scholarly journals Characterization of Extracellular Vesicles from Cilia and Epithelial Cells of Ductuli Efferentes in a Turtle (Pelodiscus sinensis)

Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 888 ◽  
Author(s):  
Imran Tarique ◽  
Yifei Liu ◽  
Xuebing Bai ◽  
Abdul Haseeb ◽  
Ping Yang ◽  
...  
Keyword(s):  
Extracellular Vesicles ◽  
Rete Testis ◽  
Freshwater Turtle ◽  
Secretory Proteins ◽  
Ciliated Cells ◽  
Pelodiscus Sinensis ◽  
Cytological Evidence ◽  
Turtle Species ◽  
Ductuli Efferentes ◽  
Perinuclear Cytoplasm

The ductuli efferentes (DE) form a transit passage for the passage of spermatozoa from the rete testis to the epididymis. After spermiation, various epithelial secretory proteins are transferred via extracellular vesicles (EVs) to the spermatozoa for their maturation and long-term viability. The aim of the present study was to investigate the distribution, classification, and source of multivesicular bodies (MVBs) and their EVs in the epithelia of the efferentes duct in a turtle species, the soft-shelled freshwater turtle Pelodiscus sinensis by using light and transmission electron microscopy. The results showed that CD63 as a classical exosome marker was strongly immunolocalized within the apical and lateral cytoplasm of the ciliated cells (CC) and moderate to weak in the non-ciliated cells (NCC) of DE. The ultrastructure revealed that early endosome was present at the basement membrane and perinuclear cytoplasm of both CC and NCC, whereas MVBs were located over the nucleus in the cytoplasm of NCC and adjacent to the basal bodies of cilia within the CC. Many EVs, as sources of MVBs, were located within the blebs that were attached to the cilia of CC, within the apical blebs from NCC, and the lateral spaces of CC and NCC. There was ultrastructure evidence of EVs associated with spermatozoa in the lumens of DE. Collectively, the present study provides cytological evidence that the DE epithelium secreted EVs to the lumen by (1) apical blebs, (2) ciliary blebs, and (3) from the basolateral region. These EVs were associated with spermatozoa in the DE lumen of this turtle. Characterization and cellular distribution of these EVs in the DE of a turtle may provide a study model to further investigate the transferring of micromolecules via EVs to the spermatozoa.

scholarly journals An Electron Microscopic Study of the Ductuli Efferentes and Rete Testis of the Guinea Pig

1958 ◽  
Vol 4 (2) ◽  
pp. 219-226 ◽  
Author(s):  
Aaron J. Ladman ◽  
William C. Young
Keyword(s):  
Endoplasmic Reticulum ◽  
Guinea Pig ◽  
Rete Testis ◽  
Ciliated Cells ◽  
Electron Microscopic ◽  
Cytoplasmic Vacuoles ◽  
Ductuli Efferentes ◽  
Size Number ◽  
Fluid Transfer ◽  
Electron Microscopes

The ductuli efferentes and rete testis of the guinea pig were isolated by micro dissection, fixed in cold buffered osmium tetroxide, and sectioned for examination with the light and electron microscopes. Proximal and distal segments of the ductuli efferentes were identified and their respective cytological organizations characterized. The cytological components of the rete testis are briefly described and figured. Non-ciliated and ciliated cells are found in both segments of the ductuli efferentes. The non-ciliated cells have a microvillous border, mitochondria, a Golgi complex, an ubiquitous endoplasmic reticulum, and numerous cytoplasmic vacuoles. The ciliated cells contain more mitochondria, an endoplasmic reticulum with a relatively sparse distribution, and few, if any, cytoplasmic vacuoles. A regional difference exists in proximal and distal segments based on the distribution, size, number, and electron opacity of the cytoplasmic vacuoles. Attention was paid to the disposition of the endoplasmic reticulum and its relation to the system of cytoplasmic vacuoles. These findings are interpreted as suggesting that the continuity of the vacuolar system with elements of the endoplasmic reticulum represents a pathway for transfer of large quantities of fluid, an activity which has long been ascribed to the epithelium of the ductuli efferentes. Periductular capillaries possess pore-like apertures in their endothelia similar to those in other tissues known to engage in fluid transfer.

scholarly journals Plastic ingestion by freshwater turtles: a review and call to action

