5,420 results match your criteria Acanthamoeba


Antiamoebic properties of salicylic acid-based deep eutectic solvents for the development of contact lens disinfecting solutions against Acanthamoeba.

Mol Biochem Parasitol 2022 Jun 23:111493. Epub 2022 Jun 23.

Department of Clinical Sciences, College of Medicine, University of Sharjah, University, City, Sharjah, 27272, United Arab Emirates. Electronic address:

Acanthamoeba castellanii is a protist pathogen that can cause sight-threatening keratitis and a fatal infection of the central nervous system, known as granulomatous amoebic encephalitis. In this study, effects of five malonic acid and salicylic acid-based deep eutectic solvents (DES) on A. castellanii were investigated. Read More

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Antiprotozoal activity of different Xenorhabdus and Photorhabdus bacterial secondary metabolites and identification of bioactive compounds using the easyPACId approach.

Sci Rep 2022 Jun 24;12(1):10779. Epub 2022 Jun 24.

Department of Biology, Faculty of Arts and Science, Aydin Adnan Menderes University, Aydin, Türkiye.

Natural products have been proven to be important starting points for the development of new drugs. Bacteria in the genera Photorhabdus and Xenorhabdus produce antimicrobial compounds as secondary metabolites to compete with other organisms. Our study is the first comprehensive study screening the anti-protozoal activity of supernatants containing secondary metabolites produced by 5 Photorhabdus and 22 Xenorhabdus species against human parasitic protozoa, Acanthamoeba castellanii, Entamoeba histolytica, Trichomonas vaginalis, Leishmania tropica and Trypanosoma cruzi, and the identification of novel bioactive antiprotozoal compounds using the easyPACId approach (easy Promoter Activated Compound Identification) method. Read More

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Correlation of ex vivo and in vivo confocal microscopy imaging of .

Br J Ophthalmol 2022 Jun 24. Epub 2022 Jun 24.

External Disease, Moorfields Eye Hospital, London, UK.

Background/aims: The aim of this study was to correlate the various forms of on ex vivo confocal microscopy (EVCM) with in vivo confocal microscopy (IVCM) and findings from cultured positive cases of .

Methods: live, dead and empty cysts, and live trophozoites were prepared in vitro and inoculated into porcine cornea using a sterile 26-gauge needle and examined ex vivo using the Heidelberg Retina Tomograph II/Rostock Corneal Module. IVCM images from 12 cultured positive cases, obtained using the same instrument, were compared with EVCM findings. Read More

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Surveillance of Amoebic Keratitis-Causing Acanthamoebae for Potential Bacterial Endosymbionts in Ontario, Canada.

Pathogens 2022 Jun 8;11(6). Epub 2022 Jun 8.

Tropical Disease Unit, Division of Infectious Diseases, UHN-Toronto General Hospital, Toronto, ON M5G 2C4, Canada.

spp. are the causative pathogens of several infections, including amoebic keratitis (AK), a vision-threatening infection. Acanthamoebae from corneal specimens of patients with AK harbor bacterial endosymbionts, which may increase virulence. Read More

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Comparative Evaluation of Antimicrobial, Antiamoebic, and Antiviral Efficacy of Ophthalmic Formulations.

Microorganisms 2022 Jun 4;10(6). Epub 2022 Jun 4.

Department of Pharmacy, University of Salerno, 84084 Fisciano, Italy.

The extensive use of ophthalmic antibiotics is contributing to the appearance of resistant bacterial strains, which require prolonged and massive treatments with consequent detrimental outcomes and adverse effects. In addition to these issues, antibiotics are not effective against parasites and viruses. In this context, antiseptics could be valuable alternatives. Read More

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Tannic Acid-Modified Silver Nanoparticles in Conjunction with Contact Lens Solutions Are Useful for Progress against the Adhesion of spp. to Contact Lenses.

Microorganisms 2022 May 24;10(6). Epub 2022 May 24.

Parasitology Laboratory, Department of Medical Biology, Medical University of Warsaw, Litewska 14/16, 00-575 Warsaw, Poland.

spp. are amphizoic amoebae that are widely distributed in the environment and capable of entering the human body. They can cause pathogenic effects in different tissues and organs, including keratitis (AK), which may result in a loss of visual acuity and blindness. Read More

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Potential role of Acanthamoeba Rab7.

Exp Parasitol 2022 Jun 20;239:108312. Epub 2022 Jun 20.

Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Parasitology, College of Medicine, National Cheng Kung University, Tainan, Taiwan. Electronic address:

Acanthamoeba castellanii is a free-living protozoan that causes several severe human parasitic diseases such as Acanthamoeba keratitis and granulomatous encephalitis. A. castellanii feeds on bacteria, yeasts, and other organic particles as food sources, but the mechanisms of digestion in acanthamoebal cells are unclear. Read More

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Homodimerization Counteracts the Detrimental Effect of Nitrogenous Heme Ligands on the Enzymatic Activity of CYP51.

Biochemistry 2022 Jun 22. Epub 2022 Jun 22.

Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California 92093, United States.

is a free-living amoeba that can cause severe eye and brain infections in humans. At present, there is no uniformly effective treatment for any of these infections. However, sterol 14α-demethylases (CYP51s), heme-containing cytochrome P450 enzymes, are known to be validated drug targets in pathogenic fungi and protozoa. Read More

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Evaluation of Nanoparticles with 5-Fluorouracil and Chloroquine on Acanthamoeba castellanii activity.

Mol Biochem Parasitol 2022 Jun 14:111492. Epub 2022 Jun 14.

Department of Clinical Sciences, College of Medicine, University of Sharjah, UAE; Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates.

Acanthamoeba is opportunistic pathogens that cause vision-threatening Acanthamoeba keratitis (AK). Previous studies proposed the use of chloroquine (CQ) and 5-fluorouracil (5FU) as anti-Acanthamoeba agents. The objective of this study was to determine the benefit of using 5FU and CQ nanoparticles (NP) formulations against A. Read More

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Recognition of Cell Wall Mannosylated Components as a Conserved Feature for Fungal Entrance, Adaptation and Survival Within Trophozoites of and Murine Macrophages.

Front Cell Infect Microbiol 2022 31;12:858979. Epub 2022 May 31.

Laboratório de Bioquímica e Imunologia das Micoses, Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil.

() is a species of free-living amoebae (FLAs) that has been widely applied as a model for the study of host-parasite interactions and characterization of environmental symbionts. The sharing of niches between and potential pathogens, such as fungi, favors associations between these organisms. Through predatory behavior, enhances fungal survival, dissemination, and virulence in their intracellular milieu, training these pathogens and granting subsequent success in events of infections to more evolved hosts. Read More

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[Etiological analysis of infectious keratitis in children from 2007 to 2016].

Zhonghua Yan Ke Za Zhi 2022 Jun;58(6):433-440

Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Institute of Ophthalmology, Beijing Key Laboratory of Ophthalmology & Visual Sciences, Beijing 100730, China.

To analyze the etiological changes of children with infectious keratitis. Retrospective study. Data of patients diagnosed as bacterial, fungal, and amoebic keratitis from 2007 to 2016, aged no more than 14 years old, were collected in the Department of Ophthalmology, Beijing Tongren Hospital. Read More

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Biofilm formation of Salmonella enterica serovar Enteritidis cocultured with Acanthamoeba castellanii responds to nutrient availability.

Int Microbiol 2022 Jun 8. Epub 2022 Jun 8.

Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada.

Acanthamoeba spp. and Salmonella share common habitats, and their interaction may influence the biofilm-forming ability of Salmonella. In this study, biofilm formation of Salmonella enterica serovar Enteritidis cocultured with Acanthamoeba castellanii was examined in nutrient-rich and nutrient-deficient media. Read More

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Anaerobic ATP synthesis pathways and inorganic phosphate transport and their possible roles in encystment in Acanthamoeba castellanii.

Cell Biol Int 2022 Jun 8. Epub 2022 Jun 8.

Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil.

Acanthamoeba castellanii is the etiological agent of amoebic keratitis and is present in the environment in trophozoite or cyst forms. Both forms can infect the vertebrate host and colonize different tissues. The high resistance of cysts to standard drugs used in clinics contributes to the lack of effective treatments. Read More

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Pathogenic free-living amoebae from water sources in Cape Verde.

Parasitol Res 2022 Jun 4. Epub 2022 Jun 4.

Instituto Universitario de Enfermedades Tropicales Y Salud Pública de Canarias (IUETSPC), Universidad de La Laguna (ULL), Avda. Astrofísico Fco. Sánchez S/N, 38203, La Laguna, Tenerife, Spain.

Free-living amoebae (FLA) are protozoa which have been reported in different countries worldwide from diverse sources (water, soil, dust, air), contributing to the environmental microbiological contamination. Most of the FLA species present a life cycle with two different phases: an active vegetative and physiologically form named trophozoite, and an extremely resistant phase called cyst. Acanthamoeba spp. Read More

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Environmental water surveillance for free-living amoeba in North India.

Indian J Med Microbiol 2022 May 31. Epub 2022 May 31.

