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Volker Storch - One of the best experts on this subject based on the ideXlab platform.
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microscopic anatomy and ultrastructure of the Male Genital System in porocephalus crotali and p stilesi pentastomida porocephalida
Parasitology Research, 1990Co-Authors: Volker Storch, Wolfgang Böckeler, John RileyAbstract:The Male Genital SystemPorocephalus crotali andP. stilesi consists of an unpaired testis, Y-shaped or paired seminal vesicles, paired ejaculatory bulbs (ducts), vasa deferentia, cirri, cirrus sacs, and dilators. Cirri and dilators can travel into the Genital atrium. An ultrastructural analysis of each of these components is presented, including sperm development, which has been traced through some important stages. The main differences between the Male Genital Systems of the two subgroups of Pentastomida (Cephalobaenida and Porocephalida) concern the anatomy of the seminal vesicle, the shape and ultrastructure of the ejaculatory bulbs (ducts), the existence of cirrus sacs, the length of the coiled cirrus within the sacs, and the structure of the dilators. However, ultrastructural features reveal homologies between the various components of the Male Genital Systems of cephalobaenids and porocephalids.
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Microscopic anatomy and ultrastructure of the Male Genital System inPorocephalus crotali andP. stilesi (Pentastomida: Porocephalida)
Parasitology Research, 1990Co-Authors: Volker Storch, Wolfgang Böckeler, John RileyAbstract:The Male Genital System Porocephalus crotali and P. stilesi consists of an unpaired testis, Y-shaped or paired seminal vesicles, paired ejaculatory bulbs (ducts), vasa deferentia, cirri, cirrus sacs, and dilators. Cirri and dilators can travel into the Genital atrium. An ultrastructural analysis of each of these components is presented, including sperm development, which has been traced through some important stages. The main differences between the Male Genital Systems of the two subgroups of Pentastomida (Cephalobaenida and Porocephalida) concern the anatomy of the seminal vesicle, the shape and ultrastructure of the ejaculatory bulbs (ducts), the existence of cirrus sacs, the length of the coiled cirrus within the sacs, and the structure of the dilators. However, ultrastructural features reveal homologies between the various components of the Male Genital Systems of cephalobaenids and porocephalids.
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Ultrastructural analysis of the Male Genital System ofCephalobaena tetrapoda Heymons, 1922 (Pentastomida)
Parasitology Research, 1990Co-Authors: Wolfgang Böckeler, Volker StorchAbstract:The Male Genital System of Cephalobaena tetrapoda comprises the unpaired testis and seminal vesicle and the paired connecting tubes, ejaculatory bulbs, vasa deferentia, and dilators. These lead into the Genital atrium, which can be everted to form the copulatory organ. An ultrastructural analysis of each of these compounds is presented, including spermiogenesis, which was traced in some important stages. The diverging nomenclature of the complicated Male Genital System was unified and partly changed: where the vas deferens and dilator merge, the former loses its epithelial lining; the cuticular tube is called the cirrus. Anteriorly, the dilator also gives rise to a cuticular, semilunar tube. The cirrus and semilunar tube run parallel and reach the Genital atrium, which can be evaginated to form the copulatory organ. Apparently, the Male Genital System represents an original type from which the complicated porocephalic Systems may be derived.
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ultrastructural analysis of the Male Genital System of cephalobaena tetrapoda heymons 1922 pentastomida
Parasitology Research, 1990Co-Authors: W Bockeler, Volker StorchAbstract:The Male Genital System ofCephalobaena tetrapoda comprises the unpaired testis and seminal vesicle and the paired connecting tubes, ejaculatory bulbs, vasa deferentia, and dilators. These lead into the Genital atrium, which can be everted to form the copulatory organ. An ultrastructural analysis of each of these compounds is presented, including spermiogenesis, which was traced in some important stages. The diverging nomenclature of the complicated Male Genital System was unified and partly changed: where the vas deferens and dilator merge, the former loses its epithelial lining; the cuticular tube is called the cirrus. Anteriorly, the dilator also gives rise to a cuticular, semilunar tube. The cirrus and semilunar tube run parallel and reach the Genital atrium, which can be evaginated to form the copulatory organ. Apparently, the Male Genital System represents an original type from which the complicated porocephalic Systems may be derived.
