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Lucia Helena O’dwyer - One of the best experts on this subject based on the ideXlab platform.
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Morphological, morphometric, and molecular characterization of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from naturally infected Caudisona durissa terrifica (Serpentes, Viperidae)
Parasitology Research, 2012Co-Authors: Tatiana Cristina Moço, Reinaldo José Silva, Newton Goulart Madeira, Karina Dos Santos Paduan, Adriano Stefani Rubini, Denise Dutra Menezes Leal, Lucia Helena O’dwyerAbstract:Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica , and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct Gamonts, while the other two had only one type of Gamont. The six distinct Gamonts were provisionally named Gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.
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Description of Gamontogonic and sporogonic stages of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from Caudisoma durissa terrifica (Serpentes, Viperidae)
Parasitology Research, 2011Co-Authors: Lucia Helena O’dwyer, Reinaldo José Silva, Newton Goulart MadeiraAbstract:Three specimens of Caudisoma durissa terrifica infected with Hepatozoon spp. were studied. One was parasitized by one type of Gamont and the other two were each infected by two morphologically different Gamonts. Utilizing morphology and morphometry analysis, we concluded that three types of Gamonts were very similar and may represent the same Hepatozoon species, but at least three different Hepatozoon species were infecting the C. durissa terrifica snakes in this study. Some of this species caused erythrocyte modifications. The sporogonic development of Hepatozoon sp. was observed from 12 h to the 20th day after female Culex quinquefasciatus blood meals.
Jerry F. Butler - One of the best experts on this subject based on the ideXlab platform.
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four additional hepatozoon species apicomplexa hepatozoidae from north florida ratsnakes genus pantherophis
Folia Parasitologica, 2012Co-Authors: Steven R. Telford, Paul E Moler, Jerry F. ButlerAbstract:Records from a colubrid host are reported for Hepatozoon horridus, described originally from a viperid snake. Hepatozoon horridus in Pantherophis guttatus (Colubridae) has Gamonts 14-18.0 by 4.0-5.5 µm, with length by width (LW) 60-99 µm2, and L/W ratio 2.5-3.9. Spherical to elongate, usually ovoid oocysts with L/W ratio 1.0-3.7 contain 16-160 spherical to usually ovoid sporocysts 15-31 by 14-26 µm, with L/W ratio 1.0-1.4, that contain 5-24 sporozoites. Two additional Hepatozoon species are described from ratsnakes in north Florida. Hepatozoon quadrivittata n. sp. from Pantherophis obsoletus quadrivittatus has Gamonts 12-17 by 4-6 µm, LW 56-102 µm2, and L/W ratio 2.6-3.8. Nearly spherical oocysts with L/W 1.0-1.1 contain 5-227 spherical to slightly ovoid sporocysts 20-48 by 19-45 µm, with L/W ratio 1.0-1.4, that contain 13-48 sporozoites. Hepatozoon spiloides n. sp. from Pantherophis obsoletus spiloides forms Gamonts 12-15 by 4-5 µm with LW 48-75 µm2 and L/W ratio 2.6-3.5. Occasionally rounded but usually elongate oocysts, with L/W ratio 1.0-2.7, contain 5-21 spherical to elongate sporocysts 28-43 by 18-35 µm, L/W ratio 2.5-3.9. In the distinctive Hepatozoon sp. present in Pantherophis obsoletus spiloides, Gamonts are 13-17 by 5-10 µm, with LW 75-140 µm2 and L/W ratio 1.4-3.0. Infected erythrocytes are always distorted and enlarged on average 2.5 times the size of uninfected cells, with nuclei enlarged by one-third and broadly elongated. Gamonts often stained deep blue, and cytoplasm of erythrocytes infected with mature Gamonts was always dehemoglobinized. Sporogony could not be obtained in three feedings by hundreds of Aedes aegypti, which usually died within the first 24-48 hr.
