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Journal of Parasitic Diseases :... Sep 2019keratitis (AK) is a severe corneal disease that was reported by WHO as the second most common infectious cause of blindness after trachoma; contact lens wear is...
keratitis (AK) is a severe corneal disease that was reported by WHO as the second most common infectious cause of blindness after trachoma; contact lens wear is considered one of the main risk factors in its transmission. Thus, the treatment of AK is crucial but, the inability of medical agents to completely eradicate the resistant cyst, together with their toxic effects, suggest that new agents are needed. Vinegar has been known long ago as a simple and available disinfectant with antimicrobial effects, so the present study aimed to test the effect of different concentrations of vinegar solution on isolate, along the period of 1 h in comparison to parasite and chlorhexidine controls. Post hoc test analysis revealed a highly significant difference between the vinegar-treated parasites and both controls, as regards the viable and non-viable mean cysts count. Vinegar concentration of 5% exhibited the highest mean of non-viable cysts along the time intervals, while the lowest was shown with 0.04% where also, no viable cysts were detected at 60 min. All tested concentrations behaved in a time-dependent manner. There was a positive correlation with a significant outcome between the different concentrations and the mean of the non-viable parasites along time. Transmission electron microscopy of treated cysts revealed corrugated altered cell wall with loss of ridges and detachment and shrinkage of content. Treated trophozoites showed flattening of the acanthopodia with thinned out plasma membrane and degenerated cytoplasmic content. The study highlighted the potential use of vinegar as an adjuvant in the prevention and treatment of AK.
PubMed: 31406399
DOI: 10.1007/s12639-019-01098-3 -
International Journal For Parasitology Nov 1989A comparative study of membrane carbohydrate characteristics of pathogenic and non-pathogenic trophozoites and cysts of free-living Acanthamoeba castellanii, Naegleria...
A comparative study of membrane carbohydrate characteristics of pathogenic and non-pathogenic trophozoites and cysts of free-living Acanthamoeba castellanii, Naegleria fowleri and A. astronyxis, respectively from sewage sludge in India was carried out by means of fluorescein-conjugated lectin binding using eight lectins. Two lectins, viz. Concanavalin A and Phytohaemagglutinin P, could bind all free-living amoebae at different concentrations. The most notable feature of the study is that peanut agglutinin (PNA) and wheatgerm agglutinin (WGA) can differentiate between the pathogenic A. castellanii and non-pathogenic A. astronyxis strain, respectively. However, Ulex agglutinin I (UEA I) was the only lectin positive to both pathogenic A. castellanii and N. fowleri. During in vitro conversion from trophozoites to cysts, A. castellanii and N. fowleri cysts gained WGA-specific saccharide whereas A. castellanii; A. astronyxis and N. fowleri lost or reduced Dolichos biflorus agglutinin, PNA; WGA and ConA, and UEA I-specific saccharides, respectively. Neuraminidase could not alter the fluorescein-lectin binding to WGA and PNA. These demonstrated that only two lectins can recognize the factors giving Acanthamoeba their pathogenic (PNA-specific) and non-pathogenic (WGA-specific) status. More interestingly, UEA I can only differentiate between pathogenic and non-pathogenic amoebae. It is also suggested that during stage conversion the surface of the organism exhibited replacement of saccharides.
Topics: Acanthamoeba; Animals; Carbohydrates; Lectins; Microscopy, Fluorescence; Naegleria
PubMed: 2592141
DOI: 10.1016/0020-7519(89)90060-x -
The Journal of Protozoology Aug 1982The fine structure of the trophozoite, encysting cells, and the cyst of Acanthamoeba astronyxis has been examined. In the trophic form a microtubule organizing center...
