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Parasitology Research 1988Using agarose isoelectric focusing, the isoenzymes of 19 Acanthamoeba strains were investigated. They had been isolated from nasal mucosa, and the species identification...
Using agarose isoelectric focusing, the isoenzymes of 19 Acanthamoeba strains were investigated. They had been isolated from nasal mucosa, and the species identification based on morphology of the cyst had previously been reported. The identification by isoenzymes differed from that by cystic morphology. Growth at 40 degrees C correlated with the species identification by isoenzymes. Six strains were identified as A. lenticulata, nine as A. mauritaniensis, one as A. rhysodes, and three belonged to the A. lugdunensis-A. quina complex. Several of the nasal A. lenticulta isolates proved to be highly virulent for mice.
Topics: Acanthamoeba; Amebiasis; Animals; Humans; Isoelectric Focusing; Isoenzymes; Mice; Nasal Mucosa; Virulence
PubMed: 3387404
DOI: 10.1007/BF00539451 -
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng... Apr 2016To identify the species of a morphologically Acanthamoeba-like pathogen in sputum from a patient with repeated cough.
OBJECTIVE
To identify the species of a morphologically Acanthamoeba-like pathogen in sputum from a patient with repeated cough.
METHODS
Protozoa were isolated from the sputum and cultured for morphological observation of the trophozoites and cysts. DNA was extracted from the cultivated sample, and PCR was performed using primers as follows: 18S universal primers for amoeba family(Ami6F1 and Ami9R) and for amoeba genus(JDP1 and JDP2), and primers for 18S full-length sequence of S-7 ATCC reference strain of Acanthamoeba griffini (AacGF and AscGR). The 18S rRNA was sequenced, followed by homology analysis. The maximum likelihood method was used to construct phylogenetic tree.
RESULTS
Microscopic examination showed that the trophozites had spine and irregular-shape pseudopodia bulge. The cysts were encapsulated by double membrane layer with the inner membrane having star-like processes. As expected, PCR amplification resulted in bands of 830, 479 and 1 957 bp, respectively, which were blasted to be 99%, 99% and 100% homologous to those of A. griffini(U07412.1). Phylogenetic tree indicated that this acanthamobe in the patient’s sample was 91.4%, 99.6%, 94.5% and 91.8% homologous to keratitis-associated A. castellanii, A. polyphage, A. cullbertsoni and A. rhysodes.
CONCLUSION
The parasite in sputum of the patient with respiratory tract infection is Acanthamoeba griffini.
Topics: Acanthamoeba; Animals; Base Sequence; DNA Primers; DNA, Protozoan; Humans; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 18S; Respiratory Tract Infections
PubMed: 30124240
DOI: No ID Found -
Eye & Contact Lens Jan 2009Effective pharmacotherapy for Acanthamoeba keratitis has been hampered because of the marked resistance of various stains to a variety of antimicrobial agents. In view...
OBJECTIVES
Effective pharmacotherapy for Acanthamoeba keratitis has been hampered because of the marked resistance of various stains to a variety of antimicrobial agents. In view of the fact that topical Brolene (propamidine isethionate) and neosporin are currently considered to be the first-line medical treatment of choice in Europe, we sought to determine whether Alexidine is equally effective, because the latter drug is more readily available in the United States.
METHODS
Trophozoites and cysts from 3 pathogenic corneal isolates (A. castellanii, A. polyphaga, and A. rhysodes) were incubated in peptone-yeast extract-glucose medium containing different concentrations of Alexidine for 24 hr. The number of trophozoites was counted by hemocytometer. The cysts were plated in to nonnutrient agar plates precoated with Escherichia coli and observed for viability or excystment over a period of 2 weeks. The capacity of different concentrations of Alexidine to induce cytolysis of corneal epithelial cells was tested in vitro. Chinese hamster corneas were treated with 5 microL of Alexidine topically, every hour; 6 times a day and the corneas were stained with fluorescein to asses the epithelial defects in vivo.
RESULTS
Alexidine was effective in killing the trophozoites at a concentration of 10 microg/mL. However, a higher concentration of Alexidine (100 microg/mL) is required to kill Acanthamoeba cysts and the cytotoxic activities of Alexidine are comparable with chlorhexidine. We have also demonstrated that both Alexidine and chlorhexidine at 100 microg/mL induced significant cytopathic effect on the corneal epithelial cells in vitro. In vivo results indicate that Alexidine at a concentration of 100 microg/mL is less toxic than chlorhexidine when applied topically to the Chinese hamster cornea.
CONCLUSIONS
Our study has identified Alexidine as a novel anti-Acanthamoeba drug and suggests that Alexidine may be an effective therapeutic option because of its potency and low toxicity to the corneal tissues when applied topically in vivo.
Topics: Acanthamoeba; Administration, Topical; Amebiasis; Amebicides; Animals; Biguanides; Chlorhexidine; Cornea; Cricetinae; Cricetulus; Dose-Response Relationship, Drug; Epithelium, Corneal; Parasitic Sensitivity Tests; Trophozoites
PubMed: 19125040
DOI: 10.1097/ICL.0b013e3181909ae6 -
Parasitology Research 1991The isoenzyme pattern of an Acanthamoeba, stock H-1, isolated from a patient with keratitis (Krankenhaus Heidberg, Hamburg) was compared with that of two strains of A....
