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Registros recuperados: 14
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A new vision of the origin and the oocyte development in the Ostariophysi applied to Gymnotus sylvius (Teleostei: Gymnotiformes) Neotropical Ichthyology
França,Gisleine Fernanda; Grier,Harry J.; Quagio-Grassiotto,Irani.
Based on new knowledge coming from marine perciform species, the origin of oocytes and their development in the Ostariophysi, Gymnotus sylvius is described. In both Gymnotus sylvius and marine perciform fish, oogonia are found in the germinal epithelium that forms the surface of the ovarian lamellae. At the commencement of folliculogenesis, proliferation of oogonia and their entrance into meiosis gives rise to germ cell nests that extend into the stroma from the germinal epithelium. Both cell nests and the germinal epithelium are supported by the same basement membrane that separates them from the stroma. At the time of meiotic arrest, oocytes in a cell nest become separated one from the other as processes of prefollicle cells, these being derived from...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Folliculogenesis; Primary growth; Secondary growth; Maturation; Ovulation.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252010000400008
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Comparative analysis of spermiogenesis and sperm ultrastructure in Callichthyidae (Teleostei: Ostariophysi: Siluriformes) Neotropical Ichthyology
Spadella,Maria A.; Oliveira,Claudio; Quagio-Grassiotto,Irani.
In Corydoradinae, the presence of spermatids in the lumen of the testicular tubules together with spermatozoa suggests that spermatogenesis is of the semicystic type, whereas in Callichthyinae, sperm production occurs entirely within spermatocysts in the germinal epithelium, characterizing cystic spermatogenesis. Spermiogenesis in Callichthyinae is characterized by an initial lateral development of the flagellum, the presence of nuclear rotation to different degrees, an eccentric or medial formation of a nuclear fossa, formation of a cytoplasmic channel, and presence of centriolar migration, being more similar to type I spermiogenesis. In Corydoradinae, spermiogenesis is characterized by eccentric development of the flagellum, the absence of nuclear...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Catfish; Spermatid; Spermatozoa; Phylogeny; Morphology.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300014
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Comparative description and discussion of spermiogenesis and spermatozoal ultrastructure in some species of Heptapteridae and Pseudopimelodidae (Teleostei: Siluriformes) Neotropical Ichthyology
Quagio-Grassiotto,Irani; Spadella,Maria Angélica; Carvalho,Márcio de; Oliveira,Claudio.
The data obtained in the present study on spermiogenesis and spermatozoal ultrastructure of Pseudopimelodidae and Heptapteridae show that they share some characteristics, but greatly differ from each other. The main differences are the occurrence of type I spermiogenesis in Pseudopimelodidae and type III in Heptapteridae, the presence of nuclear fossa in Pseudopimelodidae and its absence in Heptapteridae, the presence of long midpiece in Pseudopimelodidae and short midpiece in Heptapteridae, the presence of cytoplasmic canal in Pseudopimelodidae and its absence in Heptapteridae, the presence of many large vesicles in the midpiece of Pseudopimelodidae and the presence of very long vesicles placed in the peripheral distal region in Heptapteridae, and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Catfish; Spermatid; Sperm; Structure; Phylogeny.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252005000300008
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Dynamics and cytochemistry of oogenesis in Astyanax fasciatus (Cuvier) (Teleostei, Characiformes, Characidae) from Rio Sapucaí, Minas Gerais State, Brazil Zoologia
Garcia,José Antônio Dias; Chini,Helena A.S.; Maistro,Edson Luis; Quagio-Grassiotto,Irani.
Oogenesis involves a set of transformations which are undergone by female germ cells These cells change into oogonias and then into mature oocytes. Sexually mature female fish were collected monthly, during one year, from the Sapucaí River, a tributary of the Rio Grande, which is part of the Furnas Reservoir in the state of Minas Gerais. During the several stages of maturation, we observed small round oogonias with a large nucleus, a single nucleolus, and weakly stained cytoplasm with eosinophilic granules. The primary oocytes showed a large basophilic nucleus, with a developed peripheral nucleolus and a reduced cytoplasm. The previtellogenic oocytes presented voluminous cytoplasm and nucleus with several small peripheral nucleoli. The oocytes underwent...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Teleostei; Characidae; Astyanax fasciatus; Oogenesis; Cytochemical.
Ano: 2001 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752001000400003
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Dynamics and cytochemistry of oogenesis in Leporinus striatus Kner (Teleostei, Characiformes, Anostomidae) from the Rio Sapucaí, Minas Gerais State, Brazil Zoologia
Chini,Helena A.S.; Garcia,José Antônio Dias; Maistro,Edson Luis; Quagio-Grassiotto,Irani.
