba histolytica, the etiological agent of amoebiasis, possesses an MRO called the mitosome. We previously discovered several Entamoeba-specific transmembrane mitosomal proteins (ETMPs) from in silico and cell-biological analyses. One of them, ETMP1 (EHI_175060), was predicted to have one transmembrane domain and two coiled-coil regions and was demonstrated to be mitosome membrane integrated based on carbonate fractionation and immunoelectron microscopy (IEM) data. Immunoprecipitation analysis detected a candidate interacting partner, EH domain-containing protein (EHD1; EHI_105270). We expressed hemagglutinin (HA)-tagged EHD1 in E. histolytica, and subsequent immunofluorescence and IEM data indicated an unprecedented MCS between the mitosome and the endosome. Live imaging of a green fluorescent protein (GFP)-EHD1-expressing strain demonstrated that EHD1 is involved in early endosome formation and is observed in MCS between endosomes of various sizes. In vitro assays using recombinant His-EHD1 demonstrated ATPase activity. MCSs are involved in lipid transfer, ion homeostasis, and organelle dynamics. The serendipitous discovery of the ETMP1-interacting partner EHD1 led to the observation of the mitosome-endosome contact site in E. histolytica. It opened a new view of how the relic mitochondria of Entamoeba may likewise be involved in organelle cross talk, a conserved feature of mitochondria and other organelles in general. IMPORTANCE Membrane contact sites (MCSs) are key regulators of interorganellar communication and have been widely demonstrated between various organelles. However, studies on MCSs involving mitochondrion-related organelles (MROs), present in some anaerobic parasitic protozoans, remain scarce. Entamoeba histolytica, the etiological agent of amoebiasis, possesses an MRO called the mitosome. This organelle is crucial for cellular differentiation and disease transmission, thereby significantly contributing to the amoeba's parasitic lifestyle. Our recent discovery of the interaction between the Entamoeba-specific transmembrane mitosomal protein (ETMP1) and EH domain-containing protein (EHD1) showcases a newly found mitosome-endosome contact site in E. histolytica. This finding reflects the idea that despite their substantially divergent and reduced nature, MROs like mitosomes conserve mechanisms for interorganellar cross talk. We posit lipid and ion transport, mitosome fission, and quality control as potential processes that are mediated by the ETMP1-EHD1-tethered mitosome-endosome contact site in E. histolytica.


Assuntos
Amebíase , Entamoeba histolytica , Entamoeba , Endossomos/metabolismo , Entamoeba histolytica/genética , Entamoeba histolytica/metabolismo , Humanos , Lipídeos , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte Vesicular/metabolismo
11.
Vet Clin Pathol ; 51(2): 269-272, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35274349

RESUMO

A 13-year-old 4.6 kg castrated male Italian Greyhound was presented for evaluation of sneezing, bilateral epistaxis and mucoid nasal discharge of approximately 3 months duration. Severe periodontal disease was noted on physical exam. The patient's CBC was unremarkable. His biochemical profile revealed mild azotemia as well as mild electrolyte abnormalities. Rhinoscopy revealed a tan plaque present in the left dorsal meatus of the nasal cavity. Vigorous flushing yielded granular white particulates suspended in the saline, which were cytologically examined. Marked neutrophilic inflammation, a diverse bacterial population, and organisms consistent with amoebic trophozoites were identified. The remaining fluid was analyzed by PCR and sequencing, and Entamoeba gingivalis was identified. The dog's clinical signs improved dramatically after initiating treatment with clindamycin. Six weeks after diagnosis, a dental cleaning with multiple extractions was performed. Four weeks after the dental procedure, the dog was clinically normal. This report describes the clinical, hematologic, cytologic, and gross findings in a case of Entamoeba gingivalis infection in a dog.


