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Sample records for epithelium modifications intracellulaires

  1. Epithelium

    MedlinePlus

    The term "epithelium" refers to layers of cells that line hollow organs and glands. It is also those cells that make up the outer surface of the body. Epithelial cells help to protect or enclose organs. Most produce mucus or other secretions. Certain ...

  2. Syndrome of selective IgM deficiency with severe T cell deficiency associated with disseminated cutaneous mycobacterium avium intracellulaire infection

    PubMed Central

    Gharib, Asal; Louis, Ankmalika Gupta; Agrawal, Sudhanshu; Gupta, Sudhir

    2015-01-01

    Cutaneous non-disseminated, non-tuberculous mycobacterial infections have been reported in both immunocompetent and immunocompromised subjects. Systemic Mycobacterium avium intracellulaire (MAI) have been reported in non-HIV patients with Idiopathic CD4 lymphocytopenia. We report a comprehensive immunological analysis in syndrome of selective IgM deficiency and T lymphocytopenia (both CD4+ and CD8+) with disseminated cutaneous MAI infection. Naïve (TN) and Central memory (TCM) subsets of both CD4+ and CD8+ T cells were decreased, whereas terminally differentiated effector memory (TEMRA) subset of CD4+ and CD8+ T cells were markedly increased. IFN-γ producing T cells were markedly decreased. Although CD14highCD16- proinflammatory monocytes were modestly increased, IFN-γR+ monocytes were markedly decreased. The expression of TLR3, TLR5, TLR7, and TLR9 on monocytes was decreased. Germinal center B cells (CD19+IgD-CD38+CD27lo) and B1 cells (CD20+CD27+CD43+CD70-) were markedly decreased. A role of immune alterations, including B cells and antibodies in disseminated cutaneous MAI infection is discussed. PMID:26550546

  3. Surface modification of electrospun poly(methyl methacrylate) (PMMA) nanofibers for the development of in vitro respiratory epithelium model.

    PubMed

    Rabiatul, A R; Lokanathan, Y; Rohaina, C M; Chowdhury, S R; Aminuddin, B S; Ruszymah, B H I

    2015-01-01

    Scaffold design is an important aspect of in vitro model development. In this study, nanoscaffold surface modification, namely UV radiation and genipin cross-linking to immobilize collagen on the surface of electrospun poly (methyl methacrylate) (PMMA) nanofiber sheet was investigated. Samples were divided into four groups; PMMA nanofibers (PMMA), collagen-coated PMMA nanofibers (PMMACOL), genipin cross-linked collagen-coated PMMA nanofibers (PMMAGEN), and UV-irradiated collagen-coated PMMA nanofibers (PMMAUV). 6 h of UV radiation significantly reduced the hydrophobicity of PMMA nanofibers from (131.88° ± 1.33°) to (110.04° ± 0.27°) (p < 0.05). The amount of collagen immobilized was significantly higher in PMMAGEN group (239.36 ± 16.63 μg collagen/mg nanofibers) (p < 0.05) compared to the other groups. RECs on all scaffold expressed epithelial cell-specific markers (CK18 and CK14), mucin-producing cell marker (MUC5Ac) and were actively proliferating, based on the positive expression of Ki67. Total number of attached cells was significantly the highest in PMMAUV group on day 9 (6.44 × 10(4) ± 2.77 × 10(4) cells/cm(2)) and it has the highest proliferation rate from day 4 to 9 (0.005 ± 0.003 h(-1)) compared to the other groups. Even though PMMAGEN group showed the highest collagen adsorption, in terms of cells attachment and proliferation, PMMAUV group showed a better outcome compared to the other groups. Thus, PMMAUV scaffold is more suitable to be used in the construction of in vitro respiratory epithelial model. PMID:26335265

  4. Surface modification of electrospun poly(methyl methacrylate) (PMMA) nanofibers for the development of in vitro respiratory epithelium model.

    PubMed

    Rabiatul, A R; Lokanathan, Y; Rohaina, C M; Chowdhury, S R; Aminuddin, B S; Ruszymah, B H I

    2015-01-01

    Scaffold design is an important aspect of in vitro model development. In this study, nanoscaffold surface modification, namely UV radiation and genipin cross-linking to immobilize collagen on the surface of electrospun poly (methyl methacrylate) (PMMA) nanofiber sheet was investigated. Samples were divided into four groups; PMMA nanofibers (PMMA), collagen-coated PMMA nanofibers (PMMACOL), genipin cross-linked collagen-coated PMMA nanofibers (PMMAGEN), and UV-irradiated collagen-coated PMMA nanofibers (PMMAUV). 6 h of UV radiation significantly reduced the hydrophobicity of PMMA nanofibers from (131.88° ± 1.33°) to (110.04° ± 0.27°) (p < 0.05). The amount of collagen immobilized was significantly higher in PMMAGEN group (239.36 ± 16.63 μg collagen/mg nanofibers) (p < 0.05) compared to the other groups. RECs on all scaffold expressed epithelial cell-specific markers (CK18 and CK14), mucin-producing cell marker (MUC5Ac) and were actively proliferating, based on the positive expression of Ki67. Total number of attached cells was significantly the highest in PMMAUV group on day 9 (6.44 × 10(4) ± 2.77 × 10(4) cells/cm(2)) and it has the highest proliferation rate from day 4 to 9 (0.005 ± 0.003 h(-1)) compared to the other groups. Even though PMMAGEN group showed the highest collagen adsorption, in terms of cells attachment and proliferation, PMMAUV group showed a better outcome compared to the other groups. Thus, PMMAUV scaffold is more suitable to be used in the construction of in vitro respiratory epithelial model.

  5. Progenitor Epithelium

    PubMed Central

    Marty-Santos, Leilani

    2015-01-01

    Insulin-producing β cells within the vertebrate fetal pancreas acquire their fate in a step-wise manner. Whereas the intrinsic factors dictating the transcriptional or epigenetic status of pancreatic lineages have been intensely examined, less is known about cell–cell interactions that might constitute a niche for the developing β cell lineage. It is becoming increasingly clear that understanding and recapitulating these steps may instruct in vitro differentiation of embryonic stem cells and/or therapeutic regeneration. Indeed, directed differentiation techniques have improved since transitioning from 2D to 3D cultures, suggesting that the 3D microenvironment in which β cells are born is critical. However, to date, it remains unknown whether the changing architecture of the pancreatic epithelium impacts the fate of cells therein. An emerging challenge in the field is to elucidate how progenitors are allocated during key events, such as the stratification and subsequent resolution of the pre-pancreatic epithelium, as well as the formation of lumens and branches. Here, we assess the progenitor epithelium and examine how it might influence the emergence of pancreatic multipotent progenitors (MPCs), which give rise to β cells and other pancreatic lineages. PMID:26216134

  6. [CYSTEAMINE-INDUCED MODIFICATION OF CYTOGENETIC DAMAGES TO THE CORNEAL EPITHELIUM OF MICE EXPOSED TO CORPUSCULAR RADIATION WITH VARYING LINEAR TRANSFER ENERGIES].

    PubMed

    Vorozhtsova, S V; Bulynina, T M; Molokanov, A G; Ivanov, A A

    2015-01-01

    Cytogenetic damages to cells of the corneal epithelium were studied in mice exposed to protons (10, 25, 50 and 645 MeV), ions of boron, carbon and neon, and X-rays (180 keV) within the dose range from 25 to 750 cGy and injected with a radioprotector. Animals were subjected to a single exposure. The protective effect of β-mercaptoethylamine was tested in the experiment. The radioprotector (0.2 ml) was introduced intraperitoneally 30 minutes before exposure in 350 mI/kg dose. Control animals received the same amount of sodium chloride solution. The animals were sacrificed by cervical dislocation in 24 and 72 hrs. after exposure. It was shown that cysteamine effectively protects in vivo corneal epithelium cells of mice exposed to electromagnetic radiation or protons in a broad energy spectrum (10 to 645 MeV), and to a broad range of radiation doses (25 to 750 cGy), as judged from levels of aberrant mitosis and mitotic activity. The radioprotector exhibited the highest effectiveness in animals exposed to the doses of 50 to 300 cGy. These findings prove that cysteamine may potentially be used for pharmacological protection from protons. The radioprotector failed to prevent chromosomal aberrations after exposure to heavy charged particles of boron, carbon and neon, which implies the need to design radioprotectors against this type of corpuscular radiation specifically.

  7. [CYSTEAMINE-INDUCED MODIFICATION OF CYTOGENETIC DAMAGES TO THE CORNEAL EPITHELIUM OF MICE EXPOSED TO CORPUSCULAR RADIATION WITH VARYING LINEAR TRANSFER ENERGIES].

    PubMed

    Vorozhtsova, S V; Bulynina, T M; Molokanov, A G; Ivanov, A A

    2015-01-01

    Cytogenetic damages to cells of the corneal epithelium were studied in mice exposed to protons (10, 25, 50 and 645 MeV), ions of boron, carbon and neon, and X-rays (180 keV) within the dose range from 25 to 750 cGy and injected with a radioprotector. Animals were subjected to a single exposure. The protective effect of β-mercaptoethylamine was tested in the experiment. The radioprotector (0.2 ml) was introduced intraperitoneally 30 minutes before exposure in 350 mI/kg dose. Control animals received the same amount of sodium chloride solution. The animals were sacrificed by cervical dislocation in 24 and 72 hrs. after exposure. It was shown that cysteamine effectively protects in vivo corneal epithelium cells of mice exposed to electromagnetic radiation or protons in a broad energy spectrum (10 to 645 MeV), and to a broad range of radiation doses (25 to 750 cGy), as judged from levels of aberrant mitosis and mitotic activity. The radioprotector exhibited the highest effectiveness in animals exposed to the doses of 50 to 300 cGy. These findings prove that cysteamine may potentially be used for pharmacological protection from protons. The radioprotector failed to prevent chromosomal aberrations after exposure to heavy charged particles of boron, carbon and neon, which implies the need to design radioprotectors against this type of corpuscular radiation specifically. PMID:26292425

  8. Engineering Airway Epithelium

    PubMed Central

    Soleas, John P.; Paz, Ana; Marcus, Paula; McGuigan, Alison; Waddell, Thomas K.

    2012-01-01

    Airway epithelium is constantly presented with injurious signals, yet under healthy circumstances, the epithelium maintains its innate immune barrier and mucociliary elevator function. This suggests that airway epithelium has regenerative potential (I. R. Telford and C. F. Bridgman, 1990). In practice, however, airway regeneration is problematic because of slow turnover and dedifferentiation of epithelium thereby hindering regeneration and increasing time necessary for full maturation and function. Based on the anatomy and biology of the airway epithelium, a variety of tissue engineering tools available could be utilized to overcome the barriers currently seen in airway epithelial generation. This paper describes the structure, function, and repair mechanisms in native epithelium and highlights specific and manipulatable tissue engineering signals that could be of great use in the creation of artificial airway epithelium. PMID:22523471

  9. Ultrastructural localization of acid phosphatase in nonhuman primate vaginal epithelium.

    PubMed

    King, B F

    1985-01-01

    The vagina of the rhesus monkey is lined by a stratified squamous epithelium. However, little is known regarding the cytochemical composition of its cell organelles and the substances found in the intercellular spaces. In this study we have examined the ultrastructural distribution of acid phosphatase in the vaginal epithelium. In basal and parabasal cells reaction product was found in some Golgi cisternae and vesicles and in a variety of cytoplasmic granules. Reaction product was also found in some, but not all, membrane-coating granules. In the upper layers of the epithelium, the membrane-coating granules extruded their contents and acid phosphatase was localized in the intercellular spaces. The possible roles of acid phosphatase in keratinization, desquamation, or modification of substances in the intercellular compartment are discussed.

  10. Apoptosis and the Airway Epithelium

    PubMed Central

    White, Steven R.

    2011-01-01

    The airway epithelium functions as a barrier and front line of host defense in the lung. Apoptosis or programmed cell death can be elicited in the epithelium as a response to viral infection, exposure to allergen or to environmental toxins, or to drugs. While apoptosis can be induced via activation of death receptors on the cell surface or by disruption of mitochondrial polarity, epithelial cells compared to inflammatory cells are more resistant to apoptotic stimuli. This paper focuses on the response of airway epithelium to apoptosis in the normal state, apoptosis as a potential regulator of the number and types of epithelial cells in the airway, and the contribution of epithelial cell apoptosis in important airways diseases. PMID:22203854

  11. Effects of CO2 inhalation exposure on mice vomeronasal epithelium.

    PubMed

    Hacquemand, Romain; Buron, Gaelle; Pourié, Gregory; Karrer, Melanie; Jacquot, Laurence; Brand, Gerard

    2010-08-01

    Nasal epitheliums are the first sites of the respiratory tract in contact with the external environment and may therefore be susceptible to damage from exposure to many toxic volatile substances (i.e., volatile organic components, vapors, and gases). In the field of inhalation toxicology, a number of studies have considered the main olfactory epithelium, but few have dealt with the epithelium of the vomeronasal organ (VNO). However, in several species such as in rodents, the VNO (an organ of pheromone detection) plays an important role in social interactions, and alterations of this organ are known to induce adaptative behavioral disturbances. Among volatile toxicants, health effects of inhaled gases have been thoroughly investigated, especially during CO(2) inhalation because of its increasing atmospheric concentration. Therefore, this work was designed to examine the effects of 3% CO(2) inhalation on VNO in two different exposure conditions (5 h/day and 12 h/day) in mice. Behavioral sensitivity tests to urine of congener and histological measurements of VNO were conducted before, during (weeks 1-4), and after (weeks 5-8) CO(2) inhalation exposures. Results showed no significant modifications of behavioral responses to urine, but there were significant changes of both cell number and thickness of the VNO epithelium. Moreover, the findings indicated a selectively dose-dependent effect of CO(2), and further research could use other gases in the same manner for comparison.

  12. Effects of CO2 inhalation exposure on mice vomeronasal epithelium.

    PubMed

    Hacquemand, Romain; Buron, Gaelle; Pourié, Gregory; Karrer, Melanie; Jacquot, Laurence; Brand, Gerard

    2010-08-01

    Nasal epitheliums are the first sites of the respiratory tract in contact with the external environment and may therefore be susceptible to damage from exposure to many toxic volatile substances (i.e., volatile organic components, vapors, and gases). In the field of inhalation toxicology, a number of studies have considered the main olfactory epithelium, but few have dealt with the epithelium of the vomeronasal organ (VNO). However, in several species such as in rodents, the VNO (an organ of pheromone detection) plays an important role in social interactions, and alterations of this organ are known to induce adaptative behavioral disturbances. Among volatile toxicants, health effects of inhaled gases have been thoroughly investigated, especially during CO(2) inhalation because of its increasing atmospheric concentration. Therefore, this work was designed to examine the effects of 3% CO(2) inhalation on VNO in two different exposure conditions (5 h/day and 12 h/day) in mice. Behavioral sensitivity tests to urine of congener and histological measurements of VNO were conducted before, during (weeks 1-4), and after (weeks 5-8) CO(2) inhalation exposures. Results showed no significant modifications of behavioral responses to urine, but there were significant changes of both cell number and thickness of the VNO epithelium. Moreover, the findings indicated a selectively dose-dependent effect of CO(2), and further research could use other gases in the same manner for comparison. PMID:19924548

  13. Ductal barriers in mammary epithelium

    PubMed Central

    Owens, Mark B; Hill, Arnold DK; Hopkins, Ann M

    2013-01-01

    Tissue barriers play an integral role in the biology and pathobiology of mammary ductal epithelium. In normal breast physiology, tight and adherens junctions undergo dynamic changes in permeability in response to hormonal and other stimuli, while several of their proteins are directly involved in mammary tumorigenesis. This review describes first the structure of mammary ductal epithelial barriers and their role in normal mammary development, examining the cyclical changes in response to puberty, pregnancy, lactation and involution. It then examines the role of adherens and tight junctions and the participation of their constituent proteins in mammary tumorigenic functions such as migration, invasion and metastasis. Finally, it discusses the potential of these adhesion proteins as both prognostic biomarkers and potential therapeutic targets in breast cancer. PMID:24665412

  14. The junctional epithelium originates from the odontogenic epithelium of an erupted tooth.

    PubMed

    Yajima-Himuro, Sara; Oshima, Masamitsu; Yamamoto, Gou; Ogawa, Miho; Furuya, Madoka; Tanaka, Junichi; Nishii, Kousuke; Mishima, Kenji; Tachikawa, Tetsuhiko; Tsuji, Takashi; Yamamoto, Matsuo

    2014-05-02

    The junctional epithelium (JE) is an epithelial component that is directly attached to the tooth surface and has a protective function against periodontal diseases. In this study, we determined the origin of the JE using a bioengineered tooth technique. We transplanted the bioengineered tooth germ into the alveolar bone with an epithelial component that expressed green fluorescence protein. The reduced enamel epithelium from the bioengineered tooth fused with the oral epithelium, and the JE was apparently formed around the bioengineered tooth 50 days after transplantation. Importantly, the JE exhibited green fluorescence for at least 140 days after transplantation, suggesting that the JE was not replaced by oral epithelium. Therefore, our results demonstrated that the origin of the JE was the odontogenic epithelium, and odontogenic epithelium-derived JE was maintained for a relatively long period.

  15. Thymus epithelium induces tissue-specific tolerance

    PubMed Central

    1993-01-01

    Most current models of T cell development include a positive selection step in the thymus that occurs when T cells interact with thymic epithelium and a negative selection step after encounters with bone marrow-derived cells. We show here that developing T cells are tolerized when they recognize antigens expressed by thymic epithelium, that the tolerance is tissue specific, and that it can occur by deletion of the reactive T cells. PMID:8459209

  16. Electrodeposition of pronectin for titanium to augment gingival epithelium adhesion.

    PubMed

    Kawabata, Shingo; Asano, Kazunari; Miyazawa, Atsuko; Satoh, Tazuko; Tabata, Yasuhiko

    2013-05-01

    This paper is one trial of surface modification of titanium with pronectin F+ (PN) of an artificial protein to enhance gingival adhesion. Titanium plates were electrodeposited in the PN solution to prepare PN-electrodeposited titanium plates. When PN detachment from the PN-electrodeposited titanium plates was investigated, no detachment was observed, in contrast to the case of titanium plates simply coated with PN. A cell culture experiment demonstrated that electrodeposited PN had an inherent ability to enhance the initial attachment of gingival epithelial cells. The PN-electrodeposited titanium plates were implanted between the gingival epithelium and the underlying bone tissue of rabbits to evaluate epithelial growth on the plates and their gingival adhesion. Non-treated and PN-coated titanium plates were used as controls. PN electrodeposition enhanced epithelial growth and adhesion of titanium plates to a significantly great extent compared with PN-coated plates. These findings demonstrate that PN electrodeposition is a promising method to enhance epithelium adhesion onto a titanium surface.

  17. Expression of acid phosphatase in the seminiferous epithelium of vertebrates.

    PubMed

    Peruquetti, R L; Taboga, S R; Azeredo-Oliveira, M T V

    2010-01-01

    Acid phosphatases (AcPs) are known to provide phosphate to tissues that have high energy requirements, especially during development, growth and maturation. During spermatogenesis AcP activity is manifested in heterophagous lysosomes of Sertoli cells. This phagocytic function appears to be hormone-independent. We examined the expression pattern of AcP during the reproductive period of four species belonging to different vertebrate groups: Tilapia rendalli (Teleostei, Cichlidae), Dendropsophus minutus (Amphibia, Anura), Meriones unguiculatus (Mammalia, Rodentia), and Oryctolagus cuniculus (Mammalia, Lagomorpha). To demonstrate AcP activity, cryosections were processed for enzyme histochemistry by a modification of the method of Gömöri. AcP activity was similar in the testes of these four species. Testes of T. rendalli, D. minutus and M. unguiculatus showed an intense reaction in the Sertoli cell region. AcP activity was detected in the testes of D. minutus and O. cuniculus in seminiferous epithelium regions, where cells are found in more advanced stages of development. The seminiferous epithelium of all four species exhibited AcP activity, mainly in the cytoplasm of either Sertoli cells or germ cells. These findings reinforce the importance of AcP activity during the spermatogenesis process in vertebrates. PMID:20391346

  18. Expression of keratins in mouse vaginal epithelium.

    PubMed

    Gimenez-Conti, I B; Lynch, M; Roop, D; Bhowmik, S; Majeski, P; Conti, C J

    1994-05-01

    In the epithelium of the rodent vagina proliferation and differentiation are tightly regulated by ovarian hormones. Estrogens stimulate proliferation and squamous differentiation, whereas progesterone redirects differentiation to a mucus-secreting epithelium formed by goblet-like cells. In the present study, we used monospecific keratin antibodies to show the expression and distribution of keratins in SENCAR mouse vaginal epithelium in different stages of the estral cycle and in ovariectomized animals. In ovariectomized animals, the vaginal epithelium expressed K6, K8, K13 and K14, but not K1. After estrogen treatment, K1 was expressed. During proestrus and estrus, the keratin pattern was essentially identical to that observed in 17 beta-estradiol-stimulated animals. In contrast, during the progestational stages (metaestrus and diestrus) or after progesterone treatment of ovariectomized mice, the most relevant change was the loss of K1. Together, these results show that K1 expression is induced by estrogens in the vaginal epithelium. In contrast, K6, K8, K13 and K14 are constitutively expressed even when squamous differentiation is not observed.

  19. Olfactory epithelium changes in germfree mice

    PubMed Central

    François, Adrien; Grebert, Denise; Rhimi, Moez; Mariadassou, Mahendra; Naudon, Laurent; Rabot, Sylvie; Meunier, Nicolas

    2016-01-01

    Intestinal epithelium development is dramatically impaired in germfree rodents, but the consequences of the absence of microbiota have been overlooked in other epithelia. In the present study, we present the first description of the bacterial communities associated with the olfactory epithelium and explored differences in olfactory epithelium characteristics between germfree and conventional, specific pathogen-free, mice. While the anatomy of the olfactory epithelium was not significantly different, we observed a thinner olfactory cilia layer along with a decreased cellular turn-over in germfree mice. Using electro-olfactogram, we recorded the responses of olfactory sensitive neuronal populations to various odorant stimulations. We observed a global increase in the amplitude of responses to odorants in germfree mice as well as altered responses kinetics. These changes were associated with a decreased transcription of most olfactory transduction actors and of olfactory xenobiotic metabolising enzymes. Overall, we present here the first evidence that the microbiota modulates the physiology of olfactory epithelium. As olfaction is a major sensory modality for most animal species, the microbiota may have an important impact on animal physiology and behaviour through olfaction alteration. PMID:27089944

  20. [Autocrine growth mechanisms of cholesteatoma epithelium].

    PubMed

    Schilling, V; Holly, A; Bujía, J; Schulz, P

    1993-07-01

    Transforming growth factor alpha (TGF alpha) and interleukin 1 alpha (IL-1 alpha) are known to be produced by normal human keratinocytes stimulating their proliferation. The distribution and expression of TGF alpha and IL-1 alpha were examined in specimens of middle ear cholesteatoma by means of immunohistochemical methods using a monoclonal antibody against TGF alpha and a polyclonal one against IL-1 alpha. Normal retroauricular skin was stained for comparison. Staining for TGF alpha was consistently stronger in cholesteatoma epithelium than in normal epidermis, and encompassed all epithelial cell layers. Immune cells occurring in the stroma of cholesteatoma also reacted positively for TGF alpha. The intensity of staining for IL-1 alpha was markedly stronger in cholesteatoma tissue than in normal epidermis. All cellular layers of the squamous epithelium of cholesteatoma stained strongly and uniformly for IL-1 alpha, whereas the keratin layer was negative for IL-1 alpha. In the connective tissue beneath the cholesteatoma epithelium intensely positive cells were scattered between negative stromal cells. These data are consistent with autocrine stimulation of the squamous epithelium of cholesteatoma by TGF alpha and IL-1 alpha as well as with a paracrine stimulation by immune cells. Both factors contribute to the unrestrained growth of cholesteatoma in the middle ear cavity.

  1. Mechanically patterning the embryonic airway epithelium

    PubMed Central

    Varner, Victor D.; Gleghorn, Jason P.; Miller, Erin; Radisky, Derek C.; Nelson, Celeste M.

    2015-01-01

    Collections of cells must be patterned spatially during embryonic development to generate the intricate architectures of mature tissues. In several cases, including the formation of the branched airways of the lung, reciprocal signaling between an epithelium and its surrounding mesenchyme helps generate these spatial patterns. Several molecular signals are thought to interact via reaction-diffusion kinetics to create distinct biochemical patterns, which act as molecular precursors to actual, physical patterns of biological structure and function. Here, however, we show that purely physical mechanisms can drive spatial patterning within embryonic epithelia. Specifically, we find that a growth-induced physical instability defines the relative locations of branches within the developing murine airway epithelium in the absence of mesenchyme. The dominant wavelength of this instability determines the branching pattern and is controlled by epithelial growth rates. These data suggest that physical mechanisms can create the biological patterns that underlie tissue morphogenesis in the embryo. PMID:26170292

  2. Odors Discrimination by Olfactory Epithelium Biosensor

    NASA Astrophysics Data System (ADS)

    Liu, Qingjun; Hu, Ning; Ye, Weiwei; Zhang, Fenni; Wang, Hua; Wang, Ping

    2011-09-01

    Humans are exploring the bionic biological olfaction to sense the various trace components of gas or liquid in many fields. For achieving the goal, we endeavor to establish a bioelectronic nose system for odor detection by combining intact bioactive function units with sensors. The bioelectronic nose is based on the olfactory epithelium of rat and microelectrode array (MEA). The olfactory epithelium biosensor generates extracellular potentials in presence of odor, and presents obvious specificity under different odors condition. The odor response signals can be distinguished with each other effectively by signal sorting. On basis of bioactive MEA hybrid system and the improved signal processing analysis, the bioelectronic nose will realize odor discrimination by the specific feature of signals response to various odors.

  3. Confocal fluorescence microendoscopy of bronchial epithelium

    NASA Astrophysics Data System (ADS)

    Lane, Pierre M.; Lam, Stephen; McWilliams, Annette; Leriche, Jean C.; Anderson, Marshall W.; Macaulay, Calum E.

    2009-03-01

    Confocal microendoscopy permits the acquisition of high-resolution real-time confocal images of bronchial mucosa via the instrument channel of an endoscope. We report here on the construction and validation of a confocal fluorescence microendoscope and its use to acquire images of bronchial epithelium in vivo. Our objective is to develop an imaging method that can distinguish preneoplastic lesions from normal epithelium to enable us to study the natural history of these lesions and the efficacy of chemopreventive agents without biopsy removal of the lesion that can introduce a spontaneous regression bias. The instrument employs a laser-scanning engine and bronchoscope-compatible confocal probe consisting of a fiber-optic image guide and a graded-index objective lens. We assessed the potential of topical application of physiological pH cresyl violet (CV) as a fluorescence contrast-enhancing agent for the visualization of tissue morphology. Images acquired ex vivo with the confocal microendoscope were first compared with a bench-top confocal fluorescence microscope and conventional histology. Confocal images from five sites topically stained with CV were then acquired in vivo from high-risk smokers and compared to hematoxylin and eosin stained sections of biopsies taken from the same site. Sufficient contrast in the confocal imagery was obtained to identify cells in the bronchial epithelium. However, further improvements in the miniature objective lens are required to provide sufficient axial resolution for accurate classification of preneoplastic lesions.

  4. Development of the ovarian follicular epithelium.

    PubMed

    Rodgers, R J; Lavranos, T C; van Wezel, I L; Irving-Rodgers, H F

    1999-05-25

    A lot is known about the endocrine control of the development of ovarian follicles, but a key question now facing researchers is which molecular and cellular processes take part in control of follicular growth and development. The growth and development of ovarian follicles occurs postnatally and throughout adult life. In this review, we focus on the follicular epithelium (membrana granulosa) and its basal lamina. We discuss a model of how granulosa cells arise from a population of stem cells and then enter different lineages before differentiation. The structure of the epithelium at the antral stage of development is presented, and the effects that follicle growth has on the behavior of the granulosa cells are discussed. Finally, we discuss the evidence that during follicle development the follicular basal lamina changes in composition. This would be expected if the behavior of the granulosa cells changes, or if the permeability of the basal lamina changes. It will be evident that the follicular epithelium has similarities to other epithelia in the body, but that it is more dynamic, as gross changes occur during the course of follicle development. This basic information will be important for the development of future reproductive technologies in both humans and animals, and possibly for understanding polycystic ovarian syndrome in women. PMID:10411332

  5. Novel organelles in primate retinal epithelium.

    PubMed

    Biesemeier, A; Gouras, P

    2016-10-01

    We are investigating age-related changes in organelles in monkey retinal epithelium using transmission and analytic electron microscopy. We previously described a circular organelle in retinal epithelium with a diameter of about 0.5μm. The organelle is unique in containing a single, round vacuole within an otherwise electron dense interior. We suggested that the organelle might be a melanosome with lysosomal properties. We now find that there are two similar organelles with such a single vacuole but which differ in their chemical composition, electron density, cell location and according to age. Epon embedded sections from the macular epithelium of seven monkeys, ranging from 1 to 35 years of age, were examined by transmission electron microscopy. A seven year old monkey was processed for analytic electron microscopy to determine the chemical composition of the organelles. The number and location of the organelles in the retinal epithelium were determined. The chemical composition of these two organelles was different. One of the organelles contained high mole fractions of oxygen and nitrogen and little phosphorous characteristic of melanin; the other had little oxygen and nitrogen and higher mole fractions of phosphorous uncharacteristic of melanin, but more common with lysosomal organelles. The latter had an electron dense rim around the vacuole, a less electron dense interior than the melanin containing organelle and also contained iron. The melanin containing organelle was more common in young monkeys and in the middle third of the cell. The organelle without melanin was more common in old monkeys and localized in the basal third of the cell. Two similarly vacuolated organelles, not identified before in retinal epithelium, differ in their chemical composition. One contains melanin; the other does not. The former is more common in young and the latter more common in old monkeys. This suggests reorganization and or degradation of melanin-containing organelles

  6. Novel organelles in primate retinal epithelium.

    PubMed

    Biesemeier, A; Gouras, P

    2016-10-01

    We are investigating age-related changes in organelles in monkey retinal epithelium using transmission and analytic electron microscopy. We previously described a circular organelle in retinal epithelium with a diameter of about 0.5μm. The organelle is unique in containing a single, round vacuole within an otherwise electron dense interior. We suggested that the organelle might be a melanosome with lysosomal properties. We now find that there are two similar organelles with such a single vacuole but which differ in their chemical composition, electron density, cell location and according to age. Epon embedded sections from the macular epithelium of seven monkeys, ranging from 1 to 35 years of age, were examined by transmission electron microscopy. A seven year old monkey was processed for analytic electron microscopy to determine the chemical composition of the organelles. The number and location of the organelles in the retinal epithelium were determined. The chemical composition of these two organelles was different. One of the organelles contained high mole fractions of oxygen and nitrogen and little phosphorous characteristic of melanin; the other had little oxygen and nitrogen and higher mole fractions of phosphorous uncharacteristic of melanin, but more common with lysosomal organelles. The latter had an electron dense rim around the vacuole, a less electron dense interior than the melanin containing organelle and also contained iron. The melanin containing organelle was more common in young monkeys and in the middle third of the cell. The organelle without melanin was more common in old monkeys and localized in the basal third of the cell. Two similarly vacuolated organelles, not identified before in retinal epithelium, differ in their chemical composition. One contains melanin; the other does not. The former is more common in young and the latter more common in old monkeys. This suggests reorganization and or degradation of melanin-containing organelles

  7. Ultrastructural observations on the terminal segment epithelium of the seminiferous tubule of West African dwarf goats.

    PubMed Central

    Ezeasor, D N

    1986-01-01

    In the testes of West African dwarf goats, modified Sertoli cells comprise the major component of the terminal segment epithelium. They resemble Sertoli cells proper but differ in the paucity of agranular endoplasmic reticulum and lipid droplets. Cell attachment devices present include rudimentary desmosomes and occasional multiple contacts of opposing plasma membranes, interrupted by segments of slightly expanded intercellular space. A few generative cells are present in the proximal zone of the epithelium, but their development appears to terminate as early spermatids which hang loosely on the luminal surface. The middle zone epithelium comprises vacuolated cells lying among other cells containing abundant microtubules in their subapical cytoplasm. Globular expansions of the intercellular space are also apparent. The terminal plug contains two cell types. Type I are inclined, columnar cells which contain profuse arrays of agranular endoplasmic reticulum in their apical cytoplasm. Type II are smaller cells located at the apex of the plug. Each possesses cytoplasmic processes, which surround the apices of Type I cells. The modified Sertoli cells of all zones and the Type II plug cells contain remnants of spermatozoa at different stages of degradation. The general absence of developing generative cells in the terminal segment epithelium may be related to the paucity of agranular endoplasmic reticulum in the basal cytoplasm of modified Sertoli cells and the absence of typical Sertoli-Sertoli junctional specialisations. Structural modifications evident in the middle and distal zones facilitate distalward movement of materials, while the attenuation and modification of the lumen distally may facilitate phagocytosis of abnormal spermatozoa. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 PMID:3693043

  8. Defective Barrier Function in Neosquamous Epithelium

    PubMed Central

    Jovov, Biljana; Shaheen, Nicholas J; Orlando, Geraldine S.; Djukic, Zorka; Orlando, Roy C.

    2013-01-01

    BACKGROUND Radiofrequency ablation (RFA) of Barrett’s esophagus (BE) is a common strategy for the prevention of esophageal adenocarcinoma (EAC). After RFA, the ablated esophagus heals on acid suppressive therapy, and is re-populated with a stratified squamous epithelium, referred to as ‘neosquamous epithelium (NSE).’ Because the ability of the NSE to protect the underlying tissue from recurrent insult by reflux is unclear, we assessed the barrier function of NSE by comparing it to that of the native upper squamous epithelium (USE) in subjects having undergone RFA. METHODS At varying intervals following RFA, the barrier function of NSE and USE were assessed in endoscopic biopsies by light and electron microscopy, and by measurement of electrical resistance (RT) and fluorescein flux in mini-Ussing chambers. Chamber results were further compared with results from control biopsies (healthy distal esophagus). A claudin expression profile in the tight junctions (TJ) of NSE and USE was determined using qRT-PCR. Differential expression of claudin 4 between NSE and USE was assayed by immunoblots. RESULTS USE was histologically normal while NSE showed dilated intercellular spaces and marked eosinophilia. NSE was also more permeable than USE and healthy controls, having lower mean RT and higher fluorescein fluxes. Abnormally low RT values for NSE were unrelated to the time period following RFA (or number of prior RFA sessions), being abnormal even 26 months after RFA. Abnormal permeability in NSE was associated with significantly lower values for claudin-4 and claudin-10 than in USE. CONCLUSIONS NSE commonly exhibits defective barrier function. Since this defect will make it vulnerable to injury, inflammation and destruction by acidic and weakly acidic refluxates, it may in part explain incidences of recurrence of BE following ablation. PMID:23318477

  9. Ontogeny of the mouse vocal fold epithelium

    PubMed Central

    Lungova, Vlasta; Verheyden, Jamie M.; Herriges, John; Sun, Xin; Thibeault, Susan L.

    2015-01-01

    This investigation provides the first systematic determination of the cellular and molecular progression of vocal fold (VF) epithelium development in a murine model. We define five principal developmental events that constitute the progression from VF initiation in the embryonic anterior foregut tube to fully differentiated and functional adult tissue. These developmental events include (1) the initiation of the larynx and vocal folds with apposition of the lateral walls of the primitive laryngopharynx (embryonic (E) day 10.5); (2) the establishment of the epithelial lamina with fusion of the lateral walls of the primitive laryngopharynx (E11.5); (3) the epithelial lamina recanalization and separation of VFs (E13.5–18.5); (4) the stratification of the vocal folds (E13.5–18.5); and (5) the maturation of vocal fold epithelium (postnatal stages). The illustration of these morphogenetic events is substantiated by dynamic changes in cell proliferation and apoptosis, as well as the expression pattern of key transcription factors, FOXA2, SOX2 and NKX2-1 that specify and pattern the foregut endoderm. Furthermore, we documented the gradual conversion of VF epithelial cells from simple precursors expressing cytokeratins 8 and 18 in the embryo into mature stratified epithelial cells also expressing cytokeratins 5 and 14 in the adult. Interestingly, in the adult, cytokeratins 5 and 14 appear to be expressed in all cell layers in the VF, in contrast to their preferential localization to the basal cell layer in surrounding epithelium. To begin investigating the role of signaling molecules in vocal fold development, we characterized the expression pattern of SHH pathway genes, and how loss of Shh affects vocal fold development in the mutant. This study defines the cellular and molecular context and serves as the necessary foundation for future functional investigations of VF formation. PMID:25601450

  10. Objectivity in the classification of tumours of the nasal epithelium

    PubMed Central

    Michaels, L.; Hyams, V. J.

    1975-01-01

    A survey of tumours derived from each of the four cell types of nasal epithelium is presented. Criticism is levelled at the adoption of additional terms for tissue types such as lympho-epithelium and transitional cell epithelium and tumours said to be derived from them. Electron microscopy is of assistance in classification particularly in the detection of evidence of keratin synthesis. The proposed classification of tumours of the nasal epithelium is: (1) Pseudostratified columnar epithelium: (a) papillary adenoma, (b) papillary carcinoma. (2) Squamous epithelium: (a) everted squamous papilloma, (b) inverted papilloma, (c) squamous carcinoma of any grade of differentiation from well differentiated to undifferentiated. (3) Melanocyte: malignant melanoma. (4) Olfactory neuroepithelium: olfactory neuroblastoma. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 13Fig. 14Fig. 15Fig. 16Fig. 17Fig. 18Fig. 19Fig. 21Fig. 20 PMID:1197175

  11. Expression profile of maize (Zea mays) scutellar epithelium during imbibition.

    PubMed

    Tnani, Hedia; García-Muniz, Nora; Vicient, Carlos M; López-Ribera, Ignacio

    2012-09-15

    The scutellum is a shield-shaped structure surrounding the embryo axis in grass species. The scutellar epithelium (Sep) is a monolayer of cells in contact with the endosperm. The Sep plays an important role during seed germination in the secretion of gibberellins and hydrolytic enzymes and in the transport of the hydrolized products to the growing embryo. We identified 30 genes predominantly expressed after imbibition in the Sep as compared to other parts of the scutellum. A high proportion of these genes is involved in metabolic processes. Some other identified genes are involved in the synthesis or modification of cell walls, which may be reflected in the changes of cell shape and cell wall composition that can be observed during imbibition. One of the genes encodes a proteinase that belongs to a proteinase family typical of carnivorous plants. Almost nothing is known about their role in other plants or organs, but the scutellar presence may point to a "digestive" function during germination. Genes involved in the production of energy and the transport of peptides were also identified.

  12. Tumorigenesis and peritoneal colonization from fallopian tube epithelium.

    PubMed

    Eddie, Sharon L; Quartuccio, Suzanne M; Ó hAinmhir, Eoghainin; Moyle-Heyrman, Georgette; Lantvit, Dan D; Wei, Jian-Jun; Vanderhyden, Barbara C; Burdette, Joanna E

    2015-08-21

    Ovarian cancer is the most lethal gynecological malignancy, primarily because its origin and initiation factors are unknown. A secretory murine oviductal epithelial (MOE) model was generated to address the hypothesis that the fallopian tube is an origin for high-grade serous cancer. MOE cells were stably altered to express mutation in p53, silence PTEN, activate AKT, and amplify KRAS alone and in combination, to define if this cell type gives rise to tumors and what genetic alterations are required to drive malignancy. Cell lines were characterized in vitro and allografted into mice. Silencing PTEN formed high-grade carcinoma with wide spread tumor explants including metastasis into the ovary. Addition of p53 mutation to PTEN silencing did not enhance this phenotype, whereas addition of KRAS mutation reduced survival. Interestingly, PTEN silencing and KRAS mutation originating from ovarian surface epithelium generated endometrioid carcinoma, suggesting that different cellular origins with identical genetic manipulations can give rise to distinct cancer histotypes. Defining the roles of specific signaling modifications in tumorigenesis from the fallopian tube/oviduct is essential for early detection and development of targeted therapeutics. Further, syngeneic MOE allografts provide an ideal model for pre-clinical testing in an in vivo environment with an intact immune system.

  13. Home Modification

    MedlinePlus

    ... it is important to consider certain safety modifications. Adaptations such as those in the following list can ... The importance of a Consumer Perspective in Home Adaptation of Alzheimer’s Households” (Chapter 6 pp 91-112) ...

  14. Ubiquitin modifications

    PubMed Central

    Swatek, Kirby N; Komander, David

    2016-01-01

    Protein ubiquitination is a dynamic multifaceted post-translational modification involved in nearly all aspects of eukaryotic biology. Once attached to a substrate, the 76-amino acid protein ubiquitin is subjected to further modifications, creating a multitude of distinct signals with distinct cellular outcomes, referred to as the 'ubiquitin code'. Ubiquitin can be ubiquitinated on seven lysine (Lys) residues or on the N-terminus, leading to polyubiquitin chains that can encompass complex topologies. Alternatively or in addition, ubiquitin Lys residues can be modified by ubiquitin-like molecules (such as SUMO or NEDD8). Finally, ubiquitin can also be acetylated on Lys, or phosphorylated on Ser, Thr or Tyr residues, and each modification has the potential to dramatically alter the signaling outcome. While the number of distinctly modified ubiquitin species in cells is mind-boggling, much progress has been made to characterize the roles of distinct ubiquitin modifications, and many enzymes and receptors have been identified that create, recognize or remove these ubiquitin modifications. We here provide an overview of the various ubiquitin modifications present in cells, and highlight recent progress on ubiquitin chain biology. We then discuss the recent findings in the field of ubiquitin acetylation and phosphorylation, with a focus on Ser65-phosphorylation and its role in mitophagy and Parkin activation. PMID:27012465

  15. Flow cytometric DNA analysis of corneal epithelium.

    PubMed

    Burns, E R; Roberson, M C; Brown, M F; Shock, J P; Pipkin, J L; Hinson, W G; Anson, J F

    1990-03-01

    We have modified an existing technique in order to perform DNA analysis by flow cytometry (FCM) of corneal epithelium from the mouse, rat, chicken, rabbit, and human. This protocol permitted an investigation of human corneal scrapings from several categories: normal, aphakic bullous keratopathy (ABK), keratoconus (KC), Fuch's dystrophy, edema, epithelial dysplasia, and lipid degeneration. No abnormal characteristic cell-kinetic profile was detected when averaged DNA histograms were compared statistically between the normal and either ABK, KC, edema, or Fuch's dystrophy groups. Abnormal DNA histograms were recorded for cell samples that were taken 1) from three individuals who had epithelial dysplasia and 2) from one individual diagnosed with lipid degeneration. The former condition was characterized by histograms that had a subpopulation of cells with an aneuploid amount of DNA or had higher than normal percentages of cells in the S and G2 + M phases of the cell cycle. Corneal cells from the patient who had lipid degeneration had an abnormally high percentage of cells in the G2 + M phases of the cell cycle. The availability of accurate DNA flow cytometric analysis of corneal epithelium allows further studies on this issue from both experimental and clinical situations.

  16. Transitory cell attachments in the differentiating glomerular epithelium of the opossum metanephros.

    PubMed

    Krause, W J; Cutts, J H

    1980-01-01

    Numerous transitory intercellular attachments are observed between the central, lateral surfaces of adjacent glomerular epithelial cells in the differentiating renal corpuscle. The junctions are characterized by an increased electron density of the adjacent cell membranes and cytoplasm. The intervening intercellular space may contain an amorphous material of moderate electron density. The distribution and position of such temporary cell attachments, together with their modification and subsequent loss during the differentiation of podocytes, suggest that they play an important role in the histogenesis of the glomerular epithelium.

  17. [Lifestyle modifications].

    PubMed

    Kawano, Yuhei

    2015-11-01

    Lifestyle modifications are important in the prevention and treatment of hypertension. The Japanese Society of Hypertension Guidelines for the Management of Hypertension (JSH2014) recommend salt reduction (< 6 g/day), increased intake of vegetables/fruit and fish (fish oil), reduced intake of cholesterol and saturated fatty acids, weight loss (body mass index < 25kg/m2), exercise (≥ 30 min/day), reduction of alcohol intake (≤ 20-30 mL/day in men, ≤ 10-20 mL/day in women as ethanol), and quitting smoking. These lifestyle modifications are capable of reducing blood pressure and ameliorating other cardiovascular risk factors. However, the reduction in blood pressure is mild to moderate and the adherence to lifestyle modifications has been still suboptimal. PMID:26619658

  18. Spatially limited growth of an epithelium

    NASA Astrophysics Data System (ADS)

    Deforet, Maxime; Cochet, Olivier; Buguin, Axel; Silberzan, Pascal

    2012-02-01

    We present a study dealing with the growth of an epithelium on a spatially limited adhesive substrate. Adhesive patterns (typical size: 50μm to 500μm) are created by micro-fabrication techniques: A protein repellent polymeric gel homogeneously grafted on a coverslip is selectively ablated by plasma treatment through a thin layer of photoresist. The technique achieves a high resolution of patterning (around 2μm). After seeding cells (MDCK) on circular adhesive patterns, we let the monolayer grow for 30 hours after reaching the confluence. We use physical descriptors to describe migration and compaction. Two days after the confluence, we observe and characterize by confocal microscopy, the appearance of a tridimensionnal assembly of cells in the peripherical zone of the adhesive pattern (a ``rim''). Moreover using other patterns, the existence of a tissue line tension and internal pressure is investigated.

  19. Challenges and opportunities for tissue-engineering polarized epithelium.

    PubMed

    Paz, Ana C; Soleas, John; Poon, James C H; Trieu, Dennis; Waddell, Thomas K; McGuigan, Alison P

    2014-02-01

    The epithelium is one of the most important tissue types in the body and the specific organization of the epithelial cells in these tissues is important for achieving appropriate function. Since many tissues contain an epithelial component, engineering functional epithelium and understanding the factors that control epithelial maturation and organization are important for generating whole artificial organ replacements. Furthermore, disruption of the cellular organization leads to tissue malfunction and disease; therefore, engineered epithelium could provide a valuable in vitro model to study disease phenotypes. Despite the importance of epithelial tissues, a surprisingly limited amount of effort has been focused on organizing epithelial cells into artificial polarized epithelium with an appropriate structure that resembles that seen in vivo. In this review, we provide an overview of epithelial tissue organization and highlight the importance of cell polarization to achieve appropriate epithelium function. We next describe the in vitro models that exist to create polarized epithelium and summarize attempts to engineer artificial epithelium for clinical use. Finally, we highlight the opportunities that exist to translate strategies from tissue engineering other tissues to generate polarized epithelium with a functional structure.

  20. Bronchial epithelium in children: a key player in asthma.

    PubMed

    Carsin, Ania; Mazenq, Julie; Ilstad, Alexandra; Dubus, Jean-Christophe; Chanez, Pascal; Gras, Delphine

    2016-06-01

    Bronchial epithelium is a key element of the respiratory airways. It constitutes the interface between the environment and the host. It is a physical barrier with many chemical and immunological properties. The bronchial epithelium is abnormal in asthma, even in children. It represents a key component promoting airway inflammation and remodelling that can lead to chronic symptoms. In this review, we present an overview of bronchial epithelium and how to study it, with a specific focus on children. We report physical, chemical and immunological properties from ex vivo and in vitro studies. The responses to various deleterious agents, such as viruses or allergens, may lead to persistent abnormalities orchestrated by bronchial epithelial cells. As epithelium dysfunctions occur early in asthma, reprogramming the epithelium may represent an ambitious goal to induce asthma remission in children.

  1. Do Airway Epithelium Air–Liquid Cultures Represent the In Vivo Airway Epithelium Transcriptome?

    PubMed Central

    Dvorak, Anna; Tilley, Ann E.; Shaykhiev, Renat; Wang, Rui; Crystal, Ronald G.

    2011-01-01

    Human airway epithelial cells cultured in vitro at the air–liquid interface (ALI) form a pseudostratified epithelium that forms tight junctions and cilia, and produces mucin. These cells are widely used in models of differentiation, injury, and repair. To assess how closely the transcriptome of ALI epithelium matches that of in vivo airway epithelial cells, we used microarrays to compare the transcriptome of human large airway epithelial cells cultured at the ALI with the transcriptome of large airway epithelium obtained via bronchoscopy and brushing. Gene expression profiling showed that global gene expression correlated well between ALI cells and brushed cells, but with some differences. Gene expression patterns mirrored differences in proportions of cell types (ALIs have higher percentages of basal cells, whereas brushed cells have higher percentages of ciliated cells), that is, ALI cells expressed higher levels of basal cell–related genes, and brushed cells expressed higher levels of cilia-related genes. Pathway analysis showed that ALI cells had increased expression of cell cycle and proliferation genes, whereas brushed cells had increased expression of cytoskeletal organization and humoral immune response genes. Overall, ALI cells provide a good representation of the in vivo airway epithelial transcriptome, but for some biologic questions, the differences between in vitro and in vivo environments need to be considered. PMID:20525805

  2. Trachea Epithelium as a “Canary” for Cigarette Smoking-induced Biologic Phenotype of the Small Airway Epithelium*

    PubMed Central

    Turetz, Meredith L.; O’Connor, Timothy P.; Tilley, Ann E.; Strulovici-Barel, Yael; Salit, Jacqueline; Dang, David; Teater, Matthew; Mezey, Jason; Clark, Andrew G.; Crystal, Ronald G.

    2013-01-01

    The initial site of smoking-induced lung disease is the small airway epithelium, which is difficult and time consuming to sample by fiberoptic bronchoscopy. We developed a rapid, office-based procedure to obtain trachea epithelium without conscious sedation from healthy nonsmokers (n=26) and healthy smokers (n=19, 27 ± 15 pack-yr). Gene expression differences (fold-change >1.5, p<0.01, Benjamini-Hochberg correction) were assessed with Affymetrix microarrays. 1,057 probe sets were differentially expressed in healthy smokers vs nonsmokers, representing >500 genes. Trachea gene expression was compared to an independent group of small airway epithelial samples (n=23 healthy nonsmokers, n=19 healthy smokers, 25 ± 12 pack-yr). The trachea epithelium is more sensitive to smoking, responding with 3-fold more differentially-expressed genes than small airway epithelium. The trachea transcriptome paralleled the small airway epithelium, with 156 of 167 (93%) genes that are significantly upand down-regulated by smoking in the small airway epithelium showing similar direction and magnitude of response to smoking in the trachea. Trachea epithelium can be obtained without conscious sedation, representing a less invasive surrogate “canary” for smoking-induced changes in the small airway epithelium. This should prove useful in epidemiologic studies correlating gene expression with clinical outcome in assessing smoking-induced lung disease. PMID:20443905

  3. DNA Methylation Dynamics Regulate the Formation of a Regenerative Wound Epithelium during Axolotl Limb Regeneration.

    PubMed

    Aguilar, Cristian; Gardiner, David M

    2015-01-01

    The formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. One of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. We have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression patterns of keratinocytes of the wound and blastema epithelium that are involved in regeneration. We report a modulation of the expression DNMT3a, a de novo DNA methyltransferase, within the first 72 hours post injury that is dependent on nerve signaling. Treatment of skin wounds on the upper forelimb with decitabine, a DNA methyltransferase inhibitor, induced changes in gene expression and cellular behavior associated with a regenerative response. Furthermore, decitabine-treated wounds were able to participate in regeneration while untreated wounds inhibited a regenerative response. Elucidation of the specific epigenetic modifications that mediate cellular dedifferentiation likely will lead to insights for initiating a regenerative response in organisms that lack this ability.

  4. DNA Methylation Dynamics Regulate the Formation of a Regenerative Wound Epithelium during Axolotl Limb Regeneration

    PubMed Central

    Aguilar, Cristian; Gardiner, David M.

    2015-01-01

    The formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. One of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. We have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression patterns of keratinocytes of the wound and blastema epithelium that are involved in regeneration. We report a modulation of the expression DNMT3a, a de novo DNA methyltransferase, within the first 72 hours post injury that is dependent on nerve signaling. Treatment of skin wounds on the upper forelimb with decitabine, a DNA methyltransferase inhibitor, induced changes in gene expression and cellular behavior associated with a regenerative response. Furthermore, decitabine-treated wounds were able to participate in regeneration while untreated wounds inhibited a regenerative response. Elucidation of the specific epigenetic modifications that mediate cellular dedifferentiation likely will lead to insights for initiating a regenerative response in organisms that lack this ability. PMID:26308461

  5. DNA Methylation Dynamics Regulate the Formation of a Regenerative Wound Epithelium during Axolotl Limb Regeneration.

    PubMed

    Aguilar, Cristian; Gardiner, David M

    2015-01-01

    The formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. One of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. We have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression patterns of keratinocytes of the wound and blastema epithelium that are involved in regeneration. We report a modulation of the expression DNMT3a, a de novo DNA methyltransferase, within the first 72 hours post injury that is dependent on nerve signaling. Treatment of skin wounds on the upper forelimb with decitabine, a DNA methyltransferase inhibitor, induced changes in gene expression and cellular behavior associated with a regenerative response. Furthermore, decitabine-treated wounds were able to participate in regeneration while untreated wounds inhibited a regenerative response. Elucidation of the specific epigenetic modifications that mediate cellular dedifferentiation likely will lead to insights for initiating a regenerative response in organisms that lack this ability. PMID:26308461

  6. Biochemical studies of the tracheobronchial epithelium

    SciTech Connect

    Mass, M.J.; Kaufman, D.G.

    1984-06-01

    Tracheobronchial epithelium has been a focus of intense investigation in the field of chemical carcinogenesis. We have reviewed some biochemical investigations that have evolved through linkage with carcinogenesis research. These areas of investigation have included kinetics of carcinogen metabolism, identification of carcinogen metabolites, levels of carcinogen binding to DNA, and analysis of carcinogen-DNA adducts. Such studies appear to have provided a reasonable explanation for the susceptibilities of the respiratory tracts of rats and hamsters to carcinogenesis by benzo(a)pyrene. Coinciding with the attempts to understand the initiation of carcinogenesis in the respiratory tract has also been a major thrust aimed at effecting its prevention both in humans and in animal models for human bronchogenic carcinoma. These studies have concerned the effects of derivatives of vitamin A (retinoids) and their influence on normal cell biology and biochemistry of this tissue. Recent investigations have included the effects of retinoid deficiency on the synthesis of RNA and the identification of RNA species associated with this biological state, and also have included the effects of retinoids on the synthesis of mucus-related glycoproteins. Tracheal organ cultures from retinoid-deficient hamsters have been used successfully to indicate the potency of synthetic retinoids by monitoring the reversal of squamous metaplasia. Techniques applied to this tissue have also served to elucidate features of the metabolism of retinoic acid using high pressure liquid chromatography. 94 references, 9 figures, 2 tables.

  7. Stem cells of the skin epithelium

    PubMed Central

    Alonso, Laura; Fuchs, Elaine

    2003-01-01

    Tissue stem cells form the cellular base for organ homeostasis and repair. Stem cells have the unusual ability to renew themselves over the lifetime of the organ while producing daughter cells that differentiate into one or multiple lineages. Difficult to identify and characterize in any tissue, these cells are nonetheless hotly pursued because they hold the potential promise of therapeutic reprogramming to grow human tissue in vitro, for the treatment of human disease. The mammalian skin epithelium exhibits remarkable turnover, punctuated by periods of even more rapid production after injury due to burn or wounding. The stem cells responsible for supplying this tissue with cellular substrate are not yet easily distinguishable from neighboring cells. However, in recent years a significant body of work has begun to characterize the skin epithelial stem cells, both in tissue culture and in mouse and human skin. Some epithelial cells cultured from skin exhibit prodigious proliferative potential; in fact, for >20 years now, cultured human skin has been used as a source of new skin to engraft onto damaged areas of burn patients, representing one of the first therapeutic uses of stem cells. Cell fate choices, including both self-renewal and differentiation, are crucial biological features of stem cells that are still poorly understood. Skin epithelial stem cells represent a ripe target for research into the fundamental mechanisms underlying these important processes. PMID:12913119

  8. Human vomeronasal epithelium development: An immunohistochemical overview.

    PubMed

    Dénes, Lóránd; Pap, Zsuzsanna; Szántó, Annamária; Gergely, István; Pop, Tudor Sorin

    2015-06-01

    The vomeronasal organ (VNO) is the receptor structure of the vomeronasal system (VNS) in vertebrates. It is found bilaterally in the submucosa of the inferior part of the nasal septum. There are ongoing controversies regarding the functionality of this organ in humans. In this study we propose the immunohistochemical evaluation of changes in components of the human vomeronasal epithelium during foetal development. We used 45 foetuses of different age, which were included in three age groups. After VNO identification immunohistochemical reactions were performed using primary antibodies against the following: neuron specific enolase, calretinin, neurofilament, chromogranin, synaptophysin, cytokeratin 7, pan-cytokeratin and S100 protein. Digital slides were obtained and following colorimetric segmentation, surface area measurements were performed. The VNO was found in less than half of the studied specimens (42.2%). Neuron specific enolase and calretinin immunoexpression showed a decreasing trend with foetal age, while the other neural/neuroendocrine markers were negative in all specimens. Cytokeratin 7 expression increased with age, while Pan-Ctk had no significant variations. S100 protein immunoexpression also decreased around the VNO. The results of the present work uphold the theory of regression of the neuroepithelium that is present during initial stages of foetal development.

  9. Glucose metabolism in rat retinal pigment epithelium.

    PubMed

    Coffe, Víctor; Carbajal, Raymundo C; Salceda, Rocío

    2006-01-01

    The retinal pigment epithelium (RPE) is the major transport pathway for exchange of metabolites and ions between choroidal blood supply and the neural retina. To gain insight into the mechanisms controlling glucose metabolism in RPE and its possible relationship to retinopathy, we studied the influence of different glucose concentrations on glycogen and lactate levels and CO(2) production in RPE from normal and streptozotocin-treated diabetic rats. Incubation of normal RPE in the absence of glucose caused a decrease in lactate production and glycogen content. In normal RPE, increasing glucose concentrations from 5.6 mM to 30 mM caused a four-fold increase in glucose accumulation and CO(2) yield, as well as reduction in lactate and glycogen production. In RPE from diabetic rats glucose accumulation did not increase in the presence of high glucose substrate, but it showed a four- and a seven-fold increase in CO(2) production through the mitochondrial and pentose phosphate pathways, respectively. We found high glycogen levels in RPE which can be used as an energy reserve for RPE itself and/or neural retina. Findings further show that the RPE possesses a high oxidative capacity. The large increase in glucose shunting to the pentose phosphate pathway in diabetic retina exposed to high glucose suggests a need for reducing capacity, consistent with increased oxidative stress. PMID:16475003

  10. Cell Jamming in the Airway Epithelium.

    PubMed

    Park, Jin-Ah; Fredberg, Jeffrey J

    2016-03-01

    Hallmarks of asthma include chronic airway inflammation, progressive airway remodeling, and airway hyperresponsiveness. The initiation and perpetuation of these processes are attributable at least in part to critical events within the airway epithelium, but the underlying mechanisms remain poorly understood. New evidence now suggests that epithelial cells derived from donors without asthma versus donors with asthma, even in the absence of inflammatory cells or mediators, express modes of collective migration that innately differ not only in the amount of migration but also in the kind of migration. The maturing cell layer tends to undergo a transition from a hypermobile, fluid-like, unjammed phase in which cells readily rearrange, exchange places, and flow, to a quiescent, solid-like, jammed phase in which cells become virtually frozen in place. Moreover, the unjammed phase defines a phenotype that can be perpetuated by the compressive stresses caused by bronchospasm. Importantly, in cells derived from donors with asthma versus donors without asthma, this jamming transition becomes substantially delayed, thus suggesting an immature or dysmature epithelial phenotype in asthma. PMID:27027955

  11. Changes in the adult vertebrate auditory sensory epithelium after trauma.

    PubMed

    Oesterle, Elizabeth C

    2013-03-01

    Auditory hair cells transduce sound vibrations into membrane potential changes, ultimately leading to changes in neuronal firing and sound perception. This review provides an overview of the characteristics and repair capabilities of traumatized auditory sensory epithelium in the adult vertebrate ear. Injured mammalian auditory epithelium repairs itself by forming permanent scars but is unable to regenerate replacement hair cells. In contrast, injured non-mammalian vertebrate ear generates replacement hair cells to restore hearing functions. Non-sensory support cells within the auditory epithelium play key roles in the repair processes.

  12. [Ovarian surface epithelium and its histogenic relation to ovarian cancer].

    PubMed

    Dietl, J; Buchholz, F; Stoll, P

    1986-09-01

    Approximately 80 to 90 per cent of adult ovarian cancers are assumed to originate from ovarian surface cells. A series of morphological and biochemical studies has been recently conducted to test this. The ovarian surface epithelium shows permanent morphological changes such as crypts, inclusion cysts, villous processes and different forms of müllerian epithelium. The unique nature of ovarian surface changes and their abrupt disappearance in immediately adjacent mesothelia suggest that local factors may play an important part in modifying the growth and morphogenesis of the epithelium of the ovarian surface. Whether these endogenous and/or exogenous factors may also induce surface neoplasia is a moot point.

  13. Intracellular transport of nanocarriers across the intestinal epithelium.

    PubMed

    Fan, Weiwei; Xia, Dengning; Zhu, Quanlei; Hu, Lei; Gan, Yong

    2016-05-01

    The intestinal epithelium is the main barrier restricting the oral delivery of low-permeability drugs. Over recent years, numerous nanocarriers have been designed to improve the efficiency of oral drug delivery. However, the intracellular processes determining the transport of nanocarriers across the intestinal epithelium remain elusive, and only limited enhancement of the oral bioavailability of drugs has been achieved. Here, we review the processes involved in nanocarrier trafficking across the intestinal epithelium, including apical endocytosis, intracellular transport, and basolateral exocytosis. Understanding the complex intracellular processes of nanocarrier trafficking is particularly essential for the rational design of oral drug delivery systems. PMID:27094490

  14. Ultrastructural study of grafted autologous cultured human epithelium.

    PubMed

    Aihara, M

    1989-01-01

    An electron microscopical study of grafted autologous cultured human epithelium is presented. Biopsy samples were collected from four patients with full thickness burns at 9 days, 6 weeks and 5-21 months after grafting of the cultured epithelium. By the sixth week after transplantation, grafted cultured epithelial sheets had developed to consist of 10 to 20 layers of cells and the epithelium showed distinct basal, spinous, granular and horny layers, and a patchy basement membrane had formed. Langerhans cells and melanocytes were identifiable. From 5 months onwards flat basal cells became oval, and oval keratohyalin granules in the keratinocytes also assumed a normal irregular shape. Membrane-coating granules in the keratinocytes increased in number. The fine structures of desmosomes also showed a normal mature appearance. Furthermore, complete extension of the basement membrane could be observed. The maturation of cultured human epithelium is complete by 5 months after grafting.

  15. Expression of Ki-67 in normal oral epithelium, leukoplakic oral epithelium and oral squamous cell carcinoma

    PubMed Central

    Birajdar, Smita Shrishail; Radhika, MB; Paremala, K; Sudhakara, M; Soumya, M; Gadivan, Mohsin

    2014-01-01

    Aims and Objective: To demonstrate the presence, location and pattern of cell proliferation in different histological grades of oral epithelial dysplasia (OED), oral squamous cell carcinoma (OSCC) and normal oral epithelium (NOE) using an antibody directed against the Ki-67 antigen and its intensity of staining evaluated respectively. Materials and Methods: A total number of 100 archival paraffin embedded blocks obtained from Department of Oral and Maxillofacial Pathology were studied. The case details were retrieved which consisted of histopathologically diagnosed cases of OSCC (n = 20), low risk OED (n = 30), high risk OED (n = 30) and normal appearing mucosa (n = 20) were taken as standard for comparison. Ki-67 immunostaining was detected. Ki-67 positive cells were counted in the five random high power fields in each case. Results: Ki-67 labeling Index (LI) was restricted to the basal and parabasal layers of the normal oral epithelium irrespective of age, sex and site whereas it was seen in the basal, suprabasal and spinous layers in OED. Ki-67 LI is increased in high risk cases than the low risk cases of OED. Ki-67 positive cells in OSCC were located in the periphery of the tumor nests than the center, where frequent mitoses were observed. Conclusion: The architectural alteration evaluated by Ki-67 antibody in proliferating cell distribution in the layers of epithelial dysplasias may provide useful information to evaluate the grading of OED. Ki-67 LI increased in high risk cases than low risk cases of OED. This study showed that over expression of Ki-67 antigen between well-differentiated and poorly differentiated OSCC was in accordance with histologic grade of malignancy but not in accordance with moderately differentiated OSCC. PMID:25328294

  16. Histomorphological changes in the oviduct epithelium of the rabbit during early pregnancy.

    PubMed

    Anzaldúa, S R; Camacho-Arroyo, I; Cerbón, M A

    2002-10-01

    In this study, we determined the histomorphological changes in different regions of the oviduct (fimbriae, infundibulum, ampullae and isthmus) during early pregnancy (days 1-4) of the rabbit. It was observed that the number of secretory cells (PAS-positive cells) diminished in the fimbriae during the first 4 days of pregnancy with the corresponding increase in the number of non-secretory cells (PAS-negative cells). In contrast, there was an increase in the number of PAS-positive cells in the isthmus during early pregnancy. In both the infundibulum and the ampullae the number of PAS-positive cells was increased on day 3. A significant decrease in the height of the epithelium was observed in the fimbriae during early pregnancy. On the contrary, a significant increase in this parameter was observed in the isthmus during the first 3 days of pregnancy. A slight decrease in the height of the epithelium was observed in the infundibulum on day 4 of pregnancy, while in the ampullae it was significantly increased on days 1 and 3. The overall results indicate that during early pregnancy there is a selective modification in the histomorphological characteristics of the different regions of the rabbit oviduct.

  17. Developmental origin of the posterior pigmented epithelium of iris.

    PubMed

    Wang, Xiaobing; Xiong, Kai; Lu, Lei; Gu, Dandan; Wang, Songtao; Chen, Jing; Xiao, Honglei; Zhou, Guomin

    2015-03-01

    Iris epithelium is a double-layered pigmented cuboidal epithelium. According to the current model, the neural retina and the posterior iris pigment epithelium (IPE) are derived from the inner wall of the optic cup, while the retinal pigment epithelium (RPE) and the anterior IPE are derived from the outer wall of the optic cup during development. Our current study shows evidence, contradicting this model of fetal iris development. We demonstrate that human fetal iris expression patterns of Otx2 and Mitf transcription factors are similar, while the expressions of Otx2 and Sox2 are complementary. Furthermore, IPE and RPE exhibit identical morphologic development during the early embryonic period. Our results suggest that the outer layer of the optic cup forms two layers of the iris epithelium, and the posterior IPE is the inward-curling anterior rim of the outer layer of the optic cup. These findings provide a reasonable explanation of how IPE cells can be used as an appropriate substitute for RPE cells.

  18. Ultrastructure of free-ending nerve fibres in oesophageal epithelium.

    PubMed Central

    Robles-Chillida, E M; Rodrigo, J; Mayo, I; Arnedo, A; Gómez, A

    1981-01-01

    For the first time, at the ultrastructural level, the existence of free-ending, intraepithelial nerve fibres has been demonstrated in the oesophagus wall of adult cats and monkeys. Their form, the way they penetrate the epithelium, their location within the epithelium and their relationships with neighbouring cells have been established. A sensory function is suggested for this type of ending. Images Figs. 1-4 Figs. 5-6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Figs. 14-15 Figs. 16-17 PMID:7333951

  19. The ionic components of normal human oesophageal epithelium.

    PubMed

    Hopwood, D; Milne, G; Curtis, M; Nicholson, G

    1979-11-01

    The distribution of cations and anions in normal human oesophageal epithelium has been investigated with the pyroantimonate and silver-osmium tetroxide techniques. There is a discontinuous distribution of both ions in the intercellular space. The ions are associated with various organelles, as has already been described in the literature. Specifically, in the oesophageal epithelium, there are a few deposits of pyroantimonate and occasional silver in the membrane coating granules, but here is no apparent relationship of either ion with the tonofilaments or glycogen particles. The superficial cells are leaky and contain fewer ions than the deeper functional layer cells.

  20. The permeability of a keratinizing squamous epithelium in culture.

    PubMed

    Squier, C A; Fejerskov, O; Jepsen, A

    1978-05-01

    Horseradish peroxidase or lanthanum was applied to the surface of keratinized oral epithelium growing in tissue culture and the extent of penetration of these substances examined with the electron microscope. Both tracer substances penetrated between the superficial keratinized squames of the tissue, the lanthanum reaching the basal cell layer and the peroxidase diffusing to within 3--8 cells of the basal layer. The permeability of the keratinized layer in this epithelium is in contrast to the situation in vivo where an intercellular barrier is found in the superficial layer. This difference might be related to the absence of membrane-coating granules from the tissue maintained in culture.

  1. Cigarette smoke inhibition of ion transport in canine tracheal epithelium

    SciTech Connect

    Welsh, M.J.

    1983-06-01

    To determine the effect of cigarette smoke on airway epithelial ion transport, the electrical properties and transepithelial Na and Cl fluxes were measured in canine tracheal epithelium. In vivo, the inhalation of the smoke from one cigarette acutely and reversibly decreased the electrical potential difference across the tracheal epithelium. In vitro, exposure of the mucosal surface of the epithelium to cigarette smoke decreased the short circuit current and transepithelial resistance. The decrease in short circuit current was due to an inhibition of the rate of Cl secretion with minimal effect on the rate of Na absorption. The effect of cigarette smoke was reversible, was not observed upon exposure of the submucosal surface to smoke, and was most pronounced when secretion was stimulated. The particulate phase of smoke was largely responsible for the inhibitory effect, since filtering the smoke minimized the effect. The effect of cigarette smoke was not prevented by addition of antioxidants to the bathing solutions, suggesting that the inhibition of Cl secretion cannot be entirely attributed to an oxidant mechanism. These results indicate that cigarette smoke acutely inhibits active ion transport by tracheal epithelium, both in vivo and in vitro. This effect may explain, in part, both the abnormal mucociliary clearance and the airway disease observed in cigarette smokers.

  2. Examination of the reticular epithelium of the bovine pharyngeal tonsil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The nasopharyngeal tonsil (adenoid), located at the posterior of the nasopharynx is ideally positioned to sample antigens entering through the nasal cavity or oral cavity. Entering antigens will first contact tonsilar epithelium. To better understand the cellular composition of this important epithe...

  3. Quantum Dot Distribution in the Olfactory Epithelium After Nasal Delivery

    NASA Astrophysics Data System (ADS)

    Garzotto, D.; De Marchis, S.

    2010-10-01

    Nanoparticles are used in a wide range of human applications from industrial to bio-medical fields. However, the unique characteristics of nanoparticles, such as the small size, large surface area per mass and high reactivity raises great concern on the adverse effects of these particles on ecological systems and human health. There are several pioneer studies reporting translocation of inhaled particulates to the brain through a potential neuronal uptake mediated by the olfactory nerve (1, 2, 3). However, no direct evidences have been presented up to now on the pathway followed by the nanoparticles from the nose to the brain. In addition to a neuronal pathway, nanoparticles could gain access to the central nervous system through extracellular pathways (perineuronal, perivascular and cerebrospinal fluid paths). In the present study we investigate the localization of intranasally delivered fluorescent nanoparticles in the olfactory epithelium. To this purpose we used quantum dots (QDs), a model of innovative fluorescent semiconductor nanocrystals commonly used in cell and animal biology (4). Intranasal treatments with QDs were performed acutely on adult CD1 mice. The olfactory epithelium was collected and analysed by confocal microscopy at different survival time after treatment. Data obtained indicate that the neuronal components of the olfactory epithelium are not preferentially involved in QDs uptake, thus suggesting nanoparticles can cross the olfactory epithelium through extracellular pathways.

  4. Alterations to the bull sperm surface proteins that bind sperm to oviductal epithelium.

    PubMed

    Hung, Pei-hsuan; Suarez, Susan S

    2012-10-01

    Three Binder of SPerm proteins (BSP1, BSP3, BSP5) are secreted by bovine seminal vesicles into seminal plasma and adsorbed onto sperm. When sperm inseminated into the female reach the oviduct, the BSP proteins bind them to its epithelial lining, forming a sperm storage reservoir. Previously, we reported that binding of capacitated sperm to oviductal epithelium in vitro is lower than that of uncapacitated sperm and we proposed that reduced binding was due to loss of BSP proteins during capacitation. Because of differences in amino acid sequences, we predicted that each BSP would respond differently to capacitating conditions. To test whether all three BSP proteins were lost from sperm during capacitation and whether the kinetics of loss differed among the three BSP proteins, ejaculated bull sperm were incubated under various capacitating conditions, and then the amounts of BSP proteins remaining on the sperm were assayed by Western blotting. Capacitation was assayed by analysis of protein tyrosine phosphorylation. While loss of BSP1 was not detected, most of the BSP5 was lost from sperm during incubation in TALP medium, even without addition of the capacitation enhancers heparin and dbcAMP-IBMX. Surprisingly, a smaller molecular mass was detected by anti-BSP3 antibodies in extracts of incubated sperm. Its identity was confirmed as BSP3 by mass spectrometry, indicating that BSP3 undergoes modification on the sperm surface. These changes in the composition of BSP proteins on sperm could play a role in releasing sperm from the storage reservoir by modifying sperm interactions with the oviductal epithelium.

  5. Orthogonal arrays in normal and injured respiratory airway epithelium.

    PubMed

    Gordon, R E

    1985-02-01

    Orthogonal arrays are found on plasma membranes of glial cells, in the central nervous system, on muscle plasma membranes at neuromuscular junctions, and on a variety of epithelial cells. These structures have been correlated with ion flux. With the aid of freeze fracture technique, orthogonal particle arrays were found on plasma membranes on airway epithelial cells of rats and hamsters. They have been found in abundance at the base of secretory cells throughout normal airway epithelium. These structures were found to increase in number during regeneration in response to injury and they were found in great numbers on plasma membranes of all airway cells in response to acute and chronic NO2 exposure. The lateral and basal plasma membranes of the respiratory epithelium are a new source for studying orthogonal arrays. The normal number and distribution of these arrays can be perturbed in response to mechanical and chemical injury. PMID:3968185

  6. [Hormone-mediated reactions in the endosalpinx epithelium].

    PubMed

    Glukhovets, B I; Ukhov, Iu I; Lebedev, S S; Plastun, G A; Bulaeva, V P

    1983-07-01

    The epithelium of normal uterine tubes resected in 38 young women of the child-bearing age during the periods of the maximal physiological fluctuations of the ovarian steroid hormones levels has been studied. The correlative dependence between the morphometrical data and the results of quanitative biochemical analysis of the estrogen excretion has been investigated. The morphometric method reliably reflects the hormone-dependent variabilities of the oviduct epithelium and makes it possible to perform an objective morphological evaluation of the ovarian functional activity. The height and specific density of cells in the epithelial layer, portion of the aciliary cells and nuclear volume of the ciliary cells are the most important for diagnosis as compared to the excretory level of the estrogenic hormones. PMID:6625907

  7. Hydrodynamics of stratified epithelium: Steady state and linearized dynamics

    NASA Astrophysics Data System (ADS)

    Yeh, Wei-Ting; Chen, Hsuan-Yi

    2016-05-01

    A theoretical model for stratified epithelium is presented. The viscoelastic properties of the tissue are assumed to be dependent on the spatial distribution of proliferative and differentiated cells. Based on this assumption, a hydrodynamic description of tissue dynamics at the long-wavelength, long-time limit is developed, and the analysis reveals important insights into the dynamics of an epithelium close to its steady state. When the proliferative cells occupy a thin region close to the basal membrane, the relaxation rate towards the steady state is enhanced by cell division and cell apoptosis. On the other hand, when the region where proliferative cells reside becomes sufficiently thick, a flow induced by cell apoptosis close to the apical surface enhances small perturbations. This destabilizing mechanism is general for continuous self-renewal multilayered tissues; it could be related to the origin of certain tissue morphology, tumor growth, and the development pattern.

  8. The dorsal lingual epithelium of Rhinoclemmys pulcherrima incisa (Chelonia, Cryptodira).

    PubMed

    Josef Beisser, Christian; Lemell, Patrick; Weisgram, Josef

    2004-03-01

    This study employed light microscopic (LM), scanning electron microscopic (SEM), and transmission electron microscopic (TEM) methods to provide detailed morphological information on the histological and ultrastructural features of the dorsal tongue epithelium of Rhinoclemmys pulcherrima incisa. SEM revealed columnar papillae laterally, as well as papillae, which tend to have a ridge-like appearance in the center of the tongue. LM and TEM showed three different zones of lingual epithelium: a stratified apical area with serous cells at the top of the papillae, a stratified lateral area with both serous and mucus cells, and an unstratified glandular area consisting of distinct glandular ducts with mucus cells. Comparison with morphological data from other turtles shows that the lingual epithelial structure in R. p. incisa is in accordance with that observed for other generalized omnivores which prefer a terrestrial lifestyle, thus matching the ecological information about this species.

  9. Gallbladder epithelium as a niche for chronic Salmonella carriage.

    PubMed

    Gonzalez-Escobedo, Geoffrey; Gunn, John S

    2013-08-01

    Although typhoid fever has been intensively studied, chronic typhoid carriage still represents a problem for the transmission and persistence of the disease in areas of endemicity. This chronic state is highly associated with the presence of gallstones in the gallbladder of infected carriers upon which Salmonella can form robust biofilms. However, we hypothesize that in addition to gallstones, the gallbladder epithelium aids in the establishment/maintenance of chronic carriage. In this work, we present evidence of the role of the gallbladder epithelium in chronic carriage by a mechanism involving invasion, intracellular persistence, and biofilm formation. Salmonella was able to adhere to and invade polarized gallbladder epithelial cells apically in the absence and presence of bile in a Salmonella pathogenicity island 1 (SPI-1)-dependent manner. Intracellular replication of Salmonella was also evident at 12 and 24 h postinvasion. A flowthrough system revealed that Salmonella is able to adhere to and form extensive bacterial foci on gallbladder epithelial cells as early as 12 h postinoculation. In vivo experiments using a chronic mouse model of typhoid carriage showed invasion and damage of the gallbladder epithelium and lamina propria up to 2 months after Salmonella infection, with an abundant presence of macrophages, a relative absence of neutrophils, and extrusion of infected epithelial cells. Additionally, microcolonies of Salmonella cells were evident on the surface of the mouse gallbladder epithelia up to 21 days postinfection. These data reveal a second potential mechanism, intracellular persistence and/or bacterial aggregation in/on the gallbladder epithelium with luminal cell extrusion, for Salmonella maintenance in the gallbladder.

  10. Intraocular involvement with subretinal pigment epithelium infiltrates by mycosis fungoides.

    PubMed Central

    Erny, B. C.; Egbert, P. R.; Peat, I. M.; Shorrock, K.; Rosenthal, A. R.

    1991-01-01

    We report a case of intraocular mycosis fungoides in a 48-year-old man. The patient presented with decreased visual acuity, white subretinal lesions, and vitritis. Post-mortem histopathology revealed malignant T cell infiltrates consistent with mycosis fungoides in the retina, vitreous, and between the retinal pigment epithelium (RPE) and Bruch's membrane Focal atrophy of the RPE, along with the sub-RPE infiltrates, correlated with the clinically visible fundus lesions. Images PMID:1751471

  11. Dietary nitrogen reduction enhances urea transport across goat rumen epithelium.

    PubMed

    Muscher, A S; Schröder, B; Breves, G; Huber, K

    2010-10-01

    Ruminants are very capable of adapting their N homeostasis to a reduced dietary N intake. However, the limits of this physiological adaptation are still unknown. The aim of the present study was to determine the quantity of dietary N intake at which the needs of the animal are still satisfied. A study was performed in young White Saanen goats under conditions of dietary N reduction. Different semisynthetic diets with 19 to 7% CP were fed. Urea transport rates across the rumen epithelium from the blood into the ruminal fluid were quantified by Ussing chamber experiments. Reduced N intake increased urea transport rates across the mucosa, which could be inhibited by phloretin. The role of parietal urease in driving urea transfer across the epithelium was negligible because its activity was inhibited by antibiotics during in vitro incubations of the epithelium. Concentrations of ammonia in the ruminal fluid were decreased by reducing dietary N intake, accompanied by diminished urease activity at the smallest dietary N intake. Over the range of plasma urea concentrations observed in the different feeding groups, salivary urea concentrations were 73% of plasma urea concentrations. By plotting plasma urea concentrations against serosal to mucosal urea flux rates, a threshold at 1.75 mmol of urea/L of plasma could be assessed, below which urea flux was strongly increased. This indicates that rumen urea transfer could be stimulated by decreased plasma urea concentrations via unknown mechanisms. The physiological relevance of this adaptation of the rumen epithelium is that it is considered a central mechanism in the N homeostasis of growing goats under reduced N intake.