Oogenesis involves a sequense of transformations which are undergone by female germ cells. These cells change into oogonias and then into mature oocytes. Sexually mature females were collected monthly, during one year, from the Rio Sapucaí, tributary of the Rio Grande, which is part of the Furnas Reservoir system in the state of Minas Gerais. The observed material showed that oogonias were small spherical cells, had a big spherical nucleus, with a single nucleolus, and weakly stained cytoplasm with eosinophilic granules (FG stained), which indicate their protein content. The primary oocytes showed a big basophilic nucleus, with a large peripheral nucleolus, and several smaller nucleoli. They show a reduced cytoplasmic content. The previtellogenic oocytes...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Teleostei; Anostomidae; Leporinus striatus; Oogenesis; Cytochemical.
Ano: 2001 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752001000400004
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Markiana nigripinnis (Perugia, 1891) as a putative member of the subfamily Stevardiinae (Characiformes: Characidae): spermatic evidence Neotropical Ichthyology
Baicere-Silva,Clarianna Martins; Benine,Ricardo C.; Quagio-Grassiotto,Irani.
The genus Markiana was until recently recognized as incertae sedis in the family Characidae, even though alternative placements for this genus have been advanced since its original description. More recently, it was hypothesized that Markiana nigripinnis is part of a clade informally named the Astyanax clade, indicating the putative close relationship of Markiana with the genus Astyanax. Examination of sperm ultrastructure of representatives of Astyanax and M. nigripinnis shows no evidence for this hypothesized close relationship. Rather, the spermatozoa of M. nigripinnis share characters found in spermatozoa of the non-inseminating members of the subfamily Stevardiinae, such as an angle of nuclear rotation equal to 85º resulting in a lateral position of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Astyanax clade; Clade A; Spermiogenesis; Spermatozoa ultrastructure.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000200015
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Morphological regional differences of epithelial cells along the midgut in Diatraea saccharalis Fabricius (Lepidoptera: Crambidae) larvae Neotropical Entomology
Pinheiro,Daniela O.; Quagio-Grassiotto,Irani; Gregório,Elisa A..
The sugarcane borer, Diatraea saccharalis Fabricius, is a pest to sugarcane and many other crops. This work aims to characterize morphological variability in the epithelial cells (columnar, goblet and regenerative) along the midgut of D. saccharalis larvae. Fragments of the midgut (anterior, middle and posterior regions) were fixed and processed by light and scanning electron microscopy. There are both cytochemical and ultrastructural differences in the morphology of the epithelial cells, depending on their localization along the midgut. The apical surface of columnar cells shows an increase in both number and size of the apical protrusions from the anterior to the posterior midgut regions. There is an increase in the amount of PAS-positive (Periodic...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Morphology; Sugarcane borer; Histochemistry; Scanning electron microscopy; Light microscopy.
Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2008000400009
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Morphometric study of the midgut epithelium in larvae of Diatraea saccharalis Fabricius (Lepidoptera: Pyralidae) Neotropical Entomology
Pinheiro,Daniela O.; Silva,Reinaldo J.; Quagio-Grassiotto,Irani; Gregório,Elisa A..
The sugarcane borer, Diatraea saccharalis Fabricius, has great economical interest as it affects the culture and industrial use of the sugarcane. However, there are few studies concerning the internal morphology of this insect. This work aims to study morphometrically the midgut and the epithelium along their lenght, trying to characterize different regions. Midgut of last instar larvae was divided in three regions: anterior, middle and posterior, and the fragments were processed for light microscopic observation. Histological sections were analyzed in a computerized system concerning the length, width and area of the epithelium, their cells, and the midgut lumen. The obtained data were statistically analyzed by the Kruskal-Wallis test and by multivariate...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Morphometry; Epithelial cell; Insect; Sugarcane borer; Mesenteron.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2003000300012
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Sperm characteristics as additional evidence of close relationship between Lebiasina and Piabucina (Characiformes: Lebiasinidae: Lebiasininae) Neotropical Ichthyology
Santana,Júlio César de O.; Netto-Ferreira,André L.; Calcagnotto,Daniela; Quagio-Grassiotto,Irani.
Spermiogenesis and spermatozoa of representatives of the genera Lebiasina and Piabucinaare described. Spermiogenesis is quite similar among all analyzed species of these genera and is identified as Type II. In this type of spermiogenesis, the flagellum of earliest spermatids lies lateral to the nucleus. A slight movement of the nucleus towards the centriolar complex is observed. In late spermatids, the nucleus slightly elongates towards the flagellum. The formation of two striated rootlets apparently occurs in early/intermediate spermatids. The spermatozoa of species of Lebiasinaand Piabucina share (1) a drop-shaped slightly elongated nucleus that is laterally positioned relative to the flagellum; (2) a superolateral centriolar complex; (3) two striated...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Ostariophysi; Neotropical Fish; Spermatozoa; Systematics; Ultrastructure.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000300573
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Sperm evolution in the family Alestidae with comparative data for the genus Chalceus (Ostariophysi: Characiformes) Neotropical Ichthyology
Santana,Júlio César de O.; Calcagnotto,Daniela; Quagio-Grassiotto,Irani.
