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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 ... Epithelium. In: Kierszenbaum AL, Tres LL. Histology and Cell Biology - An Introduction to Pathology , 3rd ed. Philadelphia, ...

  2. Modification of disodium cromoglycate passage across lung epithelium in vitro via incorporation into polymeric microparticles.

    PubMed

    Haghi, Mehra; Salama, Rania; Traini, Daniela; Bebawy, Mary; Young, Paul M

    2012-03-01

    Two microparticle systems containing disodium cromoglycate (DSCG) alone or with polyvinyl alcohol (DSCG/PVA) were produced via spray drying and compared in terms of their physicochemical characteristics, aerosol performance and drug uptake across a pulmonary epithelial cell line (Calu-3), cultured under air interface conditions. The particle size distribution of DSCG and DSCG/PVA were similar, of spherical geometry, amorphous and suitable for inhalation purposes. Aerosolisation studies using a modified twin-stage impinger showed the DSCG/PVA to have greater aerosol performance than that of DSCG alone. Aerosol particles of DSCG and DSCG/PVA were deposited onto the surface of the Calu-3 air interface epithelium monolayer and the drug uptake from apical to basal directions measured over time. Drug uptake was measured across a range of doses to allow comparison of equivalent drug and powder mass deposition. Analysis of the data indicated that the percentage cumulative drug uptake was independent of the mass of powder deposited, but dependent on the formulation. Specifically, with the formulation containing DSCG, the diffusion rate was observed to change with respect to time (indicative of a concentration-dependent diffusion process), whilst DSCG/PVA showed a time-independent drug uptake (suggesting a zero-order depot release). PMID:22203523

  3. Nitrite Modification of Extracellular Matrix Alters CD46 Expression and VEGF Release in Human Retinal Pigment Epithelium

    PubMed Central

    Fields, Mark A.; Cai, Hui; Bowrey, Hannah E.; Moreira, Ernesto F.; Beck Gooz, Monika; Kunchithapautham, Kannan; Gong, Jie; Vought, Emma; Del Priore, Lucian V.

    2015-01-01

    Purpose Loss of CD46 has recently been implicated in choroidal neovascularization in mice. Herein we investigated the effect of nitrite modification of the extracellular matrix (ECM) as an in vitro model of “aging” and its effect on CD46 expression and vascular endothelial growth factor (VEGF) release in cocultured human retinal pigment epithelium (RPE). Methods ARPE-19 cells were plated onto RPE-derived ECM conditions (untreated; nitrite modified; nitrite modified followed by washing with Triton X-100; or nitrite modified followed by washing with Triton X-100 and coated with extracellular matrix ligands). Cells were cultured for 7 days and CD46 expression was analyzed by immunohistochemistry and Western blot. Additionally, CD46 short interfering RNA (siRNA) was transfected into ARPE-19 cells, and VEGF levels were determined by ELISA. Finally, in the same ECM conditions, ARPE-19 cells were challenged with normal human serum and VEGF levels determined by ELISA. Results CD46 is expressed on the basolateral surface of ARPE-19 cells on RPE-derived ECM. Nitrite modification of ECM reduced the expression of CD46 on ARPE-19 cells by 0.5-fold (P = 0.003) and increased VEGF release in ARPE-19 cells by 1.7-fold (P < 0.001). CD46 knockdown also increased release of VEGF on the apical and basal sides of ARPE-19 cells in culture by 1.3- (P = 0.012) and 1.2-fold (P = 0.017), respectively. Conclusions Nitrite modification of the ECM decreased CD46 expression and increased the release of VEGF from ARPE-19 cells. Changes in CD46 expression may lead to changes in VEGF and play a pathologic role in the development of age-related macular degeneration. PMID:26161984

  4. 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

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

    PubMed

    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 CD14(high)CD16- 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+CD27(lo)) 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

  6. 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

  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. 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

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

    PubMed Central

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

    2014-01-01

    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. PMID:24785116

  11. One-step treatment of proximal hypospadias by the autologous graft of cultured urethral epithelium.

    PubMed

    Romagnoli, G; De Luca, M; Faranda, F; Franzi, A T; Cancedda, R

    1993-10-01

    Surgical management of severe proximal hypospadias or long strictures of the posterior urethra is a difficult clinical task. Often, the therapeutic approach involves the autologous graft of free flaps of bladder or oral mucosa. We recently reported the use of autologous graft of cultured squamous urethral epithelium during urethroplasty in patients with severe proximal hypospadias. The main limitation to the widespread use of cultured epithelium was the long hospitalization due to the requirement of 2 surgical steps. We now report a substantial modification of the surgical procedure which allows for rapid 1-step urethroplasty. Cultured squamous urethral epithelium is tubularized in vitro with the aid of a tubular polytetrafluoroethylene (Gore-Tex) support and 1-step urethroplasty is performed within 30 minutes. Results obtained in 8 patients are presented. PMID:8371392

  12. Optimization of silk films as substrate for functional corneal epithelium growth.

    PubMed

    Jia, Liang; Ghezzi, Chiara E; Kaplan, David L

    2016-02-01

    The corneal epithelium is the first cellular barrier to protect the cornea. Thus, functional tissue engineering of the corneal epithelium is a strategy for clinical transplantation. In this study, the optimization of silk films (SFs) as substrates for functional human corneal epithelium growth was investigated with primary human corneal epithelial cells on SFs, poly-D-lysine (PDL) coated SFs, arginine-glycine-aspartic acid (RGD) modified SFs and PDL blended SFs. PDL coated SFs significantly promoted cell adhesion at early phases in comparison to the other study groups, while PDL blended SF significantly promoted cell migration in a "wound healing" model. All film modifications promoted cell proliferation and viability, and a multi-layered epithelium was achieved in 4 weeks of culture. The epithelia formed were tightly apposed and maintained an intact barrier function against rose bengal dye penetration. The results suggested that a differentiated human corneal epithelium can be established with primary corneal epithelial cells on SFs in vitro, by optimizing SF composition with PDL. PMID:25891207

  13. 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. PMID:22294437

  14. The skin of fish as a transport epithelium: a review.

    PubMed

    Glover, Chris N; Bucking, Carol; Wood, Chris M

    2013-10-01

    The primary function of fish skin is to act as a barrier. It provides protection against physical damage and assists with the maintenance of homoeostasis by minimising exchange between the animal and the environment. However in some fish, the skin may play a more active physiological role. This is particularly true in species that inhabit specialised environmental niches (e.g. amphibious and air-breathing fish such as the lungfish), those with physiological characteristics that may subvert the need for the integument as a barrier (e.g. the osmoconforming hagfish), and/or fish with anatomical modifications of the epidermis (e.g. reduced epithelial thickness). Using examples from different fish groups (e.g. hagfishes, elasmobranchs and teleosts), the importance of fish skin as a transport epithelium for gases, ions, nitrogenous waste products, and nutrients was reviewed. The role of the skin in larval fish was also examined, with early life stages often utilising the skin as a surrogate gill, prior to the development of a functional branchial epithelium. PMID:23660826

  15. 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

  16. 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.

  17. Retinal pigment epithelium in incontinentia pigmenti.

    PubMed

    Mensheha-Manhart, O; Rodrigues, M M; Shields, J A; Shannon, G M; Mirabelli, R P

    1975-04-01

    An 18-month-old white girl with incontinentia pigmenti presented clinically with leukokoria of the right eye. B-scan ultrasound demonstrated a retrolental mass consistent with a detached retina. Histologic examination of the skin revealed changes compatible with the intermediate verrucous phase of the disease. Microscopic examination of the right eye showed retinal detachment and nodular proliferation of the retinal pigment epithelium. The nodules contained macrophages laden with melanin and lipofuscin. An unusually large amount of lipofuscin was present for a child of this age. The basic pigmentary abnormality may affect the retinal pigment epithelium, resulting in changes in the overlying neurosensory retina that may lead to the retinal dysplasia or retinal detachemnt often associated with this condition. PMID:1119517

  18. 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

  19. Mechanically patterning the embryonic airway epithelium.

    PubMed

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

    2015-07-28

    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

  20. Remodeling of the Fetal Collecting Duct Epithelium

    PubMed Central

    Hiatt, Michael J.; Ivanova, Larissa; Toran, Nuria; Tarantal, Alice F.; Matsell, Douglas G.

    2010-01-01

    Congenital urinary tract obstruction induces changes to the renal collecting duct epithelium, including alteration and depletion of intercalated cells. To study the effects of obstruction on the ontogeny of intercalated cell development, we examined normal and obstructed human fetal and postnatal kidneys. In the normal human fetal kidney, intercalated cells originated in the medullary collecting duct at 8 weeks gestation and remained most abundant in the inner medulla throughout gestation. In the cortex, intercalated cells were rare at 18 and 26 weeks gestation and observed at low abundance at 36 weeks gestation. Although early intercalated cells exhibit an immature phenotype, Type A intercalated cells predominated in the inner and outer medullae at 26 and 36 weeks gestation with other intercalated cell subtypes observed rarely. Postnatally, the collecting duct epithelium underwent a remodeling whereby intercalated cells become abundant in the cortex yet absent from the inner medulla. In 18-week obstructed kidneys with mild to moderate injury, the intercalated cells became more abundant and differentiated than the equivalent age-matched normal kidney. In contrast, more severely injured ducts of the late obstructed kidney exhibited a significant reduction in intercalated cells. These studies characterize the normal ontogeny of human intercalated cell development and suggest that obstruction induces premature remodeling and differentiation of the fetal collecting duct epithelium. PMID:20035053

  1. 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

  2. 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.

  3. Behavior modification.

    PubMed

    Pelham, W E; Fabiano, G A

    2000-07-01

    Attention deficit/hyperactivity disorder (ADHD) is a chronic and substantially impairing disorder. This means that treatment must also be chronic and substantial. Behavior Modification, and in many cases, the combination of behavior modification and stimulant medication, is a valid, useful treatment for reducing the pervasive impairment experienced by children with ADHD. Based on the research evidence reviewed, behavior modification should be the first line of treatment for children with ADHD. PMID:10944662

  4. 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

  5. Lectin reactivities as intermediate biomarkers in premalignant colorectal epithelium.

    PubMed

    Boland, C R; Martin, M A; Goldstein, I J

    1992-01-01

    Normal colonic epithelial cells undergo maturation as they traverse the crypt to the lumenal surface. The binding of lectins to goblet cell mucins and other glycoconjugates changes as the cells migrate and differentiate. Additional stepwise modifications in glycoconjugate expression occur in premalignant and malignant neoplasms that may be detected by lectin binding studies. The lectins Dolichos biflorus agglutinin (DBA) and soybean agglutinin (SBA) have been developed as markers of differentiation in normal-appearing colonic epithelium. Using a quantitative biometric system to score tissues, reduced levels of lectin binding have been found in rectal tissue from patients with familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer. The lectin Amaranthus caudatus agglutinin (ACA) binds to a cytoplasmic glycoconjugate expressed at the base of the colonic crypt and serves as a possible proliferation marker in the distal, but not proximal, colon. ACA binding increases in tandem with increased levels of proliferation (using BrdU incorporation) in neoplastic tissues. Binding by the peanut lectin (PNA) occurs late in the adenoma-to-carcinoma sequence--in larger adenomas and in cancers--and serves as a marker of advancing neoplasia. Lectins identify the stepwise changes that occur during normal differentiation, proliferation and in advancing neoplasia. By selecting the appropriate probe, biomarkers may be developed for early, intermediate, and late events in colorectal cancer. PMID:1469891

  6. Histatin-1 Expression in Human Lacrimal Epithelium

    PubMed Central

    Pasha, Zeeshan; Jaboori, Assraa Jassim; Jassim, Sarmad H.; Jain, Sandeep; Aakalu, Vinay K.

    2016-01-01

    Background Study of human lacrimal cell biology is limited by poor access to tissue samples, heterogeneous cell composition of tissue and a lack of established lacrimal epithelial markers. In order to further our understanding of lacrimal cell biology, we sought to find a better marker for human lacrimal epithelial cells, compared to what has been reported in the literature. Methods We utilized human Muller’s muscle conjunctival resection (MMCR) specimens containing accessory lacrimal gland (ALG) and cadaveric main lacrimal gland (MLG) as sources of lacrimal tissue. Candidate markers were sought using human ALG tissue from MMCR specimens, isolated by laser capture microdissection (LCM). Affymetrix® analysis was performed on total RNA isolated from FFPE samples to profile transcription in ALG. MMCR tissue sections were assessed by immunofluorescence using antibodies for histatin-1, lactoferrin, E-cadherin (E-cad) and alpha-smooth muscle actin (ASMA). Reverse transcriptase polymerase chain reaction (RT-PCR) analysis was performed to analyze the expression of histatin-1, E-cad and lactoferrin from cadaveric MLG. Results Histatin-1 is expressed in ALG and MLG, localizes to lacrimal epithelium, and to a greater degree than do other putative lacrimal epithelial markers. Conclusions Histatin-1 is a good marker for human lacrimal epithelium in ALG and MLG and can be used to identify lacrimal cells in future studies. PMID:26824896

  7. Human Reconstituted Nasal Epithelium, a promising in vitro model to assess impacts of environmental complex mixtures.

    PubMed

    Bardet, Gaëlle; Mignon, Virginie; Momas, Isabelle; Achard, Sophie; Seta, Nathalie

    2016-04-01

    Considering the impact of respiratory diseases around the world, appropriate experimental tools to help understand the mechanisms involved in such diseases are becoming essential. Our aim was to investigate the cellular and morphological reactivity of a human Reconstituted Nasal Epithelium (hRNE) to evaluate the impact of environmental complex mixture (ECM), with tobacco smoke as a model, after three weeks of repeated exposures. Staining of hRNE showed a multilayered ciliated epithelium, with a regular cilia beats, and a mucus production. When hRNE was exposed to ECM for 5 min once or twice a week, during 3 weeks, significant changes occurred: IL-8 production significantly increased 24h after the first exposure compared with Air-exposure and only during the first week, without any loss of tissue integrity. Immunostaining of F-actin cytoskeleton showed a modification in cellular morphology (number and diameter). Taken together our results indicate that hRNE is well suited to study the cellular and morphological effects of repeated exposures to an environmental complex mixture. Human reconstituted epithelium models are currently the best in vitro representation of human respiratory tract physiology, and also the most robust for performing repeated exposures to atmospheric pollutants. PMID:26631767

  8. 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) ...

  9. Neuropilins: expression and roles in the epithelium.

    PubMed

    Wild, Jonathan R L; Staton, Carolyn A; Chapple, Keith; Corfe, Bernard M

    2012-04-01

    Initially found expressed in neuronal and then later in endothelial cells, it is well established that the transmembrane glycoproteins neuropilin-1 (NRP1) and neuropilin-2 (NRP2) play essential roles in axonal growth and guidance and in physiological and pathological angiogenesis. Neuropilin expression and function in epithelial cells has received little attention when compared with neuronal and endothelial cells. Overexpression of NRPs is shown to enhance growth, correlate with invasion and is associated with poor prognosis in various tumour types, especially those of epithelial origin. The contribution of NRP and its ligands to tumour growth and metastasis has spurred a strong interest in NRPs as novel chemotherapy drug targets. Given NRP's role as a multifunctional co-receptor with an ability to bind with disparate ligand families, this has sparked new areas of research implicating NRPs in diverse biological functions. Here, we review the growing body of research demonstrating NRP expression and role in the normal and neoplastic epithelium. PMID:22414290

  10. Adenocarcinoma of the pigmented ciliary epithelium

    PubMed Central

    Sukeda, Aoi; Mori, Taisuke; Suzuki, Shigenobu; Ochiai, Atsushi

    2014-01-01

    Adenocarcinoma of the pigmented ciliary epithelium is an exceptionally rare eye tumour, with only a few cases reported to date. We encountered such a case in a 50-year-old woman who reported seeing floaters in her right eye. Fundus examination and MRI revealed an elevated lesion located in the ciliary body compressing the lens. The ciliary body was resected under the diagnosis of ciliary adenoma. On histological examination, the tumour exhibited epithelial features with glandular formation and moderate nuclear pleomorphism. The tumour invaded the subepithelial stroma of the ciliary body. Immunohistochemical findings were positive for cytokeratin OSCAR, AE1/AE3, CK7, EMA, S100, Melan A, HMB45, and microphthalmia-associated transcription factor. PMID:25015166

  11. Ultrastructure of gingival epithelium in chronic gingivitis.

    PubMed

    Lushnikova, E L; Nepomnyashchikh, L M; Oskolsky, G I; Jurkevich, N V

    2012-03-01

    We studied ultrastructural reorganization of the gingival mucosa in chronic gingivitis. It was found that chronic inflammation leads to significant intracellular reorganization of epitheliocytes in the basal and prickle cell layers of gingival epithelium and their pronounced structural and functional heterogeneity. The main ultrastructural alterations of epitheliocytes in the basal and prickle cell layers include pronounced vacuolization of the perinuclear zone (partial necrosis), formation of thick tonofilament bundles, focal lysis and sequestration of glycogen, and destruction and reduction of intracellular junctions in some cases accompanied by acantholytic alterations. Chronic inflammation in the gingival mucosa induced extensive remodeling of the lamina propria manifested in multiplication of the basement membrane and obturation of blood vessels with collagen fibrils. PMID:22803154

  12. 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

  13. Velocity fields in a collectively migrating epithelium.

    PubMed

    Petitjean, L; Reffay, M; Grasland-Mongrain, E; Poujade, M; Ladoux, B; Buguin, A; Silberzan, P

    2010-05-19

    We report quantitative measurements of the velocity field of collectively migrating cells in a motile epithelium. The migration is triggered by presenting free surface to an initially confluent monolayer by using a microstencil technique that does not damage the cells. To avoid the technical difficulties inherent in the tracking of single cells, the field is mapped using the technique of particle image velocimetry. The main relevant parameters, such as the velocity module, the order parameter, and the velocity correlation function, are then extracted from this cartography. These quantities are dynamically measured on two types of cells (collectively migrating Madin-Darby canine kidney (MDCK) cells and fibroblastlike normal rat kidney (NRK) cells), first as they approach confluence, and then when the geometrical constraints are released. In particular, for MDCK cells filling up the patterns, we observe a sharp decrease in the average velocity after the point of confluence, whereas the densification of the monolayer is much more regular. After the peeling off of the stencil, a velocity correlation length of approximately 200 microm is measured for MDCK cells versus only approximately 40 microm for the more independent NRK cells. Our conclusions are supported by parallel single-cell tracking experiments. By using the biorthogonal decomposition of the velocity field, we conclude that the velocity field of MDCK cells is very coherent in contrast with the NRK cells. The displacements in the fingers arising from the border of MDCK epithelia are very oriented along their main direction. They influence the velocity field in the epithelium over a distance of approximately 200 microm. PMID:20441742

  14. 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

  15. Cytolethal Distending Toxin Damages the Oral Epithelium of Gingival Explants

    PubMed Central

    Damek-Poprawa, M.; Haris, M.; Volgina, A.; Korostoff, J.; DiRienzo, J.M.

    2011-01-01

    The cytolethal distending toxin (Cdt), expressed by the periodontal pathogen Aggregatibacter actinomycetemcomitans, inhibits the proliferation of cultured epithelial cells by arresting the cell cycle. The gingival epithelium is an early line of defense against microbial assault. When damaged, bacteria collectively gain entry into underlying connective tissue where microbial products can affect infiltrating inflammatory cells, leading to the destruction of the attachment apparatus. Histological evaluation of rat and healthy human gingival tissue exposed ex vivo to the Cdt for 36 and 18 hours, respectively, revealed extensive detachment of the keratinized outer layer and distention of spinous and basal cells in the oral epithelium. Treated human tissue also exhibited disruption of rete pegs and dissolution of cell junctions. Cells in the connective tissue appeared unaffected. Primary gingival epithelial cells, but not gingival fibroblasts, isolated from the same healthy human tissue were cell-cycle-arrested when treated with the toxin. These findings provide new evidence that the Cdt severely damages the oral epithelium, ex vivo, by specifically targeting epithelial cells, in situ. The Cdt shows preferential targeting of the epithelium as opposed to connective tissue in animal and human gingival explant models. Abbreviations: cytolethal distending toxin (Cdt), connective tissue (CT), 4′,6-diamidino-2-phenylindole (DAPI), human gingival epithelial cells (HGEC), human gingival explants (HGX), human gingival fibroblasts (HGF), junctional epithelium (JE), oral epithelium (OE), rete pegs (RP), sulcular epithelium (SE) PMID:21471326

  16. 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

  17. 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

  18. Stroma–epithelium crosstalk in prostate cancer

    PubMed Central

    Niu, Yi-Nong; Xia, Shu-Jie

    2009-01-01

    The critical role played by stroma–epithelium crosstalk in carcinogenesis and progression of prostate cancer has been increasingly recognized. These interactions are mediated by a variety of paracrine factors secreted by cancer cells and/or stromal cells. In human prostate cancer, reactive stroma is characterized by an increase in myofibroblasts and a corresponding amplification of extracellular matrix production and angiogenesis. Permanent genetic mutations have been reported in stromal cells as well as in tumour cells. Transforming growth factor-β, vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor signalling pathways are involved in the process of angiogenesis, whereas hepatocyte growth factor, insulin-like growth factor-1, epidermal growth factor, CXC12 and Interleukin-6 play active roles in the progression, androgen-independent conversion and distal metastasis of prostate cancer. Some soluble factors have reciprocal interactions with androgens and the androgen receptor (AR), and can even activate AR in the absence of the androgen ligand. In this article, we review the complex interactions between cancer cells and the surrounding microenvironment, and discuss the potential therapeutic targets in the stromal compartment of prostate cancer. PMID:19098934

  19. 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.

  20. 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. PMID:26132837

  1. 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. PMID:23178236

  2. PDV modifications.

    SciTech Connect

    Dolan, Daniel H., III

    2010-09-01

    External modifications can transform a conventional photonic doppler velocimetry (PDV) system to other useful configurations - Non-standard probes and Frequency-conversion measurements. This approach is easier than supporting every conceivable measurement in the core PDV design. Circulator specifications may be important - -30 dB isolation (common) probably not be enough, -50 dB isolation is available, and some bench testing may be needed.

  3. THE ROLE OF EPITHELIUM IN EXPERIMENTAL IMMUNIZATION.

    PubMed

    Sewall, H

    1925-10-01

    When a small amount of blood serum is dropped into the nose of a guinea pig the serum is absorbed by the mucous membrane and, after a definite period of incubation, the animal can be shown to have become profoundly changed. Depending upon the number of instillations, the interval between them and, especially, the quantity of serum instilled, the animal becomes either highly hypersensitive or strongly resistant to a toxic injection given by the vein. This resistance withstands a considerable series of increasing toxic injections and is strengthened with lapse of time,-contrary to the state of tolerance produced by traumatic methods. It is inferred that the absorption of foreign protein by the nose causes the formation of two different antibodies. One of these is allergic and excites to anaphylaxis; the other is protective and leads to true immuuity. The relative amount of either antibody can be regulated by modifying the amount of serum instilled. Added to a state of general allergy it is easy to produce, in the guinea pig, a special sensitization of the respiratory apparatus which leads, under appropriate stimulation, to attacks resembling those of bronchial asthma in man. No conclusion can be drawn at present concerning the nature or mode of action of the protective or immunizing antibody; but the indications are that its relations to the circulation and to tissue fixation resemble those which have been developed by other investigators in regard to the anaphylactic antibody. Evidence has been submitted that the living epithelium mediates between foreign protein and the organism in a way to favor specifically the elaboration of true immunity. PMID:17748743

  4. The role of the epithelium in airway remodeling in asthma.

    PubMed

    Davies, Donna E

    2009-12-01

    The bronchial epithelium is the barrier to the external environment and plays a vital role in protection of the internal milieu of the lung. It functions within the epithelial-mesenchymal trophic unit to control the local microenvironment and help maintain tissue homeostasis. However, in asthma, chronic perturbation of these homeostatic mechanisms leads to alterations in the structure of the airways, termed remodeling. Damage to the epithelium is now recognized to play a key role in driving airway remodeling. We have postulated that epithelial susceptibility to environmental stress and injury together with impaired repair responses results in generation of signals that act on the underlying mesenchyme to propagate and amplify inflammatory and remodeling responses in the submucosa. Many types of challenges to the epithelium, including pathogens, allergens, environmental pollutants, cigarette smoke, and even mechanical forces, can elicit production of mediators by the epithelium, which can be translated into remodeling responses by the mesenchyme. Several important mediators of remodeling have been identified, most notably transforming growth factor-beta, which is released from damaged/repairing epithelium or in response to inflammatory mediators, such as IL-13. The cross talk between the epithelium and the underlying mesenchyme to drive remodeling responses is considered in the context of subepithelial fibrosis and potential pathogenetic mechanisms linked to the asthma susceptibility gene, a disintegrin and metalloprotease (ADAM)33. PMID:20008875

  5. Characterization of side population cells from human airway epithelium.

    PubMed

    Hackett, Tillie-Louise; Shaheen, Furquan; Johnson, Andrew; Wadsworth, Samuel; Pechkovsky, Dmitri V; Jacoby, David B; Kicic, Anthony; Stick, Stephen M; Knight, Darryl A

    2008-10-01

    The airway epithelium is the first line of contact with the inhaled external environment and is continuously exposed to and injured by pollutants, allergens, and viruses. However, little is known about epithelial repair and in particular the identity and role of tissue resident stem/progenitor cells that may contribute to epithelial regeneration. The aims of the present study were to identify, isolate, and characterize side population (SP) cells in human tracheobronchial epithelium. Epithelial cells were obtained from seven nontransplantable healthy lungs and four asthmatic lungs by pronase digestion. SP cells were identified by verapamil-sensitive efflux of the DNA-binding dye Hoechst 33342. Using flow cytometry, CD45(-) SP, CD45(+) SP, and non-SP cells were isolated and sorted. CD45(-) SP cells made up 0.12% +/- 0.01% of the total epithelial cell population in normal airway but 4.1% +/- 0.06% of the epithelium in asthmatic airways. All CD45(-) SP cells showed positive staining for epithelial-specific markers cytokeratin-5, E-cadherin, ZO-1, and p63. CD45(-) SP cells exhibited stable telomere length and increased colony-forming and proliferative potential, undergoing population expansion for at least 16 consecutive passages. In contrast with non-SP cells, fewer than 100 CD45(-) SP cells were able to generate a multilayered and differentiated epithelium in air-liquid interface culture. SP cells are present in human tracheobronchial epithelium, exhibit both short- and long-term proliferative potential, and are capable of generation of differentiated epithelium in vitro. The number of SP cells is significantly greater in asthmatic airways, providing evidence of dysregulated resident SP cells in the asthmatic epithelium. Disclosure of potential conflicts of interest is found at the end of this article. PMID:18653771

  6. Defence mechanisms of olfactory neuro-epithelium: mucosa regeneration, metabolising enzymes and transporters.

    PubMed

    Watelet, J B; Strolin-Benedetti, M; Whomsley, R

    2009-01-01

    The olfactory neuro-epithelium is highly sensitive to chemicals and its direct microbiological environment. It also plays a role as an interface between the airways and the nervous system, and so it has developed several defence instruments for rapid regeneration or for the detoxification of the immediate environment. This review illustrates three of these defence mechanisms: regeneration of the epithelium, local production of metabolising enzymes and xenobiotic transporters. Toxicants can inflict damage by a direct toxic response. Alternatively, they may require metabolic activation to produce the proximate toxicant. In addition to detoxifying inhaled and systemically derived xenobiotics, the local olfactory metabolism may fulfil multiple functions such as the modification of inhaled odorant, the modulation of endogenous signalling molecules and the protection of other tissues such as the CNS and lungs from inhaled toxicants. Finally, the permeability of nasal and olfactory mucosa is an important efficacy parameter for some anti-allergic drugs delivered by intranasal administration or inhalation. Efflux or update transporters expressed in these tissues may therefore significantly influence the pharmacokinetics of drugs administered topically. PMID:20084803

  7. Olfactory Epithelium Grafts in the Cerebral Cortex: An Immunohistochemical Analysis

    PubMed Central

    Holbrook, Eric H.; DiNardo, Laurence J.; Costanzo, Richard M.

    2009-01-01

    Objective To develop an alternative model for studying the regenerative capacity of olfactory neurons. Study Design An immunohistochemical analysis of mouse olfactory epithelium transplanted to the cerebral cortex. Methods Strips of olfactory epithelium removed from donor mice at postnatal day 5 to day 20 were inserted into the parietal cortex of adult mice. Recipient animals were allowed to survive for 25 to 120 days and then perfused with 4% paraformaldehyde 1 hour after bromodeoxyuridine injection. The brains were processed, and frozen sections were obtained. Sections through transplant tissue were analyzed using immunohistochemistry and compared with normal olfactory epithelium. Results Graft survival approached 85% with mature olfactory neurons detected in 35% of the transplants stained for olfactory marker protein. Transplant epithelium resembled normal olfactory epithelium containing mature olfactory neurons and axon bundles. Conclusions Studies of olfactory neuron regeneration have been limited by the inability to produce cultures with long-term viability. Olfactory epithelial grafts to the cerebral cortex provide an alternative approach to the study of olfactory neuron regeneration. PMID:11801979

  8. Meckel's diverticulum and ectopic epithelium: Evaluation of a complex relationship

    PubMed Central

    Burjonrappa, Sathyaprasad; Khaing, Phue

    2014-01-01

    Introduction: Meckel's diverticulum is the most common congenital anomaly of the gastrointestinal tract. Currently, for any incidentally discovered Meckel's diverticulum, the management approach is based on weighing the statistical odds of future complications against the risks of a diverticulectomy. Materials and Methods: The temporal relationship between age at Meckel's diverticulectomy and the presence of ectopic epithelium was evaluated in our series. A meta-analysis of all reported recent literature on this condition was subsequently performed to evaluate the strength of the relationship between ectopic epithelium and symptomatic Meckel's diverticulum. Results: There was a paucity of ectopic epithelium in Meckel's diverticulectomy specimens in infants operated on at less than 1 year of age. Having two or more ectopic epithelia in a diverticulum does not appear to carry an additive risk for complications. The meta-analysis confirmed that ectopic epithelium was the most significant factor that influenced surgical intervention in all series of Meckel's diverticulum. Conclusion: The relationship between ectopic epithelium and the development of symptomatic Meckel's diverticulum is complex. Further understanding of the development of ectopic rests in the diverticulum will facilitate elucidating the pathophysiology in symptomatic cases. PMID:24741211

  9. Histopathological study on changes of bronchial epithelium among chromate workers

    SciTech Connect

    Mikami, H.

    1982-09-01

    There have been many reports on lung cancer among chromate workers. Chromate compounds are thought to be a carcinogen and lung cancer among chromate workers is considered one of the occupational lung cancers. Recently, it is debated that metaplastic and hyperplastic changes of bronchial epithelium are revealed or not to the development of bronchogenic carcinoma. Histopathological study on changes of bronchial epithelium among chromate workers was performed in order to clarify the effect of chromate compounds to bronchial epithelium. The subjects were 14 cases of lung cancer among chromate workers. As a control, 18 cases of non cancer among chromate workers. Lung tissue which was obtained at necropsy or surgery was fixed by formalin and was produced cross-sections and was stained on Haematoxylin-Eosin. The results were as follows. 1. Of examined 235 cross-sections, basal cell hyperplasia of bronchial epithelium was found in 13 per cent. Squamous metaplasia was found in 29 per cent, on the contrary, atypical metaplastic changes were observed in 34 per cent. 2. Of four cases of carcinoma in situ and two cases of small invasive carcinoma, four cases revealed development from atypical squamous metaplasia to precancerous changes. 3. These cases developed invasive carcinoma from atypical squamous metaplasia for a long period, of which were found by successive exfoliative cytology of sputum. From these findings, it was concluded that inhalation of chromate dust affected bronchial epithelium and caused highly atypical squamous metaplasia which developed to carcinoma in situ and finally to invasive carcinoma.

  10. Correction of F508del CFTR in airway epithelium using nanoparticles delivering triplex-forming PNAs

    PubMed Central

    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.

    2015-01-01

    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 PNA molecules 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 application of nanoparticles in CF mice produces changes in nasal epithelium potential differences consistent with corrected CFTR, with gene correction also detected in 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. PMID:25914116

  11. Properties of odour-binding glycoproteins from rat olfactory epithelium.

    PubMed

    Fesenko, E E; Novoselov, V I; Bystrova, M F

    1988-01-22

    The specific membrane glycoproteins with high affinity for camphor and decanal were isolated from rat olfactory epithelium. Antibodies to these glycoproteins inhibited both the electroolfactogram and the binding of odorants. The enzyme immunoassay has shown these glycoproteins to be present in the olfactory epithelium of rat, mouse, guinea-pig and hamster but not in that of frog and carp. The molecular mass of the odour-binding glycoproteins from rat olfactory epithelium solubilized by Triton X-100 was approx. 140 kDa. They consisted of two subunits (88 and 55 kDa). The 88 kDa subunit was capable of binding odorants. The data obtained suggest that the glycoproteins isolated have some properties that make them plausible candidates for olfactory receptor molecules. PMID:3337807

  12. In vivo survival and stratification of cultured limbal epithelium.

    PubMed

    Fatima, Anees; Vemuganti, Geeta K; Iftekhar, Ghazala; Rao, Gullapalli N; Sangwan, Virender S

    2007-01-01

    A 6-year-old Bangladeshi girl presented with total limbal stem cell deficiency in the left eye, secondary to a 6-month-old chemical injury. The patient had also previously undergone two limbal transplantation surgeries. At the authors' centre the child underwent autologous cultured limbal epithelium transplantation, on human amniotic membrane, without the use of air-lift technique. Symptomatic relief, re-epithelialization of the ocular surface, regression of corneal pannus and slight improvement in vision were all noted. The corneal button obtained at the time of keratoplasty (performed 4 months later) revealed stratified epithelium with basement membrane. Thirty-seven months post keratoplasty, the best-corrected visual acuity was 6/15 with clear graft and stable ocular surface. Herein, a case of limbal stem cell deficiency successfully managed by monolayer of cultured limbal epithelium is presented. PMID:17300583

  13. Glutathione S-transferases in rat olfactory epithelium: purification, molecular properties and odorant biotransformation.

    PubMed Central

    Ben-Arie, N; Khen, M; Lancet, D

    1993-01-01

    The olfactory epithelium is exposed to a variety of xenobiotic chemicals, including odorants and airborne toxic compounds. Recently, two novel, highly abundant, olfactory-specific biotransformation enzymes have been identified: cytochrome P-450olf1 and olfactory UDP-glucuronosyltransferase (UGT(olf)). The latter is a phase II biotransformation enzyme which catalyses the glucuronidation of alcohols, thiols, amines and carboxylic acids. Such covalent modification, which markedly affects lipid solubility and agonist potency, may be particularly important in the rapid termination of odorant signals. We report here the identification and characterization of a second olfactory phase II biotransformation enzyme, a glutathione S-transferase (GST). The olfactory epithelial cytosol shows the highest GST activity among the extrahepatic tissues examined. Significantly, olfactory epithelium had an activity 4-7 times higher than in other airway tissues, suggesting a role for this enzyme in chemoreception. The olfactory GST has been affinity-purified to homogeneity, and shown by h.p.l.c. and N-terminal amino acid sequencing to constitute mainly the Yb1 and Yb2 subunits, different from most other tissues that have mixtures of more enzyme classes. The identity of the olfactory enzymes was confirmed by PCR cloning and restriction enzyme analysis. Most importantly, the olfactory GSTs were found to catalyse glutathione conjugation of several odorant classes, including many unsaturated aldehydes and ketones, as well as epoxides. Together with UGT(olf), olfactory GST provides the necessary broad coverage of covalent modification capacity, which may be crucial for the acuity of the olfactory process. Images Figure 1 Figure 4 Figure 5 PMID:8503873

  14. Abnormal Ion Permeation through Cystic Fibrosis Respiratory Epithelium

    NASA Astrophysics Data System (ADS)

    Knowles, M. R.; Stutts, M. J.; Spock, A.; Fischer, N.; Gatzy, J. T.; Boucher, R. C.

    1983-09-01

    The epithelium of nasal tissue excised from subjects with cystic fibrosis exhibited higher voltage and lower conductance than tissue from control subjects. Basal sodium ion absorption by cystic fibrosis and normal nasal epithelia equaled the short-circuit current and was amiloride-sensitive. Amiloride induced chloride ion secretion in normal but not cystic fibrosis tissue and consequently was more effective in inhibiting the short-circuit current in cystic fibrosis epithelia. Chloride ion-free solution induced a smaller hyperpolarization of cystic fibrosis tissue. The increased voltage and amiloride efficacy in cystic fibrosis reflect absorption of sodium ions across an epithelium that is relatively impermeable to chloride ions.

  15. 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.

  16. 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...

  17. 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.

  18. Coelomic epithelium-derived cells in visceral morphogenesis.

    PubMed

    Ariza, Laura; Carmona, Rita; Cañete, Ana; Cano, Elena; Muñoz-Chápuli, Ramón

    2016-03-01

    Coelomic cavities of vertebrates are lined by a mesothelium which develops from the lateral plate mesoderm. During development, the coelomic epithelium is a highly active cell layer, which locally is able to supply mesenchymal cells that contribute to the mesodermal elements of many organs and provide signals which are necessary for their development. The relevance of this process of mesenchymal cell supply to the developing organs is becoming clearer because genetic lineage tracing techniques have been developed in recent years. Body wall, heart, liver, lungs, gonads, and gastrointestinal tract are populated by cells derived from the coelomic epithelium which contribute to their connective and vascular tissues, and sometimes to specialized cell types such as the stellate cells of the liver, the Cajal interstitial cells of the gut or the Sertoli cells of the testicle. In this review we collect information about the contribution of coelomic epithelium derived cells to visceral development, their developmental fates and signaling functions. The common features displayed by all these processes suggest that the epithelial-mesenchymal transition of the embryonic coelomic epithelium is an underestimated but key event of vertebrate development, and probably it is shared by all the coelomate metazoans. PMID:26638186

  19. [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

  20. Responses of the rat olfactory epithelium to retronasal air flow.

    PubMed

    Scott, John W; Acevedo, Humberto P; Sherrill, Lisa; Phan, Maggie

    2007-03-01

    Responses of the rat olfactory epithelium were assessed with the electroolfactogram while odorants were presented to the external nares with an artificial sniff or to the internal nares by positive pressure. A series of seven odorants that varied from very polar, hydrophilic odorants to very nonpolar, hydrophobic odorants were used. Although the polar odorants activated the dorsal olfactory epithelium when presented by the external nares (orthonasal presentation), they were not effective when forced through the nasal cavity from the internal nares (retronasal presentation). However, the nonpolar odorants were effective in both stimulus modes. These results were independent of stimulus concentration or of humidity of the carrier air. Similar results were obtained with multiunit recordings from olfactory bulb. These results help to explain why human investigations often report differences in the sensation or ability to discriminate odorants presented orthonasally versus retronasally. The results also strongly support the importance of odorant sorption in normal olfactory processes. PMID:17215498

  1. Odorant-evoked potassium changes in the frog olfactory epithelium.

    PubMed

    Khayari, A; Math, F; Trotier, D

    1991-01-18

    Electroolfactogram (EOG) and extracellular potassium activity (aK) measurements were carried out in frog olfactory epithelia in vivo. Odorant-evoked changes in aK were characterized on the basis of depth profile analysis. Following an olfactory stimulation with butanol vapours, an increase in aK was measured in the mucus and the proximal part of the epithelium; this response started after the beginning of the EOG and was proportional to the amplitude of the latter. In the deeper part of the epithelium, the aK response had complex waveforms showing an initial K decrease which was suppressed by local application of ouabain, suggesting the existence of a pumping mechanism at this level. The results are discussed in terms of extracellular accumulation of K ions following neuroreceptor activation with respect to EOG generation theories. PMID:2015495

  2. Responses of the Rat Olfactory Epithelium to Retronasal Air Flow

    PubMed Central

    Scott, John W.; Acevedo, Humberto P.; Sherrill, Lisa; Phan, Maggie

    2008-01-01

    Responses of the rat olfactory epithelium were assessed with the electroolfactogram while odorants were presented to the external nares with an artificial sniff or to the internal nares by positive pressure. A series of seven odorants that varied from very polar, hydrophilic odorants to very non-polar, hydrophobic odorants were used. While the polar odorants activated the dorsal olfactory epithelium when presented by the external nares (orthonasal presentation), they were not effective when forced through the nasal cavity from the internal nares (retronasal presentation). However, the non-polar odorants were effective in both stimulus modes. These results were independent of stimulus concentration or of humidity of the carrier air. Similar results were obtained with multiunit recording from olfactory bulb. These results help to explain why human investigations often report differences in the sensation or ability to discriminate odorants presented orthonasally vs. retronasally. The results also strongly support the importance of odorant sorption in normal olfactory processes. PMID:17215498

  3. 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.

