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1.
J Helminthol ; 95: e27, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34030754

RESUMEN

A number of variable descriptive accounts of Aspersentis megarhynchus (von Linstow, 1892) Golvan, 1960 have been reported from specimens collected from many species of fish in various locations off Antarctic islands. We have described a new population from Notothenia coriiceps Richardson (Nototheniidae) off Galindez Island, West Antarctica, and features not previously reported, resolved the taxonomic controversies and nomenclature, and emended and updated the generic diagnosis taking into account the newly observed structures. These are depicted in microscopic images and include the outer spiral wall of the proboscis receptacle, the thicker dorsal wall of the receptacle compared to the ventral wall, parts of the female reproductive system, the separate cement gland ducts, the dorsal position of the male gonopore and more detail of proboscis hooks and trunk spines. It is surprising that the newly observed features were missed from the many descriptions of A. megarhynchus created since the original description. The variability in A. megarhynchus is noted with a comparison of the morphometrics of our specimens vs. those in six other descriptions. We also analysed the metal composition of hooks and spines using energy-dispersive X-ray analysis and concluded a molecular characterization of the species based on 18S DNA gene, with related phylogenetic analyses.


Asunto(s)
Acantocéfalos , Enfermedades de los Peces , Helmintiasis Animal , Acantocéfalos/anatomía & histología , Acantocéfalos/clasificación , Animales , Regiones Antárticas , Femenino , Enfermedades de los Peces/parasitología , Masculino , Filogenia
2.
Acta Parasitol ; 66(3): 863-870, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33609238

RESUMEN

PURPOSE: The purpose of the present study was to provide molecular support for the validity of the morphological description of Acanthosentis kashmirensis Amin, Heckmann, Zargar, 2017 which was originally poorly described as Neoechinorhynchus kashmirensis Fotedar and Dar, 1977 from the Indian subcontinent, and to characterise its molecular identity and phylogenetic relationships. METHODS: Total DNA was extracted, and the partial region of the small subunit (SSU) 18S rDNA and ITS-rDNA genes were amplified and sequenced. Genetic diversity was calculated and phylogenetic analysis of the nucleotide sequence data was performed. RESULTS: In this study, the molecular profile of this acanthocephalan was generated for the first time. Based on the partial 18S rDNA, interspecific variation between A. kashmirensis with different species of Acanthosentis and were 3.6-10.3% and 22.4-38.2% based on 18S rDNA and ITS-rDNA genes, respectively. We described the phylogenetic relationships of A. kashmirensis compared with other species of the genus and also with members of the family Quadrigyridae. CONCLUSIONS: The ITS-rDNA sequences of members of the family Quadrigyridae are more variable than 18S rDNA that can be useful for achieving a proper assessment of biodiversity. Sequence data generation from additional species of Acanthosentis will be needed to reconstruct the phylogenetic relationships of this group of acanthocephalans.


Asunto(s)
Acantocéfalos , Acantocéfalos/genética , Animales , ADN Ribosómico/genética , Filogenia , ARN Ribosómico 18S/genética
3.
J Helminthol ; 95: e3, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33504379

RESUMEN

Pallisentis (Pallisentis) nandai Sarkar, 1953 is a freshwater fish parasite restricted to the Indian subcontinent in the Ganga River and its tributaries. It was described from the leaffish, Nandus nandus (Hamilton) from the Ganga River delta at Calcutta. We recovered variant specimens from the same host species from the Ganga near its headwaters at Bijnor about 1500 km away. Our specimens were clearly identifiable as P. nandai but varied considerably from those in the original description, especially in the size of proboscis hooks, receptacle and lemnisci. The original description was incomplete (missing line drawings of female trunk and reproductive system, male trunk, complete proboscis, hooks and hook roots) and inaccurate (proboscis, hooks, receptacle wall), and some measurements were lumped together for both sexes. We provide a complete description and include new morphological information including the first description of para-receptacle structure in the genus Pallisentis Van Cleave, 1928, scanning electron microscopy and microscope images, molecular analysis, and energy dispersive X-ray analysis (EDXA) of hooks and spines of our specimens for the first time. Additional details of proboscis hook roots, trunk spines, micropores and micropore distribution are described. The unique metal composition of hooks (EDXA) demonstrated a considerably high but variable level of sulphur and negligible level of calcium in collar and trunk spines and hook tips, but a higher level of sulphur and calcium at the hook basal arch than at the hook tip and edge. A comparison with the EDXA pattern of another species of Pallisentis, P. Indica Mital & Lal, 1976, were considerably different. The phylogenetic position of P. nandai within Eoacanthocephala was generated to assess the molecular characterization based on 18S and ITS1-5.8S-ITS2 ribosomal DNA sequences. Maximum likelihood and Bayesian inference analyses placed P. nandai in a clade with other Pallisentis species under the family Quadrigyridae. This is the first report based on molecular evidence for P. nandai.


