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Veterinary Parasitology Jul 2016Associations with free-living protozoa (FLP) have been implicated in the persistence of foodborne pathogenic bacteria in food-related environments. To date however no...
Associations with free-living protozoa (FLP) have been implicated in the persistence of foodborne pathogenic bacteria in food-related environments. To date however no information is available on the presence of FLP in the gastrointestinal tract (GIT) of pigs, which represents an important reservoir for zoonotic foodborne bacteria and hence a potential location for associations with FLP. This is at least partly due to the lack of adequate protocols to recover FLP from intestinal content and feces. In the present study different protocols to recover FLP from the porcine GIT and feces were tested. The most effective protocols were then applied to explore the presence of live FLP in the pig GIT and feces. A filtration based protocol was identified as the most suitable method to recover viable FLP from the porcine GIT and feces. Cultivable FLP were recovered from different parts of the GIT, suggesting at least a transient presence of FLP in this habitat. Free-living amoebae species (Acanthamoeba spp., Hyperamoeba sp., Vannella sp., Vermamoeba vermiformis, hartmannellids and vahlkampfiids) but also ciliates (Colpoda sp. and Tetrahymena/Glaucoma lookalike) and flagellates (cercomonads, bodonids and glissomonads) were recovered and cultured from pig intestinal content. Acanthamoeba hatchetti and Filamoeba sinensis were isolated for the first time from pig intestinal content. Despite high gastric acidity, non-cyst forming amoeba species were also detected which suggests survival of their trophozoites in the animal GIT.
Topics: Amoeba; Animals; Biodiversity; Ciliophora; Feces; Gastrointestinal Tract; Swine; Trophozoites
PubMed: 27369581
DOI: 10.1016/j.vetpar.2016.06.002 -
European Journal of Protistology Oct 2016Acanthamoebae feed on bacteria but are also frequent hosts of bacterial symbionts. Here, we describe the stable co-occurrence of two symbionts, one affiliated to the...
Acanthamoebae feed on bacteria but are also frequent hosts of bacterial symbionts. Here, we describe the stable co-occurrence of two symbionts, one affiliated to the genus Parachlamydia and the other to the candidate genus Paracaedibacter (Alphaproteobacteria), within a clinical isolate of Acanthamoeba hatchetti genotype T4. We performed fluorescence in situ hybridization (FISH) and transmission electron microscopy (TEM) to describe this symbiosis. Our study adds to other reports of simultaneous co-occurrence of two symbionts within one Acanthamoeba cell.
Topics: Acanthamoeba; Alphaproteobacteria; Amebiasis; Chlamydiales; Humans; In Situ Hybridization, Fluorescence; Keratitis; Microscopy, Electron, Transmission; Phylogeny; RNA, Ribosomal, 16S; Symbiosis
PubMed: 27344110
DOI: 10.1016/j.ejop.2016.04.002 -
Parasites & Vectors Mar 2016Acanthamoeba is an emerging potentially pathogenic amoeba that has been receiving increasing attention worldwide as a reservoir and potential vector for the transmission...
BACKGROUND
Acanthamoeba is an emerging potentially pathogenic amoeba that has been receiving increasing attention worldwide as a reservoir and potential vector for the transmission of pathogenic bacteria. It is also associated with brain cell damage, keratitis and skin irritation in humans. Its effects are more severe in immunocompromised individuals. This study provides for the first time in Uganda, information on the prevalence and genotypes of Acanthamoeba in environmental and domestic (tap) water.
METHODS
A total of 324 environmental and 84 tap water samples were collected between November 2013 and September 2014. The samples were centrifuged, cultured (Non-Nutrient agar seeded with gram-negative bacteria) and observed under a microscope. After confirmation of Acanthamoeba, genomic DNA was extracted for PCR assays by chemical lysis and purification with phenol/chloroform/isoamyl alcohol. Samples that showed the strongest positive bands (400-600 bp) were subjected to cycle sequencing.