  4. Morphological study of fetal nasopharyngeal epithelium in man.

    PubMed

    Gulisano, M; Montella, A; Orlandini, S Z; Pacini, P

    1992-01-01

    In 30 human fetuses between 8 and 13 weeks of intrauterine life the lateral wall of the nasopharynx was examined by light microscopy and transmission and scanning electron microscopy. In the subjects between 8 and 9 weeks in utero the mucosa displays still an immature appearance, being mono- or bistratified and lacking the characteristic structures of the respiratory epithelium. Nevertheless, signs of differentiation are to be noticed, with the presence of two distinct cellular types that, in the later periods, will give rise to ciliated cells and microvillus-provided cells. An almost complete differentiation will be reached at 12-13 weeks in utero, even if goblet cells are still lacking in the examined zone during the considered period. Nonrespiratory types of epithelium, such as transitional or squamous, were never found in the studied subjects. PMID:1514372

  5. Nested expression domains for odorant receptors in zebrafish olfactory epithelium.

    PubMed

    Weth, F; Nadler, W; Korsching, S

    1996-11-12

    The mapping of high-dimensional olfactory stimuli onto the two-dimensional surface of the nasal sensory epithelium constitutes the first step in the neuronal encoding of olfactory input. We have used zebrafish as a model system to analyze the spatial distribution of odorant receptor molecules in the olfactory epithelium by quantitative in situ hybridization. To this end, we have cloned 10 very divergent zebrafish odorant receptor molecules by PCR. Individual genes are expressed in sparse olfactory receptor neurons. Analysis of the position of labeled cells in a simplified coordinate system revealed three concentric, albeit overlapping, expression domains for the four odorant receptors analyzed in detail. Such regionalized expression should result in a corresponding segregation of functional response properties. This might represent the first step of spatial encoding of olfactory input or be essential for the development of the olfactory system. PMID:8917589

  6. Liquid Movement Across the Surface Epithelium of Large Airways

    PubMed Central

    Chambers, Lucy A.; Rollins, Brett M.; Tarran, Robert

    2009-01-01

    The cystic fibrosis conductance regulator CFTR gene is found on chromosome 7 (Kerem et al., 1989; Riordan et al., 1989) and encodes for a 1,480 amino acid protein which is present in the plasma membrane of epithelial cells (Anderson et al., 1992). This protein appears to have many functions, but a unifying theme is that it acts as a protein kinase C- and cyclic AMP-regulated Cl- channel (Winpenny et al., 1995; Jia et al., 1997). In the superficial epithelium of the conducting airways, CFTR is involved in Cl- secretion (Boucher, 2003) and also acts as a regulator of the epithelial Na+ channel (ENaC) and hence Na+ absorption (Boucher et al., 1986; Stutts et al., 1995). In this chapter, we will discuss the regulation of these two ion channels, and how they can influence liquid movement across the superficial airway epithelium. PMID:17692578

  7. Cell proliferation in the human gallbladder epithelium: effect of distension.

    PubMed Central

    Putz, P; Willems, G

    1979-01-01

    DNA synthesis activity in the epithelium of the human gallbladder was studied through in vitro labelling of mucosal specimens with 3H-thymidine and autoradiography. The specimens were taken at the time of a surgical operation. Eight 'normal' gallbladders and six distended gallbladders from patients with carcinomatous obstruction of the common bile duct were examined. Proliferative activity was very low in the normal and significantly higher in the distended gallbladders. Images Figure PMID:437558

  8. 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

  9. Primary adenocarcinoma of pigmented ciliary epithelium in a phthisical eye.

    PubMed

    Kumar, Jaya B; Proia, Alan D; Mruthyunjaya, Prithvi; Sharma, Sumit

    2016-01-01

    We report a case of adenocarcinoma of the pigmented ciliary epithelium arising in a phthisical eye. A 92-year-old man who initially presented with severe ocular pain had calcification extending from the posterior pole to ciliary body on B-scan ultrasonography to a degree not previously reported. We highlight the importance of screening for intraocular neoplasms in adults with a long-standing phthisical eye. PMID:26597037

  10. Candida albicans Ultrastructure: Colonization and Invasion of Oral Epithelium

    PubMed Central

    Howlett, Julie A.; Squier, Christopher A.

    1980-01-01

    The colonization and invasion of various animal oral mucosae by Candida albicans were examined in an organ culture model. Scanning and transmission electron microscopy of the oral epithelium between 12 and 30 h after inoculation with the fungus revealed the morphological relationships between host and parasite. Examination of the fungi in thin sections showed five distinct layers in the cell wall of C. albicans within the epithelium, but changes were evident in the organization and definition of the outer cell wall layers in budding hyphae and in hyphae participating in colonization and invasion of the epithelial cells. Adherence of the fungus to the superficial cells of the oral mucosa appeared to involve intimate contact between the epithelial cell surface and the deeper layers of the fungal cell wall. During invasion a close seal was maintained between the invading hyphae and the surrounding epithelial cell envelope, there being no other evidence of damage to the host cell surface except at the site of entry. Within the epithelial cells there was only occasional loss of cytoplasmic components in the vicinity of the invading hyphae. These findings would suggest that enzymatic lysis associated with the invasive process is localized and that the mechanical support provided by surface adherence and the intimate association between the fungus and the epithelial cell envelope may permit growth of Candida on through the epithelium. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:6995338

  11. 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.

  12. Expression of cytokeratins in the epithelium of canine odontogenic tumours.

    PubMed

    Arzi, B; Murphy, B; Nemec, A; Vapniarsky, N; Naydan, D K; Verstraete, F J M

    2011-11-01

    Odontogenic tumours are considered to be relatively rare; however, several histologically distinct types have been identified in dogs. The more common canine odontogenic tumours are peripheral odontogenic fibroma and canine acanthomatous ameloblastoma. The expression of cytokeratins (CKs) has been established for the human dental germ and odontogenic tumours. The aim of the present study was to describe the immunohistochemical expression of a panel of CKs in the epithelium of the canine dental germ, normal gingiva and odontogenic tumours arising in this species. Samples from 20 odontogenic tumours, 12 tooth germs and three normal gingival tissues were obtained. Each sample was stained with haematoxylin and eosin and subjected to immunohistochemistry for CK expression. The typical expression pattern of CKs in the odontogenic epithelium and gingiva of dogs was CK14 and CK5/6. CKs 7, 8, 18 and 20 were generally absent from the canine dental germ, gingiva and odontogenic tumours. Dogs and man therefore exhibit similar CK expression in the odontogenic epithelium. PMID:21511272

  13. Biomechanics of liquid-epithelium interactions in pulmonary airways.

    PubMed

    Ghadiali, Samir N; Gaver, Donald P

    2008-11-30

    The delicate structure of the lung epithelium makes it susceptible to surface tension induced injury. For example, the cyclic reopening of collapsed and/or fluid-filled airways during the ventilation of injured lungs generates hydrodynamic forces that further damage the epithelium and exacerbate lung injury. The interactions responsible for epithelial injury during airway reopening are fundamentally multiscale, since air-liquid interfacial dynamics affect global lung mechanics, while surface tension forces operate at the molecular and cellular scales. This article will review the current state-of-knowledge regarding the effect of surface tension forces on (a) the mechanics of airway reopening and (b) epithelial cell injury. Due to the complex nature of the liquid-epithelium system, a combination of computational and experimental techniques are being used to elucidate the mechanisms of surface-tension induced lung injury. Continued research is leading to an integrated understanding of the biomechanical and biological interactions responsible for cellular injury during airway reopening. This information may lead to novel therapies that minimize ventilation induced lung injury. PMID:18511356

  14. Pathohistological changes of tracheal epithelium in laryngectomized patients.

    PubMed

    Rosso, Marinela; Prgomet, Drago; Marjanović, Ksenija; Pušeljić, Silvija; Kraljik, Nikola

    2015-11-01

    Total laryngectomy results in a permanent disconnection of the upper and lower airways. Thus, the upper airways are bypassed and can no longer condition, humidify, and filter the inhaled air, leading to damage of the tracheobronchial epithelium. There is little scientific information available about the effects of tracheostoma breathing and the degree of mucosal damage in laryngectomized patients. The aims of this study were to determine the histopathologic findings and investigate the potential impact of using a heat and moisture exchanger (HME) on the tracheal epithelium in long-term tracheostomy patients. Tracheal mucosal biopsies were taken from a total of 70 patients. Specimens were stained with hematoxylin and eosin and examined by a light microscope. Normal pseudostratified ciliated columnar epithelium was found in only 9 (12.9%) cases; while, 17 (24.3%) cases had some degree of basal cell hyperplasia. Squamous metaplasia was the most common finding (50%). Pre-invasive lesions (mild and moderate squamous dysplasia) were found in only one patient who used an HME, and in eight (11.4%) non-users. Although the HME cannot completely restore the physiological functions of the upper respiratory track, it delivers a better quality of air to the lower airways and has a positive effect on tracheal mucosa. PMID:25399353

  15. Regeneration of tracheal epithelium using mouse induced pluripotent stem cells.

    PubMed

    Ikeda, Masakazu; Imaizumi, Mitsuyoshi; Yoshie, Susumu; Otsuki, Koshi; Miyake, Masao; Hazama, Akihiro; Wada, Ikuo; Omori, Koichi

    2016-04-01

    Conclusion The findings demonstrated the potential use of induced pluripotent stem cells for regeneration of tracheal epithelium. Objective Autologous tissue implantation techniques using skin or cartilage are often applied in cases of tracheal defects with laryngeal inflammatory lesions and malignant tumor invasion. However, these techniques are invasive with an unstable clinical outcome. The purpose of this study was to investigate regeneration in a tracheal defect site of nude rats after implantation of ciliated epithelium that was differentiated from induced pluripotent stem cells. Method Embryoid bodies were formed from mouse induced pluripotent stem cells. They were cultured with growth factors for 5 days, and then cultured at the air-liquid interface. The degree of differentiation achieved prior to implantation was determined by histological findings and the results of real-time polymerase chain reaction. Embryoid bodies including ciliated epithelium were embedded into collagen gel that served as an artificial scaffold, and then implanted into nude rats, creating an 'air-liquid interface model'. Histological evaluation was performed 7 days after implantation. Results The ciliated epithelial structure survived on the lumen side of regenerated tissue. It was demonstrated histologically that the structure was composed of ciliated epithelial cells. PMID:26755348

  16. Cultured lung epithelium: A cellular model for lung preservation.

    PubMed

    Lee, C Y; Matsumoto-Pon, J; Widdicombe, J H

    1997-11-01

    Cellular models have helped with the development of conditions needed for hypothermic preservation of kidney, liver, and heart. Recently, highly differentiated cultured lung epithelial cell lines grown with basolateral side feeding technique have become available that can mimic airspace, epithelium, and interstitium of lung parenchyma. Cultured lung epithelium coupled with Ussing's short-circuit current technique was used as a cellular model system for lung preservation. A parametric study was conducted to correlate the effects of luminal fluid composition (University of Wisconsin (UW) solution and phosphate-buffered saline) and storage gas (air vs nitrogen) at 4 degrees C for 24 h on postischemic electrogenic properties (transepithelial ion transport and resistance). The results showed that cells were better preserved with the UW solution on both sides as measured by their transepithelial resistance, an indicator of tight junction integrity (Rte approximately 65% of control values approximately 135 Omega cm2). In addition, they responded better to mediators that stimulate chloride secretion than cells preserved with other conditions. Cells preserved with no additional fluid on the apical side had substantially lowered Rte (<20%) than those preserved with an additional thin layer of fluid ( approximately 35-65%). This cellular model system is a realistic representation of lung epithelium and can provide an accurate assessment of preservation quality through the measurements of tight junction integrity and active ion transport. PMID:9367609

  17. 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

  18. 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

  19. 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

  20. 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.

  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. PMID:26868633

  2. Cell cycle of globose basal cells in rat olfactory epithelium.

    PubMed

    Huard, J M; Schwob, J E

    1995-05-01

    The olfactory epithelium of adult mammals has the unique property of generating olfactory sensory neurons throughout life. Cells of the basal compartment, which include horizontal and globose basal cells, are responsible for the ongoing process of neurogenesis in this system. We report here that the globose basal cells in olfactory epithelium of rats, as in mice, are the predominant type of proliferating cell, and account for 97.6% of the actively dividing cells in the basal compartment of the normal epithelium. Globose basal cells have not been fully characterized in terms of their proliferative properties, and the dynamic aspects of neurogenesis are not well understood. As a consequence, it is uncertain whether cell kinetic properties are under any regulation that could affect the rate of neurogenesis. To address this gap in our knowledge, we have determined the duration of both the synthesis phase (S-phase) and the full cell cycle of globose basal cells in adult rats. The duration of the S-phase was found to be 9 hr in experiments utilizing sequential injections of either IdU followed by BrdU or 3H-thy followed by BrdU. The duration of the cell cycle was determined by varying the time interval between the injections of 3H-thy and BrdU and tracking the set of cells that exit S shortly after the first injection. With this paradigm, the interval required for these cells to traverse G2, M, G1, and a second S-phase, is equivalent to the duration of one mitotic cycle and equals 17 hr. These observations serve as the foundation to assess whether the cell cycle duration is subject to regulation in response to experimental injury, and whether such regulation is partly responsible for changes in the rate of neurogenesis in such settings. PMID:7647371

  3. 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

  4. Microwave effect on camphor binding to rat olfactory epithelium

    SciTech Connect

    Philippova, T.M.; Novoselov, V.I.; Bystrova, M.F.; Alekseev, S.I.

    1988-01-01

    Microwave radiation decreased specific camphor binding to a membrane fraction of rat epithelium but not to a Triton X-100 extract of this fraction. Inhibition of the ligand binding did not depend on the modulation frequency of the microwave field in the region 1-100 Hz and was not a linear function of specific absorption rate (SAR). The decreased ligand binding was due to a shedding or release of the specific camphor-binding protein from the membrane into solution. It is highly probable that several other membrane proteins may be shed into solution during microwave exposure.

  5. Immune defense mechanisms in the Caenorhabditis elegans intestinal epithelium

    PubMed Central

    Pukkila-Worley, Read; Ausubel, Frederick M

    2013-01-01

    Intestinal epithelial cells provide an essential line of defense for Caenorhabditis elegans against ingested pathogens. Because nematodes consume microorganisms as their food source, there has presumably been selection pressure to evolve and maintain immune defense mechanisms within the intestinal epithelium. Here we review recent advances that further define the immune signaling network within these cells and suggest mechanisms used by the nematode to monitor for infection. In reviewing studies of pathogenesis that use this simple model system, we hope to illustrate some of the basic principles of epithelial immunity that may also be of relevance in higher order hosts. PMID:22236697

  6. 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

  7. 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

  8. Responses of the rabbit tracheal epithelium in vitro to H(2)O(2)-induced oxidative stress.

    PubMed

    Baeza-Squiban, A; Delcher, L; Kukreti, R; Joly, A C; Guennou, C; Houcine, O; Marano, F

    2000-04-01

    A model of rabbit tracheal epithelial (RTE) cells in primary culture was used to characterize specific and repair responses of airway epithelial cells to oxidative stress. Two well-known reactive oxygen species (ROS) generating systems were used: H(2)O(2) alone or in combination with Fe(2+) to produce the hydroxyl radical. RTE cells exhibited lipid peroxidation when exposed to H(2)O(2) + Fe(2+). Moreover, catalase (CAT) activity decreased after a 1-hour treatment in 3-day-old cultures but increased in 7-day-old cultures which have higher antioxidant enzyme activities. Superoxide dismutase (SOD) activity was never affected. In addition, RTE cells displayed a repair response leading to squamous metaplasia. H(2)O(2) + Fe(2+) treatment resulted in a time-dependent increase in the steady-state level of c-myc mRNA while c-jun and c-fos were not activated. Moreover, a chronic exposure induced the expression of the squamous phenotype characterized by the expression of the cytokeratin 13 confirmed both at the message and protein levels. RTE cells in primary culture react early to H(2)O(2) + Fe(2+) exposure by an increase in c-myc expression and by modifications in CAT activity. Further, a lipid peroxidation occurs and the tracheal epithelium evolves to squamous metaplasia. PMID:10793294

  9. 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

  10. Acanthamoebae bind to glycolipids of rabbit corneal epithelium.

    PubMed Central

    Panjwani, N; Zhao, Z; Baum, J; Pereira, M; Zaidi, T

    1992-01-01

    By use of a thin-layer chromatogram (TLC) overlay procedure, 35S-labeled acanthamoebae were shown to bind to seven glycolipids of rabbit corneal epithelium. Corneal epithelial cells were grown in culture and were subjected to Folch extraction to isolate a chloroform-rich lower phase containing neutral glycosphingolipids (NGSL) and an aqueous upper phase containing gangliosides, i.e., sialic acid-containing glycolipids. Thin-layer chromatography of the upper phase revealed the presence of 10 ganglioside components. Acanthamoebae were shown to bind to four of these components, referred to as 2, 3, 6, and 7. On TLC plates, ganglioside components 2 and 3 migrated slightly ahead of the glycolipid standard GD1a, component 7 comigrated with standard GM3, and component 6 migrated a little more slowly than GM3. Likewise, of the 10 NGSL known to be present in the lower phase, acanthamoebae bound to components 1, 5, and 6. NGSL components 1, 5, and 6 migrated on TLC plates with relative mobilities similar to those of standards asialo GM1, asialo GM2, and ceramidetrihexoside, respectively. We propose that one or more of the Acanthamoeba-reactive glycolipids of corneal epithelium identified in this study may play a role in the pathogenesis of Acanthamoeba keratitis by mediating the adherence of the parasites to the cornea. Images PMID:1639517

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

    PubMed

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

    2014-02-27

    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 Ca(2+) waves, using the epithelium as the conducting pathway. The intercommunication was immunosuppressive, involving Ca(2+)-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. PMID:24463523

  12. 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.

  13. 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.

  14. Choline transport in the isolated rabbit corneal epithelium

    SciTech Connect

    Faust, R.L.

    1988-01-01

    In the present study, isolated epithelial sheets were obtained by performing two sequential anterior keratectomies, three weeks apart, on rabbit corneas. Light microscopy of the isolated sheets revealed a multilayered epithelium with an intact basal cell layer without contamination from other cell types. The accumulation of ({sup 3}H)choline into the epithelial sheets was studied at substrate concentrations varying from 1 to 100 {mu}Moles with and without the addition of specific metabolic and stereochemical inhibitors. Accumulation of ({sup 3}H)choline into these sheets was saturable. Kinetic analysis, performed by estimation from double-reciprocal plots, revealed a single component system with a K{sub m} of 24.9 {mu}M. The metabolic inhibitors potassium cyanide and ouabain showed no effect on the uptake of ({sup 3}H)choline; however, the stereochemical inhibitor hemicholinium-3 significantly reduced the accumulation of radiolabel at both high and low substrate concentrations. The results suggest a non-energy dependent yet a highly specific transport system for the accumulation of choline into the rabbit epithelium.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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

  20. Cell signaling and ion transport across the fish gill epithelium.

    PubMed

    Evans, David H

    2002-08-01

    A large array of circulating and local signaling agents modulate transport of ions across the gill epithelium of fishes by either affecting transport directly or by altering the size and distribution of transporting cells in the epithelium. In some cases, these transport effects are in addition to cardiovascular effects of the same agents, which may affect the perfusion pathways in the gill vasculature and, in turn, affect epithelial transport indirectly. Prolactin is generally considered to function in freshwater, because it is the only agent that allows survival of some hypophysectomized fish species in freshwater. It appears to function by either reducing branchial permeability, Na,K-activated ATPase activity, or reducing the density of chloride cells. Cortisol was initially considered to produce virtually opposite effects (e.g., stimulation of Na,K-activated ATPase and of chloride cell size and density), but more recent studies have found that this steroid stimulates ionic uptake in freshwater fishes, as well as the activity of H-ATPase, an enzyme thought to be central to ionic uptake. Thus, cortisol may function in both high and low salinities. Growth hormone and insulin-like growth factor appear to act synergistically to affect ion regulation in seawater fishes, stimulating both Na,K-activated ATPase and Na-K-2Cl co-transporter activity, and chloride cell size, independent of their effects on growth. Some of the effects of the GH-IGF axis may be via stimulation of the number of cortisol receptors. Thyroid hormones appear to affect seawater ion regulation indirectly, by stimulating the GH-IGF axis. Natriuretic peptides were initially thought to stimulate gill ionic extrusion, but recent studies have not corroborated this finding, so it appears that the major mode of action of these peptides may be reduction of salt loading by inhibition of oral ingestion and intestinal ionic uptake. Receptors for both arginine vasotocin and angiotensin have been described in

  1. In goldfish the discriminative ability for odours persists after reduction of the olfactory epithelium, and rapidly returns after olfactory nerve axotomy and crossing bulbs.

    PubMed

    Zippel, H P

    2000-09-29

    Goldfish are ideal vertebrates for the study of regeneration within the peripheral and the central olfactory system. The present behavioural investigations studied the effects of bilateral lesions on the animals' ability to qualitatively discriminate two amino acids (10(-6) M) and their performance in two more difficult tasks: (i) rewarded amino acid applied in a lower concentration, and (ii) rewarded stimulus contaminated. A 50 and 85% reduction of the olfactory epithelium resulted in no recordable behavioural deficit. After axotomy of olfactory nerves and lateral olfactory tractotomy, fishes were anosmic for seven to ten days. Following replacement of sensory cells in the epithelium, and after regeneration of olfactory tract fibres a full functional recovery i.e. a highly specific regeneration, was recorded. After three surgical modifications of the olfactory bulbs' position, (i) crossing olfactory tracts and bulbs, (ii) crossing tracts and turning bulbs, and (iii) turning bulbs upside down, a full functional recovery was recorded for amino-acid discrimination in a similar concentration. A permanent, and similar slight deficit was, however, found during application of different concentrations, and of contaminated stimuli when medial lateral halves of the bulb were in 'incorrect' position (i) and (ii), or olfactory bulbs were positioned in the vicinity of the contralateral epithelium (i) and (ii). PMID:11079402

  2. 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

  3. ATP-sensitive K(+) channels in rat colonic epithelium.

    PubMed

    Pouokam, Ervice; Bader, Sandra; Brück, Brigitta; Schmidt, Bärbel; Diener, Martin

    2013-06-01

    ATP-sensitive K(+) (KATP) channels couple the metabolic state of a cell to its electrical activity. They consist of a hetero-octameric complex with pore-forming Kir6.x (Kir6.1, Kir6.2) and regulatory sulfonylurea receptor (SUR) subunits. Functional data indicate that KATP channels contribute to epithelial K(+) currents at colonic epithelia. However, their molecular identity and their properties are largely unknown. Therefore, changes in short-circuit current (I sc) induced by the KATP channel opener pinacidil (5 10(-4) mol l(-1)) were measured in Ussing chambers under control conditions and in the presence of different blockers of KATP channels. The channel subunits expressed by the colonic epithelium were identified by immunohistochemistry and by RT-PCR. The K(+) channel opener, when administered at the serosal side, induced an increase in I sc consistent with the induction of transepithelial Cl(-) secretion after activation of basolateral K(+) channels, whereas mucosal administration of pinacidil resulted in a negative I sc. The increase in I sc evoked by serosal pinacidil was inhibited by serosal administration of glibenclamide (5 10(-4) mol l(-1)) and gliclazide (10(-6) mol l(-1)), but was resistant even against a high concentration (10(-2) mol l(-1)) of tolbutamide. In contrast, none of these inhibitors (administered at the mucosal side) reduced significantly the negative I sc induced by mucosal pinacidil. Instead, pinacidil inhibited Cl(-) currents across apical Cl(-) channels in basolaterally depolarized epithelia indicating that the negative I sc induced by mucosal pinacidil is due to a transient inhibition of Cl(-) secretion. In mRNA prepared from isolated colonic crypts, messenger RNA for both pore-forming subunits, Kir6.1 and Kir6.2, and two regulatory subunits (SUR1 and SUR2B) was found. Expression within the colonic epithelium was confirmed for these subunits by immunohistochemistry. In consequence, KATP channels are present in the basolateral membrane

  4. Retinal pigment epithelium engineering using synthetic biodegradable polymers.

    PubMed

    Lu, L; Yaszemski, M J; Mikos, A G

    2001-12-01

    Retinal pigment epithelium (RPE) plays a key role in the maintenance of the normal functions of the retina, especially photoreceptors. Alteration in RPE structure and function is implicated in a variety of ocular disorders. Tissue engineering strategies using synthetic biodegradable polymers as temporary substrates for RPE cell culture and subsequent transplantation may provide a promising new therapy. In this review article, the manufacture of thin biodegradable poly(DL-lactic-co-glycolic acid) (PLGA) films and their degradation behavior in vitro are discussed. RPE cell proliferation and differentiation on these PLGA films are reviewed. The fabrication of model substrates with desired chemical micropatterns in the micrometer scale is discussed and the effects of surface patterning on RPE morphology and function are assessed. Finally. the preparation of biodegradable micropatterns with adhesive PLGA and non-adhesive poly(ethylene glycol)/PLA domains to modulate RPE cell adhesion is presented. PMID:11700807

  5. Microfold (M) cells: important immunosurveillance posts in the intestinal epithelium

    PubMed Central

    Mabbott, Neil A.; Donaldson, David S.; Ohno, Hiroshi; Williams, Ifor R.; Mahajan, Arvind

    2013-01-01

    SUMMARY The transcytosis of antigens across the gut epithelium by microfold cells (M cells) is important for the induction of efficient immune responses to some mucosal antigens in Peyer’s patches. Recently, substantial progress has been made in our understanding of the factors that influence the development and function of M cells. This review highlights these important advances, with particular emphasis on: the host genes which control the functional maturation of M cells; how this knowledge has led to the rapid advance in our understanding of M-cell biology in the steady-state and during aging; molecules expressed on M cells which appear to be used as “immunosurveillance” receptors to sample pathogenic microorganisms in the gut; how certain pathogens appear to exploit M cells to infect the host; and finally how this knowledge has been used to specifically target antigens to M cells to attempt to improve the efficacy of mucosal vaccines. PMID:23695511

  6. Electroolfactogram (EOG) Recording in the Mouse Main Olfactory Epithelium

    PubMed Central

    Chen, Xuanmao; Xia, Zhengui; Storm, Daniel R.

    2016-01-01

    Olfactory sensory neurons in the main olfactory epithelium (MOE) are responsible for detecting odorants and EOG recording is a reliable approach to analyze the peripheral olfactory function. However, recently we revealed that rodent MOE can also detect the air pressure caused by airflow. The sensation of airflow pressure and odorants may function in synergy to facilitate odorant perception during sniffing. We have reported that the pressure-sensitive response in the MOE can also be assayed by EOG recording. Here we describe procedures for pressure-sensitive as well as odorant-stimulated EOG measurement in the mouse MOE. The major difference between the pressure-sensitive EOG response and the odorant-stimulated response was whether to use pure air puff or use an odorized air puff.

  7. 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.

  8. Intermediate Filaments and Polarization in the Intestinal Epithelium.

    PubMed

    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

  9. 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

  10. Mechanical strain inhibits repair of airway epithelium in vitro.

    PubMed

    Savla, U; Waters, C M

    1998-06-01

    The repair of airway epithelium after injury is crucial in restoring epithelial barrier integrity. Although the airway epithelium is stretched and compressed due to changes in both circumferential and longitudinal dimensions during respiration and may be overdistended during mechanical ventilation, the effect of cyclic strain on the repair of epithelial wounds is unknown. Human and cat airway epithelial cells were cultured on flexible membranes, wounded by scraping with a metal spatula, and subjected to cyclic strain using the Flexercell Strain Unit. Because the radial strain profile in the wells was nonuniform, we compared closure in regions of elongation and compression within the same well. Both cyclic elongation and cyclic compression significantly slowed repair, with compression having the greatest effect. This attenuation was dependent upon the time of relaxation (TR) during the cycle. When wells were stretched at 10 cycles/min (6 s/cycle) with TR = 5 s, wounds closed similarly to wounds in static wells, whereas in wells with TR = 1 s, significant inhibition was observed. As the TR during cycles increased (higher TR), wounds closed faster. We measured the effect of strain at various TRs on cell area and centroid-centroid distance (CD) as a measure of spreading and migration. While cell area and CD in static wells significantly increased over time, the area and CD of cells in the elongated regions did not change. Cells in compressed regions were significantly smaller, with significantly lower CD. Cell area and CD became progressively larger with increasing TR. These results suggest that mechanical strain inhibits epithelial repair. PMID:9609726

  11. Porphyromonas gingivalis invades human pocket epithelium in vitro.

    PubMed

    Sandros, J; Papapanou, P N; Nannmark, U; Dahlén, G

    1994-01-01

    The present study examined the adhesive and invasive potential of Porphyromonas gingivalis interacting with human pocket epithelium in vitro. Pocket epithelial tissue, obtained during periodontal surgery of patients with advanced periodontal disease, generated a stratified epithelium in culture. P. gingivalis strains W50 and FDC 381 (laboratory strains), OMGS 712, 1439, 1738, 1739 and 1743 (clinical isolates) as well as Escherichia coli strain HB101 (non-adhering control) were tested with respect to epithelial adhesion and invasion. Adhesion was quantitated by scintillation spectrometry after incubation of radiolabeled bacteria with epithelial cells. The invasive ability of P. gingivalis was measured by means of an antibiotic protection assay. The epithelial multilayers were infected with the test and control strains and subsequently incubated with an antibiotic mixture (metronidazole 0.1 mg/ml and gentamicin 0.5 mg/ml). The number of internalized bacteria surviving the antibiotic treatment was assessed after plating lyzed epithelial cells on culture media. All tested P. gingivalis strains adhered to and entered pocket epithelial cells. However, considerable variation in their adhesive and invasive potential was observed. E. coli strain HB101 did not adhere or invade. Transmission electron microscopy revealed that internalization of P. gingivalis was preceded by formation of microvilli and coated pits on the epithelial cell surfaces. Intracellular bacteria were most frequently surrounded by endosomal membranes; however, bacteria devoid of such membranes were also seen. Release of outer membrane vesicles (blebs) by internalized P. gingivalis was observed. These results support and extend previous work from this laboratory which demonstrated invasion of a human oral epithelial cell-line (KB) by P. gingivalis. PMID:8113953

  12. 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...

  13. STUDIES OF NORMAL GENE EXPRESSION IN THE RAT NASAL EPITHELIUM USNG CDNA ARRAY TECHNOLOGY

    EPA Science Inventory


    Studies of Normal Gene Expression in the Rat Nasal Epithelium Using cDNA Array

    The nasal epithelium is an important target site for chemically-induced toxicity and carcinogenicity .Gene expression data are being used increasingly for studies of such conditions. In or...

  14. Respiratory epithelium lined cysts presenting in the orbit without associated mucocele formation.

    PubMed

    James, C R; Lyness, R; Wright, J E

    1986-05-01

    Three patients presented with orbital cysts lined with upper respiratory tract epithelium. In each case there was no evidence of an associated mucocele. Two patients had a past history of orbital trauma, and the third had had preceding sinus surgery. It is postulated that these cysts were caused by traumatic herniation of nasal sinus epithelium cells into the orbit. PMID:3964639

  15. 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

  16. 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.

  17. Environmental Modification: A Study

    ERIC Educational Resources Information Center

    Grinnell, Richard M., Jr.; Kyte, Nancy S.

    1975-01-01

    This study shows that environmental modification is a surprisingly intricate technique. This may account for its relatively low use and also for its more frequent use by MSW than non-MSW caseworkers. The findings indicate the need for further research on environmental modification. (Author)

  18. 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

  19. Spatially organized response zones in rat olfactory epithelium.

    PubMed

    Scott, J W; Shannon, D E; Charpentier, J; Davis, L M; Kaplan, C

    1997-04-01

    Electroolfactogram recordings were made with a four-electrode assembly from the olfactory epithelium overlying the endoturbinate bones facing the nasal septum. In this study we tested whether odors of different chemical structures produce maximal responses along longitudinally oriented regions following the olfactory receptor gene expression zones described in the literature. The distribution of responses along the dorsal-to-ventral direction of this epithelium (i.e., across the expression zones) was tested in two types of experiments. In one, four electrodes were fixed along the dorsal-to-ventral axis of one turbinate bone. In the other, four electrodes were placed in corresponding positions on four turbinate bones and moved together up toward the top of the bone. These experiments compared the odorants limonene and alpha-terpinene, which are simple hydrocarbons, with carvone and menthone, which differ from the hydrocarbons by the presence of ketone groups. All responses were standardized to an amyl acetate or ethyl butyrate standard. The responses to limonene and alpha-terpinene were often larger for the ventral electrodes. The responses to carvone and menthone were largest for the dorsal electrodes. Intermediate electrodes gave responses that were intermediate in amplitude for these odors. The possibility that direction of air flow caused the observed response distributions was directly tested in experiments with odor nozzles placed in two positions. The relatively larger dorsal responses to carvone and relatively larger ventral responses to limonene were present despite odor nozzle position. We conclude that the responses to this set of odors vary systematically in a fashion parallel to the four gene expression zones. The odorant property that governs this response distribution may be related to the presence of oxygen-containing functional groups. Certain odors evoked larger responses at the intermediate electrode sites than at other sites. Cineole was the best

  20. Interactions between trophoblast and uterine epithelium: monitoring of adhesive forces.

    PubMed

    Thie, M; Röspel, R; Dettmann, W; Benoit, M; Ludwig, M; Gaub, H E; Denker, H W

    1998-11-01

    At embryo implantation, it is postulated that the initial contact between blastocyst and maternal tissues is by adhesion of the trophoblast to the uterine epithelium. This cell-to-cell interaction is thought to be critical for implantation, although the actual adhesive forces have never been determined. In the present study, the atomic force microscope (AFM) was used to study the adhesion between human uterine epithelial cell lines (HEC-1-A; RL95-2) and human trophoblast-type cells (JAR). Specific interaction forces of these epithelia via their apical cell poles were determined on the basis of approach-and-separation cycles. For this purpose, the AFM tip was functionalized with JAR cells, then brought to the surface of uterine epithelial monolayers and was kept in contact for different periods of time (ms, 1, 10, 20, 40 min). The approach force curves displayed repulsive interactions for both HEC-1-A and RL95-2 cells. However, RL95-2 cells (with a smooth surface structure and a thin glycocalyx) showed lower values of the repulsive regime than HEC-1-A cells (with a rough surface structure and a thick glycocalyx). After having overcome repulsive interactions, the initial contact was followed by adhesive interactions. For contact times of 20 and 40 min, RL95-2 cells, but not HEC-1-A cells, showed specific JAR binding, i.e. the separation force curves displayed repeated rupture events in the range of 1-3 nN with a distance between 7-15 microm and, thereafter, a final rupture event at a distance of up to 45 microm. These features point to the formation of strong cell-to-cell bonds. Collectively, these studies provide the first definition of interaction forces between the trophoblast and the uterine epithelium, and are consistent with the hypothesis that an RL95-2-like architecture of uterine epithelial cells, i.e. an non-polarized phenotype, is essential for apical adhesiveness for the human trophoblast. PMID:9853883

  1. Transmigration of macrophages across the choroid plexus epithelium in response to the feline immunodeficiency virus

    PubMed Central

    Meeker, Rick B.; Bragg, D. C.; Poulton, Winona; Hudson, Lola

    2013-01-01

    Although lentiviruses such as human, feline and simian immunodeficiency viruses (HIV, FIV, SIV) rapidly gain access to cerebrospinal fluid (CSF), the mechanisms that control this entry are not well understood. One possibility is that the virus may be carried into the brain by immune cells that traffic across the blood–CSF barrier in the choroid plexus. Since few studies have directly examined macrophage trafficking across the blood–CSF barrier, we established transwell and explant cultures of feline choroid plexus epithelium and measured trafficking in the presence or absence of FIV. Macrophages in co-culture with the epithelium showed significant proliferation and robust trafficking that was dependent on the presence of epithelium. Macrophage migration to the apical surface of the epithelium was particularly robust in the choroid plexus explants where 3-fold increases were seen over the first 24 h. Addition of FIV to the cultures greatly increased the number of surface macrophages without influencing replication. The epithelium in the transwell cultures was also permissive to PBMC trafficking, which increased from 17 to 26% of total cells after exposure to FIV. Thus, the choroid plexus epithelium supports trafficking of both macrophages and PBMCs. FIV significantly enhanced translocation of macrophages and T cells indicating that the choroid plexus epithelium is likely to be an active site of immune cell trafficking in response to infection. PMID:22281685

  2. Kinetics of Lipofuscin Formation in Aging Retinal Pigment Epithelium Cells

    NASA Astrophysics Data System (ADS)

    Family, Fereydoon; Mazzitello, K. I.; Arizmendi, C. M.; Grossniklaus, Hans E.

    2010-03-01

    Lipofuscin is a deposit that is formed over time by aggregation and clustering of incompletely degraded membrane material in various types of cells. Lipofuscin is made of free-radical-damaged protein and fat and is known to be present in age- related macular dgeneration (AMD), Alzheimer disease, and Parkinson disease. AMD is the leading cause of blindness in adults. The degradation of retinal pigment epithelium cells (RPE) through accumulation of lipsofuscin is considered a significant pathogenic factor in the development of AMD. We will present the results of a study of the kinetics of lipofuscin growth in RPE cells using Kinetic Monte Carlo simulations and scaling theory on a cluster aggregation model. The model captures the essential physics of lipofuscin growth in the cells. A remarkable feature is that small particles may be removed from the cells while the larger ones become fixed and grow by aggregation. We compare our results with the number of lipofuscin granules in eyes with early age-related degeneration.

  3. Pathways of ion movement in the canine tracheal epithelium.

    PubMed

    Welsh, M J; Widdicombe, J H

    1980-09-01

    The pathways of ion movement across canine tracheal epithelium, a Cl-secreting tissue, were examined by three techniques. First, the measurement of simultaneous, unidirectional fluxes of Na or Cl and mannitol, a large hydrophilic molecule that serves as a marker of the paracellular pathway, indicated that a significant fraction of both the Na flux from submucosa to mucosa (J Na sm) and the flux of Cl from mucosa to submucosa (J Cl ms) traverse the cellular pathway. The ratio of the Na-to-Cl diffusion coefficients through the paracellular pathway was 0.23, in contrast to the free solution ratio of 0.63. Second, in voltage-clamp experiments we examined the effect of transepithelial voltage differences on the unidirectional fluxes of Na and Cl. The results agree with the previous findings, suggesting that there are voltage-independent, or transcellular, backfluxes of Na and Cl, and that the relative permeability of Na to Cl through the voltage-dependent (presumably paracellular) pathway was 0.28. Third, measurement of transepithelial diffusion potentials gave a Na-to-Cl permeability ratio of 0.31 +/- 0.02 (mean +/- SE). These results suggest that there are significant transcellular backfluxes of Na and Cl and that the paracellular pathway in the canine trachea is anion selective. An anion-selective pathway would tend to shunt the secreted Cl back through the paracellular pathway, thus minimizing the net ion and fluid movement across the tissue in the open-circuit condition. PMID:7435560

  4. Characterization of nucleoside transport systems in cultured rat epididymal epithelium.

    PubMed

    Leung, G P; Ward, J L; Wong, P Y; Tse, C M

    2001-05-01

    The nucleoside transport systems in cultured epididymal epithelium were characterized and found to be similar between the proximal (caput and corpus) and distal (cauda) regions of the epididymis. Functional studies revealed that 70% of the total nucleoside uptake was Na(+) dependent, while 30% was Na(+) independent. The Na(+)-independent nucleoside transport was mediated by both the equilibrative nitrobenzylthioinosine (NBMPR)-sensitive system (40%) and the NBMPR-insensitive system (60%), which was supported by a biphasic dose response to NBMPR inhibition. The Na(+)-dependent [(3)H]uridine uptake was selectively inhibited 80% by purine nucleosides, indicating that the purine nucleoside-selective N1 system is predominant. Since Na(+)-dependent [(3)H]guanosine uptake was inhibited by thymidine by 20% and Na(+)-dependent [(3)H]thymidine uptake was broadly inhibited by purine and pyrimidine nucleosides, this suggested the presence of the broadly selective N3 system accounting for 20% of Na(+)-dependent nucleoside uptake. Results of RT-PCR confirmed the presence of mRNA for equilibrative nucleoside transporter (ENT) 1, ENT2, and concentrative nucleoside transporter (CNT) 2 and the absence of CNT1. It is suggested that the nucleoside transporters in epididymis may be important for sperm maturation by regulating the extracellular concentration of adenosine in epididymal plasma. PMID:11287319

  5. The intestinal epithelium as guardian of gut barrier integrity.

    PubMed

    Zhang, Kaiyi; Hornef, Mathias W; Dupont, Aline

    2015-11-01

    A single layer of epithelial cells separates the intestinal lumen from the underlying sterile tissue. It is exposed to a multitude of nutrients and a large number of commensal bacteria. Although the presence of commensal bacteria significantly contributes to nutrient digestion, vitamin synthesis and tissue maturation, their high number represents a permanent challenge to the integrity of the epithelial surface keeping the local immune system constantly on alert. In addition, the intestinal mucosa is challenged by a variety of enteropathogenic microorganisms. In both circumstances, the epithelium actively contributes to maintaining host-microbial homeostasis and antimicrobial host defence. It deploys a variety of mechanisms to restrict the presence of commensal bacteria to the intestinal lumen and to prevent translocation of commensal and pathogenic microorganisms to the underlying tissue. Enteropathogenic microorganisms in turn have learnt to evade the host's immune system and circumvent the antimicrobial host response. In the present article, we review recent advances that illustrate the intense and intimate host-microbial interaction at the epithelial level and improve our understanding of the mechanisms that maintain the integrity of the intestinal epithelial barrier. PMID:26294173

  6. [Morphology of the reproductive age women cervical epithelium under hypothyreosis].