  12. The oxidant role of 4-hydroxynonenal in corneal epithelium.

    PubMed

    Chen, Longlong; Zong, Rongrong; Zhou, Jing; Ge, Lianping; Zhou, Tong; Ma, Jian-xing; Liu, Zuguo; Zhou, Yueping

    2015-01-01

    4-Hydroxynonenal (4-HNE or HNE) is a main endogenous product of cellular lipid peroxidation in tissues and is reported to play pathogenic roles in eye diseases. Here we investigated the association between 4-HNE and oxidative stress in the corneal epithelium. 4-HNE suppressed the cell viability of human corneal epithelial cells (HCE) in a concentration dependent manner. 4-HNE significantly increased the level of 3-Nitrotyrosine (3-NT), a marker of oxidative stress, in HCE cells and corneal epithelium of rats by immunofluorescent staining and Western blot analysis. To its underlying mechanistic on ROS system, 4-HNE elevated the ROS generation enzyme NADPH oxidase 4 (NOX4) and induced the activation of NF-E2-related factor-2 (NRF2) and its downstream effectors: NAD(P)H dehydrogenase (quinone 1) (NQO1) and glutathione S-transferase P (GSTP). Furthermore, N-acetylcysteine (NAC), an antioxidant and ROS scavenger, antagonized the inhibitory and oxidant effects of 4-HNE on the corneal epithelial cells. In conclusion, 4-HNE plays an oxidant role in the corneal epithelium and this work provides a new strategy for the pathogenesis and treatment of corneal diseases.

  13. Zinc uptake in vitro by human retinal pigment epithelium

    SciTech Connect

    Newsome, D.A.; Rothman, R.J.

    1987-11-01

    Zinc, an essential trace element, is present in unusually high concentrations in the chorioretinal complex relative to most other tissues. Because little has been known about the interactions between the retinal pigment epithelium and free or protein-associated zinc, we studied /sup 65/Zn uptake by human retinal pigment epithelium in vitro. When monolayers were exposed to differing concentrations from 0 to 30 microM /sup 65/Zn in Dulbecco's modified Eagle's medium with 5.4 gm/l glucose at 37 degrees C and 4 degrees C, we observed a temperature-dependent saturable accumulation of the radiolabel. With 15 microM /sup 65/Zn, we saw a biphasic pattern of uptake with a rapid first phase and a slower second phase over 120 min. Uptake of /sup 65/Zn was inhibited by iodacetate and cold, and reduced approximately 50% by the addition of 2% albumin to the labelling medium. Neither ouabain nor 2-deoxyglucose inhibited uptake. Cells previously exposed to /sup 65/Zn retained approximately 70% of accumulated /sup 65/Zn 60 min after being changed to radiolabel-free medium. Following removal of cells from the extracellular matrix adherent to the dish bottom, a variable amount of nonspecific binding of /sup 65/Zn to the residual matrix was demonstrated. These observations are consistent with a facilitated type of transport and demonstrate the ability of human retinal pigment epithelium in vitro to accumulate and retain zinc.

  14. Integrin Beta 1 Suppresses Multilayering of a Simple Epithelium

    PubMed Central

    Chen, Jichao; Krasnow, Mark A.

    2012-01-01

    Epithelia are classified as either simple, a single cell layer thick, or stratified (multilayered). Stratified epithelia arise from simple epithelia during development, and transcription factor p63 functions as a key positive regulator of epidermal stratification. Here we show that deletion of integrin beta 1 (Itgb1) in the developing mouse airway epithelium abrogates airway branching and converts this monolayer epithelium into a multilayer epithelium with more than 10 extra layers. Mutant lung epithelial cells change mitotic spindle orientation to seed outer layers, and cells in different layers become molecularly and functionally distinct, hallmarks of normal stratification. However, mutant lung epithelial cells do not activate p63 and do not switch to the stratified keratin profile of epidermal cells. These data, together with previous data implicating Itgb1 in regulation of epidermal stratification, suggest that the simple-versus-stratified developmental decision may involve not only stratification inducers like p63 but suppressors like Itgb1 that prevent simple epithelia from inappropriately activating key steps in the stratification program. PMID:23285215

  15. In vitro biology of corneal epithelium and endothelium.

    PubMed Central

    Yanoff, M

    1975-01-01

    Four main areas are explored: (1) the proper culture medium for corneal tissue; (2) the effect of serum on in vitro tissue growth; (3) the in vitro interrelationships between corneal epithelium and endothelium; and (4) the biology of cultures of whole corneas (organ cultures). Modified Eagle's minimal essential medium (MEM) proved to be an excellent culture fluid. Corneal tissue could be grown in MEM without serum or clot, thus providing a defined culture medium. The in vitro biology of outgrowths of multilayered corneal epithelium and monolayered corneal endothelium are discussed. Contact inhibition between epithelium and endothelium is demonstrated in whole corneal (organ) cultures. Images FIGURE 5 A FIGURE 5 B FIGURE 10 A FIGURE 10 B FIGURE 1 A FIGURE 1 B FIGURE 1 C FIGURE 2 A FIGURE 2 B FIGURE 3 A FIGURE 3 B FIGURE 4 A FIGURE 4 B FIGURE 6 A FIGURE 6 B FIGURE 7 A FIGURE 7 B FIGURE 8 A FIGURE 8 B FIGURE 9 A FIGURE 9 B FIGURE 11 A FIGURE 11 B FIGURE 12 A FIGURE 12 B FIGURE 12 C FIGURE 13 FIGURE 14 A FIGURE 14 B FIGURE 15 A FIGURE 15 B FIGURE 16 A FIGURE 16 B FIGURE 17 A FIGURE 17 B FIGURE 17 C FIGURE 18 A FIGURE 18 B PMID:1246815

  16. Mucosal adenosine stimulates chloride secretion in canine tracheal epithelium

    SciTech Connect

    Pratt, A.D.; Clancy, G.; Welsh, M.J.

    1986-08-01

    Adenosine is a local regulator of a variety of physiological functions in many tissues and has been observed to stimulate secretion in several Cl-secreting epithelia. In canine tracheal epithelium the authors found that adenosine stimulates Cl secretion from both the mucosal and submucosal surfaces. Addition of adenosine, or its analogue 2-chloroadenosine, to the mucosal surface potently stimulated Cl secretion with no effect on the rate of Na absorption. Stimulation resulted from an interaction of adenosine with adenosine receptors, because it was blocked by the adenosine receptor blocker, 8-phenyltheophylline. The adenosine receptor was a stimulatory receptor as judged by the rank-order potency of adenosine and its analogues and by the increase in cellular adenosine 3',5'-cyclic monophosphate levels produced by 2-chloroadenosine. Adenosine also stimulated Cl secretion when it was added to the submucosal surface, although the maximal increase in secretion was less and it was much less potent. The observation that mucosal 8-phenyletheophylline blocked the effect of submucosal 2-chloroadenosine, whereas submucosal 8-phenyltheophylline did not prevent a response to mucosal or submucosal 2-chloroadenosine, suggests that adenosine receptors are located on the mucosal surface. Thus submucosal adenosine may stimulate secretion by crossing the epithelium and interacting with receptors located on the mucosal surface. Because adenosine can be released from mast cells located in the airway lumen in response to inhaled material, and because adenosine stimulated secretion from the mucosal surface, it may be in a unique position to control the epithelium on a regional level.

  17. Effect of carbonated drinks on wound healing of oral epithelium

    PubMed Central

    Fahim, Ayesha; Ilyas, Muhammad Sharjeel; Jafari, Fahim Haider; Farzana, Fauzia

    2015-01-01

    Background Carbonated drinks are the second most consumed non-alcoholic beverages in the world after tea. The effects of these drinks on hard tissues and vital organs of the body have been proved beyond doubt. This study, however, explains the effect of these drinks on wound healing of oral epithelium. Methods Thirty-six male Wistar rats were considered for the study. A circular wound of 3.0 mm was created on the buccal mucosa of all animals and they were divided into two groups. Animals in group 1 were fed with chow pellet and water, while those in group 2 were fed with a commercially available carbonated drink instead of water. Six animals from each group were euthanized at 0, 7, and 21 days. Wound site was histologically assessed for differences in thickness and characteristics of the regenerating epithelium between two groups. Results There was a marked difference in the healing pattern between the two groups. Animals in group 1 showed a normal healing pattern at the end of day 21. In the group 2, the regenerated epithelium showed hyperplasia and hyperkeratosis along with acanthosis at the end of the experiment with a subsequent delayed inflammatory reaction at day 21. Conclusion Consumption of carbonated drinks can disrupt oral wound healing. The contents in carbonated drinks have a proinflammatory action on the soft tissue. Results suggest that epithelial changes seen in experimental group 2 could be a result of constant irritation by the acidic and fizzy nature of carbonated drinks. PMID:26937370

  18. The pocket epithelium: a light- and electronmicroscopic study.

    PubMed

    Müller-Glauser, W; Schroeder, H E

    1982-03-01

    The POCKET epithelium is important for the pathogenesis of gingivitis and periodontitis. However, this epithelial variant has never been adequately described. The bioptic material with supraalveolar pockets originated from previous studies in which cotton floss ligatures were placed around the crowns of premolars in eight dogs. After periods of 4 to 21 days or up to 5 months, block biopsies comprising dental and gingival tissues were taken on the buccal side. The tissues were processed for light- and electron microscopic examination. The observations revealed that the pocket epithelium (1) does not attach to the tooth, (2) forms irregular ridges and, over connective tissue papillae, thin coverings which occasionally ulcerate, (3) consists of cells only some of which show a tendency to differentiate, (4) presents a basal lamina complex with discontinuities and multiplications, and (5) is infiltrated mainly by lymphocytes, T- and B-blasts and plasma cells, and is transmigrated by neutrophilic granulocytes. It is concluded that the mosaic-like structure of the pocket epithelium reflects the heterogeneity of the adjacent plaque, that this structure together with the absence of membrane coating granules is the basis for an extremely high permeability, and that epithelial ridges may conduct and collect foreign substances which thereby become more easily recognizable for leukocytes.

  19. Alterations in the mantle epithelium during transition from hatching gland to adhesive organ of Idiosepius pygmaeus (Mollusca, Cephalopoda).

    PubMed

    Cyran, Norbert; Klepal, Waltraud; Städler, Yannick; Schönenberger, Jürg; von Byern, Janek

    2015-02-01

    Epithelial gland systems play an important role in marine molluscs in fabricating lubricants, repellents, fragrances, adhesives or enzymes. In cephalopods the typically single layered epithelium provides a highly dynamic variability and affords a rapid rebuilding of gland cells. While the digestive hatching gland (also named Hoyle organ) is obligatory for most cephalopods, only four genera (Nautilus, Sepia, Euprymna and Idiosepius) produce adhesive secretions by means of glandular cells in an adhesive area on the mantle or tentacles. In Idiosepius this adhesive organ is restricted to the posterior part of the fin region on the dorsal mantle side and well developed in the adult stage. Two gland cell types could be distinguished, which produce different contents of the adhesive. During the embryonic development the same body area is occupied by the temporary hatching gland. The question arises, in which way the hatching gland degrades and is replaced by the adhesive gland. Ultrastructural analyses as well as computer tomography scans were performed to monitor the successive post hatching transformation in the mantle epithelium from hatching gland degradation to the formation of the adhesive organ. According to our investigations the hatching gland cells degrade within about 1 day after hatching by a type of programmed cell death and leave behind a temporary cellular gap in this area. First glandular cells of the adhesive gland arise 7 days after hatching and proceed evenly over the posterior mantle epithelium. In contrast, the accompanying reduction of a part of the dorsal mantle musculature is already established before hatching. The results demonstrate a distinct independence between the two gland systems and illustrate the early development of the adhesive organ as well as the corresponding modifications within the mantle.

  20. Ion transport across an isolated preparation of sheep rumen epithelium.

    PubMed

    Ferreira, H G; Harrison, F A; Keynes, R D; Zurich, L

    1972-04-01

    1. The fluxes of isotopically labelled sodium, potassium and chloride passing in each direction across isolated sheets of rumen epithelium from the sheep have been measured under short-circuit conditions.2. With both sides of the epithelium bathed in chloride Ringer the mean sodium fluxes were 2.85 mumole/cm(2).hr from rumen to blood and 1.28 mumole/cm(2).hr in the reverse direction. In sulphate Ringer the sodium fluxes were 1.64 mumole/cm(2).hr from rumen to blood and 0.54 mumole/cm(2).hr from blood to rumen.3. In chloride Ringer the mean potassium fluxes were 0.18 mumole/cm(2).hr from rumen to blood and 0.54 mumole/cm(2).hr from blood to rumen. In sulphate Ringer the potassium fluxes were 0.07 mumole/cm(2).hr from rumen to blood and 0.35 mumole/cm(2).hr from blood to rumen.4. In chloride Ringer the mean chloride fluxes were 4.89 mumole/cm(2).hr from rumen to blood and 3.78 mumole/cm(2).hr from blood to rumen.5. In chloride Ringer the mean value of the short-circuit current was 13 muA/cm(2), corresponding to a flux of 0.49 muequiv/cm(2).hr. When sulphate was substituted for chloride, the short-circuit current was increased by about 40%, and the net flux of sodium from rumen to blood fell by 30%.6. Neither the sodium nor the chloride fluxes changed significantly when the epithelium was temporarily open-circuited.

  1. Lack of Dystrophin Affects Bronchial Epithelium in mdx Mice.

    PubMed

    Morici, Giuseppe; Rappa, Francesca; Cappello, Francesco; Pace, Elisabetta; Pace, Andrea; Mudò, Giuseppa; Crescimanno, Grazia; Belluardo, Natale; Bonsignore, Maria R

    2016-10-01

    Mild exercise training may positively affect the course of Duchenne Muscular Dystrophy (DMD). Training causes mild bronchial epithelial injury in both humans and mice, but no study assessed the effects of exercise in mdx mice, a well known model of DMD. The airway epithelium was examined in mdx (C57BL/10ScSn-Dmdmdx) mice, and in wild type (WT, C57BL/10ScSc) mice either under sedentary conditions (mdx-SD, WT-SD) or during mild exercise training (mdx-EX, WT-EX). At baseline, and after 30 and 45 days of training (5 d/wk for 6 weeks), epithelial morphology and markers of regeneration, apoptosis, and cellular stress were assessed. The number of goblet cells in bronchial epithelium was much lower in mdx than in WT mice under all conditions. At 30 days, epithelial regeneration (PCNA positive cells) was higher in EX than SD animals in both groups; however, at 45 days, epithelial regeneration decreased in mdx mice irrespective of training, and the percentage of apoptotic (TUNEL positive) cells was higher in mdx-EX than in WT-EX mice. Epithelial expression of HSP60 (marker of stress) progressively decreased, and inversely correlated with epithelial apoptosis (r = -0.66, P = 0.01) only in mdx mice. Lack of dystrophin in mdx mice appears associated with defective epithelial differentiation, and transient epithelial regeneration during mild exercise training. Hence, lack of dystrophin might impair repair in bronchial epithelium, with potential clinical consequences in DMD patients. J. Cell. Physiol. 231: 2218-2223, 2016. © 2016 Wiley Periodicals, Inc.

  2. Response of macaque bronchiolar epithelium to ambient concentrations of ozone

    SciTech Connect

    Harkema, J.R.; Plopper, C.G.; Hyde, D.M.; St. George, J.A.; Wilson, D.W.; Dungworth, D.L. )

    1993-09-01

    Recently, we reported that exposure to ambient concentrations of ozone, near the U.S. National Ambient Air Quality Standard (0.12 ppm), induced significant nasal epithelial lesions in a non-human primate, the bonnet monkey. The present study defines the effects of ambient concentrations of ozone on the surface epithelium lining respiratory bronchioles and on the underlying bronchiolar interstitium in these same monkeys. Bonnet monkeys were exposed to filtered air or to 0.15 or 0.30 ppm ozone 8 hours/day for 6 or 90 days. At the end of exposures, monkeys were anesthetized and killed by exsanguination. Microdissected bronchiolar airways of infusion-fixed lungs were evaluated morphometrically by light microscopy and quantitatively by scanning and transmission electron microscopy for ozone-induced epithelial changes. Hyperplasia of nonciliated, cuboidal epithelial cells and intraluminal accumulation of macrophages characterized ozone-induced lesions in respiratory bronchioles. There were no significant differences in epithelial thickness or cell numbers among ozone-exposed groups. Ozone-exposed epithelium was composed of 80% cuboidal and 20% squamous cells compared with 40% cuboidal and 60% squamous cells in filtered air controls. In addition, the arithmetic mean thickness of the surface epithelium, a measure of tissue mass per unit area of basal lamina, was significantly increased in all of the ozone-exposed groups. The number of cuboidal epithelial cells per surface area of basal lamina was increased above control values by 780% after 6 days exposure to 0.15 ppm, 777% after 90 days to 0.15 ppm, and 996% after 90 days exposure to 0.30 ppm. There was also a significant ozone-induced increase in the thickness of the bronchiolar interstitium that was due to an increase in both cellular and acellular components.

  3. Morphologic changes in basal cells during repair of tracheal epithelium.

    PubMed Central

    Wang, C. Z.; Evans, M. J.; Cox, R. A.; Burke, A. S.; Zhu, Q.; Herndon, D. N.; Barrow, R. E.

    1992-01-01

    Basal cells are differentiated with respect to junctional adhesion mechanisms and play a role in attachment of columnar epithelium to the basal lamina. Although much is known about nonciliated and ciliated cell differentiation during the repair process after injury, little is known about the basal cell. We studied the morphology of basal cells and quantitated junctional adhesion structures during repair of tracheal epithelium exposed to toxic cotton smoke. Ten adult ewes were given a smoke injury to a portion of the upper cervical trachea and were killed at 4, 6, 8, 10, and 18 days after injury for morphometric studies. At 4 days, there was a stratified reparative epithelium over the basal lamina, which was two to four cells in depth. The basal cells were identified by their hemidesmosome (HD) attachment to the basal lamina. Basal cells were about 69% larger than controls and flattened rather than columnar. The amount of HD attachment was 192% greater than controls. In contrast, volume density of cytokeratin filaments had decreased about 47%. Basal cells had returned to normal numbers and size and a columnar shape by day 18. The amount of desmosome (D) and HD attachment and volume density of cytokeratins had also reached control levels by day 18. These data indicate that morphology of basal cells changes during the initial stages of reparative regeneration but returns to normal by 18 days. Morphologic changes appear to reflect changes in size of the cell associated with cell division rather than differentiation of recently divided basal cells. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:1381564

  4. In vitro reconstruction of human junctional and sulcular epithelium

    PubMed Central

    Dabija-Wolter, G; Bakken, V; Cimpan, M R; Johannessen, A C; Costea, D E

    2013-01-01

    BACKGROUND The aim of this study was to develop and characterize standardized in vitro three-dimensional organotypic models of human junctional epithelium (JE) and sulcular epithelium (SE). METHODS Organotypic models were constructed by growing human normal gingival keratinocytes on top of collagen matrices populated with gingival fibroblasts (GF) or periodontal ligament fibroblasts (PLF). Tissues obtained were harvested at different time points and assessed for epithelial morphology, proliferation (Ki67), expression of JE-specific markers (ODAM and FDC-SP), cytokeratins (CK), transglutaminase, filaggrin, and basement membrane proteins (collagen IV and laminin1). RESULTS The epithelial component in 3- and 5-day organotypics showed limited differentiation and expressed Ki-67, ODAM, FDC-SP, CK 8, 13, 16, 19, and transglutaminase in a similar fashion to control JE samples. PLF supported better than GF expression of CK19 and suprabasal proliferation, although statistically significant only at day 5. Basement membrane proteins started to be deposited only from day 5. The rate of proliferating cells as well as the percentage of CK19-expressing cells decreased significantly in 7- and 9-day cultures. Day 7 organotypics presented higher number of epithelial cell layers, proliferating cells in suprabasal layers, and CK expression pattern similar to SE. CONCLUSION Both time in culture and fibroblast type had impact on epithelial phenotype. Five-day cultures with PLF are suggested as JE models, 7-day cultures with PLF or GF as SE models, while 9-day cultures with GF as gingival epithelium (GE) models. Such standard, reproducible models represent useful tools to study periodontal bacteria–host interactions in vitro. PMID:22947066

  5. Connexins form functional hemichannels in porcine ciliary epithelium

    PubMed Central

    Shahidullah, Mohammad; Delamere, Nicholas A

    2014-01-01

    The expression of connexins in the ciliary epithelium is consistent with gap junctions between the pigmented (PE) and nonpigmented ciliary epithelium (NPE) that form when connexon hemichannels from adjacent cells pair to form a channel. Here we present evidence that suggests undocked connexons may form functional hemichannels that permit exchange of substances between NPE and the aqueous humor. Intact porcine eyes were perfused via the ciliary artery and propidium iodide (PI) (MW 668) was added to the aqueous humor compartment as a tracer. After calcium-free solution containing PI was introduced into the aqueous humor compartment for 30 min, fluorescence microscopy revealed PI in the NPE cell layer. PI entry into the NPE was inhibited by calcium and by the connexin antagonist 18α-glycyrrhetinic acid (18-AGA). Studies also were carried out with cultured porcine NPE. Under normal conditions, little PI entered the cultured cells but calcium-free medium stimulated PI accumulation and the entry was inhibited by 18-AGA. In cells loaded with calcein (MW 622), calcium-free solution stimulated calcein exit. 18-AGA partially suppressed calcein exit in calcium-free medium. Connexin 43 and connexin 50 proteins were detected by western blot analysis in both native and cultured NPE. In the intact eye, immunolocalization studies revealed connexin 50 at the basolateral, aqueous humor-facing, margin of the NPE. In contrast, connexin 43 was observed at the junction of the PE and NPE layer and on the basolateral membrane of PE. The results point to functional hemichannels at the NPE basolateral surface. It is feasible that hemichannels might contribute to the transfer of substances between the ciliary epithelium cytoplasm and aqueous humor. PMID:24262135

  6. Connexins form functional hemichannels in porcine ciliary epithelium.

    PubMed

    Shahidullah, Mohammad; Delamere, Nicholas A

    2014-01-01

    The expression of connexins in the ciliary epithelium is consistent with gap junctions between the pigmented (PE) and nonpigmented ciliary epithelium (NPE) that form when connexon hemichannels from adjacent cells pair to form a channel. Here we present evidence that suggests undocked connexons may form functional hemichannels that permit exchange of substances between NPE and the aqueous humor. Intact porcine eyes were perfused via the ciliary artery and propidium iodide (PI) (MW 668) was added to the aqueous humor compartment as a tracer. After calcium-free solution containing PI was introduced into the aqueous humor compartment for 30 min, fluorescence microscopy revealed PI in the NPE cell layer. PI entry into the NPE was inhibited by calcium and by the connexin antagonist 18α-glycyrrhetinic acid (18-AGA). Studies also were carried out with cultured porcine NPE. Under normal conditions, little PI entered the cultured cells but calcium-free medium stimulated PI accumulation and the entry was inhibited by 18-AGA. In cells loaded with calcein (MW 622), calcium-free solution stimulated calcein exit. 18-AGA partially suppressed calcein exit in calcium-free medium. Connexin 43 and connexin 50 proteins were detected by western blot analysis in both native and cultured NPE. In the intact eye, immunolocalization studies revealed connexin 50 at the basolateral, aqueous humor-facing, margin of the NPE. In contrast, connexin 43 was observed at the junction of the PE and NPE layer and on the basolateral membrane of PE. The results point to functional hemichannels at the NPE basolateral surface. It is feasible that hemichannels might contribute to the transfer of substances between the ciliary epithelium cytoplasm and aqueous humor.

  7. Expression of signaling components in embryonic eyelid epithelium.

    PubMed

    Meng, Qinghang; Jin, Chang; Chen, Yinglei; Chen, Jing; Medvedovic, Mario; Xia, Ying

    2014-01-01

    Closure of an epithelium opening is a critical morphogenetic event for development. An excellent example for this process is the transient closure of embryonic eyelid. Eyelid closure requires shape change and migration of epithelial cells at the tip of the developing eyelids, and is dictated by numerous signaling pathways. Here we evaluated gene expression in epithelial cells isolated from the tip (leading edge, LE) and inner surface epithelium (IE) of the eyelid from E15.5 mouse fetuses by laser capture microdissection (LCM). We showed that the LE and IE cells are different at E15.5, such that IE had higher expression of muscle specific genes, while LE acquired epithelium identities. Despite their distinct destinies, these cells were overall similar in expression of signaling components for the "eyelid closure pathways". However, while the LE cells had more abundant expression of Fgfr2, Erbb2, Shh, Ptch1 and 2, Smo and Gli2, and Jag1 and Notch1, the IE cells had more abundant expression of Bmp5 and Bmpr1a. In addition, the LE cells had more abundant expression of adenomatosis polyposis coli down-regulated 1 (Apcdd1), but the IE cells had high expression of Dkk2. Our results suggest that the functionally distinct LE and IE cells have also differential expression of signaling molecules that may contribute to the cell-specific responses to morphogenetic signals. The expression pattern suggests that the EGF, Shh and NOTCH pathways are preferentially active in LE cells, the BMP pathways are effective in IE cells, and the Wnt pathway may be repressed in LE and IE cells via different mechanisms.

  8. Nonequilibrium thermodynamic model of the rat proximal tubule epithelium.

    PubMed

    Weinstein, A M

    1983-11-01

    The rat proximal tubule epithelium is represented as well-stirred, compliant cellular and paracellular compartments bounded by mucosal and serosal bathing solutions. With a uniform pCO2 throughout the epithelium, the model variables include the concentrations of Na, K, Cl, HCO3, H2PO4, HPO4, and H, as well as hydrostatic pressure and electrical potential. Except for a metabolically driven Na-K exchanger at the basolateral cell membrane, all membrane transport within the epithelium is passive and is represented by the linear equations of nonequilibrium thermodynamics. In particular, this includes the cotransport of Na-Cl and Na-H2PO4 and countertransport of Na-H at the apical cell membrane. Experimental constraints on the choice of ionic conductivities are satisfied by allowing K-Cl cotransport at the basolateral membrane. The model equations include those for mass balance of the nonreacting species, as well as chemical equilibrium for the acidification reactions. Time-dependent terms are retained to permit the study of transient phenomena. In the steady state the energy dissipation is computed and verified equal to the sum of input from the Na-K exchanger plus the Gibbs free energy of mass addition to the system. The parameter dependence of coupled water transport is studied and shown to be consistent with the predictions of previous analytical models of the lateral intercellular space. Water transport in the presence of an end-proximal (HCO3-depleted) luminal solution is investigated. Here the lower permeability and higher reflection coefficient of HCO3 enhance net sodium and water transport. Due to enhanced flux across the tight junction, this process may permit proximal tubule Na transport to proceed with diminished energy dissipation.

  9. Expression of Signaling Components in Embryonic Eyelid Epithelium

    PubMed Central

    Meng, Qinghang; Jin, Chang; Chen, Yinglei; Chen, Jing; Medvedovic, Mario; Xia, Ying

    2014-01-01

    Closure of an epithelium opening is a critical morphogenetic event for development. An excellent example for this process is the transient closure of embryonic eyelid. Eyelid closure requires shape change and migration of epithelial cells at the tip of the developing eyelids, and is dictated by numerous signaling pathways. Here we evaluated gene expression in epithelial cells isolated from the tip (leading edge, LE) and inner surface epithelium (IE) of the eyelid from E15.5 mouse fetuses by laser capture microdissection (LCM). We showed that the LE and IE cells are different at E15.5, such that IE had higher expression of muscle specific genes, while LE acquired epithelium identities. Despite their distinct destinies, these cells were overall similar in expression of signaling components for the “eyelid closure pathways”. However, while the LE cells had more abundant expression of Fgfr2, Erbb2, Shh, Ptch1 and 2, Smo and Gli2, and Jag1 and Notch1, the IE cells had more abundant expression of Bmp5 and Bmpr1a. In addition, the LE cells had more abundant expression of adenomatosis polyposis coli down-regulated 1 (Apcdd1), but the IE cells had high expression of Dkk2. Our results suggest that the functionally distinct LE and IE cells have also differential expression of signaling molecules that may contribute to the cell-specific responses to morphogenetic signals. The expression pattern suggests that the EGF, Shh and NOTCH pathways are preferentially active in LE cells, the BMP pathways are effective in IE cells, and the Wnt pathway may be repressed in LE and IE cells via different mechanisms. PMID:24498290

  10. Stomatin immunoreactivity in ciliated cells of the human airway epithelium.

    PubMed

    Fricke, Britta; Stewart, Gordon W; Treharne, Kathryn J; Mehta, Anil; Knöpfle, Gisela; Friedrichs, Nicolaus; Müller, Klaus-Michael; von Düring, Monika

    2003-07-01

    Stomatin is a widely distributed 32kD membrane protein of unknown function. In biochemical studies it is associated with cholesterol+sphingomyelin-rich 'rafts' in the cytomembrane. Genetic studies in C. elegans, supported by microscopic studies in mammalian tissue and co-expression studies in oocytes, suggest a functional link with the DEG/ENaC (degenerin/epithelial Na+ channel) superfamily of monovalent ion channels. Since ENaC channels play a prominent role in the physiology of the respiratory epithelium, we have studied the immunolocalization of stomatin in mature and developing human airway epithelium by means of Western blot analysis, immunocytochemistry, and immunoelectron microscopy. Stomatin immunoreactivity (stomatin-IR) was found in the ciliated cells of the conductive airway epithelium in a distinct distribution pattern with the strongest signal along the cilia. Immunogold labelling revealed immunogold particles at the basal bodies, along the cilia, and at the membrane of the microvilli. The presence of stomatin-IR paralleled the stages of ciliogenesis in airway development, and its appearance preceded the elongation of the axoneme and the cilial outgrowth. Due to its presence in the different cellular locations in the ciliated cell, we suggest that stomatin is involved in various cellular functions. From its ultrastructural position, stomatin could be a candidate for a membrane-associated mechanotransducer with a role in the control of ciliary motility. Stomatin as a raft protein might be a microtubule associated protein moving along the outer surface of the microtubules to its terminal site of action in the cilia. Stomatin-IR in microvilli supports the hypothesis of a co-localization with beta- and gamma- ENaC and, in conclusion, their potential functional interaction to control the composition of periciliary mucus electrolytes. PMID:12759749

  11. Diet, Microbiome, and the Intestinal Epithelium: An Essential Triumvirate?

    PubMed Central

    Guzman, Javier Rivera; Conlin, Victoria Susan; Jobin, Christian

    2013-01-01

    The intestinal epithelium represents a critical barrier protecting the host against diverse luminal noxious agents, as well as preventing the uncontrolled uptake of bacteria that could activate an immune response in a susceptible host. The epithelial monolayer that constitutes this barrier is regulated by a meshwork of proteins that orchestrate complex biological function such as permeability, transepithelial electrical resistance, and movement of various macromolecules. Because of its key role in maintaining host homeostasis, factors regulating barrier function have attracted sustained attention from the research community. This paper will address the role of bacteria, bacterial-derived metabolism, and the interplay of dietary factors in controlling intestinal barrier function. PMID:23586037

  12. Expression of stanniocalcin in the epithelium of human choroid plexus.

    PubMed

    Franzén, A M; Zhang, K Z; Westberg, J A; Zhang, W M; Arola, J; Olsen, H S; Andersson, L C

    2000-12-29

    Stanniocalcin (STC) is a 28 kD glycoprotein hormone originally found in bony fish in which it regulates calcium/phosphate homeostasis and protects against hypercalcemia. The recently characterized mammalian STC shows about 70% homology with fish STC. The epithelial cells of proximal tubuli in human and rat kidney and brain neurons have been found to express STC. Here we show that the epithelium of the choroid plexus, already at 16 weeks of fetal age, and of plexus papillomas, synthesize and express STC. Our findings suggest that STC may be of importance for the distribution of calcium and phosphate between the cerebrospinal fluid and blood. PMID:11134638

  13. Combined hamartoma of the retina and retinal pigment epithelium

    PubMed Central

    Xue, Kanmin; Mellington, Faye; Gout, Irina; Rokerya, Sofia; Olurin, Oyinkan Ibironke; El-Amir, Ahmed

    2012-01-01

    We report two cases of combined hamatoma of the retina and retinal pigment epithelium (CHR-RPE), illustrated with ultrasonography, optical coherence tomography, fundus fluorescein angiography and indocyanine green angiography images. CHR-RPE could clinically mimic several other retinal conditions. Failure to distinguish it from serious malignancies such as choroidal melanoma or retinoblastoma has led to unnecessary enucleation in the past. Through these case reports and a review of literature, we show the diagnostic features of CHR-RPE, its key differential diagnoses and the management options. PMID:23162024

  14. Role of pigment epithelium-derived factor in the reproductive system.

    PubMed

    Chuderland, Dana; Ben-Ami, Ido; Bar-Joseph, Hadas; Shalgi, Ruth

    2014-10-01

    The physiological function of the female reproductive organs is hormonally controlled. In each cycle, the reproductive organs undergo tissue modifications that are accompanied by formation and destruction of blood vessels. Proper angiogenesis requires an accurate balance between stimulatory and inhibitory signals, provided by pro- and anti-angiogenic factors. As with many other tissues, vascular endothelial growth factor (VEGF) appears to be one of the major pro-angiogenic factors in the female reproductive organs. Pigment epithelium-derived factor (PEDF) is a non-inhibitory member of the serine protease inhibitors (serpin) superfamily, possessing potent physiologic anti-angiogenic activity that negates VEGF activity. The role of PEDF in decreasing abnormal neovascularization by exerting its anti-angiogenic effect that inhibits pro-angiogenic factors, including VEGF, has been investigated mainly in the eye and in cancer. This review summarizes the function of PEDF in the reproductive system, showing its hormonal regulation and its anti-angiogenic activity. Furthermore, some pathologies of the female reproductive organs, including endometriosis, ovarian hyperstimulation syndrome, polycystic ovary syndrome, and others, are associated with a faulty angiogenic process. This review illuminates the role of PEDF in their pathogenesis and treatment. Collectively, we can conclude that although PEDF seems to play an essential role in the physiology and pathophysiology of the reproductive system, its full role and mechanism of action still need to be elucidated.

  15. Histone deacetylase 1 and 2 regulate Wnt and p53 pathways in the ureteric bud epithelium

    PubMed Central

    Chen, Shaowei; Yao, Xiao; Li, Yuwen; Saifudeen, Zubaida; Bachvarov, Dimcho; El-Dahr, Samir S.

    2015-01-01

    Histone deacetylases (HDACs) regulate a broad range of biological processes through removal of acetyl groups from histones as well as non-histone proteins. Our previous studies showed that Hdac1 and Hdac2 are bound to promoters of key renal developmental regulators and that HDAC activity is required for embryonic kidney gene expression. However, the existence of many HDAC isoforms in embryonic kidneys raises questions concerning the possible specificity or redundancy of their functions. We report here that targeted deletion of both the Hdac1 and Hdac2 genes from the ureteric bud (UB) cell lineage of mice causes bilateral renal hypodysplasia. One copy of either Hdac1 or Hdac2 is sufficient to sustain normal renal development. In addition to defective cell proliferation and survival, genome-wide transcriptional profiling revealed that the canonical Wnt signaling pathway is specifically impaired in UBHdac1,2−/− kidneys. Our results also demonstrate that loss of Hdac1 and Hdac2 in the UB epithelium leads to marked hyperacetylation of the tumor suppressor protein p53 on lysine 370, 379 and 383; these post-translational modifications are known to boost p53 stability and transcriptional activity. Genetic deletion of p53 partially rescues the development of UBHdac1,2−/− kidneys. Together, these data indicate that Hdac1 and Hdac2 are crucial for kidney development. They perform redundant, yet essential, cell lineage-autonomous functions via p53-dependent and -independent pathways. PMID:25758227

  16. Bacterial cellulose as a support for the growth of retinal pigment epithelium.

    PubMed

    Gonçalves, Sara; Padrão, Jorge; Rodrigues, Inês Patrício; Silva, João Pedro; Sencadas, Vítor; Lanceros-Mendez, Senentxu; Girão, Henrique; Dourado, Fernando; Rodrigues, Lígia R

    2015-04-13

    The feasibility of bacterial cellulose (BC) as a novel substrate for retinal pigment epithelium (RPE) culture was evaluated. Thin (41.6 ± 2.2 μm of average thickness) and heat-dried BC substrates were surface-modified via acetylation and polysaccharide adsorption, using chitosan and carboxymethyl cellulose. All substrates were characterized according to their surface chemistry, wettability, energy, topography, and also regarding their permeability, dimensional stability, mechanical properties, and endotoxin content. Then, their ability to promote RPE cell adhesion and proliferation in vitro was assessed. All surface-modified BC substrates presented similar permeation coefficients with solutes of up to 300 kDa. Acetylation of BC decreased it's swelling and the amount of endotoxins. Surface modification of BC greatly enhanced the adhesion and proliferation of RPE cells. All samples showed similar stress-strain behavior; BC and acetylated BC showed the highest elastic modulus, but the latter exhibited a slightly smaller tensile strength and elongation at break as compared to pristine BC. Although similar proliferation rates were observed among the modified substrates, the acetylated ones showed higher initial cell adhesion. This difference may be mainly due to the moderately hydrophilic surface obtained after acetylation. PMID:25748276

  17. Bacterial cellulose as a support for the growth of retinal pigment epithelium.

    PubMed

    Gonçalves, Sara; Padrão, Jorge; Rodrigues, Inês Patrício; Silva, João Pedro; Sencadas, Vítor; Lanceros-Mendez, Senentxu; Girão, Henrique; Dourado, Fernando; Rodrigues, Lígia R

    2015-04-13

    The feasibility of bacterial cellulose (BC) as a novel substrate for retinal pigment epithelium (RPE) culture was evaluated. Thin (41.6 ± 2.2 μm of average thickness) and heat-dried BC substrates were surface-modified via acetylation and polysaccharide adsorption, using chitosan and carboxymethyl cellulose. All substrates were characterized according to their surface chemistry, wettability, energy, topography, and also regarding their permeability, dimensional stability, mechanical properties, and endotoxin content. Then, their ability to promote RPE cell adhesion and proliferation in vitro was assessed. All surface-modified BC substrates presented similar permeation coefficients with solutes of up to 300 kDa. Acetylation of BC decreased it's swelling and the amount of endotoxins. Surface modification of BC greatly enhanced the adhesion and proliferation of RPE cells. All samples showed similar stress-strain behavior; BC and acetylated BC showed the highest elastic modulus, but the latter exhibited a slightly smaller tensile strength and elongation at break as compared to pristine BC. Although similar proliferation rates were observed among the modified substrates, the acetylated ones showed higher initial cell adhesion. This difference may be mainly due to the moderately hydrophilic surface obtained after acetylation.

  18. The effects of lithogenic bile on gallbladder epithelium.

    PubMed Central

    Moody, F G; Haley-Russell, D; Li, Y F; Husband, K J; Weisbrodt, N W; Dewey, R B

    1989-01-01

    Prairie dogs were fed a 1.2% cholesterol diet for up to 24 weeks to evaluate the effects of lithogenic bile on the mucosa of the gallbladder. There was a progressive increase in the lithogenic index of the gallbladder bile (1.44 +/- 0.15 at 4 weeks, p less than 0.05). Fifty-five of 70 animals developed gallstones between the second and fourth week. Increasing stone burden was associated with a 27% (p less than 0.05) decrease in the electrical resistance of the epithelium and a 60% (p less than 0.05) decrease in net sodium transport when measured isotopically in an Ussing chamber (3 weeks). After 4 months, seven of ten animals developed inflammatory mucosal polyps characterized by a heavy infiltration of plasma cells into an expanded matrix. Cellular infiltration began as early as 2 weeks. These changes occurred without alterations in the ultrastructural appearance of the epithelium. Images Figs. 3A and B. Figs. 4A and B. Figs. 4A and B. Figs. 5A and B. PMID:2774711

  19. The growth and differentiation of transitional epithelium in vitro

    PubMed Central

    1979-01-01

    The development of rat transitional epithelial cells grown on conventional non-permeable surfaces was compared with development on permeable collagen supports. On glass or plastic surfaces, cells grew as expanding nomolayer sheets. Once confluent, growth continued with a bilayer being formed in most areas and apical cells being continuously sloughed off. Although most cells were interconnected by desmosomes, and junctional complexes were formed, no other indications of differentiation were observed. After 2-3 wk of growth, division stopped and cel death ensued. In contrast, single-cell suspensions plated on collagen-coated nylon disks reassociated into multicellular islands and commenced growth. Mitoses were confined to the basal cells in contact with the permeable substrate. The islands developed into epithelial trilayers, tapering to monolayers along spreading edges. Once the islands were confluent, stratification was completed and appeared similar to that observed in vivo. Germinal cells formed a basal lamina, and the upper layer was composed of large, flattened cells with an unusually thick asymmetrical plasma membrane on the apical surface. Electron microscopic and radioactive tracers demonstrated "leaky" zonulae occludentes with a restricted permeability to small molecules. The movement of urea was retarded in comparison to water. Unlike the slow turnover of adult epithelium in vivo, maturation and sloughing of apical cells were measurable. Transfer of cells could be effected and growth maintained for up to 4 mo. These results may indicate the necessity of a nutrient-permeable growth surface for the polarized differentiation of adult transitional epithelium. PMID:574872

  20. Coordination of Cellular Dynamics Contributes to Tooth Epithelium Deformations

    PubMed Central

    Morita, Ritsuko; Kihira, Miho; Nakatsu, Yousuke; Nomoto, Yohei; Ogawa, Miho; Ohashi, Kazumasa; Mizuno, Kensaku; Tachikawa, Tetsuhiko; Ishimoto, Yukitaka; Morishita, Yoshihiro; Tsuji, Takashi

    2016-01-01

    The morphologies of ectodermal organs are shaped by appropriate combinations of several deformation modes, such as invagination and anisotropic tissue elongation. However, how multicellular dynamics are coordinated during deformation processes remains to be elucidated. Here, we developed a four-dimensional (4D) analysis system for tracking cell movement and division at a single-cell resolution in developing tooth epithelium. The expression patterns of a Fucci probe clarified the region- and stage-specific cell cycle patterns within the tooth germ, which were in good agreement with the pattern of the volume growth rate estimated from tissue-level deformation analysis. Cellular motility was higher in the regions with higher growth rates, while the mitotic orientation was significantly biased along the direction of tissue elongation in the epithelium. Further, these spatio-temporal patterns of cellular dynamics and tissue-level deformation were highly correlated with that of the activity of cofilin, which is an actin depolymerization factor, suggesting that the coordination of cellular dynamics via actin remodeling plays an important role in tooth epithelial morphogenesis. Our system enhances the understanding of how cellular behaviors are coordinated during ectodermal organogenesis, which cannot be observed from histological analyses. PMID:27588418

  1. Regulation of gene expression in the intestinal epithelium.

    PubMed

    Richmond, Camilla A; Breault, David T

    2010-01-01

    Regulation of gene expression within the intestinal epithelium is complex and controlled by various signaling pathways that regulate the balance between proliferation and differentiation. Proliferation is required both to grow and to replace cells lost through apoptosis and attrition, yet in all but a few cells, differentiation must take place to prevent uncontrolled growth (cancer) and to provide essential functions. In this chapter, we review the major signaling pathways underlying regulation of gene expression within the intestinal epithelium, based primarily on data from mouse models, as well as specific morphogens and transcription factor families that have a major role in regulating intestinal gene expression, including the Hedgehog family, Forkhead Box (FOX) factors, Homeobox (HOX) genes, ParaHox genes, GATA transcription factors, canonical Wnt/β-catenin signaling, EPH/Ephrins, Sox9, BMP signaling, PTEN/PI3K, LKB1, K-RAS, Notch pathway, HNF, and MATH1. We also briefly highlight important emerging areas of gene regulation, including microRNA (miRNA) and epigenetic regulation. PMID:21075346

  2. Aldehyde dehydrogenase induction in arsenic-exposed rat bladder epithelium.

    PubMed

    Huang, Ya-Chun; Yu, Hsin-Su; Chai, Chee-Yin

    2016-01-01

    Arsenic is widely distributed in the environment. Many human cancers, including urothelial carcinoma (UC), show a dose-dependent relationship with arsenic exposure in the south-west coast of Taiwan (also known as the blackfoot disease (BFD) areas). However, the molecular mechanisms of arsenic-mediated UC carcinogenesis has not yet been defined. In vivo study, the rat bladder epithelium were exposed with arsenic for 48 h. The proteins were extracted from untreated and arsenic-treated rat bladder cells and utilized two-dimensional gel electrophoresis and mass spectrometry. Selected peptides were extracted from the gel and identified by quadrupole-time of flight (Q-TOF) Ultima-Micromass spectra. The significantly difference expression of proteins in arsenic-treated groups as compared with untreated groups was confirmed by immunohistochemistry (IHC) and western blotting. We found that thirteen proteins were down-regulated and nine proteins were up-regulated in arsenic-treated rat bladder cells when compared with untreated groups. The IHC and western blotting results confirmed that aldehyde dehydrogenase (ALDH) protein was up-regulated in arsenic-treated rat bladder epithelium. Expression of ALDH protein was significantly higher in UC patients from BFD areas than those from non-BFD areas using IHC (p=0.018). In conclusion, the ALDH protein expression could be used as molecular markers for arsenic-induced transformation.

  3. REGULATION OF GENE EXPRESSION IN THE INTESTINAL EPITHELIUM

    PubMed Central

    Richmond, Camilla A.; Breault, David T.

    2013-01-01

    Regulation of gene expression within the intestinal epithelium is complex and controlled by various signaling pathways that regulate the balance between proliferation and differentiation. Proliferation is required both to grow and to replace cells lost through apoptosis and attrition, yet in all but a few cells, differentiation must take place to prevent uncontrolled growth (cancer) and to provide essential functions. In this chapter, we will review the major signaling pathways underlying regulation of gene expression within the intestinal epithelium, based primarily on data from mouse models, as well as specific morphogens and transcription factor families that have a major role in regulating intestinal gene expression, including: the Hedgehog family, Forkhead Box (FOX) factors, Homeobox (HOX) genes, ParaHox genes, GATA transcription factors, canonical Wnt/β-catenin signaling, EPH/Ephrins, Sox9, BMP signaling, PTEN/PI3K, LKB1, K-RAS, Notch pathway, HNF and MATH1. We will also briefly highlight important emerging areas of gene regulation including microRNA and epigenetic regulation. PMID:21075346

  4. Selective gene expression by rat gastric corpus epithelium

    PubMed Central

    Goebel, M.; Stengel, A.; Sachs, G.

    2011-01-01

    The gastrointestinal (GI) tract is divided into several segments that have distinct functional properties, largely absorptive. The gastric corpus is the only segment thought of as largely secretory. Microarray hybridization of the gastric corpus mucosal epithelial cells was used to compare gene expression with other segments of the columnar GI tract followed by statistical data subtraction to identify genes selectively expressed by the rat gastric corpus mucosa. This provides a means of identifying less obvious specific functions of the corpus in addition to its secretion-related genes. For example, important properties found by this GI tract comparative transcriptome reflect the energy demand of acid secretion, a role in lipid metabolism, the large variety of resident neuroendocrine cells, responses to damaging agents and transcription factors defining differentiation of its epithelium. In terms of overlap of gastric corpus genes with the rest of the GI tract, the distal small bowel appears to express many of the gastric corpus genes in contrast to proximal small and large bowel. This differential map of gene expression by the gastric corpus epithelium will allow a more detailed description of major properties of the gastric corpus and may lead to the discovery of gastric corpus cell differentiation genes and those mis-regulated in gastric carcinomas. PMID:21177383

  5. Nanotopography follows force in TGF-β1 stimulated epithelium

    NASA Astrophysics Data System (ADS)

    Thoelking, Gerold; Reiss, Bjoern; Wegener, Joachim; Oberleithner, Hans; Pavenstaedt, Hermann; Riethmuller, Christoph

    2010-07-01

    Inflammation and cellular fibrosis often imply an involvement of the cytokine TGF-β1. TGF-β1 induces epithelial-to-mesenchymal transdifferentiation (EMT), a term describing the loss of epithelium-specific function. Indicative for this process are an elongated cell shape parallel to stress fibre formation. Many signalling pathways of TGF-β1 have been discovered, but mechanical aspects have not yet been investigated. In this study, atomic force microscopy (AFM) was used to analyse surface topography and mechanical properties of EMT in proximal kidney tubule epithelium (NRK52E). Elongated cells, an increase of stress fibre formation and a loss of microvillus compatible structures were observed as characteristic signs of EMT. Furthermore, AFM could identify an increase in stiffness by 71% after six days of stimulation with TGF-β1. As a novel topographical phenomenon, nodular protrusions emerged at the cell-cell junctions. They occurred preferentially at sites where stress fibres cross the border. Since these nodular protrusions were sensitive to inhibitors of force generation, they can indicate intracellular tension. The results demonstrate a manifest impact of elevated tension on the cellular topography.

  6. Mechanisms of Acid and Base Secretion by the Airway Epithelium

    PubMed Central

    Fischer, Horst; Widdicombe, Jonathan H.

    2010-01-01

    SUMMARY One of the main functions of the airway epithelium is to inactivate and remove infectious particles from inhaled air and thereby prevent infection of the distal lung. This function is achieved by mucociliary and cough clearance and by antimicrobial factors present in the airway surface liquid (ASL). There are indications that airway defenses are affected by the pH of the ASL and historically, acidification of the airway surfaces has been suggested as a measure of airway disease. However, even in health, the ASL is slightly acidic, and this acidity might be part of normal airway defense. Only recently research has focused on the mechanisms responsible for acid and base secretion into the ASL. Advances resulted from research into the airway disease associated with cystic fibrosis (CF) after it was found that the CFTR C1- channel conducts HCO3- and, therefore, may contribute to ASL pH. However, the acidity of the ASL indicated parallel mechanisms for H+ secretion. Recent investigations identified several H+ transporters in the apical membrane of the airway epithelium. These include H+ channels and ATP-driven H+ pumps, including a non-gastric isoform of the H+-K+ ATPase and a vacuolar-type H+ ATPase. Current knowledge of acid and base transporters and their potential roles in airway mucosal pH regulation is reviewed here. PMID:17091214

  7. An Apical-Membrane Chloride Channel in Human Tracheal Epithelium

    NASA Astrophysics Data System (ADS)

    Welsh, Michael J.

    1986-06-01

    The mechanism of chloride transport by airway epithelia has been of substantial interest because airway and sweat gland-duct epithelia are chloride-impermeable in cystic fibrosis. The decreased chloride permeability prevents normal secretion by the airway epithelium, thereby interfering with mucociliary clearance and contributing to the morbidity and mortality of the disease. Because chloride secretion depends on and is regulated by chloride conductance in the apical cell membrane, the patch-clamp technique was used to directly examine single-channel currents in primary cultures of human tracheal epithelium. The cells contained an anion-selective channel that was not strongly voltage-gated or regulated by calcium in cell-free patches. The channel was also blocked by analogs of carboxylic acid that decrease apical chloride conductance in intact epithelia. When attached to the cell, the channel was activated by isoproterenol, although the channel was also observed to open spontaneously. However, in some cases, the channel was only observed after the patch was excised from the cell. These results suggest that this channel is responsible for the apical chloride conductance in airway epithelia.

  8. New insights in wound response and repair of epithelium.

    PubMed

    Chi, Cheryl; Trinkaus-Randall, Vickery

    2013-05-01

    Epithelial wounds usually heal relatively quickly, but repair may be impaired by environmental stressors, such as hypoxic or diabetic states, rendering patients vulnerable to a number of corneal pathologies. Though this response appears simple, at first, years of research have uncovered the complicated biochemical pathways coordinating the wound healing response. Here, we investigate signaling cascades and individual proteins involved in the corneal epithelium's self-repair. We will explore how an epithelial cell migrates across the wound bed and attaches itself to its new post-injury surroundings, including its neighboring cells and the basement membrane, through focal adhesions and hemidesmosomes. We will also discuss how the cell coordinates this motion physiologically, through calcium signaling and protein phosphorylation, focusing on the communication through purinergic, glutamatergic, and growth factor receptors. Many of these aspects reflect and can be extended to similar epithelial surfaces, and can be used to facilitate wound healing in patients with various underlying pathologies. The collective library of laboratory and clinical research done around the world has demonstrated how important precise regulation of these processes is in order for the injured corneal epithelium to properly heal.

  9. Sessile alveolar macrophages communicate with alveolar epithelium to modulate immunity

    NASA Astrophysics Data System (ADS)

    Westphalen, Kristin; Gusarova, Galina A.; Islam, Mohammad N.; Subramanian, Manikandan; Cohen, Taylor S.; Prince, Alice S.; Bhattacharya, Jahar

    2014-02-01

    The tissue-resident macrophages of barrier organs constitute the first line of defence against pathogens at the systemic interface with the ambient environment. In the lung, resident alveolar macrophages (AMs) provide a sentinel function against inhaled pathogens. Bacterial constituents ligate Toll-like receptors (TLRs) on AMs, causing AMs to secrete proinflammatory cytokines that activate alveolar epithelial receptors, leading to recruitment of neutrophils that engulf pathogens. Because the AM-induced response could itself cause tissue injury, it is unclear how AMs modulate the response to prevent injury. Here, using real-time alveolar imaging in situ, we show that a subset of AMs attached to the alveolar wall form connexin 43 (Cx43)-containing gap junction channels with the epithelium. During lipopolysaccharide-induced inflammation, the AMs remained sessile and attached to the alveoli, and they established intercommunication through synchronized Ca2+ waves, using the epithelium as the conducting pathway. The intercommunication was immunosuppressive, involving Ca2+-dependent activation of Akt, because AM-specific knockout of Cx43 enhanced alveolar neutrophil recruitment and secretion of proinflammatory cytokines in the bronchoalveolar lavage. A picture emerges of a novel immunomodulatory process in which a subset of alveolus-attached AMs intercommunicates immunosuppressive signals to reduce endotoxin-induced lung inflammation.

  10. Esophageal epithelium of women with AIDS: thickness and local immunity.

    PubMed

    Rocha, Laura; Silva, Renata; Olegário, Janaínna; Corrêa, Rosana; Teixeira, Vicente; Cavellani, Camila

    2010-04-15

    The aim of this study was to evaluate the morphological characteristics of the esophageal epithelium (EE) and its local immunity. Esophageal fragments of autopsied women were collected from 1980 to 2008, and two groups were analyzed: with AIDS (n=17) and without AIDS (n=12). The measurement of the esophageal epithelium was carried out through the image analysis software ImageJ, and the immunostaining of Langerhans cells (LCs) was carried out using anti-S100 antibody. Women with AIDS, when compared with women without AIDS, had significantly thinner EE (220.6 versus 243.5 microm), a less number of LCs (6.2 versus 18.8 LCs/mm(2)), and a higher percentage of immature or morphologically altered LCs (66.6 versus 40.0%). The malnourished women, when compared with normonourished women, regardless of AIDS, had significantly thinner EE (227.1 versus 238.0 microm) and a less number of LCs (6.2 versus 12.5 LCs/mm(2)). The percentage of immature or morphologically altered LCs was the same in both groups. Additionally, the women with AIDS (7.0 versus 2.8%) and the malnourished women (5.8 versus 3.1%) presented a significantly higher percentage of fibrosis. We concluded that AIDS and malnutrition contribute to the decrease in esophagus local immunity and, therefore, to a possible increase in local opportunistic infections.

  11. Coordination of Cellular Dynamics Contributes to Tooth Epithelium Deformations.

    PubMed

    Morita, Ritsuko; Kihira, Miho; Nakatsu, Yousuke; Nomoto, Yohei; Ogawa, Miho; Ohashi, Kazumasa; Mizuno, Kensaku; Tachikawa, Tetsuhiko; Ishimoto, Yukitaka; Morishita, Yoshihiro; Tsuji, Takashi

    2016-01-01

    The morphologies of ectodermal organs are shaped by appropriate combinations of several deformation modes, such as invagination and anisotropic tissue elongation. However, how multicellular dynamics are coordinated during deformation processes remains to be elucidated. Here, we developed a four-dimensional (4D) analysis system for tracking cell movement and division at a single-cell resolution in developing tooth epithelium. The expression patterns of a Fucci probe clarified the region- and stage-specific cell cycle patterns within the tooth germ, which were in good agreement with the pattern of the volume growth rate estimated from tissue-level deformation analysis. Cellular motility was higher in the regions with higher growth rates, while the mitotic orientation was significantly biased along the direction of tissue elongation in the epithelium. Further, these spatio-temporal patterns of cellular dynamics and tissue-level deformation were highly correlated with that of the activity of cofilin, which is an actin depolymerization factor, suggesting that the coordination of cellular dynamics via actin remodeling plays an important role in tooth epithelial morphogenesis. Our system enhances the understanding of how cellular behaviors are coordinated during ectodermal organogenesis, which cannot be observed from histological analyses. PMID:27588418

  12. Aldehyde dehydrogenase induction in arsenic-exposed rat bladder epithelium.

    PubMed

    Huang, Ya-Chun; Yu, Hsin-Su; Chai, Chee-Yin

    2016-01-01

    Arsenic is widely distributed in the environment. Many human cancers, including urothelial carcinoma (UC), show a dose-dependent relationship with arsenic exposure in the south-west coast of Taiwan (also known as the blackfoot disease (BFD) areas). However, the molecular mechanisms of arsenic-mediated UC carcinogenesis has not yet been defined. In vivo study, the rat bladder epithelium were exposed with arsenic for 48 h. The proteins were extracted from untreated and arsenic-treated rat bladder cells and utilized two-dimensional gel electrophoresis and mass spectrometry. Selected peptides were extracted from the gel and identified by quadrupole-time of flight (Q-TOF) Ultima-Micromass spectra. The significantly difference expression of proteins in arsenic-treated groups as compared with untreated groups was confirmed by immunohistochemistry (IHC) and western blotting. We found that thirteen proteins were down-regulated and nine proteins were up-regulated in arsenic-treated rat bladder cells when compared with untreated groups. The IHC and western blotting results confirmed that aldehyde dehydrogenase (ALDH) protein was up-regulated in arsenic-treated rat bladder epithelium. Expression of ALDH protein was significantly higher in UC patients from BFD areas than those from non-BFD areas using IHC (p=0.018). In conclusion, the ALDH protein expression could be used as molecular markers for arsenic-induced transformation. PMID:26482281

  13. microRNA-dependent Temporal Gene Expression in the Ureteric Bud Epithelium during Mammalian Kidney Development

    PubMed Central

    Nagalakshmi, Vidya K.; Lindner, Volkhard; Wessels, Andy; Yu, Jing

    2014-01-01

    Background Our previous study on mouse mutants with the ureteric bud (UB) epithelium-specific Dicer deletion (Dicer UB mutants) demonstrated the significance of UB epithelium-derived miRNAs in UB development. Results Our whole-genome transcriptional profiling showed that the Dicer mutant UB epithelium abnormally retained transcriptional features of the early UB epithelium and failed to express many genes associated with collecting duct differentiation. Further, we identified a temporal expression pattern of early UB genes during UB epithelium development in which gene expression was detected at early developmental stages and became undetectable by E14.5. In contrast, expression of early UB genes persisted at later stages in the Dicer mutant UB epithelium and increased at early stages. Our bioinformatics analysis of the abnormally persistently expressed early genes in the Dicer mutant UB epithelium showed significant enrichment of the let-7 family miRNA targets. We further identified a temporal expression pattern of let-7 miRNAs in the UB epithelium that is anti-parallel to that of some early UB genes during kidney development. Conclusions We propose a model in which the let-7 family miRNAs silence the expression of a subset of early genes in the UB epithelium at later developmental stages in order to promote collecting duct differentiation. PMID:25369991

  14. Ultrastructural studies of the transitional zone in the nasopharyngeal epithelium, with special reference to the keratinizing process in the mouse.

    PubMed

    Nakano, T

    1986-01-01

    In the nasopharynx of the SMA mouse, the 'intermediate epithelium' occupies the transitional zone between the ciliated columnar and the stratified squamous epithelia. The intermediate epithelium showed gradations ranging from ciliated stratified low-columnar through stratified cuboidal to stratified squamous type. It is suggested that the intermediate epithelium shows the various stages of the epithelium transforming from the ciliated columnar to the stratified squamous epithelium, and that the basal cells of the ciliated columnar epithelium serve as the germinal layer for the transformation. The intermediate epithelium containing a few keratohyalin granules and many membrane-coating granules represented earlier stages of keratinization. The width of the microprojections in the stratified squamous epithelium was about doubled compared to that in the intermediate epithelium. It is suggested that the difference in width is caused by cell membrane distortion associated with keratinization and is regarded as an important marker of the start of keratinization.

  15. Response of macaque bronchiolar epithelium to ambient concentrations of ozone.

    PubMed Central

    Harkema, J. R.; Plopper, C. G.; Hyde, D. M.; St George, J. A.; Wilson, D. W.; Dungworth, D. L.

    1993-01-01

    Recently, we reported that exposure to ambient concentrations of ozone, near the U.S. National Ambient Air Quality Standard (0.12 ppm), induced significant nasal epithelial lesions in a non-human primate, the bonnet monkey. The present study defines the effects of ambient concentrations of ozone on the surface epithelium lining respiratory bronchioles and on the underlying bronchiolar interstitium in these same monkeys. Bonnet monkeys were exposed to filtered air or to 0.15 or 0.30 ppm ozone 8 hours/day for 6 or 90 days. At the end of exposures, monkeys were anesthetized and killed by exsanguination. Microdissected bronchiolar airways of infusion-fixed lungs were evaluated morphometrically by light microscopy and quantitatively by scanning and transmission electron microscopy for ozone-induced epithelial changes. Hyperplasia of nonciliated, cuboidal epithelial cells and intraluminal accumulation of macrophages characterized ozone-induced lesions in respiratory bronchioles. There were no significant differences in epithelial thickness or cell numbers among ozone-exposed groups. Ozone-exposed epithelium was composed of 80% cuboidal and 20% squamous cells compared with 40% cuboidal and 60% squamous cells in filtered air controls. In addition, the arithmetic mean thickness of the surface epithelium, a measure of tissue mass per unit area of basal lamina, was significantly increased in all of the ozone-exposed groups. The number of cuboidal epithelial cells per surface area of basal lamina was increased above control values by 780% after 6 days exposure to 0.15 ppm, 777% after 90 days to 0.15 ppm, and 996% after 90 days exposure to 0.30 ppm. There was also a significant ozone-induced increase in the thickness of the bronchiolar interstitium that was due to an increase in both cellular and acellular components. These results demonstrate that exposure to low ambient concentrations of ozone, near the current. National Ambient Air Quality Standard, induces pulmonary lesions

  16. Non-thermal electromagnetic radiation damage to lens epithelium.

    PubMed

    Bormusov, Elvira; P Andley, Usha; Sharon, Naomi; Schächter, Levi; Lahav, Assaf; Dovrat, Ahuva

    2008-05-21

    High frequency microwave electromagnetic radiation from mobile phones and other modern devices has the potential to damage eye tissues, but its effect on the lens epithelium is unknown at present. The objective of this study was to investigate the non-thermal effects of high frequency microwave electromagnetic radiation (1.1GHz, 2.22 mW) on the eye lens epithelium in situ. Bovine lenses were incubated in organ culture at 35°C for 10-15 days. A novel computer-controlled microwave source was used to investigate the effects of microwave radiation on the lenses. 58 lenses were used in this study. The lenses were divided into four groups: (1) Control lenses incubated in organ culture for 10 to15 days. (2) Electromagnetic radiation exposure group treated with 1.1 GHz, 2.22 mW microwave radiation for 90 cycles of 50 minutes irradiation followed by 10 minutes pause and cultured up to 10 days. (3) Electromagnetic radiation exposure group treated as group 2 with 192 cycles of radiation and cultured for 15 days. (4) Lenses exposed to 39.5°C for 2 hours 3 times with 24 hours interval after each treatment beginning on the second day of the culture and cultured for 11 days. During the culture period, lens optical quality was followed daily by a computer-operated scanning laser beam. At the end of the culture period, control and treated lenses were analyzed morphologically and by assessment of the lens epithelial ATPase activity. Exposure to 1.1 GHz, 2.22 mW microwaves caused a reversible decrease in lens optical quality accompanied by irreversible morphological and biochemical damage to the lens epithelial cell layer. The effect of the electromagnetic radiation on the lens epithelium was remarkably different from those of conductive heat. The results of this investigation showed that electromagnetic fields from microwave radiation have a negative impact on the eye lens. The lens damage by electromagnetic fields was distinctly different from that caused by conductive heat.

  17. Modifications of mitosis

    SciTech Connect

    1993-12-31

    Chapter 15, discusses modifications of mitosis, including endoreduplication, polyteny, endomitosis, C-mitosis, restitution, amitosis and multipolar mitoses. Apart from multipolar mitosis, all other mitotic modifications are characterized by an absent or defective spindle, and in most cases these result in the duplication of the chromosome number. 29 refs., 4 figs.

  18. Permit application modifications

    SciTech Connect

    1995-11-01

    This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils.

  19. Lifestyle modifications for GDM.

    PubMed

    Dhingra, Atul; Ahuja, Kamlesh

    2016-09-01

    Prevalence of gestational diabetes mellitus (GDM) is increasing worldwide more so in Southeast Asian countries like India and Pakistan. 1 GDM is associated with various adverse foetal and maternal effects. The management of GDM aims at reducing blood glucose to reduce maternal and foetal morbidity and mortality. Various studies have shown that lifestyle modifications are an important tool for reducing blood glucose levels in patients with GDM. Lifestyle modifications consist of dietary modifications and daily physical activity. Dietary modifications aim to achieve glycaemic control by providing adequate calories to the mother and foetus. Exercise is an obvious adjunct to dietary modifications for management of GDM. Therefore the purpose of this review is to summarize the benefits of lifestyle interventions in patients with GDM. PMID:27582149

  20. Conditional inactivation of p53 in mouse ovarian surface epithelium does not alter MIS driven Smad2-dominant negative epithelium-lined inclusion cysts or teratomas.

    PubMed

    Quartuccio, Suzanne M; Lantvit, Daniel D; Bosland, Maarten C; Burdette, Joanna E

    2013-01-01

    Epithelial ovarian cancer is the most lethal gynecological malignancy among US women. The etiology of this disease, although poorly understood, may involve the ovarian surface epithelium or the epithelium of the fallopian tube fimbriae as the progenitor cell. Disruptions in the transforming growth factor beta (TGFβ) pathway and p53 are frequently found in chemotherapy-resistant serous ovarian tumors. Transgenic mice expressing a dominant negative form of Smad2 (Smad2DN), a downstream transcription factor of the TGFβ signaling pathway, targeted to tissues of the reproductive tract were created on a FVB background. These mice developed epithelium-lined inclusion cysts, a potential precursor lesion to ovarian cancer, which morphologically resembled oviductal epithelium but exhibited protein expression more closely resembling the ovarian surface epithelium. An additional genetic "hit" of p53 deletion was predicted to result in ovarian tumors. Tissue specific deletion of p53 in the ovaries and oviducts alone was attempted through intrabursal or intraoviductal injection of Cre-recombinase expressing adenovirus (AdCreGFP) into p53 (flox/flox) mice. Ovarian bursal cysts were detected in some mice 6 months after intrabursal injection. No pathological abnormalities were detected in mice with intraoviductal injections, which may be related to decreased infectivity of the oviductal epithelium with adenovirus as compared to the ovarian surface epithelium. Bitransgenic mice, expressing both the Smad2DN transgene and p53 (flox/flox), were then exposed to AdCreGFP in the bursa and oviductal lumen. These mice did not develop any additional phenotypes. Exposure to AdCreGFP is not an effective methodology for conditional deletion of floxed genes in oviductal epithelium and tissue specific promoters should be employed in future mouse models of the disease. In addition, a novel phenotype was observed in mice with high expression of the Smad2DN transgene as validated through q

  1. Intermediate Filaments and Polarization in the Intestinal Epithelium

    PubMed Central

    Coch, Richard A.; Leube, Rudolf E.

    2016-01-01

    The cytoplasmic intermediate filament cytoskeleton provides a tissue-specific three-dimensional scaffolding with unique context-dependent organizational features. This is particularly apparent in the intestinal epithelium, in which the intermediate filament network is localized below the apical terminal web region and is anchored to the apical junction complex. This arrangement is conserved from the nematode Caenorhabditis elegans to humans. The review summarizes compositional, morphological and functional features of the polarized intermediate filament cytoskeleton in intestinal cells of nematodes and mammals. We emphasize the cross talk of intermediate filaments with the actin- and tubulin-based cytoskeleton. Possible links of the intermediate filament system to the distribution of apical membrane proteins and the cell polarity complex are highlighted. Finally, we discuss how these properties relate to the establishment and maintenance of polarity in the intestine. PMID:27429003

  2. Sugar expressions on the vaginal epithelium in pregnant mice.

    PubMed

    Yasunaga, Youhei; Takeuchi, Takashi; Shimokawa, Tetsuya; Nabeta, Motowo; Matsuu, Aya; Asano, Atsushi; Ohta, Yasuhiko

    2012-06-01

    Sugar expressions were examined on the epithelium of both the middle portion of the vagina and the vaginal portion of the cervical canal (CC) in pregnant mice to understand the pathogenesis of bacterial infection in the female reproductive organ by using a panel of lectins. As a result, N-acetylglucosamine was positive before pregnant day (P) 7 but negative after P10 and at diestrus on both the vagina and the CC. In addition, some differences in sugar expressions were seen between them. These results suggest that sugar expressions on the mucosal surface would change not only site-specifically but also time-dependently, and these sugar differences indicate the possibility of the alteration of the settled bacterial species on the vaginal mucosa in pregnancy.

  3. Abl suppresses cell extrusion and intercalation during epithelium folding.

    PubMed

    Jodoin, Jeanne N; Martin, Adam C

    2016-09-15

    Tissue morphogenesis requires control over cell shape changes and rearrangements. In the Drosophila mesoderm, linked epithelial cells apically constrict, without cell extrusion or intercalation, to fold the epithelium into a tube that will then undergo epithelial-to-mesenchymal transition (EMT). Apical constriction drives tissue folding or cell extrusion in different contexts, but the mechanisms that dictate the specific outcomes are poorly understood. Using live imaging, we found that Abelson (Abl) tyrosine kinase depletion causes apically constricting cells to undergo aberrant basal cell extrusion and cell intercalation. abl depletion disrupted apical-basal polarity and adherens junction organization in mesoderm cells, suggesting that extruding cells undergo premature EMT. The polarity loss was associated with abnormal basolateral contractile actomyosin and Enabled (Ena) accumulation. Depletion of the Abl effector Enabled (Ena) in abl-depleted embryos suppressed the abl phenotype, consistent with cell extrusion resulting from misregulated ena Our work provides new insight into how Abl loss and Ena misregulation promote cell extrusion and EMT.

  4. Cytoarchitectural changes in lens epithelium of galactose-fed rats.

    PubMed

    Gona, O

    1984-06-01

    Whole mounts of lens epithelia from rats fed on a galactose-rich diet for one, two, three or seven days were examined for morphological alterations. The meridional rows of epithelia from lenses of animals fed on galactose for seven days were found to be grossly disorganized or abnormally elongated. There was some indication that the cells were edematous and that the epithelium had become multilayered. These abnormalities apparently extended into the transitional zone. Evidence of the cytoarchitectural changes was present as early as one day after institution of the 30% galactose diet and progressed steadily over the period of observation. The findings provide support for the hypothesis that loss of meridional row integrity is a phenomenon common to development of most types of cortical cataracts.

  5. X-ray microanalysis of hamster tracheal epithelium

    SciTech Connect

    Spencer, A.J.; Roomans, G.M. )

    1989-06-01

    Studies of ion transport across respiratory epithelia are of great interest if we are to understand the pathophysiology of diseases such as cystic fibrosis in which ion transport is abnormal. Concentrations of elements were determined in various subcellular regions of normal or isoproterenol-treated hamster tracheal epithelium, using X-ray microanalysis of freeze-dried cryosections. Samples of trachea were taken from animals under anesthesia and either frozen in situ or dissected and plunge frozen. Concentrations of Mg, P, S, Cl, K and Ca were higher in cytoplasm and nuclei of control epithelial cells in dissected samples than in cryoneedle samples. Following treatment with isoproterenol, a large decrease in the concentration of Cl was observed. The results confirm that cyclic AMP-regulated chloride secretion is unaffected by anesthesia.

  6. Asymmetric ( UC)albumin transport across bullfrog alveolar epithelium

    SciTech Connect

    Kim, K.J.; LeBon, T.R.; Shinbane, J.S.; Crandall, E.D.

    1985-10-01

    Bullfrog lungs were prepared as planar sheets and bathed with Ringer solution in Ussing chambers. In the presence of a constant electrical gradient (20, 0, or -20 mV) across the tissue, UC-labeled bovine serum albumin or inulin was instilled into the upstream reservoir and the rate of appearance of the tracer in the downstream reservoir was monitored. Two lungs from the same animal were used to determine any directional difference in tracer fluxes. An apparent permeability coefficient was estimated from a relationship between normalized downstream radioactivities and time. Results showed that the apparent permeability of albumin in the alveolar to pleural direction across the alveolar epithelial barrier is 2.3 X 10(-7) cm/s, significantly greater (P less than 0.0005) than that in the pleural to alveolar direction (5.3 X 10(-8) cm/s) when the tissue was short circuited. Permeability of inulin, on the other hand, did not show any directional dependence and averaged 3.1 X 10(-8) cm/s in both directions. There was no effect on radiotracer fluxes permeabilities of different electrical gradients across the tissue. Gel electrophoretograms and corresponding radiochromatograms suggest that the large and asymmetric isotope fluxes are not primarily due to digestion or degradation of labeled molecules. Inulin appears to traverse the alveolar epithelial barrier by simple diffusion through hydrated paracellular pathways. On the other hand, ( UC)albumin crosses the alveolar epithelium more rapidly than would be expected by simple diffusion. These asymmetric and large tracer fluxes suggest that a specialized mechanism is present in alveolar epithelium that may be capable of helping to remove albumin from the alveolar space.

  7. Morphological and glycan features of the camel oviduct epithelium.

    PubMed

    Accogli, Gianluca; Monaco, Davide; El Bahrawy, Khalid Ahmed; El-Sayed, Ashraf Abd El-Halim; Ciannarella, Francesca; Beneult, Benedicte; Lacalandra, Giovanni Michele; Desantis, Salvatore

    2014-07-01

    This study describes regional differences in the oviduct of the one-humped camel (Camelus dromedarius) during the growth phase (GP) and the mature phase (MP) of the follicular wave by means of morphometry, scanning electron microscopy (SEM) and glycohistochemistry investigations. Epithelium height significantly increased in the ampulla and decreased in the isthmus passing from the GP to the MP. Under SEM, non-ciliated cells displayed apical blebs (secretory) or short microvilli. Cilia glycocalyx expressed glycans terminating with sialic acid linked α2,6 to Gal/GalNAc (SNA affinity) throughout the oviducts of GP and MP and sialic acid linked α2,3 to Galβ1,3GalNAc (MAL II and KOH-sialidase (K-s)-PNA staining) throughout the MP oviducts. Non-ciliated cells displayed lectin-binding sites from the supra-nuclear cytoplasm to the luminal surface. Ampulla non-ciliated cells showed O-linked (mucin-type) sialoglycans (MAL II and K-s-PNA) during GP and MP and N-linked sialoglycans (SNA) during the MP. Isthmus non-ciliated cells expressed SNA reactivity in GP and MP, also K-s-PNA binders in MP, and MAL II and PNA affinity (Galβ1,3GalNAc) during GP. Galβ1,3GalNAc was sialilated in the non-ciliated cells of GP UTJ. Luminal surface lacked of Galβ1,3GalNAc in GP and MP, whereas it expressed α2,6- and α2,3-linked sialic acids. In GP intraluminal substance reacted with SNA, MAL II, K-s-PNA in ampulla and only with MAL II in the isthmus and UTJ. These results demonstrate that the morphology and the glycan pattern of the camel oviductal epithelium vary during the follicular wave and that could relate to the region-specific functions.

  8. Alterations in phenotypic biochemical markers in bladder epithelium during tumorigenesis.

    PubMed

    Rao, J Y; Hemstreet, G P; Hurst, R E; Bonner, R B; Jones, P L; Min, K W; Fradet, Y

    1993-09-01

    Phenotypic biochemical markers of oncogenesis and differentiation were mapped in bladder biopsies to investigate changes that occur in bladder tumorigenesis and to identify markers for increased bladder cancer risk. Touch preparations from biopsy specimens from 30 patients were obtained from tumors, the adjacent bladder epithelium, and random distant bladder epithelium. Markers, including DNA ploidy, epidermal growth factor receptor (EGFR), and oncoproteins, were quantified in individual cells by using quantitative fluorescence image analysis. Cluster analysis revealed the markers fell into three independent groups: (i) G-actin and EGFR; (ii) ploidy, cytology, and p185 (HER-2/neu oncoprotein) (ERBB2); and (iii) p300, a low-grade tumor antigen. Each marker displayed a gradient of abnormality from distant field to adjacent field to tumor. Different patterns for each marker suggested a developmental sequence of bladder cancer oncogenesis; G-actin was altered in 58% of distant biopsies (vs. 0/6 normals, P < 0.001), ploidy and cytology were altered in < 20% of distant fields and approximately 80% of tumors, and the other markers were intermediate. Patterns of EGFR and p185 suggest low-and high-grade tracks diverge early (P < 0.05 by Mann-Whitney U test for EGFR and ANOVA for p185). In conclusion, this study shows that a sequence of phenotypic changes accompanies development and progression of bladder cancers. Biochemical alterations in cells of the bladder field are often detectable before abnormal pathology, and markers previously thought to be limited to tumors were found in the field. The hierarchy of expression may be useful in identifying high-risk patients, assessing completeness of response to therapy, and monitoring and predicting recurrence. PMID:8367495

  9. The role of lens epithelium in sugar cataract formation.

    PubMed

    Robison, W G; Houlder, N; Kinoshita, J H

    1990-06-01

    Previous evidence has shown clearly that sugar cataract formation results from unusually high intracellular levels of polyol. Documentation of polyol-related histological changes in the cortical fiber cells of the equatorial zone has been extensive. However, little attention has been given to the early changes in the lens epithelial cells, in spite of the fact that the highest level of aldose reductase is found in this layer of the lens. Also, cultured lens epithelial cells exposed to high sugar levels exhibit rapid accumulation of polyol and show ultrastructural alterations. Therefore, a study was designed to evaluate the role of the lens epithelium in sugar cataract formation. Specifically, an attempt was made to localize the earliest fine structural lesions in intact lenses of galactose-fed rats and to test their relation to aldose reductase. Rats were fed either a normal diet or a 50% galactose diet with or without sorbinil, an aldose reductase inhibitor. Rats were killed at varying periods of time ranging from 6 to 96 hr, and the eyes were processed for light and electron microscopy. The first detectable abnormalities occurred after 36 hr of galactose feeding, and were limited to the central lens epithelium. Cell edema, apparent dilution of cytoplasm, rounding of nuclei, aberrant intracellular vacuoles, and loss of normal tortuosity of cell boundaries were the salient lesions. No changes were detectable in the equatorial zone until 48 hr, and no deviation from the control structure was found in any of the rats treated with an aldose reductase inhibitor.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Quantification of PCNA+ cells within odontogenic jaw cyst epithelium.

    PubMed

    Li, T J; Browne, R M; Matthews, J B

    1994-04-01

    The aim of this study was to investigate the reactivity of the epithelial linings of the three major types of odontogenic cyst with a monoclonal antibody to proliferating cell nuclear antigen (PCNA; clone PC10). PCNA expression was studied in odontogenic cysts (n = 31) and normal oral epithelium (n = 10) using a biotin-streptavidin method on routinely processed paraffin sections. PCNA+ cells were counted manually and related to the length of basement membrane (mm) and the epithelial area (mm2) as determined by TV image analysis. The epithelial linings of odontogenic keratocysts (OKC; n = 11) contained the highest number of PCNA+ cells, most of which were located in the suprabasal layers. The mean value of PCNA+ cells in OKC linings (94.4 +/- 22.7 cells/mm) was similar to that of oral epithelia (80.8 +/- 20.6 cells/mm), but both were significantly higher than that of dentigerous (n = 10, 5.1 +/- 3.0 cells/mm) and radicular (n = 10, 11.0 +/- 4.1 cells/mm) cyst linings (P < 0.005). The epithelial distribution of PCNA+ cells differed between groups with the basal/suprabasal PCNA+ cell ratio in OKC linings (0.05 +/- 0.02) being significantly lower than that of normal oral epithelium (0.5 +/- 0.14), dentigerous (1.6 +/- 1.23) and radicular (1.9 +/- 1.09) cyst linings respectively (P < 0.005). These results demonstrate differences in PCNA expression between the epithelial linings of the major odontogenic cyst types, indicating differences in proliferative and differentiation processes within these lesions.

  11. NORMAL GENE EXPRESSION IN MALE F344 RAT NASAL TRANSITIONAL/RESPIRATORY EPITHELIUM

    EPA Science Inventory

    Abstract

    The nasal epithelium is an important target site for chemically-induced toxicity and carcinogenicity in rodents. Gene expression profiles were determined in order to provide normal baseline data for nasal transitional/respiratory epithelium from healthy rats. Ce...