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Hepatozoon Species of the Timber Rattlesnake in Northern Florida: Description of a New Species, Evidence of Salivary Gland Oocysts, and a Natural Cross-Familial Transmission of an Hepatozoon Species
The Journal of parasitology, 2008Co-Authors: Sam R. Telford, Paul E Moler, Jerry F. ButlerAbstract:Two species of Hepatozoon, i.e., H. sauritus and H. horridus n. sp., were present in 1 of 8 timber rattlesnakes, Crotalus horridus. The narrow Gamonts of H. sauritus are 15.0–19.0 × 3.5–5.0 μm, with LW 58–86 μm2 and L/W 3.2–4.7, with a narrow, rounded anterior end. The spherical to slightly ovoid oocysts produce ovoid to elongate sporocysts, 21–43 × 12–24 μm, L/W 1.20–2.7, containing on average 22.1 (10–34) sporozoites. This is the first report of a natural cross-familial transfer of a Hepatozoon species. Gamonts of H. horridus n. sp. are 13.0–17.0 × 4.0–6.0 μm, with LW 63–102 μm2 and L/W 2.6–4.0, and have broadly rounded ends. The Gamont cytoplasm is vacuolated. The spherical to ovoid oocysts form spherical to elongate sporocysts 14–45 × 11–25 μm, L/W 1.0–2.3, producing an average of 13.0 (8–21) sporozoites. The salivary gland in 1 of 5 mosquitoes dissected contained 1 mature oocyst.
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TWO ADDITIONAL HEPATOZOON SPECIES (APICOMPLEXA: HEPATOZOIDAE) FROM THE SOUTHERN BLACK RACER, COLUBER CONSTRICTOR PRIAPUS (SERPENTES: COLUBRIDAE), IN NORTHERN FLORIDA
The Journal of parasitology, 2005Co-Authors: Sam R. Telford, Jerry F. Butler, Paul E MolerAbstract:Hepatozoon priapus n. sp. from Coluber constrictor priapus has robust Gamonts with broadly rounded ends, 18.0 x 4.2 microm (17.0-20.0 x 3.5-6.0), with LW 76.4 microm2 (59-105) and L/W 4.31 (2.9-5.4). The nucleus is always present in second quarter of Gamont, seldom extend into first quarter but often into third quarter, 6.0 x 3.0 (5.0-7.0 x 2.5-4.0), with LW 17.9 (13.7-21.0). Erythrocyte cytoplasm is always thin, appearing dehemoglobinized, with infected cells always distorted. Infected erythrocytes are much longer and wider than uninfected cells, with longer nuclei. Oocysts are spherical to ovoid, 92.5 x 86.0 (55-123 x 47-115) and L/W 1.08 (1.0-1.3), contain 14.0 (6-31) sporocysts. Sporocysts, which are also spherical to ovoid, 26.3 x 23.3 (19-50 x 16-38), LW 641.2 (320-1,500) and L/W 1.13 (1.0-2.2), contain 12.6 (5-18) sporozoites. Hepatozoon confusus n. sp., also from C. constrictor priapus, has slender Gamonts with rounded ends, 15.6 x 4.1 (14.0-17.0 x 3.5-5.0), with LW 64.3 (52-80) and L/W 3.82 (2.8-4.4). The nucleus is always present in second quarter of Gamont, commonly extending into first and third quarters, 5.0 x 2.7 (2.5-4.4 x 4.0-6.0), with LW 13.5 (11.0-16.5). Erythrocyte cytoplasm is sometimes thin, appearing partially dehemoglobinized, with infected cells usually distorted. Infected erythrocytes are longer than uninfected cells but similar in width, with erythrocyte nuclei longer. Oocysts are spherical to ovoid, 115.5 x 108.9 (52-278 x 50-278), with L/W 1.06 (1.0-1.2), and contain 25.0 (7-111) sporocysts. Sporocysts are spherical to ovoid, 27.6 x 25.2 (21-38 x 20-33), LW 701.3 (420-1,125) and L/W 1.09 (1.0-1.4), containing 20.2 (12-32) sporozoites.