Peter Michalik - One of the best experts on this subject based on the ideXlab platform.
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Spermatozoa and spermiogenesis of the wolf spider Schizocosa malitiosa (Lycosidae, Araneae) and its functional and phylogenetic implications
Zoomorphology, 2013Co-Authors: Peter Michalik, Anita Aisenberg, Rodrigo Postiglioni, Elisabeth LipkeAbstract:The wolf spider Schizocosa malitiosa is a well-known model System for studies on sexual selection in spiders. Despite this, little is known about the morphology of the reproductive System and spermatozoa in this species. In the present study, we investigate the Male Genital System and sperm cells of S. malitiosa using electron microscopy and provide a computer-based 3D reconstruction of the spermatozoa for the first time for arthropods. In general, the Male Genital System consists of two long, tube-like testes that lead into convoluted deferent ducts. The ejaculatory duct is enlarged and contains a large quantity of sperm and secretion. As revealed by transmission electron microscopy, only one type of secretion droplet is present in the seminal fluid. The spermatozoa of S. malitiosa resemble an organization known for members of the RTA clade, i.e., with an arrow-shaped acrosomal vacuole partly sunk into the nucleus and a chambered centriolar adjunct (a newly introduced character). This organization provides further support for these characters as potential synapomorphies for the RTA clade. By the end of the spermiogenesis, the nucleus and axoneme coils within the cell and a multi-layered secretion sheath are formed representing cleistospermia. The function of the thick secretion sheath is still unknown, but might be correlated either with the residency time in the feMale (insemination until oviposition) since feMale S. malitiosa do not lay eggs before the fourth month after copulation or with the receptivity-inhibiting substances suggested for this species.
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the Male Genital System of goblin spiders evidence for the monophyly of oonopidae arachnida araneae
American Museum Novitates, 2010Co-Authors: Matthias Burger, Peter MichalikAbstract:Abstract The Male reproductive System of spiders consists of paired, tubular testes and often long and convoluted deferent ducts, which are fused near the Genital opening to form an ejaculatory duct. In rare cases and as revealed in previous studies the testes can be partly fused (anteriorly or posteriorly), as reported, for example, for Dysderidae (Dysderoidea). In order to determine whether this pattern is also present in other dysderoids, we studied the Genital System of Oonopidae for the first time by means of light microscopy. The following species were included, covering both conventionally recognized subfamilies (Gamasomorphinae and Oonopinae): Neoxyphinus ogloblini Biraben, 1953; Silhouettella loricatula (Roewer, 1942); Opopaea recondita Chickering, 1951; Myrmopopaea sp.; Scaphiella hespera Chamberlin, 1924; Lionneta sp.; Orchestina moaba Chamberlin and Ivie, 1935; Oonops balanus Chickering, 1971, and Stenoonops reductus (Bryant, 1942). In contrast to other spider taxa observed to date, all studie...
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live for the moment adaptations in the Male Genital System of a sexually cannibalistic spider theridiidae araneae
Tissue & Cell, 2010Co-Authors: Peter Michalik, Barbara Knoflach, Konrad Thaler, Gerd AlbertiAbstract:Monogyny in spiders culminates in extreme traits, like dramatic Male self-sacrifice and emasculation of the Male by the feMale during copulation. Here we show that monogynous Males can be highly adapted for this fatal sexual behaviour. Dwarf Males of the one-palped theridiid spider Tidarren argo, which are cannibalised immediately after the insertion of their single copulatory organ, stop spermiogenesis when reaching adulthood. Their testes atrophy, which might economise the energy expenditures of these Males. We also found that the amount of seminal fluid produced is stored in an enlarged seminal vesicle until the single sperm induction takes place. The volume of the seminal vesicle is similar to the sperm droplet taken up into the copulatory organ (palpal organ). Sperm uptake takes much longer than in related species most likely due to the large amount of seminal fluid. As shown by histological observations Males are able to fill one of the paired feMale sperm storage organs during copulation thereby presumably impeding subsequent charging by rival Males.