  12. Denervation resulting in dento-alveolar ankylosis associated with decreased Malassez epithelium.

    PubMed

    Fujiyama, K; Yamashiro, T; Fukunaga, T; Balam, T A; Zheng, L; Takano-Yamamoto, T

    2004-08-01

    Inferior alveolar nerve denervation causes appreciable decreases in the distribution of epithelial rests of Malassez. To explore roles of the Malassez epithelium, we attempted to evaluate possible changes in dento-alveolar tissues surrounding this epithelium by experimental denervation. We found that denervation led to dento-alveolar ankylosis with a decrease in the width of the periodontal spaces. Interestingly, with regeneration of the Malassez epithelium 10 weeks after the denervation, the periodontal space width showed a correspondingly significant increase. These findings suggest that the Malassez epithelium may be involved in the maintenance of periodontal space and that sensory innervation might be indirectly associated with it. In addition, it is of interest that denervation activated root resorption of the coronal root surface and that the consequently resorbed lacunae were repaired by cellular cementum. It is suggested that Malassez epithelium may negatively regulate root resorption and induce acellular cementum formation. PMID:15271971

  13. Transglutaminase-Mediated Modifications of the Rat Sperm Surface in vitro

    NASA Astrophysics Data System (ADS)

    Paonessa, G.; Metafora, S.; Tajana, G.; Abrescia, P.; de Santis, A.; Gentile, V.; Porta, R.

    1984-11-01

    Two transglutaminase-mediated modifications of the rat epididymal spermatozoon surface were demonstrated in vitro. Transglutaminase was effective in promoting the binding of spermidine to the sperm. Moreover, the enzyme, by reacting with one of the major proteins secreted by the rat seminal vesicle epithelium, produced a modified form of the protein with a higher molecular weight and the capability of binding to the sperm cells. A specific physiological role for the enzyme, bringing about modifications of the rat sperm surface in the seminal fluid environment, is suggested.

  14. Jackson Creek Spillway modifications

    SciTech Connect

    Freitas, M.J.; Young, D.J.; McCloud, B.J.

    1995-12-31

    The Jackson Creek Spillway in Amador County, California has been modified in response to issues raised during the Federal Energy Regulatory Commission (FERC) mandated 5-year safety inspections. The calculated factors of safety for the Jackson Creek Spillway, under the probable maximum flood (PMF) and maximum credible earthquake (MCE) loading conditions, were below levels considered acceptable by the FERC and modifications to the structure were required. Woodward-Clyde Consultants, under contract to the East Bay Municipal Utility District (EBMUD), designed the modifications and in the summer and fall of 1994 the modifications to the Jackson Creek Spillway were successfully constructed with both FERC and California Division of Safety of Dams (DSOD) approval. This paper will summarize the design and construction issues, and discuss the lessons learned during modification of this 67-year-old structure.

  15. Interactions of organophosphates with keratins in the cornified epithelium of human skin.

    PubMed

    Verstappen, Daan R W; Hulst, Albert G; Fidder, Alex; Vermeulen, Nico P E; Noort, Daan

    2012-05-30

    Methods to unequivocally assess and quantify exposure to organophosphate anti-cholinesterase agents are highly valuable, either from a biomonitoring or a forensic perspective. Since for both OP pesticides and various nerve agents the skin is a predominant route of entry, we hypothesized that proteins in the skin might represent an ideal source of unequivocal and persistent biomarkers for exposure to these compounds. In this exploratory study we show that keratin proteins in human skin are relevant binding sites for organophosphates. The thick cornified epithelium of human plantar skin (callus) was exposed to a selection of relevant organophosphorus compounds and keratin proteins were subsequently extracted. After carboxymethylation of cysteine residues, enzymatic digestion of the keratins with pronase and trypsin was performed and the resulting amino acid and peptides were analyzed to assess whether covalent adducts had formed. LC-tandem MS analysis of the pronase digests demonstrated that tyrosine and to a lesser extent serine residues were selectively modified by organophosphate pesticides (both phosphorothioates and the corresponding oxon forms) under physiological conditions. In addition, modification of tyrosine with the nerve agent VX was unequivocally assessed. In order to elucidate specific binding sites, LC-tandem MS analysis of trypsin digests showed two separate tryptic keratin fragments, i.e. LASY*LDK and SLY*GLGGSK, with Y* the modified tyrosine residues, originating from keratin 1/6 and keratin 10, respectively. These preliminary findings, revealing novel binding targets for anti-cholinesterase organophosphates, will form a firm basis for the development of novel (non-invasive) methods for assessment of exposure to organophosphates. Whether this binding will also have biological implications remains an issue for further investigations.

  16. Simple epithelium keratins are required for maintenance of hepatocyte integrity.

    PubMed Central

    Loranger, A.; Duclos, S.; Grenier, A.; Price, J.; Wilson-Heiner, M.; Baribault, H.; Marceau, N.

    1997-01-01

    Keratin 8 (K8)-deficient adult mice develop a severe disease of the gastrointestinal tract characterized mainly by colorectal hyperplasia and inflammation. Given that hepatocytes contain K8/K18 heteropolymers only, this animal model was used to assess the contribution of these simple epithelium keratins to hepatocyte structural and functional integrity. Homozygous mutant (HMZ), heterozygous, and wild-type (WT) mice were examined for hepatocyte structural and metabolic features and their survival to partial hepatectomy. Except for the presence of few necrotic foci, no other tissular or cellular alterations were observed in nonhepatectomized HMZ mouse livers; glycogen and lipid peroxidation levels were essentially normal, but a small reduction in bile flow was observed. In response to a single pentobarbital injection, HMZ mice had longer sleeping times than heterozygous and WT mice. After a two-thirds partial hepatectomy under pentobarbital anesthesia, all HMZ mice died within a few hours, whereas those anesthetized with ether survived for 1 to 2 days. One hour after hepatectomy after pentobarbital anesthesia, many hepatocytes contained erythrocytes and large vacuoles in the cytoplasm, which suggests damage at the plasma membrane level in response to a sudden increase in portal blood flow. In line with these findings, an uptake of trypan blue by HMZ but not WT mouse hepatocytes was observed during a 10 ml/minute perfusion via the portal vein with a dye-supplemented buffer. Subsequent cellular dispersion led to viable WT mouse hepatocytes but largely nonviable HMZ mouse hepatocytes. Better viability was obtained at lower perfusion rates. Partially hepatectomized heterozygous mice developed liver steatosis, a condition that was not associated with a change in K8 content but perhaps linked to the presence of the neo gene. Transgenic HMZ mouse rescue experiments with a full-length K8 gene confirmed that the phenotypic alterations observed in partially hepatectomized HMZ

  17. Development of an electrode for the artificial cochlear sensory epithelium.

    PubMed

    Tona, Yosuke; Inaoka, Takatoshi; Ito, Juichi; Kawano, Satoyuki; Nakagawa, Takayuki

    2015-12-01

    An artificial cochlear sensory epithelium has been developed on the basis of a new concept that the piezoelectric membrane, which converts mechanical distortion into electricity, can mimic the function of the inner hair cell and basilar membrane of the mammalian cochlea. Our previous research demonstrated that the piezoelectric membrane generated electrical outputs in response to the sound stimulation after implantation into the guinea pig cochlea, whereas electrodes for the stimulation of spiral ganglion neurons have not been fabricated, and a method to fix the device in the cochlea is also required to show proof-of-concept. In the present study, to achieve proof-of-concept of hearing recovery by implantation of the artificial cochlear sensory epithelium, we fabricated new electrodes that stick into the cochlear modiolus, which also play a role in the fixation of the device in the cochlea. The efficacy of new electrodes for fixation of the device in the cochlea and for the stimulation of spiral ganglion neurons was estimated in guinea pigs. Four weeks after implantation, we confirmed that the devices were in place. Histological analysis of the implanted cochleae revealed inconspicuous fibrosis and scar formation compared with the sham-operated specimens (n = 5 for each). The terminal deoxynucleotidyl transferase dUTP nick end labeling method was used to assess cell death due to surgical procedures in the cochleae that were harvested after 1 day (n = 6) and 7 days (n = 6) of implantation; there was no significant increase in apoptotic cell death in the implanted cochleae compared with sham-operated cochleae. In seven animals, serial measurements of electrically evoked auditory brainstem responses were obtained, with the electrode positioned in the scala tympani and with the electrode inserted into the cochlear modiolus. With the insertion of electrodes into the cochlear modiolus, significant reduction was achieved in the thresholds of electrically evoked auditory

  18. Intranasal Location and Immunohistochemical Characterization of the Equine Olfactory Epithelium

    PubMed Central

    Kupke, Alexandra; Wenisch, Sabine; Failing, Klaus; Herden, Christiane

    2016-01-01

    The olfactory epithelium (OE) is the only body site where neurons contact directly the environment and are therefore exposed to a broad variation of substances and insults. It can serve as portal of entry for neurotropic viruses which spread via the olfactory pathway to the central nervous system. For horses, it has been proposed and concluded mainly from rodent studies that different viruses, e.g., Borna disease virus, equine herpesvirus 1 (EHV-1), hendra virus, influenza virus, rabies virus, vesicular stomatitis virus can use this route. However, little is yet known about cytoarchitecture, protein expression and the intranasal location of the equine OE. Revealing differences in cytoarchitecture or protein expression pattern in comparison to rodents, canines, or humans might help to explain varying susceptibility to certain intranasal virus infections. On the other hand, disclosing similarities especially between rodents and other species, e.g., horses would help to underscore transferability of rodent models. Analysis of the complete noses of five adult horses revealed that in the equine OE two epithelial subtypes with distinct marker expression exist, designated as types a and b which resemble those previously described in dogs. Detailed statistical analysis was carried out to confirm the results obtained on the descriptive level. The equine OE was predominantly located in caudodorsal areas of the nasal turbinates with a significant decline in rostroventral direction, especially for type a. Immunohistochemically, olfactory marker protein and doublecortin (DCX) expression was found in more cells of OE type a, whereas expression of proliferating cell nuclear antigen and tropomyosin receptor kinase A was present in more cells of type b. Accordingly, type a resembles the mature epithelium, in contrast to the more juvenile type b. Protein expression profile was comparable to canine and rodent OE but equine types a and b were located differently within the nose and

  19. Human Rights and Behavior Modification

    ERIC Educational Resources Information Center

    Roos, Philip

    1974-01-01

    Criticisms of behavior modification, which charge that it violates ethical and legal principles, are discussed and reasons are presented to explain behavior modification's susceptibility to attack. (GW)

  20. Airway responsiveness: role of inflammation, epithelium damage and smooth muscle tension.

    PubMed

    Gourgoulianis, K I; Domali, A; Molyvdas, P A

    1999-01-01

    The purpose of this study was the effect of epithelium damage on mechanical responses of airway smooth muscles under different resting tension. We performed acetylcholine (ACh) (10(-5) M)-induced contraction on tracheal strips from 30 rabbits in five groups (0.5, 1, 1.5, 2 and 2.5 g) before and after epithelium removal. At low resting tension (0.5-1.5 g), the epithelium removal decreased the ACh-induced contractions. At 2 g resting tension, the epithelium removal increased the ACh-induced contractions of airways with intact epithelium about 20%. At 2.5 g resting tension, the elevation of contraction is about 25% (P<0.01). Consequently, after epithelium loss, the resting tension determines the airway smooth muscles responsiveness. In asthma, mediators such as ACh act on already contracted inflammatory airways, which results in additional increase of contraction. In contrast, low resting tension, a condition that simulates normal tidal breathing, protects from bronchoconstriction even when the epithelium is damaged. PMID:10704081

  1. Absorption and exchange of water across rumen epithelium.

    PubMed

    Dobson, A; Sellers, A F; Gatewood, V H

    1976-11-01

    The osmotic pressure of solutions in the ventral sac of the rumen of the conscious cow was varied with Na Cl or mannitol. The mucosal blood flow measured by HTO clearance was minimal when the lumen contained an isotonic solution and rose threefold when the rumen was hypo- or hypertonic to plasma by 150 mosmol/kg. Thus osmotic gradients actoss the rumen epithelium stimulated mucosal blood flow. Using osmotic gradients small enough to avoid blood flow stimulation, the net water flow could be enhanced by butyrate, a chemical stimulator of blood flow. Thus water movement was partially limited by blood flow. This implied an appreciable change in osmotic pressure of the capillary blood toward that of the rumen contents. The relative importance of blood flow, membrane permeability, and solute uptake on water transport was assessed. The osmotic pressure in the rumen was stationary when the rumen solution was distinctly hypotonic to plasma. The absorbate in the absence of an osmotic gradient was thus hypertonic. The net uptake of solute increased rapidly when the solution in the lumen was hypertonic to plasma. This gave rise to a more rapid rate of change of osmotic pressure in the rumen under this condition.

  2. Sulfate transport in apical membrane vesicles isolated from tracheal epithelium

    SciTech Connect

    Elgavish, A.; DiBona, D.R.; Norton, P.; Meezan, E.

    1987-09-01

    Sulfate uptake in apical membrane vesicles isolated from bovine tracheal epithelium is shown to occur into an osmotically sensitive intravesicular space, via a carrier-mediated system. This conclusion is based on three lines of evidence: 1) saturation kinetics: 2) substrate specificity; and 3) inhibition by the anion transport inhibitors SITS and DIDS. The affinity of the transport system is highest in low ionic strength media and decreases in the presence of gluconate. Chloride appears to cis-inhibit sulfate uptake and to trans-stimulate sulfate efflux. Cis-inhibition and trans-stimulation studies with a variety of anions indicate that this exchange system may be shared by HCO/sub 3//sup -/, S/sub 2/O/sub 3//sup 2 -/, SeO/sub 4//sup 2 -/, and MoO/sub 4//sup 2 -/ but not by H/sub 2/PO/sub 4//sup -/ or HAsO/sub 4//sup 2/. Studies indicate that protons may play two distinct roles in sulfate transport in this system. These studies show that the carrier-mediated system can function in the absence of chloride. The overshoot observed in the presence of a proton gradient indicates that under those conditions the mechanism of transport may be a SO/sub 4//sup 2 -/-OH/sup -/ exchange.

  3. In vitro function of cyst epithelium from human polycystic kidney.

    PubMed Central

    Perrone, R D

    1985-01-01

    It is thought that cysts in polycystic kidneys originate from nephron segments and function in a manner similar to the segment or origin. The indirect evidence for this derives from studies of microanatomy and cyst fluid composition. Cysts with low Na+ have been classified as distal, whereas cysts with high Na+ have been classified as proximal. In order to directly determine the transport characteristics of cyst epithelium, cysts from a human polycystic kidney were studied in vitro using Ussing chamber techniques. Composition of cyst fluid was determined in parallel with these studies. Cysts with low Na+ (gradient cysts) demonstrate characteristics consistent with distal nephron origin including elevated potential difference (PD), short-circuit current (Isc), and low conductance. PD and Isc of gradient cysts were amiloride sensitive. Nongradient cysts, however, require additional characterization. At least two types of nongradient cysts were identified, one with characteristics consistent with proximal nephron origin and another apparently without function. These studies are the first direct evidence for active transport of cysts from human polycystic kidney and provide strong evidence to support the concept that cysts function in the same manner as the nephron segment of origin. PMID:4056045

  4. Retinal pigment epithelium transplantation: concepts, challenges, and future prospects

    PubMed Central

    Alexander, P; Thomson, H A J; Luff, A J; Lotery, A J

    2015-01-01

    The retinal pigment epithelium (RPE) is a single layer of cells that supports the light-sensitive photoreceptor cells that are essential for retinal function. Age-related macular degeneration (AMD) is a leading cause of visual impairment, and the primary pathogenic mechanism is thought to arise in the RPE layer. RPE cell structure and function are well understood, the cells are readily sustainable in laboratory culture and, unlike other cell types within the retina, RPE cells do not require synaptic connections to perform their role. These factors, together with the relative ease of outer retinal imaging, make RPE cells an attractive target for cell transplantation compared with other cell types in the retina or central nervous system. Seminal experiments in rats with an inherited RPE dystrophy have demonstrated that RPE transplantation can prevent photoreceptor loss and maintain visual function. This review provides an update on the progress made so far on RPE transplantation in human eyes, outlines potential sources of donor cells, and describes the technical and surgical challenges faced by the transplanting surgeon. Recent advances in the understanding of pluripotent stem cells, combined with novel surgical instrumentation, hold considerable promise, and support the concept of RPE transplantation as a regenerative strategy in AMD. PMID:26043704

  5. Retinal pigment epithelium transplantation: concepts, challenges, and future prospects.

    PubMed

    Alexander, P; Thomson, H A J; Luff, A J; Lotery, A J

    2015-08-01

    The retinal pigment epithelium (RPE) is a single layer of cells that supports the light-sensitive photoreceptor cells that are essential for retinal function. Age-related macular degeneration (AMD) is a leading cause of visual impairment, and the primary pathogenic mechanism is thought to arise in the RPE layer. RPE cell structure and function are well understood, the cells are readily sustainable in laboratory culture and, unlike other cell types within the retina, RPE cells do not require synaptic connections to perform their role. These factors, together with the relative ease of outer retinal imaging, make RPE cells an attractive target for cell transplantation compared with other cell types in the retina or central nervous system. Seminal experiments in rats with an inherited RPE dystrophy have demonstrated that RPE transplantation can prevent photoreceptor loss and maintain visual function. This review provides an update on the progress made so far on RPE transplantation in human eyes, outlines potential sources of donor cells, and describes the technical and surgical challenges faced by the transplanting surgeon. Recent advances in the understanding of pluripotent stem cells, combined with novel surgical instrumentation, hold considerable promise, and support the concept of RPE transplantation as a regenerative strategy in AMD. PMID:26043704

  6. Development of rumen metabolism and ruminal epithelium in lambs.

    PubMed

    Zitnan, R; Bomba, A; Sommer, A; Kolodzieyski, L

    1993-01-01

    The concentrations of volatile fatty acids and the development of rumen epithelium and microflora adhered to rumen wall in suckling lambs were observed. Total VFA concentration increased with age. The differences between the 1st (28.5 mmol.l-1) and 4th week of age (78.7 mmol.l-1) and between 6th (82.1 mmol.l-1 and 10th week of age (117.4 mmol.l-1) were significant (p < 0.01). The highest molar proportion of acetic acid (71.2 mol%) was observed in 1 week-old lambs and the highest molar proportion of propionic acid in 6 week-old lambs (20.8 mol%). Length and surface characteristics of papillae changed dramatically over the 10-week period. In samples from 1-week and 4-week-old lambs, the papilla surface was relatively smooth and epithelial cells were relatively thin and flat. In samples from 6-week and 10-week-old lambs the tissue topography was typically rough. In the 1-week-old lambs the cocci, single rods and short rods in pairs were present at very low population levels. At 4 weeks the epimural community became notably more complex and bacteria were present at a higher population level. The dominant morphotype at 6 weeks was a rod-shaped end-on attached bacterium. The epimural microflora became the most complex at 10 weeks.

  7. The antiepileptic drug carbamazepine affects sodium transport in toad epithelium.

    PubMed

    Suwalsky, Mario; Mennickent, Sigrid; Norris, Beryl; Cardenas, Hernán

    2006-09-01

    The present work investigates the effects of the antiepileptic drug carbamazepine (CBZ) on sodium transport in the isolated skin of the toad Pleurodema thaul. A submaximal concentration of the drug (0.2 mM) applied to the outer surface of the epithelium increased the electrical parameters short-circuit current (Isc) and potential difference (PD) by over 28%, whereas only a higher concentration (1 mM) induced over a 45% decrease in these parameters when applied to the inner surface. The amiloride test showed that the outer surface stimulatory effect was accompanied by an increase and the inner surface inhibitory effect by a decrease in the sodium electromotive force (ENa). Exploration of these effects of CBZ on the outer surface showed that 0.2 mM increased net Na+ (22Na) influx by 20% and 0.6 mM CBZ decreased Na+ mucosa-serosa flux by 19%, a result in agreement with the finding that higher concentrations of CBZ applied to the inner surface not only decreased ENa but also sodium conductance (GNa). PMID:16542818

  8. The antiepileptic drug phenytoin affects sodium transport in toad epithelium.

    PubMed

    Suwalsky, Mario; Mennickent, Sigrid; Norris, Beryl; Cárdenas, Hernan

    2006-01-01

    The effects of phenytoin on isolated Pleurodema thaul toad skin were investigated. Low (micromolar) concentrations of the antiepileptic agent applied to the outside surface of the toad epithelium increased the electrical parameters (short-circuit current and potential difference) by over 40%, reflecting stimulation of Na(+) transport, whereas higher (millimolar concentrations, outside and inside surface) decreased both electric parameters, the effect being greater at the inside surface (40% and 80% decrease, respectively). The amiloride test showed that the stimulatory effect was accompanied by an increase and the inhibitory effect by a decrease in the sodium electromotive force (ENa). It is concluded that the drug interaction with membrane lipid bilayers might result in a distortion of the lipid-protein interface contributing to disturbance of Na(+) epithelial channel activity. After applying the Na(+)-K(+)-ATPase blocker ouabain and replacing the Na(+) ions in the outer Ringer's solution by choline, it was concluded that both active and passive transport are involved in sodium absorption, although active transport predominates. PMID:16314149

  9. Transcriptional regulatory network during development in the olfactory epithelium

    PubMed Central

    Im, SeungYeong; Moon, Cheil

    2015-01-01

    Regeneration, a process of reconstitution of the entire tissue, occurs throughout life in the olfactory epithelium (OE). Regeneration of OE consists of several stages: proliferation of progenitors, cell fate determination between neuronal and non-neuronal lineages, their differentiation and maturation. How the differentiated cell types that comprise the OE are regenerated, is one of the central questions in olfactory developmental neurobiology. The past decade has witnessed considerable progress regarding the regulation of transcription factors (TFs) involved in the remarkable regenerative potential of OE. Here, we review current state of knowledge of the transcriptional regulatory networks that are powerful modulators of the acquisition and maintenance of developmental stages during regeneration in the OE. Advance in our understanding of regeneration will not only shed light on the basic principles of adult plasticity of cell identity, but may also lead to new approaches for using stem cells and reprogramming after injury or degenerative neurological diseases. [BMB Reports 2015; 48(11): 599-608] PMID:26303973

  10. Role of Epithelium Sodium Channel in Bone Formation

    PubMed Central

    Wang, Ruo-Yu; Yang, Shu-Hua; Xu, Wei-Hua

    2016-01-01

    Objective: To review the recent developments in the mechanisms of epithelium sodium channels (ENaCs) induced bone formation and regulation. Data Sources: Studies written in English or Chinese were searched using Medline, PubMed and the index of Chinese-language literature with time restriction from 2005 to 2014. Keywords included ENaC, bone, bone formation, osteonecrosis, estrogen, and osteoporosis. Data from published articles about the structure of ENaC, mechanism of ENaC in bone formation in recent domestic and foreign literature were selected. Study Selection: Abstract and full text of all studies were required to obtain. Studies those were not accessible and those did not focus on the keywords were excluded. Results: ENaCs are tripolymer ion channels which are assembled from homologous α, β, and γ subunits. Crystal structure of ENaCs suggests that ENaC has a central ion-channel located in the central symmetry axis of the three subunits. ENaCs are protease sensitive channels whose iron-channel activity is regulated by the proteolytic reaction. Channel opening probability of ENaCs is regulated by proteinases, mechanical force, and shear stress. Several molecules are involved in regulation of ENaCs in bone formation, including nitride oxide synthases, voltage-sensitive calcium channels, and cyclooxygenase-2. Conclusion: The pathway of ENaC involved in shear stress has an effect on stimulating osteoblasts even bone formation by estrogen interference. PMID:26904995

  11. Chronic alcohol ingestion changes the landscape of the alveolar epithelium.

    PubMed

    Downs, Charles A; Trac, David; Brewer, Elizabeth M; Brown, Lou Ann; Helms, My N

    2013-01-01

    Similar to effects of alcohol on the heart, liver, and brain, the effects of ethanol (EtOH) on lung injury are preventable. Unlike other vital organ systems, however, the lethal effects of alcohol on the lung are underappreciated, perhaps because there are no signs of overt pulmonary disorder until a secondary insult, such as a bacterial infection or injury, occurs in the lung. This paper provides overview of the complex changes in the alveolar environment known to occur following both chronic and acute alcohol exposures. Contemporary animal and cell culture models for alcohol-induced lung dysfunction are discussed, with emphasis on the effect of alcohol on transepithelial transport processes, namely, epithelial sodium channel activity (ENaC). The cascading effect of tissue and phagocytic Nadph oxidase (Nox) may be triggered by ethanol exposure, and as such, alcohol ingestion and exposure lead to a prooxidative environment; thus impacting alveolar macrophage (AM) function and oxidative stress. A better understanding of how alcohol changes the landscape of the alveolar epithelium can lead to improvements in treating acute respiratory distress syndrome (ARDS) for which hospitalized alcoholics are at an increased risk. PMID:23509726

  12. Compensatory plasticity in the olfactory epithelium: age, timing, and reversibility

    PubMed Central

    Barber, Casey N.

    2015-01-01

    Like other biological systems, olfaction responds “homeostatically” to enduring change in the stimulus environment. This adaptive mechanism, referred to as compensatory plasticity, has been studied almost exclusively in developing animals. Thus it is unknown if this phenomenon is limited to ontogenesis and irreversible, characteristics common to some other forms of plasticity. Here we explore the effects of odor deprivation on the adult mouse olfactory epithelium (OE) using nasal plugs to eliminate nasal airflow unilaterally. Plugs were in place for 2–6 wk after which electroolfactograms (EOGs) were recorded from the occluded and open sides of the nasal cavity. Mean EOG amplitudes were significantly greater on the occluded than on the open side. The duration of plugging did not affect the results, suggesting that maximal compensation occurs within 2 wk or less. The magnitude of the EOG difference between the open and occluded side in plugged mice was comparable to adults that had undergone surgical naris occlusion as neonates. When plugs were removed after 4 wk followed by 2 wk of recovery, mean EOG amplitudes were not significantly different between the always-open and previously plugged sides of the nasal cavity suggesting that this form of plasticity is reversible. Taken together, these results suggest that compensatory plasticity is a constitutive mechanism of olfactory receptor neurons that allows these cells to recalibrate their stimulus-response relationship to fit the statistics of their current odor environment. PMID:26269548

  13. Histone Deacetylase Inhibition Restores Retinal Pigment Epithelium Function in Hyperglycemia

    PubMed Central

    Desjardins, Danielle; Liu, Yueying; Crosson, Craig E.; Ablonczy, Zsolt

    2016-01-01

    In diabetic individuals, macular edema is a major cause of vision loss. This condition is refractory to insulin therapy and has been attributed to metabolic memory. The retinal pigment epithelium (RPE) is central to maintaining fluid balance in the retina, and this function is compromised by the activation of advanced glycation end-product receptors (RAGE). Here we provide evidence that acute administration of the RAGE agonist, glycated-albumin (gAlb) or vascular endothelial growth factor (VEGF), increased histone deacetylase (HDAC) activity in RPE cells. The administration of the class I/II HDAC inhibitor, trichostatin-A (TSA), suppressed gAlb-induced reductions in RPE transepithelial resistance (in vitro) and fluid transport (in vivo). Systemic TSA also restored normal RPE fluid transport in rats with subchronic hyperglycemia. Both gAlb and VEGF increased HDAC activity and reduced acetyl-α-tubulin levels. Tubastatin-A, a relatively specific antagonist of HDAC6, inhibited gAlb-induced changes in RPE cell resistance. These data are consistent with the idea that RPE dysfunction following exposure to gAlb, VEGF, or hyperglycemia is associated with increased HDAC6 activity and decreased acetyl-α-tubulin. Therefore, we propose inhibiting HDAC6 in the RPE as a potential therapy for preserving normal fluid homeostasis in the hyperglycemic retina. PMID:27617745

  14. Keratinization of the esophageal epithelium of domesticated mammals.

    PubMed

    Meyer, Wilfried; Schoennagel, Britta; Kacza, Johannes; Busche, Roger; Hornickel, Isabelle Nina; Hewicker-Trautwein, Marion; Schnapper, Anke

    2014-01-01

    We studied the esophageal epithelium for keratinization characteristics from samples of domesticated mammals of three nutrition groups (herbivores: horse, cattle, sheep; omnivores: pig, dog, rat; carnivores: cat) using histochemistry (keratins, disulfides), sulfur measurements, and cryo-SEM. Keratins were found in all esophageal layers of all species, except for the equine Stratum corneum. The positive reaction staining of Pan-keratin was remarkable, but decreased in intensity toward the outer layers, whereas in the pig and cat, staining was confined to the corneal layer. The herbivores revealed positive staining reactions in the upper Stratum spinosum, particularly in the sheep. Regarding single keratins, CK6 immunostating was found in most esophageal layers, but only weakly or negatively in the porcine and equine Stratum corneum. CK13 staining was restricted to the sheep and here was found in all layers. CK14 could be detected in the equine and feline Stratum basale, and upper vital layers of the dog and rat. CK17 appeared only in the Stratum spinosum and Stratum granulosum, but in all layers of the dog and cat. Disulfides reacted strongest in the Stratum corneum of the herbivores, as corroborated by the sulfur concentrations in the esophagus. Our study emphasized that keratins are very important for the mechanical stability of the epithelial cells and cell layers of the mammalian esophagus. The role of these keratins in the esophageal epithelia is of specific interest owing to the varying feed qualities and mechanical loads of different nutrition groups, which have to be countered.

  15. [Epithelium constitution for esophageal tissue engineering using electrospinning technology].

    PubMed

    Chen, Ling; Lv, Jingjing; Yu, Xuechan; Kang, Cheng; Zhu, Yabin

    2013-12-01

    The basement membrane (BM) is crucial in regulating the physical and biological activities of esophageal epithelial cells which attach to the underlying BM. In order to simulate the natural construction of BM, we prepared the fibrous scaffolds using biodegradable polylactide (PLA) and silk fibroin (SF) as the materials via electrospinning technology. BM's proteins containing collagen (IV), laminin, entactin and proteoglycan were extracted from porcine esophagus and coated on the eletrospun fibers. Morphology, mechanical strength, biodegradability and cytocompatibility of the coated and uncoated scaffolds were tested and evaluated using scanning electron micrography, mechanical test system, immunofluorescence assay and western blotting with CK14 as the primary antibody. The fibrous scaffold PLA or PLA/SF, generated from the present protocol had good formation and mechanical and biodegradable properties. After coating with BM's proteins, the scaffold could enhance the growth and differentiation of esophageal epithelial cells, which would contribute to remodel and regenerate the tissue engineered epithelium and further contribute to engineer the whole esophagus in future.

  16. Histone Deacetylase Inhibition Restores Retinal Pigment Epithelium Function in Hyperglycemia.

    PubMed

    Desjardins, Danielle; Liu, Yueying; Crosson, Craig E; Ablonczy, Zsolt

    2016-01-01

    In diabetic individuals, macular edema is a major cause of vision loss. This condition is refractory to insulin therapy and has been attributed to metabolic memory. The retinal pigment epithelium (RPE) is central to maintaining fluid balance in the retina, and this function is compromised by the activation of advanced glycation end-product receptors (RAGE). Here we provide evidence that acute administration of the RAGE agonist, glycated-albumin (gAlb) or vascular endothelial growth factor (VEGF), increased histone deacetylase (HDAC) activity in RPE cells. The administration of the class I/II HDAC inhibitor, trichostatin-A (TSA), suppressed gAlb-induced reductions in RPE transepithelial resistance (in vitro) and fluid transport (in vivo). Systemic TSA also restored normal RPE fluid transport in rats with subchronic hyperglycemia. Both gAlb and VEGF increased HDAC activity and reduced acetyl-α-tubulin levels. Tubastatin-A, a relatively specific antagonist of HDAC6, inhibited gAlb-induced changes in RPE cell resistance. These data are consistent with the idea that RPE dysfunction following exposure to gAlb, VEGF, or hyperglycemia is associated with increased HDAC6 activity and decreased acetyl-α-tubulin. Therefore, we propose inhibiting HDAC6 in the RPE as a potential therapy for preserving normal fluid homeostasis in the hyperglycemic retina. PMID:27617745

  17. Proteinases of Pseudomonas aeruginosa evoke mucin release by tracheal epithelium.

    PubMed Central

    Klinger, J D; Tandler, B; Liedtke, C M; Boat, T F

    1984-01-01

    We have determined the potential of exoproducts from pathogenic bacteria to stimulate the release of high molecular weight mucins from goblet cells of airway epithelium in a rabbit tracheal explant system. Culture supernatants from proteolytic strains of Pseudomonas aeruginosa and Serratia marcescens, but not supernatants from a number of non-proteolytic strains, released mucins from goblet cells. Highly purified elastase and alkaline proteinase from P. aeruginosa stimulated goblet cell mucin release in a dose-dependent fashion. Lipopolysaccharide, exotoxin A, and alginate of P. aeruginosa did not possess mucin release properties. Proteolytic activity was required for mucin release by P. aeruginosa elastase, but such release in goblet cells was not mediated by cyclic AMP. Morphologic studies suggested rapid release of mucins from goblet cells was response to elastase by a process resembling apocrine secretion. Several nonbacterial proteinases mimicked the effect of Pseudomonas proteases. These studies provide support for the hypothesis that bacterial and other play a role in the pathogenesis of mucus hypersecretion in acute and chronic lung infections. Images PMID:6568227

  18. Molecular mechanism of ocular surface damage: Application to an in vitro dry eye model on human corneal epithelium

    PubMed Central

    De Servi, Barbara; Marasco, Daniela; Del Prete, Salvatore

    2011-01-01

    Purpose The present study was concerned with the development of a new experimental model of dry eye using human reconstructed in vitro corneal epithelium (HCE). The model is based on the use of adapted culture conditions that induce relevant modifications at the cellular and molecular level thus mimicking dry eye. Methods The HCE model was maintained in a controlled environmental setting (relative humidity <40% and 40 °C temperature) for 24 h and up to 72 h to induce dry eye. The evolution of the dry eye condition was assessed by histology, immunohistochemistry staining, scanning electron microscopy, and gene expression by using TaqMan gene assay technology (mucin-4 [MUC4], matrix metallopeptidase-9 [MMP9], tumor necrosis factor-α [TNF-α], and defensin β-2 [DEFB2). The effects of different commercially available tear substitutes on the induced dry eye condition were tested. Results This in vitro dry eye HCE model, that was well established within 24 h, has the characteristic features of a dry eye epithelium and could be satisfactorily used for preliminary assessment of the protective activity of some artificial tears. The transcriptional study of selected biomarkers showed an increase in MUC4, MMP9, TNF-α, and hBD-2 (DEFB2) gene expression. Conclusions By using a dynamic approach, we were able to define a biomarker gene signature of dry eye-induced effects that could be predictive of corneal damage in vivo and to discriminate the efficacy among different commercial artificial tears. PMID:21245952

  19. Modifications of gravity.

    PubMed

    Skordis, Constantinos

    2011-12-28

    General relativity (GR) is a phenomenologically successful theory that rests on firm foundations, but has not been tested on cosmological scales. The deep mystery of dark energy (and possibly even the requirement of cold dark matter (CDM)) has increased the need for testing modifications to GR, as the inference of such otherwise undetected fluids depends crucially on the theory of gravity. Here, I discuss a general scheme for constructing consistent and covariant modifications to the Einstein equations. This framework is such that there is a clear connection between the modification and the underlying field content that produces it. I argue that this is mandatory for distinguishing modifications of gravity from conventional fluids. I give a non-trivial example, a simple metric-based modification of the fluctuation equations for which the background is exact ΛCDM, but differs from it in the perturbations. I show how this can be generalized and solved in terms of two arbitrary functions. Finally, I discuss future prospects and directions of research.

  20. Readers of PCNA modifications.

    PubMed

    Ulrich, Helle D; Takahashi, Tomio

    2013-08-01

    The eukaryotic sliding clamp, proliferating cell nuclear antigen (PCNA), acts as a central coordinator of DNA transactions by providing a multivalent interaction surface for factors involved in DNA replication, repair, chromatin dynamics and cell cycle regulation. Posttranslational modifications (PTMs), such as mono- and polyubiquitylation, sumoylation, phosphorylation and acetylation, further expand the repertoire of PCNA's binding partners. These modifications affect PCNA's activity in the bypass of lesions during DNA replication, the regulation of alternative damage processing pathways such as homologous recombination and DNA interstrand cross-link repair, or impact on the stability of PCNA itself. In this review, we summarise our current knowledge about how the PTMs are "read" by downstream effector proteins that mediate the appropriate action. Given the variety of interaction partners responding to PCNA's modified forms, the ensemble of PCNA modifications serves as an instructive model for the study of biological signalling through PTMs in general. PMID:23580141

  1. Thyroid hormone responsive protein Spot14 enhances catalysis of fatty acid synthase in lactating mammary epithelium[S

    PubMed Central

    Rudolph, Michael C.; Wellberg, Elizabeth A.; Lewis, Andrew S.; Terrell, Kristina L.; Merz, Andrea L.; Maluf, N. Karl; Serkova, Natalie J.; Anderson, Steven M.

    2014-01-01

    Thyroid hormone responsive protein Spot 14 has been consistently associated with de novo fatty acid synthesis activity in multiple tissues, including the lactating mammary gland, which synthesizes large quantities of medium chain fatty acids (MCFAs) exclusively via FASN. However, the molecular function of Spot14 remains undefined during lactation. Spot14-null mice produce milk deficient in total triglyceride and de novo MCFA that does not sustain optimal neonatal growth. The lactation defect was rescued by provision of a high fat diet to the lactating dam. Transgenic mice overexpressing Spot14 in mammary epithelium produced total milk fat equivalent to controls, but with significantly greater MCFA. Spot14-null dams have no diminution of metabolic gene expression, enzyme protein levels, or intermediate metabolites that accounts for impaired de novo MCFA. When [13C] fatty acid products were quantified in vitro using crude cytosolic lysates, native FASN activity was 1.6-fold greater in control relative to Spot14-null lysates, and add back of Spot14 partially restored activity. Recombinant FASN catalysis increased 1.4-fold and C = 14:0 yield was enhanced 4-fold in vitro following addition of Spot14. These findings implicate Spot14 as a direct protein enhancer of FASN catalysis in the mammary gland during lactation when maximal MCFA production is needed. PMID:24771867

  2. Nose-to-Brain Delivery: Investigation of the Transport of Nanoparticles with Different Surface Characteristics and Sizes in Excised Porcine Olfactory Epithelium.

    PubMed

    Mistry, Alpesh; Stolnik, Snjezana; Illum, Lisbeth

    2015-08-01

    The ability to deliver therapeutically relevant amounts of drugs directly from the nasal cavity to the central nervous system to treat neurological diseases is dependent on the availability of efficient drug delivery systems. Increased delivery and/or therapeutic effect has been shown for drugs encapsulated in nanoparticles; however, the factors governing the transport of the drugs and/or the nanoparticles from the nasal cavity to the brain are not clear. The present study evaluates the potential transport of nanoparticles across the olfactory epithelium in relation to nanoparticle characteristics. Model systems, 20, 100, and 200 nm fluorescent carboxylated polystyrene (PS) nanoparticles that were nonmodified or surface modified with polysorbate 80 (P80-PS) or chitosan (C-PS), were assessed for transport across excised porcine olfactory epithelium mounted in a vertical Franz diffusion cell. Assessment of the nanoparticle content in the donor chamber of the diffusion cell, accompanied by fluorescence microscopy of dismounted tissues, revealed a loss of nanoparticle content from the donor suspension and their association with the excised tissue, depending on the surface properties and particle size. Chitosan surface modification of PS nanoparticles resulted in the highest tissue association among the tested systems, with the associated nanoparticles primarily located in the mucus, whereas the polysorbate 80-modified nanoparticles showed some penetration into the epithelial cell layer. Assessment of the bioelectrical properties, metabolic activity, and histology of the excised olfactory epithelium showed that C-PS nanoparticles applied in pH 6.0 buffer produced a damaging effect on the epithelial cell layer in a size-dependent manner, with fine 20 nm sized nanoparticles causing substantial tissue damage relative to that with the 100 and 200 nm counterparts. Although histology showed that the olfactory tissue was affected by the application of citrate buffer that was

  3. A morphological study of the tracheal epithelium of the snake Natrix maura.

    PubMed Central

    Pastor, L M

    1990-01-01

    The epithelium of the trachea of the Natrix maura snake was studied by conventional light microscopy and transmission and scanning electron microscopy. The epithelium is formed of basal, ciliated, endocrine and secretory cells. It shows different thickness and distribution of the cells, depending on the area (covering the cartilaginous or the membranous zone). Secretory cells show a morphology similar to that found in lizards but it is different from the mucous cells reported in the extrapulmonary airways of turtles, birds and mammals. The ultrastructure of the secretory cells is similar to that reported for serous cells in the airways of mammals. Intra-epithelial plasma cells are also found within the epithelium. The present results show that there are marked morphological differences between the tracheal epithelium of lizards and snakes and that of turtles, birds and mammals. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:2272908

  4. The ureteric bud epithelium: Morphogenesis and roles in metanephric kidney patterning

    PubMed Central

    Nagalakshmi, Vidya K.; Yu, Jing

    2015-01-01

    The mammalian metanephric kidney is composed of two epithelial components –the collecting duct system and the nephron epithelium– that differentiate from two different tissues –the ureteric bud epithelium and the nephron progenitors, respectively– of intermediate mesoderm origin. The collecting duct system is generated through reiterative ureteric bud branching morphogenesis whereas the nephron epithelium is formed in a process termed nephrogenesis, which is initiated with the mesenchymal-epithelial transition of the nephron progenitors. Ureteric bud branching morphogenesis is regulated by nephron progenitors, and in return the ureteric bud epithelium regulates nephrogenesis. The metanephric kidney is also physiologically divided along the cortico-medullary axis into subcompartments that are enriched with specific segments of these two epithelial structures. Here we provide an overview of the major molecular and cellular processes underlying the morphogenesis and patterning of the ureteric bud epithelium and its roles in the cortical-medullary patterning of the metanephric kidney. PMID:25783232

  5. The effect of Zn on the digestive gland epithelium of Porcellio scaber (Isopoda, Crustacea).

    PubMed

    Drobne, D; Strus, J

    1996-01-01

    The effect of zinc (Zn)-contaminated food on the shape of digestive gland epithelium was studied in the terrestrial isopod, Porcellio scaber. In animals fed with 5,000 micrograms Zn g-1 dry wt. of food, the epithelium was flattened in the anterior part of the gland tube. In the posterior part of the gland tube, the shape and size of cells did not change drastically, but they had folded apical surface. In animals fed with more Zn-contaminated food (10,000 micrograms Zn g-1 dry wt.) the epithelium was uniformly flattened and the basal lamina was intensively folded. In both cases, reduction of lipid bodies was evident. The possibility of using the shape of the gland epithelium as a biomarker of toxic chemicals is discussed.

  6. Quantitative analysis of squamous epithelium of normal palatal mucosa in guinea pigs.

    PubMed

    Andersen, L; Schroeder, H E

    1978-07-01

    The epithelium of intact guinea pig palate was subjected to stereologic analysis in a study of structural alterations in the keratinizing epithelium in response to wounding. Point counting procedures were employed to analyse electron micrographs sampled from three epithelial strata in biopsies collected from five animals. The differentiation pattern of the guinea pig palate epithelium displayed the following structural density gradients from basal to granular layers: descending gradients of metabolically active organelles, ascending gradient of bundled filaments coupled with the appearance of membrane coating granules and keratohyalin granules, and a plateau-like gradient of cytoplasmic ground substance. This pattern of epithelial differentiation is basically identical to that of human hard palate epithelium and epidermis. Regional and species variations in structure of keratinizing epithelia are suggested based on interepithelial differences in morphometric parameters.

  7. Mechanisms of neuronal chloride accumulation in intact mouse olfactory epithelium.

    PubMed

    Nickell, William T; Kleene, Nancy K; Kleene, Steven J

    2007-09-15

    When olfactory receptor neurons respond to odours, a depolarizing Cl(-) efflux is a substantial part of the response. This requires that the resting neuron accumulate Cl(-) against an electrochemical gradient. In isolated olfactory receptor neurons, the Na(+)-K(+)-2Cl(-) cotransporter NKCC1 is essential for Cl(-) accumulation. However, in intact epithelium, a robust electrical olfactory response persists in mice lacking NKCC1. This response is largely due to a neuronal Cl(-) efflux. It thus appears that NKCC1 is an important part of a more complex system of Cl(-) accumulation. To identify the remaining transport proteins, we first screened by RT-PCR for 21 Cl(-) transporters in mouse nasal tissue containing olfactory mucosa. For most of the Cl(-) transporters, the presence of mRNA was demonstrated. We also investigated the effects of pharmacological block or genetic ablation of Cl(-) transporters on the olfactory field potential, the electroolfactogram (EOG). Mice lacking the common Cl(-)/HCO(3)(-) exchanger AE2 had normal EOGs. Block of NKCC cotransport with bumetanide reduced the EOG in epithelia from wild-type mice but had no effect in mice lacking NKCC1. Hydrochlorothiazide, a blocker of the Na(+)-Cl(-) cotransporter, had only a small effect. DIDS, a blocker of some KCC cotransporters and Cl(-)/HCO(3)(-) exchangers, reduced the EOG in epithelia from both wild-type and NKCC1 knockout mice. A combination of bumetanide and DIDS decreased the response more than either drug alone. However, no combination of drugs completely abolished the Cl(-) component of the response. These results support the involvement of both NKCC1 and one or more DIDS-sensitive transporters in Cl(-) accumulation in olfactory receptor neurons.

  8. Mechanisms of neuronal chloride accumulation in intact mouse olfactory epithelium

    PubMed Central

    Nickell, William T; Kleene, Nancy K; Kleene, Steven J

    2007-01-01

    When olfactory receptor neurons respond to odours, a depolarizing Cl− efflux is a substantial part of the response. This requires that the resting neuron accumulate Cl− against an electrochemical gradient. In isolated olfactory receptor neurons, the Na+–K+–2Cl− cotransporter NKCC1 is essential for Cl− accumulation. However, in intact epithelium, a robust electrical olfactory response persists in mice lacking NKCC1. This response is largely due to a neuronal Cl− efflux. It thus appears that NKCC1 is an important part of a more complex system of Cl− accumulation. To identify the remaining transport proteins, we first screened by RT-PCR for 21 Cl− transporters in mouse nasal tissue containing olfactory mucosa. For most of the Cl− transporters, the presence of mRNA was demonstrated. We also investigated the effects of pharmacological block or genetic ablation of Cl− transporters on the olfactory field potential, the electroolfactogram (EOG). Mice lacking the common Cl−/HCO3− exchanger AE2 had normal EOGs. Block of NKCC cotransport with bumetanide reduced the EOG in epithelia from wild-type mice but had no effect in mice lacking NKCC1. Hydrochlorothiazide, a blocker of the Na+–Cl− cotransporter, had only a small effect. DIDS, a blocker of some KCC cotransporters and Cl−/HCO3− exchangers, reduced the EOG in epithelia from both wild-type and NKCC1 knockout mice. A combination of bumetanide and DIDS decreased the response more than either drug alone. However, no combination of drugs completely abolished the Cl− component of the response. These results support the involvement of both NKCC1 and one or more DIDS-sensitive transporters in Cl− accumulation in olfactory receptor neurons. PMID:17656441

  9. Surface elastic properties of human retinal pigment epithelium melanosomes.

    PubMed

    Guo, Senli; Hong, Lian; Akhremitchev, Boris B; Simon, John D

    2008-01-01

    Atomic force microscope (AFM) imaging and nanoindentation measurements in water were used to probe the mechanical properties of retinal pigment epithelium melanosomes isolated from 14-year-old and 76-year-old donors. Topographic imaging reveals surface roughness similar to previous measurements on dry melanosomes. Force-indentation measurements show different types of responses that were catalogued into four different categories. In these measurements no permanent surface damage of melanosomes was observed as revealed by imaging before and after indentation measurements. The indentation measurements that exhibited nearly elastic responses were used to determine the Young's modulus of melanosomes. The average Young's modulus values are similar for 14-year-old and 76-year-old melanosomes with a somewhat narrower distribution for the 14-year-old sample. These elastic modulus values are considerably higher than the modulus of organelles with cytoplasm (<1 MPa) and approaching values of the modulus of protein crystals (approximately 100 MPa) indicating rather high packing density of biologic material in melanosomes. The width of the Young's modulus distributions is considerable spanning from few megapascals to few tens of megapascals indicating large heterogeneity in the structure. A fraction of the force curves cannot be described by the homogeneous elastic sample model; these force curves are consistent with approximately 10 nm structural heterogeneity in melanosomes. The approach-withdraw hysteresis indicates a significant viscoelasticity, particularly in the samples from the 14-year-old sample. Adhesion of the AFM probe was detected on approximately 3% and approximately 20% of the surface of 14-year-old and 76-year-old samples, respectively. In light of previous studies on these same melanosomes using photoelectron emission microscopy, this adhesion is attributed to the presence of lipofuscin on the surface of the melanosomes. This suggestion indicates that part of

  10. Methoxychlor induces proliferation of the mouse ovarian surface epithelium.

    PubMed

    Symonds, Daniel A; Tomic, Dragana; Miller, Kimberly P; Flaws, Jodi A

    2005-02-01

    While the pesticide methoxychlor (MXC) has a variety of adverse effects on the female reproductive system, the effects of MXC on the ovarian surface epithelium (OSE) are unknown. Thus, this study tested the hypothesis that MXC alters the growth of the OSE. Mouse OSE cells were isolated by enzymatic digestion and cultured with vehicle, 3 microM of MXC, or 3 microM of 2,2-bis[p-hydroxyphenyl]-1,1,1,-trichloroethane (HPTE) for 14 days. After culture, proliferation and apoptosis were assessed by measurement of cell density, immunohistochemistry, and real-time polymerase chain reaction. Cell density was 66% greater for MXC-treated cells and 95% greater for HPTE-treated cells than controls (p < or = 0.05). The estrogen receptor blocker ICI 182,780 abolished MXC- and HPTE-induced increases in cell density. Proliferating cell nuclear antigen (PCNA) staining was positive in only 22 +/- 2.3% of controls, compared to 35 +/- 2.4% of MXC-treated cells and 40 +/- 2.4% of HPTE-treated cells (p < or = 0.05). The cell cycle regulators, cyclinD2 and cdk4, were significantly increased in MXC- and HPTE-treated cells compared to controls. The ApopTag assay demonstrated apoptotic cells in 4.8 +/- 0.45% of controls, 2.2 +/- 0.56% of MXC-treated cells, and 2.1 +/- 0.33% of HPTE-treated cells (p < or = 0.005). Expression of bcl-2 was significantly increased in MXC- and HPTE-treated cells, while bax was decreased in MXC- and HPTE-treated cells compared to controls. Collectively, these data indicate that MXC and HPTE stimulate OSE cell growth by increasing proliferation and inhibiting apoptosis. Further, since ICI 182,780 blocked MXC- and HPTE-induced OSE growth, these data suggest that the effects of MXC and HPTE on the OSE are mediated by estrogen receptors.

  11. Protective responses to sublytic complement in the retinal pigment epithelium.

    PubMed

    Tan, Li Xuan; Toops, Kimberly A; Lakkaraju, Aparna

    2016-08-01

    The retinal pigment epithelium (RPE) is a key site of injury in inherited and age-related macular degenerations. Abnormal activation of the complement system is a feature of these blinding diseases, yet how the RPE combats complement attack is poorly understood. The complement cascade terminates in the cell-surface assembly of membrane attack complexes (MACs), which promote inflammation by causing aberrant signal transduction. Here, we investigated mechanisms crucial for limiting MAC assembly and preserving cellular integrity in the RPE and asked how these are compromised in models of macular degeneration. Using polarized primary RPE and the pigmented Abca4(-/-) Stargardt disease mouse model, we provide evidence for two protective responses occurring within minutes of complement attack, which are essential for maintaining mitochondrial health in the RPE. First, accelerated recycling of the membrane-bound complement regulator CD59 to the RPE cell surface inhibits MAC formation. Second, fusion of lysosomes with the RPE plasma membrane immediately after complement attack limits sustained elevations in intracellular calcium and prevents mitochondrial injury. Cholesterol accumulation in the RPE, induced by vitamin A dimers or oxidized LDL, inhibits these defense mechanisms by activating acid sphingomyelinase (ASMase), which increases tubulin acetylation and derails organelle traffic. Defective CD59 recycling and lysosome exocytosis after complement attack lead to mitochondrial fragmentation and oxidative stress in the RPE. Drugs that stimulate cholesterol efflux or inhibit ASMase restore both these critical safeguards in the RPE and avert complement-induced mitochondrial injury in vitro and in Abca4(-/-) mice, indicating that they could be effective therapeutic approaches for macular degenerations. PMID:27432952

  12. Transcriptional Regionalization of the Fruit Fly’s Airway Epithelium

    PubMed Central

    Faisal, Muhammad N.; Hoffmann, Julia; El-Kholy, Samar; Kallsen, Kimberley; Wagner, Christina; Bruchhaus, Iris; Fink, Christine; Roeder, Thomas

    2014-01-01

    Although airway epithelia are primarily devoted to gas exchange, they have to fulfil a number of different tasks including organ maintenance and the epithelial immune response to fight airborne pathogens. These different tasks are at least partially accomplished by specialized cell types in the epithelium. In addition, a proximal to distal gradient mirroring the transition from airflow conduction to real gas exchange, is also operative. We analysed the airway system of larval Drosophila melanogaster with respect to region-specific expression in the proximal to distal axis. The larval airway system is made of epithelial cells only. We found differential expression between major trunks of the airways and more distal ones comprising primary, secondary and terminal ones. A more detailed analysis was performed using DNA-microarray analysis to identify cohorts of genes that are either predominantly expressed in the dorsal trunks or in the primary/secondary/terminal branches of the airways. Among these differentially expressed genes are especially those involved in signal transduction. Wnt-signalling associated genes for example are predominantly found in secondary/terminal airways. In addition, some G-protein coupled receptors are differentially expressed between both regions of the airways, exemplified by those activated by octopamine or tyramine, the invertebrate counterparts of epinephrine and norepinephrine. Whereas the OAMB is predominantly found in terminal airway regions, the oct3βR has higher expression levels in dorsal trunks. In addition, we observed a significant association of both, genes predominantly expressed in dorsal trunks or in primary to terminal branches branches with those regulated by hypoxia. Taken together, this observed differential expression is indicative for a proximal to distal transcriptional regionalization presumably reflecting functional differences in these parts of the fly’s airway system. PMID:25020150

  13. Injurious effects of lysophosphatidylcholine on barrier properties of alveolar epithelium.

    PubMed

    Niewoehner, D E; Rice, K; Sinha, A A; Wangensteen, D

    1987-11-01

    We studied the effects of lysophosphatidylcholine (lysoPC) on the barrier properties and the morphology of the alveolar-capillary membrane in isolated, fluid-filled hamster lungs continuously perfused. When instilled into the airspace at initial concentrations of 8-128 micrograms/ml, lysoPC causes dose-dependent increases in the permeability-surface area product of the alveolar epithelium for small (14C-sucrose, 342) and large (125I-neutral dextran, 70,000) solutes, with maximal values for each solute approximately 15 times control. Rapid whole-lung weight gains are caused by 128 micrograms lysoPC per milliliter, but each of the lower concentrations has no effect on net lung water balance. Electron-microscopic studies demonstrate that type I pneumonocytes are the lung cells most susceptible to lysoPC exposure, with cell swelling being the most prominent feature from low-dose exposure with more severe disruptive changes at the highest concentration tested. The effects of lysoPC are relatively specific, as several structurally related lipids have little or no effect at equivalent concentrations. Instillation of phospholipase A2 causes functional changes similar to those seen with lysoPC, presumably by generation of lysoPC from endogenous phospholipids. Studies employing a 14C-radiolabeled compound show that instilled lysoPC rapidly partitions into the lung lipid fraction where a major portion of the acyl group becomes incorporated into phosphatidylcholine. The amount of instilled lysoPC required to produce functional and morphological effects comprises only a few percent of total lung phospholipids. Since lysoPC is a normal component of lung phospholipids, severe lung dysfunction might result from minor abnormalities in the formation or degradation of this compound.

  14. Accelerated Shedding of Prions following Damage to the Olfactory Epithelium

    PubMed Central

    Wilham, Jason M.; Lowe, Diana; Watschke, Christopher P.; Shearin, Harold; Martinka, Scott; Caughey, Byron; Wiley, James A.

    2012-01-01

    In this study, we investigated the role of damage to the nasal mucosa in the shedding of prions into nasal samples as a pathway for prion transmission. Here, we demonstrate that prions can replicate to high levels in the olfactory sensory epithelium (OSE) in hamsters and that induction of apoptosis in olfactory receptor neurons (ORNs) in the OSE resulted in sloughing off of the OSE from nasal turbinates into the lumen of the nasal airway. In the absence of nasotoxic treatment, olfactory marker protein (OMP), which is specific for ORNs, was not detected in nasal lavage samples. However, after nasotoxic treatment that leads to apoptosis of ORNs, both OMP and prion proteins were present in nasal lavage samples. The cellular debris that was released from the OSE into the lumen of the nasal airway was positive for both OMP and the disease-specific isoform of the prion protein, PrPSc. By using the real-time quaking-induced conversion assay to quantify prions, a 100- to 1,000-fold increase in prion seeding activity was observed in nasal lavage samples following nasotoxic treatment. Since neurons replicate prions to higher levels than other cell types and ORNs are the most environmentally exposed neurons, we propose that an increase in ORN apoptosis or damage to the nasal mucosa in a host with a preexisting prion infection of the OSE could lead to a substantial increase in the release of prion infectivity into nasal samples. This mechanism of prion shedding from the olfactory mucosa could contribute to prion transmission. PMID:22130543

  15. Optical modulation of transgene expression in retinal pigment epithelium

    NASA Astrophysics Data System (ADS)

    Palanker, D.; Lavinsky, D.; Chalberg, T.; Mandel, Y.; Huie, P.; Dalal, R.; Marmor, M.

    2013-03-01

    Over a million people in US alone are visually impaired due to the neovascular form of age-related macular degeneration (AMD). The current treatment is monthly intravitreal injections of a protein which inhibits Vascular Endothelial Growth Factor, thereby slowing progression of the disease. The immense financial and logistical burden of millions of intravitreal injections signifies an urgent need to develop more long-lasting and cost-effective treatments for this and other retinal diseases. Viral transfection of ocular cells allows creation of a "biofactory" that secretes therapeutic proteins. This technique has been proven successful in non-human primates, and is now being evaluated in clinical trials for wet AMD. However, there is a critical need to down-regulate gene expression in the case of total resolution of retinal condition, or if patient has adverse reaction to the trans-gene products. The site for genetic therapy of AMD and many other retinal diseases is the retinal pigment epithelium (RPE). We developed and tested in pigmented rabbits, an optical method to down-regulate transgene expression in RPE following vector delivery, without retinal damage. Microsecond exposures produced by a rapidly scanning laser vaporize melanosomes and destroy a predetermined fraction of the RPE cells selectively. RPE continuity is restored within days by migration and proliferation of adjacent RPE, but since the transgene is not integrated into the nucleus it is not replicated. Thus, the decrease in transgene expression can be precisely determined by the laser pattern density and further reduced by repeated treatment without affecting retinal structure and function.

  16. Human milk hyaluronan enhances innate defense of the intestinal epithelium.

    PubMed

    Hill, David R; Rho, Hyunjin K; Kessler, Sean P; Amin, Ripal; Homer, Craig R; McDonald, Christine; Cowman, Mary K; de la Motte, Carol A

    2013-10-01

    Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn.

  17. Transcriptome analysis and molecular signature of human retinal pigment epithelium

    PubMed Central

    Strunnikova, N.V.; Maminishkis, A.; Barb, J.J.; Wang, F.; Zhi, C.; Sergeev, Y.; Chen, W.; Edwards, A.O.; Stambolian, D.; Abecasis, G.; Swaroop, A.; Munson, P.J.; Miller, S.S.

    2010-01-01

    Retinal pigment epithelium (RPE) is a polarized cell layer critical for photoreceptor function and survival. The unique physiology and relationship to the photoreceptors make the RPE a critical determinant of human vision. Therefore, we performed a global expression profiling of native and cultured human fetal and adult RPE and determined a set of highly expressed ‘signature’ genes by comparing the observed RPE gene profiles to the Novartis expression database (SymAtlas: http://wombat.gnf.org/index.html) of 78 tissues. Using stringent selection criteria of at least 10-fold higher expression in three distinct preparations, we identified 154 RPE signature genes, which were validated by qRT-PCR analysis in RPE and in an independent set of 11 tissues. Several of the highly expressed signature genes encode proteins involved in visual cycle, melanogenesis and cell adhesion and Gene ontology analysis enabled the assignment of RPE signature genes to epithelial channels and transporters (ClCN4, BEST1, SLCA20) or matrix remodeling (TIMP3, COL8A2). Fifteen RPE signature genes were associated with known ophthalmic diseases, and 25 others were mapped to regions of disease loci. An evaluation of the RPE signature genes in a recently completed AMD genomewide association (GWA) data set revealed that TIMP3, GRAMD3, PITPNA and CHRNA3 signature genes may have potential roles in AMD pathogenesis and deserve further examination. We propose that RPE signature genes are excellent candidates for retinal diseases and for physiological investigations (e.g. dopachrome tautomerase in melanogenesis). The RPE signature gene set should allow the validation of RPE-like cells derived from human embryonic or induced pluripotent stem cells for cell-based therapies of degenerative retinal diseases. PMID:20360305

  18. Mesenchymal signaling in dorsoventral differentiation of palatal epithelium.

    PubMed

    Sohn, Wern-Joo; Gwon, Gi-Jeong; Kim, Hyeng-Soo; Neupane, Sanjiv; Cho, Sung-Jin; Lee, Jae-Hyung; Yamamoto, Hitoshi; Choi, Je-Yong; An, Chang-Hyeon; Lee, Youngkyun; Shin, Hong-In; Lee, Sanggyu; Kim, Jae-Young

    2015-12-01

    After palatal fusion, the dorsal and ventral epithelia of the palatal shelf differentiate into the nasal and oral mucosa, respectively. The tissue-specific differentiation of palatal epithelia along the dorsal-ventral axis is regulated by the signaling molecules expressed in the underlying mesenchyme. Thus, as in many other epithelial organs, differentiation relies on epithelial-mesenchymal interactions. To screen for region-specific mesenchymal signaling molecules that determine the fate of the palatal epithelia, we employed a laser microdissection (LMD) method. LMD allowed us to collect region-specific mesenchymal tissues at E13, prior to palatal fusion and the development of distinct dorsal and ventral epithelial morphology. Genome-wide screening was performed on the tissues collected using LMD to identify candidate mesenchymal signaling molecules. The microarray results were validated using real-time quantitative (qPCR) and in situ hybridization methods. The developmental role and interactions of the candidate genes were evaluated in in vitro-cultivated E13 palates using an anti-sense oligodeoxynucleotide (AS-ODN)-based loss-of-function approach. Apparent changes in the expression patterns of Runt-related transcription factor 2 (Runx2) and LIM homeobox 8 (Lhx8) were observed after knocking down each gene. Knock-down of Runx2 and Lhx8 also altered the immunolocalization pattern of cytokeratin18 (CK18), an established marker for nasal epithelium. These results were confirmed using Runx2 heterozygote mice. The mesenchymal signaling molecules Runx2 and Lhx8, which possess region-specific expression patterns along the dorsoventral axis, functionally interact to regulate the cellular and molecular characteristics of dorsal and ventral epithelia, suggesting that mesenchymal signaling molecules determine the dorsoventral fate of epithelial structures in the developing palate. PMID:26123167

  19. Acid secretion and proton conductance in human airway epithelium.

    PubMed

    Fischer, Horst; Widdicombe, Jonathan H; Illek, Beate

    2002-04-01

    Acid secretion and proton conductive pathways across primary human airway surface epithelial cultures were investigated with the pH stat method in Ussing chambers and by single cell patch clamping. Cultures showed a basal proton secretion of 0.17 +/- 0.04 micromol.h(-1).cm(-2), and mucosal pH equilibrated at 6.85 +/- 0.26. Addition of histamine or ATP to the mucosal medium increased proton secretion by 0.27 +/- 0.09 and 0.24 +/- 0.09 micromol.h(-1).cm(-2), respectively. Addition of mast cells to the mucosal medium of airway cultures similarly activated proton secretion. Stimulated proton secretion was similar in cultures bathed mucosally with either NaCl Ringer or ion-free mannitol solutions. Proton secretion was potently blocked by mucosal ZnCl(2) and was unaffected by mucosal bafilomycin A(1), Sch-28080, or ouabain. Mucosal amiloride blocked proton secretion in tissues that showed large amiloride-sensitive potentials. Proton secretion was sensitive to the application of transepithelial current and showed outward rectification. In whole cell patch-clamp recordings a strongly outward-rectifying, zinc-sensitive, depolarization-activated proton conductance was identified with an average chord conductance of 9.2 +/- 3.8 pS/pF (at 0 mV and a pH 5.3-to-pH 7.3 gradient). We suggest that inflammatory processes activate proton secretion by the airway epithelium and acidify the airway surface liquid.

  20. Lingual cyst lined by respiratory epithelium: a case report and review of literature.

    PubMed

    Juneja, Manish; Boaz, Karen; Srikant, N; Nandita, K P; Vidya, M

    2011-01-01

    The present report describes a case of a lingual cyst lined by a respiratory epithelium occurring in a 1-year-old girl. The article also reviews the cases published in the literature under the heading of lingual cysts and segregates all the cases having predominant respiratory epithelium as the cystic lining. Reclassification, with more descriptive histologic terminology to name the lingual cysts, has been proposed.

  1. Macrophages are required for dendritic cell uptake of respiratory syncytial virus from an infected epithelium.

    PubMed

    Ugonna, Kelechi; Bingle, Colin D; Plant, Karen; Wilson, Kirsty; Everard, Mark L

    2014-01-01

    We have previously shown that the respiratory syncytial virus [RSV] can productively infect monocyte derived dendritic cells [MoDC] and remain dormant within the same cells for prolonged periods. It is therefore possible that infected dendritic cells act as a reservoir within the airways of individuals between annual epidemics. In the present study we explored the possibility that sub-epithelial DCs can be infected with RSV from differentiated bronchial epithelium and that in turn RSV from DCs can infect the epithelium. A dual co-culture model was established in which a differentiated primary airway epithelium on an Air Liquid Interface (ALI) was cultured on a transwell insert and MoDCs were subsequently added to the basolateral membrane of the insert. Further experiments were undertaken using a triple co-culture model in which in which macrophages were added to the apical surface of the differentiated epithelium. A modified RSV [rr-RSV] expressing a red fluorescent protein marker of replication was used to infect either the MoDCs or the differentiated epithelium and infection of the reciprocal cell type was assessed using confocal microscopy. Our data shows that primary epithelium became infected when rr-RSV infected MoDCs were introduced onto the basal surface of the transwell insert. MoDCs located beneath the epithelium did not become infected with virus from infected epithelial cells in the dual co-culture model. However when macrophages were present on the apical surface of the primary epithelium infection of the basal MoDCs occurred. Our data suggests that RSV infected dendritic cells readily transmit infection to epithelial cells even when they are located beneath the basal layer. However macrophages appear to be necessary for the transmission of infection from epithelial cells to basal dendritic cells.

  2. The specialised structure of crypt epithelium in the human palatine tonsil and its functional significance.

    PubMed

    Perry, M E

    1994-08-01

    Material from 25 human palatine tonsils was studied by light microscopy, immunocytochemistry, scanning and transmission electron microscopy. Special attention was focused on the structure of the epithelium lining the tonsillar crypts in the context of its ascribed immunological functions. This epithelium was not uniform and contained patches of stratified squamous nonkeratinising epithelium and patches of reticulated sponge-like epithelium. The degree of reticulation of the epithelial cells and the infiltration of nonepithelial cells varied. Reticulated patches were associated with disruptions in the continuity of basement membrane, and often also with desquamation of the upper cell layers, and contained numerous small blood vessels. The epithelial cells showed considerable variation in their morphology when surrounded by infiltrating cells. The rearrangement of their cytoskeleton and redistribution of desmosomal contacts indicate the responsiveness and dynamic nature of such epithelium. Cytoplasmic glycogen granules, located in the upper strata, suggest the possibility of energy-demanding functions such as absorption and secretion. The numerous membrane-coating granules may have contributed to cell membrane thickening and possibly also to tonsillar mucosal protection. Some areas contained a few keratohyalin granules but there was little evidence of keratinisation. The presence, and sometimes the predominance, of nonepithelial cells was characteristic of the reticulated epithelium. T and B cells often infiltrated the whole epithelial thickness, and many plasma cells were located around intraepithelial vessels, while macrophages and interdigitating cells showed a patchy distribution. It is proposed that the major functions of the reticulated epithelium are: (1) to provide a favourable environment for the intimate contact between the effector cells of immune responses; (2) to facilitate direct transport of antigens; (3) to synthesise the secretory component

  3. Cultivated Oral Mucosa Epithelium in Ocular Surface Reconstruction in Aniridia Patients

    PubMed Central

    Dobrowolski, Dariusz; Orzechowska-Wylegala, Boguslawa; Wowra, Bogumil; Wroblewska-Czajka, Ewa; Grolik, Maria; Szczubialka, Krzysztof; Nowakowska, Maria; Puzzolo, Domenico; Wylegala, Edward A.; Micali, Antonio; Aragona, Pasquale

    2015-01-01

    Purpose. Efficacy of cultivated oral mucosa epithelial transplantation (COMET) procedure in corneal epithelium restoration of aniridia patients. Methods. Study subjects were aniridia patients (13 patients; 17 eyes) with irregular, vascular conjunctival pannus involving visual axis who underwent autologous transplantation of cultivated epithelium. For the procedure oral mucosa epithelial cells were obtained from buccal mucosa with further enzymatic treatment. Suspension of single cells was seeded on previously prepared denuded amniotic membrane. Cultures were carried on culture dishes inserts in the presence of the inactivated with Mitomycin C monolayer of 3T3 fibroblasts. Cultures were carried for seven days. Stratified oral mucosa epithelium with its amniotic membrane carrier was transplanted on the surgically denuded corneal surface of aniridia patients with total or subtotal limbal stem cell deficiency. Outcome Measures. Corneal surface, epithelial regularity, and visual acuity improvement were evaluated. Results. At the end of the observation period, 76.4% of the eyes had regular transparent epithelium and 23.5% had developed epithelial defects or central corneal haze; in 88.2% of cases visual acuity had increased. VA range was from HM 0.05 before the surgery to HM up to 0.1 after surgery. Conclusion. Application of cultivated oral mucosa epithelium restores regular epithelium on the corneal surface with moderate improvement in quality of vision. PMID:26451366

  4. Stages and duration of the cycle of the seminiferous epithelium in oncilla (Leopardus tigrinus, Schreber, 1775).

    PubMed

    Balarini, Maytê Koch; de Paula, Tarcízio Antônio Rego; da Matta, S L Pinto; Peixoto, J Vogas; Guião-Leite, F Lima; Rossi Júnior, J L; Czermak Junior, A C; Walker, N J

    2012-03-15

    Six adult Leopardus tigrinus (oncilla) were studied to characterize stages of the seminiferous epithelium cycle and its relative frequency and duration, as well as morphometric parameters of the testes. Testicular fragments were obtained (incisional biopsy), embedded (glycol methacrylate), and histologic sections examined with light microscopy. The cycle of the seminiferous epithelium was categorized into eight stages (based on the tubular morphology method). The duration of one seminiferous epithelium cycle was 9.19 d, and approximately 41.37 d were required for development of sperm from spermatogonia. On average, diameter of the seminiferous tubules was 228.29 μm, epithelium height was 78.86 μm, and there were 16.99 m of testicular tubules per gram of testis. Body weight averaged 2.589 kg, of which 0.06 and 0.04% were attributed to the testis and seminiferous tubules, respectively. In conclusion, there were eight distinct stages in the seminiferous epithelium, the length of the seminiferous epithelium cycle was close to that in domestic cats and cougars, and testicular and somatic indexes were similar to those of other carnivores of similar size.

  5. [Lamellar Inclusion Bodies in the Retinal Pigment Epithelium of Diurnal Rodents].

    PubMed

    Samosudova, N V; Orlov, O U; Golyshev, S A

    2015-01-01

    The ultrastructure of the retinal pigment epithelium of a diurnal rodent (Brandt's vole) was described taking into account 1) the functions of the pigment epithelium as a participant in the renewal of photoreceptor outer segment and. 2) digestion of outer segment membranes into phagosomes of the retinal pigment epithelium. The myeloid bodies were observed after exposure of the pigment epithelium to light (200 lux, 4 hours) and darkness (0,1 lux, 1,5-hour). In the cytoplasm of the pigment epithelium of the vole no myeloid bodies were observed. Instead of it small lamellar bodies, which have the spiral form and size (from - 200 to 400 nm) were found. The structure of these lamellar bodies was described. Furthermore, the structures, which were presumably responsible for the transport of the digested material, were revealed. The evidence of it is the presence of 1) dense precipitate in the apical domain of the pigment epithelium and 2) microtubules which participate in transport of this precipitate. PMID:26591606

  6. Squamous Metaplasia Is Increased in the Bronchial Epithelium of Smokers with Chronic Obstructive Pulmonary Disease

    PubMed Central

    Rigden, Helen M.; Alias, Ahmad; Havelock, Thomas; O'Donnell, Rory; Djukanovic, Ratko; Davies, Donna E.; Wilson, Susan J.

    2016-01-01

    Aims To quantify the extent of squamous metaplasia in bronchial biopsies and relate it to the presence of chronic obstructive pulmonary disease (COPD), a smoking-related pathology. Methods Bronchial biopsies (n = 15 in each group) from smokers with COPD GOLD stage1 and GOLD stage2, smokers without COPD and healthy non-smokers were stained immunohistochemically with a panel of antibodies that facilitated the identification of pseudostratified epithelium and distinction of squamous metaplasia and squamous epithelium from tangentially cut epithelium. The percentage length of each of these epithelial phenotypes was measured as a percent of total epithelial length using computerised image analysis. Sections were also stained for carcinoembryonic antigen and p53, early markers of carcinogenesis, and Ki67, and the percentage epithelial expression measured. Results The extent of squamous metaplasia was significantly increased in both COPD1 and COPD2 compared to healthy smokers and healthy non-smokers. The amount of fully differentiated squamous epithelium was also increased in COPD1 and COPD2 compared to healthy non-smokers, as was the expression of carcinoembryonic antigen. These features correlated with one other. Conclusion In subjects with COPD there is a loss of pseudostratified epithelium accompanied by an increase in squamous metaplasia with transition into a fully squamous epithelium and expression of early markers of carcinogenesis. PMID:27228128

  7. [Lamellar Inclusion Bodies in the Retinal Pigment Epithelium of Diurnal Rodents].

    PubMed

    Samosudova, N V; Orlov, O U; Golyshev, S A

    2015-01-01

    The ultrastructure of the retinal pigment epithelium of a diurnal rodent (Brandt's vole) was described taking into account 1) the functions of the pigment epithelium as a participant in the renewal of photoreceptor outer segment and. 2) digestion of outer segment membranes into phagosomes of the retinal pigment epithelium. The myeloid bodies were observed after exposure of the pigment epithelium to light (200 lux, 4 hours) and darkness (0,1 lux, 1,5-hour). In the cytoplasm of the pigment epithelium of the vole no myeloid bodies were observed. Instead of it small lamellar bodies, which have the spiral form and size (from - 200 to 400 nm) were found. The structure of these lamellar bodies was described. Furthermore, the structures, which were presumably responsible for the transport of the digested material, were revealed. The evidence of it is the presence of 1) dense precipitate in the apical domain of the pigment epithelium and 2) microtubules which participate in transport of this precipitate.

  8. Biblical behavior modification.

    PubMed

    Lasure, L C; Mikulas, W L

    1996-07-01

    Although we may have formalized and systematized the field of behavior modification in the last few decades, people around the world have been using behavioral change strategies throughout history. Premack's (1965) theory of reinforcement is often called "Grandma's rule" because grandmothers have long been using it (e.g. You must finish your vegetables before you may go out and play). Franks (1969, p. 4), in one of the first behavioral texts, gave historical examples from China, Turkey, France, and Italy. Knapp and Shodahl (1974) showed how Benjamin Franklin used behavior modification. And de Silva (1984, 1985) gave examples of behavior modification by the Buddha and other early Buddhists. Conspicuously absent from our literature are examples from the Judeo-Christian tradition. In this paper, we provide a number of behavior modification examples from the Bible (New International Version). Footnotes provide references for many more examples. In the discussion, we explore implications for education and therapy. Examples are grouped by the following categories: operant conditioning, respondent conditioning, modeling, and cognitive interventions. However, the Biblical examples, like contemporary case studies, do not always fall neatly into discrete categories. They often are a combination, particularly operant and respondent conditioning interweaving.

  9. Diet Modification for Hyperlipidemia

    PubMed Central

    Mann, Heather D.; Piotrowski, Pamela

    1992-01-01

    Hyperlipidemia is a major risk factor associated with cardiovascular disease. Dietary modification is effective in achieving and maintaining improved serum lipid levels. Nutritional care provided by a dietitian includes individual dietary and lifestyle assessment, formulating an appropriate dietary regimen, education, and follow-up assessments. PMID:21221406

  10. Behavior Modification with Children

    ERIC Educational Resources Information Center

    Brown, Daniel G.

    1972-01-01

    The author urges wider use of positive reinforcement theories in helping emotionally disturbed and mentally handicapped children. Underlining the influence of environment on behavior, he also notes that behavior modification programs utilize fewer trained personnel more effectively and, like Tennessee's Re-Education Treatment, allow for therapy in…

  11. Behavior Modification for Teachers.

    ERIC Educational Resources Information Center

    Maryland Univ., College Park. Coll. of Education.

    The Active Student Participation Program (ASPP), developed by the Department of Counseling and Personnel Services in the University of Maryland College of Education, was designed to disseminate knowledge of behavior modification principles. The course has been taught since the fall of 1971, and approximately 81 in-service teachers have completed…

  12. Toy Modification Note. Revised.

    ERIC Educational Resources Information Center

    Vanderheiden, Gregg C.; And Others

    Described are toy modifications which enable handicapped individuals to operate battery-powered toys. A battery interrupter is explained as a device which fits between the batteries in a toy and provides the ability to have a separate on-off switch which can be custom designed to fit a handicapped user's needs. Construction and use of three types…

  13. THE MODIFICATION OF STUTTERING.

    ERIC Educational Resources Information Center

    BRUTTEN, EUGENE J.; SHOEMAKER, DONALD J.

    INTENDED FOR BOTH THE COLLEGE STUDENT AND THE PROFESSIONAL SPEECH PATHOLOGIST, THE BOOK PRESENTS CURRENT LEARNING THEORIES CONCERNING STUTTERING, DATA IMPORTANT TO THE THEORIES, AND A 2-PROCESS THEORY OF LEARNING FOR THEORETICAL INTEGRATION OF THE DATA ON STUTTERING AND FOR THERAPEUTIC MODIFICATION. INFORMATION PRESENTED ABOUT BEHAVIORISTIC…

  14. THE CELL JUNCTION IN A LAMELLIBRANCH GILL CILIATED EPITHELIUM

    PubMed Central

    Satir, P.; Gilula, N. B.

    1970-01-01

    The junctional complex in the gill epithelium of the freshwater mussel (Elliptio complanatus) consists of an intermediary junction followed by a 2–3 µ long septate junction. Homologous and heterologous cell pairs are connected by this junction. After fixation with 1% OsO4 containing 1% potassium pyroantimonate, electron microscopy of the gill reveals deposits of electron-opaque precipitate, specifically and consistently localized along cellular membranes. In both junctional and nonjunctional membrane regions, the precipitate usefully outlines the convolutions without obliterating the 150 A intercellular space, which suggests the rarity or absence of either vertebrate-type gap or tight junctions along the entire cell border. The precipitate appears on the cytoplasmic side of the limiting unit membranes of frontal (F), laterofrontal (LF), intermediate (I), lateral (L), and postlateral (PL) cells. The membrane surfaces of certain vesicles of the smooth endoplasmic reticulum, of multivesicular bodies, and of mitochondrial cristae contain precipitate, as does the nucleolus. In other portions of the cell, precipitate is largely absent. The amount of over-all deposition is variable and depends on the treatment of the tissue prior to fixation. Deposition is usually enhanced by pretreatment with 40 mM NaCl as opposed to 40 mM KCl, which suggests that the precipitate is in part sodium pyroantimonate. Treatment with 0.2 mM ouabain does not enhance deposition. Regional differentiation of cell membranes with respect to their ability to precipitate pyroantimonate is found in at least three instances: (a) between the ciliary membranes and other portions of the cell membrane: the precipitate terminates abruptly at the ciliary base, (b) between the LF and I cell borders: the precipitate is asymmetric, favoring the LF side of the junction, and (c) between the septate junctional membrane and adjacent membrane: the precipitate occurs periodically throughout the septate junction

  15. Tracheal epithelium cell volume responses to hyperosmolar, isosmolar and hypoosmolar solutions: relation to epithelium-derived relaxing factor (EpDRF) effects

    PubMed Central

    Fedan, Jeffrey S.; Thompson, Janet A.; Ismailoglu, U. Burcin; Jing, Yi

    2013-01-01

    In asthmatic patients, inhalation of hyperosmolar saline or D-mannitol (D-M) elicits bronchoconstriction, but in healthy subjects exercise causes bronchodilation. Hyperventilation causes drying of airway surface liquid (ASL) and increases its osmolarity. Hyperosmolar challenge of airway epithelium releases epithelium-derived relaxing factor (EpDRF), which relaxes the airway smooth muscle. This pathway could be involved in exercise-induced bronchodilation. Little is known of ASL hyperosmolarity effects on epithelial function. We investigated the effects of osmolar challenge maneuvers on dispersed and adherent guinea-pig tracheal epithelial cells to examine the hypothesis that EpDRF-mediated relaxation is associated with epithelial cell shrinkage. Enzymatically-dispersed cells shrank when challenged with ≥10 mOsM added D-M, urea or NaCl with a concentration-dependence that mimics relaxation of the of isolated perfused tracheas (IPT). Cells shrank when incubated in isosmolar N-methyl-D-glucamine (NMDG) chloride, Na gluconate (Glu), NMDG-Glu, K-Glu and K2SO4, and swelled in isosmolar KBr and KCl. However, isosmolar challenge is not a strong stimulus of relaxation in IPTs. In previous studies amiloride and 4,4′-diisothiocyano-2,2′-stilbenedisulfonic acid (DIDS) inhibited relaxation of IPT to hyperosmolar challenge, but had little effect on shrinkage of dispersed cells. Confocal microscopy in tracheal segments showed that adherent epithelium is refractory to low hyperosmolar concentrations that induce dispersed cell shrinkage and relaxation of IPT. Except for gadolinium and erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA), actin and microtubule inhibitors and membrane permeabilizing agents did not affect on ion transport by adherent epithelium or shrinkage responses of dispersed cells. Our studies dissociate relaxation of IPT from cell shrinkage after hyperosmolar challenge of airway epithelium. PMID:24130533

  16. Pectin modifications: a review.

    PubMed

    Chen, Jun; Liu, Wei; Liu, Cheng-Mei; Li, Ti; Liang, Rui-Hong; Luo, Shun-Jing

    2015-01-01

    In recent years, the interest in studying modification of pectin has increased. A number of hydroxyl and carboxyl groups distributed along the backbone as well as a certain amount of neutral sugars presented as side chains make pectin capable of preparing a broad spectrum of derivatives. By forming pectin derivatives, their properties may be modified and some other new functional properties may be created. This article attempts to review the information about various methods used for pectin modification, including substitution (alkylation, amidation, quaternization, thiolation, sulfation, oxidation, etc.), chain elongation (cross-linking and grafting) and depolymerization (chemical, physical, and enzymatic degradation). Characteristics and applications of some pectin derivatives are also presented. In addition, the safety and regulatory status of pectin and its derivatives were reviewed.

