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Journal of Invertebrate Pathology Jul 1976
Topics: Aedes; Animals; Eukaryota
PubMed: 932479
DOI: 10.1016/0022-2011(76)90076-8 -
International Journal For Parasitology Feb 2003Structural diversity of fish microsporidian life cycle stages and of the host-parasite interface is reviewed. In the infected cell of the fish host, microsporidia may... (Review)
Review
Structural diversity of fish microsporidian life cycle stages and of the host-parasite interface is reviewed. In the infected cell of the fish host, microsporidia may either cause serious degradation of the cytoplasm and demise of the cell, or they may elicit host cell hypertrophy, producing a parasite-hypertrophic host cell complex, the xenoma. The structure of the xenoma and of its cell wall may differ according to the genus of the parasite, and seems to express properties of the parasite rather than those of the host. In merogony, the parasite cell surface interacts with the host cell in diverse ways, the most conspicuous being the production of thick envelopes of different types. Sporogony stages reveal different types of walls or membranes encasing the sporoblasts and later the spores and these envelopes may be of host or parasite origin. Nucleospora differs from all other fish microsporidia by its unique process of sporogony. Except for the formation of conspicuous xenomas, there are no essentially different structures in fish-infecting microsporidia compared with microsporidia from other hosts. Although the structures associated with the development of fish microsporidia cannot be attributed importance in tracing the phylogeny, they are relevant for practical determination and assessing the relation to the host. The possibility of the existence of an intermediate host is discussed. Higher-level classification of Microsporidia is briefly discussed and structure and evolutionary rates in microsporidian rDNA are reviewed. Discussion of rDNA molecular phylogeny of fish-infecting microsporidia is followed by classification of these parasites. Most form a rather cohesive clade. Outside this clade is the genus Nucleospora, separated at least at the level of Order. Within the main clade, however, there are six species infecting hosts other than fish. Based on data available for analysis, a tentative classification of fish-infecting microsporidia into five groups is proposed. Morphologically defined groups represent families, others are referred to as clades. Group 1, represented by family Pleistophoridae, includes Pleistophora, Ovipleistophora and Heterosporis; Vavraia and Trachipleistophora infect non-fish hosts. Group 2, represented by family Glugeidae, is restricted to genus Glugea and Tuzetia weidneri from crustaceans. Group 3 comprises three clades: Loma and a hyperparasitic microsporidian from a myxosporean; Ichthyosporidium and Pseudoloma clade and the Loma acerinae clade. For the latter species a new genus has to be established. Group 4 contains two families, Spragueidae with the genus Spraguea and Tetramicridae with genera Microgemma and Tetramicra, and the Kabatana and Microsporidium seriolae clade. Group 5 is represented by the family Enterocytozoonidae with the genus Nucleospora and mammal-infecting genus Enterocytozoon.
Topics: Animals; DNA, Ribosomal; Fishes; Life Cycle Stages; Microsporidia; Oligonucleotide Array Sequence Analysis; Phylogeny
PubMed: 12633649
DOI: 10.1016/s0020-7519(02)00252-7 -
Boletin Chileno de Parasitologia 1988
Topics: Animals; Chile; Fish Diseases; Gills; Protozoan Infections, Animal; Salmon
PubMed: 3269733
DOI: No ID Found -
The Journal of Eukaryotic Microbiology 2001Molecular data have proved useful as an alternative to morphological data in showing the relationships of genera within the phylum Microsporidia, but until now have been...
Molecular data have proved useful as an alternative to morphological data in showing the relationships of genera within the phylum Microsporidia, but until now have been available only for ribosomal genes. In previous studies protein-coding genes of microsporidia have been used only to assess their position in the evolution of eukaryotes. For the first time we report on the use of a protein-coding gene, the A-G region of the largest subunit of RNA polymerase II (RPB1) from 14 mainly polysporous species, to generate an alternative phylogeny for microsporidia. Using the amino acid sequences, the genera and species fell into the same main groupings as had been obtained with 16S rDNA sequences, but the RPB1 data provided better resolution within these groups. The results supported the pairings of Trachipleistophora hominis with Vavraia culicis and Pleistophora hippoglossoideos with Pleistophora typicalis. They also confirmed that the genus Pleistophora is not monophyletic and that it will be necessary to transfer Pleistophora ovariae and Pleistophora mirandellae into one or more other genera, as has already been effected for Pleistophora anguillarum.