Asunto(s)
Acantocéfalos , Enfermedades de los Peces , Helmintiasis Animal , Acantocéfalos/clasificación , Animales , Teorema de Bayes , Femenino , Enfermedades de los Peces/parasitología , Helmintiasis Animal/parasitología , India , Masculino , Microscopía Electrónica de Rastreo , Filogenia
4.
J Helminthol ; 94: e207, 2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33118894

RESUMEN

Centrorhynchus globocaudatus (Zeder, 1800) Lühe, 1911 (Centrorhynchidae) was reported in birds of prey. Our population from Falco tinnunculus Linnaeus (Falconidae) and Buteo buteo Linnaeus (Accipitridae) in northern Italy was morphologically distinct from others described elsewhere. The worms are elongate and cylindrical. Proboscis long, apically truncated and bare, with wider base and variably faint constriction at point of attachment of receptacle. Large anterior hooks well rooted; posterior spiniform hooks with reduced roots; transitional hooks with scutiform roots in-between. Four tubular cement glands extend into prominent ducts overlapping a large Saefftigen's pouch. Bursa large, with sensory plates. Vagina with laterally slit orifice in sub-ventral pit of globular terminal extension. Thick-shelled eggs ovoid without polar prolongation of fertilization membrane. In our specimens, proboscis hooks, receptacle, male reproductive system, and lemnisci especially in males varied in size from those from Ukraine, India, Egypt, Kyrgystan, Russia, Georgia, Armenia and Asian Soviet Republics. Our description of the Italian specimens includes new morphological information supported by scanning electron microscopy and microscope images, molecular analysis and energy dispersive X-ray analysis (EDXA) of hooks. Additional new details of proboscis hook roots, micropores and micropore distribution are described. Metal composition of hooks (EDXA) demonstrated high levels of calcium and phosphorous, and high levels of sulphur in core and cortical layers of eggs. The molecular profile based on sequences of 18S and cytochrome c oxidase 1 genes is also provided, as well as phylogenetic reconstructions including all available sequences of the family Centrorhynchidae, although further sequences are needed in order to clarify their phylogenetic relationships.


Asunto(s)
Acantocéfalos , Falconiformes/parasitología , Rapaces/parasitología , Acantocéfalos/anatomía & histología , Acantocéfalos/clasificación , Acantocéfalos/genética , Acantocéfalos/aislamiento & purificación , Animales , Complejo IV de Transporte de Electrones/genética , Genes de Helminto , Helmintiasis Animal , Italia/epidemiología , Filogenia , Prevalencia , ARN Ribosómico 18S/genética
5.
J Helminthol ; 94: e133, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32114988

RESUMEN

We describe morphological features not previously reported for this old acanthocephalan Nephridiacanthus major (Bremser, 1811 in Westrumb, 1821) Golvan, 1962 first described over 200 years ago. Our specimens were collected from long-eared hedgehog Hemiechinus auritus (Gmelin, 1770) (Erinaceidae) in Iran. We compare the morphometrics of our material with others previously reported from the same host in Iran, Russia, central Asia and Europe. Our specimens had markedly smaller proboscides, proboscis hooks and lemnisci than those reported from Russia and central Asia, but comparable measurements of other structures with specimens previously described from other collections. We document our new observations with scanning electron microscopy features not previously demonstrable by other observers and provide a chemical analysis of proboscis hooks using energy-dispersive X-ray analysis for the first time. The molecular profile of this acanthocephalan, based on 18S rDNA and cox1 genes, was generated for the first time. The phylogenetic analysis showed that N. major is placed in a clade of the family Oligacanthorhynchidae, well separated from the families Moniliformidae and Gigantorhynchidae.