Department of Medical Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

Purpose: Free-living amoebae (FLA) exist in various environmental sources and are the causative agents of many serious human diseases. We surveyed various natural and artificial water bodies in areas of north India to detect the presence of FLA species.

Materials And Methods: Surface water samples were collected from 29 water bodies and subjected to microscopy, non-nutrient agar (NNA) culture, and various polymerase chain reaction (PCR) assays for the detection of FLA. Read More

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Isobenzofuran-1(3H)-one derivatives: Amoebicidal activity and program cell death in Acanthamoeba castellanii Neff.

Biomed Pharmacother 2022 Jun 6;150:113062. Epub 2022 May 6.

Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias, Universidad de La Laguna (ULL), Tenerife 38206, Spain; Departamento de Obstetricia, Ginecología, Pediatría, Medicina Preventiva y Salud Pública, Toxicología, Medicina Legal y Forense y Parasitología, Universidad De La Laguna, La Laguna, Tenerife 38203, Islas Canarias, Spain; Red de Investigación Cooperativa en Enfermedades Tropicales (RICET), Spain; CIBER de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, 28029 Madrid, Spain. Electronic address:

The genus Acanthamoeba is characterized by being a group of ubiquitous and free-living amoebae that inhabit a variety of environments. Generally, human infections by this parasite are associated with Acanthamoeba keratitis, especially in contact lens wearers, and with chronic but fatal granulomatous amoebic meningoencephalitis. Current treatments used for eradication of amoeba from infection sites represent a challenge for pharmacotherapy, due to the lack of effective treatment and the amoebae highly resistant to anti-amoebic drugs. Read More

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Bacterial isolates and antimicrobial susceptibility pattern of ocular infection at a tertiary referral hospital in the South of Italy.

Eur J Ophthalmol 2022 May 31:11206721221106139. Epub 2022 May 31.

Section of Ophthalmology, Department of Basic Medical Science, Neuroscience and Sense Organs, 9295University of Bari, Bari, Italy.

Purpose: The present study aimed to determine the prevalence of bacterial and fungal infections of the eye and also to assess the antibiotic susceptibility pattern of bacterial isolates at a tertiary referral eye care hospital in Bari, Italy.

Methods: Two hundred seventy three samples collected during a 2-year observation period. Culture, Gram's stain, potassium hydroxide mount and occasionally Giemsa staining was done for the clinical specimens. Read More

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Inhibition of Acanthamoeba polyphaga by Chlorhexidine mediated oxidative stress response.

J Glob Antimicrob Resist 2022 May 28. Epub 2022 May 28.

Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias, Universidad de La Laguna (ULL), Tenerife, 38206, Spain; Departamento de Obstetricia, Ginecología, Pediatría, Medicina Preventiva y Salud Pública, Toxicología, Medicina Legal y Forense y Parasitología, Universidad De La Laguna, La Laguna, Tenerife, 38203 Islas Canarias, Spain; Red de Investigación Cooperativa en Enfermedades Tropicales (RICET); CIBER de Enfermedades Infecciosas, Instituto de Salud Carlos III, 28029, Madrid, Spain.

Acanthamoeba keratitis, is a severe corneal infection caused by an ubiquitous opportunistic protozoan pathogen known as Acanthamoeba. On the last decade, the current therapy approach to treat this infection usually include the use of polyhexamethylene biguanide (0.02%) or/ and chlorhexidine (0. Read More

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Free-living amoebae in an oil refinery wastewater treatment facility.

Sci Total Environ 2022 Sep 27;839:156301. Epub 2022 May 27.

University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Nicosia University Medical School, Department of Basic and Clinical Sciences, Nicosia 2408, Cyprus.

Free Living Amoebae (FLA) are ubiquitous microorganisms reported from harsh environmental conditions. Oil refinery facilities consume vast volumes of water during their processes, generating a large amount of wastewater. The present study aimed to evaluate the wastewater treatment process in an oil refinery wastewater treatment facility (ORWWTF) for the presence of FLA. Read More

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September 2022

New Insights in .

Pathogens 2022 May 23;11(5). Epub 2022 May 23.

Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias, Universidad de La Laguna (ULL), 38206 Tenerife, Spain.

is a free-living amoeba genus able to cause severe infections, such as Granulomatous amoebic encephalitis (GAE), epithelial disorders and a sight-threatening disease called keratitis (AK) [... Read More

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5-Nitroindazole derivatives as potential therapeutic alternatives against Acanthamoeba castellanii.

Acta Trop 2022 Aug 23;232:106538. Epub 2022 May 23.