  17. Muscarinic cholinergic and alpha 2-adrenergic receptors in the epithelium and muscularis of the human ileum

    SciTech Connect

    Lepor, H.; Rigaud, G.; Shapiro, E.; Baumann, M.; Kodner, I.J.; Fleshman, J.W. )

    1990-04-01

    The aim of this study was to characterize the binding and functional properties of muscarinic cholinergic (MCh) and alpha 2-adrenergic receptors in the human ileum to provide insight into pharmacologic strategies for managing urinary and fecal incontinence after bladder and rectal replacement with intestinal segments. MCh and alpha 2-adrenergic binding sites were characterized in the epithelium and muscularis of eight human ileal segments with 3H-N-methylscopolamine and 3H-rauwolscine, respectively. The dissociation constant for 3H-N-methylscopolamine in the epithelium and muscularis was 0.32 +/- 0.07 nmol/L and 0.45 +/- 0.10 nmol/L, respectively (p = 0.32). The MCh receptor content was approximately eightfold greater in the muscularis compared with the epithelium (p = 0.008). The dissociation constant for 3H-rauwolscine in the muscularis and epithelium was 2.55 +/- 0.42 nmol/L and 2.03 +/- 0.19 nmol/L, respectively (p = 0.29). The alpha 2-adrenoceptor density was twofold greater in the epithelium compared with the muscularis (p = 0.05). Noncumulative concentration-response experiments were performed with carbachol, an MCh agonist, and UK-14304, a selective alpha 2-adrenergic agonist. The epithelium did not contract in the presence of high concentrations of carbachol and UK-14304. The muscularis preparations were responsive only to carbachol. The muscularis contains primarily MCh receptors mediating smooth muscle contraction. The alpha 2-adrenoceptors are localized primarily to the epithelium and may regulate water secretion in the intestine. The distribution and functional properties of ileal MCh and alpha 2-adrenergic receptors provide a theoretic basis for the treatment of incontinence after bladder and rectal replacement with intestinal segments.

  18. Dimethylarsinic acid in drinking water changed the morphology of urinary bladder but not the expression of DNA repair genes of bladder transitional epithelium in F344 rats.

    PubMed

    Wang, Amy; Wolf, Douglas C; Sen, Banalata; Knapp, Geremy W; Holladay, Steven D; Huckle, William R; Caceci, Thomas; Robertson, John L

    2009-06-01

    Inorganic arsenic increases urinary bladder transitional cell carcinoma in humans. In F344 rats, dimethylarsinic acid (DMA[V]) increases transitional cell carcinoma. Arsenic-induced inhibition of DNA repair has been reported in cultured cell lines and in lymphocytes of arsenic-exposed humans, but it has not been studied in urinary bladder. Should inhibition of DNA damage repair in transitional epithelium occur, it may contribute to carcinogenesis or cocarcinogenesis. We investigated morphology and expression of DNA repair genes in F344 rat transitional cells following up to 100 ppm DMA(V) in drinking water for four weeks. Mitochondria were very sensitive to DMA(V), and swollen mitochondria appeared to be the main source of vacuoles in the transitional epithelium. Real-time reverse transcriptase polymerase chain reaction (Real-Time RT PCR) showed the mRNA levels of tested DNA repair genes, ataxia telangectasia mutant (ATM), X-ray repair cross-complementing group 1 (XRCC1), excision repair cross-complementing group 3/xeroderma pigmentosum B (ERCC3/XPB), and DNA polymerase beta (Polbeta), were not altered by DMA(V). These data suggested that either DMA(V) does not affect DNA repair in the bladder or DMA(V) affects DNA repair without affecting baseline mRNA levels of repair genes. The possibility remains that DMA(V) may lower damage-induced increases in repair gene expression or cause post-translational modification of repair enzymes.

  19. Expression of the carcinoma markers: the sialylated Lewis A and X carbohydrate antigens in normal laryngeal surface epithelium and submucosal glands from old humans.

    PubMed

    Kirkeby, Svend; Moe, Dennis

    2013-03-01

    Aberrant surface expression of the carbohydrate ABH and Lewis antigens are often used as markers for the diagnosis of cancer, but while the distribution of these histo-blood group antigens is relatively well-described in tissues and organs from young and middle-aged humans little is known of their expression in old age. The objective for this study was to estimate if the Lewis A and X antigens together with their sialylated modifications, are expressed in sections of normal laryngeal tissue from old humans. Antibodies directed against the tumor markers Sialyl Lewis A and Sialyl Lewis X showed positive reaction in the surface epithelia from normal larynx autopsies obtained from people aged 77-90 years. The sialylated and non-sialylated Lewis A antigens were more frequently expressed in the pseudostratified epithelium than in squamous surface epithelium. Both the sialylated and the non-sialylated carbohydrates were stained in the submucosal glands in all the autopsies. In conclusion, visualization of Lewis tumor markers in the larynx should be interpreted with great care, as they may be present in normal laryngeal epithelial cells from old humans.

  20. Barrett's esophageal cancer in which magnifying narrow-band imaging was useful for diagnosing extension under the squamous epithelium.

    PubMed

    Koike, Tomoyuki; Endo, Hiroyuki; Nakagawa, Kenichiro; Iijima, Katsunori; Shimosegawa, Tooru

    2013-05-01

    A 36-year-old man complained of heartburn. Gastrointestinal endoscopies showed a reddish and slightly depressed lesion in the right-anterior wall of the esophagogastric junction. With white light imaging, the area of the adenocarcinoma under the squamous epithelium was difficult to detect, but a slightly flat, elevated lesion appeared in the area of adenocarcinoma under the squamous epithelium. With narrow-band imaging (NBI) in the area of the Barrett's esophageal cancer under the squamous epithelium, a slight, brownish change could be observed. In addition, with the magnifying technique, irregular mesh-like vessels were observed, suggesting the presence of differentiated adenocarcinoma under the squamous epithelium. The lesion was resected en bloc by endoscopic submucosal dissection, and Barrett's esophageal cancer under the squamous epithelium was histologically confirmed. In this case, NBI with magnifying endoscopy was very useful to diagnose the extension of Barrett's esophageal cancer under the squamous epithelium.

  1. [Epithelium and anal glands in rectal pouches and fistula. Histologic studies of swine with congenital anal atresia].

    PubMed

    Lambrecht, W; Kluth, D; Lierse, W

    1989-02-01

    The epithelial coating of the rectal pouch and fistula was studied morphologically in 33 newborn piglets with high and low forms of anal atresia and was found to be similar to the epithelial coating of the anal canal in normal piglets: the typical epithelium of the rectum changed its character into transitional epithelium at the region of the internal sphincter which surrounded the fistulae in all animals. In the caudal part of the fistula the transitional epithelium was followed by squamous epithelium. Only in male piglets with deformities and recto-urethral fistulae no squamous epithelium was found. In these cases transitional epithelium covered all parts of the fistula and the region of the internal sphincter. Anal glands were found in all animals, with or without anorectal malformations. They always invaded the internal sphincter. According to our morphological studies the fistula in anorectal malformations represents an ectopic anal canal.

  2. Insulin Restores an Altered Corneal Epithelium Circadian Rhythm in Mice with Streptozotocin-induced Type 1 Diabetes.

    PubMed

    Song, Fang; Xue, Yunxia; Dong, Dong; Liu, Jun; Fu, Ting; Xiao, Chengju; Wang, Hanqing; Lin, Cuipei; Liu, Peng; Zhong, Jiajun; Yang, Yabing; Wang, Zhaorui; Pan, Hongwei; Chen, Jiansu; Li, Yangqiu; Cai, Dongqing; Li, Zhijie

    2016-01-01

    The mechanisms of corneal epithelial lesions and delayed wound repair, as well as their association with diabetes mellitus, are critical issues for clinical ophthalmologists. To test whether the diabetic condition alters the circadian rhythm in a mouse cornea and whether insulin can synchronise the corneal clock, we studied the effects of streptozotocin-induced diabetes on the mitosis of epithelial cells, the recruitment of leukocytes to the cornea, and the expression of main core clock genes (Clock, Bmal1, Per2, Cry1, and Rev-erbα) in the corneal epithelium. We also assessed the possible effect of insulin on these modifications. Diabetes downregulated Clock, Bmal1, and Per2 expression, upregulated Cry1 and Rev-erbα expression, reduced corneal epithelial mitosis, and increased leukocyte (neutrophils and γδ T-cells) recruitment to the cornea. Early treatments with insulin partially restored the altered rhythmicity in the diabetic cornea. In conclusion, insulin-dependent diabetes altered the normal rhythmicity of the cornea, and insulin administration had a beneficial effect on restoring normal rhythmicity in the diabetic cornea. PMID:27611469

  3. Nanoparticles that deliver triplex-forming peptide nucleic acid molecules correct F508del CFTR in airway epithelium.

    PubMed

    McNeer, Nicole Ali; Anandalingam, Kavitha; Fields, Rachel J; Caputo, Christina; Kopic, Sascha; Gupta, Anisha; Quijano, Elias; Polikoff, Lee; Kong, Yong; Bahal, Raman; Geibel, John P; Glazer, Peter M; Saltzman, W Mark; Egan, Marie E

    2015-04-27

    Cystic fibrosis (CF) is a lethal genetic disorder most commonly caused by the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. It is not readily amenable to gene therapy because of its systemic nature and challenges including in vivo gene delivery and transient gene expression. Here we use triplex-forming peptide nucleic acids and donor DNA in biodegradable polymer nanoparticles to correct F508del. We confirm modification with sequencing and a functional chloride efflux assay. In vitro correction of chloride efflux occurs in up to 25% of human cells. Deep-sequencing reveals negligible off-target effects in partially homologous sites. Intranasal delivery of nanoparticles in CF mice produces changes in the nasal epithelium potential difference assay, consistent with corrected CFTR function. Also, gene correction is detected in the nasal and lung tissue. This work represents facile genome engineering in vivo with oligonucleotides using a nanoparticle system to achieve clinically relevant levels of gene editing without off-target effects.

  4. Insulin Restores an Altered Corneal Epithelium Circadian Rhythm in Mice with Streptozotocin-induced Type 1 Diabetes

    PubMed Central

    Song, Fang; Xue, Yunxia; Dong, Dong; Liu, Jun; Fu, Ting; Xiao, Chengju; Wang, Hanqing; Lin, Cuipei; Liu, Peng; Zhong, Jiajun; Yang, Yabing; Wang, Zhaorui; Pan, Hongwei; Chen, Jiansu; Li, Yangqiu; Cai, Dongqing; Li, Zhijie

    2016-01-01

    The mechanisms of corneal epithelial lesions and delayed wound repair, as well as their association with diabetes mellitus, are critical issues for clinical ophthalmologists. To test whether the diabetic condition alters the circadian rhythm in a mouse cornea and whether insulin can synchronise the corneal clock, we studied the effects of streptozotocin-induced diabetes on the mitosis of epithelial cells, the recruitment of leukocytes to the cornea, and the expression of main core clock genes (Clock, Bmal1, Per2, Cry1, and Rev-erbα) in the corneal epithelium. We also assessed the possible effect of insulin on these modifications. Diabetes downregulated Clock, Bmal1, and Per2 expression, upregulated Cry1 and Rev-erbα expression, reduced corneal epithelial mitosis, and increased leukocyte (neutrophils and γδ T-cells) recruitment to the cornea. Early treatments with insulin partially restored the altered rhythmicity in the diabetic cornea. In conclusion, insulin-dependent diabetes altered the normal rhythmicity of the cornea, and insulin administration had a beneficial effect on restoring normal rhythmicity in the diabetic cornea. PMID:27611469

  5. Expression of semaphorin 3A in the rat corneal epithelium during wound healing

    SciTech Connect

    Morishige, Naoyuki; Ko, Ji-Ae; Morita, Yukiko; Nishida, Teruo

    2010-05-14

    The neural guidance protein semaphorin 3A (Sema3A) is expressed in corneal epithelial cells of the adult rat. We have now further investigated the localization of Sema3A in the normal rat corneal epithelium as well as changes in its expression pattern during wound healing after central corneal epithelial debridement. The expression pattern of Sema3A was compared with that of the tight-junction protein zonula occludens-1 (ZO-1), the gap-junction protein connexin43 (Cx43), or the cell proliferation marker Ki67. Immunofluorescence analysis revealed that Sema3A was present predominantly in the membrane of basal and wing cells of the intact corneal epithelium. The expression of Sema3A at the basal side of basal cells was increased in the peripheral epithelium compared with that in the central region. Sema3A was detected in all layers at the leading edge of the migrating corneal epithelium at 6 h after central epithelial debridement. The expression of Sema3A was markedly up-regulated in the basal and lateral membranes of columnar basal cells apparent in the thickened, newly healed epithelium at 1 day after debridement, but it had largely returned to the normal pattern at 3 days after debridement. The expression of ZO-1 was restricted to superficial epithelial cells and remained mostly unchanged during the wound healing process. The expression of Cx43 in basal cells was down-regulated at the leading edge of the migrating epithelium but was stable in the remaining portion of the epithelium. Ki67 was not detected in basal cells of the central epithelium at 1 day after epithelial debridement, when Sema3A was prominently expressed. Immunoblot analysis showed that the abundance of Sema3A in the central cornea was increased 1 day after epithelial debridement, whereas that of ZO-1 or Cx43 remained largely unchanged. This increase in Sema3A expression was accompanied by up-regulation of the Sema3A coreceptor neuropilin-1. Our observations have thus shown that the expression of

  6. Intrachoroidal Neovascularization in Transgenic Mice Overexpressing Vascular Endothelial Growth Factor in the Retinal Pigment Epithelium

    PubMed Central

    Schwesinger, Catherine; Yee, Charles; Rohan, Richard M.; Joussen, Antonia M.; Fernandez, Antonio; Meyer, Tobias N.; Poulaki, Vassiliki; Ma, Joseph J. K.; Redmond, T. Michael; Liu, Suyan; Adamis, Anthony P.; D’Amato, Robert J.

    2001-01-01

    Choroidal neovascularization in age-related macular degeneration is a frequent and poorly treatable cause of vision loss in elderly Caucasians. This choroidal neovascularization has been associated with the expression of vascular endothelial growth factor (VEGF). In current animal models choroidal neovascularization is induced by subretinal injection of growth factors or vectors encoding growth factors such as VEGF, or by disruption of the Bruch’s membrane/retinal pigment epithelium complex with laser treatment. We wished to establish a transgenic murine model of age-related macular degeneration, in which the overexpression of VEGF by the retinal pigment epithelium induces choroidal neovascularization. A construct consisting of a tissue-specific murine retinal pigment epithelium promoter (RPE65 promoter) coupled to murine VEGF164 cDNA with a rabbit β-globin-3′ UTR was introduced into the genome of albino mice. Transgene mRNA was expressed in the retinal pigment epithelium at all ages peaking at 4 months. The expression of VEGF protein was increased in both the retinal pigment epithelium and choroid. An increase of intravascular adherent leukocytes and vessel leakage was observed. Histopathology revealed intrachoroidal neovascularization that did not penetrate through an intact Bruch’s membrane. These results support the hypothesis that additional insults to the integrity of Bruch’s membrane are required to induce growth of choroidal vessels into the subretinal space as seen in age-related macular degeneration. This model may be useful to screen for inhibitors of choroidal vessel growth. PMID:11238064

  7. Postnatal epithelium and mesenchyme stem/progenitor cells in bioengineered amelogenesis and dentinogenesis

    PubMed Central

    Jiang, Nan; Zhou, Jian; Chen, Mo; Schiff, Michael D.; Lee, Chang H.; Kong, Kimi; Embree, Mildred C.; Zhou, Yanheng; Mao, Jeremy J.

    2014-01-01

    Rodent incisors provide a classic model for studying epithelial-mesenchymal interactions in development. However, postnatal stem/progenitor cells in rodent incisors have not been exploited for tooth regeneration. Here, we characterized postnatal rat incisor epithelium and mesenchyme stem/progenitor cells and found that they formed enamel- and dentin-like tissues in vivo. Epithelium and mesenchyme cells were harvested separately from the apical region of postnatal 4–5 day rat incisors. Epithelial and mesenchymal phenotypes were confirmed by immunocytochemistry, CFU assay and/or multi-lineage differentiation. CK14+, Sox2+ and Lgr5+ epithelium stem cells from the cervical loop significantly enhanced amelogenin and ameloblastin expression upon BMP4 or FGF3 stimulation, signifying their differentiation towards ameloblast-like cells, whereas mesenchyme stem/progenitor cells upon BMP4, BMP7 and Wnt3a treatment robustly expressed Dspp, a hallmark of odontoblastic differentiation. We then control-released microencapsulated BMP4, BMP7 and Wnt3a in transplants of epithelium and mesenchyme stem/progenitor cells in the renal capsule of athymic mice in vivo. Enamel and dentin-like tissues were generated in two integrated layers with specific expression of amelogenin and ameloblastin in the newly formed, de novo enamel-like tissue, and DSP in dentin-like tissue. These findings suggest that postnatal epithelium and mesenchyme stem/progenitor cells can be primed by pivotal signals towards bioengineered tooth regeneration. PMID:24345734

  8. Differential Expression Patterns of EGF, EGFR, and ERBB4 in Nasal Polyp Epithelium

    PubMed Central

    Zhao, Li; Subramaniam, Somasundaram; Yu, Xue Min; Li, Ying Ying; Chen, De Hua; Li, Tian Ying; Shen, Liang; Shi, Li; Wang, De Yun

    2016-01-01

    Epidermal growth factor receptors play an important role in airway epithelial cell growth and differentiation. The current study investigates the expression profiles of EGF, EGFR and ERBB4 in patients with nasal polyps (NP), and their response to glucocorticosteroid (GC) treatment. Fifty patients with NP (40 without GC treatment and 10 with oral GC) and 20 control subjects with septal deviation were recruited into the study. Protein levels of EGF, EGFR, and ERBB4 were evaluated by immune-staining. In healthy nasal epithelium, EGF and EGFR localized within p63+ basal cells, while ERBB4 localized within ciliated cells. GC-naïve NP epithelium showed weak expression of EGF in 90% of samples versus 5% of controls. EGFR was significantly increased in the epithelium with basal cell hyperplasia from GC-naïve NPs (78%, 31/40) compared to controls (23%, 4/17). EGFR was also found in some degranulating goblet cells. ERBB4 expression was significantly higher in hyperplastic epithelium from GC-naïve NPs (65%, 26/40) than in controls (6%, 1/17). GC treatment restored the EGF expression and normalized the EGFR and ERBB4 expression in NPs. Differential expression patterns of EGF, EGFR, and ERBB4 are essential in epithelial restitution and remodeling in nasal epithelium. PMID:27285994

  9. Cloning and localization of two multigene receptor families in goldfish olfactory epithelium

    PubMed Central

    Cao, Yanxiang; Oh, Bryan C.; Stryer, Lubert

    1998-01-01

    Goldfish reproduction is coordinated by pheromones that are released by ovulating females and detected by males. Two highly potent pheromones, a dihydroxyprogesterone and a prostaglandin, previously have been identified, and their effects on goldfish behavior have been studied in depth. We have cloned goldfish olfactory epithelium cDNAs belonging to two multigene G-protein coupled receptor families as a step toward elucidating the molecular basis of pheromone recognition. One gene family (GFA) consists of homologs of putative odorant receptors (≈320 residues) found in the olfactory epithelium of other fish and mammals. The other family (GFB) consists of homologs of putative pheromone receptors found in the vomeronasal organ (VNO) of mammals and also in the nose of pufferfish. GFB receptors (≈840 residues) are akin to the V2R family of VNO receptors, which possess a large extracellular N-terminal domain and are homologs of calcium-sensing and metabotropic glutamate receptors. In situ hybridization showed that the two families of goldfish receptors are differentially expressed in the olfactory epithelium. GFB mRNA is abundant in rather compact cells whose nuclei are near the apical surface. In contrast, GFA mRNA is found in elongated cells whose nuclei are positioned deeper in the epithelium. Our findings support the hypothesis that the separate olfactory organ and VNO of terrestrial vertebrates arose in evolution by the segregation of distinct classes of neurons that were differentially positioned in the olfactory epithelium of a precursor aquatic vertebrate. PMID:9751777

  10. Quantitative electron microscopic analysis of the epithelium of normal human alveolar mucosa.

    PubMed

    Bernimoulin, J P; Schroeder, H E

    1977-05-31

    The epithelium of normal human alveolar mucosa originating from the anterior vestibulum was subjected to stereologic analysis. Eight biopsies were collected half-way between the muco gingival junction and the vestibular fornix from 20 to 50 year-old females, and processed for light and electron microscopy. At two levels of magnification, electron micrographs were sampled from four artificially selected strata in regions of epithelial ridges. Stereologic point counting based on a computer-aided system for analyzing stratified epithelia served for examining a total of about 860 electron micrographs. The alveolar epithelium was 0.26 mm thick, occasionally interdigitated by short, slender connective tissue papillae, and consisted of (1) a narrow basal and suprabasal, and (2) a broad spinous and surface compartment. It displayed a differentiation pattern which, in most subjects studied, was similar to that of normal human buccal epithelium, however, on the average, produced less mature surface cells. This pattern was expressed mainly by a density increase of cytoplasmic filaments (98 A in diameter), a concomitant decrease of the cytoplasmic ground substance, the formation of dark-cored membrane coating granules, and invividually variable amounts of glycogen deposition. In some subjects, a mixed differentiation pattern was found. The structural organization of alveolar epithelium, in analogy to cheek epithelium, was compatible with the function of distensibility.

  11. Regionalisation of early head ectoderm is regulated by endoderm and prepatterns the orofacial epithelium.

    PubMed

    Haworth, Kim E; Healy, Christopher; Morgan, Pamela; Sharpe, Paul T

    2004-10-01

    The oral epithelium becomes regionalised proximodistally early in development, and this is reflected by the spatial expression of signalling molecules such as Fgf8 and Bmp4. This regionalisation is responsible for regulating the spatial expression of genes in the underlying mesenchyme. These genes are required for the spatial patterning of bone, cartilage orofacial development and, in mammals, teeth. The mechanism and timing of this important regionalisation during head epithelium development are not known. Using lipophilic dyes to fate map the oral epithelium in chick embryos, we show that the cells that will occupy the epithelium of the distal and the proximal mandible primordium already occupy different spatial locations in the developing head ectoderm prior to the formation of the first pharyngeal arch and neural crest migration. Moreover, the ectoderm cells fated to become proximal oral epithelium express Fgf8 and this expression requires the presence of endoderm. Thus, the first fundamental patterning process in jaw morphogenesis is controlled by the early separation of specific areas of ectoderm that are regulated by ectoderm-endoderm interactions, and does not involve neural crest cells.

  12. Genetic modification and genetic determinism

    PubMed Central

    Resnik, David B; Vorhaus, Daniel B

    2006-01-01

    In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

  13. Endogenous antioxidants and nasal human epithelium response to air pollutants: genotoxic and inmmuno-cytochemical evaluation.

    PubMed

    Fortoul, T I; Rojas-Lemus, M; Avila-Casado, M C; Rodriguez-Lara, V; Montaño, L F; Muñoz-Comonfort, A; Lopez-Zepeda, L S

    2010-10-01

    Nasal epithelium is a source for identifying atmospheric pollution impact. Antioxidants play a relevant role in the protection of the cells from environmental injury, but scarce information is available about the interaction of endogenous antioxidants and genotoxic damage in nasal epithelium from urban populations highly exposed to traffic-generated air pollutants. An immunocytochemical and genotoxic evaluation was implemented in nasal cell epithelium in a population chronically exposed to atmospheric pollution from autumn 2004 to autumn 2005. Superoxide dismutase (SOD) and Catalase (CAT) were evaluated in nasal scrapings by morphometry and genotoxicity by comet assay. An increase in DNA damage correlates with a decrease in SOD and CAT in nasal cells during autumn and the inverse result was observed during summer (R = 0.88). Not only should exogenous antioxidant supplements be encouraged, but also a healthy diet to strengthen intracellular defenses against oxidative stress induced by exposure to air pollutants. PMID:20981858

  14. When Insult Is Added to Injury: Cross Talk between ILCs and Intestinal Epithelium in IBD

    PubMed Central

    2016-01-01

    Inflammatory bowel disease (IBD) is characterized by an impairment of the integrity of the mucosal epithelial barrier, which causes exacerbated inflammation of the intestine. The intestinal barrier is formed by different specialized epithelial cells, which separate the intestinal lumen from the lamina propria. In addition to its crucial role in protecting the body from invading pathogens, the intestinal epithelium contributes to intestinal homeostasis by its biochemical properties and communication to underlying immune cells. Innate lymphoid cells (ILCs) are a recently described population of lymphocytes that have been implicated in both mucosal homeostasis and inflammation. Recent findings indicate a critical feedback loop in which damaged epithelium activates these innate immune cells to restore epithelial barrier function. This review will focus on the signalling pathways between damaged epithelium and ILCs involved in repair of the epithelial barrier and tissue homeostasis and the relationship of these processes with the control of IBD. PMID:27578924

  15. Role of GATA factors in development, differentiation, and homeostasis of the small intestinal epithelium

    PubMed Central

    Aronson, Boaz E.; Stapleton, Kelly A.

    2014-01-01

    The small intestinal epithelium develops from embryonic endoderm into a highly specialized layer of cells perfectly suited for the digestion and absorption of nutrients. The development, differentiation, and regeneration of the small intestinal epithelium require complex gene regulatory networks involving multiple context-specific transcription factors. The evolutionarily conserved GATA family of transcription factors, well known for its role in hematopoiesis, is essential for the development of endoderm during embryogenesis and the renewal of the differentiated epithelium in the mature gut. We review the role of GATA factors in the evolution and development of endoderm and summarize our current understanding of the function of GATA factors in the mature small intestine. We offer perspective on the application of epigenetics approaches to define the mechanisms underlying context-specific GATA gene regulation during intestinal development. PMID:24436352

  16. A note on langerhans cells in the oesophagus epithelium of domesticated mammals.

    PubMed

    Meyer, W; Hornickel, I; Schoennagel, B

    2010-04-01

    Using the zinc-iodide osmium tetroxide (ZIO) method, TEM and immunohistochemistry (for CD1a and langerin), the study demonstrates Langerhans cells in the oesophageal epithelium of domesticated mammals (herbivores: horse, cattle, goat; omnivores: pig, dog, laboratory rat; carnivores: cat), although with variations between the species. The ZIO method and TEM showed this cell type in the cat and, sporadically, in the horse; CD1a (+) Langerhans cells were demonstrated in the ovine, porcine and murine oesophagus. Positive staining for langerin was detected in single cells of the caprine, canine, murine and feline oesophagus and more distinct in almost all the cell layers of the equine and porcine oesophagus epithelium. The findings are discussed comparing specifically the results for CD1a and langerin, whereby the latter C-type lectin may be of importance in species with a rather thick oesophagus epithelium, such as that present in the plantivorous and most of the omnivorous animals, where antigenic pressure is reduced.

  17. Morphological variations and population density of membrane-coating granules in human gingival sulcular epithelium.

    PubMed

    Braun, T B; Ashrafi, S H; Waterhouse, J P

    1990-01-01

    Surgically excised specimens of sulcular wall with minimal inflammatory response as judged by clinical then histological criteria were processed for electron microscopy. The specimens were divided into crestal, middle and cervical areas of the sulcular epithelium. The highest concentration of membrane-coating granules was found in the upper spinous cell layers of sulcular epithelium. The profiles of these granules showed examples of both classical keratinized (lamellated) and non-keratinized (non-lamellated) forms but also other appearances that were not derived from them through differences in the plane of section. The population of granules decreased between the crestal and cervical zones, and the decrease in number was marked for the lamellated granules. This decrease in numbers of membrane-coating granules, together with the wider intercellular spaces, may be the reason why the sulcular epithelium is most permeable in the cervical region.

  18. Engineering functional epithelium for regenerative medicine and in vitro organ models: a review.

    PubMed

    Vrana, Nihal E; Lavalle, Philippe; Dokmeci, Mehmet R; Dehghani, Fariba; Ghaemmaghami, Amir M; Khademhosseini, Ali

    2013-12-01

    Recent advances in the fields of microfabrication, biomaterials, and tissue engineering have provided new opportunities for developing biomimetic and functional tissues with potential applications in disease modeling, drug discovery, and replacing damaged tissues. An intact epithelium plays an indispensable role in the functionality of several organs such as the trachea, esophagus, and cornea. Furthermore, the integrity of the epithelial barrier and its degree of differentiation would define the level of success in tissue engineering of other organs such as the bladder and the skin. In this review, we focus on the challenges and requirements associated with engineering of epithelial layers in different tissues. Functional epithelial layers can be achieved by methods such as cell sheets, cell homing, and in situ epithelialization. However, for organs composed of several tissues, other important factors such as (1) in vivo epithelial cell migration, (2) multicell-type differentiation within the epithelium, and (3) epithelial cell interactions with the underlying mesenchymal cells should also be considered. Recent successful clinical trials in tissue engineering of the trachea have highlighted the importance of a functional epithelium for long-term success and survival of tissue replacements. Hence, using the trachea as a model tissue in clinical use, we describe the optimal structure of an artificial epithelium as well as challenges of obtaining a fully functional epithelium in macroscale. One of the possible remedies to address such challenges is the use of bottom-up fabrication methods to obtain a functional epithelium. Modular approaches for the generation of functional epithelial layers are reviewed and other emerging applications of microscale epithelial tissue models for studying epithelial/mesenchymal interactions in healthy and diseased (e.g., cancer) tissues are described. These models can elucidate the epithelial/mesenchymal tissue interactions at the

  19. Effect of ozone treatment on airway reactivity and epithelium-derived relaxing factor in guinea pigs.

    PubMed

    Fedan, J S; Millecchia, L L; Johnston, R A; Rengasamy, A; Hubbs, A; Dey, R D; Yuan, L X; Watson, D; Goldsmith, W T; Reynolds, J S; Orsini, L; Dortch-Carnes, J; Cutler, D; Frazer, D G

    2000-06-01

    Ozone (O(3)) is toxic to respiratory epithelium and causes airway inflammation and hyperreactivity. To evaluate the role of the epithelium in the development of hyperreactivity, we examined in guinea pigs the effects of inhaled O(3) (3 ppm for 1 h; 0-24 h after exposure) on 1) reactivity to inhaled methacholine (MCh), 2) reactivity of the isolated, perfused trachea (IPT) to MCh, 3) epithelium-derived relaxing factor (EpDRF)-mediated relaxations of IPT induced by mucosal hyperosmolar solutions, 4) neurogenic contraction and relaxation responses, 5) transepithelial potential difference, and 6) microscopic analysis of nitrotyrosine immunofluorescence, substance P fiber density, and tracheal morphology. At 0 h, O(3) caused hyperreactivity to inhaled MCh and mucosally but not serosally applied MCh in IPT (only in the presence of the epithelium) and a decrease in transepithelial potential difference. Inhibition of EpDRF-induced relaxation responses occurred at 2 h. All of these changes returned to control by 12 to 18 h. O(3) had no effect on neurogenic responses. Nitrotyrosine immunofluorescence appeared in the trachea at 0 h in detached epithelial cell ghosts and in intrapulmonary airways by 6 h. Substance P fiber density was elevated in smooth muscle at 0 and 18 h but not in epithelium or lamina propria of intrapulmonary and extrapulmonary bronchi. Loss of cilia and mucosubstances in the mucosa occurred at 0 h; the epithelium became markedly attenuated over 12 to 24 h. A reversible increase in epithelial permeability and a decrease in EpDRF production may contribute to O(3)-induced hyperreactivity to MCh. PMID:10869370

  20. [Carcinogenic and promoting effects of fish juice, preserved rice and salted dry fish on the forestomach epithelium of mice and esophageal epithelium of rats].

    PubMed

    Lin, P Z; Zhang, J S; Ding, Z W; Cai, H Y

    1986-09-01

    The carcinogenic and promoting effects of fish juice, preserved rice and salted dry fish from Nanau county, Guangdong province, a high incidence area of esophageal cancer, were studied in mice and rats. The homemade fish juice as well as fish juice in market, whether or not added with NaNO2, did not cause tumor in the forestomach of mice and the esophagus of rats. When the mice were intubated with an initiator, nitrososarcosinethylester (NSEE) twice, no carcinoma was found at the end of the experiment (D 120). Only papilloma appeared in the forestomach epithelium. The incidence was only 37.5%. However, when the mice were intubated with NSEE for 2 times followed by gastric doses of homemade fish juice, the tumor incidence in the forestomach was increased to 89.7%, in which 20.5% was carcinoma. The tumor and carcinoma incidences of initiator (NSEE and NMBzA) group and initiator + market fish juice group in mice and rats were without significant difference. The experimental results show that the homemade fish juice proved distinct promoting effect on the process of cocarcinogenesis initiated by NSEE in the forestomach of mice, while the market fish juice has no significant promoting effect on the forestomach epithelium of mice and the esophageal epithelium of rats. NSEE induced 31.6% carcinoma in the forestomach epithelium of mice on standard diet. While in mice fed with preserved rice and salted dry fish, the carcinoma incidence was increased to 63.6%. It appears that preserved rice and salted dry fish have promoting effect on the process of cocarcinogenesis initiated by NSEE in the forestomach of mice.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3568985

  1. Hyperopic correction: clinical validation with epithelium-on and epithelium-off protocols, using variable fluence and topographically customized collagen corneal crosslinking

    PubMed Central

    Kanellopoulos, Anastasios John; Asimellis, George

    2014-01-01

    Purpose To report novel application of topographically-customized collagen crosslinking aiming to achieve hyperopic refractive changes. Two approaches were evaluated, one based on epithelium-off and one based on epithelium-on (transepithelial). Methods A peripheral annular-shaped topographically customizable design was employed for high-fluence ultraviolet (UV)-A irradiation aiming to achieve hyperopic refractive changes. A total of ten eyes were involved in this study. In group-A (five eyes), a customizable ring pattern was employed to debride the epithelium by excimer laser ablation, while in group-B (also five eyes), the epithelium remained intact. In both groups, specially formulated riboflavin solutions were applied. Visual acuity, cornea clarity, keratometry, topography, and pachymetry with a multitude of modalities, as well as endothelial cell counts were evaluated. Results One year postoperatively, the following changes have been noted: in group-A, average uncorrected distance visual acuity changed from 20/63 to 20/40. A mean hyperopic refractive increase of +0.75 D was achieved. There was some mild reduction in the epithelial thickness. In group-B, average uncorrected distance visual acuity changed from 20/70 to 20/50. A mean hyperopic refractive increase of +0.85 D was achieved. Epithelial thickness returned to slightly reduced levels (compared to baseline) in group-A, whereas to slightly increased levels in group-B. Conclusion We introduce herein the novel application of a topographically-customizable collagen crosslinking to achieve a hyperopic refractive effect. This novel technique may be applied either with epithelial removal, offering a more stable result or with a non-ablative and non-incisional approach, offering a minimally invasive alternative. PMID:25506204

  2. Lumican binds ALK5 to promote epithelium wound healing.

    PubMed

    Yamanaka, Osamu; Yuan, Yong; Coulson-Thomas, Vivien Jane; Gesteira, Tarsis Ferreira; Call, Mindy K; Zhang, Yujin; Zhang, Jianhua; Chang, Shao-Hsuan; Xie, Changchun; Liu, Chia-Yang; Saika, Shizuya; Jester, James V; Kao, Winston W-Y

    2013-01-01

    Lumican (Lum), a small leucine-rich proteoglycan (SLRP) family member, has multiple matricellular functions both as an extracellular matrix component and as a matrikine regulating cell proliferation, gene expression and wound healing. To date, no cell surface receptor has been identified to mediate the matrikine functions of Lum. This study aimed to identify a perspective receptor that mediates Lum effects on promoting wound healing. Transforming growth factor-β receptor 1 (ALK5) was identified as a potential Lum-interacting protein through in silico molecular docking and molecular dynamics. This finding was verified by biochemical pull-down assays. Moreover, the Lum function on wound healing was abrogated by an ALK5-specific chemical inhibitor as well as by ALK5 shRNAi. Finally, we demonstrated that eukaryote-specific post-translational modifications are not required for the wound healing activity of Lum, as recombinant GST-Lum fusion proteins purified from E. coli and a chemically synthesized LumC13 peptide (the last C-terminal 13 amino acids of Lum) have similar effects on wound healing in vitro and in vivo.

  3. Genesis of cilia and microvilli of rat nasal epithelia during prenatal development. III. Respiratory epithelium surface, including a comparison with the surface of the olfactory epithelium.

    PubMed Central

    Menco, B P; Farbman, A I

    1987-01-01

    During prenatal development the respiratory epithelium surface of the rat's nasal septum underwent the following changes. At intra-uterine day E14 there was a transformation from State I, cells with primary cilia only, to cells which also had microvilli (Stage II). Anterior parts of the nasal septum retained microvilli throughout further development. Posteriorly, centriole multiplication (Stage III) and formation of shafts of secondary cilia (Stage IV) occurred from around E16 and E18 onwards, respectively. From E18 to E20 numbers of cells with cilia increased at an overall rate of about 6 X 10(6) cells/cm2/day. Respiratory cilia and microvilli grew, on average, by about 0.3 micron/day and 0.1 micron/day, respectively. At Stage V, beginning around E19, the cilia became aligned within cells and, at Stage VI, beginning around E21, became synchronised between cells. Respiratory ciliogenesis in the nose is most precocious near the olfactory epithelium. The formation of respiratory cilia starts after that of olfactory cilia. However, unlike olfactory epithelium surfaces those of ciliated respiratory epithelia resembled those of adults around birth. Images Figs. 1-4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 PMID:3654366

  4. The effect of acetzolamide on Ion transport across isolated sheep rumen epithelium.

    PubMed

    Emanović, D; Harrison, F A; Keynes, R D; Rankin, J C

    1976-01-01

    1. The net fluxes of sodium and chloride from the lumen to the blood side of isolated sheep rumen epithelium were reduced by treatment of both sides of the epithelium with acetazolamide. 2. The changes in the net fluxes of sodium and chloride were significantly correlated and showed recovery after removal of acetazolamide. 3. The net flux of potassium from blood to lumen side of the epithelim was not affected by treatment with acetazolamide. 4. It is suggested that acetazolamide blocks coupled sodium and chloride transport which may be mediated through 'low-activity' carbonic anhydrase enzymes.

  5. Biochemical analysis of the stress protein response in human oesophageal epithelium

    PubMed Central

    Hopwood, D; Moitra, S; Vojtesek, B; Johnston, D; Dillon, J; Hupp, T

    1997-01-01

    Background—The oesophageal epithelium is exposed routinely to noxious agents in the environment, including gastric acid, thermal stress, and chemical toxins. These epithelial cells have presumably evolved effective protective mechanisms to withstand tissue damage and repair injured cells. Heat shock protein or stress protein responses play a central role in protecting distinct cell types from different types of injury. 
Aim—To determine (i) whether biochemical analysis of stress protein responses in pinch biopsy specimens from human oesophageal epithelium is feasible; (ii) whether undue stresses are imposed on cells by the act of sample collection, thus precluding analysis of stress responses; and (iii) if amenable to experimentation, the type of heat shock protein (Hsp) response that operates in the human oesophageal epithelium. 
Methods—Tissue from the human oesophagus comprised predominantly of squamous epithelium was acquired within two hours of biopsy and subjected to an in vitro heat shock. Soluble tissue cell lysates derived from untreated or heat shocked samples were examined using denaturing polyacrylamide gel electrophoresis for changes in: (i) the pattern of general protein synthesis by labelling epithelial cells with 35S-methionine and (ii) the levels of soluble Hsp70 protein and related isoforms using immunochemical protein blots. 
Results—A single pinch biopsy specimen is sufficient to extract and analyse specific sets of polypeptides in the oesophageal epithelium. After ex vivo heat shock, a classic inhibition of general protein synthesis is observed and correlates with the increased synthesis of two major proteins of molecular weight of 60 and 70 kDa. Notably, cells from unheated controls exhibit a "stressed" biochemical state 22 hours after incubation at 37°C, as shown by inhibition of general protein synthesis and increased synthesis of the 70 kDa protein. These data indicate that only freshly acquired specimens are suitable for

  6. Effects of vocal fold epithelium removal on vibration in an excised human larynx model.

    PubMed

    Tse, Justin R; Zhang, Zhaoyan; Long, Jennifer L

    2015-07-01

    This study investigated the impact of selective epithelial injury on phonation in an excised human larynx apparatus. With intact epithelium, the vocal folds exhibited a symmetrical vibration pattern with complete glottal closure during vibration. The epithelium was then enzymatically removed from one, then both vocal folds, which led to left-right asymmetric vibration and a decreased closed quotient. Although the mechanisms underlying these vibratory changes are unclear, these results demonstrate that some component of an intact surface layer may play an important role in achieving normal symmetric vibration and glottal closure.

  7. [Cytological study of gum epithelium in connection with diabetes mellitus compensation stage].

    PubMed

    Ashurov, G G; Dzhuraeva, Sh F

    2009-01-01

    The structure of interphased nuclei of gum's epithelium and inflammation of periodontal structure in patients with glycolitic disorders in coonection of degree compensation of diabetes mellitus were studied. In patients with diabetes mellitus and inflammation of gum mucosa 67,33+/-0,05% of gum's cells epithelium had morphology changes nuclei from the date of control group (50,99+/-0,05%) patients. This difference were more essential at deterioration of compensation (62,03+/-0,08%), sub - (67,05+/-0,05%), decompensate (75,11+/-0,07%) diabetes mellitus. PMID:19491782

  8. Phagocytosis of cells in the gastric surface epithelium of the rat.

    PubMed

    Morris, G P; Harding, R K

    1979-02-28

    Gastric surface epithelial cells (SEC) from fed rats, from rats fasted for 16 h and from mucosae exposed in an ex-vivo chamber to 16 mM aspirin for 5 min were examined by transmission electron microscopy. SEC have the capability to phagocytose adjacent epithelial cells and parietal cells. Phagocytosis is rare in mucosae from fasted animals but common in fed animals or after brief exposure to aspirin. Phagocytic capabilities are not restricted to the progenitor zone but exist throughout the surface epithelium. Phagocytosis may provide a mechanism for the removal of damaged or senescent cells from the surface epithelium.

  9. Transplantation tool integrated with MEMS manipulator for retinal pigment epithelium cell sheet.

    PubMed

    Wada, H; Konishi, S

    2013-01-01

    This paper reports a transplantation tool for the retinal pigment epithelium in an eye. We have developed MEMS manipulator as an end-effector for transplantation of retinal pigment epithelium cell sheet. Typical size of MEMS manipulator is 3mm×3mm. MEMS manipulator was made of polydimethylsiloxane and driven by pneumatic balloon actuators. MEMS manipulator have been improved and integrated with several functions by sensors and actuators. MEMS manipulator is integrated into a transplantation tool. A whole tool also requires improvements based on our experimental results. We have improved our tool in terms of assembling, sealing, and operation. PMID:24109649

  10. Snai1 regulates cell lineage allocation and stem cell maintenance in the mouse intestinal epithelium

    PubMed Central

    Horvay, Katja; Jardé, Thierry; Casagranda, Franca; Perreau, Victoria M; Haigh, Katharina; Nefzger, Christian M; Akhtar, Reyhan; Gridley, Thomas; Berx, Geert; Haigh, Jody J; Barker, Nick; Polo, Jose M; Hime, Gary R; Abud, Helen E

    2015-01-01

    Snail family members regulate epithelial-to-mesenchymal transition (EMT) during invasion of intestinal tumours, but their role in normal intestinal homeostasis is unknown. Studies in breast and skin epithelia indicate that Snail proteins promote an undifferentiated state. Here, we demonstrate that conditional knockout of Snai1 in the intestinal epithelium results in apoptotic loss of crypt base columnar stem cells and bias towards differentiation of secretory lineages. In vitro organoid cultures derived from Snai1 conditional knockout mice also undergo apoptosis when Snai1 is deleted. Conversely, ectopic expression of Snai1 in the intestinal epithelium in vivo results in the expansion of the crypt base columnar cell pool and a decrease in secretory enteroendocrine and Paneth cells. Following conditional deletion of Snai1, the intestinal epithelium fails to produce a proliferative response following radiation-induced damage indicating a fundamental requirement for Snai1 in epithelial regeneration. These results demonstrate that Snai1 is required for regulation of lineage choice, maintenance of CBC stem cells and regeneration of the intestinal epithelium following damage. PMID:25759216

  11. [Regulatory elements in the skin epithelium of Saccoglossus mereschkowskii (Enteropneusta, Hemichordata): electron microscopic and immunocytochemical study].

    PubMed

    Stoliarova, M V; Val'kovich, E I

    2013-01-01

    The aim of this investigation was to demonstrate the regulatory elements in the skin epithelium of Enteropneusta which are supposed to be related to the chordate ancestors. Using electron microscopy, it was found that in the skin epithelium of a representative of enteropneusts Saccoglossus mereschkowskii, the basal parts of some epitheliocytes took part in formation of a nerve layer. These cells were considered as receptor ciliated cells. The granular epithelial cells were shown to release secretion according to both exocrine and endocrine mechanism; these cells were characterized as endocrine-like regulatory cells. Fine granular cells possibly represent special receptor-endocrine-like cell type. The immunocytochemical detection of FMRFamid neuropeptide localization in histological sections confirmed the electron microscopic data on the presence of receptor and endocrine-like cells in the epithelium. It is suggested that the skin epithelium of Enteropneusta contains a peculiar neuro-endocrine regulatory system that is represented by receptor cells, receptor-endocrine-like cells of an open type and nerve elements of the nerve layer. PMID:24707736

  12. The metaplastic effects of estrogen on mouse prostate epithelium: proliferation of cells with basal cell phenotype.

    PubMed

    Risbridger, G P; Wang, H; Frydenberg, M; Cunha, G

    2001-06-01

    The exogenous administration of estrogens to male mice alters the hypothalamic-pituitary-gonadal axis and reduces androgen levels, leading to a regression of the prostatic epithelium. As well, a specific direct response to estrogens is the induction of epithelial squamous metaplasia. The aims of this study were to identify the process by which the prostatic epithelium is transformed in intact adult male mice using the synthetic estrogen, diethylstilbestrol. A comparison of the effects of diethylstilbestrol in the three lobes revealed a hierarchy of response, with the anterior lobe being the most responsive, the dorsolateral lobe less responsive, and the ventral lobe the least responsive. The effect of castration was used to distinguish between the epithelial responses to estrogen administration and androgen deprivation. The results demonstrate that transformation of the epithelium involved proliferation of cells with a basal cell phenotype, the onset of cytokeratin 10 expression, up-regulation of progesterone receptor expression, and loss of the cell cycle inhibitor, p27(Kip1) expression; none of these changes was observed after castration. Mice lacking functional estrogen receptor alpha failed to respond, demonstrating a requirement for estrogen receptor alpha in the epithelium and/or stroma to mediate the proliferative response to estrogen in the prostate gland.

  13. Effect of bisphosphonates on the mandibular bone and gingival epithelium of rats without tooth extraction

    PubMed Central

    DE PONTE, FRANCESCO SAVERIO; CATALFAMO, LUCIANO; MICALI, GREGORIO; RUNCI, MICHELE; CUTRONEO, GIUSEPPINA; VERMIGLIO, GIOVANNA; CENTOFANTI, ANTONIO; RIZZO, GIUSEPPINA

    2016-01-01

    Osteonecrosis of the jaw (ONJ) is an adverse effect of bisphosphonate treatment that has become the subject of increasing investigations, in particular due to its poorly understood pathogenesis. Several experimental studies on animal models have been conducted; however, the majority of these replicate human ONJ following tooth extraction, and describe alterations in the bone and gingival epithelium when necrosis is manifested. The aim of the present study was to analyze the rat mandibular bone and gingival epithelium during 45 days of zoledronate treatment (which is a bisphosphonate agent), without tooth extraction. Intraperitoneal injections of zoledronate acid (0.1 mg/kg) were performed three times a week in normal male Wistar rats (n=20), while a control group of rats (n=20) was treated with saline solution for 45 days. After 7, 15, 30 and 45 days of drug treatment, all rats were sacrificed and hematoxilin and eosin staining, immunofluorescence and scanning electron microscopy analyses were performed. The results of the analyses after 7 and 15 days of treatment were similar in the treatment and control group. After 30 and 45 days of treatment, structural alterations were observed in the bone. No structural alterations to the gingival epithelium were observed. Based on these results, it was hypothesized that low doses of zoledronate act directly on the bone tissues to induce morphological alterations from bone to necrotic tissue following surgical procedures, although no cytotoxic effects were detected in the gingival epithelium. PMID:27168789

  14. Histology, Immunohistochemistry and Ultrastructure of the Bovine Palatine Tonsil with Special Emphasis on Reticular Epithelium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The paired palatine tonsils are located at the junction of the nasopharynx and oropharynx; ideally positioned to sample antigens entering through either the nasal cavity or oral cavity. Entering antigens will first contact tonsilar epithelium. To better understand the cellular and functional composi...

  15. Quantification of transcriptome responses of the rumen epithelium to butyrate infusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Short-chain fatty acids (SCFAs), such as butyrate, produced by gut microorganisms play an important role in energy metabolism and physiology in ruminants as well as in human health. Butyrate is a preferred substrate in the rumen epithelium where approximately 90% of butyrate is metabolized. Additi...

  16. Apico-basal forces exerted by apoptotic cells drive epithelium folding.

    PubMed

    Monier, Bruno; Gettings, Melanie; Gay, Guillaume; Mangeat, Thomas; Schott, Sonia; Guarner, Ana; Suzanne, Magali

    2015-02-12

    Epithelium folding is a basic morphogenetic event that is essential in transforming simple two-dimensional epithelial sheets into three-dimensional structures in both vertebrates and invertebrates. Folding has been shown to rely on apical constriction. The resulting cell-shape changes depend either on adherens junction basal shift or on a redistribution of myosin II, which could be driven by mechanical signals. Yet the initial cellular mechanisms that trigger and coordinate cell remodelling remain largely unknown. Here we unravel the active role of apoptotic cells in initiating morphogenesis, thus revealing a novel mechanism of epithelium folding. We show that, in a live developing tissue, apoptotic cells exert a transient pulling force upon the apical surface of the epithelium through a highly dynamic apico-basal myosin II cable. The apoptotic cells then induce a non-autonomous increase in tissue tension together with cortical myosin II apical stabilization in the surrounding tissue, eventually resulting in epithelium folding. Together our results, supported by a theoretical biophysical three-dimensional model, identify an apoptotic myosin-II-dependent signal as the initial signal leading to cell reorganization and tissue folding. This work further reveals that, far from being passively eliminated as generally assumed (for example, during digit individualization), apoptotic cells actively influence their surroundings and trigger tissue remodelling through regulation of tissue tension.

  17. Xenogeneic acellular conjunctiva matrix as a scaffold of tissue-engineered corneal epithelium.

    PubMed

    Zhao, Haifeng; Qu, Mingli; Wang, Yao; Wang, Zhenyu; Shi, Weiyun

    2014-01-01

    Amniotic membrane-based tissue-engineered corneal epithelium has been widely used in the reconstruction of the ocular surface. However, it often degrades too early to ensure the success of the transplanted corneal epithelium when treating patients with severe ocular surface disorders. In the present study, we investigated the preparation of xenogeneic acellular conjunctiva matrix (aCM) and evaluated its efficacy and safety as a scaffold of tissue-engineered corneal epithelium. Native porcine conjunctiva was decellularized with 0.1% sodium dodecyl sulfate (SDS) for 12 h at 37°C and sterilized via γ-irradiation. Compared with native conjunctiva, more than 92% of the DNA was removed, and more than 90% of the extracellular matrix components (glycosaminoglycan and collagen) remained after the decellularization treatment. Compared with denuded amniotic membrane (dAM), the aCM possessed favorable optical transmittance, tensile strength, stability and biocompatibility as well as stronger resistance to degradation both in vitro and in vivo. The corneal epithelial cells seeded on aCM formed a multilayered epithelial structure and endured longer than did those on dAM. The aCM-based tissue-engineered corneal epithelium was more effective in the reconstruction of the ocular surface in rabbits with limbal stem cell deficiency. These findings support the application of xenogeneic acellular conjunctiva matrix as a scaffold for reconstructing the ocular surface.

  18. Biosynthesis of 11-cis-retinoids and retinyl esters by bovine pigment epithelium membranes

    SciTech Connect

    Fulton, B.S.; Rando, R.R.

    1987-12-01

    Previously, we have shown that retina/pigment epithelium membranes from the amphibian can synthesize 11-cis-retinoids from added all-trans-retinol. The activity was largely localized to the pigment epithelium. Here it is shown that, in the bovine system, the activity resides exclusively in the membranes of the pigment epithelium. Subcellular fractionation does not reveal a particular organelle where the activity resides. Washed bovine pigment epithelium membranes, which are devoid of retinoid redox activity, convert added all-trans-retinol to a mixture of 11-cis-retinol and its palmitate ester. all-trans-Retinal and all-trans-retinyl palmitate are not converted into 11-cis-retinoids by the membranes. The membranes show substantial ester synthetase activity, producing large amounts of all-trans-retinyl palmitate. Diverse chemical reagents, such as ethanol, hydroxylamine, and p-(hydroxymercuri)benzoate, inhibit both ester synthetase and isomerase activities in a roughly parallel fashion, suggesting a possible functional linkage between the two activities.

  19. Regeneration of the uterine epithelium in later stages of pseudopregnancy in the rabbit. An ultrastructural study.

    PubMed

    Busch, L C; Winterhager, E; Fischer, B

    1986-01-01

    Morphological changes of the uterine epithelium in later stages of pseudopregnancy in the rabbit have been studied using different morphological methods. The highly proliferated mucosa with numerous symplasms of a pseudopregnant animal returns to the morphology of a nonpregnant animal by apoptosis, moderate necrosis and lytic transformation of symplasms back to typical endometrial cells without desquamation of cells. The first signs of lytic transformation are observed on Day 8 of pseudopregnancy. Enhanced regeneration with apoptosis and lysis of the symplasmic nuclei is observed between Day 14 and Day 16. Full restoration of the epithelium with reappearance of ciliated cells, typical columnar and partly mucified epithelial cells is not completed earlier than Day 24 p. hCG. This epithelium, however, differs clearly from the epithelium of a virgin rabbit due to several residues of epithelial transformation. Thus, from a morphological point of view, pseudopregnancy in the rabbit lasts up to or even longer than Day 28 p. hCG with persisting ultrastructural remnants of the preceding cycle.

  20. [Ciliary epithelium and topical decongestants: how to minimize the undesirable events?].

    PubMed

    Laberko, E L; Zlobina, N V; Radtsig, E Yu; Bogomil'sky, M R

    2014-01-01

    The objective of the present study was to evaluate the influence of the combination of 0.1% xylometazoline with seawater (Rinomaris, "Jadran", Croatia) on the state and functional activity of the ciliary epithelium of the nasal cavity. The results of the study confirm the safety of this treatment and the possibility of its application in routine clinical practice. PMID:25588494

  1. An endocannabinoid system is present in the mouse olfactory epithelium but does not modulate olfaction.

    PubMed

    Hutch, C R; Hillard, C J; Jia, C; Hegg, C C

    2015-08-01

    Endocannabinoids modulate a diverse array of functions including progenitor cell proliferation in the central nervous system, and odorant detection and food intake in the mammalian central olfactory system and larval Xenopus laevis peripheral olfactory system. However, the presence and role of endocannabinoids in the peripheral olfactory epithelium have not been examined in mammals. We found the presence of cannabinoid type 1 (CB1) and cannabinoid type 2 (CB2) receptor protein and mRNA in the olfactory epithelium. Using either immunohistochemistry or calcium imaging we localized CB1 receptors on neurons, glia-like sustentacular cells, microvillous cells and progenitor-like basal cells. To examine the role of endocannabinoids, CB1- and CB2- receptor-deficient (CB1(-/-)/CB2(-/-)) mice were used. The endocannabinoid 2-arachidonylglycerol (2-AG) was present at high levels in both C57BL/6 wildtype and CB1(-/-)/CB2(-/-) mice. 2-AG synthetic and degradative enzymes are expressed in wildtype mice. A small but significant decrease in basal cell and olfactory sensory neuron numbers was observed in CB1(-/-)/CB2(-/-) mice compared to wildtype mice. The decrease in olfactory sensory neurons did not translate to impairment in olfactory-mediated behaviors assessed by the buried food test and habituation/dishabituation test. Collectively, these data indicate the presence of an endocannabinoid system in the mouse olfactory epithelium. However, unlike in tadpoles, endocannabinoids do not modulate olfaction. Further investigation on the role of endocannabinoids in progenitor cell function in the olfactory epithelium is warranted. PMID:26037800

  2. Notch regulation of progenitor cell behavior in quiescent and regenerating auditory epithelium of mature birds

    PubMed Central

    Daudet, Nicolas; Gibson, Robin; Shang, Jialin; Bernard, Amy; Lewis, Julian; Stone, Jennifer

    2009-01-01

    Unlike mammals, birds regenerate auditory hair cells (HCs) after injury. During regeneration, mature non-sensory supporting cells (SCs) leave quiescence and convert into HCs, through non-mitotic or mitotic mechanisms. During embryogenesis, Notch ligands from nascent HCs exert lateral inhibition, restricting HC production. Here, we examined whether Notch signalling (1) is needed in mature birds to maintain the HC/SC pattern in the undamaged auditory epithelium or (2) governs SC behavior once HCs are injured. We show that Notch pathway genes are transcribed in the mature undamaged epithelium, and after HC injury, their transcription is upregulated in the region of highest mitotic activity. In vitro treatment with DAPT, an inhibitor of Notch activity, had no effect on SCs in the undamaged epithelium. Following HC damage, DAPT had no direct effect on SC division. However, after damage, DAPT caused excessive regeneration of HCs at the expense of SCs, through both mitotic and non-mitotic mechanisms. Conversely, overexpression of activated Notch in SCs after damage caused them to maintain their phenotype and inhibited HC regeneration. Therefore, signalling through Notch is not required for SC quiescence in the healthy epithelium or to initiate HC regeneration after damage. Rather, Notch prevents SCs from regenerating excessive HCs after damage. PMID:19013445

  3. [Regulatory elements in the skin epithelium of Saccoglossus mereschkowskii (Enteropneusta, Hemichordata): electron microscopic and immunocytochemical study].

    PubMed

    Stoliarova, M V; Val'kovich, E I

    2013-01-01

    The aim of this investigation was to demonstrate the regulatory elements in the skin epithelium of Enteropneusta which are supposed to be related to the chordate ancestors. Using electron microscopy, it was found that in the skin epithelium of a representative of enteropneusts Saccoglossus mereschkowskii, the basal parts of some epitheliocytes took part in formation of a nerve layer. These cells were considered as receptor ciliated cells. The granular epithelial cells were shown to release secretion according to both exocrine and endocrine mechanism; these cells were characterized as endocrine-like regulatory cells. Fine granular cells possibly represent special receptor-endocrine-like cell type. The immunocytochemical detection of FMRFamid neuropeptide localization in histological sections confirmed the electron microscopic data on the presence of receptor and endocrine-like cells in the epithelium. It is suggested that the skin epithelium of Enteropneusta contains a peculiar neuro-endocrine regulatory system that is represented by receptor cells, receptor-endocrine-like cells of an open type and nerve elements of the nerve layer.

  4. Brain-derived neurotrophic factor (BDNF) expression in normal and regenerating olfactory epithelium of Xenopus laevis.

    PubMed

    Frontera, Jimena Laura; Cervino, Ailen Soledad; Jungblut, Lucas David; Paz, Dante Agustín

    2015-03-01

    Olfactory epithelium has the capability to continuously regenerate olfactory receptor neurons throughout life. Adult neurogenesis results from proliferation and differentiation of neural stem cells, and consequently, olfactory neuroepithelium offers an excellent opportunity to study neural regeneration and the factors involved in the maintenance and regeneration of all their cell types. We analyzed the expression of BDNF in the olfactory system under normal physiological conditions as well as during a massive regeneration induced by chemical destruction of the olfactory epithelium in Xenopus laevis larvae. We described the expression and presence of BDNF in the olfactory epithelium and bulb. In normal physiological conditions, sustentacular (glial) cells and a few scattered basal (stem) cells express BDNF in the olfactory epithelium as well as the granular cells in the olfactory bulb. Moreover, during massive regeneration, we demonstrated a drastic increase in basal cells expressing BDNF as well as an increase in BDNF in the olfactory bulb and nerve. Together these results suggest an important role of BDNF in the maintenance and regeneration of the olfactory system.

  5. Cycle and duration of the seminiferous epithelium in puma (Puma concolor).

    PubMed

    Leite, Flaviana Lima Guião; de Paula, Tarcízio Antônio Rego; da Matta, Sérgio Luis Pinto; Fonseca, Cláudio Cesar; das Neves, Marco Túlio David; de Barros, João Bosco Gonçalves

    2006-02-01

    Puma or sussuarana (Puma concolor) is the second largest feline in the American continent and has an ample latitudinal distribution in very diverse habitats. In relation to its conservation status, the puma is considered an extinction-threatened species. The study of the testis morphology and the spermatogenic process in a species is fundamental for establishing the physiologic patterns that will make possible the selection of the protocols for assisted reproduction. A number of peculiarities associated with the reproductive biology of specific species such as the duration of spermatogenic process can be used to determine the frequency of sperm collection. Nine adult male pumas maintained in captivity were used to determine the relative frequency of stages in the seminiferous epithelium cycle. Three of them received intra-testicular injections of 0.1ml tritiated thymidine to determine the duration of the seminiferous epithelium cycle, and were subjected to biopsy 7 days later. The cycle of the seminiferous epithelium in puma was didactically described into eight stages by the tubular morphology method. The total duration of one seminiferous epithelium cycle in puma was calculated to be 9.89 days, and approximately 44.5 days are required for development of spermatozoon from spermatogonia. The duration of spermiogenesis, prophase and other events of meiosis were 14.08, 15.20 and 1.79 days, respectively. The relative frequency of the pre-meiotic, meiotic and post-meiotic phases were 3.98, 1.79 and 4.12 days, respectively.

  6. Loss of Retinal Function and Pigment Epithelium Changes in a Patient with Common Variable Immunodeficiency

    PubMed Central

    Halborg, Jakob; Sørensen, Torben L.

    2012-01-01

    Common variable immunodeficiency (CVID) has only scarcely been associated with ocular symptoms and rarely with retinal disease. In this case we describe a patient with distinct morphological and functional alterations in the retina. The patient presents with characteristic changes in retinal pigment epithelium, autofluorescence, and electrophysiology. PMID:23056974

  7. In vitro absorption of gamma-globulin by neonatal intestinal epithelium of the pig.

    PubMed

    Lecce, J G

    1966-06-01

    1. An in vitro method, using fluorescent gamma-globulin and everted neonatal pig's intestinal slices, for the study of the active transport of large molecules is described.2. Uptake of gamma-globulin occurred within 15 min and required no exogenous substrates.3. In vitro absorption of gamma-globulin by intestinal epithelium was limited to the neonatal pig and 5-day-old mouse. No uptake was seen in intestines from a mature mouse, a pig with diarrhoea, a normal pig, a mature rabbit, a guinea-pig, a chick, and a chick embryo. Chick embryo yolk sac readily took up gamma-globulin.4. Rings of everted intestinal epithelium remained active (still absorbed gamma-globulin) after incubating for 4-6 hr in balanced salt solution (BSS).5. Uptake of gamma-globulin required oxygen and sodium and was reversibly inhibited by metabolic antagonists such as iodoacetate, arsenate, fluoride, 4,6-dinitro-varphi-cresol, phlorrhizin, anaerobiosis and cold. Under the conditions of the test, large colloidal molecules did not inhibit uptake of gamma-globulin.6. Similar results (although not as clear-cut) with metabolic inhibitors were obtained with preparations of chick embryo yolk sacs.7. Injuring mature pig's intestinal epithelium with surface-active agents did not produce non-specific absorption artifacts that resembled the specific absorption found in immature pig's intestinal epithelium.

  8. Ultrastructural observations on experimentally produced melanin pigmentation of the corneal epithelium.

    PubMed Central

    McCracken, J. S.; Klintworth, G. K.

    1976-01-01

    Melanin pigmentation of the corneal epithelium was induced in pigmented guinea pigs by the topical application of colchicine to their eyes or by corneal cauterization with silver nitrate. With colchicine the pigmentation was preceded by the development of an abnormal corneal epithelium in which numerous cells became arrested in cell division. The corneal melanosis resulted largely from the migration of melanocytes into the corneal epithelium from the normally pigmented contiguous conjunctiva and to a lesser extent from the presence of melanin granules within corneal epithelial cells. In both models a leukocytic and vascular invasion of the cornea proceded and accompanied the migration of melanocytes into the corneal epithelium. Electron microscopy disclosed cells with the same morphology as conjunctival melanocytes between the epithelial cells of the cornea. Mature melanin granules were also present within some squamous epithelial cells as individual granules or as clusters. The ultrastructural findings are viewed in relation to how melanin granules are transferred from melanocytes to epithelial cells. Evidence is presented which suggests that malanin granule transfer may follow the fusion of the membranes of the melanocytes and epithelial cells. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 PMID:970438

  9. Cavitary lung cancer lined with normal bronchial epithelium and cancer cells.

    PubMed

    Goto, Taichiro; Maeshima, Arafumi; Oyamada, Yoshitaka; Kato, Ryoichi

    2011-01-01

    Reports of cavitary lung cancer are not uncommon, and the cavity generally contains either dilated bronchi or cancer cells. Recently, we encountered a surgical case of cavitary lung cancer whose cavity tended to enlarge during long-term follow-up, and was found to be lined with normal bronchial epithelium and adenocarcinoma cells. PMID:21980325

  10. Comparison of the effects of different menstrual tampons on the vaginal epithelium: a randomised clinical trial.

    PubMed

    Raudrant, D; Landrivon, G; Frappart, L; De Haas, P; Champion, F; Ecochard, R

    1995-01-01

    The effects on the vaginal epithelium of three different menstrual tampons in normal conditions of use were studied in 41 women during the menstrual period. The vaginal epithelium was studied in a total of 123 cycles at a structural and ultra-structural level with colposcopy, vaginal smear and biopsy on TEM and SEM. One of the three tampons studied showed a lower level of abnormalities on colposcopy (36.6% vs. 56.1% vs. 68.3%), with an inverse correlation between the severity of the dryness and the quantity of blood absorbed by the tampon (4.2 g when the colposcopy was normal vs. 1.8 g in case of severe dryness). Cytology is not a good test for assessing the effects of tampons because of the high rate of acellular and uninterpretable samplings. The biopsy effects were defined according to their depth in the epithelium. The same tampon showed the lowest level in biopsy abnormalities. No correlation was found between severity of the colposcopy and biopsy results. Colposcopy can demonstrate the degree of severity of dryness or any other effect, but biopsy only confirms the effect and does not correlate the degree of severity. Materials and designs of tampons can play a role in reducing the drying effects to the vaginal epithelium.

  11. An endocannabinoid system is present in the mouse olfactory epithelium but does not modulate olfaction.

    PubMed

    Hutch, C R; Hillard, C J; Jia, C; Hegg, C C

    2015-08-01

    Endocannabinoids modulate a diverse array of functions including progenitor cell proliferation in the central nervous system, and odorant detection and food intake in the mammalian central olfactory system and larval Xenopus laevis peripheral olfactory system. However, the presence and role of endocannabinoids in the peripheral olfactory epithelium have not been examined in mammals. We found the presence of cannabinoid type 1 (CB1) and cannabinoid type 2 (CB2) receptor protein and mRNA in the olfactory epithelium. Using either immunohistochemistry or calcium imaging we localized CB1 receptors on neurons, glia-like sustentacular cells, microvillous cells and progenitor-like basal cells. To examine the role of endocannabinoids, CB1- and CB2- receptor-deficient (CB1(-/-)/CB2(-/-)) mice were used. The endocannabinoid 2-arachidonylglycerol (2-AG) was present at high levels in both C57BL/6 wildtype and CB1(-/-)/CB2(-/-) mice. 2-AG synthetic and degradative enzymes are expressed in wildtype mice. A small but significant decrease in basal cell and olfactory sensory neuron numbers was observed in CB1(-/-)/CB2(-/-) mice compared to wildtype mice. The decrease in olfactory sensory neurons did not translate to impairment in olfactory-mediated behaviors assessed by the buried food test and habituation/dishabituation test. Collectively, these data indicate the presence of an endocannabinoid system in the mouse olfactory epithelium. However, unlike in tadpoles, endocannabinoids do not modulate olfaction. Further investigation on the role of endocannabinoids in progenitor cell function in the olfactory epithelium is warranted.

  12. FORMALDEHYDE-INDUCED GENE EXPRESSION IN F344 RAT NASAL RESPIRATORY EPITHELIUM.

    EPA Science Inventory

    Formaldehyde-induced gene expression in F344 rat nasal respiratory epithelium

    ABSTRACT

    Formaldehyde, an occupational and environmental toxicant used extensively in the manufacturing of many household and personal use products, is known to induce squamous cell carci...

  13. CD36 is expressed in a defined subpopulation of neurons in the olfactory epithelium

    PubMed Central

    Xavier, André Machado; Ludwig, Raissa Guimarães; Nagai, Maíra Harume; de Almeida, Tiago Jonas; Watanabe, Hebe Mizuno; Hirata, Marcio Yukio; Rosenstock, Tatiana Rosado; Papes, Fabio; Malnic, Bettina; Glezer, Isaias

    2016-01-01

    The sensory neurons in the olfactory epithelium (OSNs) are equipped with a large repertoire of olfactory receptors and the associated signal transduction machinery. In addition to the canonical OSNs, which express odorant receptors (ORs), the epithelium contains specialized subpopulations of sensory neurons that can detect specific information from environmental cues and relay it to relevant neuronal circuitries. Here we describe a subpopulation of mature OSNs in the main olfactory epithelium (MOE) which expresses CD36, a multifunctional receptor involved in a series of biological processes, including sensory perception of lipid ligands. The Cd36 expressing neurons coexpress markers of mature OSNs and are dispersed throughout the MOE. Unlike several ORs analyzed in our study, we found frequent coexpression of the OR Olfr287 in these neurons, suggesting that only a specific set of ORs may be coexpressed with CD36 in OSNs. We also show that CD36 is expressed in the cilia of OSNs, indicating a possible role in odorant detection. CD36-deficient mice display no signs of gross changes in the organization of the olfactory epithelium, but show impaired preference for a lipid mixture odor. Our results show that CD36-expressing neurons represent a distinct population of OSNs, which may have specific functions in olfaction. PMID:27145700

  14. Substance P and NK-1R expression in oral precancerous epithelium.

    PubMed

    Gonzalez-Moles, Miguel A; Brener, S; Ruiz-Avila, I; Gil-Montoya, J A; Tostes, D; Bravo, M; Esteban, F

    2009-12-01

    The objectives of this study were to investigate the presence and distribution of substance P and neurokinin 1 receptor in oral premalignant epithelium and their relation with the presence of dysplasia, and to analyze whether the expression of substance P can be considered an early oncogenic event in oral carcinogenesis. substance P and neurokinin 1 receptor expression was immunohistochemically studied in 83 oral carcinomas and adjacent non-tumor epithelia. The presence and degree of epithelial dysplasia was assessed according to WHO criteria. The nuclear, cytoplasmic, and membrane expression of substance P and the cytoplasmic and membrane expression of neurokinin 1 receptor were assessed in tumor and adjacent non-tumor epithelium. Nuclear and cytoplasmic expression of substance P in non-tumor epithelium was significantly associated with the presence of epithelial dysplasia (p<0.001) and carcinoma in situ (p=0.021). Nuclear, cytoplasmic, and membrane expressions of substance P in non-tumor epithelium were significantly (p<0.001) associated with its expression in the corresponding tumor. These findings suggest that substance P plays a role in early oral carcinogenesis by promoting the proliferation and growth of premalignant fields.

  15. A quantitative ultrastructural analysis of changes in hamster cheek-pouch epithelium treated with vitamin A.

    PubMed

    Hill, M W; Harris, R R; Carron, C P

    1982-01-01

    The ultrastructural changes induced by the topical application of retinol acetate on hamster cheek pouch epithelium were evaluated using stereological analysis. Electron micrographs were prepared of the basal and superficial regions of the nucleated cell layer of the epithelium obtained from 3 treated and 3 control animals and examined at two levels of magnification. A total of 528 micrographs were analyzed using a coherent double lattice test system. Although the mean thickness of the nucleated cell layer did not change significantly after 10 days of treatment with retinol acetate the formation of keratinized squames was completely inhibited. This was paralleled by significant changes in the volume density of a number of organelles in both the basal and superficial strata. Rough endoplasmic reticulum increased significantly whereas filaments, which maintained a constant diameter of approximately 9 nm, keratohyalin granules and membrane-coating granules decreased in both strata. Desmosomes also showed a significant decrease in numerical area density in the treated tissues. In contrast, no changes were observed in the volume density of the Golgi apparatus, free ribosomes or mitochondria in the treated epithelium. It is concluded that this treatment provides an epithelium lacking all features of keratinization and may be a useful model for examining metabolic activities specifically associated with keratinization.

  16. A quantitative electron microscopic analysis of the keratinizing epithelium of noral human hard palate.

    PubMed

    Meyer, M; Schroeder, H E

    1975-01-01

    The epithelium of normal human hard palate was subjected to sterologic analysis. Ten biosies were selected from a total of twenty specimens collected from 9 to 16 year old females, and processed for light- and electron microscopy. At two levels of magnification, electron micrographs were sampled from three strata (basale, spinosum, granulosum) in two locations (epithelial ridges and portions over connective tissue papillae). Stereologic point counting procedures were employed to analyse a total 1560 electron micrographs. In general, the thickness of the palate epithelium was 0.12 mm (over papillae) and 0.31 mm (in ridges), the epithelium is distinctly stratified, and homogeneously ortho-keratinized. From basal to granular layers, the composition of strata revealed decreasing densities of nuclei, mitochondria, membrane-bound organelles and aggregates of free ribosomes. Keratohyalin bodies and membrane coating granules increased, and cytoplasmic filaments with a constant diameter of about 85 A increased from 14 to 30% of cytoplasmic unit volume. The cytoplasmic ground substance occupied a stable 50% of the epithelial cytoplasm in all strata. The composition of basal layers in ridges differed from that over connective tissue papillae. The data are discussed in relation to the observations that (1) an increasing gradient of filament density is not the most characteristic feature of ortho-keratinizing oral epithelium and (2) differences in the degree of differentiation in cells of the stratum basale coincided with the comparable frequency distribution pattern of dividing cells.

  17. A light, transmission and scanning electron microscope study of snuff-treated hamster cheek pouch epithelium.

    PubMed

    Ashrafi, S H; Das, A; Worowongvasu, R; Mehdinejad, B; Waterhouse, J P

    1992-03-01

    The effects of smokeless tobacco (snuff) on hamster cheek mucosa were studied by light microscopy, transmission (TEM) and scanning electron microscopy (SEM). Two grams of commercially available smokeless tobacco were placed into the blind end of the right cheek pouch of each experimental animal, once a day and five days a week for 24 months. The control animals did not receive smokeless tobacco. After 24 months treatment with smokeless tobacco, hamster cheek mucosal epithelium lost its translucency and had become whitish in color. By light microscopy hyperorthokeratosis, prominent granular cell layers with increased keratohyalin granules and hyperplasia were seen. At the ultrastructural level, wider intercellular spaces filled with microvilli, numerous shorter desmosomes, many thin tonofilament bundles, increased number of mitochondria, membrane coating granules and keratohyalin granules were seen in snuff-treated epithelium. The changes in the surface of the epithelium as seen by SEM were the development of an irregular arrangement of the microridges and the disappearance of the normal honeycomb pattern. The microridges were irregular, widened and surrounded the irregular elongated pits. Some smooth areas without microridges and pits were also seen. The long-term histological, TEM and SEM changes induced by smokeless tobacco treatment of the epithelium are well correlated with each other and were similar to those reported in human leukoplakia without dyskeratosis. They imply changes of pathological response resulting from topically applied snuff.

  18. Digital histologic analysis reveals morphometric patterns of age-related involution in breast epithelium and stroma.

    PubMed

    Sandhu, Rupninder; Chollet-Hinton, Lynn; Kirk, Erin L; Midkiff, Bentley; Troester, Melissa A

    2016-02-01

    Complete age-related regression of mammary epithelium, often termed postmenopausal involution, is associated with decreased breast cancer risk. However, most studies have qualitatively assessed involution. We quantitatively analyzed epithelium, stroma, and adipose tissue from histologically normal breast tissue of 454 patients in the Normal Breast Study. High-resolution digital images of normal breast hematoxylin and eosin-stained slides were partitioned into epithelium, adipose tissue, and nonfatty stroma. Percentage area and nuclei per unit area (nuclear density) were calculated for each component. Quantitative data were evaluated in association with age using linear regression and cubic spline models. Stromal area decreased (P = 0.0002), and adipose tissue area increased (P < 0.0001), with an approximate 0.7% change in area for each component, until age 55 years when these area measures reached a steady state. Although epithelial area did not show linear changes with age, epithelial nuclear density decreased linearly beginning in the third decade of life. No significant age-related trends were observed for stromal or adipose nuclear density. Digital image analysis offers a high-throughput method for quantitatively measuring tissue morphometry and for objectively assessing age-related changes in adipose tissue, stroma, and epithelium. Epithelial nuclear density is a quantitative measure of age-related breast involution that begins to decline in the early premenopausal period.

  19. Public perceptions of hurricane modification.

    PubMed

    Klima, Kelly; Bruine de Bruin, Wändi; Morgan, M Granger; Grossmann, Iris

    2012-07-01

    If hurricane modification were to become a feasible strategy for potentially reducing hurricane damages, it would likely generate public discourse about whether to support its implementation. To facilitate an informed and constructive discourse, policymakers need to understand how people perceive hurricane modification. Here, we examine Florida residents' perceptions of hurricane modification techniques that aim to alter path and wind speed. Following the mental models approach, we conducted a survey study about public perceptions of hurricane modification that was guided by formative interviews on the topic. We report a set of four primary findings. First, hurricane modification was perceived as a relatively ineffective strategy for damage reduction, compared to other strategies for damage reduction. Second, hurricane modification was expected to lead to changes in projected hurricane path, but not necessarily to the successful reduction of projected hurricane strength. Third, more anger was evoked when a hurricane was described as having changed from the initially forecasted path or strength after an attempted modification. Fourth, unlike what we expected, participants who more strongly agreed with statements that recognized the uncertainty inherent in forecasts reported more rather than less anger at scientists across hurricane modification scenarios. If the efficacy of intensity-reduction techniques can be increased, people may be willing to support hurricane modification. However, such an effort would need to be combined with open and honest communications to members of the general public.

  20. Induction and Antagonism of Antiviral Responses in Respiratory Syncytial Virus-Infected Pediatric Airway Epithelium

    PubMed Central

    Villenave, Rémi; Broadbent, Lindsay; Douglas, Isobel; Lyons, Jeremy D.; Coyle, Peter V.; Teng, Michael N.; Tripp, Ralph A.; Heaney, Liam G.; Shields, Michael D.

