Microdissection testicular sperm extraction causes spermatogenic alterations in the contralateral testis

Testicular sperm extraction (TESE) associated with intracytoplasmic sperm injection has allowed many men presenting non-obstructive azoospermia to achieve fatherhood. Microdissection TESE (microTESE) was proposed as a method to improve sperm retrieval rates in these patients; however, there have been failures. Little is known about whether microTESE leads to spermatogenic alterations in the contralateral testis. We assessed histological outcomes of experimental microTESE in the contralateral testis of adult male rabbits. Nine adult male rabbits were divided into three groups: control (testicular biopsy to observe normal histological and morphometric values), sham (incision of the tunica vaginalis, and a contralateral testicular biopsy to observe histological and morphometric patterns, 45 days later), and study (left testicular microTESE, and a right testicular biopsy to observe histological and morphometric patterns, 45 days later). Sections were assessed by calculating Johnsen-like scores, and measuring total tubule diameter, lumen diameter and epithelial height. the results were compared using ANOVA and Bonferroni's statistical analysis. Morphometric evaluation of the seminiferous tubules did not demonstrate differences between the three groups. However, microTESE caused spermatogenic alterations, leading to maturation arrest in the contralateral testis.Universidade Federal de São Paulo, Dept Cirurgia, Div Urol, Secao Reprod Humana, São Paulo, BrazilUniv Estadual Paulista, Dept Biol, Inst Biociencias Letras & Ciencias Exatas Sao Jos, Sao Jose Do Rio Preto, SP, BrazilUniversidade Federal de São Paulo, Dept Cirurgia, Div Urol, Secao Reprod Humana, São Paulo, BrazilWeb of Scienc

Spermatogenesis and nucleolar activity in Triatoma klugi (Triatomine, Heteroptera)

Triatoma klugi is a Chagas disease vector in the Rio Grande do Sul State. Triatominae chromosomes are holocentric and sex chromosomes segregation is post-reductional. In this paper we describe the karyotype of male T. klugi and a meiotic analysis including the nucleolar behavior during spermatogenesis. Testis cells were analyzed after lacto-acetic orcein and silver nitrate staining. Two autosomes and the heterochromosomes presented nucleolar activity (Ag-NORs) during diplotene-diakinesis. The analysis of metaphase I and II revealed a karyotype with 2n = 20+XY. In metaphase I a prominent nucleolar mass was observed in the cell periphery and small silver grains were detected in metaphase II. During anaphase, the chromosomes segregated in parallel and a typical holocentric late migration behavior was observed. The restoration of the nucleolus was an important feature in this phase. During telophase nucleolar masses persisted and in early spermiogenesis the spermatids presented a small peripheral mass until elongation. The present study is a contribution to the study of chromatin behavior and nucleolar persistence in meiosis

Nucleolar Cycle and Its Correlation with Chromatoid Bodies in the Tilapia rendalli (Teleostei, Cichlidae) Spermatogenesis

The aim of this study was: (1) to monitor the nucleolar material distribution using cytological and cytochemical techniques and ultrastructural analysis; and (2) to compare the nucleolar material distribution with the formation of the chromatoid body (CB) in the germ epithelium of Tilapia rendalli. Nucleolar fragmentation occurred during the leptotene of prophase I and nucleolus reorganization occurred in the early spermatid nucleus. The area of the early spermatid nucleolus was significantly smaller than that of the spermatogonia nucleolus. Ultrastructural analysis showed an accumulation of nuages, which form the CB, before nucleolar fragmentation in the spermatogonia cytoplasm. The CB was observed in association with mitochondrial clusters in the cytoplasm of primary spermatocytes, as well as in those of initial and later spermatids. In conclusion, the nucleolus seems to be related to CB formation during spermatogenesis of T rendalli, because at the moment of nucleolus fragmentation in the primary spermatocytes, the CB reaches its largest area and it is able to complete important functions during spermatogenesis. The reorganized nucleolus of the initial spermatids has a lower area due several factors, one of which is the probable migration of nucleolar fragments from the nucleus to the cytoplasm, therefore playing a role in CB formation. Anat Rec, 293:900-910, 2010. (C) 2010 Wiley-Liss, Inc.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Mg 2+-dependent atpase activity In Malpighian tubules of Triatoma infestans Klug