Topics: Animals; DNA, Protozoan; Fishes; Humans; Insecta; Microsporidia; Microsporidiosis; Molecular Sequence Data; Phylogeny; RNA Polymerase II; Sequence Analysis, DNA
PubMed: 11249186
DOI: 10.1111/j.1550-7408.2001.tb00422.x -
The Journal of Eukaryotic Microbiology 1994In conclusion, at the current time the most important task of the laboratory for proper clinical management of the patient with microsporidiosis is to perform... (Review)
Review
In conclusion, at the current time the most important task of the laboratory for proper clinical management of the patient with microsporidiosis is to perform genus-level diagnosis of the agent, i.e. distinguishing Encephalitozoon sp. infection from other microsporidial agents including Septata, Enterocytozoon, Nosema, and Pleistophora. This can be performed in any well-equipped pathology department with access to electron microscopy. If species identification is desired, we currently recommend consultation with one of several laboratories specializing in this area until diagnostic reagents become more widely available.
Topics: AIDS-Related Opportunistic Infections; Encephalitozoonosis; Eye Infections, Parasitic; Female; Humans; Male; Prostatitis; Respiratory Tract Infections; Urinary Tract Infections
PubMed: 7804259
DOI: No ID Found -
Archives of Pathology & Laboratory... Feb 1996Microsporidiosis is a group of rapidly emerging protozoan infections that have thus far been reported predominantly from severely immunosuppressed persons with the... (Review)
Review
OBJECTIVE
Microsporidiosis is a group of rapidly emerging protozoan infections that have thus far been reported predominantly from severely immunosuppressed persons with the acquired immunodeficiency syndrome (AIDS). The four genera that have been identified in AIDS patients (Enterocytozoon, Encephalitozoon, Septata, and Pleistophora) are an increasingly common source of both localized and disseminated infections. However, the clinical and pathologic features of these agents are being described with such rapidity that many pathologists are unaware of the histologic, immunologic, and molecular methods for diagnosing these infections. This article summarizes the clinical and morphologic spectrum of the microsporidian species that infect patients with AIDS. Additionally, the role of ultrastructural, immunologic, tissue culture, and molecular techniques for the diagnosis of microsporidian infections are discussed.
DATA SOURCES
Clinical and pathologic findings were obtained from patients with AIDS who were evaluated for microsporidian infections at the Grady Memorial Hospital in Atlanta. Selected laboratory studies were performed at the Division of Parasitic Diseases of the Centers for Disease Control and Prevention and at the Department of Physiology at Morehouse University. Additionally, some cases were sent for consultation to the Infectious Disease Pathology service at Emory University. These data were combined with the published studies of microsporidian infection from the medical literature.
DATA SYNTHESIS
The pathologic appearance of microsporidian infections in each major organ system (ocular, respiratory, genitourinary, gastrointestinal) is illustrated using routine and special histochemistry and immunofluorescence. The differential diagnostic features of the four genera of microsporidia infecting AIDS patients are illustrated using transmission and scanning electron micrographs from biopsy, autopsy, and tissue culture materials. Cytologic evaluation of body tissues is emphasized as a sensitive method for microsporidian diagnosis.
CONCLUSIONS
Microsporidian infections can be expected to remain an increasingly important cause of morbidity and mortality in patients with AIDS. It is important that pathologists and microbiologists become acquainted with the clinicopathologic spectrum of these emerging protozoal infections, ensuring timely diagnosis and subsequent treatment.
Topics: Acquired Immunodeficiency Syndrome; Animals; Fluorescent Antibody Technique; Humans; Microscopy, Electron, Scanning; Microsporida; Polymerase Chain Reaction; Protozoan Infections
PubMed: 8712897
DOI: No ID Found -
Journal of Invertebrate Pathology Mar 1974
Topics: Animals; Apicomplexa; Decapoda; Spores
PubMed: 4207629
DOI: 10.1016/0022-2011(74)90178-5 -
Parazitologiia 1980The microsporidian Pleistophora carpocapsae does not influence the growth, development and mortality of its host--the caterpiller Malacosoma neustria L. On the other... (Comparative Study)
Comparative Study
The microsporidian Pleistophora carpocapsae does not influence the growth, development and mortality of its host--the caterpiller Malacosoma neustria L. On the other hand P. schubergi causes sireous desturbances of the insects functions: stimulation of growth just after the infection, its opression and retardation of development during the next stage of the disease. All this results in the fatal end.
Topics: Animals; Apicomplexa; Body Weight; Insecta
PubMed: 6769082
DOI: No ID Found -
The Journal of Parasitology Dec 1980
Comparative Study
Topics: Animals; Cytological Techniques; Eukaryota; Methods; Spores
PubMed: 7012293
DOI: No ID Found -
The Journal of Protozoology Nov 1968
Topics: Animals; Eukaryota; Fishes; Microscopy; Microscopy, Electron; Spores
PubMed: 5752777
DOI: 10.1111/j.1550-7408.1968.tb02190.x