RESULTS
Among environmental and tap water samples, 107 (33 %) and 36 (42.9 %) tested positive for Acanthamoeba spp., respectively. Prevalence of Acanthamoeba from specific environmental locations was as follows; Kazinga channel banks (60.7 %), Fish landing sites (50 %), River Kyambura (39.6 %) and Kazinga mid channel (5.3 %). There was a significant difference (p = 0.001) in the prevalence of Acanthamoeba between sampling sites. The mean (Mean ± SE) occurrence of the organism was higher in Kazinga channel banks (3.44 ± 0.49) and Fish landing sites (3.08 ± 0.53). Correlation between in situ parameters and Acanthamoeba was insignificant except for the Dissolved Oxygen (mg/ML) which was negatively correlated (r = -0.231, p = 0.001) to Acanthamoeba. Six distinct partial Acanthamoeba T-genotype groups T1, T2, T4, T5, T6 and T11 were obtained. Ultimately, Acanthamoeba spp., Acanthamoeba hatchetti and Acanthamoeba polyphaga were isolated in the current study.
CONCLUSIONS
There was a high prevalence of Acanthamoeba in communal piped tap and environmental water used by communities, indicating poor environmental and domestic water quality.
Topics: Acanthamoeba; DNA, Protozoan; Genetic Variation; Genotype; Microscopy; Polymerase Chain Reaction; Prevalence; Sequence Analysis, DNA; Uganda; Water
PubMed: 26935431
DOI: 10.1186/s13071-016-1411-y -
Journal of Water and Health Sep 2015Free living amoebae (FLA) are amphizoic protozoa that are ubiquitous in nature. Infection with FLA may result in neurological, ocular and skin infections. Exposure to...
Free living amoebae (FLA) are amphizoic protozoa that are ubiquitous in nature. Infection with FLA may result in neurological, ocular and skin infections. Exposure to Acanthamoeba occurs frequently through water contact and knowledge of the presence of the organisms in water sources is important in understanding transmission dynamics. The distribution of Acanthamoeba was studied in recreational and domestic water samples collected from across Jamaica. Morphological assessment and polymerase chain reaction revealed Acanthamoeba spp. isolates in 50.6% (42/83) and 17.3% (14/81) of recreational and domestic water, respectively. Sequencing of the DF3 region of the 18S rDNA resulted in the identification of genotypes T3, T4, T5, T10 and T11 corresponding to Acanthamoeba spp: A. griffini, A. triangularis, A. lenticulata, A. culbertsoni and A. hatchetti. Moreover, T4 was the most frequently isolated genotype in both recreational and domestic water. Thermotolerance and osmotolerance assays indicated that most isolates were potentially pathogenic. This is the first report of T3 and T10 genotypes in the Caribbean and the first report of these Acanthamoeba spp. in Jamaican waters. The study shows that there is potential risk of infection to contact wearers who practise poor lens care. Further, Acanthamoeba should be considered as a cause of neurological infections in Jamaica.
Topics: Acanthamoeba; Bathing Beaches; Contact Lenses; Fresh Water; Genotype; Humans; Jamaica; Natural Springs; Risk Assessment; Seawater
PubMed: 26322776
DOI: 10.2166/wh.2015.232 -
Journal of Clinical Microbiology Aug 2014A case of amoebic placentitis in a mare from eastern Australia was diagnosed postpartum by histopathological examination of the placenta. The identity of the etiological...
A case of amoebic placentitis in a mare from eastern Australia was diagnosed postpartum by histopathological examination of the placenta. The identity of the etiological agent was confirmed as Acanthamoeba hatchetti by use of diversity profiling based on a next-generation sequencing approach.
Topics: Acanthamoeba; Amebiasis; Animals; Australia; DNA, Protozoan; Female; High-Throughput Nucleotide Sequencing; Horse Diseases; Horses; Molecular Sequence Data; Placenta Diseases; Pregnancy; Pregnancy Complications, Parasitic
PubMed: 24829227
DOI: 10.1128/JCM.01071-14 -
BioMed Research International 2013This study evaluated the presence of Acanthamoeba species in the Puzih River watershed, which features typical subtropical monsoon climate and is located just above the...
