WorldWideScience

Sample records for ciliated ependymal cells

  1. Myosin Id is required for planar cell polarity in ciliated tracheal and ependymal epithelial cells.

    Science.gov (United States)

    Hegan, Peter S; Ostertag, Eric; Geurts, Aron M; Mooseker, Mark S

    2015-10-01

    In wild type (WT) tracheal epithelial cells, ciliary basal bodies are oriented such that all cilia on the cell surface beat in the same upward direction. This precise alignment of basal bodies and, as a result, the ciliary axoneme, is termed rotational planar cell polarity (PCP). Rotational PCP in the multi-ciliated epithelial cells of the trachea is perturbed in rats lacking myosin Id (Myo1d). Myo1d is localized in the F-actin and basal body rich subapical cortex of the ciliated tracheal epithelial cell. Scanning and transmission electron microscopy of Myo1d knock out (KO) trachea revealed that the unidirectional bending pattern is disrupted. Instead, cilia splay out in a disordered, often radial pattern. Measurement of the alignment axis of the central pair axonemal microtubules was much more variable in the KO, another indicator that rotational PCP is perturbed. The asymmetric localization of the PCP core protein Vangl1 is lost. Both the velocity and linearity of cilia-driven movement of beads above the tracheal mucosal surface was impaired in the Myo1d KO. Multi-ciliated brain ependymal epithelial cells exhibit a second form of PCP termed translational PCP in which basal bodies and attached cilia are clustered at the anterior side of the cell. The precise asymmetric clustering of cilia is disrupted in the ependymal cells of the Myo1d KO rat. While basal body clustering is maintained, left-right positioning of the clusters is lost.

  2. [Effects of hypomagnetic fields on motility of the cilia of ependymal cells in vivo].

    Science.gov (United States)

    Sandodze, V Ia; Svanidze, I K; Didimova, E V

    1995-01-01

    The effect of reduced vertical component of geomagnetic field on motor activity of ciliate apparatus of ependymal cells in newborn rats in vivo has been studied. In has been shown that hypomagnetic field causes the inhibitory effect on the activity of ciliate apparatus up to absolute stoppage.

  3. Ubiquitin-positive inclusions in ependymal cells.

    Science.gov (United States)

    Kawanishi, Ryuta; Mizutani, Tomohiko; Yamada, Hiroshi; Minami, Masayuki; Kakimi, Shigeo; Yamada, Tsutomu; Hatori, Tsutomu; Akima, Michio

    2003-08-01

    Ubiquitin-positive inclusions (UbIs) have not been well studied in ependymal cells. Since we detected such UbIs in the central canals of the medulla and spinal cord while investigating UbIs in neurodegenerative diseases, we studied UbIs in the entire ependymal system of 42 patients with various neurological diseases and of 10 non-neurological controls. UbIs were located in the cytoplasm of the ependymal cells, and were round to oval in shape, measuring 4-11 microm in diameter. The UbIs were non-argyrophilic and undetectable by hematoxylin and eosin staining, but mildly reactive to periodic acid-Schiff staining with and without digestion. The UbIs were variably immunoreactive for anti-epithelial membrane antigen (EMA) antibody, but did not react with several other antibodies. The co-existence of ubiquitin and EMA was confirmed by confocal laser microscopy. Throughout the ependymal system, UbIs were variably found in ependymal cells as well as in subependymal cells. There was no significant difference in the overall incidence of either ependymal or subependymal UbIs between the patients with neurological diseases and controls. However, ependymal UbIs in the central canal were more frequent in the neurological disease patients than in controls, although there was no disease specificity. This is the first comprehensive report to show common occurrence of UbIs in the ependymal cells of adult human brains.

  4. Do the ependymal cells contain vasoactive intestinal polypeptide?

    Science.gov (United States)

    Kawano, H; Masuko, S

    1989-12-04

    Immunoreaction for vasoactive intestinal polypeptide (VIP) in the ependymal cells was investigated using two different commercially available polyclonal antisera for VIP. Immunostaining with an anti-VIP serum showed strong reaction products in the ependymal cells of the central canal and the third ventricle, in addition to immunoreactive neuronal elements in the spinal cord and in the suprachiasmatic nucleus. Staining of the ependymal cells was not reduced by preabsorption of the antiserum with synthetic VIP, while the immunoreactive neuronal elements disappeared. Such staining of the ependymal cells was not found using other antiserum.

  5. Spinal cord injury reveals multilineage differentiation of ependymal cells.

    Science.gov (United States)

    Meletis, Konstantinos; Barnabé-Heider, Fanie; Carlén, Marie; Evergren, Emma; Tomilin, Nikolay; Shupliakov, Oleg; Frisén, Jonas

    2008-07-22

    Spinal cord injury often results in permanent functional impairment. Neural stem cells present in the adult spinal cord can be expanded in vitro and improve recovery when transplanted to the injured spinal cord, demonstrating the presence of cells that can promote regeneration but that normally fail to do so efficiently. Using genetic fate mapping, we show that close to all in vitro neural stem cell potential in the adult spinal cord resides within the population of ependymal cells lining the central canal. These cells are recruited by spinal cord injury and produce not only scar-forming glial cells, but also, to a lesser degree, oligodendrocytes. Modulating the fate of ependymal progeny after spinal cord injury may offer an alternative to cell transplantation for cell replacement therapies in spinal cord injury.

  6. Spinal cord injury reveals multilineage differentiation of ependymal cells.

    Directory of Open Access Journals (Sweden)

    Konstantinos Meletis

    2008-07-01

    Full Text Available Spinal cord injury often results in permanent functional impairment. Neural stem cells present in the adult spinal cord can be expanded in vitro and improve recovery when transplanted to the injured spinal cord, demonstrating the presence of cells that can promote regeneration but that normally fail to do so efficiently. Using genetic fate mapping, we show that close to all in vitro neural stem cell potential in the adult spinal cord resides within the population of ependymal cells lining the central canal. These cells are recruited by spinal cord injury and produce not only scar-forming glial cells, but also, to a lesser degree, oligodendrocytes. Modulating the fate of ependymal progeny after spinal cord injury may offer an alternative to cell transplantation for cell replacement therapies in spinal cord injury.

  7. Ependymal cell contribution to scar formation after spinal cord injury is minimal, local and dependent on direct ependymal injury

    Science.gov (United States)

    Ren, Yilong; Ao, Yan; O’Shea, Timothy M.; Burda, Joshua E.; Bernstein, Alexander M.; Brumm, Andrew J.; Muthusamy, Nagendran; Ghashghaei, H. Troy; Carmichael, S. Thomas; Cheng, Liming; Sofroniew, Michael V.

    2017-01-01

    Ependyma have been proposed as adult neural stem cells that provide the majority of newly proliferated scar-forming astrocytes that protect tissue and function after spinal cord injury (SCI). This proposal was based on small, midline stab SCI. Here, we tested the generality of this proposal by using a genetic knock-in cell fate mapping strategy in different murine SCI models. After large crush injuries across the entire spinal cord, ependyma-derived progeny remained local, did not migrate and contributed few cells of any kind and less than 2%, if any, of the total newly proliferated and molecularly confirmed scar-forming astrocytes. Stab injuries that were near to but did not directly damage ependyma, contained no ependyma-derived cells. Our findings show that ependymal contribution of progeny after SCI is minimal, local and dependent on direct ependymal injury, indicating that ependyma are not a major source of endogenous neural stem cells or neuroprotective astrocytes after SCI. PMID:28117356

  8. Molecular mapping of the origin of postnatal spinal cord ependymal cells: evidence that adult ependymal cells are derived from Nkx6.1+ ventral neural progenitor cells.

    Science.gov (United States)

    Fu, Hui; Qi, Yingchuan; Tan, Min; Cai, Jun; Hu, Xuemei; Liu, Zijing; Jensen, Jan; Qiu, Mengsheng

    2003-02-10

    Recent studies have suggested that the ependymal cells lining the central canal of postnatal spinal cord possess certain properties of neural stem cells. However, the embryonic origin and developmental potential of the postnatal spinal cord ependymal cells remain to be defined. In this report, we investigated the developmental origin of postnatal spinal ependymal cells by studying the dynamic expression of several neural progenitor genes that are initially expressed in distinct domains of neuroepithelium in young embryos. At later stages of development, as the ventricular zone of the embryonic spinal cord is reduced, expression of Nkx6.1 progenitor gene is constantly detected in ependymal cells throughout chick and mouse development. Expression of other neural progenitor genes that lie either dorsal or ventral to the Nkx6.1+ domain is gradually decreased and eventually disappeared. These results suggest that the remaining neuroepithelial cells at later stages of animal life are derived from the Nkx6.1+ ventral neuroepithelial cells. Expression of Nkx6.1 in the remaining neuroepithelium is closely associated with, and regulated by, Shh expression in the floor plate. In addition, we suggested that the Nkx6.1+ ependymal cells in adult mouse spinal cords may retain the proliferative property of neural stem cells.

  9. Vasoactive intestinal polypeptide (VIP) immunoreactivity in the ependymal cells of the rat spinal cord.

    Science.gov (United States)

    Chung, K; Lee, W T

    1988-12-19

    Vasoactive intestinal polypeptide (VIP) was demonstrated immunohistochemically in the entire ependymal and subependymal cells in all levels (cervical: C, thoracic: T, lumbar: L and sacral: S) of normal adult rat spinal cord. The VIP-immunoreactive basal processes from the apical ependymal cells coursed dorsally or ventrally along the median plane and reached the pia mater of the dorsal and ventral median septa. Many VIP-immunoreactive basal processes terminated on the blood vessels in the neuropil around the central canal. A few microvilli of the ependymal cells that project into the central canal also demonstrated intense VIP immunoreactivity. These observations suggest that ependymal cells may be involved in the modulation of VIP levels in the cerebrospinal fluid and regulation of vascular tone of the blood vessels in the spinal cord.

  10. Biciliated ependymal cell proliferation contributes to spinal cord growth.

    Science.gov (United States)

    Alfaro-Cervello, Clara; Soriano-Navarro, Mario; Mirzadeh, Zaman; Alvarez-Buylla, Arturo; Garcia-Verdugo, Jose Manuel

    2012-10-15

    Two neurogenic regions have been described in the adult brain, the lateral ventricle subventricular zone and the dentate gyrus subgranular zone. It has been suggested that neural stem cells also line the central canal of the adult spinal cord. Using transmission and scanning electron microscopy and immunostaining, we describe here the organization and cell types of the central canal epithelium in adult mice. The identity of dividing cells was determined by 3D ultrastructural reconstructions of [(3) H]thymidine-labeled cells and confocal analysis of bromodeoxyuridine labeling. The most common cell type lining the central canal had two long motile (9+2) cilia and was vimentin+, CD24+, FoxJ1+, Sox2+, and CD133+, but nestin- and glial fibrillary acidic protein (GFAP)-. These biciliated ependymal cells of the central canal (Ecc) resembled E2 cells of the lateral ventricles, but their basal bodies were different from those of E2 or E1 cells. Interestingly, we frequently found Ecc cells with two nuclei and four cilia, suggesting they are formed by incomplete cytokinesis or cell fusion. GFAP+ astrocytes with a single cilium and an orthogonally oriented centriole were also observed. The majority of dividing cells corresponded to biciliated Ecc cells. Central canal proliferation was most common during the active period of spinal cord growth. Pairs of labeled Ecc cells were observed within the central canal in adult mice 2.5 weeks post labeling. Our work suggests that the vast majority of postnatal dividing cells in the central canal are Ecc cells and their proliferation is associated with the growth of the spinal cord.

  11. Ependymal cell proliferation and apoptosis following acute spinal cord injury in the adult rat

    Institute of Scientific and Technical Information of China (English)

    Xu Wang; Jun Qian; Yanchao Ma; Guoxin Nan; Shuanke Wang; Yayi Xia; Youcheng Zhang

    2008-01-01

    BACKGROUND: Studies have reported that spinal cord injury can induce the reactive proliferation of ependymal cells and secondarily cause the apoptosis of nerve cells. However, there is no generally accepted theory on the apoptotic characteristics of ependymal cells in the injured spinal cord.OBJECTIVE: To observe the reactive proliferation and apoptosis of ependymal cells in adult rats following acute spinal cord injury.DESIGN, TIME AND SETTING: A randomized control study based on neuropathology was performed in the Third Military Medical University of Chinese PLA between 2005 and 2007.MATERIALS: Forty healthy, adult, Wistar rats were included in the present study.METHODS: Moderate spinal cord injury was established in twenty rats using Feeney's method, while the remaining 20 rats served as controls and were only treated with laminectomy. All rats were injected intraperitoneally with 1.25 mL of BrdU solution (10 mg BrdU/mL saline) 3 times at 4 hours intervals during the 12 hours prior to sacrifice.MAIN OUTCOME MEASURES: Ependymal cell proliferation and apoptosis in the rat spinal cord were determined by BrdU and nestin immunofluorescence double-labeling, as well as the TUNEL method, at 1, 3, 7, and 14 days after operation.RESULTS: In the moderate spinal cord injury rats, nestin expression was observed in the cytoplasm of ependymal cells. One day immediately following surgery, ependymal cells were BrdU-labeled. The number of BrdU-positive cells increased at 3 days, reached a peak at 7 days, and gradually reduced thereafter. The ependyma developed ti'om a constitutive monolayer cells to a multi-layer cell complex. Some BrdU/Nestin double-positive ependymal cells migrated out from the ependyma. TUNEL-positive cells were also detected in the ependyma in the central region, as well as ischemic regions of the injured spinal cord. In addition, TUNEL-positive cells were visible in the ependyma. No TUNEL-positive ependymal cells were observed in the normal spinal cord

  12. Upregulated and prolonged differentiation potential of the ependymal cells lining the ventriculus terminalis in human fetuses.

    Science.gov (United States)

    Song, Dae Yong; Cho, Byung Pil; Choi, Byoung Young; Yang, Young Chul; Lee, Bong Hee; Lim, Chang Kyo; Kang, Ho Suck

    2005-09-23

    The ventriculus terminalis (VT) is a dilated cavity within the conus medullaris of the spinal cord. Although the VT was discovered in the mid-nineteenth century, little is known about its characteristics during development in human fetuses. Ependymal cells lining the cavities within the CNS retain high differentiation potential, and are believed to be responsible for the postnatal neurogenesis. To evaluate the differentiation capacity of the ependymal cells lining the VT during development, we examined glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) expression in the spinal cord of 18-24-week-old human fetuses. GFAP is a marker for the degree of ependymal cell differentiation in the human fetus, and PCNA is a well-known marker for cell division. Morphological characteristics of the VT were also examined. At the lower portion of the conus medullaris, the central canal abruptly expands dorsally to become the VT. Then the VT widens bilaterally while its anteroposterior diameter reduces gradually in a caudal direction. Finally, the VT becomes a narrow, transverse slit at the level of the lowermost conus medullaris. Compared with those lining the central canal, more numerous ependymal cells lining the VT showed more intensive GFAP and PCNA expression throughout all gestational ages examined. This suggests that, in the developing human spinal cord, ependymal cells lining the VT retain their differentiation potential, including a higher proliferative capacity, until a later stage of development than those lining the central canal.

  13. Cellular organization of the central canal ependymal zone, a niche of latent neural stem cells in the adult mammalian spinal cord.

    Science.gov (United States)

    Hamilton, L K; Truong, M K V; Bednarczyk, M R; Aumont, A; Fernandes, K J L

    2009-12-15

    A stem cell's microenvironment, or "niche," is a critical regulator of its behaviour. In the adult mammalian spinal cord, central canal ependymal cells possess latent neural stem cell properties, but the ependymal cell niche has not yet been described. Here, we identify important similarities and differences between the central canal ependymal zone and the forebrain subventricular zone (SVZ), a well-characterized niche of neural stem cells. First, direct immunohistochemical comparison of the spinal cord ependymal zone and the forebrain SVZ revealed distinct patterns of neural precursor marker expression. In particular, ependymal cells in the spinal cord were found to be bordered by a previously uncharacterized sub-ependymal layer, which is relatively less elaborate than that of the SVZ and comprised of small numbers of astrocytes, oligodendrocyte progenitors and neurons. Cell proliferation surrounding the central canal occurs in close association with blood vessels, but unlike in the SVZ, involves mainly ependymal rather than sub-ependymal cells. These proliferating ependymal cells typically self-renew rather than produce transit-amplifying progenitors, as they generate doublets of progeny that remain within the ependymal layer and show no evidence of a lineage relationship to sub-ependymal cells. Interestingly, the dorsal pole of the central canal was found to possess a sub-population of tanycyte-like cells that express markers of both ependymal cells and neural precursors, and their presence correlates with higher numbers of dorsally proliferating ependymal cells. Together, these data identify key features of the spinal cord ependymal cell niche, and suggest that dorsal ependymal cells possess the potential for stem cell activity. This work provides a foundation for future studies aimed at understanding ependymal cell regulation under normal and pathological conditions.

  14. Neuronal nitric oxide synthase immunoreactivity in ependymal cells during early postnatal development.

    Science.gov (United States)

    Soygüder, Zafer; Karadağ, Hüseyin; Nazli, Mümtaz

    2004-03-01

    Neuronal nitric oxide synthase (nNOS) immunoreactivity was observed in ependymal cell layer of the central canal of spinal cord of neonatal rats (2-20 days old). Neuronal nitric oxide synthase immunoreactivity was present in postnatal day 2 and this immunoreactivity gradually disappeared by postnatal day 16. The progressive decrease in nNOS staining with the increasing postnatal age may suggest that nNOS staining paralleled the maturation of the central canal and may also suggest that nNOS activity plays a role in the development of the ependymal cells.

  15. Ependymal cell reactions in spinal cord segments after compression injury in adult rat.

    Science.gov (United States)

    Takahashi, Masaki; Arai, Yasuhisa; Kurosawa, Hisashi; Sueyoshi, Noriyoshi; Shirai, Shunichi

    2003-02-01

    Recently, it has been suggested that neural stem cells and neural progenitor cells exist in the ependyma that forms the central canal of the spinal cord. In this study, we produced various degrees of thoracic cord injury in adult rats using an NYU-weight-drop device, assessed the degree of recovery of lower limb motor function based on a locomotor rating scale, and analyzed the kinetics of ependymal cell proliferation and differentiation by proliferating cell nuclear antigen (PCNA), nestin, glial fibrillary acidic protein (GFAP), or GAP-43 immunostaining. The results showed that the time course of the ependymal cell proliferation and differentiation reactions differed according to the severity of injury, and that the responses occurred not only in the neighborhood of the injury but in the entire spinal cord. An increase in the locomotor rating score was related to an increase in the number of PCNA-positive cells, and the differentiation of ependymal cells into reactive astrocytes was involved in injury repair. No apoptotic cells in the ependyma were detectable by the TUNEL method. These results indicate that the ependymal cells of the spinal central canal are themselves multipotent, can divide and proliferate according to the severity of injury, and differentiate into reactive astrocytes within the ependyma without undergoing apoptosis or cell death.

  16. GABAergic responses of mammalian ependymal cells in the central canal neurogenic niche of the postnatal spinal cord.

    Science.gov (United States)

    Corns, Laura F; Deuchars, Jim; Deuchars, Susan A

    2013-10-11

    The area surrounding the central canal of the postnatal mammalian spinal cord is a highly plastic region that exhibits many similarities to other postnatal neurogenic niches, such as the subventricular zone. Within this region, ependymal cells have been identified as neural stem cells however very little is known about their properties and how the local environment, including neurotransmitters, is capable of affecting them. The neurotransmitter GABA is present around the central canal and is known to affect cells within other postnatal neurogenic niches. This study used whole cell patch clamp electrophysiology and intracellular dye-loading in in vitro Wistar rat spinal cord slices to characterise ependymal cells and their ability to respond to GABA. Ependymal cells were defined by their passive response properties and low input resistances. Extensive dye-coupling was observed between ependymal cells; this was confirmed as gap junction coupling using the gap junction blocker, 18β-glycyrrhetinic acid, which significantly increased the input resistance of ependymal cells. GABA depolarised all ependymal cells tested; the partial antagonism of this response by bicuculline and gabazine indicates that GABA(A) receptors contribute to this response. A lack of effect by baclofen suggests that GABA(B) receptors do not contribute to the GABAergic response. The ability of ependymal cells to respond to GABA suggests that GABA could be capable of influencing the proliferation and differentiation of cells within the neurogenic niche of the postnatal spinal cord.

  17. Adult spinal cord ependymal layer: a promising pool of quiescent stem cells to treat spinal cord injury

    OpenAIRE

    Panayiotou, Elena; Malas, Stavros

    2013-01-01

    Spinal cord injury (SCI) is a major health burden and currently there is no effective medical intervention. Research performed over the last decade revealed that cells surrounding the central canal of the adult spinal cord and forming the ependymal layer acquire stem cell properties either in vitro or in response to injury. Following SCI activated ependymal cells generate progeny cells which migrate to the injury site but fail to produce the appropriate type of cells in sufficient number to l...

  18. Adult spinal cord ependymal layer: A promising pool of quiescent stem cells to treat spinal cord injury

    OpenAIRE

    Stavros eMalas; Elena ePanayiotou

    2013-01-01

    Spinal cord injury is a major health burden and currently there is no effective medical intervention. Research performed over the last decade revealed that cells surrounding the central canal of the adult spinal cord and forming the ependymal layer acquire stem cell properties either in vitro or in response to injury. Following spinal cord injury activated ependymal cells generate progeny cells which migrate to the injury site but fail to produce the appropriate type of cells in sufficient nu...

  19. Adult spinal cord ependymal layer: A promising pool of quiescent stem cells to treat spinal cord injury

    Directory of Open Access Journals (Sweden)

    Stavros eMalas

    2013-11-01

    Full Text Available Spinal cord injury is a major health burden and currently there is no effective medical intervention. Research performed over the last decade revealed that cells surrounding the central canal of the adult spinal cord and forming the ependymal layer acquire stem cell properties either in vitro or in response to injury. Following spinal cord injury activated ependymal cells generate progeny cells which migrate to the injury site but fail to produce the appropriate type of cells in sufficient number to limit the damage, rendering this physiological response mainly ineffective. Research is now focusing on the manipulation of ependymal cells to produce cells of the oligodendrocyte lineage which are primarily lost in such a situation leading to secondary neuronal degeneration. Thus, there is a need for a more focused approach to understand the molecular properties of adult ependymal cells in greater detail and develop effective strategies for guiding their response during spinal cord injury.

  20. Adult spinal cord ependymal layer: a promising pool of quiescent stem cells to treat spinal cord injury.

    Science.gov (United States)

    Panayiotou, Elena; Malas, Stavros

    2013-11-28

    Spinal cord injury (SCI) is a major health burden and currently there is no effective medical intervention. Research performed over the last decade revealed that cells surrounding the central canal of the adult spinal cord and forming the ependymal layer acquire stem cell properties either in vitro or in response to injury. Following SCI activated ependymal cells generate progeny cells which migrate to the injury site but fail to produce the appropriate type of cells in sufficient number to limit the damage, rendering this physiological response mainly ineffective. Research is now focusing on the manipulation of ependymal cells to produce cells of the oligodendrocyte lineage which are primarily lost in such a situation leading to secondary neuronal degeneration. Thus, there is a need for a more focused approach to understand the molecular properties of adult ependymal cells in greater detail and develop effective strategies for guiding their response during SCI.

  1. Ependymal tumors.

    Science.gov (United States)

    Moynihan, Timothy J

    2003-12-01

    Ependymal tumors are rare malignancies that arise from the cells that line the ventricles and central canal of the spinal cord. Although they are more common in children, adults may also be effected by ependymal tumors. Prognosis is dependent on tumor location, histology, especially for myxopapillary tumors that tend to occur in the lumbar spine, extent of surgical resection, and stage of disease. Standard therapy consists of complete resection when feasible. The exact role of adjuvant radiotherapy in patients with radiographically confirmed complete resection is poorly defined. Patients with known residual disease may benefit from local radiation therapy, but the extent of radiation field and total dose are controversial. Even in patients treated with involved field radiotherapy, most relapses occur within the original tumor bed, thus local control remains the biggest obstacle to effective therapy. Chemotherapy has little impact against this tumor and has no role in the adjuvant setting, outside of a well designed clinical trial, with the possible exception of children younger than 5 years in an effort to delay radiation. A minority of patients may respond to one of several chemotherapy regimens at the time of recurrence, but the impact of this therapy is limited. Newer treatment strategies are needed.

  2. Novel observations on the origin of ependymal cells in the ventricular zone of the rat spinal cord.

    Science.gov (United States)

    Sevc, Juraj; Daxnerová, Zuzana; Haňová, Viera; Koval', Ján

    2011-02-01

    Despite extensive investigations of gliogenesis, the time of origin of ependymal cells in the spinal cord has not yet been fully elucidated. Using a single dose of 5-bromo-2-deoxyuridine combined with various survival times we monitored: mitotic activity (short survival time), the presence of newly formed cells in the ventricular zone (intermediate survival time) and the formation of ependymal cells (long survival time) during the late embryonic and early postnatal development in the ventricular zone of the spinal cord of rats. In the period of study it was found that the ependymal cells populated this region in two waves. Most of the ependymal cells originated around embryonic day 18 and then between postnatal days 8 and 15. In addition, it was observed that in the ventricular zone of the spinal cord, proliferation and production of ependymal cells continues at the slower rate at least until day 36 of postnatal development. Elucidation of the relationship between progenitors in the embryonic ventricular zone and the relative quiescent ependymal lining of the central canal in adulthood could be important in the search for the adult neural stem cell niche.

  3. Central canal ependymal cells proliferate extensively in response to traumatic spinal cord injury but not demyelinating lesions.

    Science.gov (United States)

    Lacroix, Steve; Hamilton, Laura K; Vaugeois, Alexandre; Beaudoin, Stéfanny; Breault-Dugas, Christian; Pineau, Isabelle; Lévesque, Sébastien A; Grégoire, Catherine-Alexandra; Fernandes, Karl J L

    2014-01-01

    The adult mammalian spinal cord has limited regenerative capacity in settings such as spinal cord injury (SCI) and multiple sclerosis (MS). Recent studies have revealed that ependymal cells lining the central canal possess latent neural stem cell potential, undergoing proliferation and multi-lineage differentiation following experimental SCI. To determine whether reactive ependymal cells are a realistic endogenous cell population to target in order to promote spinal cord repair, we assessed the spatiotemporal dynamics of ependymal cell proliferation for up to 35 days in three models of spinal pathologies: contusion SCI using the Infinite Horizon impactor, focal demyelination by intraspinal injection of lysophosphatidylcholine (LPC), and autoimmune-mediated multi-focal demyelination using the active experimental autoimmune encephalomyelitis (EAE) model of MS. Contusion SCI at the T9-10 thoracic level stimulated a robust, long-lasting and long-distance wave of ependymal proliferation that peaked at 3 days in the lesion segment, 14 days in the rostral segment, and was still detectable at the cervical level, where it peaked at 21 days. This proliferative wave was suppressed distal to the contusion. Unlike SCI, neither chemical- nor autoimmune-mediated demyelination triggered ependymal cell proliferation at any time point, despite the occurrence of demyelination (LPC and EAE), remyelination (LPC) and significant locomotor defects (EAE). Thus, traumatic SCI induces widespread and enduring activation of reactive ependymal cells, identifying them as a robust cell population to target for therapeutic manipulation after contusion; conversely, neither demyelination, remyelination nor autoimmunity appears sufficient to trigger proliferation of quiescent ependymal cells in models of MS-like demyelinating diseases.

  4. Central canal ependymal cells proliferate extensively in response to traumatic spinal cord injury but not demyelinating lesions.

    Directory of Open Access Journals (Sweden)

    Steve Lacroix

    Full Text Available The adult mammalian spinal cord has limited regenerative capacity in settings such as spinal cord injury (SCI and multiple sclerosis (MS. Recent studies have revealed that ependymal cells lining the central canal possess latent neural stem cell potential, undergoing proliferation and multi-lineage differentiation following experimental SCI. To determine whether reactive ependymal cells are a realistic endogenous cell population to target in order to promote spinal cord repair, we assessed the spatiotemporal dynamics of ependymal cell proliferation for up to 35 days in three models of spinal pathologies: contusion SCI using the Infinite Horizon impactor, focal demyelination by intraspinal injection of lysophosphatidylcholine (LPC, and autoimmune-mediated multi-focal demyelination using the active experimental autoimmune encephalomyelitis (EAE model of MS. Contusion SCI at the T9-10 thoracic level stimulated a robust, long-lasting and long-distance wave of ependymal proliferation that peaked at 3 days in the lesion segment, 14 days in the rostral segment, and was still detectable at the cervical level, where it peaked at 21 days. This proliferative wave was suppressed distal to the contusion. Unlike SCI, neither chemical- nor autoimmune-mediated demyelination triggered ependymal cell proliferation at any time point, despite the occurrence of demyelination (LPC and EAE, remyelination (LPC and significant locomotor defects (EAE. Thus, traumatic SCI induces widespread and enduring activation of reactive ependymal cells, identifying them as a robust cell population to target for therapeutic manipulation after contusion; conversely, neither demyelination, remyelination nor autoimmunity appears sufficient to trigger proliferation of quiescent ependymal cells in models of MS-like demyelinating diseases.

  5. Genetic deletion of afadin causes hydrocephalus by destruction of adherens junctions in radial glial and ependymal cells in the midbrain.

    Directory of Open Access Journals (Sweden)

    Hideaki Yamamoto

    Full Text Available Adherens junctions (AJs play a role in mechanically connecting adjacent cells to maintain tissue structure, particularly in epithelial cells. The major cell-cell adhesion molecules at AJs are cadherins and nectins. Afadin binds to both nectins and α-catenin and recruits the cadherin-β-catenin complex to the nectin-based cell-cell adhesion site to form AJs. To explore the role of afadin in radial glial and ependymal cells in the brain, we generated mice carrying a nestin-Cre-mediated conditional knockout (cKO of the afadin gene. Newborn afadin-cKO mice developed hydrocephalus and died neonatally. The afadin-cKO brain displayed enlarged lateral ventricles and cerebral aqueduct, resulting from stenosis of the caudal end of the cerebral aqueduct and obliteration of the ventral part of the third ventricle. Afadin deficiency further caused the loss of ependymal cells from the ventricular and aqueductal surfaces. During development, radial glial cells, which terminally differentiate into ependymal cells, scattered from the ventricular zone and were replaced by neurons that eventually covered the ventricular and aqueductal surfaces of the afadin-cKO midbrain. Moreover, the denuded ependymal cells were only occasionally observed in the third ventricle and the cerebral aqueduct of the afadin-cKO midbrain. Afadin was co-localized with nectin-1 and N-cadherin at AJs of radial glial and ependymal cells in the control midbrain, but these proteins were not concentrated at AJs in the afadin-cKO midbrain. Thus, the defects in the afadin-cKO midbrain most likely resulted from the destruction of AJs, because AJs in the midbrain were already established before afadin was genetically deleted. These results indicate that afadin is essential for the maintenance of AJs in radial glial and ependymal cells in the midbrain and is required for normal morphogenesis of the cerebral aqueduct and ventral third ventricle in the midbrain.

  6. Ependymal cells of the filum terminale in fish (Poecilia sphenops) adapted to freshwater and saltwater: electron microscopic study.

    Science.gov (United States)

    Kriebel, R M

    1981-09-01

    The ependymal lining of the central canal of the filum terminale and spinal cord in the vicinity of the caudal neurosecretory system in P. sphenops was examined in this study. Two general cell types based on shape and location were observed in the ependymal lining: cuboidal ependyma located in dorsal aspects of the filum terminal and columnar to pseudostratified ependymal cells found in ventrolateral and ventral aspects of the filum terminale. Comparison of the ependymal lining was made in animals adapted to saltwater and freshwater. In animals adapted to saltwater there was an increase in the basal infolding of the cell membrane of the dorsal cuboidal ependyma. Infolding of the basal cell membrane is a phenomenon shared by cells known to participate in transport of electrolytes. Since a possible functional relationship between the ependyma of the third ventricle and median eminence has been shown, in future studies on the osmoregulatory function of the caudal neurosecretory system the ependymal lining of the central canal in this region should be considered.

  7. ATF3 is a novel nuclear marker for migrating ependymal stem cells in the rat spinal cord.

    Science.gov (United States)

    Mladinic, Miranda; Bianchetti, Elena; Dekanic, Ana; Mazzone, Graciela L; Nistri, Andrea

    2014-05-01

    The present study identified ATF3 as a novel dynamic marker for ependymal stem/progenitor cells (nestin, vimentin and SOX2 positive) around the central canal of the neonatal or adult rat spinal cord. While quiescent ependymal cells showed cytoplasmic ATF3 expression, during 6-24h in vitro these cells mobilized and acquired intense nuclear ATF3 staining. Their migratory pattern followed a centrifugal pathway toward the dorsal and ventral funiculi, reminiscent of the rostral migratory stream of the brain subventricular stem cells. Thus, the chain cell formation was, by analogy, termed funicular migratory stream (FMS). The FMS process preceded the strong proliferation of ependymal cells occurring only after 24h in vitro. Pharmacological inhibition of MAPK-p38 and JNK/c-Jun (upstream effectors of ATF3 activation) prevented the FMS mobilization of ATF3 nuclear-positive cells. Excitotoxicity or ischemia-like conditions, reported to evoke neuronal and glial injury, did not further enhance migration of ependymal cells at 24h, suggesting that, at this early stage of damage, the FMS phenomenon had peaked and that more extensive repair processes are delayed beyond this time point. ATF3 is, therefore, useful to identify activation and migration of endogenous stem cells of the rat spinal cord in vitro.

  8. Biciliated ependymal cell proliferation contributes to spinal cord growth

    OpenAIRE

    Alfaro-Cervello, Clara; Soriano-Navarro, Mario; Mirzadeh, Zaman; Alvarez-Buylla, Arturo; García Verdugo, José Manuel

    2012-01-01

    Two neurogenic regions have been described in the adult brain, the lateral ventricle subventricular zone and the dentate gyrus subgranular zone. It has been suggested that neural stem cells also line the central canal of the adult spinal cord. Using transmission and scanning electron microscopy and immunostaining, we describe here the organization and cell types of the central canal epithelium in adult mice. The identity of dividing cells was determined by three-dimensional ultrastructural re...

  9. Spinal cord injury reveals multilineage differentiation of ependymal cells.

    OpenAIRE

    Konstantinos Meletis; Fanie Barnabé-Heider; Marie Carlén; Emma Evergren; Nikolay Tomilin; Oleg Shupliakov; Jonas Frisén

    2008-01-01

    Author Summary Spinal cord injuries occur in more than 30.000 individuals each year worldwide and result in significant morbidity, with patients requiring long physical and medical care. The recent identification of resident stem cells in the adult spinal cord has opened up for the possibility of pharmacological manipulation of these cells to produce cell types promoting recovery after injury. We have employed genetic tools to specifically address the identity and reaction to injury of a spin...

  10. Proliferation, migration, and differentiation of endogenous ependymal region stem/progenitor cells following minimal spinal cord injury in the adult rat.

    Science.gov (United States)

    Mothe, A J; Tator, C H

    2005-01-01

    Ependymal cells of the adult mammalian spinal cord exhibit stem/progenitor cell properties following injury. In the present study, we utilized intraventricular injection of 1,1'-dioctadecyl-6,6'-di(4-sulfophenyl)-3,3,3',3'-tetramethylindocarbocyanine (DiI) to label the ependyma lining the central canal to allow tracking of the migration of endogenous ependymal cells and their progeny after spinal cord injury (SCI). We developed a minimal injury model that preserved the integrity of the central canal and did not interfere with ependymal cell labeling. Three days following SCI, there was an 8.6-fold increase in the proliferative labeling index of the ependymal cells at the level of the needle track based on bromodeoxyuridine labeling, compared with 1 day post-injury. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) positive cells were not detected in the ependyma or surrounding gray matter, indicating that ependymal cells do not undergo apoptosis in response to minimal injury. Nestin was rapidly induced in the ependyma by 1 day and expression peaked by 7 days post-injury. We quantitated the number and distance of ependymal cell migration following minimal injury. The number of ependymal cells migrating from the region of the central canal increased by 3 days following minimal injury and DiI-labeled glial fibrillary acidic protein expressing cells were detected 14 days post-SCI, most of which migrated within 70 microm of the region of the central canal. These results show that a minimal SCI adjacent to the ependyma is sufficient to induce an endogenous ependymal cell response where ependymal stem/progenitor cells proliferate and migrate from the region of the central canal, differentiating primarily into astrocytes.

  11. Experimental protein malnutrition as a causative factor in the histological and histochemical disruption of the ependymal cells of the third ventricla and cervical central canal of squirrel monkeys.

    Science.gov (United States)

    Sharma, S P; Manocha, S L

    1977-01-01

    The histologic disturbances of the cuboidal and columnar ependymal cells of the neonates under the extrinsic influence of maternal protein deprivation during most of the gestation period have been demonstrated in the central canal of the cervical spinal cord and III ventricle of the squirrel monkey brain. The control animals whose mothers were maintained on high protein diets showed an unbroken ependymal layer with an intact glial fiber layer and the subependymal cell plate. Taking birth-weight as an indication of the degree of malnutrition, maximum disruption of the ependymal layer was observed in those animals born around 80 g birth-weight. In the latter, most of the ependymal cells lost their characteristic arrangement and columnar shapes. The ependymal cells of the manourished animals show a marked reduction of oxidative enzyme content and relatively active glycogen metabolism as compared to the healthy controls. The significance of these changes has been discussed in the light of parallels in the embryological development and, to some extent, functions between the orinary neurons, ependymal cells of the choroid plexus, other ependymal cells and the glial cells. In this context, the changes observed in the present studies under the effect of protein malnutrition must be taken as part of overall changes experienced by various kinds of cells comprising the nervous system.

  12. Long-distance axonal regeneration in the filum terminale of adult rats is regulated by ependymal cells.

    Science.gov (United States)

    Kwiecien, Jacek M; Avram, Ronen

    2008-03-01

    Studies of regeneration of transected adult central nervous system (CNS) axons are difficult due to lack of appropriate in vivo models. In adult rats, we described filum terminale (FT), a caudal slender extension of the sacral spinal cord and an integral part of the central nervous system (CNS), to use it as a model of spinal cord injury. FT is more than 3 cm long, encompasses a central canal lined with ependymal cells surrounded by a narrow band of axons interspersed with oligodendrocytes and astrocytes but not neurons. Two weeks after the crush of FT, histological, ultrastructural, and axonal tracing studies revealed long distance descending axonal regeneration uniquely in close proximity of the ependymal cells of the central canal. Ependymal cells extended basal processes to form channels encompassing axons apparently regenerating at a rate of more than 2 mm a day. Remarkable increase of axonal sprouting was observed in the sacral spinal cord of Long Evans Shaker (LES) rats with crushed FT. FT offers an excellent model to study mechanisms of axonal regeneration regulated by ependymal cells in the adult CNS.

  13. GABAergic responses of mammalian ependymal cells in the central canal neurogenic niche of the postnatal spinal cord ☆

    OpenAIRE

    Corns, Laura F; Deuchars, Jim; Deuchars, Susan A

    2013-01-01

    The area surrounding the central canal of the postnatal mammalian spinal cord is a highly plastic region that exhibits many similarities to other postnatal neurogenic niches, such as the subventricular zone. Within this region, ependymal cells have been identified as neural stem cells however very little is known about their properties and how the local environment, including neurotransmitters, is capable of affecting them. The neurotransmitter GABA is present around the central canal and is ...

  14. Epithelial Cell Culture from Human Adenoids: A Functional Study Model for Ciliated and Secretory Cells

    Directory of Open Access Journals (Sweden)

    Claudia González

    2013-01-01

    Full Text Available Background. Mucociliary transport (MCT is a defense mechanism of the airway. To study the underlying mechanisms of MCT, we have both developed an experimental model of cultures, from human adenoid tissue of ciliated and secretory cells, and characterized the response to local chemical signals that control ciliary activity and the secretion of respiratory mucins in vitro. Materials and Methods. In ciliated cell cultures, ciliary beat frequency (CBF and intracellular Ca2+ levels were measured in response to ATP, UTP, and adenosine. In secretory cultures, mucin synthesis and secretion were identified by using immunodetection. Mucin content was taken from conditioned medium and analyzed in the presence or absence of UTP. Results. Enriched ciliated cell monolayers and secretory cells were obtained. Ciliated cells showed a basal CBF of 10.7 Hz that increased significantly after exposure to ATP, UTP, or adenosine. Mature secretory cells showed active secretion of granules containing different glycoproteins, including MUC5AC. Conclusion. Culture of ciliated and secretory cells grown from adenoid epithelium is a reproducible and feasible experimental model, in which it is possible to observe ciliary and secretory activities, with a potential use as a model to understand mucociliary transport control mechanisms.

  15. Connexin 50 Expression in Ependymal Stem Progenitor Cells after Spinal Cord Injury Activation.

    Science.gov (United States)

    Rodriguez-Jimenez, Francisco Javier; Alastrue-Agudo, Ana; Stojkovic, Miodrag; Erceg, Slaven; Moreno-Manzano, Victoria

    2015-11-06

    Ion channels included in the family of Connexins (Cx) help to control cell proliferation and differentiation of neuronal progenitors. Here we explored the role of Connexin 50 (Cx50) in cell fate modulation of adult spinal cord derived neural precursors located in the ependymal canal (epSPC). epSPC from non-injured animals showed high expression levels of Cx50 compared to epSPC from animals with spinal cord injury (SCI) (epSPCi). When epSPC or epSPCi were induced to spontaneously differentiate in vitro we found that Cx50 favors glial cell fate, since higher expression levels, endogenous or by over-expression of Cx50, augmented the expression of the astrocyte marker GFAP and impaired the neuronal marker Tuj1. Cx50 was found in both the cytoplasm and nucleus of glial cells, astrocytes and oligodendrocyte-derived cells. Similar expression patterns were found in primary cultures of mature astrocytes. In addition, opposite expression profile for nuclear Cx50 was observed when epSPC and activated epSPCi were conducted to differentiate into mature oligodendrocytes, suggesting a different role for this ion channel in spinal cord beyond cell-to-cell communication. In vivo detection of Cx50 by immunohistochemistry showed a defined location in gray matter in non-injured tissues and at the epicenter of the injury after SCI. epSPCi transplantation, which accelerates locomotion regeneration by a neuroprotective effect after acute SCI is associated with a lower signal of Cx50 within the injured area, suggesting a minor or detrimental contribution of this ion channel in spinal cord regeneration by activated epSPCi.

  16. Connexin 50 Expression in Ependymal Stem Progenitor Cells after Spinal Cord Injury Activation

    Directory of Open Access Journals (Sweden)

    Francisco Javier Rodriguez-Jimenez

    2015-11-01

    Full Text Available Ion channels included in the family of Connexins (Cx help to control cell proliferation and differentiation of neuronal progenitors. Here we explored the role of Connexin 50 (Cx50 in cell fate modulation of adult spinal cord derived neural precursors located in the ependymal canal (epSPC. epSPC from non-injured animals showed high expression levels of Cx50 compared to epSPC from animals with spinal cord injury (SCI (epSPCi. When epSPC or epSPCi were induced to spontaneously differentiate in vitro we found that Cx50 favors glial cell fate, since higher expression levels, endogenous or by over-expression of Cx50, augmented the expression of the astrocyte marker GFAP and impaired the neuronal marker Tuj1. Cx50 was found in both the cytoplasm and nucleus of glial cells, astrocytes and oligodendrocyte-derived cells. Similar expression patterns were found in primary cultures of mature astrocytes. In addition, opposite expression profile for nuclear Cx50 was observed when epSPC and activated epSPCi were conducted to differentiate into mature oligodendrocytes, suggesting a different role for this ion channel in spinal cord beyond cell-to-cell communication. In vivo detection of Cx50 by immunohistochemistry showed a defined location in gray matter in non-injured tissues and at the epicenter of the injury after SCI. epSPCi transplantation, which accelerates locomotion regeneration by a neuroprotective effect after acute SCI is associated with a lower signal of Cx50 within the injured area, suggesting a minor or detrimental contribution of this ion channel in spinal cord regeneration by activated epSPCi.

  17. SOX2 expression is upregulated in adult spinal cord after contusion injury in both oligodendrocyte lineage and ependymal cells.

    Science.gov (United States)

    Lee, Hyun Joon; Wu, Junfang; Chung, Jumi; Wrathall, Jean R

    2013-02-01

    The upregulation of genes normally associated with development may occur in the adult after spinal cord injury (SCI). To test this, we performed real-time RT-PCR array analysis of mouse spinal cord mRNAs comparing embryonic day (E)14.5 spinal cord with intact adult and adult cord 1 week after a clinically relevant standardized contusion SCI. We found significantly increased expression of a large number of neural development- and stem cell-associated genes after SCI. These included Sox2 (sex determining region Y-box 2), a transcription factor that regulates self-renewal and potency of embryonic neural stem cells and is one of only a few key factors needed to induce pluripotency. In adult spinal cord of Sox2-EGFP mice, Sox2-EGFP was found mainly in the ependymal cells of the central canal. After SCI, both mRNA and protein levels of Sox2 were significantly increased at and near the injury site. By 1 day, Sox2 was upregulated in NG2(+) oligodendrocyte progenitor cells (OPC) in the spared white matter. By 3 days, Sox2-EGFP ependymal cells had increased proliferation and begun to form multiple layers and clusters of cells in the central lesion zone of the cord. Expression of Sox2 by NG2(+) cells had declined by 1 week, but increased numbers of other Sox2-expressing cells persisted for at least 4 weeks after SCI in both mouse and rat models. Thus, SCI upregulates many genes associated with development and neural stem cells, including the key transcription factor Sox2, which is expressed in a pool of cells that persists for weeks after SCI.

  18. Central nervous system tumors with ependymal features: a broadened spectrum of primarily ependymal differentiation?

    Science.gov (United States)

    Lehman, Norman L

    2008-03-01

    Ependymomas are well-characterized central nervous system (CNS) tumors that occur most often in children and young adults. Several other CNS tumor entities, including astroblastoma, chordoid glioma, papillary tumor of the pineal region, angiocentric glioma, and pilomyxoid astrocytoma, variably display histopathologic features of ependymal differentiation. The ependymal differentiation in some of these tumors is generally accepted, whereas in others, it is controversial. This article briefly reviews ependymal cell development and conventional ependymomas, the pathologic findings and clinical behavior of tumors with variable ependymal features, and the rationales for their inclusion with ependymomas or exclusion from a larger family of ependymal tumors. These issues are addressed in the context of early morphologic insights of Bailey and Cushing, Friede, and others; contemporary oncologic concepts; and recent relevant molecular and tumor stem cell studies.

  19. Effects of histamine on ciliary beat frequency of ciliated cells from guinea pigs nasal mucosa.

    Science.gov (United States)

    An, Fengwei; Xing, Lijun; Zhang, Zhiqiang; Chen, Lei

    2015-10-01

    We aimed to investigate the effect of histamine on ciliary beat frequency (CBF) through combining high-speed digital microscopy and patch-clamp technology. Ciliated cells were obtained from septum and turbinate of 90-120-day-old healthy male guinea pigs. Tight seal was formed by applying negative pressure on the glass electrode after the drawing and pushing progress. Then, we enrolled high-speed digital microscopy to measure CBF before and after treatment with histamine of different concentrations ranging from 10(-6) to 10(-1) mol/L in Hank's solution and D-Hank's solution as well as after administrating adenosine triphosphate. One-way ANOVA, Student's t test or Kruskal-Wallis test was used for statistical comparisons. Glass electrode fix up ciliated cell is available at tip diameter of 2-5 μm and negative pressure of 10-20 cmH2O column. The baseline CBF in Hank's solution was higher than in D-Hank's solution. Treatment with 10(-6)-l0(-3) mol/L histamine of concentrations can stimulate a rise of CBF. Nevertheless, CBF in all groups decreased to baseline CBF within 20 min. Generally, 10(-2) mol/L histamine can stimulate a rise of CBF; meanwhile, the high concentration of histamine killed 50% ciliated cell. Histamine at 10(-1) mol/L killed all ciliated cells. Ciliary beating activity decreased in Ca(2+)-free solution. Moreover, adenosine triphosphate could increase CBF effectively after the stimulation effect of histamine. We construct an effective technology integrating patch-clamp technique with CBF measurements on ciliated cells. Extracellular histamine stimulation could increase CBF effectively.

  20. Ependymal alterations in sudden intrauterine unexplained death and sudden infant death syndrome: possible primary consequence of prenatal exposure to cigarette smoking

    Directory of Open Access Journals (Sweden)

    Matturri Luigi

    2010-07-01

    Full Text Available Abstract Background The ependyma, the lining providing a protective barrier and filtration system separating brain parenchyma from cerebrospinal fluid, is still inadequately understood in humans. In this study we aimed to define, by morphological and immunohistochemical methods, the sequence of developmental steps of the human ependyma in the brainstem (ventricular ependyma and thoracic spinal cord (central canal ependyma of a large sample of fetal and infant death victims, aged from 17 gestational weeks to 8 postnatal months. Additionally, we investigated a possible link between alterations of this structure, sudden unexplained fetal and infant death and maternal smoking. Results Our results demonstrate that in early fetal life the human ependyma shows a pseudostratified cytoarchitecture including many tanycytes and ciliated cells together with numerous apoptotic and reactive astrocytes in the subependymal layer. The ependyma is fully differentiated, with a monolayer of uniform cells, after 32 to 34 gestational weeks. We observed a wide spectrum of ependymal pathological changes in sudden death victims, such as desquamation, clusters of ependymal cells in the subventricular zone, radial glial cells, and the unusual presence of neurons within and over the ependymal lining. These alterations were significantly related to maternal smoking in pregnancy. Conclusions We conclude that in smoking mothers, nicotine and its derivatives easily reach the cerebrospinal fluid in the fetus, immediately causing ependymal damage. Consequently, we suggest that the ependyma should be examined in-depth first in victims of sudden fetal or infant death with mothers who smoke.

  1. Floor plate-derived sonic hedgehog regulates glial and ependymal cell fates in the developing spinal cord.

    Science.gov (United States)

    Yu, Kwanha; McGlynn, Sean; Matise, Michael P

    2013-04-01

    Cell fate specification in the CNS is controlled by the secreted morphogen sonic hedgehog (Shh). At spinal cord levels, Shh produced by both the notochord and floor plate (FP) diffuses dorsally to organize patterned gene expression in dividing neural and glial progenitors. Despite the fact that two discrete sources of Shh are involved in this process, the individual contribution of the FP, the only intrinsic source of Shh throughout both neurogenesis and gliogenesis, has not been clearly defined. Here, we have used conditional mutagenesis approaches in mice to selectively inactivate Shh in the FP (Shh(FP)) while allowing expression to persist in the notochord, which underlies the neural tube during neurogenesis but not gliogenesis. We also inactivated Smo, the common Hh receptor, in neural tube progenitors. Our findings confirm and extend prior studies suggesting an important requirement for Shh(FP) in specifying oligodendrocyte cell fates via repression of Gli3 in progenitors. Our studies also uncover a connection between embryonic Shh signaling and astrocyte-mediated reactive gliosis in adults, raising the possibility that this pathway is involved in the development of the most common cell type in the CNS. Finally, we find that intrinsic spinal cord Shh signaling is required for the proper formation of the ependymal zone, the epithelial cell lining of the central canal that is also an adult stem cell niche. Together, our studies identify a crucial late embryonic role for Shh(FP) in regulating the specification and differentiation of glial and epithelial cells in the mouse spinal cord.

  2. Dependence of reproductive rate on cell size and temperature in freshwater ciliated protozoa

    Energy Technology Data Exchange (ETDEWEB)

    Finlay, B.J.

    1977-01-01

    Reproductive rates have been calculated for ten species of ciliated protozoa in defined conditions. Interspecific double log regressions of generation time vs. cell volume have been computed at each of three temperatures (8.5/sup 0/C, 15/sup 0/C, and 20/sup 0/C) indicating a significant dependence of reproductive rate on cell size. Recorded generation times varied from 6.38 h in Vorticella microstoma at 20/sup 0/C to 1004 h in Spirostomum teres at 8.5/sup 0/C. These values correspond to a range in r/sub m/ (day)/sup -1/ of 2.607 to 0.017 and lambda (day)/sup -1/ of 13.554 to 1.017. The relationship between these data and similar published data for marine ciliates is examined and the value of such regressions in ecological studies of the protozoa is discussed.

  3. Ependymal variations in the caudal spinal cord.

    Science.gov (United States)

    Stoltenburg-Didinger, G; Bienentreu, R

    1981-01-01

    The lumbosacral spinal cord including the cauda equina was examined in 100 unselected autopsied cases of infants dying at or near term. A striking finding in 10% of these cases was the occurrence of bilateral collections of ependymal cells lying in rows on the surface of the lumbosacral cord. In another 25% the central canal was forked or duplicate. These foci were not associated with evidence of defective neural tube closure or spina bifida; the central canal was of normal length. There was no relationship between the ependymal structures and systemic clinical or pathological findings. The pathogenesis and significance of these lesions is unclear. Our observations suggest that they occur regularly and are not associated with neurological disturbances. The relationship of the ependymal cell collections to ependymomas of the caudal spinal cord is open to speculation.

  4. Cerebellar ependymal cyst in a dog.

    Science.gov (United States)

    Wyss-Fluehmann, G; Konar, M; Jaggy, A; Vandevelde, M; Oevermann, A

    2008-11-01

    An 11-week-old, male, Staffordshire Bull Terrier had a history of generalized ataxia and falling since birth. The neurologic findings suggested a localization in the cerebellum. Magnetic resonance imaging of the brain was performed. In all sequences the area of the cerebellum was almost replaced by fluid isointense to cerebrospinal fluid. A complete necropsy was performed after euthanasia. Histologically, the lesion was characterized by extensive loss of cerebellar tissue in both hemispheres and vermis. Toward the surface of the cerebellar defect, the cavity was confined by ruptured and folded membranes consisting of a layer of glial fibrillary acidic (GFAP)-positive glial cells covered multifocally by epithelial cells. Some of these cells bore apical cilia and were cytokeratin and GFAP negative, supporting their ependymal origin. The histopathologic features of our case are consistent with the diagnosis of an ependymal cyst. Its glial and ependymal nature as demonstrated by histopathologic and immunohistochemical examination differs from arachnoid cysts, which have also been reported in dogs. The origin of these cysts remains controversial, but it has been suggested that they develop during embryogenesis subsequent to sequestration of developing neuroectoderm. We speculate that the cyst could have been the result of a pre- or perinatal, possibly traumatic, insult because hemorrhage, and tissue destruction had occurred. To our knowledge, this is the first description of an ependymal cyst in the veterinary literature.

  5. The spinal cord ependymal region: a stem cell niche in the caudal central nervous system.

    Science.gov (United States)

    Hugnot, Jean Philippe; Franzen, Rachelle

    2011-01-01

    In the brain, specific signalling pathways localized in highly organized regions called niches, allow the persistence of a pool of stem and progenitor cells that generate new neurons and glial cells in adulthood. Much less is known on the spinal cord central canal niche where a sustained adult neurogenesis is not observed. Here we review our current knowledge of this caudal niche in normal and pathological situations. Far from being a simple layer of homogenous cells, this region is composed of several cell types localized at specific locations, expressing characteristic markers and with different morphologies and functions. We further report on a screen of online gene-expression databases to better define this spinal cord niche. Several genes were found to be preferentially expressed within or around the central canal region (Bmp6, CXCR4, Gdf10, Fzd3, Mdk, Nrtn, Rbp1, Shh, Sox4, Wnt7a) some of which by specific cellular subtypes. In depth characterization of the spinal cord niche constitutes a framework to make the most out of this endogenous cell pool in spinal cord disorders.

  6. Possible role of ependymal proliferation in improving experimental allergic encephalomyelitis in Lewis rats.

    Science.gov (United States)

    Mohamed, Adel; Yunus, Mohammed; Hamadain, Elgenaid; Benghuzzi, H

    2006-01-01

    Experimental autoimmune encephalomyelitis (EAE) animal models is an autoimmune demyelinating disease of the central nervous system, which is widely accepted as an animal for human multiple sclerosis (MS). Ependymal cells line the spinal canal and cerebral ventricles and proliferate in response to damage. These cells have the potential to differentiate into neural support cells. However, there is controversy as whether the response of the ependymal cells is a result of injury or repair. This study demonstrates using the rat EAE model a proliferative response of the ependymal cells occurred as a result of the disease. Interestingly, a more pronounced ependymal proliferative effect was seen in animals being fed a phase 2 enzyme inducer. The data suggests ependymal cells play a role in the post-inflammatory response of the brain and also may be involved in the remyelination process.

  7. Directed Induction of Functional Multi-ciliated Cells in Proximal Airway Epithelial Spheroids from Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Satoshi Konishi

    2016-01-01

    Full Text Available Multi-ciliated airway cells (MCACs play a role in mucociliary clearance of the lung. However, the efficient induction of functional MCACs from human pluripotent stem cells has not yet been reported. Using carboxypeptidase M (CPM as a surface marker of NKX2-1+-ventralized anterior foregut endoderm cells (VAFECs, we report a three-dimensional differentiation protocol for generating proximal airway epithelial progenitor cell spheroids from CPM+ VAFECs. These spheroids could be induced to generate MCACs and other airway lineage cells without alveolar epithelial cells. Furthermore, the directed induction of MCACs and of pulmonary neuroendocrine lineage cells was promoted by adding DAPT, a Notch pathway inhibitor. The induced MCACs demonstrated motile cilia with a “9 + 2” microtubule arrangement and dynein arms capable of beating and generating flow for mucociliary transport. This method is expected to be useful for future studies on human airway disease modeling and regenerative medicine.

  8. Calcium in ciliated protozoa: sources, regulation, and calcium-regulated cell functions.

    Science.gov (United States)

    Plattner, H; Klauke, N

    2001-01-01

    In ciliates, a variety of processes are regulated by Ca2+, e.g., exocytosis, endocytosis, ciliary beat, cell contraction, and nuclear migration. Differential microdomain regulation may occur by activation of specific channels in different cell regions (e.g., voltage-dependent Ca2+ channels in cilia), by local, nonpropagated activation of subplasmalemmal Ca stores (alveolar sacs), by different sensitivity thresholds, and eventually by interplay with additional second messengers (cilia). During stimulus-secretion coupling, Ca2+ as the only known second messenger operates at approximately 5 microM, whereby mobilization from alveolar sacs is superimposed by "store-operated Ca2+ influx" (SOC), to drive exocytotic and endocytotic membrane fusion. (Content discharge requires binding of extracellular Ca2+ to some secretory proteins.) Ca2+ homeostasis is reestablished by binding to cytosolic Ca2+-binding proteins (e.g., calmodulin), by sequestration into mitochondria (perhaps by Ca2+ uniporter) and into endoplasmic reticulum and alveolar sacs (with a SERCA-type pump), and by extrusion via a plasmalemmal Ca2+ pump and a Na+/Ca2+ exchanger. Comparison of free vs total concentration, [Ca2+] vs [Ca], during activation, using time-resolved fluorochrome analysis and X-ray microanalysis, respectively, reveals that altogether activation requires a calcium flux that is orders of magnitude larger than that expected from the [Ca2+] actually required for local activation.

  9. Connecting alveolate cell biology with trophic ecology in the marine plankton using the ciliate Favella as a model.

    Science.gov (United States)

    Echevarria, Michael L; Wolfe, Gordon V; Strom, Suzanne L; Taylor, Alison R

    2014-10-01

    Planktonic alveolates (ciliates and dinoflagellates), key trophic links in marine planktonic communities, exhibit complex behaviors that are underappreciated by microbiologists and ecologists. Furthermore, the physiological mechanisms underlying these behaviors are still poorly understood except in a few freshwater model ciliates, which are significantly different in cell structure and behavior than marine planktonic species. Here, we argue for an interdisciplinary research approach to connect physiological mechanisms with population-level outcomes of behaviors. Presenting the tintinnid ciliate Favella as a model alveolate, we review its population ecology, behavior, and cellular/molecular biology in the context of sensory biology and synthesize past research and current findings to construct a conceptual model describing the sensory biology of Favella. We discuss how emerging genomic information and new technical methods for integrating research across different levels of biological organization are paving the way for rapid advance. These research approaches will yield a deeper understanding of the role that planktonic alveolates may play in biogeochemical cycles, and how they may respond to future ocean conditions.

  10. Ultrastructure of the ciliated cells of the free-swimming larva, and sessile stages, of the marine sponge Haliclona indistincta (Demospongiae: Haplosclerida).

    Science.gov (United States)

    Stephens, Kelly M; Ereskovsky, Alexander; Lalor, Pierce; McCormack, Grace P

    2013-11-01

    We provide a detailed, comparative study of the ciliated cells of the marine haplosclerid sponge Haliclona indistincta, in order to make data available for future phylogenetic comparisons at the ultrastructural level. Our study focuses on the description and analysis of the larval epithelial cells, and choanocytes of the metamorphosed juvenile sponge. The ultrastructure of the two cell types is sufficiently different to prevent our ability to conclusively determine the origin of the choanocytes from the larval ciliated cells. However, ciliated, epithelial cells were observed in a migratory position within the inner cell mass of the larval stages. Some cilia were observed within the cell's cytoplasm, which is indicative of the ciliated epithelial cell undergoing transdifferentiation into a choanocyte; while traces of other ciliated epithelial cells were contained within phagosomes, suggesting they are phagocytosed. We compared our data with other species described in the literature. However, any phylogenetic inference must wait until further detailed comparisons can be made with species whose phylogenetic position has been determined by other means, such as phylogenomics, in order to more closely link genomic, and morphological information.

  11. : a database of ciliate genome rearrangements.

    Science.gov (United States)

    Burns, Jonathan; Kukushkin, Denys; Lindblad, Kelsi; Chen, Xiao; Jonoska, Nataša; Landweber, Laura F

    2016-01-01

    Ciliated protists exhibit nuclear dimorphism through the presence of somatic macronuclei (MAC) and germline micronuclei (MIC). In some ciliates, DNA from precursor segments in the MIC genome rearranges to form transcriptionally active genes in the mature MAC genome, making these ciliates model organisms to study the process of somatic genome rearrangement. Similar broad scale, somatic rearrangement events occur in many eukaryotic cells and tumors. The (http://oxytricha.princeton.edu/mds_ies_db) is a database of genome recombination and rearrangement annotations, and it provides tools for visualization and comparative analysis of precursor and product genomes. The database currently contains annotations for two completely sequenced ciliate genomes: Oxytricha trifallax and Tetrahymena thermophila.

  12. Ciliate Nassula sp. grazing on a microcystin-producing cyanobacterium (Planktothrix agardhii): impact on cell growth and in the microcystin fractions

    Energy Technology Data Exchange (ETDEWEB)

    Combes, Audrey; Dellinger, Marc [' Molecules de communication et adaptation des microorganismes' , UMR 7245 CNRS-MNHN, Museum national d' Histoire naturelle, CP 39, 57 rue Cuvier, F-75231 Paris Cedex 05 (France); Cadel-six, Sabrina [' Unite Caracterisation des Toxines' - Laboratoire de securite des aliments de Maisons-Alfort - ANSES, F-94701 Maisons Alfort Cedex (France); Amand, Severine [' Molecules de communication et adaptation des microorganismes' , UMR 7245 CNRS-MNHN, Museum national d' Histoire naturelle, CP 39, 57 rue Cuvier, F-75231 Paris Cedex 05 (France); Comte, Katia, E-mail: kcomte@mnhn.fr [' Molecules de communication et adaptation des microorganismes' , UMR 7245 CNRS-MNHN, Museum national d' Histoire naturelle, CP 39, 57 rue Cuvier, F-75231 Paris Cedex 05 (France)

    2013-01-15

    The proliferation of microcystins (MCs)-producing cyanobacteria (MCs) can have detrimental effects on the food chain in aquatic environments. Until recently, few studies had focused on the fate of MCs in exposed organisms, such as primary consumers of cyanobacteria. In this study, we investigate the impact of an MC-producing strain of the cyanobacterium Planktothrix agardhii on the growth and physiology of a Nassula sp. ciliate isolated from a non-toxic cyanobacterial bloom. We show that this Nassula sp. strain was able to consume and grow while feeding exclusively on an MC-producing cyanobacterium over a prolonged period of time (8 months). In short-term exposure experiments (8 days), ciliates consuming an MC-producing cyanobacterial strain displayed slower growth rate and higher levels of antioxidant enzymes than ciliates feeding on two non-MC-producing strains. Three high-performance methods (LC/MS, LC/MS-MS and ELISA) were used to quantify the free and bound MCs in the culture medium and in the cells. We show that ciliate grazing led to a marked decrease in free MCs (methanol extractable) in cells, the MCs were therefore no longer found in the surrounding culture medium. These findings suggest that MCs may have undergone redistribution (free vs bound MCs) or chemical degradation within the ciliates.

  13. Ependymal Proliferation: A Conduit for Tricking the Central Nervous System into Bioengineering Itself.

    Science.gov (United States)

    Sheikh, Amin A; Mohamed, Adel

    2015-01-01

    Ependymal Cells are a type of Glial Cell lining the ventricles and central canal of the spinal cord. Their primary function is to secrete and circulate cerebrospinal fluid (CSF). Neural stem cells (NSC) exist within the ependymal lining that are capable of neurogenesis. Historically it was thought that neurogenesis only occurred prenatally and that adult ependymal cells are incapable of regeneration. It is now known that primary neurogenic areas within the Central Nervous System (CNS) are located within the lateral ventricle and hippocampus. Recent studies have demonstrated that ependymal cells lining the central cord canal possess dormant neural stem cells capable of differentiation following Spinal Cord Injury (SCI). Recent research has focused on strategies to modulate cellular proliferation and differentiation in the spinal cord. In SCI these cells have the propensity to migrate to the site of damage and differentiate into astrocytes and oligodendrocytes. Ependymal cells are also capable of migrating into the hypothalamus and undergo proliferation. Neurological insult such as SCI leads the oxidative stress response, inflammation and subsequent activation of ependymal cells into astrocytes that are the body’s way to regenerate and heal. The presence or absence of astrocytes, neuronal growth factors, non-neuronal growth factors, microtubule and microtubule activating proteins are factors which promote cell survival and terminal differentiation of neurons.

  14. Laminin-332 alters connexin profile, dye coupling and intercellular Ca2+ waves in ciliated tracheal epithelial cells

    Directory of Open Access Journals (Sweden)

    Olsen Colin E

    2006-08-01

    Full Text Available Abstract Background Tracheal epithelial cells are anchored to a dynamic basement membrane that contains a variety of extracellular matrix proteins including collagens and laminins. During development, wound repair and disease of the airway epithelium, significant changes in extracellular matrix proteins may directly affect cell migration, differentiation and events mediated by intercellular communication. We hypothesized that alterations in cell matrix, specifically type I collagen and laminin α3β3γ2 (LM-332 proteins within the matrix, directly affect intercellular communication in ciliated rabbit tracheal epithelial cells (RTEC. Methods Functional coupling of RTEC was monitored by microinjection of the negatively charged fluorescent dyes, Lucifer Yellow and Alexa 350, into ciliated RTEC grown on either a LM-332/collagen or collagen matrix. Coupling of physiologically significant molecules was evaluated by the mechanism and extent of propagated intercellular Ca2+ waves. Expression of connexin (Cx mRNA and proteins were assayed by reverse transcriptase – polymerase chain reaction and immunocytochemistry, respectively. Results When compared to RTEC grown on collagen alone, RTEC grown on LM-332/collagen displayed a significant increase in dye transfer. Although mechanical stimulation of RTEC grown on either LM-332/collagen or collagen alone resulted in intercellular Ca2+ waves, the mechanism of transfer was dependent on matrix: RTEC grown on LM-332/collagen propagated Ca2+waves via extracellular purinergic signaling whereas RTEC grown on collagen used gap junctions. Comparison of RTEC grown on collagen or LM-332/collagen matrices revealed a reorganization of Cx26, Cx43 and Cx46 proteins. Conclusion Alterations in airway basement membrane proteins such as LM-332 can induce connexin reorganizations and result in altered cellular communication mechanisms that could contribute to airway tissue function.

  15. Genome-wide analysis of the phosphoinositide kinome from two ciliates reveals novel evolutionary links for phosphoinositide kinases in eukaryotic cells.

    Directory of Open Access Journals (Sweden)

    George Leondaritis

    Full Text Available BACKGROUND: The complexity of phosphoinositide signaling in higher eukaryotes is partly due to expansion of specific families and types of phosphoinositide kinases (PIKs that can generate all phosphoinositides via multiple routes. This is particularly evident in the PI3Ks and PIPKs, and it is considered an evolutionary trait associated with metazoan diversification. Yet, there are limited comprehensive studies on the PIK repertoire of free living unicellular organisms. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a genome-wide analysis of putative PIK genes in two free living ciliated cells, Tetrahymena and Paramecium. The Tetrahymena thermophila and Paramecium tetraurelia genomes were probed with representative kinases from all families and types. Putative homologs were verified by EST, microarray and deep RNA sequencing database searches and further characterized for domain structure, catalytic efficiency, expression patterns and phylogenetic relationships. In total, we identified and characterized 22 genes in the Tetrahymena thermophila genome and 62 highly homologues genes in Paramecium tetraurelia suggesting a tight evolutionary conservation in the ciliate lineage. Comparison to the kinome of fungi reveals a significant expansion of PIK genes in ciliates. CONCLUSIONS/SIGNIFICANCE: Our study highlights four important aspects concerning ciliate and other unicellular PIKs. First, ciliate-specific expansion of PI4KIII-like genes. Second, presence of class I PI3Ks which, at least in Tetrahymena, are associated with a metazoan-type machinery for PIP3 signaling. Third, expansion of divergent PIPK enzymes such as the recently described type IV transmembrane PIPKs. Fourth, presence of possible type II PIPKs and presumably inactive PIKs (hence, pseudo-PIKs not previously described. Taken together, our results provide a solid framework for future investigation of the roles of PIKs in ciliates and indicate that novel functions and novel regulatory

  16. Can a fermentation gas mainly produced by rumen Isotrichidae ciliates be a potential source of biohydrogen and a fuel for a chemical fuel cell?

    Science.gov (United States)

    Piela, Piotr; Michałowski, Tadeusz; Miltko, Renata; Szewczyk, Krzysztof; Sikora, Radosław; Grzesiuk, Elzbieta; Sikora, Anna

    2010-07-01

    Bacteria, fungi and protozoa inhabiting the rumen, the largest chamber of the ruminants' stomach, release large quantities of hydrogen during the fermentation of carbohydrates. The hydrogen is used by coexisting methanogens to produce methane in energy-yielding processes. This work shows, for the first time, a fundamental possibility of using a hydrogen-rich fermentation gas produced by selected rumen ciliates to feed a low-temperature hydrogen fuel cell. A biohydrogen fuel cell (BHFC) was constructed consisting of (i) a bioreactor, in which a hydrogen-rich gas was produced from glucose by rumen ciliates, mainly of the Isotrichidae family, deprived of intra- and extracellular bacteria, methanogens, and fungi, and (ii) a chemical fuel cell of the polymer-electrolyte type (PEFC). The fuel cell was used as a tester of the technical applicability of the fermentation gas produced by the rumen ciliates for power generation. The average estimated hydrogen yield was ca. 1.15 mol H2 per mol of fermented glucose. The BHFC performance was equal to the performance of the PEFC running on pure hydrogen. No fuel cell poisoning effects were detected. A maximum power density of 1.66 kW/m2 (PEFC geometric area) was obtained at room temperature. The maximum volumetric power density was 128 W/m3 but the coulombic efficiency was only ca. 3.8%. The configuration of the bioreactor limited the continuous operation time of this BHFC to ca. 14 hours.

  17. Morphogenesis of respiratory syncytial virus in human primary nasal ciliated epithelial cells occurs at surface membrane microdomains that are distinct from cilia

    Energy Technology Data Exchange (ETDEWEB)

    Jumat, Muhammad Raihan [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Yan, Yan [Department of Otolaryngology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228 (Singapore); Ravi, Laxmi Iyer [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Wong, Puisan [Detection and Diagnostics Laboratory, DSO National Laboratories, 27 Medical Drive, Singapore 117510 (Singapore); Huong, Tra Nguyen [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Li, Chunwei [Department of Otolaryngology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228 (Singapore); Tan, Boon Huan [Detection and Diagnostics Laboratory, DSO National Laboratories, 27 Medical Drive, Singapore 117510 (Singapore); Wang, De Yun [Department of Otolaryngology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228 (Singapore); Sugrue, Richard J., E-mail: rjsugrue@ntu.edu.sg [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore)

    2015-10-15

    The distribution of cilia and the respiratory syncytial virus (RSV) nucleocapsid (N) protein, fusion (F) protein, attachment (G) protein, and M2-1 protein in human ciliated nasal epithelial cells was examined at between 1 and 5 days post-infection (dpi). All virus structural proteins were localized at cell surface projections that were distinct from cilia. The F protein was also trafficked into the cilia, and while its presence increased as the infection proceeded, the N protein was not detected in the cilia at any time of infection. The presence of the F protein in the cilia correlated with cellular changes in the cilia and reduced cilia function. At 5 dpi extensive cilia loss and further reduced cilia function was noted. These data suggested that although RSV morphogenesis occurs at non-cilia locations on ciliated nasal epithelial cells, RSV infection induces changes in the cilia body that leads to extensive cilia loss. - Highlights: • Respiratory syncytial virus (RSV) infects nasal ciliated epithelial cells. • Virus morphogenesis occurs within filamentous projections distinct from cilia. • The RSV N protein was not detected in the cilia at any time during infection. • Trafficking of the F protein into the cilia occurred early in infection. • Presence of the F protein in cilia correlated with impaired cilia function.

  18. CB1 cannabinoid receptor enrichment in the ependymal region of the adult human spinal cord.

    Science.gov (United States)

    Paniagua-Torija, Beatriz; Arevalo-Martin, Angel; Ferrer, Isidro; Molina-Holgado, Eduardo; Garcia-Ovejero, Daniel

    2015-12-04

    Cannabinoids are involved in the regulation of neural stem cell biology and their receptors are expressed in the neurogenic niches of adult rodents. In the spinal cord of rats and mice, neural stem cells can be found in the ependymal region, surrounding the central canal, but there is evidence that this region is largely different in adult humans: lacks a patent canal and presents perivascular pseudorosettes, typically found in low grade ependymomas. Using Laser Capture Microdissection, Taqman gene expression assays and immunohistochemistry, we have studied the expression of endocannabinoid system components (receptors and enzymes) at the human spinal cord ependymal region. We observe that ependymal region is enriched in CB1 cannabinoid receptor, due to high CB1 expression in GFAP+ astrocytic domains. However, in human spinal cord levels that retain central canal patency we found ependymal cells with high CB1 expression, equivalent to the CB1(HIGH) cell subpopulation described in rodents. Our results support the existence of ependymal CB1(HIGH) cells across species, and may encourage further studies on this subpopulation, although only in cases when central canal is patent. In the adult human ependyma, which usually shows central canal absence, CB1 may play a different role by modulating astrocyte functions.

  19. The Spinal Ependymal Layer in Health and Disease.

    Science.gov (United States)

    Moore, S A

    2016-07-01

    Ependymal cells are epithelial support cells that line the central canal and ventricular cavities of the central nervous system, providing the interface between the cerebrospinal fluid and the parenchyma of the brain and spinal cord. The spinal ependymal layer (SEL) is composed of 3 main cell types: tanycytes, ependymocytes, and cerebrospinal fluid-contacting neurons. A fourth cell type, termed the supraependymal cell, is also occasionally described. Cells of the SEL show restricted proliferative capacity in health but display neural stem cell properties both in vitro and in vivo in various disease states. A growing body of literature is devoted to the regenerative roles of the SEL, particularly in the context of spinal cord injury, where mechanical damage to the spinal cord leads to a significant increase in SEL proliferation. SEL-derived cell progeny migrate to sites of injury within the injured spinal cord parenchyma and contribute primarily to glial scar formation. In additional to their role as endogenous neural stem cells, cells of the SEL may be an important source of cytokines and other cell signaling molecules, such as tumor necrosis factor, heat shock proteins, and various growth factors. The SEL has become of recent interest to neuroscience researchers because of its potential to participate in and respond to diseases affecting the spinal cord (eg, traumatic spinal cord injury) and neurodegenerative disease. The intimate association of the SEL with the cerebrospinal fluid makes intrathecal therapies a viable option, and recent studies highlight the potential promise of treatments that augment SEL responses to disease.