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Adam G. Clause ◽  
Aaron J. Celestian ◽  
Gregory B. Pauly
Keyword(s):  
Marine Species ◽  
Marine Turtle ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Plastic Pollution ◽  
Potential Threat ◽  
Implementation Quality ◽  
Turtle Species ◽  
Marine Turtles ◽  
Conservation Concern

AbstractPlastic pollution, and especially plastic ingestion by animals, is a serious global issue. This problem is well documented in marine systems, but it is relatively understudied in freshwater systems. For turtles, it is unknown how plastic ingestion compares between marine and non-marine species. We review the relevant turtle dietary literature, and find that plastic ingestion is reported for all 7 marine turtle species, but only 5 of 352 non-marine turtle species. In the last 10 years, despite marine turtles representing just 2% of all turtle species, almost 50% of relevant turtle dietary studies involved only marine turtles. These results suggest that the potential threat of plastic ingestion is poorly studied in non-marine turtles. We also examine plastic ingestion frequency in a freshwater turtle population, finding that 7.7% of 65 turtles had ingested plastic. However, plastic-resembling organic material would have inflated our frequency results up to 40% higher were it not for verification using Raman spectroscopy. Additionally, we showcase how non-native turtles can be used as a proxy for understanding the potential for plastic ingestion by co-occurring native turtles of conservation concern. We conclude with recommendations for how scientists studying non-marine turtles can improve the implementation, quality, and discoverability of plastic ingestion research.

scholarly journals Mesenchymal stem cells versus their extracellular vesicles in treatment of liver fibrosis: Is it possible to compare?

2021 ◽  
Vol 9 (2) ◽  
Author(s):  
Noha Attia ◽  
Yasmine Khalifa ◽  
Dina Rostom ◽  
Mohamed Mashal
Keyword(s):  
Liver Fibrosis ◽  
Extracellular Vesicles ◽  
Therapeutic Strategy ◽  
Secretory Proteins ◽  
Apoptotic Bodies ◽  
Limited Evidence ◽  
In Vivo Models ◽  
Dose Determination

Liver fibrosis (LF) is a worldwide health problem that is associated with a range of complications and high mortality. Due to the scarcity of liver donors, mesenchymal stem cell (MSC) therapy emerged as an alternative therapeutic strategy. However, it is widely accepted that most of the transplanted MSCs exhibit their therapeutic impact mainly via a bystander paracrine (medicinal) capacity. In addition to their secretory proteins, MSCs also produce various types of extracellular vesicles (EVs) that are classified into three main subtypes: microvesicles, exosomes and apoptotic bodies. Thanks to their peculiar cargo composition (e.g., proteins, lipids, and nucleic acids), EVs serve as an advantageous candidate for cell-free therapy. Recently, MSC-derived EVs (MSC-EVs) have gained the podium due to their regenerative and immunomodulatory effect. In mitigation/treatment of LF, a plethora of recent studies have shown the anti-inflammatory, anti-fibrotic and cytoprotective effects of both MSCs and MSC-EVs in various in vitro and in vivo models of LF. However, despite the limited evidence, we sought in this mini review to sort out the established data and formulate several challenging questions that must be answered to pave the way for further clinical applications. One of the major questions to ask is “Which is the best therapeutic approach, MSCs or MSC-EVs?” We tried to highlight how difficult it might be to compare the two approaches while our understanding of both candidates is still deficient. Among the major obstacles against such comparison is the inaccurate equivalent dose determination, the unknown in vivo behavior, and the undetermined lifespan/fate of each. Currently, the fields of MSCs and MSC-EVs seem to be rich in ideas but lacking in appropriate technologies to test these ideas. Nevertheless, continuous efforts are likely to help resolve some of the challenges listed here.

scholarly journals The influence of a new water infrastructure development on the relative abundance of two Australian freshwater turtle species

2018 ◽  
Vol 66 (1) ◽  
pp. 57 ◽  
Author(s):  
Natalie J. Clark ◽  
Courtenay E. Mills ◽  
Nicolette A. Osborne ◽  
Kerry M. Neil
Keyword(s):  
Relative Abundance ◽  
Temporal Variability ◽  
Monitoring Program ◽  
Freshwater Turtle ◽  
Spatial And Temporal Variability ◽  
Main Body ◽  
Water Infrastructure ◽  
Turtle Species ◽  
Australian Freshwater ◽  
The Impact

