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| 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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| 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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| 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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| 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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| RAMALHO-SANTOS,JOÃO; MORENO,RICARDO D.. |
| Regulated exocytosis is controlled by internal and external signals. The molecular machinery controlling the sorting from the newly synthesized vesicles from the Golgi apparatus to the plasma membrane play a key role in the regulation of both the number and spatial location of the vesicles. In this context the mammalian acrosome is a unique vesicle since it is the only secretory vesicle attached to the nucleus. In this work we have studied the membrane trafficking between the Golgi apparatus and the acrosome during mammalian spermiogenesis. During bovine spermiogenesis, Golgi antigens (mannosidase II) were detected in the acrosome until the late cap-phase spermatids, but are not found in testicular spermatozoa (maturation-phase spermatids). This suggests... |
| Tipo: Journal article |
Palavras-chave: Acrosome; Spermatid; Golgi; Fertilization; Spermiogenesis. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602001000200021 |
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