  20. Ascending central canal dilation and progressive ependymal disruption in a contusion model of rodent chronic spinal cord injury

    Directory of Open Access Journals (Sweden)

    Keirstead Hans S

    2007-09-01

    Full Text Available Abstract Background Chronic spinal cord injury (SCI can lead to an insidious decline in motor and sensory function in individuals even years after the initial injury and is accompanied by a slow and progressive cytoarchitectural destruction. At present, no pathological mechanisms satisfactorily explain the ongoing degeneration. Methods Adult female Sprague-Dawley rats were anesthetized laminectomized at T10 and received spinal cord contusion injuries with a force of 250 kilodynes using an Infinite Horizon Impactor. Animals were randomly distributed into 5 groups and killed 1 (n = 4, 28 (n = 4, 120 (n = 4, 450 (n = 5, or 540 (n = 5 days after injury. Morphometric and immunohistochemical studies were then performed on 1 mm block sections, 6 mm cranial and 6 mm caudal to the lesion epicenter. The SPSS 11.5 t test was used to determine differences between quantitative measures. Results Here, we document the first report of an ascending central canal dilation and progressive ependymal disruption cranial to the epicenter of injury in a contusion model of chronic SCI, which was characterized by extensive dural fibrosis and intraparenchymal cystic cavitation. Expansion of the central canal lumen beyond a critical diameter corresponded with ependymal cell ciliary loss, an empirically predictable thinning of the ependymal region, and a decrease in cell proliferation in the ependymal region. Large, aneurysmal dilations of the central canal were accompanied by disruptions in the ependymal layer, periependymal edema and gliosis, and destruction of the adjacent neuropil. Conclusion Cells of the ependymal region play an important role in CSF homeostasis, cellular signaling and wound repair in the spinal cord. The possible effects of this ascending pathology on ependymal function are discussed. Our studies suggest central canal dilation and ependymal region disruption as steps in the pathogenesis of chronic SCI, identify central canal dilation as a marker of

  1. Transcriptome analysis of the ependymal barrier during murine neurocysticercosis

    Directory of Open Access Journals (Sweden)

    Mishra Pramod

    2012-06-01

    Full Text Available Abstract Background Central nervous system (CNS barriers play a pivotal role in the protection and homeostasis of the CNS by enabling the exchange of metabolites while restricting the entry of xenobiotics, blood cells and blood-borne macromolecules. While the blood–brain barrier and blood-cerebrospinal fluid barrier (CSF control the interface between the blood and CNS, the ependyma acts as a barrier between the CSF and parenchyma, and regulates hydrocephalic pressure and metabolic toxicity. Neurocysticercosis (NCC is an infection of the CNS caused by the metacestode (larva of Taenia solium and a major cause of acquired epilepsy worldwide. The common clinical manifestations of NCC are seizures, hydrocephalus and symptoms due to increased intracranial pressure. The majority of the associated pathogenesis is attributed to the immune response against the parasite. The properties of the CNS barriers, including the ependyma, are affected during infection, resulting in disrupted homeostasis and infiltration of leukocytes, which correlates with the pathology and disease symptoms of NCC patients. Results In order to characterize the role of the ependymal barrier in the immunopathogenesis of NCC, we isolated ependymal cells using laser capture microdissection from mice infected or mock-infected with the closely related parasite Mesocestoides corti, and analyzed the genes that were differentially expressed using microarray analysis. The expression of 382 genes was altered. Immune response-related genes were verified by real-time RT-PCR. Ingenuity Pathway Analysis (IPA software was used to analyze the biological significance of the differentially expressed genes, and revealed that genes known to participate in innate immune responses, antigen presentation and leukocyte infiltration were affected along with the genes involved in carbohydrate, lipid and small molecule biochemistry. Further, MHC class II molecules and chemokines, including CCL12, were found

  2. Use of the PCR and fluorescent probes to recover SSU rRNA gene sequences from single cells of the ciliate protozoon Spathidium.

    Science.gov (United States)

    Dyal, P L; Hope, S; Roberts, D M; Embley, T M

    1995-08-01

    A two-stage heminested PCR approach was developed to amplify small subunit (SSU) rDNA sequences, via two overlapping fragments, from single cells of microbial eucaryotes. The method was evaluated using the ciliate protozoon Spathidium when PCR products were obtained from nine of 10 cells tested. Southern blotting demonstrated that all fragments contained the same sequence in a region of SSU rDNA which is normally highly variable between species. A fluorescent oligonucleotide probe was used to demonstrate that this sequence also occurred in fixed cells of Spathidium. Fixatives containing mercuric salts preserved cell shape and allowed probe binding with little background autofluorescence. The Spathidium sequence is closely related to that from the haptorid Homalozoon vermiculare.

  3. Response of ependymal progenitors to spinal cord injury or enhanced physical activity in adult rat.

    Science.gov (United States)

    Cizkova, Dasa; Nagyova, Miriam; Slovinska, Lucia; Novotna, Ivana; Radonak, Jozef; Cizek, Milan; Mechirova, Eva; Tomori, Zoltan; Hlucilova, Jana; Motlik, Jan; Sulla, Igor; Vanicky, Ivo

    2009-09-01

    Ependymal cells (EC) in the spinal cord central canal (CC) are believed to be responsible for the postnatal neurogenesis following pathological or stimulatory conditions. In this study, we have analyzed the proliferation of the CC ependymal progenitors in adult rats processed to compression SCI or enhanced physical activity. To label dividing cells, a single daily injection of Bromo-deoxyuridine (BrdU) was administered over a 14-day-survival period. Systematic quantification of BrdU-positive ependymal progenitors was performed by using stereological principles of systematic, random sampling, and optical Dissector software. The number of proliferating BrdU-labeled EC increased gradually with the time of survival after both paradigms, spinal cord injury, or increased physical activity. In the spinal cord injury group, we have found 4.9-fold (4 days), 7.1-fold (7 days), 4.9-fold (10 days), and 5.6-fold (14 days) increase of proliferating EC in the rostro-caudal regions, 4 mm away from the epicenter. In the second group subjected to enhanced physical activity by running wheel, we have observed 2.1-2.6 fold increase of dividing EC in the thoracic spinal cord segments at 4 and 7 days, but no significant progression at 10-14 days. Nestin was rapidly induced in the ependymal cells of the CC by 2-4 days and expression decreased by 7-14 days post-injury. Double immunohistochemistry showed that dividing cells adjacent to CC expressed astrocytic (GFAP, S100beta) or nestin markers at 14 days. These data demonstrate that SCI or enhanced physical activity in adult rats induces an endogenous ependymal cell response leading to increased proliferation and differentiation primarily into macroglia or cells with nestin phenotype.

  4. Ventricular and extraventricular ependymal tumors in 18 cats.

    Science.gov (United States)

    Woolford, L; de Lahunta, A; Baiker, K; Dobson, E; Summers, B A

    2013-03-01

    Ependymal tumors are reported rarely in domestic animals. The aims of this study were to examine the clinical and pathologic features of ventricular and extraventricular ependymomas and subependymomas in 18 domestic cats examined between 1978 and 2011. Parameters examined included age, sex, breed, clinical signs, and macroscopic and histopathologic features. The mean age of affected cats was 9 years, 4 months; median age, 8.5 years. There were 8 female and 4 male cats, and 6 cats for which sex was not recorded. Breeds included 10 domestic shorthaired, 2 domestic longhaired, 1 Persian, and 1 Siamese. Clinical signs included altered mentation or behavior, seizures, circling, propulsive gait, generalized discomfort, and loss of condition. The tumors often formed intraventricular masses and usually arose from the lining of the lateral or third ventricles, followed by the fourth ventricle, mesencephalic aqueduct, and spinal cord central canal. Three tumors were extraventricular, forming masses within the cerebrum and adjacent subarachnoid space. Histologically, 15 tumors were classified as variants of ependymomas (classic, papillary, tanycytic, or clear cell) and 3 as subependymomas. Tumors were generally well demarcated; however, 6 ependymomas focally or extensively infiltrated the adjacent neural parenchyma. Characteristic perivascular pseudorosettes were observed in all ependymomas; true rosettes were less common. Some tumors had areas of necrosis, mineralization, cholesterol clefts, and/or hemorrhage. This cohort study of feline ependymal tumors includes subependymoma and primary extraventricular ependymoma, variants not previously described in the veterinary literature but well recognized in humans.

  5. The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates human T-cell activity: involvement of interleukin-2 system.

    Science.gov (United States)

    Cervia, Davide; Catalani, Elisabetta; Belardinelli, Maria Cristina; Perrotta, Cristiana; Picchietti, Simona; Alimenti, Claudio; Casini, Giovanni; Fausto, Anna Maria; Vallesi, Adriana

    2013-02-01

    Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell-cell interaction in multi-cellular eukaryotes. This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 amino acids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases the mRNA levels of the β and γ subunits of IL-2 receptor (IL-2R), while the mRNA levels of the α subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Rα subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U-373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U-373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth.

  6. CB1 cannabinoid receptor enrichment in the ependymal region of the adult human spinal cord

    OpenAIRE

    Beatriz Paniagua-Torija; Angel Arevalo-Martin; Isidro Ferrer; Eduardo Molina-Holgado; Daniel Garcia-Ovejero

    2015-01-01

    Cannabinoids are involved in the regulation of neural stem cell biology and their receptors are expressed in the neurogenic niches of adult rodents. In the spinal cord of rats and mice, neural stem cells can be found in the ependymal region, surrounding the central canal, but there is evidence that this region is largely different in adult humans: lacks a patent canal and presents perivascular pseudorosettes, typically found in low grade ependymomas. Using Laser Capture Microdissection, Taqma...

  7. The ependymal and glial configuration in the spinal cord of urodeles.

    Science.gov (United States)

    Zamora, A J

    1978-07-17

    The structural organization of the ependymal and macroglial components of the central field of the spinal cord of postmetamorphic ribbed newts has been reinvestigated using elaborate fixation procedures for transmission electron microscopy. All along the central canal, the ependymal cells display ultrastructural features that strongly suggest a secretory activity. Infrequent mitotic images, occurring spontaneously among the ependymal cells, were observed. The tightly compacted periependymal stratum contains two types of glial cells: 1. oligodendrocytes, also observed outside this stratum as neuronal satellites, and 2. radial astrocytic cells, whose somata, exclusively located in the periependymal stratum, send their processes to the subpial lamina. The intercellular relationships between ependyma, oligodendrocytes and astrocytic cells are illustrated to show the continuity of the neuroepithelial configuration. Morphologic clues for identifying the cells of the central field of the urodele spinal cord are given. A gradient of differentiation of the oligodendroglial components could be postulated. In normal conditions, the astroglial differentiation is permanently arrested at the stage of radial glia. Some considerations concerning regeneration in the urodele spinal cord are submitted.

  8. The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates human T-cell activity: Involvement of interleukin-2 system

    Energy Technology Data Exchange (ETDEWEB)

    Cervia, Davide, E-mail: d.cervia@unitus.it [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Catalani, Elisabetta; Belardinelli, Maria Cristina [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Perrotta, Cristiana [Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Picchietti, Simona [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Alimenti, Claudio [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy); Casini, Giovanni; Fausto, Anna Maria [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Vallesi, Adriana [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy)

    2013-02-01

    Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell–cell interaction in multi-cellular eukaryotes. This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 amino acids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases the mRNA levels of the β and γ subunits of IL-2 receptor (IL-2R), while the mRNA levels of the α subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Rα subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U-373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U-373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth. -- Highlights: ► Euplotes pheromone Er-1 increases the growth of human Jurkat T-cells. ► Er-1 increases the T-cell production of specific cytokines. ► Er-1 activates interleukin-2 receptor and extracellular signal-regulated kinases. ► The immuno-enhancing effect of Er-1 on Jurkat cells translates to an inhibition of human glioma cell growth.

  9. Ultrastructure of the rumen ciliate Dasytricha ruminantium.

    Science.gov (United States)

    Gordon Paul, R; Butler, R D; Williams, A G

    1989-04-14

    The ciliate Dasytricha ruminantium possesses cilia over the entire surface. Both the oral and somatic kineties are composed of monokinetids comprising a kinetosome, a tangential ribbon of 5 transverse microtubules, a weakly convergent bundle of 5 postciliary microtubules, a short kinetodesmal fibre, and a single microtubule homologous to T(2) of other litostomate ciliates [15]. The reversed orientation of the kineties within and around the vestibulum may be a consequence of the evolutionary migration of the vestibulum from the anterior to the posterior of the cell. The vestibulum leads to the cytostome and a cytopharynx of the rhabdos type [3]. Microtubules lining the exit canals of the posterior contractile vacuole and cytoproct are believed to originate from somatic kinetids. The ecto-endoplasmic boundary layer (eeb) is composed of two microfibrillar layers. A large extension of the eeb connects the vestibulum to the cell cortex but does not form a karyophore as seen in the closely related genus Isotricha [12].

  10. Analysis of ependymal ciliary beat pattern and beat frequency using high speed imaging: comparison with the photomultiplier and photodiode methods

    Directory of Open Access Journals (Sweden)

    O'Callaghan Chris

    2012-06-01

    Full Text Available Abstract Background The aim of this study was to compare beat frequency measurements of ependymal cilia made by digital high speed imaging to those obtained using the photomultiplier and modified photodiode techniques. Using high speed video analysis the relationship of the power and recover strokes was also determined. Methods Ciliated strips of ependyma attached to slices from the brain of Wistar rats were incubated at 30°C and observed using a ×50 water immersion lens. Ciliary beat frequency was measured using each of the three techniques: the high speed video, photodiode and photomultiplier. Readings were repeated after 30 minutes incubation at 37°C. Ependymal cilia were observed in slow motion and the precise movement of cilia during the recovery stroke relative to the path travelled during the power stroke was measured. Results The mean (95% confidence intervals beat frequencies determined by the high speed video, photomultiplier and photodiode at 30°C were 27.7 (26.6 to 28.8, 25.5 (24.4 to 26.6 and 20.8 (20.4 to 21.3 Hz, respectively. The mean (95% confidence intervals beat frequencies determined by the high speed video, photomultiplier and photodiode at 37°C were 36.4 (34 to 39.5, 38.4 (36.8 to 39.9 and 18.8 (16.9 to 20.5 Hz. The inter and intra observer reliability for measurement of ciliary beat frequency was 3.8% and 1%, respectively. Ependymal cilia were observed to move in a planar fashion during the power and recovery strokes with a maximum deviation to the right of the midline of 12.1(11.8 to 13.0° during the power stroke and 12.6(11.6 to 13.6° to the left of the midline during the recovery stroke. Conclusion The photodiode technique greatly underestimates ciliary beat frequency and should not be used to measure ependymal ciliary beat frequency at the temperatures studied. Ciliary beat frequency from the high speed video and photomultiplier techniques cannot be used interchangeably. Ependymal cilia had minimal deviation to

  11. La estria supranuclear de las células ciliadas en la rinitis alérgica Supranuclear stria of ciliated cells in allergic rhinitis

    Directory of Open Access Journals (Sweden)

    Ana Zerdiew

    2007-08-01

    Full Text Available Se estudiaron 80 pacientes adultos alérgicos, que cursaron con los siguientes cuadros clínicos: 16 casos de rinitis intermitente y 64 de rinitis persistente. Se realizó el recuento porcentual de la estría supranuclear de las células ciliadas, respecto de los leucocitos presentes en los extendidos obtenidos por toma endonasal. Con los datos obtenidos se clasificaron los extendidos en 4 grupos; Grupo A (N=23: predominio leucocitario eosinófilo con eosinofilia nasal >10%, Grupo B (N=15: abundantes leucocitos neutrófilos y eosinofilia nasal >10%, Grupo C (N=29: con escasos leucocitos, Grupo D (N=13: con abundantes leucocitos de predominio neutrófilo sin eosinofilia. Se observó que el incremento porcentual de estría supranuclear se correlacionó con eosinofilia nasal >10% y con las muestras que presentaron escasos leucocitos. Sin embargo se evidenció una marcada disminución del porcentaje de estría supranuclear en la leucocitosis neutrófila de etiología bacteriana.Nasal secretions were studied in 80 allergic adults patients: 16 with intermittent rhinitis and 64 with persistent rhinitis. The percentage of supranuclear stria of ciliated cells with regard to leucocytes was studied by nasal scraping. Four groups of patients were classified according to nasal leucocytic predominance: patients with eosinophilic predominance with eosinophils > 10% in Group A (N=23, patients with abundant neutrophils and eosinophils >10% in Group B (N=15, patients with scant leucocytes in Group C (N=29, patients with neutrophilic predominance without eosinophils in Group D (N=13. An increase of supranuclear stria percentage was correlated to eosinophils > 10% and also correlated to scant leucocytes. Nevertheless, a significant decrease of supranuclear stria percentage was observed in neutrophilic leukocytosis of bacterial etiology.

  12. Phylogeny of intestinal ciliates, including Charonina ventriculi, and comparison of microscopy and 18S rRNA gene pyrosequencing for rumen ciliate community structure analysis.

    Science.gov (United States)

    Kittelmann, Sandra; Devente, Savannah R; Kirk, Michelle R; Seedorf, Henning; Dehority, Burk A; Janssen, Peter H

    2015-04-01

    The development of high-throughput methods, such as the construction of 18S rRNA gene clone or pyrosequencing libraries, has allowed evaluation of ciliate community composition in hundreds of samples from the rumen and other intestinal habitats. However, several genera of mammalian intestinal ciliates have been described based only on morphological features and, to date, have not been identified using molecular methods. Here, we isolated single cells of one of the smallest but widely distributed intestinal ciliates, Charonina ventriculi, and sequenced its 18S rRNA gene. We verified the sequence in a full-cycle rRNA approach using fluorescence in situ hybridization and thereby assigned an 18S rRNA gene sequence to this species previously known only by its morphology. Based on its full-length 18S rRNA gene sequence, Charonina ventriculi was positioned within the phylogeny of intestinal ciliates in the subclass Trichostomatia. The taxonomic framework derived from this phylogeny was used for taxonomic assignment of trichostome ciliate 18S rRNA gene sequence data stemming from high-throughput amplicon pyrosequencing of rumen-derived DNA samples. The 18S rRNA gene-based ciliate community structure was compared to that obtained from microscopic counts using the same samples. Both methods allowed identification of dominant members of the ciliate communities and classification of the rumen ciliate community into one of the types first described by Eadie in 1962. Notably, each method is associated with advantages and disadvantages. Microscopy is a highly accurate method for evaluation of total numbers or relative abundances of different ciliate genera in a sample, while 18S rRNA gene pyrosequencing represents a valuable alternative for comparison of ciliate community structure in a large number of samples from different animals or treatment groups.

  13. Novel fusion genes and chimeric transcripts in ependymal tumors

    DEFF Research Database (Denmark)

    Olsen, Thale Kristin; Panagopoulos, Ioannis; Gorunova, Ludmila

    2016-01-01

    We have previously identified two ALK rearrangements in a subset of ependymal tumors using a combination of cytogenetic data and RNA sequencing. The aim of this study was to perform an unbiased search for fusion transcripts in our entire series of ependymal tumors. Fusion analysis was performed...... using the FusionCatcher algorithm on 12 RNA-sequenced ependymal tumors. Candidate transcripts were prioritized based on the software's filtering and manual visualization using the BLAST (Basic Local Alignment Search Tool) and BLAT (BLAST-like alignment tool) tools. Genomic and reverse transcriptase PCR...... with subsequent Sanger sequencing was used to validate the potential fusions. Fluorescent in situ hybridization (FISH) using locus-specific probes was also performed. A total of 841 candidate chimeric transcripts were identified in the 12 tumors, with an average of 49 unique candidate fusions per tumor. After...

  14. The ependymal region of the adult human spinal cord differs from other species and shows ependymoma-like features.

    Science.gov (United States)

    Garcia-Ovejero, Daniel; Arevalo-Martin, Angel; Paniagua-Torija, Beatriz; Florensa-Vila, José; Ferrer, Isidro; Grassner, Lukas; Molina-Holgado, Eduardo

    2015-06-01

    Several laboratories have described the existence of undifferentiated precursor cells that may act like stem cells in the ependyma of the rodent spinal cord. However, there are reports showing that this region is occluded and disassembled in humans after the second decade of life, although this has been largely ignored or interpreted as a post-mortem artefact. To gain insight into the patency, actual structure, and molecular properties of the adult human spinal cord ependymal region, we followed three approaches: (i) with MRI, we estimated the central canal patency in 59 control subjects, 99 patients with traumatic spinal cord injury, and 26 patients with non-traumatic spinal cord injuries. We observed that the central canal is absent from the vast majority of individuals beyond the age of 18 years, gender-independently, throughout the entire length of the spinal cord, both in healthy controls and after injury; (ii) with histology and immunohistochemistry, we describe morphological properties of the non-lesioned ependymal region, which showed the presence of perivascular pseudorosettes, a common feature of ependymoma; and (iii) with laser capture microdissection, followed by TaqMan® low density arrays, we studied the gene expression profile of the ependymal region and found that it is mainly enriched in genes compatible with a low grade or quiescent ependymoma (53 genes); this region is enriched only in 14 genes related to neurogenic niches. In summary, we demonstrate here that the central canal is mainly absent in the adult human spinal cord and is replaced by a structure morphologically and molecularly different from that described for rodents and other primates. The presented data suggest that the ependymal region is more likely to be reminiscent of a low-grade ependymoma. Therefore, a direct translation to adult human patients of an eventual therapeutic potential of this region based on animal models should be approached with caution.

  15. Ultrastructure of extrusomes in hypotrichous ciliate Pseudourostyla nova

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yao; WANG Zhengjun; ZHANG Jun; GU Fukang

    2011-01-01

    The ultrastructure of extrusomes of the hypotrichous ciliate Pseudourostyla nova was observed in scanning and transmission electron microscopy and enzyme-cytochemistry. The results show that the distribution, morphological characteristics, morphogenesis process, and extrusive process of the extrusomes in P. nova are different from the trichocysts in Paramecium, suggesting that the extrusomes of P. nova can respond to environmental stimuli, play an important role in the defense of this species, and cannot be regarded as "trichocysts". The results also suggest that the extrusomes might be originated from the Golgi apparatus and mature in the cytoplasm; after the extrusion of mature extrusomes, the residual substance might be reabsorbed and reused by the ciliate cell via food vacuoles, and take part in material recycling of the cell.

  16. Correlation between localization, age, and chromosomal imbalances in ependymal tumours as detected by CGH.

    NARCIS (Netherlands)

    Jeuken, J.W.M.; Sprenger, S.H.; Gilhuis, H.J.; Teepen, J.L.; Grotenhuis, J.A.; Wesseling, P.

    2002-01-01

    Ependymal tumours (ETs) are gliomas that arise from the ependymal lining of the cerebral ventricles and from the remnants of the central canal of the spinal cord. Both clinical and genetic studies suggest that distinct genetic subtypes of ETs exist, the subtypes being correlated with patient age and

  17. Ciliated protozoa of two antarctic lakes: analysis by quantitative protargol staining and examination of artificial substrates

    Science.gov (United States)

    Kepner, R. L. Jr; Wharton, R. A. Jr; Coats, D. W.; Wharton RA, J. r. (Principal Investigator)

    1999-01-01

    Planktonic and artificial substrate-associated ciliates have been identified in two perennially ice-covered antarctic lakes of the McMurdo Dry Valleys. Abundances estimated by quantitative protargol staining ranged from < 5 to 31690 cells l-1, levels that are comparable to those previously obtained using other methods. Nineteen ciliate taxa were identified from these lakes, with the most frequently encountered genera being Plagiocampa, Askenasia, Monodinium, Sphaerophrya and Vorticella. The taxonomic findings compare favorably with those of previous investigators; however four previously unreported genera were observed in both Lakes Fryxell and Hoare. The variability in the depth distributions of ciliates in Lake Fryxell is explained in terms of lake physicochemical properties and ciliate prey distributions, while factors related to temporal succession in the Lake Hoare assemblage remain unexplained. Local marine or temperate zone freshwater habitats are a more likely source than the surrounding dry valleys soils for present ciliate colonists in these lakes. Although the taxonomic uncertainties require further examination, our results suggest that ciliate populations in these antarctic lakes undergo significant fluctuations and are more diverse than was previously recognized.

  18. The fenestrin antigen in submembrane skeleton of the ciliate Tetrahymena thermophila is proposed as a marker of cell polarity during cell division and in oral replacement.

    Science.gov (United States)

    Kaczanowska, Janina; Joachimiak, Ewa; Kiersnowska, Mauryla; Krzywicka, Anna; Golinska, Krystyna; Kaczanowski, Andrzej

    2003-07-01

    Tetrahymena thermophila cells have two types of polarized morphogenesis: divisional morphogenesis and oral reorganization (OR). The aim of this research is the analysis of cortical patterns of immunostaining during cell division and in OR using previously characterized antibodies against fenestrin and epiplasm B proteins. During cell division, the anarchic field of basal body proliferation of the new developing oral apparatus (AF) showed concomitant strong binding of the fenestrin antigen and withdrawal of a signal of the epiplasm B antigen. At a specific stage, the fenestrin antigen also appeared as a character of the anterior cortex pole, with a co-localized decrease in the detected epiplasm B antigen. The fenestrin antigen also showed a polarity of duplicating basal bodies in ciliary rows. Indirect immunofluorescence and immunogold labeling experiments were performed in the absence and presence of an inhibitor of activity of serine/threonine kinases, 6-dimethylaminopurine (6-DMAP) as an inducer of the oral replacement process. In the presence of 6-DMAP, one class of cells started OR, and some others were trapped and affected in cell division. Both types of cells showed an instability of oral structures and formed enlarged primordial oral fields. These anarchic fields (AFs) bind the fenestrin antigen, with disappearance of epiplasmic antigen staining. Only one protein (about 64 kDa) is detected in western blots by the anti-fenestrin antibody and it accumulated in 6-DMAP-treated cells that are involved in uncompleted morphogenetic activity. At a defined stage of oral development, both during cell division and in OR, the fenestrin antigen served as a marker of polarity of the cell of the anterior pole character.

  19. Ciliate communities consistently associated with coral diseases

    Science.gov (United States)

    Sweet, M. J.; Séré, M. G.

    2016-07-01

    Incidences of coral disease are increasing. Most studies which focus on diseases in these organisms routinely assess variations in bacterial associates. However, other microorganism groups such as viruses, fungi and protozoa are only recently starting to receive attention. This study aimed at assessing the diversity of ciliates associated with coral diseases over a wide geographical range. Here we show that a wide variety of ciliates are associated with all nine coral diseases assessed. Many of these ciliates such as Trochilia petrani and Glauconema trihymene feed on the bacteria which are likely colonizing the bare skeleton exposed by the advancing disease lesion or the necrotic tissue itself. Others such as Pseudokeronopsis and Licnophora macfarlandi are common predators of other protozoans and will be attracted by the increase in other ciliate species to the lesion interface. However, a few ciliate species (namely Varistrombidium kielum, Philaster lucinda, Philaster guamense, a Euplotes sp., a Trachelotractus sp. and a Condylostoma sp.) appear to harbor symbiotic algae, potentially from the coral themselves, a result which may indicate that they play some role in the disease pathology at the very least. Although, from this study alone we are not able to discern what roles any of these ciliates play in disease causation, the consistent presence of such communities with disease lesion interfaces warrants further investigation.

  20. In vitro differentiation of chick spinal cord neurons in the presence of Reissner's fibre, an ependymal brain secretion.

    Science.gov (United States)

    Monnerie, H; Dastugue, B; Meiniel, A

    1997-09-20

    The subcommissural organ (SCO), which belongs to the circumventricular organs, is a specialized ependymal structure of the brain that secretes glycoproteins into the cerebrospinal fluid (CSF) which condense to form a thread-like structure, the Reissner's fibre (RF). Regarding the presence of this ependymal brain secretion all along the central canal of the developing spinal cord, we analysed a putative developmental activity of RF on neuronal spinal cord cells. The effects of RF proper and soluble RF-material were examined in primary cultures of dissociated spinal cord cells from day 6 chicken embryos. In serum-containing mixed glial/neuronal cell cultures, both RF and soluble RF-material promoted neuronal survival. This effect was blocked by addition of specific antibodies raised against bovine RF into the culture medium. In serum-free neuron-enriched cultures, no neuronal survival activity was observed; however, under these conditions RF proper induced neuronal aggregation and neuritic outgrowth of spinal cord cells. Interestingly, neurites extending from the aggregates appeared mainly unfasciculated. Our results suggest a direct modulation of cell-cell interactions by SCO/RF glycoproteins and an indirect survival effect on neurons. These data strengthen the hypothesis of the involvement of SCO/RF complex in the development of the central nervous system (CNS) and are discussed regarding molecular features of SCO-spondin, a novel glycoprotein recently identified in this complex.

  1. Bioassay of environmental nickel dusts in a particle feeding ciliate

    Energy Technology Data Exchange (ETDEWEB)

    Smith-Sonneborn, J.; Leibovitz, B.; Donathan, R.; Fisher, G.L.

    1986-01-01

    The ciliated protozoan Paramecium was used to quantitate cytotoxic and genotoxic effects of nickel particles. The biological response of these eukaryotic cells to pure nickel powder and iron-nickel powder was assayed and compared to the effect of the inorganic carcinogen nickel subsulfide. Cytotoxicity was determined by the percent survival of treated cells. Genotoxicity was indicated by significant increases in the fraction of nonviable offspring (presumed index of lethal mutations) found after self-fertilization (autogamy) in parents from the nickel-treated versus neutral control groups. The cells were exposed to the dusts and the biological effects determined. Only the nickel subsulfide consistently showed a significant increase in offspring lethality.

  2. The Cutaneous Ciliated Cyst in Young Male: The Possibility of Ciliated Cutaneous Eccrine Cyst

    Science.gov (United States)

    Kim, Youngjoon; Kim, Hyunjung

    2015-01-01

    Cutaneous ciliated cyst was described as a painless cyst occurring on the lower limbs of women between the ages of 15 and 30 years. The cysts are typically lined by ciliated cuboidal to columnar epithelium with pseudostratified areas and focal squamous metaplasia is occasionally present. Immunohistochemical studies have demonstrated that the cysts are PR and ER positive, similar to the epithelia of the fallopian tubes. However, outliers of cutaneous ciliated cysts, including those in male patients and in unexpected locations such as the scalp, finger, and scapular area, have been reported. Thus, some hypotheses have been proposed including the Mullerian heterotopias, ciliated metaplasia of eccrine sweat glands, and embryonic remnants of the cloacal membrane. We report a rare case of cutaneous ciliated cyst on the left shoulder of a 7-year-old boy and this is the eighth case of cutaneous ciliated cyst in male patients. Moreover, through reviewing the articles, we try to propose the classification of the cutaneous ciliated cysts into the cutaneous Mullerian cysts and the ciliated cutaneous eccrine cysts. PMID:26491452

  3. The Cutaneous Ciliated Cyst in Young Male: The Possibility of Ciliated Cutaneous Eccrine Cyst

    Directory of Open Access Journals (Sweden)

    Youngjoon Kim

    2015-01-01

    Full Text Available Cutaneous ciliated cyst was described as a painless cyst occurring on the lower limbs of women between the ages of 15 and 30 years. The cysts are typically lined by ciliated cuboidal to columnar epithelium with pseudostratified areas and focal squamous metaplasia is occasionally present. Immunohistochemical studies have demonstrated that the cysts are PR and ER positive, similar to the epithelia of the fallopian tubes. However, outliers of cutaneous ciliated cysts, including those in male patients and in unexpected locations such as the scalp, finger, and scapular area, have been reported. Thus, some hypotheses have been proposed including the Mullerian heterotopias, ciliated metaplasia of eccrine sweat glands, and embryonic remnants of the cloacal membrane. We report a rare case of cutaneous ciliated cyst on the left shoulder of a 7-year-old boy and this is the eighth case of cutaneous ciliated cyst in male patients. Moreover, through reviewing the articles, we try to propose the classification of the cutaneous ciliated cysts into the cutaneous Mullerian cysts and the ciliated cutaneous eccrine cysts.

  4. 脊髓室管膜细胞再生修复的潜力和其他相关细胞靶向治疗策略%Potential of spinal cord ependymal cells reproduction and other related cell targeted therapeutic strategies

    Institute of Scientific and Technical Information of China (English)

    魏子淳; 王宇; 徐熙萌; 吴畏; 饶晨旭; 谭会兵

    2015-01-01

    In the central nervous system, the ependymal cells (EC) in central canal of the spinal cord remain the persistence of a pool of stem and progenitor cells. Terminology of the EC niche as an entity of action not only showed neural stem cell potential but functioned beyond physiological and anatomical manners. The spinal cord EC generated astrocytes, oligodendrocytes and neurons in vitro and in vivo in injured spinal cord. However, it was still a challenge that the long term survival of spinal cord injury (SCI) treated by the stem cells transplanted in a fibrin matrix with a growth factor cocktail. Recently, the non-neuronal cells were directly converted into functional neurons in vivo, which opened up a new cellular therapy. With ultimate design of the therapeutics, we still need further to investigate how to manipulation of the proliferation and differentiation of EC or reprogramming of non-neuronal components into neuronal compartments,and constitute and functionally sustain the transplantation of stem cells and cellular modification in vivo until functional recovery in following SCI. We should figure out a new concept other than the traditional cell and tissue, stem cell niche, which could be non-traditionally mimicked in our human bodies to treatment of SCI under biomedical micro-ecology.%中枢神经系统中,脊髓中央管室管膜细胞(EC)具有一定的再生修复能力,是特化的不仅限于功能形态学的活性单位,后者作为特定的术语,它的意义超出生理学和解剖学定义。在损伤条件下,EC即可增殖分化为星形胶质细胞、少突胶质细胞和神经元。目前,复合生长因子和纤维蛋白支架的干细胞实验性治疗研究还存在长期疗效的争议。在中枢神经系统原位,使非神经元直接转化为功能性神经元研究方法,为脊髓损伤和疾病提供了新的治疗策略。在设计细胞治疗,如何控制EC增殖和分化或其他非神经元转化为神经元,继

  5. Photoperiodic regulation of cellular retinol binding protein, CRBP1 [corrected] and nestin in tanycytes of the third ventricle ependymal layer of the Siberian hamster.

    Science.gov (United States)

    Barrett, Perry; Ivanova, Elena; Graham, E Scott; Ross, Alexander W; Wilson, Dana; Plé, Helene; Mercer, Julian G; Ebling, Francis J; Schuhler, Sandrine; Dupré, Sandrine M; Loudon, Andrew; Morgan, Peter J

    2006-12-01

    Tanycytes in the ependymal layer of the third ventricle act both as a barrier and a communication gateway between the cerebrospinal fluid, brain and portal blood supply to the pituitary gland. However, the range, importance and mechanisms involved in the function of tanycytes remain to be explored. In this study, we have utilized a photoperiodic animal to examine the expression of three unrelated gene sequences in relation to photoperiod-induced changes in seasonal physiology and behaviour. We demonstrate that cellular retinol binding protein [corrected] (CRBP1), a retinoic acid transport protein, GPR50, an orphan G-protein-coupled receptor and nestin, an intermediate filament protein, are down-regulated in short-day photoperiods. The distribution of the three sequences is very similar, with expression located in cells with tanycyte morphology in the region of the ependymal layer where tanycytes are located. Furthermore, CRBP1 expression in the ependymal layer is shown to be independent of a circadian clock and altered testosterone levels associated with testicular regression in short photo-period. Pinealectomy of Siberian hamsters demonstrates CRBP1 expression is likely to be dependent on melatonin output from the pineal gland. This provides evidence that tanycytes are seasonally responsive cells and are likely to be an important part of the mechanism to facilitate seasonal physiology and behaviour in the Siberian hamster.

  6. Rumen ciliate protozoa of domestic sheep (Ovis aries) and goat (Capra aegagrus hircus) in Kyrgyzstan.

    Science.gov (United States)

    Gürelli, Gözde; Canbulat, Savaş; Aldayarov, Nurbek; Dehority, Burk A

    2016-03-01

    Species composition and concentration of rumen ciliate protozoa were investigated in the rumen contents of 14 domestic sheep and 1 goat living in Bishkek, Kyrgyzstan. This is the first report on rumen ciliates from ruminants living in Kyrgyzstan. In sheep 12 genera, 28 species and 12 morphotypes were detected, whereas in goat 8 genera, 12 species and 4 morphotypes were detected. The density of ciliates in sheep was (28.1 ± 20.0) × 10(4) cells mL(-1) and in goat was 37.0 × 10(4) cells mL(-1). Dasytricha ruminantium, Isotricha prostoma, Entodinium simulans and Ophryoscolex caudatus were major species (100%) in sheep, and for the first time, Diplodinium rangiferi was detected in a domestic goat.

  7. Are freshwater mixotrophic ciliates less sensitive to solar ultraviolet radiation than heterotrophic ones?

    Science.gov (United States)

    Sonntag, Bettina; Summerer, Monika; Sommaruga, Ruben

    2011-01-01

    We tested whether mixotrophic ciliates are more resistant to solar ultraviolet radiation (UVR) than heterotrophic ones because symbiotic algae can provide self-shading by cell matter absorption and eventually by direct UV screening from mycosporine-like amino acids (MAAs). Sensitivity of a natural assemblage to solar radiation was tested in experiments in the original lake and in a more UV transparent alpine lake after transplantation of the ciliates. In both lakes, the assemblage was exposed either to full sunlight, to photosynthetically active radiation only, or kept in the dark. In each lake, exposure was for 5 h at the surface and at the depth corresponding to the 10% attenuation depth at 320 nm. Overall, when the assemblage was exposed to surface UVR, only one out of four dominant mixotrophic ciliates, Vorticella chlorellata, was more resistant than heterotrophic species. The higher UV resistance in V. chlorellata was related to the presence of MAAs and the high percentage of ciliate volume occupied by algal symbionts. Our results indicate that effects of UVR were species-specific and depended on efficient screening of these wavelengths, but also on the depth preference of the ciliates and thus, on their previous exposure history to UVR.

  8. Are Freshwater Mixotrophic Ciliates Less Sensitive to Solar Ultraviolet Radiation than Heterotrophic Ones?1

    Science.gov (United States)

    SONNTAG, BETTINA; SUMMERER, MONIKA; SOMMARUGA, RUBEN

    2011-01-01

    We tested whether mixotrophic ciliates are more resistant to solar ultraviolet radiation (UVR) than heterotrophic ones because symbiotic algae can provide self-shading by cell matter absorption and eventually by direct UV screening from mycosporine-like amino acids (MAAs). Sensitivity of a natural assemblage to solar radiation was tested in experiments in the original lake and in a more UV transparent alpine lake after transplantation of the ciliates. In both lakes, the assemblage was exposed either to full sunlight, to photosynthetically active radiation only, or kept in the dark. In each lake, exposure was for 5 h at the surface and at the depth corresponding to the 10% attenuation depth at 320 nm. Overall, when the assemblage was exposed to surface UVR, only one out of four dominant mixotrophic ciliates, Vorticella chlorellata, was more resistant than heterotrophic species. The higher UV resistance in V. chlorellata was related to the presence of MAAs and the high percentage of ciliate volume occupied by algal symbionts. Our results indicate that effects of UVR were species-specific and depended on efficient screening of these wavelengths, but also on the depth preference of the ciliates and thus, on their previous exposure history to UVR. PMID:21414057

  9. Revisiting fifty years of research on pheromone signaling in ciliates.

    Science.gov (United States)

    Luporini, Pierangelo; Pedrini, Bill; Alimenti, Claudio; Vallesi, Adriana

    2016-08-01

    Among protists, pheromones have been identified in a great variety of algal species for their activity in driving gamete-gamete interactions for fertilization. Analogously in ciliates, pheromones have been identified for their activity in inducing the sexual phenomenon of conjugation. Although this identification was pioneered by Kimball more than fifty years ago, an effective isolation and chemical characterization of ciliate pheromones has remained confined to species of Blepharisma, Dileptus and Euplotes. In Euplotes species, in which the molecular structures have been determined, pheromones form species-specific families of structurally homologous helical, cysteine-rich, highly-stable proteins. Being structurally homologous, they can bind cells in competition with one another, raising interesting functional analogies with the families of growth factors and cytokines that regulate cell differentiation and development in higher organisms. In addition to inducing conjugation by binding cells in heterologous fashion, Euplotes pheromones act also as autocrine growth factors by binding to, and promoting the vegetative reproduction of the same cells from which they originate. This autocrine activity is most likely primary, providing a concrete example of how the original function of a molecule can be obscured during evolution by the acquisition of a new one.

  10. Imaging features of ciliated hepatic foregut cyst

    Institute of Scientific and Technical Information of China (English)

    Song-Hua Fang; Dan-Jun Dong; Shi-Zheng Zhang

    2005-01-01

    Ciliated hepatic foregut cyst (CHFC) is a very rare cystic lesion of the liver that is histologically similar to bronchogenic cyst. We report one case of CHFC that was hard to distinguish from solid-cystic neoplasm in imaging features. Magnetic resonance imaging was helpful in differentiating these cysts from other lesions.

  11. Dealing with the presence of the ciliate Euplotes sp. in cultures of the copepod Acartia tonsa

    DEFF Research Database (Denmark)

    Drillet, Guillaume; Dutz, Jörg

    2014-01-01

    Ciliates in live feed cultures can be a pest that lower production yields. This could dramatically affect the management and success of copepod cultures. In this study, we investigated the effect of the ciliate Euplotes sp. on egg production, specific egg production and egg hatching success...... of Acartia tonsa fed with Rhodomonas salina. We found that at a concentration of 2 cells ml-1, Euplotes sp. had no effect on the production and hatching success of eggs but increased/decreased the mortality/quality of non-subitaneous eggs. Euplotes sp. had a good fatty acid profile containing high proportion...

  12. Cycloheptaamylose-dansyl chloride complex as a fluorescent label of surface membranes in living ciliates.

    Science.gov (United States)

    Wyroba, E; Bottiroli, G; Giordano, P

    1981-12-01

    Labelling of surface membrane of living ciliates: Paramecium aurelia and Tetrahymena pyriformis with fluorescent compound--cycloheptaamylose-dansyl chloride complex (CDC) has been achieved. Fluorescence micrographs of the dried samples showed specific localization of CDC on the cell membrane without any intracellular penetration. On the contrary the ciliates which have been dead during labelling revealed a non-specific fluorescence of their whole bodies. Microspectrofluorimetric analysis of labelled Paramecium cells was performed with Leitz microspectrograph. Spectrum of fluorescence emission measured over the cell membrane level had maximum at 450 nm. Strikingly, the emission maximum of the cells dead at the moment of labelling was shifted 10 nm to a longer wavelength. The rate of photofading measured in this case was almost 3-fold higher than for the ciliates labelled as living ones. Fluorescence excitation spectra did not show any difference in the peak position. Thus CDC staining appears to be an useful method of supravital labelling of cell surface enabling also to distinguish--on the basis of spectral characteristics--the ciliates being alive from those dead at the moment of fluorochrome binding.

  13. Act together – implications of symbioses in aquatic ciliates

    Directory of Open Access Journals (Sweden)

    Claudia eDziallas

    2012-08-01

    Full Text Available Mutual interactions in form of symbioses can increase the fitness of organisms and provide them with the capacity to occupy new ecological niches. The formation of obligate symbioses allows for rapid evolution of new life forms including multitrophic consortia. Microbes are important components of many known endosymbioses and their short generation times and strong potential for genetic exchange may be important drivers of speciation. Hosts provide endo- and ectosymbionts with stable, nutrient-rich environments and protection from environmental stresses. This is of particular importance in aquatic ecosystems, which are often highly variable, harsh and nutrient-deficient habitats. Thus it is not surprising that symbioses are widespread in both marine and freshwater environments. Symbioses in aquatic ciliates are good model systems for exploring symbiont-host interactions. Many ciliate species are globally distributed and have been intensively studied in the context of plastid evolution. Their relatively large cell size offers an ideal habitat for numerous microorganisms with different functional traits including commensalism and parasitism. Phagocytosis facilitates the formation of symbiotic relationships, particularly since some ingested microorganisms can escape the digestion. For example, photoautotrophic algae and methanogens represent endosymbionts that greatly extend the biogeochemical functions of their hosts. Consequently, symbiotic relationships between protists and prokaryotes are widespread and often result in new ecological functions of symbiotic communities. This enables ciliates to thrive under a wide range of environmental conditions including ultraoligotrophic or anoxic habitats. We summarize the current understanding of this exciting research topic to identify the many areas in which knowledge is lacking and to stimulate future research by providing an overview on new methodologies and by formulating a number of emerging

  14. The bacterivory of interstitial ciliates in association with bacterial biomass and production in the hyporheic zone of a lowland stream.

    Science.gov (United States)

    Königs, Sascha; Cleven, Ernst-Josef

    2007-07-01

    Rates of bacteria ingestion by interstitial ciliates were estimated and compared to bacterial biomass and production. Investigation was carried out in the hyporheic zone of a lowland stream. FISH was applied to quantitatively determine bacteria within the ciliate's food vacuoles. To estimate bacteria ingestion rates using FISH, we had to strike a new path. When numbers of bacteria in the food vacuoles remains constant with time (bacterial digestion and ingestion are at equilibrium), ingestion rate can be estimated based on the digestion time and the average number of bacteria per cell. Ciliate community was predominantly composed of bacterivorous ciliates. FISH-signals deriving from ingested bacteria were detected in Cinetochilum margaritaceum, 'other small scuticociliates', Pleuronema spp., and Vorticella spp. Ingestion rates for these taxa were 78, 150, 86, and 38 bacteria ind(-1) h(-1), respectively. The grazing impacts on bacterial biomass and carbon production were calculated based on these ingestion rates. Ciliate grazing caused a decrease in bacterial biomass of 0.024% day(-1) and in bacterial carbon production of 1.60%. These findings suggest that interstitial ciliate grazing impact on bacteria biomass and production was too low to represent an important link in the carbon flow of the hyporheic zone under study.

  15. Ciliates and their picophytoplankton-feeding activity in a high-altitude warm-monomictic saline lake.

    Science.gov (United States)

    Pestová, Dana; Macek, Miroslav; Elena Martínez Pérez, María

    2008-02-01

    The impact of feeding on autotrophic picoplankton (APP) on the ciliate composition of the assemblage was surveyed monthly along a depth gradient in the maar crater, athalassohaline, warm monomictic Lake Alchichica (Puebla, Mexico) from June 2003 to December 2005. Numbers of APP were evaluated from their autofluorescence. DAPI staining and the Fluorescently Labeled Bacteria technique were employed to count ciliates and estimate their feeding rates. A total of 38 taxa of ciliates have been identified using Quantitative Protargol Staining. Peritrichs followed by minute spirotrichs (particularly Halteria grandinella) often numerically dominated the ciliate assemblage and emerged as the most efficient APP feeders. A maximum of 54 ciliate cells ml(-1) was observed in the surface layer at the end of the mixing period, during the development of diatoms (Cyclotella alchichicana), the cyanobacterial bloom (Nodularia sp.) and its decay. Vorticellids (Pelagovorticella natans, Vorticella sp.) had the highest APP uptake (median 130 APP cil(-1) h(-1)). Mixotrophic Euplotes cf. daidaleos were important APP grazers near the oxycline. Scuticociliates (Cyclidium glaucoma, Uronema nigricans and an anaerobic cf. Isocyclidium globossum), were numerically dominant within the hypolimnetic assemblages and did not ingest APP. Generally, APP were not an important food source for the majority of the ciliate assemblage, being positively selected by a few species during the APP decay in aerobic and microaerobic conditions.

  16. The adult macaque spinal cord central canal zone contains proliferative cells and closely resembles the human.

    Science.gov (United States)

    Alfaro-Cervello, Clara; Cebrian-Silla, Arantxa; Soriano-Navarro, Mario; Garcia-Tarraga, Patricia; Matías-Guiu, Jorge; Gomez-Pinedo, Ulises; Molina Aguilar, Pilar; Alvarez-Buylla, Arturo; Luquin, Maria-Rosario; Garcia-Verdugo, Jose Manuel

    2014-06-01

    The persistence of proliferative cells, which could correspond to progenitor populations or potential cells of origin for tumors, has been extensively studied in the adult mammalian forebrain, including human and nonhuman primates. Proliferating cells have been found along the entire ventricular system, including around the central canal, of rodents, but little is known about the primate spinal cord. Here we describe the central canal cellular composition of the Old World primate Macaca fascicularis via scanning and transmission electron microscopy and immunohistochemistry and identify central canal proliferating cells with Ki67 and newly generated cells with bromodeoxyuridine incorporation 3 months after the injection. The central canal is composed of uniciliated, biciliated, and multiciliated ependymal cells, astrocytes, and neurons. Multiciliated ependymal cells show morphological characteristics similar to multiciliated ependymal cells from the lateral ventricles, and uniciliated and biciliated ependymal cells display cilia with large, star-shaped basal bodies, similar to the Ecc cells described for the rodent central canal. Here we show that ependymal cells with one or two cilia, but not multiciliated ependymal cells, proliferate and give rise to new ependymal cells that presumably remain in the macaque central canal. We found that the infant and adult human spinal cord contains ependymal cell types that resemble those present in the macaque. Interestingly, a wide hypocellular layer formed by bundles of intermediate filaments surrounded the central canal both in the monkey and in the human, being more prominent in the stenosed adult human central canal.

  17. Hypothalamic ventricular ependymal thyroid hormone deiodinases are an important element of circannual timing in the Siberian hamster (Phodopus sungorus.

    Directory of Open Access Journals (Sweden)

    Annika Herwig

    Full Text Available Exposure to short days (SD induces profound changes in the physiology and behaviour of Siberian hamsters, including gonadal regression and up to 30% loss in body weight. In a continuous SD environment after approximately 20 weeks, Siberian hamsters spontaneously revert to a long day (LD phenotype, a phenomenon referred to as the photorefractory response. Previously we have identified a number of genes that are regulated by short photoperiod in the neuropil and ventricular ependymal (VE cells of the hypothalamus, although their importance and contribution to photoperiod induced physiology is unclear. In this refractory model we hypothesised that the return to LD physiology involves reversal of SD expression levels of key hypothalamic genes to their LD values and thereby implicate genes required for LD physiology. Male Siberian hamsters were kept in either LD or SD for up to 39 weeks during which time SD hamster body weight decreased before increasing, after more than 20 weeks, back to LD values. Brain tissue was collected between 14 and 39 weeks for in situ hybridization to determine hypothalamic gene expression. In VE cells lining the third ventricle, expression of nestin, vimentin, Crbp1 and Gpr50 were down-regulated at 18 weeks in SD photoperiod, but expression was not restored to the LD level in photorefractory hamsters. Dio2, Mct8 and Tsh-r expression were altered by SD photoperiod and were fully restored, or even exceeded values found in LD hamsters in the refractory state. In hypothalamic nuclei, expression of Srif and Mc3r mRNAs was altered at 18 weeks in SD, but were similar to LD expression values in photorefractory hamsters. We conclude that in refractory hamsters not all VE cell functions are required to establish LD physiology. However, thyroid hormone signalling from ependymal cells and reversal of neuronal gene expression appear to be essential for the SD refractory response.

  18. Hypothalamic ventricular ependymal thyroid hormone deiodinases are an important element of circannual timing in the Siberian hamster (Phodopus sungorus).

    Science.gov (United States)

    Herwig, Annika; de Vries, Emmely M; Bolborea, Matei; Wilson, Dana; Mercer, Julian G; Ebling, Francis J P; Morgan, Peter J; Barrett, Perry

    2013-01-01

    Exposure to short days (SD) induces profound changes in the physiology and behaviour of Siberian hamsters, including gonadal regression and up to 30% loss in body weight. In a continuous SD environment after approximately 20 weeks, Siberian hamsters spontaneously revert to a long day (LD) phenotype, a phenomenon referred to as the photorefractory response. Previously we have identified a number of genes that are regulated by short photoperiod in the neuropil and ventricular ependymal (VE) cells of the hypothalamus, although their importance and contribution to photoperiod induced physiology is unclear. In this refractory model we hypothesised that the return to LD physiology involves reversal of SD expression levels of key hypothalamic genes to their LD values and thereby implicate genes required for LD physiology. Male Siberian hamsters were kept in either LD or SD for up to 39 weeks during which time SD hamster body weight decreased before increasing, after more than 20 weeks, back to LD values. Brain tissue was collected between 14 and 39 weeks for in situ hybridization to determine hypothalamic gene expression. In VE cells lining the third ventricle, expression of nestin, vimentin, Crbp1 and Gpr50 were down-regulated at 18 weeks in SD photoperiod, but expression was not restored to the LD level in photorefractory hamsters. Dio2, Mct8 and Tsh-r expression were altered by SD photoperiod and were fully restored, or even exceeded values found in LD hamsters in the refractory state. In hypothalamic nuclei, expression of Srif and Mc3r mRNAs was altered at 18 weeks in SD, but were similar to LD expression values in photorefractory hamsters. We conclude that in refractory hamsters not all VE cell functions are required to establish LD physiology. However, thyroid hormone signalling from ependymal cells and reversal of neuronal gene expression appear to be essential for the SD refractory response.

  19. Ciliates and the rare biosphere: a review.

    Science.gov (United States)

    Dunthorn, Micah; Stoeck, Thorsten; Clamp, John; Warren, Alan; Mahé, Frédéric

    2014-01-01

    Here we provide a brief review of the rare biosphere from the perspective of ciliates and other microbial eukaryotes. We trace research on rarity from its lack of much in-depth focus in morphological and Sanger sequencing projects, to its central importance in analyses using high throughput sequencing strategies. The problem that the rare biosphere is potentially comprised of mostly errors is then discussed in the light of asking community-comparative, novel-diversity, and ecosystem-functioning questions.

  20. First report of folliculinid ciliates affecting Caribbean scleractinian corals

    Science.gov (United States)

    Cróquer, A.; Bastidas, C.; Lipscomp, D.; Rodríguez-Martínez, R. E.; Jordan-Dahlgren, E.; Guzman, H. M.

    2006-05-01

    This is the first report of a ciliate of the genus Halofolliculina infecting hard coral species of six families (Acroporidae, Agaricidae, Astrocoeniidae, Faviidae, Meandrinidae and Poritidae) and milleporids in the Caribbean. Surveys conducted during 2004 2005 in Venezuela, Panama and México confirmed that this ciliate affects up to 25 scleractinian species. The prevalence of this ciliate at the coral community level was variable across sites, being most commonly found at Los Roques, Venezuela, and at Bocas del Toro, Panama (prevalence 0.2 2.5%), but rarely observed in the Mexican Caribbean. Ciliates were more prevalent within populations of acroporids ( Acropora palmata, Acropora cervicornis and Acropora prolifera) in Los Roques. Recent observations also corroborate the presence of these ciliates in Curacao and Puerto Rico. Our observations indicate that ciliates affecting corals have a wider distribution than previously thought, and are no longer exclusively found in the Indo-Pacific and Red Sea.

  1. Evaluation of double formalin--Lugol's fixation in assessing number and biomass of ciliates: an example of estimations at mesoscale in NE Atlantic.

    Science.gov (United States)

    Karayanni, Hera; Christaki, Urania; Van Wambeke, France; Dalby, Andrew P

    2004-03-01

    Ciliated protozoa are potential grazers of primary and bacterial production and act as intermediaries between picoplankton and copepods and other large suspension feeders. Accurate determination of ciliate abundance and feeding mode is crucial in oceanic carbon budget estimations. However, the impact of different fixatives on the abundance and cell volume of ciliates has been investigated in only a few studies using either laboratory cultures or natural populations. Lugol's solution and formalin are the most commonly used fixatives for the preservation of ciliates samples. In the present study, the aim was to compare 0.4% Lugol's solution and 2% borated-formalin fixation and evaluate the need of counting duplicate samples each using a different fixative. For this, a large number of samples (n = 110) from the NE Atlantic was analyzed in the frame of POMME program (Multidisciplinary Mesoscale Ocean Program). We established a statistically significant relationship (p Lugol's and formalin fixed samples for both abundance (r2 = 0.50) and biomass (r2 = 0.76) of aloricate ciliates which showed that counts were higher in Lugol's solution by a factor of 2 and a non-taxon specific cell-loss in formalin. However, loricate ciliate abundance in our samples which were represented primarily by Tintinnus spp. did not show any difference between the two treatments. Abundance and biomass of mixotrophic ciliates (chloroplast-bearing cells) were for various reasons underestimated in both treatments. Our results show that unique fixation by formalin may severely underestimate ciliates abundance and biomass although their population may not alter. For this reason, Lugol's solution is best for the estimation of their abundance and biomass. However, for counts of mixotrophs and the evaluation of the ecological role of ciliates in carbon flux, double fixation is essential. Compromises regarding the fixatives have lead to severe underestimations of mixotrophs in studies conducted by now.

  2. Biodiversity patterns of soil ciliates along salinity gradients.

    Science.gov (United States)

    Zhao, Feng; Xu, Kuidong

    2016-04-01

    We evaluated ciliate diversity in saline soils with a salinity range from 6.5 to 65 psu by the morphological method of the Ludox-quantitative protargol stain (QPS) and the molecular techniques of ciliate-specific clone library and denaturing gradient gel electrophoresis. No active ciliates could be detected with the Ludox-QPS method, while high molecular diversity of ciliates was found. The highest ciliate molecular diversity was obtained from the soil at salinity of 8.9 psu, moderate diversity was found at salinity of 6.5 psu, and the diversity sharply decreased at salinity of 50.5 psu. By contrast, the number of ciliate classes clearly decreased with increasing soil salinity: six, five, four and two classes from sites with salinity of 6.5 psu, 8.9 psu, 29.5 psu and 50.5 psu, respectively. Ciliate diversity pattern is different from that of bacteria, whose diversity is also high in extremely saline environments. Meanwhile, the composition of ciliate community was significantly different along salinity gradient. Colpodea and Oligohymenophorea were diverse in soils at salinity less than 29.5 psu, while absent in soils with salinity above 50.5 psu. BIOENV analysis indicated soil salinity and water content were the main factors regulating the distribution of ciliates in saline soils.

  3. Symptomatic ependymal cysts of the perimesencephalic and cerebello-pontine angle cisterns.

    Science.gov (United States)

    Sharma, R R; Pawar, S J; Kharangate, P P; Delmendo, A

    2000-11-01

    Primary intracranial ependymal cysts are extremely rare. These are congenital, benign ependyma lined, commonly intraparenchymal and uncommonly extraparenchymal cysts in leptomeningeal location of variable size seen in the adult life. The authors report two cases of symptomatic ependymal cysts: one in the perimesencephalic cistern in a 10-month-old infant presenting with delayed mile stones and another in the cerebello-pontine cistern in a morbidly obese 35-year-old woman with known benign intracranial hypertension now presenting with hemifacial spasm. Neurosurgical intervention was curative in both cases. Interesting clinical, radiological and histological features are presented and discussed.

  4. Expansion of the lateral ventricles and ependymal deficits underlie the hydrocephalus evident in mice lacking the transcription factor NFIX.

    Science.gov (United States)

    Vidovic, Diana; Harris, Lachlan; Harvey, Tracey J; Evelyn Heng, Yee Hsieh; Smith, Aaron G; Osinski, Jason; Hughes, James; Thomas, Paul; Gronostajski, Richard M; Bailey, Timothy L; Piper, Michael

    2015-08-01

    Nuclear factor one X (NFIX) has been shown to play a pivotal role during the development of many regions of the brain, including the neocortex, the hippocampus and the cerebellum. Mechanistically, NFIX has been shown to promote neural stem cell differentiation through the activation of astrocyte-specific genes and via the repression of genes central to progenitor cell self-renewal. Interestingly, mice lacking Nfix also exhibit other phenotypes with respect to development of the central nervous system, and whose underlying causes have yet to be determined. Here we examine one of the phenotypes displayed by Nfix(-/-) mice, namely hydrocephalus. Through the examination of embryonic and postnatal Nfix(-/-) mice we reveal that hydrocephalus is first seen at around postnatal day (P) 10 in mice lacking Nfix, and is fully penetrant by P20. Furthermore, we examined the subcommissural organ (SCO), the Sylvian aqueduct and the ependymal layer of the lateral ventricles, regions that when malformed and functionally perturbed have previously been implicated in the development of hydrocephalus. SOX3 is a factor known to regulate SCO development. Although we revealed that NFIX could repress Sox3-promoter-driven transcriptional activity in vitro, SOX3 expression within the SCO was normal within Nfix(-/-) mice, and Nfix mutant mice showed no abnormalities in the structure or function of the SCO. Moreover, these mutant mice exhibited no overt blockage of the Sylvian aqueduct. However, the ependymal layer of the lateral ventricles was frequently absent in Nfix(-/-) mice, suggesting that this phenotype may underlie the development of hydrocephalus within these knockout mice.

  5. Reality-and-Desire in Ciliates

    Science.gov (United States)

    Brijder, Robert; Hoogeboom, Hendrik Jan

    The theory of gene assembly in ciliates has a number of similarities with the theory of sorting by reversal. Both theories model processes that are based on splicing, and have a fixed begin and end product. The main difference is the type of splicing operations used to obtain the end product from the begin product. In this overview paper, we show how the concept of breakpoint graph, known from the theory of sorting by reversal, can be used in the theory of gene assembly. Our aim is to present the material in an intuitive and informal manner to allow for an efficient introduction into the subject.

  6. The Clinical Significance of Ependymal Enhancement at Presentation in Patients with Malignant Glioma

    Science.gov (United States)

    Kaidar-Person, Orit; Darawshe, Firas; Tzuk-Shina, Tzahala; Eran, Ayelet

    2015-01-01

    Introduction The current study evaluated the rate of ependymal enhancement and whether its presence influences survival of patients with malignant glioma (GBM). Methods A retrospective review of all patients who were treated in our institution from 2005 to 2011 was conducted. Data extracted from the medical records included age, date of diagnosis, co-morbidities, treatment regimen, and time of death. Magnetic resonance images (MRI) were evaluated for the presence of ependymal enhancement and its extent, and the correlation to survival was investigated. Results Between 2005 and 2011, 230 patients were treated for GBM. Eighty-nine patients were excluded from the study due to insufficient data, leaving 141 patients for analysis. Median age at diagnosis was 60 years. Sixty-seven (40.6%) patients had evidence of ependymal enhancement on MRI (group A), and 70 (42.4%) patients did not have evidence of enhancement. The assessment of ependymal enhancement was inconclusive due to mass effect and ventricular compression that precluded accurate assessment for 28 (17%) patients (group C). Median survival was 14 months for group A (range, 12–16 months), 15.9 months for group B (range, 14.28–17.65 months), and 11.7 months for group C (range, 6.47–16.92 months) (P>0.05). A multivariate analysis to predict survival indicated that male gender (P=0.039), hypertension (P=0.012), and biopsy only compared to complete gross tumor resection (P=0.001) were significant for poor survival. Conclusions Pretreatment ependymal enhancement on MRI was not found to be associated with poorer survival. These results might be due to better treatments options compared to prior reports. PMID:26886770

  7. The Clinical Significance of Ependymal Enhancement at Presentation in Patients with Malignant Glioma

    Directory of Open Access Journals (Sweden)

    Orit Kaidar-Person

    2015-10-01

    Full Text Available Introduction. The current study evaluated the rate of ependymal enhancement and whether its presence influences survival of patients with malignant glioma (GBM. Methods. A retrospective review of all patients who were treated in our institution from 2005 to 2011 was conducted. Data extracted from the medical records included age, date of diagnosis, co-morbidities, treatment regimen, and time of death. Magnetic resonance images (MRI were evaluated for the presence of ependymal enhancement and its extent, and the correlation to survival was investigated. Results. Between 2005 and 2011, 230 patients were treated for GBM. Eighty-nine patients were excluded from the study due to insufficient data, leaving 141 patients for analysis. Median age at diagnosis was 60 years. Sixty-seven (40.6% patients had evidence of ependymal enhancement on MRI (group A, and 70 (42.4% patients did not have evidence of enhancement. The assessment of ependymal enhancement was inconclusive due to mass effect and ventricular compression that precluded accurate assessment for 28 (17% patients (group C. Median survival was 14 months for group A (range, 12–16 months, 15.9 months for group B (range, 14.28–17.65 months, and 11.7 months for group C (range, 6.47–16.92 months (P>0.05. A multivariate analysis to predict survival indicated that male gender (P=0.039, hypertension (P=0.012, and biopsy only compared to complete gross tumor resection (P=0.001 were significant for poor survival. Conclusions. Pretreatment ependymal enhancement on MRI was not found to be associated with poorer survival. These results might be due to better treatments options compared to prior reports.

  8. Population dynamics of active and total ciliate populations in arable soil amended with wheat

    DEFF Research Database (Denmark)

    Ekelund, F.; Frederiksen, Helle B.; Ronn, R.

    2002-01-01

    of ciliate growth, the population of cystic ciliates increased 100-fold. We suggest that internal population regulation is the major factor governing ciliate encystment and that the rate of encystment depends on ciliate density. This model provides a quantitative explanation of ciliatostasis and can explain...

  9. SPECIES COMPOSITION OF PSAMMOPHILIC CILIATES OF SUMGAIT CASPIAN COAST

    Directory of Open Access Journals (Sweden)

    I. Kh. Alekperov

    2014-01-01

    Full Text Available Abstract. Comparative data on the species composition and species saprobic indicators of the psammon ciliates from Sumgait coast of the Caspian Sea are given.Methods. “Alive” samples were collected using a small clean plastic wide mouth bottles. Further processing was carried out under laboratory conditions. Small quantities of soil were examined under a binocular microscope MBS-9 . Ciliates detected microvessel caught and fixed castors for further impregnation kinetoma silver nitrate (Chatton et Lwoff, 1930 or silver proteinate. To determine the keys for ciliates used Foyssner’s major publications (Foissner et al., 1991, 1992, 1999 and “Free-living ciliates Atlas” (Alekperov, 2005.Results. We observed 75 species of ciliates during the studies, which species composition and distribution of the collection points are shown in table 1. Diagrams with average data were made relations groups psammophilous ciliates indicators saprobity different zones for each of the sites investigated Sumgait coast.Main conclusions. Environmental analysis using benthic ciliates indicators saprobity different zones showed that as expected, the industrial zone of Sumgayit coast coast, despite the decline in recent years, the total amount of pollution that is still highly contaminated portion of the coastal zone of the Caspian Sea.

  10. Ciliates learn to diagnose and correct classical error syndromes in mating strategies

    Directory of Open Access Journals (Sweden)

    Kevin Bradley Clark

    2013-08-01

    Full Text Available Preconjugal ciliates learn classical repetition error-correction codes to safeguard mating messages and replies from corruption by rivals and local ambient noise. Because individual cells behave as memory channels with Szilárd engine attributes, these coding schemes also might be used to limit, diagnose, and correct mating-signal errors due to noisy intracellular information processing. The present study, therefore, assessed whether heterotrich ciliates effect fault-tolerant signal planning and execution by modifying engine performance, and consequently entropy content of codes, during mock cell-cell communication. Socially meaningful serial vibrations emitted from an ambiguous artificial source initiated ciliate behavioral signaling performances known to advertise mating fitness with varying courtship strategies. Microbes, employing calcium-dependent Hebbian-like decision making, learned to diagnose then correct error syndromes by recursively matching Boltzmann entropies between signal planning and execution stages via power or refrigeration cycles. All eight serial contraction and reversal strategies incurred errors in entropy magnitude by the execution stage of processing. Absolute errors, however, subtended expected threshold values for single bit-flip errors in three-bit replies, indicating coding schemes protected information content throughout signal production. Ciliate preparedness for vibrations selectively and significantly affected the magnitude and valence of Szilárd engine performance during modal and nonmodal strategy corrective cycles. But entropy fidelity for all replies mainly improved across learning trials as refinements in engine efficiency. Fidelity neared maximum levels for only modal signals coded in resilient three-bit repetition error-correction sequences. Together, these findings demonstrate microbes can elevate survival/reproductive success by learning to implement classical fault-tolerant information processing in

  11. Hydrodynamical entrapment of ciliates at the air-liquid interface

    Science.gov (United States)

    Ferracci, Jonathan; Ueno, Hironori; Numayama-Tsuruta, Keiko; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

    2012-11-01

    We found the new phenomenon of the entrapment of ciliates at the air-water interface, though they are not trapped by a solid interface. We first characterize the behaviours of cells at the interface by comparing it to those away from interfaces. The results showed that the cell's swimming velocity is considerably reduced at the air-water interface. In order to experimentally verify the possible physiological causes of the entrapment, we observed their behaviours in absence of positive chemotaxis for oxygen and the negative geotaxis. The results illustrated that the entrapment phenomenon was not dependent on these physiological conditions. The experiments using surfactant revealed that the entrapment phenomenon was strongly affected by the velocity-stress conditions at the interface. This fact was confirmed numerically by a boundary element method, i.e. the stress-free condition at the air-liquid interface is one of the main mechanisms of the entrapment phenomenon found in the experiments. Since the entrapment phenomenon found in this study affects the cell-cell interactions and the mass transport at the interface, the knowledge obtained in this study is useful for better understanding the complex behaviours of swimming microorganisms in nature. PhD student in the Physiological Flow Studies Laboratory.

  12. Necessity Is the Mother of Invention: Ciliates, Transposons, and Transgenerational Inheritance.

    Science.gov (United States)

    Allen, Sarah E; Nowacki, Mariusz

    2017-03-01

    Ciliates are a fascinating model system for the study of the interaction between eukaryotic germlines and somatic lines, especially with regard to the invasion and defence against transposable elements. They separate their germline and somatic line into two nuclei within the same cell, and they silence transposons and repetitive elements by way of deleting them from their somatic genome. This large-scale deletion event uses a series of intricate sequence targeting pathways involving small RNAs and transposases, part of which consists of a transnuclear comparison between maternal soma and daughter germline. We present recent progress in this dynamic field, and argue that these DNA targeting pathways provide an optimal system for the transgenerational inheritance of acquired traits. Ciliates thus also demonstrate the evolutionary value of transposable elements, both as sources of sequence diversity and also as drivers of adaptive evolution by necessitating defensive systems.

  13. Lethal giant larvae 2 regulates development of the ciliated organ Kupffer's vesicle.

    Science.gov (United States)

    Tay, Hwee Goon; Schulze, Sabrina K; Compagnon, Julien; Foley, Fiona C; Heisenberg, Carl-Philipp; Yost, H Joseph; Abdelilah-Seyfried, Salim; Amack, Jeffrey D

    2013-04-01

    Motile cilia perform crucial functions during embryonic development and throughout adult life. Development of organs containing motile cilia involves regulation of cilia formation (ciliogenesis) and formation of a luminal space (lumenogenesis) in which cilia generate fluid flows. Control of ciliogenesis and lumenogenesis is not yet fully understood, and it remains unclear whether these processes are coupled. In the zebrafish embryo, lethal giant larvae 2 (lgl2) is expressed prominently in ciliated organs. Lgl proteins are involved in establishing cell polarity and have been implicated in vesicle trafficking. Here, we identified a role for Lgl2 in development of ciliated epithelia in Kupffer's vesicle, which directs left-right asymmetry of the embryo; the otic vesicles, which give rise to the inner ear; and the pronephric ducts of the kidney. Using Kupffer's vesicle as a model ciliated organ, we found that depletion of Lgl2 disrupted lumen formation and reduced cilia number and length. Immunofluorescence and time-lapse imaging of Kupffer's vesicle morphogenesis in Lgl2-deficient embryos suggested cell adhesion defects and revealed loss of the adherens junction component E-cadherin at lateral membranes. Genetic interaction experiments indicate that Lgl2 interacts with Rab11a to regulate E-cadherin and mediate lumen formation that is uncoupled from cilia formation. These results uncover new roles and interactions for Lgl2 that are crucial for both lumenogenesis and ciliogenesis and indicate that these processes are genetically separable in zebrafish.

  14. Lethal giant larvae 2 regulates development of the ciliated organ Kupffer’s vesicle

    Science.gov (United States)

    Tay, Hwee Goon; Schulze, Sabrina K.; Compagnon, Julien; Foley, Fiona C.; Heisenberg, Carl-Philipp; Yost, H. Joseph; Abdelilah-Seyfried, Salim; Amack, Jeffrey D.

    2013-01-01

    Motile cilia perform crucial functions during embryonic development and throughout adult life. Development of organs containing motile cilia involves regulation of cilia formation (ciliogenesis) and formation of a luminal space (lumenogenesis) in which cilia generate fluid flows. Control of ciliogenesis and lumenogenesis is not yet fully understood, and it remains unclear whether these processes are coupled. In the zebrafish embryo, lethal giant larvae 2 (lgl2) is expressed prominently in ciliated organs. Lgl proteins are involved in establishing cell polarity and have been implicated in vesicle trafficking. Here, we identified a role for Lgl2 in development of ciliated epithelia in Kupffer’s vesicle, which directs left-right asymmetry of the embryo; the otic vesicles, which give rise to the inner ear; and the pronephric ducts of the kidney. Using Kupffer’s vesicle as a model ciliated organ, we found that depletion of Lgl2 disrupted lumen formation and reduced cilia number and length. Immunofluorescence and time-lapse imaging of Kupffer’s vesicle morphogenesis in Lgl2-deficient embryos suggested cell adhesion defects and revealed loss of the adherens junction component E-cadherin at lateral membranes. Genetic interaction experiments indicate that Lgl2 interacts with Rab11a to regulate E-cadherin and mediate lumen formation that is uncoupled from cilia formation. These results uncover new roles and interactions for Lgl2 that are crucial for both lumenogenesis and ciliogenesis and indicate that these processes are genetically separable in zebrafish. PMID:23482490

  15. Methods for the cultivation of ciliated protozoa from the large intestine of horses.

    Science.gov (United States)

    Bełżecki, Grzegorz; Miltko, Renata; Michałowski, Tadeusz; McEwan, Neil R

    2016-01-01

    This paper describes cultivation methods for ciliates from the digestive tract of horses. Members of three different genera were successfully grown in vitro for short periods of time. However, only cells belonging to the genus Blepharocorys, which resides in the horse's large intestine, were maintained for longer periods. This Blepharocorys culture was successfully grown in vitro after inoculation of freshly excreted horse faeces in culture medium containing a population of bacteria. The ciliates survived for over six months, and the density of their population varied between 1.7 × 10(3) and 2.4 × 10(3) cells mL(-1). Favourable conditions for the prolonged cultivation of this ciliate were observed when the medium was prepared by mixing horse faeces and 'caudatum' salt solution in a 1:1 V/V ratio together with food (60% powdered meadow hay, 16% wheat gluten, 12% barley flour and 12% microcrystalline cellulose) supplied as 0.20 mg mL(-1) culture per day.

  16. The ability of the rumen ciliate protozoan Diploplastron affine to digest and ferment starch.

    Science.gov (United States)

    Wereszka, K; Michałowski, T

    2012-07-01

    The ciliate Diploplastron affine is known as a common species of the rumen fauna in cattle and sheep. This protozoon is able to digest cellulose, whereas its amylolytic activity is not well known. The objective of the reported studies was to examine the ability of D. affine to digest starch and to use this polysaccharide to cover the requirement for energy. The enzymatic studies showed that the protozoal cell extract degraded starch to reducing products with the rate being equivalent to 2.4 ± 0.47 μmol/L glucose per mg protein per min. Maltose, maltotriose and a small quantity of glucose were the end products of starch degradation. The degradation rate of maltose was only 0.05 μmol/L glucose per mg protein per min. Two peaks in α-amylase and a single peak in maltase activity were found following molecular filtration of ciliate cell extract, whereas three starch-degrading enzymes were identified by a zymographic technique. Incubation of the bacteria-free ciliates with starch in the presence of antibiotics resulted in a release of volatile fatty acids with the net rate of 25 pmol per protozoan per h. Acetic acid followed by butyric acid was the main product of starch fermentation. The results confirmed the ability of D. affine to utilize starch in energy-yielding processes.

  17. Studies on experimental culture of a marine ciliate Fabrea salina

    Digital Repository Service at National Institute of Oceanography (India)

    Rattan, R.; Ansari, Z.A.; Chatterji, A.

    Studies were conducted on the culture of a marine ciliate, Fabrea salina in the laboratory condition. Three types of inert feed; commercial yeast, fermented wheat bran and fermented rise bran were tested to study their suitability as artificial feed...

  18. Impact of Soil Texture on Soil Ciliate Communities

    Science.gov (United States)

    Chau, J. F.; Brown, S.; Habtom, E.; Brinson, F.; Epps, M.; Scott, R.

    2014-12-01

    Soil water content and connectivity strongly influence microbial activities in soil, controlling access to nutrients and electron acceptors, and mediating interactions between microbes within and between trophic levels. These interactions occur at or below the pore scale, and are influenced by soil texture and structure, which determine the microscale architecture of soil pores. Soil protozoa are relatively understudied, especially given the strong control they exert on bacterial communities through predation. Here, ciliate communities in soils of contrasting textures were investigated. Two ciliate-specific primer sets targeting the 18S rRNA gene were used to amplify DNA extracted from eight soil samples collected from Sumter National Forest in western South Carolina. Primer sets 121F-384F-1147R (semi-nested) and 315F-959R were used to amplify soil ciliate DNA via polymerase chain reaction (PCR), and the resulting PCR products were analyzed by gel electrophoresis to obtain quantity and band size. Approximately two hundred ciliate 18S rRNA sequences were obtained were obtained from each of two contrasting soils. Sequences were aligned against the NCBI GenBank database for identification, and the taxonomic classification of best-matched sequences was determined. The ultimate goal of the work is to quantify changes in the ciliate community under short-timescale changes in hydrologic conditions for varying soil textures, elucidating dynamic responses to desiccation stress in major soil ciliate taxa.

  19. Chromosome copy number variation and control in the ciliate Chilodonella uncinata.

    Directory of Open Access Journals (Sweden)

    Kevin J Spring

    Full Text Available Copy number variations are widespread in eukaryotes. The unusual genome architecture of ciliates, in particular, with its process of amitosis in macronuclear division, provides a valuable model in which to study copy number variation. The current model of amitosis envisions stochastic distribution of macronuclear chromosomes during asexual reproduction. This suggests that amitosis is likely to result in high levels of copy number variation in ciliates, as dividing daughter cells can have variable copy numbers of chromosomes if chromosomal distribution during amitosis is a stochastic process. We examined chromosomal distribution during amitosis in Chilodonella uncinata, a ciliate with gene-size macronuclear chromosomes. We quantified 4 chromosomes in evolving populations of C. uncinata and modeled the amitotic distribution process. We found that macronuclear chromosomes differ in copy number from one another but that copy number does not change as expected under a stochastic process. The chromosome carrying SSU increased in copy number, which is consistent with selection to increase abundance; however, two other studied chromosomes displayed much lower than expected among-line variance. Our models suggest that balancing selection is sufficient to explain the observed maintenance of chromosome copy during asexual reproduction.