Asunto(s)
Acantocéfalos/clasificación , Acantocéfalos/ultraestructura , Erizos/parasitología , Filogenia , Animales , ADN Ribosómico/genética , Femenino , Helmintiasis Animal , Irán , Masculino , Microscopía Electrónica de Rastreo
6.
Helminthologia ; 57(1): 1-11, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32063734

RESUMEN

Paratrajectura longcementglandatus Amin, Heckmann et Ali, 2018 (Transvenidae) was recently described from two species of percid fishes collected from the marine territorial waters of Iraq and Iran in the Persian Gulf. The genus Paratrajectura Amin, Heckmann et Ali, 2018 is a close relative to transvenid genera Trajectura Pichelin et Crib, 2001 and Transvena Pichelin et Crib, 2001. Morphologically, Paratrajectura is characterised by having apical proboscis cone, long, tubular cement glands, short lemnisci, prominent roots on all proboscis hooks, subterminal female gonopore, and males with long pre-equatorial testes. Molecular studies of P. longcementglandatus using 18S rDNA and cox1 genes compared with available data of members of other families of Echinorhynchida showed that P. longcementglandatus is grouped with species of the genus Transvena forming a clade within the family Transvenidae.

7.
Helminthologia ; 56(1): 11-21, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31662668

RESUMEN

New morphometric data, including details of the copulatory system and attachment structures, as well as inner organs are provided for Ancyrocephalus paradoxus Creplin, 1839. Scanning electron microscopy reveals new information of the body shape, position of the cephalic organs' openings, and structure of anchors, as well as differences in the in anchors' structure in adults and sub-adults of A. paradoxus. Energy dispersive analysis for X-ray was conducted for the first time for anchors in Monogenea and revealed structural differences between different parts of the anchors in two age groups.

8.
Parasite ; 19(3): 267-70, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22910669

RESUMEN

Neoechinorhynchus manubrianus Amin, Ha & Ha, 2011 (Acanthocephala: Neoechinorhynchidae) (formerly Neoechinorhynchus manubriensis Amin, Ha & Ha, 2011), was recently described based on optical microscopy of four males and two females (none was gravid) from caroun croaker, Johnius carouna (Cuvier), flower croaker, Nibea albiflora (Richardson), and silver croaker, Pennabia argentata (Houttuyen) (Sciaenidae) in Halong Bay, Vietnam. Subsequently, many more specimens became available from N. albiflora that were studied using SEM. SEM studies showed many additional features that were not possible to discern with optical microscopy. These included the prominent angulation of the anterior trunk, the presence of (1) anterio-dorsal and (2) undulating mid-lateral fin-like protrusions of the body wall, uniquely shaped eggs as well as details of trunk micropores, proboscis, bursa, and female gonopore. Microscopical examination of eggs from the new collection demonstrated the presence of polar prolongation of fertilization membrane which places N. manubriensis in the subgenus Hebesoma. The features of trunk angulation, trunk fins, and egg morphology further distinguish N. manubriensis from all other species of Neoechinorhynchus Stiles and Hassall, 1905 from Vietnam or from any where else in the world.


Asunto(s)
Acantocéfalos/ultraestructura , Enfermedades de los Peces/parasitología , Helmintiasis Animal/parasitología , Perciformes/parasitología , Acantocéfalos/clasificación , Animales , Femenino , Masculino , Microscopía Electrónica de Rastreo , Vietnam
9.
J Egypt Soc Parasitol ; 31(1): 281-94, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12557950

RESUMEN

For the fine structure of Gyliauchen volubilis, sections of the finger-like projections showed the structure of a segmented body, which is not attached with the outer membrane of the tegument. Each projection consists of one to four segments, the smallest segment is triangular in shape and located on the top of the projection, enveloped by a triple layered membrane, with electron dense structures in the cytoplasm. Two types of vesicles are scattered in the tegumental matrix; vesicle with electron dense body, and multigranulated vesicle. Spherical fragment also contains electron dense structures and starts as a round projection of the tegument that detaches itself from the rest of the tegument. The presence of these fragments could be evidence of exocytosis for this trematoda. A layer of vacuoles measuring 1 to 1.5 microm long and 0.5 to 0.8 microm wide, are located beneath the matrix of the tegument which could be the douse of release product. For some areas of trematode, larger vacuoles measure 2.6 to 4.3 microm long and 0.5 to 0.8 microm wide, are found near the tegumental surface but in small number. There are two layers of subtegumental myofibers, circular and longitudinal. The circular muscle myofibers are grouped in bundles whereas the longitudinal myofibers are densely distributed adjacent to the circular fibers. Numerous polygonal structures whose function has not yet been determined are located beneath the muscle layers.