The isoenzyme pattern of an Acanthamoeba, stock H-1, isolated from a patient with keratitis (Krankenhaus Heidberg, Hamburg) was compared with that of two strains of A. quina-A. lugdunensis (302-2, 312-1), two stocks of A. lenticulata (45, 89-1) and one strain of A. rhysodes (302-1). The isolated stock showed glucose-6-phosphate dehydrogenase (G-6-PDH), beta-hydroxybutyric dehydrogenase (beta-HBDH), alcohol dehydrogenase (ADH) and superoxide dismutase (SOD) isoenzyme patterns similar to those of A. quina-A. lugdunensis but their acid phosphatase (AP) patterns differed. Furthermore, cyst morphology showed that the patient-isolated stock belongs to group II of the taxonomic classification of Acanthamoeba. This stock was not thermophilic and exhibited non-pathogenic properties after its intranasal instillation into NMRI mice, whereas it killed BALB/c mice. Immunofluorescent studies revealed the presence of antibodies against Acanthamoeba in the patient's serum. Immunoblotting experiments showed that a 45-kDa protein reacted with this serum. Such an antigen was also detected in A. quina-A. lugdunensis and A. lenticulata. Lectin reactions with Canavalia ensiformis, Ricinus communis-120, Lotus tetragonolobus, Ulex europaeus I, Helix pomatia, Arachis hypogaea, Triticum vulgaris, Glycine maxima, Bauhinia purpurea and Mycoplasma gallisepticum demonstrated that only the A. lenticulata stocks could not be distinguished and that the H-1 stock was more similar to the A. lugdunensis 302-2 strain than to the other acanthamoebae.
Topics: Acanthamoeba; Acanthamoeba Keratitis; Adult; Agglutination Tests; Animals; Biological Assay; Cell Nucleus; Cornea; Humans; Isoenzymes; Male; Mice
PubMed: 1924251
DOI: 10.1007/BF00928411 -
Neurology Dec 1991A 39-year-old man with AIDS died after developing a variety of neurologic symptoms and signs. CT showed multiple enhancing lesions in the cerebral hemispheres and...
A 39-year-old man with AIDS died after developing a variety of neurologic symptoms and signs. CT showed multiple enhancing lesions in the cerebral hemispheres and cerebellum. Postmortem examination revealed parenchymal hemorrhagic and necrotizing lesions with a thrombo-occlusive vasculitis due to Acanthamoeba, which was typed as Acanthamoeba group 2, probably A rhysodes, by immunofluorescence.
Topics: Acanthamoeba; Acquired Immunodeficiency Syndrome; Adult; Amebiasis; Animals; Brain; Encephalitis; Granuloma; Humans; Male; Tomography, X-Ray Computed
PubMed: 1745363
DOI: 10.1212/wnl.41.12.1993 -
Experimental Parasitology Sep 2010Several species of free-living amoebae can cause disease in humans. However, in addition to the direct pathogenicity of e.g. Acanthamoebae and Naegleria species, they...
Several species of free-living amoebae can cause disease in humans. However, in addition to the direct pathogenicity of e.g. Acanthamoebae and Naegleria species, they are recognized as environmental hosts, indirectly involved in the epidemiology of many pathogenic bacteria. Although several studies have demonstrated intracellular survival of many different bacteria in these species, the extent of such interactions as well as the implications for the epidemiology of the bacterial species involved, are largely unknown and probably underestimated. In this study, we evaluated eight different unicellular eukaryotic organisms, for their potential to serve as environmental hosts for Campylobacter species. These organisms include four amoebozoas (Acanthamoeba polyphaga, Acanthamoeba castellanii, Acanthamoeba rhysodes and Hartmanella vermiformis), one alveolate (Tetrahymena pyriformis), one stramenopile (Dinobryon sertularia), one eugoenozoa (Euglena gracilis) and one heterolobosea (Naegleria americana). Campylobacter spp. including Campylobacter jejuni, Campylobacter coli and Campylobacter lari are the most common cause of gastroenteritis in the western world. Survival and replication of these three species as well as Campylobacter hyointestinalis were assessed in co-cultures with the eukaryotic organisms. Campylobacter spp. generally survived longer in co-cultures, compared to when incubated in the corresponding growth media. The eukaryotic species that best promoted bacterial survival was the golden algae D. sertularia. Three species of amoebozoas, of the genus Acanthamoeba promoted both prolonged survival and replication of Campylobacter spp. The high abundance in lakes, ponds and water distribution networks of these organisms indicate that they might have a role in the epidemiology of campylobacteriosis, possibly contributing to survival and dissemination of these intestinal pathogens to humans and other animals. The results suggest that not only C. jejuni, but a variety of Campylobacter spp. can interact with different eukaryotic unicellular organisms.