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Live for the moment—Adaptations in the Male Genital System of a sexually cannibalistic spider (Theridiidae, Araneae)
Tissue & Cell, 2009Co-Authors: Peter Michalik, Barbara Knoflach, Konrad Thaler, Gerd AlbertiAbstract:Monogyny in spiders culminates in extreme traits, like dramatic Male self-sacrifice and emasculation of the Male by the feMale during copulation. Here we show that monogynous Males can be highly adapted for this fatal sexual behaviour. Dwarf Males of the one-palped theridiid spider Tidarren argo, which are cannibalised immediately after the insertion of their single copulatory organ, stop spermiogenesis when reaching adulthood. Their testes atrophy, which might economise the energy expenditures of these Males. We also found that the amount of seminal fluid produced is stored in an enlarged seminal vesicle until the single sperm induction takes place. The volume of the seminal vesicle is similar to the sperm droplet taken up into the copulatory organ (palpal organ). Sperm uptake takes much longer than in related species most likely due to the large amount of seminal fluid. As shown by histological observations Males are able to fill one of the paired feMale sperm storage organs during copulation thereby presumably impeding subsequent charging by rival Males.
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the Male Genital System of the new world ricinulei arachnida ultrastructure of spermatozoa and spermiogenesis with special emphasis on its phylogenetic implications
Arthropod Structure & Development, 2008Co-Authors: Giovanni Talarico, L Garcia F Hernandez, Peter MichalikAbstract:This study is the first report on the Male Genital System and the sperm structure of the South American genus Cryptocellus and provides a second description for the Central American genus Pseudocellus. The spermatids of the Colombian species Cryptocellus narino are elongated and anteriorly lentoid-shaped due to two conspicuous intracellular electron-dense plates. Two cell protrusions are present, which contain in front of the lentoid part the acrosomal complex and parts of the axoneme and nucleus, and behind the lentoid part the continuing axoneme and nucleus. The acrosomal filament originates from a cap-like acrosomal vacuole, extends into the nuclear canal and ends behind the lentoid part. The nucleus runs parallel to the axoneme. The axoneme possesses a typical 9 + 2 microtubular pattern. At the end of spermiogenesis the acrosomal complex, nucleus and axoneme coil within the cell forming cleistospermia as transfer form. Our results of Pseudocellus pearsei confirm an earlier study on that genus which is considered to be not closely related to Cryptocellus. According to the present study the sperm structure of the observed Cryptocellus species is very similar to what is described for Pseudocellus.
John Riley - One of the best experts on this subject based on the ideXlab platform.
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microscopic anatomy and ultrastructure of the Male Genital System in porocephalus crotali and p stilesi pentastomida porocephalida
Parasitology Research, 1990Co-Authors: Volker Storch, Wolfgang Böckeler, John RileyAbstract:The Male Genital SystemPorocephalus crotali andP. stilesi consists of an unpaired testis, Y-shaped or paired seminal vesicles, paired ejaculatory bulbs (ducts), vasa deferentia, cirri, cirrus sacs, and dilators. Cirri and dilators can travel into the Genital atrium. An ultrastructural analysis of each of these components is presented, including sperm development, which has been traced through some important stages. The main differences between the Male Genital Systems of the two subgroups of Pentastomida (Cephalobaenida and Porocephalida) concern the anatomy of the seminal vesicle, the shape and ultrastructure of the ejaculatory bulbs (ducts), the existence of cirrus sacs, the length of the coiled cirrus within the sacs, and the structure of the dilators. However, ultrastructural features reveal homologies between the various components of the Male Genital Systems of cephalobaenids and porocephalids.
