a survey of pathogenic and free-living amoebae inhabiting swimming pool water in mexico city.a survey of pathogenic and free-living amoebae in swimming pool waters of mexico city was performed. among the organisms isolated those which have public health importance were naegleria fowleri carter and acanthamoeba castellanii douglas. amoebae of the genera acanthamoeba, naegleria, and vahlkampfia were recovered in their cystic stage while those specimens of the genera amoeba, entamoeba, thecamoeba, and vanella were recovered only in their trophic stage during this study. amoebae were concen ...19836617613
flagellum-mediated adhesion by burkholderia pseudomallei precedes invasion of acanthamoeba 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.200312654857
standardized method of measuring acanthamoeba antibodies in sera from healthy human subjects.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 individ ...200111427418
acanthamoeba interaction with extracellular matrix glycoproteins: biological and biochemical characterization and role in cytotoxicity and invasiveness.acanthamoeba are free-living amoebae that are dispersed in most environments. occasionally, acanthamoeba cause serious human infections, such as keratitis and encephalitis. during the infection process, amoebic adhesion to, and degradation of, host cells and their extracellular matrix (ecm) appear to be important requirements. we examined the interaction of acanthamoeba with the ecm, and related this event to host cell destruction and tissue invasion. pathogenic acanthamoeba culbertsoni differen ...200919527355
disinfection of burkholderia pseudomallei in potable water.the effect of chlorine, monochloramine and uv disinfection on the water-borne pathogen burkholderia pseudomallei was assessed. persistence of b. pseudomallei was verified by mpn involving a one-step recovery procedure. chlorine proved the most effective disinfectant with a 99.99% reduction of a 10(6) cfu/ml pure bacterial culture followed by 99.9% reduction by monochloramine and 99% reduction by uv. co-culture of b. pseudomallei with acanthamoeba astronyxis was found to greatly enhance survival ...200515766962
amoebae isolated from the atmosphere of mexico city and environs.a protozoological analysis was performed from june to august, 1982 to isolate small free-living amoebae from the atmosphere by using an air vacuum sampler and several filters. monoxenic medium (nonnutritive agar plus escherichia coli) and axenic medium (de jonckheere, 1977) were used to culture the isolates. the species isolated included naegleria sp. alexeieff emend. calkins, acanthamoeba polyphaga puschkarew, vahlkampfia jugosa page, acanthamoeba astronyxis ray and hayes, acanthamoeba castella ...19873803333
a specific primer pair for the diagnosis and identification of acanthamoeba astronyxis by random amplified polymorphic dna-polymerase chain reaction.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 seque ...200515856884
disseminated granulomatous acanthamoeba infection presenting as an unusual skin lesion.a fatal case of disseminated granulomatous infection with a skin lesion and focal encephalitis due to acanthamoeba astronyxis is reported. indirect fluorescent antibody tests of both tissue and serum from the patient established the diagnosis. the administration of amphotericin b is ineffective in vitro and has not been effective in vivo. it is recommended that corticosteroid therapy be avoided because it may aggravate the disease. physicians caring for diseases caused by free-living ameba may c ...1979507100
in vitro destruction of nerve cell cultures by acanthamoeba spp.: a transmission and scanning electron microscopy study.trophozoites of 4 species of acanthamoeba were cytopathic for cultured rat b103 neuroblastoma cells. cytopathogenicity was evaluated by a chromium release assay and by transmission and scanning electron microscopy. acanthamoeba culbertsoni, acanthamoeba castellanii, and acanthamoeba polyphaga destroyed b103 target cells at 37 c as evidenced by the release of radiolabel. acanthamoeba astronyxis did not produce cytopathology at 37 c but destroyed nerve cells at 25 c. transmission and scanning elec ...19968885887
the fine structure of acanthamoeba astronyxis, with special emphasis on encystment.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 ten ...19827131355
membrane carbohydrate characterization of acanthamoeba astronyxis, a. castellanii and naegleria fowleri by fluorescein-conjugated lectins.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 ...19892592141
interaction between burkholderia pseudomallei and acanthamoeba species results in coiling phagocytosis, endamebic bacterial survival, and escape.burkholderia pseudomallei causes melioidosis, a potentially fatal disease whose clinical outcomes include rapid-onset septicemia and relapsing and delayed-onset infections. like other facultative intracellular bacterial pathogens, b. pseudomallei is capable of survival in human phagocytic cells, but unlike mycobacteria, listeria monocytogenes, and salmonella serovar typhimurium, the species has not been reported to survive as an endosymbiont in free-living amebae. we investigated the consequence ...200010678988
bottled mineral waters polluted by protozoa in mexico.a survey of protozoa polluting bottled mineral water in mexico was carried out using samples obtained form the three best-selling brands of bottled mineral water in the country. the organisms were concentrated through filtration procedures and subsequently cultured in the sterile media. the cultures were observed over four weeks, with identification to the level of genus and species. most commonly found were the amoebae naegleria gruberi, acanthamoeba astronyxis, and vahlkampfia vahlkampfi (trop ...19817252885
Displaying items 1 - 13 of 13