The fine structure of the trophozoite, encysting cells, and the cyst of Acanthamoeba astronyxis has been examined. In the trophic form a microtubule organizing center was associated with a well developed Golgi complex. During encystment the organelles of the amoeba changed considerably. The profiles of rough endoplasmic reticulum elongated and were often arranged in circles of multilayered concentric systems, enclosing mitochondria, the nucleus, or other inclusions. The mitochondria showed a tendency toward elongation and constriction. One or two nucleolus-like bodies appeared in the nucleus. Lipid droplets increased considerably in amount and were distributed individually or as aggregates. The mature cyst was star-shaped and surrounded by an almost circular exocyst and an endocyst that was closely apposed to the cell membrane. Both walls differed in their thickness and granulation. The exocyst was continuous over the entire cyst, while the endocyst was interrupted by gaps, ostioles, in the region of the rays. Within the ostioles was a bell-shaped structure, the operculum. The latter was composed of a granular material comparable in electron density to that of the endocyst.
Topics: Amoeba; Animals; Cell Membrane; Cell Nucleus; Cytoplasm; Endoplasmic Reticulum; Golgi Apparatus; Microscopy, Electron; Mitochondria
PubMed: 7131355
DOI: 10.1111/j.1550-7408.1982.tb05433.x -
Clinical and Diagnostic Laboratory... Jul 2001Acanthamoeba species can cause serious, debilitating, and sometimes life-threatening infections. Three groups have been identified using morphological and immunological...
Acanthamoeba species can cause serious, debilitating, and sometimes life-threatening infections. Three groups have been identified using morphological and immunological comparisons. Previous serological studies have utilized a variety of antigen preparations and assay methods and reported disparate (3 to 100%) results. This study was designed to (i) optimize an enzyme-linked immunosorbent assay for detecting serum antibodies to each of the Acanthamoeba serogroups and (ii) test 55 healthy individuals for specific immunoglobulin G reactivity. The highest signal-to-background ratio was found when 3,000 fixed, intact trophozoites per well were used with a 1:10 serum dilution. Sera yielding optical densities of <0.25 against all three Acanthamoeba serogroups were used to define the cutoff for positive results. The highest background reactivity with these sera was seen with Acanthamoeba polyphaga (serogroup 2), followed by Acanthamoeba culbertsoni (serogroup 3) and Acanthamoeba astronyxis (serogroup 1). Of 55 subjects tested, the highest number of positive results was seen with A. polyphaga (81.8%), followed by A. astronyxis (52.8%) and A. culbertsoni (40%). Seven serum samples (12.7%) were negative for all three Acanthamoeba serogroups, 16 (29.1%) were positive for one serogroup only, 16 were positive for two serogroups, and 16 reacted to all three serogroups. Further analysis showed no significant associations between serogroup reactivity and age or gender. However, some ethnic differences were noted, especially with A. polyphaga antigens. In that case, serum samples from Hispanic subjects were 14.5 times less likely to be positive (P = 0.0025) and had lower mean absorbance values (P = 0.047) than those from Caucasian subjects. Overall, these data suggest that Acanthamoeba colonization or infection is more common than previously thought. Mild or asymptomatic infections may contribute to the observed serum reactivities.
Topics: Acanthamoeba; Adult; Amebiasis; Animals; Antibodies, Protozoan; Antigens, Protozoan; Enzyme-Linked Immunosorbent Assay; Female; Health Status; Humans; Male; Middle Aged; Rabbits; Reproducibility of Results
PubMed: 11427418
DOI: 10.1128/CDLI.8.4.724-730.2001 -
Parasitology Research Jun 2021Group 1 acanthamoebae are morphologically and phylogenetically distinct from all other Acanthamoeba species. They include five species, each labelled by its genotype: A....