Spermiogenesis and spermatozoa in six genera of the African family Alestidae plus the Neotropical genus Chalceusare described. Spermiogenesis is quite similar in all Alestidae and is identified as Type I and its variants. In Type I spermiogenesis, the flagellum of earliest spermatids lies lateral to the nucleus, and rotation of the nucleus towards the centriolar complex is observed. Nuclear rotation is complete reaching 90 degrees in Bryconalestes longipinnis, Brachypetersius altus, Brycinus imberi, B. lateralis, and Alestopetersius compressus; and is incomplete reaching 20 degrees in Micralestes acutidensand Rhabdalestesrhodesiensis. Spermatozoa morphology varies from a medial nucleus with fibrillar chromatin in the most basal genus Brycinusto a strongly...
Tipo: Info:eu-repo/semantics/article Palavras-chave: African Fish; Ostariophysi; Spermatozoa; Systematics; Ultrastructure.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000200419
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Spermatic characteristics and sperm evolution on the subfamily Stevardiinae (Ostariophysi: Characiformes: Characidae) Neotropical Ichthyology
Baicere-Silva,Clarianna Martins; Ferreira,Katiane M.; Malabarba,Luiz R.; Benine,Ricardo C.; Quagio-Grassiotto,Irani.
The monophyly and phylogenetic relationships among the members of Clade A characids (sensu Malabarba & Weitzman), later redefined and named as the Stevardiinae (sensu Mirande), have been primarily supported by traditional morphological and molecular data. Herein were examined, described and compared spermiogenesis and sperm ultrastructure of 12 species of the genera Boehlkea, Bryconacidnus, Bryconamericus, Creagrutus, Cyanocharax, Hemibrycon, Knodus, Odontostoechus, Piabina, and Rhinobrycon in order to evaluate possible phylogenetic signals and their potential use in recovering relationships of the Stevardiinae. All examined species demonstrated a nuclear rotation equal or less than 95º resulting in a lateral position of the double nuclear fossa...
Tipo: Info:eu-repo/semantics/other Palavras-chave: Clade A; Phylogeny; Spermiogenesis; Sperm morphotype.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000200016
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Spermiogenesis and spermatozoa ultrastructure in five species of the Curimatidae with some considerations on spermatozoal ultrastructure in the Characiformes Neotropical Ichthyology
Quagio-Grassiotto,Irani; Gameiro,Maria Carolina; Schneider,Tatiana; Malabarba,Luiz Roberto; Oliveira,Claudio.
Spermiogenesis in the curimatid species, Steindachnerina insculpta, Cyphocharax gillii, C. modestus, C. spilotus, and Potamorhina altamazonica, is characterized by lateral development of the flagellum, nuclear rotation, eccentric nuclear fossa formation, and chromatin compacted into thick fibers. These spermatozoa exhibit a spherical head containing a nucleus with the chromatin highly condensed into thick fibers with small electron-lucent areas, and no acrosome. The nuclear fossa is of the moderate type and eccentric and penetrated by the centriolar complex. The midpiece is small, has many elongate vesicles, and a short cytoplasmic channel. Mitochondria may be elongate, branched or C-shaped, and are separated from the initial segment of the axoneme by the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Fish; Spermatid; Sperm; Ultrastructure.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252003000100004
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Spermiogenesis and spermatozoa ultrastructure in the Serrasalminae (Ostariophysi: Characiformes) with further evidence on the relationships of the piranhas and pacus Neotropical Ichthyology
Gusmão-Pompiani,Priscila; Malabarba,Luiz R.; Oliveira,Claudio; Quagio-Grassiotto,Irani.
Spermatozoa and spermiogenesis ultrastructure were studied in the serrasalmine species Piaractus mesopotamicus, Mylossoma duriventre, Serrasalmus maculatus, and Metynnis mola and two distinct patterns may be recognized: the first common to Mylossoma, Serrasalmus and Metynnis, and the other, characteristic of Piaractus. The latter pattern is more similar to the conditions found in Salminus and Brycon. On the other hand, serrasalmine spermatozoa also share characteristics with the spermatozoa of species of the superfamily Anostomoidea. The phylogenetic significance of these characters is discussed.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Characid; Spermatid; Spermatozoa; Phylogeny; Morphology.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000300005
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Two new species and a review of the inseminating freshwater fish genus Monotocheirodon (Characiformes: Characidae) from Peru and Bolivia Pap. Avulsos de Zool. (São Paulo)
Menezes,Naércio A.; Weitzman,Stanley H.; Quagio-Grassiotto,Irani.
Two new species of inseminating freshwater fishes of the genus Monotocheirodon, family Characidae, are described from Peru. Males and females of both new species have an external, visually obvious urogenital papilla that was not detected in the females in previous studies, with this longer in males, which use it as an inseminating organ. A third inseminating species from Bolivia, Monotocheirodon pearsoni, unstudied in any detail since its original description in 1924, is redescribed. This latter species lacks an inseminating organ. Monotocheirodon is redescribed, its phylogenetic relationships are briefly discussed and it is suggested that it is possibly related to the stevardiin genera Ceratobranchia, Othonocheirodus, and Odontostoechus.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Inseminating characid fishes; New species and relationships of Monotocheirodon.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492013001000001
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