    PubMed

    Beruchashvili, M; Gogiashvili, L; Tsagareli, Z; Topuriya, Z

    2013-01-01

    The purpose of the investigation was to examine the morphological manifestations of hypothyreosis in the reproductive age women cervical mucosa. With clinically verified hypothyreosis in 1524 cases, 538 patients had a different variants of endocervical pathology, accounting for two major research groups: I - (n=259) operated by colloidal goiter treated by L-thyroxin during last 3 years, II - (n=279) with similar diagnosis, without replacement therapy within last 3 years. Therapeutic and diagnostic scrapings from cervix, as well as parallel samples of the operative removal thyroid gland (TG), after staining with hematoxylin and eosin and picrofuchsin by van Gieson were studied morphologically. The different variants of the cervical mucosa reaction from simple hyperplasia in treated group to adenomyosis with stratification of epithelium, and the tendency of sclerosis and atrophy in the group not receiving L-thyroxin were revealed. In all compared cases Spearmen correlation coefficient had high level of relevance (0,00003). We believe that the cervix changes are the consequence of the decrease of sensitivity to estrogen under the low level of T3 and T4 and increase TSH in plasma. Molecular atypia of endocervical cells clearly demon-strates cross-combination of two leading hormonal systems. PMID:23388537

  7. Cytokeratin expression and acetowhite change in cervical epithelium.

    PubMed Central

    Maddox, P; Szarewski, A; Dyson, J; Cuzick, J

    1994-01-01

    AIM--To investigate the distribution of cytokeratins 10, 13, 14 and 19 in biopsy specimens taken from acetowhite and non-acetowhite areas of the cervix. METHOD--Cervical biopsy specimens were taken from both acetowhite and non-acetowhite areas from 44 patients who presented with abnormal cervical cytology. The specimens were snap frozen in liquid nitrogen and multiple sections taken from each specimen. Staining was performed for cytokeratins 10, 13, 14, 19 and NADPH diaphorase enzyme. The areas of each section positive for the various markers were measured. RESULTS--Cytokeratin 10 positive cells were greatly increased in number in acetowhite biopsy specimens compared with non-acetowhite samples (45.1% v 2.8%; p < 0.0001). Cytokeratin 19 was also increased, but to a lesser extent (17.8% v 5.5%; p < 0.0001). In contrast, the almost universal expression of cytokeratin 13 was reduced in acetowhite biopsy specimens (86.2% v 96.9%; p < 0.0001). Cytokeratin 14 was found diffusely in the basal region of the stratified squamous epithelium and was marginally more apparent in the acetowhite biopsy specimens (p = 0.04). CONCLUSION--It is suggested that the presence of cytokeratin 10 may be an essential requirement for the formation of acetowhite change in association with the cellular swelling caused by acetic acid. Images PMID:7510721

  8. 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

  9. 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

  10. 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.

  11. Desmosomes in the uterine epithelium of noninvasive skink placentae.

    PubMed

    Biazik, Joanna M; Thompson, Michael B; Murphy, Christopher R

    2010-03-01

    Australian species of viviparous skinks have noninvasive epitheliochorial placentation where there is no breeching or interruption of the uterine epithelial cell barrier. This is contrary to some African and South American species of skinks which exhibit invading chorionic cells and a localized endotheliochorial placenta. The desmosomes, which maintain the adhesive properties of the junctional complex between uterine epithelial cells, were found to decrease as gestation progressed in the uterus of two highly placentotrophic Australian skinks, but no changes in desmosomal numbers were present in the uterus of two Australian oviparous skinks or viviparous skinks with a simple placenta. In mammals, desmosomes decrease in the uterine epithelium of species with invasive hemochorial placentation, where less chemical and mechanical adhesion between cells assists the invading trophoblast at the time of implantation. However, Australian viviparous skinks do not have an invasive trophoblast; yet, similarities in decreasing lateral cellular adhesion exist in the uterus of both invasive and noninvasive placental types. This similarity in cellular mechanisms suggests a conservation of plasma membrane changes across placentation irrespective of reptilian or mammalian origin. PMID:20169564

  12. 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

  13. 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

  14. Surface characteristics of isopod digestive gland epithelium studied by SEM.

    PubMed

    Millaku, Agron; Leser, Vladka; Drobne, Damjana; Godec, Matjaz; Torkar, Matjaz; Jenko, Monika; Milani, Marziale; Tatti, Francesco

    2010-05-01

    The structure of the digestive gland epithelium of a terrestrial isopod Porcellio scaber has been investigated by conventional scanning electron microscopy (SEM), focused ion beam-scanning electron microscopy (FIB/SEM), and light microscopy in order to provide evidence on morphology of the gland epithelial surface in animals from a stock culture. We investigated the shape of cells, extrusion of lipid droplets, shape and distribution of microvilli, and the presence of bacteria on the cell surface. A total of 22 animals were investigated and we found some variability in the appearance of the gland epithelial surface. Seventeen of the animals had dome-shaped digestive gland "normal" epithelial cells, which were densely and homogeneously covered by microvilli and varying proportions of which extruded lipid droplets. On the surface of microvilli we routinely observed sparsely distributed bacteria of different shapes. Five of the 22 animals had "abnormal" epithelial cells with a significantly altered shape. In three of these animals, the cells were much smaller, partly or completely flat or sometimes pyramid-like. A thick layer of bacteria was detected on the microvillous border, and in places, the shape and size of microvilli were altered. In two animals, hypertrophic cells containing large vacuoles were observed indicating a characteristic intracellular infection. The potential of SEM in morphological investigations of epithelial surfaces is discussed. PMID:20155290

  15. Expression of homeobox genes in the mouse olfactory epithelium.

    PubMed

    Parrilla, Marta; Chang, Isabelle; Degl'Innocenti, Andrea; Omura, Masayo

    2016-10-01

    Homeobox genes constitute a large family of genes widely studied because of their role in the establishment of the body pattern. However, they are also involved in many other events during development and adulthood. The main olfactory epithelium (MOE) is an excellent model to study neurogenesis in the adult nervous system. Analyses of homeobox genes during development show that some of these genes are involved in the formation and establishment of cell diversity in the MOE. Moreover, the mechanisms of expression of odorant receptors (ORs) constitute one of the biggest enigmas in the field. Analyses of OR promoters revealed the presence of homeodomain binding sites in their sequences. Here we characterize the expression patterns of a set of 49 homeobox genes in the MOE with in situ hybridization. We found that seven of them (Dlx3, Dlx5, Dlx6, Msx1, Meis1, Isl1, and Pitx1) are zonally expressed. The homeobox gene Emx1 is expressed in three guanylate cyclase(+) populations, two located in the MOE and the third one in an olfactory subsystem known as Grüneberg ganglion located at the entrance of the nasal cavity. The homeobox gene Tshz1 is expressed in a unique patchy pattern across the MOE. Our findings provide new insights to guide functional studies that aim to understand the complexity of transcription factor expression and gene regulation in the MOE. J. Comp. Neurol. 524:2713-2739, 2016. © 2016 Wiley Periodicals, Inc. PMID:27243442

  16. Effect of ammonium on bacterial adherence to bladder transitional epithelium.

    PubMed

    Parsons, C L; Stauffer, C; Mulholland, S G; Griffith, D P

    1984-08-01

    The virulence of urease-producing bacteria depends on the ability of urease to degrade urea into ammonia and thereby to alkalinize the urine. Infections caused by urease-producing organisms such as Proteus mirabilis are particularly difficult to manage clinically. We have shown that the layer of glycosaminoglycans at the bladder surface protects against infection by blocking the adherence of bacteria to the epithelium. To determine whether urease-producing urinary pathogens owe their virulence in part to an ability to inactivate the protective effect of the glycosaminoglycan layer, we tested the ability of ammonium chloride to alter bacterial adherence to the normal vesical mucosa. We used an in vivo adherence assay that we have described previously in rabbits. Control animals received sodium chloride adjusted to the same pH as the ammonium chloride. We found that 0.25 M ammonium chloride significantly increases bacterial adherence to normal vesical mucosa as compared to adherence in controls receiving 0.25 M sodium chloride (p less than 0.05). These data suggest that urease plays a hitherto undescribed role in bacterial virulence by altering the antiadherence activity of the glycosaminoglycan layer present at the transitional cell surface. PMID:6376829

  17. Morphological integrity of the bronchial epithelium in mild asthma.

    PubMed Central

    Lozewicz, S; Wells, C; Gomez, E; Ferguson, H; Richman, P; Devalia, J; Davies, R J

    1990-01-01

    In severe asthma bronchial epithelial cells are damaged and detached, and it has been proposed that such damage might lead to the bronchial hyperresponsiveness that characterises asthma. To investigate the relation between airway hyperresponsiveness and epithelial damage, biopsy specimens of the bronchial mucus membrane were obtained at fibreoptic bronchoscopy from 11 patients with mild atopic asthma and airway hyperresponsiveness (provocative concentration of methacholine causing a 20% fall in FEV1 (PC20) less than 1.0 mg/ml), and from 17 healthy non-atopic subjects who did not have airway hyperresponsiveness (PC20 methacholine greater than 8.0 mg/ml). Observers who were blind to the presence or absence of asthma examined the biopsy specimens by light and electron microscopy. Epithelial cells, intercellular spaces, and goblet cells were counted. Intercellular junctional complexes were examined, and a semiquantitative assessment was made of ciliary loss, non-parallel central ciliary filaments, and vacuoles in ciliated cells. There were no differences between the asthmatic and healthy groups in any of these measurements. These findings indicate that airway hyperresponsiveness may be present when there is no apparent change in the structure of the bronchial epithelium. PMID:2321171

  18. Cellular and shunt conductances of toad bladder epithelium.

    PubMed

    Gordon, L G

    1978-12-29

    Toad urinary bladders were mounted in Ussing-type chambers and volt-age-clamped. At nonzero voltages only, small fluctuations in current, delta I, and therefore in tissue conductance, delta Gt, were detected. These fluctuations were caused by the smooth muscle of the underlying tissue which could be monitored continuously and simultaneously with the current, I. Inhibition of the smooth muscle contraction with verapamil (2 X 10(-5) M) abolished the fluctuations in I and Gt. Amiloride (10(-4) M) had no significant effect on the magnitude of delta Gt, oxytocin increased Gt without affecting delta Gt, and mucosal hypertonicity produced by mannitol increased delta Gt. These results are consistent with the hypothesis that two parallel pathways exist for passive current flow across the toad urinary bladder: one, the cellular pathway, was not affected by smooth muscle activity; the other, the paracellular pathway, was the route whose conductance was altered by the action of the smooth muscle. Thus the relationship between the cellular and shunt conductances of the epithelium of the toad urinary bladder, under a variety of conditions, can be investigated by utilizing the effects of the movement of the smooth muscle. PMID:110941

  19. Electrically assisted delivery of macromolecules into the corneal epithelium

    PubMed Central

    Hao, Jinsong; Li, S. Kevin; Liu, Chia-Yang; Kao, Winston W.Y.

    2009-01-01

    Electrically assisted delivery is noninvasive and has been investigated in a number of ocular drug delivery studies. The objectives of this study were to examine the feasibility of electrically assisted delivery of macromolecules such as small interfering RNA (siRNA) into the corneal epithelium, to optimize the iontophoresis and electroporation methods, and to study the mechanisms of corneal iontophoresis for macromolecules. Anodal and cathodal iontophoresis, electroporation and their combinations were the methods examined with mice in vivo. Cyanine 3 (Cy3) glyceraldehyde 3-phosphate dehydrogenease (GAPDH) siRNA and fluorescein isothiocyanate (FITC)-dextran of different molecular weights (4 to 70 kDa) were the macromolecules studied. Microscopy and histology after cryostat sectioning were used to analyze and compare the delivery of the macromolecules to the cornea. Iontophoresis was effective in delivering siRNA and dextran up to 70 kDa into the cornea. The electroporation method studied was less effective than that of iontophoresis. Although both iontophoresis and electroporation alone can deliver the macromolecules into the cornea, these methods alone were not as effective as the combination of iontophoresis and electroporation (iontophoresis followed by electroporation). The significant enhancement of dextran delivery in anodal iontophoresis suggests that electroosmosis can be a significant flux enhancing mechanism during corneal iontophoresis. These results illustrate the feasibility of electrically assisted delivery of macromolecules such as siRNA into the cornea. PMID:19682448

  20. 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

  1. Identification of transcripts overexpressed during airway epithelium differentiation.

    PubMed

    Chhin, B; Pham, J T; El Zein, L; Kaiser, K; Merrot, O; Bouvagnet, P

    2008-07-01

    Human airway epithelium, the defence at the forefront of protecting the respiratory tract, evacuates inhaled particles by a permanent beating of epithelial cell cilia. When deficient, this organelle causes primary ciliary dyskinesia, and, despite numerous studies, data regarding ciliated cell gene expression remain incomplete. The aim of the present study was to identify genes specifically expressed in human ciliated respiratory cells via transcriptional analysis. The transcriptome of dedifferentiated epithelial cells was subtracted from that of fully redifferentiated cells using complementary DNA representational difference analysis. In order to validate the results, gene overexpression in ciliated cells was confirmed by real-time PCR, and by comparing the present list of genes overexpressed in ciliated cells to lists obtained in previous studies. A total of 53 known and 12 unknown genes overexpressed in ciliated cells were identified. The majority (66%) of known genes had never previously been reported as being involved in ciliogenesis, and the unknown genes represent hypothetical novel transcript isoforms or new genes not yet reported in databases. Finally, several genes identified here were located in genomic regions involved in primary ciliary dyskinesia by linkage analysis. In conclusion, the present study revealed sequences of new cilia-related genes, new transcript isoforms and novel genes which should be further characterised to aid understanding of their function(s) and their probable disorder-related involvement. PMID:18321927

  2. 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

  3. 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. PMID:23948668

  4. 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

  5. Modified Behavior Modification.

    ERIC Educational Resources Information Center

    Vockell, Edward

    1982-01-01

    Argues that major behavior modification techniques can be easily and usefully integrated into a classroom management strategy. Focuses on the need for teachers to consider the internal perceptions of students when employing the techniques. (FL)

  6. Study Faults Behavior Modification

    ERIC Educational Resources Information Center

    Science News, 1977

    1977-01-01

    Reports on the analysis of 27 behavior modification programs for delinquents. Findings reveal that a low percentage of the programs have followup mechanisms and that the behavior which is modified is often not that which caused the problem. (CP)

  7. Enzymatic modification of schizophyllan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An enzymatic method was developed for the progressive modification of the polysaccharide schizophyllan. Fungal strains Hypocrea nigricans NRRL 62555, Penicillium crustosum NRRL 62558, and Penicillium simplicissimum NRRL 62550 were previously identified as novel sources of ß-endoglucanase with specif...

  8. Effects of female sex hormones on adhesion of Candida albicans yeast-like fungi to the buccal epithelium.

    PubMed

    Kravtsov, E G; Anokhina, I V; Rybas, Ya A; Sachivkina, N P; Ermolaev, A V; Brodskaya, S B

    2014-06-01

    Hormonal regulation of receptor expression and glycogen concentrations in the epithelial cells of the oral cavity remains poorly studied. Adhesion of microorganisms to the vaginal epithelium correlates with their adhesion to the buccal epithelium. Analysis of the correlation between Candida adhesion to the vaginal and buccal epithelium depending on the hormonal status has demonstrated that activity of Candida albicans strains in the buccal epithelium correlates with their adhesion activity in the vaginal epithelium, with the coefficient of correlations (r) reaching 0.76. PMID:24958376

  9. Histone Modifications and Cancer.

    PubMed

    Audia, James E; Campbell, Robert M

    2016-01-01

    SUMMARYHistone posttranslational modifications represent a versatile set of epigenetic marks involved not only in dynamic cellular processes, such as transcription and DNA repair, but also in the stable maintenance of repressive chromatin. In this article, we review many of the key and newly identified histone modifications known to be deregulated in cancer and how this impacts function. The latter part of the article addresses the challenges and current status of the epigenetic drug development process as it applies to cancer therapeutics. PMID:27037415

  10. 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

  11. 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)

  12. 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

  13. MORPHOMETRIC ASPECTS OF CILIARY DISTRIBUTION AND CILIOGENESIS IN HUMAN NASAL EPITHELIUM

    EPA Science Inventory

    Observations of freeze-fracture preparations of human nasal epithelium have provided a unique perspective of the spatial distribution of epithelial cell cilia unattainable by more conventional ultrastructural techniques. The initial stages of ciliogenesis were characterized ultra...

  14. 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

  15. 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

  16. 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

  17. 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.

  18. Cigarette Smoke Delays Regeneration of the Olfactory Epithelium in Mice.

    PubMed

    Ueha, Rumi; Ueha, Satoshi; Sakamoto, Takashi; Kanaya, Kaori; Suzukawa, Keigo; Nishijima, Hironobu; Kikuta, Shu; Kondo, Kenji; Matsushima, Kouji; Yamasoba, Tatsuya

    2016-08-01

    The olfactory system is a unique part of the mammalian nervous system due to its capacity for neurogenesis and the replacement of degenerating receptor neurons. Cigarette smoking is a major cause of olfactory dysfunction. However, the mechanisms by which cigarette smoke impairs the regenerative olfactory receptor neurons (ORNs) remain unclear. Here, we investigated the influence of cigarette smoke on ORN regeneration following methimazole-induced ORN injury. Administration of methimazole caused detachment of the olfactory epithelium from the basement membrane and induced olfactory dysfunction, thus enabling us to analyze the process of ORN regeneration. We found that intranasal administration of cigarette smoke solution (CSS) suppressed the recovery of ORNs and olfaction following ORN injury. Defective ORN recovery in CSS-treated mice was not associated with any change in the number of SOX2(+) ORN progenitor cells in the basal layer of the OE, but was associated with impaired recovery of GAP43(+) immature ORNs. In the nasal mucosa, mRNA expression levels of neurotrophic factors such as brain-derived neurotrophic factor, neurotrophin-3, neurotrophin-5, glial cell-derived neurotrophic factor, and insulin-like growth factor-1 (IGF-1) were increased following OE injury, whereas CSS administration decreased the ORN injury-induced IGF-1 expression. Administration of recombinant human IGF-1 prevented the CSS-induced suppression of ORN recovery following injury. These results suggest that CSS impairs regeneration of ORNs by suppressing the development of immature ORNs from ORN progenitors, at least partly by reducing IGF-1 in the nasal mucosa. PMID:27003941

  19. 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

  20. 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

  1. 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. PMID:17656441

  2. 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. PMID:23950179

  3. 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

  4. Homeostatic capabilities of the choroid plexus epithelium in Alzheimer's disease

    PubMed Central

    Johanson, Conrad; McMillan, Paul; Tavares, Rosemarie; Spangenberger, Anthony; Duncan, John; Silverberg, Gerald; Stopa, Edward

    2004-01-01

    As the secretory source of vitamins, peptides and hormones for neurons, the choroid plexus (CP) epithelium critically provides substances for brain homeostasis. This distributive process of cerebrospinal fluid (CSF) volume transmission reaches many cellular targets in the CNS. In ageing and ageing-related dementias, the CP-CSF system is less able to regulate brain interstitial fluid. CP primarily generates CSF bulk flow, and so its malfunctioning exacerbates Alzheimers disease (AD). Considerable attention has been devoted to the blood-brain barrier in AD, but more insight is needed on regulatory systems at the human blood-CSF barrier in order to improve epithelial function in severe disease. Using autopsied CP specimens from AD patients, we immunocytochemically examined expression of heat shock proteins (HSP90 and GRP94), fibroblast growth factor receptors (FGFr) and a fluid-regulatory protein (NaK2Cl cotransporter isoform 1 or NKCC1). CP upregulated HSP90, FGFr and NKCC1, even in end-stage AD. These CP adjustments involve growth factors and neuropeptides that help to buffer perturbations in CNS water balance and metabolism. They shed light on CP-CSF system responses to ventriculomegaly and the altered intracranial pressure that occurs in AD and normal pressure hydrocephalus. The ability of injured CP to express key regulatory proteins even at Braak stage V/VI, points to plasticity and function that may be boosted by drug treatment to expedite CSF dynamics. The enhanced expression of human CP 'homeostatic proteins' in AD dementia is discussed in relation to brain deficits and pharmacology. PMID:15679944

  5. Transcriptional regionalization of the fruit fly's airway epithelium.

    PubMed

    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

  6. Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

    PubMed Central

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

    2013-01-01

    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. PMID:23950179

  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. PMID:26591606

  8. 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

  9. 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

  10. 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. PMID:22084286

  11. 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

  12. Identification of Distinct Layers Within the Stratified Squamous Epithelium of the Adult Human True Vocal Fold

    PubMed Central

    Dowdall, Jayme R.; Sadow, Peter M.; Hartnick, Christopher; Vinarsky, Vladimir; Mou, Hongmei; Zhao, Rui; Song, Phillip C.; Franco, Ramon A.; Rajagopal, Jayaraj

    2016-01-01

    Objectives/Hypothesis A precise molecular schema for classifying the different cell types of the normal human vocal fold epithelium is lacking. We hypothesize that the true vocal fold epithelium has a cellular architecture and organization similar to that of other stratified squamous epithelia including the skin, cornea, oral mucosa, and esophagus. In analogy to disorders of the skin and gastrointestinal tract, a molecular definition of the normal cell types within the human vocal fold epithelium and a description of their geometric relationships should serve as a foundation for characterizing cellular changes associated with metaplasia, dysplasia, and cancer. Study Design Qualitative study with adult human larynges. Methods Histologic sections of normal human laryngeal tissue were analyzed for morphology (hematoxylin and eosin) and immunohistochemical protein expression profile, including cytokeratins (CK13 and CK14), cornified envelope proteins (involucrin), basal cells (NGFR/p75), and proliferation markers (Ki67). Results We demonstrated that three distinct cell strata with unique marker profiles are present within the stratified squamous epithelium of the true vocal fold. We used these definitions to establish that cell proliferation is restricted to certain cell types and layers within the epithelium. These distinct cell types are reproducible across five normal adult larynges. Conclusion We have established that three layers of cells are present within the normal adult stratified squamous epithelium of the true vocal fold. Furthermore, replicating cell populations are largely restricted to the parabasal strata within the epithelium. This delineation of distinct cell populations will facilitate future studies of vocal fold regeneration and cancer. Level of Evidence N/A. PMID:25988619

  13. 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.

  14. 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…

  15. Personalizing Behavior Modification.

    ERIC Educational Resources Information Center

    White, Debra G.; And Others

    1987-01-01

    Process reinforcement is proposed as a reinforcement method that is more comfortable, personal, comprehensive, and interactive than traditional behavior modification. Process reinforcement strengthens desired behaviors by engaging learners in a one-on-one examination of how they achieved correct responses and by practicing comfortable eye contact…

  16. 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…

  17. Instructional Improvement: Behavior Modification.

    ERIC Educational Resources Information Center

    Haring, Norris G.; Hayden, Alice H.

    Sixteen papers are provided. B. F. Skinner discusses the arrangement of contingencies for learning: Lloyd Homme describes behavioral engineering; and Frank Hewett considers behavior modification in special education. Also treated are experimental education by Norris Haring, program evaluation by Arthur Lumsdaine, and administration of special…

  18. Behavior Modification: Education's Watergate.

    ERIC Educational Resources Information Center

    Carrison, Muriel Paskin

    Several of the theoretical and experimental assumptions relating to behavior modification are examined and criticized: (1) the human mind can only be understood by observing and measuring the functional behavior it causes, (2) performance can be equated with learning, (3) reward systems and token economies improve intrinsic learning, and (4) all…

  19. Defining Behavior Modification

    ERIC Educational Resources Information Center

    Christoplos, Florence; Valletutti, Peter

    1969-01-01

    Discusses the proposition that: "The educational problem involved in behavior modification, in the evaluationand measurement of learning, is the integration and coordination of three types of information affecting the achievement of specific behavioral goals: (1) information about the child, (2) information about the task, and (3) information…

  20. 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

  1. 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

  2. Pigment-epithelium-derived factor (PEDF) occurs at a physiologically relevant concentration in human blood: purification and characterization.

    PubMed Central

    Petersen, Steen V; Valnickova, Zuzana; Enghild, Jan J

    2003-01-01

    Pigment epithelium-derived factor (PEDF) inhibits the formation of blood vessels in the eye by inducing apotosis in actively dividing endothelial cells. The activity of PEDF equals or supersedes that of other anti-angiogenic factors, including angiostatin, endostatin and thrombospondin-1. In addition, PEDF has the potential to promote the survival of neurons and affect their differentiation. Here we show that PEDF is present in plasma at a concentration of approx. 100 nM (5 microg/ml) or twice the level required to inhibit aberrant blood-vessel growth in the eye. Thus the systemic delivery of PEDF has the potential to affect angiogenesis or neurotrophic processes throughout the body, significantly expanding the putative physiological role of the protein. A complete map of all post-translational modifications revealed that authentic plasma PEDF carries an N-terminal pyroglutamate blocking group and an N-linked glycan at position Asn266. The pyroglutamate residue may regulate the activity of PEDF analogously to the manner in which it regulates thyrotropin-releasing hormone. PMID:12737624

  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

    2015-01-01

    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. PMID:25914116

  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. 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

  6. Cystic fibrosis growth retardation is not correlated with loss of Cftr in the intestinal epithelium

    PubMed Central

    Grady, Brian R.; Mishra, Kirtishri; Cotton, Calvin U.; Drumm, Mitchell L.

    2011-01-01

    Maldigestion due to exocrine pancreatic insufficiency leads to intestinal malabsorption and consequent malnutrition, a mechanism proposed to cause growth retardation associated with cystic fibrosis (CF). However, although enzyme replacement therapy combined with increased caloric intake improves weight gain, the effect on stature is not significant, suggesting that growth retardation has a more complex etiology. Mouse models of CF support this, since these animals do not experience exocrine pancreatic insufficiency yet are growth impaired. Cftr absence from the intestinal epithelium has been suggested as a primary source of growth retardation in CF mice, a concept we directly tested by generating mouse models with Cftr selectively inactivated or restored in intestinal epithelium. The relationship between growth and functional characteristics of the intestines, including transepithelial electrophysiology, incidence of intestinal obstruction, and histopathology, were assessed. Absence of Cftr exclusively from intestinal epithelium resulted in loss of cAMP-stimulated short-circuit current, goblet cell hyperplasia, and occurrence of intestinal obstructions but only slight and transient impaired growth. In contrast, specifically restoring Cftr to the intestinal epithelium resulted in restoration of ion transport and completely protected against obstruction and histopathological anomalies, but growth was indistinguishable from CF mice. These results indicate that absence of Cftr in the intestinal epithelium is an important contributor to the intestinal obstruction phenotype in CF but does not correlate with the observed growth reduction in CF. PMID:21659619

  7. Content of trans fatty acids in human cheek epithelium: comparison with serum and adipose tissue.

    PubMed

    Abraham, Ransi A; Bahl, Vinay K; Parshad, Rajinder; Seenu, V; Roy, Ambuj; Golandaz, Smita; Dorairaj, Prabhakaran; Ramakrishnan, Lakshmy

    2013-01-01

    Studies pertaining to trans fatty acids (TFA), which have been implicated in development of chronic diseases, are more relevant in developing countries where nutrition transition is changing traditional habits and practices. Measuring TFA is an arduous task because of the need for fat biopsies. This study identifies a tissue, which can be easily accessed for analytical measurement of trans fatty acid. In this cross-sectional study, fatty acid in adipose tissue, cheek epithelium, and blood samples were assessed by gas chromatography. Spearman correlation coefficient was computed to study the correlation of fatty acid distribution among the three tissues. The correlation coefficient of total trans fatty acid between cheek epithelium and serum was 0.30 (P < 0.02) and between cheek epithelium and adipose tissue was 0.33 (P < 0.019). This study is the first to report trans fatty acid profile in cheek epithelium giving scope for utilizing the cheek epithelium as a tissue for objective assessment of trans fatty acid intake. PMID:24222900

  8. 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

  9. Phagocytosis of Giardia muris by macrophages in Peyer's patch epithelium in mice.

    PubMed Central

    Owen, R L; Allen, C L; Stevens, D P

    1981-01-01

    No mechanism for the initiation of immunological clearance of Giardia from the mammalian intestinal tract has been identified. In normal and nude mice experimentally infected with G. muris, we examined antigen-sampling epithelium over Peyer's patch follicles by electron microscopy for evidence of interaction between G. muris and lymphoid cells. Invading G. muris were found in the epithelium near dying or desquamating columnar cells. Macrophages beneath the basal lamina extended pseudopods into the epithelium, trapping invading G. muris and enclosing them in phagolysosomes. In normal mice, which clear G. muris in 4 to 6 weeks, macrophages containing digested G. muris were surrounded by rosettes of lymphoblasts in the epithelium. In nude mice deficient in lymphocytes, there was apparent hyperplasia of macrophages, which filled the follicle domes, resulting in more frequent entrapment of G. muris but no contact between macrophages and lymphoblasts in the epithelium. In nude mice, which require 6 months to control G. muris infection, lymphoblast contact with macrophages containing distinctive microtubular remnants of G. muris was only identified in the follicle dome. This close physical association of lymphoblasts and macrophages containing G. muris remnants suggests that this macrophage activity represents intraepithelial antigen processing as well as a defense against the effects of the uncontrolled entrance of microorganisms and other antigenic particles into Peyer's patch lymphoid follicles. Images PMID:7275318

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

    PubMed

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

    2014-02-01

    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 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 towards bioengineered tooth regeneration. PMID:24345734

  11. Dynamic relationship of the epithelium and mesenchyme during salivary gland initiation: the role of Fgf10

    PubMed Central

    Wells, Kirsty L.; Gaete, Marcia; Matalova, Eva; Deutsch, Danny; Rice, David; Tucker, Abigail S.

    2013-01-01

    Summary Salivary glands provide an excellent model for the study of epithelial–mesenchymal interactions. We have looked at the interactions involved in the early initiation and development of murine salivary glands using classic recombination experiments and knockout mice. We show that salivary gland epithelium, at thickening and initial bud stages, is able to direct salivary gland development in non-gland pharyngeal arch mesenchyme at early stages. The early salivary gland epithelium is therefore able to induce gland development in non-gland tissue. This ability later shifts to the mesenchyme, with non-gland epithelium, such as from the limb bud, able to form a branching gland when combined with pseudoglandular stage gland mesenchyme. This shift appears to involve Fgf signalling, with signals from the epithelium inducing Fgf10 in the mesenchyme. Fgf10 then signals back to the epithelium to direct gland down-growth and bud development. These experiments highlight the importance of epithelial–mesenchymal signalling in gland initiation, controlling where, when and how many salivary glands form. PMID:24167707

  12. Dynamic relationship of the epithelium and mesenchyme during salivary gland initiation: the role of Fgf10.

    PubMed

    Wells, Kirsty L; Gaete, Marcia; Matalova, Eva; Deutsch, Danny; Rice, David; Tucker, Abigail S

    2013-01-01

    Salivary glands provide an excellent model for the study of epithelial-mesenchymal interactions. We have looked at the interactions involved in the early initiation and development of murine salivary glands using classic recombination experiments and knockout mice. We show that salivary gland epithelium, at thickening and initial bud stages, is able to direct salivary gland development in non-gland pharyngeal arch mesenchyme at early stages. The early salivary gland epithelium is therefore able to induce gland development in non-gland tissue. This ability later shifts to the mesenchyme, with non-gland epithelium, such as from the limb bud, able to form a branching gland when combined with pseudoglandular stage gland mesenchyme. This shift appears to involve Fgf signalling, with signals from the epithelium inducing Fgf10 in the mesenchyme. Fgf10 then signals back to the epithelium to direct gland down-growth and bud development. These experiments highlight the importance of epithelial-mesenchymal signalling in gland initiation, controlling where, when and how many salivary glands form. PMID:24167707

  13. 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. PMID:24798790

  14. PES fabric plasma modification

    NASA Astrophysics Data System (ADS)

    Vatuňa, T.; Špatenka, P.; Píchal, J.; Koller, J.; Aubrecht, L.; Wiener, J.

    2004-03-01

    Polyester ranks the upper position in the world fiber production — nearly 54% of the total production of synthetic fibers. Troubles connected with minimizing of the textile hydrophobicity are usually being solved by the textile fibers’ surface chemical modification, but from ecological point of view modification of fabric with low temperature plasma is superior to classical chemical wet processes. Application of various plasmas for PES treatment has been already described. To compare the effectiveness of different plasma sources we performed a series of experiment both in RF and MW plasmas. For working gas nitrogen, oxygen and their mixtures were employed. Internal plasma control was provided by measurement of optical emission spectra. The hydrophilicity degree was determined by the drop test. Paper discusses optimal conditions of the PES fabric plasma treatment.

  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. Tracheal organ cultures as a useful tool to study Felid herpesvirus 1 infection in respiratory epithelium.

    PubMed

    Leeming, Gail; Meli, Marina L; Cripps, Peter; Vaughan-Thomas, Anne; Lutz, Hans; Gaskell, Rosalind; Kipar, Anja

    2006-12-01

    Felid herpesvirus 1 (FeHV-1) is an important feline pathogen of the upper respiratory tract which can be identified in clinical cases by virus isolation and PCR. Studies on the effect and mode of spread of FeHV-1 in the respiratory epithelium, however, have previously only been performed in infected cats. Feline tracheal organ cultures which were inoculated with FeHV-1 at varying multiplicity of infection (MOI) were established. A dose-dependent response was observed. Low MOIs induced multifocal infection in the otherwise viable respiratory epithelium, which allowed monitoring of viral growth over several days. Therefore, tracheal organ cultures represent a suitable model for further study of the morphological and functional effects of FeHV-1 on respiratory epithelium, mimicking the in vivo situation. PMID:16926054

  17. 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

  18. Chronic inflammatory airway diseases: the central role of the epithelium revisited.

    PubMed

    Gohy, S T; Hupin, C; Pilette, C; Ladjemi, M Z

    2016-04-01

    The respiratory epithelium plays a critical role for the maintenance of airway integrity and defense against inhaled particles. Physical barrier provided by apical junctions and mucociliary clearance clears inhaled pathogens, allergens or toxics, to prevent continuous stimulation of adaptive immune responses. The "chemical barrier", consisting of several anti-microbial factors such as lysozyme and lactoferrin, constitutes another protective mechanism of the mucosae against external aggressions before adaptive immune response starts. The reconstruction of damaged respiratory epithelium is crucial to restore this barrier. This review examines the role of the airway epithelium through recent advances in health and chronic inflammatory diseases in the lower conducting airways (in asthma and chronic obstructive pulmonary disease). Better understanding of normal and altered epithelial functions continuously provides new insights into the physiopathology of chronic airway diseases and should help to identify new epithelial-targeted therapies. PMID:27021118

  19. Calcium inhibits the damaging and compensatory proliferative effects of fatty acids on mouse colon epithelium.

    PubMed

    Wargovich, M J; Eng, V W; Newmark, H L

    1984-07-01

    Intrarectal instillations of the fatty acids (FA), lauric, linoleic or oleic acids induce inflammation and superficial lysis of the colon epithelium. This reaction is followed by increases in colonic mitotic activity and the number of cells engaged in DNA synthesis in compensatory regeneration for the cells that were lost. This explains, in part, the promotional effect of dietary fat in carcinogenesis. Concomitant oral administration of calcium salts, as CaCO3, largely reduced the mitogenic effects of fatty acids on colon epithelium, presumably by forming biologically inert calcium soaps. Calcium soap formation of dietary fatty acids may be one natural mechanism by which colon epithelium cells are protected hence reducing the impact of dietary fat on carcinogenesis for this organ. PMID:6744249

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

    PubMed

    van der Gracht, Esmé; Zahner, Sonja; Kronenberg, Mitchell

    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

  1. The cervico-vaginal epithelium during 20 cycles' use of a combined contraceptive vaginal ring.

    PubMed

    Roumen, F J; Boon, M E; van Velzen, D; Dieben, T O; Coelingh Bennink, H J

    1996-11-01

    The aim of the study was to evaluate the influence of a combined contraceptive vaginal ring (CCVR) made of Silastic on the cervico-vaginal epithelium during 20 cycles of use. A total of 76 volunteers used the CCVR releasing 0.120 mg etonogestrel and 0.015 mg ethinyloestradiol daily. Cytological samples were taken of the vaginal epithelium, the ectocervix and the endocervix before the start, at 4 and 12 months, and at the end of the study. Cytology, hormonal profiles, human papilloma virus (HPV) status, DNA-flow cytometry, bacterial flora, and morphometry was performed on these samples. Colposcopy and histopathology of biopsy specimens were performed at the end. No cytological changes of the squamous epithelium or the columnar epithelium were found. HPV was detected in three samples of three different women. At least two of them reverted to HPV negative during the rest of the study period. Aneuploidy was diagnosed in 11 women before the study. Seven of them changed to diploid during the study. No changes from diploid to aneuploid were seen. Aneuploidy was not seen in any of the HPV positive samples. Although bacterial flora showed considerable variation during the study, no significant influence of the CCVR could be established. Morphometrical analysis showed an increasing nucleus:cytoplasm ratio of the squamous cells during the study. Mild dysplasia was detected in one woman at the end of the study. It was concluded that no unfavourable cytological or bacteriological changes of the cervico-vaginal epithelium were demonstrated during 20 cycles of CCVR use. The vaginal epithelium became more progestogenic during the study. PMID:8981130

  2. 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

  3. Influence of amphotericin B on the sodium pump of porcine lens epithelium.

    PubMed

    Delamere, N A; Dean, W L; Stidam, J M; Moseley, A E

    1996-02-01

    Active transport by Na(+)-K(+)-ATPase in the monolayer of lens epithelium is vital for the regulation of sodium and potassium levels within the mass of fiber cells that make up the bulk of the lens. In this study, experiments were conducted using porcine lenses to test whether Na(+)-K(+)-ATPase activity in the epithelium is altered when the permeability of lens cell plasma membranes is increased by the ionophore amphotericin B. After 24 h, sodium was significantly (P < 0.01) elevated in lenses exposed to 5 or 10 microM amphotericin B. Amphotericin B stimulated 86Rb uptake, probably through an increase of cytoplasmic sodium concentration due to increased inward sodium leak; the rate of ouabain-sensitive potassium (86Rb) uptake by intact lenses was significantly increased by amphotericin B at 5 microM (P < 0.05) and 10 microM (P < 0.01). After 24 h, the epithelium from lenses exposed to amphotericin B had an Na(+)-K(+)-ATPase activity that was more than twofold higher (P < 0.01) than the Na(+)-K(+)-ATPase activity in control lenses. By immunoblot, there was an increase in Na(+)-K(+)-ATPase catalytic (alpha) subunit immunoreactive polypeptide in the epithelium of lenses exposed to amphotericin B. The increase stemmed from a marked increase of Na(+)-K(+)-ATPase alpha 2-immunoreactive polypeptide but little change in the amount of alpha 1-immunoreactive protein. As judged by immunoblot experiments, the amount of Na(+)-K(+)-ATPase beta 1-immunoreactive polypeptide also appeared to be higher in the epithelium of amphotericin B-treated lenses compared with control lenses. In summary, these results suggest that in response to a permeability challenge with amphotericin B, the porcine lens epithelium is able to increase the activity of Na(+)-K(+)-ATPase. The same permeability challenge also appears to stimulate the biosynthesis of Na(+)-K(+)-ATPase catalytic subunit as well as glycoprotein subunit polypeptides. PMID:8779908

  4. Cytochrome P-450-dependent monooxygenases in olfactory epithelium of dogs: possible role in tumorigenicity

    SciTech Connect

    Dahl, A.R.; Hadley, W.M.; Hahn, F.F.; Benson, J.M.; McClellan, R.O.