Asunto(s)
Integumento Común/anatomía & histología , Trematodos/anatomía & histología , Trematodos/ultraestructura , Animales , Egipto , Enfermedades de los Peces/parasitología , Peces/parasitología , Océanos y Mares , Enfermedades Parasitarias en Animales/parasitología
10.
Gen Comp Endocrinol ; 118(2): 249-61, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10890565

RESUMEN

Interleukin-6 (IL-6) and tumor necrosis factor (TNF) are secreted and/or synthesized by the rat and human adrenal cortex. In this study, the release of IL-6 and TNF from bovine adrenal cells was determined. Bovine adrenal glands were collected from an abattoir and dissected into the zona glomerulosa (ZG), zona fasciculata (ZF), zona reticularis (ZR), and medulla. The tissues were enzymatically dispersed to single cells and cultured for 4-6 days. The cells were then exposed (4 h) to angiotensin II (AII), adrenocorticotrophic hormone (ACTH), phorbol dibutyrate (PDB), interleukin-1beta (IL-1beta), interleukin-1alpha (IL-1alpha), and endotoxin (LPS). The IL-6 and TNF content of the incubation medium was determined by bioassays. The release of IL-6 and TNF from the ZG, ZF, ZR, and medulla was increased by PDB, IL-1alpha, IL-1beta, and LPS. In contrast, ACTH and AII increased IL-6 release from the ZG, ZF, and ZR but had no effect on IL-6 release from the medulla. ACTH decreased TNF release from all adrenal cortical zones but had no effect on TNF release from the medulla. Immunohistochemistry utilizing antibodies against TNFalpha demonstrated TNFalpha-containing cells throughout the adrenal gland. The majority of the cells of the ZG, ZF, and ZR contained TNFalpha. However, the cells of the ZG contained more TNFalpha than the cells of the ZR or ZF. Small patches of TNFalpha-containing cells were also found in the adrenal medulla and capsule. These findings support the hypothesis that IL-6 and TNF may have autocrine/paracrine effects on the adrenal gland.


Asunto(s)
Glándulas Suprarrenales/metabolismo , Interleucina-6/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Médula Suprarrenal/efectos de los fármacos , Médula Suprarrenal/metabolismo , Hormona Adrenocorticotrópica/farmacología , Angiotensina II/farmacología , Animales , Bovinos , Células Cultivadas , Interleucina-1/farmacología , Lipopolisacáridos/farmacología , Forbol 12,13-Dibutirato/farmacología , Zona Fascicular/efectos de los fármacos , Zona Fascicular/metabolismo , Zona Glomerular/efectos de los fármacos , Zona Glomerular/metabolismo , Zona Reticular/efectos de los fármacos , Zona Reticular/metabolismo
11.
Endocrine ; 13(3): 369-77, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11216650

RESUMEN

Interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) are synthesized and released from adrenal cells. Therefore, the effects of TNF-alpha and IL-6 on cortisol release from bovine zona fasciculata (ZF) cells were investigated. IL-6 (10-1000 pg/mL) significantly increased basal and adrenocorticotropic hormone (ACTH)-stimulated cortisol release in a concentration-dependent manner. This stimulatory effect of IL-6 became apparent at intervals as short as 4 h and continued through 24 h. IL-6 also potentiated the cortisol release stimulated by the adenylyl cyclase activator forskolin. By contrast, TNF-alpha (0.1-10 ng) inhibited basal and ACTH-stimulated cortisol release in a concentration-dependent manner. The inhibitory effects of TNF-alpha on cortisol release were significant at time intervals as short as 4 h and continued through 24 h. TNF-alpha inhibited forskolin-stimulated cortisol release. Binding studies demonstrated that ZF cells have IL-6 receptors (100 receptors/cell, Kd of 7.5 x 10(-11)) and TNF receptors (200 receptors/cell, Kd of 2.4 x 10(-9) M). Immunohistochemical analysis provided evidence that the majority of ZF cells have IL-6 receptors, TNF type 1 receptors, and TNF type 2 receptors. Because IL-6 and TNF-alpha are released from the adrenal cortex and these cytokines modify the release of cortisol from the ZF, IL-6 and TNF-alpha may play a paracrine or autocrine role in the regulation of adrenal function.