Group 1 acanthamoebae are morphologically and phylogenetically distinct from all other Acanthamoeba species. They include five species, each labelled by its genotype: A. astronyxis (T7), A. tubiashi (T8), A. comandoni (T9), unnamed Acanthamoeba sp. (T17), and A. byersi (T18). Thought only environmental, they have recently attracted attention due to their recovery in cases of human keratitis and encephalitis, the main diseases caused by Acanthamoeba, where the usual causative agents are mainly species of Groups 2 and 3. Analysis of the available data confirms the pathogenic importance of these species, although it is probably minor compared to that of the species in Groups 2 and 3. In addition, it should be noted that there are difficulties in identifying genotypes by widely used molecular methods, and some misidentifications are revealed.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Central Nervous System Protozoal Infections; Genetic Variation; Genotype; Humans; Infectious Encephalitis; Phylogeny
PubMed: 33928443
DOI: 10.1007/s00436-021-07171-2 -
Journal of the Egyptian Society of... Apr 2017Acanthamoeba is an opportunistic pathogen cauAing keratitis and fatal encephalitis. Early diagnosis, followed by intense treatment using a drugs mixture is a necessity...
Acanthamoeba is an opportunistic pathogen cauAing keratitis and fatal encephalitis. Early diagnosis, followed by intense treatment using a drugs mixture is a necessity for effective therapy. Many natural compounds have proved lethal effects, yet the search for original natural amebicidal agents is still of current concern. This study investigated the acanthamoebicidal effect of A. hypogaea L. pericarp; total ethanol extract and its successive fractions, n-hexane, dichloro-methane, ethyl acetate, and methanol as well as resveratrol. Acanthamoebae were isolated and cultivated on E. coli seeded non-nutrient agar, genotyped, and the in vitro acanthamoebicidal potentials of different concentrations of A. hypogaea L. pericarp; total extract ethanol and its successive fractions and resveratrol compound was investgated on cysts of A. astronyxis T7 genotype. The results showed variable degrees of lethal potentials were obtained by all examined A. hypogaea L. pericarp ethanol extract and its successive fractions, with the highest mean of non-viable cysts on the first and the second days. bf the study by total ethanol extract followed by the methanol fraction . On the third day of the study n-hexane and ethyl acetate gave the highest mean of non-viable cysts. Resveratrol showed the lowest mean of non-viable cysts count all through the study duration. Significantly higher difference was observed between all examined A. hypogaea L. pericarp extract and fractions and chlorohexidine, except for resveratrol compound the difference was found to be noinsignificant.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Analysis of Variance; Antioxidants; Arachis; Cornea; Genotype; Genotyping Techniques; Phylogeny; Plant Extracts; Resveratrol; Sequence Analysis, DNA
PubMed: 30157339
DOI: No ID Found -
The Journal of Protozoology Feb 1978A new species of Acanthamoeba was isolated from a culture of an established line of human choriocarcinoma cells. The identification of this strain, originally called the...
A new species of Acanthamoeba was isolated from a culture of an established line of human choriocarcinoma cells. The identification of this strain, originally called the Oak Ridge strain, and the establishment of a new species for it were based on morphologic, serologic, and immunochemical studies. In general, the structure of the trophozoite did not differ significantly from that of other species of Acanthamoeba, except that a body which more closely resembled a centriole than material described previously as centriolar satellites was observed in trophozoites examined with the electron microscope. The dimensions of the trophozoite were the smallest among the species of Acanthamoeba. The cyst was typical of the genus, but differed from those of other species by its smaller size and the presence of numerous ostioles. Studies of the Oak Ridge strain by immunofluorescence using antisera developed against the isolate and Acanthamoeba culbertsoni, A. castellanii, A. polyphaga, A. rhysodes, A. astronyxis, and A. palestinensis revealed the antigenic uniqueness of the Oak Ridge strain. It was demonstrated by immunoelectrophoretic analyses of the soluble proteins of the Oak Ridge strain that shared approximately 1/2 of its antigenic structure with A. castellanii and A. culbertsoni. The antigenic differences of the isolate from other species of Acanthamoeba were deduced from comparison of the antigenic constitution of these species and the Oak Ridge strain with A. culbertsoni and A. castellanii. Although the strain was initially recognized by its cytopathogenicity for cultures, it did not produce acute infections in mice after intranasal inoculation of 1 X 10(4) ameba/mouse. The foregoing results constituted the basis for the establishment of the Oak Ridge strain as a new species, A. royreba sp. n., in the genus Acanthamoeba.