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Microscopic anatomy and ultrastructure of the Male Genital System inPorocephalus crotali andP. stilesi (Pentastomida: Porocephalida)
Parasitology Research, 1990Co-Authors: Volker Storch, Wolfgang Böckeler, John RileyAbstract:The Male Genital System Porocephalus crotali and P. stilesi consists of an unpaired testis, Y-shaped or paired seminal vesicles, paired ejaculatory bulbs (ducts), vasa deferentia, cirri, cirrus sacs, and dilators. Cirri and dilators can travel into the Genital atrium. An ultrastructural analysis of each of these components is presented, including sperm development, which has been traced through some important stages. The main differences between the Male Genital Systems of the two subgroups of Pentastomida (Cephalobaenida and Porocephalida) concern the anatomy of the seminal vesicle, the shape and ultrastructure of the ejaculatory bulbs (ducts), the existence of cirrus sacs, the length of the coiled cirrus within the sacs, and the structure of the dilators. However, ultrastructural features reveal homologies between the various components of the Male Genital Systems of cephalobaenids and porocephalids.
Wolfgang Böckeler - One of the best experts on this subject based on the ideXlab platform.
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microscopic anatomy and ultrastructure of the Male Genital System in porocephalus crotali and p stilesi pentastomida porocephalida
Parasitology Research, 1990Co-Authors: Volker Storch, Wolfgang Böckeler, John RileyAbstract:The Male Genital SystemPorocephalus crotali andP. stilesi consists of an unpaired testis, Y-shaped or paired seminal vesicles, paired ejaculatory bulbs (ducts), vasa deferentia, cirri, cirrus sacs, and dilators. Cirri and dilators can travel into the Genital atrium. An ultrastructural analysis of each of these components is presented, including sperm development, which has been traced through some important stages. The main differences between the Male Genital Systems of the two subgroups of Pentastomida (Cephalobaenida and Porocephalida) concern the anatomy of the seminal vesicle, the shape and ultrastructure of the ejaculatory bulbs (ducts), the existence of cirrus sacs, the length of the coiled cirrus within the sacs, and the structure of the dilators. However, ultrastructural features reveal homologies between the various components of the Male Genital Systems of cephalobaenids and porocephalids.
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Microscopic anatomy and ultrastructure of the Male Genital System inPorocephalus crotali andP. stilesi (Pentastomida: Porocephalida)
Parasitology Research, 1990Co-Authors: Volker Storch, Wolfgang Böckeler, John RileyAbstract:The Male Genital System Porocephalus crotali and P. stilesi consists of an unpaired testis, Y-shaped or paired seminal vesicles, paired ejaculatory bulbs (ducts), vasa deferentia, cirri, cirrus sacs, and dilators. Cirri and dilators can travel into the Genital atrium. An ultrastructural analysis of each of these components is presented, including sperm development, which has been traced through some important stages. The main differences between the Male Genital Systems of the two subgroups of Pentastomida (Cephalobaenida and Porocephalida) concern the anatomy of the seminal vesicle, the shape and ultrastructure of the ejaculatory bulbs (ducts), the existence of cirrus sacs, the length of the coiled cirrus within the sacs, and the structure of the dilators. However, ultrastructural features reveal homologies between the various components of the Male Genital Systems of cephalobaenids and porocephalids.
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Ultrastructural analysis of the Male Genital System ofCephalobaena tetrapoda Heymons, 1922 (Pentastomida)
Parasitology Research, 1990Co-Authors: Wolfgang Böckeler, Volker StorchAbstract:The Male Genital System of Cephalobaena tetrapoda comprises the unpaired testis and seminal vesicle and the paired connecting tubes, ejaculatory bulbs, vasa deferentia, and dilators. These lead into the Genital atrium, which can be everted to form the copulatory organ. An ultrastructural analysis of each of these compounds is presented, including spermiogenesis, which was traced in some important stages. The diverging nomenclature of the complicated Male Genital System was unified and partly changed: where the vas deferens and dilator merge, the former loses its epithelial lining; the cuticular tube is called the cirrus. Anteriorly, the dilator also gives rise to a cuticular, semilunar tube. The cirrus and semilunar tube run parallel and reach the Genital atrium, which can be evaginated to form the copulatory organ. Apparently, the Male Genital System represents an original type from which the complicated porocephalic Systems may be derived.