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Susceptibility of Aedes aegypti and Aedes albopictus larvae to Ascogregarina culicis and Ascogregarina taiwanensis (Apicomplexa: Lecudinidae) from Florida
Journal of invertebrate pathology, 2003Co-Authors: Filiberto Reyes-villanueva, James J. Becnel, Jerry F. ButlerAbstract:The susceptibility of Aedes aegypti to Ascogregarina culicis and Aedes albopictus to Ascogregarina taiwanensis was examined with mosquito and parasite strains from Tampa, FL. When each host was bioassayed with its natural gregarine, the infection intensity indicated that Ae. aegypti was 59% more susceptible to A. culicis (87 Gamonts/larva) than Ae. albopictus to A. taiwanensis (47 Gamonts/larva). Infections in single and mixed host populations exposed to 100 oocysts/larva of one and both parasites demonstrated that Ae. aegypti harbors higher A. culicis Gamont loads than Ae. albopictus of A. taiwanensis. In dual gregarine exposures of single host populations, the A. culicis infection intensity in Ae. aegypti was reduced by approximately 50%. A. taiwanensis exhibited the same capability of infecting Ae. albopictus in single and dual exposures. In mixed host populations there were no cross infections, but A. taiwanensis in Ae. albopictus produced an infection intensity of approximately 70% lower than that of A. culicis in Ae. aegypti.
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hepatozoon species apicomplexa hepatozoidae of the corn snake elaphe guttata serpentes colubridae and the pigmy rattlesnake sistrurus miliarius barbouri serpentes viperidae in south florida
Journal of Parasitology, 2002Co-Authors: Steven R. Telford, Jerry F. Butler, Randy S TelfordAbstract:Hepatozoon guttata n. sp. is described from the corn snake (Elaphe guttata guttata) from south Florida. Gamonts average 14.6 × 4.6 (13–17 × 3.5–6) and are not recurved, with nucleus situated in the second quarter of the Gamont. Erythrocyte cytoplasm rarely appears partially dehemoglobinized. The infected cells are usually distorted and are longer than the uninfected erythrocytes but do not differ in width; nuclei are smaller in length and width than those of uninfected cells. Sporogony in Aedes aegypti occurs within the head and the thorax but rarely in the abdomen. Oocysts are spherical to usually ovoid, 87.2 × 75.9 (45–155 × 40–152.5) and contain on average 7.1 (2–32) sporocysts. Sporocysts are spherical to ovoid, 34.8 × 31.0 (20–55 × 17.5–47.5), with 45.7 (14–89) sporozoites contained within. The pigmy rattlesnake (Sistrurus miliarius barbouri) in south Florida is parasitized by H. sistruri n. sp. Gamonts average 14.1 × 5.6 (12.6–15.8 × 4.7–6.3) in breadth and are not recurved, with the nucleus always ...
Newton Goulart Madeira - One of the best experts on this subject based on the ideXlab platform.
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Morphological, morphometric, and molecular characterization of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from naturally infected Caudisona durissa terrifica (Serpentes, Viperidae)
Parasitology Research, 2012Co-Authors: Tatiana Cristina Moço, Reinaldo José Silva, Newton Goulart Madeira, Karina Dos Santos Paduan, Adriano Stefani Rubini, Denise Dutra Menezes Leal, Lucia Helena O’dwyerAbstract:Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica , and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct Gamonts, while the other two had only one type of Gamont. The six distinct Gamonts were provisionally named Gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.
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Description of Gamontogonic and sporogonic stages of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from Caudisoma durissa terrifica (Serpentes, Viperidae)
Parasitology Research, 2011Co-Authors: Lucia Helena O’dwyer, Reinaldo José Silva, Newton Goulart MadeiraAbstract:Three specimens of Caudisoma durissa terrifica infected with Hepatozoon spp. were studied. One was parasitized by one type of Gamont and the other two were each infected by two morphologically different Gamonts. Utilizing morphology and morphometry analysis, we concluded that three types of Gamonts were very similar and may represent the same Hepatozoon species, but at least three different Hepatozoon species were infecting the C. durissa terrifica snakes in this study. Some of this species caused erythrocyte modifications. The sporogonic development of Hepatozoon sp. was observed from 12 h to the 20th day after female Culex quinquefasciatus blood meals.
Reinaldo José Silva - One of the best experts on this subject based on the ideXlab platform.