Asunto(s)
Hidrocortisona/metabolismo , Interleucina-6/farmacología , Receptores de Interleucina-6/fisiología , Receptores del Factor de Necrosis Tumoral/fisiología , Factor de Necrosis Tumoral alfa/farmacología , Zona Fascicular/metabolismo , Adenilil Ciclasas/metabolismo , Hormona Adrenocorticotrópica/farmacología , Animales , Bovinos , Colforsina/farmacología , Sinergismo Farmacológico , Activación Enzimática/efectos de los fármacos , Inmunohistoquímica , Interleucina-6/metabolismo , Cinética , Receptores de Interleucina-6/análisis , Receptores del Factor de Necrosis Tumoral/análisis , Factor de Necrosis Tumoral alfa/metabolismo , Zona Fascicular/química
12.
J Egypt Soc Parasitol ; 29(3): 1017-30, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-12561938

RESUMEN

To determine the effect of S. mansoni and aflatoxin B1, 120 hamsters were divided into six groups of 20 each as follows: group I, S. mansoni only, group II, aflatoxin B1 only, group III, S. mansoni then aflatoxin B1 eight week, group IV, aflatoxin B1 then infected with S. mansoni six weeks, later, group V, aflatoxin B1 and S. mansoni simultaneously, group VI control. Loss of body, liver, and spleen weight was more prominent in groups IV and V than in other four groups. The higher mortality rate was in group III. Animals treated with aflatoxin followed by S. mansoni infection appeared to have a less deteriorating effect on the liver (group IV) than group III treated with by S. mansoni first followed by aflatoxin treatment. No morphological abnormalities were detected in the worms including testicular changes in males but a significant number of females was immature even in copula (P < 0.01) in groups III, IV, and V. The average number of S. mansoni eggs was less in groups III, IV, and V in comparison to group I. No abnormalities were detected in the eggs for groups infected with S. mansoni. The diameters of granulomas around eggs, were large on an average in groups III, IV and V as compared with groups I and II.


Asunto(s)
Aflatoxina B1/toxicidad , Aspergilosis/complicaciones , Schistosoma mansoni/patogenicidad , Esquistosomiasis mansoni/complicaciones , Animales , Aspergillus flavus/patogenicidad , Cricetinae , Hígado/parasitología , Hígado/patología , Mesocricetus , Recuento de Huevos de Parásitos , Esquistosomiasis mansoni/parasitología , Esquistosomiasis mansoni/fisiopatología
13.
Mutat Res ; 446(2): 181-8, 1999 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-10635340

RESUMEN

Aflatoxin B1 (AFB1) is classified as a Group I hepatocarcinogen in humans by the International Agency for Research on Cancer (IARC). The alkaline Comet assay is a simple and rapid method by which DNA damage can be demonstrated as a function of tail moment. The present work is the first to evaluate the genotoxicity of AFB1 in fish using the Comet assay. Two different species of fish were selected as models due to previously established sensitivity to AFB1: rainbow trout (sensitive) and channel catfish (resistant). Fish were i.p. injected with 0.5 mg AFB1/1 ml DMSO/1 kg body weight. The Comet assay was performed after 4 and 24 h on whole blood, liver, and kidney cells of both species. Trout blood and kidney tissue tested displayed significant (p < 0.05) and extensive DNA damage (shown by increased tail moment) after 4 h which then decreased by 24 h. In liver cells, damage progressively increased over time. Conversely, similarly treated catfish showed no elevation in DNA damage over controls at the same doses. These results suggest that the Comet assay is a useful tool for monitoring the genotoxicity of mycotoxins such as AFB1 and for evaluating organ specific effects of these agents in different species.