Development of water infrastructure benefits water security and agriculture but poses risks to habitat and aquatic fauna. Wyaralong Dam was constructed on Teviot Brook in 2010 to provide future urban water supplies for South East Queensland, Australia. Construction of the dam created a large impoundment area and environmental impact assessment predicted significant impacts upon resident freshwater turtle species and their habitats. Differences in habitat requirements, life-history characteristics and sensitivity to change between the Macquarie River turtle (Emydura macquarii macquarii) and the common saw-shelled turtle (Myuchelys latisternum) were expected to influence the impact of the dam on the spatial and temporal abundance of these species. The relative abundance of each species was monitored at sites located within, upstream and downstream of the impoundment across wet and dry seasons during the dam’s first five years of operation. The results of this monitoring program indicate that spatial and temporal variability in the relative abundance of E. macquarii macquarii and M. latisternum occurred during the study but not all expected impacts were realised. Contrary to expectation, the relative abundance of E. macquarii macquarii did not increase over time within, upstream or downstream of the dam. M. latisternum showed greater temporal variability at some sites; however, no clear relationship between relative abundance and operational years was observed during the monitoring program. Spatial variability in relative abundance between sites was dependent upon season, with trends generally consistent across both turtle species. Where differences between species were observed, these are suspected to have resulted from the influence of environmental conditions on species-specific movement behaviours. The monitoring program confirmed the use of the upper limits of the impoundment and the plunge pool below the dam wall by both turtle species but relative abundance within the main body of the impoundment remained low throughout monitoring. The results of the study allow for consideration of the suitability of predefined management measures and the development of recommendations for future monitoring programs prescribed for water infrastructure developments.

The Structure of the Male Genital System of the Port Jackson Shark, Heterodontus portujacksoni, with Particular reference to the Genital Ducts

1982 ◽  
Vol 30 (4) ◽  
pp. 523 ◽  
Author(s):  
N Jones ◽  
RC Jones
Keyword(s):  
Sertoli Cell ◽  
Initial Segment ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
Terminal Segment ◽  
Rete Testis ◽  
Ductuli Efferentes ◽  
Pseudostratified Epithelium ◽  
Port Jackson ◽  
Germinal Cells

The testes of H. portusjacksoni are paired cylindrical organs with a germinal ridge running longitudinally along the ventral surface. The latter produces ampullae which contain Sertoli and germinal cells, and which migrate dorsally as spermatogenesis proceeds. They evacuate near the dorsal surface of the testis to release spermatozoa, large oval eosinophilic bodies (Sertoli cell bodies) and small eosinophilic particles. All of the genital ducts are lined by a ciliated epithelium. In the rete testis it is a low columnar type; the ducts consist of the conducting tubules, which convey ampullae across the testis, and the longitudinal testis canal, which runs along the dorsal surface of the testis. Six ductuli efferentes (lined by a low pseudostratified columnar epithelium) leave the testis, course dorsally through the epigonal organ and mesorchium, and enter the epididymis. Subsequently, pairs of ductuli efferentes successively join together to form a short common ductulus efferent which then continues as the ductus epididymidis. The latter has two structurally distinct regions: the initial segment is a narrow, convoluted, pigmented duct with a very tall pseudostratified epithelium; the terminal segment is wider than the initial segment, unpigmented and lined by a low pseudostratified epithelium. It is very convoluted proximally, but widens and becomes less convoluted distally; its distal 5 cm (ampulla of ductus epididymidis) is straight and contains a muscular wall. Very few Sertoli cell bodies are present in the terminal segment of the ductus epididymidis. However, except for the ampullary region the duct receives secretions (including irregularly shaped eosinophilic bodies) from Leydig's gland (a series of branched tubular glands). Secretions from these glands seem to be involved in the formation of spermatozoa into spherical bundles. The structure of the clasper and siphon are assessed in terms of their function and significance for taxonomical purposes.

scholarly journals Population status and distribution of freshwater turtles in Taiwan

Oryx ◽  
2010 ◽  
Vol 44 (2) ◽  
pp. 261-266 ◽  
Author(s):  
Tien-Hsi Chen ◽  
Kuang-Yang Lue
Keyword(s):  
Native Species ◽  
Mainland China ◽  
Iucn Red List ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Chinese Market ◽  
Negative Effects ◽  
Turtle Species ◽  
Mauremys Mutica ◽  
Effective Conservation