This study evaluated the presence of Acanthamoeba species in the Puzih River watershed, which features typical subtropical monsoon climate and is located just above the Tropic of Cancer in Taiwan. The relationship between the seasonal and geographical distributions of Acanthamoeba species in this rivershed was also investigated. Acanthamoeba species were detected in water samples using the amoebal enrichment culture method and confirmed by PCR. A total of 136 water samples were included in this study, 16 (11.7%) of which contained Acanthamoeba species. Samples with the highest percentage of Acanthamoeba (32.4%) were obtained during the summer season, mainly from upstream areas. The identified species in the four seasons included Acanthamoeba palestinensis (T2), Acanthamoeba sp. IS2/T4 (T4), Acanthamoeba lenticulata (T5), Acanthamoeba hatchetti (T11), Acanthamoeba healyi (T12), and Acanthamoeba jacobsi (T15). The most frequently identified Acanthamoeba genotype was T4 (68.7%). Acanthamoeba genotype T4 is responsible for Acanthamoeba keratitis and should be considered for associated human health risk potential in the rivershed.
Topics: Acanthamoeba; Genetic Variation; Genotype; Humans; Phylogeny; Seasons; Sequence Analysis, DNA; Taiwan
PubMed: 24490160
DOI: 10.1155/2013/405794 -
Acta Tropica Apr 2014The occurrence of Acanthamoeba was investigated from 21 main reservoirs of Taiwan with 12 (57.1%) testing positive. Analysis of the 18S rRNA gene PCR product was...
The occurrence of Acanthamoeba was investigated from 21 main reservoirs of Taiwan with 12 (57.1%) testing positive. Analysis of the 18S rRNA gene PCR product was performed in order to identify the Acanthamoeba isolates. Acanthamoeba spp. concentrations were determined according to TaqMan real-time qPCR. Acanthamoeba genotypes of all isolates were identified T4. The species were categorized to Acanthamoeba culbertsoni, Acanthamoeba polyphaga, Acanthamoeba castellanii and Acanthamoeba hatchetti. The concentration of Acanthamoeba spp. in detected positive reservoir water samples was in the range of 3.0-1.8 × 10(3) cells/L. These results highlight the importance of Acanthamoeba in reservoirs of potential pathogens and its possible role in the spread of bacterial genera with interest in public and environmental health.
Topics: Acanthamoeba castellanii; DNA, Protozoan; Genotype; Humans; Molecular Sequence Data; RNA, Ribosomal, 18S; Real-Time Polymerase Chain Reaction; Sequence Analysis, DNA; Taiwan; Water
PubMed: 24388954
DOI: 10.1016/j.actatropica.2013.12.020 -
Investigative Ophthalmology & Visual... Jul 2013To investigate experimental variables in the development of standardized methods to assess the efficacy of contact lens disinfection systems against the trophozoite and...
PURPOSE
To investigate experimental variables in the development of standardized methods to assess the efficacy of contact lens disinfection systems against the trophozoite and cysts of Acanthamoeba spp.
METHODS
A. castellanii (ATCC 50370), A. polyphaga (ATCC 30461), and A. hatchetti (CDC: V573) were adapted to axenic culture and used to produce cysts either with Neff's encystment medium (NEM) or starvation on nonnutrient agar (NNA). Challenge test assays and a most probable number approach were used to compare the trophozoite and cysticidal efficacy of four multipurpose disinfectant solutions (MPDSs) and a one-step hydrogen peroxide system (with and without the neutralizing step).
RESULTS
With trophozoites, four of four MPDSs and the one-step peroxide system gave ≥3 log₁₀ kill for all strains 6 hours, regardless of culture medium used. Greater resistance was found against cysts, with results for MPDSs varying by species and method of cyst production. Here, 1-3 log₁₀ kill was found with NEM cysts for three of four MPDSs compared with one of four for the NNA cysts at 6 hours (A. castellanii and A. polyphaga, only). The one-step peroxide system gave 1-1.9 log₁₀ kill with NEM cysts and 0.8-1.1 for NNA cysts. Only 3% hydrogen peroxide gave total kill (>3 log₁₀) of NNA cysts at 6 hours.
