1
|
Various brain-eating amoebae: the protozoa, the pathogenesis, and the disease. Front Med 2021; 15:842-866. [PMID: 34825341 DOI: 10.1007/s11684-021-0865-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 04/25/2021] [Indexed: 10/19/2022]
Abstract
Among various genera of free-living amoebae prevalent in nature, some members are identified as causative agents of human encephalitis, in which Naegleria fowleri followed by Acanthamoeba spp. and Balamuthia mandrillaris have been successively discovered. As the three dominant genera responsible for infections, Acanthamoeba and Balamuthia work as opportunistic pathogens of granulomatous amoebic encephalitis in immunocompetent and immunocompromised individuals, whereas Naegleria induces primary amoebic meningoencephalitis mostly in healthy children and young adults as a more violent and deadly disease. Due to the lack of typical symptoms and laboratory findings, all these amoebic encephalitic diseases are difficult to diagnose. Considering that subsequent therapies are also affected, all these brain infections cause significant mortality worldwide, with more than 90% of the cases being fatal. Along with global warming and population explosion, expanding areas of human and amoebae activity in some regions lead to increased contact, resulting in more serious infections and drawing increased public attention. In this review, we summarize the present information of these pathogenic free-living amoebae, including their phylogeny, classification, biology, and ecology. The mechanisms of pathogenesis, immunology, pathophysiology, clinical manifestations, epidemiology, diagnosis, and therapies are also discussed.
Collapse
|
2
|
Ziaei Hezarjaribi H, Toluee E, Saberi R, Dadi Moghadam Y, Fakhar M, Akhtari J. In vitro anti- Acanthamoeba activity of the commercial chitosan and nano-chitosan against pathogenic Acanthamoeba genotype T4. J Parasit Dis 2021; 45:921-929. [PMID: 34789973 DOI: 10.1007/s12639-021-01380-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 03/09/2021] [Indexed: 10/21/2022] Open
Abstract
Acanthamoeba keratitis (AK) is a rare but serious infection of the eye and can lead to blindness. The effective and safe medical therapy remains unclear for AK until present. Antimicrobial activity and biological characteristic of chitosan encourage screening of it against Acanthamoeba. Thus, in vitro anti-amoebic activities of commercial chitosan and nano-chitosan were tested on pathogenic Acanthamoeba genotype T4, a causative agent of human AK. The Acanthamoeba spp. was isolated from the keratitis patient. The Acanthamoeba genotype T4 was approved using PCR method followed by sequencing technique. Chitosan nanoparticles was prepared using ionic gelation method and characterized by their physicochemical properties. In the present study, the in vitro activity of serial dilutions (12.5, 25, 50, 100, and 200 µL/mL) of commercial chitosan and nano-chitosan were evaluated against Acanthamoeba trophozoites and cysts. The finding of nano-chitosan particle size by DLS was 118 nm with a PDI of about 0.134. Zeta potential value was found to be 42.7 mV. The obtained results showed that the tested chitosan and nano-chitosan presented anti-amoebic activities dependent to time and concentration. The inhibitory effect of the chitosan and nano-chitosan is enhanced by increasing the concentration and incubation time. The inhibitory effect of nano-chitosan on both trophozoites and cyst was more than chitosan. According to the results, nano-chitosan shows the potent activity against Acanthamoeba T4 and could be used for the development of novel and safe therapeutic approaches in the future.
Collapse
Affiliation(s)
- Hajar Ziaei Hezarjaribi
- Department of Parasitology, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.,Department of Parasitology, Toxoplasmosis Research Center, Communicable Diseases Institute, School of Medicine, Mazandaran University of Medical Sciences, PO Box 48471-91971, Sari, Iran
| | - Elahe Toluee
- Department of Parasitology, Molecular and Cell Biology Research Center, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.,Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Reza Saberi
- Department of Parasitology, Toxoplasmosis Research Center, Communicable Diseases Institute, School of Medicine, Mazandaran University of Medical Sciences, PO Box 48471-91971, Sari, Iran.,Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Yousef Dadi Moghadam
- Department of Parasitology, Toxoplasmosis Research Center, Communicable Diseases Institute, School of Medicine, Mazandaran University of Medical Sciences, PO Box 48471-91971, Sari, Iran.,Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mahdi Fakhar
- Department of Parasitology, Toxoplasmosis Research Center, Communicable Diseases Institute, School of Medicine, Mazandaran University of Medical Sciences, PO Box 48471-91971, Sari, Iran.,Iranian National Registry Center for Lophomoniasis and Toxoplasmosis, Imam Khomeini Hospital, Mazandaran University of Medical Sciences, Sari, Iran
| | - Javad Akhtari
- Department of Medical Nanotechnology, Faculty of Medicine, Toxoplasmosis Research Center, Communicable Diseases Institute, Mazandaran University of Medical Sciences, Sari, Iran
| |
Collapse
|
3
|
Nikhat S, Fazil M. Overview of Covid-19; its prevention and management in the light of Unani medicine. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 728:138859. [PMID: 32334163 PMCID: PMC7174982 DOI: 10.1016/j.scitotenv.2020.138859] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 04/18/2020] [Accepted: 04/19/2020] [Indexed: 05/04/2023]
Abstract
Since December 2019, a respiratory pandemic named as coronavirus disease 2019 (Covid-19) caused by a new coronavirus named as SARS-CoV-2, has taken the world by storm. The symptoms are fever, malaise, and cough which resolve in a few days in most cases; but may progress to respiratory distress and organ failure. Transmission is through droplet infection or fomites, but other modes such as airborne transmission and oro-fecal transmission are also speculated. Research is underway to develop effective vaccines and medicines for the disease. In such a scenario, we present the measures described in Unani system of medicine for health protection during epidemics. Unani is a traditional system of medicine developed during the middle ages, which employs natural drugs of herbal, animal and mineral origin for treatment. In Unani medicine, during an epidemic, apart from isolation and quarantine, three measures are of utmost importance, (i) purification of surroundings using certain herbal drugs as fumigants or sprays, (ii) health promotion and immune-modulation, and (iii) use of health-protecting drugs and symptom-specific drugs. Drugs such as loban (Styrax benzoides W. G. Craib), sandroos (Hymenaea verrucosa Gaertn.) za'fran (Crocus sativus L.), vinegar etc. are prescribed in various forms. Scientific researches on these drugs reveal the presence of a number of pharmacologically active substances, which may provide a new insight into the management of infections and epidemics.
Collapse
Affiliation(s)
- Sadia Nikhat
- Dept. of Ilaj bit Tadbeer, School of Unani Medical Education and Research, Jamia Hamdard, New Delhi 110062, India.
| | - Mohammad Fazil
- HAK Institute of Literary and Historical Research in Unani Medicine, CCRUM, Jamia Millia Islamia Campus, New Delhi 110025, India.
| |
Collapse
|