    1982-04-02

    The respiratory tract epithelium of dogs, from the nose to the lungs, was examined for cytochrome P-450 and associated biotransformation activities. In the ethmoturbinates, where olfactory epithelium is located, the amount of cytochrome P-450 was comparable to that in the liver, when measured on the basis of activity per milligram of microsomal protein. The rest of the nasal region also contained large quantities of cytochrome P-450. The presence of these enzymes in the nose may be important in chemical-induced tumorigenesis. The nasal carcinogen hexamethylphosphoramide was shown to be metabolized by nasal microsomal enzymes to another nasal carcinogen, formaldehyde.

  5. [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

  6. 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

  7. Solitons and ionospheric modification

    NASA Technical Reports Server (NTRS)

    Sheerin, J. P.; Nicholson, D. R.; Payne, G. L.; Hansen, P. J.; Weatherall, J. C.; Goldman, M. V.

    1982-01-01

    The possibility of Langmuir soliton formation and collapse during ionospheric modification is investigated. Parameters characterizing former facilities, existing facilities, and planned facilities are considered, using a combination of analytical and numerical techniques. At a spatial location corresponding to the exact classical reflection point of the modifier wave, the Langmuir wave evolution is found to be dominated by modulational instability followed by soliton formation and three-dimensional collapse. The earth's magnetic field is found to affect the shape of the collapsing soliton. These results provide an alternative explanation for some recent observations.

  8. Dual modification of biomolecules.

    PubMed

    Maruani, Antoine; Richards, Daniel A; Chudasama, Vijay

    2016-07-14

    With the advent of novel bioorthogonal reactions and "click" chemistry, an increasing number of strategies for the single labelling of proteins and oligonucleotides have emerged. Whilst several methods exist for the site-selective introduction of a single chemical moiety, site-selective and bioorthogonal dual modification of biomolecules remains a challenge. The introduction of multiple modules enables a plethora of permutations and combinations and can generate a variety of bioconjuguates with many potential applications. From de novo approaches on oligomers to the post-translational functionalisation of proteins, this review will highlight the main strategies to dually modify biomolecules. PMID:27278999

  9. In vivo antioxidant gene expression in human airway epithelium of normal individuals exposed to 100% O2.

    PubMed

    Erzurum, S C; Danel, C; Gillissen, A; Chu, C S; Trapnell, B C; Crystal, R G

    1993-09-01

    Human bronchial epithelium is exquisitely sensitive to high O2 levels, with tracheobronchitis usually developing after 12 h of exposure to 100% O2. To evaluate whether this vulnerability results from inability of the bronchial epithelium to provide adequate antioxidant protection, we quantified antioxidant gene expression in bronchial epithelium of normal volunteers at baseline and after exposure to 100% O2 in vivo. After 14.8 +/- 0.2 h of 100% O2, 24 of 33 individuals had evidence of tracheobronchitis. Baseline gene expression of CuZn superoxide dismutase (SOD), MnSOD, and catalase in bronchial epithelium was very low (CuZnSOD 4.1 +/- 0.8 transcripts/cell, MnSOD 5.1 +/- 0.9, catalase 1.3 +/- 0.2), with control gamma-actin expression relatively abundant (50 +/- 6 transcripts/cell). Importantly, despite 100% O2 exposure sufficient to cause tracheobronchitis in most individuals, antioxidant mRNA transcripts/cell in bronchial epithelium did not increase (P > 0.5). Catalase activity in bronchial epithelium did not change after exposure to hyperoxia (P > 0.05). Total SOD activity increased mildly (P < 0.01) but not sufficiently to protect the epithelium. Together, the very low levels of expression of intracellular antioxidant enzymes and the inability to upregulate expression at the mRNA level with oxidant stress likely have a role in human airway epithelium susceptibility to hyperoxia. PMID:8226538

  10. In vitro absorption of γ-globulin by neonatal intestinal epithelium of the pig

    PubMed Central

    Lecce, James G.

    1966-01-01

    1. An in vitro method, using fluorescent γ-globulin and everted neonatal pig's intestinal slices, for the study of the active transport of large molecules is described. 2. Uptake of γ-globulin occurred within 15 min and required no exogenous substrates. 3. In vitro absorption of γ-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 γ-globulin. 4. Rings of everted intestinal epithelium remained active (still absorbed γ-globulin) after incubating for 4-6 hr in balanced salt solution (BSS). 5. Uptake of γ-globulin required oxygen and sodium and was reversibly inhibited by metabolic antagonists such as iodoacetate, arsenate, fluoride, 4,6-dinitro-ϕ-cresol, phlorrhizin, anaerobiosis and cold. Under the conditions of the test, large colloidal molecules did not inhibit uptake of γ-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. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:4164327

  11. Aspiration cytology of radiation-induced changes of normal breast epithelium

    SciTech Connect

    Bondeson, L.

    1987-05-01

    From a case illustrated, it appears that irradiation may induce changes in normal breast epithelium indistinguishable from malignancy by means of aspiration cytology. This fact must be considered in the choice of diagnostic methods for the evaluation of lesions in irradiated breast tissue.

  12. Luminal Microbes Promote Monocyte–Stem Cell Interactions Across a Healthy Colonic Epithelium

    PubMed Central

    Skoczek, Dagmara A.; Walczysko, Petr; Horn, Nikki; Parris, Alyson; Clare, Simon; Williams, Mark R.

    2014-01-01

    The intestinal epithelium forms a vital barrier between luminal microbes and the underlying mucosal immune system. Epithelial barrier function is maintained by continuous renewal of the epithelium and is pivotal for gut homeostasis. Breaching of the barrier causes mobilization of immune cells to promote epithelial restitution. However, it is not known whether microbes at the luminal surface of a healthy epithelial barrier influence immune cell mobilization to modulate tissue homeostasis. Using a mouse colonic mucosal explant model, we demonstrate that close proximity of luminal microbes to a healthy, intact epithelium results in rapid mucus secretion and movement of Ly6C+7/4+ monocytes closer to epithelial stem cells. These early events are driven by the epithelial MyD88-signaling pathway and result in increased crypt cell proliferation and intestinal stem cell number. Over time, stem cell number and monocyte–crypt stem cell juxtapositioning return to homeostatic levels observed in vivo. We also demonstrate that reduced numbers of tissue Ly6C+ monocytes can suppress Lgr5EGFP+ stem cell expression in vivo and abrogate the response to luminal microbes ex vivo. The functional link between monocyte recruitment and increased crypt cell proliferation was further confirmed using a crypt–monocyte coculture model. This work demonstrates that the healthy gut epithelium mediates communication between luminal bacteria and monocytes, and monocytes can modulate crypt stem cell number and promote crypt cell proliferation to help maintain gut homeostasis. PMID:24907348

  13. A new, albino-beige mouse: giant granules in retinal pigment epithelium.

    PubMed

    Robison, W G; Kuwabara, T

    1978-04-01

    Albino-beige mice were produced in order to combine two experimentally useful characteristics, albinism and lysosomal dysfunction, in the same animal. The retinal pigment epithelium of albino-beige mice formed giant intracellular granules. Exposure of albino-beige mice to white light of 150 foot-candles for 3 to 10 hr induced marked phagocytosis of rod outer segment fragments by the retinal pigment epithelium, resulting in intracellular accumulations of undigested disk membranes within the giant granules. Additional, incompletely processed membranes accumulated as the mice aged or were exposed to 150 foot-candle light for longer periods. Such accumulations of ingested membranes were not observed in the pigment epithelium of exposed or aging albino mice heterozygous for the beige gene. Because of its altered processing of ingested outer segment membranes, this new albino mouse should be useful for studying the possible roles of the retinal pigment epithelium in the maintenance of photoreceptor cells and in their recovery from light damage and other insults. PMID:640784

  14. [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

  15. ADENOCARCINOMA OF THE RETINAL PIGMENT EPITHELIUM IN THE GUPPY POECILIA RETICULATA PETERS

    EPA Science Inventory

    A single case of adenocarcinoma of the retinal pigment epithelium occurred in a guppy, Poecilia reticulata Peters. his is the first such tumor reported from fishes. he left eye of the affected fish was severely exophthalmic because of a large intraocular tumor mass. he tumor, whi...

  16. A COMPARISON BETWEEN MDV PRODUCTION IN FEATHER PULP VERSUS FEATHER FOLLICLE EPITHELIUM (FFE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marek's disease is a lymphoproliferative disease in chickens caused by the alphaherpesvirus Marek's disease virus (MDV). After a cytolytic phase in lymphoid tissue (i.e. thymus, spleen and bursa) the virus travels to the feather follicle epithelium (FFE). The FFE is the only known location that sh...

  17. Clearance of lead-212 ions from rabbit bronchial epithelium to blood.

    PubMed

    James, A C; Greenhalgh, J R; Smith, H

    1977-09-01

    The absorption of 212Pb ions from bronchial epithelium to blood has been investigated in anaesthetized rabbits. The 212Pb ions were introduced by intubation either into the trachea or into smaller, more distal bronchi. Removal from lung was followed by external gamma-counting. Mucociliary clearance to the GI tract was blocked by tracheostomy. Two distinct phases of clearance from bronchial epithelium to blood were observed. Approximately 20% of deposited 212Pb is rapidly absorbed with a half-time of about 4 min, the remainder with a biological half-time of about 9 h, irrespective of the site of instillation in the bronchial tree. Two hours after deposition, the 212Pb remaining in lung was found to be partitioned between mucus and the bronchial epithelium, with a substantial but minor fraction in the epithelium. Uptake of 212Pb in the skeleton was estimated to be about 20% of the 212Pb entering the blood circulation. Removal by the kidneys, at 25%, was comparable with skeletal uptake. These results are compared with previously published work using rodents, dogs and man which demonstrated either rapid or slow absorption but not both phases occuring together. PMID:909929

  18. 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...

  19. [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

  20. 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...

  1. 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. PMID:26772400

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

    PubMed

    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

  3. 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

  4. Co-culture of rat trigeminal ganglion neurons and corneal epithelium.

    PubMed

    Forbes, D J; Pozos, R S; Nelson, J D

    1987-03-01

    Corneal epithelium and the trigeminal ganglion neurons which normally innervate the epithelium have been grown in adjacent chambers of a 35 mm tissue culture plate. Dissociated nerve cells from late embryonic rats were plated inside an 8 mm cloning cylinder attached to the center of the culture plate by silicone grease. In 7-10 days neurites extended out of this inner chamber by growing through the grease seal and along parallel scratches in the collagen coating of the tissue culture plate. Once this occurred, pure corneal epithelial explants were isolated from young adult rats and plated in the area surrounding the cloning cylinder, i.e. in the outer chamber. Cultures were monitored regularly with phase microscopy and, at various times, were fixed for ultrastructural examination. Within 24-48 hours of the epithelial plating, there were both individual neurites and bundles of neurites in contact with the epithelium. This interaction increased substantially over the next few days. Growth cones of the neurites could be seen to approach the microvilli-covered surface of the epithelium, travel over the surface and penetrate between the epithelial cells. This tissue culture model of the innervated ocular surface may prove valuable in the study of a variety of ocular conditions or diseases, as well as provide a means to study functional relationships and mechanisms of cellular interaction between neurons and their target cells. PMID:3556022

  5. 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

  6. 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. PMID:15923093

  7. 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...

  8. Th2-type cytokine-induced mucus metaplasia decreases susceptibility of human bronchial epithelium to rhinovirus infection.

    PubMed

    Jakiela, Bogdan; Gielicz, Anna; Plutecka, Hanna; Hubalewska-Mazgaj, Magdalena; Mastalerz, Lucyna; Bochenek, Grazyna; Soja, Jerzy; Januszek, Rafal; Aab, Alar; Musial, Jacek; Akdis, Mübeccel; Akdis, Cezmi A; Sanak, Marek

    2014-08-01

    Human rhinoviruses (RVs) are a major cause of exacerbations in asthma and other chronic airway diseases. A characteristic feature of asthmatic epithelium is goblet cell metaplasia and mucus hypersecretion. Bronchial epithelium is also an important source of lipid mediators, including pro- and antiinflammatory eicosanoids. By using air-liquid interface cultures of airway epithelium from patients with asthma and nonasthmatic control subjects, we compared RV16 replication-induced changes in mRNA expression of asthma candidate genes and eicosanoid production in the epithelium with or without IL-13-induced mucus metaplasia. Mucus metaplastic epithelium was characterized by a 20-fold less effective replication of RV16 and blunted changes in gene expression; this effect was seen to the same extent in patients with asthma and control subjects. We identified ciliary cells as the main target for RV16 by immunofluorescence imaging and demonstrated that the numbers of ciliary cells decreased in RV16-infected epithelium. RV16 infection of mucociliary epithelium resulted in overexpression of genes associated with bronchial remodeling (e.g., MUC5AC, FGF2, and HBEGF), induction of cyclooxygenase-2, and increased secretion of prostaglandins. These responses were similar in both studied groups. These data indicate that structural changes associated with mucus metaplasia renders airway epithelium less susceptible to RV infection. Thus, exacerbations of the lung disease caused by RV may result from severe impairment in mucociliary clearance or activation of immune defense rather than from preferential infection of mucus metaplastic epithelium. Repeated rhinoviral infections of compromised epithelium may contribute to the remodeling of the airways. PMID:24588727

  9. Relation of chemical structure to spatial distribution of sensory responses in rat olfactory epithelium.

    PubMed

    Scott, J W; Davis, L M; Shannon, D; Kaplan, C

    1996-05-01

    1. Electroolfactogram (EOG) recordings were made in three configurations from the rat olfactory epithelium. Each configuration compared recordings in the dorsomedial recess of the epithelium with recordings in ventral or lateral parts of the epithelium. Most comparisons were made with simultaneous recordings. The exception was a series in which the dorsal recess and lateral space between the base of two turbinate bones were directly exposed for odor application and recording. The spatial distributions of maximal responses were largely independent of recording configuration. 2. Simultaneous recordings compared dorsomedial and lateral sites in the epithelium during stimulation with a series of 50 odorants. The odorants that evoked larger responses in the lateral sites were usually compounds that lacked oxygen containing functional groups (such as the carbonyl group). This was true for straight chain and cyclic alkanes, for terpine compounds, and for aromatic compounds. The major exception was cineole, a bicyclic compound. All compounds containing ketone groups evoked larger dorsomedial responses. The responses of aldehydes and esters depended upon whether they were attached to aliphatic or aromatic chains. 3. In the three types of preparation, the sites responding best to ketones were in the same expression zone of the epithelium according to published maps for the rat and mouse. The sites responding best to odors without functional groups were in the far lateral or ventral region and corresponded to one of the two most lateral and ventral expression zones. This fact suggests that the receptors in these regions have a preference for particular chemical properties. This level of analysis cannot determine whether all receptors in each zone have a stronger response to certain properties of these odorants or whether each zone contains different proportions of receptors with these properties. PMID:8734602

  10. 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

  11. In vitro culture of embryonic mouse intestinal epithelium: cell differentiation and introduction of reporter genes

    PubMed Central

    Quinlan, Jonathan M; Yu, Wei-Yuan; Hornsey, Mark A; Tosh, David; Slack, Jonathan MW

    2006-01-01

    Background Study of the normal development of the intestinal epithelium has been hampered by a lack of suitable model systems, in particular ones that enable the introduction of exogenous genes. Production of such a system would advance our understanding of normal epithelial development and help to shed light on the pathogenesis of intestinal neoplasia. The criteria for a reliable culture system include the ability to perform real time observations and manipulations in vitro, the preparation of wholemounts for immunostaining and the potential for introducing genes. Results The new culture system involves growing mouse embryo intestinal explants on fibronectin-coated coverslips in basal Eagle's medium+20% fetal bovine serum. Initially the cultures maintain expression of the intestinal transcription factor Cdx2 together with columnar epithelial (cytokeratin 8) and mesenchymal (smooth muscle actin) markers. Over a few days of culture, differentiation markers appear characteristic of absorptive epithelium (sucrase-isomaltase), goblet cells (Periodic Acid Schiff positive), enteroendocrine cells (chromogranin A) and Paneth cells (lysozyme). Three different approaches were tested to express genes in the developing cultures: transfection, electroporation and adenoviral infection. All could introduce genes into the mesenchyme, but only to a small extent into the epithelium. However the efficiency of adenovirus infection can be greatly improved by a limited enzyme digestion, which makes accessible the lateral faces of cells bearing the Coxsackie and Adenovirus Receptor. This enables reliable delivery of genes into epithelial cells. Conclusion We describe a new in vitro culture system for the small intestine of the mouse embryo that recapitulates its normal development. The system both provides a model for studying normal development of the intestinal epithelium and also allows for the manipulation of gene expression. The explants can be cultured for up to two weeks, they

  12. Feline Tritrichomonas foetus adhere to intestinal epithelium by receptor-ligand-dependent mechanisms.

    PubMed

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

    2013-02-18

    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 [(3)H] 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. [(3)H] 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

  13. 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

  14. 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

  15. Primary nasal epithelium exposed to house dust mite extract shows activated expression in allergic individuals.

    PubMed

    Vroling, Aram B; Jonker, Martijs J; Luiten, Silvia; Breit, Timo M; Fokkens, Wytske J; van Drunen, Cornelis M

    2008-03-01

    Nasal epithelial cells form the outermost protective layer against environmental factors. However, this defense is not just physical; it has been shown that epithelial cells respond by the production of inflammatory mediators that may affect local immune responses. In this research we set out to characterize potential differences between the responses of nasal epithelium from healthy and allergic individuals to house dust mite (HDM) allergen. These differences will help us to define local mechanisms that could contribute to allergic disease expression. Epithelial cells were cultured from nasal biopsies taken from five healthy and five allergic individuals. These cultures were exposed for 24 hours to culture medium containing HDM allergen, or to culture medium alone. Isolated RNA was used for microarray analysis. Gene-ontology of the response in healthy epithelium revealed mainly up-regulation of chemokines, growth factors, and structural proteins. Moreover, we saw increased expression of two transcription factors (NF-kappaB and AP-1) and their regulatory members. The expression pattern of epithelium from allergic individuals in the absence of the HDM stimulus suggests that it is already in an activated state. Most striking is that, while the already activated NF-kappaB regulatory pathway remained unchanged in allergic epithelium, the AP-1 pathway is down-regulated upon exposure to HDM allergen; this is contrary to what we see in healthy epithelium. Clear differences in the expression pattern exist between epithelial cells isolated from healthy and allergic individuals at baseline and between their responses to allergen exposure; these differences may contribute to the inflammatory response. PMID:17901406

  16. Enterocyte-lymphocyte interactions in the follicle-associated epithelium of the mouse Peyer's patch.

    PubMed Central

    Cremaschi, D; James, P S; Rossetti, C; Smith, M W

    1989-01-01

    1. Measurements of membrane potential (Vm) have been carried out in the follicle-associated epithelium of the mouse Peyer's patch to investigate possible site-dependent anomalies in enterocyte development. Initial heterogeneity in Vm values obtained from carrying out random impalements in the upper third of the follicle-associated epithelium could be described as arising from the presence of three different cell populations. 2. The predominant cell type in this epithelium (T1) had a mean Vm of -35.3 mV which was partly depolarized by increasing concentrations of K+. These cells were not stained with the vital dye Neutral Red. Two other types of cell (T2L and T2H) were recorded together as consecutive negative jumps in Vm, but only in areas of the epithelium previously stained with Neutral Red. T2L behaved like T1 cells to K+ but with a low Vm of -23.3 mV. T2H cells had a high mean Vm of -47.5 mV showing transient hyperpolarization to increasing K+ concentration. 3. The electrophysiological and non-staining properties of T1 cells are similar to those expected from mature enterocytes. The anatomical size, site, staining properties and Vm of T2H cells correspond to those expected for intraepithelial lymphocytes. The low Vm, K+ depolarization and close association of T2L with T2H cells are typical of properties predicted for an immature-type of antigen-transporting enterocyte known to be present in this type of epithelium. 4. The possibility that intraepithelial lymphocytes either slow or reverse a more normal process of development of enterocytes in their immediate vicinity is discussed along with wider aspects of enterocyte-lymphocyte interactions leading to the transfer to enteric antigens across these modified cells. Images Fig. 1 PMID:2778741

  17. 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. PMID:25030175

  18. 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. PMID:24376126

  19. 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...

  20. Perioperative period: immunological modifications.

    PubMed

    Cardinale, F; Chinellato, I; Caimmi, S; Peroni, D G; Franceschini, F; Miraglia Del Giudice, M; Bernardini, R

    2011-01-01

    Surgical stress induces complex modifications in the hemodynamic, metabolic, neuro-hormonal and immune response of the individual. The magnitude of these alterations depends on preoperative events leading to surgery, the severity of surgical trauma, and also on post-operative/post-traumatic complications (multiple hit hypothesis). As in other conditions of tissue damage, surgery trauma is followed by an immune-inflammatory response, initiated at the site of injury by the innate immune system, followed by a compensatory anti-inflammatory (or immunosuppressive) response (CARS), involving mainly cells of the adaptive immune system, which predispose the host to septic complications. The up-regulated inflammatory response, together with a profound impairment of macrophage and cell-mediated immunity, appear to be the cause for patients' increased susceptibility in developing subsequent sepsis after major surgery. PMID:22014920

  1. Enzymatic modification of schizophyllan.

    PubMed

    Leathers, Timothy D; Sutivisedsak, Nongnuch; Nunnally, Melinda S; Price, Neil P J; Stanley, April M

    2015-03-01

    An enzymatic method was developed for the progressive modification of the polysaccharide schizophyllan. Fungal strains Hypocrea nigricans NRRL 62555, Penicillium crustosum NRRL 62558, and Penicillium simplicissimum NRRL 62550 were previously identified as novel sources of β-endoglucanase with specificity towards schizophyllan. Concentrated enzyme preparations from these strains showed specific activities of 1.7-4.3 U β-glucanase/mg protein. Using dilutions of these enzymes in time course digestions, schizophyllan was progressively modified to reduced molecular weight species. Glucose and oligosaccharides were found only in the more complete digestions, and thus modified schizophyllan can be produced quantitatively, without loss, to small molecules. Permethylation analysis confirmed that modified schizophyllan retains the fundamental linkage structure of native schizophyllan. Modified schizophyllan species showed progressively reduced viscosity profiles, and all exhibited pseudoplasticity in response to shear thinning. PMID:25335747

  2. Membrane carbonic anhydrase (IV) and ciliary epithelium. Carbonic anhydrase activity is present in the basolateral membranes of the non-pigmented ciliary epithelium of rabbit eyes.

    PubMed

    Matsui, H; Murakami, M; Wynns, G C; Conroy, C W; Mead, A; Maren, T H; Sears, M L

    1996-04-01

    Carbonic anhydrase inhibitors (CAIs) lower intraocular pressure by reducing aqueous flow. It has been thought that this pharmacologic reduction of aqueous flow is mediated by the ciliary epithelium, but it is not known whether this cellular action is effected by inhibition of the membranal (CA IV) and/or cytosolic (CA II) carbonic anhydrases of the ciliary epithelium. The isolated ciliary epithelial bilayer maintains its anatomic and functional polarity and generates a transepithelial potential difference (TEP) in an Ussing type chamber. Depletion of HCO3-, accomplished either with an HCO3(-)-free solution bathing the epithelial bilayer, or, with addition of freely permeant CAIs to HCO3(-)-containing media, (from either the PE or NPE side of the bilayer) depolarizes the preparation. Addition of CAIs to an HCO3(-)-depleted preparation has no further effect, indicating the specific action of the CAIs. The CAI, 2-p-NH2 benzenesulfonamido-1,3,4,-thiadiazole-5-SO2NH2, linked to polybutadiene maleic acid yields an impermeant polymer of 20000 Da with no loss of activity. At 45 microM this impermeant polymer caused a 60% increase in the SCC, seen only when the compound was applied to the NPE side of the bilayer. This latter result indicates an effect from inhibition of CA IV in the basolateral membranes of the NPE. Thus there are probably two different cellular actions of CAIs upon the ciliary epithelium to reduce aqueous inflow, cytoplasmic and membranal. The action of NPE basolateral membranal CA IV is probably linked to the chloride/bicarbonate exchanger. PMID:8795459

  3. β3GnT2 Maintains Adenylyl Cyclase-3 Signaling and Axon Guidance Molecule Expression in the Olfactory Epithelium

    PubMed Central

    Faden, Ashley A.; Knott, Thomas K.

    2011-01-01

    In the olfactory epithelium (OE), odorant receptor stimulation generates cAMP signals that function in both odor detection and the regulation of axon guidance molecule expression. The enzyme that synthesizes cAMP, adenylyl cyclase 3 (AC3), is coexpressed in olfactory sensory neurons (OSNs) with poly-N-acetyllactosamine (PLN) oligosaccharides determined by the glycosyltransferase β3GnT2. The loss of either enzyme results in similar defects in olfactory bulb (OB) innervation and OSN survival, suggesting that glycosylation may be important for AC3 function. We show here that AC3 is extensively modified with N-linked PLN, which is essential for AC3 activity and localization. On Western blots, AC3 from the wild-type OE migrates diffusely as a heavily glycosylated 200 kDa band that interacts with the PLN-binding lectin LEA. AC3 from the β3GnT2−/− OE loses these PLN modifications, migrating instead as a 140 kDa glycoprotein. Furthermore, basal and forskolin-stimulated cAMP production is reduced 80–90% in the β3GnT2−/− OE. Although AC3 traffics normally to null OSN cilia, it is absent from axon projections that aberrantly target the OB. The cAMP-dependent guidance receptor neuropilin-1 is also lost from β3GnT2−/− OSNs and axons, while semaphorin-3A ligand expression is upregulated. In addition, kirrel2, a mosaically expressed adhesion molecule that functions in axon sorting, is absent from β3GnT2−/− OB projections. These results demonstrate that PLN glycans are essential in OSNs for proper AC3 localization and function. We propose that the loss of cAMP-dependent guidance cues is also a critical factor in the severe axon guidance defects observed in β3GnT2−/− mice. PMID:21525298

  4. Differences in cellular glycoconjugates of quiescent, inflamed, and neoplastic colonic epithelium in colitis and cancer-prone tamarins.

    PubMed Central

    Moore, R.; King, N.; Alroy, J.

    1988-01-01

    In the preceding paper the authors demonstrated that the lectin staining patterns of normal colonic epithelium obtained from colitis and carcinoma-prone cotton top tamarins (CTTs), Saguinus oedipus, a New World primate, differs from colitis- and carcinoma-resistant primate species. In this study they determined the usefulness of cytochemical features in inflamed epithelium as indicators for malignant change. They compared the lectin staining pattern in inflamed mucosa and adjacent mucosa with colonic carcinoma from 8 CTTs with that of 9 clinically healthy CTTs with no histologic evidence of colitis. Deparaffinized sections were labeled with ten biotinylated lectins and stained by the avidin-biotin peroxidase complex method. Numerous significant differences were demonstrated in the lectin staining pattern between normal epithelium and colonic carcinoma; fewer between normal and chronic inflamed epithelium. However, between chronic inflamed epithelium and colonic carcinoma significant staining differences were observed with only two lectins, peanut agglutinin (PNA) and Ulex europaeus agglutinin-I (UEA-I). These findings suggest that there is a progression in alteration of lectin staining pattern from normal epithelium, via chronic colitis, to colonic carcinoma. Furthermore, the differences between chronic colitis and colonic carcinoma are expressed only with those lectins that are associated with malignant transformation of human colonic epithelium. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:3132858

  5. Differences in cellular glycoconjugates of quiescent, inflamed, and neoplastic colonic epithelium in colitis and cancer-prone tamarins.

    PubMed

    Moore, R; King, N; Alroy, J

    1988-06-01

    In the preceding paper the authors demonstrated that the lectin staining patterns of normal colonic epithelium obtained from colitis and carcinoma-prone cotton top tamarins (CTTs), Saguinus oedipus, a New World primate, differs from colitis- and carcinoma-resistant primate species. In this study they determined the usefulness of cytochemical features in inflamed epithelium as indicators for malignant change. They compared the lectin staining pattern in inflamed mucosa and adjacent mucosa with colonic carcinoma from 8 CTTs with that of 9 clinically healthy CTTs with no histologic evidence of colitis. Deparaffinized sections were labeled with ten biotinylated lectins and stained by the avidin-biotin peroxidase complex method. Numerous significant differences were demonstrated in the lectin staining pattern between normal epithelium and colonic carcinoma; fewer between normal and chronic inflamed epithelium. However, between chronic inflamed epithelium and colonic carcinoma significant staining differences were observed with only two lectins, peanut agglutinin (PNA) and Ulex europaeus agglutinin-I (UEA-I). These findings suggest that there is a progression in alteration of lectin staining pattern from normal epithelium, via chronic colitis, to colonic carcinoma. Furthermore, the differences between chronic colitis and colonic carcinoma are expressed only with those lectins that are associated with malignant transformation of human colonic epithelium. PMID:3132858

  6. EFFECT OF DEATH-TO-PRESERVATION TIME ON DONOR CORNEAL EPITHELIUM

    PubMed Central

    Van Meter, Woodford S; Katz, Douglas G; White, Harrison; Gayheart, Robert

    2005-01-01

    Purpose Surface disease is one of multiple variables affecting the quality of the postkeratoplasty donor cornea. Trauma to Bowman’s layer before and during harvesting can denude the donor epithelium and result in epithelial defects in the donor following penetrating keratoplasty. Eye banks use death-to-preservation (DP) time intervals as long as 18 hours. This study evaluates the effects of higher DP time on the donor epithelium in storage medium and immediately following keratoplasty. Methods Eighty-one consecutive corneas were procured by the University of Kentucky Eye Bank, rated by one technician (H.W.), and used by one surgeon (W.S.V.) for elective penetrating keratoplasty. Donor records were retrospectively reviewed for age, DP time, and epithelial condition. All corneas were harvested and evaluated according to Eye Bank Association of America standards. Donor charts were reviewed for DP time and for condition of the epithelium in storage. Recipient charts were reviewed for epithelial defects following keratoplasty. Results Average DP time of all 81 donor corneas was 6:18 hours (ie, 6 hours, 18 minutes). Average DP time of 13 corneas with epithelial sloughing was 7:02 (range, 2:01 to 12:25) hours, and nine (69%) had DP time longer than 6 hours. Average DP time of 68 corneas with no sloughing was 6:09 (range, 1:59 to 11:03) hours (P < .32). Average DP of 28 recipients with epithelial defect on day 1 was 8:01 (range, 3:41 to 12:49), and average DP in 53 patients with an intact epithelium on day 1 was 5:23 (range, 1:59 to 9:46) (P < .001). The percentage of postoperative patients with epithelial defects in the graft on day 1 rose from 14% when DP was less than 4 hours to 100% when DP was greater than 10 hours. Average DP in 13 donors under age 30 was 8.3 hours. Conclusion DP time longer than 6 hours was more likely to result in sloughing of the donor epithelium. Care of donor epithelium prior to harvesting becomes increasingly important with DP times longer

  7. Site-specific population dynamics and variable olfactory marker protein expression in the postnatal canine olfactory epithelium

    PubMed Central

    Bock, Patricia; Rohn, Karl; Beineke, Andreas; Baumgärtner, Wolfgang; Wewetzer, Konstantin

    2009-01-01

    The main olfactory epithelium is a pseudostratified columnar epithelium that displays neurogenesis over the course of a lifetime. New olfactory neurons arise basally and are transferred to the middle third of the epithelium during maturation. It is generally believed that this pattern is present throughout the olfactory area. In the present study, we show that the postnatal canine olfactory epithelium is composed of two distinct types of epithelium, designated A and B, which not only differ in olfactory neuron morphology, marker expression and basal cell proliferation but also display a patchy distribution and preferential localization within the nasal cavity. Type A epithelium, abundant in the caudal part of the olfactory area, contains well-differentiated olfactory neurons positive for olfactory marker protein but low numbers of immature neurons and proliferating basal cells, as visualized by TrkB/Human Natural Killer-1 (HNK-1) glyco-epitope and Ki-67 immunostaining, respectively. In contrast, type B epithelium is mainly found in the rostral part and contains smaller and elongated neurons that display increased levels of TrkB/Human Natural Killer-1 (HNK-1) glyco-epitope immunoreactivity and a higher number of Ki-67-positive basal cells but lower and variable levels of olfactory marker protein. The vomeronasal organ displays a uniform distribution of molecular markers and proliferating basal cells. The observation that olfactory marker protein in type A and B epithelium is preferentially localized to the nucleus and cytoplasm, respectively, implies correlation between subcellular localization and olfactory neuron maturation and may indicate distinct functional roles of olfactory marker protein. Whether the site-specific population dynamics in the postnatal canine olfactory epithelium revealed in the present study are modulated by physiological parameters, such as airflow, has to be clarified in future studies. PMID:19788548

  8. Readout of Epigenetic Modifications

    PubMed Central

    Patel, Dinshaw J.; Wang, Zhanxin

    2015-01-01

    This review focuses on a structure-based analysis of histone posttranslational modification (PTM) readout, where the PTMs serve as docking sites for reader modules as part of larger complexes displaying chromatin modifier and remodeling activities, with the capacity to alter chromatin architecture and templated processes. Individual topics addressed include the diversity of reader-binding pocket architectures and common principles underlying readout of methyl-lysine and methyl-arginine marks, their unmodified counterparts, as well as acetyl-lysine and phosphoserine marks. The review also discusses the impact of multivalent readout of combinations of PTMs localized at specific genomic sites by linked binding modules on processes ranging from gene transcription to repair. Additional topics include cross talk between histone PTMs, histone mimics, epigenetic-based diseases, and drug-based therapeutic intervention. The review ends by highlighting new initiatives and advances, as well as future challenges, toward the promise of enhancing our structural and mechanistic understanding of the readout of histone PTMs at the nucleosomal level. PMID:23642229

  9. 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

  10. 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…

  11. Primary Air-Liquid Interface Culture of Nasal Epithelium for Nasal Drug Delivery.

    PubMed

    Ong, Hui Xin; Jackson, Claire L; Cole, Janice L; Lackie, Peter M; Traini, Daniela; Young, Paul M; Lucas, Jane; Conway, Joy

    2016-07-01

    Nasal drug administration is a promising alternative to oral and parenteral administration for both local and systemic delivery of drugs. The benefits include its noninvasive nature, rapid absorption, and circumvention of first pass metabolism. Hence, the use of an in vitro model using human primary nasal epithelial cells could be key to understanding important functions and parameters of the respiratory epithelium. This model will enable investigators to address important and original research questions using a biologically relevant in vitro platform that mimics the in vivo nasal epithelial physiology. The purpose of this study was to establish, systematically characterize, and validate the use of a primary human nasal epithelium model cultured at the air-liquid interface for the study of inflammatory responses and drug transport and to simultaneously quantify drug effects on ciliary activity. PMID:27223825

  12. 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

  13. [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. PMID:25739486

  14. 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

  15. 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

  16. [Fine structure of the fundic gland zone epithelium in various eastern African ruminants].

    PubMed

    Weyrauch, K D; Saber, A S

    1985-01-01

    Light- and electron microscopic investigations were conducted on the epithelium of the area glandulae gastricae propriae of the abomasum, using material of 12 East African game ruminants of nine species. The members of the main feeding categories (Hofmann, Stewart 1972): concentrate selector, roughage eater and intermediate feeder did not differ much in the ultrastructure of the fundic stomach epithelium but showed greater differences with respect to the height and shape of the glandular tubules and the arrangement of the epithelial cell types. Specifically the following cell types were observed: mucoid cells, chief cells, parietal cells, seven different endocrine cells, tuft cells and two types of migrating cells. In some epithelial celltypes of the concentrate selector dikdik, cristalloid cytoplasmic inclusions were found. PMID:4014717

  17. The nasal cavity of the sheep and its olfactory sensory epithelium.

    PubMed

    Barrios, Arthur William; Sanchez Quinteiro, Pablo; Salazar, Ignacio

    2014-12-01

    Macro and microdissection methods, conventional histology and immunohistochemical procedures were used to investigate the nasal cavity and turbinate complex in fetal and adult sheep, with special attention to the ethmoturbinates, the vestibular mucosa, and the septal mucosa posterior to the vomeronasal organ. The ectoturbinates, which are variable in number and size, emerge and develop later than the endoturbinates. The olfactory sensory epithelium is composed of basal cells, neurons, and sustentacular cells organized in strata, but numerous different types are distinguishable on the basis of their thickness and other properties; all variants are present on the more developed turbinates, endoturbinates II and III. Mature neurons and olfactory nerve bundles express olfactory marker protein. We found no structure with the characteristics that in mouse define the septal organ or the ganglion of Grüneberg. Our results thus suggest that in sheep olfactory sensory neurons are exclusively concentrated in the main olfactory epithelium and (to a lesser extent) in the vomeronasal organ. PMID:25213000

  18. 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.

  19. TGFβ signaling in lung epithelium regulates bleomycin-induced alveolar injury and fibroblast recruitment.

    PubMed

    Degryse, Amber L; Tanjore, Harikrishna; Xu, Xiaochuan C; Polosukhin, Vasiliy V; Jones, Brittany R; Boomershine, Chad S; Ortiz, Camila; Sherrill, Taylor P; McMahon, Frank B; Gleaves, Linda A; Blackwell, Timothy S; Lawson, William E

    2011-06-01

    The response of alveolar epithelial cells (AECs) to lung injury plays a central role in the pathogenesis of pulmonary fibrosis, but the mechanisms by which AECs regulate fibrotic processes are not well defined. We aimed to elucidate how transforming growth factor-β (TGFβ) signaling in lung epithelium impacts lung fibrosis in the intratracheal bleomycin model. Mice with selective deficiency of TGFβ receptor 2 (TGFβR2) in lung epithelium were generated and crossed to cell fate reporter mice that express β-galactosidase (β-gal) in cells of lung epithelial lineage. Mice were given intratracheal bleomycin (0.08 U), and the following parameters were assessed: AEC death by terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling assay, inflammation by total and differential cell counts from bronchoalveolar lavage, fibrosis by scoring of trichrome-stained lung sections, and total lung collagen content. Mice with lung epithelial deficiency of TGFβR2 had improved AEC survival, despite greater lung inflammation, after bleomycin administration. At 3 wk after bleomycin administration, mice with epithelial TGFβR2 deficiency showed a significantly attenuated fibrotic response in the lungs, as determined by semiquantitatve scoring and total collagen content. The reduction in lung fibrosis in these mice was associated with a marked decrease in the lung fibroblast population, both total lung fibroblasts and epithelial-to-mesenchymal transition-derived (S100A4(+)/β-gal(+)) fibroblasts. Attenuation of TGFβ signaling in lung epithelium provides protection from bleomycin-induced fibrosis, indicating a critical role for the epithelium in transducing the profibrotic effects of this cytokine. PMID:21441353

  20. Localization and function of the electrical oscillation in electroreceptive ampullary epithelium from skates.

    PubMed Central

    Lu, J; Fishman, H M

    1995-01-01

    A steady, spontaneous current oscillation (1 nA p-p) occurs in voltage-clamped, isolated ampullary organs (canal, ampulla, and nerve) from skates (Raja). Spectral analysis showed that energy in the oscillation was confined to a narrow band of frequencies (3 Hz) about a fundamental frequency (32 Hz at 20 degrees C) and in harmonics. The frequency of the oscillation was temperature dependent (increasing from 21 to 33 Hz for increases in temperature from 13 degrees C to 21 degrees C). The addition of 0.5 microM tetrodotoxin to the basal side of the ampullary epithelium eliminated afferent nerve activity but had no effect on the epithelial oscillation, indicating that the oscillation is not generated or induced by afferent nerve activity. Nitrendipine (2 microM) added to the solution bathing the basal side of the ampullary epithelium abolished the oscillation rapidly (within minutes), but a steady-state negative conductance (i.e., real part of the complex admittance < 0) generated by the preparation remained for 36 min. Conversely, nitrendipine (50 microM) added to the perfusate (artificial sea water) of the apical side eliminated the negative conductance rapidly (18.5 min) but had no effect on the spontaneous oscillation for more than 1 h. The effect and the elapsed time for an effect of nitrendipine after separate applications to the basal and apical membrane surfaces of ampullary epithelium suggest that 1) the negative conductance and the oscillation are generated independently in apical and basal membranes, respectively, and 2) both processes involve L-type Ca channels. Furthermore, the addition of tetraethylammonium (2 mM) to the basal side eliminated both the oscillation and the postsynaptic response to voltage clamps (< or = 100 microV) of the ampullary epithelium in the operational voltage range of the afferent nerve. This result suggests that the basal membrane oscillation functions in neurotransmitter release from presynaptic (basal) membranes. Images FIGURE

  1. Fluorescence lifetime imaging microscopy reveals quenching of fluorescein within corneal epithelium.

    PubMed

    Glasgow, Ben J

    2016-06-01

    Topical application of fluorescein results in background fluorescence of normal corneal epithelial cells. The fluorescence appears relatively weak and is often ignored clinically. The concentrations of fluorescein applied clinically exceed the threshold for self quenching. The possibility that exuberant topical concentrations of fluorescein result in quenching of fluorescence in tears and normal corneal epithelium is explored. Fluorescence lifetime measurements are sensitive to quenching and are less vulnerable to inner filter effect than steady state measurements. The types of fluorescence lifetime quenching often report informative molecular interactions. Therefore, fluorescence lifetime confocal imaging was performed in solutions, tears and corneal epithelium removed by membrane cytology following applied fluorescein. Amplitude averaged fluorescence lifetimes (τamp) were measured with time resolved single photon counting using a pulsed diode laser for excitation of fluorescein. Lifetime decays were fit to multi-exponential models with least squares analysis. Stern-Volmer plots for both intensity (I) and (τamp) were determined. Stern-Volmer plots demonstrated both dynamic and static quenching components (R(2) = 0.98 exponential fit, I0/I). Plots of τamp versus concentration of fluorescein revealed a linear relationship. Immediately after fluorescein application, quenching was evident in tears (τamp < 1 ns) versus tears sampled after 5 min (τamp = 3.7 ns). Corneal epithelium showed quenching (τamp ≤ 2 ns) from 1 to 16 min post fluorescein instillation. Clinical concentrations of fluorescein show self-quenching but rapidly dilute as tears turnover. Intracellular quenching occurs in normal corneal epithelium. Lifetime decay curves suggest complex mechanisms are involved. Quenching is a plausible explanation for the low fluorescence background observed clinically. PMID:27106141

  2. TGFβ signaling in lung epithelium regulates bleomycin-induced alveolar injury and fibroblast recruitment

    PubMed Central

    Degryse, Amber L.; Tanjore, Harikrishna; Xu, Xiaochuan C.; Polosukhin, Vasiliy V.; Jones, Brittany R.; Boomershine, Chad S.; Ortiz, Camila; Sherrill, Taylor P.; McMahon, Frank B.; Gleaves, Linda A.; Blackwell, Timothy S.