    2015-01-01

    ABSTRACT Airway epithelium is the primary target of many respiratory viruses. However, virus induction and antagonism of host responses by human airway epithelium remains poorly understood. To address this, we developed a model of respiratory syncytial virus (RSV) infection based on well-differentiated pediatric primary bronchial epithelial cell cultures (WD-PBECs) that mimics hallmarks of RSV disease in infants. RSV is the most important respiratory viral pathogen in young infants worldwide. We found that RSV induces a potent antiviral state in WD-PBECs that was mediated in part by secreted factors, including interferon lambda 1 (IFN-λ1)/interleukin-29 (IL-29). In contrast, type I IFNs were not detected following RSV infection of WD-PBECs. IFN responses in RSV-infected WD-PBECs reflected those in lower airway samples from RSV-hospitalized infants. In view of the prominence of IL-29, we determined whether recombinant IL-29 treatment of WD-PBECs before or after infection abrogated RSV replication. Interestingly, IL-29 demonstrated prophylactic, but not therapeutic, potential against RSV. The absence of therapeutic potential reflected effective RSV antagonism of IFN-mediated antiviral responses in infected cells. Our data are consistent with RSV nonstructural proteins 1 and/or 2 perturbing the Jak-STAT signaling pathway, with concomitant reduced expression of antiviral effector molecules, such as MxA/B. Antagonism of Jak-STAT signaling was restricted to RSV-infected cells in WD-PBEC cultures. Importantly, our study provides the rationale to further explore IL-29 as a novel RSV prophylactic. IMPORTANCE Most respiratory viruses target airway epithelium for infection and replication, which is central to causing disease. However, for most human viruses we have a poor understanding of their interactions with human airway epithelium. Respiratory syncytial virus (RSV) is the most important viral pathogen of young infants. To help understand RSV interactions with pediatric

  1. Transcriptional responses in the rat nasal epithelium following subchronic inhalation of naphthalene vapor.

    PubMed

    Clewell, H J; Efremenko, A; Campbell, J L; Dodd, D E; Thomas, R S

    2014-10-01

    Male and female Fischer 344 rats were exposed to naphthalene vapors at 0 (controls), 0.1, 1, 10, and 30ppm for 6h/d, 5 d/wk, over a 90-day period. Following exposure, the respiratory epithelium and olfactory epithelium from the nasal cavity were dissected separately, RNA was isolated, and gene expression microarray analysis was conducted. Only a few significant gene expression changes were observed in the olfactory or respiratory epithelium of either gender at the lowest concentration (0.1ppm). At the 1.0ppm concentration there was limited evidence of an oxidative stress response in the respiratory epithelium, but not in the olfactory epithelium. In contrast, a large number of significantly enriched cellular pathway responses were observed in both tissues at the two highest concentrations (10 and 30ppm, which correspond to tumorigenic concentrations in the NTP bioassay). The nature of these responses supports a mode of action involving oxidative stress, inflammation and proliferation. These results are consistent with a dose-dependent transition in the mode of action for naphthalene toxicity/carcinogenicity between 1.0 and 10ppm in the rat. In the female olfactory epithelium (the gender/site with the highest incidences of neuroblastomas in the NTP bioassay), the lowest concentration at which any signaling pathway was significantly affected, as characterized by the median pathway benchmark dose (BMD) or its 95% lower bound (BMDL) was 6.0 or 3.7ppm, respectively, while the lowest female olfactory BMD values for pathways related to glutathione homeostasis, inflammation, and proliferation were 16.1, 11.1, and 8.4ppm, respectively. In the male respiratory epithelium (the gender/site with the highest incidences of adenomas in the NTP bioassay), the lowest pathway BMD and BMDL were 0.4 and 0.3ppm, respectively, and the lowest male respiratory BMD values for pathways related to glutathione homeostasis, inflammation, and proliferation were 0.5, 0.7, and 0.9ppm, respectively

  2. Increase in immune cell infiltration with progression of oral epithelium from hyperkeratosis to dysplasia and carcinoma

    PubMed Central

    Gannot, G; Gannot, I; Vered, H; Buchner, A; Keisari, Y

    2002-01-01

    In the present study, epithelium derived lesions of various pathological manifestations were examined histologically and immunohistochemically for mononuclear cell infiltration. The infiltrate under the transformed epithelium of oral lesions, was examined for differences in the composition of immune mononuclear cells as the epithelium moves from hyperkeratosis through various degrees of dysplasia to squamous cell carcinoma. The study was performed on 53 human tongue tissues diagnosed as hyperkeratosis (11 cases), mild dysplasia (nine cases), moderate and severe dysplasia (14 cases) and squamous cell carcinoma (19 cases). A similar analysis was performed on 30 parotid gland tissues diagnosed as pleomorphic adenoma (14 cases) and carcinoma ex-pleomorphic adenoma (16 cases). Immunohistochemical analysis of various surface markers of the tumour infiltrating immune cells was performed and correlated with the transformation level as defined by morphology and the expression of p53 in the epithelium. The results revealed that, in the tongue lesions, the changes in the epithelium from normal appearance to transformed were accompanied by a corresponding increase in the infiltration of CD4, CD8, CD14, CD19+20, and HLA/DR positive cells. The most significant change was an increase in B lymphocytes in tongue lesions, that was in accordance with the transformation level (P<0.001). In the salivary gland, a significant number of cases did not show an infiltrate. In cases where an infiltrate was present, a similar pattern was observed and the more malignant tissues exhibited a higher degree of immune cell infiltration. British Journal of Cancer (2002) 86, 1444–1448. DOI: 10.1038/sj/bjc/6600282 www.bjcancer.com © 2002 Cancer Research UK PMID:11986779

  3. FELINE TRITRICHOMONAS FOETUS ADHERE TO INTESTINAL EPITHELIUM BY RECEPTOR-LIGAND-DEPENDENT MECHANISMS

    PubMed Central

    Tolbert, M.K.; Stauffer, S.H.; Gookin, J.L.

    2013-01-01

    Tritrichomonas foetus (TF) is a protozoan that infects the feline ileum and colon resulting in chronic diarrhea. Up to 30% of young purebred cats are infected with TF and the infection is recognized as pandemic. Only a single drug, characterized by a narrow margin of safety and emerging development of resistance, is effective for treatment. While the venereal pathogenicity of bovine TF is attributed to adherence to uterovaginal epithelium, the pathogenesis of diarrhea in feline TF infection is unknown. The aim of this study was to establish an in vitro model of feline TF adhesion to intestinal epithelium. Confluent monolayers of porcine intestinal epithelial cells (IPEC-J2) were infected with axenic cultures of feline TF that were labeled with [3H] thymidine or CFSE and harvested at log-phase. The effect of multiplicity and duration of infection, viability of TF, binding competition, formalin fixation and cytoskeletal inhibitors on adherence of feline TF to IPEC-J2 monolayers was quantified by liquid scintillation counting and immunofluorescence. [3H] thymidine and CFSE-labeled TF reproducibly adhered to IPEC-J2 monolayers. Clinical isolates of feline TF adhered to the intestinal epithelium in significantly greater numbers than Pentatrichomonas hominis, the latter of which is a presumably nonpathogenic trichomonad. Adhesion of TF required viable trophozoites but was independent of cytoskeletal activity. Based on saturation and competition binding experiments, adherence of feline TF to the epithelium occurred via specific receptor-ligand interactions. The developed model provides a valuable resource for assessing pathogenic mechanisms of feline TF and developing novel pharmacologic therapies for blocking the adhesion of feline TF to the intestinal epithelium. PMID:23182300

  4. Progressive effects of N-myc deficiency on proliferation, neurogenesis, and morphogenesis in the olfactory epithelium.

    PubMed

    Wittmann, Walter; Schimmang, Thomas; Gunhaga, Lena

    2014-06-01

    N-myc belongs to the myc proto-oncogene family, which is involved in numerous cellular processes such as proliferation, growth, apoptosis, and differentiation. Conditional deletion of N-myc in the mouse nervous system disrupted brain development, indicating that N-myc plays an essential role during neural development. How the development of the olfactory epithelium and neurogenesis within are affected by the loss of N-myc has, however, not been determined. To address these issues, we examined an N-myc(Foxg1Cre) conditional mouse line, in which N-myc is depleted in the olfactory epithelium. First changes in N-myc mutants were detected at E11.5, with reduced proliferation and neurogenesis in a slightly smaller olfactory epithelium. The phenotype was more pronounced at E13.5, with a complete lack of Hes5-positive progenitor cells, decreased proliferation, and neurogenesis. In addition, stereological analyses revealed reduced cell size of post-mitotic neurons in the olfactory epithelium, which contributed to a smaller olfactory pit. Furthermore, we observed diminished proliferation and neurogenesis also in the vomeronasal organ, which likewise was reduced in size. In addition, the generation of gonadotropin-releasing hormone neurons was severely reduced in N-myc mutants. Thus, diminished neurogenesis and proliferation in combination with smaller neurons might explain the morphological defects in the N-myc depleted olfactory structures. Moreover, our results suggest an important role for N-myc in regulating ongoing neurogenesis, in part by maintaining the Hes5-positive progenitor pool. In summary, our results provide evidence that N-myc deficiency in the olfactory epithelium progressively diminishes proliferation and neurogenesis with negative consequences at structural and cellular levels.

  5. Cux2 acts as a critical regulator for neurogenesis in the olfactory epithelium of vertebrates.

    PubMed

    Wittmann, Walter; Iulianella, Angelo; Gunhaga, Lena

    2014-04-01

    Signaling pathways and transcription factors are crucial regulators of vertebrate neurogenesis, exerting their function in a spatial and temporal manner. Despite recent advances in our understanding of the molecular regulation of embryonic neurogenesis, little is known regarding how different signaling pathways interact to tightly regulate this process during the development of neuroepithelia. To address this, we have investigated the events lying upstream and downstream of a key neurogenic factor, the Cut-like homeodomain transcription factor-2 (Cux2), during embryonic neurogenesis in chick and mouse. By using the olfactory epithelium as a model for neurogenesis we have analyzed mouse embryos deficient in Cux2, as well as chick embryos exposed to Cux2 silencing (si) RNA or a Cux2 over-expression construct. We provide evidence that enhanced BMP activity increases Cux2 expression and suppresses olfactory neurogenesis in the chick olfactory epithelium. In addition, our results show that up-regulation of Cux2, either BMP-induced or ectopically over-expressed, reduce Delta1 expression and suppress proliferation. Interestingly, the loss of Cux2 activity, using mutant mice or siRNA in chick, also diminishes neurogenesis, Notch activity and cell proliferation in the olfactory epithelium. Our results suggest that controlled low levels of Cux2 activity are necessary for proper Notch signaling, maintenance of the proliferative pool and ongoing neurogenesis in the olfactory epithelium. Thus, we demonstrate a novel conserved mechanism in vertebrates in which levels of Cux2 activity play an important role for ongoing neurogenesis in the olfactory epithelium.

  6. Morphological Alterations of the Palpebral Conjunctival Epithelium in a Dry Eye Model

    PubMed Central

    Henriksson, Johanna Tukler; De Paiva, Cintia S.; Farley, William; Pflugfelder, Stephen C.; Burns, Alan R.; Bergmanson, Jan P.G.

    2012-01-01

    Purpose To investigate the normal palpebral conjunctival histology in C57BL/6 mice, and the structural changes that occur in a dry eye model. Methods 24 male and female C57BL/6 mice, 8 untreated (UT) and 16 exposed to experimental ocular surface desiccating stress (DS). Ocular dryness was induced by administration of scopolamine hydrobromide (0.5 mg/0.2 ml) QID for 5 (DS5) or 10 (DS10) days. Counts and measurements were obtained using anatomical reference points and goblet cell density was investigated with a variety of stains. Results Near the junction between the lid margin and the normal palpebral conjunctiva, the epithelium had an average thickness of 45.6±10.5μm, 8.8±2.0 cell layers, versus 37.7±5.6μm, 7.4±1.3 layers in DS10 (P<0.05). In the goblet cell populated palpebral region the normal epithelium was thicker (P<0.05) than in DS5 and DS10. In the control, 43% of the goblet cells were covered by squamous epithelium, compared to 58% (DS5) and 63% (DS10) (P<0.05). A decreased number of Periodic Acid Schiff (PAS) and Alcian blue stained goblet cells was observed in the dry eye. Not all goblet cells stained with PAS and Alcian blue. Conclusions The mouse palpebral conjunctival epithelium was structurally similar to the human. After DS the palpebral conjunctival epithelium decreased in thickness and goblet cell access to the surface appeared to be inhibited by surrounding epithelial cells, potentially slowing down their migration to the surface. Differential staining with PAS and Alcian blue suggests there may be different subtypes of conjunctival goblet cells. PMID:23146932

  7. Effect of the Synthetic NC-1059 Peptide on Diffusion of Riboflavin across an Intact Corneal Epithelium

    PubMed Central

    Zhang, Yuntao; Sukthankar, Pinakin; Tomich, John M.; Conrad, Gary W.

    2012-01-01

    Purpose. To investigate the effect of the peptide NC-1059 on riboflavin (RF) diffusion across an intact corneal epithelium into the stroma. Methods. NC-1059 peptide was synthesized by solid-phase synthesis with 9-fluorenylmethoxycarbonyl chemistry, characterized by reversed-phase HPLC, and matrix-assisted laser desorption ionization time-of-flight mass spectroscopy. The diffusion of RF across embryonic day 18 chick corneal epithelium ex vivo was monitored using confocal microscopy. The depth distributions of RF in the corneal stroma were calculated using a group of linear equations based on the relationship between RF fluorescence intensity and concentration. Results. Data presented in this study demonstrate that the NC-1059 peptide can transiently open the intact epithelial barrier to allow the permeation of RF into the stroma. The effect of NC-1059 peptide on RF diffusion across the corneal epithelium was concentration and time dependent. The amount of RF reaching a 50-μm depth of chick corneal stoma increased dramatically after exposure to NC-1059 for 10 minutes, reaching a plateau by 30 minutes. The concentrations of RF in the presence of NC-1059 at corneal stromal depths of 50, 100, and 150 μm were significantly higher than in the absence of the peptide, and almost as high as in corneas in which the epithelium first had been physically removed. In addition, a cell viability assay indicated that the NC-1059 peptide did not kill corneal epithelial cells. Conclusions. NC-1059 peptide significantly enhances the diffusion of RF across intact corneal epithelium into the stroma. PMID:22447859

  8. WNT7A and PAX6 define corneal epithelium homeostasis and pathogenesis.

    PubMed

    Ouyang, Hong; Xue, Yuanchao; Lin, Ying; Zhang, Xiaohui; Xi, Lei; Patel, Sherrina; Cai, Huimin; Luo, Jing; Zhang, Meixia; Zhang, Ming; Yang, Yang; Li, Gen; Li, Hairi; Jiang, Wei; Yeh, Emily; Lin, Jonathan; Pei, Michelle; Zhu, Jin; Cao, Guiqun; Zhang, Liangfang; Yu, Benjamin; Chen, Shaochen; Fu, Xiang-Dong; Liu, Yizhi; Zhang, Kang

    2014-07-17

    The surface of the cornea consists of a unique type of non-keratinized epithelial cells arranged in an orderly fashion, and this is essential for vision by maintaining transparency for light transmission. Cornea epithelial cells (CECs) undergo continuous renewal from limbal stem or progenitor cells (LSCs), and deficiency in LSCs or corneal epithelium--which turns cornea into a non-transparent, keratinized skin-like epithelium--causes corneal surface disease that leads to blindness in millions of people worldwide. How LSCs are maintained and differentiated into corneal epithelium in healthy individuals and which key molecular events are defective in patients have been largely unknown. Here we report establishment of an in vitro feeder-cell-free LSC expansion and three-dimensional corneal differentiation protocol in which we found that the transcription factors p63 (tumour protein 63) and PAX6 (paired box protein PAX6) act together to specify LSCs, and WNT7A controls corneal epithelium differentiation through PAX6. Loss of WNT7A or PAX6 induces LSCs into skin-like epithelium, a critical defect tightly linked to common human corneal diseases. Notably, transduction of PAX6 in skin epithelial stem cells is sufficient to convert them to LSC-like cells, and upon transplantation onto eyes in a rabbit corneal injury model, these reprogrammed cells are able to replenish CECs and repair damaged corneal surface. These findings suggest a central role of the WNT7A-PAX6 axis in corneal epithelial cell fate determination, and point to a new strategy for treating corneal surface diseases.

  9. Conserved form and function of the germinal epithelium through 500 million years of vertebrate evolution.

    PubMed

    Grier, Harry J; Uribe, Mari Carmen; Lo Nostro, Fabiana L; Mims, Steven D; Parenti, Lynne R

    2016-08-01

    The germinal epithelium, i.e., the site of germ cell production in males and females, has maintained a constant form and function throughout 500 million years of vertebrate evolution. The distinguishing characteristic of germinal epithelia among all vertebrates, males, and females, is the presence of germ cells among somatic epithelial cells. The somatic epithelial cells, Sertoli cells in males or follicle (granulosa) cells in females, encompass and isolate germ cells. Morphology of all vertebrate germinal epithelia conforms to the standard definition of an epithelium: epithelial cells are interconnected, border a body surface or lumen, are avascular and are supported by a basement membrane. Variation in morphology of gonads, which develop from the germinal epithelium, is correlated with the evolution of reproductive modes. In hagfishes, lampreys, and elasmobranchs, the germinal epithelia of males produce spermatocysts. A major rearrangement of testis morphology diagnoses osteichthyans: the spermatocysts are arranged in tubules or lobules. In protogynous (female to male) sex reversal in teleost fishes, female germinal epithelial cells (prefollicle cells) and oogonia transform into the first male somatic cells (Sertoli cells) and spermatogonia in the developing testis lobules. This common origin of cell types from the germinal epithelium in fishes with protogynous sex reversal supports the homology of Sertoli cells and follicle cells. Spermatogenesis in amphibians develops within spermatocysts in testis lobules. In amniotes vertebrates, the testis is composed of seminiferous tubules wherein spermatogenesis occurs radially. Emerging research indicates that some mammals do not have lifetime determinate fecundity. The fact emerged that germinal epithelia occur in the gonads of all vertebrates examined herein of both sexes and has the same form and function across all vertebrate taxa. Continued study of the form and function of the germinal epithelium in vertebrates

  10. Conserved form and function of the germinal epithelium through 500 million years of vertebrate evolution.

    PubMed

    Grier, Harry J; Uribe, Mari Carmen; Lo Nostro, Fabiana L; Mims, Steven D; Parenti, Lynne R

    2016-08-01

    The germinal epithelium, i.e., the site of germ cell production in males and females, has maintained a constant form and function throughout 500 million years of vertebrate evolution. The distinguishing characteristic of germinal epithelia among all vertebrates, males, and females, is the presence of germ cells among somatic epithelial cells. The somatic epithelial cells, Sertoli cells in males or follicle (granulosa) cells in females, encompass and isolate germ cells. Morphology of all vertebrate germinal epithelia conforms to the standard definition of an epithelium: epithelial cells are interconnected, border a body surface or lumen, are avascular and are supported by a basement membrane. Variation in morphology of gonads, which develop from the germinal epithelium, is correlated with the evolution of reproductive modes. In hagfishes, lampreys, and elasmobranchs, the germinal epithelia of males produce spermatocysts. A major rearrangement of testis morphology diagnoses osteichthyans: the spermatocysts are arranged in tubules or lobules. In protogynous (female to male) sex reversal in teleost fishes, female germinal epithelial cells (prefollicle cells) and oogonia transform into the first male somatic cells (Sertoli cells) and spermatogonia in the developing testis lobules. This common origin of cell types from the germinal epithelium in fishes with protogynous sex reversal supports the homology of Sertoli cells and follicle cells. Spermatogenesis in amphibians develops within spermatocysts in testis lobules. In amniotes vertebrates, the testis is composed of seminiferous tubules wherein spermatogenesis occurs radially. Emerging research indicates that some mammals do not have lifetime determinate fecundity. The fact emerged that germinal epithelia occur in the gonads of all vertebrates examined herein of both sexes and has the same form and function across all vertebrate taxa. Continued study of the form and function of the germinal epithelium in vertebrates

  11. Eugregarine trophozoite detachment from the host epithelium via epimerite retraction: fiction or fact?

    PubMed

    Valigurová, Andrea; Michalková, Veronika; Koudela, Bretislav

    2009-09-01

    Eugregarines represent a diverse group of Apicomplexa parasitising numerous invertebrates. Their sporozoites generally develop into epicellular trophozoites attached to the host epithelium by a specialised attachment organelle known as an epimerite. They are considered peculiar protists due to their unique cell architecture and dimensions as well as their attachment strategy which is similar to that of cryptosporidia. Using electron and fluorescence microscopy, the fine structure of the epimerite with associated structures and the mechanism of trophozoite detachment from the host epithelium were studied in Gregarina polymorpha parasitising the intestine of Tenebrio molitor larvae. The epimerite appears to be a very dynamic structure whose shape dramatically changes depending on whether or not it is embedded into the host epithelium. The trophozoite's most fragile zone is the area below the membrane fusion site at the epimerite base. The epimerite plasma membrane forms basal radial ribs which are involved in increasing its surface and strengthening the epimerite-host cell junction. FITC-phalloidin labelling demonstrated the presence of filamentous actin in trophozoites along with its accumulation at the epimerite base and in the apical end of the protomerite, as well as a patch accumulation of filamentous actin in the protomerite of maturing and mature trophozoites. Indirect immunofluorescence revealed the presence of myosin in the cortical zone of the epimerite and in the membrane fusion site area. The data obtained strongly suggest that these structures could facilitate the detachment of a mature trophozoite from the host epithelium. Supported by data presented herein and our previous observations, we propose a new hypothesis on the mechanism of trophozoite detachment from the host epithelium based on epimerite retraction into the protomerite. This is contrary to the commonly accepted hypothesis describing gradual epimerite constriction and subsequent separation

  12. TRANSCRIPTOMIC ANALYSIS OF F344 RAT NASAL EPITHELIUM SUGGESTS THAT THE LACK OF CARCINOGENIC RESPONSE TO GLUTARALDEHYDE IS DUE TO ITS GREATER TOXICITY COMPARED TO FORMALDEHYDE

    EPA Science Inventory

    Formaldehyde is cytotoxic and carcinogenic to the rat nasal respiratory epithelium inducing tumors after 12 months. Glutaraldehyde is also cytotoxic but is not carcinogenic to nasal epithelium even after 24 months. Both aldehydes induce similar acute and subchronic histopathology...

  13. Surface modification of cellulose nanocrystals

    NASA Astrophysics Data System (ADS)

    Eyley, Samuel; Thielemans, Wim

    2014-06-01

    Chemical modification of cellulose nanocrystals is an increasingly popular topic in the literature. This review analyses the type of cellulose nanocrystal modification reactions that have been published in the literature thus far and looks at the steps that have been taken towards analysing the products of the nanocrystal modifications. The main categories of reactions carried out on cellulose nanocrystals are oxidations, esterifications, amidations, carbamations and etherifications. More recently nucleophilic substitutions have been used to introduce more complex functionality to cellulose nanocrystals. Multi-step modifications are also considered. This review emphasizes quantification of modification at the nanocrystal surface in terms of degree of substitution and the validity of conclusions drawn from different analysis techniques in this area. The mechanisms of the modification reactions are presented and considered with respect to the effect on the outcome of the reactions. While great strides have been made in the quality of analytical data published in the field of cellulose nanocrystal modification, there is still vast scope for improvement, both in data quality and the quality of analysis of data. Given the difficulty of surface analysis, cross-checking of results from different analysis techniques is fundamental for the development of reliable cellulose nanocrystal modification techniques.

  14. Surface Modification of Intraocular Lenses

    PubMed Central

    Huang, Qi; Cheng, George Pak-Man; Chiu, Kin; Wang, Gui-Qin

    2016-01-01

    Objective: This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs). Data Sources: All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect. Study Selection: The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded. Results: Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO2, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments. Conclusion: The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs. PMID:26830993

  15. Body Modification and Suicidal Behavior

    ERIC Educational Resources Information Center

    Hicinbothem, Julie; Gonsalves, Sonia; Lester, David

    2006-01-01

    In a large sample of individuals who belong to a website for body modification, having body modifications (e.g., piercings, tattoos, scarification and surgical procedures) was associated with a higher incidence of prior suicidality (i.e., suicidal ideation and attempted suicide). However, controls for self-reported depression weakened the strength…

  16. Beta-agonists and secretory cell number and intracellular glycoproteins in airway epithelium. The effect of isoproterenol and salbutamol.

    PubMed Central

    Jones, R.; Reid, L.

    1979-01-01

    This study describes the effect of systemic administration of the beta-adrenergic agonists isoproterenol and salbutamol on the secretory cell populations in seven regions of rat airway epithelium (three extrapulmonary and four intrapulmonary) and on the size of salivary glands and heart. Isoproterenol (a nonselective beta-adrenergic agonist) significantly increases secretory cell number in all airway regions except the midtrachea; salbutamol (a selective beta 2 agonist) increases secretory cell number only in proximal and peripheral regions. The absolute number of secretory cells is greatest in the most peripheral region after isoproterenol administration and in the most proximal region after salbutamol, although both drugs produce the greatest relative increase at the periphery. In proximal and, particularly, peripheral regions, the increase by isoproterenol (less than 3- and 14-fold, respectively) is greater than by salbutamol (less than 2- and less than 3-fold, respectively). In all airway regions, both drugs modify intracellular glycoprotein in the secretory cell population; within a given region, modification is much the same. In the most proximal region, the population of cells synthesizing only granules of neutral glycoprotein significantly increases while in other regions increase is in cells synthesizing only granules of acid. A significant shift in glycoprotein synthesis occurs whether or not the secretory cell population is increased, which suggests that existing as well as newly appearing cells modify their product. Isoproterenol significantly increases the size of the parotid and submaxillary glands; salbutamol increases the size of the parotid only. Isoproterenol significantly increases the weight of both ventricles of the heart; salbutamol has no such effect. PMID:36762

  17. Damage to lens fiber cells causes TRPV4-dependent Src family kinase activation in the epithelium.

    PubMed

    Shahidullah, M; Mandal, A; Delamere, N A

    2015-11-01

    The bulk of the lens consists of tightly packed fiber cells. Because mature lens fibers lack mitochondria and other organelles, lens homeostasis relies on a monolayer of epithelial cells at the anterior surface. The detection of various signaling pathways in lens epithelial cells suggests they respond to stimuli that influence lens function. Focusing on Src Family Kinases (SFKs) and Transient Receptor Potential Vanilloid 4 (TRPV4), we tested whether the epithelium can sense and respond to an event that occurs in fiber mass. The pig lens was subjected to localized freeze-thaw (FT) damage to fibers at posterior pole then the lens was incubated for 1-10 min in Krebs solution at 37 °C. Transient SFK activation in the epithelium was detectable at 1 min. Using a western blot approach, the ion channel TRPV4 was detected in the epithelium but was sparse or absent in fiber cells. Even though TRPV4 expression appears low at the actual site of FT damage to the fibers, SFK activation in the epithelium was suppressed in lenses subjected to FT damage then incubated with the TRPV4 antagonist HC067047 (10 μM). Na,K-ATPase activity was examined because previous studies report changes of Na,K-ATPase activity associated with SFK activation. Na,K-ATPase activity doubled in the epithelium removed from FT-damaged lenses and the response was prevented by HC067047 or the SFK inhibitor PP2 (10 μM). Similar changes were observed in response to fiber damage caused by injection of 5 μl hyperosmotic NaCl or mannitol solution beneath the surface of the posterior pole. The findings point to a TRPV4-dependent mechanism that enables the epithelial cells to detect remote damage in the fiber mass and respond within minutes by activating SFK and increasing Na,K-ATPase activity. Because TRPV4 channels are mechanosensitive, we speculate they may be stimulated by swelling of the lens structure caused by damage to the fibers. Increased Na,K-ATPase activity gives the lens greater capacity to

  18. Damage to lens fiber cells causes TRPV4-dependent Src family kinase activation in the epithelium.

    PubMed

    Shahidullah, M; Mandal, A; Delamere, N A

    2015-11-01

    The bulk of the lens consists of tightly packed fiber cells. Because mature lens fibers lack mitochondria and other organelles, lens homeostasis relies on a monolayer of epithelial cells at the anterior surface. The detection of various signaling pathways in lens epithelial cells suggests they respond to stimuli that influence lens function. Focusing on Src Family Kinases (SFKs) and Transient Receptor Potential Vanilloid 4 (TRPV4), we tested whether the epithelium can sense and respond to an event that occurs in fiber mass. The pig lens was subjected to localized freeze-thaw (FT) damage to fibers at posterior pole then the lens was incubated for 1-10 min in Krebs solution at 37 °C. Transient SFK activation in the epithelium was detectable at 1 min. Using a western blot approach, the ion channel TRPV4 was detected in the epithelium but was sparse or absent in fiber cells. Even though TRPV4 expression appears low at the actual site of FT damage to the fibers, SFK activation in the epithelium was suppressed in lenses subjected to FT damage then incubated with the TRPV4 antagonist HC067047 (10 μM). Na,K-ATPase activity was examined because previous studies report changes of Na,K-ATPase activity associated with SFK activation. Na,K-ATPase activity doubled in the epithelium removed from FT-damaged lenses and the response was prevented by HC067047 or the SFK inhibitor PP2 (10 μM). Similar changes were observed in response to fiber damage caused by injection of 5 μl hyperosmotic NaCl or mannitol solution beneath the surface of the posterior pole. The findings point to a TRPV4-dependent mechanism that enables the epithelial cells to detect remote damage in the fiber mass and respond within minutes by activating SFK and increasing Na,K-ATPase activity. Because TRPV4 channels are mechanosensitive, we speculate they may be stimulated by swelling of the lens structure caused by damage to the fibers. Increased Na,K-ATPase activity gives the lens greater capacity to

  19. [Formation of basal bodies in the ciliary epithelium of molluscs Buccinum undatum L. and Lymnaea stagnalis L].

    PubMed

    Domaratskiĭ, K E; Onishchenko, G E

    2002-01-01

    Electron microscopic studies of the leg ciliary epithelium was carried out in two mollusks. In the epithelium of the leg of adult animals, the centrioles were mostly formed de novo with participation of deuterosomes during the formation of basal bodies. Transformation of the centriolar cylinder in a mature basal body is accompanied by the cylinder elongation and appearance of pericentriolar structures, such as rootlet system, basal legs, and basal plate. Centriolegenesis proceeds in both ciliate and nonciliate (with microvilli) cells of the epithelium. It has been proposed that the cell with microvilli represent a transitional stage in differentiation of the ciliary cells.

  20. Chromatin modifications and their function.

    PubMed

    Kouzarides, Tony

    2007-02-23

    The surface of nucleosomes is studded with a multiplicity of modifications. At least eight different classes have been characterized to date and many different sites have been identified for each class. Operationally, modifications function either by disrupting chromatin contacts or by affecting the recruitment of nonhistone proteins to chromatin. Their presence on histones can dictate the higher-order chromatin structure in which DNA is packaged and can orchestrate the ordered recruitment of enzyme complexes to manipulate DNA. In this way, histone modifications have the potential to influence many fundamental biological processes, some of which may be epigenetically inherited. PMID:17320507

  1. The coelomic epithelium transcriptome from a clonal sea star, Coscinasterias muricata.

    PubMed

    Gabre, Jonatan L; Martinez, Pedro; Nilsson Sköld, Helen; Ortega-Martinez, Olga; Abril, Josep F

    2015-12-01

    Coscinasterias is a cosmopolitan genus of large asteroid sea stars with the ability of somatic fission as a clonal reproductive strategy. During fission, the animals tear themselves apart across their central disc, where the lost body parts are regenerated afterwards. Here, we have sequenced and subsequently analysed the transcriptome of the coelomic epithelium of a clonal Coscinasterias muricata specimen from New Zealand. Out of the total 389,768 raw reads, 11,344 contigs were assembled and grouped into functions. Raw read and assembled contig sequences are available at NCBI (BioSample: SAMN03371637), while the annotated assembly can be accessed through the project transcriptome browser (compgen.bio.ub.edu/gbrowse/starfish_transcriptome/). Our data is valuable for future detailed exploration of the coelomic epithelium functions as well as for a better understanding of sea star physiology.

  2. Circadian variation of the cell proliferation in the jejunal epithelium of rats at weaning phase.

    PubMed

    Gomes, J R; Pereira, A A M; Barth, L; Silva, J S; Leite, M L; Wille, A C M; Soares, M A M

    2005-06-01

    Circadian variation in cell proliferation of the jejunal epithelium of 18-day-old rats was studied using the 2-h arrested metaphase score and crypt isolation method. A continuous decrease in the arrested metaphases occurred from 07.00 h to 13.00 h. From 17.00 h arrested metaphase values increased and were maintained at the higher level during the dark period as showed by Cosinor analyses (P < 0.05). These results indicate that in the young rat there is already a circadian variation in jejunal epithelial cell proliferation as early as 18 days. We can even suggest that the presence of a circadian rhythm at weaning contributes to the steady state of cell proliferation in the intestinal epithelium observed in adult life.

  3. [Human amniotic epithelium (HAE) as a possible source of stem cells (SC)].

    PubMed

    García-López, Guadalupe; García-Castro, Irma Lydia; Avila-González, Daniela; Molina-Hernández, Anayansi; Flores-Herrera, Héctor; Merchant-Larios, Horacio; Díaz-Martínez, Fabián

    2015-01-01

    There have been major recent advances in the field of developmental biology due to the investigation on stem cells (SC). Stem cells are characterized by their capacity of auto-renewal and differentiation to different cellular phenotypes. Based on the developmental stage, they can be classified into two different types: embryonic SCs and adult SCs. It has been widely reported that several problems need to be resolved before their possible clinical applications. As a result, fetal membranes have been suggested as an alternative source of SCs. In the human amniotic epithelium, the presence of markers of pluripotent SC´s has been reported, and its capacity as a feeder layer for expansion of different SC types. Also, fetal membranes are a discarded product after delivery, and thus there are not any ethical issues related to its use. In conclusion, the human amniotic epithelium can be a strong candidate for regenerative medicine.

  4. Chemodetection and Destruction of Host Urea Allows Helicobacter pylori to Locate the Epithelium

    PubMed Central

    Huang, Julie Y.; Sweeney, Emily Goers; Sigal, Michael; Zhang, Hai C.; Remington, S. James; Cantrell, Michael A.; Kuo, Calvin J.; Guillemin, Karen; Amieva, Manuel R.

    2015-01-01

    SUMMARY The gastric pathogen Helicobacter pylori interacts intimately with the gastric mucosa to avoid the microbicidal acid in the stomach lumen. The cues H. pylori senses to locate and colonize the gastric epithelium have not been well defined. We show that metabolites emanating from human gastric organoids rapidly attract H. pylori. This response is largely controlled by the bacterial chemoreceptor TlpB, and the main attractant emanating from epithelia is urea. Our previous structural analyses show that TlpB binds urea with high affinity. Here we demonstrate that this tight binding controls highly sensitive responses, allowing detection of urea concentrations as low as 50 nanomolar. Attraction to urea requires that H. pylori urease simultaneously destroys the signal. We propose that H. pylori has evolved a sensitive urea chemodetection and destruction system that allows the bacterium to dynamically and locally modify the host environment to locate the epithelium. PMID:26269952

  5. Effects of centrophenoxine on lipofuscin in the retinal pigment epithelium of old mice.

    PubMed

    Dylewski, D P; Nandy, S; Nandy, K

    1983-01-01

    The effects of centrophenoxine on the retinal pigment epithelium (RPE) of 17 month old female mice have been studied. Animals were injected subcutaneously for 3 months (60 injections) with the drug (0.1 mg/g of body wt) daily in 0.1 M phosphate buffered saline at pH 7.0. The morphological changes in the pigment layers of the retina of both eyes were studied by light and electron microscopy and the lipofuscin pigment was demonstrated by its autofluorescence and ultrastructural characteristics. There was a significant reduction of the lipofuscin pigment in the treated animals, but the melanin pigment remained unchanged. The lipofuscin granules also appeared less osmiophilic and showed a greater preponderance of membranes and vacuoles. Although the precise mechanism of action of the drug is not clear, an increased protective function of the pigment epithelium by the drug has been suggested.

  6. Selachian tooth development: II. Immunolocalization of amelogenin polypeptides in epithelium during secretory amelogenesis in Squalus acanthias.

    PubMed

    Slavkin, H C; Samuel, N; Bringas, P; Nanci, A; Santos, V

    1983-01-01

    We have determined the distribution of amelogenin polypeptides in an order of elasmobranchs using indirect immunofluorescence with rabbit polyclonal antibodies prepared to purified murine amelogenins. We find that amelogenins are definitely present within the inner enamel epithelium prior to the production of the extracellular matrix component termed "enameloid" (row II developing tooth organs). During subsequent stages of selachian tooth development (row III tooth organs), immunofluorescence staining data indicated localization of amelogenin antigens within epithelium as well as the enameloid extracellular matrix. The results from these immunohistochemical studies suggest that the 16-20 kdalton amelogenins, which are characteristic of murine inner enamel epithelial cells undergoing terminal biochemical differentiation into secretory ameloblasts, may also be regarded as molecular markers for amelogenesis in developing teeth in the spiny dogfish, Squalus acanthias.

  7. Chemodetection and Destruction of Host Urea Allows Helicobacter pylori to Locate the Epithelium.

    PubMed

    Huang, Julie Y; Sweeney, Emily Goers; Sigal, Michael; Zhang, Hai C; Remington, S James; Cantrell, Michael A; Kuo, Calvin J; Guillemin, Karen; Amieva, Manuel R

    2015-08-12

    The gastric pathogen Helicobacter pylori interacts intimately with the gastric mucosa to avoid the microbicidal acid in the stomach lumen. The cues H. pylori senses to locate and colonize the gastric epithelium have not been well defined. We show that metabolites emanating from human gastric organoids rapidly attract H. pylori. This response is largely controlled by the bacterial chemoreceptor TlpB, and the main attractant emanating from epithelia is urea. Our previous structural analyses show that TlpB binds urea with high affinity. Here we demonstrate that this tight binding controls highly sensitive responses, allowing detection of urea concentrations as low as 50 nM. Attraction to urea requires that H. pylori urease simultaneously destroys the signal. We propose that H. pylori has evolved a sensitive urea chemodetection and destruction system that allows the bacterium to dynamically and locally modify the host environment to locate the epithelium.

  8. The coelomic epithelium transcriptome from a clonal sea star, Coscinasterias muricata.

    PubMed

    Gabre, Jonatan L; Martinez, Pedro; Nilsson Sköld, Helen; Ortega-Martinez, Olga; Abril, Josep F

    2015-12-01

    Coscinasterias is a cosmopolitan genus of large asteroid sea stars with the ability of somatic fission as a clonal reproductive strategy. During fission, the animals tear themselves apart across their central disc, where the lost body parts are regenerated afterwards. Here, we have sequenced and subsequently analysed the transcriptome of the coelomic epithelium of a clonal Coscinasterias muricata specimen from New Zealand. Out of the total 389,768 raw reads, 11,344 contigs were assembled and grouped into functions. Raw read and assembled contig sequences are available at NCBI (BioSample: SAMN03371637), while the annotated assembly can be accessed through the project transcriptome browser (compgen.bio.ub.edu/gbrowse/starfish_transcriptome/). Our data is valuable for future detailed exploration of the coelomic epithelium functions as well as for a better understanding of sea star physiology. PMID:26321383

  9. Oestrus synchronization treatment induces histomorphological changes on the uterine tube epithelium of the gilt.

    PubMed

    Juárez-Mosqueda, M L; Anzaldúa Arce, S R; Palma Lara, I; García Dalmán, C; Cornejo Cortés, M A; Córdova Izquierdo, A; Villaseñor Gaona, H; Trujillo Ortega, M E

    2015-12-01

    The aim of this study was to determine the histomorphological changes that occurred in response to two treatments for oestrus synchronization in three different regions of the gilt's uterine tubes epithelium: the ampulla (AMP), ampulla-isthmic junction (AIJ) and isthmus (IST). Nine prepuberal gilts were divided into three groups (n = 3): (1) eCG 400 IU and hCG 200 IU (eCG/hCG), (2) progesterone agonist (P4) and (3) control group. The number of secretory cells (stained with periodic acid-Schiff reaction or PAS-positive cells) decreased in the AMP in the P4 treated group when compared to the control group, whereas, no difference was observed in the number of PAS-negative cells in the AMP of the three groups. A significant decrease in the number of PAS-positive cells was observed in the AIJ and IST of the P4 treated group when compared to the eCG/hCG and control groups. An increase in the number of PAS-negative cells was observed in the AIJ and IST in the P4 treated group. The epithelium height in the AMP and AIJ was increased in the eCG/hCG group when compared to the control and P4 groups. In this last group, we observed a reduced height compared with the other two groups for the AIJ. In the IST, there were no significant changes in the epithelium height of the control or the other two groups (eCG/hCG and P4). The epithelial cells of the P4 treated group had the least amount of cytoplasmic granules and the lowest intensity of PAS staining in the AMP, AIJ and IST. Animals treated with eCG/hCG showed an intermediate number of cytoplasmic granules and intensity in all regions evaluated. These data show that P4 treatment for synchronization induces a significant (P < 0.001) decrease of PAS-positive cells and staining intensity of cytoplasmic granules in the different regions studied and an increased number of PAS-negative cells in the AIJ and IST epithelium. Moreover, eCG/hCG treatment increased the height of the epithelium in the AMP and AIJ, while in this last

  10. Oestrus synchronization treatment induces histomorphological changes on the uterine tube epithelium of the gilt.

    PubMed

    Juárez-Mosqueda, M L; Anzaldúa Arce, S R; Palma Lara, I; García Dalmán, C; Cornejo Cortés, M A; Córdova Izquierdo, A; Villaseñor Gaona, H; Trujillo Ortega, M E

    2015-12-01

    The aim of this study was to determine the histomorphological changes that occurred in response to two treatments for oestrus synchronization in three different regions of the gilt's uterine tubes epithelium: the ampulla (AMP), ampulla-isthmic junction (AIJ) and isthmus (IST). Nine prepuberal gilts were divided into three groups (n = 3): (1) eCG 400 IU and hCG 200 IU (eCG/hCG), (2) progesterone agonist (P4) and (3) control group. The number of secretory cells (stained with periodic acid-Schiff reaction or PAS-positive cells) decreased in the AMP in the P4 treated group when compared to the control group, whereas, no difference was observed in the number of PAS-negative cells in the AMP of the three groups. A significant decrease in the number of PAS-positive cells was observed in the AIJ and IST of the P4 treated group when compared to the eCG/hCG and control groups. An increase in the number of PAS-negative cells was observed in the AIJ and IST in the P4 treated group. The epithelium height in the AMP and AIJ was increased in the eCG/hCG group when compared to the control and P4 groups. In this last group, we observed a reduced height compared with the other two groups for the AIJ. In the IST, there were no significant changes in the epithelium height of the control or the other two groups (eCG/hCG and P4). The epithelial cells of the P4 treated group had the least amount of cytoplasmic granules and the lowest intensity of PAS staining in the AMP, AIJ and IST. Animals treated with eCG/hCG showed an intermediate number of cytoplasmic granules and intensity in all regions evaluated. These data show that P4 treatment for synchronization induces a significant (P < 0.001) decrease of PAS-positive cells and staining intensity of cytoplasmic granules in the different regions studied and an increased number of PAS-negative cells in the AIJ and IST epithelium. Moreover, eCG/hCG treatment increased the height of the epithelium in the AMP and AIJ, while in this last

  11. Recent advances in the morphological and functional heterogeneity of the biliary epithelium

    PubMed Central

    Han, Yuyan; Glaser, Shannon; Meng, Fanyin; Francis, Heather; Marzioni, Marco; McDaniel, Kelly; Alvaro, Domenico; Venter, Julie; Carpino, Guido; Onori, Paolo; Gaudio, Eugenio; Alpini, Gianfranco; Franchitto, Antonio

    2014-01-01

    This review focuses on the recent advances related to the heterogeneity of different-sized bile ducts with regard to the morphological and phenotypical characteristics, and the differential secretory, apoptotic and proliferative responses of small and large cholangiocytes to gastrointestinal hormones/peptides, neuropeptides and toxins. We describe several in vivo and in vitro models used for evaluating biliary heterogeneity. Subsequently, we discuss the heterogeneous proliferative and apoptotic responses of small and large cholangiocytes to liver injury and the mechanisms regulating the differentiation of small into large (more differentiated) cholangiocytes. Following a discussion on the heterogeneity of stem/progenitor cells in the biliary epithelium, we outline the heterogeneity of bile ducts in human cholangiopathies. After a summary section, we discuss the future perspectives that will further advance the field of the functional heterogeneity of the biliary epithelium. PMID:23856906

  12. Undiagnosed Borrmann type II gastric cancer due to necrosis and regenerative epithelium

    PubMed Central

    Hur, Joon; Chang, Jae Hyuck; Kim, Byung Kee; Ko, Hoon Young; Lee, Jong Hwan; Kim, Soo Jeong; Song, Mi Ae; Kim, Tae Ho; Kim, Chang Whan; Han, Sok Won

    2014-01-01

    Endoscopic biopsy is essential to the proper diagnosis and treatment of gastric cancer. Unfortunately, the results of endoscopic biopsy are not always the same as what is expected based on gross endoscopic findings. The results of endoscopic biopsy can be negative for malignancy in Borrmann type IV advanced gastric cancer (AGCa) or gastric lymphoma. However, in the case of type II AGCa, repeated biopsies negative for malignancy have not been reported. A 49-year-old male patient underwent esophagogastroduodenoscopy three times due to large gastric ulcer suspected to be Borrmann type II cancer. However, three repeat endoscopic biopsies with multiple specimens showed necrosis and superficial regenerative epithelium without malignant findings. The patient underwent laparoscopic distal gastrectomy with D2 lymph node dissection. The surgical specimen revealed that the mucosal layer was completely replaced with regenerative epithelium without cancer cells. PMID:25071361

  13. Cytological response of palatal epithelium to TiN-coated CoCr alloy denture.

    PubMed

    Lukomska-Szymańska, Monika; Brzeziński, Piotr M; Zieliński, Andrzej; Sokołowski, Jerzy

    2012-04-24

    The aim of this study was to assess the impact of titanium nitride coatings on CoCr alloy metal parts in framework dentures on human palatal epithelium cytology compared to framework dentures made with the same alloy but without titanium nitride coating, and to acrylic dentures. Every prosthetic restoration introduced into the oral cavity and remaining in direct contact with the palate exhibits a varied and harmful effect on the state of the palatal epithelium by disturbing its keratinization. CoCr alloy dentures produce a significantly greater perturbation of keratinization compared to acrylic dentures. There is no evidence showing that a titanium nitride coating of the CoCr alloy plays a protective role in the environment of the oral cavity.

  14. Ingestion of colloid in a keratinized epithelium and its localization in membrane-coating granules.

    PubMed

    Hayward, A F

    1976-04-01

    An electron-dense tracer (Thorotrast) was injected into the lamina propria of the keratinized epithelium of the buccal mucosa of rats. Electron microscopy showed that it crossed the basal lamina and penetrated the intercellular spaces of the epithelium up to the proximal layers of the stratum granulosum. Thorotrast was ingested by the epithelial cells in the stratum basale and stratum spinosum and localized in large vesicles and eventually in the membrane-coating granules. The latter, already known to contain lysosomal enzymes, are therefore to be regarded as secondary lysosomes formed in part as a sequel of endocytosis in deeper cell layers. The postulated origin of MCGs directly from the Golgi apparatus is rendered less likely by this observation. Thorotrast remaining in the cells when keratinization is completed is either dispersed into the cytoplasm or else incorporated into keratohyalin granules.

  15. Origin of Ameloblastoma From Basal Cells of the Oral Epithelium- Establishing the Relation Using Neuroectodermal Markers

    PubMed Central

    Suneela, S; Narayan, T V; Shreedhar, Balasundari; Mohanty, Leeky; Shenoy, Sadhana; Swaminathan, Uma

    2014-01-01

    Background and Objectives: Basal cell layer of the oral epithelium has been rightfully regarded as a potential source of odontogenic tumours and cysts, but, without substantial evidence. Also, whether the basal cell layer retains within it, some properties of ectomesenchyme, which was imbibed during the early embryogenesis and hence its neuroectodermal relation, is not known. Here, an attempt is made to establish the hidden neuroectodermal potential of the oral epithelium, especially the basal layer, by observing the expression of known neuroectodermal markers, NSE (Neuron Specific Enolase), Synaptophysin and CD99. The expression of the same markers has also been studied in Ameloblastoma, connecting it with oral epithelium, in turn establishing basal cell layer as a potential source of Ameloblastoma. Materials and Methods: Sections of formalin fixed, paraffin embedded tissue samples of 20 cases of Ameloblastoma and 10 cases of Normal Retromolar mucosa, were stained immunohistochemically with NSE, Synaptophysin, CD99 and also with CK-19 and evaluated for positive expression. Results: Positive reaction was obtained in all the cases of Ameloblastoma and NRM (Normal Retromolar mucosa) with NSE, all the cases of Ameloblastoma and eight cases of NRM with Synaptophysin and in six cases of Ameloblastoma and NRM with CD99. The staining was diffuse and more marked in case of NSE than Synaptophysin and CD99. CK19 staining done to assure that the tissue antigenicity was maintained was positive in all the samples. Interpretation and Conclusion: A strong relationship between the neuroectoderm, Ameloblastoma and the basal layer of the oral epithelium is established by the study. It favours the hypothesis that the basal cell layer of oral mucosa may be the sought out culprit in most cases of the Ameloblastomas, especially those occurring in the non-tooth bearing area. This would call for the need to incorporate additional therapy in the form of mucosal striping along with the

  16. Caspase-3 expression in normal oral epithelium, oral submucous fibrosis and oral squamous cell carcinoma

    PubMed Central

    Veeravarmal, Veeran; Austin, Ravi David; Siddavaram, Nagini; Thiruneelakandan, Sambanthan; Nassar, Mohamed Hanifa Mohamed

    2016-01-01

    Context: The epithelium atrophy, as the oral submucous fibrosis (OSMF) progresses, is believed to be an after effect of stromal fibrosis, hyalinization, decrease in vascularity and cellularity and is considered as “ischemic atrophy.” Due to hypoxia, caspase-3 get activation and subsequent decrease in viable cell count can occur. Aims and Objectives: To determine caspase-3 expression in various grades of OSMF and oral squamous cell carcinoma (OSCC) to find out whether upregulation of apoptosis is responsible for the epithelial changes in OSMF. Subjects and Methods: The control tissue (15 samples from normal oral mucosa) and study group comprising 97 cases of OSMF of different grades and OSCC associated with OSMF were stained with caspase-3 antibody, and the percentage of positive cells was calculated using ImageJ software. Statistical Analysis: The results obtained were statistically analyzed using ANOVA and Tukey's honest significance difference test and Mann–Whitney U-test. Results: There was a nuclear expression of caspase-3 in basal and parabasal layers of normal epithelium. There was cytoplasmic expression of caspase-3 in OSMF without dysplasia, total absence of caspase-3 expression in dysplastic epithelium and in majority cases of OSCC. The caspase-3 percentage was increased in OSMF (0%–53%) when compared with OSCC (0%–8%). The statistical comparison of caspase-3 among normal, OSMF and OSCC patients revealed significant correlation (P < 0.00010). The comparison within different grades of OSMF and between dysplastic and nondysplastic epithelium OSMF also showed significance (P < 0.019). Conclusions: The decreased expression of caspase-3 in disease progression reflects its role in the malignant transformation. PMID:27721610

  17. Ion transport across CF and normal murine olfactory and ciliated epithelium

    PubMed Central

    Grubb, B. R.; Rogers, T. D.; Boucher, R. C.; Ostrowski, L. E.

    2009-01-01

    The nasal epithelium of the cystic fibrosis (CF) mouse has been used extensively in CF research because it exhibits ion transport defects similar to those of human CF airways. This tissue is composed of ∼50% olfactory (OE) and ∼50% ciliated epithelium (CE), and on the basis of previous observations, we hypothesized that a significant fraction of the bioelectric signals from murine nasal tissue may arise from OE rather than CE, while CE is the target tissue for CF gene therapy. We compared the bioelectric properties of isolated OE from the nasal cavity and CE from the nasopharynx in Ussing chamber studies. Hyperabsorption of Na+ [amiloride response; CF vs. wild type (WT)] was ∼7.5-fold greater in the OE compared with the CE. The forskolin response in native tissues did not reliably distinguish genotypes, likely due to a cyclic nucleotide-gated cation conductance in OE and a calcium-mediated Cl− conductance in CE. By potential difference assay, hyperabsorption of Na+ (CF vs. WT) and the difference in response to apical 0 Cl− buffer (CF vs. WT) were ∼2-fold greater in the nasal cavity compared with the nasopharynx. Our studies demonstrate that in the CF mouse, both the hyperabsorption of Na+ and the Cl− transport defect are of larger magnitude in the OE than in the CE. Thus, while the murine CF nasal epithelium is a valuable model for CF studies, the bioelectrics are likely dominated by the signals from the OE, and assays of the nasopharynx may be more specific for studying the ciliated epithelium. PMID:19321738

  18. IL-1β and TSH disturb thyroid epithelium integrity in autoimmune thyroid diseases.

    PubMed

    Rebuffat, Sandra A; Kammoun-Krichen, Maha; Charfeddine, Ilhem; Ayadi, Hammadi; Bougacha-Elleuch, Noura; Peraldi-Roux, Sylvie

    2013-03-01

    Pro-inflammatory cytokines such as IL-1β and TNFα are known to affect thyroid function. They stimulate IL-6 secretion and modify epithelium integrity by altering junction proteins. To study the role of cytokines on thyroid epithelia tightness in autoimmune thyroid diseases (AITD), we analyzed the expression profiles of junction proteins (ZO-1, Claudin, JAM-A) and cytokines in human thyroid slices and also investigated the effect of IL-1β on the epithelium integrity in primary cultures of human thyrocytes. Junction proteins expression (ZO-1, Claudin, JAM-A) has been analyzed by immunohistochemistry on thyroid slices and by Western blot on membrane proteins extracted from thyrocytes of patients suffering from Graves and Hashimoto diseases. The high expression of junction proteins we found on Graves' disease thyroid slices as well as in cell membrane extracts acknowledges the tightness of thyroid follicular cells in this AITD. In contrast, the reduced expression of JAM and ZO-1 in thyroid cells from patients suffering from Hashimoto thyroiditis is in agreement with the loss of thyroid follicular cell integrity that occurs in this pathology. Concerning the effects on epithelium integrity of TSH and of the pro-inflammatory cytokine IL-1β in primary cultures of human thyroid cells, TSH appeared able to modify JAM-A localization but without any change in the expression levels of JAM-A, Claudin and ZO-1. Inversely, IL-1β provoked a decrease in the expression of- and a redistribution of both, Claudin and ZO-1 without modifying the expression and sub-cellular distribution patterns of JAM-A in thyroid cells. These results demonstrate (i) that Hashimoto's- and Graves' diseases display different junction proteins expression patterns with a loss of epithelium integrity in the former and (ii) that IL-1β modifies thyroid epithelial tightness of human thyrocytes by altering the expression and localization of junction proteins. Therefore, IL-1β could play a role in the

  19. An endocannabinoid system is present in the mouse olfactory epithelium but does not modulate olfaction

    PubMed Central

    Hutch, Chelsea; Hillard, Cecilia J.; Jia, Cuihong; Hegg, Colleen C.

    2015-01-01

    Endocannabinoids modulate a diverse array of functions including progenitor cell proliferation in the central nervous system, and odorant detection and food intake in the mammalian central olfactory system and larval Xenopus laevis peripheral olfactory system. However, the presence and role of endocannabinoids in the peripheral olfactory epithelium has not been examined in mammals. We found the presence of cannabinoid type 1 (CB1) and cannabinoid type 2 (CB2) receptor protein and mRNA in the olfactory epithelium. Using either immunohistochemistry or calcium imaging we localized CB1 receptors on neurons, glia like sustentacular cells, microvillous cells and progenitor-like basal cells. To examine the role of endocannabinoids, CB1 and CB2 receptor deficient (CB1−/−/CB2−/−) mice were used. The endocannabinoid 2-arachidonylglycerol (2-AG) was present at high levels in both C57BL/6 wildtype and CB1−/−/CB2−/− mice. 2-AG synthetic and degradative enzymes are expressed in wildtype mice. A small but significant decrease in basal cell and olfactory sensory neuron numbers was observed in CB1−/−/CB2−/− mice compared to wildtype mice. The decrease in olfactory sensory neurons did not translate to impairment in olfactory-mediated behaviors assessed by the buried food test and habituation/dishabituation test. Collectively, these data indicate the presence of an endocannabinoid system in the mouse olfactory epithelium. However, unlike in tadpoles, endocannabinoids do not modulate olfaction. Further investigation on the role of endocannabinoids in progenitor cell function in the olfactory epithelium is warranted. PMID:26037800

  20. Adenoma of the Nonpigmented Ciliary Body and Iris Epithelium in Mexican Mestizo Patients

    PubMed Central

    Serna-Ojeda, Juan Carlos; Ariza-Camacho, Enrique; Collado-Solórzano, Alberto; Flores-Sánchez, Blanca C.; Rodríguez-Reyes, Abelardo A.; Fulda-Graue, Emiliano

    2015-01-01

    The adenoma of the nonpigmented ciliary epithelium is a benign rare tumor, which may present with different clinical characteristics and requires resection along with histopathologic analysis and the identification of specific immunohistochemical markers for an accurate diagnosis. Here, we report a case series of 4 patients in a Mexican mestizo population with this diagnosis, their clinical features, the ultrasound imaging characteristics and the histopathological and immunohistochemical findings. PMID:27171918

  1. Structural Development, Cellular Differentiation and Proliferation of the Respiratory Epithelium in the Bovine Fetal Lung.

    PubMed

    Drozdowska, J; Cousens, C; Finlayson, J; Collie, D; Dagleish, M P

    2016-01-01

    Fetal bovine lung samples of 11 different gestational ages were assigned to a classical developmental stage based on histological morphology. Immunohistochemistry was used to characterize the morphology of forming airways, proliferation rate of airway epithelium and the presence of epithelial cell types (i.e. ciliated cells, club cells, neuroepithelial cells (NECs) and type II pneumocytes). Typical structural organization of pseudoglandular (84-98 days gestational age [DGA]), canalicular (154-168 DGA) and alveolar (224-266 DGA) stages was recognized. In addition, transitional pseudoglandular-canalicular (112-126 DGA) and canalicular-saccular (182 DGA) morphologies were present. The embryonic stage was not observed. A significantly (P <0.05) higher proliferation rate of pulmonary epithelium, on average 5.5% and 4.4% in bronchi and bronchioles, respectively, was present in the transitional pseudoglandular-canalicular phase (112-126 DGA) compared with all other phases, while from 8 weeks before term (224-266 DGA) proliferation had almost ceased. The first epithelial cells identified by specific marker proteins in the earliest samples available for study (84 DGA) were ciliated cells and NECs. Club cells were present initially at 112 DGA and type II pneumocytes at 224 DGA. At the latest time points (224-226 DGA) these latter cell types were still present at a much lower percentage compared with adult cattle. This study characterized bovine fetal lung development by histological morphology and cellular composition of the respiratory epithelium and suggests that the apparent structural anatomical maturity of the bovine lung at term is not matched by functional maturity of the respiratory epithelium.

  2. The role of reactive oxygen and nitrogen species in the response of airway epithelium to particulates.

    PubMed Central

    Martin, L D; Krunkosky, T M; Dye, J A; Fischer, B M; Jiang, N F; Rochelle, L G; Akley, N J; Dreher, K L; Adler, K B

    1997-01-01

    Epidemiologic and occupational studies indicate adverse health effects due to inhalation of particulate air pollutants, but precise biologic mechanisms responsible have yet to be fully established. The tracheobronchial epithelium forms the body's first physiologic barrier to such airborne pollutants, where ciliary movement functions to remove the offending substances caught in the overlying mucus layer. Resident and infiltrating phagocytic cells also function in this removal process. In this paper, we examine the role of reactive oxygen and nitrogen species (ROS/RNS) in the response of airway epithelium to particulates. Some particulates themselves can generate ROS, as can the epithelial cells, in response to appropriate stimulation. In addition, resident macrophages in the airways and the alveolar spaces can release ROS/RNS after phagocytosis of inhaled particles. These macrophages also release large amounts of tumor necrosis factor alpha (TNF-alpha), a cytokine that can generate responses within the airway epithelium dependent upon intracellular generation of ROS/RNS. As a result, signal transduction pathways are set in motion that may contribute to inflammation and other pathobiology in the airway. Such effects include increased expression of intercellular adhesion molecule 1, interleukin-6, cytosolic and inducible nitric oxide synthase, manganese superoxide dismutase, cytosolic phospholipase A2, and hypersecretion of mucus. Ultimately, ROS/RNS may play a role in the global response of the airway epithelium to particulate pollutants via activation of kinases and transcription factors common to many response genes. Thus, defense mechanisms involved in responding to offending particulates may result in a complex cascade of events that can contribute to airway pathology. PMID:9400742

  3. Nerve-epithelium association in the periodontal ligament of guinea pig teeth.

    PubMed

    Jayawardena, Chantha K; Takano, Yoshiro

    2006-07-01

    Several lines of evidence have suggested that periodontal nerves have other roles besides sensory function. Exploring the distribution pattern of nerves in relation to other structures within the periodontal ligament of various species should be important to understand their roles within the ligament. This study investigated whether any association exists between the nerves and the epithelial cells in the periodontal ligament of continuously erupting guinea pig molars, which show distinct enamel epithelium layers among the cementum pearls. Ten guinea pigs were fixed by vascular perfusion and jaw sections were processed for immunohistochemistry of protein gene product 9.5 (PGP 9.5), growth-associated protein-43 (GAP-43) and glia-specific S-100 protein, and for enzyme histocytochemistry of cholinesterase. Nerves that were immunopositive for the above neuronal markers were located predominantly in the alveolus-related part of the periodontal ligament. Some nerves, immunoreactive for PGP 9.5 and GAP-43, were also found in the tooth-related part (TRP) of the periodontal ligament close to the tooth surface. PGP 9.5-positive nerves in the TRP appeared very thin and terminated by making loops or plexus-like structures in close apposition to the epithelium layers, overlying the enamel surface in between cementum pearls. Such an intimate association between nerves and the enamel epithelium was not found in the labial periodontal tissue of incisors or the apical growing end of the molar, where periodontal fibre attachment was indistinct. The association between nerves and epithelium in the periodontal ligament of guinea pig molar is site specific and is only seen in the presence of cementum, suggesting that this association is related to the attachment function of the ligament. PMID:16510117

  4. Adaptation of a nematode parasite to living within the mammalian epithelium.

    PubMed

    Tilney, Lewis G; Connelly, Patricia S; Guild, Gregory M; Vranich, Kelly A; Artis, David

    2005-11-01

    Trichuris muris is a large metazoan pathogen that has been proposed to live intracellularly within living host intestinal epithelial cells. We sought to determine how Trichuris bores its way through the mucosal epithelium and to elucidate the parasite strategies for taking advantage of this intracellular niche. Since the apical surface of the mucosal epithelium is stabilized by the actin cytoskeleton and cell junctions, it remains intact over the worm following its entry into cells. In contrast, non-stabilized lateral membranes of the host epithelial cells are ruptured and cells are killed to form an inert syncytial tunnel. The ventral surface of the nematode worm is studded by pores that overlie bacillary cells; these pores penetrate through the cuticle and are in direct contact with host cytoplasm. From scanning electron micrographs of isolated worms, we calculate that each adult contains approximately 50,000 bacillary cells. The apical surface of the bacillary cells is extensively folded into plicae 40 nm in diameter, thereby increasing the surface area many-fold. Bacillary cells lack organelles for enzyme synthesis and secretion and fail to export protons. However, by confocal light microscopy it was observed that fluorescent macromolecules in excess of 100,000 Da can penetrate into the pores. Taken together, we conclude that the bacillary cells are essential for living inside host epithelium and function predominantly in absorption of soluble molecules from the host mucosal cytoplasm, in essence behaving as an external gut epithelium that is protected from abrasion by the cuticle that surrounds the openings of the bacillary cells. PMID:16217807

  5. Degeneration and recovery of rat olfactory epithelium following inhalation of dibasic esters.

    PubMed

    Keenan, C M; Kelly, D P; Bogdanffy, M S

    1990-08-01

    Dibasic esters (DBE) are solvent mixtures used in the paint and coating industry. To evaluate the potential subchronic toxicity of DBE, groups of male and female rats were exposed for periods of up to 13 weeks to DBE concentrations of 0, 20, 76, or 390 mg/m3. After approximately 7 and 13 weeks of exposure, 10 rats per sex per group were subjected to clinical chemical, hematological, and urine analyses. Following 7 or 13 weeks of exposure, 10 or 20 rats per sex per group, respectively, were euthanized. An additional 10 rats were euthanized following a 6-week recovery period. A standard profile of tissues, including four levels of nasal cavity, was evaluated histopathologically. After 7 weeks of exposure, slight degeneration of the olfactory epithelium was observed in both male and female rats at 76 and 390 mg/m3. After 13 weeks, degeneration of the olfactory epithelium was present at all DBE concentrations in female rats, but only at the mid and high concentrations in male rats. The severity and incidence of the lesions were concentration related for both sexes with female rats being more sensitive than males. Following the recovery period, histological changes compatible with repair in the olfactory mucosa included an absence of degeneration, focal disorganization of the olfactory epithelium, and respiratory metaplasia. All other tissues were macroscopically normal. No other signs of toxicity were indicated by the other parameters evaluated. Inhalation studies of other esters demonstrate similar pathology in the olfactory epithelium. Since olfactory mucosa is rich in carboxylesterase activity, acids may be the toxic metabolites of these compounds. This hypothetical mechanism may explain the sensitivity of olfactory tissue to the effects of DBE.

  6. Substrate metabolism in isolated rat jejunal epithelium. Analysis using /sup 14/C-radioisotopes

    SciTech Connect

    Mallet, R.T.

    1986-01-01

    The jejunal epithelium absorbs nutrients from the intestinal lumen and is therefore the initial site for metabolism of these compounds. The purpose of this investigation is to analyze substrate metabolism in a preparation of jejunal epithelium relatively free of other tissues. Novel radioisotopic labelling techniques allow quantitation of substrate metabolism in the TCA cycle, Embden-Meyerhof (glycolytic) pathway, and hexose monophosphate shunt. For example, ratios of /sup 14/CO/sub 2/ production from pairs of /sup 14/C-pyruvate, and /sup 14/C-succinate radioisotopes (CO/sub 2/ ratios) indicate the probability of TCA cycle intermediate efflux to generate compounds other than CO/sub 2/. With (2,3-/sup 14/C)succinate as tracer, the ratio of /sup 14/C in carbon 4 + 5 versus carbon 2 + 3 of citrate, the citrate labelling ratio, equals the probability of TCA intermediate flux to the acetyl CoA-derived portion of citrate versus flux to the oxaloacetate-derived portion. The principal metabolic substrates for the jejunal epithelium are glucose and glutamine. CO/sub 2/ ratios indicate that glutamine uptake and metabolism is partially Na/sup +/-independent, and is saturable, with a half-maximal rate at physiological plasma glutamine concentrations. Glucose metabolism in the jejunal epithelium proceeds almost entirely via the Embden-Meyerhof pathway. Conversion of substrates to multi-carbon products in this tissue allows partial conservation of reduced carbon for further utilization in other tissues. In summary, metabolic modeling based on /sup 14/C labelling ratios is a potentially valuable technique for analysis of metabolic flux patterns in cell preparations.

  7. An immunohistological study of cytokeratin 20 in human and mammalian oral epithelium.

    PubMed

    Barrett, A W; Cort, E M; Patel, P; Berkovitz, B K

    2000-10-01

    Cytokeratin (CK) 20 is a low molecular-weight intermediate filament reportedly expressed only by benign and malignant gastrointestinal epithelium, urothelium and Merkel cells. The main aims here were to map its expression in normal oral mucosa of humans and other mammals, and to determine whether it was expressed by abnormal human oral epithelium. Salivary and odontogenic epithelium were also analysed. An immunoperoxidase method was used on wax-embedded and cryostat sections. In addition, double-labelling experiments were undertaken to determine the association between CK 20 expression and that of CK 8/18 or S100 protein. Normal human oral mucosa from four sites, together with abdominal skin, was studied in autopsy samples from 32 individuals. CK 20-positive, basally situated, round or angular cells, consistent with Merkel cells, were recorded in 24/32 (75.0%) samples of mandibular gingiva, 25/32 (78.1%) samples of hard palate, 7/32 (21.9%) samples of buccal mucosa, 0/32 samples of lateral border of tongue, and 2/32 (6.3%) samples of abdominal skin. Double-labelling showed that all CK 20-positive Merkel cells also expressed CK 8/18 and S100. The only other cells to express CK 20 were human taste buds. There was no expression by dysplastic or invasive oral epithelium from biopsy samples. Colonic mucosa showed luminal-cell positivity in man, marmoset, ferret, rabbit and guinea-pig, but oral mucosa was universally negative in non-human species. It is concluded that in oral mucosa CK 20 is a specific marker of Merkel cells and taste buds, that Merkel cells are more frequently present in keratinized than non-keratinized oral mucosa, that CK 20-positive Merkel cells are also S100-positive, that there may be interspecies variations in CK 20 polypeptide composition and that, by contrast to urothelium, CK 20 has no value in the diagnosis of oral epithelial dysplasia.

  8. Chatting histone modifications in mammals

    PubMed Central

    Izzo, Annalisa

    2010-01-01

    Eukaryotic chromatin can be highly dynamic and can continuously exchange between an open transcriptionally active conformation and a compacted silenced one. Post-translational modifications of histones have a pivotal role in regulating chromatin states, thus influencing all chromatin dependent processes. Methylation is currently one of the best characterized histone modification and occurs on arginine and lysine residues. Histone methylation can regulate other modifications (e.g. acetylation, phosphorylation and ubiquitination) in order to define a precise functional chromatin environment. In this review we focus on histone methylation and demethylation, as well as on the enzymes responsible for setting these marks. In particular we are describing novel concepts on the interdependence of histone modifications marks and discussing the molecular mechanisms governing this cross-talks. PMID:21266346

  9. Ultrastructural changes of the midgut epithelium in Isohypsibius granulifer granulifer Thulin, 1928 (Tardigrada: Eutardigrada) during oogenesis.

    PubMed

    Rost-Roszkowska, Magdalena M; Poprawa, Izabela; Wójtowicz, Maria; Kaczmarek, Lukasz

    2011-04-01

    The midgut epithelium of Isohypsibius granulifer granulifer (Eutardigrada) is composed of columnar digestive cells. At its anterior end, a group of cells with cytoplasm which differs from the cytoplasm of digestive cells is present. Probably, those cells respond to crescent-like cells (midgut regenerative cells) described for some tardigrade species. Their mitotic divisions have not been observed. We analyzed the ultrastructure of midgut digestive cells in relation to five different stages of oogenesis (previtellogenesis, beginning of the vitellogenesis, vitellogenesis--early choriogenesis, vitellogenesis--middle choriogenesis, late choriogenesis). In the midgut epithelium cells, the gradual accumulation of glycogen granules, lipid droplets and structures of varying electron density occurs. During vitellogenesis and choriogenesis, in the cytoplasm of midgut cells we observed the increasing number of organelles which are responsible for the intensive synthesis of lipids, proteins and saccharides such as cisterns of endoplasmic reticulum and Golgi complexes. At the end of oogenesis, autophagy also intensifies in midgut epithelial cells, which is probably caused by the great amount of reserve material. Midgut epithelium of analyzed species takes part in the yolk precursor synthesis. PMID:20661605

  10. Extracellular potentials recording in intact olfactory epithelium by microelectrode array for a bioelectronic nose.

    PubMed

    Liu, Qingjun; Ye, Weiwei; Xiao, Lidan; Du, Liping; Hu, Ning; Wang, Ping

    2010-06-15

    Human beings and animals have sensitive olfactory systems that can sense and identify a variety of odors. The purpose of this study is to combine biological cells with micro-chips to establish a novel bioelectronic nose system for odor detection by electrophysiological sensing measurements of olfactory tissue. In our experiments, 36-channel microelectrode arrays (MEAs) with the diameter of 30 microm were fabricated on the glass substrate, and olfactory epithelium was stripped from rats and fixed on the surface of MEA. Electrophysiological activities of olfactory receptor neurons in intact epithelium were measured through the multi-channel recording system. The extracellular potentials of cell networks could be effectively analyzed by correlation analysis between different channels. After being stimulated by odorants, such as acetic acid and butanedione, the olfactory cells generate different firing modes. These firing characteristics can be derived by time-domain and frequency-domain analysis, and they were different from spontaneous potentials. The investigation of olfactory epithelium can provide more information of olfactory system for artificial olfaction biomimetic design.

  11. The effect of supplementing sow with bioactive substances on neonatal small intestinal epithelium.

    PubMed

    Strzałkowski, A K; Godlewski, M M; Hallay, N; Kulasek, G; Gajewski, Z; Zabielski, R

    2007-08-01

    Development of the small intestinal epithelium in early postnatal period has a significant influence on pig's survival rate and further productivity. The aim of this research was to verify whether the diet supplementation of pregnant and lactating sow with a blend of bioactive substances (flax seed, rapeseed, linden inflorescence, taurine, L-carnitine and tocopherol acetate) had an effect on the development of intestinal epithelium in their offspring. The doses of bioactive substances were calculated to meet the demands for optimal supply of the pig fetuses and newborns. Pig neonates from two groups of sows, control and supplemented, were sacrificed at the day 1, 2, 4, 7 and 14 of life. The samples taken from mid-jejunum were evaluated for mitosis (Ki67), apoptosis (active caspase 3), autophagy (MAP I LC3), and DNA damage (p53). Increase of mitotic index was noticed at day 1, 4 and 7 for supplemented group when compared to the control. Reduction of apoptotic index was observed at day 2 as compared to control. A tendency toward elevated autophagy was observed during the first 2-4 postnatal days in both groups. p53 expression was significantly lower in supplemented group as compared to control. Overall, the mitosis to programmed cell death ratio was increased and the maturation of epithelial cells quickened. We suppose that the supplementation of pregnant and lactating sow diet with bioactive substances enhanced maturation of the small intestinal epithelium in their offspring during the early postnatal period.

  12. New HPLC evidence on endogenous tauret in retina and pigment epithelium.

    PubMed

    Petrosian, A M; Haroutounian, J E; Gundersen, T E; Blomhoff, R; Fugelli, K; Kanli, H

    2000-01-01

    This investigation was improve the separation for tauret (retinylidene taurine) and to compare its content in the retina under dark and light adaptation. To prevent tauret hydrolysis, retinal samples were quickly frozen and lyophilized. Methanol extracts of dried retina and pigment epithelium from both dark- or light-adapted frogs, Rana ridibunda, were injected onto HPLC. Synthetic standard tauret appeared at 4.7 min after the solvent front. At the same time, an endogenous substance was eluted from the mixed retinal and pigment epithelial samples. The UV spectra of this endogenous compound matched with the spectra of synthetic tauret obtained under identical conditions, with lambda(max) = 446 nm at peak. We conclude that the HPLC system used permitted full separation of tauret from the methanol extracts of the retina and pigment epithelium. TLC and further HPLC analysis have shown that tauret quantities were several times higher in the retina and pigment epithelium of the frogs adapted to dark compared with those light-adapted (about 4 h under 1000 1x illumination). Tauret based vitamin A transport is probably involved in other systems as well, where along with its other known beneficial effects taurine probably is necessary to facilitate vitamin A transport.

  13. [Morpho-functional changes in small intestine epithelium of frog Rana temporaria during hibernation].

    PubMed

    Seliverstova, E V; Prutskova, N P

    2012-01-01

    Structure and function of small intestinal epithelium were studied in overwintering frogs Rana temporaria at various stages of hibernation. In the process of testing of absorption of arginine vasotocin (AVT) in experiments in vitro it is established that at the period of hibernation there is preserved the capability of the epithelium for absorption of this nonapeptide without hydrolysis. However, as compared with October-December, in January-February and later, a decrease of the AVT absorption takes place, which is the most pronounced in March-April. Changes in epithelial structures appear by the middle of winter and are progressing by spring. In April-May, as compared with the beginning of hibernation, the height of enterocytes, the length of microvilli, and the number of microvilli decrease by 33 %, 40 %, and 57 %, respectively. The absence of features of destruction indicates an adaptive character of the observed changes. Dynamics of the studied parameters indicates morphological plasticity of the small intestine epithelium of R. temporaria at the period of hibernation.

  14. Cannabinoid receptor signaling induces proliferation but not neurogenesis in the mouse olfactory epithelium.

    PubMed

    Hutch, Chelsea R; Hegg, Colleen C

    2016-01-01

    The olfactory epithelium actively generates neurons through adulthood, and this neurogenesis is tightly regulated by multiple factors that are not fully defined. Here, we examined the role of cannabinoids in the regulation of neurogenesis in the mouse olfactory epithelium. In vivo proliferation and cell lineage studies were performed in mice (C57BL/6 and cannabinoid type 1 and 2 receptor deficient strains) treated with cannabinoids directly (WIN 55,212-2 or 2-arachidonylglycerol ether) or indirectly via inhibition of cannabinoid hydrolytic enzymes. Cannabinoids increased proliferation in neonatal and adult mice, and had no effect on proliferation in cannabinoid type 1 and 2 receptor deficient adult mice. Pretreatment with the cannabinoid type1 receptor antagonist AM251 decreased cannabinoid-induced proliferation in adult mice. Despite a cannabinoid-induced increase in proliferation, there was no change in newly generated neurons or non-neuronal cells 16 d post-treatment. However, cannabinoid administration increased apoptotic cell death at 72 hours post-treatment and by 16 d the level of apoptosis dropped to control levels. Thus, cannabinoids induce proliferation, but do not induce neurogenesis nor non-neuronal cell generation. Cannabinoid receptor signaling may regulate the balance of progenitor cell survival and proliferation in adult mouse olfactory epithelium. PMID:27606334

  15. Imaging living hair cells within the cochlear epithelium of mice using two-photon microscopy

    NASA Astrophysics Data System (ADS)

    Yuan, Tao; Gao, Simon S.; Saggau, Peter; Oghalai, John S.

    2009-02-01

    Mice are an excellent model for studying mammalian hearing and transgenic mouse models of human hearing loss are commonly available for research. However, the mouse cochlea is substantially smaller than other animal models routinely used to study cochlear physiology. This makes the study of their hair cells difficult. We developed a novel methodology to optically image calcium within living hair cells left undisturbed within the excised mouse cochlea. Fresh cochleae were harvested, left intact within their otic capsule bone, and glued upright in a recording chamber. The bone overlying the region of the cochlear epithelium to be studied was opened and Reissner's membrane was incised. A fluorescent indicator was applied to the preparation to image intracellular calcium. A custom-built upright two-photon microscope was used to image the preparation using three dimensional scanning. We were able to image about 1/3 of a cochlear turn simultaneously, in either the apical or basal regions. Within one hour of animal sacrifice, we found that outer hair cells demonstrated increased fluorescence compared with surrounding supporting cells. Thus, this methodology can be used to visualize hair cell calcium changes and mechanotransduction over a region of the epithelium. Because the epithelium is left within the cochlea, dissection trauma is minimized and artifactual changes in hair cell physiology are reduced.

  16. The midgut epithelium of aquatic arthropods: a critical target organ in environmental toxicology.

    PubMed Central

    Beaty, Barry J; Mackie, Ryan S; Mattingly, Kimberly S; Carlson, Jonathan O; Rayms-Keller, Alfredo

    2002-01-01

    The midgut epithelium of aquatic arthropods is emerging as an important and toxicologically relevant organ system for monitoring environmental pollution. The peritrophic matrix of aquatic arthropods, which is secreted by the midgut epithelium cells, is perturbed by copper or cadmium. Molecular biological studies have identified and characterized two midgut genes induced by heavy metals in the midgut epithelium. Many other metal-responsive genes (MRGs) await characterization. One of the MRGs codes for an intestinal mucin, which is critical for protecting the midgut from toxins and pathogens. Another codes for a tubulin gene, which is critical for structure and function of the midgut epithelial cells. Perturbation of expression of either gene could condition aquatic arthropod survivorship. Induction of these MRGs is a more sensitive and rapid indicator of heavy-metal pollution than biological assays. Characterization of genes induced by pollutants could provide mechanistic understanding of fundamental cellular responses to pollutants and insight into determinants of aquatic arthropod population genetic structure and survivorship in nature. PMID:12634118

  17. Cells and Culture Systems Used to Model the Small Airway Epithelium.

    PubMed

    Bhowmick, Rudra; Gappa-Fahlenkamp, Heather

    2016-06-01

    The pulmonary epithelium is divided into upper, lower, and alveolar (or small) airway epithelia and acts as the mechanical and immunological barrier between the external environment and the underlying submucosa. Of these, the small airway epithelium is the principal area of gas exchange and has high immunological activity, making it a major area of cell biology, immunology, and pharmaceutical research. As animal models do not faithfully represent the human pulmonary system and ex vivo human lung samples have reliability and availability issues, cell lines, and primary cells are widely used as small airway epithelial models. In vitro, these cells are mostly cultured as monolayers (2-dimensional cultures), either media submerged or at air-liquid interface. However, these 2-dimensional cultures lack a three dimension-a scaffolding extracellular matrix, which establishes the intercellular network in the in vivo airway epithelium. Therefore, 3-dimensional cell culture is currently a major area of development, where cells are cultured in a matrix or are cultured in a manner that they develop ECM-like scaffolds between them, thus mimicking the in vivo phenotype more faithfully. This review focuses on the commonly used small airway epithelial cells, their 2-dimensional and 3-dimensional culture techniques, and their comparative phenotype when cultured under these systems. PMID:27071933

  18. HMGA1 drives metabolic reprogramming of intestinal epithelium during hyperproliferation, polyposis, and colorectal carcinogenesis.