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description of three new species of hepatozoon apicomplexa hepatozoidae from rattlesnakes crotalus durissus terrificus based on molecular morphometric and morphologic characters
Experimental Parasitology, 2013Co-Authors: Lucia Helena Odwyer, Reinaldo José Silva, Tatiana Cristina Moço, Karina Dos Santos Paduan, Carine Spenassatto, Paulo Eduardo Martins RibollaAbstract:Hepatozoon spp. are commonly found infecting snakes. Since the latter are parasitized by diverse forms and data in the literature show divergence, we studied Hepatozoon spp. diversity on Crotalus durissus terrificus snakes using both molecular and morphological approaches. Naturally infected animals were employed. Blood was collected, blood smears were prepared and an aliquot was stored at -20°C for DNA extraction. Five specimens of C. durissus terrificus were selected, each of them infected with one Gamont type. Morphological and morphometric analyses of the found Gamonts led to their grouping into three populations. For molecular characterization, seven oligonucleotide pairs that amplify distinct regions of rDNA gene were tested by adopting the PCR technique. Only the oligonucleotide pairs HepF300/Hep900 and HEMO1/HEMO2 were efficient in amplifying and distinguishing different isolates of Hepatozoon spp. from snakes. The better results were obtained when both oligonucleotide pairs were used in association. Based on the molecular and morphologic differences, three new species were proposed: Hepatozoon cuestensis sp. nov.; Hepatozoon cevapii sp. nov. and Hepatozoon massardii sp. nov. This is the first description of new Hepatozoon species from snakes, based on molecular characterization and morphological data, in South America.
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Morphological, morphometric, and molecular characterization of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from naturally infected Caudisona durissa terrifica (Serpentes, Viperidae)
Parasitology Research, 2012Co-Authors: Tatiana Cristina Moço, Reinaldo José Silva, Newton Goulart Madeira, Karina Dos Santos Paduan, Adriano Stefani Rubini, Denise Dutra Menezes Leal, Lucia Helena O’dwyerAbstract:Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica , and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct Gamonts, while the other two had only one type of Gamont. The six distinct Gamonts were provisionally named Gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.
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Description of Gamontogonic and sporogonic stages of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from Caudisoma durissa terrifica (Serpentes, Viperidae)
Parasitology Research, 2011Co-Authors: Lucia Helena O’dwyer, Reinaldo José Silva, Newton Goulart MadeiraAbstract:Three specimens of Caudisoma durissa terrifica infected with Hepatozoon spp. were studied. One was parasitized by one type of Gamont and the other two were each infected by two morphologically different Gamonts. Utilizing morphology and morphometry analysis, we concluded that three types of Gamonts were very similar and may represent the same Hepatozoon species, but at least three different Hepatozoon species were infecting the C. durissa terrifica snakes in this study. Some of this species caused erythrocyte modifications. The sporogonic development of Hepatozoon sp. was observed from 12 h to the 20th day after female Culex quinquefasciatus blood meals.
Stephen C. Landers - One of the best experts on this subject based on the ideXlab platform.
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the fine structure of the Gamont of pterospora floridiensis apicomplexa eugregarinida
Journal of Eukaryotic Microbiology, 2002Co-Authors: Stephen C. LandersAbstract:Abstract Transmission electron microscopy of the Gamont stage of Pterospora floridiensis has revealed a number of features. The Gamont's surface varies from smooth to crenulate, with numerous pockets and folds. The pellicle is composed of an outer membrane, a middle lucent region, and an inner dense layer comprised of two tightly appressed membranes. Short ridges on the pellicle are 200—300+ nm long, 75–100 nm wide, and have a height of ∼ 50 nm. The thickness of the pellicle is 100 nm when measured from the inner membrane to the top of a ridge. The ridges are formed by the plasma membrane and an underlying structure that is circular in cross-section. The surface folds and the pellicular ridges are distributed over the soma and the cell's unusual branching arms, though both are reduced near the junction between two Gamonts in syzygy, and are absent at the central area of the junctional site. The cell has numerous active Golgi complexes associated with vesicles, as well as scattered dense mitochondria, lipi...
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The fine structure of the Gamont of Pterospora floridiensis (Apicomplexa: Eugregarinida).