Department of Parasitology, University of Granada, Severo Ochoa s/n, E-18071, Granada, Spain. Electronic address:

Amoebas of the genus Acanthamoeba are distributed worldwide, including species with a high pathogenic capacity for humans. In a similar way to what occurs with other parasitic protozoa, the available treatments show variable effectiveness in addition to high toxicity, which demands the development of new treatments. Positive results of 5-nitroindazole derivatives against several protozoa parasites suggest that these compounds may be a promising tool for the development of efficient antiparasitic drugs. Read More

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Isolation of Giant Viruses of Acanthamoeba castellanii.

Curr Protoc 2022 May;2(5):e455

Instituto de Ciências Biológicas, Departamento de Microbiologia, Laboratório de Vírus, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.

This article describes a practical method for prospecting and isolating giant viruses based on direct inoculation of environmental samples into amoeba cultures of Acanthamoeba castellanii. The giant viruses that infect amoebas have already been isolated from various environmental samples in several countries worldwide, including in extreme environments. Here we describe the methodologic procedures regarding the prospecting of giant viruses in A. Read More

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Infectious keratitis: A review.

Clin Exp Ophthalmol 2022 May 24. Epub 2022 May 24.

Save Sight Institute, Discipline of Ophthalmology, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.

Globally, infectious keratitis is the fifth leading cause of blindness. The main predisposing factors include contact lens wear, ocular injury and ocular surface disease. Staphylococcus species, Pseudomonas aeruginosa, Fusarium species, Candida species and Acanthamoeba species are the most common causal organisms. Read More

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Detection of Mimivirus from respiratory samples in tuberculosis-suspected patients.

Sci Rep 2022 May 23;12(1):8676. Epub 2022 May 23.

Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran.

Acanthamoeba polyphaga mimivirus (APMV), a species of amoeba-infecting giant viruses, has recently emerged as human respiratory pathogens. This study aimed to evaluate the presence of Mimivirus in respiratory samples, collected from tuberculosis (TB)-suspected patients. The study was performed on 10,166 clinical respiratory samples from April 2013 to December 2017. Read More

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Characterization of Glucokinases from Pathogenic Free-Living Amoebae.

Antimicrob Agents Chemother 2022 Jun 23;66(6):e0237321. Epub 2022 May 23.

Eukaryotic Pathogens Innovation Center, Department of Genetics and Biochemistry, Clemson Universitygrid.26090.3d, Clemson, South Carolina, USA.

Infection with pathogenic free-living amoebae, including Naegleria fowleri, spp., and Balamuthia mandrillaris, can lead to life-threatening illnesses, primarily because of catastrophic central nervous system involvement. Efficacious treatment options for these infections are lacking, and the mortality rate due to infection is high. Read More

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Diversity of Giant Viruses Infecting .

Front Microbiol 2022 22;13:808499. Epub 2022 Apr 22.

MEPHI, APHM, IRD 198, Aix Marseille University, IHU-Méditerranée Infection, Marseille, France.

The discovery of Acanthamoeba polyphaga mimivirus in 2003 using the free-living amoeba caused a paradigm shift in the virology field. Twelve years later, using another amoeba as a host, i.e. Read More

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Neurotrophic Factors in Experimental Cerebral Acanthamoebiasis.

Int J Mol Sci 2022 Apr 29;23(9). Epub 2022 Apr 29.

Independent Laboratory of Pharmaceutical Botany, Pomeranian Medical University in Szczecin, 70-204 Szczecin, Poland.

To date, no studies have addressed the role of neurotrophins (NTs) in spp. infections in the brain. Thus, to clarify the role of NTs in the cerebral cortex and hippocampus during experimental acanthamoebiasis in relation to the host immune status, the purpose of this study was to determine whether spp. Read More

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Acanthamoeba keratitis: an increasingly common infectious disease of the cornea.

Lancet Microbe 2021 08 25;2(8):e345-e346. Epub 2021 May 25.

School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia.

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Well water sources simultaneous contamination with Cryptosporidium and Acanthamoeba in East-Southeast Asia and Acanthamoeba spp. in biofilms in the Philippines.

Sci Total Environ 2022 Sep 6;837:155752. Epub 2022 May 6.

University of Cologne, Faculty of Medical and University Hospital Cologne, Cologne 50923, Germany; Medical School, Department of Basic and Clinical Science, University of Nicosia, Nicosia, 2417, Cyprus. Electronic address:

Cryptosporidium is the leading agent of waterborne parasitic protozoan outbreaks and is the second leading cause of infant mortality due to diarrhoea worldwide. Acanthamoeba spp. causes Acanthamoeba keratitis (AK) and a life-threatening condition known as granulomatous amoebic encephalitis (GAE). Read More

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September 2022