  20. The trophic role and impact of plankton ciliates in the microbial web structure of a tropical polymictic lake dominated by filamentous cyanobacteria

    Directory of Open Access Journals (Sweden)

    Alfonso Esquivel

    2016-03-01

    Full Text Available The recent interest in the plankton structures and dynamics in tropical and subtropical lakes has revealed important trends that set these lakes apart from temperate lakes, and one of the main differences is the enhanced importance of the microbial food web with respect to net plankton. Ciliates are a key component of subtropical and tropical microbial webs because of their role as dominant picoplankton grazers and their ability to channel picoplankton production to the uppermost trophic levels. Plankton ciliates have been found to play a crucial role in the survival of fish larvae in lakes that share several features with Lake Catemaco, a eutrophic tropical Mexican lake. Therefore, the plankton ciliate composition, abundance, and biomass of Lake Catemaco were studied to assess their role in the microbial food web. The data were obtained from surface and bottom water samples collected at eleven points during three surveys in 2011 and an additional survey in 2013, with the surveys covering the local climatic seasons. The most abundant components of the plankton ciliate assemblages were small prostomatids (Urotricha spp., choreotrichs (Rimostrombidium spp., cyclotrichs (Mesodinium and Askenasia, and scuticociliates (Cyclidium, Cinetochilum, Pleuronema, and Uronema. Other important ciliates in terms of abundance and/or biomass were haptorids (Actinobolina, Belonophrya, Monodinium, Paradileptus, and Laginophrya, Halteria, oligotrichs (Limnostrombidium and Pelagostrombidium, Linostomella, Bursaridium, Cyrtolophosis, and Litonotus. The ciliate abundance averaged 57 cells mL-1 and ranged from 14 to 113 cells mL-1. The mean ciliate biomass was 71 µg C L-1 and ranged from 10 to 202 µg C L-1. Differences were not detected in ciliate abundance or biomass between the sampling points or sampling depths (surface to bottom; however, significant differences were observed between seasons for both variables. Nano-sized filamentous cyanobacteria were the most

  1. Mechanical strain determines the axis of planar polarity in ciliated epithelia

    OpenAIRE

    2015-01-01

    Epithelia containing multiciliated cells align beating cilia along a common planar axis specified by the conserved planar cell polarity (PCP) pathway. Specification of the planar axis is also thought to require a long-range cue to align the axis globally, but the nature of this cue in ciliated and other epithelia remains poorly understood. We examined this issue using the Xenopus larval skin where ciliary flow aligns to the anterior-posterior (A-P) axis. We first show that a planar axis initi...

  2. Influence of ciliated protozoa and heterotrophic nanoflagellates on the fate of primary production in the northeast Atlantic Ocean

    Science.gov (United States)

    Karayanni, Hera; Christaki, Urania; van Wambeke, France; Denis, Michel; Moutin, Thierry

    2005-07-01

    Heterotrophic nanoflagellates and ciliates and their herbivorous activity were studied within the framework of the Programme Océan Multidisciplinaire Méso Echelle (POMME) in the northeastern Atlantic between 16°-22°W and 38°-45°N during winter, spring, and late summer/autumn 2001. Ciliate ingestion rates of Synechococcus and eukaryotic algae were measured using fluorescently labeled prey. Heterotrophic nanoflagellate ingestion rates of Synechococcus and Prochlorococcus were also estimated. Heterotrophic nanoflagellate and ciliate standing stock within the surface layer (0-100 m) showed seasonal variation, with maximal values in spring (866 mg C m-2 and 637 mg C m-2, respectively). Oligotrichs dominated the ciliate assemblages, except at one site visited during spring, where a tintinnid bloom was observed. Ingestion of photosynthetic cells less than 10 μm in size was positively correlated (r = 0.7, p consumption reflected differences in the evolution of the phytoplankton bloom and in the structure of the microbial food web, both associated with the strong mesoscale hydrodynamic variability of the study area. In that context it is worthy to note that when tintinnids reached high abundances locally (1260 cells L-1), their impact as phytoplankton grazers was important and reached 69% of primary production. Generally, heterotrophic nanoflagellates and ciliates were relatively more important in determining the fate of phytogenic carbon during spring. Another interesting feature of primary production consumption was that during the autumn, when Prochlorococcus dominated the phytoplankton community, the protozoan grazing activity was ineffective in regulating the fate of primary producers.

  3. The role of ciliate protozoa in the rumen

    Directory of Open Access Journals (Sweden)

    Charles James Newbold

    2015-11-01

    Full Text Available First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50% of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear.Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fibre degradation. The development of techniques to clone and express ciliate genes in  phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterisation of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30% and reduces methane production by up to 11%. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small entodiniium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described.

  4. The Role of Ciliate Protozoa in the Rumen.

    Science.gov (United States)

    Newbold, Charles J; de la Fuente, Gabriel; Belanche, Alejandro; Ramos-Morales, Eva; McEwan, Neil R

    2015-01-01

    First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50% of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear. Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fiber degradation. The development of techniques to clone and express ciliate genes in λ phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterization of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30% and reduces methane production by up to 11%. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small Entodinium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described.

  5. Colonization dynamics of ciliate morphotypes modified by shifting sandy sediments.

    Science.gov (United States)

    Risse-Buhl, Ute; Felsmann, Katja; Mutz, Michael

    2014-08-01

    Sandy stream-bed sediments colonized by a diverse ciliate community are subject to various disturbance regimes. In microcosms, we investigated the effect of sediment shifting on the colonization dynamics of 3 ciliate morphotypes differing in morphology, behavior and feeding strategy. The dynamics of the ciliate morphotypes inhabiting sediment pore water and overlying water were observed at 3 sediment shifting frequencies: (1) stable sediments, (2) periodically shifting sediments such as migrating ripples, and (3) continuously shifting sediments as occurring during scour events of the uppermost sediment. Sediment shifting significantly affected the abundance and growth rate of the ciliate morphotypes. The free-swimming filter feeder Dexiostoma campylum was vulnerable to washout by sediment shifting since significantly higher numbers occurred in the overlying water than in pore water. Abundance of D. campylum only increased in pore water of stable sediments. On the contrary, the vagile grasper feeder Chilodonella uncinata and the sessile filter feeder Vorticella convallaria had positive growth rates and successfully colonized sediments that shifted periodically and continuously. Thus, the spatio-temporal pattern of sediment dynamics acts as an essential factor of impact on the structure, distribution and function of ciliate communities in sand-bed streams.

  6. Evaluation of lugol solution used for counting rumen ciliates

    Directory of Open Access Journals (Sweden)

    Marta D'Agosto

    1999-01-01

    Full Text Available The present study proposes a modification of the technique described by PURSER & MOIR (1959 for the quantitative evaluation of rumen ciliate based on an adaptation described by DEHORITY (I984. The modifying process includes: the replacement of two drops of brilliant green dye, for at least four hours, by three drops of lugol solution, for at least 15 minutes. It was made a comparative evaluation of these stainings. It was concluded that lugol solution can replace the brilliant green dye showing the following advantages: staining time reduction and subsequent speeding of sample processing; evidence of skeletal plates of entodiniomorphs making its identification easier; improved observation of small ciliates and inconspicuous structures; improved total counting and generic identification of the ciliates.

  7. The ependyma of goat. II. Ependymal lining of the lateral ventricles, mesencephalic canal, and fourth ventricle: scanning electron microscopic study.

    Science.gov (United States)

    Rajtová, V

    1990-01-01

    The ependymal surface of the lateral cerebral ventricle, mesencephalic canal, and IVth ventricle of 13 male and female goats were studied by means of scanning electron microscopy. The lateral cerebral ventricle was covered mostly with thin cilia that might have club-like terminations on nucleus caudatus, the wide "naked" places with bleb-like protrusions occurred in the transition to cornu temporale during anestrous cycle. The ependymal surface of mesencephalic canal of female goats during anestrus was covered with abundant spherical protrusions. No other changes that could be related to the sexual differences were found.

  8. An approach to measure ciliate grazing on living heterotrophic nanoflagellates

    DEFF Research Database (Denmark)

    Christoffersen, K.; González, J. M.

    2003-01-01

    . Here we present an approach for the assessment of ciliate grazing on living heterotrophic nanoflagellates. Stationary phase cultures of a heterotrophic nanoflagellate (Cafeteria sp.) were live-stained by allowing them to take up fluorescently labelled macromolecules. Controls revealed that this label...

  9. Transposon domestication versus mutualism in ciliate genome rearrangements.

    Directory of Open Access Journals (Sweden)

    Alexander Vogt

    Full Text Available Ciliated protists rearrange their genomes dramatically during nuclear development via chromosome fragmentation and DNA deletion to produce a trimmer and highly reorganized somatic genome. The deleted portion of the genome includes potentially active transposons or transposon-like sequences that reside in the germline. Three independent studies recently showed that transposase proteins of the DDE/DDD superfamily are indispensible for DNA processing in three distantly related ciliates. In the spirotrich Oxytricha trifallax, high copy-number germline-limited transposons mediate their own excision from the somatic genome but also contribute to programmed genome rearrangement through a remarkable transposon mutualism with the host. By contrast, the genomes of two oligohymenophorean ciliates, Tetrahymena thermophila and Paramecium tetraurelia, encode homologous PiggyBac-like transposases as single-copy genes in both their germline and somatic genomes. These domesticated transposases are essential for deletion of thousands of different internal sequences in these species. This review contrasts the events underlying somatic genome reduction in three different ciliates and considers their evolutionary origins and the relationships among their distinct mechanisms for genome remodeling.

  10. Flow induced by ependymal cilia dominates near-wall cerebrospinal fluid dynamics in the lateral ventricles.

    Science.gov (United States)

    Siyahhan, Bercan; Knobloch, Verena; de Zélicourt, Diane; Asgari, Mahdi; Schmid Daners, Marianne; Poulikakos, Dimos; Kurtcuoglu, Vartan

    2014-05-06

    While there is growing experimental evidence that cerebrospinal fluid (CSF) flow induced by the beating of ependymal cilia is an important factor for neuronal guidance, the respective contribution of vascular pulsation-driven macroscale oscillatory CSF flow remains unclear. This work uses computational fluid dynamics to elucidate the interplay between macroscale and cilia-induced CSF flows and their relative impact on near-wall dynamics. Physiological macroscale CSF dynamics are simulated in the ventricular space using subject-specific anatomy, wall motion and choroid plexus pulsations derived from magnetic resonance imaging. Near-wall flow is quantified in two subdomains selected from the right lateral ventricle, for which dynamic boundary conditions are extracted from the macroscale simulations. When cilia are neglected, CSF pulsation leads to periodic flow reversals along the ventricular surface, resulting in close to zero time-averaged force on the ventricle wall. The cilia promote more aligned wall shear stresses that are on average two orders of magnitude larger compared with those produced by macroscopic pulsatile flow. These findings indicate that CSF flow-mediated neuronal guidance is likely to be dominated by the action of the ependymal cilia in the lateral ventricles, whereas CSF dynamics in the centre regions of the ventricles is driven predominantly by wall motion and choroid plexus pulsation.

  11. Macronuclear genome structure of the ciliate Nyctotherus ovalis: Single-gene chromosomes and tiny introns

    Directory of Open Access Journals (Sweden)

    Landweber Laura F

    2008-12-01

    Full Text Available Abstract Background Nyctotherus ovalis is a single-celled eukaryote that has hydrogen-producing mitochondria and lives in the hindgut of cockroaches. Like all members of the ciliate taxon, it has two types of nuclei, a micronucleus and a macronucleus. N. ovalis generates its macronuclear chromosomes by forming polytene chromosomes that subsequently develop into macronuclear chromosomes by DNA elimination and rearrangement. Results We examined the structure of these gene-sized macronuclear chromosomes in N. ovalis. We determined the telomeres, subtelomeric regions, UTRs, coding regions and introns by sequencing a large set of macronuclear DNA sequences (4,242 and cDNAs (5,484 and comparing them with each other. The telomeres consist of repeats CCC(AAAACCCCn, similar to those in spirotrichous ciliates such as Euplotes, Sterkiella (Oxytricha and Stylonychia. Per sequenced chromosome we found evidence for either a single protein-coding gene, a single tRNA, or the complete ribosomal RNAs cluster. Hence the chromosomes appear to encode single transcripts. In the short subtelomeric regions we identified a few overrepresented motifs that could be involved in gene regulation, but there is no consensus polyadenylation site. The introns are short (21–29 nucleotides, and a significant fraction (1/3 of the tiny introns is conserved in the distantly related ciliate Paramecium tetraurelia. As has been observed in P. tetraurelia, the N. ovalis introns tend to contain in-frame stop codons or have a length that is not dividable by three. This pattern causes premature termination of mRNA translation in the event of intron retention, and potentially degradation of unspliced mRNAs by the nonsense-mediated mRNA decay pathway. Conclusion The combination of short leaders, tiny introns and single genes leads to very minimal macronuclear chromosomes. The smallest we identified contained only 150 nucleotides.

  12. ATP4 and ciliation in the neuroectoderm and endoderm of Xenopus embryos and tadpoles

    Directory of Open Access Journals (Sweden)

    Peter Walentek

    2015-09-01

    Full Text Available During gastrulation and neurulation, foxj1 expression requires ATP4a-dependent Wnt/β-catenin signaling for ciliation of the gastrocoel roof plate (Walentek et al. Cell Rep. 1 (2012 516–527. and the mucociliary epidermis (Walentek et al. Dev. Biol. (2015 of Xenopus laevis embryos. These data suggested that ATP4a and Wnt/β-catenin signaling regulate foxj1 throughout Xenopus development. Here we analyzed whether foxj1 expression was also ATP4a-dependent in other ciliated tissues of the developing Xenopus embryo and tadpole. We found that in the floor plate of the neural tube ATP4a-dependent canonical Wnt signaling was required for foxj1 expression, downstream of or in parallel to Hedgehog signaling. In the developing tadpole brain, ATP4-function was a prerequisite for the establishment of cerebrospinal fluid flow. Furthermore, we describe foxj1 expression and the presence of multiciliated cells in the developing tadpole gastrointestinal tract. Our work argues for a general requirement of ATP4-dependent Wnt/β-catenin signaling for foxj1 expression and motile ciliogenesis throughout Xenopus development.

  13. Evaluation of Enrichment Protocols for Bacterial Endosymbionts of Ciliates by Real-Time PCR.

    Science.gov (United States)

    Castelli, Michele; Lanzoni, Olivia; Rossi, Leonardo; Potekhin, Alexey; Schrallhammer, Martina; Petroni, Giulio

    2016-06-01

    Large-scale studies on obligate bacterial endosymbionts may frequently require preliminary purification and enrichment protocols, which are often elaborate to set up and to evaluate, especially if the host organism is a protist. The purpose of this study was to develop a real-time PCR-based strategy and employ it for assessing two of such enrichment protocols for Holospora caryophila, hosted by the ciliate Paramecium. Four SSU rRNA gene-targeted real-time PCR assays were designed, which allowed to compare the amount of H. caryophila to other organisms, namely the host, its food bacterium (Raoultella planticola), and free-living bacteria present in the culture medium. By the use of the real-time PCR assays in combination, it was possible to conclude that the "cell fractionation" protocol was quite successful in the enrichment of the symbiont, while the "Percoll gradient" protocol will need further refinements to be fully repeatable. The proposed approach has the potential to facilitate and encourage future studies on the yet underexplored field of bacterial endosymbionts of ciliates and other protists. It can also find valuable applications for experimental questions other than those tested, such as fast and precise assessment of symbiont abundance in natural populations and comparison among multiple coexisting symbionts.

  14. Differential localization and functional specialization of centrin analogs in the parasitic ciliate Trichodina pediculus.

    Science.gov (United States)

    Viguès, Bernard; Colombet, Jonathan; Damaj, Raghida

    2016-09-01

    Trichodinids are ciliated protozoans that reversibly attach to the tegument of marine and freshwater host-organisms via an adhesive disc. In this study, we have used permeabilized cell models of Trichodina pediculus to examine the distribution of centrins, a Ca(2+)-binding protein associated with centrioles and/or contractile filamentous structures in a large number of protists. The previous finding that filamentous material of the adhesive disc comprised a 23-kDa centrin analog suggested that this protein might be a disc-specific isoform. This possibility was explored through immunolabeling methods using two distinct antibodies, anti-ecto-endoplasmic boundary (EEB) and anti-Hscen2 previously shown to react respectively with centrin-based filament networks and with centrioles. Immunofluorescence microscopy showed that anti-EEB reacts with filamentous material of the disc but not with basal bodies. Conversely, anti-Hscen2 cross-reacted with basal bodies but failed to label any type of structure occurring in the disc area. More detailed data on localization of this protein was obtained by immunoelectron microscopy showing gold particles deposits in the lumen of basal bodies. The different patterns revealed by this immunochemical approach suggest that the two protein antigens concerned by this study are distinct centrin isoforms that presumably perform organelle-specific function in the ciliate T. pediculus.

  15. Structures, biological activities and phylogenetic relationships of terpenoids from marine ciliates of the genus Euplotes.

    Science.gov (United States)

    Guella, Graziano; Skropeta, Danielle; Di Giuseppe, Graziano; Dini, Fernando

    2010-07-08

    In the last two decades, large scale axenic cell cultures of the marine species comprising the family Euplotidae have resulted in the isolation of several new classes of terpenoids with unprecedented carbon skeletons including the (i) euplotins, highly strained acetylated sesquiterpene hemiacetals; (ii) raikovenals, built on the bicyclo[3.2.0]heptane ring system; (iii) rarisetenolides and focardins containing an octahydroazulene moiety; and (iv) vannusals, with a unique C30 backbone. Their complex structures have been elucidated through a combination of nuclear magnetic resonance spectroscopy, mass spectrometry, molecular mechanics and quantum chemical calculations. Despite the limited number of biosynthetic experiments having been performed, the large diversity of ciliate terpenoids has facilitated the proposal of biosynthetic pathways whereby they are produced from classical linear precursors. Herein, the similarities and differences emerging from the comparison of the classical chemotaxonomy approach based on secondary metabolites, with species phylogenesis based on genetic descriptors (SSU-rDNA), will be discussed. Results on the interesting ecological and biological properties of ciliate terpenoids are also reported.

  16. Structures, Biological Activities and Phylogenetic Relationships of Terpenoids from Marine Ciliates of the Genus Euplotes

    Directory of Open Access Journals (Sweden)

    Fernando Dini

    2010-07-01

    Full Text Available In the last two decades, large scale axenic cell cultures of the marine species comprising the family Euplotidae have resulted in the isolation of several new classes of terpenoids with unprecedented carbon skeletons including the (i euplotins, highly strained acetylated sesquiterpene hemiacetals; (ii raikovenals, built on the bicyclo[3.2.0]heptane ring system; (iii rarisetenolides and focardins containing an octahydroazulene moiety; and (iv vannusals, with a unique C30 backbone. Their complex structures have been elucidated through a combination of nuclear magnetic resonance spectroscopy, mass spectrometry, molecular mechanics and quantum chemical calculations. Despite the limited number of biosynthetic experiments having been performed, the large diversity of ciliate terpenoids has facilitated the proposal of biosynthetic pathways whereby they are produced from classical linear precursors. Herein, the similarities and differences emerging from the comparison of the classical chemotaxonomy approach based on secondary metabolites, with species phylogenesis based on genetic descriptors (SSU-rDNA, will be discussed. Results on the interesting ecological and biological properties of ciliate terpenoids are also reported.

  17. On computational properties of gene assembly in ciliates

    Directory of Open Access Journals (Sweden)

    Vladimir Rogojin

    2010-11-01

    Full Text Available Gene assembly in stichotrichous ciliates happening during sexual reproduction is one of the most involved DNA manipulation processes occurring in biology. This biological process is of high interest from the computational and mathematical points of view due to its close analogy with such concepts and notions in theoretical computer science as permutation and linked list sorting and string rewriting. Studies on computational properties of gene assembly in ciliates represent a good example of interdisciplinary research contributing to both computer science and biology. We review here a number of general results related both to the development of different computational methods enhancing our understanding on the nature of gene assembly, as well as to the development of new biologically motivated computational and mathematical models and paradigms. Those paradigms contribute in particular to combinatorics, formal languages and computability theories.

  18. Correlation between localization, age, and chromosomal imbalances in ependymal tumours as detected by CGH.

    Science.gov (United States)

    Jeuken, Judith W M; Sprenger, Sandra H E; Gilhuis, Job; Teepen, Hans L J M; Grotenhuis, Andre J; Wesseling, Pieter

    2002-06-01

    Ependymal tumours (ETs) are gliomas that arise from the ependymal lining of the cerebral ventricles and from the remnants of the central canal of the spinal cord. Both clinical and genetic studies suggest that distinct genetic subtypes of ETs exist, the subtypes being correlated with patient age and/or tumour site. In the present study, the tumour genome of 20 ETs (15 adult and five paediatric cases) was screened for chromosomal imbalances by comparative genomic hybridization (CGH). The most frequently detected imbalances were -22q (75%), -10q (65%), -21 (50%), -16p (50%), -1p (45%), +4q (45%), -10p (45%), -2q (40%), -6 (40%), -19 (40%), -2p (35%), -3p (35%), and -16q (35%). Comparison of the chromosomal imbalances detected in ETs with those previously reported in oligodendroglial and astrocytic tumours revealed that in this respect ETs show similarities to these other gliomas. By combining these results with those of a recent study of Zheng et al. and Hirose et al., it was found that although ETs from different sites and from adult and paediatric patients show overlap at the CGH level, some chromosomal imbalances occur predominantly in a certain category. In adult patients, spinal ETs relatively often showed +2, +7, +12, and -14q; infratentorial ETs -22; and supratentorial ETs -9. In addition, in posterior fossa ETs, -6 and +9 were much more frequent in adults than in children. It is concluded that the genetic background of ETs is complex and partly determined by tumour site, histopathological subtype, and age of the patient.

  19. Harmful Ciliates and Dominant Genus in Culture Ponds of Young Abalone

    Institute of Scientific and Technical Information of China (English)

    黄建荣; 徐润林; 廖家遗

    2004-01-01

    By using the methods of qualitative and quantitative analysis, the species composition and dominant genus of harmful, ciliates in young abalone culture ponds are studied. Totally 68 species of ciliates, belonging to 3 classes, 16 orders and 46 genus, are found. The dominant ciliate species are Aspidisca leptaspis, Vorticella sp. and Euplotes rariseta. During the young abalone cultivation, the numbers of young abalones increase first,and then show a trend of decreasing. The relationship between the density and composition of ciliates and the density of algae in the young abalone culture ponds is also discussed.

  20. Inter-annual ciliate distribution variation within the late stratification oxycline in a monomictic lake, Lake Alchichica (Mexico

    Directory of Open Access Journals (Sweden)

    Ximena Sánchez Medina

    2016-03-01

    Full Text Available noxia, and ciliates might play a very important role in the plankton community budget there. We analysed changes in the composition and biomass of the ciliate assemblage and other microbial loop components throughout the oxycline just at the end of stratification in a warm-monomictic lake, Lake Alchichica, Mexico (four samplings: 2006-2008, 2010; the results were compared with those obtained from another lake from the region, La Preciosa, sampled in 2010. Bacteria, autotrophic picoplankton (APP and flagellates were analysed using epifluorescence microscopy. Ciliates were evaluated either in DAPI stained samples (looking for pigmented organelles and/or ingested phototrophs or in quantitative protargol stain (QPS permanent preparations, where they were identified at the genus or species level. The end of the stratification period in Lake Alchichica was characterized by almost uniform heterotrophic picoplankton (HPP numbers (106 cells mL-1 throughout the water column. Meanwhile, APP showed epilimnetic and/or metalimnetic maxima of 105 cells mL-1 followed by an order of magnitude drop in the hypolimnion. A very important peak (105 cells mL-1 of the autotrophic or mixotrophic flagellate Pyramimonas sp. was observed repeatedly above and within the oxycline of Lake Alchichica. Ciliate biomass maxima were found around the oxycline and in the above-bottom layer. The top of the oxycline was dominated by Euplotes spp. and Spirostomum teres fine- to coarse-filter feeders (feeding upon APP, nanodiatoms and algae. Raptorial haptorids (in particular, Phialina sp. were the second most important group, generally occupying the layer below euplotids, followed by Holophrya and Prorodon facultative anaerobic prostomes. Sometimes, strictly anaerobic Caenomorpha sp. was found to be important in the anoxic hypolimnion. Minute picoplankton feeding species (both APP and heterotrophic bacteria feeders were important throughout the water column: in the epilimnion

  1. Prevalent ciliate symbiosis on copepods: high genetic diversity and wide distribution detected using small subunit ribosomal RNA gene.

    Science.gov (United States)

    Guo, Zhiling; Liu, Sheng; Hu, Simin; Li, Tao; Huang, Yousong; Liu, Guangxing; Zhang, Huan; Lin, Senjie

    2012-01-01

    Toward understanding the genetic diversity and distribution of copepod-associated symbiotic ciliates and the evolutionary relationships with their hosts in the marine environment, we developed a small subunit ribosomal RNA gene (18S rDNA)-based molecular method and investigated the genetic diversity and genotype distribution of the symbiotic ciliates on copepods. Of the 10 copepod species representing six families collected from six locations of Pacific and Atlantic Oceans, 9 were found to harbor ciliate symbionts. Phylogenetic analysis of the 391 ciliate 18S rDNA sequences obtained revealed seven groups (ribogroups), six (containing 99% of all the sequences) belonging to subclass Apostomatida, the other clustered with peritrich ciliate Vorticella gracilis. Among the Apostomatida groups, Group III were essentially identical to Vampyrophrya pelagica, and the other five groups represented the undocumented ciliates that were close to Vampyrophrya/Gymnodinioides/Hyalophysa. Group VI ciliates were found in all copepod species but one (Calanus sinicus), and were most abundant among all ciliate sequences obtained, indicating that they are the dominant symbiotic ciliates universally associated with copepods. In contrast, some ciliate sequences were found only in some of the copepods examined, suggesting the host selectivity and geographic differentiation of ciliates, which requires further verification by more extensive sampling. Our results reveal the wide occurrence and high genetic diversity of symbiotic ciliates on marine copepods and highlight the need to systematically investigate the host- and geography-based genetic differentiation and ecological roles of these ciliates globally.

  2. Prevalent ciliate symbiosis on copepods: high genetic diversity and wide distribution detected using small subunit ribosomal RNA gene.

    Directory of Open Access Journals (Sweden)

    Zhiling Guo

    Full Text Available Toward understanding the genetic diversity and distribution of copepod-associated symbiotic ciliates and the evolutionary relationships with their hosts in the marine environment, we developed a small subunit ribosomal RNA gene (18S rDNA-based molecular method and investigated the genetic diversity and genotype distribution of the symbiotic ciliates on copepods. Of the 10 copepod species representing six families collected from six locations of Pacific and Atlantic Oceans, 9 were found to harbor ciliate symbionts. Phylogenetic analysis of the 391 ciliate 18S rDNA sequences obtained revealed seven groups (ribogroups, six (containing 99% of all the sequences belonging to subclass Apostomatida, the other clustered with peritrich ciliate Vorticella gracilis. Among the Apostomatida groups, Group III were essentially identical to Vampyrophrya pelagica, and the other five groups represented the undocumented ciliates that were close to Vampyrophrya/Gymnodinioides/Hyalophysa. Group VI ciliates were found in all copepod species but one (Calanus sinicus, and were most abundant among all ciliate sequences obtained, indicating that they are the dominant symbiotic ciliates universally associated with copepods. In contrast, some ciliate sequences were found only in some of the copepods examined, suggesting the host selectivity and geographic differentiation of ciliates, which requires further verification by more extensive sampling. Our results reveal the wide occurrence and high genetic diversity of symbiotic ciliates on marine copepods and highlight the need to systematically investigate the host- and geography-based genetic differentiation and ecological roles of these ciliates globally.

  3. Actin evolution in ciliates (Protist, Alveolata) is characterized by high diversity and three duplication events.

    Science.gov (United States)

    Yi, Zhenzhen; Huang, Lijuan; Yang, Ran; Lin, Xiaofeng; Song, Weibo

    2016-03-01

    Ciliates possess two distinct nuclear genomes and unique genomic features, including highly fragmented chromosomes and extensive chromosomal rearrangements. Recent transcriptomic surveys have revealed that ciliates have several multi-copy genes providing an ideal template to study gene family evolution. Nonetheless, this process remains little studied in ciliated protozoa and consequently, the evolutionary patterns that govern it are not well understood. In this study, we focused on obtaining fine-scale information relative to ciliate species divergence for the first time. A total of 230 actin gene sequences were derived from this study, among which 217 were from four closely related Pseudokeronopsis species and 13 from other hypotrichous ciliates. Our investigation shows that: (1) At least three duplication events occurred in ciliates: diversification of three actin genes (Actin I, II, III) happened after the divergence of ciliate classes but before that of subclasses. And several recent and genus-specific duplications were followed within Actin I (Sterkiella, Oxytricha, Uroleptus, etc.), Actin II (Sterkiella), respectively. (2) Within the genus Pseudokeronopsis, Actin I gene duplication events happened after P. carnea and P. erythrina diverged. In contrast, in the morphologically similar species P. flava and P. rubra, the duplication event preceded diversification of the two species. The Actin II gene duplication events preceded divergence of the genus Pseudokeronopsis. (3) Phylogenetic analyses revealed that actin is suitable for resolving ciliate classes, but may not be used to infer lower taxon relationships.

  4. A BRIEF HISTORY OF CILIATE STUDIES (LATE XVII THE FIRST THIRD OF THE XX CENTURY)

    OpenAIRE

    2004-01-01

    The most prominent protistologists who worked with ciliates from the Leeuwenhoek time up to the beginning of the XX century are mentioned. Their achievements in ciliatology and especially in taxonomy of ciliates are briefly discussed on the basis of the original literature and reviews, published during the last 150 years.

  5. Grazing on autotrophic and heterotrophic picoplankton by ciliates isolated from Lake Kinneret, Israel

    NARCIS (Netherlands)

    Hadas, O.; Malinsky-Rushansky, N.; Pinkas, R.; Cappenberg, T.E.

    1998-01-01

    The rates of ingestion of three ciliates (Colpoda steinii, Cyclidium sp. and Stylonichia sp.) on fluorescently labeled heterotrophic bacteria, picocyanobacteria (Synechococcus P, CN) and a picoeukaryote isolated from Lake Kinneret were measured. Uptake values were 930, 35 and 1210 bacteria ciliate (

  6. The mitochondrial genomes of the ciliates Euplotes minuta and Euplotes crassus.

    NARCIS (Netherlands)

    Graaf, R.M. de; Alen, T.A. van; Dutilh, B.E.; Kuiper, J.W.P.; Zoggel, H.J. van; Huynh, M.B.; Gortz, H.D.; Huynen, M.A.; Hackstein, J.H.P.

    2009-01-01

    BACKGROUND: There are thousands of very diverse ciliate species from which only a handful mitochondrial genomes have been studied so far. These genomes are rather similar because the ciliates analysed (Tetrahymena spp. and Paramecium aurelia) are closely related. Here we study the mitochondrial geno

  7. Tanycyte-Like Cells Form a Blood–Cerebrospinal Fluid Barrier in the Circumventricular Organs of the Mouse Brain

    OpenAIRE

    2013-01-01

    Tanycytes are highly specialized ependymal cells that form a blood–cerebrospinal fluid (CSF) barrier at the level of the median eminence (ME), a circumventricular organ (CVO) located in the tuberal region of the hypothalamus. This ependymal layer harbors well-organized tight junctions, a hallmark of central nervous system barriers that is lacking in the fenestrated portal vessels of the ME. The displacement of barrier properties from the vascular to the ventricular side allows the diffusion o...

  8. New Primers Targeting Full-Length Ciliate 18S rRNA Genes and Evaluation of Dietary Effect on Rumen Ciliate Diversity in Dairy Cows.

    Science.gov (United States)

    Zhang, Jun; Zhao, Shengguo; Zhang, Yangdong; Sun, Peng; Bu, Dengpan; Wang, Jiaqi

    2015-12-01

    Analysis of the full-length 18S rRNA gene sequences of rumen ciliates is more reliable for taxonomical classification and diversity assessment than the analysis of partial hypervariable regions only. The objective of this study was to develop new oligonucleotide primers targeting the full-length 18S rRNA genes of rumen ciliates, and to evaluate the effect of different sources of dietary fiber (corn stover or a mixture of alfalfa hay and corn silage) and protein (mixed rapeseed, cottonseed, and/or soybean meals) on rumen ciliate diversity in dairy cows. Primers were designed based on a total of 137 previously reported ciliate 18S rRNA gene sequences. The 3'-terminal sequences of the newly designed primers, P.1747r_2, P.324f, and P.1651r, demonstrated >99% base coverage. Primer pair D (P.324f and P.1747r_2) was selected for the cloning and sequencing of ciliate 18S rRNA genes because it produced a 1423-bp amplicon, and did not amply the sequences of other eukaryotic species, such as yeast. The optimal species-level cutoff value for distinguishing between the operational taxonomic units of different ciliate species was 0.015. The phylogenetic analysis of full-length ciliate 18S rRNA gene sequences showed that distinct ciliate profiles were induced by the different sources of dietary fiber and protein. Dasytricha and Entodinium were the predominant genera in the ruminal fluid of dairy cattle, and Dasytricha was significantly more abundant in cows fed with corn stover than in cows fed with alfalfa hay and corn silage.

  9. SHORT TIME DYNAMICS OF CILIATE ABUNDANCE IN THE BOHAI SEA (CHINA)

    Institute of Scientific and Technical Information of China (English)

    张武昌; 王荣

    2002-01-01

    The ciliate community in the Bohai Sea (China) was studied from23 September to 7 October 1998. A hurricane struck the study area between the two grid station investigations, which were six days apart. Six tintinnid species(Favella panamensis, Leptotintinnus nordqvisti, Tintinnopsis butschlii, T. karajacensis, T. Radix and Wangiella dicollaria) were identified. Total cililate abundance in the surface layer ranged from 20 to 770 ind/l. In the first grid investigation, Tintinnopsis karajacensis dominated in the warm, low salinity waters at the Huanghe River mouth. Aloricate ciliate sp.1 dominated in the cold, high salinity waters in the northwest of the study area and the Bohai Strait. In the second grid investigation, T. Karajacensis almost disappeared. The abundance of aloricate ciliate sp.1 decreased drastically. The aloricate ciliate sp.2 dominatedat the Bohai Strait. The change of ciliate abundance may be due to the disturbance of hurricane.``

  10. Ecological functions of ciliated protozoa in marine ecosystem:effects on accumulation of ambient ammonia

    Institute of Scientific and Technical Information of China (English)

    Xu Henglong; Song Weibo; Zhu Mingzhuang; Wang Mei; Ma Honggang; Hu Xiaozhong

    2005-01-01

    Effects of ciliated protozoa, Euplotes vannus and Uronema marinum, on accumulation of ammonia in marine waters are detected using experimental ecological method, in order to reveal the contributions and functions of ciliates to the marine ecosystem. During experiments, the concentrations of ammonia-N, and the densities of ciliates and bacteria are measured. The results reveal that ciliates can change the procedure of ammonia accumulation by their grazing activity, and maintain ambient ammonium at low levels through interrupting the stationary phase of bacteria population growth and enhancing their growth and metabolism. The present work confirms that ciliates, as bacteria-predators, play positive roles in maintaining and improving water quality in marine ecosystems, especially in intensive mariculture biotopes.

  11. Ciliated protozoa of two antarctic lakes: analysis by quantitative protargol staining and examination of artificial substrates

    Science.gov (United States)

    Kepner, R. L. Jr; Wharton, R. A. Jr; Coats, D. W.; Wharton RA, J. r. (Principal Investigator)

    1999-01-01

    Planktonic and artificial substrate-associated ciliates have been identified in two perennially ice-covered antarctic lakes of the McMurdo Dry Valleys. Abundances estimated by quantitative protargol staining ranged from Vorticella. The taxonomic findings compare favorably with those of previous investigators; however four previously unreported genera were observed in both Lakes Fryxell and Hoare. The variability in the depth distributions of ciliates in Lake Fryxell is explained in terms of lake physicochemical properties and ciliate prey distributions, while factors related to temporal succession in the Lake Hoare assemblage remain unexplained. Local marine or temperate zone freshwater habitats are a more likely source than the surrounding dry valleys soils for present ciliate colonists in these lakes. Although the taxonomic uncertainties require further examination, our results suggest that ciliate populations in these antarctic lakes undergo significant fluctuations and are more diverse than was previously recognized.

  12. Cross-study analysis of genomic data defines the ciliate multigenic epiplasmin family: strategies for functional analysis in Paramecium tetraurelia

    Directory of Open Access Journals (Sweden)

    Ravet Viviane

    2009-06-01

    Full Text Available Abstract Background The sub-membranous skeleton of the ciliate Paramecium, the epiplasm, is composed of hundreds of epiplasmic scales centered on basal bodies, and presents a complex set of proteins, epiplasmins, which belong to a multigenic family. The repeated duplications observed in the P. tetraurelia genome present an interesting model of the organization and evolution of a multigenic family within a single cell. Results To study this multigenic family, we used phylogenetic, structural, and analytical transcriptional approaches. The phylogenetic method defines 5 groups of epiplasmins in the multigenic family. A refined analysis by Hydrophobic Cluster Analysis (HCA identifies structural characteristics of 51 epiplasmins, defining five separate groups, and three classes. Depending on the sequential arrangement of their structural domains, the epiplasmins are defined as symmetric, asymmetric or atypical. The EST data aid in this classification, in the identification of putative regulating sequences such as TATA or CAAT boxes. When specific RNAi experiments were conducted using sequences from either symmetric or asymmetric classes, phenotypes were drastic. Local effects show either disrupted or ill-shaped epiplasmic scales. In either case, this results in aborted cell division. Using structural features, we show that 4 epiplasmins are also present in another ciliate, Tetrahymena thermophila. Their affiliation with the distinctive structural groups of Paramecium epiplasmins demonstrates an interspecific multigenic family. Conclusion The epiplasmin multigenic family illustrates the history of genomic duplication in Paramecium. This study provides a framework which can guide functional analysis of epiplasmins, the major components of the membrane skeleton in ciliates. We show that this set of proteins handles an important developmental information in Paramecium since maintenance of epiplasm organization is crucial for cell morphogenesis.

  13. A mesocosm study of the changes in marine flagellate and ciliate communities in a crude oil bioremediation trial.

    Science.gov (United States)

    Gertler, Christoph; Näther, Daniela J; Gerdts, Gunnar; Malpass, Mark C; Golyshin, Peter N

    2010-07-01

    Protozoan grazers play an important role in controlling the density of crude-oil degrading marine communities as has been evidenced in a number of microcosm experiments. However, small bioreactors contain a low initial titre of protozoa and the growth of hydrocarbon-depleting bacteria is accompanied by the fast depletion of mineral nutrients and oxygen, which makes microcosms rather unsuitable for simulating the sequence of events after the oil spill in natural seawater environment. In the present study, the population dynamics of marine protozoan community have been analysed in a 500 l mesocosm experiment involving bioaugmented oil booms that contained oil sorbents and slow-release fertilisers. A significant increase in numbers of marine flagellates and ciliates on biofilms of oil-degrading microbes was microscopically observed as early as 8 days after the start of the experiment, when protozoa exhibited a population density peak making up to 3,000 cells ml(-1). Further, the protozoan density varied throughout the experiment, but never dropped below 80 cells ml(-1). An 18S rRNA gene-based fingerprinting analysis revealed several changes within the eukaryotic community over the whole course of the experiment. Initial growth of flagellates and small ciliates was followed by a predominance of larger protozoa. According to microscopic observations and SSU rRNA molecular analyses, most predominant were the ciliates belonging to Euplotidae and Scuticociliatia. This is the first study to characterise the eukaryotic communities specifically in a large-scale oil bioremediation trial using both microscopy-based and several molecular techniques.

  14. Diverse modes of reproduction in the marine free-living ciliate Glauconema trihymene

    Directory of Open Access Journals (Sweden)

    Zufall Rebecca A

    2010-04-01

    Full Text Available Abstract Background Most free-living ciliates reproduce by equal fission or budding during vegetative growth. In certain ciliates, reproduction occurs inside the cyst wall, viz. reproductive cysts, but more complex reproductive strategies have generally been thought to be confined to parasitic or symbiotic species, e.g. Radiophrya spp. Results In addition to equal fission, asymmetric binary division and reproductive cysts were discovered in the free-living bacterivorous scuticociliate Glauconema trihymene Thompson, 1966. Asymmetric division is an innate physiological state that can be induced by sufficient food, and the higher the food concentration, the longer the asymmetric division persists. During asymmetric division, nuclear and somatic structures divide with transiently arrested cytokinesis and variable positioning of macronuclei. Phylogenetic analysis, based on the small subunit of ribosomal DNA (SSU rDNA sequences, showed that the G. trihymene isolate studied here nests with typical scuticociliates and is paraphyletic to both the symbiotic apostome and astome ciliates, some of which also produce progeny by asymmetric division. Conclusions The asymmetric division in G. trihymene has no precedent among undisturbed free-living ciliates. The coexistence of multiple modes of reproduction may represent a previously undescribed reproductive strategy for ciliates living on food patches in coastal waters. This may also be indicative of similar reproductive strategies among other polyphenic ciliates, which have not been intensively studied. Asymmetric division provides a special opportunity for studying ciliates' phenotypic plasticity and may also illuminate the origins of multicellularity.

  15. Climate scaling behaviour in the dynamics of the marine interstitial ciliate community

    Science.gov (United States)

    Varotsos, Costas A.; Mazei, Yuri A.; Burkovsky, Igor; Efstathiou, Maria N.; Tzanis, Chris G.

    2016-08-01

    The present paper uses characteristics of the marine interstitial ciliate community in the White Sea intertidal sandflat during the period of 1991-2011, in order to study its long-term dynamics, investigating in particular whether it exhibits scaling behaviour into its fluctuations, which is a characteristic feature of the climate system. To this aim, a recently proposed version of the detrended fluctuation analysis is herewith employed which has been successfully applied to a wide range of simulated and physiologic time series in recent years. In case that the fluctuations of the ciliate community present self-similarity processes, an ideal field test for the currently proposed biological models will be established, allowing to evaluate their reliability. Indeed, we show for the first time that different ciliate species exhibit long-range power-law persistent correlations. This means that ciliate fluctuations in different intervals are positively correlated, obeying a power-law behaviour. Although the origin of power-law temporal evolution of ciliates should be further investigated, this finding is probably associated with the self-organized criticality of ciliates. It should be noted that the long-range correlations obtained do not imply the presence of specific cycles but rather the existence of dynamic links between long-term and short-term temporal evolution. The scaling behaviour found in marine interstitial ciliate community should be taken into account in the investigation of their response to the present or future climate change.

  16. Effect of salt and urban water samples on bacterivory by the ciliate, Tetrahymena thermophila

    Energy Technology Data Exchange (ETDEWEB)

    St Denis, C.H.; Pinheiro, M.D.O.; Power, M.E. [Department of Biology, University of Waterloo, 200 University Ave. W, Waterloo, Ontario N2L 3G1 (Canada); Bols, Niels C., E-mail: ncbols@uwaterloo.c [Department of Biology, University of Waterloo, 200 University Ave. W, Waterloo, Ontario N2L 3G1 (Canada)

    2010-02-15

    The effect of road salt on the eating of bacteria or bacterivory by the ciliate, Tetrahymena thermophila, was followed in non-nutrient Osterhout's solution with Escherichia coli expressing green fluorescent protein. Bacterivory was impaired at between 0.025 and 0.050% w/v but the ciliates appeared to have normal morphologies and motilities, whereas at above 0.1%, bacterivory was blocked and many ciliates died. By contrast, E. coli remained viable, suggesting salt could alter predator-prey relationships in microbial communities. In nutrient medium, salt was not toxic and the ciliates grew. After growth in salt, ciliates consumed bacteria in 0.2% salt, indicating the salt acclimation of bacterivory. Bacteria and ciliates were added to urban creek samples to compare their capacity to support exogenous bacterivory. Even though samples were collected weekly for a year and be expected to have fluctuating salt levels as a result of deicing, all creek samples supported a similar level of bacterivory. - Road salt at some concentrations inhibits bacterivory by ciliates, and thus potentially could alter the microbial food web.

  17. First report of ciliate (Protozoa) epibionts on deep-sea harpacticoid copepods

    Science.gov (United States)

    Sedlacek, Linda; Thistle, David; Fernandez-Leborans, Gregorio; Carman, Kevin R.; Barry, James P.

    2013-08-01

    We report the first observations of ciliate epibionts on deep-sea, benthic harpacticoid copepods. One ciliate epibiont species belonged to class Karyorelictea, one to subclass Suctoria, and one to subclass Peritrichia. Our samples came from the continental rise off central California (36.709°N, 123.523°W, 3607 m depth). We found that adult harpacticoids carried ciliate epibionts significantly more frequently than did subadult copepodids. The reason for the pattern is unknown, but it may involve differences between adults and subadult copepodids in size or in time spent swimming. We also found that the ciliate epibiont species occurred unusually frequently on the adults of two species of harpacticoid copepod; a third harpacticoid species just failed the significance test. When we ranked the 57 harpacticoid species in our samples in order of abundance, three species identified were, as a group, significantly more abundant than expected by chance if one assumes that the abundance of the group and the presence of ciliate epibionts on them were uncorrelated. High abundance may be among the reasons a harpacticoid species carries a ciliate epibiont species disproportionately frequently. For the combinations of harpacticoid species and ciliate epibiont species identified, we found one in which males and females differed significantly in the proportion that carried epibionts. Such a sex bias has also been reported for shallow-water, calanoid copepods.

  18. Genesis of amorphous calcium carbonate containing alveolar plates in the ciliate Coleps hirtus (Ciliophora, Prostomatea).

    Science.gov (United States)

    Lemloh, Marie-Louise; Marin, Frédéric; Herbst, Frédéric; Plasseraud, Laurent; Schweikert, Michael; Baier, Johannes; Bill, Joachim; Brümmer, Franz

    2013-02-01

    In the protist world, the ciliate Coleps hirtus (phylum Ciliophora, class Prostomatea) synthesizes a peculiar biomineralized test made of alveolar plates, structures located within alveolar vesicles at the cell cortex. Alveolar plates are arranged by overlapping like an armor and they are thought to protect and/or stiffen the cell. Although their morphology is species-specific and of complex architecture, so far almost nothing is known about their genesis, their structure and their elemental and mineral composition. We investigated the genesis of new alveolar plates after cell division and examined cells and isolated alveolar plates by electron microscopy, energy-dispersive X-ray spectroscopy, FTIR and X-ray diffraction. Our investigations revealed an organic mesh-like structure that guides the formation of new alveolar plates like a template and the role of vesicles transporting inorganic material. We further demonstrated that the inorganic part of the alveolar plates is composed out of amorphous calcium carbonate. For stabilization of the amorphous phase, the alveolar vesicles, the organic fraction and the element phosphorus may play a role.

  19. Ciliated hepatic foregut cyst: report of first case in China and review of literature

    Institute of Scientific and Technical Information of China (English)

    蔡秀军; 黄迪宇; 梁霄; 虞洪; 李伟; 王先法; 彭淑牖

    2004-01-01

    Objective: To report the first case of ciliated hepatic foregut cyst in China, and review of literature to introduce the characteristics of this disease for doctors to recognize this disease.Method: Report the clinical procedure of diagnosis and treatment for the first case of ciliated hepatic foregut cyst in China, and to review the embryologic genesis, incidence,clinical manifestation, radiologic features and therapeutic principle of this disease. Results: We performed the resection for ciliated hepatic foregut cyst under laparoscopy; the patient recovered well after the procedure. Conclusion: Ciliated hepatic foregut cyst is quite rare clinically, belongs to non-parasitic,solitary and unilocular cystic lesion, is always less than 4cm in diameter, mostly seen in the left lobe, and has the tendency of malignant change. It should be removed as soon as diagnosed.

  20. New records of epibiont Ciliates (Ciliophora) from Indian coast with descriptions of six new species

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterjee, T.; Fernandez-Leborans, G.; Ramteke, D.; Ingole, B

    Six epibiont ciliates Cothurnia palkensis, C. nova, C. disper, C. dovgali, C. mannaerensis and C. clampi are described as new for science from the Indian coast. Acineta truncata Collin, 1909 and A. tuberosa Ehrenberg, 1834 are reported here...

  1. Benthic ciliate and meiofaunal communities in two contrasting habitats of an intertidal estuarine wetland

    Science.gov (United States)

    Du, Yongfen; Xu, Kuidong; Warren, Alan; Lei, Yanli; Dai, Renhai

    2012-05-01

    Annual variations in benthic meiofaunal and ciliated protozoan communities were investigated using monthly samplings from June 2006 to May 2007 in two habitats characterized by different vegetal coverage in an estuarine intertidal wetland of Qingdao Jiaozhou Bay, China. The sediment composition was stable at each site: sediments densely covered with seagrass (Suaeda glauca) in the lower estuarine site (Station S) were finer, with higher content of organic matter, phaeopigments and water than sediments at the upper estuarine site (Station S-P) which was unvegetated other than for patches of S. glauca and common reed (Phragmites australis). Chlorophyll a exhibited a similar distribution in the two habitats. A total of 14 meiofaunal groups, and 249 species of ciliates belonging to 37 genera, 28 families and 16 orders, were isolated from the two sites. Univariate and multivariate measures of the communities were significantly different between the two habitats. There were higher abundances of ciliates and meiofauna, and a greater diversity of ciliates, at Station S than Station S-P (223 vs. 61 species). Herbivorous ciliates were numerically predominant in ciliate communities at both sites. The representative ciliates at Station S-P belonged to the Cyrtophorida and appeared to be a reduced subset of the assemblage at Station S, which was characterized by members of the Prostomatida, Cyrtophorida, Hypotrichida and Scuticociliatida. More than 96% of the total meiofauna were nematodes, accounting for 93% of the differences in the abundance compositions of the meiofaunal communities between habitats. The average individual weights of nematodes were nearly 3 times greater at Station S than Station S-P, indicating a distinctive species composition at each site. Temperature, salinity and food availability were key factors that regulated the ciliate and meiofaunal community structure. Nematodes were the dominant group in terms of the combined abundance, biomass and benthic

  2. Akhirin regulates the proliferation and differentiation of neural stem cells in intact and injured mouse spinal cord.

    Science.gov (United States)

    Abdulhaleem, Felemban Athary M; Song, Xiaohong; Kawano, Rie; Uezono, Naohiro; Ito, Ayako; Ahmed, Giasuddin; Hossain, Mahmud; Nakashima, Kinichi; Tanaka, Hideaki; Ohta, Kunimasa

    2015-05-01

    Although the central nervous system is considered a comparatively static tissue with limited cell turnover, cells with stem cell properties have been isolated from most neural tissues. The spinal cord ependymal cells show neural stem cell potential in vitro and in vivo in injured spinal cord. However, very little is known regarding the ependymal niche in the mouse spinal cord. We previously reported that a secreted factor, chick Akhirin, is expressed in the ciliary marginal zone of the eye, where it works as a heterophilic cell-adhesion molecule. Here, we describe a new crucial function for mouse Akhirin (M-AKH) in regulating the proliferation and differentiation of progenitors in the mouse spinal cord. During embryonic spinal cord development, M-AKH is transiently expressed in the central canal ependymal cells, which possess latent neural stem cell properties. Targeted inactivation of the AKH gene in mice causes a reduction in the size of the spinal cord and decreases BrdU incorporation in the spinal cord. Remarkably, the expression patterns of ependymal niche molecules in AKH knockout (AKH-/-) mice are different from those of AKH+/+, both in vitro and in vivo. Furthermore, we provide evidence that AKH expression in the central canal is rapidly upregulated in the injured spinal cord. Taken together, these results indicate that M-AKH plays a crucial role in mouse spinal cord formation by regulating the ependymal niche in the central canal.

  3. Macronuclear genome sequence of the ciliate Tetrahymena thermophila, a model eukaryote.

    Directory of Open Access Journals (Sweden)

    Jonathan A Eisen

    2006-09-01

    Full Text Available The ciliate Tetrahymena thermophila is a model organism for molecular and cellular biology. Like other ciliates, this species has separate germline and soma functions that are embodied by distinct nuclei within a single cell. The germline-like micronucleus (MIC has its genome held in reserve for sexual reproduction. The soma-like macronucleus (MAC, which possesses a genome processed from that of the MIC, is the center of gene expression and does not directly contribute DNA to sexual progeny. We report here the shotgun sequencing, assembly, and analysis of the MAC genome of T. thermophila, which is approximately 104 Mb in length and composed of approximately 225 chromosomes. Overall, the gene set is robust, with more than 27,000 predicted protein-coding genes, 15,000 of which have strong matches to genes in other organisms. The functional diversity encoded by these genes is substantial and reflects the complexity of processes required for a free-living, predatory, single-celled organism. This is highlighted by the abundance of lineage-specific duplications of genes with predicted roles in sensing and responding to environmental conditions (e.g., kinases, using diverse resources (e.g., proteases and transporters, and generating structural complexity (e.g., kinesins and dyneins. In contrast to the other lineages of alveolates (apicomplexans and dinoflagellates, no compelling evidence could be found for plastid-derived genes in the genome. UGA, the only T. thermophila stop codon, is used in some genes to encode selenocysteine, thus making this organism the first known with the potential to translate all 64 codons in nuclear genes into amino acids. We present genomic evidence supporting the hypothesis that the excision of DNA from the MIC to generate the MAC specifically targets foreign DNA as a form of genome self-defense. The combination of the genome sequence, the functional diversity encoded therein, and the presence of some pathways missing from

  4. Space station image captures a red tide ciliate bloom at high spectral and spatial resolution.

    Science.gov (United States)

    Dierssen, Heidi; McManus, George B; Chlus, Adam; Qiu, Dajun; Gao, Bo-Cai; Lin, Senjie

    2015-12-01

    Mesodinium rubrum is a globally distributed nontoxic ciliate that is known to produce intense red-colored blooms using enslaved chloroplasts from its algal prey. Although frequent enough to have been observed by Darwin, blooms of M. rubrum are notoriously difficult to quantify because M. rubrum can aggregate into massive clouds of rusty-red water in a very short time due to its high growth rates and rapid swimming behavior and can disaggregate just as quickly by vertical or horizontal dispersion. A September 2012 hyperspectral image from the Hyperspectral Imager for the Coastal Ocean sensor aboard the International Space Station captured a dense red tide of M. rubrum (10(6) cells per liter) in surface waters of western Long Island Sound. Genetic data confirmed the identity of the chloroplast as a cryptophyte that was actively photosynthesizing. Microscopy indicated extremely high abundance of its yellow fluorescing signature pigment phycoerythrin. Spectral absorption and fluorescence features were related to ancillary photosynthetic pigments unique to this organism that cannot be observed with traditional satellites. Cell abundance was estimated at a resolution of 100 m using an algorithm based on the distinctive yellow fluorescence of phycoerythrin. Future development of hyperspectral satellites will allow for better enumeration of bloom-forming coastal plankton, the associated physical mechanisms, and contributions to marine productivity.

  5. Ciliate Paramecium is a natural reservoir of Legionella pneumophila

    Science.gov (United States)

    Watanabe, Kenta; Nakao, Ryo; Fujishima, Masahiro; Tachibana, Masato; Shimizu, Takashi; Watarai, Masahisa

    2016-04-01

    Legionella pneumophila, the causative agent of Legionnaires’ disease, replicates within alveolar macrophages and free-living amoebae. However, the lifestyle of L. pneumophila in the environment remains largely unknown. Here we established a novel natural host model of L. pneumophila endosymbiosis using the ciliate Paramecium caudatum. We also identified Legionella endosymbiosis-modulating factor A (LefA), which contributes to the change in life stage from endosymbiosis to host lysis, enabling escape to the environment. We isolated L. pneumophila strains from the environment, and they exhibited cytotoxicity toward P. caudatum and induced host lysis. Acidification of the Legionella-containing vacuole (LCV) was inhibited, and enlarged LCVs including numerous bacteria were observed in P. caudatum infected with L. pneumophila. An isogenic L. pneumophila lefA mutant exhibited decreased cytotoxicity toward P. caudatum and impaired the modification of LCVs, resulting in the establishment of endosymbiosis between them. Our results suggest that L. pneumophila may have a mechanism to switch their endosymbiosis in protistan hosts in the environment.

  6. Ciliate Paramecium is a natural reservoir of Legionella pneumophila

    Science.gov (United States)

    Watanabe, Kenta; Nakao, Ryo; Fujishima, Masahiro; Tachibana, Masato; Shimizu, Takashi; Watarai, Masahisa

    2016-01-01

    Legionella pneumophila, the causative agent of Legionnaires’ disease, replicates within alveolar macrophages and free-living amoebae. However, the lifestyle of L. pneumophila in the environment remains largely unknown. Here we established a novel natural host model of L. pneumophila endosymbiosis using the ciliate Paramecium caudatum. We also identified Legionella endosymbiosis-modulating factor A (LefA), which contributes to the change in life stage from endosymbiosis to host lysis, enabling escape to the environment. We isolated L. pneumophila strains from the environment, and they exhibited cytotoxicity toward P. caudatum and induced host lysis. Acidification of the Legionella-containing vacuole (LCV) was inhibited, and enlarged LCVs including numerous bacteria were observed in P. caudatum infected with L. pneumophila. An isogenic L. pneumophila lefA mutant exhibited decreased cytotoxicity toward P. caudatum and impaired the modification of LCVs, resulting in the establishment of endosymbiosis between them. Our results suggest that L. pneumophila may have a mechanism to switch their endosymbiosis in protistan hosts in the environment. PMID:27079173

  7. Application of nested PCR-DGGE (denaturing gradient gel electrophoresis) for the analysis of ciliate communities in soils.

    Science.gov (United States)

    Shimano, Satoshi; Sambe, Mitsuo; Kasahara, Yasuhiro

    2012-01-01

    Ciliates play important roles as prey and predators in ecosystems. Changes in the ciliate community can affect the composition and population of microfauna and microflora in ecosystems. To investigate the structure of ciliate communities, we developed a nested PCR-DGGE method, which combines a universal eukaryotic-specific primer set in the first PCR step with a ciliate-specific primer set in the second PCR step, to amplify 18S rRNA genes from ciliates. The 300 bp DGGE fragments generated more bands on the gel than the 600 bp DGGE fragments. Prior to bead beating, DNA extraction of ciliates from soil samples was optimized with a combination of freeze-thaw cycles and ultrasonication. We applied this nested PCR-DGGE method to agricultural soils amended with 0, 120, 300, and 600 t ha⁻¹ year⁻¹ of livestock slurry. The results from the DGGE profiles and principal component analysis (PCA) revealed that the supplement of slurry to soils influenced the ciliate communities. From phylogenetic analysis, 108 DGGE bands were assigned to six classes, which included Spirotrichea and Colpodea, of the subphylum Intramacronucleata, and one class of the subphylum Postciliodesmatophora. These results indicated that a wide variety of taxonomic groups were detected by DGGE profiling. Thus, the nested PCR-DGGE method described here could clearly differentiate between ciliate communities within soil samples and allowed for the phylogenetic identification of these ciliates at the class level.

  8. First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species.

    Science.gov (United States)

    Siqueira-Castro, Isabel Cristina Vidal; Greinert-Goulart, Juliane Araújo; Bonatti, Tais Rondello; Yamashiro, Sandra; Franco, Regina Maura Bueno

    2016-06-01

    Ciliated protozoa are important components of the microbial food web in various habitats, especially aquatic environments. These organisms are useful bioindicators for both environmental quality assessment and the wastewater purification process. The pathogenic parasitic protozoan species Giardia and Cryptosporidium represent a significant concern for human health, being responsible for numerous disease outbreaks worldwide. The predation of cysts and oocysts in 15 ciliate species from water and sewage samples collected in Campinas, São Paulo, Brazil were verified under laboratory conditions. The ciliated protozoan species were selected based on their mode of nutrition, and only bacterivorous and suspension-feeders were considered for the experiments. The species Blepharisma sinuosum, Euplotes aediculatus, Sterkiella cavicola, Oxytricha granulifera, Vorticella infusionum, Spirostomum minus, and Stentor coeruleus ingested cysts and oocysts, the resistance forms of Giardia spp. and Cryptosporidium spp., respectively. This is the first time that the ingestion of Giardia cysts by ciliated protozoa has been reported. These findings may contribute to a better understanding of the biological removal of these pathogens from aquatic environments.

  9. On classical and quantum error-correction in ciliate mate selection.

    Science.gov (United States)

    Clark, Kevin B

    2010-07-01

    Ciliated protozoa sensing pheromones secreted from nonself mating types engage in preconjugal "courtship" dances and contacts. Using simulated "social" trials, I recently showed the heterotrich ciliate, Spirostomum ambiguum, can learn to advertise degrees of mating fitness to "suitors" and "rivals" when serially contracting or (ciliary) reversing at variable rates. Conspicuous consumers signal higher quality reproductive status by playing "harder-to-get" via metabolically wasteful avoidance displays that hinder the exchange of preconjugal touches between "courting" couples. Conversely, prudent savers conserve energy pending situations more favorable for conjugating a partner. These ciliates reply with lower avoidance frequencies, guaranteeing nearby conspecifics of being "easier-to-get". By deciding to switch from behavioral strategies signaling conspicuous consumption to those signaling prudent savings, fitter ciliates learn to altruistically sacrifice net payoffs and persuade suitors to participate in paired reproduction. Less fit ciliates, unable to sustain long periods of high response rates, switch their behavioral strategies of prudent savings to briefly emit conspicuous consumption and thus learn to opportunistically cheat superior rivals. Mating competency depends, in part, on the efficiency of heuristics formed from recursive strategy searches and use. Heuristics represent stored patterns of action which evolve into ordered computational networks supporting entire courting repertoires. As ciliates expand signaling skills over many trials, the connectivity between strategies strengthens from Hebbian-like learning, leading to faster decisions about the appropriateness of courting messages and replies. The best experts master signaling decisions at efficiencies comparable to finding target solutions from superposed states with Grover's quantum search algorithm. I here append these findings with a critique on the feasibility of serial behavioral strategies to

  10. The mitochondrial genomes of the ciliates Euplotes minuta and Euplotes crassus

    Directory of Open Access Journals (Sweden)

    Huynh Minh

    2009-11-01

    Full Text Available Abstract Background There are thousands of very diverse ciliate species from which only a handful mitochondrial genomes have been studied so far. These genomes are rather similar because the ciliates analysed (Tetrahymena spp. and Paramecium aurelia are closely related. Here we study the mitochondrial genomes of the hypotrichous ciliates Euplotes minuta and Euplotes crassus. These ciliates are only distantly related to Tetrahymena spp. and Paramecium aurelia, but more closely related to Nyctotherus ovalis, which possesses a hydrogenosomal (mitochondrial genome. Results The linear mitochondrial genomes of the hypotrichous ciliates Euplotes minuta and Euplotes crassus were sequenced and compared with the mitochondrial genomes of several Tetrahymena species, Paramecium aurelia and the partially sequenced mitochondrial genome of the anaerobic ciliate Nyctotherus ovalis. This study reports new features such as long 5'gene extensions of several mitochondrial genes, extremely long cox1 and cox2 open reading frames and a large repeat in the middle of the linear mitochondrial genome. The repeat separates the open reading frames into two blocks, each having a single direction of transcription, from the repeat towards the ends of the chromosome. Although the Euplotes mitochondrial gene content is almost identical to that of Paramecium and Tetrahymena, the order of the genes is completely different. In contrast, the 33273 bp (excluding the repeat region piece of the mitochondrial genome that has been sequenced in both Euplotes species exhibits no difference in gene order. Unexpectedly, many of the mitochondrial genes of E. minuta encoding ribosomal proteins possess N-terminal extensions that are similar to mitochondrial targeting signals. Conclusion The mitochondrial genomes of the hypotrichous ciliates Euplotes minuta and Euplotes crassus are rather different from the previously studied genomes. Many genes are extended in size compared to mitochondrial

  11. Natural products from aquatic eukaryotic microorganisms for cancer therapy: Perspectives on anti-tumour properties of ciliate bioactive molecules.

    Science.gov (United States)

    Catalani, Elisabetta; Proietti Serafini, Francesca; Zecchini, Silvia; Picchietti, Simona; Fausto, Anna Maria; Marcantoni, Enrico; Buonanno, Federico; Ortenzi, Claudio; Perrotta, Cristiana; Cervia, Davide

    2016-11-01

    Several modern drugs, including those for cancer therapy, have been isolated from natural sources, are based on natural products and its derivatives, or mime natural products. Some of them are in clinical use, others in clinical trials. The success of natural products in drug discovery is related to their biochemical characteristics and to the technologic methods used to study their feature. Natural compounds may acts as chemo-preventive agents and as factors that increase therapeutic efficacy of existing drugs, thus overcoming cancer cell drug resistance that is the main factor determining the failure in conventional chemotherapy. Water environment, because of its physical and chemical conditions, shows an extraordinary collection of natural biological substances with an extensive structural and functional diversity. The isolation of bioactive molecules has been reported from a great variety of aquatic organisms; however, the therapeutic application of molecules from eukaryotic microorganisms remains inadequately investigated and underexploited on a systematic basis. Herein we describe the biological activities in mammalian cells of selected substances isolated from ciliates, free-living protozoa common almost everywhere there is water, focusing on their anti-tumour actions and their possible therapeutic activity. In particular, we unveil the cellular and molecular machine mediating the effects of cell type-specific signalling protein pheromone Er-1 and secondary metabolites, i.e. euplotin C and climacostol, in cancer cells. To support the feasibility of climacostol-based approaches, we also present novel findings and report additional mechanisms of action using both in vitro and in vivo models of mouse melanomas, with the scope of highlighting new frontiers that can be explored also in a therapeutic perspective. The high skeletal chemical difference of ciliate compounds, their sustainability and availability, also through the use of new organic synthesis

  12. Geometric control of ciliated band regulatory states in the sea urchin embryo.

    Science.gov (United States)

    Barsi, Julius C; Li, Enhu; Davidson, Eric H

    2015-03-01

    The trapezoidal ciliated band (CB) of the postgastrular sea urchin embryo surrounds the oral ectoderm, separating it from adjacent embryonic territories. Once differentiated, the CB is composed of densely arranged cells bearing long cilia that endow the larva with locomotion and feeding capability. The spatial pattern from which the CB will arise is first evidenced during pregastrular stages by expression of the pioneer gene onecut. Immediately after gastrulation, the CB consists of four separate regulatory state domains, each of which expresses a unique set of transcription factors: (1) the oral apical CB, located within the apical neurogenic field; (2) the animal lateral CB, which bilaterally separates the oral from aboral ectoderm; (3) the vegetal lateral CB, which bilaterally serves as signaling centers; and (4) the vegetal oral CB, which delineates the boundary with the underlying endoderm. Remarkably, almost all of the regulatory genes specifically expressed within these domains are downregulated by interference with SoxB1 expression, implying their common activation by this factor. Here, we show how the boundaries of the CB subdomains are established, and thus ascertain the design principle by which the geometry of this unique and complex regulatory state pattern is genomically controlled. Each of these boundaries, on either side of the CB, is defined by spatially confined transcriptional repressors, the products of regulatory genes operating across the border of each subdomain. In total this requires deployment of about ten different repressors, which we identify in this work, thus exemplifying the complexity of information required for spatial regulatory organization during embryogenesis.

  13. Biochemical and immunological characterization of the microfibrillar ecto-endoplasmic boundary in the ciliate Isotricha prostoma.

    Science.gov (United States)

    Vigues, B; Metenier, G; Groliere, C A

    1984-01-01

    The cytoplasm of the ciliated protozoan Isotricha prostoma is compartmented by a continuous fibrillar system made up of a double layer of 4 nm-diameter filaments: the microfibrillar ecto-endoplasmic boundary (EEB). Isolation of this structure after treatment of the cells in a buffer of low ionic strength in the presence of the detergent Triton X-100 evidenced connections linking the two filamentous layers. One dimensional electrophoresis on SDS-polyacrylamide gel of EEB fractions revealed several major proteins with apparent molecular weights between 11 and 23 K. Of these, two neighboring bands of MW22 and 23 K were removed from gels and used as antigens to obtain rabbit antibodies. The antiserum obtained reacted specifically with injected proteins as shown by the technique of immunological detection on nitrocellulose sheets using the peroxidase reaction product. Electron microscopy localization of the antigens with anti-IgG coupled with colloidal gold showed significant labeling of the EEB within the cortex of Isotricha permeabilized with Triton X-100. We hope that the 22-23 K antiserum will prove to be a useful tool for the comparative study of other non-actin filament systems in Protozoa.

  14. Distribution of a centrosomal antigen during morphogenesis in the ciliated protozoan Euplotes.

    Science.gov (United States)

    Fleury, A; Lemullois, M; Coffe, G

    1998-07-01

    Ciliates assemble basal bodies in great number at many stages of the life-cycle. In order to understand their assembly mechanisms, we screened a library of monoclonal antibodies directed against pericentriolar material. One of these antibodies, CTR210, was used previously to follow steps of this assembly process: in Paraurostyla, new basal bodies appear along a scaffold of linear structures recognized by this antibody. The very unusual behavior of this antigen deserved confirmation in other species. In the present study, we show by immunofluorescence that, in another phylogenetically very distant species, Euplotes, basal bodies are assembled in the same pathway during division. In addition, this antibody recognizes a filamentous ring located at the division furrow and linking many basal body assemblages. By cell fractionation and cytoskeletal extraction, we obtained fractions enriched in basal bodies and associated material. Such fractions still display a high complexity in protein composition. These fractions were used to characterize the main target of the antibody as a doublet of 45 kDa. These results confirm previous results in terms of functionality of the protein recognized by the antibody, but raise new questions in terms of the assignment of the recognized protein to the HSP70 family as hypothesized previously.

  15. Philasterides dicentrarchi, a histophagous ciliate causing scuticociliatosis in olive flounder, Philasterides dicentrarchi--histopathology investigations.

    Science.gov (United States)

    Harikrishnan, Ramasamy; Jin, Chang-Nam; Kim, Ju-Sang; Balasundaram, Chellam; Heo, Moon-Soo

    2012-03-01

    Philasterides dicentrarchi is a histophagous scuticociliate infecting Korean olive flounder farms in Jeju Island, South Korea, where it causes significant economic losses. However, the route of entry of these parasites in olive flounder is currently unknown. In the present study, we attempted experimental infection with different doses (concentrations) of P. dicentrarchi by intraperitoneal (IP) injection; maximum cumulative mortality of 95% was recorded on the administration of 2.1×10(8) ciliates/ml. In small size group (3 cm length, 24±2 gwt) the ciliates were found in connective tissues of muscle, fins, and nervous tissue while in large size group (5 cm length, 47±3 gwt), the ciliates were predominantly occurred with associated symptoms of liquefaction in the central nervous system. The major clinico-pathological manifestations were loss of scales, appearance of bleached spots that coalesced to form brownish patches, hemorrhagic, and severe dermal necrotic lesion. In addition there was degeneration of muscle fibers, necrosis of the hepatic parenchyma, and severe edema of the intestinal walls, extensive fouling, necrotic degeneration and hyperplasia in the gill bronchial epithelium. In this study, many ciliates were found in the blood vessel, brain, dorsal fins, muscle, kidney, and vertebra of infected flounder. The histopathological investigations are of significant importance in view of possible routes of entry into the host and doses of ciliates that trigger fast infection for potential utility of drugs as a strategy for the control of P. dicentrarchi in farmed olive flounder.

  16. Involvement of Crawling and Attached Ciliates in the Aggregation of Particles in Wastewater Treatment Plants

    Directory of Open Access Journals (Sweden)

    Lucía Arregui

    2008-01-01

    Full Text Available The biological community in activated sludge wastewater plants is organized within this ecosystem as bioaggregates or flocs, in which the biotic component is embedded in a complex matrix comprised of extracellular polymeric substances mainly of microbial origin. The aim of this work is to study the role of different floc-associated ciliates commonly reported in wastewater treatment plants-crawling Euplotes and sessile Vorticella- in the formation of aggregates. Flocs, in experiments with ciliates and latex beads, showed more compactation and cohesion among particles than those in the absence of ciliates. Ciliates have been shown to contribute to floc formation through different mechanisms such as the active secretion of polymeric substances (extrusomes, their biological activities (movement and feeding strategies, or the cysts formation capacity of some species. Staining with lectins coupled to fluorescein showed that carbohydrate of the matrix contained glucose, manose, N-acetyl-glucosamine and galactose. Protein fraction revealed over the latex beads surfaces could probably be of bacterial origin, but nucleic acids represented an important fraction of the extracellular polymeric substances of ciliate origin.

  17. [Comparison of ciliate diversity in biodisc reactors which purify industrial wastewater].

    Science.gov (United States)

    Luna-Pabello, V M; Durán De Bazúa, C; Aladro-Lubel, M A

    1995-01-01

    The comparative study of the ciliate populations present in rotating biological reactors (biodiscs reactors) of 20 l working volume, treating three different wastewaters is the aim of this project. Wastewaters chosen were those of a maize mill, of a sugarcane/ethyl alcohol plant, and of a recycled paper mill. Its dissolved organic contents, measured as soluble chemical oxygen demand (COD) and five-day biochemical oxygen demand (BOD5), were 2040 mg COD/l and 585 mg BOD5/l for maize mill effluents (nejayote), 2000 mg COD/l and 640 mg BOD5/l for sugarcane/ethanol effluents (vinasses), and 960 mg COD/l and 120 mg BOD5/l for whitewaters of the paper industry. Results obtained indicate that ciliate proliferate in all chambers of reactors treating these wastewaters. The ciliates were more abundant in vinasses, followed by nejayote, and then whitewaters. Among protozoa, ciliates were present as follows: 19 species in total. Three of them were common for the three systems. Free swimming ciliates were in higher proportion than pedunculated ones. Its diversity was higher for the whitewaters system, next for nejayote, and the lesser, for vinasses, corroborating the fact that less polluted waters have higher organisms' diversity.

  18. Taxonomic Studies on a New Marine Ciliate, Apocoleps magnus gen. nov., spec. nov. (Ciliophora, Colepidae),Isolated from Qingdao, China

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiangrui; Alan Warren; SONG Weibo

    2009-01-01

    The morphology and infraciliature of a new marine colepid ciliate, Apocoleps magnus gen. nov., spee. nov., are described based on living observations and silver impregnations. The new genus Apocoleps is characterized by having 8 (vs. 6 in most other related genera) armour tiers, spines at both ends of the cell, 3 adoral organelles and plates with 4 reniform uni-windows. Apocoleps magnus spec. nov. is defined by the following features: body elongated and slightly curved, about 100-120μm×35-45 μm in vivo; anterior tertiary tier plate with four uni-windows, most secondary and main tier plates with four uni-windows, posterior tertiary tier plate with two uni-windows; left plate margin slightly serrated; on average 23 transverse and 22 longitudinal ciliary rows; one terminal contractile vacuole; marine habitat.

  19. First Record and Redefinition of the Qingdao Population of Marine Ciliate Cardiostomatella vermiformis (Kahl, 1928) Corliss, 1960 (Protozoa, Ciliophora)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The living morphology and infraciliature of a marine ciliate, Cardiostomatella vermiformis isolated from a sand beach of the Jiaozhou Bay near Qingdao, China, were investigated by live observation, protargol and silver carbonate impregnation methods. Both the morphological and morphometric data largely agree with former records. Based on the data obtained, an improved diagnosis for Cardiostomatella vermiformis is supplied: Large marine Cardiostomatella with cylindrical body shape and several prolonged caudal cilia; cells in vivo about (90-500)μm × (30-120)μm; macronucleus beaded; single contractile vacuole caudally positioned; buccal apparatus conspicuously small, genus typical; three to six postoral kineties; 96-130 somatic kineties. This species is recorded for the first time in China.

  20. Proteomic approach to reveal the proteins associated with encystment of the ciliate Euplotes encysticus.

    Directory of Open Access Journals (Sweden)

    Jiwu Chen

    Full Text Available In order to identify and reveal the proteins related to encystment of the ciliate Euplotes encysticus, we analyzed variation in the abundance of the proteins isolated from the resting cyst comparing with proteins in the vegetative cell. 2-D electrophoresis, MALDI-TOF MS techniques and Bioinformatics were used for proteome separation, quantification and identification. The comparative proteomics studies revealed 26 proteins with changes on the expression in the resting cysts, including 12 specific proteins and 14 differential proteins. 12 specific proteins and 10 out of the 14 differential proteins were selected and identified by MALDI-TOF MS. The identified specific proteins with known functions included type II cytoskeletal 1, keratin, Nop16 domain containing protein, protein arginine n-methyltransferase, epsilon-trimethyllysine hydroxylase and calpain-like protein. The identified differential proteins with known functions included Lysozyme C, keratinocyte growth factor, lysozyme homolog AT-2, formate acetyltransferase, alpha S1 casein and cold-shock protein. We discussed the functions of these proteins as well as their contribution in the process of encystment. These identified proteins covered a wide range of molecular functions, including gene regulation, RNA regulation, proteins degradation and oxidation resistance, stress response, material transport and cytoskeleton organization. Therefore, differential expression of these proteins was essential for cell morphological and physiological changes during encystment. This suggested that the peculiar proteins and differential proteins might play important roles in the process of the vegetative cells transforming into the resting cysts. These observations may be novel findings that bring new insights into the detailed mechanisms of dormancy.