Mg 2+-dependent ATPases were investigated in Malpighian tubules of the blood-sucking insect, Triatoma infestans, with cytochemical procedures for light and electron microscopy. The aim was to establish patterns of enzyme occurrence in the blood-sucking insect under control rearing conditions for further comparisons with animals subjected to the action of stress factors. Enzyme activity was found in laminated " concretions" present in distal cells, in edges of urate crystals at the lumen of the proximal region of tubules, in the basement membrane of proximal cells, and variously distributed in plasmalemma invaginations of both distal and proximal cells. Presence of ATPases in the " concretions" and urate crystals is presumed to be due to engulfment of other ATPase-containing components during formation of these structures. Cytochemical reactivity in the basement membrane and plasmalemma invaginations is assumed to be involved with active transport of waste molecules from and to hemolymph and differs as a function of the Malpighian tubule region. This paper provides a basic understanding of the enzyme occurrence in the blood sucking insects, and can be used as a pattern for comparative means of the staining patterns among Triatominae species. © 2011 Elsevier Ltd.Mg 2+-dependent ATPases were investigated in Malpighian tubules of the blood-sucking insect, Triatoma infestans, with cytochemical procedures for light and electron microscopy. The aim was to establish patterns of enzyme occurrence in the blood-sucking insect under control rearing conditions for further comparisons with animals subjected to the action of stress factors. Enzyme activity was found in laminated " concretions" present in distal cells, in edges of urate crystals at the lumen of the proximal region of tubules, in the basement membrane of proximal cells, and variously distributed in plasmalemma invaginations of both distal and proximal cells. Presence of ATPases in the " concretions" and urate crystals is presumed to be due to engulfment of other ATPase-containing components during formation of these structures. Cytochemical reactivity in the basement membrane and plasmalemma invaginations is assumed to be involved with active transport of waste molecules from and to hemolymph and differs as a function of the Malpighian tubule region. This paper provides a basic understanding of the enzyme occurrence in the blood sucking insects, and can be used as a pattern for comparative means of the staining patterns among Triatominae species.Mg 2+-dependent ATPases were investigated in Malpighian tubules of the blood-sucking insect, Triatoma infestans, with cytochemical procedures for light and electron microscopy. The aim was to establish patterns of enzyme occurrence in the blood-sucking insect under control rearing conditions for further comparisons with animals subjected to the action of stress factors. Enzyme activity was found in laminated " concretions" present in distal cells, in edges of urate crystals at the lumen of the proximal region of tubules, in the basement membrane of proximal cells, and variously distributed in plasmalemma invaginations of both distal and proximal cells. Presence of ATPases in the " concretions" and urate crystals is presumed to be due to engulfment of other ATPase-containing components during formation of these structures. Cytochemical reactivity in the basement membrane and plasmalemma invaginations is assumed to be involved with active transport of waste molecules from and to hemolymph and differs as a function of the Malpighian tubule region. This paper provides a basic understanding of the enzyme occurrence in the blood sucking insects, and can be used as a pattern for comparative means of the staining patterns among Triatominae species.43229830

Morphological changes of mammalian nucleoli during spermatogenesis and their possible role in the chromatoid body assembling

Chromatoid body (CB) is a typical cytoplasmic organelle of germ cells, and it seems to be involved in RNA/protein accumulation for later germ-cell differentiation. Despite most of the events in mammals spermatogenesis had been widely described in the past decades and the increase in the studies related to the CB molecular composition and physiology, the origins and functions of this important structure of male germ cells are still unclear. The aims of this study were to describe the nucleolar cycle and also to find some relationship between the nucleolar organization and the CB assembling during the spermatogenesis in mammals. Cytochemical and cytogenetics analysis showed nucleolar fragmentation in post-pachytene spermatocytes and nucleolar reorganization in post-meiotic spermatids. Significant difference in the number and in the size of nucleoli between spermatogonia and round spermatids, as well as differences in the nucleolar position within the nucleus were also observed. Ultrastructural analysis showed the CB assembling in the cytoplasm of primary spermatocytes and the nucleolar fragmentation occurring at the same time. In conclusion our results suggest that the CB may play important roles during the spermatogenesis process in mammals and that its origin may be related to the nucleolar cycle during the meiotic cell cycle

Ultrastructural analysis of the nucleolar aspects at spermiogenesis in triatomines (Heteroptera, Triatominae)

In this study the ultrastructural technique was used to analyze seminiferous tubule cells of the triatomine species Panstrongylus megistus, Rhodnius pallescens and Triatoma infestans. The data obtained provided evidence of the phenomenon known as persistence of the nucleolar material in initial spermatids at early differentiation. Our results confirmed the presence of the nucleolus and its products during spermiogenesis up to the formation of the axoneme and during spermatid elongation in all three species studied, similar to the process that takes place during cell division. In early spermatids, the nucleoli had a reticulate appearance and a well defined nucleolonema in P. megistus; showed a clear distinction between the fibrillar and the granular component in T. infestans; and had a compact aspect in R. pallescens. In this study, ultrastructural analyses at spermiogenesis indicated that these nucleolar products may represent RNP complexes that will probably be needed at early spermiogenesis when important changes such as chromatin condensation and acrosome and flagellum formation take place. Therefore, it was concluded from the ultrastructural analysis that the triatomine nucleolus does not totally disappear but remains as corpuscles that gather to form the next nucleolar cycle that in the case of meiosis, will be completed if fertilization occurs and a zygote is formed. (c) 2010 Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Mg2+-dependent ATPase activity in Malpighian tubules of Triatoma infestans Klug

Mg2+-dependent ATPases were investigated in Malpighian tubules of the blood-sucking insect, Triatoma infestans, with cytochemical procedures for light and electron microscopy. The aim was to establish patterns of enzyme occurrence in the blood-sucking insect under control rearing conditions for further comparisons with animals subjected to the action of stress factors. Enzyme activity was found in laminated "concretions" present in distal cells, in edges of urate crystals at the lumen of the proximal region of tubules, in the basement membrane of proximal cells, and variously distributed in plasmalemma invaginations of both distal and proximal cells. Presence of ATPases in the "concretions" and urate crystals is presumed to be due to engulfment of other ATPase-containing components during formation of these structures. Cytochemical reactivity in the basement membrane and plasmalemma invaginations is assumed to be involved with active transport of waste molecules from and to hemolymph and differs as a function of the Malpighian tubule region. This paper provides a basic understanding of the enzyme occurrence in the blood sucking insects, and can be used as a pattern for comparative means of the staining patterns among Triatominae species. (C) 2011 Elsevier Ltd. All rights reserved