    PubMed

    Williams, Michael D; Zhang, Xing; Belton, Amy S; Xian, Lingling; Huso, Tait; Park, Jeong-Jin; Siems, William F; Gang, David R; Resar, Linda M S; Reeves, Raymond; Hill, Herbert H

    2015-03-01

    Although significant progress has been made in the diagnosis and treatment of colorectal cancer (CRC), it remains a leading cause of cancer death worldwide. Early identification and removal of polyps that may progress to overt CRC is the cornerstone of CRC prevention. Expression of the High Mobility Group A1 (HMGA1) gene is significantly elevated in CRCs as compared with adjacent, nonmalignant tissues. We investigated metabolic aberrations induced by HMGA1 overexpression in small intestinal and colonic epithelium using traveling wave ion mobility mass spectrometry (TWIMMS) in a transgenic model in which murine Hmga1 was misexpressed in colonic epithelium. To determine if these Hmga1-induced metabolic alterations in mice were relevant to human colorectal carcinogenesis, we also investigated tumors from patients with CRC and matched, adjacent, nonmalignant tissues. Multivariate statistical methods and manual comparisons were used to identify metabolites specific to Hmga1 and CRC. Statistical modeling of data revealed distinct metabolic patterns in Hmga1 transgenics and human CRC samples as compared with the control tissues. We discovered that 13 metabolites were specific for Hmga1 in murine intestinal epithelium and also found in human CRC. Several of these metabolites function in fatty acid metabolism and membrane composition. Although further validation is needed, our results suggest that high levels of HMGA1 protein drive metabolic alterations that contribute to CRC pathogenesis through fatty acid synthesis. These metabolites could serve as potential biomarkers or therapeutic targets.

  19. Heterotopic transplantation of glycerin-preserved trachea: effect of respiratory epithelium desquamation on acute rejection.

    PubMed

    Saueressig, M G; Edelweiss, M I A; Souza, F H; Moreschi, A H; Savegnago, F L; Macedo Neto, A V

    2005-07-01

    An effective preservation method and decreased rejection are essential for tracheal transplantation in the reconstruction of large airway defects. Our objective in the present study was to evaluate the antigenic properties of glycerin-preserved tracheal segments. Sixty-one tracheal segments (2.4 to 3.1 cm) were divided into three groups: autograft (N = 21), fresh allograft (N = 18) and glycerin-preserved allograft (N = 22). Two segments from different groups were implanted into the greater omentum of dogs (N = 31). After 28 days, the segments were harvested and analyzed for mononuclear infiltration score and for the presence of respiratory epithelium. The fresh allograft group presented the highest score for mononuclear infiltration (1.78 +/- 0.43, P < or = 0.001) when compared to the autograft and glycerin-preserved allograft groups. In contrast to the regenerated epithelium observed in autograft segments, all fresh allografts and glycerin-preserved allografts had desquamation of the respiratory mucosa. The low antigenicity observed in glycerin segments was probably the result of denudation of the respiratory epithelium and perhaps due to the decrease of major histocompatibility complex class II antigens.

  20. Neuropilin 1 Receptor Is Up-Regulated in Dysplastic Epithelium and Oral Squamous Cell Carcinoma.

    PubMed

    Shahrabi-Farahani, Shokoufeh; Gallottini, Marina; Martins, Fabiana; Li, Erik; Mudge, Dayna R; Nakayama, Hironao; Hida, Kyoko; Panigrahy, Dipak; D'Amore, Patricia A; Bielenberg, Diane R

    2016-04-01

    Neuropilins are receptors for disparate ligands, including proangiogenic factors such as vascular endothelial growth factor and inhibitory class 3 semaphorin (SEMA3) family members. Differentiated cells in skin epithelium and cutaneous squamous cell carcinoma highly express the neuropilin-1 (NRP1) receptor. We examined the expression of NRP1 in human and mouse oral mucosa. NRP1 was significantly up-regulated in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). NRP1 receptor localized to the outer suprabasal epithelial layers in normal tongue, an expression pattern similar to the normal skin epidermis. However, dysplastic tongue epithelium and OSCC up-regulated NRP1 in basal and proliferating epithelial layers, a profile unseen in cutaneous squamous cell carcinoma. NRP1 up-regulation is observed in a mouse carcinogen-induced OSCC model and in human tongue OSCC biopsies. Human OSCC cell lines express NRP1 protein in vitro and in mouse tongue xenografts. Sites of capillary infiltration into orthotopic OSCC tumors correlate with high NRP1 expression. HSC3 xenografts, which express the highest NRP1 levels of the cell lines examined, showed massive intratumoral lymphangiogenesis. SEMA3A inhibited OSCC cell migration, suggesting that the NRP1 receptor was bioactive in OSCC. In conclusion, NRP1 is regulated in the oral epithelium and is selectively up-regulated during epithelial dysplasia. NRP1 may function as a reservoir to sequester proangiogenic ligands within the neoplastic compartment, thereby recruiting neovessels toward tumor cells. PMID:26877262

  1. Localisation of luminal epithelium edge in digital histopathology images of IHC stained slides of endometrial biopsies.

    PubMed

    Li, Guannan; Sanchez, Victor; Patel, Gnyaneshwari; Quenby, Siobhan; Rajpoot, Nasir

    2015-06-01

    Diagnosis of recurrent miscarriage due to abnormally high number of uterine natural killer (uNK) cells has recently been made possible by a protocol devised by Quenby et al. Hum Reprod 2009;24(1):45-54. The diagnosis involves detection and counting of stromal and uNK cell nuclei in endometrial biopsy slides immunohistochemically stained with haematoxylin for staining cell nuclei and CD56 as a marker for the uNK cells. However, manual diagnosis is a laborious process, fraught with subjective errors. In this paper, we present a novel method for detection of uterine natural killer (uNK) cells in the human female uterus lining and localisation of the luminal epithelium edge in endometrial biopsies. Specifically, we employ a local phase symmetry based method to detect stromal cell nuclei and propose an adaptive background removal method that significantly eases the segmentation of uNK cell nuclei regions. We also propose a novel method using alpha shapes for the identification of epithelial cell nuclei and B-Spline curve fitting on identified cell nuclei to localise the luminal epithelium edge. The objective of edge localisation is to avoid cell nuclei near the luminal epithelium edge being counted in the diagnosis process due to their non-relevance to the calculation of stromal to uNK cell ratio that determines the diagnosis of recurrent miscarriages in the end. The resulting algorithm offers a promising potential for computer-assisted diagnosis of recurrent miscarriage due to its high accuracy.

  2. Ex vivo generation of a functional and regenerative wound epithelium from axolotl (Ambystoma mexicanum) skin.

    PubMed

    Ferris, Donald R; Satoh, Akira; Mandefro, Berhan; Cummings, Gillian M; Gardiner, David M; Rugg, Elizabeth L

    2010-10-01

    Urodele amphibians (salamanders) are unique among adult vertebrates in their ability to regenerate structurally complete and fully functional limbs. Regeneration is a stepwise process that requires interactions between keratinocytes, nerves and fibroblasts. The formation of a wound epithelium covering the amputation site is an early and necessary event in the process but the molecular mechanisms that underlie the role of the wound epithelium in regeneration remain unclear. We have developed an ex vivo model that recapitulates many features of in vivo wound healing. The model comprises a circular explant of axolotl (Ambystoma mexicanum) limb skin with a central circular, full thickness wound. Re-epithelialization of the wound area is rapid (typically <11 h) and is dependent on metalloproteinase activity. The ex vivo wound epithelium is viable, responds to neuronal signals and is able to participate in ectopic blastema formation and limb regeneration. This ex vivo model provides a reproducible and tractable system in which to study the cellular and molecular events that underlie wound healing and regeneration.

  3. Biosensor analysis of natural and artificial sweeteners in intact taste epithelium.

    PubMed

    Zhang, Fenni; Zhang, Qian; Zhang, Diming; Lu, Yanli; Liu, Qingjun; Wang, Ping

    2014-04-15

    Sweeteners are commonly used as food additives in our daily life, which, however, have been causing a number of undesirable diseases since the last century. Therefore, the detection and quantification of sweeteners are of great value for food safety. In this study, we used a taste biosensor to measure and analyze different sweeteners, both natural and artificial sweeteners included. Electrophysiological activities from taste epithelium were detected by the multi-channel biosensors and analyzed with spatiotemporal methods. The longtime signal result showed different temporal-frequency properties with stimulations of individual sweeteners such as glucose, sucrose, saccharin, and cyclamate, while the multi-channel results in our study revealed the spatial expression of taste epithelium to sweet stimuli. Furthermore, in the analysis of sweetener with different concentrations, the result showed obvious dose-dependent increases in signal responses of the taste epithelium, which indicated promising applications in sweetness evaluation. Besides, the mixture experiment of two natural sweeteners with a similar functional unit (glucose and sucrose) presented two signal patterns, which turned out to be similar with responses of each individual stimulus involved. The biosensor analysis of common sweeteners provided new approaches for both natural and artificial sweeteners evaluation. PMID:24292144

  4. Ultra structural study of the rat cheek epithelium treated with Neem extract.

    PubMed

    Azmi, Muhammad Arshad; Khatoon, Nasira; Ghaffar, Rizwana Abdul

    2015-11-01

    The purpose of this study was to investigate the effects of neem extract (Azadirachta indica A. Juss) on the ultrastructure of the rat oral epithelium, because neem extract has been added in the tooth paste as an anti-plaque-forming substance in Asian countries. The non-toxic dose of 2000 mg/kg body weight of Neem extract (NBE) was applied daily to the surface of buccal epithelium for four weeks and controls did not receive Neem extract. After four weeks cheek epithelial tissues were excised and processed for light microscopy, scanning and transmission electron microscopy. Light microscopy did not show significant differences between NBE-treated and control epithelium. Difference between control and treated rats weight was non-significant. Moreover, time period was also non-significant. Irregular cell surfaces were noticed when compared to control specimens when examined by scanning electron microscopy. Under transmission electron microscopy, wider intercellular spaces were observed in the treated epithelial spinous cellular layers when compared to control. Further, more keratohyalin granules were present in experimental granular cells. It was concluded that present study showed differences between Neem-treated and control in epithelial tissues but these structural differences may not be related to adverse side effects of the Neem extract.

  5. Effects of irradiation on canine tracheal epithelium: a physiological and morphological correlate

    SciTech Connect

    Man, S.F.; Logus, J.W.; Mok, K.; Yamamoto, H.; Ahmed, I.H.; Man, G.C.; Hulbert, W.C.

    1987-01-01

    We delivered 20 Gy irradiation in one fraction to a 6 cm segment of trachea in 11 dogs. Tracheal mucous transport was studied before and whenever possible at weekly intervals after irradiation using a gamma camera system and /sup 99m/technetium labeled sulfur colloid. Ten of the eleven animals were sacrificed at three different time intervals (1-2, 15-16 and 30-34 weeks) post-irradiation, and the tracheal epithelium removed for studies using Ussing chambers followed by preparation for microscopic analysis. Mucous transport along the length of the trachea was normal before irradiation, but following irradiation it became abnormal in the irradiated zone. Compared to the epithelium from the cranial and caudal segments, the irradiated epithelium had similar bioelectric measurements (potential difference, short-circuit current and resistance) and mannitol permeability. Also, the changes in the bioelectric measurements following indomethacin (10(-6) M) and epinephrine (10(-6) M) used sequentially, were similar in both the control and irradiated tissues. Scanning electron microscopic analysis of the irradiated zone revealed patches of nonciliated epithelial cells among the ciliates. We conclude that irradiation caused a persistent replacement of ciliated cells with nonciliates throughout the entire study period and that this alteration impaired mucous transport but did not affect epithelial ion secretion or barrier function.

  6. Galactomannan and Zymosan Block the Epinephrine-Induced Particle Transport in Tracheal Epithelium

    PubMed Central

    Weiterer, Sebastian; Kohlen, Thomas; Veit, Florian; Sachs, Lydia; Uhle, Florian; Lichtenstern, Christoph; Weigand, Markus A.; Henrich, Michael

    2015-01-01

    Background Ciliary beating by respiratory epithelial cells continuously purges pathogens from the lower airways. Here we investigated the effect of the fungal cell wall polysaccharides Galactomannan (GM) and Zymosan (Zym) on the adrenergic activated particle transport velocity (PTV) of tracheal epithelium. Methods Experiments were performed using tracheae isolated from male C57BL/6J mice. Transport velocity of the cilia bearing epithelial cells was measured by analysing recorded image sequences. Generation of reactive oxygen species (ROS) were determined using Amplex Red reagents. PCR experiments were performed on isolated tracheal epithelium to identify adrenergic receptor mRNA. Results The adrenergic receptors α1D, α2A, β1 and β2 have been identified in isolated tracheal epithelium. We found epinephrine responsible for an increase in PTV, which could only be reduced by selective β-receptor-inhibition. In addition, either GM or Zym prevented the epinephrine induced PTV increase. Furthermore, we observed a strong ROS generation evoked by GM or Zym. However, epinephrine induced increase in PTV recovered in the presence of GM and Zym after application of ROS scavengers. Conclusion Both GM or Zym trigger reversible ROS generation in tracheal tissue leading to inhibition of the β-adrenergic increase in PTV. PMID:26571499

  7. Epithelium-generated neuropeptide Y induces smooth muscle contraction to promote airway hyperresponsiveness

    PubMed Central

    Li, Shanru; Koziol-White, Cynthia; Jude, Joseph; Jiang, Meiqi; Zhao, Hengjiang; Cao, Gaoyuan; Yoo, Edwin; Jester, William; Morley, Michael P.; Zhou, Su; Wang, Yi; Lu, Min Min; Panettieri, Reynold A.

    2016-01-01

    Asthma is one of the most common chronic diseases globally and can be divided into presenting with or without an immune response. Current therapies have little effect on nonimmune disease, and the mechanisms that drive this type of asthma are poorly understood. Here, we have shown that loss of the transcription factors forkhead box P1 (Foxp1) and Foxp4, which are critical for lung epithelial development, in the adult airway epithelium evokes a non-Th2 asthma phenotype that is characterized by airway hyperresponsiveness (AHR) without eosinophilic inflammation. Transcriptome analysis revealed that loss of Foxp1 and Foxp4 expression induces ectopic expression of neuropeptide Y (Npy), which has been reported to be present in the airways of asthma patients, but whose importance in disease pathogenesis remains unclear. Treatment of human lung airway explants with recombinant NPY increased airway contractility. Conversely, loss of Npy in Foxp1- and Foxp4-mutant airway epithelium rescued the AHR phenotype. We determined that NPY promotes AHR through the induction of Rho kinase activity and phosphorylation of myosin light chain, which induces airway smooth muscle contraction. Together, these studies highlight the importance of paracrine signals from the airway epithelium to the underlying smooth muscle to induce AHR and suggest that therapies targeting epithelial induction of this phenotype may prove useful in treatment of noneosinophilic asthma. PMID:27088802

  8. The tumor suppressor PTEN and the PDK1 kinase regulate formation of the columnar neural epithelium

    PubMed Central

    Grego-Bessa, Joaquim; Bloomekatz, Joshua; Castel, Pau; Omelchenko, Tatiana; Baselga, José; Anderson, Kathryn V

    2016-01-01

    Epithelial morphogenesis and stability are essential for normal development and organ homeostasis. The mouse neural plate is a cuboidal epithelium that remodels into a columnar pseudostratified epithelium over the course of 24 hr. Here we show that the transition to a columnar epithelium fails in mutant embryos that lack the tumor suppressor PTEN, although proliferation, patterning and apical-basal polarity markers are normal in the mutants. The Pten phenotype is mimicked by constitutive activation of PI3 kinase and is rescued by the removal of PDK1 (PDPK1), but does not depend on the downstream kinases AKT and mTORC1. High resolution imaging shows that PTEN is required for stabilization of planar cell packing in the neural plate and for the formation of stable apical-basal microtubule arrays. The data suggest that appropriate levels of membrane-associated PDPK1 are required for stabilization of apical junctions, which promotes cell elongation, during epithelial morphogenesis. DOI: http://dx.doi.org/10.7554/eLife.12034.001 PMID:26809587

  9. The kinetic behaviour of the cranial neural epithelium during neurulation in the rat.

    PubMed

    Tuckett, F; Morriss-Kay, G M

    1985-02-01

    The kinetic behaviour of the cranial neuroepithelial cells of rat embryos during neurulation is described. Serial transverse sections of 4-, 8-, 12- and 16-somite-stage embryos show that differential mitosis does not play a part in the mechanisms responsible for effecting cranial neural tube closure. A constant cell number is found in the midbrain/hindbrain neural epithelium during all four stages; the mitotic spindle axes are oriented parallel to the long axis of the embryo, so that increase in cell number occurs in this direction only. Growth is only expressed by an expansion in the volume of the forebrain, which projects rostral to the notochordal tip. [3H]thymidine studies (using an in vitro culture technique) show no significant variation in the cell cycle time between the forebrain and the midbrain/anterior hindbrain neural epithelium. It is suggested that the neural epithelium is a fluid structure whose overall shape is strictly controlled while the cells within it flow towards and into the rapidly expanding forebrain. PMID:3989446

  10. Inhibition of Pasteurella multocida Adhesion to Rabbit Respiratory Epithelium Using Lectins

    PubMed Central

    Carrillo, Magda Patricia; Martinez, Nhora María; Patiño, María del Pilar; Iregui, Carlos Arturo

    2015-01-01

    This study aimed to evaluate the ability of a panel of lectins to inhibit the ability of Pasteurella multocida to adhere to and affect the rabbit respiratory epithelium. Nasal septa from rabbit fetuses were cultured with various lectins before the addition of P. multocida. The percentage of bacteria adhering to the epithelium was evaluated semiquantitatively by indirect immunoperoxidase (IIP) staining. The goblet cells (GCs) were counted in semithin sections stained with toluidine blue and served as the main morphological criterion to evaluate the inhibitory effect of the lectins. The lectins PNA, WGA, RCA120, and DBA significantly inhibited the adhesion of P. multocida to the ciliated epithelium (P < 0.05) and prevented the pathogen-induced increase in the number of GCs (P < 0.05) compared with those of positive control tissues. In addition, VVA, SJA, UEA I, DSL, SBA, and ECL significantly inhibited the increase in GCs compared with that of the control tissues. The results suggest that less aggressive therapeutic strategies, such as treatment with lectins, may represent alternative approaches to control bacterial respiratory infections. PMID:25810949

  11. DICER Regulates the Formation and Maintenance of Cell-Cell Junctions in the Mouse Seminiferous Epithelium.

    PubMed

    Korhonen, Hanna Maria; Yadav, Ram Prakash; Da Ros, Matteo; Chalmel, Frédéric; Zimmermann, Céline; Toppari, Jorma; Nef, Serge; Kotaja, Noora

    2015-12-01

    The endonuclease DICER that processes micro-RNAs and small interfering RNAs is essential for normal spermatogenesis and male fertility. We previously showed that the deletion of Dicer1 gene in postnatal spermatogonia in mice using Ngn3 promoter-driven Cre expression caused severe defects in the morphogenesis of haploid spermatid to mature spermatozoon, including problems in cell polarization and nuclear elongation. In this study, we further analyzed the same mouse model and revealed that absence of functional DICER in differentiating male germ cells induces disorganization of the cell-cell junctions in the seminiferous epithelium. We detected discontinuous and irregular apical ectoplasmic specializations between elongating spermatids and Sertoli cells. The defective anchoring of spermatids to Sertoli cells caused a premature release of spermatids into the lumen. Our findings may help also explain the abnormal elongation process of remaining spermatids because these junctions and the correct positioning of germ cells in the epithelium are critically important for the progression of spermiogenesis. Interestingly, cell adhesion-related genes were generally upregulated in Dicer1 knockout germ cells. Claudin 5 ( Cldn5 ) was among the most upregulated genes and we show that the polarized localization of CLAUDIN5 in the apical ectoplasmic specializations was lost in Dicer1 knockout spermatids. Our results suggest that DICER-dependent pathways control the formation and organization of cell-cell junctions in the seminiferous epithelium via the regulation of cell adhesion-related genes. PMID:26510868

  12. Ultrastructural observations of the testicular epithelium and spermatozoa of Pseudochordodes bedriagae (Gordiida, Nematomorpha).

    PubMed

    De Villalobos, Cristina; Restelli, Mario; Schmidt-Rhaesa, Andreas; Zanca, Fernanda

    2005-08-01

    Two questions are of interest concerning the male reproductive system in Gordiida: (1) is the epithelium surrounding the testis continuous or discontinuous and (2) is the type of spermatozoon as described at the transmission electron-microscopical level for the two species of Gordius typical for all Gordiida? An examination of the South American species Pseudochordodes bedriagae has allowed us to add new information to this poorly studied phylum. Testicular tubes are large, filled with spermatozoa, and surrounded by a continuous epithelium. The epithelial cells that line the posterior testes occasionally overlap, and their cytoplasm is narrow and contains dense granules, abundant endoplasmic reticulum, and vesicles. The plasma membrane possesses microvilli with many filaments. This epithelium rests on a basement membrane. The spermatozoa in P. bedriagae resemble the known spermatozoa of two Gordius species but differ in presenting a uniform halo layer of less dense chromatin that surrounds the dense chromatin in the nucleus. The finding that a similar type of spermatozoa occurs in both genera (Pseudochordodes and Gordius) makes it likely that it is present in all other Gordiida and is therefore an autapomorphy of the Gordiida.

  13. Surface to nuclear distances in human bronchial epithelium: Relationships to penetration by Rn daughters

    SciTech Connect

    Baldwin, F.; Hovey, A.; McEwen, T.; O'Connor, R.; Unruh, H.; Bowden, D.H. )

    1991-02-01

    Lung cancer in U miners is thought to be related to the inhalation of particulate Rn daughters. Since the depth of penetration by alpha particles is short, the thickness of the epithelium lining the bronchial tree may be a critical factor in the development of cancers at specific sites in the lung. The objectives of the study were to measure the thickness of the epithelium at all levels of the human bronchial tree, to determine the distances of epithelial nuclei from the mucociliary surface, and to compare these parameters in smokers and nonsmokers. Twenty-nine surgically removed specimens were examined; 26 were from smokers. No significant differences were found between smokers and nonsmokers, allowing us to treat the 29 cases as a homogeneous group. With progressive divisions of the bronchi, the epithelium decreases in thickness, and distances of nuclei from the surface are also less in the peripheral bronchi. Allowing for artefacts of tissue preparation, the mean distance from the mucociliary surface to the underlying nuclei varies between 17 and 38 microns.

  14. Ovarian surface epithelium at the junction area contains a cancer-prone stem cell niche.

    PubMed

    Flesken-Nikitin, Andrea; Hwang, Chang-Il; Cheng, Chieh-Yang; Michurina, Tatyana V; Enikolopov, Grigori; Nikitin, Alexander Yu

    2013-03-14

    Epithelial ovarian cancer (EOC) is the fifth leading cause of cancer deaths among women in the United States, but its pathogenesis is poorly understood. Some epithelial cancers are known to occur in transitional zones between two types of epithelium, whereas others have been shown to originate in epithelial tissue stem cells. The stem cell niche of the ovarian surface epithelium (OSE), which is ruptured and regenerates during ovulation, has not yet been defined unequivocally. Here we identify the hilum region of the mouse ovary, the transitional (or junction) area between the OSE, mesothelium and tubal (oviductal) epithelium, as a previously unrecognized stem cell niche of the OSE. We find that cells of the hilum OSE are cycling slowly and express stem and/or progenitor cell markers ALDH1, LGR5, LEF1, CD133 and CK6B. These cells display long-term stem cell properties ex vivo and in vivo, as shown by our serial sphere generation and long-term lineage-tracing assays. Importantly, the hilum cells show increased transformation potential after inactivation of tumour suppressor genes Trp53 and Rb1, whose pathways are altered frequently in the most aggressive and common type of human EOC, high-grade serous adenocarcinoma. Our study supports experimentally the idea that susceptibility of transitional zones to malignant transformation may be explained by the presence of stem cell niches in those areas. Identification of a stem cell niche for the OSE may have important implications for understanding EOC pathogenesis.

  15. Annexin A2 Acts as an Adhesion Molecule on the Endometrial Epithelium during Implantation in Mice

    PubMed Central

    Lee, Kai-Fai; Chiu, Philip C. N.; Pang, Ronald T. K.; Ng, Ernest H. Y.; Yeung, William S. B.

    2015-01-01

    To determine the function of Annexin A2 (Axna2) in mouse embryo implantation in vivo, experimental manipulation of Axna2 activities was performed in mouse endometrial tissue in vivo and in vitro. Histological examination of endometrial tissues was performed throughout the reproduction cycle and after steroid treatment. Embryo implantation was determined after blockage of the Axna2 activities by siRNA or anti-Axna2 antibody. The expression of Axna2 immunoreactivies in the endometrial luminal epithelium changed cyclically in the estrus cycle and was upregulated by estrogen. After nidatory estrogen surge, there was a concentration of Axna2 immunoreactivities at the interface between the implanting embryo and the luminal epithelium. The phenomenon was likely to be induced by the implanting embryos as no such concentration of signal was observed in the inter-implantation sites and in pseudopregnancy. Knockdown of Axna2 by siRNA reduced attachment of mouse blastocysts onto endometrial tissues in vitro. Consistently, the number of implantation sites was significantly reduced after infusion of anti-Axna2 antibody into the uterine cavity. Steroids and embryos modulate the expression of Axna2 in the endometrial epithelium. Axna2 may function as an adhesion molecule during embryo implantation in mice. PMID:26444699

  16. Annexin A2 Acts as an Adhesion Molecule on the Endometrial Epithelium during Implantation in Mice.

    PubMed

    Wang, Bing; Ye, Tian-Min; Lee, Kai-Fai; Chiu, Philip C N; Pang, Ronald T K; Ng, Ernest H Y; Yeung, William S B

    2015-01-01

    To determine the function of Annexin A2 (Axna2) in mouse embryo implantation in vivo, experimental manipulation of Axna2 activities was performed in mouse endometrial tissue in vivo and in vitro. Histological examination of endometrial tissues was performed throughout the reproduction cycle and after steroid treatment. Embryo implantation was determined after blockage of the Axna2 activities by siRNA or anti-Axna2 antibody. The expression of Axna2 immunoreactivies in the endometrial luminal epithelium changed cyclically in the estrus cycle and was upregulated by estrogen. After nidatory estrogen surge, there was a concentration of Axna2 immunoreactivities at the interface between the implanting embryo and the luminal epithelium. The phenomenon was likely to be induced by the implanting embryos as no such concentration of signal was observed in the inter-implantation sites and in pseudopregnancy. Knockdown of Axna2 by siRNA reduced attachment of mouse blastocysts onto endometrial tissues in vitro. Consistently, the number of implantation sites was significantly reduced after infusion of anti-Axna2 antibody into the uterine cavity. Steroids and embryos modulate the expression of Axna2 in the endometrial epithelium. Axna2 may function as an adhesion molecule during embryo implantation in mice.

  17. Nicotine modulates gelatinase B (MMP-9) and epilysin (MMP-28) expression in reconstituted human oral epithelium.

    PubMed

    Renò, Filippo; Rocchetti, Vincenzo; Migliario, Mario; Cannas, Mario

    2011-01-01

    Oral epithelial keratinocytes express nicotinic cholinergic receptors which activation modulates keratinocytes differentiation and migration through different metabolic pathways. Matrix metalloproteinases (MMPs) are Zn-dependent enzyme involved in cell migration. Among them, gelatinase B (MMP-9) and epilysin (MMP-28) are two MMPs expressed by human keratinocytes during both wound healing and proliferation. Their expression has been investigated in a reconstituted human oral epithelium (HOE) exposed to nicotine (Nic, 1-50 μM) for 72 h both in the absence and presence of the nicotinic antagonist mecamylamine (Mec), H7, a PKC inhibitor and PD98059, a MAPK inhibitor (PD). At the end of treatment, MMP-28 expression has been analyzed in epithelium sections using an anti-MMP-28 antibody, whereas MMP-9 presence and activity has been measured in cell-conditioned medium analyzed by gelatine zymography. The expression of MMP-9 was reduced by Nic in a dose-dependent fashion and this effect was antagonized by Mec, H7 and PD. On the other hand, Nic increased the expression of MMP-28, and this effect was blocked both by H7 and PD, whereas Mec even enforced it. Nic effects on MMP-9 and MMP-28 expression by oral keratinocytes were not previously reported and these data suggest MMPs expression mediated by PKC and MAPK as a possible target for Nic toxicity in oral epithelium.

  18. Death in the intestinal epithelium-basic biology and implications for inflammatory bowel disease.

    PubMed

    Blander, J Magarian

    2016-07-01

    Every 4-5 days, intestinal epithelial cells (IEC) are terminated as they reach the end of their life. This process ensures that the epithelium is comprised of the fittest cells that maintain an impermeable barrier to luminal contents and the gut microbiota, as well as the most metabolically able cells that conduct functions in nutrient absorption, digestion, and secretion of antimicrobial peptides. IEC are terminated by apical extrusion-or shedding-from the intestinal epithelial monolayer into the gut lumen. Whether death by apoptosis signals extrusion or death follows expulsion by younger IEC has been a matter of debate. Seemingly a minor detail, IEC death before or after apical extrusion bears weight on the potential contribution of apoptotic IEC to intestinal homeostasis as a consequence of their recognition by intestinal lamina propria phagocytes. In inflammatory bowel disease (IBD), excessive death is observed in the ileal and colonic epithelium. The precise mode of IEC death in IBD is not defined. A highly inflammatory milieu within the intestinal lamina propria, rich in the proinflammatory cytokine, TNF-α, increases IEC shedding and compromises barrier integrity fueling more inflammation. A milestone in the treatment of IBD, anti-TNF-α therapy, may promote mucosal healing by reversing increased and inflammation-associated IEC death. Understanding the biology and consequences of cell death in the intestinal epithelium is critical to the design of new avenues for IBD therapy. PMID:27250564

  19. Ultrastructural changes of the midgut epithelium in Isohypsibius granulifer granulifer Thulin, 1928 (Tardigrada: Eutardigrada) during oogenesis.

    PubMed

    Rost-Roszkowska, Magdalena M; Poprawa, Izabela; Wójtowicz, Maria; Kaczmarek, Lukasz

    2011-04-01

    The midgut epithelium of Isohypsibius granulifer granulifer (Eutardigrada) is composed of columnar digestive cells. At its anterior end, a group of cells with cytoplasm which differs from the cytoplasm of digestive cells is present. Probably, those cells respond to crescent-like cells (midgut regenerative cells) described for some tardigrade species. Their mitotic divisions have not been observed. We analyzed the ultrastructure of midgut digestive cells in relation to five different stages of oogenesis (previtellogenesis, beginning of the vitellogenesis, vitellogenesis--early choriogenesis, vitellogenesis--middle choriogenesis, late choriogenesis). In the midgut epithelium cells, the gradual accumulation of glycogen granules, lipid droplets and structures of varying electron density occurs. During vitellogenesis and choriogenesis, in the cytoplasm of midgut cells we observed the increasing number of organelles which are responsible for the intensive synthesis of lipids, proteins and saccharides such as cisterns of endoplasmic reticulum and Golgi complexes. At the end of oogenesis, autophagy also intensifies in midgut epithelial cells, which is probably caused by the great amount of reserve material. Midgut epithelium of analyzed species takes part in the yolk precursor synthesis.

  20. Lactobacillus reuteri Inhibition of Enteropathogenic Escherichia coli Adherence to Human Intestinal Epithelium.

    PubMed

    Walsham, Alistair D S; MacKenzie, Donald A; Cook, Vivienne; Wemyss-Holden, Simon; Hews, Claire L; Juge, Nathalie; Schüller, Stephanie

    2016-01-01

    Enteropathogenic Escherichia coli (EPEC) is a major cause of diarrheal infant death in developing countries, and probiotic bacteria have been shown to provide health benefits in gastrointestinal infections. In this study, we have investigated the influence of the gut symbiont Lactobacillus reuteri on EPEC adherence to the human intestinal epithelium. Different host cell model systems including non-mucus-producing HT-29 and mucus-producing LS174T intestinal epithelial cell lines as well as human small intestinal biopsies were used. Adherence of L. reuteri to HT-29 cells was strain-specific, and the mucus-binding proteins CmbA and MUB increased binding to both HT-29 and LS174T cells. L. reuteri ATCC PTA 6475 and ATCC 53608 significantly inhibited EPEC binding to HT-29 but not LS174T cells. While pre-incubation of LS174T cells with ATCC PTA 6475 did not affect EPEC attaching/effacing (A/E) lesion formation, it increased the size of EPEC microcolonies. ATCC PTA 6475 and ATCC 53608 binding to the mucus layer resulted in decreased EPEC adherence to small intestinal biopsy epithelium. Our findings show that L. reuteri reduction of EPEC adhesion is strain-specific and has the potential to target either the epithelium or the mucus layer, providing further rationale for the selection of probiotic strains. PMID:26973622

  1. Biosensor analysis of natural and artificial sweeteners in intact taste epithelium.

    PubMed

    Zhang, Fenni; Zhang, Qian; Zhang, Diming; Lu, Yanli; Liu, Qingjun; Wang, Ping

    2014-04-15

    Sweeteners are commonly used as food additives in our daily life, which, however, have been causing a number of undesirable diseases since the last century. Therefore, the detection and quantification of sweeteners are of great value for food safety. In this study, we used a taste biosensor to measure and analyze different sweeteners, both natural and artificial sweeteners included. Electrophysiological activities from taste epithelium were detected by the multi-channel biosensors and analyzed with spatiotemporal methods. The longtime signal result showed different temporal-frequency properties with stimulations of individual sweeteners such as glucose, sucrose, saccharin, and cyclamate, while the multi-channel results in our study revealed the spatial expression of taste epithelium to sweet stimuli. Furthermore, in the analysis of sweetener with different concentrations, the result showed obvious dose-dependent increases in signal responses of the taste epithelium, which indicated promising applications in sweetness evaluation. Besides, the mixture experiment of two natural sweeteners with a similar functional unit (glucose and sucrose) presented two signal patterns, which turned out to be similar with responses of each individual stimulus involved. The biosensor analysis of common sweeteners provided new approaches for both natural and artificial sweeteners evaluation.

  2. Keratin 8 is required for the maintenance of architectural structure in thymus epithelium.

    PubMed

    Odaka, Chikako; Loranger, Anne; Takizawa, Kazuya; Ouellet, Michel; Tremblay, Michel J; Murata, Shigeo; Inoko, Akihito; Inagaki, Masaki; Marceau, Normand

    2013-01-01

    Keratins (Ks), the intermediate filament (IF) proteins of epithelia, are coordinately expressed as pairs in a cell-lineage and differentiation manner. Cortical thymic epithelial cells (cTECs) predominantly express the simple epithelium keratin 8/18 (K8/K18) pair, whereas medullary thymic epithelial cells (mTECs) express the stratified epithelium K5/K14 pair, with TECs exhibiting K5 and K8 at the cortico-medullary junction in mature thymus. In the work reported here, we used wild-type (WT) and K8-knockout (K8-null) mice to address the contribution of K8/K18 IFs in the maintenance of the thymic epithelial structure. K8-null thymus maintained the differential cell segregation at the cortex versus the medulla observed in WT thymus, and the distribution of immature thymocytes at the cortex. The K8/K18 loss did not affect thymocyte development. However, it massively perturbed the TEC morphology both at the cortex and the medulla, along with a prominent depletion of cTECs. Such tissue alterations coincided with an increase in apoptosis and a reduced expression of Albatross (Fas-binding factor-1), also known for its capacity to bind K8/18 IFs. In addition, the K8/K18 loss affected the distribution of K5/K14-positive mTECs, but not their differentiation status. Together, the results indicate that K8/K18 IFs constitute key promoters of the thymic epithelium integrity.

  3. Insect wing membrane topography is determined by the dorsal wing epithelium.

    PubMed

    Belalcazar, Andrea D; Doyle, Kristy; Hogan, Justin; Neff, David; Collier, Simon

    2013-01-01

    The Drosophila wing consists of a transparent wing membrane supported by a network of wing veins. Previously, we have shown that the wing membrane cuticle is not flat but is organized into ridges that are the equivalent of one wing epithelial cell in width and multiple cells in length. These cuticle ridges have an anteroposterior orientation in the anterior wing and a proximodistal orientation in the posterior wing. The precise topography of the wing membrane is remarkable because it is a fusion of two independent cuticle contributions from the dorsal and ventral wing epithelia. Here, through morphological and genetic studies, we show that it is the dorsal wing epithelium that determines wing membrane topography. Specifically, we find that wing hair location and membrane topography are coordinated on the dorsal, but not ventral, surface of the wing. In addition, we find that altering Frizzled Planar Cell Polarity (i.e., Fz PCP) signaling in the dorsal wing epithelium alone changes the membrane topography of both dorsal and ventral wing surfaces. We also examined the wing morphology of two model Hymenopterans, the honeybee Apis mellifera and the parasitic wasp Nasonia vitripennis. In both cases, wing hair location and wing membrane topography are coordinated on the dorsal, but not ventral, wing surface, suggesting that the dorsal wing epithelium also controls wing topography in these species. Because phylogenomic studies have identified the Hymenotera as basal within the Endopterygota family tree, these findings suggest that this is a primitive insect character.

  4. Death in the intestinal epithelium-basic biology and implications for inflammatory bowel disease.

    PubMed

    Blander, J Magarian

    2016-07-01

    Every 4-5 days, intestinal epithelial cells (IEC) are terminated as they reach the end of their life. This process ensures that the epithelium is comprised of the fittest cells that maintain an impermeable barrier to luminal contents and the gut microbiota, as well as the most metabolically able cells that conduct functions in nutrient absorption, digestion, and secretion of antimicrobial peptides. IEC are terminated by apical extrusion-or shedding-from the intestinal epithelial monolayer into the gut lumen. Whether death by apoptosis signals extrusion or death follows expulsion by younger IEC has been a matter of debate. Seemingly a minor detail, IEC death before or after apical extrusion bears weight on the potential contribution of apoptotic IEC to intestinal homeostasis as a consequence of their recognition by intestinal lamina propria phagocytes. In inflammatory bowel disease (IBD), excessive death is observed in the ileal and colonic epithelium. The precise mode of IEC death in IBD is not defined. A highly inflammatory milieu within the intestinal lamina propria, rich in the proinflammatory cytokine, TNF-α, increases IEC shedding and compromises barrier integrity fueling more inflammation. A milestone in the treatment of IBD, anti-TNF-α therapy, may promote mucosal healing by reversing increased and inflammation-associated IEC death. Understanding the biology and consequences of cell death in the intestinal epithelium is critical to the design of new avenues for IBD therapy.

  5. Assessing DNA methylation in the developing human intestinal epithelium: potential link to inflammatory bowel disease.

    PubMed

    Kraiczy, J; Nayak, K; Ross, A; Raine, T; Mak, T N; Gasparetto, M; Cario, E; Rakyan, V; Heuschkel, R; Zilbauer, M

    2016-05-01

    DNA methylation is one of the major epigenetic mechanisms implicated in regulating cellular development and cell-type-specific gene expression. Here we performed simultaneous genome-wide DNA methylation and gene expression analysis on purified intestinal epithelial cells derived from human fetal gut, healthy pediatric biopsies, and children newly diagnosed with inflammatory bowel disease (IBD). Results were validated using pyrosequencing, real-time PCR, and immunostaining. The functional impact of DNA methylation changes on gene expression was assessed by employing in-vitro assays in intestinal cell lines. DNA methylation analyses allowed identification of 214 genes for which expression is regulated via DNA methylation, i.e. regulatory differentially methylated regions (rDMRs). Pathway and functional analysis of rDMRs suggested a critical role for DNA methylation in regulating gene expression and functional development of the human intestinal epithelium. Moreover, analysis performed on intestinal epithelium of children newly diagnosed with IBD revealed alterations in DNA methylation within genomic loci, which were found to overlap significantly with those undergoing methylation changes during intestinal development. Our study provides novel insights into the physiological role of DNA methylation in regulating functional maturation of the human intestinal epithelium. Moreover, we provide data linking developmentally acquired alterations in the DNA methylation profile to changes seen in pediatric IBD.

  6. GRHL2 coordinates regeneration of a polarized mucociliary epithelium from basal stem cells

    PubMed Central

    Gao, Xia; Bali, Aman S.; Randell, Scott H.

    2015-01-01

    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. PMID:26527742

  7. Heterotopic transplantation of glycerin-preserved trachea: effect of respiratory epithelium desquamation on acute rejection.

    PubMed

    Saueressig, M G; Edelweiss, M I A; Souza, F H; Moreschi, A H; Savegnago, F L; Macedo Neto, A V

    2005-07-01

    An effective preservation method and decreased rejection are essential for tracheal transplantation in the reconstruction of large airway defects. Our objective in the present study was to evaluate the antigenic properties of glycerin-preserved tracheal segments. Sixty-one tracheal segments (2.4 to 3.1 cm) were divided into three groups: autograft (N = 21), fresh allograft (N = 18) and glycerin-preserved allograft (N = 22). Two segments from different groups were implanted into the greater omentum of dogs (N = 31). After 28 days, the segments were harvested and analyzed for mononuclear infiltration score and for the presence of respiratory epithelium. The fresh allograft group presented the highest score for mononuclear infiltration (1.78 +/- 0.43, P < or = 0.001) when compared to the autograft and glycerin-preserved allograft groups. In contrast to the regenerated epithelium observed in autograft segments, all fresh allografts and glycerin-preserved allografts had desquamation of the respiratory mucosa. The low antigenicity observed in glycerin segments was probably the result of denudation of the respiratory epithelium and perhaps due to the decrease of major histocompatibility complex class II antigens. PMID:16007278

  8. Proliferation and differentiation of fetal rat pulmonary epithelium in the absence of mesenchyme.

    PubMed Central

    Deterding, R R; Shannon, J M

    1995-01-01

    Previous studies have shown that pulmonary mesenchyme is required to maintain epithelial viability and to support branching morphogenesis and cytodifferentiation. We have examined whether pulmonary mesenchyme can be replaced by a medium containing a combination of soluble factors. Day 13-14 fetal rat distal lung epithelium was enzymatically separated from its mesenchyme, enrobed in EHS tumor matrix, and cultured for 5 d in medium containing concentrated bronchoalveolar lavage, EGF, acidic fibroblast growth factor, cholera toxin, insulin, and FBS (TGM), or in control medium containing only FBS. After 5 d in culture, marked growth and morphological changes occurred in epithelial rudiments cultured in TGM, whereas no changes were seen in controls. [3H]Thymidine incorporation and nuclear labeling indices during the last 24 h of culture confirmed that epithelial rudiments cultured in TGM had significant proliferative capacities. Evaluation of surfactant protein gene expression by Northern analysis, in situ hybridization, and immunocytochemistry demonstrated that distal lung epithelial differentiation progressed in TGM. Ultrastructural analysis demonstrated that fetal distal lung epithelium cultured in TGM contained lamellar bodies and deposited a basal lamina. These results are the first demonstration that sustained proliferation and differentiation of glandular stage distal pulmonary epithelium can proceed in the absence of mesenchyme. Images PMID:7769139

  9. Airway Epithelium Interactions with Aeroallergens: Role of Secreted Cytokines and Chemokines in Innate Immunity

    PubMed Central

    Gandhi, Vivek D.; Vliagoftis, Harissios

    2015-01-01

    Airway epithelial cells are the first line of defense against the constituents of the inhaled air, which include allergens, pathogens, pollutants, and toxic compounds. The epithelium not only prevents the penetration of these foreign substances into the interstitium, but also senses their presence and informs the organism’s immune system of the impending assault. The epithelium accomplishes the latter through the release of inflammatory cytokines and chemokines that recruit and activate innate immune cells at the site of assault. These epithelial responses aim to eliminate the inhaled foreign substances and minimize their detrimental effects to the organism. Quite frequently, however, the innate immune responses of the epithelium to inhaled substances lead to chronic and high level release of pro-inflammatory mediators that may mediate the lung pathology seen in asthma. The interactions of airway epithelial cells with allergens will be discussed with particular focus on interactions-mediated epithelial release of cytokines and chemokines and their role in the immune response. As pollutants are other major constituents of inhaled air, we will also discuss how pollutants may alter the responses of airway epithelial cells to allergens. PMID:25883597

  10. Testosterone control of nucleic acid content and proliferation of epithelium and stroma in rat seminal vesicles.

    PubMed Central

    Higgins, S J; Burchell, J M; Mainwaring, W I

    1976-01-01

    Tissue wet weight, nucleic acid content and epithelial and stromal cell numbers were measured in the seminal vesicles of sexually mature male rats. After castration, tissue weight and RNA decreased rapidly and in aprallel to reach, after 14 days, values only 15-20% of those in control (not castrated) animals. During this period, DNA decreased to a much lesser extent (by about 40%), but this change in DNA correlates well with the observed loss of cells from the epithelium. Testosterone in vivo promoted an immediate resynthesis of RNA, the value characteristic of control animals being reached within 80h. Delays occurred in the hormone-induced regain of tissue weight (30h) and DNA (40h), each of which preceded proliferation of the epithelium (40--50h). The cells of the stroma were unaffected by these changes in the androgenic statls of the animal. It is suggested that these proliferative changes in the epithelium cannot account for the previously reported induction by testosterone of basic secretory proteins in this tissue. PMID:1008845

  11. Histochemical localization of cholinesterase activity in the dental epithelium of guinea pig teeth.

    PubMed

    Jayawardena, C K; Takano, Y

    2004-07-01

    Cholinesterase is known for its remarkable diversity in distribution and function. An association of this enzyme with proliferative and morpho-differentiating tissues has been reported in several species. Here we report on the first evidence of the presence of cholinesterase in the enamel organ of continuously erupting incisors and molars of the guinea pig. Frozen sections of the incisors and molars of the guinea pig were incubated for histochemical demonstration of cholinesterase activity by means of the thiocholine method as described by Karnovsky and Root. The cholinesterase activity was observed in several types of cells of the dental epithelium; cells forming the basal portion of the enamel organ, outer enamel epithelium and maturation stage ameloblasts of both the incisors and molars. In the crown analogue side, the outer enamel epithelial cells gained strong reactions for cholinesterase and maintained the reaction throughout the secretory and maturation stages of amelogenesis. In contrast, cholinesterase reactions were lacking in the inner enamel epithelium, pre-ameloblasts, and secretory ameloblasts. In the early stage of enamel maturation, ameloblasts began to show positive reactions for cholinesterase, which was upregulated in the incisal direction. Although both tooth types showed similar reactive patterns for cholinesterase at the growing ends, maturation ameloblasts depicted a different pattern of staining displaying the reactions only sporadically in molars. These data indicate the role of cholinesterase in the enamel organ in tooth morphogenesis and function of guinea pig teeth. PMID:15224211

  12. Effects of zinc deficiency on the distribution of membrane-coating granules in rat buccal epithelium.

    PubMed

    Ashrafi, S H; Meyer, J; Squier, C A

    1980-06-01

    Nutritional zinc deficiency causes consistent excessive cell proliferation in the epithelium of the buccal mucosa. The number per cell and the intracellular location of membrane-coating granules in this epithelium were investigated in male rats placed at weanling age for a 4-week period on a diet containing 1.2 ppm of Zn and in their pair fed controls. Membrane-coating granules were identified on electron micrographs following their demonstration in thin sections by the use of an alkaline bismuth technique. Counts of membrane-coating granules in the first 4 rows of spinous cells and the last 4 rows of granular cells showed that in the zinc-deficient group (1) the total number of granules per cell was increased; (2) the proportion of granules displaced to the cell periphery was decreased in favor of a higher proportion persisting in the center and (3) there was a marked reduction in number and proportion of granules positioned near the superficial cell membrane. The greater uniformity in the distribution of the granules in the hyperplastic-hypertrophic epithelium of the zinc deficient group suggests weakening of the surface-oriented polarity characteristic of the control tissue.

  13. Midgut epithelium in molting silkworm: A fine balance among cell growth, differentiation, and survival.

    PubMed

    Franzetti, Eleonora; Casartelli, Morena; D'Antona, Paola; Montali, Aurora; Romanelli, Davide; Cappellozza, Silvia; Caccia, Silvia; Grimaldi, Annalisa; de Eguileor, Magda; Tettamanti, Gianluca

    2016-07-01

    The midgut of insects has attracted great attention as a system for studying intestinal stem cells (ISCs) as well as cell death-related processes, such as apoptosis and autophagy. Among insects, Lepidoptera represent a good model to analyze these cells and processes. In particular, larva-larva molting is an interesting developmental phase since the larva must deal with nutrient starvation and its organs are subjected to rearrangements due to proliferation and differentiation events. Several studies have analyzed ISCs in vitro and characterized key factors involved in their division and differentiation during molt. However, in vivo studies performed during larva-larva transition on these cells, and on the whole midgut epithelium, are fragmentary. In the present study, we analyzed the larval midgut epithelium of the silkworm, Bombyx mori, during larva-larva molting, focusing our attention on ISCs. Moreover, we investigated the metabolic changes that occur in the epithelium and evaluated the intervention of autophagy. Our data on ISCs proliferation and differentiation, autophagy activation, and metabolic and functional activities of the midgut cells shed light on the complexity of this organ during the molting phase. PMID:27349418

  14. Weather Modification: Finding Common Ground.

    NASA Astrophysics Data System (ADS)

    Garstang, Michael; Bruintjes, Roelof; Serafin, Robert; Orville, Harold; Boe, Bruce; Cotton, William; Warburton, Joseph

    2005-05-01

    Research and operational approaches to weather modification expressed in the National Research Council's 2003 report on “Critical Issues in Weather Modification Research” and in the Weather Modification Association's response to that report form the basis for this discussion. There is agreement that advances in the past few decades over a broad front of understanding physical processes and in technology have not been comprehensively applied to weather modification. Such advances need to be capitalized upon in the form of a concerted and sustained national effort to carry out basic and applied research in weather modification. The need for credible scientific evidence and the pressure for action should be resolved. Differences in the perception of current knowledge, the utility of numerical models, and the specific needs of research and operations in weather modification must be addressed. The increasing demand for water and the cost to society inflicted by severe weather require that the intellectual, technical, and administrative resources of the nation be combined to resolve whether and to what degree humans can influence the weather.The National Center for Atmospheric Research is sponsored by the National Science Foundation


  15. Optimizing modulation frequency for structured illumination in a fiber-optic microendoscope to image nuclear morphometry in columnar epithelium.

    PubMed

    Keahey, P A; Tkaczyk, T S; Schmeler, K M; Richards-Kortum, R R

    2015-03-01

    Fiber-optic microendoscopes have shown promise to image the changes in nuclear morphometry that accompany the development of precancerous lesions in tissue with squamous epithelium such as in the oral mucosa and cervix. However, fiber-optic microendoscopy image contrast is limited by out-of-focus light generated by scattering within tissue. The scattering coefficient of tissues with columnar epithelium can be greater than that of squamous epithelium resulting in decreased image quality. To address this challenge, we present a small and portable microendoscope system capable of performing optical sectioning using structured illumination (SI) in real-time. Several optical phantoms were developed and used to quantify the sectioning capabilities of the system. Columnar epithelium from cervical tissue specimens was then imaged ex vivo, and we demonstrate that the addition of SI achieves higher image contrast, enabling visualization of nuclear morphology.

  16. Phenotypic and physiologic variability in nasal epithelium cultured from smokers and non-smokers exposed to secondhand tobacco smoke

    EPA Science Inventory

    The emergence of air-liquid interface (ALI) culturing of mammalian airway epithelium is a recent innovation for experimental modeling of airway epithelial development, function, and pathogenic mechanisms associated with infectious agent and irritant exposure. This construct provi...

  17. Small Interfering RNA Pathway Modulates Initial Viral Infection in Midgut Epithelium of Insect after Ingestion of Virus

    PubMed Central

    Lan, Hanhong; Chen, Hongyan; Liu, Yuyan; Jiang, Chaoyang; Mao, Qianzhuo; Jia, Dongsheng; Chen, Qian

    2015-01-01

    ABSTRACT Numerous viruses are transmitted in a persistent manner by insect vectors. Persistent viruses establish their initial infection in the midgut epithelium, from where they disseminate to the midgut visceral muscles. Although propagation of viruses in insect vectors can be controlled by the small interfering RNA (siRNA) antiviral pathway, whether the siRNA pathway can control viral dissemination from the midgut epithelium is unknown. Infection by a rice virus (Southern rice black streaked dwarf virus [SRBSDV]) of its incompetent vector (the small brown planthopper [SBPH]) is restricted to the midgut epithelium. Here, we show that the siRNA pathway is triggered by SRBSDV infection in continuously cultured cells derived from the SBPH and in the midgut of the intact insect. Knockdown of the expression of the core component Dicer-2 of the siRNA pathway by RNA interference strongly increased the ability of SRBSDV to propagate in continuously cultured SBPH cells and in the midgut epithelium, allowing viral titers in the midgut epithelium to reach the threshold (1.99 × 109 copies of the SRBSDV P10 gene/μg of midgut RNA) needed for viral dissemination into the SBPH midgut muscles. Our results thus represent the first elucidation of the threshold for viral dissemination from the insect midgut epithelium. Silencing of Dicer-2 further facilitated the transmission of SRBSDV into rice plants by SBPHs. Taken together, our results reveal the new finding that the siRNA pathway can control the initial infection of the insect midgut epithelium by a virus, which finally affects the competence of the virus's vector. IMPORTANCE Many viral pathogens that cause significant global health and agricultural problems are transmitted via insect vectors. The first bottleneck in viral infection, the midgut epithelium, is a principal determinant of the ability of an insect species to transmit a virus. Southern rice black streaked dwarf virus (SRBSDV) is restricted exclusively to the

  18. Nrf2 deficiency impairs the barrier function of mouse esophageal epithelium

    PubMed Central

    Chen, Hao; Hu, Yuhui; Fang, Yu; Djukic, Zorka; Yamamoto, Masayuki; Shaheen, Nicholas J.; Orlando, Roy C.; Chen, Xiaoxin

    2013-01-01

    Objective As a major cellular defense mechanism, the Nrf2/Keap1 pathway regulates expression of genes involved in detoxification and stress response. Our previous study revealed activation of the Nrf2/Keap1 pathway at the maturation phase during mouse esophageal development, suggesting a potential function in epithelial defense. Here we hypothesize that Nrf2 is involved in the barrier function of esophageal epithelium, and plays a protective role against gastroesophageal reflux disease (GERD). Design Human esophageal biopsy samples, mouse surgical models and Nrf2-/- mice were used to assess the role of the Nrf2/Keap1 pathway in esophageal mucosal barrier function. Trans-epithelial electrical resistance (TEER) was measured with mini-Ussing chambers. Hematoxylin and eosin (HE) staining and transmission electron microscopy were used to examine cell morphology, while gene microarray, immunohistochemistry, Western blotting and ChIP analysis were used to assess the expression of pathway genes. Results Nrf2 was expressed in normal esophageal epithelium and activated in GERD of both humans and mice. Nrf2 deficiency and gastroesophageal reflux in mice, either alone or in combination, reduced TEER and increased intercellular space diameter in esophageal epithelium. Nrf2 target genes and gene sets associated with oxidoreductase activity, mitochondrial biogenesis and energy production were down-regulated in the esophageal epithelium of Nrf2-/- mice. Consistent with the antioxidative function of Nrf2, a DNA oxidative damage marker (8OHdG) dramatically increased in esophageal epithelial cells of Nrf2-/- mice compared with those of wild-type mice. Interestingly, ATP biogenesis, Cox IV (a mitochondrial protein) and Claudin-4 (Cldn4) expression were down-regulated in the esophageal epithelium of Nrf2-/- mice, suggesting that energy-dependent tight junction integrity was subject to Nrf2 regulation. ChIP analysis confirmed the binding of Nrf2 to Cldn4 promoter. Conclusion Nrf2

  19. Induction of Subacute Ruminal Acidosis Affects the Ruminal Microbiome and Epithelium.

    PubMed

    McCann, Joshua C; Luan, Shaoyu; Cardoso, Felipe C; Derakhshani, Hooman; Khafipour, Ehsan; Loor, Juan J

    2016-01-01

    Subacute ruminal acidosis (SARA) negatively impacts the dairy industry by decreasing dry matter intake, milk production, profitability, and increasing culling rate and death loss. Six ruminally cannulated, lactating Holstein cows were used in a replicated incomplete Latin square design to determine the effects of SARA induction on the ruminal microbiome and epithelium. Experimental periods were 10 days with days 1-3 for ad libitum intake of control diet, followed by 50% feed restriction on day 4, and ad libitum access on day 5 to the basal diet or the basal diet with an additional 10% of a 50:50 wheat/barley pellet. Based on subsequent ruminal pH, cows were grouped (SARA grouping; SG) as Non-SARA or SARA based on time <5.6 pH (0 and 3.4 h, respectively). Ruminal samples were collected on days 1 and 6 of each period prior to feeding and separated into liquid and solid fractions. Microbial DNA was extracted for bacterial analysis using 16S rRNA gene paired-end sequencing on the MiSeq Illumina platform and quantitative PCR (qPCR). Ruminal epithelium biopsies were taken on days 1 and 6 before feeding. Quantitative RT-PCR was used to determine gene expression in rumen epithelium. Bray-Curtis similarity indicated samples within the liquid fraction separated by day and coincided with an increased relative abundance of genera Prevotella, Ruminococcus, Streptococcus, and Lactobacillus on day 6 (P < 0.06). Although Firmicutes was the predominant phyla in the solid fraction, a SG × day interaction (P < 0.01) indicated a decrease on day 6 for SARA cows. In contrast, phylum Bacteroidetes increased on day 6 (P < 0.01) for SARA cows driven by greater genera Prevotella and YRC22 (P < 0.01). Streptococcus bovis and Succinivibrio dextrinosolvens populations tended to increase on day 6 but were not affected by SG. In ruminal epithelium, CLDN1 and CLDN4 expression increased on day 6 (P < 0.03) 24 h after SARA induction and a tendency for a SG × day interaction (P < 0.10) was

  20. Epithelium-on corneal cross-linking treatment of progressive keratoconus: a prospective, consecutive study

    PubMed Central

    Khairy, Hany A; Marey, Hatem M; Ellakwa, Amin Faisal

    2014-01-01

    Purpose To evaluate the outcome of collagen cross-linking (CXL) without corneal epithelial debridement in patients treated for progressive keratoconus for whom the standard epithelium-off treatment cannot be applied, as their central corneal thickness (CCT) is less than 400 μm. Patients and methods This was a prospective, uncontrolled, interventional study involving 32 eyes of 30 patients with progressive keratoconus and CCT of less than 400 μm. All patients received CXL treatment with application of riboflavin and exposure to ultraviolet light A for 30 minutes without corneal epithelial debridement. Patients were followed up to 12 months postoperatively. The main outcomes were changes in maximum-K reading, manifest refractive spherical equivalent, CCT, and best-corrected visual acuity (logarithm of minimum angle of resolution). Patients were also asked to report any pain or discomfort during the procedure. Results At the end of the 12-month follow-up, CCT showed no significant change: from 392±5.17 μm preoperatively to 390±4.45 μm (P=0.102). Maximum-K reading decreased significantly, from 49.19±2.30 D preoperatively to 46.96±6.03 D postoperatively (P<0.05). The mean manifest spherical equivalent showed no significant change: from 4.04±1.51 D preoperatively to 4.17±1.63 D postoperatively (P=0.110). Mean best-corrected visual acuity showed no significant change: from 0.29±0.12 preoperatively to 0.31±0.11 postoperatively (P=0.110). Conclusion Epithelium-on CXL exhibits potential as a method for treating patients with progressive keratoconus and CCT of less than 400 μm, in which the standard epithelium-off CXL cannot be applied. Over 12 months of follow-up, the epithelium-on CXL was safe and effective, with results comparable to that achieved with the epithelium-off technique in thicker corneas, and reduced rates of operative and postoperative discomfort. PMID:24812488

  1. Induction of Subacute Ruminal Acidosis Affects the Ruminal Microbiome and Epithelium

    PubMed Central

    McCann, Joshua C.; Luan, Shaoyu; Cardoso, Felipe C.; Derakhshani, Hooman; Khafipour, Ehsan; Loor, Juan J.

    2016-01-01

    Subacute ruminal acidosis (SARA) negatively impacts the dairy industry by decreasing dry matter intake, milk production, profitability, and increasing culling rate and death loss. Six ruminally cannulated, lactating Holstein cows were used in a replicated incomplete Latin square design to determine the effects of SARA induction on the ruminal microbiome and epithelium. Experimental periods were 10 days with days 1–3 for ad libitum intake of control diet, followed by 50% feed restriction on day 4, and ad libitum access on day 5 to the basal diet or the basal diet with an additional 10% of a 50:50 wheat/barley pellet. Based on subsequent ruminal pH, cows were grouped (SARA grouping; SG) as Non-SARA or SARA based on time <5.6 pH (0 and 3.4 h, respectively). Ruminal samples were collected on days 1 and 6 of each period prior to feeding and separated into liquid and solid fractions. Microbial DNA was extracted for bacterial analysis using 16S rRNA gene paired-end sequencing on the MiSeq Illumina platform and quantitative PCR (qPCR). Ruminal epithelium biopsies were taken on days 1 and 6 before feeding. Quantitative RT-PCR was used to determine gene expression in rumen epithelium. Bray–Curtis similarity indicated samples within the liquid fraction separated by day and coincided with an increased relative abundance of genera Prevotella, Ruminococcus, Streptococcus, and Lactobacillus on day 6 (P < 0.06). Although Firmicutes was the predominant phyla in the solid fraction, a SG × day interaction (P < 0.01) indicated a decrease on day 6 for SARA cows. In contrast, phylum Bacteroidetes increased on day 6 (P < 0.01) for SARA cows driven by greater genera Prevotella and YRC22 (P < 0.01). Streptococcus bovis and Succinivibrio dextrinosolvens populations tended to increase on day 6 but were not affected by SG. In ruminal epithelium, CLDN1 and CLDN4 expression increased on day 6 (P < 0.03) 24 h after SARA induction and a tendency for a SG × day interaction (P < 0.10) was

  2. Ultrastructure and chloride cytochemistry of the hindgut epithelium in the larvae of the seawater mosquito, Aëdes togoi Theobald.

    PubMed

    Asakura, K

    1982-05-01

    The hindgut of Aëdes togoi larvae adapted to various external salinities was studied by light and electron microscopy. The larvae's pyloric chamber and the ileum of the hindgut are surrounded by a thick muscular layer and lined with a very thin unspecialized epithelium. There is no detectable difference in the ultrastructural organization of the epithelium between seawater-adapted and freshwater-adapted larvae. The rectum and the anal canal are greatly dilated and densely tracheated and have a very thick, highly specialized epithelium. The rectal epithelium is characterized by shorter apical and longer basal infoldings closely associated with mitochondria, and a particulate coating on the apical infoldings. The intercellular spaces and the basal channels are tightly closed in the rectal epithelium of freshwater-adapted larvae, whereas widely dilated in that of 100 to 200% seawater-adapted larvae. The rectum seems to reabsorb water from excretory fluid when larvae are in hyperosmotic media. The anal canal epithelium possesses well-developed apical infoldings, which are coated with small particles an intimately associated with mitochondria. The basal infoldings are short. No perceptible difference in the ultrastructural organization of the epithelium was observed between seawater-adapted and freshwater-adapted larvae. The lumina of the apical infoldings of the anal canal epithelium in seawater-adapted larvae, however, demonstrated a strongly positive reaction to the cytochemical assay for chloride ions, whereas the reaction was very weak in freshwater-adapted larvae. Unlike salt-water-mosquito larvae of the other species, in which the rectum is considered to be concerned with the formation of hyperosmotic urine, the anal canal in A. togoi larvae seems to play an important role in excretion of excess ions in the haemolymph when adapted to hyperosmotic media.

  3. Transcriptional responses in the rat nasal epithelium following subchronic inhalation of naphthalene vapor

    SciTech Connect

    Clewell, H.J. Efremenko, A.; Campbell, J.L.; Dodd, D.E.; Thomas, R.S.

    2014-10-01

    Male and female Fischer 344 rats were exposed to naphthalene vapors at 0 (controls), 0.1, 1, 10, and 30 ppm for 6 h/d, 5 d/wk, over a 90-day period. Following exposure, the respiratory epithelium and olfactory epithelium from the nasal cavity were dissected separately, RNA was isolated, and gene expression microarray analysis was conducted. Only a few significant gene expression changes were observed in the olfactory or respiratory epithelium of either gender at the lowest concentration (0.1 ppm). At the 1.0 ppm concentration there was limited evidence of an oxidative stress response in the respiratory epithelium, but not in the olfactory epithelium. In contrast, a large number of significantly enriched cellular pathway responses were observed in both tissues at the two highest concentrations (10 and 30 ppm, which correspond to tumorigenic concentrations in the NTP bioassay). The nature of these responses supports a mode of action involving oxidative stress, inflammation and proliferation. These results are consistent with a dose-dependent transition in the mode of action for naphthalene toxicity/carcinogenicity between 1.0 and 10 ppm in the rat. In the female olfactory epithelium (the gender/site with the highest incidences of neuroblastomas in the NTP bioassay), the lowest concentration at which any signaling pathway was significantly affected, as characterized by the median pathway benchmark dose (BMD) or its 95% lower bound (BMDL) was 6.0 or 3.7 ppm, respectively, while the lowest female olfactory BMD values for pathways related to glutathione homeostasis, inflammation, and proliferation were 16.1, 11.1, and 8.4 ppm, respectively. In the male respiratory epithelium (the gender/site with the highest incidences of adenomas in the NTP bioassay), the lowest pathway BMD and BMDL were 0.4 and 0.3 ppm, respectively, and the lowest male respiratory BMD values for pathways related to glutathione homeostasis, inflammation, and proliferation were 0.5, 0.7, and 0.9 ppm

  4. Lesion of the Olfactory Epithelium Accelerates Prion Neuroinvasion and Disease Onset when Prion Replication Is Restricted to Neurons

    PubMed Central

    Crowell, Jenna; Wiley, James A.; Bessen, Richard A.

    2015-01-01

    Natural prion diseases of ruminants are moderately contagious and while the gastrointestinal tract is the primary site of prion agent entry, other mucosae may be entry sites in a subset of infections. In the current study we examined prion neuroinvasion and disease induction following disruption of the olfactory epithelium in the nasal mucosa since this site contains environmentally exposed olfactory sensory neurons that project directly into the central nervous system. Here we provide evidence for accelerated prion neuroinvasion and clinical onset from the olfactory mucosa after disruption and regeneration of the olfactory epithelium and when prion replication is restricted to neurons. In transgenic mice with neuron restricted replication of prions, there was a reduction in survival when the olfactory epithelium was disrupted prior to intranasal inoculation and there was >25% decrease in the prion incubation period. In a second model, the neurotropic DY strain of transmissible mink encephalopathy was not pathogenic in hamsters by the nasal route, but 50% of animals exhibited brain infection and/or disease when the olfactory epithelium was disrupted prior to intranasal inoculation. A time course analysis of prion deposition in the brain following loss of the olfactory epithelium in models of neuron-restricted prion replication suggests that neuroinvasion from the olfactory mucosa is via the olfactory nerve or brain stem associated cranial nerves. We propose that induction of neurogenesis after damage to the olfactory epithelium can lead to prion infection of immature olfactory sensory neurons and accelerate prion spread to the brain. PMID:25822718

  5. Magnifying endoscopy with narrow-band imaging findings in the diagnosis of Barrett's esophageal adenocarcinoma spreading below squamous epithelium.

    PubMed

    Omae, Masami; Fujisaki, Junko; Shimizu, Tomoki; Igarashi, Masahiro; Yamamoto, Noriko

    2013-05-01

    It has been described that most cases of Barrett's esophageal adenocarcinoma in Japan are cases of Barrett's esophageal adenocarcinoma on a background of short-segment Barrett's esophagus, frequently occurring rostrad to Barrett's epithelium, adjacent to the squamous epithelium of the right wall of the esophagogastric junction. Barrett's esophageal adenocarcinoma may spread below the squamous epithelium when the tumor is situated adjacent to the squamocolumnar junction, so that it is usually difficult to diagnose its presence and extent by conventional endoscopy alone. We have noted that the spread of Barrett's esophageal adenocarcinoma below the squamous epithelium is recognizable as annular vascular formations (AVF) by magnifying endoscopy with narrow-band imaging (ME-NBI), and have verified it by 3-D stereo-reconstruction using serial sections from a specimen of the same lesion. When horizontal cross-sections of the tissue were viewed from the surface, AVF emerged at a depth of approximately 100 μm from the surface and disappeared at a depth of approximately 300 μm. Therefore, it would be presumed to be difficult to visualize the characteristic structural features by ME-NBI if the carcinomatous glandular ducts were situated deeper than approximately 300 μm underneath a thick layer of squamous epithelium. Thickness of the overlying squamous epithelium may be a limiting factor for whether or not the characteristic structural features can be detected.

  6. Surface modification for corrosion resistance

    SciTech Connect

    Natesan, K.

    1993-06-01

    The raw gas environments that arise from coal gasification have chemical compositions that are low in pO{sub 2} and moderate-to-high in pS{sub 2}. Metallic materials for service in such an environment undergo predominantly sulfidation attack at temperatures of 400 to 700{degree}C. Modification of alloy compositions in bulk can alter the scaling processes and lead to improvements in corrosion resistance, but the benefits can only be attained at temperatures much higher than the service temperatures of the components. Modification of surfaces of structural components by several of the coating techniques examined in this study showed substantial benefit in corrosion resistance when tested in simulated coal gasification environments. The paper presents several examples of surface modification and their corrosion performance.

  7. Laser modification of polyamide fabrics

    NASA Astrophysics Data System (ADS)

    Bahtiyari, M. İ.

    2011-02-01

    A new method for the modification of the properties of polyamide fabric, based on exposure to the output from a CO 2 laser, has been investigated. It was found that, after laser modification of polyamide fabric, the dyeability of fabric was increased significantly, while the bursting strength was decreased. The reasons for this drastic increase in dyeability of polyamide fabrics have been analyzed with the help of FTIR and iodine sorption methods, revealing a relationship with a decrease in the crystallinity of the polyamide. It was observed that, as the laser modification of the fabric was carried out with low intensity, the concentration of free amino groups, which are necessary during dyeing with acid and reactive dyes, increased.

  8. Playing TETris with DNA modifications

    PubMed Central

    Delatte, Benjamin; Deplus, Rachel; Fuks, François

    2014-01-01

    Methylation of the fifth carbon of cytosine was the first epigenetic modification to be discovered in DNA. Recently, three new DNA modifications have come to light: hydroxymethylcytosine, formylcytosine, and carboxylcytosine, all generated by oxidation of methylcytosine by Ten Eleven Translocation (TET) enzymes. These modifications can initiate full DNA demethylation, but they are also likely to participate, like methylcytosine, in epigenetic signalling per se. A scenario is emerging in which coordinated regulation at multiple levels governs the participation of TETs in a wide range of physiological functions, sometimes via a mechanism unrelated to their enzymatic activity. Although still under construction, a sophisticated picture is rapidly forming where, according to the function to be performed, TETs ensure epigenetic marking to create specific landscapes, and whose improper build-up can lead to diseases such as cancer and neurodegenerative disorders. PMID:24825349

  9. Manufacturer evaluations of endograft modifications.

    PubMed

    Waninger, Matthew S; Whirley, Robert G; Smith, Louis J; Wolf, Ben S

    2013-03-01

    The motivation to modify the design of a vascular device can arise from a number of sources. Clinical experience with the unmodified device could suggest new design modifications to improve device performance or clinical outcomes. Similarly, clinical success with a device often suggests modifications that could broaden the applicability of the device to enable treatment of different or more advanced disease states. As a specific example, both of these scenarios have arisen during the last decade in the evolution of endovascular grafts for the treatment of abdominal aortic aneurysms, with modifications enabling the treatment of patients with shorter infrarenal necks, more angulated anatomy, and smaller access vessels. These modifications have been made by manufacturers and additionally by physicians who create branched and fenestrated devices. The experience to date with the use of fenestrated devices and the development of chimney, snorkel, and periscope techniques suggests that modifications to off-the-shelf devices may provide some clinical benefit. This experience provides additional motivation for manufacturers to develop devices to address the clinical needs not met with their current product lines. For manufacturers, the device development process includes an assessment of the new device design to determine the appropriate evaluation strategy to support the safety and effectiveness of the modified device. This report provides a high-level overview of the process generally followed by device manufacturers to evaluate a proposed device modification before market release, in accordance with local country regulations and recognized international standards such as the International Organization of Standardization (ISO) standards for endovascular grafts (ISO 25539 Part 1).

  10. Manufacturer evaluations of endograft modifications.

    PubMed

    Waninger, Matthew S; Whirley, Robert G; Smith, Louis J; Wolf, Ben S

    2013-03-01

    The motivation to modify the design of a vascular device can arise from a number of sources. Clinical experience with the unmodified device could suggest new design modifications to improve device performance or clinical outcomes. Similarly, clinical success with a device often suggests modifications that could broaden the applicability of the device to enable treatment of different or more advanced disease states. As a specific example, both of these scenarios have arisen during the last decade in the evolution of endovascular grafts for the treatment of abdominal aortic aneurysms, with modifications enabling the treatment of patients with shorter infrarenal necks, more angulated anatomy, and smaller access vessels. These modifications have been made by manufacturers and additionally by physicians who create branched and fenestrated devices. The experience to date with the use of fenestrated devices and the development of chimney, snorkel, and periscope techniques suggests that modifications to off-the-shelf devices may provide some clinical benefit. This experience provides additional motivation for manufacturers to develop devices to address the clinical needs not met with their current product lines. For manufacturers, the device development process includes an assessment of the new device design to determine the appropriate evaluation strategy to support the safety and effectiveness of the modified device. This report provides a high-level overview of the process generally followed by device manufacturers to evaluate a proposed device modification before market release, in accordance with local country regulations and recognized international standards such as the International Organization of Standardization (ISO) standards for endovascular grafts (ISO 25539 Part 1). PMID:23446123

  11. Transport of butyrate across the isolated bovine rumen epithelium--interaction with sodium, chloride and bicarbonate.

    PubMed

    Sehested, J; Diernaes, L; Møller, P D; Skadhauge, E

    1999-08-01

    The Ussing chamber technique was used for studying unidirectional fluxes of 14C-butyrate across the bovine rumen epithelium in vitro. Significant amounts of butyrate were absorbed across the bovine rumen epithelium in vitro, without any external driving force. The paracellular pathway was quantitatively insignificant. The transcellular pathway was predominately voltage-insensitive. The serosal to mucosal (SM) pathway was regulated by mass action, whereas the mucosal to serosal (MS) pathway further includes a saturable process, which accounted for 30 to 55% of the MS flux. The studied transport process for 14C-butyrate across the epithelium could include metabolic processes and transport of 14C-labelled butyrate metabolites. The transport of butyrate interacted with Na+, Cl- and HCO3-, and there was a linear relationship between butyrate and sodium net transport. Lowering the sodium concentration from 140 to 10 mmol l-1 decreased the butyrate MS flux significantly. Amiloride (1 mmol l-1) did, however, not reduce the butyrate flux significantly. Chloride concentration in itself did not seem to influence the transport of butyrate, but chloride-free conditions tended to increase the MS and SM flux of butyrate by a DIDS-sensitive pathway. DIDS (bilateral 0.5 mmol l-1) did further decrease the butyrate SM flux significantly at all chloride concentrations. Removing bicarbonate from the experimental solutions decreased the MS and increased the SM flux of butyrate significantly, and abolished net butyrate flux. There were no significant effects of the carbonic anhydrase inhibitor Acetazolamide (bilateral 1.0 mmol l-1). The results can be explained by a model where butyrate and butyrate metabolites are transported both by passive diffusion and by an electroneutral anion-exchange with bicarbonate. The model couples sodium and butyrate via CO2 from metabolism of butyrate, and intracellular pH.

  12. Transport of Na and Cl across the epithelium of ruminant forestomachs: rumen and omasum. A review.

    PubMed

    Martens, H; Gäbel, G

    1988-01-01

    Rumen: 1. It is generally accepted that sodium and chloride is transported across the rumen epithelium of ruminants in the mucosal-serosal direction by an active transport mechanism. In all in vitro studies the short circuit current, Isc, was significantly lower than the net transport of sodium, JNanet. It was concluded that most of the sodium is transported by an electrically silent mechanism. A Na, Cl cotransport and/or a double exchange system Na/H and Cl/HCO3 was proposed. 2. Recent in vitro studies in our laboratory revealed that the Na/H exchange inhibitor amiloride (1 mmol/l) reduced JNanet by 70%. The Na/K/2Cl-cotransport inhibitor bumetanide or furosemide (1 mmol/l) had no effect. 3. Replacement of permeable anions led to an inhibition of JNanet by 87%. However, under these experimental conditions Isc and JNanet were not significantly different. The remaining small electrogen transport of sodium was not influenced by mucosal amiloride. 4. It is concluded that two transport systems are operating in the ruminal epithelium: a Na/H exchange system which accounts for 80-90% of JNanet and an electrogen Na transport which is not sensitive against amiloride. Omasum: 1. The data concerning the transport of sodium and chloride in the omasum are very limited. In vivo measurements of flow rates demonstrated that sodium is absorbed by the omasum (40-60% of inflow in bull calves, 10-20% in sheep) and chloride is secreted. 2. In vitro studies with isolated preparation of sheep omasum epithelium demonstrated a net transport of Na and Cl in the mucosal-serosal direction. JNanet is completely abolished by ouabain (0.1 mmol/1) and JClnet by replacement of Na.

  13. Global expression profiling of globose basal cells and neurogenic progression within the olfactory epithelium.

    PubMed

    Krolewski, Richard C; Packard, Adam; Schwob, James E

    2013-03-01

    Ongoing, lifelong neurogenesis maintains the neuronal population of the olfactory epithelium in the face of piecemeal neuronal turnover and restores it following wholesale loss. The molecular phenotypes corresponding to different stages along the progression from multipotent globose basal cell (GBC) progenitor to differentiated olfactory sensory neuron are poorly characterized. We used the transgenic expression of enhanced green fluorescent protein (eGFP) and cell surface markers to FACS-isolate ΔSox2-eGFP(+) GBCs, Neurog1-eGFP(+) GBCs and immature neurons, and ΔOMP-eGFP(+) mature neurons from normal adult mice. In addition, the latter two populations were also collected 3 weeks after olfactory bulb ablation, a lesion that results in persistently elevated neurogenesis. Global profiling of mRNA from the populations indicates that all stages of neurogenesis share a cohort of >2,100 genes that are upregulated compared to sustentacular cells. A further cohort of >1,200 genes are specifically upregulated in GBCs as compared to sustentacular cells and differentiated neurons. The increased rate of neurogenesis caused by olfactory bulbectomy had little effect on the transcriptional profile of the Neurog1-eGFP(+) population. In contrast, the abbreviated lifespan of ΔOMP-eGFP(+) neurons born in the absence of the bulb correlated with substantial differences in gene expression as compared to the mature neurons of the normal epithelium. Detailed examination of the specific genes upregulated in the different progenitor populations revealed that the chromatin modifying complex proteins LSD1 and coREST were expressed sequentially in upstream ΔSox2-eGFP(+) GBCs and Neurog1-eGFP(+) GBCs/immature neurons. The expression patterns of these proteins are dynamically regulated after activation of the epithelium by methyl bromide lesion.

  14. Near Equilibrium Calculus of Stem Cells in Application to the Airway Epithelium Lineage

    PubMed Central

    Sun, Zheng; Plikus, Maksim V.; Komarova, Natalia L.

    2016-01-01

    Homeostatic maintenance of tissues is orchestrated by well tuned networks of cellular signaling. Such networks regulate, in a stochastic manner, fates of all cells within the respective lineages. Processes such as symmetric and asymmetric divisions, differentiation, de-differentiation, and death have to be controlled in a dynamic fashion, such that the cell population is maintained at a stable equilibrium, has a sufficiently low level of stochastic variation, and is capable of responding efficiently to external damage. Cellular lineages in real tissues may consist of a number of different cell types, connected by hierarchical relationships, albeit not necessarily linear, and engaged in a number of different processes. Here we develop a general mathematical methodology for near equilibrium studies of arbitrarily complex hierarchical cell populations, under regulation by a control network. This methodology allows us to (1) determine stability properties of the network, (2) calculate the stochastic variance, and (3) predict how different control mechanisms affect stability and robustness of the system. We demonstrate the versatility of this tool by using the example of the airway epithelium lineage. Recent research shows that airway epithelium stem cells divide mostly asymmetrically, while the so-called secretory cells divide predominantly symmetrically. It further provides quantitative data on the recovery dynamics of the airway epithelium, which can include secretory cell de-differentiation. Using our new methodology, we demonstrate that while a number of regulatory networks can be compatible with the observed recovery behavior, the observed division patterns of cells are the most optimal from the viewpoint of homeostatic lineage stability and minimizing the variation of the cell population size. This not only explains the observed yet poorly understood features of airway tissue architecture, but also helps to deduce the information on the still largely hypothetical

  15. [Electron microscopic study of the intestinal epithelium of Saccoglossus mereschkowskii (Enteropneusta, Hemichordata)].