  1. Evaluate the potential environmental toxicity of quantum dots on ciliated protozoa by microcalorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Qi [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); State Key Laboratory of Virology, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Huang, Shan, E-mail: huangs@whu.edu.cn [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); State Key Laboratory of Virology, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Su, Wei [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); Li, Peiyuan [College of Pharmacy, Guangxi Traditional Chinese Medical University, Nanning 530001 (China); Liang, Zuocui; Ou, Jianzhen; Ma, Jianqiang [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); Liu, Yi, E-mail: prof.liuyi@263.net [State Key Laboratory of Virology, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China)

    2012-11-10

    Highlights: Black-Right-Pointing-Pointer The toxic effects of QDs to T. thermophila BF{sub 5} using a TAM air microcalorimeter. Black-Right-Pointing-Pointer QDs were acutely toxic for T. thermophila BF{sub 5} growth in a dose-dependent manner. Black-Right-Pointing-Pointer The toxicity of different ligands-capped QDs on T. thermophila BF{sub 5} was investigated. Black-Right-Pointing-Pointer QDs could be ingested by cells and affect the morphology of T. thermophila BF{sub 5}. - Abstract: In the present study, we evaluated the toxic effects of mercaptoacetic acid (MAA)-capped CdSe QDs and CdSe/ZnS QDs to particle-ingesting model ciliated protozoa Tetrahymena thermophila BF{sub 5} (T. thermophila BF{sub 5}) by using a TAM air isothermal microcalorimeter. These results suggested that both MAA-CdSe QDs and MAA-CdSe/ZnS QDs were indeed acutely toxic for T. thermophila BF{sub 5} growth in a dose-dependent manner, and the toxicities of both MAA-CdSe QDs and MAA-CdSe/ZnS QDs increased dramatically after UV irradiation due to the liberation of more toxic Cd{sup 2+}, which indicated that the toxicity of MAA-CdSe/ZnS QDs was less than that of MAA-CdSe QDs. Furthermore, the toxicity of different ligands-capped CdSe/ZnS QDs on T. thermophila BF{sub 5} was also investigated. The uptake of MAA-CdSe/ZnS QDs and adenosine 5 Prime -monophosphate (AMP)-CdSe/ZnS QDs by cells and the morphological change during the process of T. thermophila BF{sub 5} growth incubated with these QDs were further studied by fluorescence inverted microscopy.

  2. Emergence of the Terrestrial Ciliate Colpoda cucullus from a Resting Cyst: Rupture of the Cyst Wall by Active Expansion of an Excystment Vacuole

    Science.gov (United States)

    Funadani, Ryoji; Suetomo, Yasutaka; Matsuoka, Tatsuomi

    2013-01-01

    The first sign of excysting Colpoda cucullus cells is the initiation of the pulsation of a contractile vacuole, which is then replaced by a non-pulsating vacuole (excystment vacuole) that continues to expand and finally ruptures the outermost cyst wall (ectocyst) due to inner pressure. A ciliate surrounded by flexible membranes (endocyst) thus emerges. The osmolarity of the excysting cells is estimated to be 140 mOsm L−1 from the relationship between the frequency of contractile vacuole pulsation and the external sucrose concentration. Both the expansion of the excystment vacuole and the emergence of ciliates occurred even when the cysts were immersed in hypertonic medium. In hypotonic medium containing sodium azide (NaN3, a cytochrome c oxidase inhibitor), the contractile vacuole of vegetative cells stopped pulsating and gradually expanded, causing cells to burst. When C. cucullus was induced to encyst in a hypotonic medium containing NaN3, the expansion of the excystment vacuoles was inhibited. These results suggest that the active uptake of water may be responsible for the expansion of the excystment vacuole required for the ectocyst to rupture. PMID:23268793

  3. Ciliate ingestion and digestion: flow cytometric measurements and regrowth of a digestion-resistant campylobacter jejuni

    Science.gov (United States)

    We developed a method to measure ingestion and digestion rates of bacterivorous protists feeding on pathogenic bacteria. We tested this method using the enteric bacteria Campylobacter jejuni and a freshwater colpodid ciliate. Campylobacter and a non-pathogenic bacteria isolated from the environment ...

  4. Experimental identification and analysis of macronuclear non-coding RNAs from the ciliate Tetrahymena thermophila

    DEFF Research Database (Denmark)

    Andersen, Kasper Langebjerg; Nielsen, Henrik

    2012-01-01

    The ciliate Tetrahymena thermophila is an important eukaryotic model organism that has been used in pioneering studies of general phenomena, such as ribozymes, telomeres, chromatin structure and genome reorganization. Recent work has shown that Tetrahymena has many classes of small RNA molecules ...

  5. Modeling the distribution of ciliate protozoa in the reticulo-rumen using linear programming

    NARCIS (Netherlands)

    Hook, S.E.; Dijkstra, J.; Wright, A.G.; McBride, B.W.; France, J.

    2012-01-01

    The flow of ciliate protozoa from the reticulo-rumen is significantly less than expected given the total density of rumen protozoa present. To maintain their numbers in the reticulo-rumen, protozoa can be selectively retained through association with feed particles and the rumen wall. Few mathematic

  6. Ciliated protozoa community of a combined UASB-activated sludge system in southeastern Brazil.

    Science.gov (United States)

    Siqueira-Castro, Isabel Cristina Vidal; Greinert-Goulart, Juliane Araújo; Rossetto, Renato; Guimarães, José Roberto; Franco, Regina Maura Bueno

    2016-12-01

    The aims of the present study were (1) to evaluate the abundance and taxonomic composition of ciliated protozoa in the activated sludge of a full-scale combined anaerobic-aerobic system operating in a tropical country and (2) to study the relationship between the effluent quality, the physicochemical variables, and the ciliates present in the operating system. The total ciliate fauna of the activated sludge of the Piçarrão Wastewater Treatment Plant (Piçarrão WWTP) was composed of 36 morphospecies belonging to 33 genera. These included 21 species observed in the activated sludge samples on the day of collection and 15 species found in cultures. The activated sludge of the Piçarrão WWTP contained a diversified ciliate community composed mainly of indicator organisms. The most frequently occurring morphospecies were Aspidisca cicada, Vorticella spp., Gastronauta aloisi, Acineria uncinata, and Epistylis plicatilis complex. These results showed that satisfactory operating conditions prevailed at the Piçarrão WWTP. In the combined UASB-activated sludge system, the presence of Aspidisca cicada suggests the occurrence of denitrification in the process while the presence of Acineria uncinata and G. alosi indicates the removal of carbonaceous organic matter.

  7. Feeding by heterotrophic dinoflagellates and ciliates on the free-living dinoflagellate Symbiodinium sp. (Clade E).

    Science.gov (United States)

    Jeong, Hae Jin; Lim, An Suk; Yoo, Yeong Du; Lee, Moo Joon; Lee, Kyung Ha; Jang, Tae Young; Lee, Kitack

    2014-01-01

    To investigate heterotrophic protists grazing on Symbiodinium sp., we tested whether the common heterotrophic dinoflagellates Gyrodinium dominans, Gyrodinium moestrupii, Gyrodinium spirale, Oblea rotundata, Oxyrrhis marina, and Polykrikos kofoidii and the ciliates Balanion sp. and Parastrombidinopsis sp. preyed on the free-living dinoflagellate Symbiodinium sp. (clade E). We measured the growth and ingestion rates of O. marina and G. dominans on Symbiodinium sp. as a function of prey concentration. Furthermore, we compared the results to those obtained for other algal prey species. In addition, we measured the growth and ingestion rates of other predators at single prey concentrations at which these rates of O. marina and G. dominans were saturated. All predators tested in the present study, except Balanion sp., preyed on Symbiodinium sp. The specific growth rates of O. marina and G. dominans on Symbiodinium sp. increased rapidly with increasing mean prey concentration < ca. 740-815 ng C/ml (7,400-8,150 cells/ml), but became saturated at higher concentrations. The maximum growth rates of O. marina and G. dominans on Symbiodinium sp. (0.87 and 0.61/d) were much higher than those of G. moestrupii and P. kofoidii (0.11 and 0.04/d). Symbiodinium sp. did not support positive growth of G. spirale, O. rotundata, and Parastrombidinopsis sp. However, the maximum ingestion rates of P. kofoidii and Parastrombidinopsis sp. (6.7-10.0 ng C/predator/d) were much higher than those of O. marina and G. dominans on Symbiodinium sp. (1.9-2.1 ng C/predator/d). The results of the present study suggest that Symbiodinium sp. may increase or maintain the populations of some predators.

  8. A P450 gene associated with robust resistance to DDT in ciliated protozoan, Tetrahymena thermophila by efficient degradation.

    Science.gov (United States)

    Feng, Lifang; Fu, Chengjie; Yuan, Dongxia; Miao, Wei

    2014-04-01

    Analysis of metabolic mechanisms of dichlorodiphenyltrichloroethane (DDT) accumulation and degradation in microorganisms, which could be used to reduce its hazard to higher organisms at the higher in the food chain, have not been investigated. Robust resistance to DDT (grows well in 256 mg/L DDT) and a surprising ability to degrade DDT (more than 70% DDT within 4h) were found in the ciliated protozoan Tetrahymena thermophila. A P450 gene (CYP5013C2) was found to respond specifically to DDT treatment. In the presence of 256 mg/L DDT, cells with overexpressing CYP5013C2 (p450-OE) grew faster and degraded DDT more efficiently than wild-type (WT) cells, while cells with CYP5013C2 partially knocked down (p450-KD) grew slower and exhibited reduced ability to degrade DDT compared to WT cells. Both dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were detected in cells after exposure to DDT, and the concentration of DDD in the p450-OE strain gradually decreased from 0.5 to 4h. Thus, we argue that this P450 gene (CYP5013C2), by efficiently degrading DDT to DDD, is associated with robust resistance to DDT in Tetrahymena, and that a strain overexpressing this gene has the potential to serve as bioreactor that degrades environmental DDT.

  9. Bose-Einstein condensates form in heuristics learned by ciliates deciding to signal 'social' commitments.

    Science.gov (United States)

    Clark, Kevin B

    2010-03-01

    Fringe quantum biology theories often adopt the concept of Bose-Einstein condensation when explaining how consciousness, emotion, perception, learning, and reasoning emerge from operations of intact animal nervous systems and other computational media. However, controversial empirical evidence and mathematical formalism concerning decoherence rates of bioprocesses keep these frameworks from satisfactorily accounting for the physical nature of cognitive-like events. This study, inspired by the discovery that preferential attachment rules computed by complex technological networks obey Bose-Einstein statistics, is the first rigorous attempt to examine whether analogues of Bose-Einstein condensation precipitate learned decision making in live biological systems as bioenergetics optimization predicts. By exploiting the ciliate Spirostomum ambiguum's capacity to learn and store behavioral strategies advertising mating availability into heuristics of topologically invariant computational networks, three distinct phases of strategy use were found to map onto statistical distributions described by Bose-Einstein, Fermi-Dirac, and classical Maxwell-Boltzmann behavior. Ciliates that sensitized or habituated signaling patterns to emit brief periods of either deceptive 'harder-to-get' or altruistic 'easier-to-get' serial escape reactions began testing condensed on initially perceived fittest 'courting' solutions. When these ciliates switched from their first strategy choices, Bose-Einstein condensation of strategy use abruptly dissipated into a Maxwell-Boltzmann computational phase no longer dominated by a single fittest strategy. Recursive trial-and-error strategy searches annealed strategy use back into a condensed phase consistent with performance optimization. 'Social' decisions performed by ciliates showing no nonassociative learning were largely governed by Fermi-Dirac statistics, resulting in degenerate distributions of strategy choices. These findings corroborate

  10. De novo transcriptomes of a mixotrophic and a heterotrophic ciliate from marine plankton.

    Directory of Open Access Journals (Sweden)

    Luciana F Santoferrara

    Full Text Available Studying non-model organisms is crucial in the context of the current development of genomics and transcriptomics for both physiological experimentation and environmental characterization. We investigated the transcriptomes of two marine planktonic ciliates, the mixotrophic oligotrich Strombidium rassoulzadegani and the heterotrophic choreotrich Strombidinopsis sp., and their respective algal food using Illumina RNAseq. Our aim was to characterize the transcriptomes of these contrasting ciliates and to identify genes potentially involved in mixotrophy. We detected approximately 10,000 and 7,600 amino acid sequences for S. rassoulzadegani and Strombidinopsis sp., respectively. About half of these transcripts had significant BLASTP hits (E-value <10-6 against previously-characterized sequences, mostly from the model ciliate Oxytricha trifallax. Transcriptomes from both the mixotroph and the heterotroph species provided similar annotations for GO terms and KEGG pathways. Most of the identified genes were related to housekeeping activity and pathways such as the metabolism of carbohydrates, lipids, amino acids, nucleotides, and vitamins. Although S. rassoulzadegani can keep and use chloroplasts from its prey, we did not find genes clearly linked to chloroplast maintenance and functioning in the transcriptome of this ciliate. While chloroplasts are known sources of reactive oxygen species (ROS, we found the same complement of antioxidant pathways in both ciliates, except for one enzyme possibly linked to ascorbic acid recycling found exclusively in the mixotroph. Contrary to our expectations, we did not find qualitative differences in genes potentially related to mixotrophy. However, these transcriptomes will help to establish a basis for the evaluation of differential gene expression in oligotrichs and choreotrichs and experimental investigation of the costs and benefits of mixotrophy.

  11. Mating of the stichotrichous ciliate Oxytricha trifallax induces production of a class of 27 nt small RNAs derived from the parental macronucleus.

    Directory of Open Access Journals (Sweden)

    Alan M Zahler

    Full Text Available Ciliated protozoans possess two types of nuclei; a transcriptionally silent micronucleus, which serves as the germ line nucleus, and a transcriptionally active macronucleus, which serves as the somatic nucleus. The macronucleus is derived from a new diploid micronucleus after mating, with epigenetic information contributed by the parental macronucleus serving to guide the formation of the new macronucleus. In the stichotrichous ciliate Oxytricha trifallax, the macronuclear DNA is highly processed to yield gene-sized nanochromosomes with telomeres at each end. Here we report that soon after mating of Oxytricha trifallax, abundant 27 nt small RNAs are produced that are not present prior to mating. We performed next generation sequencing of Oxytricha small RNAs from vegetative and mating cells. Using sequence comparisons between macronuclear and micronuclear versions of genes, we found that the 27 nt RNA class derives from the parental macronucleus, not the developing macronucleus. These small RNAs are produced equally from both strands of macronuclear nanochromosomes, but in a highly non-uniform distribution along the length of the nanochromosome, and with a particular depletion in the 30 nt telomere-proximal positions. This production of small RNAs from the parental macronucleus during macronuclear development stands in contrast to the mechanism of epigenetic control in the distantly related ciliate Tetrahymena. In that species, 28-29 nt scanRNAs are produced from the micronucleus and these micronuclear-derived RNAs serve as epigenetic controllers of macronuclear development. Unlike the Tetrahymena scanRNAs, the Oxytricha macronuclear-derived 27 mers are not modified by 2'O-methylation at their 3' ends. We propose models for the role of these "27macRNAs" in macronuclear development.

  12. Isolation and structural characterization of two water-borne pheromones from Euplotes crassus, a ciliate commonly known to carry membrane-bound pheromones.

    Science.gov (United States)

    Alimenti, Claudio; Vallesi, Adriana; Federici, Sergio; di Giuseppe, Graziano; Fernando, Dini; Carratore, Vitale; Luporini, Pierangelo

    2011-01-01

    Ciliates comprise species synthesizing water-diffusible mating type factors or pheromones and species synthesizing insoluble, cell membrane-bound pheromones. Euplotes crassus has traditionally been placed in the latter group. In contrast with this notion, we found that E. crassus is a constitutive pheromone-secreting ciliate, like other Euplotes species. From cell-free filtrate preparations of the E. crassus strain L-2D, we isolated two distinct pheromones, designated as Ec-α and Ec-1, and determined their complete amino acid sequences by combined chemical and genetic approaches. The Ec-α pheromone sequence extends for 56 amino acid residues with six cysteines and shows a molecular mass of 6,183 Da, while the Ec-1 pheromone sequence extends for 45 amino acid residues with 10 cysteines and shows a molecular mass of 4,840 Da. Marked structural differences distinguish the full-length Ec-α and Ec-1 coding sequences, which have been cloned and characterized from the transcriptionally active macronuclear genome. They were taken as clear indication that the Ec-α and Ec-1 pheromones are specified by genes that are not allelic, but likely derived from a duplicated genetic locus of the transcriptionally silent micronuclear genome.

  13. Stem cells in the adult rat spinal cord: plasticity after injury and treadmill training exercise.

    Science.gov (United States)

    Foret, Ariane; Quertainmont, Renaud; Botman, Olivier; Bouhy, Delphine; Amabili, Philippe; Brook, Gary; Schoenen, Jean; Franzen, Rachelle

    2010-02-01

    Ependymal cells located around the central canal of the adult spinal cord are considered as a source of neural stem cells (NSCs) and represent an interesting pool of endogenous stem cells for repair strategies. Physical exercise is known to increase ependymal cell proliferation, while improving functional recovery. In this work, we further characterized those endogenous NSCs within the normal and injured adult rat spinal cord and investigated the effects of treadmill training using immunohistochemical and behavioral studies. In uninjured untrained rats, Sox-2, a NSC marker, was detected in all ependymal cells of the central canal, and also scattered throughout the parenchyma of the spinal cord. Within the lesion, Sox-2 expression increased transiently, while the number of nestin-positive ependymal cells increased with a concomitant enhancement of proliferation, as indicated by the mitotic markers Ki67 and bromo-deoxyuridine. Exercise, which improved functional recovery and autonomous micturition, maintained nestin expression in both injured and uninjured spinal cords, with a positive correlation between locomotor recovery and the number of nestin-positive cells.

  14. The mitochondrial genome sequence of the ciliate Paramecium caudatum reveals a shift in nucleotide composition and codon usage within the genus Paramecium

    Directory of Open Access Journals (Sweden)

    Berendonk Thomas U

    2011-05-01

    Full Text Available Abstract Background Despite the fact that the organization of the ciliate mitochondrial genome is exceptional, only few ciliate mitochondrial genomes have been sequenced until today. All ciliate mitochondrial genomes are linear. They are 40 kb to 47 kb long and contain some 50 tightly packed genes without introns. Earlier studies documented that the mitochondrial guanine + cytosine contents are very different between Paramecium tetraurelia and all studied Tetrahymena species. This raises the question of whether the high mitochondrial G+C content observed in P. tetraurelia is a characteristic property of Paramecium mtDNA, or whether it is an exception of the ciliate mitochondrial genomes known so far. To test this question, we determined the mitochondrial genome sequence of Paramecium caudatum and compared the gene content and sequence properties to the closely related P. tetraurelia. Results The guanine + cytosine content of the P. caudatum mitochondrial genome was significantly lower than that of P. tetraurelia (22.4% vs. 41.2%. This difference in the mitochondrial nucleotide composition was accompanied by significantly different codon usage patterns in both species, i.e. within P. caudatum clearly A/T ending codons dominated, whereas for P. tetraurelia the synonymous codons were more balanced with a higher number of G/C ending codons. Further analyses indicated that the nucleotide composition of most members of the genus Paramecium resembles that of P. caudatum and that the shift observed in P. tetraurelia is restricted to the P. aurelia species complex. Conclusions Surprisingly, the codon usage bias in the P. caudatum mitochondrial genome, exemplified by the effective number of codons, is more similar to the distantly related T. pyriformis and other single-celled eukaryotes such as Chlamydomonas, than to the closely related P. tetraurelia. These differences in base composition and codon usage bias were, however, not reflected in the amino

  15. Cholinergic Enhancement of Cell Proliferation in the Postnatal Neurogenic Niche of the Mammalian Spinal Cord.

    Science.gov (United States)

    Corns, Laura F; Atkinson, Lucy; Daniel, Jill; Edwards, Ian J; New, Lauryn; Deuchars, Jim; Deuchars, Susan A

    2015-09-01

    The region surrounding the central canal (CC) of the spinal cord is a highly plastic area, defined as a postnatal neurogenic niche. Within this region are ependymal cells that can proliferate and differentiate to form new astrocytes and oligodendrocytes following injury and cerebrospinal fluid contacting cells (CSFcCs). The specific environmental conditions, including the modulation by neurotransmitters that influence these cells and their ability to proliferate, are unknown. Here, we show that acetylcholine promotes the proliferation of ependymal cells in mice under both in vitro and in vivo conditions. Using whole cell patch clamp in acute spinal cord slices, acetylcholine directly depolarized ependymal cells and CSFcCs. Antagonism by specific nicotinic acetylcholine receptor (nAChR) antagonists or potentiation by the α7 containing nAChR (α7*nAChR) modulator PNU 120596 revealed that both α7*nAChRs and non-α7*nAChRs mediated the cholinergic responses. Using the nucleoside analogue EdU (5-ethynyl-2'-deoxyuridine) as a marker of cell proliferation, application of α7*nAChR modulators in spinal cord cultures or in vivo induced proliferation in the CC region, producing Sox-2 expressing ependymal cells. Proliferation also increased in the white and grey matter. PNU 120596 administration also increased the proportion of cells coexpressing oligodendrocyte markers. Thus, variation in the availability of acetylcholine can modulate the rate of proliferation of cells in the ependymal cell layer and white and grey matter through α7*nAChRs. This study highlights the need for further investigation into how neurotransmitters regulate the response of the spinal cord to injury or during aging.

  16. Temporal response of endogenous neural progenitor cells following injury to the adult rat spinal cord

    Directory of Open Access Journals (Sweden)

    Yilin eMao

    2016-03-01

    Full Text Available A pool of endogenous neural progenitor cells found in the ependymal layer and the sub-ependymal area of the spinal cord are reported to upregulate nestin in response to traumatic spinal cord injury. These cells could potentially be manipulated within a critical time period offering one innovative approach to the repair of spinal cord injury. However, little is known about the temporal response of endogenous neural progenitor cells following spinal cord injury. This study used a mild contusion injury in rat spinal cord and immunohistochemistry to determine the temporal response of ependymal neural progenitor cells following injury and their correlation to astrocyte activation at the lesion site. The results from the study demonstrated that Nestin staining intensity at the central canal peaked at 24 hours post-injury and then gradually declined over time. Reactive astrocytes double labelled by Nestin and GFAP were found at the lesion edge and commenced to form the glial scar from 1 week after injury. We conclude that the critical time period for manipulating endogenous neural progenitor cells following a spinal cord injury in rats is between 24 hrs when nestin expression in ependymal cells is increased and 1 week when astrocytes are activated in large numbers.

  17. Colonization of periphytic ciliated protozoa on an artificial substrate in mariculture waters with notes on responses to environmental factors

    Institute of Scientific and Technical Information of China (English)

    Jiqiu Li; Henglong Xu; Xiaofeng Lin; Weibo Song

    2009-01-01

    Colonization of periphytic ciliates and their usefulness for monitoring water quality were evaluated using the glass slide method in two enclosed mariculture ponds used to culture crab larva and in a natural seawater reservoir. The results revealed that (1) the ciliate species composition and colonizing process differed between the culturing ponds and the natural reservoir and (2) the dominant ciliate species showed a greater distribution in terms of both the abundance and the occurrence frequency. This study also demonstrated that structural parameters were strongly related to water conditions. For example, the abundance was positively associated with NO-3-N and soluble reactive phosphate (P < 0.05), whereas the species number, species diversity and evenness were negatively correlated with nutrients (e.g. NO-3N and NH3-N) and temperature (P < 0.05). These findings support the evidence that periphytic ciliates are useful bioindicators of water quality in enclosed mariculture ecosystems.

  18. Molecular evidence that phylogenetically diverged ciliates are active in microbial mats of deep-sea cold-seep sediment.

    Science.gov (United States)

    Takishita, Kiyotaka; Kakizoe, Natsuki; Yoshida, Takao; Maruyama, Tadashi

    2010-01-01

    Cold seeps are areas of the seafloor where hydrogen sulfide- and methane-rich fluid seepage occurs, often sustaining chemosynthetic ecosystems. It is well known that both archaea and bacteria oxidize sulfides and methane to produce chemical energy and that several endemic animals use this energy to thrive in cold seeps. On the other hand, there is little knowledge regarding diversity and ecology of microbial eukaryotes in this ecosystem. In this study we isolated environmental RNA and DNA from microbial mats of cold-seep sediment in Sagami Bay, Japan, and retrieved eukaryotic small-subunit ribosomal RNA sequences with polymerase chain reaction methods followed by clone library construction. Most RNA-derived clones obtained were from ciliates, although DNA-derived clones were mainly from the fungus Cryptococcus curvatus, suggesting that ciliates are active in the environment. The ciliate sequences were phylogenetically diverse, and represented eight known class lineages as well as undesignated lineages. Because most ciliates are bacterivorous, it is highly likely that the ciliates for which sequences were recovered play a role in the food web of this ecosystem as grazers of microbial mats. In addition, given that the environment studied is under highly reduced (anoxic) conditions, based on the prokaryotic community structure deduced from T-RFLP profiles, the ciliates detected may be obligatory or facultative anaerobes.

  19. Horizontal gene transfer from Bacteria to rumen Ciliates indicates adaptation to their anaerobic, carbohydrates-rich environment

    Directory of Open Access Journals (Sweden)

    Takenaka Akio

    2006-02-01

    Full Text Available Abstract Background The horizontal transfer of expressed genes from Bacteria into Ciliates which live in close contact with each other in the rumen (the foregut of ruminants was studied using ciliate Expressed Sequence Tags (ESTs. More than 4000 ESTs were sequenced from representatives of the two major groups of rumen Cilates: the order Entodiniomorphida (Entodinium simplex, Entodinium caudatum, Eudiplodinium maggii, Metadinium medium, Diploplastron affine, Polyplastron multivesiculatum and Epidinium ecaudatum and the order Vestibuliferida, previously called Holotricha (Isotricha prostoma, Isotricha intestinalis and Dasytricha ruminantium. Results A comparison of the sequences with the completely sequenced genomes of Eukaryotes and Prokaryotes, followed by large-scale construction and analysis of phylogenies, identified 148 ciliate genes that specifically cluster with genes from the Bacteria and Archaea. The phylogenetic clustering with bacterial genes, coupled with the absence of close relatives of these genes in the Ciliate Tetrahymena thermophila, indicates that they have been acquired via Horizontal Gene Transfer (HGT after the colonization of the gut by the rumen Ciliates. Conclusion Among the HGT candidates, we found an over-representation (>75% of genes involved in metabolism, specifically in the catabolism of complex carbohydrates, a rich food source in the rumen. We propose that the acquisition of these genes has greatly facilitated the Ciliates' colonization of the rumen providing evidence for the role of HGT in the adaptation to new niches.

  20. Horizontal gene transfer from Bacteria to rumen Ciliates indicates adaptation to their anaerobic, carbohydrates-rich environment

    Science.gov (United States)

    Ricard, Guénola; McEwan, Neil R; Dutilh, Bas E; Jouany, Jean-Pierre; Macheboeuf, Didier; Mitsumori, Makoto; McIntosh, Freda M; Michalowski, Tadeusz; Nagamine, Takafumi; Nelson, Nancy; Newbold, Charles J; Nsabimana, Eli; Takenaka, Akio; Thomas, Nadine A; Ushida, Kazunari; Hackstein, Johannes HP; Huynen, Martijn A

    2006-01-01

    Background The horizontal transfer of expressed genes from Bacteria into Ciliates which live in close contact with each other in the rumen (the foregut of ruminants) was studied using ciliate Expressed Sequence Tags (ESTs). More than 4000 ESTs were sequenced from representatives of the two major groups of rumen Cilates: the order Entodiniomorphida (Entodinium simplex, Entodinium caudatum, Eudiplodinium maggii, Metadinium medium, Diploplastron affine, Polyplastron multivesiculatum and Epidinium ecaudatum) and the order Vestibuliferida, previously called Holotricha (Isotricha prostoma, Isotricha intestinalis and Dasytricha ruminantium). Results A comparison of the sequences with the completely sequenced genomes of Eukaryotes and Prokaryotes, followed by large-scale construction and analysis of phylogenies, identified 148 ciliate genes that specifically cluster with genes from the Bacteria and Archaea. The phylogenetic clustering with bacterial genes, coupled with the absence of close relatives of these genes in the Ciliate Tetrahymena thermophila, indicates that they have been acquired via Horizontal Gene Transfer (HGT) after the colonization of the gut by the rumen Ciliates. Conclusion Among the HGT candidates, we found an over-representation (>75%) of genes involved in metabolism, specifically in the catabolism of complex carbohydrates, a rich food source in the rumen. We propose that the acquisition of these genes has greatly facilitated the Ciliates' colonization of the rumen providing evidence for the role of HGT in the adaptation to new niches. PMID:16472398

  1. Developing and Integrating Advanced Movement Features Improves Automated Classification of Ciliate Species.

    Directory of Open Access Journals (Sweden)

    Ali Soleymani

    Full Text Available Recent advances in tracking technologies such as GPS or video tracking systems describe the movement paths of individuals in unprecedented details and are increasingly used in different fields, including ecology. However, extracting information from raw movement data requires advanced analysis techniques, for instance to infer behaviors expressed during a certain period of the recorded trajectory, or gender or species identity in case data is obtained from remote tracking. In this paper, we address how different movement features affect the ability to automatically classify the species identity, using a dataset of unicellular microbes (i.e., ciliates. Previously, morphological attributes and simple movement metrics, such as speed, were used for classifying ciliate species. Here, we demonstrate that adding advanced movement features, in particular such based on discrete wavelet transform, to morphological features can improve classification. These results may have practical applications in automated monitoring of waste water facilities as well as environmental monitoring of aquatic systems.

  2. Assessing mariculture water quality with the structural and functional characteristics of a ciliate community

    Institute of Scientific and Technical Information of China (English)

    LI Jiqiu; XU Henglong; LIN Xiaofeng; AL-RASHEID Khaled A.S.

    2011-01-01

    Ciliated protozoa play important roles in micro-ecosystems, especially in marine biotopes. However, few studies have been carried out on the periphytic, or aufwuch, forms in mariculture waters so far. In this study, we sampled periphytic ciliate communities in two closed mariculture ponds (ponds CP1 and CP2) and a natural seawater reservoir (pond RP) using a glass slide method to evaluate their colonizing processes and general ecological features, as well as their application as water quality indicators. We analyzed species compositions, structural parameters (species number, richness, diversity, evenness, abundance and dBP) and functional parameters (G, Seq, and T90%). Pond RP was characterized by higher levels of structural parameters (except for abundance and dBp) and more equal proportion of the major taxonomic groups. The values of 5eq were significantly higher in pond RP and similar in both pond CP1 and CP2. It was also demonstrated that environmental factors, including NO2-H, NO3-H, NH3-H, soluble reactive phosphate, temperature and pH, were the first principal factors affecting the communities. Among them, temperature and chemical factors were all significantly and negatively correlated with species number (P<0.01), richness (P<0.01), diversity (P<0.01), and positive correlated with abundance (P<0.01). Opposite correlations between pH and structural parameters were observed. This study showed that there were significant differences in species composition, structural parameters and functional parameters of the periphytic ciliate communities among the ponds, which were in agreement with the water quality. Results of this study confirmed the periphytic ciliate communities to be useful bioindicators of water quality in intensive mariculture waters.

  3. Morphological Studies on the Infraciliature of a Planktonic Ciliate, Tintinnopsis brasiliensis (Ciliophora: Tintinina)

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid & Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation after protargol impregnation and was compared with other related congeners. According to the infraciliature, three ciliary groups can be recognized, which reveals a very stable structure among specimens and denotes that the pattern of infraciliature is, apart from the features of the lorica, a highly reliable criterion for species identification.

  4. Unfolding Thermodynamics of Cysteine-Rich Proteins and Molecular Thermal-Adaptation of Marine Ciliates

    Directory of Open Access Journals (Sweden)

    Giorgia Cazzolli

    2013-11-01

    Full Text Available Euplotes nobilii and Euplotes raikovi are phylogenetically closely allied species of marine ciliates, living in polar and temperate waters, respectively. Their evolutional relation and the sharply different temperatures of their natural environments make them ideal organisms to investigate thermal-adaptation. We perform a comparative study of the thermal unfolding of disulfide-rich protein pheromones produced by these ciliates. Recent circular dichroism (CD measurements have shown that the two psychrophilic (E. nobilii and mesophilic (E. raikovi protein families are characterized by very different melting temperatures, despite their close structural homology. The enhanced thermal stability of the E. raikovi pheromones is realized notwithstanding the fact that these proteins form, as a rule, a smaller number of disulfide bonds. We perform Monte Carlo (MC simulations in a structure-based coarse-grained (CG model to show that the higher stability of the E. raikovi pheromones is due to the lower locality of the disulfide bonds, which yields a lower entropy increase in the unfolding process. Our study suggests that the higher stability of the mesophilic E. raikovi phermones is not mainly due to the presence of a strongly hydrophobic core, as it was proposed in the literature. In addition, we argue that the molecular adaptation of these ciliates may have occurred from cold to warm, and not from warm to cold. To provide a testable prediction, we identify a point-mutation of an E. nobilii pheromone that should lead to an unfolding temperature typical of that of E. raikovi pheromones.

  5. Integrative taxonomy of ciliates: Assessment of molecular phylogenetic content and morphological homology testing.

    Science.gov (United States)

    Vďačný, Peter

    2017-02-24

    The very diverse and comparatively complex morphology of ciliates has given rise to numerous taxonomic concepts. However, the information content of the utilized molecular markers has seldom been explored prior to phylogenetic analyses and taxonomic decisions. Likewise, robust testing of morphological homology statements and the apomorphic nature of diagnostic characters of ciliate taxa is rarely carried out. Four phylogenetic techniques that may help address these issues are reviewed. (1) Split spectrum analysis serves to determine the exact number and quality of nucleotide positions supporting individual nodes in phylogenetic trees and to discern long-branch artifacts that cause spurious phylogenies. (2) Network analysis can depict all possible evolutionary trajectories inferable from the dataset and locate and measure the conflict between them. (3) A priori likelihood mapping tests the suitability of data for reconstruction of a well resolved tree, visualizes the tree-likeness of quartets, and assesses the support of an internal branch of a given tree topology. (4) Reconstruction of ancestral morphologies can be applied for analyzing homology and apomorphy statements without circular reasoning. Since these phylogenetic tools are rarely used, their principles and interpretation are introduced and exemplified using various groups of ciliates. Finally, environmental sequencing data are discussed in this light.

  6. Ciliate biogeography in Antarctic and Arctic freshwater ecosystems: endemism or global distribution of species?

    Science.gov (United States)

    Petz, Wolfgang; Valbonesi, Alessandro; Schiftner, Uwe; Quesada, Antonio; Cynan Ellis-Evans, J

    2007-02-01

    Ciliate diversity was investigated in situ in freshwater ecosystems of the maritime (South Shetland Islands, mainly Livingston Island, 63 degrees S) and continental Antarctic (Victoria Land, 75 degrees S), and the High Arctic (Svalbard, 79 degrees N). In total, 334 species from 117 genera were identified in both polar regions, i.e. 210 spp. (98 genera) in the Arctic, 120 spp. (73 genera) in the maritime and 59 spp. (41 genera) in the continental Antarctic. Forty-four species (13% of all species) were common to both Arctic and Antarctic freshwater bodies and 19 spp. to both Antarctic areas (12% of all species). Many taxa are cosmopolitans but some, e.g. Stentor and Metopus spp., are not, and over 20% of the taxa found in any one of the three areas are new to science. Cluster analysis revealed that species similarity between different biotopes (soil, moss) within a study area was higher than between similar biotopes in different regions. Distinct differences in the species composition of freshwater and terrestrial communities indicate that most limnetic ciliates are not ubiquitously distributed. These observations and the low congruence in species composition between both polar areas, within Antarctica and between high- and temperate-latitude water bodies, respectively, suggest that long-distance dispersal of limnetic ciliates is restricted and that some species have a limited geographical distribution.

  7. Ciliates and the rare biosphere-community ecology and population dynamics.

    Science.gov (United States)

    Weisse, Thomas

    2014-01-01

    Application of deep sequencing technologies to environmental samples and some detailed morphological studies suggest that there is a vast, yet unexplored rare ciliate biosphere, tentatively defined in terms of operational taxonomic units. However, very few studies complemented molecular and phylogenetic data with morphological and ecological descriptions of the species inventory. This is mainly because the sampling effort increases strongly with decreasing species abundance. In spite of this limited knowledge, it is clear that species that are rare under certain environmental conditions (temporal rare biosphere) may become abundant when the physical, chemical, and biological variables of their habitat change. Furthermore, some species may always be present in low numbers if their dispersal rates are exceedingly high (accidental rare biosphere). An intriguing question is whether there are some species that are always rare, i.e., in every suitable environment. This permanent rare biosphere is conceptually different from the temporal rare biosphere. This review characterizes typical aquatic habitats of the rare ciliate biosphere, portrays different scenarios under which some or even many species may be permanently rare (background fauna), and identifies some fundamental questions that need to be addressed to achieve a better understanding of the population dynamics of the rare ciliate biosphere.

  8. Chloroplast symbiosis in a marine ciliate: ecophysiology and the risks and rewards of hosting foreign organelles.

    Science.gov (United States)

    McManus, George B; Schoener, Donald M; Haberlandt, Katharine

    2012-01-01

    Simultaneous use of both heterotrophic and autotrophic metabolism ("mixotrophy") is common among protists. Strombidium rassoulzadegani is a planktonic mixotrophic marine ciliate that saves chloroplasts from its algal food and obtains a nutritional subsidy via photosynthesis. Cultures from the northeast, northwest, and southwest Atlantic Ocean show similar numerical response parameters (maximum growth rate, food concentration at which growth is half its maximum, and threshold food concentration for growth), and some isolates have been maintained in vitro for over 3 years. This ciliate grows equally well when fed on the green alga Tetraselmis chui (strain PLY429) or the cryptophyte Rhodomonas lens (strain RHODO). It appears to be an obligate mixotroph, requiring both food and light to achieve positive growth, when feeding on either of these algae. However, it has also been grown for several weeks (>10 generations) heterotrophically on the dinoflagellate Prorocentrum minimum (strain EXUV) during which it grows better in dark than in light. In this paper, we review the ecology of S. rassoulzadegani, discuss some aspects of its photo- and feeding physiology, and speculate on benefits and costs to the ciliate of chloroplast symbiosis.

  9. The water-born protein pheromones of the polar protozoan ciliate, Euplotes nobilii: Coding genes and molecular structures

    Science.gov (United States)

    Vallesi, Adriana; Alimenti, Claudio; Di Giuseppe, Graziano; Dini, Fernando; Pedrini, Bill; Wüthrich, Kurt; Luporini, Pierangelo

    2010-08-01

    The protozoan ciliate Euplotes nobilii found in Antarctic and Arctic coastal waters relies on secretion of water-soluble cell type-specific signal proteins (pheromones) to regulate its vegetative growth and sexual mating. For three of these psychrophilic pheromones we previously determined the three-dimensional structures by nuclear magnetic resonance (NMR) spectroscopy with protein solutions purified from the natural sources, which led to evidence that their adaptation to cold is primarily achieved by increased flexibility through an extension of regions free of regular secondary structures, and by increased exposure of negative charges on the protein surface. Then we cloned the coding genes of these E. nobilii pheromones from the transcriptionally active cell somatic nucleus (macronucleus) and characterized the full-length sequences. These sequences all contain an open reading frame of 252-285 nucleotides, which is specific for a cytoplasmic pheromone precursor that requires two proteolytic cleavages to remove a signal peptide and a pro segment before release of the mature protein into the extracellular environment. The 5‧ and 3‧ non-coding regions are two- to three-fold longer than the coding region and appear to be tightly conserved, probably in relation to the inclusion of intron sequences destined to be alternatively removed to play key regulatory roles in the mechanism of the pheromone gene expression.

  10. Comparison of human nasal epithelial cells grown as explant outgrowth cultures or dissociated tissue cultures in vitro.

    Science.gov (United States)

    Jiao, Jian; Meng, Na; Wang, Hong; Zhang, Luo

    2013-12-01

    The purpose of this study was to compare cell growth characteristics, ciliated cell differentiation, and function of human nasal epithelial cells established as explant outgrowth cultures or dissociated tissue cultures. Human nasal mucosa of the uncinate process was obtained by endoscopy and epithelial cell cultures were established by explant outgrowth or dissociated tissue culture methods. Epithelial cell growth characteristics were observed by inverted phase contrast microscopy. Ciliated cell differentiation was detected by β-tubulin IVand ZO-1 immunocytochemistry. Basal and ATP-stimulated ciliary beat frequency (CBF) was measured using a highspeed digital microscopic imaging system. Both the explant and dissociated tissue cultures established as monolayers with tight junctions and differentiated cell composition, with both types of cultures comprising ciliated and non-ciliated epithelial cells. Fibroblasts were also frequently found in explant cultures but rarely seen in dissociated tissue cultures. In both culture systems, the highest ciliated cell density appeared at 7th-10th culture day and declined with time, with the lifespan of ciliated cells ranging from 14 to 21 days. Overall, 10% of the cells in explant cultures and 20% of the cells in the dissociated tissue cultures were ciliated. These two cultures demonstrated similar ciliary beat frequency values at baseline (7.78 ± 1.99 Hz and 7.91 ± 2.52 Hz, respectively) and reacted equivalently following stimulation with 100 μM ATP. The results of this study indicate that both the explant outgrowth and dissociated tissue culture techniques are suitable for growing well-differentiated nasal ciliated and non-ciliated cells, which have growth characteristics and ciliary activity similar to those of nasal epithelial cells in vivo.

  11. Temporal Response of Endogenous Neural Progenitor Cells Following Injury to the Adult Rat Spinal Cord.

    Science.gov (United States)

    Mao, Yilin; Mathews, Kathryn; Gorrie, Catherine A

    2016-01-01

    A pool of endogenous neural progenitor cells (NPCs) found in the ependymal layer and the sub-ependymal area of the spinal cord are reported to upregulate Nestin in response to traumatic spinal cord injury (SCI). These cells could potentially be manipulated within a critical time period offering an innovative approach to the repair of SCI. However, little is known about the temporal response of endogenous NPCs following SCI. This study used a mild contusion injury in rat spinal cord and immunohistochemistry to determine the temporal response of ependymal NPCs following injury and their correlation to astrocyte activation at the lesion edge. The results from the study demonstrated that Nestin staining intensity at the central canal peaked at 24 h post-injury and then gradually declined over time. Reactive astrocytes double labeled by Nestin and glial fibrillary acidic protein (GFAP) were found at the lesion edge and commenced to form the glial scar from 1 week after injury. We conclude that the critical time period for manipulating endogenous NPCs following a spinal cod injury in rats is between 24 h when Nestin expression in ependymal cells is increased and 1 week when astrocytes are activated in large numbers.

  12. Morphology and morphogenesis of a new marine cyrtophorid ciliate, Hartmannula sinica nov. spec. (Protozoa, Ciliophora, Cyrtophorida) from China.

    Science.gov (United States)

    Shao, Chen; Song, Weibo; Gong, Jun

    2008-02-01

    The living morphology, infraciliature and morphogenesis of a new marine cyrtophorid ciliate, Hartmannula sinica nov. spec., collected from Qingdao, north China, have been investigated. The new species is characterized by: size in vivo 90-130 x 40-50 microm, body long elliptical in outline, cilium-free field covered with a conspicuous alveolar layer; 24-31 ventral kineties, the rightmost 6-9 of which extend apically; 20-24 nematodesmal rods; about 15 sparsely distributed contractile vacuoles; a yellowish pigment spot is always present near the anterior tip of the cell. Morphogenetic events exhibit a pattern, which is homologous with that of related cyrtophorids. The main features are as follows: (1) preoral and circumoral kineties of opisthe develop from the oral primordium that forms in mid-body from sections of 3 postoral kineties, while parental preoral and circumoral kineties are retained; (2) parental cytostome and nematodesmal rods are resorbed in middle divisional stages and then replaced by newly formed structures; (3) the heteromerous macronucleus unifies in the late divisional stage.

  13. Notes on Two Marine Ciliates from the Yellow Sea, China: Placus salinus and Strombidium apolatum (Protozoa, Ciliophora)

    Institute of Scientific and Technical Information of China (English)

    XU Dapeng; SONG Weibo; HU Xiaozhong

    2005-01-01

    The living morphology and infraciliature of two rare marine ciliates, Placus salinus Dietz, 1964 and Strombidium apolatum Wilbert and Song, 2005, collected from the coastal waters near Qingdao, China, were investigated by in vivo observation and protargol impregnation technique. The improved diagnosis for Placus salinus is as follows: medium-sized marine Placus, in vivo (50 -60) μm × (30 -40)μm; cell elliptical to barrel-shaped; 28 -31 somatic kineties; single macronucleus usually ellipsoid and one micronucleus located in the indention of the macronucleus; one contractile vacuole posteriorly positioned. Strombidium apolatum is characterized by: marine strombidium (40-60) μm × (30-45) μm in vivo, cordiform in shape with somewhat pointed posterior end and conspicuous apical protrusion; extrusomes prominent, about 15μm in length and evenly arranged along the circle kinety; about 16 collar and 5-6 buccal membranelles; one elongate macronucleus and one micronucleus; circle and ventral kineties consisting of about 53 and 45 dikinetids respectively.

  14. Morphology of four cyrtophorian ciliates (Protozoa, Ciliophora) from Yangtze Delta, China, with notes on the phylogeny of the genus Phascolodon.

    Science.gov (United States)

    Pan, Hongbo; Wang, Liqing; Jiang, Jiamei; Stoeck, Thorsten

    2016-10-01

    The morphology of four cyrtophorian ciliates, Dysteria ovalis, D. semilunaris, Phascolodon vorticella, and Chlamydonellopsis calkinsi, were investigated using living observation and protargol-staining. The morphology of D. ovalis is revealed in detail for the first time, and it is characterized by the following combination of features: size 40-50×20-30μm in vivo; oval in outline; four right kineties, including two frontoventral kineties and one shortened leftmost right kinety; three left frontal kineties; two ventrally located contractile vacuoles; marine habitat. New Chinese populations of three other species correspond well with previous descriptions, but a well-developed alveolar layer on the cell surface of P. vorticella is reported for the first time. Phylogenetic analyses based on small subunit rRNA gene sequences clustered Dysteria ovalis with Mirodysteria decora, whereas D. semilunaris is grouped with D. lanceolata. Although Phascolodon appeared as sister to Pseudochilodonopsis in the present work, its accurate phylogenetic position is still uncertain because AU test did not reject the possibility that it clustered with Odontochlamys and Chilodonella.

  15. Primary and secondary siRNA synthesis triggered by RNAs from food bacteria in the ciliate Paramecium tetraurelia.

    Science.gov (United States)

    Carradec, Quentin; Götz, Ulrike; Arnaiz, Olivier; Pouch, Juliette; Simon, Martin; Meyer, Eric; Marker, Simone

    2015-02-18

    In various organisms, an efficient RNAi response can be triggered by feeding cells with bacteria producing double-stranded RNA (dsRNA) against an endogenous gene. However, the detailed mechanisms and natural functions of this pathway are not well understood in most cases. Here, we studied siRNA biogenesis from exogenous RNA and its genetic overlap with endogenous RNAi in the ciliate Paramecium tetraurelia by high-throughput sequencing. Using wild-type and mutant strains deficient for dsRNA feeding we found that high levels of primary siRNAs of both strands are processed from the ingested dsRNA trigger by the Dicer Dcr1, the RNA-dependent RNA polymerases Rdr1 and Rdr2 and other factors. We further show that this induces the synthesis of secondary siRNAs spreading along the entire endogenous mRNA, demonstrating the occurrence of both 3'-to-5' and 5'-to-3' transitivity for the first time in the SAR clade of eukaryotes (Stramenopiles, Alveolates, Rhizaria). Secondary siRNAs depend on Rdr2 and show a strong antisense bias; they are produced at much lower levels than primary siRNAs and hardly contribute to RNAi efficiency. We further provide evidence that the Paramecium RNAi machinery also processes single-stranded RNAs from its bacterial food, broadening the possible natural functions of exogenously induced RNAi in this organism.

  16. Act together - implications of symbioses in aquatic ciliates

    DEFF Research Database (Denmark)

    Dziallas, Claudia; Allgaier, Martin; Monaghan, Michael T.;

    2012-01-01

    are globally distributed and have been intensively studied in the context of plastid evolution. Their relatively large cell size offers an ideal habitat for numerous microorganisms with different functional traits including commensalism and parasitism. Phagocytosis facilitates the formation of symbiotic...... relationships, particularly since some ingested microorganisms can escape the digestion. For example, photoautotrophic algae and methanogens represent endosymbionts that greatly extend the biogeochemical functions of their hosts. Consequently, symbiotic relationships between protists and prokaryotes...

  17. Phylogenetic position of Licnophora, Lechriopyla, and Schizocaryum, three unusual ciliates (phylum Ciliophora) endosymbiotic in echinoderms (phylum Echinodermata).

    Science.gov (United States)

    Lynn, Denis H; Strüder-Kypke, Michaela

    2002-01-01

    Various echinoderms are colonized by species from several classes of the Phylum Ciliophora, indicating that the echinoderm "habitat" has been invaded independently on numerous occasions throughout evolutionary history. Two "echinoderm" ciliates whose phylogenetic positions have been problematic are Licnophora macfarlandi Stevens, 1901 and Schizocaryum dogieli Poljansky and Golikova, 1957. Licnophora macfarlandi is an endosymbiont of the respiratory trees of holothuroids, and S. dogieli is found in the esophagus of echinoids. A third species, Lechriopyla mystax Lynch, 1930, is a plagiopylid ciliate found in the intestine of echinoids. Host echinoderms were collected near the Friday Harbor Laboratories, San Juan Island, WA. Specimens of S. dogieli and L. mystax were obtained from the esophagus and intestine, respectively, of the sea urchin Strongylocentrotus pallidus. Specimens of L. macfarlandi were collected from the fluid obtained from the respiratory trees of Parastichopus californicus. Using small subunit ribosomal RNA (SSrRNA) sequences of these three ciliates and a global alignment of SSrRNA sequences of other ciliates, we established the following. 1) Licnophora is a spirotrich ciliate, clearly related to the hypotrichs and stichotrichs; this is corroborated by its possession of macronuclear replication bands. 2) Lechriopyla is the sister genus to Plagiopyla and is a member of the Class Plagiopylea, which was predicted based on its cytology. 3) Schizocaryum clusters in the Class Oligohymenophorea and is most closely related to the scuticociliates; there are currently no morphological features known to relate Schizocaryum to the scuticociliates.

  18. Stomatogenesis in the ditransversal ciliate Homalozoon vermiculare (Ciliophora, Rhabdophora).

    Science.gov (United States)

    Leipe, D D; Oppelt, A; Hausmann, K; Foissner, W

    1992-05-22

    H. vermiculare possesses about 10 somatic kineties on the right lateral side, 3 somatic kineties on the left lateral side and a single circumoral kinety. The somatic kineties are composed of monokinetids exc\\~ept for the anterior ends of the brush kineties which are composed of dikinetids. The circumoral kinety consists of paired kinetosomes one of which is nonciliated and associated with a microtubular lamella and a nematodesma. Stomatogenesis commences when the anteriormost somatic kinetosomes in the opisthe are transformed into the nonciliated kinetosomes of the future oral dikinetid. They lose the somatic infraciliary fibers and the ciliary shaft and each gives rise to a nematodesma and a microtubular ribbon. Adjacent to each of the transformed somatic kinetosomes, a new kinetosome is assembled, thus producing an oral dikinetid anlage. The new anterior kinetosome bears a cilium and becomes the ciliferous kinetosome of the oral wreath of cilia. In protargol stained specimens, proliferation of kinetosomes can first be observed in the left lateral kineties but, eventually, each of the somatic kineties produces one kinetofragment. Thus, H. vermiculare has a holotelokinetal type of stomatogenesis. The cirumoral kinety arises from a counter-clockwise rotation (as viewed from outside the cell) of all 15 dikinetid kinetofragments and subsequent "head to tail" fusion of the fragments after cell division has been completed. The oral apparatus of the proter seems to be largely conserved during division. Some aspects of the evolution of the oral apparatus and the origin of the oral microtubular ribbons are discussed.

  19. Using Sorting by Reversal: Breakpoint Graph for Gene Assembly in Ciliates

    Science.gov (United States)

    Brijder, Robert; Jan Hoogeboom, Hendrik

    2007-09-01

    The theory of gene assembly in ciliates has much in common with the theory of sorting by reversal. Both model processes that are based on splicing, and have a fixed begin and end product. The main difference is the type of splicing operations used to obtain the end product from the begin product. In this overview paper we show that the concept of breakpoint graph, known from the theory of sorting by reversal, has many uses in the theory of gene assembly. Our aim is to present the material in an intuitive and informal manner to allow for an efficient introduction into the subject.

  20. On the marine ciliate, Pseudocohnilembus hargisi (Protozoa, ciliophora, scuticociliatida) with comparison of its related species

    Science.gov (United States)

    Gong, Jun; Ma, Hong-Wei; Song, Wei-Bo

    2002-09-01

    The living morphology, nuclear apparatus, infraciliature and silverline system of the poorly-known ciliate Pseudocohnilembus hargisi Evans & Thompson, 1964, collected from a shrimp culture pond in Qingdao, China, were examined by observation of the live specimen; and by the pyridinated carbonate method and Chatton-Lwoff technique. The main characteristics: 13 14 (usually 13) longitudinal or slightly spirally arranged somatic kineties; single contractile vacuole with usually 2 (1 2) pores at posterior ends of the fourth and fifth somatic kineties to the right of the buccal cavity. Several related congeners were compared and morphometrically tabulated.

  1. ON THE MARINE CILIATE, Pseudocohnilembus hargisi (PROTOZOA,CILIOPHORA, SCUTICOCILIATIDA) WITH COMPARISON OF ITS RELATED SPECIES

    Institute of Scientific and Technical Information of China (English)

    龚骏; 马宏伟; 宋微波

    2002-01-01

    The living morphology, nuclear apparatus, infraciliature and silverline system o f the poorly-known ciliate Pseudocohnilembus hargisi Evans & Thompson, 1964 , collected from a shrimp culture pond in Qingdao, China, were examined by obser vation of the live specimen; and by the pyridinated carbonate method and Chatton -Lwoff technique. The main characteristics: 13-14 (usually 13) longitudinal or slightly spirally arranged somatic kineties; single contractile vacuole with usually 2 ( 1-2) pores at posterior ends of the fourth and fifth somatic kineties to the rig ht of the buccal cavity. Several related congeners were compared and morphometri cally tabulated.

  2. Ciliate protozoa in the rumen of Kafue lechwe, Kobus leche kafuensis, in Zambia, with the description of four new species.

    Science.gov (United States)

    Imai, S; Tsutsumi, Y; Yumura, S; Mulenga, A

    1992-01-01

    The composition of the rumen ciliate fauna in 76 Kafue lechwe inhabiting a limited area in Zambia was surveyed and five genera containing 24 species with 16 formae belonging to the family Ophryoscolecidae were identified. Four new species belonging to Diplodiniinae were recognized and described as Diplodinium lochinvarense n. sp., Diplodinium leche n. sp., Diplodinium zambiense n. sp., and Metadinium ossiculi n. sp. In addition, Ostracodinium gracile form fissilaminatum Dogiel, 1932 was found for the second time and described as Metadinium fissilaminatum n. comb. The species composition was fairly unusual. Seven of the species have been found only in African wild antelopes and these species were found more frequently than cosmopolitan species. There was no evidence of isotrichid species. The average density of ciliates per 1 ml of the rumen fluid was 25.7 x 10(4), and the number of ciliate species per head of host was 10.8.

  3. Listeria monocytogenes virulence factor Listeriolysin O favors bacterial growth in co-culture with the ciliate Tetrahymena pyriformis, causes protozoan encystment and promotes bacterial survival inside cysts

    Directory of Open Access Journals (Sweden)

    Ermolaeva Svetlana A

    2010-01-01

    Full Text Available Abstract Background The gram-positive pathogenic bacterium Listeria monocytogenes is widely spread in the nature. L. monocytogenes was reported to be isolated from soil, water, sewage and sludge. Listeriolysin O (LLO is a L. monocytogenes major virulence factor. In the course of infection in mammals, LLO is required for intracellular survival and apoptosis induction in lymphocytes. In this study, we explored the potential of LLO to promote interactions between L. monocytogenes and the ubiquitous inhabitant of natural ecosystems bacteriovorous free-living ciliate Tetrahymena pyriformis. Results Wild type L. monocytogenes reduced T. pyriformis trophozoite counts and stimulated encystment. The effects were observed starting from 48 h of co-incubation. On the day 14, trophozoites were eliminated from the co-culture while about 5 × 104 cells/ml remained in the axenic T. pyriformis culture. The deficient in the LLO-encoding hly gene L. monocytogenes strain failed to cause mortality among protozoa and to trigger protozoan encystment. Replenishment of the hly gene in the mutant strain restored toxicity towards protozoa and induction of protozoan encystment. The saprophytic non-haemolytic species L. innocua transformed with the LLO-expressing plasmid caused extensive mortality and encystment in ciliates. During the first week of co-incubation, LLO-producing L. monocytogenes demonstrated higher growth rates in association with T. pyriformis than the LLO-deficient isogenic strain. At latter stages of co-incubation bacterial counts were similar for both strains. T. pyriformis cysts infected with wild type L. monocytogenes caused listerial infection in guinea pigs upon ocular and oral inoculation. The infection was proved by bacterial plating from the internal organs. Conclusions The L. monocytogenes virulence factor LLO promotes bacterial survival and growth in the presence of bacteriovorous ciliate T. pyriformis. LLO is responsible for L. monocytogenes

  4. Phosphorus, nitrogen and chlorophyll-a are significant factors controlling ciliate communities in summer in the northern Beibu Gulf, South China Sea.

    Science.gov (United States)

    Wang, Yibo; Zhang, Wenjing; Lin, Yuanshao; Cao, Wenqing; Zheng, Lianming; Yang, Jun

    2014-01-01

    Ciliates (protozoa) are ubiquitous components of plankton community and play important roles in aquatic ecosystems in regards of their abundance, biomass, diversity and energy turnover. Based on the stratified samples collected from the northern Beibu Gulf in August 2011, species composition, abundance, biomass, diversity and spatial pattern of planktonic ciliates were studied. Furthermore the main environmental factors controlling ciliate communities were determined. A total of 101 species belonging to 44 genera and 7 orders (i.e., Oligotrichida, Haptorida, Euplotida, Sessilida, Pleurostomatida, Scuticociliatida and Tintinnida) were identified. The variation of ciliate communities was significant at horizontal level, but that was not at vertical level. Based on cluster analysis, ciliate communities were divided into three main groups. Redundancy analysis (RDA) revealed that Group A, existing in the waters with higher concentration of phosphorus and nitrogen, was dominated by Tintinnidium primitivum. Group B in the waters with lower temperature and chlorophyll-a concentration, was dominated by Leegaardiella ovalis. Group C, existing in the waters with higher temperature and chlorophyll-a concentration, was dominated by large Strombidium spp. and Mesodinium rubrum. Combining multiple analytic methods, our results strongly supported that phosphorus, nitrogen and chlorophyll-a were the most significant factors affecting the ciliate communities in the northern Beibu Gulf in summer. Concentration of phosphorus and nitrogen primarily influenced ciliate biomass, implying a potential impact of eutrophication on ciliate growth. The correlation with chlorophyll-a concentration, on one hand indicate the response of ciliates to the food availability, and on the other hand, the ciliates containing chloroplasts or endosymbionts may contribute greatly to the chlorophyll-a.

  5. Phosphorus, nitrogen and chlorophyll-a are significant factors controlling ciliate communities in summer in the northern Beibu Gulf, South China Sea.

    Directory of Open Access Journals (Sweden)

    Yibo Wang

    Full Text Available Ciliates (protozoa are ubiquitous components of plankton community and play important roles in aquatic ecosystems in regards of their abundance, biomass, diversity and energy turnover. Based on the stratified samples collected from the northern Beibu Gulf in August 2011, species composition, abundance, biomass, diversity and spatial pattern of planktonic ciliates were studied. Furthermore the main environmental factors controlling ciliate communities were determined. A total of 101 species belonging to 44 genera and 7 orders (i.e., Oligotrichida, Haptorida, Euplotida, Sessilida, Pleurostomatida, Scuticociliatida and Tintinnida were identified. The variation of ciliate communities was significant at horizontal level, but that was not at vertical level. Based on cluster analysis, ciliate communities were divided into three main groups. Redundancy analysis (RDA revealed that Group A, existing in the waters with higher concentration of phosphorus and nitrogen, was dominated by Tintinnidium primitivum. Group B in the waters with lower temperature and chlorophyll-a concentration, was dominated by Leegaardiella ovalis. Group C, existing in the waters with higher temperature and chlorophyll-a concentration, was dominated by large Strombidium spp. and Mesodinium rubrum. Combining multiple analytic methods, our results strongly supported that phosphorus, nitrogen and chlorophyll-a were the most significant factors affecting the ciliate communities in the northern Beibu Gulf in summer. Concentration of phosphorus and nitrogen primarily influenced ciliate biomass, implying a potential impact of eutrophication on ciliate growth. The correlation with chlorophyll-a concentration, on one hand indicate the response of ciliates to the food availability, and on the other hand, the ciliates containing chloroplasts or endosymbionts may contribute greatly to the chlorophyll-a.

  6. 83例颅内室管膜肿瘤临床分析%Intracranial ependymal tumour: a clinical study of 83 cases

    Institute of Scientific and Technical Information of China (English)

    唐耀领; 杨玉山

    2011-01-01

    目的 总结颅内室管膜肿瘤的临床特点,探讨其预后相关因素.方法 回顾性总结83例颅内室管膜肿瘤的分布、年龄、病理及影像学特点,分析其手术治疗及辅助治疗的效果.结果 83例颅内室管膜肿瘤中幕下室管膜肿瘤41例,幕上室管膜肿瘤42例.年龄≤15岁37例,>15岁46例.病理按WHO肿瘤组织学分级:Ⅰ~Ⅱ级58例(69.9%),Ⅲ级25例(30.1%).手术全切67例(80.7%),次全切16例(19.3%).5年存活率81.9%(68/83).手术切除程度和病理分级是影响颅内室管膜肿瘤患者预后的高危因素.结论 肿瘤全切可明显改善患者的预后.术后发现肿瘤残留,适.合者可考虑二次手术切除.间变性室管膜瘤预后较差.放疗在颅内室管膜肿瘤的治疗中具有重要作用,化疗作用有限,主要尝试用于婴幼儿以避免放疗的副损害.%Objective To study the clinical features of patients with intracranial ependymal tumour, and explore the prognostic factors which have.a significant association with the outcome. Methods Eighty-three patients with histologically proven ependymal tumour were retrospectively reviewed. The tumour location, the patients' age, the histological features, imaging characteristics, surgical management and adjuvant therapy were studied. Results In 83 cases of intracranial ependymal tumour,41 cases were infratentorial and 42 cases were supratentorial ependymal tumour, 37 patients age ≤15 years, while 46patients age > 15 years. Fifty-eight patients ( 69.9% ) and 25 patients (30.1% ) had low (WHO Ⅰ - Ⅱ ) and high-grade (WHOⅢ) tumors respectively. Sixty-reven (80.7%) patients had gross total resection and 16patients ( 19.3% ) had subtotal resection. The 5-year survival rate was 81.9%( 68/83 ). The factors that were found to have a statistical significance association with the outcome were the extent of the resection and the pathologic characteristics. Conclusions Gross total resection of these tumors results in a good

  7. Novel insights into the genetic diversity of Balantidium and Balantidium-like cyst-forming ciliates.

    Directory of Open Access Journals (Sweden)

    Kateřina Pomajbíková

    Full Text Available Balantidiasis is considered a neglected zoonotic disease with pigs serving as reservoir hosts. However, Balantidium coli has been recorded in many other mammalian species, including primates. Here, we evaluated the genetic diversity of B. coli in non-human primates using two gene markers (SSrDNA and ITS1-5.8SDNA-ITS2. We analyzed 49 isolates of ciliates from fecal samples originating from 11 species of captive and wild primates, domestic pigs and wild boar. The phylogenetic trees were computed using Bayesian inference and Maximum likelihood. Balantidium entozoon from edible frog and Buxtonella sulcata from cattle were included in the analyses as the closest relatives of B. coli, as well as reference sequences of vestibuliferids. The SSrDNA tree showed the same phylogenetic diversification of B. coli at genus level as the tree constructed based on the ITS region. Based on the polymorphism of SSrDNA sequences, the type species of the genus, namely B. entozoon, appeared to be phylogenetically distinct from B. coli. Thus, we propose a new genus Neobalantidium for the homeothermic clade. Moreover, several isolates from both captive and wild primates (excluding great apes clustered with B. sulcata with high support, suggesting the existence of a new species within this genus. The cysts of Buxtonella and Neobalantidium are morphologically indistinguishable and the presence of Buxtonella-like ciliates in primates opens the question about possible occurrence of these pathogens in humans.

  8. Evolutionary relationship and species separation of four morphologically similar stichotrichous ciliates (Protozoa,Ciliophora)

    Institute of Scientific and Technical Information of China (English)

    Zhenzhen Yi; John Clamp; Khaled A.S.A1-Rasheid; Abdulaziz A.Al-Khedhairy; Zigui Chen; Weibo Song

    2009-01-01

    Phylogenetic and taxonomic studies on ciliate protists using molecular approaches have been demonstrated to be very reliable to form strong conclusions and results.In the present work,species separation of some morphologically similar stichotrichous ciliates,two species of Pseudokeronopsis and two species of Apokeronopsis,was reexamined using amplified ribosomal DNA restriction analysis (PCRRFLP).Five of 10 restriction enzymes revealed species-specific polymorphic patterns,of which four similar stichotrichs could be significantly separated and identified.Among them,EcoR I offered almost no significantly different restriction fragment patterns,but the four species could be separated from one another and identified with Hae III.Distinctly different restriction digestion haplotypes and similarity indices separated the species,and were used to construct a phylogeny.Phylogenies based on ITS2 nucleotide sequences and ITS2 secondary structures supported the separation of Pseudokeronopsis and Apokeronopsis using RFLP analysis,although three Pseudokeronopsis carnea populations did not cluster together.In addition,phylogenetic analyses using multiple algorithms confirmed that these two genera formed two distinct groups within the urostylids.(C) 2008 National Natural Science Foundation of China and Chinese Academy of Sciences.Published by Elsevier Limited and Science in China Press.All rights reserved.

  9. A cover of glass: first report of biomineralized silicon in a ciliate, Maryna umbrellata (Ciliophora: Colpodea).

    Science.gov (United States)

    Foissner, Wilhelm; Weissenbacher, Birgit; Krautgartner, Wolf-Dietrich; Lütz-Meindl, Ursula

    2009-01-01

    Using hydrofluoric acid, scanning electron microscope-assisted X-ray microanalysis, and energy-filtered transmission electron microscopy, we present the first definite proof of biomineralized silicon [(SiO(2))](n) in a ciliophoran protist, Maryna umbrellata, a common inhabitant of ephemeral pools. In the trophic specimen, the amorphic silicon (glass) granules are accumulated in the anterior half of the body. When entering the dormant stage, most glass granules are excreted to form the surface cover of the globular resting cyst. Most likely, the silicon granules are synthesized in vesicles of the Golgi apparatus. First, nanospheres with a size of 20-40 nm are formed in a fibrous matrix; they grow to be spongious complexes, eventually becoming amorphous glass granules with an average size of 819 nm x 630 nm. In the transmission electron microscope, the silicon granules show the characteristic fracture pattern of glass known from many other silicon-bearing organisms. A literature survey suggests that silicon is very rare in ciliates. The fine structure and genesis of silicon granules in M. umbrellata are very similar to those of other organisms, including vascular plants and animals, indicating a common mechanism. Light perception and protection against mechanical stress and predators might be functions of the silicon granules in M. umbrellata. The palaeontological significance of glass cysts in ciliates is also discussed.

  10. Diversity of apostome ciliates, Chromidina spp. (Oligohymenophorea, Opalinopsidae), parasites of cephalopods of the Mediterranean Sea

    Science.gov (United States)

    2016-01-01

    Chromidina spp. are enigmatic apostome ciliates (Oligohymenophorea, Opalinopsidae) that parasitise the renal and pancreatic appendages of cephalopods. Only four species have been described, among which only three have been formally named. No DNA sequence has been reported so far. To investigate Chromidina spp. diversity, we sampled cephalopods in the Mediterranean Sea off Tunis, Tunisia, and identified two distinct Chromidina spp. in two different host species: Loligo vulgaris and Sepia officinalis. From haematoxylin-stained slides, we described morphological traits for these parasitic species and compared them to previous descriptions. We also re-described the morphology of Chromidina elegans (Foettinger, 1881) from Chatton and Lwoff’s original materials and designated a neohapantotype and paraneohapantotypes for this species. We describe a new species, Chromidina chattoni Souidenne, Florent and Grellier n. sp., found in L. vulgaris off Tunisia, and evidence for a probable novel species, found in S. officinalis off Tunisia, although this latter species presents similarities to some morphological stages previously described for Chromidina cortezi Hochberg, 1971. We amplified, for the first time, an 18S rDNA marker for these two Chromidina species. Phylogenetic analysis supports the association of Chromidina within apostome ciliates. Genetic distance analysis between 18S rDNA sequences of representative apostomes indicates Pseudocollinia as the most closely related genus to Chromidina. PMID:27530149

  11. Diversity of apostome ciliates, Chromidina spp. (Oligohymenophorea, Opalinopsidae, parasites of cephalopods of the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Souidenne Dhikra

    2016-01-01

    Full Text Available Chromidina spp. are enigmatic apostome ciliates (Oligohymenophorea, Opalinopsidae that parasitise the renal and pancreatic appendages of cephalopods. Only four species have been described, among which only three have been formally named. No DNA sequence has been reported so far. To investigate Chromidina spp. diversity, we sampled cephalopods in the Mediterranean Sea off Tunis, Tunisia, and identified two distinct Chromidina spp. in two different host species: Loligo vulgaris and Sepia officinalis. From haematoxylin-stained slides, we described morphological traits for these parasitic species and compared them to previous descriptions. We also re-described the morphology of Chromidina elegans (Foettinger, 1881 from Chatton and Lwoff’s original materials and designated a neohapantotype and paraneohapantotypes for this species. We describe a new species, Chromidina chattoni Souidenne, Florent and Grellier n. sp., found in L. vulgaris off Tunisia, and evidence for a probable novel species, found in S. officinalis off Tunisia, although this latter species presents similarities to some morphological stages previously described for Chromidina cortezi Hochberg, 1971. We amplified, for the first time, an 18S rDNA marker for these two Chromidina species. Phylogenetic analysis supports the association of Chromidina within apostome ciliates. Genetic distance analysis between 18S rDNA sequences of representative apostomes indicates Pseudocollinia as the most closely related genus to Chromidina.

  12. Evolutionary dynamics of a conserved sequence motif in the ribosomal genes of the ciliate Paramecium

    Directory of Open Access Journals (Sweden)

    Lynch Michael

    2010-05-01

    Full Text Available Abstract Background In protozoa, the identification of preserved motifs by comparative genomics is often impeded by difficulties to generate reliable alignments for non-coding sequences. Moreover, the evolutionary dynamics of regulatory elements in 3' untranslated regions (both in protozoa and metazoa remains a virtually unexplored issue. Results By screening Paramecium tetraurelia's 3' untranslated regions for 8-mers that were previously found to be preserved in mammalian 3' UTRs, we detect and characterize a motif that is distinctly conserved in the ribosomal genes of this ciliate. The motif appears to be conserved across Paramecium aurelia species but is absent from the ribosomal genes of four additional non-Paramecium species surveyed, including another ciliate, Tetrahymena thermophila. Motif-free ribosomal genes retain fewer paralogs in the genome and appear to be lost more rapidly relative to motif-containing genes. Features associated with the discovered preserved motif are consistent with this 8-mer playing a role in post-transcriptional regulation. Conclusions Our observations 1 shed light on the evolution of a putative regulatory motif across large phylogenetic distances; 2 are expected to facilitate the understanding of the modulation of ribosomal genes expression in Paramecium; and 3 reveal a largely unexplored--and presumably not restricted to Paramecium--association between the presence/absence of a DNA motif and the evolutionary fate of its host genes.

  13. Non-invasive sources of cells with primary cilia from pediatric and adult patients

    NARCIS (Netherlands)

    Ajzenberg, H.; Slaats, G.G.; Stokman, M.F.; Arts, H.H.; Logister, I.; Kroes, H.Y.; Renkema, K.Y.; Haelst, M.M. van; Terhal, P.A.; Rooij, I.A.L.M. van; Keijzer-Veen, M.G.; Knoers, N.V.; Lilien, M.R.; Jewett, M.A.; Giles, R.H.

    2015-01-01

    BACKGROUND: Ciliopathies give rise to a multitude of organ-specific pathologies; obtaining relevant primary patient material is useful for both diagnostics and research. However, acquisition of primary ciliated cells from patients, particularly pediatric patients, presents multiple difficulties. Bio

  14. Meiosis gene inventory of four ciliates reveals the prevalence of a synaptonemal complex-independent crossover pathway.

    Science.gov (United States)

    Chi, Jingyun; Mahé, Frédéric; Loidl, Josef; Logsdon, John; Dunthorn, Micah

    2014-03-01

    To establish which meiosis genes are present in ciliates, and to look for clues as to which recombination pathways may be treaded by them, four genomes were inventoried for 11 meiosis-specific and 40 meiosis-related genes. We found that the set of meiosis genes shared by Tetrahymena thermophila, Paramecium tetraurelia, Ichthyophthirius multifiliis, and Oxytricha trifallax is consistent with the prevalence of a Mus81-dependent class II crossover pathway that is considered secondary in most model eukaryotes. There is little evidence for a canonical class I crossover pathway that requires the formation of a synaptonemal complex (SC). This gene inventory suggests that meiotic processes in ciliates largely depend on mitotic repair proteins for executing meiotic recombination. We propose that class I crossovers and SCs were reduced sometime during the evolution of ciliates. Consistent with this reduction, we provide microscopic evidence for the presence only of degenerate SCs in Stylonychia mytilus. In addition, lower nonsynonymous to synonymous mutation rates of some of the meiosis genes suggest that, in contrast to most other nuclear genes analyzed so far, meiosis genes in ciliates are largely evolving at a slower rate than those genes in fungi and animals.

  15. UV Radiation and Visible Light Induce hsp70 Gene Expression in the Antarctic Psychrophilic Ciliate Euplotes focardii.

    Science.gov (United States)

    Fulgentini, Lorenzo; Passini, Valerio; Colombetti, Giuliano; Miceli, Cristina; La Terza, Antonietta; Marangoni, Roberto

    2015-08-01

    The psychrophilic ciliate Euplotes focardii inhabits the shallow marine coastal sediments of Antarctica, where, over millions of years of evolution, it has reached a strict molecular adaptation to such a constant-temperature environment (about -2 °C). This long evolution at sub-zero temperatures has made E. focardii unable to respond to heat stress with the activation of its heat shock protein (hsp) 70 genes. These genes can, however, be expressed in response to other stresses, like the oxidative one, thus indicating that the molecular adaptation has exclusively altered the heat stress signaling pathways, while it has preserved hsp70 gene activation in response to other environmental stressors. Since radiative stress has proved to be affine to oxidative stress in several organisms, we investigated the capability of UV radiation to induce hsp70 transcription. E. focardii cell cultures were exposed to several different irradiation regimes, ranging from visible only to a mixture of visible, UV-A and UV-B. The irradiation values of each spectral band have been set to be comparable with those recorded in a typical Antarctic spring. Using Northern blot analysis, we measured the expression level of hsp70 immediately after irradiation (0-h-labeled samples), 1 h, and 2 h from the end of the irradiation. Surprisingly, our results showed that besides UV radiation, the visible light was also able to induce hsp70 expression in E. focardii. Moreover, spectrophotometric measurements have revealed no detectable endogenous pigments in E. focardii, making it difficult to propose a possible explanation for the visible light induction of its hsp70 genes. Further research is needed to conclusively clarify this point.

  16. Composition and distribution of planktonic ciliates in the southern South China Sea during late summer: Comparison between surface and 75 m deep layer

    Science.gov (United States)

    Liu, Huaxue; Shen, Pingping; Li, Chunhou; Chen, Zuozhi; Qi, Zhanhui; Huang, Honghui

    2016-02-01

    Ciliates are very important components in most marine ecosystem. They are trophic link between the microbial food web and grazing food chain. In this study, ciliates were collected from 11 sites in the southern South China Sea (SCS) during August 25 to September 28, 2011. Their composition and distribution at the surface and 75 m deep depth of the ocean were studied. A total of 30 species belonging to 22 genera were identified, and 22 species of 15 genera were Tintinnids. Eutintinnus fraknoii and E. stramentus were the most common species. The other dominants were strombidiids ciliates including Strombidium conicum and S. globosaneum, which were followed by the tide form, Mesodinium pulex. Ciliates abundance ranged from 46 ind L-1 to 368 ind L-1 in the open sites, 46-368 ind L-1 at surface and 73-198 ind L-1 at 75 m deep layer. In the Yongshu reef, ciliates abundance ranged from 167 ind L-1 to 365 ind L-1 in the water column, similar to that in Sanya coral reef waters. Ciliates composition showed obvious difference between surface and 75 m deep layer at station S2 ( P deep layer, salinity was negatively related to mixed layer depth ( P < 0.05), but positively to chlorophyll a concentration ( P < 0.05), indicating that the change of vertical mixing in water column influenced vertical distribution of ciliates in the southern SCS.