Asunto(s)
Aflatoxina B1/toxicidad , Carcinógenos/toxicidad , Ensayo Cometa/métodos , Protectores contra Radiación/farmacología , Animales , Sangre/efectos de los fármacos , Bagres/genética , Daño del ADN/efectos de los fármacos , Riñón/efectos de los fármacos , Riñón/fisiología , Hígado/efectos de los fármacos , Hígado/fisiología , Oncorhynchus mykiss
15.
J Manipulative Physiol Ther ; 18(2): 72-8, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7790786

RESUMEN

OBJECTIVE: To determine the comparative rate of resolution of a contusion resulting from mechanical trauma to skeletal muscle, as a function of one of four exercise regimens. DESIGN: Randomized control trial. The four exercise regimens were: running with its onset immediately after injury, running with a 72 hr delay after injury, swimming with immediate onset, or swimming with a 72 hr delay. Control did not exercise. SETTING: Small-animal laboratory. PARTICIPANTS: Male Sprague-Dawley rats. INTERVENTION: A small animal traumatizing machine applied to the biceps femoris. MAIN OUTCOME MEASURES: The rate of contusion resolution was determined by a manual count of erythrocytes, leukocytes and collagen fibers in the contusion, and the data were analyzed using analysis of variance. RESULTS: Exercise of any type produced a greater decline in erythrocyte count (28.2% after 32 days vs. control) than no exercise. Immediate onset of any of the exercise regimens after injury resulted in a greater decline in erythrocyte count (32.7% after 32 days vs. control) and in leukocyte count (17.3% after 32 days vs. control) than delayed onset. Running with either immediate or delayed onset of exercise after injury produced a greater decline in erythrocyte count (36.2% after 32 days vs. control) than swimming. Running with its onset immediately after injury produced the greatest overall rate of decrease in erythrocyte count (44.8% after 32 days vs. control), and the second greatest overall rate of decrease in leukocyte count (15.0% after 32 days vs. control). CONCLUSIONS: Running with immediate onset is the regimen of choice. Any of the given exercises is preferable to no exercise, immediate onset of exercise is preferable to delayed onset, and running is preferable to swimming.


Asunto(s)
Colágeno/metabolismo , Contusiones/fisiopatología , Músculo Esquelético/fisiología , Esfuerzo Físico/fisiología , Análisis de Varianza , Animales , Contusiones/sangre , Contusiones/inmunología , Recuento de Eritrocitos , Recuento de Leucocitos , Masculino , Músculo Esquelético/inmunología , Músculo Esquelético/metabolismo , Ratas , Ratas Sprague-Dawley , Carrera , Natación
16.
J Parasitol ; 78(3): 541-3, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1597806

RESUMEN

Metacercariae of Diplostomum mordax were found in the cranial cavity of Orestias agasii, Orestias olivaceous, Orestias luteus, and Basilichthys bonariensis, fishes from Lake Titicaca, Peru. Metacercariae were not found in Oncorhynchus mykiss introduced into the lake during 1939 and 1940. Compression of neural tissue within and on the surface of the brain was observed in all infected fishes. Metacercariae migrating into the cerebrum and cerebellum of the piscine host caused hemorrhaging, cell necrosis, inflammation, fiber formation, and nerve fiber disruption. The presence of D. mordax in B. bonariensis and the 3 species of Orestias constitute new host records. Infections in the cerebrum and cerebellum add new information on specific parasite location.


Asunto(s)
Encéfalo/parasitología , Cerebelo/parasitología , Enfermedades de los Peces/parasitología , Trematodos/fisiología , Infecciones por Trematodos/veterinaria , Animales , Peces , Agua Dulce , Perú , Trematodos/aislamiento & purificación , Infecciones por Trematodos/parasitología
17.
J Parasitol ; 78(1): 34-9, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1738067