Assuntos
Doenças do Cão , Entamoeba , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Cães , Inflamação/veterinária , Itália , Masculino , Cavidade Nasal
12.
PLoS Negl Trop Dis ; 16(2): e0009971, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35148325

RESUMO

INTRODUCTION: Parasitic infections, especially intestinal protozoan parasites (IPPs) remain a significant public health issue in Africa, where many conditions favour the transmission and children are the primary victims. This systematic review and meta-analysis was carried out with the objective of assessing the prevalence of IPPs among school children in Africa. METHODS: Relevant studies published between January 2000 and December 2020 were identified by systematic online search on PubMed, Web of Science, Embase and Scopus databases without language restriction. Pooled prevalence was estimated using a random-effects model. Heterogeneity of studies were assessed using Cochrane Q test and I2 test, while publication bias was evaluated using Egger's test. RESULTS: Of the 1,645 articles identified through our searches, 46 cross-sectional studies matched our inclusion criteria, reported data from 29,968 school children of Africa. The pooled prevalence of intestinal protozoan parasites amongst African school children was 25.8% (95% CI: 21.2%-30.3%) with E. histolytica/ dispar (13.3%; 95% CI: 10.9%-15.9%) and Giardia spp. (12%; 95% CI: 9.8%-14.3%) were the most predominant pathogenic parasites amongst the study participants. While E. coli was the most common non-pathogenic protozoa (17.1%; 95% CI: 10.9%-23.2%). CONCLUSIONS: This study revealed a relatively high prevalence of IPPs in school children, especially in northern and western Africa. Thus, poverty reduction, improvement of sanitation and hygiene and attention to preventive control measures will be the key to reducing protozoan parasite transmission.


Assuntos
Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Parasitos/isolamento & purificação , Estudantes/estatística & dados numéricos , Adolescente , África/epidemiologia , Animais , Criança , Estudos Transversais , Cryptosporidium/classificação , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Entamoeba/classificação , Entamoeba/genética , Entamoeba/isolamento & purificação , Feminino , Giardia/classificação , Giardia/genética , Giardia/isolamento & purificação , Humanos , Higiene , Masculino , Parasitos/classificação , Parasitos/genética
13.
Bol Med Hosp Infant Mex ; 79(1): 3-16, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35086128

RESUMO

Amoebiasis is an intestinal parasitosis caused by the protozoan Entamoeba histolytica that represents the third leading cause of mortality due to parasitosis. It is a prevalent disease in tropical climate regions with poor or absent sanitary services. Microscopy and antigen detection techniques are routinely used to diagnose amoebiasis because of their low cost and ease of application. However, these techniques do not differentiate E. histolytica infections and other potentially pathogenic species such as Entamoeba moshkovskii or Entamoeba bangladeshi. Therefore, in the last decades, molecular tests that allow correct identification of the causal agent of amoebiasis and the establishment of the prevalence of the infecting species have been developed. Techniques based on nucleic acids, such as conventional, multiplex, or real-time polymerase chain reaction (PCR), are being seriously considered in clinical laboratories, because they detect the etiologic agent directly from the sample without the need for previous prolonged culture, thus reducing diagnostic time. Also, the nested PCR test and the sequencing of ribosomal markers have allowed the identification of new parasitic species in humans, such as E. moshkovskii and E. bangladeshi, and an improved characterization of the known infecting species. The application of multiplex platforms allows the simultaneous identification of infecting species, increasing the sensitivity and specificity of these techniques. Therefore, the molecular diagnosis of amoebiasis is projected as an innovative tool in the fight against this parasitosis.