  17. Tolerance of ciliated protozoan Paramecium bursaria (Protozoa,Ciliophora) to ammonia and nitrites

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The tolerance to ammonia and nitrites in freshwater ciliate Paramecium bursaria was measured in a conventional open system. The ciliate was exposed to different concentrations of ammonia and nitrites for 2h and 12h in order to determine the lethal concentrations. Linear regression analysis revealed that the 2h-LC50 value for ammonia was 95.94 mg/L and for nitrite 27.35 mg/L using probit scale method (with 95% confidence intervals). There was a linear correlation between the mortality probit scale and logarithmic concentration of ammonia which fit by a regression equation y=7.32x-9.51 (R2=0.98; y, mortality probit scale; x, logarithmic concentration of ammonia), by which 2 h-LC50 value for ammonia was fotnd to be 95.50 mg/L. A linear correlation between mortality probit scales and logarithmic concentration of nitrite is also followed the regression equation y=2.86x+0.89 (R2=0.95; y, mortality probit scale; x, logarithmic concentration of nitrite). The regression analysis of toxicity curves showed that the linear correlation between exposed time of ammonia-N LC50 value and ammonia-N LC50 value followed the regression equation y=2862.85e-0.0ax (R2=0.95; y, duration of exposure to LC50 value; x, LC50 value), and that between exposed time of nitrite-N LC50 value and nitrite-N LC50 value followed the regression equation y = 127.15e-0.13x (R2=0.91; y, exposed time of LC50 value; x, LC50 value). The results demonstrate that the tolerance to ammonia in P. bursaria is considerably higher than that of the larvae or juveniles of some metozoa, e.g. cultured prawns and oysters. In addition, ciliates, as bacterial predators, are likely to play a positive role in maintaining and improving water quality in aquatic environments with high-level ammonium, such as sewage treatment systems.

  18. Spatiotemporal variation in community structure of marine benthic ciliates in the Yellow Sea during and after macroalgal and giant jellyfish blooms

    Science.gov (United States)

    Zhou, Bailing; Xu, Kuidong

    2016-07-01

    The annual bloom of the green macroalgal Ulva prolifera from May through July since 2008 and another of giant jellyfish Nemopilema nomurai from June through September have been frequent events in the Yellow Sea. However, the patterns of benthic ciliate communities during and after the blooms are still not known. In combination with analyses of benthic environmental factors, we investigated the distribution and community composition of benthic ciliates in the Yellow Sea in July and November 2011. In July, ciliates had high standing crops and diversity in the northern Yellow Sea, and in the inshore area off the southern Shandong Peninsula, where large numbers of green macroalgae accumulated. In November, the abundance, biomass and diversity of ciliates were high in the sea areas off the Shandong Peninsula and Changjiang estuary, where a large quantity of jellyfish occurred in August. Neither the abundance nor the biomass had significant difference between seasons, or between different compartments of the Yellow Sea. The species number, and both Margalef and Shannon-Wiener indices of ciliates were all significantly higher in November than in July. In both seasons, prostomateans and karyorelicteans consistently constituted the first and second most important ciliate groups in biomass; and carnivorous ciliates constituted the primary feeding type in terms of biomass as well as species richness, followed by bacterivores, algivores and omnivores. Compared with that in June 2007 when no macroalgae occurred, the percentage of small-sized bacterivores (e.g. Metacystis spp., Euplotes spp. and scuticociliates) increased in July 2011. The proportion of carnivorous ciliates increased in November, and this increased dominance of carnivorous ciliates may be a response to the increase in predominance of heterotrophic nanoflagellates, which might in turn be ascribed to an effect of green macroalgal and giant jellyfish blooms in the Yellow Sea.

  19. A simplified experimental model for clearance of some pathogenic bacteria using common bacterivorous ciliated spp. in Tigris river

    Science.gov (United States)

    Ali, Talib Hassan; Saleh, Dhuha Saad

    2014-03-01

    Bacteria-specific uptake rates of three different protozoan taxa on a pure and mixed bacterial community was studied by means of a simplified and functionally reproducible experimental model. The bacterial species Shigella flexneri, Escherichia coli and Salmonella typhi were isolated and classified from stool samples of patients suffering from diarrhea. Paramecium caudatum, Tetrahymena pyriformis and Halteria grandinella, free living ciliate Protozoans, were isolated and identified from Tigris river water. Pure and mixed ( E. coli + S. typhi), ( E. coli + Sh. flexneri) bacterial cultures were used with each ciliate genera to evaluate the following: predator duplication rate, prey reduction rate, clearance rate and net grazing rate. We used selective lactose fermentation phenomena of enteric bacteria on MacConkey medium for the quantification of bacteria cultural characteristics. The final bacteria concentration was reduced by growing protozoa of 98-99.9 % compared to protozoa-free controls. It showed that Tetrahymena pyriformis had the highest duplication rate (4.13 time/day) in both types of cultures (pure and mixed), followed by Paramecium caudatum and Halteria grandinella, respectively. Paramecium caudatum had the highest rate of ingestion in both types of cultures (26 × 103 bacteria/organism/hr) and yielded the longest time required for 90 % bacterial reduction in a pure suspension of S. typhi (166 h). Clearance rates of pathogenic bacteria by ciliates ranged between 106 nanoliter/organism/h by P. caudatum to S. typhi and 1.92 nanoliter/organism/h seen in T. pyriformis in ( E. coli + S. typhi) mixed culture. We used aquatic experimental microcosms under controlled conditions to explore bacteria-dependent ciliate growth and examined whether these ciliates could discriminate between equally sized bacterial preys in a mixture.

  20. Importance and nutritional value of large ciliates for the reproduction of Acartia clausi during the post spring-bloom period in the North Sea

    DEFF Research Database (Denmark)

    Dutz, Jörg; Peters, J.

    2008-01-01

    enriched with large prey (> 20 mu m). The mineral (C, N) and lipid contents of the food suspensions were determined for size-fractionated samples to characterize the nutritional composition of prey. Large oligotrich ciliates and Strobiliidae dominated the seston biomass. Ciliates, particularly...... of the mineral and lipid content confirmed a high seston nutritional quality. The 20 to 48 mu m fraction reflected the composition of female diets and indicated an enrichment of N and polyunsaturated fatty acids (PUFA) in the diet compared to total seston. The fraction > 48 mu m consisted mostly of ciliates...

  1. Ciliated Median Raphe Cyst of Perineum Presenting as Perianal Polyp: A Case Report with Immunohistochemical Study, Review of Literature, and Pathogenesis

    Directory of Open Access Journals (Sweden)

    Jayesh Sagar

    2006-01-01

    Full Text Available Median raphe cyst is a very rare, benign congenital lesion occurring mainly on the ventral aspect of the penis, but can develop anywhere in the midline between the external urethral meatus and anus. We report a case of median raphe cyst in the perineum presenting as a perianal polyp in a 65-year-old, English white male with exceptionally rare ciliated epithelium. According to our knowledge, this is the third such case of ciliated median raphe cyst in the English literature. This case, also the first case of ciliated median raphe cyst in the perineum location, focuses on pathogenesis of median raphe cyst.

  2. New Record of Two Marine Ciliates (Ciliophora: Spirotrichea in South Korea

    Directory of Open Access Journals (Sweden)

    Kang-San Kim

    2013-04-01

    Full Text Available Two marine hypotrichous ciliates, Anteholosticha petzi and Ponturostyla enigmatica, were collected from the Yellow Sea and the Korea Strait, respectively, and described using live observation and protargol-impregnated specimens. Furthermore, the nuclear small subunit ribosomal RNA gene of each was sequenced and compared to previously annotated sequences retrieved from the GenBank. Anteholosticha petzi is characterized by 3 frontal cirri (FC, 2 frontoterminal cirri (FTC, 8-12 transverse cirri (TC, 1 buccal cirrus (BC, 9-12 midventral pairs (MP, 3 bipolar dorsal kineties (DK, and 3 types of colorless cortical granules. Ponturostyla enigmatica is characterized by 8 FC, 5 ventral cirri (VC, 5-7 TC, 6-7 marginal rows (MR on each side, 4 complete and 2-3 partial DK, and greenish cortical granules. This is the first identification and description of these 2 species, A. petzi and P. enigmatica, in South Korea.

  3. Physical hydrodynamic propulsion model study on creeping viscous flow through a ciliated porous tube

    Indian Academy of Sciences (India)

    NOREEN SHER AKBAR; ADIL WAHID BUTT; DHARMENDRA TRIPATHI; O ANWAR BÉG

    2017-03-01

    The present investigation focusses on a mathematical study of creeping viscous flow induced by metachronal wave propagation in a horizontal ciliated tube containing porous media. Creeping flow limitations are imposed, i.e. inertial forces are small compared to viscous forces and therefore a very low Reynolds number (Re $\\ll$ 1) is taken into account. The wavelength of metachronal wave is also considered to be very large for cilia movement. The physical problem is linearized and exact solutions are developed for the differential equation problem. Mathematica software is used to compute and illustrate numerical results. The influence of slip parameter and Darcy number on velocity profile, pressure gradient and trapping of bolus are discussed with the aid of graphs. It is found that with increasing magnitude of the slip parameter, the trapped bolus inside the streamlines increases in size. The study is relevant to biological propulsion of medical micromachines in drug delivery.

  4. Current status of parasitic ciliates Chilodonella spp. (Phyllopharyngea: Chilodonellidae) in freshwater fish aquaculture.

    Science.gov (United States)

    Bastos Gomes, G; Jerry, D R; Miller, T L; Hutson, K S

    2016-07-30

    Freshwater fish farming contributes to more than two-thirds of global aquaculture production. Parasitic ciliates are one of the largest causes of production loss in freshwater farmed fishes, with species from the genus Chilodonella being particularly problematic. While Chilodonella spp. include 'free-living' fauna, some species are involved in mortality events of fish, particularly in high-density aquaculture. Indeed, chilodonellosis causes major productivity losses in over 16 species of farmed freshwater fishes in more than 14 countries. Traditionally, Chilodonella species are identified based on morphological features; however, the genus comprises yet uncharacterized cryptic species, which indicates the necessity for molecular diagnostic methods. This review synthesizes current knowledge on the biology, ecology and geographic distribution of harmful Chilodonella spp. and examines pathological signs, diagnostic methods and treatments. Recent advances in molecular diagnostics and the ability to culture Chilodonella spp. in vitro will enable the development of preventative management practices and sustained freshwater fish aquaculture production.

  5. Thermodynamic Stability of Psychrophilic and Mesophilic Pheromones of the Protozoan Ciliate Euplotes

    Directory of Open Access Journals (Sweden)

    Kurt Wüthrich

    2013-01-01

    Full Text Available Three psychrophilic protein pheromones (En-1, En-2 and En-6 from the polar ciliate, Euplotes nobilii, and six mesophilic pheromones (Er-1, Er-2, Er-10, Er-11, Er-22 and Er-23 from the temperate-water sister species, Euplotes raikovi, were studied in aqueous solution for their thermal unfolding and refolding based on the temperature dependence of their circular dichroism (CD spectra. The three psychrophilic proteins showed thermal unfolding with mid points in the temperature range 55–70 °C. In contrast, no unfolding was observed for any of the six mesophilic proteins and their regular secondary structures were maintained up to 95 °C. Possible causes of these differences are discussed based on comparisons of the NMR structures of the nine proteins.

  6. Epibiotic ciliates Scyphidia sp. and diatoms on Tigriopus fulvus (Copepoda: Harpacticoida exoskeleton

    Directory of Open Access Journals (Sweden)

    Luigi Pane

    2014-12-01

    Full Text Available Several microorganisms – epibionts – can adhere to living supports taking advantage for their survival, feeding and movement. Epibiosis occurs particularly in aquatic environments, on both benthic and planktonic organisms, among which copepods and cladocerans represent an important living support. The harpacticoid copepod Tigriopus fulvus, living in the splashpools of rocky coasts, was studied to recognize the occurrence of epibionts on the exoskeleton surface using scanning electon microscopy techniques. The first evidence of ciliate Scyphidia sp. on Tigriopus fulvus has been described and the occurrence of algae Cocconeis sp. has been observed as well. Epibionts were found to adhere to antennae, a site linked to the exploitation of water currents carrying food particles to mouthparts and to swimming legs. The reason of the occurrence on swimming legs is less clear and needs further observations. Pertinent results are described and discussed and the influence of epibionts on life cycle and behavior of Tigriopus fulvus is considered.

  7. Divisional morphogenesis in the marine ciliate Anteholosticha manca(Kahl,1932) Berger,2003(Ciliophora: Urostylida)

    Institute of Scientific and Technical Information of China (English)

    LI Liqiong; HU Xiaozhong; WARREN Alan; AL-RASHEID Khaled A S; AL - FARRAJ Saleh A; SHAO Chen; SONG Weibo

    2008-01-01

    The cortical development and macronuclear evolution of the marine hypotrichous ciliate Anteholosticha manca,collected from the coastal waters near Qingdao,China,were investigated using the protargol impregnation method.The morphogenesis of A.manca is generally typical for the genus,and can be characterized as the following features:(1) in the proter,a new oral primordium is formed on the bottom (beneath the pellicle) of the buccal cavity,disorganization of the parental undulating membranes do not contribute to the formation of this primordium; (2) FVT-cirral anlagen in both dividers develop independently,and very likely on-ly a few midventral cirri join in the formation of these primordia; (3) both marginal row and dorsal kinety anlagen develop intraki-netally within the parental structure; (4) at the middle stage,macronuclear segments fuse together to form a single mass as ob-served in most of its related forms.

  8. Physical hydrodynamic propulsion model study on creeping viscous flow through a ciliated porous tube

    Science.gov (United States)

    Akbar, Noreen Sher; Butt, Adil Wahid; Tripathi, Dharmendra; Bég, O. Anwar

    2017-03-01

    The present investigation focusses on a mathematical study of creeping viscous flow induced by metachronal wave propagation in a horizontal ciliated tube containing porous media. Creeping flow limitations are imposed, i.e. inertial forces are small compared to viscous forces and therefore a very low Reynolds number (Re ≪ 1) is taken into account. The wavelength of metachronal wave is also considered to be very large for cilia movement. The physical problem is linearized and exact solutions are developed for the differential equation problem. Mathematica software is used to compute and illustrate numerical results. The influence of slip parameter and Darcy number on velocity profile, pressure gradient and trapping of bolus are discussed with the aid of graphs. It is found that with increasing magnitude of the slip parameter, the trapped bolus inside the streamlines increases in size. The study is relevant to biological propulsion of medical micromachines in drug delivery.

  9. Population dynamics of marine ciliate Euplotes vannus (Protozoa, Ciliophora) in different artificial seawaters

    Science.gov (United States)

    Xu, Henglong; Zhu, Mingzhuang; Jiang, Yong; Gao, Shan; Min, Gi-Sik; Al-Rasheid, Khaled A. S.

    2011-01-01

    To study population dynamics of marine ciliates in different artificial seawaters (ASW), the population growth dynamics of a common marine ciliate Euplotes vannus were investigated using beef extract media and rice media for five types of ASW and natural seawater (NSW). The results show that: (1) the population growth rate was in the order of NSW>Flack ASW>Nakamula ASW>Schmadz ASW>Oshima ASW>Subow ASW and was considerably higher in rice media than in beef extract media (apart from Subow ASW); (2) the maximum density of E. vannus in stationary phase in each treatment was ranked as Flack ASW>Nakamula ASW>Schmadz ASW>NSW>Oshima ASW>Subow ASW, and was again higher in rice media than in beef extract media (except for Subow ASW); (3) the exponential and stationary phases were longer in rice media than in beef extract media; (4) strains of E. vannus that had been domesticated for >1 year in ASW grew significantly slower, with lower maximum density and longer stationary phase than those isolated and maintained in NSW. It was demonstrated that: (1) E. vannus may grow well in Flack, Nakamula and Schmads ASW compared with NSW (mainly in terms of growth rate); and (2) Oshima ASW is the preferred choice for stock cultures of E. vannus, but the ASWs Flack, Nakamula and Schmadz are preferred for mass culture. These findings suggest that these three ASWs are effective for the cultivation of marine protozoa for experimental studies on ecology, toxicology and molecular biology.

  10. Modeling the distribution of ciliate protozoa in the reticulo-rumen using linear programming.

    Science.gov (United States)

    Hook, S E; Dijkstra, J; Wright, A-D G; McBride, B W; France, J

    2012-01-01

    The flow of ciliate protozoa from the reticulo-rumen is significantly less than expected given the total density of rumen protozoa present. To maintain their numbers in the reticulo-rumen, protozoa can be selectively retained through association with feed particles and the rumen wall. Few mathematical models have been designed to model rumen protozoa in both the free-living and attached phases, and the data used in the models were acquired using classical techniques. It has therefore become necessary to provide an updated model that more accurately represents these microorganisms and incorporates the recent literature on distribution, sequestration, and generation times. This paper represents a novel approach to synthesizing experimental data on rumen microorganisms in a quantitative and structured manner. The development of a linear programming model of rumen protozoa in an approximate steady state will be described and applied to data from healthy ruminants consuming commonly fed diets. In the model, protozoa associated with the liquid phase and protozoa attached to particulate matter or sequestered against the rumen wall are distinguished. Growth, passage, death, and transfer of protozoa between both pools are represented. The results from the model application using the contrasting diets of increased forage content versus increased starch content indicate that the majority of rumen protozoa, 63 to 90%, are found in the attached phase, either attached to feed particles or sequestered on the rumen wall. A slightly greater proportion of protozoa are found in the attached phase in animals fed a hay diet compared with a starch diet. This suggests that experimental protocols that only sample protozoa from the rumen fluid could be significantly underestimating the size of the protozoal population of the rumen. Further data are required on the distribution of ciliate protozoa in the rumen of healthy animals to improve model development, but the model described herein

  11. Ciliate community structure and interactions within the planktonic food web in two alpine lakes of contrasting transparency.

    Science.gov (United States)

    Kammerlander, Barbara; Koinig, Karin A; Rott, Eugen; Sommaruga, Ruben; Tartarotti, Barbara; Trattner, Florian; Sonntag, Bettina

    2016-11-01

    Climate warming is accelerating the retreat of glaciers and recently, many 'new' glacial turbid lakes have been created. In the course of time, the loss of the hydrological connectivity to a glacier causes, however, changes in their water turbidity and turns these ecosystems into clear ones.To understand potential differences in the food-web structure between glacier-fed turbid and clear alpine lakes, we sampled ciliates, phyto-, bacterio- and zooplankton in one clear and one glacial turbid alpine lake, and measured key physicochemical parameters. In particular, we focused on the ciliate community and the potential drivers for their abundance distribution.In both lakes, the zooplankton community was similar and dominated by the copepod Cyclops abyssorum tatricus and rotifers including Polyarthra dolichoptera, Keratella hiemalis, Keratella cochlearis and Notholca squamula. The phytoplankton community structure differed and it was dominated by the planktonic diatom Fragilaria tenera and the cryptophyte alga Plagioselmis nannoplanctica in the glacial turbid lake, while chrysophytes and dinoflagellates were predominant in the clear one.Ciliate abundance and richness were higher in the glacial turbid lake (∼4000-27 800 Ind L(-1), up to 29 species) than in the clear lake (∼570-7150 Ind L(-1), up to eight species). The dominant species were Balanion planctonicum, Askenasia cf. chlorelligera, Urotricha cf. furcata and Mesodinium cf. acarus. The same species dominated in both lakes, except for Mesodinium cf. acarus and some particle-associated ciliates, which occurred exclusively in the glacial turbid lake. The relative underwater solar irradiance (i.e. percentage of PAR and UVR at depth) significantly explained their abundance distribution pattern, especially in the clear water lake. In the glacial turbid lake, the abundance of the dominating ciliate taxa was mainly explained by the presence of predatory zooplankton.Our results revealed an unexpected high

  12. Primers to block the amplification of symbiotic apostome ciliate 18S rRNA gene in a PCR-based copepod diet study

    Science.gov (United States)

    Yi, Xiaoyan; Zhang, Huan; Liu, Guangxing

    2014-05-01

    Pelagic copepods play an important role in the marine food web. However, a full understanding of the ecological status of this zooplankton group depends on the careful study of their natural diets. In previous PCR-based copepod diet studies, we found many apostome ciliates that live symbiotically under the exoskeleton of the copepods, and their sequences were often over-represented in the 18S rRNA gene (18S rDNA) libraries. As a first step to address this issue, we designed three apostome ciliate 18S rDNA blocking primers, and tested their blocking efficiency against apostome ciliate 18s rDNA under various PCR conditions. Using a semi-quantitative PCR method, we optimized the conditions to efficiently amplify the 18S rDNA of the prey while simultaneously excluding the symbiotic apostome ciliates. This technique will facilitate PCR-based diet studies of copepods and other zooplankton in their natural environments.

  13. Structure and seasonal dynamics of the protozoan community (heterotrophic flagellates, ciliates, amoeboid protozoa) in the plankton of a large river (River Danube, Hungary).

    Science.gov (United States)

    Kiss, Aron Keve; Acs, Eva; Kiss, Keve Tihamér; Török, Júlia Katalin

    2009-05-01

    Seasonal dynamics of all major protozoan groups were investigated in the plankton of the River Danube, upstream of Budapest (Hungary), by bi-weekly sampling over a 1-year long period. Sixty-one heterotrophic flagellate, 14 naked amoeba, 50 testate amoeba, 4 heliozoan and 83 ciliate morphospecies were identified. The estimated abundance ranges of major groups throughout the year were as follows: heterotrophic flagellates, 0.27-7.8 x 10(6)ind.l(-1); naked amoebae, max. 3300ind.l(-1); testaceans, max. 1600ind.l(-1); heliozoans, max. 8500ind.l(-1); ciliates, 132-34,000ind.l(-1). In terms of biovolume, heterotrophic flagellates dominated throughout the year (max. 0.58mm(3)l(-1)), and ciliates only exceeded their biovolume in summer (max. 0.76mm(3)l(-1)). Naked amoeba and heliozoan biovolume was about one, and testacean biovolume 1-3, orders of magnitude lower than that of ciliates. In winter, flagellates, mainly chrysomonads, had the highest biomass, whilst ciliates were dominated by peritrichs. In 2005 from April to July a long spring/summer peak occurred for all protozoan groups. Beside chrysomonads typical flagellates were choanoflagellates, bicosoecids and abundant microflagellates (large chrysomonads and Collodictyon). Most abundant ciliates were oligotrichs, while Phascolodon, Urotricha, Vorticella, haptorids, Suctoria, Climacostomum and Stokesia also contributed significantly to biovolume during rapid succession processes. In October and November a second high protozoan peak occurred, with flagellate dominance, and slightly different taxonomic composition.

  14. [Relationship of bacteria of Bacillus genus with ciliate Colpoda steinii and their impact on germination of plant seeds].

    Science.gov (United States)

    Pogorelova, V V; Bega, Z T; Kurdish, I K

    2012-01-01

    Features of symbiotic coexistence of bacteria of the genus Bacillus with ciliates Colpoda steinii have been studied. In their mutual cultivation during 10 days the number of bacteria B. subtilis IMV V-7023 was reduced 4.4 times, B. pumilus 3 - 3.4 times, B. megaterium 12 - 2.5 times. In the mixed culture with B. pumilus 3 the number of the ciliates increased gradualluy while under availability of the other two bacilli strains the number of protozoan increased in the first two days, after that their amount decreased. Treatment of some plants seeds by suspension of B. subtilis IMV V-7023 with the protozoan increased their germination and stimulated the growth of plants at the early stages of development.

  15. Ectopic Ciliated Cyst in the Mandible Secondary to Genioplasty and Lefort after Two Years: A Case Report and Literature Review

    Science.gov (United States)

    Seifi, Safoura; Sohanian, Shabnam; Khakbaz, Oveis; Abesi, Farida; Aliakbarpour, Fatemeh; Rayani, Arezoo

    2016-01-01

    Introduction: The ectopic ciliated cyst is a rare non-odontogenic cyst which occurs as a delayed complication after maxillary sinus radical surgery; this lesion emerges due to the destruction of the sinus mucosa during the surgery and entrapment of the respiratory epithelium in the region. This lesion has been observed in very rare cases following genioplasty and bimaxillary orthognathic surgery. Case Report: We reported a case of the ectopic ciliated cyst in in the mandible of a 37-year-old Iranian woman following genioplasty and Lefort 1 surgery after 2 years. Its treatment was enucleation. Conclusion: Long-term follow-up after cosmetic surgery of both jaws is recommended due to the probability of this cyst. PMID:27738612

  16. Blooms of a benthic ciliate, Maristentor dinoferus (Heterotrichea: Maristentoridae, on coral reefs of Guam, Mariana Islands. (Note

    Directory of Open Access Journals (Sweden)

    Schefter, M.

    2012-05-01

    Full Text Available Maristentor dinoferus is visible in situ with the naked eye; it forms aggregations at several scales: individuals form dynamic clusters within colonies that are normally widely scattered, but in recurrent blooms during the dry seasons of 2005 through 2007, colonies often formed close together in patches (metapopulations. Patches were extremely abundant in Guam, both in Apra Harbor and on the outer coast. This is the first time that long-term changes in a benthic ciliate population have been documented in situ and that multi-scale patchiness has been reported for a benthic ciliate. Colonies were mapped and monitored; some patches over 1 m diameter were recorded. Since 2008, the distribution has again consisted of scattered colonies, as it did from 1999–2004.

  17. The influence of environmental characteristics on the distribution of ciliates (Protozoa, Ciliophora in an urban stream of southeast Brazil

    Directory of Open Access Journals (Sweden)

    RJP. Dias

    Full Text Available The aim of this research was to study the ciliated protozoa community at three sampling stations that receive different levels of domestic sewage along the São Pedro Stream in the municipality of Juiz de Fora, Minas Gerais, Brazil, in order to determine the influence of organic pollution on this community and to assess the feasibility of using ciliates as water quality indicators. Four physical-chemical parameters of the water samples were evaluated: dissolved oxygen concentration, electrical conductivity, pH and temperature. The sediment was obtained manually, using dredges with capacity of 300 mL, at each collection point. Point 1 was located in a rural region that receives a low sewage load, while Points 2 and 3 were located in populated regions receiving high sewage loads. We found 22 ciliate species, of which 18 are included in the saprobic system and are considered bioindicators. These showed beta-mesosaprobic environments at Point 1 and alfa-mesosaprobic to polisaprobic environments at Points 2 and 3. The low levels of dissolved oxygen and the high electrical conductivity values at Points 2 and 3, together with the strong similarity between the ciliate taxocenoses of these points and the weak similarity between Point 1 and the other two, confirm the high sewage loads received at the latter two points. The combination of the biological indicators and physical-chemical analyses therefore proved itself to be an efficient method of evaluating water quality, and has excellent potential to support decisions on the conservation of headwaters and recuperation of degraded environments in lotic systems.

  18. Blooms of a benthic ciliate, Maristentor dinoferus (Heterotrichea: Maristentoridae), on coral reefs of Guam, Mariana Islands. (Note)

    OpenAIRE

    Schefter, M.; Lobban, C.S.

    2012-01-01

    Maristentor dinoferus is visible in situ with the naked eye; it forms aggregations at several scales: individuals form dynamic clusters within colonies that are normally widely scattered, but in recurrent blooms during the dry seasons of 2005 through 2007, colonies often formed close together in patches (metapopulations). Patches were extremely abundant in Guam, both in Apra Harbor and on the outer coast. This is the first time that long-term changes in a benthic ciliate population have been ...

  19. Can the halophilic ciliate Fabrea salina be used as a bio-control of microalgae blooms in solar salterns?

    Science.gov (United States)

    Hong, Hyun Pyo; Choi, Joong Ki

    2015-09-01

    The microlage Dunaliella salina, a major producer in salterns, is a serious problem for salt production. In this study we tried to assess if Fabrea salina can control D. salina. By parameterising numerical and functional response (growth and grazing vs prey abundance, respectively) at 90 psu and 30°C, where the ciliate is abundant and grows well, we developed a predator-prey model. The model is used to explore how change in microalga growth rate affect the dynamics, and the functional response is used in combination with field data to assess the potential impact of F. salina on D. salina. Over the 20 d simulation the ciliate controlled the prey population under all prey growth rates; although once D. salina were exhausted below the threshold level, F. salina died due to starvation, allowing the alga to increase in abundance, resulting in one or two predatorprey cycle, depending on prey growth rate. In general, the model predicted trends observed by others in the field, suggesting that it provided a good prediction of what may occur under the conditions we examined. Likewise we show that the ciliate can have a high impact on microalgal populations in the field. Finally, a literature review indicated that F. salina could be a good competitor with other protozoa and metazoan in salterns, depending on salinity and temperature, which requires further study and attention. In summary, we encourage continued studies on this unique ciliate on solar salterns and suggest that it may be useful in the bio-control of micoalgae.

  20. Determination of trace elements in freshwater rotifers and ciliates by total reflection X-ray fluorescence spectrometry

    Science.gov (United States)

    Woelfl, S.; Óvári, M.; Nimptsch, J.; Neu, T. R.; Mages, M.

    2016-02-01

    Element determination in plankton is important for the assessment of metal contamination of aquatic environments. Until recently, it has been difficult to determine elemental content in rotifers or ciliates derived from natural plankton samples because of the difficulty in handling and separation of these fragile organisms. The aim of this study was to evaluate methods for separation of rotifers and large ciliates from natural plankton samples (μg range dry weight) and subsequent analysis of their elemental content using total-reflection X-ray fluorescence spectrometry (TXRF). Plankton samples were collected from different aquatic environments (three lakes, one river) in Chile, Argentina and Hungary. From one to eighty specimens of five rotifer species (Brachionus calyciflorus, Brachionus falcatus, Asplanchna sieboldii, Asplanchna sp., Philodina sp.) and four to twelve specimens of one large ciliate (Stentor amethystinus) were prepared according to the dry method originally developed for microcrustaceans, and analysed by TRXF following in situ microdigestion. Our results demonstrated that it possible to process these small and fragile organisms (individual dry mass: 0.17-9.39 μg ind- 1) via careful washing and preparation procedures. We found species-dependent differences of the element mass fractions for some of the elements studied (Cr, Mn, Fe, Ni, Cu, Zn, As, Pb), especially for Cu, Fe and Mn. One large rotifer species (A. sieboldii) also showed a negative correlation between individual dry weight and the element content for Pb, Ni and Cr. We conclude that our application of the in situ microdigestion-TRXF method is suitable even for rotifers and ciliates, greatly expanding the possibilities for use of plankton in biomonitoring of metal contamination in aquatic environments.

  1. Ecological functions of ciliated protozoa in marine ecosystem: effects of ammonium on the population growth of Euplotes vannus

    Institute of Scientific and Technical Information of China (English)

    Xu Henglong; Song Weibo; Zhu Mingzhuang; Wang Mei; Ma Honggang; Xu Xiaozhong

    2005-01-01

    The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method. It is showed that ammonium exerts inhibitory effects on the growth of the ciliate populations in a concentration-dependent way. Statistical analysis reveals that the population growth dynamics exposed to ammonium-N concentration over 100mg/L are significantly different from that in the control at P<0.05 level. Linear regression determined that the 24h, 36h, 48h, 60h, 72h and 84h IC50 values of ammonium-N are 19.68, 201.51, 167.49, 47.86, 50.43 and 43.11 concentration over 100mg/L, respectively (P<0.05; pH 8.2; salinity 28 ppt; temperature, 25℃). The results indicate that the tolerance to ammonium in E. vannus is considerably higher than that of the larvae or juveniles of some metozoa, such as cultured prawns and oysters. Therefore, it is believed that the high tolerance to ammonium is necessary for ciliated protozoa to play positive roles in maintaining and improving water quality in marine ecosystems, especially in the intensive aquaculture waters with high-level ammonium. In addition, the correlation between IC50 values and exposure time was discussed.

  2. Acute toxicities of potassium permanganate, formalin, and Lugol's iodine solution to a marine ciliate, Pleuronema coronatum (ciliophora, scuticociliatida)

    Science.gov (United States)

    Yantao, Qiu; Weibo, Song

    2002-10-01

    Acute toxicities of potassium permanganate, formalin, and Lugol’s iodine solution to a commonly occurred marine ciliate Pleuronema coronatum (Ciliophora, Scuticociliatida) were measured. Linear regression analysis of the results highlighted the close relationships between doses of the medicines and mortalities of the organisms, thus providing a capability to predict toxicity effects from the dose. Toxic effects of the medicines on the ciliates were described in the present paper, and the median lethal concentrations (LC50 values) were given. Results of measurements indicated that 2 h-LC50 and 12 h-LC50 values of formalin on P. coronatum were 59.00×10-6 and 43.57×10-6, while those of Lugol’s solutions were 90.13 and 67.84×10-6 respectively. The tolerance of P. coronatum to formalin is apparently lower than that to Lugol’s iodine solution and potassium permanganate is a suitable medicine to kill ciliates in short time.

  3. Acute Toxicities of Potassium Permanganate, Formalin, and Lugol's Iodine Solution to a Marine Ciliate,Pleuronema coronatum ( Ciliophora, Scuticociliatida)

    Institute of Scientific and Technical Information of China (English)

    QIU Yantao; SONG Weibo

    2002-01-01

    Acute toxicities of potassium permanganate, formalin, and Lugol's iodine solution to a commonly occurred ma-rine ciliate Pleuronema coronatum (Ciliophora, Scuticociliatida) were measured. Linear regression analysis of the resultshighlighted the close relationships between doses of the medicines and mortalities of the organisms, thus providing a capabili-ty to predict toxicity effects from the dose. Toxic effects of the medicines on the ciliates were described in the present paper,and the median lethal concentrations (LC50 values) were given. Results of measurements indicated that 2 h-LC50 and 12 h-LC50 values of formalin on P. coronatum were 59.00 × 10-6 and 43.57 × 10 6, while those of Lugol's solutions were 90.13 and67.84 × 10 6 respectively. The tolerance of P. coronatum to formalin is apparently lower than that to Lugol' s iodine solutionand potassium permanganate is a suitable medicine to kill ciliates in short time.

  4. The water-borne protein signals (pheromones) of the Antarctic ciliated protozoan Euplotes nobilii: structure of the gene coding for the En-6 pheromone.

    Science.gov (United States)

    La Terza, Antonietta; Dobri, Nicoleta; Alimenti, Claudio; Vallesi, Adriana; Luporini, Pierangelo

    2009-01-01

    The marine Antarctic ciliate, Euplotes nobilii, secretes a family of water-borne signal proteins, denoted as pheromones, which control vegetative proliferation and mating in the cell. Based on the knowledge of the amino acid sequences of a set of these pheromones isolated from the culture supernatant of wild-type strains, we designed probes to identify their encoding genes in the cell somatic nucleus (macronucleus). The full-length gene of the pheromone En-6 was determined and found to contain an open-reading frame specific for the synthesis of the En-6 cytoplasmic precursor (pre-pro-En-6), which requires 2 proteolytic cleavages to remove the signal peptide (pre) and the prosegment before secretion of the mature protein. In contrast to the sequence variability that distinguishes the secreted pheromones, the pre- and pro-sequences appear to be tightly conserved and useful for the construction of probes to clone every other E. nobilii pheromone gene. Potential intron sequences in the coding region of the En-6 gene imply the synthesis of more En-6 isoforms.

  5. Expression of innate immune complement regulators on brain epithelial cells during human bacterial meningitis

    Directory of Open Access Journals (Sweden)

    Gasque Philippe

    2006-09-01

    Full Text Available Abstract Background In meningitis, the cerebrospinal fluid contains high levels of innate immune molecules (e.g. complement which are essential to ward off the infectious challenge and to promote the infiltration of phagocytes (neutrophils, monocytes. However, epithelial cells of either the ependymal layer, one of the established niche for adult neural stem cells, or of the choroid plexus may be extremely vulnerable to bystander attack by cytotoxic and cytolytic complement components. Methods In this study, we assessed the capacity of brain epithelial cells to express membrane-bound complement regulators (ie, CD35, CD46, CD55 and CD59 in vitro and in situ by immunostaining of control and meningitis human brain tissue sections. Results Double immunofluorescence experiments for ependymal cell markers (GFAP, S100, ZO-1, E-cadherin and complement regulators indicated that the human ependymal cell line model was strongly positive for CD55, CD59 compared to weak stainings for CD46 and CD35. In tissues, we found that CD55 was weakly expressed in control choroid plexus and ependyma but was abundantly expressed in meningitis. Anti-CD59 stained both epithelia in apical location while increased CD59 staining was solely demonstrated in inflamed choroid plexus. CD46 and CD35 were not detected in control tissue sections. Conversely, in meningitis, the ependyma, subependyma and choroid plexus epithelia were strongly stained for CD46 and CD35. Conclusion This study delineates for the first time the capacity of brain ependymal and epithelial cells to respond to and possibly sustain the innate complement-mediated inflammatory insult.

  6. Ku-mediated coupling of DNA cleavage and repair during programmed genome rearrangements in the ciliate Paramecium tetraurelia.

    Directory of Open Access Journals (Sweden)

    Antoine Marmignon

    2014-08-01

    Full Text Available During somatic differentiation, physiological DNA double-strand breaks (DSB can drive programmed genome rearrangements (PGR, during which DSB repair pathways are mobilized to safeguard genome integrity. Because of their unique nuclear dimorphism, ciliates are powerful unicellular eukaryotic models to study the mechanisms involved in PGR. At each sexual cycle, the germline nucleus is transmitted to the progeny, but the somatic nucleus, essential for gene expression, is destroyed and a new somatic nucleus differentiates from a copy of the germline nucleus. In Paramecium tetraurelia, the development of the somatic nucleus involves massive PGR, including the precise elimination of at least 45,000 germline sequences (Internal Eliminated Sequences, IES. IES excision proceeds through a cut-and-close mechanism: a domesticated transposase, PiggyMac, is essential for DNA cleavage, and DSB repair at excision sites involves the Ligase IV, a specific component of the non-homologous end-joining (NHEJ pathway. At the genome-wide level, a huge number of programmed DSBs must be repaired during this process to allow the assembly of functional somatic chromosomes. To understand how DNA cleavage and DSB repair are coordinated during PGR, we have focused on Ku, the earliest actor of NHEJ-mediated repair. Two Ku70 and three Ku80 paralogs are encoded in the genome of P. tetraurelia: Ku70a and Ku80c are produced during sexual processes and localize specifically in the developing new somatic nucleus. Using RNA interference, we show that the development-specific Ku70/Ku80c heterodimer is essential for the recovery of a functional somatic nucleus. Strikingly, at the molecular level, PiggyMac-dependent DNA cleavage is abolished at IES boundaries in cells depleted for Ku80c, resulting in IES retention in the somatic genome. PiggyMac and Ku70a/Ku80c co-purify as a complex when overproduced in a heterologous system. We conclude that Ku has been integrated in the Paramecium

  7. Ku-mediated coupling of DNA cleavage and repair during programmed genome rearrangements in the ciliate Paramecium tetraurelia.

    Science.gov (United States)

    Marmignon, Antoine; Bischerour, Julien; Silve, Aude; Fojcik, Clémentine; Dubois, Emeline; Arnaiz, Olivier; Kapusta, Aurélie; Malinsky, Sophie; Bétermier, Mireille

    2014-08-01

    During somatic differentiation, physiological DNA double-strand breaks (DSB) can drive programmed genome rearrangements (PGR), during which DSB repair pathways are mobilized to safeguard genome integrity. Because of their unique nuclear dimorphism, ciliates are powerful unicellular eukaryotic models to study the mechanisms involved in PGR. At each sexual cycle, the germline nucleus is transmitted to the progeny, but the somatic nucleus, essential for gene expression, is destroyed and a new somatic nucleus differentiates from a copy of the germline nucleus. In Paramecium tetraurelia, the development of the somatic nucleus involves massive PGR, including the precise elimination of at least 45,000 germline sequences (Internal Eliminated Sequences, IES). IES excision proceeds through a cut-and-close mechanism: a domesticated transposase, PiggyMac, is essential for DNA cleavage, and DSB repair at excision sites involves the Ligase IV, a specific component of the non-homologous end-joining (NHEJ) pathway. At the genome-wide level, a huge number of programmed DSBs must be repaired during this process to allow the assembly of functional somatic chromosomes. To understand how DNA cleavage and DSB repair are coordinated during PGR, we have focused on Ku, the earliest actor of NHEJ-mediated repair. Two Ku70 and three Ku80 paralogs are encoded in the genome of P. tetraurelia: Ku70a and Ku80c are produced during sexual processes and localize specifically in the developing new somatic nucleus. Using RNA interference, we show that the development-specific Ku70/Ku80c heterodimer is essential for the recovery of a functional somatic nucleus. Strikingly, at the molecular level, PiggyMac-dependent DNA cleavage is abolished at IES boundaries in cells depleted for Ku80c, resulting in IES retention in the somatic genome. PiggyMac and Ku70a/Ku80c co-purify as a complex when overproduced in a heterologous system. We conclude that Ku has been integrated in the Paramecium DNA cleavage

  8. Electrochemical study of the interaction between Eu{sup 3+} and ciliate Euplotes octocarinatus centrin

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Baojuan; Wang Ziwei [Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan 030006 (China); Tian Yanni, E-mail: tianyann@sxu.edu.c [Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan 030006 (China); Wang Zhijun [Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan 030006 (China); Yang Binsheng, E-mail: yangbs@sxu.edu.c [Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan 030006 (China)

    2010-05-01

    A new species was formed when protein P{sub 23} (one segment of ciliate Euplotes octocarinatus centrin) was added to a solution of Eu{sup 3+}. The interaction between P{sub 23} and Eu{sup 3+} was investigated by cyclic voltammetry, pulse voltammetry and electrochemical impedance spectroscopy in 10 mM N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid (HEPES) buffer (pH 7.4) using a pyrolytic graphite electrode. The formal potential (E{sup o}') of Eu{sup 3+} shifted from -0.61 to -0.84 V (versus saturated calomel electrode) after P{sub 23} was added to the Eu{sup 3+} solution. The diffusion coefficient (D), the charge-transfer coefficient (alpha) and the electron transfer standard rate constant (k{sub s}) were obtained in the absence and the presence of P{sub 23}. The affinity constant of Eu{sup 3+} and P{sub 23} was determined to be (1.89 +- 0.51) x 10{sup 4} M{sup -1}. The electrochemical investigation of europium bound to the protein provided useful data for the studies of calcium-binding proteins.

  9. Purification and partial characterization of glyceraldehyde-3-phosphate dehydrogenase from the ciliate Tetrahymena thermophila

    Institute of Scientific and Technical Information of China (English)

    Nadia Errafiy; Abdelaziz Soukri

    2012-01-01

    In the present study,we purified the glycolytic enzymeglyceraldehyde-3-phosphate dehydrogenase (GAPDH)which is involved in cellular energy production and has important housekeeping functions,from the ciliate Tetrahymena thermophila using a three-step procedure.The enzyme was purified ~68 folds by ammonium sulfate precipitation,followed by two steps of column chromatography (DEAE-cellulose and Mono-S).The purified enzyme is a homotetramer with a molecular weight of ~120 kDa.Isoelectric focusing analysis showed the presence of only one basic GAPDH isoform with an isoelectric point of 8.8.Western blot analysis showed a single 32-kDa band corresponding to the enzyme subunit using a monospecific polyclonal antibody against the T.thermophila GAPDH.The maximum of enzyme activity occurred at pH 8.0 and at 30-35℃.The apparent Km values for both NAD+ and D-glyceraldehyde-3-phosphate were 0.102±0.012 and 0.360 + 0.018 mM,respectively.The maximal velocity (Vmax) was 39.40 + 2.95 U/mg.The T.thermophila GAPDH is inhibited by oxidative and nitrosative stress reagents.

  10. Molecular Phylogeny of Mobilid and Sessilid Ciliates Symbiotic in Eastern Pacific Limpets (Mollusca: Patellogastropoda).

    Science.gov (United States)

    Irwin, Nicholas A T; Lynn, Denis H

    2015-01-01

    The phylogenetic relationships of the ciliate subclass Peritrichia, composed of the orders Mobilida and Sessilida, have recently come under debate as morphological and molecular analyses have struck contrasting conclusions as to the monophyly of the group. We provide additional molecular data to assess the monophyly of the Peritrichia by sequencing the small subunit ribosomal RNA genes of two symbiotic peritrichs, Urceolaria korschelti and Scyphidia ubiquita, found inhabiting the mantle cavity of limpets. Although phylogenetic analyses indicated a nonmonophyletic Peritrichia, approximately unbiased tests revealed that the monophyletic hypothesis could not be rejected. With regard to the Mobilida, our analysis showed divergence within the family Trichodinidae related to host taxa-a molluscan clade and a fish clade. For the Sessilida, the family Scyphidiidae was sister to the Astylozoidae. In our sampling of U. korschelti and S. ubiquita, both species showed significant genetic divergence among geographically isolated, yet morphologically indistinguishable populations. We hypothesize that cryptic speciation has produced these morphologically identical species and argue that more extensive genomic analyses are required to fully assess the monophyly, biogeography, and ultimately biodiversity of the peritrichs.

  11. Adaptation responses of individuals to environmental changes in the ciliate Euplotes crassus

    Science.gov (United States)

    Kim, Se-Joo; Kim, Jin-Hyoung; Ju, Se-Jong

    2017-03-01

    Although the response unit of living organisms to environmental changes is at the individual level, most experiments on the adaptation responses of ciliates have been conducted in batches, comprising multiple-individuals, due to their microscopic size. However, here, we confirmed that individuals undergo different division cycles in monocultures of Euplotes crassus. They also exhibited transcript variations of 4.63-fold in SSU and of 22.78- fold in Hsp70. Additionally, in salt-stressed E. crassus individuals, SSU transcripts of individuals varied by 6.92-fold at 27 psu, 8.69- fold at 32 psu, and 2.51-fold at 37 psu. However, the maximum difference in Hsp70 was only 4.23-fold under all conditions. These results suggest there may be different biological rhythms even in siblings derived from the same parent. It can also be inferred that various environmental factors have different effects on different E. crassus individuals. Therefore, to elucidate relationships between organism adaptations and environmental changes, studies at the individual level should be conducted with multi-individual approaches.

  12. Studies on the in vitro cultivation of ciliate protozoa from the kangaroo forestomach.

    Science.gov (United States)

    Dehority, Burk A; Wright, André-Denis G

    2014-08-01

    The methods used for culturing rumen protozoa were found to be unsatisfactory for growth of ciliate protozoa from the kangaroo forestomach. Based on published measurements of physical parameters in the marsupial forestomach, several modifications were incorporated into the procedure, i.e., an increase in % hydrogen in the gas phase, adjustment of initial pH of the medium to 6.9-7.0 range, feed only forage as a substrate and incubate at a lower temperature (33-36 °C). Only incubation at the lower temperature increased survival time of the kangaroo protozoa. Two species of Bitricha were still viable after 28 d in culture. Cultures had to be terminated at that time. One of the species differed considerably in size and shape from previously described species and based on 18S rRNA data, may represent a new species of Bitricha. The second species, present in low numbers was identified as Bitricha oblata. In a separate trial, Macropodinium yalanbense survived for 11 d, at which time these cultures also had to be terminated.

  13. Trichodina modesta: an exotic ciliate in the Neotropical region parasitizing an unusual host

    Directory of Open Access Journals (Sweden)

    Gustavo Moraes Ramos Valladão

    Full Text Available In this study, an important ornamental fish, Betta splendens (Osphronemidae, from three different Brazilian states was examined for parasitic infestations. Smears with parasites were impregnated with silver nitrate or stained using Giemsa for taxonomic evaluation. A disc-shaped trichodinid with a body diameter of 39.7 ± 3.3 µm, adhesive disc diameter of 32.9 ± 3.1 µm and denticulate ring diameter of 19.5 ± 2.0 µm was found. The morphological characteristics resembled those of Trichodina modesta Lom, 1970, a species that shows clear host specificity for Cypriniformes. Until now, its occurrence was restricted to the Eurasian region. In the present study, a new host for T. modesta is reported and therefore the first occurrence of this species in the Americas. The parasite was possibly introduced into the Neotropical region through the exotic fish trade, especially of Cypriniformes used by aquarists. The distribution of this ciliate is discussed and a checklist of localities and hosts for the species is provided.

  14. Distribution and Abundance of Interstitial Ciliates in Southampton Water in Relation to Physicochemical Conditions, Metal Pollution and the Availability of Food Organisms

    Science.gov (United States)

    Al-Rasheid, K. A. S.; Sleigh, M. A.

    1995-07-01

    Sediment samples were collected at low tide from eight sandy and muddy shores around Southampton Water on one occasion in July and one occasion in September. The temperature and pH of the sediments were measured at the time of collection, the water content of the sediments was determined and samples subjected to granulometric analysis. The population densities of bacteria and microflagellates were determined and the ciliates in sub-samples were identified to genus level and enumerated. The concentrations of cadmium, copper, lead, mercury and nickel in the interstitial water and in the dried sediments were measured by the dithizone and atomic absorption methods, respectively. These metal concentrations were compared with literature values for other British estuaries. Ciliates belonging to 23 genera were found in the sediments, the diversity of ciliates varying widely between stations. Bacterial numbers (mean ˜5×10 8 cm -3) at the various stations correlate with the surface area of the sediment particles and also correlate weakly with flagellate numbers (mean ˜2×10 4 cm -3). Total ciliate numbers (mean ˜1×10 3 cm -3) correlated quite strongly with flagellate numbers, but not with bacterial numbers. Euplotes, Strombidiumand Uronemawere common at all stations and generally dominated; Didinium, Mesodinium pulexand Pleuronemawere also found at all stations, and the latter two were often numerous; Uronychiawas found at seven stations. The distributions of Acinetopsis, Blepharisma, Lacrymaria, M. pulex, Paramecium, Spirostomum, Strombidiumand Vorticellashowed similar correlations to one another, and tended to favour sites nearer to sources of freshwater; these ciliates also showed a correlation with pH, river waters locally being alkaline. None of the ciliates showed correlations with any physical characteristics of the sediments. There were no negative correlations of ciliate distributions with metal pollutants. The levels of metal pollutants found in water drained

  15. Description of the rare marine ciliate, Uronychia multicirrus song, 1997 (Ciliophora; Euplotida) based on morphology, morphogenesis and SS rRNA gene sequence.

    Science.gov (United States)

    Shen, Zhuo; Shao, Chen; Gao, Shan; Lin, Xiaofeng; Li, Jiqiu; Hu, Xiaozhong; Song, Weibo

    2009-01-01

    A population of the marine euplotid ciliate, Uronychia multicirrus Song 1997, found in the littoral zone of the Daya Bay, Guangdong, South China, was investigated using live observation and protargol impregnation method. This species is diagnosed by possessing a long row of ventral cirri, which has never been seen in all other known congeners. Divisional process, described based on protargol-impregnated specimens, is typical of the genus regarding its general pattern: (1) the oral primordia in both proter and opisthe develop de novo in two subcortical pouches, while the UM-anlage forms de novo (i.e. does not develop from the oral primordium); (2) five frontoventral-transverse (FVT)-cirral anlagen develop in a primary-mode on the cell surface, and almost all the cirri are derived from the FVT-anlagen, except the first frontal cirri, which are formed de novo in both dividers; (3) the species characteristic ventral row derives from the right-most FVT-anlage; (4) the parental structures do not take part in the construction of the marginal anlagen, and (5) the caudal cirri originate in the right-most two dorsal kineties in a multi-segmentation mode. The small subunit rRNA gene of U. multicirrus (GenBank accession number: EU267929) is 1,773 bp and differs by 0.9-1.41% from its closely related congeners.

  16. Morphology, morphogenesis and small subunit rRNA gene sequence of a soil hypotrichous ciliate, Perisincirra paucicirrata (Ciliophora, Kahliellidae), from the shoreline of the Yellow River, North China.

    Science.gov (United States)

    Li, Fengchao; Xing, Yi; Li, Jiamei; Al-Rasheid, Khaled A S; He, Songke; Shao, Chen

    2013-01-01

    The morphology, morphogenesis, and 18S rRNA gene sequence of a soil hypotrichous ciliate Perisincirra paucicirrata, isolated from north China, were investigated. Perisincirra paucicirrata differs from its congeners in: (1) having a body length to width ratio in vivo of 4:1, (2) its adoral zone occupying between 15% and 25% of the total body length, and (3) the presence of two parabuccal cirri, three left (with 10-16 cirri each) and two right marginal rows (with 14-24 cirri each), and three dorsal kineties. Our study offers a first attempt to begin to map the morphogenetic processes of the genus, which are mainly characterised by the following: the formation of four frontal ventral transverse anlagens for each daughter cell, with the proter's anlage I originating from the reorganised anterior part of the parental paroral; the paroral and endoral anlage developed from the reorganised old endoral and do not contribute the first frontal cirrus; the frontoventral transverse anlage I contributing the left frontal cirrus; anlage II generating the middle frontal and the buccal cirri; anlage III developing the right frontal cirrus and the anterior parabuccal cirrus; and anlage IV contributing the posterior parabuccal cirrus. As an additional contribution, we judge that the inner one or the two right rows of P. kahli and P. longicirrata are marginal rows. Phylogenetic analysis based on SSU rDNA sequences suggests that Perisincirra is related to sporadotrichids, but provides no credible evidence for its taxonomic position.

  17. Morphology and SSU rDNA sequence analysis of two hypotrichous ciliates (Protozoa, Ciliophora, Hypotrichia) including the new species Metaurostylopsis parastruederkypkeae n. sp.

    Science.gov (United States)

    Lu, Borong; Wang, Chundi; Huang, Jie; Shi, Yuhong; Chen, Xiangrui

    2016-10-01

    The morphology and phylogeny of two hypotrichous ciliates, Metaurostylopsis parastruederkypkeae n. sp. and Neourostylopsis flavicana (Wang et al., 2011) Chen et al., 2013 were investigated based on morphology, infraciliature and the small subunit (SSU) ribosomal RNA gene (rRNA) sequence. The new species, M. parastruederkypkeae n. sp. was identified according to its characteristics: body shape ellipsoidal, size about (165-200) × (45-60) μm in vivo, cell color reddish; two types of cortical granules including wheat grain-like and yellow-greenish larger ones along the marginal cirri rows and dorsal kineties and dot-like and reddish smaller ones, grouped around marginal cirri on ventral side and arranged in short lines on dorsal side; 26-41 adoral membranelles; three frontal and one parabuccal, five to seven frontoterminal, one buccal, and three to six transverse cirri; seven to thirteen midventral pairs; five to nine unpaired ventral cirri, five to seven left and three to five right marginal rows; and three complete dorsal kineties. Phylogenetic analysis based on SSU rDNA sequences showed that both Metaurostylopsis and Neourostylopsis are monophyletic. As the internal relationship between and within both genera are not clear, further studies on the species in these two genera are necessary. The key characteristics of all known twelve Metaurostylopsis-Apourostylopsis-Neourostylopsis species complex were updated.

  18. Characterization of rumen ciliate community composition in domestic sheep, deer, and cattle, feeding on varying diets, by means of PCR-DGGE and clone libraries.

    Science.gov (United States)

    Kittelmann, Sandra; Janssen, Peter H

    2011-03-01

    The structure and variability of ciliate protozoal communities in the rumens of domestic New Zealand ruminants feeding on different diets was investigated. The relative abundance of ciliates compared with bacteria was similar across all samples. However, molecular fingerprinting of communities showed ruminant-specific differences in species composition. Community compositions of cattle were significantly influenced by diet. In contrast, diet effects in deer and sheep were weaker than the animal-to-animal variation. Cloning and sequencing of almost-full-length 18S rRNA genes from representative samples revealed that New Zealand ruminants were colonized by at least nine genera of ciliates and allowed the assignment of samples to two distinct community types. Cattle contained A-type communities, with most sequences closely related to those of the genera Polyplastron and Ostracodinium. Deer and sheep (with one exception) harboured B-type communities, with the majority of sequences belonging to the genera Epidinium and Eudiplodinium. It has been suggested that species composition of ciliate communities may impact methane formation in ruminants, with the B-type producing more methane. Therefore, manipulation of ciliate communities may be a means of mitigating methane emissions from grazing sheep and deer in New Zealand.

  19. Gene expression in a paleopolyploid: a transcriptome resource for the ciliate Paramecium tetraurelia

    Directory of Open Access Journals (Sweden)

    Kapusta Aurélie

    2010-10-01

    Full Text Available Abstract Background The genome of Paramecium tetraurelia, a unicellular model that belongs to the ciliate phylum, has been shaped by at least 3 successive whole genome duplications (WGD. These dramatic events, which have also been documented in plants, animals and fungi, are resolved over evolutionary time by the loss of one duplicate for the majority of genes. Thanks to a low rate of large scale genome rearrangement in Paramecium, an unprecedented large number of gene duplicates of different ages have been identified, making this organism an outstanding model to investigate the evolutionary consequences of polyploidization. The most recent WGD, with 51% of pre-duplication genes still in 2 copies, provides a snapshot of a phase of rapid gene loss that is not accessible in more ancient polyploids such as yeast. Results We designed a custom oligonucleotide microarray platform for P. tetraurelia genome-wide expression profiling and used the platform to measure gene expression during 1 the sexual cycle of autogamy, 2 growth of new cilia in response to deciliation and 3 biogenesis of secretory granules after massive exocytosis. Genes that are differentially expressed during these time course experiments have expression patterns consistent with a very low rate of subfunctionalization (partition of ancestral functions between duplicated genes in particular since the most recent polyploidization event. Conclusions A public transcriptome resource is now available for Paramecium tetraurelia. The resource has been integrated into the ParameciumDB model organism database, providing searchable access to the data. The microarray platform, freely available through NimbleGen Systems, provides a robust, cost-effective approach for genome-wide expression profiling in P. tetraurelia. The expression data support previous studies showing that at short evolutionary times after a whole genome duplication, gene dosage balance constraints and not functional change are

  20. Generation and analysis of expressed sequence tags from the ciliate protozoan parasite Ichthyophthirius multifiliis

    Directory of Open Access Journals (Sweden)

    Arias Covadonga

    2007-06-01

    Full Text Available Abstract Background The ciliate protozoan Ichthyophthirius multifiliis (Ich is an important parasite of freshwater fish that causes 'white spot disease' leading to significant losses. A genomic resource for large-scale studies of this parasite has been lacking. To study gene expression involved in Ich pathogenesis and virulence, our goal was to generate expressed sequence tags (ESTs for the development of a powerful microarray platform for the analysis of global gene expression in this species. Here, we initiated a project to sequence and analyze over 10,000 ESTs. Results We sequenced 10,368 EST clones using a normalized cDNA library made from pooled samples of the trophont, tomont, and theront life-cycle stages, and generated 9,769 sequences (94.2% success rate. Post-sequencing processing led to 8,432 high quality sequences. Clustering analysis of these ESTs allowed identification of 4,706 unique sequences containing 976 contigs and 3,730 singletons. These unique sequences represent over two million base pairs (~10% of Plasmodium falciparum genome, a phylogenetically related protozoan. BLASTX searches produced 2,518 significant (E-value -5 hits and further Gene Ontology (GO analysis annotated 1,008 of these genes. The ESTs were analyzed comparatively against the genomes of the related protozoa Tetrahymena thermophila and P. falciparum, allowing putative identification of additional genes. All the EST sequences were deposited by dbEST in GenBank (GenBank: EG957858–EG966289. Gene discovery and annotations are presented and discussed. Conclusion This set of ESTs represents a significant proportion of the Ich transcriptome, and provides a material basis for the development of microarrays useful for gene expression studies concerning Ich development, pathogenesis, and virulence.

  1. Preliminary insights into the impact of dietary starch on the ciliate, Neobalantidium coli, in captive chimpanzees.

    Directory of Open Access Journals (Sweden)

    Kateřina Schovancová

    Full Text Available Infections caused by the intestinal ciliate Neobalantidium coli are asymptomatic in most hosts. In humans and captive African great apes clinical infections occasionally occur, manifested mainly by dysentery; however, factors responsible for development of clinical balantidiasis have not been fully clarified. We studied the effect of dietary starch on the intensities of infection by N. coli in two groups of captive chimpanzees. Adult chimpanzees infected by N. coli from the Hodonín Zoo and from the Brno Zoo, Czech Republic, were fed with a high starch diet (HSD (average 14.7% of starch for 14 days, followed by a five-day transition period and subsequently with a period of low starch diet (LoSD (average 0.1% of starch for another 14 days. We collected fecal samples during the last seven days of HSD and LoSD and fixed them in 10% formalin. We quantified trophozoites of N. coli using the FLOTAC method. The numbers of N. coli trophozoites were higher during the HSD (mean ± SD: 49.0 ± 134.7 than during the LoSD (3.5 ± 6.8. A generalized linear mixed-effects model revealed significantly lower numbers of the N. coli trophozoites in the feces during the LoSD period in comparison to the HSD period (treatment contrast LoSD vs. HSD: 2.7 ± 0.06 (SE, z = 47.7; p<<0.001. We conclude that our data provide a first indication that starch-rich diet might be responsible for high intensities of infection of N. coli in captive individuals and might predispose them for clinically manifested balantidiasis. We discuss the potential nutritional modifications to host diets that can be implemented in part to control N. coli infections.

  2. Effect of the nature of energy and nitrogen sources on the population of ciliates in the rumen of sheep

    Directory of Open Access Journals (Sweden)

    Houcine Selmi,

    2011-01-01

    Full Text Available The effect of the nature of raw materials in concentrate on the population of ciliated protozoa was evaluated in the rumen of Sicilo-Sarde sheep. Four rams with permanent rumen canulas, 4.8 ± 0.5 years with an average live weight of 45.25 ± 3.5 kg were used. Rams were fed a common base ration of hay oats (1.5 kg DM/ head/day. Animals were supplemented with 500g/head/day of one of four iso-energetic and iso-proteic concentrates. The four concentrates were: A concentrate (10% barley, 43.3% corn, 25% wheat bran, 17.7% soybean meal and 4% CMV, B concentrate (71.5% barley, 17.5% horse bean, soybean meal, 7% and 4% CMV, C concentrate (66% white sorghum, 30% fava, 4% CMV and D concentrate (71% triticale, 18% horse bean, soybean meal, 7%, 4% CMV. The determination of ciliates was performed on unfiltered rumen fluid, collected two hours after the morning meal. The enumeration of protozoa and determination of various genuses were carried out with a HAWSKLEY counting room after several dilutions, using a microscope. The population of ciliates for, the concentrate B was significantly higher (P<0.05 than those for A, C and D concentrates while different genus of these protozoa were comparable among diets. It can be concluded from this study that the use of local resources in the diet of sheep increased micro organisms in the rumen.

  3. Role of essential lipids in copepod nutrition: no evidence for trophic upgrading of food quality by a marine ciliate

    DEFF Research Database (Denmark)

    Klein Breteler, W.; Koski, Marja; Rampen, S.

    2004-01-01

    copepod species consumed S. sulcatum at significant rates, but after 3 d, weight-specific ingestion decreased more than 2-fold. Larvae and copepodites feeding on S. sulcatum developed at suboptimal rates, survived poorly and showed abnormal morphology in comparison to control individuals fed a good......., although in low abundance of unuseful Delta7 sterols. Obviously, S. sulcatum did not biochemically enhance bacterial or algal food for subsequent use at higher trophic levels, and only transferred fatty acids without further conversion. The results indicate a deficiency in the ciliate of HUFAs and sterols...

  4. ON THE MARINE CILIATE, Pseudocohnilembus hargisi (PROTOZOA, CILIOPHORA, SCUTICOCILIATIDA) WITH COMPARISON OF ITS RELATED SPECIES

    Institute of Scientific and Technical Information of China (English)

    龚骏; 马宏伟; 宋微波

    2002-01-01

    The living morphology, nuclear apparatus, infraciliature and silverline system of the poorly-known ciliate Pseudocohnilembus hargisi Evans & Thompson, 1964, collected from a shrimp culture pond in Qingdao, China, were examined by observation of the live specimen ; and by the pyridinated carbonate method and Chatton-Lwoff technique. The main characteristics: 13 - 14 (usually 13) longitudinal or slightly spirally arranged somatic kineties; single contractile vacuole with usually 2 ( 1 - 2) pores at posterior ends of the fourth and fifth somatic kineties to the fight of the buccal cavity. Several related congeners were compared and morphometrically tabulated.

  5. Scuticociliatid ciliate outbreak in Australian potbellied seahorse, Hippocampus abdominalis (Lesson, 1827): clinical signs, histopathologic findings, and treatment with metronidazole.

    Science.gov (United States)

    Di Cicco, Emiliano; Paradis, Erika; Stephen, Craig; Turba, Maria Elena; Rossi, Giacomo

    2013-06-01

    A severe outbreak of scuticociliatosis occurred in Australian pot-bellied seahorse, Hippocampus abdominalis (Lesson, 1872), kept at the Vancouver Aquarium Marine Science Centre (Vancouver, British Columbia, Canada). Clinical signs included anorexia, lethargy, irregular respiration, and death. Cytology and histopathology revealed a high number of histophagous ciliated protozoa within the tissues. The parasite, identified as Philasterides dicentrarchi, was observed in several internal organs that appeared edematous and hemorrhagic upon postmortem examination. Severe histopathologic lesions were reported in particular in the ovary, the kidney, and the intestine. This infection was successfully treated with metronidazole via bath therapy. No further evidence of this parasite was found in the treated fish.

  6. Migration and differentiation of neural progenitor cells after recurrent laryngeal nerve avulsion in rats.

    Directory of Open Access Journals (Sweden)

    Wan Zhao

    Full Text Available To investigate migration and differentiation of neural progenitor cells (NPCs from the ependymal layer to the nucleus ambiguus (NA after recurrent laryngeal nerve (RLN avulsion. All of the animals received a CM-DiI injection in the left lateral ventricle. Forty-five adult rats were subjected to a left RLN avulsion injury, and nine rats were used as controls. 5-Bromo-2-deoxyuridine (BrdU was injected intraperitoneally. Immunohistochemical analyses were performed in the brain stems at different time points after RLN injury. After RLN avulsion, the CM-DiI+ NPCs from the ependymal layer migrated to the lesioned NA. CM-DiI+/GFAP+ astrocytes, CM-DiI+/DCX+ neuroblasts and CM-DiI+/NeuN+ neurons were observed in the migratory stream. However, the ipsilateral NA included only CM-DiI+ astrocytes, not newborn neurons. After RLN avulsion, the NPCs in the ependymal layer of the 4th ventricle or central canal attempt to restore the damaged NA. We first confirm that the migratory stream includes both neurons and glia differentiated from the NPCs. However, only differentiated astrocytes are successfully incorporated into the NA. The presence of both cell types in the migratory process may play a role in repairing RLN injuries.

  7. Migration and differentiation of neural progenitor cells after recurrent laryngeal nerve avulsion in rats.

    Science.gov (United States)

    Zhao, Wan; Xu, Wen

    2014-01-01

    To investigate migration and differentiation of neural progenitor cells (NPCs) from the ependymal layer to the nucleus ambiguus (NA) after recurrent laryngeal nerve (RLN) avulsion. All of the animals received a CM-DiI injection in the left lateral ventricle. Forty-five adult rats were subjected to a left RLN avulsion injury, and nine rats were used as controls. 5-Bromo-2-deoxyuridine (BrdU) was injected intraperitoneally. Immunohistochemical analyses were performed in the brain stems at different time points after RLN injury. After RLN avulsion, the CM-DiI+ NPCs from the ependymal layer migrated to the lesioned NA. CM-DiI+/GFAP+ astrocytes, CM-DiI+/DCX+ neuroblasts and CM-DiI+/NeuN+ neurons were observed in the migratory stream. However, the ipsilateral NA included only CM-DiI+ astrocytes, not newborn neurons. After RLN avulsion, the NPCs in the ependymal layer of the 4th ventricle or central canal attempt to restore the damaged NA. We first confirm that the migratory stream includes both neurons and glia differentiated from the NPCs. However, only differentiated astrocytes are successfully incorporated into the NA. The presence of both cell types in the migratory process may play a role in repairing RLN injuries.

  8. Effect of the rumen ciliates Entodinium caudatum, Epidinium ecaudatum and Eudiplodinium maggii, and combinations thereof, on ruminal fermentation and total tract digestion in sheep.

    Science.gov (United States)

    Zeitz, Johanna O; Amelchanka, Sergej L; Michałowski, Tadeusz; Wereszka, Krzysztof; Meile, Leo; Hartnack, Sonja; Kreuzer, Michael; Soliva, Carla R

    2012-06-01

    The quantitative importance of individual ciliate species and their interaction in the rumen is still unclear. The present study was performed to test whether there are species differences in the influence on ruminal fermentation in vivo and if combinations of ciliates act additive in that respect. Six adult wethers fed a hay-concentrate diet were defaunated, then refaunated either with Entodinium caudatum (EC), Epidinium ecaudatum (EE) or Eudiplodinium maggii (EM) alone, then progressively with all possible species combinations. Feed, faeces, urine, ruminal fluid and gas were sampled for eight days always after at least 21 days of adaptation. With a linear mixed model, accounting for the 2 x 2 x 2 full factorial study design, mean marginal effect sizes, i.e., the magnitude of change in variables as caused by the presence of each ciliate species or of combinations of them, were estimated. The apparent digestibility of organic matter and neutral detergent fibre remained unaffected. The apparent N digestibility increased by 0.054 with EM (0.716 with defaunation). Ruminal ammonia increased by 1.6, 4.0 and 8.7 mmol/l in the presence of EM, EC and EE, respectively, compared to defaunation (6.9 mmol/l). In the EM + EE combination, ruminal ammonia was lower than would have been expected from an additive effect. With EE, total short-chain fatty acids increased by 23 mmol/l (100 mmol/l with defaunation), but not when EE was combined with EM. The acetate-to-propionate ratio decreased by 0.73 units in the presence of EE (4.0 with defaunation), but only when EE was the sole ciliate species in the rumen. In the presence of any ciliate species, the 16S rDNA copies of total Bacteria and major fibrolytic species decreased to 0.52- and 0.22-fold values, respectively of that found without protozoa. Total Archaea were unaffected; however, Methanobacteriales copies increased 1.44-fold with EC. The CH4-to-CO2 ratio of ruminal gas decreased by 0.036 with EM and 0.051 with EE (0.454 with

  9. 夏季蓝藻水华期间太湖河口区和敞水区纤毛虫群落组成及水平分布%COMMUNITY COMPOSITIONS AND HORIZONTAL DISTRIBUTION OF CILIATES IN LAKE TAIHU DURING THE CYANOBACTERIAL BLOOM IN SUMMER

    Institute of Scientific and Technical Information of China (English)

    李静; 卢文轩; 张雷燕; 陈非洲

    2014-01-01

    In the present study, ciliate samples were collected from 10 sites in the estuary zones and 14 sites in the pe-lagic zones in the northern area of Lake Taihu in July 2009. The ciliate species and their horizontal distribution were analyzed with quantitative protargol stain (QPS) method. We also explored the relationship between the ciliate commu-nity compositions and the environmental variables. We observed 105 species that represented 60 genera, 15 orders and 3 classes. The numbers of the species in different order were counted and compared. Orders Haptorida (21 species) and Oligotrichida (20 species) ranked the first and second, followed by orders Prostomatida (12 species), Peritrichida (11 species), and Hypotrichida (11 species). These five orders were predominant in the samples, while less species belonged to the other ten orders -- Karyorelictida, Pleurostomatida, Colpodida, Nassulida, Cyrophorida, Suctoria, Hy-menostomatida, Synhymeniida, Scuticociliatida, and Heterotrichida. Halteria bifurcate Tamar, H. grandinella Dujardin, Rimostrombidium brachykinetum Krainer, Tintinnopsis cylindrata Kofoid & Campbell and Cyclidium glaucoma Müller were the dominant species in both estuary (3.1%-12.3% in abundance) and pelagic (4.5%-18.1%) zones, followed by Urotricha farcta Claparède & Lachmann, Codonella cratera Leidy, R. humile Penard, Strombidium mirabile Penard, Tintinnidium pusillum Entz, Vorticella aquadulcis complex and V. campanula Ehrenberg. The abundance of ciliate was higher in the estuary zones than that in the pelagic zones, which fell in the range of 1600 to 80900 cells/L (average 31407 cells/L) and 1225 cells/L to 36000 cells/L (average 18618 cells/L), respectively. The biomass of ciliate showed the same pattern which was 1322.6μg/L and 543.6μg/L on average in the estuary and pelagic zones, respectively. Nei-ther the abundance nor the biomass of ciliates showed significant differences (P>0.05). Among the functional feeding groups, bactivorous and

  10. Coding genes and molecular structures of the diffusible signalling proteins (pheromones) of the polar ciliate, Euplotes nobilii.

    Science.gov (United States)

    Vallesi, Adriana; Alimenti, Claudio; Pedrini, Bill; Di Giuseppe, Graziano; Dini, Fernando; Wüthrich, Kurt; Luporini, Pierangelo

    2012-12-01

    In protozoan ciliates, diffusible signalling proteins (pheromones) regulate the vegetative growth and mating interactions. Here, the coding genes and the structures of the encoded pheromones were studied in genetically distinct wild-type strains representing interbreeding Antarctic and Arctic populations of the marine ciliate Euplotes nobilii. Determination of seven allelic pheromone-coding DNA sequences revealed that an unusual extension and high structural conservation of the 5' non-coding region are peculiar traits of this gene family, implying that this region is directly involved in the mechanism of pheromone gene expression, possibly through phenomena of intron splicing and/or frame-shifting. For four pheromones, the three-dimensional structures were determined by nuclear magnetic resonance spectroscopy in solution. These structures show that the pheromones represent a protein family which adapts to its polar environment by combining a structurally stable core of a three-helix bundle with extended polypeptide segments that are devoid of regular secondary structures and concomitantly show enhanced structural flexibility.

  11. OCT-based quantification of flow velocity, shear force, and power generated by a biological ciliated surface (Conference Presentation)

    Science.gov (United States)

    Huang, Brendan K.; Khokha, Mustafa K.; Loewenberg, Michael; Choma, Michael A.

    2016-03-01

    In cilia-driven fluid flow physiology, quantification of flow velocity, shearing force, and power dissipation is important in defining abnormal ciliary function. The capacity to generate flow can be robustly described in terms of shearing force. Dissipated power can be related to net ATP consumption by ciliary molecular motors. To date, however, only flow velocity can be routinely quantified in a non-invasive, non-contact manner. Additionally, traditional power-based metrics rely on metabolic consumption that reflects energy consumption not just from cilia but also from all active cellular processes. Here, we demonstrate the estimation of all three of these quantities (flow velocity, shear force, and power dissipation) using only optical coherence tomography (OCT). Specifically, we develop a framework that can extract force and power information from vectorial flow velocity fields obtained using OCT-based methods. We do so by (a) estimating the viscous stress tensor from flow velocity fields to estimate shearing force and (b) using the viscous stress tensor to estimate the power dissipation function to infer total mechanical power. These estimates have the advantage of (a) requiring only a single modality, (b) being non-invasive in nature, and (c) being reflective of only the net power work generated by a ciliated surface. We demonstrate our all-optical approach to the estimation of these parameters in the Xenopus animal model system under normal and increased viscous loading. Our preliminary data support the hypothesis that the Xenopus ciliated surface can increase force output under loading conditions.

  12. Spinal cord central canal of the German shepherd dog: morphological, histological, and ultrastructural considerations.

    Science.gov (United States)

    Marín-García, P; González-Soriano, J; Martinez-Sainz, P; Contreras-Rodríguez, J; Del Corral-Gros, C; Rodríguez-Veiga, E

    1995-05-01

    This study deals with some macroscopical, microscopical, and ultrastructural aspects of the spinal cord central canal of the German shepherd dog. The caudal end of the spinal cord is constituted by the conus medullaris, which may extend to the first sacral vertebra, the terminal ventricle, and the filum terminale. The latter structure is considered as internum (second to third sacral vertebrae) or externum (fifth caudal vertebra), according to its relation to the dura mater. Occasionally, there is a second anchorage which is close to the level of the sixth caudal vertebra. The central canal is surrounded by a ciliated ependymal epithelium, which differs depending upon the levels. The most caudal part of the filum terminale bears a columnar ciliated ependymal epithelium surrounded by two layers of glia and pia mater, which separate the central canal from the subarachnoid space. Microfil injections show a communication between the cavity and the subarachnoid space, as the plastic is able to pass through the ependymal epithelium. At the level of the terminal ventricle there are real separations of the ependymal epithelium, which seem to connect the lumen of the spinal canal with the subarachnoid space. These structures probably constitute one of the drainage pathways of the cerebrospinal fluid. The diameter of the central canal is related to the age of the animal. However, even in very old animals the spinal cord central canal reaches the tip of the filum terminale and remains patent until death. At the ultrastructural level the ependymal cells present villi, located on cytoplasmic projections, cilia, dense mitochondria, and oval nuclei.

  13. The PDZ Protein Na+/H+ Exchanger Regulatory Factor-1 (NHERF1) Regulates Planar Cell Polarity and Motile Cilia Organization.

    Science.gov (United States)

    Treat, Anny Caceres; Wheeler, David S; Stolz, Donna B; Tsang, Michael; Friedman, Peter A; Romero, Guillermo

    2016-01-01

    Directional flow of the cerebrospinal fluid requires coordinated movement of the motile cilia of the ependymal epithelium that lines the cerebral ventricles. Here we report that mice lacking the Na+/H+ Exchanger Regulatory Factor 1 (NHERF1/Slc9a3r1, also known as EBP50) develop profound communicating hydrocephalus associated with fewer and disorganized ependymal cilia. Knockdown of NHERF1/slc9a3r1 in zebrafish embryos also causes severe hydrocephalus of the hindbrain and impaired ciliogenesis in the otic vesicle. Ultrastructural analysis did not reveal defects in the shape or organization of individual cilia. Similar phenotypes have been described in animals with deficiencies in Wnt signaling and the Planar Cell Polarity (PCP) pathway. We show that NHERF1 binds the PCP core genes Frizzled (Fzd) and Vangl. We further show that NHERF1 assembles a ternary complex with Fzd4 and Vangl2 and promotes translocation of Vangl2 to the plasma membrane, in particular to the apical surface of ependymal cells. Taken together, these results strongly support an important role for NHERF1 in the regulation of PCP signaling and the development of functional motile cilia.