Topics: Acanthamoeba; Campylobacter; Coculture Techniques; Eukaryota; Humans
PubMed: 20056117
DOI: 10.1016/j.exppara.2009.12.016 -
Applied and Environmental Microbiology Mar 1977Cyst walls of Acanthamoeba rhysodes, A. palestinensis, A. castellanii, and one other strain of Acanthamoeba contain 36 to 45% protein and 20 to 34% carbohydrate. More...
Cyst walls of Acanthamoeba rhysodes, A. palestinensis, A. castellanii, and one other strain of Acanthamoeba contain 36 to 45% protein and 20 to 34% carbohydrate. More than half of the protein in the walls of A. palestinensis, A. castellanii and Acanthamoeba sp. is accessible to and hydrolyzed by protease, and 67 to 69% of the carbohydrate of A. palestinensis and A. rhysodes walls is hydrolyzed by cellulase. The extent of hydrolysis of walls of the other amoebae by these enzymes is appreciably less, and chitinase and beta-1,3-glucanase have no detectable effect. Protease solubilizes 10% or less of the weight of intact cysts, and no solubilization is observed with cellulase. Walls of A. palestinensis are extensively degraded in soil, the activity is less with A. rhysodes, and little attack on the other amoebae occurs. When added to soil, the protozoa excyst and grow for short periods, the trophozoites then die, and chiefly cysts persist thereafter.
PubMed: 16345225
DOI: 10.1128/aem.33.3.670-674.1977 -
Journal of the Egyptian Society of... Aug 1994Samples from different water sources of Alexandria, and from nasal passages of 500 healthy children inhabiting areas nearby these sources were examined for the presence...
Samples from different water sources of Alexandria, and from nasal passages of 500 healthy children inhabiting areas nearby these sources were examined for the presence of free-living amoebae. These samples were cultured on 1.5% non nutrient agar streaked with bacteria. Amoebae were isolated and identified by means of their morphological characters and ability to produce flagellated forms. Characteristics of the cystic stages and pattern of excystation also aided in the identification of the various species. Nine species, Naegleria gruberi, N. fowleri, Acanthamoeba rhysodes, A. glebae, A. culbertsoni, A. astronyxis, A. palestinensis, V. avara and V. inornata were isolated from the water of canals and drains. N. gruberi and A. rhysodes were found in the nasal passages of six healthy children living near the contaminated canals. No amoebae were encountered in the drinking water, swimming pools, sea and lake water included in this study.
Topics: Acanthamoeba; Amoeba; Animals; Child; Egypt; Humans; Naegleria; Nasal Mucosa; Water
PubMed: 8077745
DOI: No ID Found -
Transactions of the Royal Society of... 1984Primary meningoencephalitis caused by Naegleria fowleri was documented in a 16-year-old male from Mexicali in the state of Baja California in Mexico. In August 1978,...
Primary meningoencephalitis caused by Naegleria fowleri was documented in a 16-year-old male from Mexicali in the state of Baja California in Mexico. In August 1978, seven days after sustaining moderate head trauma while swimming in a shallow, stagnant irrigation ditch on a hot summer day, the patient presented an acute illness with severe headache, fever and convulsions rapidly progressing into a comatose state. Actively moving trophozoites were observed in the spinal fluid on admission. The patient died shortly after admission to hospital on the third day of symptoms. Post-mortem examination revealed a meningoencephalitis with extensive destruction, haemorrhage and numerous parasites involving structures of the posterior fossa. Immunoperoxidase strains of trophozoites in meningeal and cerebellar tissue were positive for N. fowleri KUL and negative for N. gruberi, N. australiensis and Acanthamoeba rhysodes. This appears to be the first documented case of the disease in Mexico.
Topics: Adolescent; Amebiasis; Humans; Male; Meningoencephalitis; Mexico
PubMed: 6485064
DOI: 10.1016/0035-9203(84)90084-1 -
Annales de Parasitologie Humaine Et... 1980The present study was performed with the help of scanning electron microscope and refers to the external morphology of the cysts of the free-living amoebae. The amoebae... (Comparative Study)
Comparative Study
The present study was performed with the help of scanning electron microscope and refers to the external morphology of the cysts of the free-living amoebae. The amoebae belonging to the genus Naegleria form cysts whose outer layer shows no wrinkles. It can be smooth (N. fowleri) or rough (N. gruberi). The average number of pores varies between 1.2 and 7.2. Their margin can be smooth (N. fowleri) or pierced (N. gruberi). The thickness of the bordering cell wall varies between 0.4 and 1.0 micrometer and that of the pore is about 0.6 micrometer. The cysts of the genera Schizopyrenus, Tetramitus and Didascalus are very small, show no wrinkles in their cell wall and contain no pores. In contrast, cysts in the general Acanthamoeba show their outer layer superficially plugged with a lesser number of wrinkles (A. rhysodes, A. culbertsoni) or with large or deep wrinkles inside their wall (. castellanii, A. polyphaga). There are no pores observed in their cysts. Thus the distinguishing morphological features of the cysts have generated important role in the taxonomy of the amoebae of the limax-group.
Topics: Amoeba; Animals; Hartmannella; Microscopy, Electron, Scanning
PubMed: 7469305
DOI: No ID Found