    2011-01-01

    The response of alveolar epithelial cells (AECs) to lung injury plays a central role in the pathogenesis of pulmonary fibrosis, but the mechanisms by which AECs regulate fibrotic processes are not well defined. We aimed to elucidate how transforming growth factor-β (TGFβ) signaling in lung epithelium impacts lung fibrosis in the intratracheal bleomycin model. Mice with selective deficiency of TGFβ receptor 2 (TGFβR2) in lung epithelium were generated and crossed to cell fate reporter mice that express β-galactosidase (β-gal) in cells of lung epithelial lineage. Mice were given intratracheal bleomycin (0.08 U), and the following parameters were assessed: AEC death by terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling assay, inflammation by total and differential cell counts from bronchoalveolar lavage, fibrosis by scoring of trichrome-stained lung sections, and total lung collagen content. Mice with lung epithelial deficiency of TGFβR2 had improved AEC survival, despite greater lung inflammation, after bleomycin administration. At 3 wk after bleomycin administration, mice with epithelial TGFβR2 deficiency showed a significantly attenuated fibrotic response in the lungs, as determined by semiquantitatve scoring and total collagen content. The reduction in lung fibrosis in these mice was associated with a marked decrease in the lung fibroblast population, both total lung fibroblasts and epithelial-to-mesenchymal transition-derived (S100A4+/β-gal+) fibroblasts. Attenuation of TGFβ signaling in lung epithelium provides protection from bleomycin-induced fibrosis, indicating a critical role for the epithelium in transducing the profibrotic effects of this cytokine. PMID:21441353

  3. 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

  4. 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

  5. Similar Squamous Cell Carcinoma Epithelium microRNA Expression in Never Smokers and Ever Smokers

    PubMed Central

    Kolokythas, Antonia; Zhou, Yalu; Schwartz, Joel L.; Adami, Guy R.

    2015-01-01

    The incidence of oral tumors in patients who never used mutagenic agents such as tobacco is increasing. In an effort to better understand these tumors we studied microRNA (miRNA) expression in tumor epithelium of never tobacco users, tumor epithelium of ever tobacco users, and nonpathological control oral epithelium. A comparison of levels among 372 miRNAs in 12 never tobacco users with oral squamous cell carcinoma (OSCC) versus 10 healthy controls was made using the reverse transcription quantitative polymerase chain reaction. A similar analysis was done with 8 ever tobacco users with OSCC. These comparisons revealed miR-10b-5p, miR-196a-5p, and miR-31-5p as enriched in the tumor epithelium in OSCC of both never and ever tobacco users. Examination of The Cancer Genome Atlas (TCGA) project miRNA data on 305 OSCCs and 30 controls revealed 100% of those miRNAs enriched in never smoker OSCCs in this patient group were also enriched in ever smoker OSCCs. Nonsupervised clustering of TCGA OSCCs was suggestive of two or four subgroups of tumors based on miRNA levels with limited evidence for differences in tobacco exposure among the groups. Results from both patient groups together stress the importance of miR196a-5p in OSCC malignancy in both never and ever smokers, and emphasize the overall similarity of miRNA expression in OSCCs in these two risk groups. It implies that there may be great similarity in etiology of OSCC in never and ever smokers and that classifying OSCC based on tobacco exposure may not be helpful in the clinic. PMID:26544609

  6. Keratinocyte growth factor accelerates wound closure in airway epithelium during cyclic mechanical strain.

    PubMed

    Waters, C M; Savla, U

    1999-12-01

    The airway epithelium may be damaged by inhalation of noxious agents, in response to pathogens, or during endotracheal intubation and mechanical ventilation. Maintenance of an intact epithelium is important for lung fluid balance, and the loss of epithelium may stimulate inflammatory responses. Epithelial repair in the airways following injury must occur on a substrate that undergoes cyclic elongation and compression during respiration. We have previously shown that cyclic mechanical strain inhibits wound closure in the airway epithelium (Savla and Waters, 1998b). In this study, we investigated the stimulation of epithelial wound closure by keratinocyte growth factor (KGF) in vitro and the mechanisms by which KGF overcomes the inhibition due to mechanical strain. Primary cultures of normal human bronchial epithelial cells (NHBE) and a cell line of human airway epithelial cells, Calu 3, were grown on Silastic membranes, and a wound was scraped across the well. The wells were then exposed to cyclic strain using the Flexercell Strain Unit, and wound closure was measured. While cyclic elongation (20% maximum) and cyclic compression (approximately 2%) both inhibited wound closure in untreated wells, treatment with KGF (50 ng/ml) significantly accelerated wound closure and overcame the inhibition due to cyclic strain. Since wound closure involves cell spreading, migration, and proliferation, we investigated the effect of cyclic strain on cell area, cell-cell distance, and cell velocity at the wound edge. While the cell area increased in unstretched monolayers, the cell area of monolayers in compressed regions decreased significantly. Treatment with KGF increased the cell area in both cyclically elongated and compressed cells. Also, when cells were treated with KGF, cell velocity was significantly increased in both static and cyclically strained monolayers, and cyclic strain did not inhibit cell migration. These results suggest that KGF is an important factor in

  7. Lactobacillus reuteri Inhibition of Enteropathogenic Escherichia coli Adherence to Human Intestinal Epithelium

    PubMed Central

    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

  8. 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

  9. 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

  10. 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

  11. Reconstruction of conjunctival epithelium-like tissue using a temperature-responsive culture dish

    PubMed Central

    Yao, Qinke; Zhu, Mengyu; Chen, Junzhao; Shao, Chunyi; Yan, Chenxi; Wang, Zi; Fan, Xianqun; Gu, Ping

    2015-01-01

    Purpose To study the feasibility of engineering conjunctival epithelial cell sheets on a temperature-responsive culture dish for ocular surface reconstruction. Methods Rabbit conjunctival epithelial cells (rCjECs) were cultured in DMEM/F-12 (1:1) medium. The morphology and phenotype of the rCjECs were confirmed with phalloidin staining, periodic acid–Schiff (PAS) staining, and immunocytochemistry. The rCjECs cultured on a temperature-responsive culture dish for 10 days produced confluent conjunctival epithelial cell sheets. Then, the phenotype, structure, and function of the conjunctival epithelial cell sheets were examined. Results The conjunctival epithelial cells were compact, uniform, and cobblestone shape. All cultured conjunctival epithelial cells were harvested as intact cell sheets by reducing the culture temperature to 20 °C. Conjunctival epithelial cells were stratified in four to five cell layers similar to the conjunctival epithelium. CCK-8 analysis, 5-bromo-2’-deoxyuridine (BrdU) staining, and the live and dead viability assay confirmed that viable proliferation cells were retained in the cell sheets. Immunohistochemistry for CK4, CK19, and MUC5AC showed the cell sheets still maintained characteristics of the conjunctival epithelium. Conclusions A temperature-responsive culture dish enables fabrication of viable conjunctival epithelial cell sheets with goblet cells and proliferative cells. Conjunctival epithelial cell sheets will be promising for reconstruction of the conjunctival epithelium. PMID:26396489

  12. 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

  13. 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

  14. 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

  15. Adjudin, a potential male contraceptive, exerts its effects locally in the seminiferous epithelium of mammalian testes

    PubMed Central

    Mok, Ka-Wai; Mruk, Dolores D; Lie, Pearl P Y; Lui, Wing-Yee; Cheng, C Yan

    2015-01-01

    Adjudin is a derivative of 1H-indazole-3-carboxylic acid that was shown to have potent anti-spermatogenic activity in rats, rabbits, and dogs. It exerts its effects most notably locally in the apical compartment of the seminiferous epithelium, behind the blood–testis barrier, by disrupting adhesion of germ cells, most notably spermatids to the Sertoli cells, thereby inducing release of immature spermatids from the epithelium that leads to infertility. After adjudin is metabolized, the remaining spermatogonial stem cells and spermatogonia repopulate the seminiferous epithelium gradually via spermatogonial self-renewal and differentiation, to be followed by meiosis and spermiogenesis, and thus fertility rebounds. Recent studies in rats have demonstrated unequivocally that the primary and initial cellular target of adjudin in the testis is the apical ectoplasmic specialization, a testis-specific anchoring junction type restricted to the interface between Sertoli cells and elongating spermatids (from step 8 to 19 spermatids). In this review, we highlight some of the recent advances and obstacles regarding the possible use of adjudin as a male contraceptive. PMID:21307270

  16. Purification and characterization of factors produced by Aspergillus fumigatus which affect human ciliated respiratory epithelium.

    PubMed Central

    Amitani, R; Taylor, G; Elezis, E N; Llewellyn-Jones, C; Mitchell, J; Kuze, F; Cole, P J; Wilson, R

    1995-01-01

    The mechanisms by which Aspergillus fumigatus colonizes the respiratory mucosa are unknown. Culture filtrates of eight of nine clinical isolates of A. fumigatus slowed ciliary beat frequency and damaged human respiratory epithelium in vitro. These changes appeared to occur concurrently. Culture filtrates of two clinical isolates of Candida albicans had no effect on ciliated epithelium. We have purified and characterized cilioinhibitory factors of a clinical isolate of A. fumigatus. The cilioinhibitory activity was heat labile, reduced by dialysis, and partially extractable into chloroform. The activity was associated with both high- and low-molecular-weight factors, as determined by gel filtration on Sephadex G-50. A low-molecular-weight cilioinhibitory factor was further purified by reverse-phase high-performance liquid chromatography and shown by mass spectrometry to be gliotoxin, a known metabolite of A. fumigatus. Gliotoxin significantly slowed ciliary beat frequency in association with epithelial damage at concentrations above 0.2 microgram/ml; other Aspergillus toxins, i.e., fumagillin and helvolic acid, were also cilioinhibitory but at much higher concentrations. High-molecular-weight (> or = 35,000 and 25,000) cilioinhibitory materials had neither elastolytic nor proteolytic activity and remain to be identified. Thus, A. fumigatus produces a number of biologically active substances which slow ciliary beating and damage epithelium and which may influence colonization of the airways. PMID:7543879

  17. Detection of the hyaluronan receptor CD44 in the bovine oviductal epithelium.

    PubMed

    Bergqvist, Ann-Sofi; Yokoo, Masaki; Båge, Renée; Sato, Eimei; Rodríguez-Martínez, Heriberto

    2005-08-01

    Hyaluronan is involved in fundamental reproductive events such as sperm storage in the female reproductive tract, fertilization, and early embryo development, these functions are presumably mediated by its major cell surface receptor, CD44. The present study was conducted to investigate the presence and localization of CD44 in the bovine oviductal epithelium, using immunohistochemical and Western blot methods on tissue sections and epithelial cell extracts collected from the uterotubal junction (UTJ), isthmus, and ampulla of animals in the oestrus or luteal phase of the oestrous cycle. While positive immunolabelling for CD44 was found on the ad-luminal surface and supra-nuclear region of epithelial cells in all tubal segments investigated, in the UTJ, there were epithelial cells in which the entire cytoplasm positively stained. We found no differences in terms of CD44-positive staining between the different stages of the oestrous cycle. Presence of CD44 was detected by Western blotting in the tubal epithelium as a single band at 200 kDa. Although it appeared in all tubal segments, the expression of CD44 protein was more accentuated in the sperm reservoir (UTJ) than in the other segments. This is the first time CD44 has been detected in the epithelium of the tubal sperm reservoir in cattle, suggesting a pathway for the action of hyaluronan in this segment. PMID:15846044

  18. Response of the hammerhead shark olfactory epithelium to amino acid stimuli.

    PubMed

    Tricas, Timothy C; Kajiura, Stephen M; Summers, Adam P

    2009-10-01

    Sharks and rays are highly sensitive to chemical stimuli in their natural environment but several hypotheses predict that hammerhead sharks, with their expanded head and enlarged olfactory epithelium, have particularly acute olfactory systems. We used the electro-olfactogram (EOG) technique to compare the relative response of the scalloped hammerhead shark (Sphyrna lewini) olfactory epithelium to 20 proteinogenic amino acids and determine the sensitivity for 6 amino acids. At micromolar concentrations, cysteine evoked the greatest EOG response which was approximately twice as large as that of alanine. The weakest response was obtained for proline followed by aspartic acid and isoleucine. The olfactory epithelium showed adaptation to sequential stimulation, and recovery was related to the inter-stimulus time period. Estimated EOG response thresholds were in the sub-nanomolar range for both alanine (9.2 x 10(-11) M) and cysteine (8.4 x 10(-10) M) and in the micromolar range for proline and serine. These thresholds from 10(-10) to 10(-6) M for the scalloped hammerhead shark are comparable or lower than those reported for other teleost and elasmobranch species. Future work should focus on binary and more complex compounds to test for competition and cross-adaptation for different classes of peripheral receptors, and their responses to molecules found in biologically relevant stimuli. PMID:19711087

  19. Maintenance of sweat glands by stem cells located in the acral epithelium.

    PubMed

    Ohe, Shuichi; Tanaka, Toshihiro; Yanai, Hirotsugu; Komai, Yoshihiro; Omachi, Taichi; Kanno, Shohei; Tanaka, Kiyomichi; Ishigaki, Kazuhiko; Saiga, Kazuho; Nakamura, Naohiro; Ohsugi, Haruyuki; Tokuyama, Yoko; Atsumi, Naho; Hisha, Hiroko; Yoshida, Naoko; Kumano, Keiki; Yamazaki, Fumikazu; Okamoto, Hiroyuki; Ueno, Hiroo

    2015-10-23

    The skin is responsible for a variety of physiological functions and is critical for wound healing and repair. Therefore, the regenerative capacity of the skin is important. However, stem cells responsible for maintaining the acral epithelium had not previously been identified. In this study, we identified the specific stem cells in the acral epithelium that participate in the long-term maintenance of sweat glands, ducts, and interadnexal epidermis and that facilitate the regeneration of these structures following injury. Lgr6-positive cells and Bmi1-positive cells were found to function as long-term multipotent stem cells that maintained the entire eccrine unit and the interadnexal epidermis. However, while Lgr6-positive cells were rapidly cycled and constantly supplied differentiated cells, Bmi1-positive cells were slow to cycle and occasionally entered the cell cycle under physiological conditions. Upon irradiation-induced injury, Bmi1-positive cells rapidly proliferated and regenerated injured epithelial tissue. Therefore, Bmi1-positive stem cells served as reservoir stem cells. Lgr5-positive cells were rapidly cycled and maintained only sweat glands; therefore, we concluded that these cells functioned as lineage-restricted progenitors. Taken together, our data demonstrated the identification of stem cells that maintained the entire acral epithelium and supported the different roles of three cellular classes. PMID:26362184

  20. 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

  1. 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

  2. Patterned Collagen Fibers Orient Branching Mammary Epithelium through Distinct Signaling Modules

    PubMed Central

    Brownfield, Douglas G.; Venugopalan, Gautham; Lo, Alvin; Mori, Hidetoshi; Tanner, Kandice; Fletcher, Daniel A.; Bissell, Mina J.

    2013-01-01

    Summary For decades, the work of cell and developmental biologists has demonstrated the striking ability of the mesenchyme and the stroma to instruct epithelial form and function in the mammary gland [1–3], but the role of extracellular matrix (ECM) molecules in mammary pattern specification has not been elucidated. Here, we show that stromal collagen I (Col-I) fibers in the mammary fat pad are axially oriented prior to branching morphogenesis. Upon puberty, the branching epithelium orients along these fibers, thereby adopting a similar axial bias. To establish a causal relationship from Col-I fiber to epithelial orientation, we embedded mammary organoids within axially oriented Col-I fiber gels and observed dramatic epithelial co-orientation. Whereas a constitutively active form of Rac1, a molecule implicated in cell motility, prevented a directional epithelial response to Col-I fiber orientation, inhibition of the RhoA/Rho-associated kinase (ROCK) pathway did not. However, time-lapse studies revealed that, within randomly oriented Col-I matrices, the epithelium axially aligns fibers at branch sites via RhoA/ROCK-mediated contractions. Our data provide an explanation for how the stromal ECM encodes architectural cues for branch orientation as well as how the branching epithelium interprets and reinforces these cues through distinct signaling processes. PMID:23562267

  3. Patterned collagen fibers orient branching mammary epithelium through distinct signaling modules.

    PubMed

    Brownfield, Douglas G; Venugopalan, Gautham; Lo, Alvin; Mori, Hidetoshi; Tanner, Kandice; Fletcher, Daniel A; Bissell, Mina J

    2013-04-22

    For decades, the work of cell and developmental biologists has demonstrated the striking ability of the mesenchyme and the stroma to instruct epithelial form and function in the mammary gland, but the role of extracellular matrix (ECM) molecules in mammary pattern specification has not been elucidated. Here, we show that stromal collagen I (Col-I) fibers in the mammary fat pad are axially oriented prior to branching morphogenesis. Upon puberty, the branching epithelium orients along these fibers, thereby adopting a similar axial bias. To establish a causal relationship from Col-I fiber to epithelial orientation, we embedded mammary organoids within axially oriented Col-I fiber gels and observed dramatic epithelial co-orientation. Whereas a constitutively active form of Rac1, a molecule implicated in cell motility, prevented a directional epithelial response to Col-I fiber orientation, inhibition of the RhoA/Rho-associated kinase (ROCK) pathway did not. However, time-lapse studies revealed that, within randomly oriented Col-I matrices, the epithelium axially aligns fibers at branch sites via RhoA/ROCK-mediated contractions. Our data provide an explanation for how the stromal ECM encodes architectural cues for branch orientation as well as how the branching epithelium interprets and reinforces these cues through distinct signaling processes. PMID:23562267

  4. 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. PMID:25529641

  5. Electrolyte transport across a simple epithelium. Steady-state and transient analysis.

    PubMed Central

    Weinstein, A M; Stephenson, J L

    1979-01-01

    A simple transporting epithelium is represented as a cellular compartment, compliant in all dimensions, and a paracellular channel, of arbitrary shape, between well-stirred mucosal ans serosal baths. The equations for mass balance, Poiseuille flow, and the Nernst-Planck equation are used to describe the continuous behavior of the system along cell and channel, whereas passive transport across membranes is given by the relations of Kedem and Katchalsky. Time-dependent terms are retained to permit study of transient phenomena. Boundary conditions at the baths demand only mass conservation and specify no a priori estimates of the system variables. A numerical model containing Na+,K+,Cl-, and impermeant cellular anions is formulated with membrane parameters taken from the literature on Necturus gallbladder. The differential equations are represented as a finite difference scheme and solved using Newton's method. It appears that apical cellular NaCl cotransport is necessary to obtain a reasonable cell chloride concentration. Investigation of the osmolality of the transepithelial flow shows that at steady state a leaky epithelium cannot separate baths of substantially different tonicity, although this does not guarantee isotonic transport between equiosmolar media. Changes in bath pressure, application of transepithelial electrical potential, and simulation of ion-substitution experiments are performed to understand the role of membrane permeabilities in determining the dynamic behavior of the epithelium. PMID:233579

  6. Scale morphology of Prochilodus lineatus with emphasis on the scale epithelium.

    PubMed

    Alves, R M S; Pereira, B F; Pitol, D L; Senhorini, J A; Alcântara-Rocha, R C G; Caetano, F H

    2013-08-01

    The fish body is entirely covered by a thin, smooth and glandular epidermis, closely attached to the scales inserted on the dermis. The descriptive work on this tissue dates to twenty or thirty years ago, bears very little photographic record and does not focus on the scale epithelium, despite the fact that it is in direct contact with the environment. Thereupon, the present study characterizes the scale epithelium of Prochilodus lineatus, a robust species of fish. The observations show that the scale is completely covered by epithelium thicker on the proximal end of the scale, multilayered on the dorsal surface and undifferentiated on the ventral surface, and covered by mucous producing cells, mostly acid mucous. The scale is formed by plywood-like collagen matrix of collagen type III and supported by a network of elastic fibers on the ventral face. Differentiated cellular types are present, such as club cells, considered to be responsible for the release of alarm substances, which suggests possible use in environmental assessment as a non-invasive technique. PMID:24212706

  7. Airway epithelium interactions with aeroallergens: role of secreted cytokines and chemokines in innate immunity.

    PubMed

    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

  8. 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.

  9. [Morpho-functional characteristics of the lingual epithelium after administration of hydra peptide morphogen].

    PubMed

    Kulaeva, V V; Bykov, V L

    2007-01-01

    Using histological, morphometric and quantitative histoenzymological methods, the changes of lingual epithelium were studied in 40 outbred albino mice after 5 intraperitoneal injections of 100 micrograms of hydra peptide morphogen (HPM) per 1 kg of body weight. Administration of HPM was found to increase the total thickness of epithelial layer on the dorsal tongue surface in the interpapillary regions, while in the area of filiform papillae these changes were not significant. On the ventral tongue surface HPM induced a marked increase of total thickness of the epithelial layer as compared to that in control animals. Mitotic activity was increased in the epithelium covering the ventral surface and in the interpapillary regions on the dorsal tongue surface. Histoenzymologic study which involved the demonstration of NADH-diaphorase, succinate- and lactate-dehydrogenase (LDH) activities, followed by a cytophotometric evaluation of enzyme activity, has shown a stimulatory effect of HPM on the activity of all the enzymes studied, which was most pronounced in respect to LDH and was maximally expressed on the dorsal tongue surface. These findings collectively suggest that HPM exerts a stimulatory effect on proliferation activity and metabolism of lingual epithelium, which is differentially expressed in its variuoe topographical zones. PMID:17722572

  10. Mesenchymal stem cells for repair of the airway epithelium in asthma.

    PubMed

    Knight, Darryl A; Rossi, Fabio M; Hackett, Tillie-Louise

    2010-12-01

    The airway epithelium is constantly faced with inflammatory and potentially injurious stimuli. Following damage, rapid repair mechanisms involving proliferation and differentiation of resident progenitor and stem cell pools are necessary in order to maintain a protective barrier. In asthma, evidence pointing to a compromised ability of the epithelium to properly repair and regenerate is rapidly accumulating. The consequences of this are presently unknown but are likely to have a significant impact on lung function. Mesenchymal stem cells have the potential to serve as a universal source for replacement of specific cells in several diseases and thus offer hope as a potential therapeutic intervention for the treatment of the chronic remodeling changes that occur in the asthmatic epithelium. However, controversy exists regarding whether these cells can actually home to and engraft within the airways and contribute to tissue function or whether this mechanism is necessary, since they can have potent paracrine immunomodulatory effects. This article focuses on the current knowledge about specific stem cell populations that may contribute to airway epithelial regeneration and discusses the use of mesenchymal stem cells as a potential therapeutic intervention. PMID:21128750

  11. 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

  12. 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

  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. Epithelium-Derived Wnt Ligands Are Essential for Maintenance of Underlying Digit Bone.

    PubMed

    Takeo, Makoto; Hale, Christopher S; Ito, Mayumi

    2016-07-01

    Clinically, many nail disorders accompany bone deformities, but whether the two defects are causally related is under debate. To investigate the potential interactions between the two tissue types, we analyzed epithelial-specific β-catenin-deficient mice, in which nail differentiation is abrogated. These mice showed regression of not only the nail plate but also of the underlying digit bone. Characterization of these bone defects revealed active bone resorption, which is suppressed by Wnt activation in osteoblast and osteoclast precursors. Furthermore, we found that Wntless expression, essential for Wnt ligand secretion, was lacking in the β-catenin-deficient nail epithelium and that genetic deletion of Wntless (Wls) in the nail epithelium led to the lack of Wnt activation in osteoblast and osteoclast precursors and subsequently led to defective regression of the underlying digit bone. Together, these data show that epithelial Wnt ligands can ultimately regulate Wnt signaling in osteoblast and osteoclast precursors, known to regulate bone homeostasis. These results reveal a critical role for the nail epithelium on the digit bone during homeostatic regeneration and show that Wnt/β-catenin signaling is critical for this interaction. PMID:27021406

  15. Hyaluronan distribution in the normal epithelium of esophagus, stomach, and colon and their cancers.

    PubMed Central

    Wang, C.; Tammi, M.; Guo, H.; Tammi, R.

    1996-01-01

    The distribution of hyaluronan (HA) in normal gastrointestinal wall and in tumors originating from their epithelium was studied using a specific probe prepared from cartilage proteoglycan (bHABC, biotinylated hyaluronan binding complex). The normal stratified squamous epithelium of esophagus showed an intense HA staining in the basal and lower intermediate layers, whereas the simple epithelia in the stomach and large intestine were HA negative. Esophageal in situ carcinomas expressed HA also in the cell layers close to the luminal surface, in regions normally negative. Most of the invasive squamous cell carcinomas maintained their HA expression, but in very poorly differentiated types the tumor parenchyma was devoid of HA. In both gastric and colonic adenocarcinomas the tumor parenchyma showed no HA. The stromal tissue was intensely HA positive in all tumors. Cancer cells invading the intestinal smooth muscle were surrounded by copious amounts of HA, whereas the muscular layer was otherwise very poor in HA staining. These results show that relatively well differentiated carcinoma cells themselves retain the high or low HA expression pattern of their original epithelium, whereas tumors stimulate HA deposition in the surrounding stroma. Images Figure 1 Figure 2 Figure 3 PMID:8669472

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

    PubMed

    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; Morrisey, Edward E

    2016-05-01

    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

  17. 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

  18. Bacterial Population Adherent to the Epithelium on the Roo of the Dorsal Rumen of Sheep †

    PubMed Central

    Dehority, Burk A.; Grubb, Jean A.

    1981-01-01

    By anaerobic procedures, the total number of adherent bacteria was determined on tissue samples obtained from the roof of the dorsal rumen of three sheep. After four washings, 1.91 × 107, 0.34 × 107, and 1.23 × 107 bacteria per cm2 were still attached to the rumen epithelium in sheep 1, 2, and 3, respectively. A total of 95 strains of bacteria were isolated from these three samples. Based on morphology, Gram stain, anaerobiosis, motility, and fermentation end products, they were presumptively identified as follows: Butyrivibrio fibrisolvens, 30 strains; atypical Butyrivibrio, 5 strains; Bacteroides ruminicola, 22 strains; Lactobacillus, 1 strain; and unknown Bacteroides species, 37 strains. For sheep 3, washing the rumen epithelium a total of 10 times reduced the adherent bacterial population by 93% (8.4 × 105 bacteria per cm2). Of 30 strains isolated from this sample, 22 were presumptively identified as Butyrivibrio and Bacteroides types. These results suggest that the epithelium on the roof of the dorsal rumen is primarily colonized by two genera of bacteria, Butyrivibrio and Bacteroides. Most Butyrivibrio and Bacteroides ruminicola strains appeared to be similar to previously isolated rumen strains. However, the unknown Bacteroides species differed considerably from the three species of this genus which are commonly isolated from rumen contents. PMID:16345797

  19. 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. PMID:26639494

  20. Specific-sized hyaluronan fragments promote expression of human β-defensin 2 in intestinal epithelium.

    PubMed

    Hill, David R; Kessler, Sean P; Rho, Hyunjin K; Cowman, Mary K; de la Motte, Carol A

    2012-08-31

    Hyaluronan (HA) is a glycosaminoglycan polymer found in the extracellular matrix of virtually all mammalian tissues. Recent work has suggested a role for small, fragmented HA polymers in initiating innate defense responses in immune cells, endothelium, and epidermis through interaction with innate molecular pattern recognition receptors, such as TLR4. Despite these advances, little is known regarding the effect of fragmented HA at the intestinal epithelium, where numerous pattern recognition receptors act as sentinels of an innate defense response that maintains epithelial barrier integrity in the presence of abundant and diverse microbial challenges. Here we report that HA fragments promote expression of the innate antimicrobial peptide human β-defensin 2 (HβD2) in intestinal epithelial cells. Treatment of HT-29 colonic epithelial cells with HA fragment preparations resulted in time- and dose-dependent up-regulated expression of HβD2 protein in a fragment size-specific manner, with 35-kDa HA fragment preparations emerging as the most potent inducers of intracellular HβD2. Furthermore, oral administration of specific-sized HA fragments promotes the expression of an HβD2 ortholog in the colonic epithelium of both wild-type and CD44-deficient mice but not in TLR4-deficient mice. Together, our observations suggest that a highly size-specific, TLR4-dependent, innate defense response to fragmented HA contributes to intestinal epithelium barrier defense through the induction of intracellular HβD2 protein. PMID:22761444

  1. Apoptosis, necrosis and necroptosis: cell death regulation in the intestinal epithelium.

    PubMed

    Günther, Claudia; Neumann, Helmut; Neurath, Markus F; Becker, Christoph

    2013-07-01

    Intestinal epithelial cells (IEC) are organised as a single cell layer which covers the intestine. Their primary task is to absorb nutrients present in the intestinal lumen. However, IEC also play an important role in the immune defence of our body by building a barrier that separates the bowel wall from potentially hazardous bacteria present in the gut lumen. The life cycle of IEC is determined by the time span in which cells migrate from their place of origin at the crypt base to the villus tip, from where they are shed into the lumen. Cell death in the intestinal epithelium has to be tightly regulated and irregularities might cause pathologies. Excessive cell death has been associated with chronic inflammation as seen in patients with Crohn's disease and ulcerative colitis. While until recently apoptosis was discussed as being essential for epithelial turnover and tissue homeostasis in the intestinal epithelium, recent data using gene deficient mice have challenged this concept. Moreover, an apoptosis-independent mode of programmed cell death, termed necroptosis, has been identified and described in the intestinal epithelium. The following article reviews previous studies on cell death regulation in IEC and a potential role of necroptosis for gut homeostasis. PMID:22689519

  2. Effects of oral contraceptive pill use on vaginal flora and vaginal epithelium.

    PubMed

    Eschenbach, D A; Patton, D L; Meier, A; Thwin, S S; Aura, J; Stapleton, A; Hooton, T M

    2000-09-01

    The objective of this study was to examine the effect of oral contraceptive (OC) use on vaginal discharge, epithelium, and flora. Thirty women who planned to use OC for contraception were evaluated before and 2 months after the start of OC use. At both visits, genital symptoms and exposures were assessed by questionnaire; vaginal signs were assessed by speculum examination and colposcopy; vaginal microflora was evaluated by quantitative culture; and a vaginal biopsy was obtained for histopathologic evaluation. Variables were compared between the initial visit and after 2 months of OC use. It was found that OC use did not change the gross, colposcopic, or histologic appearance of the vaginal epithelium or characteristics of vaginal or cervical discharge. Vaginal flora essentially remained unchanged after 2 months of OC use, except that a small decrease occurred in the number of subjects with > or =10(5) colony forming units/mL of H(2)O(2) producing Lactobacillus from 16 at baseline to 9 (p = 0.04) and in the total number of subjects with Ureaplasma urealyticum from 17 at baseline to 10 of 29 (p = 0.04). The results indicate minimal effect of OC use on the vaginal epithelium and vaginal and cervical discharge, and a small effect on vaginal flora. PMID:11124356

  3. 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

  4. 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...

  5. Histology of the pouch epithelium and the mammary glands during chemically induced oestrus in the brushtail possum (Trichosurus vulpecula)

    PubMed Central

    Old, Julie M; Irving, M; Deane, Elizabeth M

    2005-01-01

    Changes in the epithelium of the maternal pouch and the mammary gland of brushtail possums (Trichosurus vulpecula) were examined after animals were treated to induce ovulation with follicle-stimulating hormone (FSH), luteinizing hormone (LH), pregnant mares’ serum gonadotrophin (PMSG) and oestradiol. The mammary glands were similar in appearance to those described in eutherian mammals and in previous studies on other marsupials. Exposure of possums to these compounds, particularly PSMG, appeared to result in changes in the mammary glands that could be associated with milk/secretion production. In contrast, the pouch epithelium had a similar histological appearance to that of epithelium from other parts of the body regardless of whether the animal was exposed to stimulants. These preliminary observations are discussed in the context of the purported role of the pouch epithelium and the mammary gland in production of secretions at oestrus and provision of immunological protection to the neonatal marsupial. PMID:16011549

  6. 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

  7. 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

  8. Comparison of Expression Profiles in Ovarian Epithelium In Vivo and Ovarian Cancer Identifies Novel Candidate Genes Involved in Disease Pathogenesis

    PubMed Central

    Emmanuel, Catherine; Gava, Natalie; Kennedy, Catherine; Balleine, Rosemary L.; Sharma, Raghwa; Wain, Gerard; Brand, Alison; Hogg, Russell; Etemadmoghadam, Dariush; George, Joshy; Birrer, Michael J.; Clarke, Christine L.; Chenevix-Trench, Georgia; Bowtell, David D. L.; Harnett, Paul R.; deFazio, Anna

    2011-01-01

    Molecular events leading to epithelial ovarian cancer are poorly understood but ovulatory hormones and a high number of life-time ovulations with concomitant proliferation, apoptosis, and inflammation, increases risk. We identified genes that are regulated during the estrous cycle in murine ovarian surface epithelium and analysed these profiles to identify genes dysregulated in human ovarian cancer, using publically available datasets. We identified 338 genes that are regulated in murine ovarian surface epithelium during the estrous cycle and dysregulated in ovarian cancer. Six of seven candidates selected for immunohistochemical validation were expressed in serous ovarian cancer, inclusion cysts, ovarian surface epithelium and in fallopian tube epithelium. Most were overexpressed in ovarian cancer compared with ovarian surface epithelium and/or inclusion cysts (EpCAM, EZH2, BIRC5) although BIRC5 and EZH2 were expressed as highly in fallopian tube epithelium as in ovarian cancer. We prioritised the 338 genes for those likely to be important for ovarian cancer development by in silico analyses of copy number aberration and mutation using publically available datasets and identified genes with established roles in ovarian cancer as well as novel genes for which we have evidence for involvement in ovarian cancer. Chromosome segregation emerged as an important process in which genes from our list of 338 were over-represented including two (BUB1, NCAPD2) for which there is evidence of amplification and mutation. NUAK2, upregulated in ovarian surface epithelium in proestrus and predicted to have a driver mutation in ovarian cancer, was examined in a larger cohort of serous ovarian cancer where patients with lower NUAK2 expression had shorter overall survival. In conclusion, defining genes that are activated in normal epithelium in the course of ovulation that are also dysregulated in cancer has identified a number of pathways and novel candidate genes that may contribute

  9. Impact of detergents on the protein histochemistry of various cell types of the gill epithelium of Rita rita.

    PubMed

    Roy, D

    1988-04-01

    Fish, Rita rita, were exposed to an anionic detergent, dodecylbenzene sodium sulfonate, 6.9 mg per litre of tap water (96-hr LC50 of the detergent). A gradual decrease in the protein constituents of the major cell types, viz, the epithelial cells and the goblet mucous cells in the epithelium lining the gill arch, gill filament, and club cells present only in the gill arch epithelium has been observed by using a series of histochemical techniques. PMID:3378537

  10. 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

  11. 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

  12. Morphogenesis and cytodifferentiation of the avian retinal pigmented epithelium require downregulation of Group B1 Sox genes

    PubMed Central

    Ishii, Yasuo; Weinberg, Kerry; Oda-Ishii, Izumi; Coughlin, Laura; Mikawa, Takashi

    2009-01-01

    Summary The optic vesicle is a multipotential primordium of the retina, which becomes subdivided into the neural retina and retinal pigmented epithelium domains. Although the roles of several paracrine factors in patterning the optic vesicle have been studied extensively, little is known about cell-autonomous mechanisms that regulate coordinated cell morphogenesis and cytodifferentiation of the retinal pigmented epithelium. Here we demonstrate that members of the SoxB1 gene family, Sox1, Sox2 and Sox3, are all downregulated in the presumptive retinal pigmented epithelium. Constitutive maintenance of SoxB1 expression in the presumptive retinal pigmented epithelium both in vivo and in vitro resulted in the absence of cuboidal morphology and pigmentation, and in concomitant induction of neural differentiation markers. We also demonstrate that exogenous Fgf4 inhibits downregulation all SoxB1 family members in the presumptive retinal pigment epithelium. These results suggest that retinal pigment epithelium morphogenesis and cytodifferentiation requires SoxB1 downregulation, which depends on the absence of exposure to an FGF-like signal. PMID:19570849

  13. MicroRNA Expression Profiles of Human iPS Cells, Retinal Pigment Epithelium Derived From iPS, and Fetal Retinal Pigment Epithelium

    PubMed Central

    Greene, Whitney A.; Muñiz, Alberto.; Plamper, Mark L.; Kaini, Ramesh R.; Wang, Heuy-Ching

    2014-01-01

    The objective of this report is to describe the protocols for comparing the microRNA (miRNA) profiles of human induced-pluripotent stem (iPS) cells, retinal pigment epithelium (RPE) derived from human iPS cells (iPS-RPE), and fetal RPE. The protocols include collection of RNA for analysis by microarray, and the analysis of microarray data to identify miRNAs that are differentially expressed among three cell types. The methods for culture of iPS cells and fetal RPE are explained. The protocol used for differentiation of RPE from human iPS is also described. The RNA extraction technique we describe was selected to allow maximal recovery of very small RNA for use in a miRNA microarray. Finally, cellular pathway and network analysis of microarray data is explained. These techniques will facilitate the comparison of the miRNA profiles of three different cell types. PMID:24999033

  14. Innate Immune Response to LPS in Airway Epithelium Is Dependent on Chronological Age and Antecedent Exposures

    PubMed Central

    Maniar-Hew, Kinjal; Clay, Candice C.; Postlethwait, Edward M.; Evans, Michael J.; Fontaine, Justin H.