  14. Ciliary-propelling mechanism, effect of temperature and viscosity on swimming speed, and adaptive significance of ‘jumping’ in the ciliate Mesodinium rubrum

    DEFF Research Database (Denmark)

    Riisgård, Hans Ulrik; Larsen, Poul Scheel

    2009-01-01

    Beating cilia are important organelles, not only for water pumping in many active filter-feeding organisms, but also for the swimming activity of ciliates and other aquatic organisms that use cilia for propulsion. The present study concerns the effect of temperature-dependent viscosity of the amb...

  15. Genome-wide identification and evolution of ATP-binding cassette transporters in the ciliate Tetrahymena thermophila: A case of functional divergence in a multigene family

    Directory of Open Access Journals (Sweden)

    Yuan Dongxia

    2010-10-01

    Full Text Available Abstract Background In eukaryotes, ABC transporters that utilize the energy of ATP hydrolysis to expel cellular substrates into the environment are responsible for most of the efflux from cells. Many members of the superfamily of ABC transporters have been linked with resistance to multiple drugs or toxins. Owing to their medical and toxicological importance, members of the ABC superfamily have been studied in several model organisms and warrant examination in newly sequenced genomes. Results A total of 165 ABC transporter genes, constituting a highly expanded superfamily relative to its size in other eukaryotes, were identified in the macronuclear genome of the ciliate Tetrahymena thermophila. Based on ortholog comparisons, phylogenetic topologies and intron characterizations, each highly expanded ABC transporter family of T. thermophila was classified into several distinct groups, and hypotheses about their evolutionary relationships are presented. A comprehensive microarray analysis revealed divergent expression patterns among the members of the ABC transporter superfamily during different states of physiology and development. Many of the relatively recently formed duplicate pairs within individual ABC transporter families exhibit significantly different expression patterns. Further analysis showed that multiple mechanisms have led to functional divergence that is responsible for the preservation of duplicated genes. Conclusion Gene duplications have resulted in an extensive expansion of the superfamily of ABC transporters in the Tetrahymena genome, making it the largest example of its kind reported in any organism to date. Multiple independent duplications and subsequent divergence contributed to the formation of different families of ABC transporter genes. Many of the members within a gene family exhibit different expression patterns. The combination of gene duplication followed by both sequence divergence and acquisition of new patterns of

  16. The giant ciliate Zoothamnium niveum and its thiotrophic epibiont Candidatus Thiobios zoothamnicoli: a model system to study interspecies cooperation

    Directory of Open Access Journals (Sweden)

    Monika eBright

    2014-04-01

    Full Text Available Symbioses between chemoautotrophic sulfur-oxidizing (thiotrophic bacteria and protists or animals are among the most diverse and prevalent in the ocean. They are extremely difficult to maintain in aquaria and no thiotrophic symbiosis involving an animal host has ever been successfully cultivated. In contrast, we have cultivated the giant ciliate Zoothamnium niveum and its obligate ectosymbiont Cand. Thiobios zoothamnicoli in small flow-through aquaria. This review provides an overview of the host and the symbiont and their phylogenetic relationships. We summarize our knowledge on the ecology, geographic distribution and life cycle of the host, on the vertical transmission of the symbiont, and on the cultivation of this symbiosis. We then discuss the benefits and costs involved in this cooperation compared with other thiotrophic symbioses and outline our view on the evolution and persistence of this byproduct mutualism.

  17. Complementary Notes on a‘Well-known' Marine Heterotrichous Ciliate, Folliculinopsis producta (Wright, 1859) Fraure-Fremiet,1936 (Protozoa, Ciliophora)

    Institute of Scientific and Technical Information of China (English)

    JI Daode; LIN Xiaofeng; SONG Weibo

    2004-01-01

    The living morphology and infraciliature of a heterotrichous ciliate, Folliculinopsis producta (Wright, 1859)Fraure-Fremiet, 1936, which was collected from the north coast of China, were investigated by in vivo observation and protargol impregnation techniques. As a new contribution, a redescription is presented: large Folliculinopsis of green to dark green in color, 800-1500μm in size; two peristomial lobes of approximately equal size, 300-400μm in length; adoral zone of membranelles containing about 1000 membranelles, lying along lobe margins and exhibiting two circles within buccal cavity;50-70 somatic kineties in mid-body; macronucleus miniliform, consisting of about 20 beads; lorica smooth, vase-shaped,(300 500)μm ×(90-130)μm in size, with 5-12 spiral ridges on neck tube; marine habitat.

  18. Insights into the phylogeny of sporadotrichid ciliates (Protozoa, Ciliophora: Hypotricha) based on genealogical analyses of multiple molecular markers

    Institute of Scientific and Technical Information of China (English)

    HU Xiaoyan; HU Xiaozhong; Khaled A. S. AL-RASHEID; Saieh A. AL-FARRAJ; SONG Weibo

    2011-01-01

    The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent classification is still lacking and several important questions about the phylogenetic relationships within this group remain unsolved. To improve our understanding of these relationships, we constructed phylogenetic trees using the nucleotide sequences of the small-subunit rRNA (SSrRNA) gene and amino acid sequences of actin I and -αtubulin. Analyses of SSrRNA gene sequences indicated that: 1) the Sporadotrichida sensu Lynn (2008) and the Oxytrichidae are polyphyletic; 2) the Uroleptus species, which are classified to urostylids, formed a sister group with the oxytrichids; 3) Halteria grandinella, which is grouped morphologically with oligotrich species, clustered within the oxytrichids. These results are congruent with previous studies based on SSrRNA gene sequences. However, the amino acid sequences of actin I and α-tubulin yielded different topologies. The main results are: 1) in all phylogenetic trees, the genus Oxylricha was paraphyletic; 2) Uroleptus was sister to a subset of Urostyla and Holosticha, albeit with low supporting values; 3) Halteria grandinella was separated distantly from the Oxytrichidae in trees inferred from actin I amino acid sequences but clustered with oligotrichids in the α-tubulin analysis. The inconsistency among the trees inferred from these different molecular markers may be caused by rapidly accumulated genetic characterizations of ciliates. Further studies with additional molecular markers and sampling of more taxa are expected to better address the relationships among sporadotrichids.

  19. Insights into the phylogeny of sporadotrichid ciliates (Protozoa, Ciliophora: Hypotricha) based on genealogical analyses of multiple molecular markers

    Science.gov (United States)

    Hu, Xiaoyan; Hu, Xiaozhong; Al-Rasheid, Khaled A. S.; Al-Farraj, Saleh A.; Song, Weibo

    2011-01-01

    The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent classification is still lacking and several important questions about the phylogenetic relationships within this group remain unsolved. To improve our understanding of these relationships, we constructed phylogenetic trees using the nucleotide sequences of the small-subunit rRNA (SSrRNA) gene and amino acid sequences of actin I and α-tubulin. Analyses of SSrRNA gene sequences indicated that: 1) the Sporadotrichida sensu Lynn (2008) and the Oxytrichidae are polyphyletic; 2) the Uroleptus species, which are classified to urostylids, formed a sister group with the oxytrichids; 3) Halteria grandinella, which is grouped morphologically with oligotrich species, clustered within the oxytrichids. These results are congruent with previous studies based on SSrRNA gene sequences. However, the amino acid sequences of actin I and α-tubulin yielded different topologies. The main results are: 1) in all phylogenetic trees, the genus Oxytricha was paraphyletic; 2) Uroleptus was sister to a subset of Urostyla and Holosticha, albeit with low supporting values; 3) Halteria grandinella was separated distantly from the Oxytrichidae in trees inferred from actin I amino acid sequences but clustered with oligotrichids in the α-tubulin analysis. The inconsistency among the trees inferred from these different molecular markers may be caused by rapidly accumulated genetic characterizations of ciliates. Further studies with additional molecular markers and sampling of more taxa are expected to better address the relationships among sporadotrichids.

  20. Seasonal and spatial dynamics of a ciliate assemblage in a warm-monomictic Lake Alchichica (Puebla, Mexico Dinámica temporal y espacial de la comunidad de ciliados en un lago monomíctico-cálido Alchichica (Puebla, México

    Directory of Open Access Journals (Sweden)

    Miroslav Macek

    2008-08-01

    Full Text Available The distribution of the ciliate assemblage was surveyed along a depth gradient in the maar crater, athalassohaline, warm monomictic Lake Alchichica (Puebla, Mexico from June 2003 to October 2006 (monthly. DAPI staining was employed to count ciliates while the Quantitative Protargol Staining was used for their identification. Peritrichs often numerically dominated the ciliate assemblage; a maximum of 54 cells ml-1 (Rhabdostyla sp. was observed in the surface layer at the end of the mixing period, during the development of diatoms (Cyclotella alchichicana, cyanobacterial (Nodularia sp. bloom and its decay. Minute spirotrichs (particularly Halteria grandinella and a haptorid, Belonophrya pelagica occasionally dominated the epilimnion while mixotrophic Euplotes cf. daidaleos and Pelagothrix sp. were important round the oxycline along with haptorids, particularly Phialina sp. Scuticociliates Cyclidium glaucoma, Uronema nigricans, and anaerobic ciliates Isocyclidium globosum and Caenomorpha sp. dominated within the hypolimnetic assemblages.De junio de 2003 a diciembre de 2006 se estudió mensualmente la distribución de la comunidad de ciliados en el gradiente de profundidades del Lago Alchichica (Puebla, México, un lago cráter, tipo maar, atalasohalino de comportamiento monomíctico-cálido. La tinción de DAPI fue empleada para el recuento de los ciliados y la tinción de protargol cuantitativa para su identificación. Frecuentemente los ciliados perítricos dominaron numéricamente la comunidad. Al final del periodo de estratificación y durante el desarrollo de las diatomeas (Cyclotella alchichicana y el florecimiento y posterior decaimiento de las cianobacterias filamentosas (Nodularia sp., se observó un máximo de 54 cél. ml-¹ de Rhabdostyla sp. en la superficie del lago. Los espirotricos pequeños (particularmente Halteria grandinella y los haptóridos como Belonophrya pelagica, dominaron ocasionalmente en el epilimnion, mientras que los

  1. Ontogeny of electrically excitable cells in cultured olfactory epithelium.

    OpenAIRE

    Schubert, D; Stallcup, W.; LaCorbiere, M; Kidokoro, Y; Orgel, L

    1985-01-01

    A primary system has been developed in which it is possible to study the production of electrically excitable neuron-like cells from a precursor population of olfactory epithelial cells. Rat nasal epithelium was dissociated and placed in culture. The initial surviving cells are flat and ciliated and contain glial fibrillary acidic protein (GFAP). After 3-5 days electrically excitable cells appear that contain neuron-specific enolase but not GFAP. These round cells originate by means of the di...

  2. Cell fate control in the developing central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Guérout, Nicolas; Li, Xiaofei; Barnabé-Heider, Fanie, E-mail: Fanie.Barnabe-Heider@ki.se

    2014-02-01

    The principal neural cell types forming the mature central nervous system (CNS) are now understood to be diverse. This cellular subtype diversity originates to a large extent from the specification of the earlier proliferating progenitor populations during development. Here, we review the processes governing the differentiation of a common neuroepithelial cell progenitor pool into mature neurons, astrocytes, oligodendrocytes, ependymal cells and adult stem cells. We focus on studies performed in mice and involving two distinct CNS structures: the spinal cord and the cerebral cortex. Understanding the origin, specification and developmental regulators of neural cells will ultimately impact comprehension and treatments of neurological disorders and diseases. - Highlights: • Similar mechanisms regulate cell fate in different CNS cell types and structures. • Cell fate regulators operate in a spatial–temporal manner. • Different neural cell types rely on the generation of a diversity of progenitor cells. • Cell fate decision is dictated by the integration of intrinsic and extrinsic signals.

  3. Impacts of an uncontrolled phosphogypsum dumpsite on summer distribution of phytoplankton, copepods and ciliates in relation to abiotic variables along the near-shore of the southwestern Mediterranean coast.

    Science.gov (United States)

    Rekik, Amira; Drira, Zaher; Guermazi, Wassim; Elloumi, Jannet; Maalej, Sami; Aleya, Lotfi; Ayadi, Habib

    2012-02-01

    In connection with the Taparura Project, studies of spatial distribution of the crustacean zooplankton community, nutrients, phytoplankton and ciliates were conducted in July 2007 at 45 stations spread over fifteen transects along the coast north of Sfax. The results showed that the N/P ratio was lower than the Redfield ratio, suggesting potential N limitation. Phytoplankton was characterised by the proliferation of several diatoms, while ciliates were largely dominated by spirotrichs. Copepods were the most abundant zooplankton present during the entire study period, comprising 61% of the total zooplankton community. Twelve copepod families were identified at every station, with a high percentage of Oithonidae (77% of copepods) dominated by Oithona nana. The abundance of this species was correlated with that of diatoms, Cocoolithophorideae and ciliated Colpodea, suggesting that O. nana may feed on a wide range of prey. Despite human pressure and industrial activities, the coastal waters north of Sfax showed a wide diversity of phytoplankton, ciliates and zooplankton.

  4. [Morphological variations of the nuclear apparatus of astome ciliates Almophrya bivacuolata and A. maediovacuolata (protozoa: ciliophora) endocommensal of terricolous oligochaetes in Cameroon].

    Science.gov (United States)

    Nana, P A; Ngassam, P; Fokam, Z; Bricheux, G; Bouchard, P; Coffe, G; Sime, Gando T; Zébazé, Togouet S H

    2010-12-01

    The silver impregnation supplemented by DAPI and Feulgen nuclear coloration enabled us to study the morphological variations of the nuclear apparatus of two species of endocommensal Astome ciliates, Almophrya bivacuoloata (de Puytorac & Dragesco, 1968) and A. mediovocuolata (Ngassam, 1983). We highlighted important digitations and the presence of dark bands in the structure of the "H" macronucleus of the small cellular types as well as the presence of intermediate forms between "H" and "X" in these two species.

  5. Impacts of restoration of an uncontrolled phosphogypsum dumpsite on the seasonal distribution of abiotic variables, phytoplankton, copepods, and ciliates in a man-made solar saltern.

    Science.gov (United States)

    Kobbi-Rebai, Rayda; Annabi-Trabelsi, Neila; Khemakhem, Hajer; Ayadi, Habib; Aleya, Lotfi

    2013-03-01

    The restoration of an uncontrolled phosphogypsum landfill was investigated for its effects on the seasonal distribution of phytoplankton, ciliates, and copepods. Sampling was carried out monthly from September 2007 to August 2008 at four ponds of increasing salinity (A1, 41 psu; A5, 46 psu; A16, 67 psu; and C31, 77 psu) in the Sfax solar saltern (southeastern Tunisia). Physicochemical and biological analyses were carried out using standard methods. Results showed drastic reduction of phosphate input and greater diversity of phytoplankton, ciliates, and copepods than before restoration. Pennate diatoms and new ciliates, considered bio-indicators of less-stressed marine ecosystems, proliferated in the A1 pond for the first time after restoration. Copepods appeared to feed on a wide range of prey. Economically, removal of the 1.7 million m(3) of phosphate improved the quality of the site's salt production, enabling the salt company to receive the quality ISO 9001 accreditation.

  6. Infraciliature and morphogenesis in three rumen Diplodinium ciliates, Diplodinium polygonale, Diplodinium leche, and Diplodinium nanum, observed by light microscopy.

    Science.gov (United States)

    Ito, Akira; Imai, Soichi

    2005-01-01

    Infraciliature and morphogenesis of three rumen ophryoscolecid ciliates, Diplodinium polygonale Dogiel, 1925, Diplodinium leche Imai et al., 1992, and Diplodinium nanum Imai, 1988, are described from pyridinated silver carbonate-impregnated specimens. These three species have two polybrachykineties in the buccal area and a polybrachykinety in the dorsal ciliary zone. The vestibular polybrachykinety (VP) of D. polygonale and D. leche arises from the dorsal extremity of the adoral polybrachykinety (AP) as in Entodinium species, extending toward the left in D. polygonale and toward the left posterior in D. leche. The VP of D. nanum arises from the inner side of the AP, separate from its dorsal extremity, as in other Diplodinium species and extends toward the left posterior. These series of the polybrachykinety arrangements in D. polygonale, D. leche, and D. nanum can be regarded as transitional forms in the evolution of an Entodinium-like ancestor to Diplodinium. Morphogenesis of these three Diplodinium species is not different from that of other Diplodinium species.

  7. Estimation of divergence times in litostomatean ciliates (Ciliophora: Intramacronucleata), using Bayesian relaxed clock and 18S rRNA gene.

    Science.gov (United States)

    Vďačný, Peter

    2015-08-01

    The class Litostomatea comprises a diverse assemblage of free-living and endosymbiotic ciliates. To understand diversification dynamic of litostomateans, divergence times of their main groups were estimated with the Bayesian molecular dating, a technique allowing relaxation of molecular clock and incorporation of flexible calibration points. The class Litostomatea very likely emerged during the Cryogenian around 680 Mya. The origin of the subclass Rhynchostomatia is dated to about 415 Mya, while that of the subclass Haptoria to about 654 Mya. The order Pleurostomatida, emerging about 556 Mya, was recognized as the oldest group within the subclass Haptoria. The order Spathidiida appeared in the Paleozoic about 442 Mya. The three remaining haptorian orders evolved in the Paleozoic/Mesozoic periods: Didiniida about 419 Mya, Lacrymariida about 269 Mya, and Haptorida about 194 Mya. The subclass Trichostomatia originated from a spathidiid ancestor in the Mesozoic about 260 Mya. A further goal of this study was to investigate the impact of various settings on posterior divergence time estimates. The root placement and tree topology as well as the priors of the rate-drift model, birth-death process and nucleotide substitution rate, had no significant effect on calculation of posterior divergence time estimates. However, removal of calibration points could significantly change time estimates at some nodes.

  8. Morphology, ontogeny and molecular phylogeny of a novel saline soil ciliate, Urosomoida paragiliformis n. sp. (Ciliophora, Hypotrichia).

    Science.gov (United States)

    Wang, Jingyi; Lyu, Zhao; Warren, Alan; Wang, Feng; Shao, Chen

    2016-10-01

    The living morphology, infraciliature and morphogenesis of a new ciliate, Urosomoida paragiliformis n. sp., collected from saline soil in Weinan, China, were studied in vivo and after protargol staining. Urosomoida paragiliformis n. sp. is characterized as follows: body elongate-elliptical with no tail, flexible and slightly contractile; cortical granules dark-brown, 0.5μm across, arranged in short irregular rows; about 33 adoral membranelles; 14 frontoventral-transverse cirri; right and left marginal rows not confluent posteriorly; two macronuclear nodules. Morphogenesis of U. paragiliformis n. sp. corresponds well with that of other Urosomoida-species except that in reorganisers the oral primordium develops membranelles that replace those at the proximal end of the old adoral zone, whereas in dividers the entire parental adoral zone of membranelles is inherited by the proter. Phylogenetic analyses based on SSU rDNA sequence data suggest a close relationship between U. paragiliformis n. sp. and Paraurosomoida indiensis. A new combination is made: Oxytrichella subtropica (Fan et al., 2015) comb. nov. (basionym Urosomoida subtropica).

  9. Tissue mortality by Caribbean ciliate infection and white band disease in three reef-building coral species.

    Science.gov (United States)

    Verde, Alejandra; Bastidas, Carolina; Croquer, Aldo

    2016-01-01

    Caribbean ciliate infection (CCI) and white band disease (WBD) are diseases that affect a multitude of coral hosts and are associated with rapid rates of tissue losses, thus contributing to declining coral cover in Caribbean reefs. In this study we compared tissue mortality rates associated to CCI in three species of corals with different growth forms: Orbicella faveolata (massive-boulder), O. annularis (massive-columnar) and Acropora cervicornis (branching). We also compared mortality rates in colonies of A. cervicornis bearing WBD and CCI. The study was conducted at two locations in Los Roques Archipelago National Park between April 2012 and March 2013. In A. cervicornis, the rate of tissue loss was similar between WBD (0.8 ± 1 mm/day, mean ± SD) and CCI (0.7 ± 0.9 mm/day). However, mortality rate by CCI in A. cervicornis was faster than in the massive species O. faveolata (0.5 ± 0.6 mm/day) and O. annularis (0.3 ± 0.3 mm/day). Tissue regeneration was at least fifteen times slower than the mortality rates for both diseases regardless of coral species. This is the first study providing coral tissue mortality and regeneration rates associated to CCI in colonies with massive morphologies, and it highlights the risks of further cover losses of the three most important reef-building species in the Caribbean.

  10. Tissue mortality by Caribbean ciliate infection and white band disease in three reef-building coral species

    Directory of Open Access Journals (Sweden)

    Alejandra Verde

    2016-07-01

    Full Text Available Caribbean ciliate infection (CCI and white band disease (WBD are diseases that affect a multitude of coral hosts and are associated with rapid rates of tissue losses, thus contributing to declining coral cover in Caribbean reefs. In this study we compared tissue mortality rates associated to CCI in three species of corals with different growth forms: Orbicella faveolata (massive-boulder, O. annularis (massive-columnar and Acropora cervicornis (branching. We also compared mortality rates in colonies of A. cervicornis bearing WBD and CCI. The study was conducted at two locations in Los Roques Archipelago National Park between April 2012 and March 2013. In A. cervicornis, the rate of tissue loss was similar between WBD (0.8 ± 1 mm/day, mean ± SD and CCI (0.7 ± 0.9 mm/day. However, mortality rate by CCI in A. cervicornis was faster than in the massive species O. faveolata (0.5 ± 0.6 mm/day and O. annularis (0.3 ± 0.3 mm/day. Tissue regeneration was at least fifteen times slower than the mortality rates for both diseases regardless of coral species. This is the first study providing coral tissue mortality and regeneration rates associated to CCI in colonies with massive morphologies, and it highlights the risks of further cover losses of the three most important reef-building species in the Caribbean.

  11. Morphologic and Genetic Variability in the Marine Planktonic Ciliate Laboea strobila Lohmann, 1908 (Ciliophora, Oligotrichia), with Notes on its Ontogenesis

    Science.gov (United States)

    AGATHA, SABINE; STRÜDER-KYPKE, MICHAELA C.; BERAN, ALFRED

    2010-01-01

    Laboea strobila Lohmann, 1908 is a conspicuous oligotrich ciliate in the marine plankton. In order to compare different populations, the morphology of specimens from the Mediterranean Sea, North Sea, and Irish Sea was investigated using live observation, protargol impregnation, and scanning electron microscopy. Furthermore, the PCR-amplified products of the SSrRNA gene from a monoclonal culture of L. strobila from the Mediterranean Sea were sequenced and aligned with sequences of other oligotrichs, including a population of L. strobila from the Atlantic coast of the USA. Finally, the data from the ecological literature were summarized and the cultivation methods were described. The SSrRNA gene sequences of the two distantly located L. strobila populations from the North Atlantic are identical. Likewise, the morphometrics of most populations so far investigated after protargol impregnation (i.e. from the North Atlantic) do not show obvious differences. In all computed phylogenetic trees, L. strobila groups with Strombidium species, forming a monophyletic taxon corresponding to the subclass Oligotrichia. These results are corroborated by the ontogenetic comparison. Since no type species was fixed for Laboea Lohmann, 1908, L. strobila was designated in the present paper. PMID:15218695

  12. Several RNase T2 enzymes function in induced tRNA and rRNA turnover in the ciliate Tetrahymena

    DEFF Research Database (Denmark)

    Andersen, Kasper Langebjerg; Collins, Kathleen

    2012-01-01

    RNase T2 enzymes are produced by a wide range of organisms and have been implicated to function in diverse cellular processes, including stress-induced anticodon loop cleavage of mature tRNAs to generate tRNA halves. Here we describe a family of eight RNase T2 genes (RNT2A-RNT2H) in the ciliate...... Tetrahymena thermophila. We constructed strains lacking individual or combinations of these RNT2 genes that were viable but had distinct cellular and molecular phenotypes. In strains lacking only one Rnt2 protein or lacking a subfamily of three catalytically inactive Rnt2 proteins, starvation-induced tRNA...... fragments continued to accumulate, with only a minor change in fragment profile in one strain. We therefore generated strains lacking pairwise combinations of the top three candidates for Rnt2 tRNases. Each of these strains showed a distinct starvation-specific profile of tRNA and rRNA fragment accumulation...

  13. Ciliated cultured dermal fibroblasts in a patient with hyperornithinemia, hyperammonemia and homocitrullinuria (HHH) syndrome.

    Science.gov (United States)

    Haust, M D

    1995-10-01

    Hyperornithinemia, hyperammonemia and homocitrullinuria (HHH)-syndrome is a rare autosomal recessive disorder of the urea cycle, probably caused by a defect in ornithine transport across the hepatic inner mitochondrial membrane. Single rudimentary cilia were present in approximately ten percent of post-divisional or dividing fibroblasts cultured from the skin of a patient with the HHH-syndrome, whereas no such organelles were observed in dermal fibroblasts cultured from normal controls. Since single rudimentary ("primary," "oligo," "solitary") cilia have been observed in a variety of cells in animals and men but the stimuli for their formation and their significance remain controversial, a brief report on their presence in the as yet unreported condition (HHH-syndrome) was considered of interest; hopefully, it might contribute to the ultimate unravelling of some of the unresolved problems. It is of note that unlike the author's previous findings of these unusual organelles in cells affected by a pathological process (atherosclerosis), the rudimentary cilia were observed in the present instance in dividing or postdivisional cells. The implications of these (and other) observations must await further work.

  14. Monoclonal Antibodies as Probes for Unique Antigens in Secretory Cells of Mixed Exocrine Organs

    Science.gov (United States)

    Basbaum, C. B.; Mann, J. K.; Chow, A. W.; Finkbeiner, W. E.

    1984-07-01

    In the past, it has been difficult to identify the secretory product and control mechanisms associated with individual cell types making up mixed exocrine organs. This report establishes the feasibility of using immunological methods to characterize both the biochemical constituents and regulatory mechanisms associated with secretory cells in the trachea. Monoclonal antibodies directed against components of tracheal mucus were produced by immunizing mice with dialyzed, desiccated secretions harvested from tracheal organ culture. An immunofluorescence assay revealed that of the total 337 hybridomas screened, 100 produced antibodies recognizing goblet cell granules; 64, gland cell granules; and 3, antigen confined to the ciliated apical surface of the epithelium. The tracheal goblet cell antibody described in this report was strongly cross-reactive with intestinal goblet cells, as well as with a subpopulation of submandibular gland cells, but not with cells of Brunner's glands or the ciliated cell apical membrane. The serous cell antibody was not cross-reactive with goblet, Brunner's gland, or submandibular cells, or the ciliated cell apical membrane. The antibody directed against the apical membrane of ciliated cells did not cross-react with gland or goblet cells or the apical membrane of epithelial cells in the duodenum. Monoclonal antibodies, therefore, represent probes by which products unique to specific cells or parts of cells in the trachea can be distinguished. The antibodies, when used in enzyme immunoassays, can be used to quantitatively monitor secretion by individual cell types under a variety of physiological and pathological conditions. They also provide the means for purification and characterization of cell-specific products by immunoaffinity chromatography.

  15. Functional intron+ and intron- rDNA in the same macronucleus of the ciliate Tetrahymena pigmentosa

    DEFF Research Database (Denmark)

    Nielsen, Henrik; Engberg, J

    1985-01-01

    alleles was followed in the total culture and in single cells during their vegetative segregation and it was observed that replication was non-preferential with respect to the two alleles. The diallelic clones were also used to demonstrate that intron-containing rDNA was transcribed and the transcript......Diallelic clones of Tetrahymena pigmentosa containing equal amounts of intron+ and intron- rDNA in the macronucleus were constructed. The macronucleus of the resulting strains divides amitotically during vegetative growth and the diallelic genotype is therefore unstable. The coexistence of the two...

  16. Ciliated protists from the nepheloid layer and water column of sites affected by the Deepwater Horizon oil spill in the Northeastern Gulf of Mexico

    Science.gov (United States)

    Moss, Joseph A.; McCurry, Chelsea; Tominack, Sarah; Romero, Isabel C.; Hollander, David; Jeffrey, Wade H.; Snyder, Richard A.

    2015-12-01

    Benthic marine protists have been well documented from shallow marine benthic habitats but remain understudied in deeper habitats on continental shelves and slopes, particularly in the Northeastern Gulf of Mexico (NEGOM). This region was affected by a deep water oil well failure (BP-Deepwater Horizon, 2010). The combination of a lack of information on deep sea microbenthic communities and the potential for benthic microbial petroleum mineralization prompted this investigation. Water column and nepheloid layer samples were obtained via Niskin bottles and a multicorer respectively at stations across the NEGOM to: (1) determine whether nepheloid and water column communities are distinct and (2) assess benthic species richness relative to sediment PAH contamination. Phylum specific 18S rRNA gene amplification was used to construct clone libraries of ciliate assemblages. BLAST searches in the NCBI database indicated that a majority (~75%) of the clone sequences corresponded (94-100% similarity) with listed, yet unclassified sequences. Several putative species were common at most site locations and depths. Many known benthic ciliates, such as Uronychia transfuga, Uronychia setigera, and Spirotrachelostyla tani, were common in the nepheloid layer samples and not recovered in water column samples. Ciliated protist species richness increased with PAH levels found in surface sediments, suggesting a positive microbial response to petroleum enrichment of the benthos. The presence of previously unknown microbenthic communites in the nephaloid layer over oceanic clay-silt muds alters our view of microbial processes in the deep sea and merits investigation of the microbial processes and rates of microbial mineralization and biomass production important to global biogeochemistry.

  17. Ciliates (Protozoa from dried sediments of a temporary pond from Argentina Ciliados (Protozoa de sedimentos secos de una charca temporaria de la Argentina

    Directory of Open Access Journals (Sweden)

    Gabriela Cristina Küppers

    2009-12-01

    Full Text Available Temporary ponds represent special environments that are inhabited by organisms adapted to changing environmental conditions. Ciliates are able to survive complete loss of water in these transient habitats through cyst formation. However, ciliates from the Neotropical region in general have been poorly studied with modern techniques. The main goal of this study is to describe the ciliates in dried sediments of a temporary pond from Buenos Aires Province, Argentina, through sampling efforts that were performed 2003-2005. Soil samples were obtained during drought phases and re wetted in laboratory to establish raw and enriched cultures. Ciliates were then studied both in vivo and after impregnation with protargol. In this study, we present 4 new records for Argentina (Gonostomum affine (Stein, 1859 Sterki, 1878, Stylonychia bifaria (Stokes, 1887 Berger, 1999, Pleurotricha lanceolata (Ehrenberg, 1835 Stein, 1859, Meseres corlissi Petz and Foissner, 1992, 1 for South America (Blepharisma americanum (Suzuki, 1954 Hirshfield, Isquith and Bhandary, 1965, and 2 for the Neotropical Realm (Gonostomum strenuum (Engelmann, 1862 Sterki, 1878, Stylonychia lemnae Ammermann and Schlegel, 1983.Los cuerpos de agua temporarios son ambientes particulares que se encuentran habitados por organismos adaptados a condiciones fluctuantes. Los ciliados son capaces de sobrevivir a la pérdida completa de agua del ambiente gracias a la formación de estructuras de resistencia. Por otra parte, los ciliados de la región Neotropical han sido poco investigados con técnicas modernas. El objetivo de este estudio es referir los ciliados que se desarrollaron a partir de los sedimentos secos de una charca temporaria de la provincia de Buenos Aires, Argentina, en la que se realizaron muestreos durante el período 2003-2005. Las muestras de suelo fueron obtenidas durante las fases de sequía y luego resuspendidas en el laboratorio para realizar cultivos naturales y enriquecidos. Los

  18. Identification of cAMP-dependent phosphorylated proteins involved in the formation of environment-resistant resting cysts by the terrestrial ciliate Colpoda cucullus

    Directory of Open Access Journals (Sweden)

    Y Sogame

    2014-07-01

    Full Text Available In the terrestrial ciliate Colpoda cucullus, an elevation of the intracellular cAMP concentration was reported to be involved in environment-resistant resting cyst formation. In the present study, cAMP-dependently phosphorylated proteins of encystment-induced C. cucullus were isolated with Phos-tag agarose phosphate-affinity beads and subsequent SDS-PAGE. In a liquid chromatography/tandem mass spectrometry analysis of these phosphoproteins, 27-, 37- and 43-kDa proteins (p27, p37 and p43 were identified as Rieske iron-sulfur protein, histone H4 (hyperacetylated form, and actin, respectively.

  19. Phylogenetic positions of two marine ciliates, Metanophrys similis and Pseudocohnilembus hargisi (Protozoa, Ciliophora, Scuticociliatia), inferred from complete small subunit rRNA gene sequences

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The small subunit rRNA (SSrRNA) gene was sequenced for two marine scuticociliates Metanophrys similis and Pseudocohnilembus hargisi. The results show that this gene comprises 1763 and 1753 nucleotides in the two marine ciliates respectively.Metanophrys similis is phylogenetically closely related to the clade containing Mesanophrys carcini and Anophyroides haemophila, which branches basally to other species within the order Philasterida. Pseudocohnilembus hargisi groups with its congener, P. marinus, with strong bootstrap support. Paranophrys magna groups with the clade including Cohnilembus and Uronema, representing a sister clade to that containing the two Pseudocohnilembus species.

  20. Ciliate protozoa of the forestomach of llamas (Lama glama) from locations at different altitude in Argentina.

    Science.gov (United States)

    Cucchi, María Cerón; Marcoppido, Gisela; Dekker, Anna; Fondevila, Manuel; Fuente, Gabriel De La; Morici, Gabriel; Cravero, Silvio

    2016-01-20

    This study describes the diversity and concentration of the protozoal population from the forestomach of llamas in Argentina at three altitudinal locations. Protozoal diversity was studied in samples from eight llamas from Hurlingham (Buenos Aires, 43 m altitude), four from Tilcara (Jujuy, 2465 m altitude) and six llamas from Cieneguillas (Jujuy, 3800 m altitude). The total concentrations of protozoa in the forestomach contents were 7.9, 9.1 and 4.1 cells x 104 ml-1 in Hurlingham, Tilcara and Cieneguillas, respectively (P>0.05). Entodinium spp. represented 97.9, 92.3 and 71.4% of the protozoal community in Hurlingham, Tilcara and Cieneguillas, respectively, and the remaining protozoa belonged to the Eudiplodinium genus. Entodinium spp. were identified as E. caudatum (mostly morphotype dubardi), E. longinucleatum, E. parvum, E. bovis, E. exiguum, E. dubardi, and a minor presence of E. bimastus (in three animals) and E. ovibos (in one animal). In regards to the rest of protozoal species, Eudiplodinium maggii is the first reported host record for the genus in llamas. This species was present in the forestomach of 14 out of 18 llamas tested, and in one case it was the unique protozoal species. The vestibuliferids, Dasytricha and Isotricha were absent from the forestomach of llamas. Similarly, other species such as those from the Caloscolex genus, Diplodinium cameli and Entodinium ovumrajae, commonly found in Old World Camelids, were also absent from llamas.

  1. Proliferation and differentiation of reactive nestin~+/GFAP~+ cells in an adult rat model of compression-induced spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Pinglin Yang; Xijing He; Haopeng Li; Binshang Lan; Guoyu Wang; Yiheng Liu

    2009-01-01

    BACKGROUND:Studies have demonstrated that astrocytes may possess similar properties to neural stem cells/neural precursor cells and have the potential to differentiate into neurons.OBJECTIVE:To observe neuroepithelial stem cell protein (nestin) and glial fibrillary acidic protein (GFAP) expression following spinal cord injury,and to explore whether nestin~+/GFAP~+ cells,which are detected at peak levels in gray and white matter around the ependymal region of the central canal in injured spinal cord,possess similar properties of neural stem cells.DESIGN,TIME AND SETTING:A randomized,controlled experiment.The study was performed at the Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University),Ministry of Education between January 2004 and December 2006.MATERIALS:Rabbit anti-rat nestin,β-tubulin Ⅲ,mouse anti-rat GFAP,galactocerebroside (GaLC) antibodies were utilized,as well as flow cytometry.METHODS:A total of 60 male,Sprague Dawiey rats,aged 8 weeks,were randomly assigned to control (n=12) and model (n=48) groups.The spinal cord injury model was established in the model group by aneurysm clip compression,while the control animals were not treated.The gray and white matter around the ependymal region of the central canal exhibited peak expression of nestin~+/GFAP~+ cells.These cells were harvested and prepared into single cell suspension,followed by primary and passage cultures.The cells were incubated with serum-containing neural stem cell complete medium.MAIN OUTCOME MEASURES:Nestin and GFAP expression in injured spinal cord was determined using immunohistochemistry and double-labeled immunofluorescence at 1,3,5,7,14,28,and 56 days post-injury.In addition,cell proliferation and differentiation were detected using immunofluorescence cytochemistry and flow cytometry.RESULTS:Compared with the control group,the model group exhibited significantly increased nestin and GFAP expression (P<0.05),which reached peak levels between 3 and 7

  2. Morphology, morphogenesis and gene sequence of a freshwater ciliate, Pseudourostyla cristata (Ciliophora, Urostyloidea) from the ancient Lake Biwa, Japan.

    Science.gov (United States)

    Chen, Xumiao; Li, Zicong; Hu, Xiaozhong; Kusuoka, Yasushi

    2010-01-01

    The urostyloid freshwater ciliate Pseudourostyla cristata was recorded for the first time from Lake Biwa, a 4-million-year-old lake located in Shiga Prefecture, Japan. Its morphology and morphogenesis were investigated using live observation and protargol impregnation, and the SSU ribosomal RNA gene was sequenced. Based on the current observations and previous descriptions, this species is readily recognized mainly by the following characters: body slender or broadly oval to elliptical, and dark grey in color; size in vivo about 170-400 x 40-150 microm; pellicle flexible and contractile, with extrusomes forming a hyaline seam underneath; ciliature comprising about 60-130 adoral membranelles, usually 1 buccal cirrus, 20-24 frontal, 2 frontoterminal, 17-26 pairs of midventral, and 5-16 transverse cirri, 4-6 left and 4-5 right marginal rows, and 8-10 dorsal kineties; 15-83 macronuclear nodules and 2-9 micronuclei; freshwater habitat. The main morphogenetic developments are: (1) the oral primordium for the proter originates de novo on the dorsal wall of the buccal cavity, and the dedifferentiated undulating membranes and some parental proximal membranelles join in the primordial development; the old adoral zone will be partly replaced by new structures; (2) the oral primordium for the opisthe occurs epiapokinetally left of the midventral complex between the adoral zone and the transverse cirri; (3) the fronto-midventral transverse cirral (FVT) anlagen develop separately in both dividers by dedifferentiation of most of the midventral cirri; (4) the single buccal cirrus is generated from the posterior end of FVT anlage II; (5) the leftmost frontal cirrus is derived from the anterior end of the undulating membranes anlage (FVT anlage I); (6) the marginal rows of each side are formed from a single anlage which arises within the rightmost row; (7) the dorsal kineties develop by intrakinetal basal body proliferation; and (8) the most posterior FVT anlage contributes the two

  3. Cellular Taxonomy of the Mouse Striatum as Revealed by Single-Cell RNA-Seq.

    Science.gov (United States)

    Gokce, Ozgun; Stanley, Geoffrey M; Treutlein, Barbara; Neff, Norma F; Camp, J Gray; Malenka, Robert C; Rothwell, Patrick E; Fuccillo, Marc V; Südhof, Thomas C; Quake, Stephen R

    2016-07-26

    The striatum contributes to many cognitive processes and disorders, but its cell types are incompletely characterized. We show that microfluidic and FACS-based single-cell RNA sequencing of mouse striatum provides a well-resolved classification of striatal cell type diversity. Transcriptome analysis revealed ten differentiated, distinct cell types, including neurons, astrocytes, oligodendrocytes, ependymal, immune, and vascular cells, and enabled the discovery of numerous marker genes. Furthermore, we identified two discrete subtypes of medium spiny neurons (MSNs) that have specific markers and that overexpress genes linked to cognitive disorders and addiction. We also describe continuous cellular identities, which increase heterogeneity within discrete cell types. Finally, we identified cell type-specific transcription and splicing factors that shape cellular identities by regulating splicing and expression patterns. Our findings suggest that functional diversity within a complex tissue arises from a small number of discrete cell types, which can exist in a continuous spectrum of functional states.

  4. Cellular Taxonomy of the Mouse Striatum as Revealed by Single-Cell RNA-Seq

    Directory of Open Access Journals (Sweden)

    Ozgun Gokce

    2016-07-01

    Full Text Available The striatum contributes to many cognitive processes and disorders, but its cell types are incompletely characterized. We show that microfluidic and FACS-based single-cell RNA sequencing of mouse striatum provides a well-resolved classification of striatal cell type diversity. Transcriptome analysis revealed ten differentiated, distinct cell types, including neurons, astrocytes, oligodendrocytes, ependymal, immune, and vascular cells, and enabled the discovery of numerous marker genes. Furthermore, we identified two discrete subtypes of medium spiny neurons (MSNs that have specific markers and that overexpress genes linked to cognitive disorders and addiction. We also describe continuous cellular identities, which increase heterogeneity within discrete cell types. Finally, we identified cell type-specific transcription and splicing factors that shape cellular identities by regulating splicing and expression patterns. Our findings suggest that functional diversity within a complex tissue arises from a small number of discrete cell types, which can exist in a continuous spectrum of functional states.

  5. Ruminal degradability and ciliates protozoa population in rumen of Nellore steers fed with high concentrated diet supplemented with live yeast, monensin and salinomycin

    Directory of Open Access Journals (Sweden)

    Josiane Hernades Ortolan

    2010-01-01

    Full Text Available Four Nelore steers had been used, with average alive weight of 190±32 kg, in experimental delineation by 4x4 latin square, whith the objective of evaluate the effect of the yeast monensin and salinomycin on the parameters of ruminal degradability and the ciliates protozoa population present in the animals rumen. The diet offered to the animals was composed by sorghum silage and concentrated (30:70, respectively, where the four different treatments had been submitted in accordance with the used additive: 5,0g of yeast culture (Beef Sacc®; 0.42g of salinomycin (Coxistac®; 2.0g of monensin (Rumensin® and the control, without additive. The experimental period was subdivided in 21 days of adaptation and seven of harvest, totalized 28 days of experimental period. It had increase of the value for fraction “b” in the dry matter, the treatment with yeast culture, and the salinomycin treatment (P<0,05. The treatment with yeast significantly increased the number of rumen ciliates protozoa (P<0,05.

  6. The Anti-Oxidant Defense System of the Marine Polar Ciliate Euplotes nobilii: Characterization of the MsrB Gene Family

    Directory of Open Access Journals (Sweden)

    Francesca Ricci

    2017-01-01

    Full Text Available Organisms living in polar waters must cope with an extremely stressful environment dominated by freezing temperatures, high oxygen concentrations and UV radiation. To shed light on the genetic mechanisms on which the polar marine ciliate, Euplotes nobilii, relies to effectively cope with the oxidative stress, attention was focused on methionine sulfoxide reductases which repair proteins with oxidized methionines. A family of four structurally distinct MsrB genes, encoding enzymes specific for the reduction of the methionine-sulfoxide R-forms, were identified from a draft of the E. nobilii transcriptionally active (macronuclear genome. The En-MsrB genes are constitutively expressed to synthesize proteins markedly different in amino acid sequence, number of CXXC motifs for zinc-ion binding, and presence/absence of a cysteine residue specific for the mechanism of enzyme regeneration. The En-MsrB proteins take different localizations in the nucleus, mitochondria, cytosol and endoplasmic reticulum, ensuring a pervasive protection of all the major subcellular compartments from the oxidative damage. These observations have suggested to regard the En-MsrB gene activity as playing a central role in the genetic mechanism that enables E. nobilii and ciliates in general to live in the polar environment.

  7. Different Cell Types In the Lower Respiratory Tract of the Reindeer (Rangifer tarandus tarandus L. - A Transmission Electron Microscopical Study

    Directory of Open Access Journals (Sweden)

    Seppo A.m. Saari

    1997-02-01

    Full Text Available The epithelium of the trachea and distal airways of 12 healthy adult reindeer were studied with transmission electron microscopy. The ultrastructure of the reindeer respiratory tract corresponded to the findings of previous investigators studying other mammalian species. The epithelium of the trachea and bronchi, down to the level of the distal bronchioli, was composed of three main types of cell: ciliated, goblet, and basal. In the distal brochioli, non-ciliated cells similar to those known as Clara cells were predominant. Numerous electron-dense granules and the cell organelle pattern resembled the Clara cell type observed in laboratory rodents, rabbit, sheep, pig, horse, and llama. Pneumocyte 1 and pneumocyte 2 cells were readily identified in the alveoli. The pneumocyte 2 cells possessed short microvilli and granules with lamellar content. Micropinocytotic vesicles were very numerous in the alveolar wall, and a small number of alveolar macrophages occasionally seen in the alveolar lumen.

  8. Separate Culture and Morphological Observation of Free Living Amoebae and Ciliates%自生阿米巴和纤毛虫的分离培养与观察

    Institute of Scientific and Technical Information of China (English)

    岳爱梅; 刘营; 谭叶; 丛慧; 林佳慧; 张英杰; 张忠广

    2013-01-01

    Objective To study the methods of cultivation and morphological observation of free living amoebae and ciliates and observe the growth and species change of parasites in different time and vegetables. Methods Various green vegetable juice were prepared for cultivating the amoebae and ciliates at 37℃ The growth of free living amoebae and ciliates were observed using microscope. Results Rotary motion of ciliates was observed after cultivation for 48 hours.Decreased quantity and activity of ciliates and increased quantity and activity of free living amoebae were observed after cultivation for 72 hours. Decreased quantity of free living amoebae and ciliates were observed even disappeared but the cysts appeared after cultivation for 144 hours. And various green vegetable juice showed differences in culturing the amoebae and ciliates; between 72 h to 120 h ciliates could be found in celery juice, while free living amoebae were found between 96 h to 120 h. Ciliates could be easier to observe in rape flower juice between 72 h to 96h and free living amoebae easier to see in caraway juice between 72 h to 120 h. Conclusion This method is simple and convenient to observe the living amoebae and ciliates. It is useful in the parasitology teaching.%目的 研究建立自生阿米巴和纤毛虫的培养方法,观察不同菜种在不同时间寄生虫的生长情况及种类的变化.方法 制作不同蔬菜叶的悬液,37℃恒温培养,镜下观察不同时间自生阿米巴和纤毛虫的生长情况.结果 培养48 h后,可观察到纤毛虫活跃的旋转运动;72 h后纤毛虫数量减少,活动度降低,自生阿米巴出现,蠕动活跃;144 h后自生阿米巴、纤毛虫数量减少甚至观察不到,包囊出现,不同菜种在不同时间自生阿米巴、纤毛虫数量、种类也相应变化,如芹菜中纤毛虫在72~120 h、阿米巴在96~120 h数量最多,最易观察到,油菜中纤毛虫在72~96 h最易观察到,香菜中阿米巴在72~120 h

  9. Nestin-positive cells in the spinal cord: a potential source of neural stem cells.

    Science.gov (United States)

    Xu, Renshi; Wu, Chengsi; Tao, Yuhui; Yi, Juan; Yang, Yunzhu; Zhang, Xiong; Liu, Rugao

    2008-11-01

    Some literatures have reported neural precursor cells (NPCs) exist in spinal cord of adult mammal, however, the NPCs distribution feature in spinal cord of adult mice so far is not described in detail. In order to observe and compare the distribution feature of NPCs in various spinal cord regions of adult mice, to research a potential source of neural stem cells (NSCs), we obtained NPCs distribution feature by analyzing the distribution of the nestin-containing cells (NCCs) in spinal cord of adult nestin second-intron enhancer controlled LacZ reporter transgenic mice (pNes-Tg) with LacZ staining and positive cell quantification. The results showed that: NCCs were observed in various regions of spinal cord of adult mice, but amount of NCCs was different in distinct region, the rank order of NCCs amount in various spinal cord regions was dorsal horn region greater than central canal greater than the ventral and lateral horn. NCCs in dorsal horn region mainly distributed in substantia gelatinosa, NCCs in central canal mainly distributed in ependymal zone, on the contrary, NCCs in ventral, lateral horn, medullae, nucleus regions of spinal cord were comparatively less. The rank order of NCCs amount in various spinal cord segments was cervical segment greater than lumbar sacral segment greater than thoracic segment. There was no significantly difference between NCCs amount in the left and right sides, and within cervical 1-7, thoracic 1-12, lumbar 1-5, sacral segment of spinal cord in adult mice. These data collectively indicate that NPCs extensively distribute in various regions of spinal cord of adult mice, especially in substantia gelatinosa and ependymal zone. NPCs in cervical segment are abundant, NPCs in thoracic segment are the least while compared the different spinal cord segment, the NPCs in various regions of spinal cord of adult mice are a potential source of NSCs.

  10. A case study for effects of operational taxonomic units from intracellular endoparasites and ciliates on the eukaryotic phylogeny: phylogenetic position of the haptophyta in analyses of multiple slowly evolving genes.

    Directory of Open Access Journals (Sweden)

    Hisayoshi Nozaki

    Full Text Available Recent multigene phylogenetic analyses have contributed much to our understanding of eukaryotic phylogeny. However, the phylogenetic positions of various lineages within the eukaryotes have remained unresolved or in conflict between different phylogenetic studies. These phylogenetic ambiguities might have resulted from mixtures or integration from various factors including limited taxon sampling, missing data in the alignment, saturations of rapidly evolving genes, mixed analyses of short- and long-branched operational taxonomic units (OTUs, intracellular endoparasite and ciliate OTUs with unusual substitution etc. In order to evaluate the effects from intracellular endoparasite and ciliate OTUs co-analyzed on the eukaryotic phylogeny and simplify the results, we here used two different sets of data matrices of multiple slowly evolving genes with small amounts of missing data and examined the phylogenetic position of the secondary photosynthetic chromalveolates Haptophyta, one of the most abundant groups of oceanic phytoplankton and significant primary producers. In both sets, a robust sister relationship between Haptophyta and SAR (stramenopiles, alveolates, rhizarians, or SA [stramenopiles and alveolates] was resolved when intracellular endoparasite/ciliate OTUs were excluded, but not in their presence. Based on comparisons of character optimizations on a fixed tree (with a clade composed of haptophytes and SAR or SA, disruption of the monophyly between haptophytes and SAR (or SA in the presence of intracellular endoparasite/ciliate OTUs can be considered to be a result of multiple evolutionary reversals of character positions that supported the synapomorphy of the haptophyte and SAR (or SA clade in the absence of intracellular endoparasite/ciliate OTUs.

  11. Rumen ciliates in the African (Cape) buffalo (Syncerus caffer caffer) living in the vicinity of the Orpen Gate entrance into Kruger National Park, South Africa.

    Science.gov (United States)

    Booyse, Dirk G; Dehority, Burk A; Reininghaus, Björn

    2014-07-31

    Samples of rumen contents were obtained from 10 African (Cape) buffalo living in the vicinity of the Orpen Gate entrance into Kruger National Park in South Africa. Total number of ciliate protozoa per animal ranged from 3.15 to 23.25 x 103. Forty three different species and forms were observed, of which 35 are a new host record. The total number of species and forms per animal varied from 10 to 17. Eudiplodinium maggii occurred in all 10 animals, followed by Dasytricha ruminantium in nine animals. Diplodinium posterovesiculatum, Eudiplodinium magnodentatum and Ostracodinium mammosum were present in seven animals with all other species and forms occurring in five or less animals. 

  12. ParameciumDB in 2011: new tools and new data for functional and comparative genomics of the model ciliate Paramecium tetraurelia.

    Science.gov (United States)

    Arnaiz, Olivier; Sperling, Linda

    2011-01-01

    ParameciumDB is a community model organism database built with the GMOD toolkit to integrate the genome and biology of the ciliate Paramecium tetraurelia. Over the last four years, post-genomic data from proteome and transcriptome studies has been incorporated along with predicted orthologs in 33 species, annotations from the community and publications from the scientific literature. Available tools include BioMart for complex queries, GBrowse2 for genome browsing, the Apollo genome editor for expert curation of gene models, a Blast server, a motif finder, and a wiki for protocols, nomenclature guidelines and other documentation. In-house tools have been developed for ontology browsing and evaluation of off-target RNAi matches. Now ready for next-generation deep sequencing data and the genomes of other Paramecium species, this open-access resource is available at http://paramecium.cgm.cnrs-gif.fr.

  13. Temporal variability of the microbial food web (viruses to ciliates under the influence of the Black Sea Water inflow (N. Aegean, E. Mediterranean

    Directory of Open Access Journals (Sweden)

    A. GIANNAKOUROU

    2015-01-01

    Full Text Available Τhe entire pelagic microbial food web was studied during the winter-spring period in the frontal area of the North Aegean Sea. Abundance of viruses, heterotrophic bacteria, cyanobacteria, auto- and hetero-trophic flagellates, and ciliates, as well as bacterial production, were measured at three stations (MD1, MD2, MD3 situated along a N-S transect between the area directly influenced by the inflowing Black Sea water and the area covered by the Levantine water. Samples were collected in December 2009, and January, March, April, and May 2011. Station MD1 exhibited the highest values of abundance and integrated biomass of all microbial groups and bacterial production during all months, and MD3 the lowest. Bacteria dominated the total integrated biomass at all stations and months, followed by cyanobacteria, auto-, hetero-trophic flagellates and ciliates. On a temporal scale, the microbial food web was less important in March as all microbial parameters at all stations showed the lowest values. After the phytoplankton bloom in March, the heterotrophic part of the microbial food web (mainly strongly increased, though the intensity of the phenomenon was diminished from North to South. Pico-sized plankton was found to be heterotrophic whereas nanoplankton was autotrophic. It seems that the influence of the Black Sea water on station MD1, permanent throughout the study period of early winter to late spring, was reflected in all microbial populations studied, and produced a more productive pelagic food web system, with potential consequences for the upper trophic levels.

  14. Effect of high levels of the rotifer Lecane inermis on the ciliate community in laboratory-scale sequencing batch bioreactors (SBRs).

    Science.gov (United States)

    Fyda, Janusz; Babko, Roman; Fiałkowska, Edyta; Pajdak-Stós, Agnieszka; Kocerba-Soroka, Wioleta; Sobczyk, Mateusz; Sobczyk, Łukasz

    2015-10-01

    Due to its ability to feed on filamentous bacteria, the rotifer Lecane inermis has already been recognized as a potential control agent of activated sludge bulking, which is usually caused by the excessive growth of filamentous microorganisms. However, their effectiveness depends, in part, on their abundance. We studied the influence of high densities of L. inermis on the protozoan community in activated sludge from a wastewater treatment plant (WWTP) in 4 laboratory-scale sequencing batch bioreactors (SBRs). Two treatments and two controls were subjected to nutrient removal system in process similar to that used in a WWTP. The experiment lasted 9 days and was repeated in 24-h cycles, including phases of agitation with feeding, aeration and agitation and sedimentation with decantation at the end of the cycle. In total, 32 taxa were identified, among which 25 were ciliated protozoa, 4 were amoebae, 2 were flagellates, and one was a nematode. Rotifers were then introduced to 2 bioreactors at a final concentration of 500ind.mL(-1), and the taxonomic composition and abundance of the activated sludge microfauna were assessed 2, 5 and 8 days thereafter. The mean density of ciliates on the first day of experiment was 12,610ind.mL(-1) and diminished to 4868±432ind.mL-±432ind.mL(-1) in the control and 5496±638ind.mL(-1) in the rotifer-treated group on the last day. Thus, even extremely high densities of artificially introduced rotifers did not negatively affect the protozoan community. On the contrary, the protozoan community was more diverse in the treatment group than in the control.

  15. Crypt cells are involved in kin recognition in larval zebrafish

    Science.gov (United States)

    Biechl, Daniela; Tietje, Kristin; Gerlach, Gabriele; Wullimann, Mario F.

    2016-01-01

    Zebrafish larvae imprint on visual and olfactory kin cues at day 5 and 6 postfertilization, respectively, resulting in kin recognition later in life. Exposure to non-kin cues prevents imprinting and kin recognition. Imprinting depends on MHC class II related signals and only larvae sharing MHC class II alleles can imprint on each other. Here, we analyzed which type of olfactory sensory neuron (OSN) detects kin odor. The single teleost olfactory epithelium harbors ciliated OSNs carrying OR and TAAR gene family receptors (mammals: main olfactory epithelium) and microvillous OSNs with V1R and V2R gene family receptors (mammals: vomeronasal organ). Additionally, teleosts exhibit crypt cells which possess microvilli and cilia. We used the activity marker pERK (phosphorylated extracellular signal regulated kinase) after stimulating 9 day old zebrafish larvae with either non-kin conspecific or food odor. While food odor activated both ciliated and microvillous OSNs, only the latter were activated by conspecific odor, crypt cells showed no activation to both stimuli. Then, we tested imprinted and non-imprinted larvae (full siblings) for kin odor detection. We provide the first direct evidence that crypt cells, and likely a subpopulation of microvillous OSNs, but not ciliated OSNs, play a role in detecting a kin odor related signal. PMID:27087508

  16. A New Method of Sample Preparation for Scanning Electron Microscope Used to Observe the Structure under Pellicle in Ciliates%一种用于观察纤毛虫表膜下结构的扫描电镜样品制备新方法

    Institute of Scientific and Technical Information of China (English)

    高晶; 周围; 乔良; 陈瑛; 邱子健

    2011-01-01

    A new method of observing three-dimensional structure under pellicle of ciliates by scanning electron microscope was established. The suitable concentration of KMnO4 was used to fix cell pellicle. The cell bursts and the cytoplasm overflows in the hypotonic solution by adjusting the osmotic pressure of fixative. Then the pellicle peels off and the inside out. After removing the cytoplasm and dehydration, freeze drying and spraying gold, the structure under pellicle was observed by scanning electron microscope in Climacostomum sp., Parame-cium caudatum and Paraurostyla weissei. The result shows that a clearly and stratified three-dimensional images of structure under pellicle can be observed by this method. It could provide a new way for the study on the pellicle of ciliates and other cell memberanes.%该实验摸索出通过扫描电镜观察纤毛虫表膜下三维结构的新方法:用适当浓度的KMnO4作为固定剂,固定虫体细胞表膜,调整固定液的渗透压使细胞在低渗溶液中胀破,细胞质溶出,表膜剥落下来、内外翻转,经脱水、冷冻干燥、喷金后,在扫描电镜下对爽口虫(Climacostomum sp.)、尾草履虫(Paramecium caudatum)及拟尾柱虫(Paraurostyla weissei)的表膜下结构进行了观察.结果表明:利用此方法能够观察到表膜下层次分明而又清晰的三维立体构象.此方法可为纤毛虫表膜及其它细胞质膜的研究提供可借鉴的样品制备新方法.

  17. The human airway epithelial basal cell transcriptome.

    Directory of Open Access Journals (Sweden)

    Neil R Hackett

    Full Text Available BACKGROUND: The human airway epithelium consists of 4 major cell types: ciliated, secretory, columnar and basal cells. During natural turnover and in response to injury, the airway basal cells function as stem/progenitor cells for the other airway cell types. The objective of this study is to better understand human airway epithelial basal cell biology by defining the gene expression signature of this cell population. METHODOLOGY/PRINCIPAL FINDINGS: Bronchial brushing was used to obtain airway epithelium from healthy nonsmokers. Microarrays were used to assess the transcriptome of basal cells purified from the airway epithelium in comparison to the transcriptome of the differentiated airway epithelium. This analysis identified the "human airway basal cell signature" as 1,161 unique genes with >5-fold higher expression level in basal cells compared to differentiated epithelium. The basal cell signature was suppressed when the basal cells differentiated into a ciliated airway epithelium in vitro. The basal cell signature displayed overlap with genes expressed in basal-like cells from other human tissues and with that of murine airway basal cells. Consistent with self-modulation as well as signaling to other airway cell types, the human airway basal cell signature was characterized by genes encoding extracellular matrix components, growth factors and growth factor receptors, including genes related to the EGF and VEGF pathways. Interestingly, while the basal cell signature overlaps that of basal-like cells of other organs, the human airway basal cell signature has features not previously associated with this cell type, including a unique pattern of genes encoding extracellular matrix components, G protein-coupled receptors, neuroactive ligands and receptors, and ion channels. CONCLUSION/SIGNIFICANCE: The human airway epithelial basal cell signature identified in the present study provides novel insights into the molecular phenotype and biology of

  18. 三聚氰胺对纤毛类原生动物梨形四膜虫的细胞毒性%Cytotoxicity Assessment of Melamine Using the Ciliated Protozoan Tetrahymena pyriforrnis

    Institute of Scientific and Technical Information of China (English)

    王正方; 齐小花; 邹明强; 张卓勇; 徐芳

    2009-01-01

    三聚氰胺曾被用为牛类的非蛋白类氮源,并被非法掺入食品中从而提高其表观蛋白含量.实验利用一种单细胞真核生物模型--纤毛类原生动物梨形四膜虫(Tetrahymena pyriformis)研究了三聚氰胺的细胞毒性.结果显示,三聚氰胺对梨形四膜虫的生长速率具有抑制作用,并且这种抑制作用与三聚氰胺浓度成正相关性,其IC50值为0.78g·L-1.细胞同时发生形变.实验证明梨形四膜虫生物测定法相对于动物实验具有耗时短、成本低、操作简便的优势,在潜在毒性物质的风险性评估实验中可成为一种优良的替代模型.%Melamine was once used as a non-protein nitrogen(NPN)source for cattle,and unethically added to food productions in order to increase the apparent protein content.In this study,the cytotoxicological impact of melamine was determined using a unicellular eukaryote bioassay model,the ciliated protozoan Tetrahymena pyriformis(T.pyriformis).The results showed a concentration-dependent inhibitory effect of melamine on the cell proliferation rate of T.pyriformis populations,and the IC50 value was estimated to be 0.78g·L-1.Deformed cells were also observed.Our experiment demonstrated that T. pyriformis bioassay,with advantages such as less time-consuming,lower cost and simpler operations,provides a good alternative in vitro method to animal experiments for the risk assessment of potentially toxic substances.

  19. Shaping the nervous system: role of the core planar cell polarity genes.

    Science.gov (United States)

    Tissir, Fadel; Goffinet, André M

    2013-08-01

    Planar cell polarity (PCP) is complementary to the intrinsic polarization of single cells and refers to the global coordination of cell behaviour in the plane of a tissue and, by extension, to the signalling pathways that control it. PCP is most evident in cell sheets, and research into PCP was for years confined to studies in Drosophila melanogaster. However, PCP has more recently emerged as an important phenomenon in vertebrates, in which it regulates various developmental processes and is associated with multiple disorders. In particular, core PCP genes are crucial for the development and function of the nervous system. They are involved in neural tube closure, ependymal polarity, neuronal migration, dendritic growth and axon guidance.

  20. Dystroglycan Suppresses Notch to Regulate Stem Cell Niche Structure and Function in the Developing Postnatal Subventricular Zone.

    Science.gov (United States)

    McClenahan, Freyja K; Sharma, Himanshu; Shan, Xiwei; Eyermann, Christopher; Colognato, Holly

    2016-09-12

    While the extracellular matrix (ECM) is known to regulate neural stem cell quiescence in the adult subventricular zone (SVZ), the function of ECM in the developing SVZ remains unknown. Here, we report that the ECM receptor dystroglycan regulates a unique developmental restructuring of ECM in the early postnatal SVZ. Dystroglycan is furthermore required for ependymal cell differentiation and assembly of niche pinwheel structures, at least in part by suppressing Notch activation in radial glial cells, which leads to the increased expression of MCI, Myb, and FoxJ1, transcriptional regulators necessary for acquisition of the multiciliated phenotype. Dystroglycan also regulates perinatal radial glial cell proliferation and transition into intermediate gliogenic progenitors, such that either acute or constitutive loss of function in dystroglycan results in increased oligodendrogenesis. These findings reveal a role for dystroglycan in orchestrating both the assembly and function of the SVZ neural stem cell niche.

  1. The V-ATPase accessory protein Atp6ap1b mediates dorsal forerunner cell proliferation and left-right asymmetry in zebrafish.

    Science.gov (United States)

    Gokey, Jason J; Dasgupta, Agnik; Amack, Jeffrey D

    2015-11-01

    Asymmetric fluid flows generated by motile cilia in a transient 'organ of asymmetry' are involved in establishing the left-right (LR) body axis during embryonic development. The vacuolar-type H(+)-ATPase (V-ATPase) proton pump has been identified as an early factor in the LR pathway that functions prior to cilia, but the role(s) for V-ATPase activity are not fully understood. In the zebrafish embryo, the V-ATPase accessory protein Atp6ap1b is maternally supplied and expressed in dorsal forerunner cells (DFCs) that give rise to the ciliated organ of asymmetry called Kupffer's vesicle (KV). V-ATPase accessory proteins modulate V-ATPase activity, but little is known about their functions in development. We investigated Atp6ap1b and V-ATPase in KV development using morpholinos, mutants and pharmacological inhibitors. Depletion of both maternal and zygotic atp6ap1b expression reduced KV organ size, altered cilia length and disrupted LR patterning of the embryo. Defects in other ciliated structures-neuromasts and olfactory placodes-suggested a broad role for Atp6ap1b during development of ciliated organs. V-ATPase inhibitor treatments reduced KV size and identified a window of development in which V-ATPase activity is required for proper LR asymmetry. Interfering with Atp6ap1b or V-ATPase function reduced the rate of DFC proliferation, which resulted in fewer ciliated cells incorporating into the KV organ. Analyses of pH and subcellular V-ATPase localizations suggested Atp6ap1b functions to localize the V-ATPase to the plasma membrane where it regulates proton flux and cytoplasmic pH. These results uncover a new role for the V-ATPase accessory protein Atp6ap1b in early development to maintain the proliferation rate of precursor cells needed to construct a ciliated KV organ capable of generating LR asymmetry.

  2. SDF1 in the dorsal corticospinal tract promotes CXCR4+ cell migration after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Jung Hosung

    2011-02-01

    Full Text Available Abstract Background Stromal cell-derived factor-1 (SDF1 and its major signaling receptor, CXCR4, were initially described in the immune system; however, they are also expressed in the nervous system, including the spinal cord. After spinal cord injury, the blood brain barrier is compromised, opening the way for chemokine signaling between these two systems. These experiments clarified prior contradictory findings on normal expression of SDF1 and CXCR4 as well as examined the resulting spinal cord responses resulting from this signaling. Methods These experiments examined the expression and function of SDF1 and CXCR4 in the normal and injured adult mouse spinal cord primarily using CXCR4-EGFP and SDF1-EGFP transgenic reporter mice. Results In the uninjured spinal cord, SDF1 was expressed in the dorsal corticospinal tract (dCST as well as the meninges, whereas CXCR4 was found only in ependymal cells surrounding the central canal. After spinal cord injury (SCI, the pattern of SDF1 expression did not change rostral to the lesion but it disappeared from the degenerating dCST caudally. By contrast, CXCR4 expression changed dramatically after SCI. In addition to the CXCR4+ cells in the ependymal layer, numerous CXCR4+ cells appeared in the peripheral white matter and in the dorsal white matter localized between the dorsal corticospinal tract and the gray matter rostral to the lesion site. The non-ependymal CXCR4+ cells were found to be NG2+ and CD11b+ macrophages that presumably infiltrated through the broken blood-brain barrier. One population of macrophages appeared to be migrating towards the dCST that contains SDF1 rostral to the injury but not towards the caudal dCST in which SDF1 is no longer present. A second population of the CXCR4+ macrophages was present near the SDF1-expressing meningeal cells. Conclusions These observations suggest that attraction of CXCR4+ macrophages is part of a programmed response to injury and that modulation of the

  3. Ciliate and mesozooplankton community response to increasing CO2 levels in the Baltic Sea: insights from a large-scale mesocosm experiment

    Science.gov (United States)

    Lischka, Silke; Bach, Lennart T.; Schulz, Kai-Georg; Riebesell, Ulf

    2017-01-01

    Community approaches to investigating ocean acidification (OA) effects suggest a high tolerance of micro- and mesozooplankton to carbonate chemistry changes expected to occur within this century. Plankton communities in the coastal areas of the Baltic Sea frequently experience pH variations partly exceeding projections for the near future both on a diurnal and seasonal basis. We conducted a large-scale mesocosm CO2 enrichment experiment ( ˜ 55 m3) enclosing the natural plankton community in Tvärminne-Storfjärden for 8 weeks during June-August 2012 and studied community and species-taxon response of ciliates and mesozooplankton to CO2 elevations expected for this century. In addition to the response to fCO2, we also considered temperature and chlorophyll a variations in our analyses. Shannon diversity of ciliates significantly decreased with fCO2 and temperature with a greater dominance of smaller species. The mixotrophic Myrionecta rubra seemed to indirectly and directly benefit from higher CO2 concentrations in the post-bloom phase through increased occurrence of picoeukaryotes (most likely Cryptophytes) and Dinophyta at higher CO2 levels. With respect to mesozooplankton, we did not detect significant effects for either total abundance or for Shannon diversity. The cladocera Bosmina sp. occurred at distinctly higher abundance for a short time period during the second half of the experiment in three of the CO2-enriched mesocosms except for the highest CO2 level. The ratio of Bosmina sp. with empty to embryo- or resting-egg-bearing brood chambers, however, was significantly affected by CO2, temperature, and chlorophyll a. An indirect CO2 effect via increased food availability (Cyanobacteria) stimulating Bosmina sp. reproduction cannot be ruled out. Although increased regenerated primary production diminishes trophic transfer in general, the presence of organisms able to graze on bacteria such as cladocerans may positively impact organic matter transfer to higher

  4. Abundância de ciliados planctônicos em reservatórios em cascata do rio Paranapanema, Brasil- DOI: 10.4025/actascibiolsci.v26i4.1532 Abundance of planktonic ciliates in a cascading reservoirs of the Paranapanema River, Brazil - DOI: 10.4025/actascibiolsci.v26i4.1532

    Directory of Open Access Journals (Sweden)

    Maysa Cláudia Zolin Perenha

    2004-04-01

    of the lacustrine region, using a Van Dorn bottle (5 liters. Aliquots from one liter were obtained and fixed with a fixing solution compounded by alkaline lugol, formaldehyde and sodium tiosulfate. Obtained values for ciliates abundance (density and biomass in different reservoirs (0.4 to 16.6 cells.mL-1; 0.23 to 20.7 µg.C.L-1, respectively were inferior to results found in eutrophic environments, but similar to those registered in oligo-mesotrophic environments. Analysis of the abundance distribution results, along reservoirs serie, did not corroborate the hypothesis of decreasing density and biomass from upstream to dowstream, due to an expectancy of a possible oligotrophication downriver. In relation to different functional groups of ciliates, it was verified the dominance of Oligotrichida, mainly small sized individuals (< 30 µm.

  5. Cilia containing 9 + 2 structures grown from immortalized cells

    Institute of Scientific and Technical Information of China (English)

    Ming Zhang; Jose G Assouline

    2007-01-01

    Cilia depend on their highly differentiated structure, a 9 + 2 arrangement, to remove particles from the lung and to transport reproductive cells. Immortalized cells could potentially be of great use in cilia research. Immortalization of cells with cilia structure containing the 9 + 2 arrangement might be able to generate cell lines with such cilia structure. However, whether immortalized cells can retain such a highly differentiated structure remains unclear. Here we demonstrate that (1) using E1a gene transfection, tracheal cells are immortalized; (2) interestingly, in a gel culture the immortalized cells form spherical aggregations within which a lumen is developed; and (3) surprisingly, inside the aggregation, cilia containing a 9 + 2 arrangement grow from the cell's apical pole and protrude into the lumen. These results may influence future research in many areas such as understanding the mechanisms of cilia differentiation, cilia generation in other existing cell lines, cilia disorders, generation of other highly differentiated structures besides cilia using the gel culture,immortalization of other ciliated cells with the E1a gene, development of cilia motile function, and establishment of a research model to provide uniform ciliated cells.

  6. Sulphur-cycling bacteria and ciliated protozoans in a Beggiatoaceae mat covering organically enriched sediments beneath a salmon farm in a southern Chilean fjord.

    Science.gov (United States)

    Aranda, Carlos P; Valenzuela, Cristian; Matamala, Yessica; Godoy, Félix A; Aranda, Nicol

    2015-11-15

    The colourless mat covering organically enriched sediments underlying an intensive salmon farm in Estero Pichicolo, southern Chile, was surveyed by combined 454 PyroTag and conventional Sanger sequencing of 16S/18S ribosomal RNA genes for Bacteria and Eukarya. The mat was dominated by the sulphide-oxidizing bacteria (SOB) Candidatus Isobeggiatoa, Candidatus Parabeggiatoa and Arcobacter. By order of their abundances, sulphate-reducing bacteria (SRB) were represented by diverse deltaproteobacterial Desulfobacteraceae, but also within Desulfobulbaceae, Desulfuromonadaceae and Desulfovibrionaceae. The eukaryotic PyroTags were dominated by polychaetes, copepods and nematodes, however, ciliated protozoans were highly abundant in microscopy observations, and were represented by the genera Condylostoma, Loxophyllum and Peritromus. Finally, the abundant Sulfurimonas/Sulfurovum also suggest the occurrence of zero-valence sulphur oxidation, probably derived from Beggiatoaceae as a result of bacteriovorus infaunal activity or generated as free S(0) by the Arcobacter bacteria. The survey suggests an intense and complex sulphur cycle within the surface of salmon-farm impacted sediments.

  7. The use of protozoa in ecotoxicology: application of multiple endpoint tests of the ciliate E. crassus for the evaluation of sediment quality in coastal marine ecosystems.

    Science.gov (United States)

    Gomiero, A; Dagnino, A; Nasci, C; Viarengo, A

    2013-01-01

    Despite an increasing number of surveys describing adverse effects of contaminated sediments on marine organisms, few studies have addressed protists. In this study, the free-crawling marine ciliate Euplotes crassus was evaluated as the test organism for the screening of sediment toxicity using sediments from both coastal and estuarine sites of the Venice Lagoon (Marghera harbour [MH], Valle Millecampi [MV], Murano island [MI] and Lido inlet [LI]). Two endpoints of high ecological value, mortality (Mry) and replication rate (RpR), were assessed in combination with the two sublethal biomarkers of stress, endocytotic rate (Ecy) and lysosomal membrane stability (NRRT). The results showed a significant inhibition of RpR, Ecy and NRRT paralleled by a small and insignificantly increased Mry of the exposed specimens. Our results thus demonstrate that only a combination of mortality and sublethal biomarkers was able to characterise an exposure-related stress syndrome. The suite of biomarkers described here was also able to detect and resolve a pollution-induced stress syndrome at an early stage of pollution. The contamination level of the sediments was assessed using chemical analysis, by estimating bioavailability and by computing a toxic pressure coefficient (TPC) to account for potential additive effects of different pollutants. The observed biological responses were consistent with the contamination levels in sediments, suggesting a high potential for using Protozoa in bioassays to assess environmental risk in coastal marine systems.

  8. Phylogeny and establishment of a new ciliate family, Wilbertomorphidae fam. nov. (Ciliophora, Karyorelictea), a highly specialized taxon represented by Wilbertomorpha colpoda gen. nov., spec. nov.

    Science.gov (United States)

    Xu, Yuan; Li, Jiamei; Song, Weibo; Warren, Alan

    2013-01-01

    The morphology and molecular phylogeny of a new marine interstitial karyorelictean ciliate, Wilbertomorpha colpoda gen. nov., spec. nov., isolated from a sandy beach at Qingdao, China, are investigated. The ciliature is mainly on the right surface with the left surface barren except for a single marginal kinety, which is typical of the order Loxodida. Nevertheless, other morphological features, such as the highly reduced buccal structure, the absence of a buccal cavity and the presence of extremely specialized cortical granules, prevent its assignation to any known family. Furthermore, the secondary structure of the variable region 2 of the SSU rRNA gene is unique among loxodids. Thus, we establish a new family, Wilbertomorphidae fam. nov. for the genus Wilbertomorpha. Phylogenetic analyses based on SSU rRNA gene sequence data suggest that this taxon is a sister group to the family Geleiidae which belongs to the order Protoheterotrichida. However, morphologically Wilbertomorpha bears a much stronger resemblance to Loxodidae which belongs to the order Loxodida. Based on these findings, we tentatively place Wilbertomorphidae nov. fam. incertae sedis within Karyorelictea.

  9. 纤毛类原生动物中宿主-共生体系统的研究%Studies on the Host-Symbiont System in Ciliates

    Institute of Scientific and Technical Information of China (English)

    顾福康; 孙军; 何远; 田沁

    2001-01-01

    目前已经在100多种纤毛虫中观察到细菌、藻类和其他微生物等共生体。对纤毛虫中宿主-共生体系统的研究表明,双小核草履虫中卡巴粒的遗传为细胞质遗传理论提供了例证;含细菌共生体的许多厌氧纤毛虫无线粒体,共生体对宿主代谢有重要作用;尾草履虫-钝状全孢螺菌共生作用中,共生菌感染形式的39kDa、15kDa周质蛋白可分别与IF-3-1、IF-3-2两种单抗反应,其共生体早期感染过程中两种抗原的量发生显著变化,并且共生体生殖 形式选择性地合成63kDa蛋白质,该蛋白质可能是与共生作用有联系的关键分子;绿草履虫-小球藻共生系统中,共生藻中存在葡糖胺硬性壁是其与草履虫发生共生关系的基本条件,其中,共生藻参与宿主代谢,与宿主形成相互受益的专一性关系,并且藻类共生体的作用可能影响了宿主草履虫基因组有关结构,改变了其基因表达。作者推测,探索共生体对宿主基因结构及其表达产物的影响可能是对纤毛虫中共生作用研究的主要趋势,这对于深入了 解真核细胞中宿主-共生体双方的相互作用、物质交流在分子水平上的调控机理、细胞结构与功能的关系等细胞生命活动规律是有意义的。%To date, bacterial,algal and other microbial symbionts have been found in more than 100 species of ciliates. The study of the host-symbiont system in ciliates shows that: ( 1 ) The inheritance of kappa particles in the cytoplasm of Paramecium aurelia is a classic example of the cytoplasmic inheritance theory. (2) Bacterial symbionts in some anerobic ciliates that lack mitochondria play the major role in the host's metabolism. (3) In the P. Caudatum-Holospora obtusa system, 39- and 15-kDa periplasmic pro teins of the infectious H. Obtusa reacted with IF-3-1 and IF-3-2 monoclonal antibodies respectively. The amounts of both antigens were reduced during

  10. Morphology of four new solitary sessile peritrich ciliates from the Yellow Sea, China, with description of an unidentified species of Paravorticella (Ciliophora, Peritrichia).