CONCLUSIONS
A reproducible method for determining the susceptibility of Acanthamoeba trophozoites and cysts to contact lens care systems has been developed. This will facilitate assay standardization for assessing the efficacy of such products against the organism and aid development of improved disinfectant and therapeutic agents.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Amebiasis; Amebicides; Animals; Contact Lens Solutions; Cysts; Disinfectants; Disinfection; Hydrogen Peroxide; Parasitic Sensitivity Tests; Reference Standards; Trophozoites
PubMed: 23745008
DOI: 10.1167/iovs.13-11927 -
Clinical & Experimental Ophthalmology Mar 2014In this study, a series of compounds - miltefosine, polyhexamethylene biguanide, chlorhexidine and propamidine isethionate - and combinations of the latter three agents... (Comparative Study)
Comparative Study
BACKGROUND
In this study, a series of compounds - miltefosine, polyhexamethylene biguanide, chlorhexidine and propamidine isethionate - and combinations of the latter three agents with miltefosine were prepared and used in a rat model for the topical treatment of Acanthamoeba keratitis.
METHODS
The corneas of rats were infected with Acanthamoeba hatchetti. On the fifth day, all corneas were microscopically examined in order to determine the grade of infections. Nine groups were then prepared: miltefosine (65.12 μg/mL); chlorhexidine (0.02%); polyhexamethylene biguanide (0.02%), propamidine isethionate (0.1%), miltefosine plus chlorhexidine, miltefosine plus polyhexamethylene biguanide; miltefosine plus propamidine isethionate; infected control; and a non-infected control group. The treatment was continued for 28 days. After the treatment, the corneas were excised and used for Acanthamoeba culture to investigate the presence of Acanthamoeba growth. For the determination of cytotoxicity of the drugs on L929 cells, colorimetric assays were performed.
RESULTS
The best treatment results were obtained from the polyhexamethylene biguanide plus miltefosine group; the ratio of fully recovered eyes was 28.4%. It was proven that the miltefosine-polyhexamethylene biguanide combination yielded the highest anti-acanthamoebal activity in that approximately 86% of the eyes were cleared from amoebae. The cytotoxicity values of the miltefosine and the control groups were compared with other groups and found to be statistically different (P < 0.05).
CONCLUSION
This in vivo study demonstrates that a miltefosine-polyhexamethylene biguanide combination is highly effective for the treatment of Acanthamoeba keratitis.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Animals; Antiprotozoal Agents; Biguanides; Cell Line; Cell Proliferation; Disease Models, Animal; Disinfectants; Drug Therapy, Combination; Fibroblasts; Male; Phosphorylcholine; Rats; Rats, Wistar
PubMed: 23601234
DOI: 10.1111/ceo.12120 -
Parasitology Research Feb 2013Acanthamoeba keratitis (AK) is a potentially devastating and sight-threatening infection of the cornea caused by the ubiquitous free-living amoebae, Acanthamoeba...
Acanthamoeba keratitis (AK) is a potentially devastating and sight-threatening infection of the cornea caused by the ubiquitous free-living amoebae, Acanthamoeba species. Its eradication is difficult because the amoebas encyst, making it highly resistant to anti-amoebic drugs. Acriflavine neutral (ACF) has been used for treatment of microbial infections for humans and fishes. The aim of our study was to evaluate the time-dependent cytotoxicities of ACF against Acanthamoeba spp. Trophozoites and cysts of three different strains (strain PAT06 Acanthamoeba castellanii, strain 2HH Acanthamoeba hatchetti, and strain 11DS A. hatchetti) of Acanthamoeba spp. were tested. All strains had been isolated from patients suffering from a severe AK. The effects of the ACF with the concentrations ranging from 15 to 500 mg mL(-1) on the cytotoxicity of Acanthamoeba strains were examined. ACF showed a time- and dose-dependent amebicidal action on the trophozoites and cysts. Pat06 (A. castellanii) was the most resistant, while strain 11DS (A. hatchetti) was the most sensitive. As a result, ACF could be concluded as a new agent for the treatment of Acanthamoeba infections. On the other hand, it still needs to be further evaluated by in vivo test systems to confirm the efficiency of its biological effect.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Acriflavine; Antiprotozoal Agents; Cell Survival; Humans; Parasitic Sensitivity Tests
PubMed: 23052789
DOI: 10.1007/s00436-012-3163-8