    2013-01-01

    The immune mechanisms for neonatal susceptibility to respiratory pathogens are poorly understood. Given that mucosal surfaces serve as a first line of host defense, we hypothesized that the innate immune response to infectious agents may be developmentally regulated in airway epithelium. To test this hypothesis, we determined whether the expression of IL-8 and IL-6 in airway epithelium after LPS exposure is dependent on chronological age. Tracheas from infant, juvenile, and adult rhesus monkeys were first exposed to LPS ex vivo, and then processed for air–liquid interface primary airway epithelial cell cultures and secondary LPS treatment in vitro. Compared with adult cultures, infant and juvenile cultures expressed significantly reduced concentrations of IL-8 after LPS treatment. IL-8 protein in cultures increased with animal age, whereas LPS-induced IL-6 protein was predominantly associated with juvenile cultures. Toll-like receptor (TLR) pathway RT-PCR arrays showed differential expressions of multiple mRNAs in infant cultures relative to adult cultures, including IL-1α, TLR10, and the peptidoglycan recognition protein PGLYRP2. To determine whether the age-dependent cytokine response to LPS is reflective of antecedent exposures, we assessed primary airway epithelial cell cultures established from juvenile monkeys housed in filtered air since birth. Filtered air–housed animal cultures exhibited LPS-induced IL-8 and IL-6 expression that was discordant with age-matched ambient air–housed animals. A single LPS aerosol in vivo also affected this cytokine profile. Cumulatively, our findings demonstrate that the innate immune response to LPS in airway epithelium is variable with age, and may be modulated by previous environmental exposures. PMID:23600597

  15. Impact of the Metabolic Activity of Streptococcus thermophilus on the Colon Epithelium of Gnotobiotic Rats*

    PubMed Central

    Rul, Françoise; Ben-Yahia, Leila; Chegdani, Fatima; Wrzosek, Laura; Thomas, Stéphane; Noordine, Marie-Louise; Gitton, Christophe; Cherbuy, Claire; Langella, Philippe; Thomas, Muriel

    2011-01-01

    The thermophilic lactic acid bacterium Streptococcus thermophilus is widely and traditionally used in the dairy industry. Despite the vast level of consumption of S. thermophilus through yogurt or probiotic functional food, very few data are available about its physiology in the gastrointestinal tract (GIT). The objective of the present work was to explore both the metabolic activity and host response of S. thermophilus in vivo. Our study profiles the protein expression of S. thermophilus after its adaptation to the GIT of gnotobiotic rats and describes the impact of S. thermophilus colonization on the colonic epithelium. S. thermophilus colonized progressively the GIT of germ-free rats to reach a stable population in 30 days (108 cfu/g of feces). This progressive colonization suggested that S. thermophilus undergoes an adaptation process within GIT. Indeed, we showed that the main response of S. thermophilus in the rat's GIT was the massive induction of the glycolysis pathway, leading to formation of lactate in the cecum. At the level of the colonic epithelium, the abundance of monocarboxylic acid transporter mRNAs (SLC16A1 and SLC5A8) and a protein involved in the cell cycle arrest (p27kip1) increased in the presence of S. thermophilus compared with germ-free rats. Based on different mono-associated rats harboring two different strains of S. thermophilus (LMD-9 or LMG18311) or weak lactate-producing commensal bacteria (Bacteroides thetaiotaomicron and Ruminococcus gnavus), we propose that lactate could be a signal produced by S. thermophilus and modulating the colon epithelium. PMID:21239485

  16. [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

  17. Early survival factor deprivation in the olfactory epithelium enhances activity-driven survival.

    PubMed

    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

  18. 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

  19. AGEs Promote Oxidative Stress and Induce Apoptosis in Retinal Pigmented Epithelium Cells RAGE-dependently.

    PubMed

    Wang, Xin-Ling; Yu, Tao; Yan, Qi-Chang; Wang, Wei; Meng, Nan; Li, Xue-Jiao; Luo, Ya-Hong

    2015-06-01

    Advanced glycation end products (AGEs) are extremely accumulated in diabetes mellitus, particularly in retinal vascular and epithelium cells, and are confirmed to contribute to diabetic retinopathy (DR). In the present study, we determined the promotion by AGEs to the oxidative stress and mitochondrial dysfunction in retinal pigmented epithelium ARPE-19 cells and investigated the influence by the knockdown or the overexpression of receptor for AGEs (RAGE) on the AGE-promoted oxidative stress and mitochondrial dysfunction. Furthermore, we determined the induction by AGEs to the cell apoptosis and to the activation of B-cell lymphoma 2 (Bcl-2) families in the AGE-BSA-induced apoptosis, and examined the RAGE-dependence in such induction. Results demonstrated that AGE-BSA upregulated the hydrogen peroxide production and induced mitochondrial dysfunction in ARPE-19 cells, dose-dependently. And the further investigation indicated that the AGE-RAGE interaction was required for the induction of oxidative stress and mitochondrial dysfunction. Moreover, the AGE-BSA treatment promoted a significantly high level of apoptotic cells, and the Bcl-2 family was implicated in the AGE-BSA-induced apoptosis, there was a significant high level of Cyt c release, Bcl-2-associated X protein (Bax) induction, Bcl-2 reduction, and caspase 9 activation in the AGE-BSA-treated cells. In conclusion, the present study recognized the apoptosis induction by AGE-BSAs in the retinal epithelium ARPE-19 cells, RAGE-dependently. The mitochondrial dysfunction was induced, and the Bcl-2 family was deregulated during the AGE-BSA-induced ARPE-19 cell apoptosis. PMID:25682235

  20. Immunohistochemical and hybridocytochemical study on ghrelin signalling in the rat seminiferous epithelium.

    PubMed

    Łukaszyk, Andrzej; Rafińska, Ludmiła; Sawiński, Piotr; Kasprzak, Aldona; Olejniczak, Karolina; Ruciński, Marcin; Ruchała, Marek; Sowiński, Jerzy

    2009-01-01

    The results of presented study demonstrate expression of ghrelin, its functional receptor GHSR-1a and their genes in spermatogenic cells of rat testis suggesting their functioning within seminiferous epithelium. The immunohistochemical and hybrydocytochemical expression, of proteins and transcripts, was estimated taking into account the cycle of seminiferous epithelium and phases of spermatogenesis. Both transcripts and ghrelin was found to show nuclear expression and scarcely cytoplasmic. Expression of genes for ghrelin and GHSR-1a was shown in early spermatocytes and round spermatids representing transcriptional phases of meiosis and spermiogenesis. Ghrelin was evidenced to show nuclear expression in two stage-specific windows, in late spermatogonia, in spermatocytes up to early pachytenes, and again in spermatids of acrosome and early maturation phase of spermiogenesis. In late pachytenes, secondary spermatocytes, round spermatids, maturing spermatids and spermatozoa the reaction is lacking. With two types of antibodies against the GHSR-1a used the two different patterns of immunostaining was evidenced suggesting two isoforms of GHSR-1a. The first evidenced GHSR-1a in cytoplasm of spermatocytes, cell membrane and acrosomes of spermatids, Sertoli cell processes and heads of spermatozoa. With second type of antibodies the immunostaining marks all steps of evolution of acrosome in spermatids. It is believed that site of ghrelin expression in seminiferous epithelium may indicate its role in local regulations, not excepting the intracellular signalling. Immunostaining pattern for GHSR-1a seems to suggest both its participation in the cross-talk among the cells and also process of furnishing gametes with GHSR-1a for its response to ghrelin in seminal plasma or female reproductive tract. PMID:20164026

  1. Loss of Rab27 function results in abnormal lung epithelium structure in mice

    PubMed Central

    Bolasco, Giulia; Tracey-White, Dhani C.; Tolmachova, Tanya; Thorley, Andrew J.; Tetley, Teresa D.; Seabra, Miguel C.

    2011-01-01

    Rab27 small GTPases regulate secretion and movement of lysosome-related organelles such as T cell cytolytic granules and platelet-dense granules. Previous studies indicated that Rab27a and Rab27b are expressed in the murine lung suggesting that they regulate secretory processes in the lung. Consistent with those studies, we found that Rab27a and Rab27b are expressed in cell types that contain secretory granules: alveolar epithelial type II (AEII) and Clara cells. We then used Rab27a/Rab27b double knockout (DKO) mice to examine the functional consequence of loss of Rab27 proteins in the murine lung. Light and electron microscopy revealed a number of morphological changes in lungs from DKO mice when compared with those in control animals. In aged DKO mice we observed atrophy of the bronchiolar and alveolar epithelium with reduction of cells numbers, thinning of the bronchiolar epithelium and alveolar walls, and enlargement of alveolar airspaces. In these samples we also observed increased numbers of activated foamy alveolar macrophages and granulocyte containing infiltrates together with reduction in the numbers of Clara cells and AEII cells compared with control. At the ultrastructural level we observed accumulation of cytoplasmic membranes and vesicles in Clara cells. Meanwhile, AEII cells in DKO accumulated large mature lamellar bodies and lacked immature/precursor lamellar bodies. We hypothesize that the morphological changes observed at the ultrastructural level in DKO samples result from secretory defects in AEII and Clara cells and that over time these defects lead to atrophy of the epithelium. PMID:21160031

  2. 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

  3. An intracellular trafficking pathway in the seminiferous epithelium regulating spermatogenesis: A biochemical and molecular perspective*

    PubMed Central

    Cheng, C. Yan; Mruk, Dolores D.

    2009-01-01

    During spermatogenesis, fully developed spermatids (i.e., spermatozoa) at the luminal edge of the seminiferous epithelium undergo ‘spermiation’ at stage VIII of the seminiferous epithelial cycle. This is manifested by the disruption of the apical ectoplasmic specialization (apical ES) so that spermatozoa can enter the tubule lumen and to complete their maturation in the epididymis. At the same time, the blood-testis barrier (BTB) located near the basement membrane undergoes extensive restructuring to allow transit of preleptotene spermatocytes so that post-meiotic germ cells complete their development behind the BTB. While spermiation and BTB restructuring take place concurrently at opposite ends of the Sertoli cell epithelium, the biochemical mechanism(s) by which they are coordinated were not known until recently. Studies have shown that fragments of laminin chains are generated from the laminin/integrin protein complex at the apical ES via the action of MMP-2 (matrix metalloprotease-2) at spermiation. These peptides serve as the local autocrine factors to ‘destabilize’ the BTB. These laminin peptides also exert their effects on hemidesmosome which, in turn, further potentiates BTB restructuring. Thus, a novel apical ES-BTB-hemidesmosome regulatory loop is operating in the seminiferous epithelium to coordinate these two crucial cellular events of spermatogenesis. This functional loop is further assisted by the Par3/Par6-based polarity protein complex in coordination with cytokines and testosterone at the BTB. Herein, we provide a critical review based on the latest findings in the field regarding the regulation of these cellular events. These recent findings also open up a new window for investigators studying blood-tissue barriers. PMID:19622063

  4. Epithelium integrity is crucial for the relaxant activity of brain natriuretic peptide in human isolated bronchi

    PubMed Central

    Matera, Maria G; Calzetta, Luigino; Passeri, Daniela; Facciolo, Francesco; Rendina, Erino A; Page, Clive; Cazzola, Mario; Orlandi, Augusto

    2011-01-01

    BACKGROUND AND PURPOSE Brain natriuretic peptide (BNP) plays an important role in several biological functions, including bronchial relaxation. Here, we have investigated the role of BNP and its cognate receptors in human bronchial tone. EXPERIMENTAL APPROACH Effects of BNP on responses to carbachol and histamine were evaluated in non-sensitized, passively sensitized, epithelium-intact or denuded isolated bronchi and in the presence of methoctramine, Nω-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine. Natriuretic peptide receptors (NPRs) were investigated by immunohistochemistry, RT-PCR and real-time PCR. Release of NO and acetylcholine from bronchial tissues and cultured BEAS-2B bronchial epithelial cells was also investigated. KEY RESULTS BNP reduced contractions mediated by carbachol and histamine, with decreased Emax (carbachol: 22.7 ± 4.7%; histamine: 59.3 ± 1.8%) and increased EC50 (carbachol: control 3.33 ± 0.88 µM, BNP 100 ± 52.9 µM; histamine: control 16.7 ± 1.7 µM, BNP 90 ± 30.6 µM); BNP was ineffective in epithelium-denuded bronchi. Among NPRs, only atrial NPR (NPR1) transcripts were detected in bronchial tissue. Bronchial NPR1 immunoreactivity was detected in epithelium and inflammatory cells but faint or absent in airway smooth muscle cells. NPR1 transcripts in bronchi increased after incubation with BNP, but not after sensitization. Methoctramine and quinine abolished BNP-induced relaxant activity. The latter was associated with increased bronchial mRNA for NO synthase and NO release, inhibited by L-NAME and aminoguanidine. In vitro, BNP increased acetylcholine release from bronchial epithelial cells, whereas NO release was unchanged. CONCLUSIONS AND IMPLICATIONS Epithelial cells mediate the BNP-induced relaxant activity in human isolated bronchi. PMID:21410689

  5. 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

  6. Cyclin dependent kinase inhibitor p27Kip1 expression in normal and neoplastic cervical epithelium.

    PubMed Central

    Troncone, G; Vetrani, A; de Rosa, G; Gerbasio, D; Palombini, L

    1999-01-01

    AIM: To investigate whether there is loss of the p27Kip1 protein in developing cervical cancer and whether p27Kip1 immunoreactivity has any relation to the proliferative indicator Ki-67. METHODS: The expression of p27Kip1 and Ki-67 was assessed by immunohistochemistry in serial sections from normal epithelium (13), low grade (27) and high grade (19) squamous intraepithelial lesions (LSIL, HSIL), and invasive cervical cancer (23). In the SIL cases the presence of human papillomavirus (HPV) genomic sequences was assessed by in situ hybridisation. The results were evaluated by image analysis, and reported as mean score of the percentage of p27Kip1 and of Ki-67 positive cells in each histological group. RESULTS: In general, p27Kip1 immunostaining was related to squamous differentation, and was intense in normal epithelium (47%), while it was reduced in SIL lesions as an effect of the decreased number of differentiating cells. However, decrease in the p27Kip1 expression was more evident in LSIL (36%) than in HSIL (39%); in the latter, p27Kip1 had a different intraepithelial distribution in that the staining extended to the basal cells. The average levels of p27Kip1 were similar in SIL lesions associated to low, intermediate, and high risk HPV types. Compared with normal epithelium and dysplasia, invasive cancer showed significantly lower p27Kip1 levels (23%). There was no relation between p27Kip1 and Ki-67 labelling indices in any of the histological groups examined. CONCLUSIONS: A reduction in p27Kip1 protein occurs in cervical cancer independently of the proliferative status. The changes in p27Kip1 expression may be related to the unregulated kinetics of developing cervical cancer. Images PMID:10711250

  7. 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

  8. Biological activity of celecoxib in the bronchial epithelium of current and former smokers.

    PubMed

    Kim, Edward S; Hong, Waun K; Lee, J Jack; Mao, Li; Morice, Rodolfo C; Liu, Diane D; Jimenez, Carlos A; Eapen, Georgie A; Lotan, Reuben; Tang, Ximing; Newman, Robert A; Wistuba, Ignacio I; Kurie, Jonathan M

    2010-02-01

    Non-small cell lung cancer is the primary cause of cancer-related death in Western countries. One important approach taken to address this problem is the development of effective chemoprevention strategies. In this study, we examined whether the cyclooxygenase-2 inhibitor celecoxib, as evidenced by decreased cell proliferation, is biologically active in the bronchial epithelium of current and former smokers. Current or former smokers with at least a 20 pack-year (pack-year = number of packs of cigarettes per day times number of years smoked) smoking history were randomized into one of four treatment arms (3-month intervals of celecoxib then placebo, celecoxib then celecoxib, placebo then celecoxib, or placebo then placebo) and underwent bronchoscopies with biopsies at baseline, 3 months, and 6 months. The 204 patients were primarily (79.4%) current smokers: 81 received either low-dose celecoxib or placebo and 123 received either high-dose celecoxib or placebo. Celecoxib was originally administered orally at 200 mg twice daily and the protocol subsequently increased the dose to 400 mg twice daily. The primary end point was change in Ki-67 labeling (from baseline to 3 months) in bronchial epithelium. No cardiac toxicities were observed in the participants. Although the effect of low-dose treatment was not significant, high-dose celecoxib decreased Ki-67 labeling by 3.85% in former smokers and by 1.10% in current smokers-a significantly greater reduction (P = 0.02) than that seen with placebo after adjusting for metaplasia and smoking status. A 3- to 6-month celecoxib regimen proved safe to administer. Celecoxib (400 mg twice daily) was biologically active in the bronchial epithelium of current and former smokers; additional studies on the efficacy of celecoxib in non-small cell lung cancer chemoprevention may be warranted. PMID:20103722

  9. Critical role of p63 in the development of a normal esophageal and tracheobronchial epithelium.

    PubMed

    Daniely, Yaron; Liao, Grace; Dixon, Darlene; Linnoila, R Ilona; Lori, Adriana; Randell, Scott H; Oren, Moshe; Jetten, Anton M

    2004-07-01

    The trachea and esophagus originate from the foregut endoderm during early embryonic development. Their epithelia undergo a series of changes involving the differentiation of stem cells into unique cell types and ultimately forming the mature epithelia. In this study, we monitored the expression of p63 in the esophagus and the trachea during development and examined in detail morphogenesis in p63(-/-) mice. At embryonic day 15.5 (E15.5), the esophageal and tracheobronchial epithelia contain two to three layers of cells; however, only the progenitor cells express p63. These progenitor cells differentiate first into ciliated cells (p63(-)/beta-tubulin IV(+)) and after birth into mature basal cells (p63(+)/K14(+)/K5(+)/BS-I-B4(+)). In the adult pseudostratified, columnar tracheal epithelium, K14(+)/K5(+)/BS-I-B4(+) basal cells stain most intensely for p63, whereas ciliated and mucosecretory cells are negative. In stratified squamous esophageal epithelium and during squamous metaplasia in the trachea, cells in the basal layer stain strongest for p63, whereas p63 staining declines progressively in transient amplifying and squamous differentiated cells. Generally, p63 expression is restricted to human squamous cell carcinomas, and adenocarcinomas and Barrett's metaplasia do not stain for p63. Examination of morphogenesis in newborn p63(-/-) mice showed an abnormal persistence of ciliated cells in the esophagus. Significantly, in both tissues, lack of p63 expression results in the development of a highly ordered, columnar ciliated epithelium deficient in basal cells. These observations indicate that p63 plays a critical role in the development of normal esophageal and tracheobronchial epithelia and appears to control the commitment of early stem cells into basal cell progeny and the maintenance of basal cells. PMID:15189821

  10. 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.

  11. Secretion and electrogenesis of the supporting cell in the olfactory epithelium

    PubMed Central

    Okano, Masaomi; Takagi, Sadayuki F.

    1974-01-01

    1. Electrophysiological study disclosed that chloroform and some other odours generate long-lasting positive potentials in the olfactory epithelium of the bullfrog, while electron microscopical study showed that they elicit vigorous protrusion of the distal cytoplasmic portion of the supporting cell containing the secretory granules. 2. The secretory process of the supporting cell is as follows: The first detectable indication is the protrusion of the apical portion of the supporting cell (Pls. 3 and 4); the protruded part detaches from its maternal supporting cell (Pl. 7 B), floats as a droplet in the mucus (Pl. 5), and finally the secretory granules inside the droplet disintegrate into the mucus (Pls. 6 and 7 A). 3. The secretion was not elicited by the odours which elicit the negative potentials. 4. In Cl--free Ringer solution, neither the positive potential nor the protrusion and secretion occurred. 5. When 1-2 mM-Ba2+ in Ringer solution was dripped on the epithelium, both the positive potential and the protrusion and secretion resulted. Subsequent application of chloroform vapour only advanced further disintegration of the secretory granules, but it elicited neither a new protrusion of the granules nor the positive potential. 6. In the olfactory epithelium in which the olfactory cells had degenerated but the supporting cells survived, both the positive potential and the protrusion and secretion occurred, but the negative potential did not. 7. It is concluded that Cl- entry which mainly generates the longlasting positive potential triggers the secretion of the supporting cell. ImagesABPlate 5Plate 6ABPlate 8ABABABAB PMID:4549073

  12. 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

  13. 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

  14. 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

  15. Chemosensory Brush Cells of the Trachea. A Stable Population in a Dynamic Epithelium

    PubMed Central

    Reynolds, Susan D.; Finger, Thomas E.

    2013-01-01

    Tracheal brush cells (BCs) are specialized epithelial chemosensors that use the canonical taste transduction cascade to detect irritants. To test whether BCs are replaced at the same rate as other cells in the surrounding epithelium of adult mice, we used 5-bromo-2′-deoxyuridine (BrdU) to label dividing cells. Although scattered BrdU-labeled epithelial cells are present 5–20 days after BrdU, no BCs are labeled. These data indicate that BCs comprise a relatively static population. To determine how BCs are generated during development, we injected 5-day-old mice with BrdU and found labeled BCs and non-BC epithelial cells 5 days after BrdU. During the next 60 days, the percentage of labeled BCs increased, whereas the percentage of other labeled cell types decreased. These data suggest that BCs are generated from non-BC progenitor cells during postnatal tracheal growth. To test whether the adult epithelium retains the capacity to generate BCs, tracheal epithelial cells were recovered from adult mice and grown in an air–liquid interface (ALI) culture. After transition to differentiation conditions, BCs are detected, and comprise 1% of the total cell population by Day 14. BrdU added to cultures before the differentiation of BCs was chased into BCs, indicating that the increase in BC density is attributable to the proliferation of a non-BC progenitor. We conclude that: (1) BCs are normally a static population in adult mice; (2) BC progenitors proliferate and differentiate during neonatal development; and (3) BCs can be regenerated from a proliferative population resident in adult epithelium. PMID:23526223

  16. Current smoking-specific gene expression signature in normal bronchial epithelium is enhanced in squamous cell lung cancer.

    PubMed

    Boelens, Mirjam C; van den Berg, Anke; Fehrmann, Rudolf S N; Geerlings, Marie; de Jong, Wouter K; te Meerman, Gerard J; Sietsma, Hannie; Timens, Wim; Postma, Dirkje S; Groen, Harry J M

    2009-06-01

    Cigarette smoking is the main risk factor for the development of squamous cell lung carcinoma (SCC). However, the smoking-related molecular changes in SCC have not been studied. Gene expression studies in both histologically normal bronchial epithelium and SCC epithelial samples identified genes differentially expressed between current and ex-smokers. Subsequently, expression levels of the smoking-related genes in normal bronchial epithelium were compared with those in SCC cells, since we hypothesized that the smoking-induced changes would be also deregulated in SCC. Gene expression profiles were generated using Agilent whole human genome microarrays on laser-microdissected normal bronchial epithelium and SCC samples. Expression levels of 246 genes, mainly related to oxidative stress response, were significantly different between normal bronchial epithelium of current and ex-smokers. Such a differential gene expression profile did not exist in SCC cells of smokers and ex-smokers. Interestingly, when comparing SCC and normal bronchial epithelium from ex-smokers, the vast majority of these 246 genes were also deregulated in SCC. When comparing SCC with normal epithelium from smokers, 22% of the up-regulated genes showed a similar high expression in SCC whereas 79% of the down-regulated genes were even further reduced in SCC as compared to current smokers. The down-regulated genes included several tumour suppressor genes, such as C9orf9, INHBB, LRIG1, SCGB3A1, SERPINI2, STEAP3 and ZMYND10. Thus, our study shows that the majority of genes up-regulated in normal bronchial epithelium of current smokers show similar high expression levels in SCC, while down-regulated genes are even further repressed in SCC. Our data indicate that smoking-related changes in normal bronchial epithelial cells persist in malignant transformed squamous cells. PMID:19334046

  17. 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

  18. 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

  19. Bronchial epithelial spheroids: an alternative culture model to investigate epithelium inflammation-mediated COPD

    PubMed Central

    Deslee, Gaetan; Dury, Sandra; Perotin, Jeanne M; Al Alam, Denise; Vitry, Fabien; Boxio, Rachel; Gangloff, Sophie C; Guenounou, Moncef; Lebargy, François; Belaaouaj, Abderrazzaq

    2007-01-01

    Background Chronic obstructive pulmonary disease (COPD) is characterized by abnormal lung inflammation that exceeds the protective response. Various culture models using epithelial cell lines or primary cells have been used to investigate the contribution of bronchial epithelium in the exaggerated inflammation of COPD. However, these models do not mimic in vivo situations for several reasons (e.g, transformed epithelial cells, protease-mediated dissociation of primary cells, etc.). To circumvent these concerns, we developed a new epithelial cell culture model. Methods Using non transformed non dissociated bronchial epithelium obtained by bronchial brushings from COPD and non-COPD smokers, we developed a 3-dimensional culture model, bronchial epithelial spheroids (BES). BES were analyzed by videomicroscopy, light microscopy, immunofluorescence, and transmission electron microscopy. We also compared the inflammatory responses of COPD and non-COPD BES. In our study, we chose to stimulate BES with lipopolycaccharide (LPS) and measured the release of the pro-inflammatory mediators interleukin-8 (IL-8) and leukotriene B4 (LTB4) and the anti-inflammatory mediator prostaglandin E2 (PGE2). Results BES obtained from both COPD and non-COPD patients were characterized by a polarized bronchial epithelium with tight junctions and ciliary beating, composed of basal cells, secretory cells and ciliated cells. The ciliary beat frequency of ciliated cells was not significantly different between the two groups. Of interest, BES retained their characteristic features in culture up to 8 days. BES released the inflammatory mediators IL-8, PGE2 and LTB4 constitutively and following exposure to LPS. Interestingly, LPS induced a higher release of IL-8, but not PGE2 and LTB4 in COPD BES (p < 0.001) which correlated with lung function changes. Conclusion This study provides for the first time a compelling evidence that the BES model provides an unaltered bronchial surface epithelium. More

  20. 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

  1. Healing velocity of corneal epithelium evaluated by computer. The effect of topical steroid.

    PubMed

    Rask, R; Jensen, P K; Ehlers, N

    1995-04-01

    To objective determine the area of corneal abrasion, a video camera was connected to a slit-lamp. The videosignal was digitized and analyzed by a computer program. The maximal horizontal and vertical diameters were measured as well as the total abraded area. The algorithms of calculating healing velocity of corneal epithelium are discussed, and this system was tested on patients treated for myopia with a 193 nm ArF excimer laser. It was shown that topical steroid application did not impair corneal epithelial healing velocity. PMID:7656147

  2. HIV Impairs Lung Epithelial Integrity and Enters the Epithelium to Promote Chronic Lung Inflammation

    PubMed Central

    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.

    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

  3. 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

  4. Collagenase-3 (matrix metalloproteinase-13) expression is induced in oral mucosal epithelium during chronic inflammation.

    PubMed Central

    Uitto, V. J.; Airola, K.; Vaalamo, M.; Johansson, N.; Putnins, E. E.; Firth, J. D.; Salonen, J.; López-Otín, C.; Saarialho-Kere, U.; Kähäri, V. M.

    1998-01-01

    Increased proliferation of mucosal epithelium during inflammation is associated with degradation of subepithelial connective tissue matrix and local invasion of the epithelial cells. Here we have studied, whether collagenase-3 (MMP-13), a collagenolytic matrix metalloproteinase with an exceptionally wide substrate specificity, is expressed in the epithelium of chronically inflamed mucosa. Examination of human gingival tissue sections from subjects with chronic adult periodontitis with in situ hybridization revealed marked expression of MMP-13 in basal cells of some epithelial rete ridges expanding into connective tissue. Immunohistochemical staining demonstrated that these cells also expressed strongly laminin-5, suggesting that they are actively migrating cells. A strong signal for MMP-13 mRNA was occasionally also noted in the suprabasal epithelial cells facing the gingival pocket, whereas no collagenase-1 (MMP-1) mRNA was detected in any areas of the epithelium. MMP-13 expression was also detected in fibroblast-like cells associated with collagen fibers of the inflamed subepithelial connective tissue. In organ culture of human oral mucosa, MMP-13 mRNA expression was observed in epithelial cells growing into connective tissue of the specimens. Regulation of MMP-13 expression was examined in cultured normal nonkeratinizing epithelial cells isolated from porcine periodontal ligament. In these cells, MMP-13 expression at the mRNA and protein level was potently enhanced (up to sixfold) by tumor necrosis factor-alpha, transforming growth factor-beta(1), and transforming growth factor-alpha and by keratinocyte growth factor in the presence of heparin. In addition, plating periodontal ligament epithelial cells on type I collagen stimulated MMP-13 expression (sevenfold) as compared with cells grown on tissue culture plastic. The results of this study show, that expression of MMP-13 is specifically induced in undifferentiated epithelial cells during chronic inflammation

  5. Electron microprobe analysis of frog skin epithelium: evidence for a syncytial sodium transport compartment.

    PubMed

    Rick, R; Dörge, A; von Arnim, E; Thurau, K

    1978-03-20

    For elucidation of the functional organization of frog skin epithelium with regard to transepithelial Na transport, electrolyte concentrations in individual epithelial cells were determined by electron microprobe analysis. The measurements were performed on 1-micron thick freeze-dried cryosections by an energy-dispersive X-ray detecting system. Quantification of the electrolyte concentrations was achieved by comparing the X-ray intensities obtained in the cells with those of an internal albumin standard. The granular, spiny, and germinal cells, which constitute the various layers of the epithelium, showed an identical behavior of their Na and K concentrations under all experimental conditions. In the control, both sides of the skin bathed in frog Ringer's solution, the mean cellular concentrations (in mmole/kg wet wt) were 9 for Na and 118 for K. Almost no change in the cellular Na occurred when the inside bathing solution was replaced by a Na-free isotonic Ringer's solution, whereas replacing the outside solution by distilled water resulted in a decrease of Na to almost zero in all layers. Inhibition of the transepithelial Na transport by ouabain (10(-4) M) produced in increase in Na to 109 and a decrease in K to 16. The effect of ouabain on the cellular Na and K concentrations was completely cancelled when the Na influx from the outside was prevented, either by removing Na or adding amiloride (10(-4) M). When, after the action of ouabain, Na was removed from the outside bathing solution, the Na and K concentration in all layers returned to control values. The latter effect could be abolished by amiloride. The other cell types of the epithelium showed under some experimental conditions a different behavior. In the cornified cells and the light cells, which occurred occasionally in the stratum granulosum, the electrolyte concentrations approximated those of the outer bathing medium under all experimental conditions. In the mitochondria-rich cells, the Na influx

  6. 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

  7. 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

  8. Epigenetic modifications and diabetic retinopathy.

    PubMed

    Kowluru, Renu A; Santos, Julia M; Mishra, Manish

    2013-01-01

    Diabetic retinopathy remains one of the most debilitating chronic complications, but despite extensive research in the field, the exact mechanism(s) responsible for how retina is damaged in diabetes remains ambiguous. Many metabolic pathways have been implicated in its development, and genes associated with these pathways are altered. Diabetic environment also facilitates epigenetics modifications, which can alter the gene expression without permanent changes in DNA sequence. The role of epigenetics in diabetic retinopathy is now an emerging area, and recent work has shown that genes encoding mitochondrial superoxide dismutase (Sod2) and matrix metalloproteinase-9 (MMP-9) are epigenetically modified, activates of epigenetic modification enzymes, histone lysine demethylase 1 (LSD1), and DNA methyltransferase are increased, and the micro RNAs responsible for regulating nuclear transcriptional factor and VEGF are upregulated. With the growing evidence of epigenetic modifications in diabetic retinopathy, better understanding of these modifications has potential to identify novel targets to inhibit this devastating disease. Fortunately, the inhibitors and mimics targeted towards histone modification, DNA methylation, and miRNAs are now being tried for cancer and other chronic diseases, and better understanding of the role of epigenetics in diabetic retinopathy will open the door for their possible use in combating this blinding disease. PMID:24286082

  9. [The plate in the zone of oocyte and germinal epithelium contact in scyphomedusa Aurelia aurita binds antibodies to ZP-domain-containing protein mesoglein].

    PubMed

    Adonin, L S; Podgornaia, O I; Matveev, I V; Shaposhnikova, T G

    2009-01-01

    Cnidaria are lower multicellular animals with the body consisting of two epithelial layers. An extracellular substance--mesoglea--is situated between epidermal and gastrodermal layers of these animals. Mesoglein is one of the major mesogleal proteins of adult medusa of Scyphozoan jellyfish Aurelia aurita. Search for the known domains in mesoglein amino acid sequence reveals prominent zona pellucida (ZP) domain (which was found at first in the mammal oocyte zona pellucida proteins), so the protein belongs to ZP family of extracellular matrix proteins and it is an early metazoan member of ZP-domain-containing protein family. However, nothing is known about oogenesis related ZP-domain proteins in the lower multicellular animals. Oogenesis in Scyphozoa is described poorly. In this work morphological features of the zone in contact area between the oocyte and the germinal epithelium were investigated in semi-fine sections: To make it more convenient we identified seven stages according to the oocyte size and the structure found in this area was named the plate. It was shown that the components of the plate bound specifically the antibodies against mesoglein. So it seems the plate material contains ZP-domain proteins. Electrophoresis and immunoblot results give evidence that the proteins immunologically related to mesoglein have a higher molecular mass. It might be due to either the posttranslational modifications of the precursors or that they represent other proteins of ZP-domain family in Cnidaria. PMID:19566035

  10. Salmonella gut invasion involves TTSS-2-dependent epithelial traversal, basolateral exit, and uptake by epithelium-sampling lamina propria phagocytes.

    PubMed

    Müller, Andreas J; Kaiser, Patrick; Dittmar, Kurt E J; Weber, Thomas C; Haueter, Sabine; Endt, Kathrin; Songhet, Pascal; Zellweger, Christa; Kremer, Marcus; Fehling, Hans-Jörg; Hardt, Wolf-Dietrich

    2012-01-19

    Salmonella Typhimurium causes diarrhea by infecting the epithelium and lamina propria of the intestinal mucosa and by secreting various effector proteins through type III secretion systems (TTSSs). However, the mechanisms by which Salmonella transverses the epithelium and is subsequently released into the lamina propria are poorly understood. Using a murine Salmonella-diarrhea model and in vivo microscopy, we show that epithelial traversal requires TTSS-1-mediated invasion and TTSS-2-dependent trafficking to the basolateral side. After being released into the lamina propria, the bacterium is transiently extracellular before being taken up by phagocytes, including CD11c(+)CX(3)CR1(high) monocytic phagocytes (MPs), which were found to constitutively sample cellular material shed from the basolateral side of the epithelium. Thus, Salmonella infects the cecal mucsa through a step-wise process wherein the bacterium transverses the epithelium through TTSS-2-dependent trafficking and then likely exploits lamina propria MPs, which are sampling the epithelium, to enter and replicate within the host. PMID:22264510

  11. 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

  12. 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

  13. 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

  14. 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.

  15. Lower intestinal modification of ureteral urine in hydrated house sparrows.

    PubMed

    Goldstein, D L; Braun, E J

    1986-01-01

    The ureters of birds empty into the posterior portion of the lower intestine, thereby providing the possibility for modification of ureteral urine by this latter organ. We have used in vivo perfusion to measure the transport of Na+, K+, and water across the lower intestine (colon and coprodaeum) of anesthetized house sparrows (Passer domesticus). Na+ was reabsorbed from (Vmax = approximately 22 mu eq . cm-2 . h-1, Km = approximately 69 meq/l) and K+ was secreted (at variable rates) into all saline perfusion fluids. The osmotic permeability of the intestinal epithelium was 0.39 microliter . cm-2 . h-1 . mosM-1 in the mucosal-to-serosal direction and 0.43 microliter . cm-2 . h-1 . mosM-1 in the serosal-to-mucosal direction. At isosmotic perfusion, Na+-linked water transport occurred at a rate of 1.7 microliter/mu eq Na+. In hydrated house sparrows the composition of ureteral urine (osmolarity = 351 mosM, Na+ = 86.5 meq/l, K+ = 60.5 meq/l) was significantly modified by transport in the lower intestine (voided fluid osmolarity = 344 mosM, Na+ = 60 meq/l, K+ = 90 meq/l). Interspecific comparisons of lower intestinal resorptive surface area and transport parameters at the level of the tissue, organ, and whole animal reveal no consistent pattern of adaptation related to habitat. PMID:3942257

  16. 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

  17. 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

  18. Physiologic and molecular changes in the tracheal epithelium of rats following burn injury

    PubMed Central

    Jacob, Sam; Zhu, Yong; Kraft, Robert; Cotto, Christopher; Carmical, Joseph R; Wood, Thomas G; Enkhbaatar, Perenlei; Herndon, David N; Hawkins, Hal K; Cox, Robert A

    2015-01-01

    Pneumonia is the leading complication in the critical care of burn victims. Airway epithelial dysfunction compromises host defense against pneumonia. The aim of this study is to test the hypothesis that burn injury alters the physiology of the airway epithelium. A rat model of 60% TBSA third degree scald burn was used. At 24 hours after injury, tracheal epithelial ultrastructure was studied using transmission electron microscopy (TEM) and proliferation was measured by Ki67 immunohistochemistry. Mucociliary clearance (MCC) was measured using fluorescent microspheres. The level of malondialdehyde (MDA), an indicator of lipid peroxidation, was also measured. Changes in epithelial mRNA expression were measured using microarray. Burn injury led to a ten-fold reduction in MCC that was statistically significant (p = 0.007) 24 hours after injury. No significant change was noted in the morphology of tracheal epithelial cells between groups, although a marginal increase in extracellular space was noted in injured animals. Ki67 nuclear expression was significantly reduced (25%, p = 0.008) in injured rats. There was a significant increase in MDA levels in the epithelial lysate of burned animals, p = 0.001. Microarray analysis identified 59 genes with significant differences between sham and injured animals. Burn injury altered multiple important functions in rat tracheal epithelium. The decrease in MCC and cell proliferation may be due to oxidative injury. Mechanistic studies to identify physiological processes associated with changes in airway function may help in designing therapeutic agents to reduce burn-induced airway pathogenesis. PMID:26064800

  19. 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

  20. Electrogenic transport and K+ ion channel expression by the human endolymphatic sac epithelium

    PubMed Central

    Kim, Sung Huhn; Kim, Bo Gyung; Kim, Jin Young; Roh, Kyung Jin; Suh, Michelle J.; Jung, JinSei; Moon, In Seok; Moon, Sung K.; Choi, Jae Young

    2015-01-01

    The endolymphatic sac (ES) is a cystic organ that is a part of the inner ear and is connected to the cochlea and vestibule. The ES is thought to be involved in inner ear ion homeostasis and fluid volume regulation for the maintenance of hearing and balance function. Many ion channels, transporters, and exchangers have been identified in the ES luminal epithelium, mainly in animal studies, but there has been no functional study investigating ion transport using human ES tissue. We designed the first functional experiments on electrogenic transport in human ES and investigated the contribution of K+ channels in the electrogenic transport, which has been rarely identified, even in animal studies, using electrophysiological/pharmacological and molecular biological methods. As a result, we identified functional and molecular evidence for the essential participation of K+ channels in the electrogenic transport of human ES epithelium. The identified K+ channels involved in the electrogenic transport were KCNN2, KCNJ14, KCNK2, and KCNK6, and the K+ transports via those channels are thought to play an important role in the maintenance of the unique ionic milieu of the inner ear fluid. PMID:26655723

  1. Enhancing effects of sericin on corneal wound healing in rat debrided corneal epithelium.

    PubMed

    Nagai, Noriaki; Murao, Takatoshi; Ito, Yoshimasa; Okamoto, Norio; Sasaki, Masahiro

    2009-05-01

    The protein sericin is the main constituent of silk. We demonstrate the effects of sericin on corneal wound healing in rat debrided corneal epithelium. We also determined the effects of sericin on cell adhesion and proliferation in a human cornea epithelial cell line (HCE-T). Epithelium was removed from the corneas of rats with a BD Micro-Sharp, and wounded corneas were dyed with a 1% fluorescein solution. The corneal wounds were monitored using a fundus camera TRC-50X equipped with a digital camera. The corneal wound of rats instilled with saline was approximately 10% healing at 12 h, and approximately 65% healing at 24 h after corneal epithelial abrasion. The corneal wounds of rats instilled with saline showed almost complete healing by 36 h after corneal epithelial abrasion. On the other hand, the corneal healing rate of rats instilled with sericin solution was higher than that of rats instilled with saline, and the corneal healing rate constant increased with increasing sericin concentration. In addition, the adhesion and proliferation of HCE-T cells treated with 0.01-0.5% sericin solutions were enhanced, reaching a maximum at treatments with 0.2 and 0.1% sericin solutions, respectively. The present study demonstrates that the instillation of sericin solution has a potent effect in promoting wound healing and wound-size reduction in rats, probably caused by increasing cell movement and proliferation. PMID:19420767

  2. Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium.