    Science.gov (United States)

    Sun, Ping; Al-Farraj, Saleh A; Warren, Alan; Ma, Honggang

    2017-02-01

    Sessile peritrichs are a large assemblage of ciliates that have a wide distribution in soil, freshwater and marine waters. Here, we document four new and one unidentified species of solitary sessile peritrichs from aquaculture ponds and coastal waters of the northern Yellow Sea, China. Based on their living morphology, infraciliature and silverline system, four of the five forms were identified as new members belonging to one of three genera, Vorticella, Pseudovorticella and Scyphidia, representing two families, Vorticellidae and Scyphidiidae. The other isolate was found to be an unidentified species of the poorly known genus Paravorticella. Vorticella chiangi sp. nov. is characterized by its inverted bell-shaped zooid, short row 3 in infundibular polykinety 3 and marine habitat. Pseudovorticella liangae sp. nov. posseses a thin, broad peristomial lip and a granular pellicle. Pseudovorticella haiboensis sp. nov. is differentiated from its congeners by having an elongated zooid that is covered by a layer of thin pellicular vesicles, and two rows of kineties in infundibular polykinety 3. Scyphidia perezuzae sp. nov. and Paravorticella sp. are stalkless ectoparasites or ectocommensals of aquatic animals. The former has a short, plump body, a narrow peristomial lip and a conspicuous, flattened, disc-shaped scopula for adhesion. Paravorticella sp. has an extremely elongated clavate body, a broad peristomial lip, and a narrow scopula.

  11. Repair of tracheal epithelium by basal cells after chlorine-induced injury

    Directory of Open Access Journals (Sweden)

    Musah Sadiatu

    2012-11-01

    Full Text Available Abstract Background Chlorine is a widely used toxic compound that is considered a chemical threat agent. Chlorine inhalation injures airway epithelial cells, leading to pulmonary abnormalities. Efficient repair of injured epithelium is necessary to restore normal lung structure and function. The objective of the current study was to characterize repair of the tracheal epithelium after acute chlorine injury. Methods C57BL/6 mice were exposed to chlorine and injected with 5-ethynyl-2′-deoxyuridine (EdU to label proliferating cells prior to sacrifice and collection of tracheas on days 2, 4, 7, and 10 after exposure. Airway repair and restoration of a differentiated epithelium were examined by co-localization of EdU labeling with markers for the three major tracheal epithelial cell types [keratin 5 (K5 and keratin 14 (K14 for basal cells, Clara cell secretory protein (CCSP for Clara cells, and acetylated tubulin (AcTub for ciliated cells]. Morphometric analysis was used to measure proliferation and restoration of a pseudostratified epithelium. Results Epithelial repair was fastest and most extensive in proximal trachea compared with middle and distal trachea. In unexposed mice, cell proliferation was minimal, all basal cells expressed K5, and K14-expressing basal cells were absent from most sections. Chlorine exposure resulted in the sloughing of Clara and ciliated cells from the tracheal epithelium. Two to four days after chlorine exposure, cell proliferation occurred in K5- and K14-expressing basal cells, and the number of K14 cells was dramatically increased. In the period of peak cell proliferation, few if any ciliated or Clara cells were detected in repairing trachea. Expression of ciliated and Clara cell markers was detected at later times (days 7–10, but cell proliferation was not detected in areas in which these differentiated markers were re-expressed. Fibrotic lesions were observed at days 7–10 primarily in distal trachea. Conclusion

  12. X-ray microanalysis in cryosections of natively frozen Paramecium caudatum with regard to ion distribution in ciliates

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, M.; Meyer, R.; Zierold, K.

    1985-01-01

    Cells of Paramecium caudatum were shock-frozen without pretreatment for cryoultramicrotomy and freeze-dried for subsequent X-ray microanalysis. Na, Mg, P, S, Cl, K, and Ca were detected in different amounts in several subcellular compartments. In particular, calcium was localized below the cell surface (pellicle). Trichocysts were found to contain significant amounts of Na in their base but not in the tip. Na, Mg, P, S, Cl, K, Ca were found in electron dense deposits within the lumen of the contractile vacuole. A small K concentration was found in the cytoplasm and in the mitochondria. X-ray microanalysis of the element distribution in different subcellular compartments provides information for the understanding of cellular functions such as exocytosis, locomotion, and ion regulation.

  13. Immunohistochemical demonstration of airway epithelial cell markers of guinea pig.

    Science.gov (United States)

    Li, Yong; Wang, Jing; He, Hai Yan; Ma, Ling Jie; Zeng, Jin; Deng, Guang Cun; Liu, Xiaoming; Engelhardt, John F; Wang, Yujiong

    2011-10-01

    The guinea pig (Cavea porcellus) is a mammalian non-rodent species in the Caviidae family. The sensitivity of the respiratory system and the susceptibility to infectious diseases allows the guinea pig to be a useful model for both infectious and non-infectious lung diseases such as asthma and tuberculosis. In this report, we demonstrated for the first time, the major cell types and composition in the guinea pig airway epithelium, using cell type-specific markers by immunohistochemical staining using the commercial available immunological reagents that cross-react with guinea pig. Our results revealed the availability of antibodies cross-reacting with airway epithelial cell types of basal, non-ciliated columnar, ciliated, Clara, goblet and alveolar type II cells, as well as those cells expressing Mucin 5AC, Mucin 2, Aquaporin 4 and Calcitonin Gene Related Peptide. The distribution of these various cell types were quantified in the guinea pig airway by immunohistochemical staining and were comparable with morphometric studies using an electron microscopy assay. Moreover, this study also demonstrated that goblet cells are the main secretory cell type in the guinea pig's airway, distinguishing this species from rats and mice. These results provide useful information for the understanding of airway epithelial cell biology and mechanisms of epithelial-immune integration in guinea pig models.

  14. Role of four conserved aspartic acid residues of EF-loops in the metal ion binding and in the self-assembly of ciliate Euplotes octocarinatus centrin.

    Science.gov (United States)

    Liu, Wen; Duan, Lian; Sun, Tijian; Yang, Binsheng

    2016-12-01

    Ciliate Euplotes octocarinatus centrin (EoCen) is an EF-hand calcium-binding protein closely related to the prototypical calcium sensor protein calmodulin. Four mutants (D37K, D73K, D110K and D146K) were created firstly to elucidate the importance of the first aspartic acid residues (Asp37, Asp73, Asp110 and Asp146) in the beginning of the four EF-loops of EoCen. Aromatic-sensitized Tb(3+) fluorescence indicates that the aspartic acid residues are very important for the metal-binding of EoCen, except for Asp73 (in EF-loop II). Resonance light scattering (RLS) measurements for different metal ions (Ca(2+) and Tb(3+)) binding proteins suggest that the order of four conserved aspartic acid residues for contributing to the self-assembly of EoCen is Asp37 > Asp146 > Asp110 > Asp73. Cross-linking experiment also exhibits that Asp37 and Asp146 play critical role in the self-assembly of EoCen. Asp37, in site I, which is located in the N-terminal domain, plays the most important role in the metal ion-dependent self-assembly of EoCen, and there is cooperativity between N-terminal and C-terminal domain (especially the site IV). In addition, the dependence of Tb(3+) induced self-assembly of EoCen and the mutants on various factors, including ionic strength and pH, were characterized using RLS. Finally, 2-p-toluidinylnaphthalene-6-sulfonate (TNS) binding, ionic strength and pH control experiments indicate that in the process of EoCen self-assembly, molecular interactions are mediated by both electrostatic and hydrophobic forces, and the hydrophobic interaction has the important status.

  15. Comparison of the marker effects of two different fluorescent dyes in labeling endogenous neural stem cells in the central nervous system

    Directory of Open Access Journals (Sweden)

    Bo-tao TAN

    2012-09-01

    Full Text Available Objective To observe the marker effects of two different fluorescent dyes, DIL and DAPI, in labeling endogenous neural stem cells (ENSCs in rat central nervous system. Methods Thirty-six Sprague-Dawley rats were randomized into staining groups, comprising DIL group and DAPI group, and the corresponding control groups, including DMSO group for DIL group and PBS group for DAPI group. 0.2% DIL 10μl or 10μg/ml DAPI 10μl was stereotactically injected into the lateral ventricle of rats of DIL group or DAPI group, while DMSO or PBS 10μl was introduced into that of DMSO group or PBS group. Neurological severity score (NSS was determined 2 hours and 24 hours respectively after the operation. Rats were sacrificed at day 1, 3, 7 after the injection. Serial coronal sections of the brain and spinal cord were carried out on a cryostat, and then they were observed under a confocal microscope. The fluorescence intensity of the targeted area, which highlighted by labeled ependymal cells, in the brain and spinal cord of cervical vertebrae, thoracic vertebrae and lumbar vertebrae were semi-quantified. Fluorescence intensity of each section was measured in triplicate, and a mean value was obtained. Statistical analysis was performed on 3 data sets, randomly selected from sections of brain and spinal cord obtained at day 1, 3, 7. Results Two hours after DIL injection, the rats showed no evident neurological defect. NSS value was very low, and there was no significant difference compared with the DMSO group (P>0.05. Twenty-four hours later, normal neurological function recovered in all the rats. Red fluorescence could be seen in the cytoplasm of ependymal cells in the lateral ventricle and each spinal cord segment at day 1 after the DIL injection, and it did not disappear until the 7th day. Nuclei of DAPI-labeled lateral ventricle cells were blue, with clear nuclear morphology. Choroid plexus cells of the ventricle were also labeled. However, there was no

  16. Phenotypic modification of human airway epithelial cells in air-liquid interface culture induced by exposure to the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK).

    Science.gov (United States)

    Carson, Johnny L; Brighton, Luisa E; Jaspers, Ilona

    2015-04-01

    The nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent tobacco-specific carcinogen. We used an air-liquid interface epithelial cell culture system to model changes associated with NNK exposure relative to pathologies documented in human tobacco-related illnesses. Although in vitro systems exhibit certain limitations, they often offer accentuation of subtle pathologies. While the distribution of cell types in control cultures typically favors the ciliated cell phenotype, NNK-exposed cultures transitioned to non-ciliated cell phenotypes as well as reflecting features consistent with squamous metaplasia. We conclude that NNK impacts normal growth and differentiation of human airway epithelium in a short interval of time in vitro.

  17. Moss ciliated protozoa as bioindicators. A study on the urban area of Pisa (Italy); Protozoi ciliati del muschio come biondicatori. Uno studio nell'area urbana di Pisa

    Energy Technology Data Exchange (ETDEWEB)

    Verni, F.; Rosati, G. [Pisa Univ., Pisa (Italy). Dipt. di Etologia, Ecologia, Evoluzione

    2000-07-01

    Samples of moss were collected, every month for 7 months, from five zones of Pisa (S2, S3, S4, S5, S6) and a woody zone (S1) as control. For each sample the type and the number of the ciliate species as well as the number of individuals for each species were determined. Lead content was also measured. The data were statistically elaborated and compared. The diversity Shannon index (H) was calculated to determine the health state of ciliate communities. In any case an inverse correlation between H and the lead content was reported; the highest the H value, the lowest the lead content and vice versa. On the basis of the results here reported the use of Ciliates as biondicators appears suitable for the control of urban soil. An analysis like this appears advantageous as it is rather simple and cheap and allows to determine the possible variations in a real time. [Italian] Sono stati analizzati campioni di muschio prelevati, con cadenza mensile per 7 mesi, in 5 stazioni di Pisa (S2, S3, S4, S5, S6) e da una zona boscosa (S1), come controllo. Per ogni campione si e' proceduto all'identificazione dei Ciliati presenti, al conteggio delle specie e del numero di individui per specie, nonche' alla misurazione del piombo presente. I dati sono stati confrontati dopo elaborazione statistica. L'indice della diversita' di Shannon ha fornito informazioni sulla salute della comunita' dei Protozoi delle varie stazioni. In ogni caso risulta una correlazione inversa tra i valori dell'indice di Shannon e la quantita' di piombo: S5, la stazione piu' esposta al traffico, risulta quella piu' degradata. L'uso dei Ciliati come biondicatori risulta quindi appropriato e vantaggioso considerando che e' semplice, poco costoso e permette di valutare in tempi reali variazioni nell'ambiente.

  18. Ultrastructural Observations of the Vitelline Cells of Metamicrocotyla macracantha (Monogenea, Microcotylidae

    Directory of Open Access Journals (Sweden)

    Maria de Fatima D Baptista-Farias

    1998-07-01

    Full Text Available An electron microscopic study of the vitelline follicles of Metamicrocotyla macracantha (Alexander, 1954 Koratha,1955 showed that they are composed of cells in different stages of development. The immature cells have a large nucleus, nucleolus, cytoplasm with free ribosomes and few mitochondria. The developing vitelline cells present granules which are small in the early stages, increasing with maturity. The mature cells have an extensive granular endoplasmic reticulum and droplets of shell-protein; with maturation, clusters of shell protein and yolk bodies are formed and released in the ciliated vitelline ducts. Vitelline development is continuous and all of the cellular stages involved can be found in each follicle.

  19. [Revision of of the subfamily of Metaracoelophryinae de Puytorac 1972 (Oligohymenophora: Hoplytophryida: Hoplytophryidae), astome ciliates of the digestive tract of Oligochaeta worms of Africa: description of five new species].

    Science.gov (United States)

    Fokam, Z; Ngassam, P; Nana, P A; Bricheux, G; Bouchard, P; Sime Ngando, T

    2012-02-01

    Five new species belonging to the astome ciliates, living in the digestive tract of Oligochaeta worms belonging to the genus Alma from Cameroon, have been described. The techniques used are: vital staining, staining of the nucleus with Diamidino Phenyl Indol (DAPI), scanning electron microscopy and silver staining method (Fernandez Galiano, 1976, 1994). This work confirms the presence of the genus Paracoelophrya and Dicoelophrya in the digestive track of the oligochaete Alma from Gabon and Cameroon; it helps to understand the general taxonomy of this Metaracoelophryinae subfamily. Moreover, the homogeneity of this group is confirmed and the phylogenetic relationship inside the Hoplitophryida order need more studies to be solved.

  20. Elements of a neural stem cell niche derived from embryonic stem cells.

    Science.gov (United States)

    Pierret, Chris; Spears, Kathleen; Morrison, Jason A; Maruniak, Joel A; Katz, Martin L; Kirk, Mark D

    2007-12-01

    Recent studies show that adult neural tissues can harbor stem cells within unique niches. In the mammalian central nervous system, neural stem cell (NSC) niches have been identified in the dentate gyrus and the subventricular zone (SVZ). Stem cells in the well-characterized SVZ exist in a microenvironment established by surrounding cells and tissue components, including transit-amplifying cells, neuroblasts, ependymal cells, blood vessels, and a basal lamina. Within this microenvironment, stem cell properties, including proliferation and differentiation, are maintained. Current NSC culture techniques often include the addition of molecular components found within the in vivo niche, such as mitogenic growth factors. Some protocols use bio-scaffolds to mimic the physical growth environment of living tissue. We describe a novel NSC culture system, derived from embryonic stem (ES) cells, that displays elements of an NSC niche in the absence of exogenously applied mitogens or complex physical scaffolding. Mouse ES cells were neuralized with retinoic acid and plated on an entactin-collagen-laminin-coated glass surface at high density (250,000 cells/cm(2)). Six to eight days after plating, complex multicellular structures consisting of heterogeneous cell types developed spontaneously. NSC and progenitor cell proliferation and differentiation continued within these structures. The identity of cellular and molecular components within the cultures was documented using RT-PCR, immunocytochemistry, and neurosphere-forming assays. We show that ES cells can be induced to form structures that exhibit key properties of a developing NSC niche. We believe this system can serve as a useful model for studies of neurogenesis and stem cell maintenance in the NSC niche as well as for applications in stem cell transplantation.

  1. Protocruzia,a highly ambiguous ciliate(Protozoa;Ciliophora):Very likely an ancestral form for Heterotrichea,Colpodea or Spirotrichea? With reevaluation of its evolutionary position based on multigene analyses

    Institute of Scientific and Technical Information of China (English)

    Thorsten; STOECK; Shin; Mann; Kyoon; Al-Rasheid; Khaled; A.; S.; Al-Khedhairy; Abdulaziz; A.

    2010-01-01

    The ciliate genus Protocruzia belongs to one of the most ambiguous taxa considering its systematic position,possibly as a member of the classes Heterotrichea,Spirotrichea or Karyorelictea,which is tentatively placed into Spirotrichea in Lynn’s 2008 system.To test these hypotheses,multigene trees(Bayesian inference,evolutionary distance,maximum parsimony,and maximum likelihood) were constructed using the small subunit rRNA(SSU rRNA) gene,internal transcribed spacer 2(ITS2) and a protein coding gene(histone H4).All analyses agree that:(1) four morphotypes of Protocruzia from different geographical origins group together and form a monophyletic clade,which cannot be assigned to any of the eleven described ciliate classes;(2) it is invariably positioned on an isolated branch separated from the class Spirotrichea suggesting that this clade should be clearly removed from Spirotrichea;(3) this leads us to hypothesize that this taxon may indeed represent a lineage on a class rank.Based on the fact that it is,both morphologically and in molecular features,closely related to the heterotrichs,Colpodea and Oligohymenophorea,Protocruziida might be an ancestral form for the subphylum Intramacronucleata in the evolutionary line from the class Heterotrichea(subphylum Postciliodesmatophora) to higher taxa.

  2. TRPM5-expressing microvillous cells in the main olfactory epithelium

    Directory of Open Access Journals (Sweden)

    Liman Emily R

    2008-11-01

    Full Text Available Abstract Background The main olfactory epithelium (MOE in the nasal cavity detects a variety of air borne molecules that provide information regarding the presence of food, predators and other relevant social and environmental factors. Within the epithelium are ciliated sensory neurons, supporting cells, basal cells and microvillous cells, each of which is distinct in morphology and function. Arguably, the least understood, are the microvillous cells, a population of cells that are small in number and whose function is not known. We previously found that in a mouse strain in which the TRPM5 promoter drives expression of the green fluorescent protein (GFP, a population of ciliated olfactory sensory neurons (OSNs, as well as a population of cells displaying microvilli-like structures is labeled. Here we examined the morphology and immunocytochemical properties of these microvillous-like cells using immunocytochemical methods. Results We show that the GFP-positive microvillous cells were morphologically diversified and scattered throughout the entire MOE. These cells immunoreacted to an antibody against TRPM5, confirming the expression of this ion channel in these cells. In addition, they showed a Ca2+-activated non-selective cation current in electrophysiological recordings. They did not immunoreact to antibodies that label cell markers and elements of the transduction pathways from olfactory sensory neurons and solitary chemosensory cells of the nasal cavity. Further, the TRPM5-expressing cells did not display axon-like processes and were not labeled with a neuronal marker nor did trigeminal peptidergic nerve fibers innervate these cells. Conclusion We provide morphological and immunocytochemical characterization of the TRPM5-expressing microvillous cells in the main olfactory epithelium. Our data demonstrate that these cells are non-neuronal and in terms of chemosensory transduction do not resemble the TRPM5-expressing olfactory sensory neurons

  3. ABUNDANCE AND BIOMASS OF COPEPOD NAUPLII AND CILIATES IN JIAOZHOU BAY%胶州湾桡足类幼虫和浮游生纤毛虫的丰度与生物量

    Institute of Scientific and Technical Information of China (English)

    张武昌; 王荣

    2001-01-01

    This paper presents data of ciliates and copepod nauplii abundance and biomass from eight cruises (September, December, 1997; February, April, August, November, 1998; February, May, 1999) in Jiaozhou Bay. Water samples were taken by 2L Niskin Bottles at ten stations during every cruise. One liter water was preserved in plastic bottle with Lugol's (1%). The sample scheme of water layer was surface, middle and bottom according to water depth. The samples were examined with the method of Utermohl (1958) one month after sampling. Carbon:volumn ratio was 0.05 pgC/μm3 for copepod nauplii (Mullin, 1969), 0.19pgC/μm3 for ciliates (Putt et al, 1989). Body volume of tintinnids was assumed to be 50% of that of the lorica (Beers et al, 1969).   Copepod nauplii dominated in September 1997. The aloricate oligotrichous ciliates were dominant through December 1997 to February 1999. Tintinnids dominated in May 1999. The maximum abundance of copepod nauplii, aloricate ciliates and tintinnids were 850 (August, 1998), 21300 (August, 1998) and 1720 ind/L (May, 1999) respectively. The total abundance of the above three in the surface layer was 10—22350 ind/L, with larger abundance in the inner part of the bay. There was no obvious trend in the vertical distribution. The total biomass of copepod nauplii, aloricate ciliates and tintinnids in the surface layer was in the range of 0.10—380.27μgC/L, water column biomass 0.20—1426.02mgC/m2.%1997年9月、12月,1998年2月、4月、8月、11月以及1999年2月和5月在胶州湾采集桡足类幼虫和浮游生纤毛虫的样品。样品用Lugol's试剂固定(最后浓度1%),用显微镜计数桡足类幼虫和浮游生纤毛虫的丰度,并计算总生物量(表层生物量和水体生物量)。桡足类幼虫、无壳纤毛虫和砂壳纤毛虫的最大丰度分别为850ind/L(1998年8月)、21300ind/L(1998年8月)和1720ind/L(1999年5月)。表层的总丰度为10—22630ind/L,水平分布湾内比湾外多。表层纤

  4. Zebrafish models of idiopathic scoliosis link cerebrospinal fluid flow defects to spine curvature.

    Science.gov (United States)

    Grimes, D T; Boswell, C W; Morante, N F C; Henkelman, R M; Burdine, R D; Ciruna, B

    2016-06-10

    Idiopathic scoliosis (IS) affects 3% of children worldwide, yet the mechanisms underlying this spinal deformity remain unknown. Here we show that ptk7 mutant zebrafish, a faithful developmental model of IS, exhibit defects in ependymal cell cilia development and cerebrospinal fluid (CSF) flow. Transgenic reintroduction of Ptk7 in motile ciliated lineages prevents scoliosis in ptk7 mutants, and mutation of multiple independent cilia motility genes yields IS phenotypes. We define a finite developmental window for motile cilia in zebrafish spine morphogenesis. Notably, restoration of cilia motility after the onset of scoliosis blocks spinal curve progression. Together, our results indicate a critical role for cilia-driven CSF flow in spine development, implicate irregularities in CSF flow as an underlying biological cause of IS, and suggest that noninvasive therapeutic intervention may prevent severe scoliosis.

  5. Planar cell polarity signaling in vertebrates.

    Science.gov (United States)

    Jones, Chonnettia; Chen, Ping

    2007-02-01

    Planar cell polarity (PCP) refers to the polarization of a field of cells within the plane of a cell sheet. This form of polarization is required for diverse cellular processes in vertebrates, including convergent extension (CE), the establishment of PCP in epithelial tissues and ciliogenesis. Perhaps the most distinct example of vertebrate PCP is the uniform orientation of stereociliary bundles at the apices of sensory hair cells in the mammalian auditory sensory organ. The establishment of PCP in the mammalian cochlea occurs concurrently with CE in this ciliated epithelium, therefore linking three cellular processes regulated by the vertebrate PCP pathway in the same tissue and emerging as a model system for dissecting PCP signaling. This review summarizes the morphogenesis of this model system to assist the interpretation of the emerging data and proposes molecular mechanisms underlying PCP signaling in vertebrates.

  6. The neural elements in the lining of the ventricular-subventricular zone: making an old story new by high-resolution scanning electron microscopy.

    Science.gov (United States)

    Haemmerle, Carlos Alexandre Dos Santos; Nogueira, Maria Inês; Watanabe, Ii-Sei

    2015-01-01

    The classical description of the neural elements that compose the lining of brain ventricles introduces us to the single layer of ependymal cells. However, new findings, especially in the lateral ventricle (LV)-the major niche for the generation of new neurons in the adult brain-have provided information about additional cell elements that influence the organization of this part of the ventricular system and produce important contributions to neurogenesis. To complement the cell neurochemistry findings, we present a three-dimensional in situ description that demonstrates the anatomical details of the different types of ciliated cells and the innervation of these elements. After processing adult rat brains for ultrastructural analysis by high-resolution scanning electron microscopy (HRSEM) and transmission electron microscopy, we observed a heterogeneous pattern of cilia distribution at the different poles of the LV surface. Furthermore, we describe the particular three-dimensional aspects of the ciliated cells of the LV, in addition the fiber bundles and varicose axons surrounding these cells. Therefore, we provide a unique ultrastructural description of the three-dimensional in situ organization of the LV surface, highlighting its innervation, to corroborate the available neurochemical and functional findings regarding the factors that regulate this neurogenic niche.

  7. The neural elements in the lining of the ventricular-subventricular zone: making an old story new by high-resolution scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Dos Santos Haemmerle

    2015-10-01

    Full Text Available The classical description of the neural elements that compose the lining of brain ventricles introduces us to the single layer of ependymal cells. However, new findings, especially in the lateral ventricle - the major niche for the generation of new neurons in the adult brain - have provided information about additional cell elements that influence the organization of this part of the ventricular system and produce important contributions to neurogenesis. To complement the cell neurochemistry findings, we present a three-dimensional in situ description that demonstrates the anatomical details of the different types of ciliated cells and the innervation of these elements. After processing adult rat brains for ultrastructural analysis by high-resolution scanning electron microscopy and transmission electron microscopy, we observed a heterogeneous pattern of cilia distribution at the different poles of the lateral ventricle surface. Furthermore, we describe the particular three-dimensional aspects of the ciliated cells of the lateral ventricle, in addition the fiber bundles and varicose axons surrounding these cells. Therefore, we provide a unique ultrastructural description of the three-dimensional in situ organization of the lateral ventricle surface, highlighting its innervation, to corroborate the available neurochemical and functional findings regarding the factors that regulate this neurogenic niche.

  8. Cell multiplication following partial enzymatic removal of surface coat.

    Science.gov (United States)

    Wyroba, E

    1978-08-01

    Treatment of Paramecium aurelia with trypsin or pronase (1 mg per 10(5) cells, at 0 to 4 degrees C) partially removes the surface coat and modifies significantly multiplication of cells. The division rate after 24 hours of cultivation is diminished approximately twice in the case of pronase-treated cells and 1.5 for tyrpsin-digested ciliates as compared with the control. On the second day the division rate increases rapidly and number of cell divisions exceeds the values observed in the control. After 72 hours of cultivation the division rate in both untreated and enzyme-treated cells is almost the same. It is concluded that the observed inhibition of cell fission results from the enzymatic removal of the surface coat--the integrity of this surface coat seems to be necessary in the process of cell division. The influence of environmental factors on the rate of growth is presented.

  9. Study on development and localization of CTGF-immunoreactive cells in central nervous system of rats

    Institute of Scientific and Technical Information of China (English)

    SU Bing-yin; CAI Wen-qin; ZHANNG Cheng-gang; B.Perbal

    2001-01-01

    Objective: To study the development of connective tissue growth factor(CTGF) immunoreactive cells in the central nervous system (CNS) of E8-P300 rats. Methods: Immunocytochemistry was employed in our study. Results: No CTGF-immunoreactive cells were detected in the CNS of rats during prenatal stages. A few of CTGF-positive cells were detected in the early postnatal stage. However, the positive cells increased gradually in later stages. CTGF-immunoreactive cells widely distributed in the CNS of rats in the first 30 to 60 days postnatally, and the density of immunoreactive products was the highest in these days. The number and staining intensity of CTGF-positive cells decreased and their area of distribution diminished gradually with age. The positive cells included neurons mainly located in the cingulate cortex,striatum, hippocampus, hypothalamus and cerebellum, and astrocytes in white matter of the spinal cord and ependymal cells of the brain. Most of CTGF-immunoreactive cells were quite big in size with a long process. Conclusion: CTGF-immunoreactive cells were found in the CNS of rats, and their numbers and positive signal decreased with the age.

  10. Cell chirality: its origin and roles in left-right asymmetric development.

    Science.gov (United States)

    Inaki, Mikiko; Liu, Jingyang; Matsuno, Kenji

    2016-12-19

    An item is chiral if it cannot be superimposed on its mirror image. Most biological molecules are chiral. The homochirality of amino acids ensures that proteins are chiral, which is essential for their functions. Chirality also occurs at the whole-cell level, which was first studied mostly in ciliates, single-celled protozoans. Ciliates show chirality in their cortical structures, which is not determined by genetics, but by 'cortical inheritance'. These studies suggested that molecular chirality directs whole-cell chirality. Intriguingly, chirality in cellular structures and functions is also found in metazoans. In Drosophila, intrinsic cell chirality is observed in various left-right (LR) asymmetric tissues, and appears to be responsible for their LR asymmetric morphogenesis. In other invertebrates, such as snails and Caenorhabditis elegans, blastomere chirality is responsible for subsequent LR asymmetric development. Various cultured cells of vertebrates also show intrinsic chirality in their cellular behaviours and intracellular structural dynamics. Thus, cell chirality may be a general property of eukaryotic cells. In Drosophila, cell chirality drives the LR asymmetric development of individual organs, without establishing the LR axis of the whole embryo. Considering that organ-intrinsic LR asymmetry is also reported in vertebrates, this mechanism may contribute to LR asymmetric development across phyla.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.

  11. Cell chirality: its origin and roles in left–right asymmetric development

    Science.gov (United States)

    Inaki, Mikiko; Liu, Jingyang

    2016-01-01

    An item is chiral if it cannot be superimposed on its mirror image. Most biological molecules are chiral. The homochirality of amino acids ensures that proteins are chiral, which is essential for their functions. Chirality also occurs at the whole-cell level, which was first studied mostly in ciliates, single-celled protozoans. Ciliates show chirality in their cortical structures, which is not determined by genetics, but by ‘cortical inheritance’. These studies suggested that molecular chirality directs whole-cell chirality. Intriguingly, chirality in cellular structures and functions is also found in metazoans. In Drosophila, intrinsic cell chirality is observed in various left–right (LR) asymmetric tissues, and appears to be responsible for their LR asymmetric morphogenesis. In other invertebrates, such as snails and Caenorhabditis elegans, blastomere chirality is responsible for subsequent LR asymmetric development. Various cultured cells of vertebrates also show intrinsic chirality in their cellular behaviours and intracellular structural dynamics. Thus, cell chirality may be a general property of eukaryotic cells. In Drosophila, cell chirality drives the LR asymmetric development of individual organs, without establishing the LR axis of the whole embryo. Considering that organ-intrinsic LR asymmetry is also reported in vertebrates, this mechanism may contribute to LR asymmetric development across phyla. This article is part of the themed issue ‘Provocative questions in left–right asymmetry’. PMID:27821533

  12. Characterization of neural stem cells and their progeny in the sensory circumventricular organs of adult mouse.

    Science.gov (United States)

    Furube, Eriko; Morita, Mitsuhiro; Miyata, Seiji

    2015-11-01

    Although evidence has accumulated that neurogenesis and gliogenesis occur in the subventricular zone (SVZ) and subgranular zone (SGZ) of adult mammalian brains, recent studies indicate the presence of neural stem cells (NSCs) in adult brains, particularly the circumventricular regions. In the present study, we aimed to determine characterization of NSCs and their progenitor cells in the sensory circumventricular organs (CVOs), including organum vasculosum of the lamina terminalis, subfornical organ, and area postrema of adult mouse. There were two types of NSCs: tanycyte-like ependymal cells and astrocyte-like cells. Astrocyte-like NSCs proliferated slowly and oligodendrocyte progenitor cells (OPCs) and neural progenitor cells (NPCs) actively divided. Molecular marker protein expression of NSCs and their progenitor cells were similar to those reported in the SVZ and SGZ, except that astrocyte-like NSCs expressed S100β. These circumventricular NSCs possessed the capacity to give rise to oligodendrocytes and sparse numbers of neurons and astrocytes in the sensory CVOs and adjacent brain regions. The inhibition of vascular endothelial growth factor (VEGF) signaling by using a VEGF receptor-associated tyrosine kinase inhibitor AZD2171 largely suppressed basal proliferation of OPCs. A single systemic administration of lipopolysaccharide attenuated proliferation of OPCs and induced remarkable proliferation of microglia. The present study indicates that sensory circumventricular NSCs provide new neurons and glial cells in the sensory CVOs and adjacent brain regions.

  13. Observing planar cell polarity in multiciliated mouse airway epithelial cells.

    Science.gov (United States)

    Vladar, Eszter K; Lee, Yin Loon; Stearns, Tim; Axelrod, Jeffrey D

    2015-01-01

    The concerted movement of cilia propels inhaled contaminants out of the lungs, safeguarding the respiratory system from toxins, pathogens, pollutants, and allergens. Motile cilia on the multiciliated cells (MCCs) of the airway epithelium are physically oriented along the tissue axis for directional motility, which depends on the planar cell polarity (PCP) signaling pathway. The MCCs of the mouse respiratory epithelium have emerged as an important model for the study of motile ciliogenesis and the PCP signaling mechanism. Unlike other motile ciliated or planar polarized tissues, airway epithelial cells are relatively easily accessible and primary cultures faithfully model many of the essential features of the in vivo tissue. There is growing interest in understanding how cells acquire and polarize motile cilia due to the impact of mucociliary clearance on respiratory health. Here, we present methods for observing and quantifying the planar polarized orientation of motile cilia both in vivo and in primary culture airway epithelial cells. We describe how to acquire and evaluate electron and light microscopy images of ciliary ultrastructural features that reveal planar polarized orientation. Furthermore, we describe the immunofluorescence localization of PCP pathway components as a simple readout for airway epithelial planar polarization and ciliary orientation. These methods can be adapted to observe ciliary orientation in other multi- and monociliated cells and to detect PCP pathway activity in any tissue or cell type.

  14. Effects of protein kinase C activators and staurosporine on protein kinase activity, cell survival, and proliferation in Tetrahymena thermophila

    DEFF Research Database (Denmark)

    Straarup, EM; Schousboe, P; Hansen, HQ;

    1997-01-01

    with either PMA or OAG, or at 2,500 cells ml-1. At 500 cells ml-1 PMA induced the in vivo phosphorylation of at least six proteins. The myelin basic protein fragment 4-14 was phosphorylated in vitro in crude extracts of a culture of 250,000 cells ml-1. Both the in vivo and the in vitro phosphorylation were......Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein...... kinase C activators phorbol 12-myristate 13-acetate (PMA) or 1-oleyl 2-acetate glycerol (OAG) when added to 250 cells ml-1 supported cell survival and proliferation. In the presence of the serine and threonine kinase inhibitor staurosporine the cells died both at 250 cells ml-1 in cultures supplemented...

  15. Internalization of cycloheptaamylose-dansyl chloride complex during labelling of surface membrane in living Paramecium aurelia cells.

    Science.gov (United States)

    Giordano, P A; Wyroba, E; Bottiroli, G

    1985-01-01

    Internalization of cycloheptaamylose-dansyl chloride complex during surface labelling of living long-term starved Paramecium aurelia cells has been observed. This process may be inhibited by pretreatment of the ciliates with dichloroisoproterenol. Uptake of cycloheptaamylose-dansyl chloride may be visualized only after UV preirradiation: the appearance of orange-fluorescing vacuoles of diameter 2.3-4.5 micron may then be observed. Microspectrographic analysis performed on the cells and dansyl derivatives indicates that this fluorescence is produced by a photochemical reaction of dansyl chloride - released from CDC complex inside the digestive vacuoles-under the influence of UV irradiation.

  16. Sperm storage and spermatozoa interaction with epithelial cells in oviduct of Chinese soft-shelled turtle, Pelodiscus sinensis.

    Science.gov (United States)

    Chen, Shaofan; Zhang, Linli; Le, Yuan; Waqas, Yasir; Chen, Wei; Zhang, Qian; Ullah, Shakeeb; Liu, Tengfei; Hu, Lisi; Li, Quanfu; Yang, Ping

    2015-08-01

    Spermatozoa are known to be stored within the female genital tract after mating in various species to optimize timing of reproductive events such as copulation, fertilization, and ovulation. The mechanism supporting long-term sperm storage is still unclear in turtles. The aim of this study was to investigate the interaction between the spermatozoa and oviduct in Chinese soft-shelled turtle by light and electron microscopy to reveal the potential cytological mechanism of long-term sperm storage. Spermatozoa were stored in isthmus, uterine, and vagina of the oviduct throughout the year, indicating long-term sperm storage in vivo. Sperm heads were always embedded among the cilia and even intercalated into the apical hollowness of the ciliated cells in the oviduct mucosal epithelium. The stored spermatozoa could also gather in the gland conduit. There was no lysosome distribution around the hollowness of the ciliated cell, suggesting that the ciliated cells of the oviduct can support the spermatozoa instead of phagocytosing them in the oviduct. Immune cells were sparse in the epithelium and lamina propria of oviduct, although few were found inside the blood vessel of mucosa, which may be an indication of immune tolerance during sperm storage in the oviduct of the soft-shelled turtle. These characteristics developed in the turtle benefited spermatozoa survival for a long time as extraneous cells in the oviduct of this species. These findings would help to improve the understanding of reproductive regularity and develop strategies of species conservation in the turtle. The Chinese soft-shelled turtle may be a potential model for uncovering the mechanism behind the sperm storage phenomenon.

  17. The nuclear pore complex acts as a master switch for nuclear and cell differentiation

    Science.gov (United States)

    Iwamoto, Masaaki; Hiraoka, Yasushi; Haraguchi, Tokuko

    2015-01-01

    Cell differentiation is associated with the functional differentiation of the nucleus, in which alteration of the expression profiles of transcription factors occurs to destine cell fate. Nuclear transport machineries, such as importin-α, have also been reported as critical factors that induce cell differentiation. Using various fluorescence live cell imaging methods, including time-lapse imaging, FRAP analysis and live-cell imaging associated correlative light and electron microscopy (Live CLEM) of Tetrahymena, a unicellular ciliated protozoan, we have recently discovered that type switching of the NPC is the earliest detectable event of nuclear differentiation. Our studies suggest that this type switching of the NPC directs the fate of the nucleus to differentiate into either a macronucleus or a micronucleus. Our findings in this organism may provide new insights into the role of the NPC in controlling nuclear functions in general in eukaryotes, including controlling cell fate leading to cell differentiation in multicellular metazoa. PMID:26479399

  18. Heterogeneous vesicles in mucous epithelial cells of posterior esophagus of Chinese giant salamander (Andrias davidianus

    Directory of Open Access Journals (Sweden)

    H. Zhang

    2015-08-01

    Full Text Available The Chinese giant salamander belongs to an old lineage of salamanders and endangered species. Many studies of breeding and disease regarding this amphibian had been implemented. However, the studies on the ultrastructure of this amphibian are rare. In this work, we provide a histological and ultrastructural investigation on posterior esophagus of Chinese giant salamander. The sections of amphibian esophagus were stained by hematoxylin & eosin (H&E. Moreover, the esophageal epithelium was observed by transmission electron microscopy (TEM. The results showed that esophageal epithelium was a single layer epithelium, which consisted of mucous cells and columnar cells. The esophageal glands were present in submucosa. The columnar cells were ciliated. According to the diverging ultrastructure of mucous vesicles, three types of mucous cells could be identified in the esophageal mucosa: i electron-lucent vesicles mucous cell (ELV-MC; ii electron-dense vesicles mucous cell (EDV-MC; and iii mixed vesicles mucous cell (MV-MC.

  19. GENETIC RELATIONSHIPS OF FIVE PERITRICHOUS CILIATES INFERRED FROM INTER SIMPLE SEQUENCE REPEAT (ISSR) MOLECULAR MARKERS%五种缘毛类纤毛虫遗传关系的ISSR研究

    Institute of Scientific and Technical Information of China (English)

    张文静; 余育和; 沈韫芬

    2005-01-01

    In this study, ISSR (inter simple sequence repeat) molecular markers were used to clarify genetic relationships of five peritrichous ciliates: Carchesium polypinum, Epistylis chrysemydis, E. plicatilis, E. urceolata and Vorticella campanula.From 34 primers, 13 polymorphic primers were selected and tested. The genetic distance values going from 0.6667 to 1. 0000 among the five species show the ISSR-PCR method has a high resolution. In the phylogenetic tree constructed with the unweighted pair group method using arithmetic averages (UPGMA), V. campanula was separated from other species firstly; C.polypinum and E. chrysemydis were closely related; in the group of Epistylis species, E. plicatilis and E. urceolata were first clustered together and then grouped with E. chrysemydis. These results were compared with the phylogenetic tree from the complete small subunit ribosomal RNA (SSrRNA) gene sequences. We found that: 1) ISSR primers can give the informative profiles in peritrichous ciliates; 2) C. polypinum has a nearer relation with Epistylis than V. campanula. The colonial or solitary status might be a more important phylogenetic character within peritrichs than the characters of stalk and the myoneme; 3) E.urceolata shared closer relationship with E. plicatilis than E. chrysemydis. The hollow nature of the stalk is a useful phylogenetic and taxonomic character in the genus Epistylis. This study demonstrated that ISSR-PCR method was a new useful method to reveal the relationships among related or similar species in ciliates.%应用ISSR分子标记揭示了5种缘毛类纤毛虫(Carchesium polypinum,Epistylis chrysemydis,E.plicatilis,E.urceolata和Vorticella campanula)的遗传关系.从34个引物中筛选到13个多态性高的引物进行研究.得到的遗传距离(0.666 7~1.000 0)显示ISSR技术具有较高的分辨率.依据构建的UPGMA聚类树,V.campanula首先和其他种类分开;C.polypinum和E.chrysemydis聚在了一起;在3种Epistylis纤毛虫中,E

  20. Predação e canibalismo entre protozoários ciliados (Ciliophora: Entodiniomorphida: Ophryoscolecidae no rúmen de ovinos (Ovis aries Predation and cannibalism among ciliate protozoans (Ciliophora: Entodiniomorphida: Ophryoscolecidae in the rumen of sheep (Ovis aries

    Directory of Open Access Journals (Sweden)

    Isabel Martinele

    2008-09-01

    Full Text Available O objetivo deste trabalho foi registrar ocorrências de predação e canibalismo em protozoários ciliados no rúmen de ovinos. Foram analisadas amostras de conteúdo ruminal de cinco ovinos mestiços Santa Inês, fistulados no rúmen, mantidos em pastagem natural de caatinga, no município de Sertânia, Pernambuco. Foram obtidas seis amostras de conteúdo ruminal de cada ovino, totalizando 30 amostras, as quais foram fixadas em formalina 18,5% (v/v. De cada amostra foi retirada uma alíquota de 1 ml de conteúdo ruminal ao qual se adicionaram três gotas de solução de lugol para a coloração e identificação dos protozoários ciliados. Estas alíquotas foram analisadas utilizando-se lâminas e lamínulas, em campos determinados randomicamente. Constatou-se a ocorrência de interações do tipo predador-presa entre ciliados de Ophryoscolecidae Stein, 1859, onde Elytroplastron bubali (Dogiel, 1928 apresentou comportamento predatório sobre Enoploplastron triloricatum (Dogiel, 1925 e sobre outras espécies de Epidinium Crawley, 1923 e de Entodinium Stein, 1859. Foram ainda observados casos de canibalismo entre espécimes de E. bubali, o que consiste no primeiro registro deste tipo de interação nesta espécie. Registra-se, ainda, pela primeira vez a ocorrência de E. bubali no rúmen de ovinos no Brasil.The objective of the present study was to record the occurrence of predation and cannibalism among ciliate protozoans in the rumen of sheep. The analyzed samples consisted of ruminal contents of five fistulated Santa Inez crossbred sheep, maintained in a natural caatinga (scrubland pasture in the municipality of Sertânia, Pernambuco. Six samples of ruminal content were obtained from each sheep (total of 30 samples and fixed in formalin at 18.5% (v/v. One 1 ml aliquot was obtained from each sample of ruminal content and received tree drops of a lugol solution for staining and identification of protozoa ciliates. These aliquots were analyzed in

  1. Aquaporin-4 in Astroglial Cells in the CNS and Supporting Cells of Sensory Organs—A Comparative Perspective

    Directory of Open Access Journals (Sweden)

    Corinna Gleiser

    2016-08-01

    Full Text Available The main water channel of the brain, aquaporin-4 (AQP4, is one of the classical water-specific aquaporins. It is expressed in many epithelial tissues in the basolateral membrane domain. It is present in the membranes of supporting cells in most sensory organs in a specifically adapted pattern: in the supporting cells of the olfactory mucosa, AQP4 occurs along the basolateral aspects, in mammalian retinal Müller cells it is highly polarized. In the cochlear epithelium of the inner ear, it is expressed basolaterally in some cells but strictly basally in others. Within the central nervous system, aquaporin-4 (AQP4 is expressed by cells of the astroglial family, more specifically, by astrocytes and ependymal cells. In the mammalian brain, AQP4 is located in high density in the membranes of astrocytic endfeet facing the pial surface and surrounding blood vessels. At these locations, AQP4 plays a role in the maintenance of ionic homeostasis and volume regulation. This highly polarized expression has not been observed in the brain of fish where astroglial cells have long processes and occur mostly as radial glial cells. In the brain of the zebrafish, AQP4 immunoreactivity is found along the radial extent of astroglial cells. This suggests that the polarized expression of AQP4 was not present at all stages of evolution. Thus, a polarized expression of AQP4 as part of a control mechanism for a stable ionic environment and water balanced occurred at several locations in supporting and glial cells during evolution. This initially basolateral membrane localization of AQP4 is shifted to highly polarized expression in astrocytic endfeet in the mammalian brain and serves as a part of the neurovascular unit to efficiently maintain homeostasis.

  2. Aquaporin-4 in Astroglial Cells in the CNS and Supporting Cells of Sensory Organs-A Comparative Perspective.

    Science.gov (United States)

    Gleiser, Corinna; Wagner, Andreas; Fallier-Becker, Petra; Wolburg, Hartwig; Hirt, Bernhard; Mack, Andreas F

    2016-08-26

    The main water channel of the brain, aquaporin-4 (AQP4), is one of the classical water-specific aquaporins. It is expressed in many epithelial tissues in the basolateral membrane domain. It is present in the membranes of supporting cells in most sensory organs in a specifically adapted pattern: in the supporting cells of the olfactory mucosa, AQP4 occurs along the basolateral aspects, in mammalian retinal Müller cells it is highly polarized. In the cochlear epithelium of the inner ear, it is expressed basolaterally in some cells but strictly basally in others. Within the central nervous system, aquaporin-4 (AQP4) is expressed by cells of the astroglial family, more specifically, by astrocytes and ependymal cells. In the mammalian brain, AQP4 is located in high density in the membranes of astrocytic endfeet facing the pial surface and surrounding blood vessels. At these locations, AQP4 plays a role in the maintenance of ionic homeostasis and volume regulation. This highly polarized expression has not been observed in the brain of fish where astroglial cells have long processes and occur mostly as radial glial cells. In the brain of the zebrafish, AQP4 immunoreactivity is found along the radial extent of astroglial cells. This suggests that the polarized expression of AQP4 was not present at all stages of evolution. Thus, a polarized expression of AQP4 as part of a control mechanism for a stable ionic environment and water balanced occurred at several locations in supporting and glial cells during evolution. This initially basolateral membrane localization of AQP4 is shifted to highly polarized expression in astrocytic endfeet in the mammalian brain and serves as a part of the neurovascular unit to efficiently maintain homeostasis.

  3. Morphological Studies of a Ciliate from the External Ulcerative Japanese Flounder, Paralichthys Olivaceus%一种纤毛虫的分类及形态研究 ——寄生于牙鲆体表溃烂组织中的指状拟舟虫

    Institute of Scientific and Technical Information of China (English)

    周丽; 徐奎栋; 战文斌; 宋微波

    2001-01-01

    报道从牙鲆(Paralichthysolivaceus)体表溃烂组织分离的一种纤毛虫,通过活体观察、扫描电镜、蛋白银染色法、银浸法,对其形态学及纤毛图式做了研究。经鉴定,该纤毛虫为指状拟舟虫(Paralembus digitiformis Kahl,1933),隶属于寡膜纲、盾纤目、嗜污科、拟舟虫属。这是指状拟舟虫在牙鲆上兼性寄生的首次报道。%An external ulcerative disease frequently occurred in Ja paneseflounder, Paralichthys olivaceus, cultured in artificial propagation facilities along the coasts of Shandong, China, has caused mass mortalities in r ecent years. The ciliate was a pathogen to flounder and was identified as Para lembus digitiformis Kahl 1933, a marine facultative parasitic scuticociliatid ciliate. Morphological studies were made on living observations and specimens tr eated with protargol-impregnation techniques and Chatton-Lwoff silver impregna tion techniques as well as scanning electron microscopy. The ciliate, Paralemb us digitiformis Kahl 1933, as an opportunistic pathogen of cultured flounder, is first reported in this paper.

  4. GRHL2 coordinates regeneration of a polarized mucociliary epithelium from basal stem cells.

    Science.gov (United States)

    Gao, Xia; Bali, Aman S; Randell, Scott H; Hogan, Brigid L M

    2015-11-09

    Pseudostratified airway epithelium of the lung is composed of polarized ciliated and secretory cells maintained by basal stem/progenitor cells. An important question is how lineage choice and differentiation are coordinated with apical-basal polarity and epithelial morphogenesis. Our previous studies indicated a key integrative role for the transcription factor Grainyhead-like 2 (Grhl2). In this study, we present further evidence for this model using conditional gene deletion during the regeneration of airway epithelium and clonal organoid culture. We also use CRISPR/Cas9 genome editing in primary human basal cells differentiating into organoids and mucociliary epithelium in vitro. Loss of Grhl2 inhibits organoid morphogenesis and the differentiation of ciliated cells and reduces the expression of both notch and ciliogenesis genes (Mcidas, Rfx2, and Myb) with distinct Grhl2 regulatory sites. The genome editing of other putative target genes reveals roles for zinc finger transcription factor Znf750 and small membrane adhesion glycoprotein in promoting ciliogenesis and barrier function as part of a network of genes coordinately regulated by Grhl2.

  5. The role of Scgb1a1+ Clara cells in the long-term maintenance and repair of lung airway, but not alveolar, epithelium.

    Science.gov (United States)

    Rawlins, Emma L; Okubo, Tadashi; Xue, Yan; Brass, David M; Auten, Richard L; Hasegawa, Hiroshi; Wang, Fan; Hogan, Brigid L M

    2009-06-05

    To directly test the contribution of Scgb1a1(+) Clara cells to postnatal growth, homeostasis, and repair of lung epithelium, we generated a Scgb1a1-CreER "knockin" mouse for lineage-tracing these cells. Under all conditions tested, the majority of Clara cells in the bronchioles both self-renews and generates ciliated cells. In the trachea, Clara cells give rise to ciliated cells but do not self-renew extensively. Nevertheless, they can contribute to tracheal repair. In the postnatal mouse lung, it has been proposed that bronchioalveolar stem cells (BASCs) which coexpress Scgb1a1 (Secretoglobin1a1) and SftpC (Surfactant Protein C), contribute descendants to both bronchioles and alveoli. The putative BASCs were lineage labeled in our studies. However, we find no evidence for the function of a special BASC population during postnatal growth, adult homeostasis, or repair. Rather, our results support a model in which the trachea, bronchioles, and alveoli are maintained by distinct populations of epithelial progenitor cells.

  6. Acellular Lung Scaffolds Direct Differentiation of Endoderm to Functional Airway Epithelial Cells: Requirement of Matrix-Bound HS Proteoglycans

    Directory of Open Access Journals (Sweden)

    Sharareh Shojaie

    2015-03-01

    Full Text Available Efficient differentiation of pluripotent cells to proximal and distal lung epithelial cell populations remains a challenging task. The 3D extracellular matrix (ECM scaffold is a key component that regulates the interaction of secreted factors with cells during development by often binding to and limiting their diffusion within local gradients. Here we examined the role of the lung ECM in differentiation of pluripotent cells in vitro and demonstrate the robust inductive capacity of the native lung matrix alone. Extended culture of stem cell-derived definitive endoderm on decellularized lung scaffolds in defined, serum-free medium resulted in differentiation into mature airway epithelia, complete with ciliated cells, club cells, and basal cells with morphological and functional similarities to native airways. Heparitinase I, but not chondroitinase ABC, treatment of scaffolds revealed that the differentiation achieved is dependent on heparan sulfate proteoglycans and its bound factors remaining on decellularized scaffolds.

  7. 显示纤毛虫细胞微管骨架的两种荧光标记方法%Two fluorescent labeling methods for revealing microtubular cytoskeleton in ciliates

    Institute of Scientific and Technical Information of China (English)

    余齐耀; 张萌; 陈季武; 倪兵

    2012-01-01

    应用直接荧光标记和免疫荧光标记显微术显示了几种原生动物纤毛虫(如尾草履虫、大尾柱虫、阔口游仆虫)的细胞微管骨架,并据结果提出了用所述方法制备标本时需注意的几个方面:对游仆虫,可以忽略某些步骤;对大尾柱虫各种药品的浓度以及处理时间以较小为宜.%The direct fluorescent labeling and the immunofluorescent labeling with antibody against a-tubulin were used to show the mi-crotubular cytoskeleton of several ciliate protozoans such as Paramecium caudatum, Euplotes eurystomus and Urostyla grandis. Based on the results, the study also proposed some points which should be noted in the preparation of specimen with the methods mentioned a-bove (I.e. , some steps can be ignored in Euplotes; a lower concentration of various drugs and a less processing time will be appropriate for Urostyla species).

  8. Classification of the peritrich ciliate Opisthonecta matiensis (Martín-Cereceda et al. 1999) as Telotrochidium matiense nov. comb., based on new observations and SSU rDNA phylogeny.

    Science.gov (United States)

    Martín-Cereceda, Mercedes; Guinea, Almudena; Bonaccorso, Elisa; Dyal, Patricia; Novarino, Gianfranco; Foissner, Wilhelm

    2007-11-01

    New observations on Opisthonecta matiensis Martín-Cereceda et al. [1999. Description of Opisthonecta matiensis n. sp. (Protozoa, Ciliophora), a new peritrich ciliate from wastewater. J. Eukaryot. Microbiol. 46, 283-289] especially the lack of an epistomial membrane, reveal that the species does not belong to the genus Opisthonecta, but to Telotrochidium, the other genus within the family Opisthonectidae Foissner, 1975. The contractile vacuole and the cytopyge are on the dorsal wall of the vestibulum and the trochal band is limited distally and proximally by rows of narrowly spaced pellicular pores. Thus the species is redefined as Telotrochidium matiense nov. comb. The morphological, cortical and nuclear events occurring during conjugation are illustrated, compared with those in other species, and phylogenetically discussed. Invariably, the microconjugants attach to and penetrate the lateral side of the macroconjugants. Nuclear processes are very similar to those reported from other peritrichs. The small subunit rRNA gene (SSU rDNA) is sequenced and the phylogeny within Opisthonectidae and peritrichs examined. T. matiense is more closely related to Epistylis (63% Maximum Parsimony (MP), 85% Maximum Likelihood (ML)) than to any other genus, while another representative of the family, viz., Opisthonecta henneguyi, is closely related to Vorticella microstoma, Astylozoon enriquesi and clone RT3n18 (100% MP, 100% ML). Morphology and gene sequences suggest that Telotrochidium and Opisthonecta have derived from different lineages of stalked peritrichs: Opisthonecta could have arisen from peritrichs with stalk myonemes, while Telotrochidium probably evolved from peritrichs without stalk myonemes.

  9. Cells

    Directory of Open Access Journals (Sweden)

    Zhao-Hui Jin

    2012-11-01

    Full Text Available As cancer stem cells (CSCs are postulated to play critical roles in cancer development, including metastasis and recurrence, CSC imaging would provide valuable information for cancer treatment and lead to CSC-targeted therapy. To assess the possibility of in vivo CSC targeting, we conducted basic studies on radioimmunotargeting of cancer cells positive for CD133, a CSC marker recognized in various cancers. Antibodies against CD133 were labeled with 125I, and their in vitro cell binding properties were tested. Using the same isotype IgG as a control, in vivo biodistribution of the labeled antibody retaining immunoreactivity was examined in mice bearing an HCT116 xenograft in which a population of the cancer cells expressed CD133. Intratumoral distribution of the labeled antibody was examined and compared to the CD133 expression pattern. The 125I-labeled anti-CD133 antibody showed a modest but significantly higher accumulation in the HCT116 xenograft compared to the control IgG. The intratumoral distribution of the labeled antibody mostly overlapped with the CD133 expression, whereas the control IgG was found in the area close to the necrotic tumor center. Our results indicate that noninvasive in vivo targeting of CSCs could be possible with radiolabeled antibodies against cell membrane markers.

  10. Overexpression of nestin and vimentin in the ependyma of spinal cords from hydrocephalic infants.

    Science.gov (United States)

    Takano, T; Becker, L E

    1997-02-01

    The ependyma of the spinal central canal in cases of hydrocephalus shows abnormalities which vary with the aetiology of ventricular dilatation. To determine whether these ependymal changes are developmental or reactive in nature, immunohistochemical findings were compared between nine normal controls and 12 cases of hydrocephalus (three each of congenital aqueductal stenosis. Dandy-Walker malformation, Chiari type II malformation, and post-haemorrhagic hydrocephalus) using antisera to nestin, vimentin and glial fibrillary acidic protein. The main pathological findings were disruption of ependymal layer, apparent pseudostratification of ependyma, expansion, cleft or syrinx formation in relation to the central canal, and ependymal rosette formation. In normal developing fetal spinal cord, nestin and vimentin were expressed mainly in pseudostratified ependymal cells and radial fibres in the median septum. In cases with congenital hydrocephalus (congenital aqueductal stenosis. Dandy-Walker malformation, and Chiari type II malformation), nestin was overexpressed in immature ependymal cells, and strong vimentin immunoreactivity was detected in the long tract of radial fibres in the median septum. Nestin and vimentin were also expressed in small cells and their fibres which covered areas denuded of ependymal cells in cases of Chiari type II malformation and post-haemorrhagic hydrocephalus. Two conclusions are suggested by this report. First, the ependyma of the spinal central canal in congenital hydrocephalus shows a delay in maturation of radial glial cells into mature astrocytes and ependymal cells. Second, areas of ependymal denudation may be repaired by the immature glial cells derived from subependymal cells.

  11. COMMUNITY STRUCTURE AND DISTRIBUTION OF PELAGIC NANOFLAGELLATES AND CILIATES AND THEIR RELATIONSHIP WITH JELLYFISH OCCURRENCE IN SOUTHERN YELLOW SEA%黄海水母旺发区浮游鞭毛虫和纤毛虫群落结构分布及其与水母发生关系初探

    Institute of Scientific and Technical Information of China (English)

    丁军军; 徐奎栋

    2012-01-01

    The role of nanoflagellates and ciliates during jellyfish bloom remains unexplored. We investigated the changes of the community structure and distribution of planktonic nanoflagellates and ciliates collected from the transects E, G and I in the southern Yellow Sea in April and August of 2011. The nanoflagellates and ciliates were studied using DAPI epifluorescence microscopy and the quantitative protargol stain. The abundance of total nanoflagellates was high in the coastal area and decreased towards the offshore area, Vertically, nanoflagellates mainly distributed in the surface and near the bottom layers in water. Compared with those in spring, the total abundance and biomass of nanoflagellates in- creased in summer. The abundance of ciliates increased from inshore to offshore area. This was different from that of nan- oflagellates. Ciliates in the surface layer contributed up to 80% of total abundance and abruptly decreased below the 30 m depth. Compared with those in spring, the overall ciliate abundance and biomass decreased by about 50% in summer when jellyfish appeared. The ciliate abundance in summer was only 30%--40% of that in spring at transects E and G, while the ciliate abundance at the transect I, where there was no jellyfish observed, highly increased in summer. Jellyfish can cause direct and indirect changes to nano- and microzooplankton through cascading effects. The sharp decreases of ciliates at transects E and G were likely attributed to the predation pressure from increasing jellyfish, and consequently resulted in the increase of nanoflagellates. In contrast, ciliates increased at transect I without the impact of jellyfish.%鞭毛虫和纤毛虫在海洋微食物环和经典食物链间的能量流动中起着重要的枢纽作用,但其在水母暴发过程中的作用仍然不明。本研究基于2011年春季以及水母旺发的夏季黄海专项航次,通过荧光染色技术和定量蛋白银法研究了南黄海水母频发海域3

  12. Potential distribution of sycamore lace bug, Corythucha ciliate in China (Hemiptera : Tingidae)%悬铃木方翅网蝽在我国的潜在分布分析

    Institute of Scientific and Technical Information of China (English)

    朱耿平; 王晓静; 刘国卿; 卜文俊

    2012-01-01

    运用生态位模型MaxEnt和GARP对悬铃木方翅网蝽Corythucha ciliate (Say)在我国的潜在分布进行了模拟,并结合其寄主植物悬铃木在我国的分布进行了分析.实验采用悬铃木方翅网蝽在我国的分布数据,结合6种气候变量和海拔数据构建模型,并将MaxEnt和GARP的输出结果进行合意.研究显示MaxEnt和GARP的模拟结果基本一致,均能较好的模拟悬铃木方翅网蝽在我国的分布,二者均显示山东西南部和中部、四川中部和东部、重庆、陕西中部、河南中部和东部、安徽、江苏、上海、贵州、湖南、江西、浙江、福建中部和北部、云南中部等地区为悬铃木方翅网蝽的适宜分布区,此外,河北中部和南部、山东东部,广东和广西的北部亦具潜在分布的可能性.与MaxEnt输出结果相比,GARP相对较为保守.MaxEnt输出结果显示年平均气温和极端低温对悬铃木方翅网蝽地理分布的限制作用最大.考虑到该虫对高低温度的耐受性,我国二球悬铃木栽培的南界(南宁和广州)和北界(大连、北京、石家庄、太原)需要重视和监控起来.%Potential distribution of Corythucha ciliate (Say) in China were predicted using two ecological niche modelling algorithms (i.e. , MaxEnt and GARP). The models were calibrated using domestic records and 6 bioclimatic variables plus elevation. These potential distributions were then evaluated with respect to the distribution of pest host plant ( i. e. , Platanus spp. ). Significant variables associating with the bug' s occurrence were identified. Both models performed good discriminability compared to random prediction. Result of GARP was a little conservative compared to MaxEnt. High suitable areas identified by the consensus of two models including; southwestern and central Shandong, eastern and central Sichuan, Chongqing, central Shaanxi, eastern and central Henan, Anhui, Jiangsu, Shanghai, Guizhou, Hunan, Jiangxi, Zhejiang

  13. Novel method for isolation of murine clara cell secretory protein-expressing cells with traces of stemness.

    Directory of Open Access Journals (Sweden)

    Xiao-Yang Wang

    Full Text Available Clara cells are non-ciliated, secretory bronchiolar epithelial cells that serve to detoxify harmful inhaled substances. Clara cells also function as stem/progenitor cells for repair in the bronchioles. Clara cell secretory protein (CCSP is specifically expressed in pulmonary Clara cells and is widely used as a Clara cell marker. In addition CCSP promoter is commonly used to direct gene expression into the lung in transgenic models. The discovery of CCSP immunoreactivity in plasma membranes of airway lining cells prompted us to explore the possibility of enriching Clara cells by flow cytometry. We established a novel and simple method for the isolation of CCSP-expressing cell Clara cells using a combination of mechanical and enzymatic dissociation followed by flow cytometry sorting technology. We showed that ∼25% of dissociated cells from whole lung expressed CCSP. In the resulting preparation, up to 98% of cells expressed CCSP. Notably, we found that several common stem cell markers including CD44, CD133, Sca-1 and Sox2 were expressed in CCSP(+ cells. Moreover, CCSP(+ cells were able to form spheroid colonies in vitro with 0.97‰ efficiency. Parallel studies in vivo confirmed that a small population of CCSP(-expressing cells in mouse airways also demonstrates stem cell-like properties such as label retention and harboring rare bronchioalveolar stem cells (BASCs in terminal bronchioles (TBs. We conclude that CCSP(+ cells exhibit a number of stem cell-like features including stem cell marker expression, bronchosphere colony formation and self-renewal ability. Clara cell isolation by flow cytometry sorting is a useful method for investigating the function of primary Clara cells in stem cell research and mouse models.

  14. 汉中市兴元湖纤毛虫群落结构与水质评价%Study on Community Structure of Ciliates and Water Evaluation in Xingyuan Lake of Hanzhong

    Institute of Scientific and Technical Information of China (English)

    刘智峰

    2015-01-01

    2014年3~5月,利用PFU法对汉中市兴元湖水中纤毛虫群落进行调查,从3个采样点共观察到56种纤毛虫,隶属1门,3纲,11目,32属。优势种为纵长板壳虫(Coleps elonqatus)、钝漫游虫(Litonotus obtusus)、钩刺斜管虫(Chilodonella uncinata)、珍珠映毛虫(Cinetochilum margaritaceum)、沟钟虫(Vorti-cella convallaria)、尾瘦尾虫(Uroleptus candatus)、伪尖毛虫(Oxyticha fallax)、阔口游仆虫(Euplotes eurys-tomus)。通过计算水体纤毛虫的多样性指数,大小关系为3号采样点﹤1号采样点﹤2号采样点。水质评价结果,1号采样点属于β-中污型,2号采样点属于寡污型,3号采样点属于a-中污型。%The investigation on ciliates community and water quality assessment in Xingyuan Lake was carried out from April to May in 2014. Fifty-six species belonging to three classes of eleven orders of thirty genuses are discovered from three test sites. The dominant spices were Coleps elonqatus, Litonotus obtusus, Chilodonella uncinata, Cinetochilum margaritaceum, Vorticella convallaria, Uroleptus candatus, Oxyticha fallax and Euplotes eurystomus. Using species diversity index to assess water quality of Xingyuan Lake, the results showed that site one belonged to β-mesosaprobic zone; site two belonged to oligosaprobic zone; and site three belonged to a-mesosaprobic zone.

  15. Disruption of Bardet-Biedl syndrome ciliary proteins perturbs planar cell polarity in vertebrates.

    Science.gov (United States)

    Ross, Alison J; May-Simera, Helen; Eichers, Erica R; Kai, Masatake; Hill, Josephine; Jagger, Daniel J; Leitch, Carmen C; Chapple, J Paul; Munro, Peter M; Fisher, Shannon; Tan, Perciliz L; Phillips, Helen M; Leroux, Michel R; Henderson, Deborah J; Murdoch, Jennifer N; Copp, Andrew J; Eliot, Marie-Madeleine; Lupski, James R; Kemp, David T; Dollfus, Hélène; Tada, Masazumi; Katsanis, Nicholas; Forge, Andrew; Beales, Philip L

    2005-10-01

    The evolutionarily conserved planar cell polarity (PCP) pathway (or noncanonical Wnt pathway) drives several important cellular processes, including epithelial cell polarization, cell migration and mitotic spindle orientation. In vertebrates, PCP genes have a vital role in polarized convergent extension movements during gastrulation and neurulation. Here we show that mice with mutations in genes involved in Bardet-Biedl syndrome (BBS), a disorder associated with ciliary dysfunction, share phenotypes with PCP mutants including open eyelids, neural tube defects and disrupted cochlear stereociliary bundles. Furthermore, we identify genetic interactions between BBS genes and a PCP gene in both mouse (Ltap, also called Vangl2) and zebrafish (vangl2). In zebrafish, the augmented phenotype results from enhanced defective convergent extension movements. We also show that Vangl2 localizes to the basal body and axoneme of ciliated cells, a pattern reminiscent of that of the BBS proteins. These data suggest that cilia are intrinsically involved in PCP processes.

  16. Tracheal dysplasia precedes bronchial dysplasia in mouse model of N-nitroso trischloroethylurea induced squamous cell lung cancer.

    Directory of Open Access Journals (Sweden)

    Moumita Ghosh

    Full Text Available Squamous cell lung cancer (SCC is the second leading cause of lung cancer death in the US and has a 5-year survival rate of only 16%. Histological changes in the bronchial epithelium termed dysplasia are precursors to invasive SCC. However, the cellular mechanisms that cause dysplasia are unknown. To fill this knowledge gap, we used topical application of N-nitroso-tris chloroethylurea (NTCU for 32 weeks to induce squamous dysplasia and SCC in mice. At 32 weeks the predominant cell type in the dysplastic airways was Keratin (K 5 and K14 expressing basal cells. Notably, basal cells are extremely rare in the normal mouse bronchial epithelium but are abundant in the trachea. We therefore evaluated time-dependent changes in tracheal and bronchial histopathology after NTCU exposure (4, 8, 12, 16, 25 and 32 weeks. We show that tracheal dysplasia occurs significantly earlier than that of the bronchial epithelium (12 weeks vs. 25 weeks. This was associated with increased numbers of K5+/K14+ tracheal basal cells and a complete loss of secretory (Club cell secretory protein expressing CCSP+ and ciliated cells. TUNEL staining of NTCU treated tissues confirmed that the loss of CCSP+ and ciliated cells was not due to apoptosis. However, mitotic index (measured by bromodeoxyuridine incorporation showed that NTCU treatment increased proliferation of K5+ basal cells in the trachea, and altered bronchial mitotic population from CCSP+ to K5+ basal cells. Thus, we demonstrate that NTCU-induced lung epithelial dysplasia starts in the tracheal epithelium, and is followed by basal cell metaplasia of the bronchial epithelium. This analysis extends our knowledge of the NTCU-SCC model by defining the early changes in epithelial cell phenotypes in distinct airway locations, and this may assist in identifying new targets for future chemoprevention studies.

  17. Ecrg4 expression and its product augurin in the choroid plexus: impact on fetal brain development, cerebrospinal fluid homeostasis and neuroprogenitor cell response to CNS injury

    Directory of Open Access Journals (Sweden)

    Gonzalez Ana

    2011-01-01

    Full Text Available Abstract Background The content and composition of cerebrospinal fluid (CSF is determined in large part by the choroid plexus (CP and specifically, a specialized epithelial cell (CPe layer that responds to, synthesizes, and transports peptide hormones into and out of CSF. Together with ventricular ependymal cells, these CPe relay homeostatic signals throughout the central nervous system (CNS and regulate CSF hydrodynamics. One new candidate signal is augurin, a newly recognized 14 kDa protein that is encoded by esophageal cancer related gene-4 (Ecrg4, a putative tumor suppressor gene whose presence and function in normal tissues remains unexplored and enigmatic. The aim of this study was to explore whether Ecrg4 and its product augurin, can be implicated in CNS development and the response to CNS injury. Methods Ecrg4 gene expression in CNS and peripheral tissues was studied by in situ hybridization and quantitative RT-PCR. Augurin, the protein encoded by Ecrg4, was detected by immunoblotting, immunohistochemistry and ELISA. The biological consequence of augurin over-expression was studied in a cortical stab model of rat CNS injury by intra-cerebro-ventricular injection of an adenovirus vector containing the Ecrg4 cDNA. The biological consequences of reduced augurin expression were evaluated by characterizing the CNS phenotype caused by Ecrg4 gene knockdown in developing zebrafish embryos. Results Gene expression and immunohistochemical analyses revealed that, the CP is a major source of Ecrg4 in the CNS and that Ecrg4 mRNA is predominantly localized to choroid plexus epithelial (CPe, ventricular and central canal cells of the spinal cord. After a stab injury into the brain however, both augurin staining and Ecrg4 gene expression decreased precipitously. If the loss of augurin was circumvented by over-expressing Ecrg4 in vivo, BrdU incorporation by cells in the subependymal zone decreased. Inversely, gene knockdown of Ecrg4 in developing

  18. A novel mouse model reveals that polycystin-1 deficiency in ependyma and choroid plexus results in dysfunctional cilia and hydrocephalus.

    Directory of Open Access Journals (Sweden)

    Claas Wodarczyk

    Full Text Available Polycystin-1 (PC-1, the product of the PKD1 gene, mutated in the majority of cases of Autosomal Dominant Polycystic Kidney Disease (ADPKD, is a very large (approximately 520 kDa plasma membrane receptor localized in several subcellular compartments including cell-cell/matrix junctions as well as cilia. While heterologous over-expression systems have allowed identification of several of the potential biological roles of this receptor, its precise function remains largely elusive. Studying PC-1 in vivo has been a challenging task due to its complexity and low expression levels. To overcome these limitations and facilitate the study of endogenous PC-1, we have inserted HA- or Myc-tag sequences into the Pkd1 locus by homologous recombination. Here, we show that our approach was successful in generating a fully functional and easily detectable endogenous PC-1. Characterization of PC-1 distribution in vivo showed that it is expressed ubiquitously and is developmentally-regulated in most tissues. Furthermore, our novel tool allowed us to investigate the role of PC-1 in brain, where the protein is abundantly expressed. Subcellular localization of PC-1 revealed strong and specific staining in ciliated ependymal and choroid plexus cells. Consistent with this distribution, we observed hydrocephalus formation both in the ubiquitous knock-out embryos and in newborn mice with conditional inactivation of the Pkd1 gene in the brain. Both choroid plexus and ependymal cilia were morphologically normal in these mice, suggesting a role for PC-1 in ciliary function or signalling in this compartment, rather than in ciliogenesis. We propose that the role of PC-1 in the brain cilia might be to prevent hydrocephalus, a previously unrecognized role for this receptor and one that might have important implications for other genetic or sporadic diseases.

  19. Role of non-neuronal cells in body weight and appetite control

    Directory of Open Access Journals (Sweden)

    Pilar eArgente-Arizón

    2015-03-01

    Full Text Available The brain is composed of neurons and non-neuronal cells, with the latter encompassing glial, ependymal and endothelial cells, as well as pericytes and progenitor cells. Studies aimed at understanding how the brain operates have traditionally focused on neurons, but the importance of non-neuronal cells has become increasingly evident. Once relegated to supporting roles, it is now indubitable that these diverse cell types are fundamental for brain development and function, including that of metabolic circuits and they may play a significant role in obesity onset and complications. They participate in processes of neurogenesis, synaptogenesis and synaptic plasticity of metabolic circuits both during development and in adulthood. Some glial cells, such as tanycytes and astrocytes, transport circulating nutrients and metabolic factors that are fundamental for neuronal viability and activity into and within the hypothalamus. All of these cell types express receptors for a variety of metabolic factors and hormones, suggesting that they participate in metabolic function. They are the first line of defense against any assault to neurons. Indeed, microglia and astrocytes participate in the hypothalamic inflammatory response to high fat diet (HFD-induced obesity, with this process contributing to inflammatory related insulin and leptin resistance. Moreover, HFD-induced obesity and hyperleptinemia modify hypothalamic astroglial morphology, which is associated with changes in the synaptic inputs to neuronal metabolic circuits. Astrocytic contact with the microvasculature is increased by HFD intake and this could modify nutrient/hormonal uptake into the brain. In addition, progenitor cells in the hypothalamus are now known to have the capacity to renew metabolic circuits and this can be affected by HFD intake and obesity. Here we discuss our current understanding of how non-neuronal cells participate in physiological and physiopathological metabolic control.

  20. Role of Non-Neuronal Cells in Body Weight and Appetite Control

    Science.gov (United States)

    Argente-Arizón, Pilar; Freire-Regatillo, Alejandra; Argente, Jesús; Chowen, Julie A.

    2015-01-01

    The brain is composed of neurons and non-neuronal cells, with the latter encompassing glial, ependymal and endothelial cells, as well as pericytes and progenitor cells. Studies aimed at understanding how the brain operates have traditionally focused on neurons, but the importance of non-neuronal cells has become increasingly evident. Once relegated to supporting roles, it is now indubitable that these diverse cell types are fundamental for brain development and function, including that of metabolic circuits, and they may play a significant role in obesity onset and complications. They participate in processes of neurogenesis, synaptogenesis, and synaptic plasticity of metabolic circuits both during development and in adulthood. Some glial cells, such as tanycytes and astrocytes, transport circulating nutrients and metabolic factors that are fundamental for neuronal viability and activity into and within the hypothalamus. All of these cell types express receptors for a variety of metabolic factors and hormones, suggesting that they participate in metabolic function. They are the first line of defense against any assault to neurons. Indeed, microglia and astrocytes participate in the hypothalamic inflammatory response to high fat diet (HFD)-induced obesity, with this process contributing to inflammatory-related insulin and leptin resistance. Moreover, HFD-induced obesity and hyperleptinemia modify hypothalamic astroglial morphology, which is associated with changes in the synaptic inputs to neuronal metabolic circuits. Astrocytic contact with the microvasculature is increased by HFD intake and this could modify nutrient/hormonal uptake into the brain. In addition, progenitor cells in the hypothalamus are now known to have the capacity to renew metabolic circuits, and this can be affected by HFD intake and obesity. Here, we discuss our current understanding of how non-neuronal cells participate in physiological and physiopathological metabolic control. PMID:25859240

  1. Staurosporine-induced cell death in Tetrahymena thermophila has mixed characteristics of both apoptotic and autophagic degeneration

    DEFF Research Database (Denmark)

    Christensen, S T; Chemnitz, J; Straarup, E M;

    1998-01-01

    phosphorylation of the PKC-specific substrate, myelin basic protein fragment 4-14. Our results show that cell death in the presence of staurosporine is associated with morphological and ultrastructural changes similar to both apoptosis and autophagic degeneration, but these in turn can be postponed or prevented......Staurosporine blocks signal transduction associated with cell survival, proliferation and chemosensory behaviour in the ciliated protozoan, Tetrahymena thermophila. Staurosporine inhibits cell proliferation and in vivo protein phosphorylation induced by phorbol ester. It also reduces the in vitro...... by 8-bromo-cyclic GMP, protoporphyrin IX, hemin or actinomycin D, although phorbol ester and insulin were ineffective. The results support the notion that staurosporine-induced cell death is an active process, associated with and/or requiring de novo RNA synthesis....