La amebiasis es una parasitosis intestinal causada por el protozoario Entamoeba histolytica y representa la tercera causa de mortalidad por parasitosis. Es una enfermedad prevalente en regiones de clima tropical con deficientes o nulos servicios sanitarios. Las técnicas de microscopía y detección de antígenos se emplean sistemáticamente para el diagnóstico de la amebiasis por su bajo costo y fácil aplicación. Sin embargo, no permiten diferenciar entre infecciones por E. histolytica y otras especies de potencial patogenicidad como Entamoeba moshkovskii o Entamoeba bangladeshi. Ante ello, en las últimas décadas se han desarrollado pruebas moleculares que permiten una correcta identificación del agente causal de la amebiasis y el establecimiento de la prevalencia de la especie infectante. Las técnicas basadas en ácidos nucleicos, como la reacción en cadena de la polimerasa (PCR) convencional, múltiple o en tiempo real, están siendo seriamente consideradas en los laboratorios clínicos, porque detectan al agente etiológico de manera directa en la muestra sin necesidad de cultivo prolongado previo, disminuyendo de esta forma el tiempo del diagnóstico. Asimismo, la PCR anidada sumada a la secuenciación de marcadores ribosomales ha permitido la identificación de nuevas especies parasitarias, como E. moshkovskii y E. bangladeshi en humanos, y una mejor caracterización de las especies infectantes ya conocidas. La aplicación de las plataformas multiplex permite la identificación simultánea de especies infectantes, aumentando la sensibilidad y la especificidad de estas técnicas. Por esto, el diagnóstico molecular de la amebiasis se proyecta como una verdadera herramienta innovadora en la lucha contra las parasitosis.


Assuntos
Amebíase , Entamoeba histolytica , Entamoeba , Entamebíase , Entamoeba histolytica/genética , Entamebíase/diagnóstico , Entamebíase/epidemiologia , Entamebíase/parasitologia , Fezes/parasitologia , Humanos
14.
J Hepatol ; 76(1): 160-173, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599999

RESUMO

BACKGROUND & AIMS: An invasive form of intestinal Entamoeba (E.) histolytica infection, which causes amoebic liver abscess, is more common in men than in women. Immunopathological mechanisms are responsible for the more severe outcome in males. Here, we used a mouse model of hepatic amoebiasis to investigate the contribution of hepatic hypoxia-inducible factor (HIF)-1α to T helper 17 (Th17)/regulatory T cell (Treg) responses in the context of the sex-specific outcome of liver damage. METHODS: C57BL/6J mice were infected intrahepatically with E. histolytica trophozoites. HIF-1α expression was determined by qPCR, flow cytometry and immunohistochemistry. Tregs and Th17 cells were analysed by immunohistochemistry and flow cytometry. Finally, male and female hepatocyte-specific Hif1α knockout mice were generated, and the effect of HIF-1α on abscess development, the cytokine milieu, and Th17/Treg differentiation was examined. RESULTS: E. histolytica infection increased hepatic HIF-1α levels, along with the elevated frequencies of hepatic Th17 and Treg cells. While the Th17 cell population was larger in male mice, Tregs characterised by increased expression of Foxp3 in female mice. Male mice displayed increased IL-6 expression, contributing to immunopathology; this increase in IL-6 expression declined upon deletion of hepatic HIF-1α. In both sexes, hepatic deletion of HIF-1α reduced the Th17 cell frequency; however, the percentage of Tregs was reduced in female mice only. CONCLUSIONS: Hepatic HIF-1α modulates the sex-specific outcome of murine E. histolytica infection. Our results suggest that in male mice, Th17 cells can be modulated by hepatic HIF-1α via IL-6, indicating marked involvement in the immunopathology underlying abscess development. Strong expression of Foxp3 by hepatic Tregs from female mice suggests a potent immunosuppressive function, leading to initiation of liver regeneration. LAY SUMMARY: Infection with the parasite Entamoeba histolytica activates immunopathological mechanisms in male mice, which lead to liver abscesses that are larger than those in female mice. In the absence of the protein HIF-1α in hepatocytes, abscess formation is reduced; moreover, the sex difference in abscess size is abolished. These results suggest that HIF-1α modulates the immune response involved in the induction of immunopathology, resulting in differential disease susceptibility in males and females.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/farmacologia , Abscesso Hepático Amebiano/genética , Células Th17/metabolismo , Animais , Modelos Animais de Doenças , Entamoeba/efeitos dos fármacos , Entamoeba/patogenicidade , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Abscesso Hepático Amebiano/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Células Th17/microbiologia
15.
Pediatr Clin North Am ; 69(1): 79-97, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34794678