Phyllis A Wingo - One of the best experts on this subject based on the ideXlab platform.
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distribution of Male Genital System cancers mgsc united states 1999 2001
Annals of Epidemiology, 2005Co-Authors: Robert R German, Trevor D Thompson, Sherri L Stewart, Phyllis A WingoAbstract:Purpose MGSC comprise nearly a third of all cancers in Males. Prostate cancer (PrC) is the most commonly diagnosed cancer among Males, and the second leading cause of cancer-related deaths. Testicular cancer (TsC) is the most common solid tumor among Males aged 15–34 years. Penile (PnC) and other MGSC are uncommon. Recent national population-based data can further characterize these cancers. Methods Incidence data from 38 CDC-NPCR registries and 5 Surveillance, Epidemiology, and End Results (SEER) registries (i.e., 91% of the US), and mortality data from CDC's National Center for Health Statistics (100% of the United States), were used to calculate age-specific and age-adjusted rates in 1999–2001 for the United States. Results About 96% and 98% of MGSC cases and deaths, respectively, were PrC. Incidence and death rates of PnC increased with increasing age, as well as incidence rates of other MGSC. PrC rates increased up to 70–79 years, where incidence declined but mortality continued to increase. TsC rates peaked at about 30-39 years, where incidence declined while mortality declined then increased at 80+ years. Compared to white Males, age-adjusted incidence and death rates among black Males were about twice as high for PrC and five to two times lower for TsC. Rates of PnC and other MGSC did not vary appreciably by white/black race. Analysis of age-adjusted PrC rates by census region showed the Northeast (NE) having the highest incidence rate and the Midwest (MW) and South (S) with the highest death rates. PnC incidence rates were highest in the NE and MW, while PnC death rates were highest in the MW and S. The West had the highest death rates for TsC and the highest incidence rates for other MGSC. TsC incidence rates and other MGSC death rates did not vary appreciably by Census region. Conclusions Demographic variations in the occurrence of uncommon MGSC were observed. Additional analyses by stage, histology, and grade are planned.
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Distribution of Male Genital System Cancers (MGSC), United States – 1999–2001
Annals of Epidemiology, 2005Co-Authors: Robert R German, Trevor D Thompson, Sherri L Stewart, Phyllis A WingoAbstract:Purpose MGSC comprise nearly a third of all cancers in Males. Prostate cancer (PrC) is the most commonly diagnosed cancer among Males, and the second leading cause of cancer-related deaths. Testicular cancer (TsC) is the most common solid tumor among Males aged 15–34 years. Penile (PnC) and other MGSC are uncommon. Recent national population-based data can further characterize these cancers. Methods Incidence data from 38 CDC-NPCR registries and 5 Surveillance, Epidemiology, and End Results (SEER) registries (i.e., 91% of the US), and mortality data from CDC's National Center for Health Statistics (100% of the United States), were used to calculate age-specific and age-adjusted rates in 1999–2001 for the United States. Results About 96% and 98% of MGSC cases and deaths, respectively, were PrC. Incidence and death rates of PnC increased with increasing age, as well as incidence rates of other MGSC. PrC rates increased up to 70–79 years, where incidence declined but mortality continued to increase. TsC rates peaked at about 30-39 years, where incidence declined while mortality declined then increased at 80+ years. Compared to white Males, age-adjusted incidence and death rates among black Males were about twice as high for PrC and five to two times lower for TsC. Rates of PnC and other MGSC did not vary appreciably by white/black race. Analysis of age-adjusted PrC rates by census region showed the Northeast (NE) having the highest incidence rate and the Midwest (MW) and South (S) with the highest death rates. PnC incidence rates were highest in the NE and MW, while PnC death rates were highest in the MW and S. The West had the highest death rates for TsC and the highest incidence rates for other MGSC. TsC incidence rates and other MGSC death rates did not vary appreciably by Census region. Conclusions Demographic variations in the occurrence of uncommon MGSC were observed. Additional analyses by stage, histology, and grade are planned.