    PubMed

    Stoliarova, M V

    2011-01-01

    Epithelium of the hepatic region of the intestine in Saccoglossus mereschkowskii, a representative of enteropneusts (Enteropneusta, Hemichordata) standing at the base of Chordata, has been investigated using electron microscope. The ultrastructure of ciliated and granular epithelial cells, elements of the intraepithelial nerve layer, and intercellular junctions have been characterized. The data concerning details of the organization of the ciliary apparatus and rootlets system are presented. It is justified the presence of complicated supporting construction of cilia which performs a mechanical stabilizing function and possibly also provide synchronization of ciliary movements. The presence of cilia with two centrioles is considered as an adaptation to high functional load on ciliary apparatus. Well developed bundles of myofilaments are found in the cytoplasm of the basal portions of ciliary cells that characterizes these cells as myoepithelial. The features indicating the role of ciliary cells in absorption are described. The capability of these cells to balloon-like secretion is considered. Data on the accumulation of food reserves in the form of lipid droplets and glycogen in the cell cytoplasm are presented. Ciliated cells are characterized by their function as ciliated secretory-absorptive myoepithelial cells. Based on the location of secretory granules both in the apical and basal portions of granular cells, an exocrine-endocrine function of these cells has been suggested. Typical endocrine cells in the intestinal epithelium of S. mereschkowskii are absent. Several types of granules in the nerve fibers cytoplasm are described. Junctions between the nerve fibers and basal portions of ciliary and granular epithelial cells are found. Nerve regulation of contractile and secretory functions of epithelial cells is supposed. The presence of the regulatory nerve-endocrine system that includes receptor cells of open type, secretory endocrine-like cells and nerve

  16. Ontogeny and innervation of taste buds in mouse palatal gustatory epithelium.

    PubMed

    Rashwan, Ahmed; Konishi, Hiroyuki; El-Sharaby, Ashraf; Kiyama, Hiroshi

    2016-01-01

    We investigated the relationship between mouse taste bud development and innervation of the soft palate. We employed scanning electron microscopy and immunohistochemistry using antibodies against protein gene product 9.5 and peripherin to detect sensory nerves, and cytokeratin 8 and α-gustducin to stain palatal taste buds. At E14, nerve fibers were observed along the medial border of the palatal shelves that tracked toward the epithelium. At E15.5, primordial stages of taste buds in the basal lamina of the soft palate first appeared. At E16, the taste buds became large spherical masses of columnar cells scattered in the soft palate basal lamina. At E17, the morphology and also the location of taste buds changed. At E18-19, some taste buds acquired a more elongated shape with a short neck, extending a variable distance from the soft palate basal lamina toward the surface epithelium. At E18, mature taste buds with taste pores and perigemmal nerve fibers were observed on the surface epithelium of the soft palate. The expression of α-gustducin was demonstrated at postnatal day 1 and the number of pored taste buds increased with age and they became pear-shaped at 8 weeks. The percent of pored fungiform-like papillae at birth was 58.3% of the whole palate; this increased to 83.8% at postnatal day 8 and reached a maximum of 95.7% at 12 weeks. The innervation of the soft palate was classified into three types of plexuses in relation to taste buds: basal nerve plexus, intragemmal and perigemmal nerve fibers. This study reveals that the nerve fibers preceded the development of taste buds in the palate of mice, and therefore the nerve fibers have roles in the initial induction of taste buds in the soft palate.

  17. Epithelial-connective tissue cross-talk is essential for regeneration of intestinal epithelium.

    PubMed

    Ishizuya-Oka, Atsuko

    2005-02-01

    Epithelial cells of the gastrointestine undergo a rapid cell-renewal and originate from stem cells throughout the life of the organisms. Previous studies have provided a solid body of evidence to show that the epithelial cell-renewal is under the strict control of cell-cell and cell-extracellular matrix (ECM) interactions between the epithelium and the connective tissue. Especially, the microenvironment around the stem cells called "niche" is thought to play important roles in this control, and its disruption leads to diseases or disorders such as cancer in the human gastrointestine. Although understanding how the niche affects the stem cells is clinically important, its mechanisms still remain mostly unknown at the molecular level, possibly due to difficulties in the identification of the stem cells in the gastrointestine. Recent progress in cell and molecular biology is gradually beginning to shed light on some of the key signaling pathways in the cell-renewal of the intestinal epithelium, such as Wnt/T-cell factor (TCF)/beta-catenin, Notch, Sonic hedgehog (Shh)/bone morphogenetic protein (BMP) signaling pathways, which are also involved in embryonic organogenesis and/or adult carcinogenesis. At present, only fragmentary information is available on their precise functions in the intestine. Nevertheless, there is a growing body of evidence that such signaling pathways have conservative functions in the intestine throughout terrestrial vertebrates, suggesting the usefulness of experimental animals to clarify molecular mechanisms regulating epithelial cell-renewal. In this article, I review some recent findings in this field, with particular focus on our studies using the Xenopus laevis intestine, where the stem cells form the mammalian-type intestinal epithelium under the control of connective tissue during metamorphosis. This Xenopus experimental system will certainly serve as a useful model for the study of the intestinal niche, whose clarification is urgently

  18. Toll-Like Receptor 4 Expression in the Epithelium of Inflammatory Periapical Lesions.

    PubMed Central

    Leonardi, R.; Perrotta, R.E.; Musumeci, G.; Crimi, S.; dos Santos, J.N.; Rusu, M.C.; Bufo, P.; Barbato, E.; Pannone, G.

    2015-01-01

    Toll-like receptors (TLR) are essential for the innate immune response against invading pathogens and have been described in immunocompetent cells of areas affected by periapical disease. Besides initiating the inflammatory response, they also directly regulate epithelial cell proliferation and survival in a variety of settings. This study evaluates the in situ expression of TLR4 in periapical granulomas (PG) and radicular cysts, focusing on the epithelial compartment. Twenty-one periapical cysts (PC) and 10 PG were analyzed; 7 dentigerous non-inflamed follicular cyst (DC) served as control. TLR4 expression was assessed by immunohistochemistry. TLR4 immunoreaction products were detected in the epithelium of all specimens, with a higher percentage of immunostained cells in PG. Although TLR4 overexpression was detected in both PG and PC, there were differences that seemed to be related to the nature of the lesion, since in PG all epithelial cells of strands, islands and trabeculae were strongly immunoreactive for TLR4, whereas in PC only some areas of the basal and suprabasal epithelial layers were immunostained. This staining pattern is consistent with the action of TLR4: in PG it could promote formation of epithelial cell rests of Malassez and in epithelial strands and islands the enhancement of cell survival, proliferation and migration, whereas in PC TLR4 could protect the lining epithelium from extensive apoptosis. These findings go some way towards answering the intriguing question of why many epithelial strands or islands in PG and the lining epithelium of apical cysts regress after non-surgical endodontic therapy, and suggest that TLR4 plays a key role in the pathobiology of the inflammatory process related to periapical disease. PMID:26708181

  19. Quality control in microarray assessment of gene expression in human airway epithelium

    PubMed Central

    Raman, Tina; O'Connor, Timothy P; Hackett, Neil R; Wang, Wei; Harvey, Ben-Gary; Attiyeh, Marc A; Dang, David T; Teater, Matthew; Crystal, Ronald G

    2009-01-01

    Background Microarray technology provides a powerful tool for defining gene expression profiles of airway epithelium that lend insight into the pathogenesis of human airway disorders. The focus of this study was to establish rigorous quality control parameters to ensure that microarray assessment of the airway epithelium is not confounded by experimental artifact. Samples (total n = 223) of trachea, large and small airway epithelium were collected by fiberoptic bronchoscopy of 144 individuals and hybridized to Affymetrix microarrays. The pre- and post-chip quality control (QC) criteria established, included: (1) RNA quality, assessed by RNA Integrity Number (RIN) ≥ 7.0; (2) cRNA transcript integrity, assessed by signal intensity ratio of GAPDH 3' to 5' probe sets ≤ 3.0; and (3) the multi-chip normalization scaling factor ≤ 10.0. Results Of the 223 samples, all three criteria were assessed in 191; of these 184 (96.3%) passed all three criteria. For the remaining 32 samples, the RIN was not available, and only the other two criteria were used; of these 29 (90.6%) passed these two criteria. Correlation coefficients for pairwise comparisons of expression levels for 100 maintenance genes in which at least one array failed the QC criteria (average Pearson r = 0.90 ± 0.04) were significantly lower (p < 0.0001) than correlation coefficients for pairwise comparisons between arrays that passed the QC criteria (average Pearson r = 0.97 ± 0.01). Inter-array variability was significantly decreased (p < 0.0001) among samples passing the QC criteria compared with samples failing the QC criteria. Conclusion Based on the aberrant maintenance gene data generated from samples failing the established QC criteria, we propose that the QC criteria outlined in this study can accurately distinguish high quality from low quality data, and can be used to delete poor quality microarray samples before proceeding to higher-order biological analyses and interpretation. PMID:19852842

  20. Effect of acetic acid on optical coherence tomography (OCT) images of cervical epithelium.

    PubMed

    Gallwas, Julia; Stanchi, Anna; Dannecker, Christian; Ditsch, Nina; Mueller, Susanna; Mortensen, Uwe; Stepp, Herbert

    2014-11-01

    Optical coherence tomography (OCT) can be used as an adjunct to colposcopy in the identification of precancerous and cancerous cervical lesions. The purpose of this study was to investigate the effect of acetic acid on OCT imaging. OCT images were taken from unsuspicious and suspicious areas of fresh conization specimens immediately after resection and 3 and 10 min after application of 6 % acetic acid. A corresponding histology was obtained from all sites. The images taken 3 and 10 min after application of acetic acid were compared to the initial images with respect to changes in brightness, contrast, and scanning depth employing a standard nonparametric test of differences of proportions. Further, mean intensity backscattering curves were calculated from all OCT images in the histological groups CIN3, inflammation, or normal epithelium. Mean difference profiles within each of these groups were determined, reflecting the mean differences between the condition before application of acetic acid and the exposure times 3 and 10 min, respectively. According to the null hypothesis, the difference profiles do not differ from profiles fluctuating around zero in a stationary way, which implies that the profiles do not differ significantly from each other. The null hypothesis was tested employing the KPSS test. The visual analysis of 137 OCT images from 46 sites of 10 conization specimens revealed a statistically significant increase in brightness for all three groups and a statistically significant decrease in contrast for normal epithelium after 10 min. Further, an increase in scanning depth was noted for normal epithelium after 10 min and for CIN3 after 3 min. The analysis of mean intensity profiles showed an increased backscattering intensity after application of acetic acid. Acetic acid significantly affects the quality of OCT images. Overall brightness and scanning depth increase with the opposite effect regarding the image contrast. Whether the observed changes

  1. Lhx1 is required in Müllerian duct epithelium for uterine development.

    PubMed

    Huang, Cheng-Chiu; Orvis, Grant D; Kwan, Kin Ming; Behringer, Richard R

    2014-05-15

    The female reproductive tract organs of mammals, including the oviducts, uterus, cervix and upper vagina, are derived from the Müllerian ducts, a pair of epithelial tubes that form within the mesonephroi. The Müllerian ducts form in a rostral to caudal manner, guided by and dependent on the Wolffian ducts that have already formed. Experimental embryological studies indicate that caudal elongation of the Müllerian duct towards the urogenital sinus occurs in part by proliferation at the ductal tip. The molecular mechanisms that regulate the elongation of the Müllerian duct are currently unclear. Lhx1 encodes a LIM-homeodomain transcription factor that is essential for male and female reproductive tract development. Lhx1 is expressed in both the Wolffian and Müllerian ducts. Wolffian duct-specific knockout of Lhx1 results in degeneration of the Wolffian duct and consequently the non-cell-autonomous loss of the Müllerian duct. To determine the role of Lhx1 specifically in the Müllerian duct epithelium, we performed a Müllerian duct-specific knockout study using Wnt7a-Cre mice. Loss of Lhx1 in the Müllerian duct epithelium led to a block in Müllerian duct elongation and uterine hypoplasia characterized by loss of the entire endometrium (luminal and glandular epithelium and stroma) and inner circular but not the outer longitudinal muscle layer. Time-lapse imaging and molecular analyses indicate that Lhx1 acts cell autonomously to maintain ductal progenitor cells for Müllerian duct elongation. These studies identify LHX1 as the first transcription factor that is essential in the Müllerian duct epithelial progenitor cells for female reproductive tract development. Furthermore, these genetic studies demonstrate the requirement of epithelial-mesenchymal interactions for uterine tissue compartment differentiation.

  2. Repopulation of the seminiferous epithelium of the rhesus monkey after X irradiation

    SciTech Connect

    van Alphen, M.M.; van de Kant, H.J.; de Rooij, D.G.

    1988-03-01

    Repopulation of the seminiferous epithelium became evident from Day 75 postirradiation onward after doses of 0.5, 1.0, and 2.0 Gy of X rays. Cell counts in cross sections of seminiferous tubules revealed that during this repopulation the numbers of Apale (Ap) spermatogonia, Adark (Ad) spermatogonia, and B spermatogonia increased simultaneously. After 0.5 Gy the number of spermatogonia increased from approximately 10% of the control level at Day 44 to 90% at Day 200. After 1.0 and 2.0 Gy the numbers of spermatogonia increased from less than 5% at Day 44 to 70% at Days 200 and 370. The number of Ad and B spermatogonia, which are considered to be resting and differentiating spermatogonia, respectively, already had increased when the number of proliferating Ap spermatogonia was still very low. This early inactivation and differentiation of a large part of the population of Ap spermatogonia slows down repopulation of the seminiferous epithelium of the primates. By studying repopulating colonies in whole mounts of seminiferous tubules various types of colonies were found. In colonies consisting of only A spermatogonia, 40% of the A spermatogonia were found to be of the Ad type, which indicates that even before the colony had differentiated, 40% of the A spermatogonia were inactivated into Ad. Differentiating colonies were also found in which one or two generations of germ cells were missing. In some of those colonies it was found that the Ap spermatogonia did not form any B spermatogonia during one or two cycles of the seminiferous epithelium, while in other colonies all Ap spermatogonia present had differentiated into B spermatogonia. This indicates that the differentiation of Ap into B spermatogonia is a stochastic process.

  3. Global expression profiling of globose basal cells and neurogenic progression within the olfactory epithelium.

    PubMed

    Krolewski, Richard C; Packard, Adam; Schwob, James E

    2013-03-01

    Ongoing, lifelong neurogenesis maintains the neuronal population of the olfactory epithelium in the face of piecemeal neuronal turnover and restores it following wholesale loss. The molecular phenotypes corresponding to different stages along the progression from multipotent globose basal cell (GBC) progenitor to differentiated olfactory sensory neuron are poorly characterized. We used the transgenic expression of enhanced green fluorescent protein (eGFP) and cell surface markers to FACS-isolate ΔSox2-eGFP(+) GBCs, Neurog1-eGFP(+) GBCs and immature neurons, and ΔOMP-eGFP(+) mature neurons from normal adult mice. In addition, the latter two populations were also collected 3 weeks after olfactory bulb ablation, a lesion that results in persistently elevated neurogenesis. Global profiling of mRNA from the populations indicates that all stages of neurogenesis share a cohort of >2,100 genes that are upregulated compared to sustentacular cells. A further cohort of >1,200 genes are specifically upregulated in GBCs as compared to sustentacular cells and differentiated neurons. The increased rate of neurogenesis caused by olfactory bulbectomy had little effect on the transcriptional profile of the Neurog1-eGFP(+) population. In contrast, the abbreviated lifespan of ΔOMP-eGFP(+) neurons born in the absence of the bulb correlated with substantial differences in gene expression as compared to the mature neurons of the normal epithelium. Detailed examination of the specific genes upregulated in the different progenitor populations revealed that the chromatin modifying complex proteins LSD1 and coREST were expressed sequentially in upstream ΔSox2-eGFP(+) GBCs and Neurog1-eGFP(+) GBCs/immature neurons. The expression patterns of these proteins are dynamically regulated after activation of the epithelium by methyl bromide lesion. PMID:22847514

  4. A Regulatory Loop Involving PAX6, MITF, and WNT Signaling Controls Retinal Pigment Epithelium Development

    PubMed Central

    Bharti, Kapil; Gasper, Melanie; Ou, Jingxing; Brucato, Martha; Clore-Gronenborn, Katharina; Pickel, James; Arnheiter, Heinz

    2012-01-01

    The separation of the optic neuroepithelium into future retina and retinal pigment epithelium (RPE) is a critical event in early eye development in vertebrates. Here we show in mice that the transcription factor PAX6, well-known for its retina-promoting activity, also plays a crucial role in early pigment epithelium development. This role is seen, however, only in a background genetically sensitized by mutations in the pigment cell transcription factor MITF. In fact, a reduction in Pax6 gene dose exacerbates the RPE-to-retina transdifferentiation seen in embryos homozygous for an Mitf null allele, and it induces such a transdifferentiation in embryos that are either heterozygous for the Mitf null allele or homozygous for an RPE–specific hypomorphic Mitf allele generated by targeted mutation. Conversely, an increase in Pax6 gene dose interferes with transdifferentiation even in homozygous Mitf null embryos. Gene expression analyses show that, together with MITF or its paralog TFEC, PAX6 suppresses the expression of Fgf15 and Dkk3. Explant culture experiments indicate that a combination of FGF and DKK3 promote retina formation by inhibiting canonical WNT signaling and stimulating the expression of retinogenic genes, including Six6 and Vsx2. Our results demonstrate that in conjunction with Mitf/Tfec Pax6 acts as an anti-retinogenic factor, whereas in conjunction with retinogenic genes it acts as a pro-retinogenic factor. The results suggest that careful manipulation of the Pax6 regulatory circuit may facilitate the generation of retinal and pigment epithelium cells from embryonic or induced pluripotent stem cells. PMID:22792072

  5. Lhx1 is required in Müllerian duct epithelium for uterine development

    PubMed Central

    Huang, Cheng-Chiu; Orvis, Grant D.; Kwan, Kin Ming; Behringer, Richard R.

    2014-01-01

    The female reproductive tract organs of mammals, including the oviducts, uterus, cervix and upper vagina, are derived from the Müllerian ducts, a pair of epithelial tubes that form within the mesonephroi. The Müllerian ducts form in a rostral to caudal manner, guided by and dependent on the Wolffian ducts that have already formed. Experimental embryological studies indicate that caudal elongation of the Müllerian duct towards the urogenital sinus occurs in part by proliferation at the ductal tip. The molecular mechanisms that regulate the elongation of the Müllerian duct are currently unclear. Lhx1 encodes a LIM-homeodomain transcription factor that is essential for male and female reproductive tract development. Lhx1 is expressed in both the Wolffian and Müllerian ducts. Wolffian duct-specific knockout of Lhx1 results in degeneration of the Wolffian duct and consequently the non cell-autonomous loss of the Müllerian duct. To determine the role of Lhx1 specifically in the Müllerian duct epithelium, we performed a Müllerian duct-specific knockout study using Wnt7a-Cre mice. Loss of Lhx1 in the Müllerian duct epithelium led to a block in Müllerian duct elongation and uterine hypoplasia characterized by loss of the entire endometrium (luminal and glandular epithelium and stroma) and inner circular but not the outer longitudinal muscle layer. Time-lapse imaging and molecular analyses indicate that Lhx1 acts cell autonomously to maintain ductal progenitor cells for Müllerian duct elongation. These studies identify LHX1 as the first transcription factor that is essential in the Müllerian duct epithelial progenitor cells for female reproductive tract development. Furthermore, these genetic studies demonstrate the requirement of epithelial-mesenchymal interactions for uterine tissue compartment differentiation. PMID:24560999

  6. Near Equilibrium Calculus of Stem Cells in Application to the Airway Epithelium Lineage.

    PubMed

    Sun, Zheng; Plikus, Maksim V; Komarova, Natalia L

    2016-07-01

    Homeostatic maintenance of tissues is orchestrated by well tuned networks of cellular signaling. Such networks regulate, in a stochastic manner, fates of all cells within the respective lineages. Processes such as symmetric and asymmetric divisions, differentiation, de-differentiation, and death have to be controlled in a dynamic fashion, such that the cell population is maintained at a stable equilibrium, has a sufficiently low level of stochastic variation, and is capable of responding efficiently to external damage. Cellular lineages in real tissues may consist of a number of different cell types, connected by hierarchical relationships, albeit not necessarily linear, and engaged in a number of different processes. Here we develop a general mathematical methodology for near equilibrium studies of arbitrarily complex hierarchical cell populations, under regulation by a control network. This methodology allows us to (1) determine stability properties of the network, (2) calculate the stochastic variance, and (3) predict how different control mechanisms affect stability and robustness of the system. We demonstrate the versatility of this tool by using the example of the airway epithelium lineage. Recent research shows that airway epithelium stem cells divide mostly asymmetrically, while the so-called secretory cells divide predominantly symmetrically. It further provides quantitative data on the recovery dynamics of the airway epithelium, which can include secretory cell de-differentiation. Using our new methodology, we demonstrate that while a number of regulatory networks can be compatible with the observed recovery behavior, the observed division patterns of cells are the most optimal from the viewpoint of homeostatic lineage stability and minimizing the variation of the cell population size. This not only explains the observed yet poorly understood features of airway tissue architecture, but also helps to deduce the information on the still largely hypothetical

  7. Reflex-mediated desquamation of bronchiolar epithelium in guinea pigs exposed acutely to sulfuric acid aerosol.

    PubMed Central

    Brownstein, D. G.

    1980-01-01

    Terminal conducting airways are known to be vulnerable to direct injury by a variety of noxious aerosols. Sulfuric acid aerosol, a by-product of fossil fuel combustion, produces desquamation of terminal bronchiolar epithelium in guinea pigs that is believed to result from direct deep lung irritation, an effect separable from reflex airway constriction induced by sulfuric acid. To characterize desquamation of bronchiolar epithelium, 20 guinea pigs were exposed to 32.6 mg/cu m sulfuric acid aerosol with a mass median aerodynamic diameter of 1.0 micron for 4 hours. The guinea pigs were killed upon termination of the exposure, or 24 hours later, and airway alterations were evaluated by light and transmission electron microscopy. To test whether the development of bronchiolar epithelial desquamation is independent of reflex airway constriction, 24 guinea pigs were exposed to an identical aerosol for 4 hours after pretreating half with 5 mg/kg atropine sulfate intraperitoneally to inhibit airway constriction. Sulfuric acid produced diffuse pulmonary hyperinflation with areas of consolidation and atelectasis. Epithelial desquamation occurred in airways supplying regions of developing atelectasis and was most extensive in terminal bronchioles. Parasympathetic effector blockade with atropine eliminated epithelial desquamation. These results indicate that sulfuric acid-produced desquamation of terminal bronchiolar epithelium is not separable from reflex airway constriction and that terminal conducting airways are vulnerable not only to direct injury by noxious aerosols but also to indirect, reflex-mediated injury. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:7361847

  8. Lipoxin A4 inhibits immune cell binding to salivary epithelium and vascular endothelium

    PubMed Central

    Chinthamani, Sreedevi; Odusanwo, Olutayo; Mondal, Nandini; Nelson, Joel; Neelamegham, Sriram

    2012-01-01

    Lipoxins are formed by leukocytes during cell-cell interactions with epithelial or endothelial cells. Native lipoxin A4 (LXA4) binds to the G protein-coupled lipoxin receptors formyl peptide receptor 2 (FPR2)/ALX and CysLT1. Furthermore, LXA4 inhibits recruitment of neutrophils, by attenuating chemotaxis, adhesion, and transmigration across vascular endothelial cells. LXA4 thus appears to serve as an endogenous “stop signal” for immune cell-mediated tissue injury (Serhan CN; Annu Rev Immunol 25: 101–137, 2007). The role of LXA4 has not been addressed in salivary epithelium, and little is known about its effects on vascular endothelium. Here, we determined that interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) receptor activation in vascular endothelium and salivary epithelium upregulated the expression of adhesion molecules that facilitates the binding of immune cells. We hypothesize that the activation of the ALX/FPR2 and/or CysLT1 receptors by LXA4 decreases this cytokine-mediated upregulation of cell adhesion molecules that enhance lymphocyte binding to both the vascular endothelium and salivary epithelium. In agreement with this hypothesis, we observed that nanomolar concentrations of LXA4 blocked IL-1β- and TNF-α-mediated upregulation of E-selectin and intercellular cell adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells (HUVECs). Binding of Jurkat cells to stimulated HUVECs was abrogated by LXA4. Furthermore, LXA4 preincubation with human submandibular gland cell line (HSG) also blocked TNF-α-mediated upregulation of vascular cell adhesion molecule-1 (VCAM-1) in these cells, and it reduced lymphocyte adhesion. These findings suggest that ALX/FPR2 and/or CysLT1 receptor activation in endothelial and epithelial cells blocks cytokine-induced adhesion molecule expression and consequent binding of lymphocytes, a critical event in the pathogenesis of Sjögren's syndrome (SS). PMID:22205391

  9. [Electron microscopic study of the intestinal epithelium of Saccoglossus mereschkowskii (Enteropneusta, Hemichordata)].

    PubMed

    Stoliarova, M V

    2011-01-01

    Epithelium of the hepatic region of the intestine in Saccoglossus mereschkowskii, a representative of enteropneusts (Enteropneusta, Hemichordata) standing at the base of Chordata, has been investigated using electron microscope. The ultrastructure of ciliated and granular epithelial cells, elements of the intraepithelial nerve layer, and intercellular junctions have been characterized. The data concerning details of the organization of the ciliary apparatus and rootlets system are presented. It is justified the presence of complicated supporting construction of cilia which performs a mechanical stabilizing function and possibly also provide synchronization of ciliary movements. The presence of cilia with two centrioles is considered as an adaptation to high functional load on ciliary apparatus. Well developed bundles of myofilaments are found in the cytoplasm of the basal portions of ciliary cells that characterizes these cells as myoepithelial. The features indicating the role of ciliary cells in absorption are described. The capability of these cells to balloon-like secretion is considered. Data on the accumulation of food reserves in the form of lipid droplets and glycogen in the cell cytoplasm are presented. Ciliated cells are characterized by their function as ciliated secretory-absorptive myoepithelial cells. Based on the location of secretory granules both in the apical and basal portions of granular cells, an exocrine-endocrine function of these cells has been suggested. Typical endocrine cells in the intestinal epithelium of S. mereschkowskii are absent. Several types of granules in the nerve fibers cytoplasm are described. Junctions between the nerve fibers and basal portions of ciliary and granular epithelial cells are found. Nerve regulation of contractile and secretory functions of epithelial cells is supposed. The presence of the regulatory nerve-endocrine system that includes receptor cells of open type, secretory endocrine-like cells and nerve

  10. Dendrimer Nanocarriers for Transport Modulation Across Models of the Pulmonary Epithelium

    PubMed Central

    2015-01-01

    The purpose of this study was to determine the effect of PEGylation on the interaction of poly(amidoamine) (PAMAM) dendrimer nanocarriers (DNCs) with in vitro and in vivo models of the pulmonary epithelium. Generation-3 PAMAM dendrimers with varying surface densities of PEG 1000 Da were synthesized and characterized. The results revealed that the apical to basolateral transport of DNCs across polarized Calu-3 monolayers increases with an increase in PEG surface density. DNC having the greatest number of PEG groups (n = 25) on their surface traversed at a rate 10-fold greater than its non-PEGylated counterpart, in spite of their larger size. This behavior was attributed to a significant reduction in charge density upon PEGylation. We also observed that PEGylation can be used to modulate cellular internalization. The total uptake of PEG-free DNC into polarized Calu-3 monolayers was 12% (w/w) vs 2% (w/w) for that with 25 PEGs. Polarization is also shown to be of great relevance in studying this in vitro model of the lung epithelium. The rate of absorption of DNCs administered to mice lungs increased dramatically when conjugated with 25 PEG groups, thus supporting the in vitro results. The exposure obtained for the DNC with 25PEG was determined to be very high, with peak plasma concentrations reaching 5 μg·mL–1 within 3 h. The combined in vitro and in vivo results shown here demonstrate that PEGylation can be potentially used to modulate the internalization and transport of DNCs across the pulmonary epithelium. Modified dendrimers thereby may serve as a valuable platform that can be tailored to target the lung tissue for treating local diseases, or the circulation, using the lung as pathway to the bloodstream, for systemic delivery. PMID:25455560

  11. Dendrimer nanocarriers for transport modulation across models of the pulmonary epithelium.

    PubMed

    Bharatwaj, Balaji; Mohammad, Abdul Khader; Dimovski, Radovan; Cassio, Fernando L; Bazito, Reinaldo C; Conti, Denise; Fu, Qiang; Reineke, Joshua; da Rocha, Sandro R P

    2015-03-01

    The purpose of this study was to determine the effect of PEGylation on the interaction of poly(amidoamine) (PAMAM) dendrimer nanocarriers (DNCs) with in vitro and in vivo models of the pulmonary epithelium. Generation-3 PAMAM dendrimers with varying surface densities of PEG 1000 Da were synthesized and characterized. The results revealed that the apical to basolateral transport of DNCs across polarized Calu-3 monolayers increases with an increase in PEG surface density. DNC having the greatest number of PEG groups (n = 25) on their surface traversed at a rate 10-fold greater than its non-PEGylated counterpart, in spite of their larger size. This behavior was attributed to a significant reduction in charge density upon PEGylation. We also observed that PEGylation can be used to modulate cellular internalization. The total uptake of PEG-free DNC into polarized Calu-3 monolayers was 12% (w/w) vs 2% (w/w) for that with 25 PEGs. Polarization is also shown to be of great relevance in studying this in vitro model of the lung epithelium. The rate of absorption of DNCs administered to mice lungs increased dramatically when conjugated with 25 PEG groups, thus supporting the in vitro results. The exposure obtained for the DNC with 25PEG was determined to be very high, with peak plasma concentrations reaching 5 μg·mL(-1) within 3 h. The combined in vitro and in vivo results shown here demonstrate that PEGylation can be potentially used to modulate the internalization and transport of DNCs across the pulmonary epithelium. Modified dendrimers thereby may serve as a valuable platform that can be tailored to target the lung tissue for treating local diseases, or the circulation, using the lung as pathway to the bloodstream, for systemic delivery. PMID:25455560

  12. Early survival factor deprivation in the olfactory epithelium enhances activity-driven survival

    PubMed Central

    François, Adrien; Laziz, Iman; Rimbaud, Stéphanie; Grebert, Denise; Durieux, Didier; Pajot-Augy, Edith; Meunier, Nicolas

    2013-01-01

    The neuronal olfactory epithelium undergoes permanent renewal because of environmental aggression. This renewal is partly regulated by factors modulating the level of neuronal apoptosis. Among them, we had previously characterized endothelin as neuroprotective. In this study, we explored the effect of cell survival factor deprivation in the olfactory epithelium by intranasal delivery of endothelin receptors antagonists to rat pups. This treatment induced an overall increase of apoptosis in the olfactory epithelium. The responses to odorants recorded by electroolfactogram were decreased in treated animal, a result consistent with a loss of olfactory sensory neurons (OSNs). However, the treated animal performed better in an olfactory orientation test based on maternal odor compared to non-treated littermates. This improved performance could be due to activity-dependent neuronal survival of OSNs in the context of increased apoptosis level. In order to demonstrate it, we odorized pups with octanal, a known ligand for the rI7 olfactory receptor (Olr226). We quantified the number of OSN expressing rI7 by RT-qPCR and whole mount in situ hybridization. While this number was reduced by the survival factor removal treatment, this reduction was abolished by the presence of its ligand. This improved survival was optimal for low concentration of odorant and was specific for rI7-expressing OSNs. Meanwhile, the number of rI7-expressing OSNs was not affected by the odorization in non-treated littermates; showing that the activity-dependant survival of OSNs did not affect the OSN population during the 10 days of odorization in control conditions. Overall, our study shows that when apoptosis is promoted in the olfactory mucosa, the activity-dependent neuronal plasticity allows faster tuning of the olfactory sensory neuron population toward detection of environmental odorants. PMID:24399931

  13. Staphylococcus aureus triggers nitric oxide production in human upper airway epithelium

    PubMed Central

    Carey, Ryan M.; Workman, Alan D.; Chen, Bei; Adappa, Nithin D.; Palmer, James N.; Kennedy, David W.; Lee, Robert J.; Cohen, Noam A.

    2016-01-01

    Background Nitric oxide (NO) is an important antibacterial defense molecule produced by upper airway (sinonasal) epithelial cells. We previously showed that a bitter taste receptor expressed in airway epithelium detects quorum-sensing molecules secreted by Gram-negative bacteria and subsequently triggers bactericidal NO production. We hypothesized that the upper airway epithelium may also be able to detect the Gram-positive aerobe Staphylococcus aureus and mount an NO response. Methods Human sinonasal air-liquid interface (ALI) cultures were treated with methicillin-resistant S. aureus (MRSA)-conditioned medium (CM), and NO production was measured using fluorescence imaging. Inhibitors of bitter taste receptor signaling were used to pharmacologically determine if this pathway was involved in the production of NO. Results A low-molecular-weight, heat, and protease-stabile product found in MRSA CM induced differential, NO synthase (NOS)-mediated NO production. This response varied markedly between individual patients. The MRSA-stimulated NO production was not dependent on 2 important components of bitter taste signaling: phospholipase C isoform β-2 or the transient receptor potential melastatin isoform 5 (TRPM5) ion channel. Conclusion This study shows that a S. aureus product elicits an NO-mediated innate defense response in human upper airway epithelium. The active bacterial product is likely a small, nonpeptide molecule that triggers a pathway independent of bitter taste receptors. Patient variation in the NO response to MRSA product(s), potentially due to genetic differences, might play a role in pathophysiology of Gram-positive upper respiratory infections and/or pathogenesis of chronic rhinosinusitis. PMID:26097237

  14. Localization and Expression of Zonula Occludins-1 in the Rabbit Corneal Epithelium following Exposure to Benzalkonium Chloride

    PubMed Central

    Zhang, Zhenhao; Chen, Lelei; Xie, Hui; Dong, Nuo; Chen, Yongxiong; Liu, Zuguo

    2012-01-01

    Preservatives are a major component of the ophthalmic preparations in multi-dose bottles. The purpose of this study was to investigate the acute effect of benzalkonium chloride (BAC), a common preservative used in ophthalmic preparations, on the localization and expression of zonula occludens (ZO)-1 in the rabbit corneal epithelium in vivo. BAC at 0.005%, 0.01%, or 0.02% was topically applied to one eye each of albino rabbits at 5 min intervals for a total of 3 times. The contralateral untreated eyes served as controls. The following clinical indications were evaluated: Schirmer test, tear break-up time (BUT), fluorescein and rose Bengal staining. The structure of central cornea was examined by in vivo confocal microscopy, and the corneal barrier function was evaluated by measurement of corneal transepithelial electrical resistance and permeability to carboxy fluorescein. Whole mount corneas were analyzed by using fluorescence confocal microscopy for the presence of ZO-1, 2, occludin, claudin-1, Ki67 and cell apoptosis in the epithelium. The expression of ZO-1 in the corneal epithelium was also examined by western blot and reverse transcription-polymerase chain reaction analyses. Exposure to BAC resulted in higher rose Bengal staining scores while no significant changes in BUT, Schirmer and corneal florescein scores. It also induced corneal epithelial cell damage, dispersion of ZO-1 and ZO-2 from their normal locus at the superficial layer and disruption of epithelial barrier function. However, the amounts of ZO-1 mRNA and protein in the corneal epithelium were not affected by BAC treatment. Exposure to BAC can quickly impair the corneal epithelium without tear deficiency. BAC disrupts the tight junctions of corneal epithelium between superficial cells in the rabbit corneal epithelium in vivo. PMID:22815857

  15. A study of the rete testis epithelium in several wild birds.

    PubMed

    Barker, S G; Kendall, M D

    1984-01-01

    Material from six wild non-breeding starlings (Sturnus vulgaris), twelve adult wild quelea (Quelea quelea) in prenuptial, full and post-breeding condition and one wild puffin (Fratercula arctica) was examined by light and electron microscopy. Contrary to previous accounts of avian material, the epithelium of the rete testis was composed of a mixture of numerous non-ciliated and fewer ciliated cells. Both cell types contained many inclusions in the cytoplasm all of which indicated that the cells could modify the luminal contents. All rete testis epithelial cells showed a strong reaction with stains for alkaline phosphatase. PMID:6706832

  16. Effects of ozone and endotoxin coexposure on rat airway epithelium: potentiation of toxicant-induced alterations.

    PubMed Central

    Wagner, J G; Hotchkiss, J A; Harkema, J R

    2001-01-01

    Tropospheric ozone is the major oxidizing component in photochemical smog and is one of the most pervasive problems to human health of the criteria air pollutants for which the National Ambient Air Quality Standards have been designated by the Clean Air Act. Although many adverse health effects of ozone exposure have been documented in both humans and laboratory animals, controversy surrounds the establishment and implementation of ozone standards set forth by the U.S. Environmental Protection Agency. Because people are commonly exposed to more than one air pollutant at a time, studies that examine coexposures to airborne materials may be more relevant for assessing their risks to human health. Airborne biogenic substances such as pollens, spores, and bacterial products are ubiquitous in the environment, and when inhaled can cause adverse respiratory symptoms. One such biogenic agent, bacterial endotoxin, is a potent stimulus of airway inflammation and is a ubiquitous airborne contaminant commonly found in domestic, agricultural, and industrial settings. Little is known about the interaction of exposures to biogenic substances and criteria air pollutants such as ozone. In the last few years we have performed a series of studies in rodents that examined the biologic responses of the respiratory epithelium after airway exposures to both endotoxin and ozone. When exposed to ozone (0.5 ppm 8 hr/day for 3 days), Fischer rats develop lesions in the nasal transitional epithelium, whereas intranasal instillation of endotoxin (20 microg) elicits epithelial lesions in the respiratory epithelium of the nose and conducting airways. Our studies were designed to examine how exposure to one toxicant may affect the airway epithelial lesions induced by the other toxicant. We investigated the potential role of acute inflammation in the enhancement of airway epithelial lesions after exposure of these two toxicants in neutrophil-sufficient and neutrophil-deficient rodents. A summary

  17. Congenital simple hamartoma of the retinal pigment epithelium: a case report.

    PubMed

    Thorell, Mariana Rossi; Kniggendorf, Vinicius Ferreira; Arana, Luis Augusto; Grandinetti, Alexandre Achille

    2014-04-01

    We report the case of a 56-year-old woman who presented for a routine ophthalmological examination without visual symptoms and had a unilateral black retinal lesion that was detected by clinical examination. Fluorescein angiography and optical coherence tomography findings were compatible with a congenital simple hamartoma of the retinal pigment epithelium. It is very important to detect this tumor and differentiate it from other pigmented fundus lesions that can compromise visual function or result in systemic conditions such as those caused by malignant tumors. PMID:25076477

  18. HIV Impairs Lung Epithelial Integrity and Enters the Epithelium to Promote Chronic Lung Inflammation.

    PubMed

    Brune, Kieran A; Ferreira, Fernanda; Mandke, Pooja; Chau, Eric; Aggarwal, Neil R; D'Alessio, Franco R; Lambert, Allison A; Kirk, Gregory; Blankson, Joel; Drummond, M Bradley; Tsibris, Athe M; Sidhaye, Venkataramana K

    2016-01-01

    Several clinical studies show that individuals with HIV are at an increased risk for worsened lung function and for the development of COPD, although the mechanism underlying this increased susceptibility is poorly understood. The airway epithelium, situated at the interface between the external environment and the lung parenchyma, acts as a physical and immunological barrier that secretes mucins and cytokines in response to noxious stimuli which can contribute to the pathobiology of chronic obstructive pulmonary disease (COPD). We sought to determine the effects of HIV on the lung epithelium. We grew primary normal human bronchial epithelial (NHBE) cells and primary lung epithelial cells isolated from bronchial brushings of patients to confluence and allowed them to differentiate at an air- liquid interface (ALI) to assess the effects of HIV on the lung epithelium. We assessed changes in monolayer permeability as well as the expression of E-cadherin and inflammatory modulators to determine the effect of HIV on the lung epithelium. We measured E-cadherin protein abundance in patients with HIV compared to normal controls. Cell associated HIV RNA and DNA were quantified and the p24 viral antigen was measured in culture supernatant. Surprisingly, X4, not R5, tropic virus decreased expression of E-cadherin and increased monolayer permeability. While there was some transcriptional regulation of E-cadherin, there was significant increase in lysosome-mediated protein degradation in cells exposed to X4 tropic HIV. Interaction with CXCR4 and viral fusion with the epithelial cell were required to induce the epithelial changes. X4 tropic virus was able to enter the airway epithelial cells but not replicate in these cells, while R5 tropic viruses did not enter the epithelial cells. Significantly, X4 tropic HIV induced the expression of intercellular adhesion molecule-1 (ICAM-1) and activated extracellular signal-regulated kinase (ERK). We demonstrate that HIV can enter airway

  19. Effects of ozone and endotoxin coexposure on rat airway epithelium: potentiation of toxicant-induced alterations.

    PubMed

    Wagner, J G; Hotchkiss, J A; Harkema, J R

    2001-08-01

    Tropospheric ozone is the major oxidizing component in photochemical smog and is one of the most pervasive problems to human health of the criteria air pollutants for which the National Ambient Air Quality Standards have been designated by the Clean Air Act. Although many adverse health effects of ozone exposure have been documented in both humans and laboratory animals, controversy surrounds the establishment and implementation of ozone standards set forth by the U.S. Environmental Protection Agency. Because people are commonly exposed to more than one air pollutant at a time, studies that examine coexposures to airborne materials may be more relevant for assessing their risks to human health. Airborne biogenic substances such as pollens, spores, and bacterial products are ubiquitous in the environment, and when inhaled can cause adverse respiratory symptoms. One such biogenic agent, bacterial endotoxin, is a potent stimulus of airway inflammation and is a ubiquitous airborne contaminant commonly found in domestic, agricultural, and industrial settings. Little is known about the interaction of exposures to biogenic substances and criteria air pollutants such as ozone. In the last few years we have performed a series of studies in rodents that examined the biologic responses of the respiratory epithelium after airway exposures to both endotoxin and ozone. When exposed to ozone (0.5 ppm 8 hr/day for 3 days), Fischer rats develop lesions in the nasal transitional epithelium, whereas intranasal instillation of endotoxin (20 microg) elicits epithelial lesions in the respiratory epithelium of the nose and conducting airways. Our studies were designed to examine how exposure to one toxicant may affect the airway epithelial lesions induced by the other toxicant. We investigated the potential role of acute inflammation in the enhancement of airway epithelial lesions after exposure of these two toxicants in neutrophil-sufficient and neutrophil-deficient rodents. A summary

  20. Glycan profile of oviductal isthmus epithelium in normal and superovulated ewes.

    PubMed

    Desantis, Salvatore; Accogli, Gianluca; Silvestre, Fabio; Binetti, Francesco; Cox, Sharon Natasha; Roscino, Mariateresa; Caira, Michele; Lacalandra, Giovanni Michele

    2016-04-01

    Glycans of oviductal isthmus are implicated in sperm-isthmus interaction, sperm storage, survival, and capacitation. Isthmus morphology and glycoprotein production are controlled by sex steroids, which could be responsible for alterations of some reproductive events in the superovulated ewes (SE). In this study, the oviductal isthmus epithelium was evaluated in normal and in SE using morphologic and lectin histochemical analysis. The epithelium of normal isthmi was significantly taller in folds than in crypts, whereas it significantly decreased in the folds of SE. Nonciliated cells (NCs) from normal, showed apical blebs revealing apocrine secretory activity, which was missing in SE. The quantitative analysis of lectin staining revealed higher Con A, DBA, and PNA reactivity but lower affinity to KOH-sialidase- (Ks)WGA, GSA II, LTA, UEA I, SBA, GSA I-B4, RCA120, KsPNA, MAL II, SNA in control isthmi compared with superovulated ones. The NCs apical blebs showed terminal fucose (Fuc), N-acetylgalactosamine (GalNAc), galactose (Gal), lactosamine, and O- and N-sialoglycans. In normal isthmi, the luminal surface of NCs and ciliated cells expressed Fuc, highly mannosilated N-glycans terminating with lactosamine as well as O-glycans ending with N-acetylglucosamine (GlcNAc) and GalNAc. Moreover, NCs microvilli contained Gal and α2-3-linked sialic acids. In SE, the luminal surface lacked Gal and GalNAcα1, 3(LFucα1,2)Galβ1,3/4GlcNAcβ1, whereas it was enriched with Fuc in the folds and with α2-3sialo-mucins both in crypts and in folds. The apical surface showed additional O- and N-linked sialoglycans in NCs and αGal in the cilia, which expressed α2-6-linked sialic acid only in the folds. The cytoplasm of control NCs showed highly mannosilated N-glycans throughout the epithelium and GlcNAc in the folds. After superovulation treatment, NCs expressed cytoplasmic terminal Fuc, βGalNAc, lactosamine, α2-3-, and α2-6-linked sialic acids in the folds. The cytoplasm of normal

  1. Transformation of the human ovarian surface epithelium with genetically defined elements.

    PubMed

    Shan, Weiwei; Liu, Jinsong

    2013-01-01

    Success in in vitro transformation of primary cells from the human ovarian surface epithelium (OSE) has provided significant insight to the study of human ovarian cancer. Here, we describe the method used to immortalize and transform OSE by serial introduction of viral and nonviral genetic elements as well as to test the tumorigenicity of hence established cell lines in appropriate animal models. Successful transformation of OSE cells in the laboratory is of critical significance to the study of ovarian cancer. It not only allows for testing the roles of numerous potential oncogenes in initiating and promoting human ovarian cancer but provides a convenient tool to comprehensively dissect ovarian tumorigenesis in the laboratory.

  2. The respiratory epithelium of the lung in the green turtle (Chelonia mydas L.).

    PubMed Central

    Solomon, S E; Purton, M

    1984-01-01

    The chelonian lung exhibits reptilian, mammalian and avian features. The respiratory epithelium is typically vertebrate, i.e. pseudostratified columnar with cilia; gaseous exchange areas appear at all levels from the respiratory bronchi down to the alveoli. The latter are invested with a capillary network and both type I and type II cells are present. The possible functional significance of the distribution of collagen, elastic tissue, cartilage and smooth muscle is discussed. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 PMID:6490523

  3. Reconstituted Human Upper Airway Epithelium as 3-D In Vitro Model for Nasal Polyposis

    PubMed Central

    de Borja Callejas, Francisco; Martínez-Antón, Asunción; Alobid, Isam; Fuentes, Mireya; Cortijo, Julio; Picado, César

    2014-01-01

    Background Primary human airway epithelial cells cultured in an air-liquid interface (ALI) develop a well-differentiated epithelium. However, neither characterization of mucociliar differentiation overtime nor the inflammatory function of reconstituted nasal polyp (NP) epithelia have been described. Objectives 1st) To develop and characterize the mucociliar differentiation overtime of human epithelial cells of chronic rhinosinusitis with nasal polyps (CRSwNP) in ALI culture system; 2nd) To corroborate that 3D in vitro model of NP reconstituted epithelium maintains, compared to control nasal mucosa (NM), an inflammatory function. Methods Epithelial cells were obtained from 9 NP and 7 control NM, and differentiated in ALI culture for 28 days. Mucociliary differentiation was characterized at different times (0, 7, 14, 21, and 28 days) using ultrastructure analysis by electron microscopy; ΔNp63 (basal stem/progenitor cell), β-tubulin IV (cilia), and MUC5AC (goblet cell) expression by immunocytochemistry; and mucous (MUC5AC, MUC5B) and serous (Lactoferrin) secretion by ELISA. Inflammatory function of ALI cultures (at days 0, 14, and 28) through cytokine (IL-8, IL-1β, IL-6, IL-10, TNF-α, and IL-12p70) and chemokine (RANTES, MIG, MCP-1, IP-10, eotaxin-1, and GM-CSF) production was analysed by CBA (Cytometric Bead Array). Results In both NP and control NM ALI cultures, pseudostratified epithelium with ciliated, mucus-secreting, and basal cells were observed by electron microscopy at days 14 and 28. Displaying epithelial cell re-differentation, β-tubulin IV and MUC5AC positive cells increased, while ΔNp63 positive cells decreased overtime. No significant differences were found overtime in MUC5AC, MUC5B, and lactoferrin secretions between both ALI cultures. IL-8 and GM-CSF were significantly increased in NP compared to control NM regenerated epithelia. Conclusion Reconstituted epithelia from human NP epithelial cells cultured in ALI system provides a 3D in vitro model

  4. Cell Death and Inflammatory Bowel Diseases: Apoptosis, Necrosis, and Autophagy in the Intestinal Epithelium

    PubMed Central

    2014-01-01

    Cell death mechanisms have been associated with the development of inflammatory bowel diseases in humans and mice. Recent studies suggested that a complex crosstalk between autophagy/apoptosis, microbe sensing, and enhanced endoplasmic reticulum stress in the epithelium could play a critical role in these diseases. In addition, necroptosis, a relatively novel programmed necrosis-like pathway associated with TNF receptor activation, seems to be also present in the pathogenesis of Crohn's disease and in specific animal models for intestinal inflammation. This review attempts to cover new data related to cell death mechanisms and inflammatory bowel diseases. PMID:25126549

  5. Spatial variation in response to odorants on the rat olfactory epithelium.

    PubMed

    Edwards, D A; Mather, R A; Dodd, G H

    1988-03-15

    We have measured the electro-olfactogram produced by four odorants, nicotine, i-pentyl acetate, i-pentanoic acid and cineole from twelve positions on an in vitro preparation of rat olfactory tissue. Each odorant shows a different pattern of response over the twelve positions which can be explained by differences in olfactory receptor populations between regions of the rat olfactory epithelium. The result for nicotine is further evidence that there are olfactory receptors which are stimulated by nicotine when it is presented as a vapour. PMID:3350129

  6. Black Psychologists Discuss Behavior Modification.

    ERIC Educational Resources Information Center

    Bardo, Harold R.; And Others

    The primary purpose of this paper is to discuss reasons why blacks should be concerned and actively involved with practices in behavior modification. The concern is that as these techniques are refined it becomes more important to be sure blacks should be involved at all levels of the application of these procedures when other blacks are subjects…

  7. Changing Attitudes Through Behavior Modification.

    ERIC Educational Resources Information Center

    Whipple, W. Scott

    This article describes the philosophy and methods used by the staff at the Granite Alternative School in changing student attitudes through behavior modification. The students involved all have a failure syndrome or low self-image, and are dropouts from traditional high schools. Among the techniques used are: (1) reinforcing good behavior (praise…

  8. Behavior Modification: The Human Effort.

    ERIC Educational Resources Information Center

    Bradfield, Robert H., Ed.

    To present the ideas and research of outstanding behaviorists which is directly related to the education of children, the authors tried to include a diverse group of educational situations. Two articles give an overview of behavior modification, while five educational applications are discussed. They concern learning problems, language…

  9. Plasma surface modification of polymers

    NASA Technical Reports Server (NTRS)

    Hirotsu, T.

    1980-01-01

    Thin plasma polymerization films are discussed from the viewpoint of simplicity in production stages. The application of selective, absorbent films and films used in selective permeability was tested. The types of surface modification of polymers discussed are: (1) plasma etching, (2) surface coating by plasma polymerized thin films, and (3) plasma activation surface graft polymerization.

  10. Demonstrating Allotropic Modifications of Sulfur.

    ERIC Educational Resources Information Center

    McCarty, Jillian L.; Dragojlovic, Veljko

    2002-01-01

    Shows how a common demonstration that consists of slowly heating sulfur powder in a test tube to illustrate sulfur's allotropic modifications can convince students of conclusions about the moon Io which they often find surprising. Describes the demonstration in full. (Author/MM)

  11. Carbohydrate post-glycosylational modifications

    PubMed Central

    Yu, Hai; Chen, Xi

    2008-01-01

    Carbohydrate modification is a common phenomenon in nature. Many carbohydrate modifications such as some epimerization, O-acetylation, O-sulfation, O-methylation, N-deacetylation, and N-sulfation, take place after the formation of oligosaccharide or polysaccharide backbones. These modifications can be categorized as carbohydrate post-glycosylational modifications (PGMs). Carbohydrate PGMs further extend the complexity of the structures and the synthesis of carbohydrates and glycoconjugates. They also increase the capacity of the biological information that can be controlled by finely tuning the structures of carbohydrates. Developing efficient methods to obtain structurally defined naturally occurring oligosaccharides, polysaccharides, and glycoconjugates with carbohydrate PGMs is essential for understanding the biological significance of carbohydrate PGMs. Combine with high-throughput screening methods, synthetic carbohydrates with PGMs are invaluable probes in structure-activity relationship studies. We illustrate here several classes of carbohydrates with PGMs and their applications. Recent progress in chemical, enzymatic, and chemoenzymatic syntheses of these carbohydrates and their derivatives are also presented. PMID:17340000

  12. Behavior Modification in Marriage Counseling

    ERIC Educational Resources Information Center

    Baird, Emily; Redfering, David L.

    1975-01-01

    The spouses were counseled jointly with a cognitive approach and separately with behavior modification techniques for the husband's obesity and the wife's lack of affective verbalization. After eight weeks, the husband had lost thirty pounds and the wife's affective language had increased markedly. (Author)

  13. Liganded thyroid hormone receptor induces nucleosome removal and histone modifications to activate transcription during larval intestinal cell death and adult stem cell development.

    PubMed

    Matsuura, Kazuo; Fujimoto, Kenta; Fu, Liezhen; Shi, Yun-Bo

    2012-02-01

    Thyroid hormone (T(3)) plays an important role in regulating multiple cellular and metabolic processes, including cell proliferation, cell death, and energy metabolism, in vertebrates. Dysregulation of T(3) signaling results in developmental abnormalities, metabolic defects, and even cancer. We used T(3)-dependent Xenopus metamorphosis as a model to study how T(3) regulates transcription during vertebrate development. T(3) exerts its metamorphic effects through T(3) receptors (TR). TR recruits, in a T(3)-dependent manner, cofactor complexes that can carry out chromatin remodeling/histone modifications. Whether and how histone modifications change upon gene regulation by TR during vertebrate development is largely unknown. Here we analyzed histone modifications at T(3) target genes during intestinal metamorphosis, a process that involves essentially total apoptotic degeneration of the simple larval epithelium and de novo development of the adult epithelial stem cells, followed by their proliferation and differentiation into the complex adult epithelium. We demonstrated for the first time in vivo during vertebrate development that TR induces the removal of core histones at the promoter region and the recruitment of RNA polymerase. Furthermore, a number of histone activation and repression marks have been defined based on correlations with mRNA levels in cell cultures. Most but not all correlate with gene expression induced by liganded TR during development, suggesting that tissue and developmental context influences the roles of histone modifications in gene regulation. Our findings provide important mechanistic insights on how chromatin remodeling affects developmental gene regulation in vivo.

  14. The glucagon-like peptide 2 receptor is expressed in enteric neurons and not in the epithelium of the intestine.

    PubMed

    Pedersen, Jens; Pedersen, Nis B; Brix, Sophie W; Grunddal, Kaare Villum; Rosenkilde, Mette M; Hartmann, Bolette; Ørskov, Cathrine; Poulsen, Steen S; Holst, Jens J

    2015-05-01

    Glucagon-like peptide 2 (GLP-2) is a potent intestinotrophic growth factor with therapeutic potential in the treatment of intestinal deficiencies. It has recently been approved for the treatment of short bowel syndrome. The effects of GLP-2 are mediated by specific binding of the hormone to the GLP-2 receptor (GLP-2R) which was cloned in 1999. However, consensus about the exact receptor localization in the intestine has never been established. By physical, chemical and enzymatic tissue fragmentation, we were able to divide rat jejunum into different compartments consisting of: (1) epithelium alone, (2) mucosa with lamina propria and epithelium, (3) the external muscle coat including myenteric plexus, (4) a compartment enriched for the myenteric plexus and (5) intestine without epithelium. Expression of Glp2r; chromogranin A; tubulin, beta 3; actin, gamma 2, smooth muscle, enteric and glial fibrillary acidic protein in these isolated tissue fractions was quantified with qRT-PCR. Expression of the Glp2r was confined to compartments containing enteric neurons and receptor expression was absent in the epithelium. Our findings provide evidence for the expression of the GLP-2R in intestinal compartments rich in enteric neurons and, importantly they exclude significant expression in the epithelium of rat jejunal mucosa.

  15. Smoking-induced CXCL14 expression in the human airway epithelium links chronic obstructive pulmonary disease to lung cancer.

    PubMed

    Shaykhiev, Renat; Sackrowitz, Rachel; Fukui, Tomoya; Zuo, Wu-Lin; Chao, Ion Wa; Strulovici-Barel, Yael; Downey, Robert J; Crystal, Ronald G

    2013-09-01

    CXCL14, a recently described epithelial cytokine, plays putative multiple roles in inflammation and carcinogenesis. In the context that chronic obstructive pulmonary disease (COPD) and lung cancer are both smoking-related disorders associated with airway epithelial disorder and inflammation, we hypothesized that the airway epithelium responds to cigarette smoking with altered CXCL14 gene expression, contributing to the disease-relevant phenotype. Using genome-wide microarrays with subsequent immunohistochemical analysis, the data demonstrate that the expression of CXCL14 is up-regulated in the airway epithelium of healthy smokers and further increased in COPD smokers, especially within hyperplastic/metaplastic lesions, in association with multiple genes relevant to epithelial structural integrity and cancer. In vitro experiments revealed that the expression of CXCL14 is induced in the differentiated airway epithelium by cigarette smoke extract, and that epidermal growth factor mediates CXCL14 up-regulation in the airway epithelium through its effects on the basal stem/progenitor cell population. Analyses of two independent lung cancer cohorts revealed a dramatic up-regulation of CXCL14 expression in adenocarcinoma and squamous-cell carcinoma. High expression of the COPD-associated CXCL14-correlating cluster of genes was linked in lung adenocarcinoma with poor survival. These data suggest that the smoking-induced expression of CXCL14 in the airway epithelium represents a novel potential molecular link between smoking-associated airway epithelial injury, COPD, and lung cancer.

  16. Epithelium-intrinsic NAIP/NLRC4 inflammasome drives infected enterocyte expulsion to restrict Salmonella replication in the intestinal mucosa.

    PubMed

    Sellin, Mikael E; Müller, Anna A; Felmy, Boas; Dolowschiak, Tamas; Diard, Médéric; Tardivel, Aubry; Maslowski, Kendle M; Hardt, Wolf-Dietrich

    2014-08-13

    The gut mucosal epithelium separates the host from the microbiota, but enteropathogens such as Salmonella Typhimurium (S.Tm) can invade and breach this barrier. Defenses against such acute insults remain incompletely understood. Using a murine model of Salmonella enterocolitis, we analyzed mechanisms limiting pathogen loads in the epithelium during early infection. Although the epithelium-invading S.Tm replicate initially, this intraepithelial replicative niche is restricted by expulsion of infected enterocytes into the lumen. This mechanism is compromised if inflammasome components (NAIP1-6, NLRC4, caspase-1/-11) are deleted, or ablated specifically in the epithelium, resulting in ∼100-fold higher intraepithelial loads and accelerated lymph node colonization. Interestingly, the cytokines downstream of inflammasome activation, interleukin (IL)-1α/β and IL-18, appear dispensable for epithelial restriction of early infection. These data establish the role of an epithelium-intrinsic inflammasome, which drives expulsion of infected cells to restrict the pathogen's intraepithelial proliferation. This may represent a general defense mechanism against mucosal infections. PMID:25121751

  17. Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758) (Gastropoda, Haliotidae)

    PubMed Central

    Bravo Portela, I.; Martinez-Zorzano, V. S.; Molist- Perez, I.; Molist García, P.

    2012-01-01

    The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium. PMID:22645482

  18. Activation of the IL-6/JAK/STAT3 signaling pathway in human middle ear cholesteatoma epithelium

    PubMed Central

    Liu, Wei; Xie, Shumin; Chen, Xing; Rao, Xingwang; Ren, Hongmiao; Hu, Bing; Yin, Tuanfang; Xiang, Yuyan; Ren, Jihao

    2014-01-01

    Interleukin-6 (IL-6) is one of the most important cytokines which has been shown to play a critical role in the pathogenesis of cholesteatoma. In this study, we aimed to investigate the expression of interleukin-6 (IL-6) and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in middle ear cholesteatoma epithelium in an effort to determine the role of IL-6/JAK/STAT3 signaling pathway in the pathogenesis of cholesteatoma. Immunohistochemistry was used to examine the expression of IL-6 and p-STAT3 in 25 human middle ear cholesteatoma samples and 15 normal external auditory canal (EAC) epithelium specimens. We also analyzed the relation of IL-6 and p-STAT3 expression levels to the degree of bone destruction in cholesteatoma. We found that the expression of IL-6 and p-STAT3 were significantly higher in cholesteatoma epithelium than in normal EAC epithelium (p<0.05). In cholesteatoma epithelium, a significant positive association was observed between IL-6 and p-STAT3 expression (p<0.05). However, no significant relationships were observed between the degree of bone destruction and the levels of IL-6 and p-STAT3 expression (p>0.05). To conclude, our results support the concept that IL-6/JAK/STAT3 signaling pathway is active and may play an important role in the mechanisms of epithelial hyper-proliferation responsible for cholesteatoma. PMID:24551293

  19. Neuronal chloride accumulation in olfactory epithelium of mice lacking NKCC1

    PubMed Central

    Nickell, William T.; Kleene, Nancy K.; Gesteland, Robert C.; Kleene, Steven J.

    2005-01-01

    When stimulated with odorants, olfactory receptor neurons (ORNs) produce a depolarizing receptor current. In isolated ORNs, much of this current is due to an efflux of Cl−. This implies that the neurons have one or more mechanisms for accumulating cytoplasmic Cl− at rest. Whether odors activate an efflux of Cl− in intact olfactory epithelium, where the ionic environment is poorly characterized, has not been previously determined. In mouse olfactory epithelium, we find that >80% of the summated electrical response to odors is blocked by niflumic acid or flufenamic acid, each of which inhibits Ca2+-activated Cl− channels in ORNs. This indicates that ORNs accumulate Cl− in situ. Recent evidence has shown that NKCC1, a Na+-K+-2Cl− cotransporter, contributes to Cl− accumulation in mammalian ORNs. However, we find that the epithelial response to odors is only reduced by 39% in mice carrying a null mutation in Nkcc1. As in the wild type, most of the response is blocked by niflumic acid or flufenamic acid, indicating that the underlying current is carried by Cl−. We conclude that ORNs effectively accumulate Cl− in situ even in the absence of NKCC1. The Cl−-transport mechanism underlying this accumulation has not yet been identified. PMID:16319203

  20. Neuronal chloride accumulation in olfactory epithelium of mice lacking NKCC1.

    PubMed

    Nickell, William T; Kleene, Nancy K; Gesteland, Robert C; Kleene, Steven J

    2006-03-01

    When stimulated with odorants, olfactory receptor neurons (ORNs) produce a depolarizing receptor current. In isolated ORNs, much of this current is caused by an efflux of Cl-. This implies that the neurons have one or more mechanisms for accumulating cytoplasmic Cl- at rest. Whether odors activate an efflux of Cl- in intact olfactory epithelium, where the ionic environment is poorly characterized, has not been previously determined. In mouse olfactory epithelium, we found that >80% of the summated electrical response to odors is blocked by niflumic acid or flufenamic acid, each of which inhibits Ca2+-activated Cl- channels in ORNs. This indicates that ORNs accumulate Cl- in situ. Recent evidence has shown that NKCC1, a Na+-K+-2Cl- cotransporter, contributes to Cl- accumulation in mammalian ORNs. However, we find that the epithelial response to odors is only reduced by 39% in mice carrying a null mutation in Nkcc1. As in the wild-type, most of the response is blocked by niflumic acid or flufenamic acid, indicating that the underlying current is carried by Cl-. We conclude that ORNs effectively accumulate Cl- in situ even in the absence of NKCC1. The Cl- -transport mechanism underlying this accumulation has not yet been identified.

  1. Topical drug delivery to retinal pigment epithelium with microfluidizer produced small liposomes.

    PubMed

    Lajunen, T; Hisazumi, K; Kanazawa, T; Okada, H; Seta, Y; Yliperttula, M; Urtti, A; Takashima, Y

    2014-10-01

    Drug delivery from topically instilled eye drops to the posterior segment of the eye has long been one of the greatest challenges of ocular drug development. We developed methods of liposome preparation utilizing a microfluidizer to achieve adjustable nanoparticle size (even less than 80 nm) and high loading capacity of plasmid DNA. The microfluidizing process parameters were shown to affect the size of the liposomes. Higher operating pressures and passage for at least 10 times through the microfluidizer produced small liposomes with narrow size distribution. The liposomes were physically stable for several months at +4°C. In vivo distribution of the optimized liposome formulations in the rat eyes was investigated with confocal microscopy of the histological specimens. Transferrin was used as a targeting ligand directed to retinal pigment epithelium. Size dependent distribution of liposomes to different posterior segment tissues was seen. Liposomes with the diameter less than 80 nm permeated to the retinal pigment epithelium whereas liposomes with the diameter of 100 nm or more were distributed to the choroidal endothelium. Active targeting was shown to be necessary for liposome retention to the target tissue. In conclusion, these microfluidizer produced small liposomes in eye drops are an attractive option for drug delivery to the posterior segment tissues of the eye. PMID:24810393

  2. Retinal pigment epithelium development, plasticity, and tissue homeostasis (Invited review for Experimental Eye Research)

    PubMed Central

    Fuhrmann, Sabine; Zou, ChangJiang; Levine, Edward M.

    2014-01-01

    The retinal pigment epithelium (RPE) is a simple epithelium interposed between the neural retina and the choroid. Although only 1 cell-layer in thickness, the RPE is a virtual workhorse, acting in several capacities that are essential for visual function and preserving the structural and physiological integrities of neighboring tissues. Defects in RPE function, whether through chronic dysfunction or age-related decline, are associated with retinal degenerative diseases including age-related macular degeneration. As such, investigations are focused on developing techniques to replace RPE through stem cell-based methods, motivated primarily because of the seemingly limited regeneration or self-repair properties of mature RPE. Despite this, RPE cells have an unusual capacity to transdifferentiate into various cell types, with the particular fate choices being highly context-dependent. In this review, we describe recent findings elucidating the mechanisms and steps of RPE development and propose a developmental framework for understanding the apparent contradiction in the capacity for low self-repair versus high transdifferentiation. PMID:24060344

  3. The retinal pigment epithelium as a gateway for monocyte trafficking into the eye.

    PubMed

    Benhar, Inbal; Reemst, Kitty; Kalchenko, Vyacheslav; Schwartz, Michal

    2016-06-01

    The choroid plexus epithelium within the brain ventricles orchestrates blood-derived monocyte entry to the central nervous system under injurious conditions, including when the primary injury site is remote from the brain. Here, we hypothesized that the retinal pigment epithelium (RPE) serves a parallel role, as a gateway for monocyte trafficking to the retina following direct or remote injury. We found elevated expression of genes encoding leukocyte trafficking determinants in mouse RPE as a consequence of retinal glutamate intoxication or optic nerve crush (ONC). Blocking VCAM-1 after ONC interfered with monocyte infiltration into the retina and resulted in a local pro-inflammatory cytokine bias. Live imaging of the injured eye showed monocyte accumulation first in the RPE, and subsequently in the retina, and peripheral leukocytes formed close contact with the RPE Our findings further implied that the ocular milieu can confer monocytes a phenotype advantageous for neuroprotection. These results suggest that the eye utilizes a mechanism of crosstalk with the immune system similar to that of the brain, whereby epithelial barriers serve as gateways for leukocyte entry. PMID:27107049

  4. Expression of Toll-like receptors in nasal epithelium in allergic rhinitis.

    PubMed

    Renkonen, Jutta; Toppila-Salmi, Sanna; Joenväärä, Sakari; Mattila, Pirkko; Parviainen, Ville; Hagström, Jaana; Haglund, Caj; Lehtonen, Mikko; Renkonen, Risto

    2015-08-01

    Toll-like receptors (TLRs) are important in barrier homeostasis, but their role in airborne allergies is not fully understood. The aim was to evaluate baseline and allergen-induced expression of TLR proteins in nasal epithelium during allergic rhinitis. Nineteen otherwise healthy non-smoking volunteers both allergic to birch pollen and non-allergic controls were enrolled. We took nasal biopsies before and after off-seasonal intranasal birch pollen or diluent challenge. The expression of epithelial TLR1-7, TLR9-10, and MyD88 proteins was immunohistochemically evaluated from the nasal biopsies. The TLR1-3 and TLR5-10 mRNAs were observed by RNA-microarray. Baseline epithelial expression of TLR proteins was wide and identical in controls and atopics. After off-seasonal intranasal birch pollen challenge, a negative change in the expression score of TLR1 and TLR6 proteins was detected in the atopic group. TLR mRNA expression was not affected by birch pollen challenge. Nasal epithelium seems to express all known TLRs. The mechanisms by which TLR1, and TLR6 proteins could affect pollen allergen transport need further studies.

  5. A mathematical model of the proton balance in the outer mantle epithelium of Anodonta cygnea L.

    PubMed

    Oliveira, P F; da Costa, A Rebelo; Ferreira, H G

    2008-05-01

    In the freshwater mollusc Anodonta cygnea and other unionids, the mantle plays an important role in the regulation of the movements of ions between the shell and the extrapaleal fluid. In this report, a mathematical model that attempts to describe the cell metabolic mechanisms underlying the operation of the outer mantle epithelium as a source of protons is presented. We encoded the information gathered by studying the epithelium in vitro, which includes the electrophysiology of the preparation, measurements of basic rates of transport of protons and base, the effect of metabolic and transport inhibitors on its electrical behavior and the dynamic measurements of pHi. The model was conceived so that the short-circuit current (Isc) and fluxes of Na+, K+ and Cl(-); intracellular volume; electrical potential; and ionic concentrations can be computed as a function of time. Furthermore, the analytical descriptions of all ionic fluxes involved are such that the effect of transport inhibitors can be simulated. In all the simulations performed, it was possible to reproduce the experimental results obtained with specific inhibitors of transport systems on the Isc and on pHi. In some cases, it was necessary to make alterations to one or more parameters of the reference condition. For each simulation carried out, the analysis of the results was consistent. The model is an analytical tool that can be used to show the internal coherence of the qualitative model previously proposed and to plan further experiments. PMID:18587603

  6. Drug Delivery Nanoparticles: Toxicity Comparison in Retinal Pigment Epithelium and Retinal Vascular Endothelial Cells.

    PubMed

    Lin, Haijiang; Yue, Yueran; Maidana, Daniel E; Bouzika, Peggy; Atik, Alp; Matsumoto, Hidetaka; Miller, Joan W; Vavvas, Demetrios G

    2016-01-01

    Multiple synthetic polymer nanoparticles (NPs) have been widely used as drug delivery systems. However, their toxicity to the retinal pigment epithelium and retinal endothelium remains unclear. In this study, we analyze the cytotoxic effects of three different kinds of NPs, made of poly lactic-co-glycolic acid (PLGA), polycaprolactone (PCL), and PEGylated PLGA (PEG-PLGA), in a retinal pigment epithelium cell line (ARPE-19) and in primary human retinal vascular endothelial cells (RVEC). PEG-PLGA NPs presented the lowest cytotoxicity on ARPE-19 cells and RVEC as assessed by MTT viability assay. While PLGA and PCL exhibited variable amounts of toxicity, no significant toxicity was observed when incubating cells with high PEG-PLGA concentrations (100 µg/ml), for up to 6 days. On both transmission electron microscopy and confocal microscopy, Rhodamine 6G-loaded PEG-PLGA NPs were observed intracellularly in multiple subcellular organelles. PEG-PLGA NPs are a potentially viable option for the treatment of eye diseases.

  7. Ciliated cells in vitamin A-deprived cultured hamster tracheal epithelium do divide

    SciTech Connect

    Rutten, A.A.; Beems, R.B.; Wilmer, J.W.; Feron, V.J.

    1988-09-01

    The pseudostratified tracheal epithelium, composed of a heterogeneous phenotypically varying cell population, was studied with respect to the in vitro cell proliferative activity of differentiated epithelial cells. Ciliated tracheal epithelial cells so far have been considered to be terminally differentiated, nonproliferating cells. Tracheal organ cultures obtained from vitamin A-deprived Syrian Golden hamsters were cultured in a vitamin A-deficient, serum-free, hormone-supplemented medium. In vitamin A-deprived tracheal epithelium treated with physiologically active all-trans retinol and low cigarette-smoke condensate concentrations it is possible to stimulate the cell proliferation of both basal and columnar cells. Therefore, the probability of finding proliferating columnar cells was increased compared with the in vivo and the vitamin A-deprived situation in which cell proliferative activity is relatively low. In the presence of cigarette-smoke condensate in a noncytotoxic concentration, basal, small mucous granule, ciliated, and indifferent tracheal epithelial cells incorporated (methyl-3H)-thymidine into the DNA during the S phase. The finding that ciliated cells were labeled was supported by serial sections showing the same labeled ciliated cell in two section planes separated by 2 to 3 micron, without labeled epithelial cells next to the ciliated cell. Furthermore, a ciliated tracheal epithelial cell incorporating (methyl-/sup 3/H)thymidine into DNA was also seen in tracheal cultures of vitamin A-deprived hamsters treated with all-trans retinol in a physiologic concentration.

  8. Distribution and ultrastructural characteristics of dark cells in squamous metaplasias of the respiratory tract epithelium. [Rats

    SciTech Connect

    Klein-Szanto, A.J.P.; Nettesheim, P.; Pine, A.; Martin, D.

    1981-05-01

    Dark epithelial basal cells were found in both carcinogen-induced and non-carcinogen-induced squamous metaplasias of the tracheal epithelium. Formaldehyde-induced squamous metaplasias exhibited 4% dark cells in the basal layer. Metaplasias induced by vitamin A deficiency and those induced by dimethylbenz(a)anthracene (DMBA) without atypia showed 18-20% basal dark cells. DMBA-induced metaplasias with moderate to severe atypia exhibited 50% basal dark cells. The labeling index of basal cells in metaplastic epithelia, regardless of the inducing agent, was 16-18%, ie, the same as that of the normal esophageal stratified squamous epithelium. The percentage of labeled dark basal cells per total dark cell population was approximately 19% in the non-carcinogen-induced metaplasias and in the DMBA-induced metaplasias without atypia. In the atypical metaplasias induced by DMA this percentage increased to 26. On the basis of ultrastructural observations, five types of dark epithelial cells could be distinguished in the metaplastic epithelia. Each type of squamous metaplasia could thus be recognized by a determined numerical distribution of dark cells in the basal layer and a specific pattern of distribution of the ultrastructurally defined dark cell categories.

  9. A Rotating Bioreactor for Scalable Culture and Differentiation of Respiratory Epithelium

    PubMed Central

    Raredon, Micha Sam Brickman; Ghaedi, Mahboobe; Calle, Elizabeth A.; Niklason, Laura E.

    2015-01-01

    Respiratory epithelium is difficult to grow in vitro, as it requires a well-maintained polarizing air–liquid interface (ALI) to maintain differentiation. Traditional methods rely on permeable membrane culture inserts, which are difficult to work with and are ill-suited for the production of large numbers of cells, such as the quantities required for cell-based clinical therapies. Herein, we investigate an alternative form of culture in which the cells are placed on a porous substrate that is continuously rolled, such that the monolayer of cells is alternately submerged in media or apically exposed to air. Our prototype bioreactor is reliable for up to 21 days of continuous culture and is designed for scale-up for large-scale cell culture with continuous medium and gas exchange. Normal human bronchial epithelial (NHBE) cells were cultured on an absorbent substrate in the reactor for periods of 7, 14, and 21 days and were compared to static controls that were submerged in media. Quantification by immunohistochemistry and quantitative PCR of markers specific to differentiated respiratory epithelium indicated increased cilia, mucous production, and tight junction formation in the rolled cultures, compared to static. Together with scanning electron microscopy and paraffin histology, the data indicate that the intermittent ALI provided by the rolling bioreactor promotes a polarized epithelial phenotype over a period of 21 days. PMID:26858899

  10. Effect of azelastine on sulphur dioxide induced impairment of ciliary motility in airway epithelium.

    PubMed Central

    Tamaoki, J; Chiyotani, A; Sakai, N; Takeyama, K; Konno, K

    1993-01-01

    OBJECTIVE--The effect of azelastine on airway mucociliary transport function was studied by measuring ciliary motility of human bronchial epithelium in vitro with a photoelectric method. METHOD--Bronchial epithelial cells were obtained by fibreoptic bronchoscopy, mounted in a Rose chamber, and perfused with Krebs-Henseleit solution. The preparations were placed on a microscope stage equipped with an illuminator, and the variations of light intensity caused by ciliary beating were detected by a photometer. RESULTS--The addition of azelastine to the perfusate increased ciliary beat frequency (CBF) in a dose dependent manner without ciliary discoordination. The mean (SE) maximal increase from the baseline value and the concentration required to produce a half maximal effect were 27.0 (4.2)% and 9.2 x 10(-6) mol/l, respectively. Exposure of the cells to the perfusate containing 3 ppm sulphur dioxide rapidly decreased CBF by 59.2 (5.0)%, and was accompanied by a reduction in intracellular cyclic AMP levels from 38.1 (4.3) to 10.1 (2.4) pmol/mg protein. This effect was prevented by pretreatment of cells with azelastine in a dose dependent manner. CONCLUSIONS--Azelastine not only stimulates ciliary motility of airway epithelium and hence mucociliary transport function, but may also protect against sulphur dioxide induced ciliary dysfunction, probably by inhibiting intracellular cyclic AMP loss. PMID:8322244

  11. Automated segmentation of serous pigment epithelium detachment in SD-OCT images

    NASA Astrophysics Data System (ADS)

    Sun, Zhuli; Shi, Fei; Xiang, Dehui; Chen, Haoyu; Chen, Xinjian

    2015-03-01

    Pigment epithelium detachment (PED) is an important clinical manifestation of multiple chorio-retinal disease processes, which can cause the loss of central vision. A 3-D method is proposed to automatically segment serous PED in SD-OCT images. The proposed method consists of five steps: first, a curvature anisotropic diffusion filter is applied to remove speckle noise. Second, the graph search method is applied for abnormal retinal layer segmentation associated with retinal pigment epithelium (RPE) deformation. During this process, Bruch's membrane, which doesn't show in the SD-OCT images, is estimated with the convex hull algorithm. Third, the foreground and background seeds are automatically obtained from retinal layer segmentation result. Fourth, the serous PED is segmented based on the graph cut method. Finally, a post-processing step is applied to remove false positive regions based on mathematical morphology. The proposed method was tested on 20 SD-OCT volumes from 20 patients diagnosed with serous PED. The average true positive volume fraction (TPVF), false positive volume fraction (FPVF), dice similarity coefficient (DSC) and positive predictive value (PPV) are 97.19%, 0.03%, 96.34% and 95.59%, respectively. Linear regression analysis shows a strong correlation (r = 0.975) comparing the segmented PED volumes with the ground truth labeled by an ophthalmology expert. The proposed method can provide clinicians with accurate quantitative information, including shape, size and position of the PED regions, which can assist diagnose and treatment.