RESUMO

Although rare in the developed world, amebiasis continues to be a leading cause of diarrhea and illness in developing nations with crowding, poor sanitation, and lack of clean water supply. Recent immigrants or travelers returning from endemic regions after a prolonged stay are at high risk of developing amebiasis. A high index of suspicion for amebiasis should be maintained for other high-risk groups like men having sex with men, people with AIDS/HIV, immunocompromised hosts, residents of mental health facility or group homes. Clinical presentation of intestinal amebiasis varies from diarrhea to colitis and dysentery. Amebic liver abscess (ALA) is the most common form of extraintestinal amebiasis. Various diagnostic tools are available and when amebiasis is suspected, a combination of stool tests and serology should be sent to maximize the yield of testing. Treatment with an amebicidal drug such as metronidazole/tinidazole and a luminal cysticidal agent such as paromomycin for clinical disease is indicated. However, for asymptomatic disease treatment with a luminal cysticidal agent to decrease chances of invasive disease and transmission is recommended.


Assuntos
Amebíase/tratamento farmacológico , Amebíase/epidemiologia , Abscesso Hepático Amebiano/tratamento farmacológico , Abscesso Hepático Amebiano/epidemiologia , Amebíase/diagnóstico , Amebíase/transmissão , Antiprotozoários/uso terapêutico , Criança , Pré-Escolar , Colite/parasitologia , Diarreia/parasitologia , Água Potável/parasitologia , Disenteria Amebiana/epidemiologia , Entamoeba/isolamento & purificação , Fezes/parasitologia , Feminino , Humanos , Abscesso Hepático Amebiano/diagnóstico , Abscesso Hepático Amebiano/transmissão , Masculino , Metronidazol/uso terapêutico , Paromomicina/uso terapêutico , Viagem
16.
Vet Med Sci ; 8(2): 799-807, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34919350

RESUMO

BACKGROUND: The Asiatic wild water buffalo (Bubalus arnee) is an endangered species that is conserved in the Koshi Tappu Wildlife Reserve (KTWR), Nepal, and was recently translocated to the Chitwan National Park (CNP). Gastrointestinal (GI) parasites are the cause of significant negative health and production impacts on animals worldwide. METHODS: A coprological survey of GI parasites of wild water buffalo was carried out in the CNP in 2020. Fresh dung samples (n = 25) were collected from wild water buffaloes and analysed using sedimentation and flotation techniques for morphological identification of parasite cysts, oocysts and eggs. RESULTS: Nine different GI parasites were recorded of which Entamoeba spp. (20 samples, 80%) were the most common. The presence of Entamoeba spp. was further validated using polymerase chain reaction (PCR) analysis and DNA sequencing. The PCR results were positive for all of the microscopically positive samples, and the species was identified as Entamoeba bovis. Three samples were sequenced and formed a cluster of E. bovis, which was separated from other Entamoeba spp. in phylogenetic analysis. CONCLUSION: This is the first report for molecular detection of E. bovis from wild water buffaloes in Nepal. Future work should focus on the prevalence of such infections in water buffaloes in forest environments.


Assuntos
Entamoeba , Enteropatias Parasitárias , Animais , Búfalos , Entamoeba/genética , Enteropatias Parasitárias/veterinária , Nepal/epidemiologia , Filogenia , Reação em Cadeia da Polimerase/veterinária
17.
Braz. j. biol ; 82: e237839, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1249225

RESUMO

Abstract Agroecological production represents a new reality in vegetable farming. Thus, the study aimed to search for the presence of pesticides in agroecological samples and microbiological and parasitological contamination in Lactuca sativa L. of agroecological and conventional fairs in Alagoas. Thirty-two samples were collected, a hygienic-sanitary checklist was performed, along with coliform, Salmonella spp., Staphylococcus aureus research and Gas Chromatography with Mass Spectrometer (GC-MS) for pesticide research; using two methodologies for parasitological studies. Thirty-two samples were analyzed, with a sanitary adequacy level at 45% and 38% for fairs (agroecological and conventional) respectively, with three samples (9.4%) in total, being adequate to the microbiological pattern according to RDC no. 12/2001. Among the 23 samples which were tested positive for parasites, 69.5% originated from samples extracted at conventional fairs, and 53% of every positive samples presented Entamoeba coli as the main contaminant. All together, no traces of deltamethrin were detected, but in two of the samples a peak retention for diphenoconazole was detected. In conclusion, the fairs represent an adequate environment for human pathogens and indicators. Therefore greater hygiene training of vegetable traders and consumers in the state of Alagoas is required, especially in conventional fairs, which presented more critical microbiological and parasitological indexes comparing to fairs with agroecological products; however, the presence of difenoconazole in two samples of agricultural fairs suggests accidental contamination or indiscriminate use of this chemical in the production of Lactuca sativa, however, products with agroecological origin represents a better choice for the consumers.