    PubMed

    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

  3. An Ultra-thin Amniotic Membrane as Carrier in Corneal Epithelium Tissue-Engineering

    PubMed Central

    Zhang, Liying; Zou, Dulei; Li, Sanming; Wang, Junqi; Qu, Yangluowa; Ou, Shangkun; Jia, Changkai; Li, Juan; He, Hui; Liu, Tingting; Yang, Jie; Chen, Yongxiong; Liu, Zuguo; Li, Wei

    2016-01-01

    Amniotic membranes (AMs) are widely used as a corneal epithelial tissue carrier in reconstruction surgery. However, the engineered tissue transparency is low due to the translucent thick underlying AM stroma. To overcome this drawback, we developed an ultra-thin AM (UAM) by using collagenase IV to strip away from the epithelial denuded AM (DAM) some of the stroma. By thinning the stroma to about 30 μm, its moist and dry forms were rendered acellular, optically clear and its collagen framework became compacted and inerratic. Engineered rabbit corneal epithelial cell (RCEC) sheets generated through expansion of limbal epithelial cells on UAM were more transparent and thicker than those expanded on DAM. Moreover, ΔNp63 and ABCG2 gene expression was greater in tissue engineered cell sheets expanded on UAM than on DAM. Furthermore, 2 weeks after surgery, the cornea grafted with UAM based cell sheets showed higher transparency and more stratified epithelium than the cornea grafted with DAM based cell sheets. Taken together, tissue engineered corneal epithelium generated on UAM has a preferable outcome because the transplanted tissue is more transparent and better resembles the phenotype of the native tissue than that obtained by using DAM for this procedure. UAM preserves compact layer of the amniotic membrane and maybe an ideal substrate for corneal epithelial tissue engineering. PMID:26876685

  4. A central role for vimentin in regulating repair function during healing of the lens epithelium

    PubMed Central

    Menko, A. S.; Bleaken, B. M.; Libowitz, A. A.; Zhang, L.; Stepp, M. A.; Walker, J. L.

    2014-01-01

    Mock cataract surgery provides a unique ex vivo model for studying wound repair in a clinically relevant setting. Here wound healing involves a classical collective migration of the lens epithelium, directed at the leading edge by an innate mesenchymal subpopulation of vimentin-rich repair cells. We report that vimentin is essential to the function of repair cells as the directors of the wound-healing process. Vimentin and not actin filaments are the predominant cytoskeletal elements in the lamellipodial extensions of the repair cells at the wound edge. These vimentin filaments link to paxillin-containing focal adhesions at the lamellipodial tips. Microtubules are involved in the extension of vimentin filaments in repair cells, the elaboration of vimentin-rich protrusions, and wound closure. The requirement for vimentin in repair cell function is revealed by both small interfering RNA vimentin knockdown and exposure to the vimentin-targeted drug withaferin A. Perturbation of vimentin impairs repair cell function and wound closure. Coimmunoprecipitation analysis reveals for the first time that myosin IIB is associated with vimentin, linking vimentin function in cell migration to myosin II motor proteins. These studies reveal a critical role for vimentin in repair cell function in regulating the collective movement of the epithelium in response to wounding. PMID:24478454

  5. 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

  6. Cell specialization in the epithelium of the small intestine of feeding Xenopus laevis tadpoles.

    PubMed Central

    Marshall, J A; Dixon, K E

    1978-01-01

    The intestinal epithelium of feeding Xenopus laevis tadpoles was studied using light microscope, electron microscope and autoradiographic techniques. The wall of the small intestine differs from that of most other vertebrates studied in that it lacks villous-like folds. A single prominent longitudinal fold, the typhlosole, forms about stage 49, and a series of shallow longitudinal epithelial pleats is also present in some animals. The morphology of the epithelial cells indicates that there are no differences between the cells in their degree of specialization. Three epithelial cell types were recognized: principal cells, gland cells and endocrine cells, making up about 65%, 15% and 1%, respectively, of all cells present, while approximately 20% of the cells in the epithelium are lymphocytes, 1% appear to be discharged gland cells, and 2% degenerating cells. No Paneth, caveolated or undifferentiated cells were identified. The findings are discussed in relation to other studies on cell proliferation and on nuclear transplantation. Images Figs. 3-4 Figs. 5-6 Figs. 7-8 Fig. 9 Fig. 10 Fig. 11 PMID:649494

  7. Constitutively active mutation of ACVR1 in oral epithelium causes submucous cleft palate in mice.

    PubMed

    Noda, Kazuo; Mishina, Yuji; Komatsu, Yoshihiro

    2016-07-15

    Cleft palate is among the most common human birth defects. Submucous cleft palate (SMCP) is a subgroup of cleft palate, which may be as common as overt cleft palate. Despite the high frequency of SMCP in humans, only recently have several animal models of SMCP begun to provide insight into the mechanisms by which SMCP develops. In this study, we show that enhanced BMP signaling through constitutively active ACVR1 in palatal epithelium causes submucous cleft palate in mice. In these mutant mice, the fusion of both palatal mesenchyme in hard palate, and muscles in soft palate were hampered by epithelial tissue. During palatal fusion, enhanced SMAD-dependent BMP signaling impaired cell death and altered cell proliferation rate in medial edge epithelium (MEE), and resulted in MEE persistence. At the molecular level, downregulation of ΔNp63, which is crucial for normal palatal fusion, in MEE cells was impaired, leading to a reduction in caspase-3 activation. Our study provides a new insight into the etiology of SMCP caused by augmented BMP signaling. PMID:26116174

  8. Sox2 Activates Cell Proliferation and Differentiation in the Respiratory Epithelium

    PubMed Central

    Tompkins, David H.; Besnard, Valérie; Lange, Alexander W.; Keiser, Angela R.; Wert, Susan E.; Bruno, Michael D.; Whitsett, Jeffrey A.

    2011-01-01

    Sox2, a transcription factor critical for the maintenance of embryonic stem cells and induction of pluripotent stem cells, is expressed exclusively in the conducting airway epithelium of the lung, where it is required for differentiation of nonciliated, goblet, and ciliated cells. To determine the role of Sox2 in respiratory epithelial cells, Sox2 was selectively and conditionally expressed in nonciliated airway epithelial cells and in alveolar type II cells in the adult mouse. Sox2 induced epithelial cell proliferation within 3 days of expression. Epithelial cell proliferation was associated with increased Ki-67 and cyclin D1 staining. Expression of cell cycle genes, including FoxM1, Ccna2 (Cyclin A2), Ccnb2 (Cyclin B2), and Ccnd1 (Cyclin D1), was increased. Consistent with a role in cell proliferation, Sox2 activated the transcription of FoxM1 in vitro. In alveoli, Sox2 caused hyperplasia and ectopic differentiation of epithelial cells to those with morphologic and molecular characteristics of conducting airway epithelium. Sox2 induced the expression of conducting airway epithelial specific genes, including Scgb1a1, Foxj1, Tubb3, and Cyp2f2. Although prolonged expression of Sox2 caused cell proliferation and epithelial hyperplasia, Sox2 did not induce pulmonary tumors. Sox2 induces proliferation of respiratory epithelial cells and, subsequently, partially reprograms alveolar epithelial cells into cells with characteristics of the conducting airways. PMID:20855650

  9. A Hormone-responsive 3D Culture Model of the Human Mammary Gland Epithelium.

    PubMed

    Speroni, Lucia; Sweeney, Michael F; Sonnenschein, Carlos; Soto, Ana M

    2016-01-01

    The process of mammary epithelial morphogenesis is influenced by hormones. The study of hormone action on the breast epithelium using 2D cultures is limited to cell proliferation and gene expression endpoints. However, in the organism, mammary morphogenesis occurs in a 3D environment. 3D culture systems help bridge the gap between monolayer cell culture (2D) and the complexity of the organism. Herein, we describe a 3D culture model of the human breast epithelium that is suitable to study hormone action. It uses the commercially available hormone-responsive human breast epithelial cell line, T47D, and rat tail collagen type 1 as a matrix. This 3D culture model responds to the main mammotropic hormones: estradiol, progestins and prolactin. The influence of these hormones on epithelial morphogenesis can be observed after 1- or 2-week treatment according to the endpoint. The 3D cultures can be harvested for analysis of epithelial morphogenesis, cell proliferation and gene expression. PMID:26891095

  10. A cost-effective system for differentiation of intestinal epithelium from human induced pluripotent stem cells.

    PubMed

    Ogaki, Soichiro; Morooka, Mayu; Otera, Kaito; Kume, Shoen

    2015-01-01

    The human intestinal epithelium is a useful model for pharmacological studies of absorption, metabolism, drug interactions, and toxicology, as well as for studies of developmental biology. We established a rapid and cost effective system for differentiation of human induced pluripotent stem (iPS) cells into definitive endoderm (DE) cells. In the presence of dimethyl sulfoxide (DMSO), a low concentration of Activin at 6.25 ng/ml is sufficient to give a similar differentiation efficiency with that using Activin at 100 ng/ml at the presence of Wnt activator. In the presence of DMSO, Activin at low concentration triggered hiPS cells to undergo differentiation through G1 arrest, reduce apoptosis, and potentiate activation of downstream targets, such as SMAD2 phosphorylation and SOX17 expression. This increased differentiation into CDX2 + SOX17 + DE cells. The present differentiation procedure therefore permits rapid and efficient derivation of DE cells, capable of differentiating into intestinal epithelium upon BIO and DAPT treatment and of giving rise to functional cells, such as enterocytes. PMID:26616277

  11. 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

  12. Identification of proteomic differences between squamous cell carcinoma of the lung and bronchial epithelium.

    PubMed

    Poschmann, Gereon; Sitek, Barbara; Sipos, Bence; Ulrich, Anna; Wiese, Sebastian; Stephan, Christian; Warscheid, Bettina; Klöppel, Günter; Vander Borght, Ann; Ramaekers, Frans C S; Meyer, Helmut E; Stühler, Kai

    2009-05-01

    Proteins that exhibit different expression levels in normal and malignant lung cells are good candidate biomarkers to improve early diagnosis and intervention. We used a quantitative approach and compared the proteome of microdissected cells from normal human bronchial epithelium and squamous cell carcinoma tumors of histopathological grades G2 and G3. DIGE analysis and subsequent MS-based protein identification revealed that 32 non-redundant proteins were differentially regulated between the respective tissue types. These proteins are mainly involved in energy pathways, cell growth or maintenance mechanisms, protein metabolism, and the regulation of DNA and RNA metabolism. The expression of some of these proteins was analyzed by immunohistochemistry using tissue microarrays containing tissue specimen of 55 patients, including normal bronchial epithelium, squamous cell carcinomas, adenocarcinomas, and large cell carcinomas. The results of the immunohistochemical studies correlated with the proteome study data and revealed that particularly HSP47 and a group of cytokeratins (i.e. cytokeratins 6a, 16, and 17) are significantly co-regulated in squamous cell carcinoma. Furthermore cytokeratin 17 showed significantly higher abundance in G2 grade compared with G3 grade squamous cell carcinomas in both the gel-based and the immunohistochemical analysis. Therefore this protein might be used as a marker for stratification between different tumor grades. PMID:19176476

  13. Matrilysin (Matrix Metalloproteinase-7) Mediates E-Cadherin Ectodomain Shedding in Injured Lung Epithelium

    PubMed Central

    McGuire, John K.; Li, Qinglang; Parks, William C.

    2003-01-01

    Matrilysin (matrix metalloproteinase-7) is highly expressed in lungs of patients with pulmonary fibrosis and other conditions associated with airway and alveolar injury. Although matrilysin is required for closure of epithelial wounds ex vivo, the mechanism of its action in repair is unknown. We demonstrate that matrilysin mediates shedding of E-cadherin ectodomain from injured lung epithelium both in vitro and in vivo. In alveolar-like epithelial cells, transfection of activated matrilysin resulted in shedding of E-cadherin and accelerated cell migration. In vivo, matrilysin co-localized with E-cadherin at the basolateral surfaces of migrating tracheal epithelium, and the reorganization of cell-cell junctions seen in wild-type injured tissue was absent in matrilysin-null samples. E-cadherin ectodomain was shed into the bronchoalveolar lavage fluid of bleomycin-injured wild-type mice, but was not shed in matrilysin-null mice. These findings identify E-cadherin as a novel substrate for matrilysin and indicate that shedding of E-cadherin ectodomain is required for epithelial repair. PMID:12759241

  14. 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.

  15. Thymic epithelium determines a spontaneous chronic neuritis in Icam1(tm1Jcgr)NOD mice.

    PubMed

    Meyer zu Horste, Gerd; Mausberg, Anne K; Cordes, Steffen; El-Haddad, Houda; Partke, Hans-Joachim; Leussink, Verena I; Roden, Michael; Martin, Stephan; Steinman, Lawrence; Hartung, Hans-Peter; Kieseier, Bernd C

    2014-09-15

    The NOD mouse strain spontaneously develops autoimmune diabetes. A deficiency in costimulatory molecules, such as B7-2, on the NOD genetic background prevents diabetes but instead triggers an inflammatory peripheral neuropathy. This constitutes a shift in the target of autoimmunity, but the underlying mechanism remains unknown. In this study, we demonstrate that NOD mice deficient for isoforms of ICAM-1, which comediate costimulatory functions, spontaneously develop a chronic autoimmune peripheral neuritis instead of diabetes. The disease is transferred by CD4(+) T cells, which infiltrate peripheral nerves together with macrophages and B cells and are autoreactive against peripheral myelin protein zero. These Icam1(tm1Jcgr)NOD mice exhibit unaltered numbers of regulatory T cells, but increased IL-17-producing T cells, which determine the severity, but not the target specificity, of autoimmunity. Ab-mediated ICAM-1 blockade triggers neuritis only in young NOD mice. Thymic epithelium from Icam1(tm1Jcgr)NOD mice features an altered expression of costimulatory molecules and induces neuritis and myelin autoreactivity after transplantation into nude mice in vivo. Icam1(tm1Jcgr)NOD mice exhibit a specifically altered TCR repertoire. Our findings introduce a novel animal model of chronic inflammatory neuropathies and indicate that altered expression of ICAM-1 on thymic epithelium shifts autoimmunity specifically toward peripheral nerves. This improves our understanding of autoimmunity in the peripheral nervous system with potential relevance for human diseases. PMID:25108020

  16. Excessive Myosin Activity in Mbs Mutants Causes Photoreceptor Movement Out of the Drosophila Eye Disc Epithelium

    PubMed Central

    Lee, Arnold; Treisman, Jessica E.

    2004-01-01

    Neuronal cells must extend a motile growth cone while maintaining the cell body in its original position. In migrating cells, myosin contraction provides the driving force that pulls the rear of the cell toward the leading edge. We have characterized the function of myosin light chain phosphatase, which down-regulates myosin activity, in Drosophila photoreceptor neurons. Mutations in the gene encoding the myosin binding subunit of this enzyme cause photoreceptors to drop out of the eye disc epithelium and move toward and through the optic stalk. We show that this phenotype is due to excessive phosphorylation of the myosin regulatory light chain Spaghetti squash rather than another potential substrate, Moesin, and that it requires the nonmuscle myosin II heavy chain Zipper. Myosin binding subunit mutant cells continue to express apical epithelial markers and do not undergo ectopic apical constriction. In addition, mutant cells in the wing disc remain within the epithelium and differentiate abnormal wing hairs. We suggest that excessive myosin activity in photoreceptor neurons may pull the cell bodies toward the growth cones in a process resembling normal cell migration. PMID:15075368

  17. Familial bilateral combined hamartoma of retina and retinal pigment epithelium associated with neurofibromatosis 1.

    PubMed

    Yassin, Sanaa A; Al-Tamimi, Elham R

    2012-04-01

    We report a family of three siblings followed between 2005 and 2011 with bilateral combined hamartoma of the retina and retinal pigment epithelium, with the age of diagnosis ranging from 7 to 13 years. The main reason for consultation was reduction of vision and squint. The diagnosis was determined based on the clinical findings on fundus examination: increased pigmentation at the macula with slightly elevated, gray-white macular lesion, tortuosity of perimacular blood vessels and glial epiretinal membrane. The elder brother was found to have left posterior subcapsular cataract. He was also confirmed to have neurofibromatosis type 1, the youngest sister fit in the diagnostic criteria for neurofibromatosis type 1, while the middle sister was presumed to have neurofibromatosis type 1. Follow-up showed stability of the retinal lesion in the three cases, with the progression to develop right posterior subcapsular cataract in the elder sister. This report is aimed to demonstrate that the occurrence of bilateral combined hamartoma of the retina and retinal pigment epithelium could raise the possibility of associated neurofibromatosis. PMID:23960997

  18. Alterations of retinal pigment epithelium cause AMD-like retinopathy in senescence-accelerated OXYS rats

    PubMed Central

    Markovets, Anton M.; Saprunova, Valeriya B.; Zhdankina, Anna A.; Fursova, Anzhella Zh.; Bakeeva, Lora E.; Kolosova, Natalia G.

    2011-01-01

    Pathogenesis of age-related macular degeneration (AMD), the leading cause of blindness in the world, remains poorly understood. This makes it necessary to create animal models for studying AMD pathogenesis and to design new therapeutic approaches. Here we showed that retinopathy in OXYS rats is similar to human AMD according to clinical signs, morphology, and vascular endothelium growth factor (VEGF) and pigment epithelium-derived factor (PEDF) genes expression. Clinical signs of retinopathy OXYS rats manifest by the age 3 months against the background of significantly reduced expression level of VEGF and PEDF genes due to the decline of the amount of retinal pigment epithelium (RPE) cells and alteration of choroidal microcirculation. The disruption in OXYS rats' retina starts at the age of 20 days and appears as reduce the area of RPE cells but does not affect their ultrastructure. Ultrastructural pathological alterations of RPE as well as develop forms of retinopathy are observed in OXYS rats from age 12 months and manifested as excessive accumulation of lipofuscin in RPE regions adjacent to the rod cells, whirling extentions of the basement membrane into the cytoplasm. These data suggest that primary cellular degenerative alterations in the RPE cells secondarily lead to choriocapillaris atrophy and results in complete loss of photoreceptor cells in the OXYS rats' retina by the age of 24 months. PMID:21191149

  19. Tight junction proteins in gallbladder epithelium: different expression in acute acalculous and calculous cholecystitis.

    PubMed

    Laurila, Jouko J; Karttunen, Tuomo; Koivukangas, Vesa; Laurila, Päivi A; Syrjälä, Hannu; Saarnio, Juha; Soini, Ylermi; Ala-Kokko, Tero I

    2007-06-01

    There is a paucity of information of tight junction (TJ) proteins in gallbladder epithelium, and disturbances in the structure of these proteins may play a role in the pathogenesis of acute acalculous cholecystitis (AAC) and acute calculous cholecystitis (ACC). Using immunohistochemistry, we investigated the expression of TJ proteins claudin-1, -2, -3, and -4, occludin, zonula occludens (ZO-1), and E-cadherin in 9 normal gallbladders, 30 gallbladders with AAC, and 21 gallbladders with ACC. The number of positive epithelial and endothelial cells and the intensity of the immunoreaction were determined. Membrane-bound and cytoplasmic immunoreactivities were separately assessed. We found that TJ proteins were uniformly expressed in normal gallbladder epithelium, with the exception of claudin-2, which was present in less than half of the cells. In AAC, expression of cytoplasmic occludin and claudin-1 were decreased, as compared with normal gallbladder. In ACC, expression of claudin-2 was increased, and expression of claudin-1, -3, and -4, occludin, and ZO-1 were decreased, as compared with normal gallbladder or AAC. We conclude that there are significant differences in expression of TJ proteins in AAC and ACC, supporting the idea that AAC represents a manifestation of systemic inflammatory disease, whereas ACC is a local inflammatory and often infectious disease. PMID:17283368

  20. The Impact of Type 1 Diabetes Mellitus on Corneal Epithelial Nerve Morphology and the Corneal Epithelium

    PubMed Central

    Cai, Daniel; Zhu, Meifang; Petroll, W. Matthew; Koppaka, Vindhya; Robertson, Danielle M.

    2015-01-01

    Diabetic corneal neuropathy can result in chronic, sight-threatening corneal pathology. Although the exact etiology is unknown, it is believed that a reduction in corneal sensitivity and loss of neurotrophic support contributes to corneal disease. Information regarding the relationship between nerve loss and effects on the corneal epithelium is limited. We investigated changes in the corneal epithelium and nerve morphology using three-dimensional imaging in vivo and in situ in a streptozotocin-induced diabetic mouse model. Streptozotocin-treated mice showed increased levels of serum glucose and growth retardation consistent with a severe diabetic state. A reduction in the length of the subbasal nerve plexus was evident after 6 weeks of disease. Loss of the subbasal nerve plexus was associated with corneal epithelial thinning and a reduction in basal epithelial cell density. In contrast, loss of the terminal epithelial nerves was associated with animal age. Importantly, this is the first rodent model of type 1 diabetes that shows characteristics of corneal epithelial thinning and a reduction in basal epithelial cell density, both previously have been documented in humans with diabetic corneal neuropathy. These findings indicate that in type 1 diabetes, nerve fiber damage is evident in the subbasal nerve plexus before terminal epithelial nerve loss and that neurotrophic support from both the subbasal nerve plexus and terminal epithelial nerves is essential for the maintenance of corneal epithelial homeostasis. PMID:25102563

  1. 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

  2. A microfluidic device to apply shear stresses to polarizing ciliated airway epithelium using air flow

    PubMed Central

    Trieu, Dennis; Waddell, Thomas K.; McGuigan, Alison P.

    2014-01-01

    Organization of airway epithelium determines ciliary beat direction and coordination for proper mucociliary clearance. Fluidic shear stresses have the potential to influence ciliary organization. Here, an in vitro fluidic flow system was developed for inducing long-term airflow shear stresses on airway epithelium with a view to influencing epithelial organization. Our system consists of a fluidic device for cell culture, integrated into a humidified airflow circuit. The fluidic device has a modular design and is made from a combination of polystyrene and adhesive components incorporated into a 6-well filter membrane insert. We demonstrate the system operates within physiologically relevant shear and pressure ranges and estimate the shear stress exerted on the epithelial cell layer as a result of air flow using a computational model. For both the bronchial epithelial cell line BEAS2B and primary human tracheal airway epithelial cells, we demonstrate that cells remain viable within the device when exposed to airflow for 24 h and that normal differentiation and cilia formation occurs. Furthermore, we demonstrate the utility of our device for exploring the impact of exposing cells to airflow: our tool enables quantification of cytoskeletal organization, and is compatible with in situ bead assays to assess the orientation of cilia beating. PMID:25553181

  3. Type I Interferons Control Proliferation and Function of the Intestinal Epithelium.

    PubMed

    Katlinskaya, Yuliya V; Katlinski, Kanstantsin V; Lasri, Audrey; Li, Ning; Beiting, Daniel P; Durham, Amy C; Yang, Ting; Pikarsky, Eli; Lengner, Christopher J; Johnson, F Brad; Ben-Neriah, Yinon; Fuchs, Serge Y

    2016-01-01

    Wnt pathway-driven proliferation and renewal of the intestinal epithelium must be tightly controlled to prevent development of cancer and barrier dysfunction. Although type I interferons (IFN) produced in the gut under the influence of microbiota are known for their antiproliferative effects, the role of these cytokines in regulating intestinal epithelial cell renewal is largely unknown. Here we report a novel role for IFN in the context of intestinal knockout of casein kinase 1α (CK1α), which controls the ubiquitination and degradation of both β-catenin and the IFNAR1 chain of the IFN receptor. Ablation of CK1α leads to the activation of both β-catenin and IFN pathways and prevents the unlimited proliferation of intestinal epithelial cells despite constitutive β-catenin activity. IFN signaling contributes to the activation of the p53 pathway and the appearance of apoptotic and senescence markers in the CK1α-deficient gut. Concurrent genetic ablation of CK1α and IFNAR1 leads to intestinal hyperplasia, robust attenuation of apoptosis, and rapid and lethal loss of barrier function. These data indicate that IFN play an important role in controlling the proliferation and function of the intestinal epithelium in the context of β-catenin activation. PMID:26811327

  4. A cost-effective system for differentiation of intestinal epithelium from human induced pluripotent stem cells

    PubMed Central

    Ogaki, Soichiro; Morooka, Mayu; Otera, Kaito; Kume, Shoen

    2015-01-01

    The human intestinal epithelium is a useful model for pharmacological studies of absorption, metabolism, drug interactions, and toxicology, as well as for studies of developmental biology. We established a rapid and cost effective system for differentiation of human induced pluripotent stem (iPS) cells into definitive endoderm (DE) cells. In the presence of dimethyl sulfoxide (DMSO), a low concentration of Activin at 6.25 ng/ml is sufficient to give a similar differentiation efficiency with that using Activin at 100 ng/ml at the presence of Wnt activator. In the presence of DMSO, Activin at low concentration triggered hiPS cells to undergo differentiation through G1 arrest, reduce apoptosis, and potentiate activation of downstream targets, such as SMAD2 phosphorylation and SOX17 expression. This increased differentiation into CDX2 + SOX17 + DE cells. The present differentiation procedure therefore permits rapid and efficient derivation of DE cells, capable of differentiating into intestinal epithelium upon BIO and DAPT treatment and of giving rise to functional cells, such as enterocytes. PMID:26616277

  5. The osmotic behaviour of toad skin epithelium (Bufo viridis). an electron microprobe analysis.

    PubMed

    Rick, R; Dörge, A; Katz, U; Bauer, R; Thurau, K

    1980-05-01

    The effect of saline adaptation on the intracellular Na, K, Cl, P concentrations and dry weight content of the toad skin epithelium (Bufo viridis) was studied using the technique of electron microprobe analysis. The measurements were performed on isolated abdominal skins either directly after dissection or after additional incubation in Ussing-type chambers. Adaptations of the toads to increasing NaCl concentrations for 7 days resulted in increased blood plasma osmolarity and a parallel increase in the cellular electrolyte, P and dry weight concentrations of the epithelium, the K increase representing the most significant fraction of the intracellular osmolarity increase. No evidence was obtained to show that the nucleus and cytoplasm reacted differently from each other and all living epithelial cell types basically showed the same response. Incubation of the isolated skins under control conditions showed a drastic inhibition of the transepithelial Na transport after adaptation to high salinities. In spite of the large variations in the transport rate almost identical intracellular electrolyte concentrations were observed. In tap water adapted toads the average cellular concentrations were 8.8 mmole/kg wet weight for Na, 109.6 for K, 41.5 for Cl, and 135.3 for P, respectively. Incubation of the skin with Ringer's solution of different osmolarities demonstrated that the epithelial cells are in osmotic equilibrium with the inner bathing solution. The results are consistent with the view that the osmotic adaptation is mainly accomplished by the movement of water. PMID:7191092

  6. 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. PMID:26061394

  7. The Effects of Silicone Hydrogel Lens Wear on the Corneal Epithelium and Risk for Microbial Keratitis

    PubMed Central

    Robertson, Danielle M.

    2012-01-01

    Previous studies using animal models and human clinical trials have demonstrated that the use of low oxygen transmissible contact lens materials produce corneal epithelial surface damage resulting in increased Pseudomonas aeruginosa (PA) adhesion and raft-mediated internalization into surface corneal epithelial cells. These findings led to the testable clinical predictions that: (1) microbial keratitis (MK) risk is expected to be greatest during the first 6 months of wear; (2) there is no difference between 6 and 30 night extended wear; and (3) that wear of hyper-oxygen transmissible lenses would reduce the reported incidence of infection. Subsequent epidemiological studies have confirmed the first two predictions; however, increased oxygen transmissibility with silicone hydrogel (SiHy) lens wear has not altered the overall incidence of MK. In this review, more recent clinical and basic studies that investigate epithelial alterations and bacterial adhesion to corneal epithelial cells following wear of SiHy lenses with and without concomitant exposure to chemically preserved multipurpose solutions (MPS) will be examined. The collective results of these studies demonstrate that even in the absence of lens-related hypoxia, MPS induce ocular surface changes during SiHy lens wear which are associated with a pathophysiological increase in PA adherence and internalization in the corneal epithelium, and therefore, predict an increased risk for PA-MK. In addition, new data supporting an interactive role for inflammation in facilitating PA adherence and internalization in the corneal epithelium will also be discussed. PMID:23266590

  8. 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

  9. Peptidoglycan recognition protein expression in mouse Peyer's Patch follicle associated epithelium suggests functional specialization.

    PubMed

    Lo, David; Tynan, Wendy; Dickerson, Janet; Mendy, Jason; Chang, Hwai-Wen; Scharf, Melinda; Byrne, Daragh; Brayden, David; Higgins, Lisa; Evans, Claire; O'Mahony, Daniel J

    2003-07-01

    Mammalian Peyer's Patches possess specialized epithelium, the follicle associated epithelium (FAE), and specialized cells called M cells which mediate transcytosis of antigens to underlying lymphoid tissue. To identify FAE specific genes, we used TOGA gene expression profiling of microdissected mouse Peyer's Patch tissue. We found expression of laminin beta3 across the FAE, and scattered expression of peptidoglycan recognition protein (PGRP)-S. Using the M cell specific lectin Ulex europaeus agglutinin 1 (UEA-1), PGRP-S expression was nearly exclusively co-localized with UEA-1+ M cells. By contrast, the related gene PGRP-L was expressed among a subset of UEA-1 negative FAE cells. Expression of these proteins in transfected cells demonstrated distinct subcellular localization. PGRP-S showed a vesicular pattern and extracellular secretion, while PGRP-L showed localization to both the cytoplasm and the cell surface. The potential function of these PGRP proteins as pattern recognition receptors and their distinctive cellular distribution suggests a complex coordination among specialized cells of the FAE in triggering mucosal immunity and innate immune responses. PMID:14572796

  10. Magnetic Nanoparticles as Intraocular Drug Delivery System to Target Retinal Pigmented Epithelium (RPE)

    PubMed Central

    Giannaccini, Martina; Giannini, Marianna; Calatayud, M. Pilar; Goya, Gerardo F.; Cuschieri, Alfred; Dente, Luciana; Raffa, Vittoria

    2014-01-01

    One of the most challenging efforts in drug delivery is the targeting of the eye. The eye structure and barriers render this organ poorly permeable to drugs. Quite recently the entrance of nanoscience in ocular drug delivery has improved the penetration and half-life of drugs, especially in the anterior eye chamber, while targeting the posterior chamber is still an open issue. The retina and the retinal pigment epithelium/choroid tissues, located in the posterior eye chamber, are responsible for the majority of blindness both in childhood and adulthood. In the present study, we used magnetic nanoparticles (MNPs) as a nanotool for ocular drug delivery that is capable of specific localization in the retinal pigmented epithelium (RPE) layer. We demonstrate that, following intraocular injection in Xenopus embryos, MNPs localize specifically in RPE where they are retained for several days. The specificity of the localization did not depend on particle size and surface properties of the MNPs used in this work. Moreover, through similar experiments in zebrafish, we demonstrated that the targeting of RPE by the nanoparticles is not specific for the Xenopus species. PMID:24451140

  11. The GTPase ARFRP1 controls the lipidation of chylomicrons in the Golgi of the intestinal epithelium.

    PubMed

    Jaschke, Alexander; Chung, Bomee; Hesse, Deike; Kluge, Reinhart; Zahn, Claudia; Moser, Markus; Petzke, Klaus-Jürgen; Brigelius-Flohé, Regina; Puchkov, Dmytro; Koepsell, Hermann; Heeren, Joerg; Joost, Hans-Georg; Schürmann, Annette

    2012-07-15

    The uptake and processing of dietary lipids by the small intestine is a multistep process that involves several steps including vesicular and protein transport. The GTPase ADP-ribosylation factor-related protein 1 (ARFRP1) controls the ARF-like 1 (ARL1)-mediated Golgi recruitment of GRIP domain proteins which in turn bind several Rab-GTPases. Here, we describe the essential role of ARFRP1 and its interaction with Rab2 in the assembly and lipidation of chylomicrons in the intestinal epithelium. Mice lacking Arfrp1 specifically in the intestine (Arfrp1(vil-/-)) exhibit an early post-natal growth retardation with reduced plasma triacylglycerol and free fatty acid concentrations. Arfrp1(vil-/-) enterocytes as well as Arfrp1 mRNA depleted Caco-2 cells absorbed fatty acids normally but secreted chylomicrons with a markedly reduced triacylglycerol content. In addition, the release of apolipoprotein A-I (ApoA-I) was dramatically decreased, and ApoA-I accumulated in the Arfrp1(vil-/-) epithelium, where it predominantly co-localized with Rab2. The release of chylomicrons from Caco-2 was markedly reduced after the suppression of Rab2, ARL1 and Golgin-245. Thus, the GTPase ARFRP1 and its downstream proteins are required for the lipidation of chylo-microns and the assembly of ApoA-I to these particles in the Golgi of intestinal epithelial cells. PMID:22505585

  12. 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

  13. 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

  14. Fly ash-induced changes in hamster tracheal epithelium in vivo and in vitro

    SciTech Connect

    Schiff, L.J.; Byrne, M.M.; Graham, J.A.

    1981-09-01

    The effects of fly ash from a coal-fired power plant on tracheal epithelium of CrRGH (SYR) Syrian golden hamsters were studied in organ cultures and after in vivo exposures. The tracheal epithelium of animals receiving 5-9 daily (5 d/wk) 3-h exposures to 2 mg fly ash per cubic meter showed large areas of basal cell hyperplasia and stratification. Surface alterations characteristic of stratified metaplasia were observed. Exposure to 1 mg/m/sup 3/ produced diffuse basal cell hyperplasia. Hamster tracheal ring cultures exposed in vitro to 50 ..mu..g/ml fly ash for 1 h/d or to 10 ..mu..g/ml for 3 h/d showed epithelial changes similar to those observed in vivo. Whole suckling hamster tracheas in organ culture exposed to fly ash at concentrations of 10 and 50 ..mu..g/ml for 1 or 3 h/d exhibited cornifying epidermoid metaplasia after 7 exposures. The most characteristic findings in surface cells were broad metaplastic areas with keratin formation.

  15. Ultrastructural characteristics of carcinogen-induced nondysplastic changes in tracheal epithelium

    SciTech Connect

    Klein-Szanto, A.J.P.; Topping, D.C.; Heckman, C.A.; Nettesheim, P.

    1980-01-01

    Nondysplastic hypotrophic and metaplastic epithelial alterations induced by dimethylbenz(a)anthracene in isogenic tracheal transplants were studied by light and electron microscopy 3 to 24 months after cessation of a 4-week carcinogen exposure. Hypotrophic epithelium observed at all time points was characterized by the presence of nonciliated cells that adopted either cuboidal or squamous shapes, forming simple or bistratified epithelia. Most of these cells, as well as some metaplastic cells, exhibited features of mucin-secreting cells. The metaplastic epithelia showed nonkeratinizing squamous metaplasia, closely related to transitional metaplasia, and keratinizing squamous metaplasia, which presented either an atrophic or an acanthotic epithelium. Although many of these epithelia showed morphologic features of normal stratified epithelia, several nonkeratinizing squamous metaplasias and acanthotic keratinizing squamous metaplasias exhibited some irregularities, probably representing very early atypical ultrastructural features (i.e., perinuclear concentration of tonofilament bundles, the presence of dark and clear basal epithelial cells, interruptions and alterations of the basal lamina). These features were not observed in a group of early squamous metaplasias studied for comparative purposes 2 weeks after cessation of dimethylbenz(a)anthracene exposure, which were characterized by a combination of degenerative phenomena and increased cell proliferation.

  16. 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.

  17. Ror2 regulates branching, differentiation, and actin-cytoskeletal dynamics within the mammary epithelium

    PubMed Central

    Roarty, Kevin; Shore, Amy N.; Creighton, Chad J.

    2015-01-01

    Wnt signaling encompasses β-catenin–dependent and –independent networks. How receptor context provides Wnt specificity in vivo to assimilate multiple concurrent Wnt inputs throughout development remains unclear. Here, we identified a refined expression pattern of Wnt/receptor combinations associated with the Wnt/β-catenin–independent pathway in mammary epithelial subpopulations. Moreover, we elucidated the function of the alternative Wnt receptor Ror2 in mammary development and provided evidence for coordination of this pathway with Wnt/β-catenin–dependent signaling in the mammary epithelium. Lentiviral short hairpin RNA (shRNA)-mediated depletion of Ror2 in vivo increased branching and altered the differentiation of the mammary epithelium. Microarray analyses identified distinct gene level alterations within the epithelial compartments in the absence of Ror2, with marked changes observed in genes associated with the actin cytoskeleton. Modeling of branching morphogenesis in vitro defined specific defects in cytoskeletal dynamics accompanied by Rho pathway alterations downstream of Ror2 loss. The current study presents a model of Wnt signaling coordination in vivo and assigns an important role for Ror2 in mammary development. PMID:25624393

  18. The impact of type 1 diabetes mellitus on corneal epithelial nerve morphology and the corneal epithelium.

    PubMed

    Cai, Daniel; Zhu, Meifang; Petroll, W Matthew; Koppaka, Vindhya; Robertson, Danielle M

    2014-10-01

    Diabetic corneal neuropathy can result in chronic, sight-threatening corneal pathology. Although the exact etiology is unknown, it is believed that a reduction in corneal sensitivity and loss of neurotrophic support contributes to corneal disease. Information regarding the relationship between nerve loss and effects on the corneal epithelium is limited. We investigated changes in the corneal epithelium and nerve morphology using three-dimensional imaging in vivo and in situ in a streptozotocin-induced diabetic mouse model. Streptozotocin-treated mice showed increased levels of serum glucose and growth retardation consistent with a severe diabetic state. A reduction in the length of the subbasal nerve plexus was evident after 6 weeks of disease. Loss of the subbasal nerve plexus was associated with corneal epithelial thinning and a reduction in basal epithelial cell density. In contrast, loss of the terminal epithelial nerves was associated with animal age. Importantly, this is the first rodent model of type 1 diabetes that shows characteristics of corneal epithelial thinning and a reduction in basal epithelial cell density, both previously have been documented in humans with diabetic corneal neuropathy. These findings indicate that in type 1 diabetes, nerve fiber damage is evident in the subbasal nerve plexus before terminal epithelial nerve loss and that neurotrophic support from both the subbasal nerve plexus and terminal epithelial nerves is essential for the maintenance of corneal epithelial homeostasis. PMID:25102563

  19. [The reaction of acclimated isolated gill epithelium of mollusc to a short-term superoptimal heating].

    PubMed

    Mironova, A P

    2002-01-01

    Thermoresistance (TR) of isolated gill epithelium of molluscs Anodonta anatina L. (n = 20) acclimated for 72 h at 24 degrees C was studied. In 1, 2, 12, 24, 36, 48, 60, and 72 h, the gills were submitted to a provoking action: a 10-minutes heating at 36 degrees C. As a criterion of the tissue TR level served a logarithmic index of the time of survival at 40 degrees C. During 24 h, negative correlation (about 0.50) was revealed between the acclimated epithelium TR level and the value and direction (sign) of its change under the provoking action. In 36 h, this coefficient fell to 0.13. As a result, the range of interorganism variability of the tissue TR level enlarged. Meanwhile, a decrease in the acclimated tissue mean TR level occurred as late as in 60 h of the experiment, being equal to 21%. In 72 h, it reached 30%, which traditionally indicates a deterioration of the functional state of tissue cells and a subsequent death. However, we believe that the deterioration of this state actually had happened earlier, in 36 h, when the range of the interorganism variability of the tissue TR level became enlarged. It was at this moment that the acclimated tissue lost its ability to regulate the shift in stability with the TR level at this period of acclimation. PMID:11868464

  20. 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

  1. Quantitative Assessment of Human Neutrophil Migration Across a Cultured Bladder Epithelium

    PubMed Central

    Lau, Megan E.; Hunstad, David A.