The Journal of eukaryotic microbiology, 2002Co-Authors: Stephen C. LandersAbstract:Transmission electron microscopy of the Gamont stage of Pterospora floridiensis has revealed a number of features. The Gamont's surface varies from smooth to crenulate, with numerous pockets and folds. The pellicle is composed of an outer membrane, a middle lucent region, and an inner dense layer comprised of two tightly appressed membranes. Short ridges on the pellicle are 200-300+ nm long, 75-100 nm wide, and have a height of approximately 50 nm. The thickness of the pellicle is 100 nm when measured from the inner membrane to the top of a ridge. The ridges are formed by the plasma membrane and an underlying structure that is circular in cross-section. The surface folds and the pellicular ridges are distributed over the soma and the cell's unusual branching arms, though both are reduced near the junction between two Gamonts in syzygy, and are absent at the central area of the junctional site. The cell has numerous active Golgi complexes associated with vesicles, as well as scattered dense mitochondria, lipid droplets, and paraglycogen granules. The nucleus has a large (13 microm) endosome, eccentrically located, and peripheral chromatin along the inner nuclear membrane.
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Pterospora floridiensis, a new species of acephaline gregarine (Apicomplexa) from the maldanid polychaete Axiothella mucosa in St. Andrew Bay, Florida
Systematic Parasitology, 2001Co-Authors: Stephen C. LandersAbstract:Pterospora floridiensis , a new species of acephaline gregarine from the body cavity of the bamboo worm Axiothella mucosa (Polychaeta: Maldanidae), is described. The Gamont stage is distinctive and possesses a central cytoplasmic mass and two elongate trunks that bifurcate repeatedly and comprise approximately 60% of the total cell length. The Gamont averages 198 (50–545) × 71 (25–180) μm (N= 45, 43) from the tip of the trunks to the anterior (the junctional site with the other Gamont in syzygy). Gametocysts average 402 (297–545) × 304 (149–495) μm (N= 37). The oöcysts measure 22.5 (20.5–23.5) × 8.3 (7.0–10.0) μm (N= 30) and possess an internal capsule (average length = 13.9 μm, N= 30) containing the sporozoites and aliform wings on the epispore.
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Ultrastructural Analysis Of The Aseptate Gregarine Pterospora, A Parasite of The Bamboo Worm Axiothella Mucosa.
Microscopy and Microanalysis, 1999Co-Authors: Stephen C. LandersAbstract:The gregarine Pterospora is a parasite found in the body cavities of bamboo worms (Polychaeta: Maldanidae). The Gamont stage of Pterospora has a bizarre structure with a main cell body and multiple posterior cytoplasmic extensions (Fig. 1). The cells are found in pairs within the coelom of the host and move by cytoplasmic streaming as they fill and empty their posterior extensions. Reports of this parasite in the literature are few (see references 1 & 2 for a review) and no ultrastructural details have been published regarding the genus. This study examines the fine structure of the Gamont stage with particular emphasis on the structure of the pellicle.The maldanid worm Axiothella mucosa was collected by shovel in St. Andrew Bay, Florida and returned to the Troy State University campus. Pterospora spp. Gamonts were pipetted from minced setigers of the worms and fixed in 3% glutaraldehyde buffered with 0.05M sodium cacodylate, pH 7.5, for 1-6 hours.
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Pterospora demodendrion sp.nov. and Pterospora clymenellae, acephaline eugregarines from coastal North Carolina.
European journal of protistology, 1991Co-Authors: Stephen C. LandersAbstract:Pterospora demodendrion sp.nov., an acephaline eugregarine (Eugregarinorida, Urosporidae) from the coelom of Axiothella mucosa (Polychaeta, Maldanidae) is described. The Gamont averages 277 × 139 μm and possesses 20-36 posterior prolongations. Gametocysts average 412 × 287 μm; without polar funneled openings. Oocysts average 24.4 × 8.4 μm; with aliform wings on the epispore wall and containing a lemon-shaped (16.2 × 7.8 μm) inner capsule. This species is most similar to P. ramificata, though significantly distinct in characteristics of the Gamont and gametocyst. Pterospora clymenellae is also reported herein, from the maldanid Clymenella torquata, and shown to lack the epispore wings present in other Pterospora species.