Resumo A produção agroecológica representa uma nova realidade no cultivo das hortaliças. Assim, o estudo teve como objetivo verificar a presença de agrotóxicos em amostras agroecológicas e analisar a contaminação microbiológico e parasitológico em Lactuca sativa L. de feiras agroecológicas e convencionais de Alagoas. Foram coletadas 32 amostras, realizando checklist higiênico-sanitário, análises de coliformes, Salmonella spp., Staphylococcus aureus e Cromatografia Gasosa com Espectrômetro de Massas (GC-MS) para pesquisa de agrotóxicos; utilizando-se duas metodologias para estudos parasitológicos. Foram analisadas 32 amostras, com nível de adequação sanitária de 45% e 38% para feiras (agroecológicas e convencionais) respectivamente, sendo três amostras no total (9,4%) adequadas a padrão microbiológico segundo RDC n° 12//2001; Dentre as 23 amostras positivas para parasitos, 69,5% teve origem em amostras de feiras convencionais, e 53% de todas as amostras positivas apresentaram Entamoeba coli como principal contaminante, juntamente, não foi detectado traços de deltametrina, porem foi visualizado em duas amostras, pico de retenção para padrão de difenoconazol. Concluindo-se que as feiras representam um ambiente adequado para patógenos humanos e indicadores, necessitando de uma maior higienização e treinamento dos comerciantes e consumidores de hortaliças do estado de Alagoas, principalmente em feiras convencionais, que apresentaram índices microbiológicos e parasitológicos mais críticos em relação a feiras com produtos agroecológicos; mas, a presença de difenoconazole em duas amostras de feiras agroecológicas sugerem contaminação acidental ou uso indiscriminado deste químico em produção da Lactuca sativa L., todavia os produtos de origem agroecológica representam uma melhor escolha para o consumidor.


Assuntos
Humanos , Resíduos de Praguicidas/análise , Entamoeba , Verduras , Contaminação de Alimentos/análise , Alface , Agricultura
18.
Front Cell Infect Microbiol ; 11: 782805, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34950608

RESUMO

Background: The etiology of periodontitis remains unclear, as is the place of gingivitis in its pathophysiology. A few studies linked the colonization by oral parasites (Entamoeba gingivalis and Trichomonas tenax) to periodontal disease and its severity. The aim of the current study was to estimate the prevalence of these oral parasites among healthy individuals, and in patients with gingivitis and periodontitis in Jordan. Methods: The study was conducted during July 2019-December 2019. Samples were composed of saliva and periodontal material including dental plaque sampled with probes. The detection of oral parasites was done using conventional polymerase chain reaction (PCR). Results: The total number of study participants was 237: healthy (n=94), gingivitis (n=53) and periodontitis (n=90). The prevalence of E. gingivalis was 88.9% among the periodontitis patients, 84.9% among the gingivitis patients and 47.9% in the healthy group. For T. tenax, the prevalence was 25.6% among the periodontitis patients, 5.7% among the gingivitis patients and 3.2% in the heathy group. Positivity for E. gingivalis was significantly correlated with the presence of periodontal disease compared to the healthy group with odds ratio (OR) of 6.6. Periodontal disease was also correlated with lower monthly income (OR=8.2), lack of dental care (OR=4.8), and history of diabetes mellitus (OR=4.5). Colonization by E. gingivalis was correlated with gingivitis (OR=6.1) compared to the healthy group. Colonization by E. gingivalis and T. tenax were significantly correlated with periodontitis (OR=6.4 for E. gingivalis, and OR=4.7, for T. tenax) compared to the healthy group. T. tenax was only detected among individuals with generalized periodontal disease compared to its total absence among those with localized disease (19.6% vs. 0.0%; p=0.039). The co-infection rate by the two oral parasites was 11.0%. Conclusions: The higher prevalence of human oral parasites in periodontal disease compared to healthy individuals appears to be more than a mere marker for the disease and might also be associated with disease severity and potential for progression. Thus, the dogmatic view of E. gingivalis and T. tenax as commensals needs to be re-evaluated and their contribution to pathophysiology of periodontal diseases cannot be neglected.