  12. Serum clara cell protein: a sensitive biomarker of increased lung epithelium permeability caused by ambient ozone.

    PubMed

    Broeckaert, F; Arsalane, K; Hermans, C; Bergamaschi, E; Brustolin, A; Mutti, A; Bernard, A

    2000-06-01

    Ozone in ambient air may cause various effects on human health, including decreased lung function, asthma exacerbation, and even premature mortality. These effects have been evidenced using various clinical indicators that, although sensitive, do not specifically evaluate the O(3)-increased lung epithelium permeability. In the present study, we assessed the acute effects of ambient O(3) on the pulmonary epithelium by a new approach relying on the assay in serum of the lung-specific Clara cell protein (CC16 or CC10). We applied this test to cyclists who exercised for 2 hr during episodes of photochemical smog and found that O(3) induces an early leakage of lung Clara cell protein. The protein levels increased significantly into the serum from exposure levels as low as 0.060-0.084 ppm. Our findings, confirmed in mice exposed to the current U.S. National Ambient Air Quality Standards for O(3) (0.08 ppm for 8 hr) indicate that above the present natural background levels, there is almost no safety margin for the effects of ambient O(3) on airway permeability. The assay of CC16 in the serum represents a new sensitive noninvasive test allowing the detection of early effects of ambient O(3) on the lung epithelial barrier. PMID:10856027

  13. Proliferative and transcriptional identity of distinct classes of neural precursors in the mammalian olfactory epithelium

    PubMed Central

    Tucker, Eric S.; Lehtinen, Maria K.; Maynard, Tom; Zirlinger, Mariela; Dulac, Catherine; Rawson, Nancy; Pevny, Larysa; LaMantia, Anthony-Samuel

    2010-01-01

    Neural precursors in the developing olfactory epithelium (OE) give rise to three major neuronal classes – olfactory receptor (ORNs), vomeronasal (VRNs) and gonadotropin releasing hormone (GnRH) neurons. Nevertheless, the molecular and proliferative identities of these precursors are largely unknown. We characterized two precursor classes in the olfactory epithelium (OE) shortly after it becomes a distinct tissue at midgestation in the mouse: slowly dividing self-renewing precursors that express Meis1/2 at high levels, and rapidly dividing neurogenic precursors that express high levels of Sox2 and Ascl1. Precursors expressing high levels of Meis genes primarily reside in the lateral OE, whereas precursors expressing high levels of Sox2 and Ascl1 primarily reside in the medial OE. Fgf8 maintains these expression signatures and proliferative identities. Using electroporation in the wild-type embryonic OE in vitro as well as Fgf8, Sox2 and Ascl1 mutant mice in vivo, we found that Sox2 dose and Meis1 – independent of Pbx co-factors – regulate Ascl1 expression and the transition from lateral to medial precursor state. Thus, we have identified proliferative characteristics and a dose-dependent transcriptional network that define distinct OE precursors: medial precursors that are most probably transit amplifying neurogenic progenitors for ORNs, VRNs and GnRH neurons, and lateral precursors that include multi-potent self-renewing OE neural stem cells. PMID:20573694

  14. The cell biology of the intestinal epithelium and its relation to inflammatory bowel disease.

    PubMed

    Deuring, J Jasper; de Haar, Colin; Kuipers, Ernst J; Peppelenbosch, Maikel P; van der Woude, C Janneke

    2013-04-01

    The epithelial layer of our intestines must meet two opposing requirements. On one hand it must allow for efficient uptake of nutrients and fluids, on the other hand it is a vital defence barrier between the milieu interior and the milieu exterior. In contrast to the lung that by virtue of cilia movement is kept virtually sterile, the gut epithelium is confronted by a stupendous microbiological load and a substantial xenobiotic challenge. The efficiency by which our intestinal epithelium manages to deal with the challenge of efficient nutrient absorption while simultaneously fulfilling its barrier function is testimony to what the forces of evolution can accomplish. Importantly, our understanding as to how our gut epithelial compartment manages this balancing act is now rapidly emerging, answering one of the oldest questions in cell biology. Importantly, when aberrations in this balance occur, for instance as a consequence genetic polymorphisms, increased propensity to develop chronic inflammation and inflammatory bowel disease is the result. Thus the knowledge on intestinal cell biology and biochemistry is not only of academic interest but may also aid design of novel avenues for the rational treatment of mucosal disease.

  15. Serum clara cell protein: a sensitive biomarker of increased lung epithelium permeability caused by ambient ozone.

    PubMed Central

    Broeckaert, F; Arsalane, K; Hermans, C; Bergamaschi, E; Brustolin, A; Mutti, A; Bernard, A

    2000-01-01

    Ozone in ambient air may cause various effects on human health, including decreased lung function, asthma exacerbation, and even premature mortality. These effects have been evidenced using various clinical indicators that, although sensitive, do not specifically evaluate the O(3)-increased lung epithelium permeability. In the present study, we assessed the acute effects of ambient O(3) on the pulmonary epithelium by a new approach relying on the assay in serum of the lung-specific Clara cell protein (CC16 or CC10). We applied this test to cyclists who exercised for 2 hr during episodes of photochemical smog and found that O(3) induces an early leakage of lung Clara cell protein. The protein levels increased significantly into the serum from exposure levels as low as 0.060-0.084 ppm. Our findings, confirmed in mice exposed to the current U.S. National Ambient Air Quality Standards for O(3) (0.08 ppm for 8 hr) indicate that above the present natural background levels, there is almost no safety margin for the effects of ambient O(3) on airway permeability. The assay of CC16 in the serum represents a new sensitive noninvasive test allowing the detection of early effects of ambient O(3) on the lung epithelial barrier. Images Figure 1 Figure 2 Figure 3 PMID:10856027

  16. The chronicles of Porphyromonas gingivalis: the microbium, the human oral epithelium and their interplay

    PubMed Central

    Yilmaz, Özlem

    2009-01-01

    The microbiota of the human oral mucosa consists of a myriad of bacterial species that normally exist in commensal harmony with the host. Porphyromonas gingivalis, an aetiological agent in severe forms of periodontitis (a chronic inflammatory disease), is a prominent component of the oral microbiome and a successful colonizer of the oral epithelium. This Gram-negative anaerobe can also exist within the host epithelium without the existence of overt disease. Gingival epithelial cells, the outer lining of the gingival mucosa, which function as an important part of the innate immune system, are among the first host cells colonized by P. gingivalis. This review describes recent studies implicating the co-existence and intracellular adaptation of the organism in these target host cells. Specifically, recent findings on the putative mechanisms of persistence, intercellular dissemination and opportunism are highlighted. These new findings may also represent an original and valuable model for mechanistic characterization of other successful host-adapted, self-limiting, persistent intracellular bacteria in human epithelial tissues. PMID:18832296

  17. Drug Delivery Nanoparticles: Toxicity Comparison in Retinal Pigment Epithelium and Retinal Vascular Endothelial Cells.

    PubMed

    Lin, Haijiang; Yue, Yueran; Maidana, Daniel E; Bouzika, Peggy; Atik, Alp; Matsumoto, Hidetaka; Miller, Joan W; Vavvas, Demetrios G

    2016-01-01

    Multiple synthetic polymer nanoparticles (NPs) have been widely used as drug delivery systems. However, their toxicity to the retinal pigment epithelium and retinal endothelium remains unclear. In this study, we analyze the cytotoxic effects of three different kinds of NPs, made of poly lactic-co-glycolic acid (PLGA), polycaprolactone (PCL), and PEGylated PLGA (PEG-PLGA), in a retinal pigment epithelium cell line (ARPE-19) and in primary human retinal vascular endothelial cells (RVEC). PEG-PLGA NPs presented the lowest cytotoxicity on ARPE-19 cells and RVEC as assessed by MTT viability assay. While PLGA and PCL exhibited variable amounts of toxicity, no significant toxicity was observed when incubating cells with high PEG-PLGA concentrations (100 µg/ml), for up to 6 days. On both transmission electron microscopy and confocal microscopy, Rhodamine 6G-loaded PEG-PLGA NPs were observed intracellularly in multiple subcellular organelles. PEG-PLGA NPs are a potentially viable option for the treatment of eye diseases. PMID:26959123

  18. Measurement of the volume flow and hydraulic conductivity across the isolated dog retinal pigment epithelium.

    PubMed

    Tsuboi, S

    1987-11-01

    The isolated dog retinal pigment epithelium (RPE)-choroid was gently stretched on the inner surface of a spherical stainless mesh, retinal side upward, and clamped between half-chambers made of Kel-F. The volume flow across the tissue was monitored by the movement of water in capillary tubes connected to both chambers. With zero pressure difference across the RPE-choroid, retina-to-choroid fluid flow was determined to be 6.4 microliters/hr/cm2 (absorption). Removal of HCO-3 from the solution did not affect the fluid flow. However, the flow was reduced 88% in Cl- -free medium, indicating a coupling between water and Cl- absorption. The flow was also inhibited by ouabain (10(-5) M) and furosemide (10(-4) M). Hydraulic conductivity (Lp) of the RPE-choroid was determined to be 0.0126 microliters/min/cm2/mm Hg which places the dog RPE-choroid in the category of a "leaky" epithelium.

  19. FOXJ1 Prevents Cilia Growth Inhibition by Cigarette Smoke in Human Airway Epithelium In Vitro

    PubMed Central

    Brekman, Angelika; Walters, Matthew S.; Tilley, Ann E.

    2014-01-01

    Airway epithelium ciliated cells play a central role in clearing the lung of inhaled pathogens and xenobiotics, and cilia length and coordinated beating are important for airway clearance. Based on in vivo studies showing that the airway epithelium of healthy smokers has shorter cilia than that of healthy nonsmokers, we investigated the mechanisms involved in cigarette smoke–mediated inhibition of ciliogenesis by assessing normal human airway basal cell differentiation in air–liquid interface (ALI) cultures in the presence of nontoxic concentrations of cigarette smoke extract (CSE). Measurements of cilia length from Day 28 ALI cultures demonstrated that CSE exposure was associated with shorter cilia (P < 0.05), reproducing the effect of cigarette smoking on cilia length observed in vivo. This phenotype correlated with a broad CSE-mediated suppression of genes involved in cilia-related transcriptional regulation, intraflagellar transport, cilia motility, structural integrity, and basal body development but not of control genes or epithelial barrier integrity. The CSE-mediated inhibition of cilia growth could be prevented by lentivirus-mediated overexpression of FOXJ1, the major cilia-related transcription factor, which led to partial reversal of expression of cilia-related genes suppressed by CSE. Together, the data suggest that components of cigarette smoke are responsible for a broad suppression of genes involved in cilia growth, but, by stimulating ciliogenesis with the transcription factor FOXJ1, it may be possible to maintain close to normal cilia length despite the stress of cigarette smoking. PMID:24828273

  20. Morphological, histochemical and immunohistochemical study of the gill epithelium in the abyssal teleost fish Coelorhynchus coelorhynchus.

    PubMed

    Calabrò, Concetta; Albanese, Maria Pia; Lauriano, Eugenia Rita; Martella, Silvestro; Licata, Aurelio

    2005-01-01

    Histochemical and immunohistochemical study was carried out on nitrinergic innervation and neuroendocrine system in the gill epithelium of the abyssal fish Coelorhynchus coelorhynchus. The results showed that nNOS-positive nerve fibers, originating from the branchial arch were present in the subepithelial tissue of branchial primary filament. nNOS-positive neuroendocrine cells were also present in the primary filaments and secondary lamellae. Numerous mucous cells in the gill epithelium were AB/PAS-positive, while sialic acid was absent as confirmed by neuraminidase reaction and WGA lectin histochemistry. The mucus compounds in abyssal teleost fish are different from those found in pelagic species, being related to their living conditions. In abyssal species, greater numbers of chloride and neuroendocrine cells are involved in the movement of water and electrolytes. Neuroendocrine cells possess oxygen receptors which mediate the cardiovascular and ventilatory response to oxygen deficiency, as reported in teleost species. Besides, NO contributes through nervous stimulation to the regulation of vascular tone and blood circulation in the gill. PMID:15871563

  1. Decreased docosahexaenoic acid levels in retina and pigment epithelium of frogs fed crickets.

    PubMed

    Chen, H; Wiegand, R D; Anderson, R E

    1992-06-01

    Whole retina, rod outer segments, and retinal pigment epithelium of frogs (Rana pipiens) fed crickets for more than 1 year had significantly lower levels of docosahexaenoic acid (22: 6n-3) than the same tissues of frogs fed crickets for less than 1 month. Decreases in 22:6n-3 levels in these tissues were compensated for by increases in the n-6 polyunsaturated fatty acids (PUFAs), primarily 22:5n-6. There were no changes in the levels of saturated, monoenoic, or dienoic acids. Analysis of diacyl phospholipid molecular species (PLMS) revealed decreases in both the 22:6(n-3)-containing dipolyenoic molecular species in phosphatidylethanolamine and phosphatidylserine, and the monopolyenoic molecular species in phosphatidylcholine. These PLMS were replaced by species containing 22:5n-6 or other n-6 PUFAs. Examination of fatty acid methyl esters of total lipids extracted from crickets revealed that less than 1 mol% fatty acids were of the n-3 family, while more than 30 mol% were of the n-6 family. Thus, frogs raised on an n-3-deficient diet have reduced levels of n-3 PUFA in their retinas, rod outer segments, and retinal pigment epithelium. Although such changes have been reported for mammals, this is the first report of the effects of n-3 deficiency on the lipids of amphibians.

  2. Does autophagy in the midgut epithelium of centipedes depend on the day/night cycle?

    PubMed

    Rost-Roszkowska, M M; Chajec, Ł; Vilimova, J; Tajovský, K; Kszuk-Jendrysik, M

    2015-01-01

    The midgut epithelium of two centipedes, Lithobius forficatus and Scolopendra cingulata, is composed of digestive, secretory and regenerative cells. In L. forficatus, the autophagy occurred only in the cytoplasm of the digestive cells as a sporadic process, while in S. cingulata, it occurred intensively in the digestive, secretory and regenerative cells of the midgut epithelium. In both of the species that were analyzed, this process proceeded in a continuous manner and did not depend on the day/night cycle. Ultrastructural analysis showed that the autophagosomes and autolysosomes were located mainly in the apical and perinuclear cytoplasm of the digestive cells in L. forficatus. However, in S. cingulata, the entire cytoplasm was filled with autophagosomes and autolysosomes. Initially the membranes of phagophores surround organelles during autophagosome formation. Autolysosomes result from the fusion of autophagosomes and lysosomes. Residual bodies which are the last stage of autophagy were released into the midgut lumen due to necrosis. Autophagy in the midgut epithelia that were analyzed was confirmed using acid phosphatase and mono-dansyl-cadaverine stainings. PMID:25464151

  3. Development of human corneal epithelium on organized fibrillated transparent collagen matrices synthesized at high concentration.

    PubMed

    Tidu, Aurélien; Ghoubay-Benallaoua, Djida; Lynch, Barbara; Haye, Bernard; Illoul, Corinne; Allain, Jean-Marc; Borderie, Vincent M; Mosser, Gervaise

    2015-08-01

    Several diseases can lead to opacification of cornea requiring transplantation of donor tissue to restore vision. In this context, transparent collagen I fibrillated matrices have been synthesized at 15, 30, 60 and 90 mg/mL. The matrices were evaluated for fibril organizations, transparency, mechanical properties and ability to support corneal epithelial cell culture. The best results were obtained with 90 mg/mL scaffolds. At this concentration, the fibril organization presented some similarities to that found in corneal stroma. Matrices had a mean Young's modulus of 570 kPa and acellular scaffolds had a transparency of 87% in the 380-780 nm wavelength range. Human corneal epithelial cells successfully colonized the surface of the scaffolds and generated an epithelium with characteristics of corneal epithelial cells (i.e. expression of cytokeratin 3 and presence of desmosomes) and maintenance of stemness during culture (i.e. expression of ΔNp63α and formation of holoclones in colony formation assay). Presence of cultured epithelium on the matrices was associated with increased transparency (89%).

  4. Genetic factors influencing bystander signaling in murine bladder epithelium after low-dose irradiation in vivo.

    PubMed

    Mothersill, Carmel; Lyng, Fiona; Seymour, Colin; Maguire, Paula; Lorimore, Sally; Wright, Eric

    2005-04-01

    Radiation-induced bystander effects occur in cells that are not directly hit by radiation tracks but that receive signals from hit cells. They are well-documented in vitro consequences of low-dose exposure, but their relevance to in vivo radiobiology is not established. To investigate the in vivo production of bystander signals, bladder explants were established from two strains of mice known to differ significantly in both short-term and long-term radiation responses. These were investigated for the ability of 0.5 Gy total-body irradiation in vivo to induce production of bystander signals in bladder epithelium. The studies demonstrate that irradiated C57BL/6 mice, but not CBA/Ca mice, produce bystander signals that induce apoptosis and reduce clonogenic survival in reporter HPV-G-transfected keratinocytes. Transfer of medium from explants established from irradiated animals to explants established from unirradiated animals confirmed these differences in bladder epithelium. The responses to the in vivo-generated bystander signal exhibit genotypic differences in calcium signaling and also in signaling pathways indicative of a major role for the balance of pro-apoptosis and anti-apoptosis proteins in determining the overall response. The results clearly demonstrate the in vivo induction of bystander signals that are strongly influenced by genetic factors and have implications for radiation protection, medical imaging, and radiotherapy. PMID:15799694

  5. BMP signaling and cellular dynamics during regeneration of airway epithelium from basal progenitors

    PubMed Central

    Tadokoro, Tomomi; Gao, Xia; Hong, Charles C.; Hotten, Danielle; Hogan, Brigid L. M.

    2016-01-01

    The pseudostratified epithelium of the lung contains ciliated and secretory luminal cells and basal stem/progenitor cells. To identify signals controlling basal cell behavior we screened factors that alter their self-renewal and differentiation in a clonal organoid (tracheosphere) assay. This revealed that inhibitors of the canonical BMP signaling pathway promote proliferation but do not affect lineage choice, whereas exogenous Bmp4 inhibits proliferation and differentiation. We therefore followed changes in BMP pathway components in vivo in the mouse trachea during epithelial regeneration from basal cells after injury. The findings suggest that BMP signaling normally constrains proliferation at steady state and this brake is released transiently during repair by the upregulation of endogenous BMP antagonists. Early in repair, the packing of epithelial cells along the basal lamina increases, but density is later restored by active extrusion of apoptotic cells. Systemic administration of the BMP antagonist LDN-193189 during repair initially increases epithelial cell number but, following the shedding phase, normal density is restored. Taken together, these results reveal crucial roles for both BMP signaling and cell shedding in homeostasis of the respiratory epithelium. PMID:26811382

  6. BMP signaling and cellular dynamics during regeneration of airway epithelium from basal progenitors.

    PubMed

    Tadokoro, Tomomi; Gao, Xia; Hong, Charles C; Hotten, Danielle; Hogan, Brigid L M

    2016-03-01

    The pseudostratified epithelium of the lung contains ciliated and secretory luminal cells and basal stem/progenitor cells. To identify signals controlling basal cell behavior we screened factors that alter their self-renewal and differentiation in a clonal organoid (tracheosphere) assay. This revealed that inhibitors of the canonical BMP signaling pathway promote proliferation but do not affect lineage choice, whereas exogenous Bmp4 inhibits proliferation and differentiation. We therefore followed changes in BMP pathway components in vivo in the mouse trachea during epithelial regeneration from basal cells after injury. The findings suggest that BMP signaling normally constrains proliferation at steady state and this brake is released transiently during repair by the upregulation of endogenous BMP antagonists. Early in repair, the packing of epithelial cells along the basal lamina increases, but density is later restored by active extrusion of apoptotic cells. Systemic administration of the BMP antagonist LDN-193189 during repair initially increases epithelial cell number but, following the shedding phase, normal density is restored. Taken together, these results reveal crucial roles for both BMP signaling and cell shedding in homeostasis of the respiratory epithelium. PMID:26811382

  7. Atriopeptin II stimulates chloride secretion in the isolated operculum epithelium of Fundulus heteroclitus

    SciTech Connect

    Zadunaisky, J.A.; Scheide, J.I.

    1986-03-05

    Whole killifish efflux of /sup 36/Cl was increased more than 2x with the addition of 1.4 x 10/sup -7/ M atriopeptin (ANF) to the seawater bath. Atriopeptin II (10/sup -7/ M) added serosally to the isolated Fundulus heteroclitus opercular epithelium resulted in a consistent stimulation of the short-circuit current, from 129.5 +/- 12.3 to 153.5 +/- 13.4 ..mu..A/cm/sup 2/. Tissue resistance was decreased 10% from 114.9 +/- 14.2 to 103.9 +/- 11.8 Omega x cm/sup 2/ indicating a change in chloride conductance. The effect of ANF was maximal at 10/sup -7/M and mucosal addition of ANF was ineffective in stimulating the opercular current. The ANF current stimulation did not interfere with the isoproterenol (10/sup -6/ M) response but ANF did not stimulate the current if added after isoproterenol. Serosal addition of propranolol (10/sup -5/ M), sufficient to inhibit 10/sup -6/ M isoproterenol, had no effect on the ANF response. The serosal addition of 10/sup -6/ M tetrodotoxin or 10/sup -4/ M diltiazem did not inhibit the ANF response. The stimulatory effect observed by ANF did not involve the isoproterenol receptor or nerve activation; however, it was a distinct stimulatory response on the isolated opercular epithelium.

  8. Age and disease-related structural changes in the retinal pigment epithelium

    PubMed Central

    Bonilha, Vera L

    2008-01-01

    As the retinal pigment epithelium (RPE) ages, a number of structural changes occur, including loss of melanin granules, increase in the density of residual bodies, accumulation of lipofuscin, accumulation of basal deposits on or within Bruch’s membrane, formation of drusen (between the basal lamina of the RPE and the inner collagenous layer of Bruch’s membrane), thickening of Bruch’s membrane, microvilli atrophy and disorganization of the basal infoldings. Although these changes are well known, the basic mechanisms involved in them are frequently poorly understood. These age-related changes progress slowly and vary in severity in different individuals. These changes are also found in age-related macular degeneration (AMD), a late onset disease that severely impacts the RPE, but they are much more pronounced than during normal aging. However, the changes in AMD lead to severe loss of vision. Given the many supporting functions which the RPE serves for the retina, it is important to decipher the age-related changes in this epithelium in order to understand age-related changes in vision. PMID:19668732

  9. Analysis of damage to human ciliated nasopharyngeal epithelium by Neisseria meningitidis.

    PubMed Central

    Stephens, D S; Whitney, A M; Melly, M A; Hoffman, L H; Farley, M M; Frasch, C E

    1986-01-01

    We used an in vitro model of human nasopharyngeal tissue in organ culture to evaluate the effects of Neisseria meningitidis on human cilia and ciliary function. Encapsulated, viable meningococci damaged ciliated epithelium of nasopharyngeal organ cultures, whereas Neisseria subflava, a commensal species, did not. Meningococcus-induced ciliary damage was due to loss of ciliated cells to which meningococci were not attached. Damage was seen with piliated and nonpiliated meningococci and did not appear to require the presence of other specific meningococcal surface proteins. Meningococcal viability was a requirement for both ciliary damage and interactions of meningococci with microvilli of nonciliated epithelial cells. That is, filter-sterilized supernatants from meningococcus-infected organ cultures, heat-killed meningococci at high inoculum, and purified meningococcal or gonococcal lipopolysaccharide at concentrations of 100 micrograms/ml did not damage ciliary activity of nasopharyngeal organ cultures. In contrast, meningococcal lipopolysaccharide at 10 micrograms/ml markedly damaged ciliary activity of human fallopian tube organ cultures, suggesting a selective toxicity of lipopolysaccharide for specific human ciliated cells. Damage to nasopharyngeal ciliated epithelium by N. meningitidis may be an important first step in meningococcal colonization of the human nasopharynx, but meningococcal lipopolysaccharide does not appear to be directly responsible for this toxicity. Images PMID:2867973

  10. Induction of ectopic taste buds by SHH reveals the competency and plasticity of adult lingual epithelium.

    PubMed

    Castillo, David; Seidel, Kerstin; Salcedo, Ernesto; Ahn, Christina; de Sauvage, Frederic J; Klein, Ophir D; Barlow, Linda A

    2014-08-01

    Taste buds are assemblies of elongated epithelial cells, which are innervated by gustatory nerves that transmit taste information to the brain stem. Taste cells are continuously renewed throughout life via proliferation of epithelial progenitors, but the molecular regulation of this process remains unknown. During embryogenesis, sonic hedgehog (SHH) negatively regulates taste bud patterning, such that inhibition of SHH causes the formation of more and larger taste bud primordia, including in regions of the tongue normally devoid of taste buds. Here, using a Cre-lox system to drive constitutive expression of SHH, we identify the effects of SHH on the lingual epithelium of adult mice. We show that misexpression of SHH transforms lingual epithelial cell fate, such that daughter cells of lingual epithelial progenitors form cell type-replete, onion-shaped taste buds, rather than non-taste, pseudostratified epithelium. These SHH-induced ectopic taste buds are found in regions of the adult tongue previously thought incapable of generating taste organs. The ectopic buds are composed of all taste cell types, including support cells and detectors of sweet, bitter, umami, salt and sour, and recapitulate the molecular differentiation process of endogenous taste buds. In contrast to the well-established nerve dependence of endogenous taste buds, however, ectopic taste buds form independently of both gustatory and somatosensory innervation. As innervation is required for SHH expression by endogenous taste buds, our data suggest that SHH can replace the need for innervation to drive the entire program of taste bud differentiation. PMID:24993944

  11. Fate of marginal neuroblasts in the vomeronasal epithelium of adult mice.

    PubMed

    De La Rosa-Prieto, C; Saiz-Sanchez, D; Ubeda-Bañon, I; Argandoña-Palacios, L; Garcia-Muñozguren, S; Martinez-Marcos, A

    2009-12-10

    Chemical stimuli are sensed through the olfactory and vomeronasal epithelia, and the sensory cells of both systems undergo neuronal turnover during adulthood. In the vomeronasal epithelium, stem cells adjacent to the basal lamina divide and migrate to replace two classes of sensory neurons: apical neurons that express G(i2alpha)-linked V1R vomeronasal receptors and project to the anterior accessory olfactory bulb, and basal neurons that express G(oalpha)-linked V2R receptors and project to the posterior accessory olfactory bulb. Most of the dividing cells are present in the margins of the epithelium and only migrate locally. Previous studies have suggested that these marginal cells may participate in growth, sensory cell replacement or become apoptotic before maturation; however, the exact fate of these cells have remained unclear. In this work we investigated the fate of these marginal cells by analyzing markers of neurogenesis (bromodeoxyuridine incorporation), apoptosis (caspase-3), and neuronal maturation (olfactory marker protein and Neurotrace Nissl stain). Our data reveal a pool of dividing cells in the epithelial margins that predominantly give rise to mature neurons and only rarely undergo apoptosis. Newly generated cells are several times more numerous than apoptotic cells. These marginal neuroblasts could therefore constitute a net neural addition zone during adulthood.

  12. Induction of ectopic taste buds by SHH reveals the competency and plasticity of adult lingual epithelium.

    PubMed

    Castillo, David; Seidel, Kerstin; Salcedo, Ernesto; Ahn, Christina; de Sauvage, Frederic J; Klein, Ophir D; Barlow, Linda A

    2014-08-01

    Taste buds are assemblies of elongated epithelial cells, which are innervated by gustatory nerves that transmit taste information to the brain stem. Taste cells are continuously renewed throughout life via proliferation of epithelial progenitors, but the molecular regulation of this process remains unknown. During embryogenesis, sonic hedgehog (SHH) negatively regulates taste bud patterning, such that inhibition of SHH causes the formation of more and larger taste bud primordia, including in regions of the tongue normally devoid of taste buds. Here, using a Cre-lox system to drive constitutive expression of SHH, we identify the effects of SHH on the lingual epithelium of adult mice. We show that misexpression of SHH transforms lingual epithelial cell fate, such that daughter cells of lingual epithelial progenitors form cell type-replete, onion-shaped taste buds, rather than non-taste, pseudostratified epithelium. These SHH-induced ectopic taste buds are found in regions of the adult tongue previously thought incapable of generating taste organs. The ectopic buds are composed of all taste cell types, including support cells and detectors of sweet, bitter, umami, salt and sour, and recapitulate the molecular differentiation process of endogenous taste buds. In contrast to the well-established nerve dependence of endogenous taste buds, however, ectopic taste buds form independently of both gustatory and somatosensory innervation. As innervation is required for SHH expression by endogenous taste buds, our data suggest that SHH can replace the need for innervation to drive the entire program of taste bud differentiation.

  13. Extremely elongated Mitochondria in Ioncytes of the saccular Epithelium of a Teleost, Oreochromis mossambiscus (Cichlidae)

    NASA Astrophysics Data System (ADS)

    Muders, K.; Anken, R.; Ibsch, M.; Rahmann, H.

    Earlier investigations have clearly shown that altered gravity affects the calcium incorporation of fish inner ear otoliths. The incorporation of such inorganic components requires a particular composition of the endolymph, which is maintained by specialized cells in the inner ear epithelium, which are responsible for ion exchange. These so-called ionocytes therefore may play an important role in altered gravity affected ion deposition on otoliths. In order to clarify the ultrastructure of ionocytes, respective cells within the saccular epithelium of the cichlid fish Oreochromis mossamb cus were analyzed byi imaging of thick sections with energy -filtering transmission electron microscopy. It was found that ionocytes do not contain numerous mitochondria of litte size as has been suggested earlier but rather few, extremely elongated megamitochondria. Such worm-like mitochondria seemed hitherto to be restricted to some higher plants and fungi. Since the particular mitochondrial structure is important for normal cell function, such megamitochondria possibly reflect a functional advantage in the context of the presumed role of teleostean ionocytes in regulating the electrolyte composition of the endolymph. Acknowledgement: This work was financially supported by the German Aerospace Center (DLR) (FKZ: 50 WB 9997).

  14. Transition between columnar absorptive cells and goblet cells in the rat jejunal epithelium.

    PubMed

    Kurosumi, K; Shibuichi, I; Tosaka, H

    1981-11-01

    Electron microscopic observation of the jejunal epithelium of rats demonstrated morphological evidence of a transition between columnar absorptive cells and growing goblet cells. The columnar cells in both the villi and crypts have features suggestive of absorptive functions. They are provided with apical invaginations continuous to the intermicrovillous space. Absorbed lipid is observed in small vesicles in the terminal web layer, and chylomicrons derived here from are contained in large vacuoles near the Golgi apparatus. Ferritin particles artificially infused into the gut lumen were absorbed into the vacuoles in the subapical zone of columnar cells of suckling rats. Growing goblet cells situated in the crypt epithelium contain surface invaginations and lysosomes which are the same in structure as those found in absorptive cells nearby. Fat droplets evidently absorbed by the growing goblet cell were observed among immature mucus droplets. Artificially infused ferritin particles were found in vacuoles and lysosomes near the Golgi apparatus of some goblet cells of suckling rats. Some goblet cells on the intestinal villi of suckling rats looked immature and their microvilli and cytoplasmic matrix were clear like those of columnar absorptive cells. The transition between these goblet cells with clear cytoplasm and the mature goblet cells with dark cytoplasm was observed. These morphological evidences indicate that some of columnar cells already differentiated to absorptive cells are capable of transforming into mucus-producing (goblet) cells. It is suggested that not only undifferentiated columnar cells in the crypt base but also considerably differentiated columnar cells with absorptive function can differentiate into goblet cells.

  15. A mathematical model of the proton balance in the outer mantle epithelium of Anodonta cygnea L.

    PubMed

    Oliveira, P F; da Costa, A Rebelo; Ferreira, H G

    2008-05-01

    In the freshwater mollusc Anodonta cygnea and other unionids, the mantle plays an important role in the regulation of the movements of ions between the shell and the extrapaleal fluid. In this report, a mathematical model that attempts to describe the cell metabolic mechanisms underlying the operation of the outer mantle epithelium as a source of protons is presented. We encoded the information gathered by studying the epithelium in vitro, which includes the electrophysiology of the preparation, measurements of basic rates of transport of protons and base, the effect of metabolic and transport inhibitors on its electrical behavior and the dynamic measurements of pHi. The model was conceived so that the short-circuit current (Isc) and fluxes of Na+, K+ and Cl(-); intracellular volume; electrical potential; and ionic concentrations can be computed as a function of time. Furthermore, the analytical descriptions of all ionic fluxes involved are such that the effect of transport inhibitors can be simulated. In all the simulations performed, it was possible to reproduce the experimental results obtained with specific inhibitors of transport systems on the Isc and on pHi. In some cases, it was necessary to make alterations to one or more parameters of the reference condition. For each simulation carried out, the analysis of the results was consistent. The model is an analytical tool that can be used to show the internal coherence of the qualitative model previously proposed and to plan further experiments.

  16. Histological features of respiratory epithelium of calves held at differing temperature and humidity.

    PubMed Central

    Jericho, K W; Magwood, S E

    1977-01-01

    The effect of ambient temperature and humidity on the structure of respiratory epithelium of calves was studied. Four calves of each of three experiments were acclimatized to a nonoperational environmental chamber for six days and then exposed to constant extremes of temperatures and relative humidity of one of 30 degrees C --35%, or 27 degrees C--92%, or 5 degrees C--92% respectively in this chamber for eight days each. Five calves (3 and 2) were similarly acclimatized then exposed to 1 degrees C--40%. Nasal swabs were taken from all animals at regular intervals. Swabs of three animals yielded Mycoplasma spp. and one swab yielded the virus of infectious bovine rhinotracheitis. Detailed histological studies of respiratory epithelium of nose, trachea, major bronchus and terminal bronchioli were conducted at four sites. Goblet cells were least in calves held in hot and dry air; calves held in dry air had the least polymorphonuclear cells and the greatest prevalence of hypochromatic cell layers and vacuolation of epithelial cells. Differences between experiments were evident most for sites of trachea and major bronchus. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. Fig. 9. Fig. 1. Fig. 2. Fig. 3. PMID:922554

  17. Regulation of chloride secretion in dog tracheal epithelium by protein kinase C

    SciTech Connect

    Barthelson, R.A.; Jacoby, D.B.; Widdicombe, J.H. )

    1987-12-01

    The effects of stimulating protein kinase C on Cl{sup {minus}} secretion across dog tracheal epithelium were investigated. The phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA), and the synthetic diacylglycerol, 1-oleolyl-2-acetylglycerol (OAG), which stimulate protein kinase C (PKC), both stimulated short-circuit current (I{sub sc}) with K{sub d} of 10 nM and 1 {mu}M, respectively. In Cl{sup {minus}}-free solution, the increases in I{sub sc} were virtually abolished, suggesting that these compounds stimulate Cl{sup {minus}} secretion, a hypothesis confirmed for TPA by measurement of {sup 36}Cl{sup {minus}} fluxes. The stimulations of Cl{sup {minus}} secretion were not sensitive to indomethacin, nor were cAMP levels elevated during stimulation. In addition to its transient stimulatory effect, TPA at high doses caused the eventual lowering of the base-line I{sub sc} and a block of subsequent stimulation by cAMP-mediated agonists. This was probably not the result of toxicity or an effect on adenylate cyclase or on cAMP-dependent protein kinase. Cell extracts from both cultured and native dog tracheal epithelial cells showed strong PKC activities. These results suggest that PKC may play a role in regulating Cl{sup {minus}} secretion across dog tracheal epithelium.

  18. Trop2 marks transient gastric fetal epithelium and adult regenerating cells after epithelial damage

    PubMed Central

    Fernandez Vallone, Valeria; Leprovots, Morgane; Strollo, Sandra; Vasile, Gabriela; Lefort, Anne; Libert, Frederick; Vassart, Gilbert; Garcia, Marie-Isabelle

    2016-01-01

    ABSTRACT Mouse fetal intestinal progenitors lining the epithelium prior to villogenesis grow as spheroids when cultured ex vivo and express the transmembrane glycoprotein Trop2 as a marker. Here, we report the characterization of Trop2-expressing cells from fetal pre-glandular stomach, growing as immortal undifferentiated spheroids, and their relationship with gastric development and regeneration. Trop2+ cells generating gastric spheroids differed from adult glandular Lgr5+ stem cells, but appeared highly related to fetal intestinal spheroids. Although they shared a common spheroid signature, intestinal and gastric fetal spheroid-generating cells expressed organ-specific transcription factors and were committed to intestinal and glandular gastric differentiation, respectively. Trop2 expression was transient during glandular stomach development, being lost at the onset of gland formation, whereas it persisted in the squamous forestomach. Undetectable under homeostasis, Trop2 was strongly re-expressed in glands after acute Lgr5+ stem cell ablation or following indomethacin-induced injury. These highly proliferative reactive adult Trop2+ cells exhibited a transcriptome displaying similarity with that of gastric embryonic Trop2+ cells, suggesting that epithelium regeneration in adult stomach glands involves the partial re-expression of a fetal genetic program. PMID:26989172

  19. Do G protein-coupled receptors expressed in human lingual epithelium interact with HPV11?

    PubMed

    Durzyński, Lukasz; Gaudin, Jean-Charles; Breuils, Laure; Szydłowski, Jaroslaw; Goździcka-Józefiak, Anna; Haertlé, Thomas

    2007-10-01

    Human papillomaviruses infect epithelia but little is known about the nature of cell surface receptors interacting with the viral particles. It has been proposed that glycosaminoglycans and integrins may be involved in the attachment process. In the present study, the putative interactions of virus-like particles of human papillomavirus type 11 (HPV11), which present a tropism for nasopharyngeal epithelia, with olfactory and taste receptors expressed in the human lingual epithelium were studied. The L1 protein of HPV11 was produced in insect cells. The presence of L1 virus-like particles was analyzed by ELISA using monoclonal antibodies specific for full-size particles and by electron microscopy. Using immunofluorescence, it was observed that virus-like particles interacted with taste buds from murine tongue, with the tagged human olfactory receptor hJCG5 expressed in HEK-293 but not with the tagged taste receptor hT2R4. This therefore suggests that hJCG5 may be involved in the adsorption process of HPV11 to lingual epithelium serving as a so-called "adsorption-adhesive molecule." PMID:17705193

  20. Glandular Epithelium as a Possible Source of a Fertility Signal in Ectatomma tuberculatum (Hymenoptera: Formicidae) Queens

    PubMed Central

    da Hora, Riviane Rodigues; Delabie, Jacques Hubert Charles; dos Santos, Carolina Gonçalves; Serrão, José Eduardo

    2010-01-01

    The wax layer covering the insect's cuticle plays an important protective role, as for example, uncontrolled water loss. In social insects, wax production is well-known in some bees that use it for nest building. Curiously, mated-fertile queens of the ant Ectatomma tuberculatum produce an uncommon extra-wax coat and, consequently queens (mated-fertile females) are matte due to such extra cuticular hydrocarbon (CHC) coat that covers the cuticle and masks the brightness of the queens' cuticle while gynes (virgin-infertile queens) are shiny. In this study, histological analysis showed differences in the epidermis between fertile (i.e., queens or gynes with highly ovarian activity) and infertile females (gynes or workers with non developed ovaries). In fertile females the epidermis is a single layer of cubic cells found in all body segments whereas in infertile females it is a thin layer of flattened cells. Ultrastructural features showed active secretory tissue from fertile females similar to the glandular epithelium of wax-producing bees (type I gland). Different hypotheses related to the functions of the glandular epithelium exclusive to the E. tuberculatum fertile queens are discussed. PMID:20419093

  1. ELECTRON MICROSCOPY OF ABSORPTION OF TRACER MATERIALS BY TOAD URINARY BLADDER EPITHELIUM.

    PubMed

    CHOI, J K

    1965-05-01

    The absorption of Thorotrast and saccharated iron oxide by the epithelium of the toad urinary bladder was studied by electron microscopy. Whether the toads were hydrated, dehydrated, or given Pitressin, no significant differences in transport of colloidal particles by epithelial cells were observed. This implies that these physiological factors had little effect on the transport of the tracer particles. Tracer particles were encountered in three types of epithelial cells which line the bladder lumen, but most frequently in the mitochondria-rich cells. Tracer materials were incorporated into the cytoplasm of epithelial cells after being adsorbed to the coating layer covering the luminal surface of the cells. In the intermediate stage (1 to 3 hours after introducing tracer) particles were present in small vesicles, tubules, and multivesicular bodies. In the later stages (up to 65 hours), the particles were more commonly seen to be densely packed within large membrane-bounded bodies which were often found near the Golgi region. These large bodies probably were formed by the fusion of small vesicles. Irrespective of the stages of absorption, no particles were found in the intercellular spaces or in the submucosa. Particles apparently did not penetrate the intercellular spaces of the epithelium beyond the level of the tight junction.

  2. Biological and genetic properties of the p53 null preneoplastic mammary epithelium

    NASA Technical Reports Server (NTRS)

    Medina, Daniel; Kittrell, Frances S.; Shepard, Anne; Stephens, L. Clifton; Jiang, Cheng; Lu, Junxuan; Allred, D. Craig; McCarthy, Maureen; Ullrich, Robert L.

    2002-01-01

    The absence of the tumor suppressor gene p53 confers an increased tumorigenic risk for mammary epithelial cells. In this report, we describe the biological and genetic properties of the p53 null preneoplastic mouse mammary epithelium in a p53 wild-type environment. Mammary epithelium from p53 null mice was transplanted serially into the cleared mammary fat pads of p53 wild-type BALB/c female to develop stable outgrowth lines. The outgrowth lines were transplanted for 10 generations. The outgrowths were ductal in morphology and progressed through ductal hyperplasia and ductal carcinoma in situ before invasive cancer. The preneoplastic outgrowth lines were immortal and exhibited activated telomerase activity. They are estrogen and progesterone receptor-positive, and aneuploid, and had various levels of tumorigenic potential. The biological and genetic properties of these lines are distinct from those found in most hyperplastic alveolar outgrowth lines, the form of mammary preneoplasia occurring in most traditional models of murine mammary tumorigenesis. These results indicate that the preneoplastic cell populations found in this genetically engineered model are similar in biological properties to a subset of precurser lesions found in human breast cancer and provide a unique model to identify secondary events critical for tumorigenicity and invasiveness.

  3. Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium

    PubMed Central

    Pavlov, Tengis S.; Ilatovskaya, Daria V.; Palygin, Oleg; Levchenko, Vladislav; Pochynyuk, Oleh; Staruschenko, Alexander

    2015-01-01

    Cyst initiation and expansion during polycystic kidney disease is a complex process characterized by abnormalities in tubular cell proliferation, luminal fluid accumulation and extracellular matrix formation. Activity of ion channels and intracellular calcium signaling are key physiologic parameters which determine functions of tubular epithelium. We developed a method suitable for real-time observation of ion channels activity with patch-clamp technique and registration of intracellular Ca2+ level in epithelial monolayers freshly isolated from renal cysts. PCK rats, a genetic model of autosomal recessive polycystic kidney disease (ARPKD), were used here for ex vivo analysis of ion channels and calcium flux. Described here is a detailed step-by-step procedure designed to isolate cystic monolayers and non-dilated tubules from PCK or normal Sprague Dawley (SD) rats, and monitor single channel activity and intracellular Ca2+ dynamics. This method does not require enzymatic processing and allows analysis in a native setting of freshly isolated epithelial monolayer. Moreover, this technique is very sensitive to intracellular calcium changes and generates high resolution images for precise measurements. Finally, isolated cystic epithelium can be further used for staining with antibodies or dyes, preparation of primary cultures and purification for various biochemical assays. PMID:26381526

  4. Quantitative morphology of the testicular tubular epithelium in the water buffalo (Bubalus bubalis).

    PubMed

    Wrobel, K H; Pawar, H S

    1992-01-01

    Ultrastructural features and morphometric evaluations of water buffalo seminiferous epithelium are reported for the 6 phases of the spermatogenic cycle. The relative Sertoli cell volume varies between 30% (phase 4) and 39% (phase 8), the calculated volume of a Sertoli cell between 7118 microns3 and 8968 microns3 (phase 4). Smooth ER is the organelle that exhibits the most prominent changes in Sertoli cells during the spermatogenic cycle: it occupies about 6% in phase 3 and 21% in phase 4. All spermatogenic cells of the same clone present cytoplasmic bridges among them. From preleptotene (about 470 microns3) to late diplotene (about 2300 microns3) the volume of a primary spermatocyte increases nearly 5-fold; their nuclear volumes increase 3.5-fold in the same period. Secondary spermatocytes are found only in phase 4 of the cycle. Due to partial cell necrosis and autolysis late maturation phase spermatids display not more than 25% of the size of early cap phase spermatids. 63% of all numerically possible germ cells disappear from the seminiferous epithelium during spermatogenesis. Particularly heavy cell loss is observed in phase 4 and involves the spermatogonial fraction as well as cells during the second meiotic division.

  5. Respiratory syncytial virus alters electrophysiologic properties in cotton rat airway epithelium.

    PubMed

    Cloutier, M M; Wong, D; Ogra, P L

    1989-01-01

    The effect of respiratory syncytial virus (RSV) infection on the electrophysiologic properties of the airway epithelium was studied in tracheas obtained from cotton rats, after in vivo exposure to the virus. RSV infection was documented by tissue culture infectivity and immunofluorescent antibody techniques. Light microscopic studies of the tracheas 72 hours after exposure to RSV revealed normal epithelial morphology. RSV infection produced a 28% decrease in short-circuit current (Isc) and an almost 100% increase in tissue resistance. The decrease in Isc was partially attributed to a decrease in Cl secretion, while the increase in tissue resistance was associated with significant restriction to sodium and chloride movement through the paracellular pathway in RSV-infected tracheas. We conclude from these studies that RSV infection in the cotton rat trachea produces significant changes in active and passive ion flows. Alterations in ion transport across the airway epithelium may result in changes in secondary water transport across the airways and may contribute to the pathophysiology of RSV bronchiolitis and other locally invasive mucosal viral infections in children.

  6. Neuronal chloride accumulation in olfactory epithelium of mice lacking NKCC1.

    PubMed

    Nickell, William T; Kleene, Nancy K; Gesteland, Robert C; Kleene, Steven J

    2006-03-01

    When stimulated with odorants, olfactory receptor neurons (ORNs) produce a depolarizing receptor current. In isolated ORNs, much of this current is caused by an efflux of Cl-. This implies that the neurons have one or more mechanisms for accumulating cytoplasmic Cl- at rest. Whether odors activate an efflux of Cl- in intact olfactory epithelium, where the ionic environment is poorly characterized, has not been previously determined. In mouse olfactory epithelium, we found that >80% of the summated electrical response to odors is blocked by niflumic acid or flufenamic acid, each of which inhibits Ca2+-activated Cl- channels in ORNs. This indicates that ORNs accumulate Cl- in situ. Recent evidence has shown that NKCC1, a Na+-K+-2Cl- cotransporter, contributes to Cl- accumulation in mammalian ORNs. However, we find that the epithelial response to odors is only reduced by 39% in mice carrying a null mutation in Nkcc1. As in the wild-type, most of the response is blocked by niflumic acid or flufenamic acid, indicating that the underlying current is carried by Cl-. We conclude that ORNs effectively accumulate Cl- in situ even in the absence of NKCC1. The Cl- -transport mechanism underlying this accumulation has not yet been identified. PMID:16319203

  7. ALKBHs-facilitated RNA modifications and de-modifications.

    PubMed

    A Alemu, Endalkachew; He, Chuan; Klungland, Arne

    2016-08-01

    The AlkB gene that protects E.coli against methylation damage to DNA was identified more than 3 decades ago. 20 years later, the AlkB protein was shown to catalyze repair of methylated DNA base lesions by oxidative demethylation. Two human AlkB homologs were characterized with similar DNA repair activities and seven additional human AlkB homologs were identified based on sequence homology. All these dioxygenases, ALKBH1-8 and FTO, contain a conserved α-ketoglutarate/iron-dependent domain for methyl modifications and de-modifications. Well-designed research over the last 10 years has identified unforeseen substrate heterogeneity for the AlkB homologs, including novel reversible methyl modifications in RNA. The discoveries of RNA demethylation catalyzed by AlkB family enzymes initiated a new realm of gene expression regulation, although the understanding of precise endogenous activities and roles of these RNA demethylases are still undeveloped. It is worth mentioning that the AlkB mechanism and use of α-ketoglutarate have also emerged to be essential for many enzymes in epigenetic reprogramming that modify and de-modify methylated bases in DNA and methylated amino acids in histones. PMID:27237585

  8. Response of the macaque nasal epithelium to ambient levels of ozone. A morphologic and morphometric study of the transitional and respiratory epithelium

    SciTech Connect

    Harkema, J.R.; Plopper, C.G.; Hyde, D.M.; St. George, J.A.; Wilson, D.W.; Dungworth, D.L.

    1987-07-01

    Although ozone (O/sub 3/)-induced bronchiolitis has been morphologically characterized, effects of O/sub 3/ on the upper respiratory tract have not been thoroughly investigated. The purpose of this study was to determine whether exposures to ambient levels of O/sub 3/ induce lesions in the nasal mucosa. Bonnet monkeys were exposed to 0.00, 0.15, or 0.30 ppm O/sub 3/ for 6 or 90 days, 8 hours/day. After exposure, nasal mucosa was processed for light and electron microscopy. Quantitative changes were evident in the nasal transitional and respiratory epithelium. At 6 or 90 days of exposure to 0.15 or 0.30 ppm O/sub 3/ lesions consisted of ciliated cell necrosis, shortened cilia, and secretory cell hyperplasia. Inflammatory cell influx was only present at 6 days of exposure. Ultrastructural changes in goblet cells were evident at 90 days. Ambient levels of O/sub 3/ can induce significant nasal epithelial lesions, which may compromise upper respiratory defense mechanisms.

  9. The ‘de novo’ DNA methyltransferase Dnmt3b compensates the Dnmt1-deficient intestinal epithelium

    PubMed Central

    Elliott, Ellen N; Sheaffer, Karyn L; Kaestner, Klaus H

    2016-01-01

    Dnmt1 is critical for immediate postnatal intestinal development, but is not required for the survival of the adult intestinal epithelium, the only rapidly dividing somatic tissue for which this has been shown. Acute Dnmt1 deletion elicits dramatic hypomethylation and genomic instability. Recovery of DNA methylation state and intestinal health is dependent on the de novo methyltransferase Dnmt3b. Ablation of both Dnmt1 and Dnmt3b in the intestinal epithelium is lethal, while deletion of either Dnmt1 or Dnmt3b has no effect on survival. These results demonstrate that Dnmt1 and Dnmt3b cooperate to maintain DNA methylation and genomic integrity in the intestinal epithelium. DOI: http://dx.doi.org/10.7554/eLife.12975.001 PMID:26808831

  10. Medium Modification of Vector Mesons

    SciTech Connect

    Chaden Djalali, Michael Paolone, Dennis Weygand, Michael H. Wood, Rakhsha Nasseripour

    2011-03-01

    The theory of the strong interaction, Quantum Chromodynamics (QCD), has been remarkably successful in describing high-energy and short-distance-scale experiments involving quarks and gluons. However, applying QCD to low energy and large-distance scale experiments has been a major challenge. Various QCD-inspired models predict a partial restoration of chiral symmetry in nuclear matter with modifications of the properties of hadrons from their free-space values. Measurable changes such as a shift in mass and/or a change of width are predicted at normal nuclear density. Photoproduction of vector mesons off nuclei have been performed at different laboratories. The properties of the ρ, ω and φ mesons are investigated either directly by measuring their mass spectra or indirectly through transparency ratios. The latest results regarding medium modifications of the vector mesons in the nuclear medium will be discussed.

  11. Dynamic RNA modifications in disease.

    PubMed

    Klungland, Arne; Dahl, John Arne

    2014-06-01

    While the presence of 6-methyladenosine (m6A) modifications in mRNA was noted several decades ago, the first enzyme reversing this modification was identified very recently. Today we know of two methyltransferases introducing m6A in mRNA--METTL3 and METTL14--and two demethylases that remove it have been identified-FTO (ALKBH9) and ALKBH5. The conserved role of m6A seems to relate to meiosis, and mice lacking ALKBH5 are infertile. While loss-of-function mutation in FTO causes a recessive lethal syndrome, sequence variants in introns of the FTO gene are associated with obesity and type 2 diabetes. PMID:25005745

  12. Modification of chemotherapy by nitroimidazoles

    SciTech Connect

    Siemann, D.W.

    1984-09-01

    The potentiation of chemotherapeutic agents by radiation sensitizers has been extensively studied for several years. There is little doubt that the effectiveness of certain anti-cancer drugs, primarily alkylating agents, can readily be enhanced both in vitro and in vivo through the addition of a sensitizer. While enhanced effects have been observed in certain critical normal tissues, in general most animal model studies have demonstrated a therapeutic gain at large sensitizer doses. This approach to combination therapies therefore appears promising. Yet many questions concerning the interaction between chemotherapeutic agents and radiosensitizers, particularly in the aspects of modification of chemotherapy by nitroimidazoles are reviewed and discussed. These address the importance in chemopotentiation of (i) hypoxia, (ii) alterations in DNA damage and/or repair, (iii) depletion of intracellular sulfhydryls and (iv) modification of drug pharmacokinetics.

  13. Chromatin modifications associated with diabetes.

    PubMed

    Keating, Samuel T; El-Osta, Assam

    2012-08-01

    Accelerated rates of vascular complications are associated with diabetes mellitus. Environmental factors including hyperglycaemia contribute to the progression of diabetic complications. Epidemiological and experimental animal studies identified poor glycaemic control as a major contributor to the development of complications. These studies suggest that early exposure to hyperglycaemia can instigate the development of complications that present later in the progression of the disease, despite improved glycaemic control. Recent experiments reveal a striking commonality associated with gene-activating hyperglycaemic events and chromatin modification. The best characterised to date are associated with the chemical changes of amino-terminal tails of histone H3. Enzymes that write specified histone tail modifications are not well understood in models of hyperglycaemia and metabolic memory as well as human diabetes. The best-characterised enzyme is the lysine specific Set7 methyltransferase. The contribution of Set7 to the aetiology of diabetic complications may extend to other transcriptional events through methylation of non-histone substrates. PMID:22639343

  14. Effect of Atmospheric-Pressure Cold Plasma on Pathogenic Oral Biofilms and In Vitro Reconstituted Oral Epithelium.

    PubMed

    Delben, Juliana Aparecida; Zago, Chaiene Evelin; Tyhovych, Natalia; Duarte, Simone; Vergani, Carlos Eduardo

    2016-01-01

    Considering the ability of atmospheric-pressure cold plasma (ACP) to disrupt the biofilm matrix and rupture cell structure, it can be an efficient tool against virulent oral biofilms. However, it is fundamental that ACP does not cause damage to oral tissue. So, this study evaluated (1) the antimicrobial effect of ACP on single- and dual-species biofilms of Candida albicans and Staphylococcus aureus as well as (2) the biological safety of ACP on in vitro reconstituted oral epithelium. Standardized cell suspensions of each microorganism were prepared for biofilm culture on acrylic resin discs at 37°C for 48 hours. The biofilms were submitted to ACP treatment at 10 mm of plasma tip-to-sample distance during 60 seconds. Positive controls were penicillin G and fluconazole for S. aureus and C. albicans, respectively. The biofilms were analyzed through counting of viable colonies, confocal laser scanning microscopy, scanning electron microscopy and fluorescence microscopy for detection of reactive oxygen species. The in vitro reconstituted oral epithelium was submitted to similar ACP treatment and analyzed through histology, cytotoxocity test (LDH release), viability test (MTT assay) and imunnohistochemistry (Ki67 expression). All plasma-treated biofilms presented significant log10 CFU/mL reduction, alteration in microorganism/biofilm morphology, and reduced viability in comparison to negative and positive controls. In addition, fluorescence microscopy revealed presence of reactive oxygen species in all plasma-treated biofilms. Low cytotoxicity and high viability were observed in oral epithelium of negative control and plasma group. Histology showed neither sign of necrosis nor significant alteration in plasma-treated epithelium. Ki67-positive cells revealed maintenance of cell proliferation in plasma-treated epithelium. Atmospheric-pressure cold plasma is a promissing approach to eliminate single- and dual-species biofilms of C. albicans and S. aureus without having

  15. Effect of Atmospheric-Pressure Cold Plasma on Pathogenic Oral Biofilms and In Vitro Reconstituted Oral Epithelium

    PubMed Central

    Zago, Chaiene Evelin; Tyhovych, Natalia

    2016-01-01

    Considering the ability of atmospheric-pressure cold plasma (ACP) to disrupt the biofilm matrix and rupture cell structure, it can be an efficient tool against virulent oral biofilms. However, it is fundamental that ACP does not cause damage to oral tissue. So, this study evaluated (1) the antimicrobial effect of ACP on single- and dual-species biofilms of Candida albicans and Staphylococcus aureus as well as (2) the biological safety of ACP on in vitro reconstituted oral epithelium. Standardized cell suspensions of each microorganism were prepared for biofilm culture on acrylic resin discs at 37°C for 48 hours. The biofilms were submitted to ACP treatment at 10 mm of plasma tip-to-sample distance during 60 seconds. Positive controls were penicillin G and fluconazole for S. aureus and C. albicans, respectively. The biofilms were analyzed through counting of viable colonies, confocal laser scanning microscopy, scanning electron microscopy and fluorescence microscopy for detection of reactive oxygen species. The in vitro reconstituted oral epithelium was submitted to similar ACP treatment and analyzed through histology, cytotoxocity test (LDH release), viability test (MTT assay) and imunnohistochemistry (Ki67 expression). All plasma-treated biofilms presented significant log10 CFU/mL reduction, alteration in microorganism/biofilm morphology, and reduced viability in comparison to negative and positive controls. In addition, fluorescence microscopy revealed presence of reactive oxygen species in all plasma-treated biofilms. Low cytotoxicity and high viability were observed in oral epithelium of negative control and plasma group. Histology showed neither sign of necrosis nor significant alteration in plasma-treated epithelium. Ki67-positive cells revealed maintenance of cell proliferation in plasma-treated epithelium. Atmospheric-pressure cold plasma is a promissing approach to eliminate single- and dual-species biofilms of C. albicans and S. aureus without having

  16. The response of the macaque tracheobronchial epithelium to acute ozone injury. A quantitative ultrastructural and autoradiographic study

    SciTech Connect

    Wilson, D.W.; Plopper, C.G.; Dungworth, D.L.

    1984-08-01

    The purpose of this study was to evaluate the response of the tracheal epithelium to cytotoxic injury in a primate species that may have an epithelium more representative of that in man than smaller laboratory species. This study evaluated changes in the light-microscopic, surface, and ultrastructural appearance of the tracheobronchial epithelium of bonnet monkeys exposed for 3 or 7 days to 0.64 ppm ozone. Population densities, epithelial volumetric densities, and thymidine labeling indexes were determined for cells from posterior membranous and anterior cartilaginous trachea and mainstem bronchus. Ozone-induced epithelial changes were characterized by decreased numbers of ciliated cells, loss of cilia, and necrosis of ciliated cells. Regional differences in lesion distribution were demonstrated by scanning electron microscopy. Longitudinal streaks of ciliary loss were evident in posterior membranous trachea, but ciliary loss in the ventral trachea was most prominent over the posterior border of the cartilaginous rings. The thymidine labeling index and numbers of necrotic ciliated cells were greater after 3 days than after 7 days of continuous exposure. Foci of stratification were often associated with increased numbers of labeled nuclei in the suprabasal region of the epithelium. The results of this study suggest that small mucous granule cells and intermediate cells are important participants in the repair of chemically injured airway epithelium; stratification and increased amounts of cytoplasmic filament bundles and desmosomal attachments, rather than being evidence of squamous metaplasia or dysplastic change, might be stereotypic responses of airway epithelium to injury; and the ciliated cell population becomes less susceptible to ozone-induced necrosis with continuing exposure.

  17. Choline acetyltransferase and organic cation transporters are responsible for synthesis and propionate-induced release of acetylcholine in colon epithelium.

    PubMed

    Bader, Sandra; Klein, Jochen; Diener, Martin

    2014-06-15

    Acetylcholine is not only a neurotransmitter, but is found in a variety of non-neuronal cells. For example, the enzyme choline acetyltransferase (ChAT), catalyzing acetylcholine synthesis, is expressed by the colonic epithelium of different species. These cells release acetylcholine across the basolateral membrane after luminal exposure to propionate, a short-chain fatty acid. The functional consequence is the induction of chloride secretion, measurable as increase in short-circuit current (Isc) in Ussing chamber experiments. It is unclear how acetylcholine is produced and released by colonic epithelium. Therefore, the aim of the present study was the identification (on mRNA and protein level) and functional characterization (in Ussing chamber experiments combined with HPLC detection of acetylcholine) of transporters/enzymes in the cholinergic system of rat colonic epithelium. Immunohistochemical staining as well as RT-PCR revealed the expression of high-affinity choline transporter, ChAT, carnitine acetyltransferase (CarAT), vesicular acetylcholine transporter (VAChT), and organic cation transporters (OCT 1, 2, 3) in colonic epithelium. In contrast to blockade of ChAT with bromoacetylcholine, inhibition of CarAT with mildronate did not inhibit the propionate-induced increase in Isc, suggesting a predominant synthesis of epithelial acetylcholine by ChAT. Although being expressed, blockade of VAChT with vesamicol was ineffective, whereas inhibition of OCTs with omeprazole and corticosterone inhibited propionate-induced Isc and the release of acetylcholine into the basolateral compartment. In summary, OCTs seem to be involved in regulated acetylcholine release by colonic epithelium, which is assumed to be involved in chemosensing of luminal short-chain fatty acids by the intestinal epithelium.

  18. [Advances in genetic modification technologies].

    PubMed

    Zhang, Baixue; Sun, Qixin; Li, Haifeng

    2015-08-01

    Genetic modification technology is a new molecular tool for targeted genome modification. It includes zinc finger nucleases (ZFN) technology, transcription activator-like effector nucleases (TALEN) technology and clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) (CRISPR-Cas) nucleases technology. All of these nucleases create DNA double-strand breaks (DSB) at chromosomal targeted sites and induce cell endogenous mechanisms that are primarily repaired by the non-homologous end joining (NHEJ) or homologous recombination (HR) pathway, resulting in targeted endogenous gene knock-out or exogenous gene insertion. In recent years, genetic modification technologies have been successfully applied to bacteria, yeast, human cells, fruit fly, zebra fish, mouse, rat, livestock, cynomolgus monkey, Arabidopsis, rice, tobacco, maize, sorghum, wheat, barley and other organisms, showing its enormous advantage in gene editing field. Especially, the newly developed CRISPR-Cas9 system arose more attention because of its low cost, high effectiveness, simplicity and easiness. We reviewed the principles and the latest research progress of these three technologies, as well as prospect of future research and applications.

  19. Epigenetic Modifications in Essential Hypertension

    PubMed Central

    Wise, Ingrid A.; Charchar, Fadi J.

    2016-01-01

    Essential hypertension (EH) is a complex, polygenic condition with no single causative agent. Despite advances in our understanding of the pathophysiology of EH, hypertension remains one of the world’s leading public health problems. Furthermore, there is increasing evidence that epigenetic modifications are as important as genetic predisposition in the development of EH. Indeed, a complex and interactive genetic and environmental system exists to determine an individual’s risk of EH. Epigenetics refers to all heritable changes to the regulation of gene expression as well as chromatin remodelling, without involvement of nucleotide sequence changes. Epigenetic modification is recognized as an essential process in biology, but is now being investigated for its role in the development of specific pathologic conditions, including EH. Epigenetic research will provide insights into the pathogenesis of blood pressure regulation that cannot be explained by classic Mendelian inheritance. This review concentrates on epigenetic modifications to DNA structure, including the influence of non-coding RNAs on hypertension development. PMID:27023534

  20. Protein Modification by Adenine Propenal

    PubMed Central

    2015-01-01

    Base propenals are products of the reaction of DNA with oxidants such as peroxynitrite and bleomycin. The most reactive base propenal, adenine propenal, is mutagenic in Escherichia coli and reacts with DNA to form covalent adducts; however, the reaction of adenine propenal with protein has not yet been investigated. A survey of the reaction of adenine propenal with amino acids revealed that lysine and cysteine form adducts, whereas histidine and arginine do not. Nε-Oxopropenyllysine, a lysine–lysine cross-link, and S-oxopropenyl cysteine are the major products. Comprehensive profiling of the reaction of adenine propenal with human serum albumin and the DNA repair protein, XPA, revealed that the only stable adduct is Nε-oxopropenyllysine. The most reactive sites for modification in human albumin are K190 and K351. Three sites of modification of XPA are in the DNA-binding domain, and two sites are subject to regulatory acetylation. Modification by adenine propenal dramatically reduces XPA’s ability to bind to a DNA substrate. PMID:25211669

  1. Molecular phylogeny of methanogens associated with flagellated protists in the gut and with the gut epithelium of termites.

    PubMed

    Tokura; Ohkuma; Kudo

    2000-09-01

    The molecular phylogeny of methanogenic archaea associated with the flagellated protist species Dinenympha and Microjoenia in the gut of termites, Reticulitermes speratus and Hodotermopsis sjoestedti, and those attached to the gut epithelium was examined based on PCR-amplified small-subunit ribosomal RNA genes. The sequences identified were classified into six groups within the genus Methanobrevibacter, including groups of yet uncharacterized novel species. Closely related methanogens were shared between Microjoenia and some Dinenympha cells in each termite. The methanogens harbored by the flagellates were phylogenetically different from the methanogens associated with the gut epithelium, suggesting that distinct methanogen species showed distinct spatial distributions in the termite gut.

  2. Small intestinal stem cell identity is maintained with functional Paneth cells in heterotopically grafted epithelium onto the colon

    PubMed Central

    Fukuda, Masayoshi; Mizutani, Tomohiro; Mochizuki, Wakana; Matsumoto, Taichi; Nozaki, Kengo; Sakamaki, Yuriko; Ichinose, Shizuko; Okada, Yukinori; Tanaka, Toshihiro; Watanabe, Mamoru

    2014-01-01

    To develop stem cell therapy for small intestinal (SI) diseases, it is essential to determine whether SI stem cells in culture retain their tissue regeneration capabilities. By using a heterotopic transplantation approach, we show that cultured murine SI epithelial organoids are able to reconstitute self-renewing epithelia in the colon. When stably integrated, the SI-derived grafts show many features unique only to the SI but distinct from the colonic epithelium. Our study provides evidence that cultured adult SI stem cells could be a source for cell therapy of intestinal diseases, maintaining their identity along the gastrointestinal tract through an epithelium-intrinsic mechanism. PMID:25128495

  3. DNA modifications: Another stable base in DNA

    NASA Astrophysics Data System (ADS)

    Brazauskas, Pijus; Kriaucionis, Skirmantas

    2014-12-01

    Oxidation of 5-methylcytosine has been proposed to mediate active and passive DNA demethylation. Tracking the history of DNA modifications has now provided the first solid evidence that 5-hydroxymethylcytosine is a stable epigenetic modification.

  4. 40 CFR 60.397 - Modifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Coating Operations § 60.397 Modifications. The following physical or operational changes are not, by themselves, considered modifications of existing facilities: (a) Changes as a result of model...

  5. Mechanosensory Genes Pkd1 and Pkd2 Contribute to the Planar Polarization of Brain Ventricular Epithelium

    PubMed Central

    Herranz-Pérez, Vicente; Nakatani, Jin; Boletta, Alessandra; García-Verdugo, José Manuel

    2015-01-01

    Directional beating of ependymal (E) cells' cilia in the walls of the ventricles in the brain is essential for proper CSF flow. E cells display two forms of planar cell polarity (PCP): rotational polarity of individual cilium and translational polarity (asymmetric positioning of cilia in the apical area). The orientation of individual E cells varies according to their location in the ventricular wall (location-specific PCP). It has been hypothesized that hydrodynamic forces on the apical surface of radial glia cells (RGCs), the embryonic precursors of E cells, could guide location-specific PCP in the ventricular epithelium. However, the detection mechanisms for these hydrodynamic forces have not been identified. Here, we show that the mechanosensory proteins polycystic kidney disease 1 (Pkd1) and Pkd2 are present in primary cilia of RGCs. Ablation of Pkd1 or Pkd2 in Nestin-Cre;Pkd1flox/flox or Nestin-Cre;Pkd2flox/flox mice, affected PCP development in RGCs and E cells. Early shear forces on the ventricular epithelium may activate Pkd1 and Pkd2 in primary cilia of RGCs to properly polarize RGCs and E cells. Consistently, Pkd1, Pkd2, or primary cilia on RGCs were required for the proper asymmetric localization of the PCP protein Vangl2 in E cells' apical area. Analyses of single- and double-heterozygous mutants for Pkd1 and/or Vangl2 suggest that these genes function in the same pathway to establish E cells' PCP. We conclude that Pkd1 and Pkd2 mechanosensory proteins contribute to the development of brain PCP and prevention of hydrocephalus. SIGNIFICANCE STATEMENT This study identifies key molecules in the development of planar cell polarity (PCP) in the brain and prevention of hydrocephalus. Multiciliated ependymal (E) cells within the brain ventricular epithelium generate CSF flow through ciliary beating. E cells display location-specific PCP in the orientation and asymmetric positioning of their cilia. Defects in this PCP can result in hydrocephalus. Hydrodynamic

  6. Energy conservation potential of surface modification technologies

    SciTech Connect

    Le, H.K.; Horne, D.M.; Silberglitt, R.S.

    1985-09-01

    This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

  7. Modification Of Gear Teeth To Reduce Vibrations

    NASA Technical Reports Server (NTRS)

    Townsend, Dennis P.; Oswald, Fred B.; Lin, Hsiang Hsi

    1990-01-01

    Computer simulations yield data useful in designing for low noise. Effects of modifications in shape of gear teeth upon static transmission error and dynamic loading of gears now analyzed systematically. Design curves generated by conducting numerical simulations of dynamic effects at successive incremental modifications of gear systems operated at various applied loads. Modifications that result in minimum dynamic effect determined from design curves.

  8. Modification: A Leader Skill in Group Work.

    ERIC Educational Resources Information Center

    Clark, Arthur J.

    1995-01-01

    Modification mitigates negative feedback by immediately attempting to improve the feedback's level of acceptability. This article introduces modification as a group-leader skill necessary for the processing of messages containing both counterproductive and productive elements. Describes the value and application of modification in group work. (RJM)

  9. Transcriptional changes during neuronal death and replacement in the olfactory epithelium.

    PubMed

    Shetty, Ranjit S; Bose, Soma C; Nickell, Melissa D; McIntyre, Jeremy C; Hardin, Debra H; Harris, Andrew M; McClintock, Timothy S

    2005-12-01

    The olfactory epithelium has the unusual ability to replace its neurons.We forced replacement of mouse olfactory sensory neurons by bulbectomy. Microarray, bioinformatics, and in situ hybridization techniques detected a rapid shift in favor of pro-apoptotic proteins, a progressive immune response by macrophages and dendritic cells, and identified or predicted 439 mRNAs enriched in olfactory sensory neurons, including gene silencing factors and sperm flagellar proteins. Transcripts encoding cell cycle regulators, axonogenesis proteins, and transcription factors and signaling proteins that promote proliferation and differentiation were increased at 5-7 days after bulbectomy and were expressed by basal progenitor cells or immature neurons. The transcription factors included Nhlhl, Hes6, Lmycl, c-Myc, Mxd4, Idl,Nmycl, Cited2, c-Myb, Mybll, Tead2, Dpl, Gata2, Lmol, and Soxll. The data reveal significant similarities with embryonic neurogenesis and make several mechanistic predictions, including the roles of the transcription factors in the olfactory sensory neuron lineage.

  10. Distribution of melanosomes across the retinal pigment epithelium of a hooded rat: implications for light damage

    SciTech Connect

    Howell, W.L.; Rapp, L.M.; Williams, T.P.

    1982-02-01

    Distribution of melanosomes across the retinal pigment epithelium of hooded rats (Long-Evans) is studied at the light microscopic and electron microscopic levels. This distribution is shown to be nonuniform: more melanosomes exist in the periphery than elsewhere and, importantly, there are very few melanosomes in a restricted area of the central portion of the superior hemisphere compared with the corresponding part of the inferior hemisphere. The region with fewest melanosomes is precisely the one that is highly susceptible to light damage. Because this region is the same in both pigmented and albino eyes, the paucity of melanin in this region is not the cause of its great sensitivity to light damage. Nor does light cause the nonuniform distribution of melanin. A possible explanation, involving a proposed vestigial tapetum, is given in order to explain the correlation of melanosome counts and sensitivity to light damage.

  11. Demonstration of carboxylesterase in cytology samples of human nasal respiratory epithelium

    SciTech Connect

    Rodgers, D.A.; Nikula, K.J.; Avila, K.

    1995-12-01

    The epithelial lining of the nasal airways is a target for responses induced by a variety of toxicant exposures. The high metabolic capacity of this tissue has been suggested to play a role in both protection of the airways through detoxication of certain toxicants, as well as in activation of other compounds to more toxic metabolites. Specifically, nasal carboxylesterase (CE) has been shown to mediate the toxicity of inhaled esters and acrylates by converting them to more toxic acid and alcohol metabolites which can be cytotoxic and/or carcinogenic to the nasal mucosa. Due to difficulties in extrapolating rodent models to human, new paradigms using human cells and tissues are essential to understanding and evaluating the metabolic processes in human nasal epithelium.

  12. High Fructose Diet inducing diabetes rapidly impacts olfactory epithelium and behavior in mice

    PubMed Central

    Rivière, Sébastien; Soubeyre, Vanessa; Jarriault, David; Molinas, Adrien; Léger-Charnay, Elise; Desmoulins, Lucie; Grebert, Denise; Meunier, Nicolas; Grosmaitre, Xavier

    2016-01-01

    Type 2 Diabetes (T2D), a major public health issue reaching worldwide epidemic, has been correlated with lower olfactory abilities in humans. As olfaction represents a major component of feeding behavior, its alteration may have drastic consequences on feeding behaviors that may in turn aggravates T2D. In order to decipher the impact of T2D on the olfactory epithelium, we fed mice with a high fructose diet (HFruD) inducing early diabetic state in 4 to 8 weeks. After only 4 weeks of this diet, mice exhibited a dramatic decrease in olfactory behavioral capacities. Consistently, this decline in olfactory behavior was correlated to decreased electrophysiological responses of olfactory neurons recorded as a population and individually. Our results demonstrate that, in rodents, olfaction is modified by HFruD-induced diabetes. Functional, anatomical and behavioral changes occurred in the olfactory system at a very early stage of the disease. PMID:27659313

  13. Extracellular matrix stiffness and composition jointly regulate the induction of malignant phenotypes in mammary epithelium.

    PubMed

    Chaudhuri, Ovijit; Koshy, Sandeep T; Branco da Cunha, Cristiana; Shin, Jae-Won; Verbeke, Catia S; Allison, Kimberly H; Mooney, David J

    2014-10-01

    In vitro models of normal mammary epithelium have correlated increased extracellular matrix (ECM) stiffness with malignant phenotypes. However, the role of increased stiffness in this transformation remains unclear because of difficulties in controlling ECM stiffness, composition and architecture independently. Here we demonstrate that interpenetrating networks of reconstituted basement membrane matrix and alginate can be used to modulate ECM stiffness independently of composition and architecture. We find that, in normal mammary epithelial cells, increasing ECM stiffness alone induces malignant phenotypes but that the effect is completely abrogated when accompanied by an increase in basement-membrane ligands. We also find that the combination of stiffness and composition is sensed through β4 integrin, Rac1, and the PI3K pathway, and suggest a mechanism in which an increase in ECM stiffness, without an increase in basement membrane ligands, prevents normal α6β4 integrin clustering into hemidesmosomes.

  14. Extracellular matrix stiffness and composition jointly regulate the induction of malignant phenotypes in mammary epithelium

    NASA Astrophysics Data System (ADS)

    Chaudhuri, Ovijit; Koshy, Sandeep T.; Branco da Cunha, Cristiana; Shin, Jae-Won; Verbeke, Catia S.; Allison, Kimberly H.; Mooney, David J.

    2014-10-01

    In vitro models of normal mammary epithelium have correlated increased extracellular matrix (ECM) stiffness with malignant phenotypes. However, the role of increased stiffness in this transformation remains unclear because of difficulties in controlling ECM stiffness, composition and architecture independently. Here we demonstrate that interpenetrating networks of reconstituted basement membrane matrix and alginate can be used to modulate ECM stiffness independently of composition and architecture. We find that, in normal mammary epithelial cells, increasing ECM stiffness alone induces malignant phenotypes but that the effect is completely abrogated when accompanied by an increase in basement-membrane ligands. We also find that the combination of stiffness and composition is sensed through β4 integrin, Rac1, and the PI3K pathway, and suggest a mechanism in which an increase in ECM stiffness, without an increase in basement membrane ligands, prevents normal α6β4 integrin clustering into hemidesmosomes.

  15. Photoinduced changes in subcellular structures of the retinal pigment epithelium from the Japanese quail Coturnix japonica.

    PubMed

    Zak, P P; Serezhnikova, N B; Pogodina, L S; Trofimova, N N; Gur'eva, T S; Dadasheva, O A

    2015-06-01

    Fifteen-week-old sexually mature female Japanese quails (Coturnix japonica) grown under various lighting conditions were used in the study. It was found that the number of mitochondria and phagosomes was increased by 1.5-fold in the retinal pigment epithelium from birds reared for 95 days under blue light (440-470 nm) vs. reduced blue light component conditions. Also, it was found that egg production was increased by 15% in birds reared under blue light compared to other lightning conditions. Thus, we concluded that blue light conditions resulted in elevating metabolic activity and accelerating pace of life in Japanese quails. It is assumed that the blue light-induced effects are probably due to inhibition of melatonin synthesis. PMID:26531024

  16. Lipofuscin in retinal pigment epithelium of rhesus monkey: lack of diminution with centrophenoxine treatment.

    PubMed

    Andrews, L D; Brizzee, K R

    1986-01-01

    An experiment was performed to test the ability of Centrophenoxine to reduce the amount of lipofuscin (age pigment) in the retinal pigment epithelium (RPE) of aged rhesus monkeys. Centrophenoxine is reputed to have this action in neurons of lower mammals. Quantitative electron microscopic analysis was performed on sections from the perifovea of ten rhesus monkeys, all approximately 20 years of age. Four of the animals received 80 mg/kg Centrophenoxine (IM injection) daily for 12 weeks. No significant difference between the treated and control groups could be demonstrated statistically (Mann-Whitney U-test) either in the fraction of RPE cell cytoplasm occupied by lipofuscin granules or in the average size of the granules.

  17. Maturation status of small intestine epithelium in rats deprived of dietary nucleotides.

    PubMed

    Ortega, M A; Gil, A; Sánchez-Pozo, A

    1995-01-01

    We describe the changes of several brush-border enzymatic activities in different subpopulations of epithelial cells, separated sequentially from the villus tip-to-crypt axis of the small intestine, induced by deprivation of dietary nucleotides for different periods of time in adult rats. Deprivation of dietary nucleotides lead to a decrease in the content and specific activity of alkaline phosphatase, leucine-aminopeptidase, maltase, sucrase and lactase in the villus tip, but had little effect on the crypt zone. The effect of the nucleotide deprivation on the enzymatic activity progressively increased towards the tip of the villus. Since these enzymes are maturation markers of the intestinal cells, these results support the idea that dietary nucleotides affect the maturation status of small-intestine epithelium.

  18. Prohibitin as the Molecular Binding Switch in the Retinal Pigment Epithelium.

    PubMed

    Sripathi, Srinivas R; Sylvester, O'Donnell; He, Weilue; Moser, Trevor; Um, Ji-Yeon; Lamoke, Folami; Ramakrishna, Wusirika; Bernstein, Paul S; Bartoli, Manuela; Jahng, Wan Jin

    2016-02-01

    Previously, our molecular binding study showed that prohibitin interacts with phospholipids, including phosphatidylinositide and cardiolipin. Under stress conditions, prohibitin interacts with cardiolipin as a retrograde response to activate mitochondrial proliferation. The lipid-binding switch mechanism of prohibitin with phosphatidylinositol-3,4,5-triphosphate and cardiolipin may suggest the role of prohibitin effects on energy metabolism and age-related diseases. The current study examined the region-specific expressions of prohibitin with respect to the retina and retinal pigment epithelium (RPE) in age-related macular degeneration (AMD). A detailed understanding of prohibitin binding with lipids, nucleotides, and proteins shown in the current study may suggest how molecular interactions control apoptosis and how we can intervene against the apoptotic pathway in AMD. Our data imply that decreased prohibitin in the peripheral RPE is a significant step leading to mitochondrial dysfunction that may promote AMD progression. PMID:26661103

  19. Extremely elongated mitochondria in ionocytes of the saccular epithelium of a teleost, Oreochromis mossambicus (Cichlidae)

    NASA Astrophysics Data System (ADS)

    Muders, K.; Anken, R.; Ibsch, M.; Rahmann, H.

    2004-01-01

    Unusually large mitochondria are a rather scarce feature in normal biological tissue and string-like giant mitochondria have hitherto not been reported in animals. Investigating the role of inner ear ionocytes for otolith growth, large ionocytes of the saccular epithelium of the cichlid fish Oreochromis mossambicus were analyzed by imaging of thick sections with energy-filtering transmission electron microscopy. We report here that ionocytes do not contain numerous small-sized mitochondria as has been suggested earlier but rather few, extremely elongated megamitochondria. Since the particular mitochondrial structure is important for normal cell function, such megamitochondria possibly reflect a functional advantage in the context of the presumed role of teleostean ionocytes in regulating the composition of the endolymphatic fluid.

  20. Pseudotumoral and Multiple Retinal Pigment Epithelium Proliferation in Vogt-Koyanagi-Harada Disease.

    PubMed

    Yepez, Juan B; Murati, Felipe; Petitto, Michele; Arevalo, J Fernando

    2015-01-01

    We report a case of pseudotumoral retinal pigment epithelium (RPE) proliferation in Vogt-Koyanagi-Harada (VKH) disease, in a 50-year-old female who presented with a juxtapapillary and peripheral subretinal hyperpigmented lesions in the left eye and "sunset glow fundus," hyperpigmented striae, and multiple atrophic chorioretinal spots in the periphery. The darkly pigmented exuberant larger subretinal mass extended to the periphery with associated subretinal fibrosis. This patient demonstrated the entire clinical presentation of VKH disease, which tends to course with a chronic, bilateral, granulomatous panuveitis and exudative retinal detachment associated with poliosis, vitiligo, alopecia, and central nervous system and auditory signs. Our case is unique for the presence of exuberant, pseudotumoral RPE proliferation at the juxtapapillary region and peripheral area. Although this complication has rarely been reported, a high index of suspicion is warranted for early diagnosis and avoids unnecessary treatments of a pseudotumor. PMID:26509089