AbstractBecause of burgeoning demand in the Chinese market and extensive habitat loss more than half of the freshwater turtle and tortoise species in Asia are categorized as Endangered or Critically Endangered on the IUCN Red List. To investigate the distribution and status of the native freshwater turtle species of Taiwan a trapping programme was conducted during 2001–2007, yielding a total of 1,828 individuals of four native species at 103 sites. Mauremys sinensis was the most abundant and widely distributed species; it was collected from 70 sites and accounted for 78.6% of all turtles captures. Mauremys mutica comprised 17.8% at 46 sites. Pelodiscus sinensis were captured in low numbers at 19 sites. No Mauremys reevesii were collected on the main island of Taiwan but the species was found on Kinmen Island near mainland China. Capture success was low at most sites and overall sex ratios were significantly male-biased in all species, suggesting that the freshwater turtles have suffered from the negative effects of habitat disturbance and extensive exploitation. Effective conservation measures are urgently required to ensure the viability of the native freshwater turtle species of Taiwan.

Ultrastructure of the Genital Duct Epithelium of the Male Port Jackson Shark, Heterodontus-Portusjacksoni

1992 ◽  
Vol 40 (3) ◽  
pp. 257 ◽  
Author(s):  
RC Jones ◽  
M Lin
Keyword(s):  
Endoplasmic Reticulum ◽  
Epithelial Cells ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Secretory Granules ◽  
Close Association ◽  
Ciliated Cells ◽  
Dense Bodies ◽  
Ductuli Efferentes ◽  
Apical Vesicles

The genital ducts of Heterodontus portusjacksoni are lined by a ciliated epithelium. In the ductuli efferentes the epithelium is low and contains numerous intraepithelial leucocytes which often contain large dense bodies. All epithelial cells are ciliated and are characterised by apical vesicles, vacuoles and glycogen granules, some rough endoplasmic reticulum, dense bodies and lipid droplets, and a Golgi apparatus. The initial segment of the ductus epididymidis is lined by a very tall epithelium of ciliated and non-ciliated cells. The non-ciliated cells contain numerous apical vesicles, a large Golgi apparatus and numerous mitochondria and secretory granules in close association with an extensive endoplasmic reticulum. The terminal segment of the ductus epididymidis is lined by a low columnar epithelium. A proximal region, occupying part of the head of the epididymis, is similar to the epithelium in the ductuli efferentes. Distally, all the epithelial cells are ciliated. They are characterised by considerable dilated endoplasmic reticulum, a Golgi apparatus, apical vesicles, and numerous mitochondria and secretory granules. The secretory tubules of Leydig's glands are lined by a very tall epithelium with non-ciliated cells containing extensive, dilated, rough endoplasmic reticulum, a large Golgi apparatus, and numerous mitochondria and secretory granules. The significance of the structural differentiation of the duct is discussed in relation to the evolution of the mammalian epididymis.

scholarly journals Histological Study of Rete Testis and Ductuli efferentes of Rabbit (Oryctolagus cuniculus)

2019 ◽  
Vol 2 ◽  
pp. 145-147
Author(s):  
Rakhmiyati Rakhmiyati ◽  
Muhammad Jafar Luthfi
Keyword(s):  
Histological Study ◽  
Rete Testis ◽  
Seminiferous Tubules ◽  
Sperm Cells ◽  
Observation Data ◽  
Thin Walls ◽  
Complex Part ◽  
Ductuli Efferentes ◽  
Pass Through ◽  
Testis Tissue

The testes produce sperm cells through the spermatogenesis process that occurs in the complex system ducts starting form seminiferous tubules to vas deferens. Testis has a very complex part to support sperm cell production. Sperm cells that have been formed through the process of spermatogenesis will move towards the lumen in the seminiferous tubules. Then the sperm cells will pass through the rete testis tissue, then to ductuli efferentes to arrive at the epididymis for the process of maturing sperm. Anatomical studies on seminiferous tubular tissue and epididymal organs have often been carried out, but there is still very little observation data on rete testis and ductuli efferentes in rabbits. The method used in this study was the paraffin method with hematoxylin-eosin (HE) staining. The observations showed that the structure of the testicular rete channels had thin walls compared to the seminifous tubule channels. Ductuli efferens is a channel between of rete testis and epididymis.

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