RESUMEN

Neoechinorhynchus idahoensis is described from Catostomus columbianus caught in the Salmon River, Stanley Basin, Idaho. The new species is closest to Neoechinorhynchus venustus Lynch, 1936, but is distinguished from it by its smaller and variably structured eggs, anterio-dorsal trunk hump, bent and posteriorly notched proboscis receptacle, and larger proboscis, proboscis receptacle, and hooks. It is distinguished also from 2 other species of Neoechinorhynchus with proboscis hooks in middle and anterior circles about equally large and from 7 other species having lemnisci greatly unequal in length. Histopathology of host tissue showed limited host response exemplified by epithelial damage and hemorrhaging at point of proboscis attachment with subsequent macrophage and other phagocytic cell migration. The proboscis extended through the host epithelium into the submucosa with limited hemorrhaging at the point of attachment. Unorganized collagenous fibers were present. The lumen of the host intestine was obstructed, and compressed villi were present. The trunk of the worm damaged intestinal epithelium near the crypts, causing localized inflammation. The caryophyllaeid cestode Isoglaridacris calentinei Mackiewicz, 1974, was present in concurrent infections of C. columbianus.


Asunto(s)
Acantocéfalos/anatomía & histología , Cipriniformes/parasitología , Enfermedades de los Peces/parasitología , Parasitosis Intestinales/veterinaria , Acantocéfalos/clasificación , Animales , Femenino , Enfermedades de los Peces/patología , Idaho , Parasitosis Intestinales/parasitología , Parasitosis Intestinales/patología , Mucosa Intestinal/parasitología , Mucosa Intestinal/patología , Intestinos/parasitología , Intestinos/patología , Masculino
18.
Am J Sports Med ; 19(5): 435-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1962706

RESUMEN

We investigated the effects of peritendon injections of hydrocortisone acetate on the separation force required to completely avulse a posttraumatized Achilles tendon of the adult male rat. One hundred thirty-five rats were randomly assigned to 3 groups and subsequently traumatized, treated, and sacrificed. One group was used to examine the effect of trauma; the second to examine effects of trauma and injections of hydrocortisone acetate on the tension to failure strength of tendons; the third group was the control group. Injected animals received one, three, or five injections of 0.10 cc (125 mg/ml) hydrocortisone acetate and were sacrificed 3, 6, or 9 weeks following initial injection. Experimental animals (anesthetized) were traumatized by dropping a weight onto the Achilles tendon. The tendon was tested in tension to failure employing a soft tissue linear disseminator. Histologic analysis using light microscopy was performed. We concluded that hydrocortisone acetate has no deleterious effect on the rat Achilles tendon as measured biomechanically or histologically.


Asunto(s)
Tendón Calcáneo , Hidrocortisona/análogos & derivados , Traumatismos de los Tendones/tratamiento farmacológico , Tendón Calcáneo/lesiones , Tendón Calcáneo/patología , Animales , Fenómenos Biomecánicos , Hidrocortisona/administración & dosificación , Hidrocortisona/farmacología , Inyecciones , Masculino , Ratas , Ratas Endogámicas , Traumatismos de los Tendones/patología
19.
J Parasitol ; 77(2): 201-5, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2010853

RESUMEN

Polymorphus spindlatus n. sp. is described from the black-crowned night heron, Nycticorax nycticorax, in Lake Titicaca, Peru. It is distinguished from all 27 known species of the subgenus Polymorphus by its spindle-shaped proboscis and its trunk shape, the anterior 2/3 of which is ovoid, tapering into a tubular posterior end. It resembles Polymorphus brevis (=Arhythmorhynchus brevis), which is, however, longer and considerably more slender, and has smaller and more numerous proboscis hooks per row and smaller eggs. It is separated also from Polymorphus swartzi, Polymorphus striatus, Polymorphus contortus, and Polymorphus cincli by its proboscis armature (usually 18 longitudinal rows of 11-13 hooks each), among other characters. Histopathological sections of host tissue show well defined localized damage including hemorrhaging with subsequent phagocyte cell migration (granular tissue). The lumen of the host intestine is obstructed and villi show compression. The proboscis of P. spindlatus extends through the intestinal mucosa and submucosa, displacing the smooth muscle layers of the muscularis externa. Fibrosis also was observed.


Asunto(s)
Acantocéfalos/clasificación , Enfermedades de las Aves/parasitología , Helmintiasis Animal , Parasitosis Intestinales/veterinaria , Acantocéfalos/anatomía & histología , Acantocéfalos/fisiología , Animales , Aves , Femenino , Helmintiasis/parasitología , Interacciones Huésped-Parásitos , Parasitosis Intestinales/parasitología , Intestinos/parasitología , Masculino
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