Topics: Amoeba; Animals; Antigens; Cell Line; Choriocarcinoma; Female; Humans; Immunoelectrophoresis; Mice; Microscopy, Electron; Pregnancy
PubMed: 566323
DOI: 10.1111/j.1550-7408.1978.tb03854.x -
The Journal of Parasitology Feb 2005Random amplified polymorphic DNA (RAPD) is a useful tool for species identification. The obtained band patterns can be used for specific primer pair design that is...
Random amplified polymorphic DNA (RAPD) is a useful tool for species identification. The obtained band patterns can be used for specific primer pair design that is useful for species identification. In this study, a distinctive 485-bp band in Acanthamoeba astronyxis band patterns was found, using the OPC20 primer (ACTTCGCCAC). The band specificity was confirmed by hybridization, using it as a probe, against all OPC20 amplifications from different Acanthamoeba species. Once the fragment was sequenced, we used it to design a specific primer pair that was useful for the identification of different isolates as A. astronyxis species.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Animals; Base Sequence; DNA Primers; DNA, Protozoan; Humans; Molecular Sequence Data; Nucleic Acid Hybridization; Polymerase Chain Reaction; Random Amplified Polymorphic DNA Technique; Reproducibility of Results; Species Specificity; Water
PubMed: 15856884
DOI: 10.1645/GE-3301 -
Infection and Immunity Apr 2003In this study we investigated the role of the bacterial flagellum in Burkholderia pseudomallei entry to Acanthamoeba astronyxis trophozoites. B. pseudomallei cells were...
In this study we investigated the role of the bacterial flagellum in Burkholderia pseudomallei entry to Acanthamoeba astronyxis trophozoites. B. pseudomallei cells were tethered to the external amoebic surface via their flagella. MM35, the flagellum-lacking fliC knockout derivative of B. pseudomallei NCTC 1026b did not demonstrate flagellum-mediated endocytosis in timed coculture, confirming that an intact flagellar apparatus assists B. pseudomallei entry into A. astronyxis.
Topics: Acanthamoeba; Animals; Bacterial Adhesion; Burkholderia pseudomallei; Coculture Techniques; Flagella; Flagellin; Microscopy, Electron; Microscopy, Electron, Scanning; Mutation
PubMed: 12654857
DOI: 10.1128/IAI.71.4.2280-2282.2003 -
Folia Parasitologica Dec 2022Species of Acanthamoeba Volkonsky, 1931 are the commonest among free-living amoebae that are widespread in different water resources but with lacking phylogenetic data....
Species of Acanthamoeba Volkonsky, 1931 are the commonest among free-living amoebae that are widespread in different water resources but with lacking phylogenetic data. This study aims at detecting molecular prevalence and genetic diversity of Acanthamoeba isolates in Kafrelsheikh Governorate, Egypt. Forty-eight water samples were collected from 12 swimming pools; four samples during each season over one year. Samples were filtered, cultivated on non-nutrient agar plates and examined microscopically. Polymerase chain reaction (PCR) and sequence analysis of positive samples targeting diagnostic fragment 3 (DF3) of the small subunit rRNA gene were done. Cultivation succeeded to detect 14 (29%) positive samples while PCR missed three positive samples. The obtained sequences were phylogenetically analysed. The phylogenetic tree was constructed for them with sequences of reference species from the NCBI database. The identified species were Acanthamoeba castellanii Douglas, 1930 (T4), A. astronyxis (Ray et Hayes, 1954) (T9) and A. hatchetti Sawyer, Visvesvara et Harke, 1977 (T11). The prevalence of species of Acanthamoeba was higher during summer and fall. Therefore, the control of the presence of Acanthmoeba spp. in swimming pools needs immediate, effective and practical measures to prevent and control infection with species of Acanthamoeba.
Topics: Acanthamoeba; Phylogeny; Egypt; Swimming Pools; Genotype
PubMed: 36534004
DOI: 10.14411/fp.2022.029