  2. Purinergic signalling in a latent stem cell niche of the rat spinal cord.

    Science.gov (United States)

    Marichal, Nicolás; Fabbiani, Gabriela; Trujillo-Cenóz, Omar; Russo, Raúl E

    2016-06-01

    The ependyma of the spinal cord harbours stem cells which are activated by traumatic spinal cord injury. Progenitor-like cells in the central canal (CC) are organized in spatial domains. The cells lining the lateral aspects combine characteristics of ependymocytes and radial glia (RG) whereas in the dorsal and ventral poles, CC-contacting cells have the morphological phenotype of RG and display complex electrophysiological phenotypes. The signals that may affect these progenitors are little understood. Because ATP is massively released after spinal cord injury, we hypothesized that purinergic signalling plays a part in this spinal stem cell niche. We combined immunohistochemistry, in vitro patch-clamp whole-cell recordings and Ca(2+) imaging to explore the effects of purinergic agonists on ependymal progenitor-like cells in the neonatal (P1-P6) rat spinal cord. Prolonged focal application of a high concentration of ATP (1 mM) induced a slow inward current. Equimolar concentrations of BzATP generated larger currents that reversed close to 0 mV, had a linear current-voltage relationship and were blocked by Brilliant Blue G, suggesting the presence of functional P2X7 receptors. Immunohistochemistry showed that P2X7 receptors were expressed around the CC and the processes of RG. BzATP also generated Ca(2+) waves in RG that were triggered by Ca(2+) influx and propagated via Ca(2+) release from internal stores through activation of ryanodine receptors. We speculate that the intracellular Ca(2+) signalling triggered by P2X7 receptor activation may be an epigenetic mechanism to modulate the behaviour of progenitors in response to ATP released after injury.

  3. Sex determination: ciliates' self-censorship.

    Science.gov (United States)

    Bloomfield, Gareth

    2014-07-07

    Differentiation involves the expression of certain latent cellular characteristics and the repression of others. A new study has revealed how Paramecium uses short RNAs to delete information from the somatic genome of one of its two sexes.

  4. Ciliates as engineers of phototrophic biofilms

    NARCIS (Netherlands)

    Weerman, Ellen J.; van der Geest, Harm G.; van der Meulen, Myra D.; Manders, Erik M. M.; van de Koppel, Johan; Herman, Peter M. J.; Admiraal, Wim

    2011-01-01

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the 'engineering' effect

  5. Ciliates as engineers of phototrophic biofilms.

    NARCIS (Netherlands)

    Weerman, E.J.; Geest, H.G.; Meulen, M.D.; Manders, E.M.M.; Van de Koppel, J.; Herman, P.M.J.; Admiraal, W.

    2011-01-01

    1.Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the ‘engineering’ effects

  6. Ciliates as engineers of phototrophic biofilms.

    NARCIS (Netherlands)

    Weerman, E.J.; van der Geest, H.G.; van der Meulen, M.D; Manders, E.M.M.; van de Koppel, J.; Herman, P.M.J.; Admiraal, W.

    2011-01-01

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the ‘engineering’ effect

  7. Using the Ciliate Protozoan Vorticella in Teaching.

    Science.gov (United States)

    Jones, Alick R.

    1980-01-01

    Describes methods for collection, culture, observation, and making permanent stained preparations of the protozoan vorticella. Suggestions are made for experiments to investigate growth, reproduction, settlement, ecology, feeding, and osmoregulation. (CS)

  8. GABAρ subunits confer a bicuculline-insensitive component to GFAP+ cells of cerebellum

    Science.gov (United States)

    Pétriz, Adriana; Reyes-Haro, Daniel; González-González, María Alejandra; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2014-01-01

    GABA-A receptors mediating synaptic or extrasynaptic transmission are molecularly and functionally distinct, and glial cells are known to express a plethora of GABA-A subunits. Here we demonstrate that GFAP+ cells of the granular layer of cerebellum express GABAρ subunits during early postnatal development, thereby conferring peculiar pharmacologic characteristics to GABA responses. Electron microscopy revealed the presence of GABAρ in the plasma membrane of GFAP+ cells. In contrast, expression in the adult was restricted to Purkinje neurons and a subset of ependymal cells. Electrophysiological studies in vitro revealed that astrocytes express functional receptors with an EC50 of 52.2 ± 11.8 μM for GABA. The evoked currents were inhibited by bicuculline (100 μM) and TPMPA (IC50, 5.9 ± 0.6 μM), indicating the presence of a GABAρ component. Coimmunoprecipitation demonstrated protein–protein interactions between GABAρ1 and GABAα1, and double immunofluorescence showed that these subunits colocalize in the plasma membrane. Three populations of GABA-A receptors in astrocytes were identified: classic GABA-A, bicuculline-insensitive GABAρ, and GABA-A–GABAρ hybrids. Clusters of GABA-A receptors were distributed in the perinuclear space and along the processes of GFAP+ cells. Time-lapse microscopy showed GABAρ2-GFP accumulation in clusters located in the soma and along the processes. The clusters were relatively immobile, with mean displacement of 9.4 ± 0.9 μm and a net distance traveled of 1–2 μm, owing mainly to directional movement or simple diffusion. Modulation of GABAρ dynamics may be a novel mechanism of extrasynaptic transmission regulating GABAergic control of GFAP+ cells during early postnatal development. PMID:25422464

  9. PCR-based detection of a rare linear DNA in cell culture

    Directory of Open Access Journals (Sweden)

    Saveliev Sergei V.

    2002-01-01

    Full Text Available The described method allows for detection of rare linear DNA fragments generated during genomic deletions. The predicted limit of the detection is one DNA molecule per 107 or more cells. The method is based on anchor PCR and involves gel separation of the linear DNA fragment and chromosomal DNA before amplification. The detailed chemical structure of the ends of the linear DNA can be defined with the use of additional PCR-based protocols. The method was applied to study the short-lived linear DNA generated during programmed genomic deletions in a ciliate. It can be useful in studies of spontaneous DNA deletions in cell culture or for tracking intracellular modifications at the ends of transfected DNA during gene therapy trials.

  10. A novel DNA deletion-ligation reaction catalyzed in vitro by a developmentally controlled activity from Tetrahymena cells.

    Science.gov (United States)

    Robinson, E K; Cohen, P D; Blackburn, E H

    1989-09-08

    Developmentally controlled genomic deletion-ligations occur during ciliate macronuclear differentiation. We have identified a novel activity in Tetrahymena cell-free extracts that efficiently catalyzes a specific set of intramolecular DNA deletion-ligation reactions. When synthetic DNA oligonucleotide substrates were used, all the deletion-ligation products resembled those formed in vivo in that they resulted from deletions between pairs of short direct repeats. The reaction is ATP-dependent, salt-sensitive, and strongly influenced by the oligonucleotide substrate sequence. The deletion-ligation activity has an apparent size of 200-500 kd, no nuclease-sensitive component, and is highly enriched in cells developing new macronuclei. The temperature inactivation profile of the activity parallels the temperature lethality profile specific for Tetrahymena cells developing new macronuclei. We suggest that this deletion-ligation activity carries out the genomic deletions in developing macronuclei in vivo.

  11. Resistance of subventricular neural stem cells to chronic hypoxemia despite structural disorganization of the germinal center and impairment of neuronal and oligodendrocyte survival

    Science.gov (United States)

    d’Anglemont de Tassigny, Xavier; Sirerol-Piquer, M Salomé; Gómez-Pinedo, Ulises; Pardal, Ricardo; Bonilla, Sonia; Capilla-Gonzalez, Vivian; López-López, Ivette; De la Torre-Laviana, Francisco Javier; García-Verdugo, José Manuel; López-Barneo, José

    2015-01-01

    Chronic hypoxemia, as evidenced in de-acclimatized high-altitude residents or in patients with chronic obstructive respiratory disorders, is a common medical condition that can produce serious neurological alterations. However, the pathogenesis of this phenomenon is unknown. We have found that adult rodents exposed for several days/weeks to hypoxia, with an arterial oxygen tension similar to that of chronically hypoxemic patients, manifest a partially irreversible structural disarrangement of the subventricular neurogenic niche (subventricular zone) characterized by displacement of neurons and myelinated axons, flattening of the ependymal cell layer, and thinning of capillary walls. Despite these abnormalities, the number of neuronal and oligodendrocyte progenitors, neuroblasts, and neurosphere-forming cells as well as the proliferative activity in subventricular zone was unchanged. These results suggest that neural stem cells and their undifferentiated progeny are resistant to hypoxia. However, in vivo and in vitro experiments indicate that severe chronic hypoxia decreases the survival of newly generated neurons and oligodendrocytes, with damage of myelin sheaths. These findings help explain the effects of hypoxia on adult neurogenesis and provide new perspectives on brain responsiveness to persistent hypoxemia. PMID:27774479

  12. 甘肃徽县水阳江铅锌污染段纤毛虫群落特征及对水质的评价%Community Characteristics of Ciliates and Water Quality Assessment in the Pb-Zn-Contaminated Section of the Shuiyangjiang River in Huixian County,Gansu Province

    Institute of Scientific and Technical Information of China (English)

    马正学; 贺鹏辉; 杨镇; 宁应之

    2009-01-01

    2006年10月至2008年5月,在甘肃徽县水阳江铅锌污染段选择4个样点,分别在3个水期采集水样,研究了纤毛虫物种多样性及群落结构.共鉴定到纤毛虫52种,隶属于3纲12目29科33属.利用纤毛虫群落特征指标对水阳江铅锌污染段的水质进行了初步评价.综合评价结果显示,4个样点受污染程度为县城>厂区>牟坝>对照,污染级别为中度至重度.初步筛选出瓜形膜袋虫(Cyclidium citrullus)、尾草履虫(Paramoecium caudatum)、薄漫游虫(Litonotus lamella)作为铅锌污染水体的指示物种.%Species diversity and community structure of ciliates in the Pb-Zn-Contaminated section of the Shuiyangjiang River were studied during the period from October 2006 to May 2008,using water samples collected from 4 sampling sites in that section in 3 different periods.In the water samples,52 species of ciliates,sorted into 3 classes,12 orders,29 family and 33 genus,were identified,based on which water quality of that section of the Shuiyangjiang River was preliminarily evaluated.Results show that pollution of the water varied in degree between the four sampling sites in the section,following a decreasing order of Xiancheng>Changqu>Muba>Duizhao,from severe to moderate.Ciliates of Cyclidium citrullus,Paramecium caudatum,and Litonotus lamella were screened out to be indicators of Pb-Zn-contamination of water bodies.

  13. 广东沿海的砂壳纤毛虫及3种国内新纪录%TINTINNID CILIATES FROM COASTAL WATERS OFF GUANGDONG, WITH NOTES ON THREE NEW RECORDS OF CHINA (PROTOZOA, CILIOPHORA)

    Institute of Scientific and Technical Information of China (English)

    张伟; 姜勇; 李继秋; 马洪钢; 许恒龙

    2012-01-01

    Tintinnid ciliates are an important component of plankton communities and widely distribute in the coastal waters. However, in morphological studies, the tintinnids belonged to the poorly known groups, especially in the water of the South China Sea. In the winter of 2008, the tintinnids sampled from the coastal waters in the South China Sea (Guangdong) were investigated. The water temperature was 17-20℃ and the salinity was about 30‰-31‰. Samples were collected by a horizontal tow net from 1.5 m under the water surface. Part of samples were immediately stored in 4℃ for in vivo observation and the others were fixed in formalin at a final concentration of 5% for future observations of lorica characteristics. The morphological characteristics including lorica features were observed and described by using light microscopical method. In this present study, 16 species were indentified and they belonged to Tintinnopsis, Codonella, Stenosemella and Favella. Three of them were believed to be the first records of China, Codonella apicata Kofoid & Campbell, 1929, Tintinnopsis turbo Meunier, 1919 and Stenosemella expansa Wailes, 1925. In addition, another three species were the first records in the semi-tropical and tropical areas of China, Tintinnopsis tubulosoides Meunier, 1910; Tintinnopsis lohmanni (Jorgensen, 1927) Laackmann, 1906, and Codonella rapa Kofoid & Campbell, 1929. The other 10 species included Tintinnopsis beroidea Stein, 1867, Tintinnopsis acuminata (Daday, 1887) Kofoid & Campbell, 1929, Tintinnopsis tocantinensis Kofoid & Campbell, 1929, Tintinnopsis tubulosoides Meunier, 1910, Tintinnopsis tublosa Levander, 1900, Tintinnopsis clongata Daday, 1887, Tintinnopsis lohmanni (Jorgensen, 1927) Laackmann,, 1906, Stenosemella parvicollis (Marshall, 1934) Hada, 1935, Favella campanula (Schmidt, 1901)J(o)rgensen, 1924, and Codonella rapa Kofoid & Campbell, 1929.%对广东沿海的砂壳纤毛虫进行了初步研究,涉及7属16种,其中3种确定为中

  14. Structure and occurrence of cyphonautes larvae (Bryozoa, Ectoprocta)

    DEFF Research Database (Denmark)

    Nielsen, Claus; Worsaae, Katrine

    2010-01-01

    . membranacea larva. The velum carries two rows of ciliated cells, though the lower "row" consists of only one or two cells. Both rows of ciliated cells are innervated by nerves, which have not been detected in the M. membranacea larva. The ciliated ridge of H. malayensis lacks the frontal cilia...

  15. An astrocyte regenerative response from vimentin-containing cells in the spinal cord of amyotrophic lateral sclerosis's disease-like transgenic (G93A SOD1) mice.

    Science.gov (United States)

    Zhou, Yiyi; Lu, Yi; Fang, Xin; Zhang, Jie; Li, Jiao; Li, Shujuan; Deng, Xia; Yu, Yaqing; Xu, Renshi

    2015-01-01

    The reason for regeneration in the adult spinal cord during motor neuron degeneration in amyotrophic lateral sclerosis (ALS) remains largely unknown. To this end, we studied the alteration of vimentin (a neural precursor cells marker in CNS)-containing cells (VCCs) in spinal cord during different stages of ALS used C57BL/6J G93A SOD1 transgenic mice mimicking ALS. Results showed that VCCs were mostly distributed in the ependymal zone (EZ) surrounding the central canal of spinal cord in SOD1 wild type mice; a few of VCCs were sparsely distributed in other regions. However, the number of VCCs significantly increased in the spinal cord during the onset and progression stages of ALS. They were extensively distributed in the EZ, the anterior, the lateral and the posterior horn of grey matter, particularly in the posterior horn region at the progression stage. A majority of VCCs in the anterior, the lateral and the posterior horn of grey matter (outside of EZ) generated astrocytes, but no neurons, oligodendrocytes and microgliocytes. Our results suggested that there was a potential astrocyte regenerative response to motor neuron degeneration in motor neurons-degenerated regions in the adult spinal cord during the onset and progression stages of ALS-like disease. The regenerative responses in the adult spinal cord of ALS-like mice may be a potential pathway in attempting to repair the degenerated motor neurons and restore the dysfunctional neural circuitry.

  16. 大鼠脊髓中央管室管膜上皮细胞及其分泌吸收的超微形态特征%Ultrastructural characteristics of ependymal cells on the central canal of the spinal cord and their secretion and absorptive function in rats

    Institute of Scientific and Technical Information of China (English)

    吴淑玉; 郭艳苏; 杨程; 吴东霞; 李向印; 李春岩; 雷建章

    2004-01-01

    应用透射电子显微镜研究大鼠脊髓中央管室管膜上皮细胞及其在分泌和吸收过程中的超微结构特点,并分析其与脑脊液循环的相互关系.结果显示:大鼠脊髓中央管室管膜上皮主要为假复层柱状上皮,其柱形细胞游离端具有纤毛和微绒毛,因其多寡不同,又分为纤毛上皮细胞和无纤毛上皮细胞,其中纤毛上皮细胞数量相对较少,但二者游离面皆可见到数量不等的微顶浆分泌现象及吞饮小泡.以上结果提示脊髓中央管室管膜上皮细胞可能在脑脊液的分泌和重吸收过程中,发挥积极的生物学作用.

  17. Acquisition of cell polarity during cell cycle and oral replacement in Tetrahymena.

    Science.gov (United States)

    Kaczanowska, Janina; Kaczanowski, Szymon; Kiersnowska, Mauryla; Fabczak, Hanna; Tulodziecka, Karolina; Kaczanowski, Andrzej

    2008-01-01

    The aim of this study was to search for a mechanism responsible for the acquisition of cell polarity in a ciliate Tetrahymena. Homologs of the mammalian genes coding for CDC42-GSK3beta- MARK/PAR1-MAPs proteins were found in the Tetrahymena genome (Eisen et al., 2006, and this study). These proteins belong to a pathway which controls assembly and disassembly of microtubule bundles and cell polarity in neural cells. In Tetrahymena, there are two types of morphogenesis: divisional and oral replacement (OR). In divisional morphogenesis, an elongation of longitudinal microtubule bundles (LMs) takes place during cell division. In contrast, in OR type morphogenesis, which occurs in starved non-dividing cells, a polar retraction of LMs occurs. In T. pyriformis, the frequency of developmental switch to OR morphogenesis increases in the presence of wortmannin, an inhibitor of the CDC42-GSK3beta-MARK pathway. In contrast, wortmannin when applied to dividing cells does not affect divisional morphogenesis. Using immunostaining with the antibody against mammalian mitotic phosphoproteins (MPM-2) we show that these proteins co-localize with the LMs and are distributed along the anterior-posterior gradient. In addition, we show that during OR type morphogenesis, the fate of LMs correlates with the anterior-posterior gradient of instability of the cortical structures. We used the conditional mouth-less mutant of T. thermophila (Tiedtke et al., 1988) to test if the presence of the oral apparatus is required for the maintenance of cell polarity. We discuss our results in relation to the hypothesis of GSK3-beta-MARK pathway involvement in the acquisition of cell polarity in Tetrahymena.

  18. Studies on the cortical morphogenesis during cell division in Halteria grandinella (Muller, 1773) (Ciliophora, Oligotrichida)

    Science.gov (United States)

    Song, Weibo

    1993-06-01

    Morphogenesis during cell division was investigated in oligotrichous ciliate, Halteria grandinella utilizing protargol impregnated specimens. The cortical morphogenetical pattern of Halteria grandinella is generally similar to that given by Fauré-Fremiet. The proter inherits the parental adoral zone of membranelles (AZM) apparently unchanged; in the opisthe the oral primordium develops de novo from a single. AZM-anlage; somatic cirri for both the proter and opisthe are separately differentiated from 10 (seldom 9) cirral primordia that originate de novo from 10 latitudinal developmental analagen. The anlage of paroral membrane of opisthe forms just to the right of the posterior end of the oral primordium. Each streak of cirral primordia develops 4 groups of basal body pairs: both of the anterior two consist of only one pair of basal bodies, on the contrary, each of the last two groups has 2 basal body pairs.

  19. The mammalian neocortical pyramidal cell: a new theory on prenatal development

    Directory of Open Access Journals (Sweden)

    Miguel eMarín-Padilla

    2014-01-01

    Full Text Available Mammals’ new cerebral cortex (neocortex and the new type of pyramidal neuron are mammalian innovations that have evolved for operating their increasing motor capabilities using essentially analogous anatomical and neural makeups. The human neocortex starts to develop in the 6-week-old embryo with the establishment of a primordial cortical organization that resembles the primitive cortices of amphibian and reptiles that operated his early motor activities. From the 8th to the 15th week of age, the new pyramidal neurons, of ependymal origin, are progressively incorporated within this primordial cortex forming a cellular plate that divide its components into those above it (neocortex first lamina and those below it (neocortex subplate elements. From the 16th week of age to birth and postnatally, the new pyramidal neurons continue to elongate functionally their apical dendrite by adding synaptic membrane to incorporate the needed sensory information for operating the animal muscular activities. The new pyramidal neuron’ distinguishing feature is the capacity of elongating anatomically and functionally its apical dendrite (its main receptive surface without losing its original attachment to first lamina or the location of its soma retaining its essential nature. The number of pyramidal cell functional strata established in the motor cortex increases and reflects each mammalian species motor capabilities: the hedgehog needs 2 pyramidal cell functional strata to carry out all its motor activities, the mouse three, cat four, primates 5 and humans 6. The presence of six pyramidal cell functional strata distinguish the human motor cortex from that of others primates. Homo sapiens represent a new evolutionary stage that have transformed his primate brain for operating his unique motor capabilities, such as speaking, writing, painting, sculpturing including thinking as a premotor activity.

  20. Immunocytochemical localization of zinc transporter 3 in the ependyma of the mouse spinal cord.

    Science.gov (United States)

    Danscher, Gorm; Wang, Zhanyou; Kim, Yong Kuk; Kim, Sung Joo; Sun, Yuanjie; Jo, Seung Mook

    2003-05-15

    We report, for the first time, the light microscopical and ultrastructural appearance of ZnT3-immunoreactivities in the ependymal cells of the central canal of the mouse spinal cord. Light microscopy revealed the presence of ZnT3-immunoreactive (Ir) ependymal cells in 1 microm thick epon sections stained by the ABC method. The ZnT3-Ir cells were observed at all levels of the spinal cord, but were a little more numerous in lumbosacral segments than in cervicothoracic segments. The ZnT3-Ir cells had large, ovoid nuclei with abundant cytoplasm, and protruded into the lumen of the central canal. Our ultrastructural findings suggest that the ZnT3-Ir ependymal cells possess secretory activity directed towards the central canal. We propose that they may play a role in the trans-ependymal mechanism responsible for zinc homeostasis between cerebrospinal fluid and the central area of the gray matter.

  1. Ependyma of the central canal of the rat spinal cord: a light and transmission electron microscopic study.

    OpenAIRE

    Bruni, J.E.; Reddy, K

    1987-01-01

    Ependymal cells of the rat central canal were examined with a view to identifying features that distinguish them regionally and from their counterparts elsewhere in the ventricular system. The results revealed that the lining consisted for the most part of a pseudostratified layer of uniformly organised cuboidal to columnar ependymal cells present in largest numbers in lumbar and sacral segments and in the conus. Two cell variants were identified on the basis of the presence or absence of a r...

  2. Cell-in-Shell Hybrids: Chemical Nanoencapsulation of Individual Cells.

    Science.gov (United States)

    Park, Ji Hun; Hong, Daewha; Lee, Juno; Choi, Insung S

    2016-05-17

    Nature has developed a fascinating strategy of cryptobiosis ("secret life") for counteracting the stressful, and often lethal, environmental conditions that fluctuate sporadically over time. For example, certain bacteria sporulate to transform from a metabolically active, vegetative state to an ametabolic endospore state. The bacterial endospores, encased within tough biomolecular shells, withstand the extremes of harmful stressors, such as radiation, desiccation, and malnutrition, for extended periods of time and return to a vegetative state by breaking their protective shells apart when their environment becomes hospitable for living. Certain ciliates and even higher organisms, for example, tardigrades, and others are also found to adopt a cryptobiotic strategy for survival. A common feature of cryptobiosis is the structural presence of tough sheaths on cellular structures. However, most cells and cellular assemblies are not "spore-forming" and are vulnerable to the outside threats. In particular, mammalian cells, enclosed with labile lipid bilayers, are highly susceptible to in vitro conditions in the laboratory and daily life settings, making manipulation and preservation difficult outside of specialized conditions. The instability of living cells has been a main bottleneck to the advanced development of cell-based applications, such as cell therapy and cell-based sensors. A judicious question arises: can cellular tolerance against harmful stresses be enhanced by simply forming cell-in-shell hybrid structures? Experimental results suggest that the answer is yes. A micrometer-sized "Iron Man" can be generated by chemically forming an ultrathin (cell. Since the report on silica nanoencapsulation of yeast cells, in which cytoprotective yeast-in-silica hybrids were formed, several synthetic strategies have been developed to encapsulate individual cells in a cytocompatible fashion, mimicking the cryptobiotic cell-in-shell structures found in nature, for example

  3. Níveis de proteína degradável para novilhas em crescimento sobre a concentração de protozoários ciliados e outros parâmetros ruminais Levels of degradable protein given to heifers for the ciliate protozoa concentration and other ruminal parameters

    Directory of Open Access Journals (Sweden)

    Joaquim Balcells

    2001-05-01

    Full Text Available Em um ensaio de controle de parâmetros ruminais (pH, ritmo de trânsito (%h, volume ruminal (l, e concentração de protozoários ciliados, foram utilizadas quatro novilhas Holstein, canuladas no rúmen e duodeno, recebendo dietas com 4 níveis de proteína degradável, sem suplementar ou suplementadas com 25, 50 e 75 gramos de proteína degradável por quilo de concentrado em forma de uréia e caseína (98,2 e 93,2% de matéria orgânica e proteína bruta, respectivamente. As rações experimentais foram compostas por 25% de palha de cevada sem tratar e 75% de concentrado formulado em base a diferentes proporções (25/75 e 75/25 de milho/cevada, com 5% de resíduo de trigo e 5% de suplemento vitamínico mineral. Uma contínua infusão de marcador de fluxo de fase líquida (Cr-EDTA foi executada. Os oito tratamentos experimentais (2 dietas x 4 níveis de infusão foram administrados em 8 períodos de balanço em um delineamento cross-over, em esquema fatorial. O nível de infusão de N degradável afetou de forma significativa os valores médios ponderados de pH, que decresceram ao aumentar a suplementação (p 3/mL que de cevada (59,5 x 103/mL; p Entodinium alcançou 87,8% da população total. O gênero Epidinium apresentou menores valores com a dieta de cevada (3,73 vs. 1,89x103/mL, p 3/mL, p 5/mL, p In this experiment four Holstein heifers fitted with rumen and duodenum canulae were utilized to evaluate the rumen parameters as pH, passage rate (%/h, volume (L and ciliated protozoa concentration, when fed diets with four levels of rumen degradable protein. This was achieved supplementing 0, 25, 50 or 75 grams of degradable protein per kg of concentrate as a urea and casein (98.2% OM and 93.2% CP. The diets had 25% of barley straw without treatment and 75% concentrate formulated to contain different proportions (25/75 and 75/25 of corn and barley and also 5% of wheat residue and 5% of mineral and vitamin supplement. A continuous infusion of

  4. De novo centriole formation in human cells is error-prone and does not require SAS-6 self-assembly.

    Science.gov (United States)

    Wang, Won-Jing; Acehan, Devrim; Kao, Chien-Han; Jane, Wann-Neng; Uryu, Kunihiro; Tsou, Meng-Fu Bryan

    2015-11-26

    Vertebrate centrioles normally propagate through duplication, but in the absence of preexisting centrioles, de novo synthesis can occur. Consistently, centriole formation is thought to strictly rely on self-assembly, involving self-oligomerization of the centriolar protein SAS-6. Here, through reconstitution of de novo synthesis in human cells, we surprisingly found that normal looking centrioles capable of duplication and ciliation can arise in the absence of SAS-6 self-oligomerization. Moreover, whereas canonically duplicated centrioles always form correctly, de novo centrioles are prone to structural errors, even in the presence of SAS-6 self-oligomerization. These results indicate that centriole biogenesis does not strictly depend on SAS-6 self-assembly, and may require preexisting centrioles to ensure structural accuracy, fundamentally deviating from the current paradigm.

  5. Ultrastructure of the mouse spinal cord ependyma.

    OpenAIRE

    Bjugn, R; Haugland, H K; Flood, P R

    1988-01-01

    This study was done in order to investigate the normal ultrastructure of well-preserved mouse spinal canal ependyma using light, scanning and transmission electron microscopy. The ependymal lining was found to consist of a simple, cuboidal epithelium essentially similar to the unspecialized cuboidal ependyma of the brain ventricles. Apart from great variation in kinociliary density, no intracellular difference was noted between the ependymal cells. In contrast to earlier findings, indications...

  6. Immunohistochemical demonstration of Clara cell antigen in lung tumors of bronchiolar origin induced by N-nitrosodiethylamine in Syrian golden hamsters.

    Science.gov (United States)

    Rehm, S.; Takahashi, M.; Ward, J. M.; Singh, G.; Katyal, S. L.; Henneman, J. R.

    1989-01-01

    Both alveolar type II cells and Clara cells have been suggested as cells of origin of human bronchioloalveolar lung carcinomas and other pulmonary neoplasms, based on the presence of cell specific markers identified by immunocytochemical methods. Alveolar type II cell origin of solid and papillary lung tumors of the mouse has been demonstrated, and Clara cells have been suggested as cell of origin for hamster pulmonary neoplasms. Therefore, chemically induced bronchiolar hyperplasias and pulmonary neoplasms of Syrian golden hamsters were analyzed by avidin-biotin immunohistochemistry to localize a hamster-specific Clara cell antigen (CCA) and keratin. The hamsters had been treated subcutaneously with multiple doses of N-nitrosodiethylamine (NDEA). Proliferative lesions of low cuboidal, tall columnar, or pleomorphic cells were present within bronchioles or adjacent to airways in the alveolar parenchyma. Frequently areas of squamous cell differentiation were present focally or diffusely that were immunoreactive for cytokeratin. Immunoreactivity for cytokeratin was also noted for hyperplastic bronchiolar neuroepithelial bodies. Cellular hyperplasias extending out into the alveolar parenchyma contained ciliated cells and frequently consisted of cells immunoreactive for CCA, showing them to be of bronchiolar Clara cell origin. Tumors developed from bronchiolar cell hyperplasias localized within bronchioles and from bronchiolar cells lining former alveolar walls. Neoplastic growth patterns were tubulo-papillary, forming loose networks or densely cellular areas. Immunoreactivity for cytoplasmic CCA was found in 50% of the tumors and was seen most frequently in small cuboidal cells and larger, vacuolated cells scattered throughout the neoplasms. In summary, evidence is presented that NDEA-induced pulmonary tumors of the Syrian golden hamster originated from cells lining bronchioles and from extrabronchiolar Clara cell hyperplasias of the terminal bronchioles. As the

  7. Olfactory and solitary chemosensory cells: two different chemosensory systems in the nasal cavity of the American alligator, Alligator mississippiensis

    Directory of Open Access Journals (Sweden)

    Hansen Anne

    2007-08-01

    Full Text Available Abstract Background The nasal cavity of all vertebrates houses multiple chemosensors, either innervated by the Ist (olfactory or the Vth (trigeminal cranial nerve. Various types of receptor cells are present, either segregated in different compartments (e.g. in rodents or mingled in one epithelium (e.g. fish. In addition, solitary chemosensory cells have been reported for several species. Alligators which seek their prey both above and under water have only one nasal compartment. Information about their olfactory epithelium is limited. Since alligators seem to detect both volatile and water-soluble odour cues, I tested whether different sensory cell types are present in the olfactory epithelium. Results Electron microscopy and immunocytochemistry were used to examine the sensory epithelium of the nasal cavity of the American alligator. Almost the entire nasal cavity is lined with olfactory (sensory epithelium. Two types of olfactory sensory neurons are present. Both types bear cilia as well as microvilli at their apical endings and express the typical markers for olfactory neurons. The density of these olfactory neurons varies along the nasal cavity. In addition, solitary chemosensory cells innervated by trigeminal nerve fibres, are intermingled with olfactory sensory neurons. Solitary chemosensory cells express components of the PLC-transduction cascade found in solitary chemosensory cells in rodents. Conclusion The nasal cavity of the American alligator contains two different chemosensory systems incorporated in the same sensory epithelium: the olfactory system proper and solitary chemosensory cells. The olfactory system contains two morphological distinct types of ciliated olfactory receptor neurons.

  8. Quantitative analysis of crypt cell population during postnatal development of the olfactory organ of the guppy, Poecilia reticulata (Teleostei, Poecilidae), from birth to sexual maturity.

    Science.gov (United States)

    Bettini, Simone; Lazzari, Maurizio; Franceschini, Valeria

    2012-08-01

    Crypt cells are one of three types of olfactory sensory neuron, differing from ciliated and microvillar cells in shape, localization and number, and found only in fish. Although crypt cells are morphologically well characterized, their function remains unclear. They were hypothesized to be involved in reproductive behaviours by detecting sex pheromones, but electrophysiological investigations revealed sensitivity to only amino acids. However, the number of crypt cells in adult guppies is not the same in the two sexes. In this study, we compared the size of the crypt cell population in juvenile guppies during the first 90 days after birth. The purpose of our study was to clarify whether a correlation exists between sex and the number of these olfactory neurons. The data show that guppies reach adult crypt cell density when they become sexually mature. Despite a constant increment in volume during development of the olfactory organ, the minimum density of crypt neurons occurs at ~45 days. Moreover, in the early weeks, the density of crypt neurons is greater in males than in females because in females the total number of cells decreases significantly after just 7 days. In adults, however, crypt neurons are found in higher density in females than in males. These findings suggest that the number of crypt cells is sex specific, with independent developmental dynamics between males and females. A role in pheromone detection could explain such a difference, but the early appearance of crypt cells in the first days of life is suggestive of other, not sexually related, functions.

  9. Efeito da monensina e do óleo de soja sobre os protozoários ciliados do rúmen e correlação dos protozoários com parâmetros da fermentação ruminal e digestivos Effect of monensin and soybean oil on rumen ciliate protozoa and correlation between protozoa with ruminal fermentation and digestive parameters

    Directory of Open Access Journals (Sweden)

    Isabel Martinele

    2008-06-01

    lactating cows on the counting of ciliate protozoa beyond establishing correlations between number of protozoa with some parameters of digestion and ruminal fermentation. The treatments consisted of the inclusion of 33 ppm of sodium monensin or soybean oil at 4% DM, as following: control diet, without oil or monensin - CT; diet with monensin - MN; diet with soybean oil - OL; diet with the combination of 33 ppm of monensin and 4% of soybean oil - OM. Occurrence of 11 ciliate genera was observed, being Entodinium the predominant in all treatments. No significant soybean oil × monensin interaction was observed on protozoa number and genera. The genera Entodinium, Dasytricha, Eremoplastron and Isotricha reduced in the diets with oil, while monensin reduced the counting of Dasytricha, Eremoplastron and Epidinium. The total number of ciliate protozoa and cellulolytics protozoa was reduced by soybean oil and monensin effects, showing a defaunatory additive effect when combined the oil and the monensin. The ciliate cellulolytics was reduced by linoleic acid intake and was related positively with NDF ruminal digestibility and ruminal ammonia. The total number of protozoa was correlated with the molar proportion of propionate in the ruminal liquid, suggesting that monensin and soybean oil, due their defaunatory effect, can reduce the loss of methane in the rumen.

  10. Culturing of Human Nasal Epithelial Cells at the Air Liquid Interface

    Science.gov (United States)

    Müller, Loretta; Brighton, Luisa E.; Carson, Johnny L.; Fischer, William A.; Jaspers, Ilona

    2013-01-01

    In vitro models using human primary epithelial cells are essential in understanding key functions of the respiratory epithelium in the context of microbial infections or inhaled agents. Direct comparisons of cells obtained from diseased populations allow us to characterize different phenotypes and dissect the underlying mechanisms mediating changes in epithelial cell function. Culturing epithelial cells from the human tracheobronchial region has been well documented, but is limited by the availability of human lung tissue or invasiveness associated with obtaining the bronchial brushes biopsies. Nasal epithelial cells are obtained through much less invasive superficial nasal scrape biopsies and subjects can be biopsied multiple times with no significant side effects. Additionally, the nose is the entry point to the respiratory system and therefore one of the first sites to be exposed to any kind of air-borne stressor, such as microbial agents, pollutants, or allergens. Briefly, nasal epithelial cells obtained from human volunteers are expanded on coated tissue culture plates, and then transferred onto cell culture inserts. Upon reaching confluency, cells continue to be cultured at the air-liquid interface (ALI), for several weeks, which creates more physiologically relevant conditions. The ALI culture condition uses defined media leading to a differentiated epithelium that exhibits morphological and functional characteristics similar to the human nasal epithelium, with both ciliated and mucus producing cells. Tissue culture inserts with differentiated nasal epithelial cells can be manipulated in a variety of ways depending on the research questions (treatment with pharmacological agents, transduction with lentiviral vectors, exposure to gases, or infection with microbial agents) and analyzed for numerous different endpoints ranging from cellular and molecular pathways, functional changes, morphology, etc. In vitro models of differentiated human nasal epithelial

  11. Culturing of human nasal epithelial cells at the air liquid interface.

    Science.gov (United States)

    Müller, Loretta; Brighton, Luisa E; Carson, Johnny L; Fischer, William A; Jaspers, Ilona

    2013-10-08

    In vitro models using human primary epithelial cells are essential in understanding key functions of the respiratory epithelium in the context of microbial infections or inhaled agents. Direct comparisons of cells obtained from diseased populations allow us to characterize different phenotypes and dissect the underlying mechanisms mediating changes in epithelial cell function. Culturing epithelial cells from the human tracheobronchial region has been well documented, but is limited by the availability of human lung tissue or invasiveness associated with obtaining the bronchial brushes biopsies. Nasal epithelial cells are obtained through much less invasive superficial nasal scrape biopsies and subjects can be biopsied multiple times with no significant side effects. Additionally, the nose is the entry point to the respiratory system and therefore one of the first sites to be exposed to any kind of air-borne stressor, such as microbial agents, pollutants, or allergens. Briefly, nasal epithelial cells obtained from human volunteers are expanded on coated tissue culture plates, and then transferred onto cell culture inserts. Upon reaching confluency, cells continue to be cultured at the air-liquid interface (ALI), for several weeks, which creates more physiologically relevant conditions. The ALI culture condition uses defined media leading to a differentiated epithelium that exhibits morphological and functional characteristics similar to the human nasal epithelium, with both ciliated and mucus producing cells. Tissue culture inserts with differentiated nasal epithelial cells can be manipulated in a variety of ways depending on the research questions (treatment with pharmacological agents, transduction with lentiviral vectors, exposure to gases, or infection with microbial agents) and analyzed for numerous different endpoints ranging from cellular and molecular pathways, functional changes, morphology, etc. In vitro models of differentiated human nasal epithelial

  12. Ependyma of the central canal of the rat spinal cord: a light and transmission electron microscopic study.

    Science.gov (United States)

    Bruni, J E; Reddy, K

    1987-06-01

    Ependymal cells of the rat central canal were examined with a view to identifying features that distinguish them regionally and from their counterparts elsewhere in the ventricular system. The results revealed that the lining consisted for the most part of a pseudostratified layer of uniformly organised cuboidal to columnar ependymal cells present in largest numbers in lumbar and sacral segments and in the conus. Two cell variants were identified on the basis of the presence or absence of a radially directed cytoplasmic process originating from the base of the cell. The tanycytic form of ependymal cell was encountered along the entire length of the central canal but with increased frequency in caudalmost segments. Ependymal cells were largely similar in ultrastructural appearance along the length of the cord. Although they were also similar in appearance and orientation to their counterparts in the ventricles they did exhibit some unique features. The most notable were the prominent junctional complexes and associated filaments present along the lateral border of the cells near their apex and the abundance of intermediate filaments in tanycytes. The central canal of the filum differed most markedly from other segments of the cord and resembled in structure the primitive ependymal tube of the caudal cord in lower vertebrates. Ependymal cells of the cord were not sufficiently dissimilar morphologically from their counterparts in the ventricles to account for differences in proliferative capacity in response to localised injury. A factor that merits further study is the difference in numbers of tanycyte ependymal cells in the two locations for they may be the reactive elements that proliferate in response to injury.

  13. Meningeal cells and glia establish a permissive environment for axon regeneration after spinal cord injury in newts

    Directory of Open Access Journals (Sweden)

    Odelberg Shannon J

    2011-01-01

    Full Text Available Abstract Background Newts have the remarkable ability to regenerate their spinal cords as adults. Their spinal cords regenerate with the regenerating tail after tail amputation, as well as after a gap-inducing spinal cord injury (SCI, such as a complete transection. While most studies on newt spinal cord regeneration have focused on events occurring after tail amputation, less attention has been given to events occurring after an SCI, a context that is more relevant to human SCI. Our goal was to use modern labeling and imaging techniques to observe axons regenerating across a complete transection injury and determine how cells and the extracellular matrix in the injury site might contribute to the regenerative process. Results We identify stages of axon regeneration following a spinal cord transection and find that axon regrowth across the lesion appears to be enabled, in part, because meningeal cells and glia form a permissive environment for axon regeneration. Meningeal and endothelial cells regenerate into the lesion first and are associated with a loose extracellular matrix that allows axon growth cone migration. This matrix, paradoxically, consists of both permissive and inhibitory proteins. Axons grow into the injury site next and are closely associated with meningeal cells and glial processes extending from cell bodies surrounding the central canal. Later, ependymal tubes lined with glia extend into the lesion as well. Finally, the meningeal cells, axons, and glia move as a unit to close the gap in the spinal cord. After crossing the injury site, axons travel through white matter to reach synaptic targets, and though ascending axons regenerate, sensory axons do not appear to be among them. This entire regenerative process occurs even in the presence of an inflammatory response. Conclusions These data reveal, in detail, the cellular and extracellular events that occur during newt spinal cord regeneration after a transection injury and

  14. Matrix metalloproteinase production in regenerating axolotl spinal cord.

    Science.gov (United States)

    Chernoff, E A; O'Hara, C M; Bauerle, D; Bowling, M

    2000-01-01

    In urodele amphibian spinal cord regeneration, the ependymal cells lining the central canal remodel the lesion site to favor axonal regrowth. We profiled the production of matrix metalloproteinases by injury-reactive mesenchymal ependymal cells in vivo and in vitro and found that matrix metalloproteinases are involved in this remodeling process in the axolotl (Ambystoma mexicanum). The production of cell-associated matrix metalloproteinases in vivo was shown to be identical to that in our cultured ependymal cell model system. Activated and zymogen forms of matrix metalloproteinases were identified using zymography, chemical inhibitors of matrix metalloproteinases, and cleavage of propeptides by organomercurials. The principal cellular proteinases consisted of matrix metalloproteinase-2 (gelatinase A) and matrix metalloproteinase-1 (type I collagenase), which display characteristic shifts in molecular weight following proenzyme processing by organomercurials. In addition, ependymal cell conditioned medium contained secreted forms of the enzyme undetectable in situ. Matrix metalloproteinase-9 (gelatinase B) as well as matrix metalloproteinase-2 and matrix metalloproteinase-1 were secreted and casein substrate zymography showed the presence of a small amount of a very high molecular weight matrix metalloproteinase-3 (prostromelysin) secreted into the culture medium. Matrix metalloproteinases were still present at 4 weeks post-lesioning when the ependymal cells have just re-epithelialized, but decreased near the completion of regeneration (8 weeks post-lesioning). Zymography showed no detectable matrix metalloproteinases in unlesioned cord but the presence of tissue inhibitor of metalloproteinase-1 in intact cord was seen by Western blotting. This study shows that matrix metalloproteinases are associated with urodele spinal cord regeneration and validates the use of our ependymal cell tissue culture model system to evaluate ependymal cell behavior during spinal cord

  15. Symbiotic Chlorella variabilis incubated under constant dark conditions for 24 hours loses the ability to avoid digestion by host lysosomal enzymes in digestive vacuoles of host ciliate Paramecium bursaria.

    Science.gov (United States)

    Kodama, Yuuki; Fujishima, Masahiro

    2014-12-01

    Endosymbiosis between symbiotic Chlorella and alga-free Paramecium bursaria cells can be induced by mixing them. To establish the endosymbiosis, algae must acquire temporary resistance to the host lysosomal enzymes in the digestive vacuoles (DVs). When symbiotic algae isolated from the alga-bearing paramecia are kept under a constant dark conditions for 24 h before mixing with the alga-free paramecia, almost all algae are digested in the host DVs. To examine the cause of algal acquisition to the host lysosomal enzymes, the isolated algae were kept under a constant light conditions with or without a photosynthesis inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea for 24 h, and were mixed with alga-free paramecia. Unexpectedly, most of the algae were not digested in the DVs irrespective of the presence of the inhibitor. Addition of 1 mM maltose, a main photosynthetic product of the symbiotic algae or of a supernatant of the isolated algae kept for 24 h under a constant light conditions, did not rescue the algal digestion in the DVs. These observations reveal that unknown factors induced by light are a prerequisite for algal resistance to the host lysosomal enzymes.

  16. Effect of valproic acid on endogenous neural stem cell proliferation in a rat model of spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Guoxin Nan; Ming Li; Weihong Liao; Jiaqiang Qin; Yujiang Cao; Youqiong Lu

    2009-01-01

    BACKGROUND: Valproic acid has been reported to decrease apoptosis, promote neuronal differentiation of brain-derived neural stem cells, and inhibit glial differentiation of brain-derived neural stem cells.OBJECTIVE: To investigate the effects of valproic acid on proliferation of endogenous neural sterm cells in a rat model of spinal cord injury.DESIGN, TIME AND SETTING: A randomized, controlled, neuropathological study was performed at Key Laboratory of Trauma, Buming, and Combined Injury, Research Institute of Surgery, Daping Hospital, the Third Military Medical University of Chinese PLA between November 2005 and February 2007.MATERIALS: A total of 45 adult, Wistar rats were randomly divided into sham surgery (n=5), injury(n=20), and valproic acid (n=20) groups. Valproic acid was provided by Sigma, USA.METHODS: Injury was induced to the T10 segment in the injury and valproic acid groups using the metal weight-dropping method. The spinal cord was exposed without contusion in the sham surgery group. Rats in the valproic acid group were intraperitoneally injected with 150 mg/kg valproic acid every 12 hours (twice in total).MAIN OUTCOME MEASURES: Nestin expression (5 mm from injured center) was detected using immunohistochemistry at 1, 3 days, 1, 4, and 8 weeks post-injury.RESULTS: Low expression of nestin was observed in the cytoplasm, but rarely in the white matter of the spinal cord in the sham surgery group. In the injury group, nestin expression was observed in the ependyma and pia mater one day after injury, and expression reached a peak at 1 week (P<0.05).Expression was primarily observed in the ependymal cells, which expanded towards the white and gray matter of the spinal cord. Nestin expression rapidly decreased by 4 weeks post-injury, and had almost completely disappeared by 8 weeks. At 24 hours after spinal cord injury, there was nosignificant difference in nestin expression between the valproic acid and injury groups. At 1 week,there was a significant

  17. The small GTPase Rab8 interacts with VAMP-3 to regulate the delivery of recycling T-cell receptors to the immune synapse.

    Science.gov (United States)

    Finetti, Francesca; Patrussi, Laura; Galgano, Donatella; Cassioli, Chiara; Perinetti, Giuseppe; Pazour, Gregory J; Baldari, Cosima T

    2015-07-15

    IFT20, a component of the intraflagellar transport (IFT) system that controls ciliogenesis, regulates immune synapse assembly in the non-ciliated T-cell by promoting T-cell receptor (TCR) recycling. Here, we have addressed the role of Rab8 (for which there are two isoforms Rab8a and Rab8b), a small GTPase implicated in ciliogenesis, in TCR traffic to the immune synapse. We show that Rab8, which colocalizes with IFT20 in Rab11(+) endosomes, is required for TCR recycling. Interestingly, as opposed to in IFT20-deficient T-cells, TCR(+) endosomes polarized normally beneath the immune synapse membrane in the presence of dominant-negative Rab8, but were unable to undergo the final docking or fusion step. This could be accounted for by the inability of the vesicular (v)-SNARE VAMP-3 to cluster at the immune synapse in the absence of functional Rab8, which is responsible for its recruitment. Of note, and similar to in T-cells, VAMP-3 interacts with Rab8 at the base of the cilium in NIH-3T3 cells, where it regulates ciliary growth and targeting of the protein smoothened. The results identify Rab8 as a new player in vesicular traffic to the immune synapse and provide insight into the pathways co-opted by different cell types for immune synapse assembly and ciliogenesis.

  18. Unicellular eukaryotes as models in cell and molecular biology: critical appraisal of their past and future value.

    Science.gov (United States)

    Simon, Martin; Plattner, Helmut

    2014-01-01

    Unicellular eukaryotes have been appreciated as model systems for the analysis of crucial questions in cell and molecular biology. This includes Dictyostelium (chemotaxis, amoeboid movement, phagocytosis), Tetrahymena (telomere structure, telomerase function), Paramecium (variant surface antigens, exocytosis, phagocytosis cycle) or both ciliates (ciliary beat regulation, surface pattern formation), Chlamydomonas (flagellar biogenesis and beat), and yeast (S. cerevisiae) for innumerable aspects. Nowadays many problems may be tackled with "higher" eukaryotic/metazoan cells for which full genomic information as well as domain databases, etc., were available long before protozoa. Established molecular tools, commercial antibodies, and established pharmacology are additional advantages available for higher eukaryotic cells. Moreover, an increasing number of inherited genetic disturbances in humans have become elucidated and can serve as new models. Among lower eukaryotes, yeast will remain a standard model because of its peculiarities, including its reduced genome and availability in the haploid form. But do protists still have a future as models? This touches not only the basic understanding of biology but also practical aspects of research, such as fund raising. As we try to scrutinize, due to specific advantages some protozoa should and will remain favorable models for analyzing novel genes or specific aspects of cell structure and function. Outstanding examples are epigenetic phenomena-a field of rising interest.

  19. A survey of polymerase chain reaction (PCR) amplification studies of unicellular protists using single-cell PCR.

    Science.gov (United States)

    Lynn, Denis H; Pinheiro, Marcel

    2009-01-01

    We surveyed a variety of studies that have used single-cell polymerase chain reaction (SC-PCR) to examine the gene sequences of a diversity of unicellular protists. Representatives of all the Super-Groups of eukaryotes have been subjected to SC-PCR with ciliates and dinoflagellates being most commonly examined. The SC-PCR was carried out either by directly amplifying a single lysed cell or by first extracting DNA and following this with amplification of the DNA extract. Cell lysis methods included heating, freezing, mechanical rupture, and enzyme digestion. Cells fixed or preserved with ethanol, methanol, and Lugol's have also been used successfully. Heminested or seminested PCR might follow the initial PCR, whose products were then directly sequenced or cloned and then sequenced. The methods are not complicated. This should encourage protistologists to use SC-PCR in the description of new or revised taxa, especially rare and unculturable forms, and it should also enable the probing of gene expression in relation to life history stages.

  20. Mouse bronchiolar cell carcinogenesis. Histologic characterization and expression of Clara cell antigen in lesions induced by N-nitrosobis-(2-chloroethyl) ureas.

    Science.gov (United States)

    Rehm, S.; Lijinsky, W.; Singh, G.; Katyal, S. L.

    1991-01-01

    Female Swiss mice (Cr:NIH(S)) developed bronchiolar cell hyperplasia, dysplasia, metaplasia, and various morphologic types of bronchiolar cell tumors after topical (skin) application of N-nitroso-methyl-bis-chloroethylurea (NMBCU) or N-nitroso-tris-chloroethylurea (NTCU). These compounds are the first found to induce systemically bronchiolar cell tumors in mice in high incidence. Twice a week, with a 3-day interval, a 25-microliter drop of 0.04 mol/l (molar) NMBCU or NTCU in acetone was applied to the shaved interscapular integument for a maximum of 35 to 40 weeks. The earliest lung neoplasms were seen in mice that died after 23 weeks of treatment and affected 11 of 19 with NMBCU and 14 of 19 with NTCU treatment. Tumor growth pattern was nodular or the neoplastic tissue was frequently disseminated throughout the parenchyma, starting from multicentric peribronchiolar foci. The most common tumor types were squamous cell carcinomas and adenosquamous carcinomas, followed by adenocarcinomas with or without secretory cells, and a single ciliated-cell tumor. Histochemical and immunohistochemical studies were carried out on paraffin-embedded lungs using the avidin-biotin immunoperoxidase complex procedure and antisera against keratin, Clara cell antigen, surfactant apoprotein, neuron-specific enolase, bombesin, and chromogranin A. In several mice from both groups, hyperplasias and tumors were composed of cells expressing Clara cell antigen. No tumor cells were found expressing alveolar type II or neuroendocrine cell markers. It appeared that bronchiolar cells, in particular Clara cells, had migrated from terminal bronchioles or invaded bronchiolar walls to extend into the alveolar parenchyma. Squamous cell metaplasia with keratin expression was seen within airways or associated with glandular tumors, especially at the periphery. A unique cell type, with large eosinophilic globules and associated eosinophilic crystals, was seen lining airways or forming hyperplastic and

  1. New details indicated by different stainings during conjugation of ciliated protozoa Paramecium%不同染色方法揭示纤毛原生动物草履虫接合生殖过程的新细节

    Institute of Scientific and Technical Information of China (English)

    高欣; 杨仙玉; 朱嘉骏; 袁进强; 王逸雯; 宋敏国

    2011-01-01

    During conjugation of Paramecium caudatum,nuclear events occur in a scheduled program.Morphological studies on nuclear behavior during conjugation of P.caudatum have been performed since the end of the 19th century.Here we report on new details concerning the conjugation of P.caudatum through the staining of conjugating cells with protargol,carbol fuchsin solution,Hoechst 33342 and immunofluorescence labeling with monoclonal antibody of anti-α tubulin.1) The crescent nucleus is a characteristic of the meiotic prophase of P.caudatum,has an unstained area.We stained this area with protargol,which was separated from the chromatin area and was not detected by the other stainings.2) In regards to the four meiotic products,it has long been considered that only one product enters the paroral cone region (PC) and survives after meiosis.However,our protargol and immunofluorescence labeling results indicated that PC entrance of the meiotic product happened before the completion of meiosis instead of after.3) In our previous study,protargol staining indicated the presence of a swollen structure around the central part of the "U" and "V" shaped spindles connecting the two types of prospective pronuclei.However,immunofluorescence labeling with anti-α tubulin antibodies gave a different image from protargol.All these observations form the basis for further studies of their molecular mechanisms.%通过石炭酸品红、Hoechst 33342、蛋白银及免疫荧光标记等染色方法对草履虫接合生殖过程进行了重新观察,结果发现:1)新月核是第一次减数分裂前期小核的主要形态学特征,在核内有一未被石炭酸品红、Hoechst 33342着色区域,蛋白银染色则清楚显示该结构;2)4个单倍体减数分裂产物中的1个核进入口旁锥完成配前第三次核分裂,其余3核退化.蛋白银染色和抗α微管蛋白单克隆抗体进行免疫荧光标记显示,核进入口旁锥的时期在第二次减数分裂末期

  2. Morphology, innervation, and peripheral sensory cells of the siphon of aplysia californica.

    Science.gov (United States)

    Carrigan, Ian D; Croll, Roger P; Wyeth, Russell C

    2015-11-01

    The siphon of Aplysia californica has several functions, including involvement in respiration, excretion, and defensive inking. It also provides sensory input for defensive withdrawals that have been studied extensively to examine mechanisms that underlie learning. To better understand the neuronal bases of these functions, we used immunohistochemistry to catalogue peripheral cell types and innervation of the siphon in stage 12 juveniles (chosen to allow observation of tissues in whole-mounts). We found that the siphon nerve splits into three major branches, leading ultimately to a two-part FMRFamide-immunoreactive plexus and an apparently separate tyrosine hydroxylase-immunoreactive plexus. Putative sensory neurons included four distinct types of tubulin-immunoreactive bipolar cells (one likely also tyrosine hydroxylase immunoreactive) that bore ciliated dendrites penetrating the epithelium. A fifth bipolar neuron type (tubulin- and FMRFamide-immunoreactive) occurred deeper in the tissue, associated with part of the FMRFamide-immunoreactive plexus. Our observations emphasize the structural complexity of the peripheral nervous system of the siphon, and the importance of direct tests of the various components to better understand the functioning of the entire organ, including its role in defensive withdrawal responses.

  3. Control of vertebrate core planar cell polarity protein localization and dynamics by Prickle 2.

    Science.gov (United States)

    Butler, Mitchell T; Wallingford, John B

    2015-10-01

    Planar cell polarity (PCP) is a ubiquitous property of animal tissues and is essential for morphogenesis and homeostasis. In most cases, this fundamental property is governed by a deeply conserved set of 'core PCP' proteins, which includes the transmembrane proteins Van Gogh-like (Vangl) and Frizzled (Fzd), as well as the cytoplasmic effectors Prickle (Pk) and Dishevelled (Dvl). Asymmetric localization of these proteins is thought to be central to their function, and understanding the dynamics of these proteins is an important challenge in developmental biology. Among the processes that are organized by the core PCP proteins is the directional beating of cilia, such as those in the vertebrate node, airway and brain. Here, we exploit the live imaging capabilities of Xenopus to chart the progressive asymmetric localization of fluorescent reporters of Dvl1, Pk2 and Vangl1 in a planar polarized ciliated epithelium. Using this system, we also characterize the influence of Pk2 on the asymmetric dynamics of Vangl1 at the cell cortex, and we define regions of Pk2 that control its own localization and those impacting Vangl1. Finally, our data reveal a striking uncoupling of Vangl1 and Dvl1 asymmetry. This study advances our understanding of conserved PCP protein functions and also establishes a rapid, tractable platform to facilitate future in vivo studies of vertebrate PCP protein dynamics.

  4. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  5. Pathogenesis of cerebral malformations in human fetuses with meningomyelocele

    Directory of Open Access Journals (Sweden)

    Brouwer Oebele F

    2008-03-01

    Full Text Available Abstract Background Fetal spina bifida aperta (SBA is characterized by a spinal meningomyelocele (MMC and associated with cerebral pathology, such as hydrocephalus and Chiari II malformation. In various animal models, it has been suggested that a loss of ventricular lining (neuroepithelial/ependymal denudation may trigger cerebral pathology. In fetuses with MMC, little is known about neuroepithelial/ependymal denudation and the initiating pathological events. The objective of this study was to investigate whether neuroepithelial/ependymal denudation occurs in human fetuses and neonates with MMC, and if so, whether it is associated with the onset of hydrocephalus. Methods Seven fetuses and 1 neonate (16–40 week gestational age, GA with MMC and 6 fetuses with normal cerebral development (22–41 week GA were included in the study. Identification of fetal MMC and clinical surveillance of fetal head circumference and ventricular width was performed by ultrasound (US. After birth, MMC was confirmed by histology. We characterized hydrocephalus by increased head circumference in association with ventriculomegaly. The median time interval between fetal cerebral ultrasound and fixing tissue for histology was four days. Results At 16 weeks GA, we observed neuroepithelial/ependymal denudation in the aqueduct and telencephalon together with sub-cortical heterotopias in absence of hydrocephalus and/or Chiari II malformation. At 21–34 weeks GA, we observed concurrence of aqueductal neuroepithelial/ependymal denudation and progenitor cell loss with the Chiari II malformation, whereas hydrocephalus was absent. At 37–40 weeks GA, neuroepithelial/ependymal denudation coincided with Chiari II malformation and hydrocephalus. Sub-arachnoidal fibrosis at the convexity was absent in all fetuses but present in the neonate. Conclusion In fetal SBA, neuroepithelial/ependymal denudation in the telencephalon and the aqueduct can occur before Chiari II malformation

  6. Unsteady feeding and optimal strokes of model ciliates

    CERN Document Server

    Michelin, Sebastien

    2012-01-01

    The flow field created by swimming microorganisms not only enables their locomotion but also leads to advective transport of nutrients. In this paper we address analytically and computationally the link between unsteady feeding and unsteady swimming on a model microorganism, the spherical squirmer, actuating the fluid in a time-periodic manner. We start by performing asymptotic calculations at low P\\'eclet number (Pe) on the advection-diffusion problem for the nutrients. We show that the mean rate of feeding as well as its fluctuations in time depend only on the swimming modes of the squirmer up to order Pe^(3/2), even when no swimming occurs on average, while the influence of non-swimming modes comes in only at order Pe^2. We also show that generically we expect a phase delay between feeding and swimming of 1/8th of a period. Numerical computations for illustrative strokes at finite Pe confirm quantitatively our analytical results linking swimming and feeding. We finally derive, and use, an adjoint-based opt...

  7. A new peritrichous Ciliate as a symphoriont on a Tardigrade

    NARCIS (Netherlands)

    Land, van der J.

    1964-01-01

    INTRODUCTION On 24 September 1962 a number of Tardigrada was obtained from a sample of lichens from the French Alps. The lichens had been collected Figs. 1, 2. Pyxidium tardigradum n. sp. on Hypsibius oberhaeuseri (Doy.). on 27 June 1961 from a rock in the department Haute Savoie and had been preser

  8. Effects of irradiation on the peritrich ciliates Vorticella and Telotrochidium

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, W.W.

    1976-07-01

    Vorticella microstoma and Telotrochidium henneguyi were exposed to doses of x- and gamma-radiation ranging from 46 r to 120 Kr. Irradiation was applied to freshly excysted motile organisms. Doses below 2 Kr did not induce noticeable morphological effects in either peritrich. Doses between 2 and 5 Kr induced Pellicular blisters in Vorticella but to a very limited extent; the blisters were more prevalent 12 hr post-irradiation. Pellicular blisters were not induced in Telotrochidium, regardless of the dose. A 30 Kr dose caused both peritrichs to become more rounded than the control animals. Doses above 2 Kr altered the normal life cycle of both peritrichs as follows. The post-excystment binary fission stage was extended beyond the normal 18 yr. Post-excystment conjugation occurred later than the usual 18 to 36 hr period. A 38 Kr dose depressed Vorticella's population growth curve during the first 24 hr after irradiation, but recovery and growth was almost complete between 24 to 48 hr post-irradiation. A 57 Kr dose also depressed the population growth curve during the 24 hr following irradiation, but recovery to near normal did not occur until 60 hr post-irradiation. Telotrochidium's response was different and inconsistent in comparison with Vorticella's response. In some experiments only 10% of the Telotrochidium population survived a single 38 Kr dose and growth occurred. Likewise, 57 Kr gave inconsistent results in that it was lethal to the total population in some experiments but merely retarded growth and recovery of the total population in other experiments.

  9. Persistent disruption of ciliated epithelium following paediatric lung transplantation.

    Science.gov (United States)

    Thomas, Biju; Aurora, Paul; Spencer, Helen; Elliott, Martin; Rutman, Andrew; Hirst, Robert A; O'Callaghan, Christopher

    2012-11-01

    It is unclear whether ciliary function following lung transplantation is normal or not. Our aim was to study the ciliary function and ultrastructure of epithelium above and below the airway anastomosis and the peripheral airway of children following lung transplantation. We studied the ciliary beat frequency (CBF) and beat pattern, using high speed digital video imaging and ultrastructure by transmission electron microscopy, of bronchial epithelium from above and below the airway anastomosis and the peripheral airway of 10 cystic fibrosis (CF) and 10 non-suppurative lung disease (NSLD) paediatric lung transplant recipients. Compared to epithelium below the anastomosis, the epithelium above the anastomosis in the CF group showed reduced CBF (median (interquartile range): 10.5 (9.0-11.4) Hz versus 7.4 (6.4-9.2) Hz; pepithelium above the anastomosis, the epithelium below the anastomosis showed marked ultrastructural abnormalities (median duration post-transplant 7-12 months). Ciliary dysfunction is a feature of native airway epithelium in paediatric CF lung transplant recipients. The epithelium below the airway anastomosis shows profound ultrastructural abnormalities in both CF and NSLD lung transplant recipients, many months after transplantation.

  10. Nicotine modulates neurogenesis in the central canal during experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Gao, Z; Nissen, J C; Legakis, L; Tsirka, S E

    2015-06-25

    Nicotine has been shown to attenuate experimental autoimmune encephalomyelitis (EAE) through inhibiting inflammation in microglial populations during the disease course. In this study, we investigated whether nicotine modified the regenerative process in EAE by examining nestin-expressing neural stem cells (NSCs) in the spinal cord, which is the primary area of demyelination and inflammation in EAE. Our results show that the endogenous neurogenic responses in the spinal cord after EAE are limited and delayed: while nestin expression is increased, the proliferation of ependymal cells is inhibited compared to healthy animals. Nicotine application significantly reduced nestin expression and partially allowed for the proliferation of ependymal cells. We found that reduction of ependymal cell proliferation correlated with inflammation in the same area, which was relieved by the administration of nicotine. Further, increased numbers of oligodendrocytes (OLs) were observed after nicotine treatment. These findings give a new insight into the mechanism of how nicotine functions to attenuate EAE.

  11. Effect of an energy-deficient diet on populations of ciliate protozoans in bovine rumen Efeito da deficiência de energia na dieta sobre a população de protozoários ciliados do rúmen de bovinos

    Directory of Open Access Journals (Sweden)

    P.C. Soares

    2008-02-01

    Full Text Available Ten young rumen-cannulated crossbred steers were randomly divided into two groups: a control group (C; n=4, which was fed a balanced diet for daily weight gain of 900g; and a pronounced energy-deprived group (PED; n=6, receiving 30% less of the required energy for maintenance. After 140 days of these alimentary regimes, rumen fluid and urine samples were collected for biochemical and functional tests, before feeding and at 1, 3, 6, and 9 hours after feeding. The energy-deprivation diet caused a significant reduction in the number of Entodinium, Eodinium, Isotricha, Dasytricha, Eremoplastron, Eudiplodinium, Metadinium, Charonina, Ostracodinium, and Epidinium protozoa. There was no effect of the time of sampling in both groups on the total number of ciliates in rumen fluid. A higher number of protozoan forms in binary division were recorded in the control group, at the 6th and 9th hours after feeding (PForam utilizados 10 novilhos mestiços com cânula ruminal, distribuídos em dois grupos: no grupo controle (C; n=4 receberam dieta balanceada para ganho diário de 900g; no grupo tratado com carência pronunciada de energia (CP; n=6, receberam dieta com 30% a menos do nível de mantença em energia. Após 140 dias sob esses regimes de alimentação, foram coletadas amostras do fluido ruminal e urina, para realização de provas bioquímicas e funcionais, antes e às 1, 3, 6 e 9 horas após o fornecimento do alimento. A carência energética resultou em diminuição significativa na quantidade dos protozoários Entodinium, Eodinium, Isotricha, Dasytricha, Eremoplastron, Eudiplodinium, Metadinium, Charonina, Ostracodinium e Epidinium. Não houve efeito da hora de coleta sobre o total de ciliados nos grupos C e CP. Maior número de formas em divisão binária foi registrado no grupo C, na sexta e nona horas pós-alimentação (P<0,019. Observaram-se altas correlações positivas entre a contagem total de protozoários e a fermentação de glicose, am

  12. Deformation of a micro-torque swimmer

    OpenAIRE

    Ishikawa, Takuji; Tanaka, Tomoyuki; Imai, Yohsuke; Omori, Toshihiro; Matsunaga, Daiki

    2016-01-01

    The membrane tension of some kinds of ciliates has been suggested to regulate upward and downward swimming velocities under gravity. Despite its biological importance, deformation and membrane tension of a ciliate have not been clarified fully. In this study, we numerically investigated the deformation of a ciliate swimming freely in a fluid otherwise at rest. The cell body was modelled as a capsule with a hyperelastic membrane enclosing a Newtonian fluid. Thrust forces due to the ciliary bea...

  13. Mycoplasma ovipneumoniae induces inflammatory response in sheep airway epithelial cells via a MyD88-dependent TLR signaling pathway.

    Science.gov (United States)

    Xue, Di; Ma, Yan; Li, Min; Li, Yanan; Luo, Haixia; Liu, Xiaoming; Wang, Yujiong

    2015-01-15

    Mycoplasma ovipneumoniae (M. ovipneumoniae) is a bacterium that specifically infects sheep and goat and causes ovine infectious pleuropneumonia. In an effort to understand the pathogen-host interaction between the M. ovipneumoniae and airway epithelial cells, we investigated the host inflammatory response using a primary air-liquid interface (ALI) epithelial culture model generated from bronchial epithelial cells of Ningxia Tan sheep (Ovis aries). The ALI culture of sheep bronchial epithelial cells showed a fully differentiated epithelium comprising distinct epithelial types, including the basal, ciliated and goblet cells. Exposure of ALI cultures to M. ovipneumoniae led to increased expression of Toll-like receptors (TLRs), and components of the myeloid differentiation factor 88 (MyD88)-dependent TLR signaling pathway, including the MyD88, TNF receptor-associated factor 6 (TRAF6), IL-1 receptor-associated kinases (IRAKs) and nuclear factor-kappa B (NF-κB), as well as subsequent pro-inflammatory cytokines in the epithelial cells. Of interest, infection with M. ovipneumoniae failed to induce the expression of TANK-binding kinase 1 (TBK1), TRAF3 and interferon regulatory factor 3 (IRF3), key components of the MyD88-independent signaling pathway. These results suggest that the MyD88-dependent TLR pathway may play a crucial role in sheep airway epithelial cells in response to M. ovipneumoniae infection, which also indicate that the ALI culture system may be a reliable model for investigating pathogen-host interactions between M. ovipneumoniae and airway epithelial cells.

  14. The luminal surface of thyroid cysts in SEM

    DEFF Research Database (Denmark)

    Zelander, T; Kirkeby, S

    1978-01-01

    Four of the five kinds of cells constituting the walls of thyroid cysts can be identified in the SEM. These are cuboidal cells, mucous cells, cells with large granules and ciliated cells. A correlation between SEM and TEM observations is attempted.......Four of the five kinds of cells constituting the walls of thyroid cysts can be identified in the SEM. These are cuboidal cells, mucous cells, cells with large granules and ciliated cells. A correlation between SEM and TEM observations is attempted....

  15. Comparison of the marker effects of two different fluorescent dyes in labeling endogenous neural stem cells in the central nervous system%两种荧光标记物对中枢神经系统内源性神经干细胞的标记效果比较

    Institute of Scientific and Technical Information of China (English)

    谭波涛; 虞璟; 刘媛; 伍亚民; 龙在云; 贾功伟; 虞乐华

    2012-01-01

    into the lateral ventricle of rats of DIL group or DAPI group, while DMSO or PBS 10μ1 was introduced into that of DMSO group or PBS group. Neurological severity score (NSS) was determined 2 hours and 24 hours respectively after the operation. Rats were sacrificed at day 1, 3, 7 after the injection. Serial coronal sections of the brain and spinal cord were carried out on a cryostat, and then they were observed under a confocal microscope. The fluorescence intensity of the targeted area, which highlighted by labeled ependymal cells, in the brain and spinal cord of cervical vertebrae, thoracic vertebrae and lumbar vertebrae were semi-quantified. Fluorescence intensity of each section was measured in triplicate, and a mean value was obtained. Statistical analysis was performed on 3 data sets, randomly selected from sections of brain and spinal cord obtained at day 1, 3, 7. Results Two hours after DIL injection, the rats showed no evident neurological defect. NSS value was very low, and there was no significant difference compared with the DMSO group (P>0.05). Twenty-four hours later, normal neurological function recovered in all the rats. Red fluorescence could be seen in the cytoplasm of ependymal cells in the lateral ventricle and each spinal cord segment at day 1 after the DIL injection, and it did not disappear until the 7th day. Nuclei of DAPI-labeled lateral ventricle cells were blue, with clear nuclear morphology. Choroid plexus cells of the ventricle were also labeled. However, there was no blue fluorescence in the medulla oblongata or any segment of the spinal cord. The picture at day 3 and day 7 was similar to that of day 1. No significant difference was found between fluorescence intensity in DIL or DAPI stained cells(P>0.05) at any time point. Conclusions DIL may serve as a marker of the cytoplasm of ependymal cells in the brain ventricle and spinal central canal. DAPI, which is often used in the nuclear staining, can label the ENSCs in the brain ventricle

  16. Identification and characterization of L985P, a CD20 related family member over-expressed in small cell lung carcinoma.

    Science.gov (United States)

    Bangur, Chaitanya S; Johnson, Jeffrey C; Switzer, Ann; Wang, Yi-Hong; Hill, Beth; Fanger, Gary R; Wang, Tongtong; Retter, Marc W

    2004-12-01

    We recently reported on the use of cDNA subtraction combined with microarray based expression analysis for identifying genes that are differentially over-expressed in small cell lung carcinoma. One of the several hundred genes identified using this approach was termed L985P and its molecular characterization is described in this report. The differential over-expression of L985P mRNA in SCLC, as determined by microarray analysis, was confirmed by real-time RT-PCR and Northern blot analysis. Immunohistochemical analyses show that L985P protein is highly expressed in SCLC with very restricted expression observed in normal lung, which was confined to the apical region of the ciliated bronchiolar epithelium. Flow cytometric and immunohistochemical analysis showed that L985P was localized to the cell surface. Sequence homology comparison indicated that L985P is identical to MS4A8B, a member of the recently described membrane-spanning 4-domain family, subfamily A (MS4A) gene family. The MS4A gene family currently consists of greater than 20 distinct human and mouse proteins that include CD20 and FcepsilonRIbeta. Both CD20 and FcepsilonRIbeta are involved in signaling events that regulate diverse cellular functions including cell growth regulation and differentiation. Collectively, the results presented herein demonstrate that L985P is differentially over-expressed in SCLC and may have potential clinical utility as an immunotherapeutic target for the treatment of SCLC.

  17. Culture of primary ciliary dyskinesia epithelial cells at air-liquid interface can alter ciliary phenotype but remains a robust and informative diagnostic aid.

    Directory of Open Access Journals (Sweden)

    Robert A Hirst

    Full Text Available BACKGROUND: The diagnosis of primary ciliary dyskinesia (PCD requires the analysis of ciliary function and ultrastructure. Diagnosis can be complicated by secondary effects on cilia such as damage during sampling, local inflammation or recent infection. To differentiate primary from secondary abnormalities, re-analysis of cilia following culture and re-differentiation of epithelial cells at an air-liquid interface (ALI aids the diagnosis of PCD. However changes in ciliary beat pattern of cilia following epithelial cell culture has previously been described, which has brought the robustness of this method into question. This is the first systematic study to evaluate ALI culture as an aid to diagnosis of PCD in the light of these concerns. METHODS: We retrospectively studied changes associated with ALI-culture in 158 subjects referred for diagnostic testing at two PCD centres. Ciliated nasal epithelium (PCD n = 54; non-PCD n  111 was analysed by high-speed digital video microscopy and transmission electron microscopy before and after culture. RESULTS: Ciliary function was abnormal before and after culture in all subjects with PCD; 21 PCD subjects had a combination of static and uncoordinated twitching cilia, which became completely static following culture, a further 9 demonstrated a decreased ciliary beat frequency after culture. In subjects without PCD, secondary ciliary dyskinesia was reduced. CONCLUSIONS: The change to ciliary phenotype in PCD samples following cell culture does not affect the diagnosis, and in certain cases can assist the ability to identify PCD cilia.

  18. Tetrahymena pyriformis cells are deficient in all mannose-P-dolichol-dependent mannosyltransferases but not in mannose-P-dolichol synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Yagodnik, C.; de la Canal, L.; Parodi, A.J.

    1987-09-08

    Cells of the ciliated protozoan Tetrahymena pyriformis incubated with (/sup 14/C)glucose were found to synthesize Man-P-dolichol and Glc-P-dolichol, as well as Glc/sub 3/Man/sub 5/GlcNAc/sub 2/-P-P-dolichol, the latter being the main and largest lipid derivative formed. The missing mannose residues were those known to be transferred from Man-P-dolichol in other systems. Formation of Man-P-dolichol and of dolichol-P-P-oligosaccharides containing up to five mannose units was detected in cell-free assays containing protozoan membranes, rat liver dolichol-P, unlabeled Man/sub 4-9/GlcNAc/sub 2/-P-P-dolichol from pig liver, and GDP-(/sup 14/C)Man. Under exactly the same conditions but with UDP-(/sup 14/C)Glc instead of GDP-(/sup 14/C)Man, Glc-P-dolichol and dolichol-P-P-oligosaccharides containing five mannose and one to three glucose residues were formed in the absence of the pig liver compounds. In the presence of the latter, dolichol-P-P derivatives containing nine mannose and one to three glucose units were also synthesized. It is concluded that T. pyriformis cells are deficient in all Man-P-dolichol-dependent mannosyltransferases but not in Man-P-dolichol synthesis. The role of the latter compound in this microorganism is unknown.

  19. Dendritic Cell

    OpenAIRE

    Sevda Söker

    2005-01-01

    Dendritic cells, a member of family of antigen presenting cells, are most effective cells in the primary immune response. Dendritic cells originated from dendron, in mean of tree in the Greek, because of their long and elaborate cytoplasmic branching processes. Dendritic cells constitute approximately 0.1 to 1 percent of the blood’s mononuclear cell. Dendritic cells are widely distributed, and specialized for antigen capture and T cell stimulation. In this article, structures and functions of...

  20. Repeated whole cigarette smoke exposure alters cell differentiation and augments secretion of inflammatory mediators in air-liquid interface three-dimensional co-culture model of human bronchial tissue.

    Science.gov (United States)

    Ishikawa, Shinkichi; Ito, Shigeaki

    2017-02-01

    In vitro models of human bronchial epithelium are useful for toxicological testing because of their resemblance to in vivo tissue. We constructed a model of human bronchial tissue which has a fibroblast layer embedded in a collagen matrix directly below a fully-differentiated epithelial cell layer. The model was applied to whole cigarette smoke (CS) exposure repeatedly from an air-liquid interf