Assuntos
Entamoeba , Gengivite , Periodontite , Tricomoníase , Trichomonas , Gengivite/epidemiologia , Humanos , Periodontite/epidemiologia , Reação em Cadeia da Polimerase , Porphyromonas gingivalis/genética , Trichomonas/genética , Tricomoníase/epidemiologia
19.
Biomed Res Int ; 2021: 5746629, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34697588

RESUMO

Entamoeba histolytica is the causative agent of amoebiasis, and Entamoeba dispar is its noninvasive morphological twin. Entamoeba invadens is a reptilian parasite. In the present study, Western blot, phosphatase activity, immunofluorescence, and bioinformatic analyses were used to identify PP2C phosphatases of E. histolytica, E. dispar, and E. invadens. PP2C was identified in trophozoites of all Entamoeba species and cysts of E. invadens. Immunoblotting using a Leishmania mexicana anti-PP2C antibody recognized a 45.2 kDa PP2C in all species. In E. histolytica and E. invadens, a high molecular weight element PP2C at 75 kDa was recognized, mainly in cysts of E. invadens. Immunofluorescence demonstrated the presence of PP2C in membrane and vesicular structures in the cytosol of all species analyzed. The ~75 kDa PP2C of Entamoeba spp. shows the conserved domain characteristic of phosphatase enzymes (according to in silico analysis). Possible PP2C participation in the encystation process was discussed.


Assuntos
Entamoeba/enzimologia , Proteína Fosfatase 2C/metabolismo , Proteínas de Protozoários/metabolismo , Trofozoítos/enzimologia , Sequência de Aminoácidos , Animais , Entamoeba/isolamento & purificação , Entamebíase/parasitologia , Entamebíase/patologia , Humanos , Filogenia , Proteína Fosfatase 2C/química , Proteína Fosfatase 2C/genética , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Homologia de Sequência de Aminoácidos , Trofozoítos/isolamento & purificação
20.
Ann Parasitol ; 67(2): 347-349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34598408

RESUMO

Children are more susceptible to intestinal parasitic diseases than adults due to their lack of hygiene habits and close social interactions with their peers. We present a case of a 5-year-old boy with diarrhea and abdominal pain. The stool sample and perianal swab were examined in LINA laboratory, Burgas, Bulgaria. We detected four parasites Giardia (Lamblia) intestinalis, Blastocystis hominis, Hymenolepis nana and Entamoeba coli. Microbiological stool examination shows negative results for Candida spp., Salmonella spp. and Shigella spp. Patient's peripheral blood tests were normal. The calprotectin in faeces was tested establishing slightly increased values. The presence of four parasites in one patient in Bulgaria (in the 21st century) is a rare case. Lambliosis and hymenolepiosis are more likely to be found in this patient's region. Following the presence of Entamoeba coli and the transmission mechanism of the other three parasites it can be concluded that the child's hygiene is poor. This patient reveals typical clinical picture with mild symptoms and normal paraclinical results. The presence of parasites in a definitive host is not necessarily related with the development of pathological departures. The fight with parasitic diseases can be successful with a broad integral approach - recognizing and diagnosing the parasites promptly and using radical and suitable treatment.


Assuntos
Entamoeba , Parasitos , Adulto , Animais , Bulgária/epidemiologia , Criança , Pré-Escolar , Fezes , Humanos , Higiene , Masculino
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