    2013-01-01

    The recruitment of immune cells from the periphery to the site of inflammation is an essential step in the innate immune response at any mucosal surface. During infection of the urinary bladder, polymorphonuclear leukocytes (PMN; neutrophils) migrate from the bloodstream and traverse the bladder epithelium. Failure to resolve infection in the absence of a neutrophilic response demonstrates the importance of PMN in bladder defense. To facilitate colonization of the bladder epithelium, uropathogenic Escherichia coli (UPEC), the causative agent of the majority of urinary tract infections (UTIs), dampen the acute inflammatory response using a variety of partially defined mechanisms. To further investigate the interplay between host and bacterial pathogen, we developed an in vitro model of this aspect of the innate immune response to UPEC. In the transuroepithelial neutrophil migration assay, a variation on the Boyden chamber, cultured bladder epithelial cells are grown to confluence on the underside of a permeable support. PMN are isolated from human venous blood and are applied to the basolateral side of the bladder epithelial cell layers. PMN migration representing the physiologically relevant basolateral-to-apical direction in response to bacterial infection or chemoattractant molecules is enumerated using a hemocytometer. This model can be used to investigate interactions between UPEC and eukaryotic cells as well as to interrogate the molecular requirements for the traversal of bladder epithelia by PMN. The transuroepithelial neutrophil migration model will further our understanding of the initial inflammatory response to UPEC in the bladder. PMID:24300797

  2. Retinal pigment epithelium, age-related macular degeneration and neurotrophic keratouveitis.

    PubMed

    Bianchi, Enrica; Scarinci, Fabio; Ripandelli, Guido; Feher, Janos; Pacella, Elena; Magliulo, Giuseppe; Gabrieli, Corrado Balacco; Plateroti, Rocco; Plateroti, Pasquale; Mignini, Fiorenzo; Artico, Marco

    2013-01-01

    Age-related macular degeneration (AMD) is the leading cause of impaired vision and blindness in the aging population. The aims of our studies were to identify qualitative and quantitative alterations in mitochondria in human retinal pigment epithelium (RPE) from AMD patients and controls and to test the protective effects of pigment epithelium-derived factor (PEDF), a known neurotrophic and antiangiogenic substance, against neurotrophic keratouveitis. Histopathological alterations were studied by means of morphometry, light and electron microscopy. Unexpectedly, morphometric data showed that the RPE alterations noted in AMD may also develop in normal aging, 10-15 years later than appearing in AMD patients. Reduced tear secretion, corneal ulceration and leukocytic infiltration were found in capsaicin (CAP)-treated rats, but this effect was significantly attenuated by PEDF. These findings suggest that PEDF accelerated the recovery of tear secretion and also prevented neurotrophic keratouveitis and vitreoretinal inflammation. PEDF may have a clinical application in inflammatory and neovascular diseases of the eye. PMID:23128960

  3. Transplantation of cultured rabbit retinal epithelium to rabbit retina using a closed-eye method.

    PubMed

    Lopez, R; Gouras, P; Brittis, M; Kjeldbye, H

    1987-07-01

    We have developed a closed-eye technique for transplanting cultured rabbit retinal epithelial cells to Bruch's membrane of the rabbit. A glass micropipette containing a suspension of 3H-thymidine-labeled, cultured retinal pigment epithelial (RPE) cells is inserted through a pars plana incision and positioned adjacent to the neural retina. A jet stream from the pipette is used to make a small retinal hole and bleb detachment. Patches of host retinal epithelium lift off with the neural retina, creating areas of bare Bruch's membrane. The cell suspension is injected into the subretinal space, and labeled cells can be seen attached to Bruch's membrane as early as 1 hr later. The neural retina spontaneously reattaches within 24 to 48 hr, bringing photoreceptor outer segments in direct contact with the transplanted cells. Phagocytosis of outer segment material by transplanted cells can be seen as early as 24 hr after surgery. This closed-eye technique offers an advantage over the open-sky method used previously in that it allows for reattachment of the neural retina and at least a partial return of function in the transplanted retinal epithelium. PMID:3596991

  4. 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

  5. The endogenous chromophore of retinal G protein-coupled receptor opsin from the pigment epithelium.

    PubMed

    Hao, W; Fong, H K

    1999-03-01

    The recent identification of nonvisual opsins has revealed an expanding family of vertebrate opsin genes. The retinal pigment epithelium (RPE) and Müller cells contain a blue and UV light-absorbing opsin, the RPE retinal G protein-coupled receptor (RGR, or RGR opsin). The spectral properties of RGR purified from bovine RPE suggest that RGR is conjugated in vivo to a retinal chromophore through a covalent Schiff base bond. In this study, the isomeric structure of the endogenous chromophore of RGR was identified by the hydroxylamine derivatization method. The retinaloximes derived from RGR in the dark consisted predominantly of the all-trans isomer. Irradiation of RGR with 470-nm monochromatic or near-UV light resulted in stereospecific isomerization of the bound all-trans-retinal to an 11-cis configuration. The stereospecificity of photoisomerization of the all-trans-retinal chromophore of RGR was lost by denaturation of the protein in SDS. Under the in vitro conditions, the photosensitivity of RGR is at least 34% that of bovine rhodopsin. These results provide evidence that RGR is bound in vivo primarily to all-trans-retinal and is capable of operating as a stereospecific photoisomerase that generates 11-cis-retinal in the pigment epithelium. PMID:10037690

  6. 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.

  7. Mapping chromatin modifications in nanochannels

    NASA Astrophysics Data System (ADS)

    Lim, Shuang Fang; Karpusenko, Alena; Riehn, Robert

    2013-03-01

    DNA and chromatin are elongated to a fixed fraction of their contour length when introduced into quasi-1d nanochannels. Because single molecules are analyzed, their hold great potential for the analysis for the genetic analysis of material from single cells. In this study, we have reconstituted chromatin with histones from a variety of sources, and mapped the modification profile of the chromatin. We monitored methylation and acetylation patterns of the histone tail protein residues using fluorescently labelled antibodies. Using those, we distinguished chromatin reconstituted from chicken erythrocytes, calf thymus, and HeLa cells. We discuss prospects for profiling histone modifications for whole chromosomes from single cells.

  8. Microbial profile modification with spores

    SciTech Connect

    Bae, J.H.; Chambers, K.T.; Lee, H.O.

    1996-08-01

    To overcome the shortcomings of conventional, near-wellbore profile modification methods, a microbial profile modification (MPM) method with spores was investigated. A halotolerant, spore-forming mesophile was isolated and characterized. These biopolymer-producing spores propagate easily in Berea cores with permeabilities more than about 500 md. With a specifically formulated nutrient package, they are readily germinated and produce biofilm, which reduces the permeability of the rock. The depth of penetration and the degree of permeability reduction can be controlled by varying injection schemes.

  9. Constitutive expression of major histocompatibility complex class II antigens in pulmonary epithelium and endothelium varies among different species.

    PubMed

    Houser, Stuart L; Benjamin, Louis C; Wain, John C; Madsen, Joren C; Allan, James S

    2004-02-27

    We have observed high constitutive levels of class II antigen expression on porcine and human coronary endothelium, but not on the endothelium of rats and mice. This study examines whether a similar interspecies difference exists in the expression of class II molecules on pulmonary epithelium and endothelium. Lung tissues from naïve human, porcine, and rodent sources were stained with the monoclonal antibody ISCR3 and examined by light microscopy. Immunoperoxidase staining of class II molecules was observed on human and porcine pulmonary epithelium and endothelium, but was absent in rats and mice. By using an antibody with cross-species reactivity, we demonstrated that naïve swine pulmonary epithelium and endothelium, unlike those of rodent species, express basal levels of class II antigens in a manner similar to that observed in human lung tissue. These interspecies differences may explain experimental differences observed between murine and large-animal constructs. PMID:15084944

  10. The Octopamine Receptor OAMB Mediates Ovulation via Ca2+/Calmodulin-Dependent Protein Kinase II in the Drosophila Oviduct Epithelium

    PubMed Central

    Lee, Hyun-Gwan; Rohila, Suman; Han, Kyung-An

    2009-01-01

    Ovulation is an essential physiological process in sexual reproduction; however, the underlying cellular mechanisms are poorly understood. We have previously shown that OAMB, a Drosophila G-protein-coupled receptor for octopamine (the insect counterpart of mammalian norepinephrine), is required for ovulation induced upon mating. OAMB is expressed in the nervous and reproductive systems and has two isoforms (OAMB-AS and OAMB-K3) with distinct capacities to increase intracellular Ca2+ or intracellular Ca2+ and cAMP in vitro. Here, we investigated tissue specificity and intracellular signals required for OAMB's function in ovulation. Restricted OAMB expression in the adult oviduct epithelium, but not the nervous system, reinstated ovulation in oamb mutant females, in which either OAMB isoform was sufficient for the rescue. Consistently, strong immunoreactivities for both isoforms were observed in the wild-type oviduct epithelium. To delineate the cellular mechanism by which OAMB regulates ovulation, we explored protein kinases functionally interacting with OAMB by employing a new GAL4 driver with restricted expression in the oviduct epithelium. Conditional inhibition of Ca2+/Calmodulin-dependent protein kinase II (CaMKII), but not protein kinase A or C, in the oviduct epithelium inhibited ovulation. Moreover, constitutively active CaMKII, but not protein kinase A, expressed only in the adult oviduct epithelium fully rescued the oamb female's phenotype, demonstrating CaMKII as a major downstream molecule conveying the OAMB's ovulation signal. This is consistent with the ability of both OAMB isoforms, whose common intracellular signal in vitro is Ca2+, to reinstate ovulation in oamb females. These observations reveal the critical roles of the oviduct epithelium and its cellular components OAMB and CaMKII in ovulation. It is conceivable that the OAMB-mediated cellular activities stimulated upon mating are crucial for secretory activities suitable for egg transfer from

  11. 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.

  12. 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

  13. Development of the Olfactory Epithelium and Nasal Glands in TMEM16A-/- and TMEM16A+/+ Mice

    PubMed Central

    Maurya, Devendra Kumar; Henriques, Tiago; Marini, Monica; Pedemonte, Nicoletta; Galietta, Luis J. V.; Rock, Jason R.; Harfe, Brian D.; Menini, Anna

    2015-01-01

    TMEM16A/ANO1 is a calcium-activated chloride channel expressed in several types of epithelia and involved in various physiological processes, including proliferation and development. During mouse embryonic development, the expression of TMEM16A in the olfactory epithelium is dynamic. TMEM16A is expressed at the apical surface of the entire olfactory epithelium at embryonic day E12.5 while from E16.5 its expression is restricted to a region near the transition zone with the respiratory epithelium. To investigate whether TMEM16A plays a role in the development of the mouse olfactory epithelium, we obtained the first immunohistochemistry study comparing the morphological properties of the olfactory epithelium and nasal glands in TMEM16A-/- and TMEM16A+/+ littermate mice. A comparison between the expression of the olfactory marker protein and adenylyl cyclase III shows that genetic ablation of TMEM16A did not seem to affect the maturation of olfactory sensory neurons and their ciliary layer. As TMEM16A is expressed at the apical part of supporting cells and in their microvilli, we used ezrin and cytokeratin 8 as markers of microvilli and cell body of supporting cells, respectively, and found that morphology and development of supporting cells were similar in TMEM16A-/- and TMEM16A+/+ littermate mice. The average number of supporting cells, olfactory sensory neurons, horizontal and globose basal cells were not significantly different in the two types of mice. Moreover, we also observed that the morphology of Bowman’s glands, nasal septal glands and lateral nasal glands did not change in the absence of TMEM16A. Our results indicate that the development of mouse olfactory epithelium and nasal glands does not seem to be affected by the genetic ablation of TMEM16A. PMID:26067252

  14. 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

  15. 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…

  16. 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

  17. 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…

  18. 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)

  19. MODIFICATION OF CC WHITEFLY TRAPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modifications of CC whitefly traps are in progress to improve their potential for adult whitefly control in greenhouses. Adult catches in the modified CC traps have been increased by 50% by coating trap tops with Tanglefoot and removing the deflector plates. In laboratory studies, installation of ...

  20. 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.

  1. Behaviour modification in hyperactive children.

    PubMed

    Weeks, A; Laver-Bradbury, C

    Behaviour problems in pre-school children can be significantly improved by professionals experienced in child behaviour modification techniques. Reported disobedience, temper tantrums and poor concentration in hyperactive children aged three to three-and-a-half years improved significantly in a treatment group, following eight home visits by research health visitors working in a child and family guidance service. PMID:9418516

  2. Relative permeability of retina and retinal pigment epithelium to the diffusion of tritiated water from vitreous to choroid

    SciTech Connect

    Orr, G.; Goodnight, R.; Lean, J.S.

    1986-11-01

    The movement of intravitreally injected tritiated water from the vitreous to the choroid was accelerated by the removal of intervening retina. Both rate of transfer and peak choroidal levels of the tracer were increased, but the proportion of the intravitreal dose recovered was unaltered. In contrast, the movement of tritiated water after diffuse damage to the retinal pigment epithelium by sodium iodate was similar to that of control eyes. The main resistance to the diffusion of this tracer from the vitreous to the choroid is the retina. The differential permeability of the retina and the retinal pigment epithelium may have a role in normal retinal adhesion.

  3. Cytochrome P450 2A of nasal epithelium: regulation and role in carcinogen metabolism.

    PubMed

    Béréziat, J C; Raffalli, F; Schmezer, P; Frei, E; Geneste, O; Lang, M A

    1995-10-01

    In this study, we found that rat nasal coumarin-7-hydroxylase (COH) activity was two orders of magnitude higher than rat hepatic COH activity and could be induced by adding coumarin to the rats' drinking water. In western blot analysis, an anti-cytochrome P450 (Cyp) 2a-5 (mouse liver COH) antibody recognized a sharp band in the microsomal fraction of rat nasal epithelium but not of the liver; the band comigrated with Cyp2a-5. The intensity of the band was increased by the coumarin treatment. Similarly, in northern blot analysis, a cDNA probe specific for Cyp2a-5 recognized an mRNA in the nasal epithelium having the same size as mouse liver Cyp2a-5 mRNA; however, no hybridizable mRNA was recognized in liver preparations. Unlike the protein level, the level of the mRNA was not increased by coumarin. When northern blot analyses were performed with two oligoprobes specific for rat lung CYP2A3, an mRNA of similar size to Cyp2a-5 mRNA was recognized. In immunoinhibition analysis, anti-Cyp2a-5 antibody inhibited rat nasal COH activity and aflatoxin B1 (AFB1) metabolism completely. It inhibited N-nitrosodiethylamine (NDEA) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) metabolism by 80-90%. In contrast, the hepatic metabolism of the four compounds was not affected by the antibody. When coumarin instead of anti-Cyp2a-5 antibody was used, a strong but variable inhibition of the nasal metabolism of AFB1, NDEA, and NNK was seen. The results suggest that an enzyme or enzymes similar to mouse liver Cyp2a-5, one of which may be CYP2A3, is expressed at high levels in rat nasal epithelium but not in the liver and that its expression is increased by coumarin, an odorant and a substrate of Cyp2a-5. The increase probably occurs by protein stabilization or stimulation of translation. The results also show that the enzyme has a key role in the nasal metabolism of three well-known carcinogens, AFB1, NDEA, and NNK and may therefore be an important contributing factor in nasal

  4. 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

  5. Microscopic and ultrastructural modifications of postmenopausal atrophic vaginal mucosa after fractional carbon dioxide laser treatment.

    PubMed

    Zerbinati, Nicola; Serati, Maurizio; Origoni, Massimo; Candiani, Massimo; Iannitti, Tommaso; Salvatore, Stefano; Marotta, Francesco; Calligaro, Alberto

    2015-01-01

    Vaginal atrophy occurring during menopause is closely related to the dramatic decrease in ovarian estrogens due to the loss of follicular activity. Particularly, significant changes occur in the structure of the vaginal mucosa, with consequent impairment of many physiological functions. In this study, carried out on bioptic vaginal mucosa samples from postmenopausal, nonestrogenized women, we present microscopic and ultrastructural modifications of vaginal mucosa following fractional carbon dioxide (CO2) laser treatment. We observed the restoration of the vaginal thick squamous stratified epithelium with a significant storage of glycogen in the epithelial cells and a high degree of glycogen-rich shedding cells at the epithelial surface. Moreover, in the connective tissue constituting the lamina propria, active fibroblasts synthesized new components of the extracellular matrix including collagen and ground substance (extrafibrillar matrix) molecules. Differently from atrophic mucosa, newly-formed papillae of connective tissue indented in the epithelium and typical blood capillaries penetrating inside the papillae, were also observed. Our morphological findings support the effectiveness of fractional CO2 laser application for the restoration of vaginal mucosa structure and related physiological trophism. These findings clearly coupled with striking clinical relief from symptoms suffered by the patients before treatment. PMID:25410301

  6. 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

  7. Susceptibility of lung epithelium to neutrophil elastase: protection by native inhibitors

    PubMed Central

    Bingle, L.; Richards, R. J.; Fox, B.; Masek, L.; Guz, A.

    1997-01-01

    The development of emphysema is thought to be due to an imbalance of proteases (especially neutrophil elastase [NE]) and antiproteases with loosening of the respiratory epithelium as an early event. We investigated the effect of NE on respiratory epithelial cell adherence in vitro , in the presence of varying concentrations and combinations of native inhibitors, α-1-proteinase inhibitor (PI) and secretory leukoprotease inhibitor (SLPI). SLPI was two to 12 times more effective than PI at preventing the effects of NE, especially when enzyme:inhibitor ratios were almost equivalent. Even when the concentration of SLPI was only 10% of the total (as in normal peripheral lung secretions), it gave greater protection than PI alone. This suggests that SLPI plays an important role in controlling neutrophil elastaseinduced inflammation and tissue damage. PMID:18472869

  8. Potential therapeutic effects of pigment epithelium-derived factor for treatment of diabetic retinopathy.

    PubMed

    Liu, Xiao; Chen, Hui-Hui; Zhang, Li-Wei

    2013-01-01

    Diabetic retinopathy (DR), a major micro-vascular complication of diabetes, has emerged as a leading cause of visual impairment and blindness among working adults in the worldwide. The pathobiology of DR involves multiple molecular pathways and is characterized chronic neurovascular degeneration. Current approaches to prevent or to treat DR are still far from satisfactory. Therefore, it is important to develop new therapeutic strategies for the prevention and treatment to DR. Pigment epithelium-derived factor (PEDF), a 50-kDa secreted glycoprotein, has been described as a multi-functional protein. Some emerging evidences indicate that PEDF are able to target multiple pathways exerting neurotropic, neuroprotective, anti-angiogenic, antivasopermeability, anti-inflammation, anti-thrombogenic and anti-oxidative effects in DR. In this review, we addressed the functions of PEDF in different pathways, which could lead to potential therapeutics on the treatment to DR. PMID:23638428

  9. 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

  10. Sodium pump stimulation by oxytocin and cyclic AMP in the isolated epithelium of the frog skin.

    PubMed

    Aceves, J

    1977-11-23

    Activity of the Na pump was judged by Na extrusion in epithelial cells loaded with Na by a previous incubation in K-free solutions in the cold. Oxytocin significantly stimulated Na extrusion either at normal (3.5 mM) or low (0.25 mM) K in the medium. It was stimulated as well by cyclic AMP. Maximal concentrations of either agent caused about the same degree of stimulation. Addition of ouabain or removal of K prevented the action of both agents, but amiloride showed no effect at all. These results strongly suggest that, a) neurohypophyseal hormones not only increase Na entry across the mucosal barrier of the epithelium but they also stimulate the serosal Na pump, b) cyclic AMP not only mediates the action of neurohypophyseal hormones on Na and water permeability of the mucosal barrier, but it also mediates the action of the hormones on the Na pump of the serosal barrier. PMID:202919

  11. Gene Expression Profile of the Regeneration Epithelium during Axolotl Limb Regeneration

    PubMed Central

    Campbell, Leah J.; Suárez-Castillo, Edna C.; Ortiz-Zuazaga, Humberto; Knapp, Dunja; Tanaka, Elly M.; Crews, Craig M.

    2012-01-01

    Urodele amphibians are unique amongst adult vertebrates in their ability to regenerate missing limbs. The process of limb regeneration requires several key tissues including a regeneration-competent wound epidermis called the regeneration epithelium (RE). We used microarray analysis to profile gene expression of the RE in the axolotl, a Mexican salamander. A list of 125 genes and expressed sequence tags (ESTs) showed a ≥1.5 fold expression in the RE than in a wound epidermis covering a lateral cuff wound. A subset of the RE ESTs and genes were further characterized for expression level changes over the time-course of regeneration. This study provides the first large scale identification of specific gene expression in the RE. PMID:21648017

  12. A study of the rete testis epithelium in several wild birds.

    PubMed Central

    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. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:6706832

  13. Cell stress-regulated human major histocompatibility complex class I gene expressed in gastrointestinal epithelium.

    PubMed Central

    Groh, V; Bahram, S; Bauer, S; Herman, A; Beauchamp, M; Spies, T

    1996-01-01

    Conventional major histocompatibility complex (MHC) class I genes encode molecules that present intracellular peptide antigens to T cells. They are ubiquitously expressed and regulated by interferon gamma. Two highly divergent human MHC class I genes, MICA and MICB, are regulated by promoter heat shock elements similar to those of HSP70 genes. MICA encodes a cell surface glycoprotein, which is not associated with beta 2-microglobulin, is conformationally stable independent of conventional class I peptide ligands, and almost exclusively expressed in gastrointestinal epithelium. Thus, this MHC class I molecule may function as an indicator of cell stress and may be recognized by a subset of gut mucosal T cells in an unusual interaction. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8901601

  14. 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

  15. Clonal Dynamics Reveal Two Distinct Populations of Basal Cells in Slow-Turnover Airway Epithelium.

    PubMed

    Watson, Julie K; Rulands, Steffen; Wilkinson, Adam C; Wuidart, Aline; Ousset, Marielle; Van Keymeulen, Alexandra; Göttgens, Berthold; Blanpain, Cédric; Simons, Benjamin D; Rawlins, Emma L

    2015-07-01

    Epithelial lineages have been studied at cellular resolution in multiple organs that turn over rapidly. However, many epithelia, including those of the lung, liver, pancreas, and prostate, turn over slowly and may be regulated differently. We investigated the mouse tracheal epithelial lineage at homeostasis by using long-term clonal analysis and mathematical modeling. This pseudostratified epithelium contains basal cells and secretory and multiciliated luminal cells. Our analysis revealed that basal cells are heterogeneous, comprising approximately equal numbers of multipotent stem cells and committed precursors, which persist in the basal layer for 11 days before differentiating to luminal fate. We confirmed the molecular and functional differences within the basal population by using single-cell qRT-PCR and further lineage labeling. Additionally, we show that self-renewal of short-lived secretory cells is a feature of homeostasis. We have thus revealed early luminal commitment of cells that are morphologically indistinguishable from stem cells. PMID:26119728

  16. 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.

  17. 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

  18. Assays for the Antiangiogenic and Neurotrophic Serpin Pigment Epithelium-Derived Factor

    PubMed Central

    Subramanian, Preeti; Crawford, Susan E.; Becerra, S. Patricia

    2012-01-01

    Pigment epithelium-derived factor (PEDF) is a secreted serpin that exhibits a variety of interesting biological activities. The multifunctional PEDF has neurotrophic and antiangiogenic properties, and acts in retinal differentiation, survival, and maintenance. It is also antitumorigenic and antimetastatic, and has stem cell self-renewal properties. It is widely distributed in the human body and exists in abundance in the eye as a soluble extracellular glycoprotein. Its levels are altered in diseases characterized by retinopathies and angiogenesis. Its mechanisms of neuroprotection and angiogenesis are associated with receptor interactions at cell-surface interfaces and changes in protein expression. This serpin lacks demonstrable serine protease inhibitory activity, but has binding affinity to extracellular matrix components and cell-surface receptors. Here we describe purification protocols, methods to quantify PEDF, and determine interactions with specific molecules, as well as neurotrophic and angiogenesis assays for this multifunctional protein. PMID:21683255

  19. Cell Models to Study Regulation of Cell Transformation in Pathologies of Retinal Pigment Epithelium

    PubMed Central

    Kuznetsova, Alla V.; Aleksandrova, Maria A.

    2014-01-01

    The retinal pigment epithelium (RPE) plays a key role in the development of many eye diseases leading to visual impairment and even blindness. Cell culture models of pathological changes in the RPE make it possible to study factors responsible for these changes and signaling pathways coordinating cellular and molecular mechanisms of cell interactions under pathological conditions. Moreover, they give an opportunity to reveal target cells and develop effective specific treatment for degenerative and dystrophic diseases of the retina. In this review, data are presented on RPE cell sources for culture models, approaches to RPE cell culturing, phenotypic changes of RPE cells in vitro, the role of signal pathways, and possibilities for their regulation in pathological processes. PMID:25177495

  20. Pseudotumoral and Multiple Retinal Pigment Epithelium Proliferation in Vogt-Koyanagi-Harada Disease

    PubMed Central

    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

  1. Mucus altering agents as adjuncts for nonviral gene transfer to airway epithelium.

    PubMed

    Ferrari, S; Kitson, C; Farley, R; Steel, R; Marriott, C; Parkins, D A; Scarpa, M; Wainwright, B; Evans, M J; Colledge, W H; Geddes, D M; Alton, E W

    2001-09-01

    Nonviral vectors have been shown to be a safe and valid alternative to recombinant viruses for gene therapy of cystic fibrosis (CF). Nevertheless, gene transfer efficiency needs to be increased before clinical efficacy is likely in man. One barrier to increased efficacy is normal airway mucus. Using an ex vivo model of sheep tracheal epithelium, we show that this barrier can, in part, be overcome by treatment with the mucolytic agents, Nacystelyn or N-acetylcysteine using either a cationic lipid or a cationic polymer as the gene transfer agent. Further, in vivo application of either Nacystelyn or the anticholinergic glycopyrrolate, both clinically used agents, resulted in increased reporter gene expression in the mouse lung, but no significant correction of the bioelectric defect in CF null mice. These results, whilst unlikely to be sufficient in themselves to achieve clinically relevant gene therapy, may be a further useful step in the attainment of this goal. PMID:11571577

  2. Cell proliferation in the human mammary epithelium. Differential contribution by epithelial and myoepithelial cells.

    PubMed Central

    Joshi, K.; Smith, J. A.; Perusinghe, N.; Monoghan, P.

    1986-01-01

    The ductal system of the human breast consists of epithelial, myoepithelial, and basal clear cells. By labeling ducts and alveoli dissected from reduction mammoplasty specimens with 3H-thymidine in vitro and labeling human breast organoids xenografted in nude mice in vivo, it was found that cellular proliferation in the human breast is virtually confined to epithelial and basal clear cells. A pulse label of 3H-thymidine in organ culture explants was followed over a period of time, and it was found that myoepithelial cells originate from a precursor cell population within the mammary epithelium after a number of cell divisions. Myoepithelial cells were not seen to divide when fully mature. Images Figure 1 Figure 2 PMID:3740213

  3. Excess NF-κB induces ectopic odontogenesis in embryonic incisor epithelium.

    PubMed

    Blackburn, J; Kawasaki, K; Porntaveetus, T; Kawasaki, M; Otsuka-Tanaka, Y; Miake, Y; Ota, M S; Watanabe, M; Hishinuma, M; Nomoto, T; Oommen, S; Ghafoor, S; Harada, F; Nozawa-Inoue, K; Maeda, T; Peterková, R; Lesot, H; Inoue, J; Akiyama, T; Schmidt-Ullrich, R; Liu, B; Hu, Y; Page, A; Ramírez, Á; Sharpe, P T; Ohazama, A

    2015-01-01

    Nuclear factor kappa B (NF-κB) signaling plays critical roles in many physiological and pathological processes, including regulating organogenesis. Down-regulation of NF-κB signaling during development results in hypohidrotic ectodermal dysplasia. The roles of NF-κB signaling in tooth development, however, are not fully understood. We examined mice overexpressing IKKβ, an essential component of the NF-κB pathway, under keratin 5 promoter (K5-Ikkβ). K5-Ikkβ mice showed supernumerary incisors whose formation was accompanied by up-regulation of canonical Wnt signaling. Apoptosis that is normally observed in wild-type incisor epithelium was reduced in K5-Ikkβ mice. The supernumerary incisors in K5-Ikkβ mice were found to phenocopy extra incisors in mice with mutations of Wnt inhibitor, Wise. Excess NF-κB activity thus induces an ectopic odontogenesis program that is usually suppressed under physiological conditions. PMID:25376721

  4. Study of Pigment Epithelium-derived Factor in Pathogenesis of Diabetic Retinopathy.

    PubMed

    Zang, Jing; Guan, Guoqi

    2015-06-01

    Diabetic retinopathy (DR), a major microvascular complication of diabetes, has emerged as a leading cause of visual impairment and blindness among adults worldwide. However, aside from pathological damage, the traditional laser and multi-needle operation treatments required for more advanced disease can cause further damage to the visual field and increase the operation risk. Therefore, the development of new therapeutic strategies for the prevention and treatment of DR is essential. Some emerging evidence now indicates that pigment epithelium-derived factor (PEDF), a multifunctional protein, can target multiple pathways to exert neurotropic, neuropro- tective, anti-angiogenic, anti-vasopermeability, anti-inflammation, anti-thrombogenic, and anti-oxidative effects against DR. This review addresses the functions of PEDF in different pathways that could lead to potential therapeutics for the treatment of DR. PMID:26902068

  5. [Electron microscopic studies of the gill epithelium of the amphibian teleost Periophthalmus vulgaris].

    PubMed

    Welsch, U; Storch, V

    1976-01-01

    The gill epithelium of the airdwelling fish Periophthalmus vulgaris has been studied with the electron microscope. The following celltypes can be distinguished: flat covering epithelial cells, chloride cells, mucous cells, basal cells, various leucocytes as well as a specific granule containing cell which is possibly an epithelial cell. The covering epithelial cells exhibit a relatively smooth apical surface and contain in their apical half densely packed microfilaments, pinocytotic vesicles are rare. These characteristics are not to be found in water dwelling fish and possibly represent adaptations to the air containing surroundings. In the chloride cells are numerous, especially in the basal halves of the secondary lamellae. The distal parts of the secondary lamellae the barrier for the respiratory gases measures about 0,9 micrometer. The basal cells are ribosome rich replacement cells. Two types of mucous cells occur. Individual intraepithelial nerve fibres have been observed. PMID:1036346

  6. 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.

  7. Disruption of retinoblastoma protein expression in the intestinal epithelium impairs lipid absorption.

    PubMed

    Choi, Pamela M; Guo, Jun; Erwin, Christopher R; Wandu, Wambui S; Leinicke, Jennifer A; Xie, Yan; Davidson, Nicholas O; Warner, Brad W

    2014-05-15

    We previously demonstrated increased villus height following genetic deletion, or knockout, of retinoblastoma protein (Rb) in the intestinal epithelium (Rb-IKO). Here we determined the functional consequences of augmented mucosal growth on intestinal fat absorption and following a 50% small bowel resection (SBR). Mice with constitutively disrupted Rb expression in the intestinal epithelium (Rb-IKO) along with their floxed (wild-type, WT) littermates were placed on a high-fat diet (HFD, 42% kcal fat) for 54 wk. Mice were weighed weekly, and fat absorption, indirect calorimetry, and MRI body composition were measured. Rb-IKO mice were also subjected to a 50% SBR, followed by HFD feeding for 33 wk. In separate experiments, we examined intestinal fat absorption in mice with conditional (tamoxifen-inducible) intestinal Rb (inducible Rb-IKO) deletion. Microarray revealed that the transcriptional expression of lipid absorption/transport genes was significantly reduced in constitutive Rb-IKO mice. These mice demonstrated greater mucosal surface area yet manifested paradoxically impaired intestinal long-chain triglyceride absorption and decreased cholesterol absorption. Despite attenuated lipid absorption, there were no differences in metabolic rate, body composition, and weight gain in Rb-IKO and WT mice at baseline and following SBR. We also confirmed fat malabsorption in inducible Rb-IKO mice. We concluded that, despite an expanded mucosal surface area, Rb-IKO mice demonstrate impaired lipid absorption without compensatory alterations in energy homeostasis or body composition. These findings underscore the importance of delineating structural/functional relationships in the gut and suggest a previously unknown role for Rb in the regulation of intestinal lipid absorption. PMID:24742992

  8. Gene expression in bovine rumen epithelium during weaning identifies molecular regulators of rumen development and growth.

    PubMed

    Connor, Erin E; Baldwin, Ransom L; Li, Cong-jun; Li, Robert W; Chung, Hoyoung

    2013-03-01

    During weaning, epithelial cell function in the rumen transitions in response to conversion from a pre-ruminant to a true ruminant environment to ensure efficient nutrient absorption and metabolism. To identify gene networks affected by weaning in bovine rumen, Holstein bull calves were fed commercial milk replacer only (MRO) until 42 days of age, then were provided diets of either milk + orchardgrass hay (MH) or milk + grain-based calf starter (MG). Rumen epithelial RNA was extracted from calves sacrificed at four time points: day 14 (n = 3) and day 42 (n = 3) of age while fed the MRO diet and day 56 (n = 3/diet) and day 70 (n = 3/diet) while fed the MH and MG diets for transcript profiling by microarray hybridization. Five two-group comparisons were made using Permutation Analysis of Differential Expression® to identify differentially expressed genes over time and developmental stage between days 14 and 42 within the MRO diet, between day 42 on the MRO diet and day 56 on the MG or MH diets, and between the MG and MH diets at days 56 and 70. Ingenuity Pathway Analysis (IPA) of differentially expressed genes during weaning indicated the top 5 gene networks involving molecules participating in lipid metabolism, cell morphology and death, cellular growth and proliferation, molecular transport, and the cell cycle. Putative genes functioning in the establishment of the rumen microbial population and associated rumen epithelial inflammation during weaning were identified. Activation of transcription factor PPAR-α was identified by IPA software as an important regulator of molecular changes in rumen epithelium that function in papillary development and fatty acid oxidation during the transition from pre-rumination to rumination. Thus, molecular markers of rumen development and gene networks regulating differentiation and growth of rumen epithelium were identified for selecting targets and methods for improving and assessing rumen development and

  9. MicroRNA Expression Differentiates Squamous Epithelium from Barrett’s Esophagus and Esophageal Cancer

    PubMed Central

    Garman, Katherine S.; Owzar, Kouros; Hauser, Elizabeth R.; Westfall, Kristen; Anderson, Blair R.; Souza, Rhonda F.; Diehl, Anna Mae; Provenzale, Dawn; Shaheen, Nicholas J.

    2013-01-01

    Background Current strategies fail to identify most patients with esophageal adenocarcinoma (EAC) before the disease becomes advanced and incurable. Given the dismal prognosis associated with EAC, improvements in detection of early-stage esophageal neoplasia are needed. Aims We sought to assess whether differential expression of microRNAs could discriminate between squamous epithelium, Barrett’s esophagus (BE), and EAC. Methods We analyzed microRNA expression in a discovery cohort of human endoscopic biopsy samples from 36 patients representing normal squamous esophagus (n=11), BE (n=14), and high-grade dysplasia (HGD)/EAC (n=11). RNA was assessed using microarrays representing 847 human microRNAs followed by qRT-PCR verification of nine microRNAs. In a second cohort (n=18), qRT-PCR validation of five miRNAs was performed. Expression of 59 microRNAs associated with BE/EAC in the literature was assessed in our training cohort. Known esophageal cell lines were used to compare miRNA expression to tissue miRNAs. Results After controlling for multiple comparisons, we found 34 miRNAs differentially expressed between squamous esophagus and BE/EAC by microarray analysis. However, miRNA expression did not reliably differentiate non-dysplastic BE from EAC. In the validation cohort, all five microRNAs selected for qRT-PCR validation differentiated between squamous samples and BE/EAC. Microarray results supported 14 of the previously reported microRNAs associated with BE/EAC in the literature. Cell lines did not generally reflect miRNA expression found in vivo. Conclusions These data indicate that miRNAs differ between squamous esophageal epithelium and BE/EAC, but do not distinguish between BE and EAC. We suggest prospective evaluation of miRNAs in patients at high risk for EAC. PMID:23925817

  10. In GERD patients, mucosal repair associated genes are upregulated in non-inflamed oesophageal epithelium

    PubMed Central

    De Vries, D R; Ter Linde, J J M; Van Herwaarden, M A; Schwartz, M P; Shephard, P; Geng, M M; Smout, A J P M; Samsom, M

    2009-01-01

    Abstract Previous studies addressing the effects of acid reflux and PPI therapy on gene expression in oesophageal epithelium concentrated on inflamed tissue. We aimed to determine changes in gene expression in non-inflamed oesophageal epithelium of GERD patients. Therefore, we included 20 GERD patients with pathological total 24-hr acid exposure of 6–12% and SAP ≥ 95%. Ten patients discontinued PPI treatment (PPI-), 10 took pantoprazole 40 mg bid (PPI+). Ten age/sex-matched healthy controls were recruited. Biopsies were taken from non-inflamed mucosa 6 cm and 16 cm proximal to the squamocolumnar junction (SCJ). Gene expression profiling of biopsies from 6 cm was performed on Human Genome U133 Plus 2.0 arrays (Affymetrix). Genes exhibiting a fold change >1.4 (t-test P-value < 1E– 4) were considered differentially expressed. Results were confirmed by real-time RT-PCR. In PPI- patients, 92 microarray probesets were deregulated. The majority of the corresponding genes were associated with cell–cell contacts, cytoskeletal reorganization and cellular motility, suggesting facilitation of a migratory phenotype. Genes encoding proteins with anti-apoptotic or anti-proliferative functions or stress-protective functions were also deregulated. No probesets were deregulated in PPI+ patients. QPCR analysis of 20 selected genes confirmed most of the deregulations in PPI- patients, and showed several deregulated genes in PPI+ patients as well. In the biopsies taken at 16 cm QPCR revealed no deregulations of the selected genes. We conclude that upon acid exposure, oesophageal epithelial cells activate a process globally known as epithelial restitution: up-regulation of anti-apoptotic, anti-oxidant and migration associated genes. Possibly this process helps maintaining barrier function. PMID:19413890

  11. Identification and molecular regulation of neural stem cells in the olfactory epithelium

    SciTech Connect

    Beites, Crestina L.; Kawauchi, Shimako; Crocker, Candice E.; Calof, Anne L. . E-mail: alcalof@uci.edu

    2005-06-10

    The sensory neurons that subserve olfaction, olfactory receptor neurons (ORNs), are regenerated throughout life, making the neuroepithelium in which they reside [the olfactory epithelium (OE)] an excellent model for studying how intrinsic and extrinsic factors regulate stem cell dynamics and neurogenesis during development and regeneration. Numerous studies indicate that transcription factors and signaling molecules together regulate generation of ORNs from stem and progenitor cells during development, and work on regenerative neurogenesis indicates that these same factors may operate at postnatal ages as well. This review describes our current knowledge of the identity of the OE neural stem cell; the different cell types that are thought to be the progeny (directly or indirectly) of this stem cell; and the factors that influence cell differentiation in the OE neuronal lineage. We review data suggesting that (1) the ORN lineage contains three distinct proliferating cell types-a stem cell and two populations of transit amplifying cells; (2) in established OE, these three cell types are present within the basal cell compartment of the epithelium; and (3) the stem cell that gives rise ultimately to ORNs may also generate two glial cell types of the primary olfactory pathway: sustentacular cells (SUS), which lie within OE proper; and olfactory ensheathing cells (OEC), which envelope the olfactory nerve. In addition, we describe factors that are both made by and found within the microenvironment of OE stem and progenitor cells, and which exert crucial growth regulatory effects on these cells. Thus, as with other regenerating tissues, the basis of regeneration in the OE appears be a population of stem cells, which resides within a microenvironment (niche) consisting of factors crucial for maintenance of its capacity for proliferation and differentiation.

  12. Primary Cilia on Horizontal Basal Cells Regulate Regeneration of the Olfactory Epithelium

    PubMed Central

    Joiner, Ariell M.; Green, Warren W.; McIntyre, Jeremy C.; Allen, Benjamin L.; Schwob, James E.

    2015-01-01

    The olfactory epithelium (OE) is one of the few tissues to undergo constitutive neurogenesis throughout the mammalian lifespan. It is composed of multiple cell types including olfactory sensory neurons (OSNs) that are readily replaced by two populations of basal stem cells, frequently dividing globose basal cells and quiescent horizontal basal cells (HBCs). However, the precise mechanisms by which these cells mediate OE regeneration are unclear. Here, we show for the first time that the HBC subpopulation of basal stem cells uniquely possesses primary cilia that are aligned in an apical orientation in direct apposition to sustentacular cell end feet. The positioning of these cilia suggests that they function in the detection of growth signals and/or differentiation cues. To test this idea, we generated an inducible, cell type-specific Ift88 knock-out mouse line (K5rtTA;tetOCre;Ift88fl/fl) to disrupt cilia formation and maintenance specifically in HBCs. Surprisingly, the loss of HBC cilia did not affect the maintenance of the adult OE but dramatically impaired the regeneration of OSNs following lesion. Furthermore, the loss of cilia during development resulted in a region-specific decrease in neurogenesis, implicating HBCs in the establishment of the OE. Together, these results suggest a novel role for primary cilia in HBC activation, proliferation, and differentiation. SIGNIFICANCE STATEMENT We show for the first time the presence of primary cilia on a quiescent population of basal stem cells, the horizontal basal cells (HBCs), in the olfactory epithelium (OE). Importantly, our data demonstrate that cilia on HBCs are necessary for regeneration of the OE following injury. Moreover, the disruption of HBC cilia alters neurogenesis during the development of the OE, providing evidence that HBCs participate in the establishment of this tissue. These data suggest that the mechanisms of penetrance for ciliopathies in the OE extend beyond that of defects in olfactory sensory

  13. [Large intestinal epithelium and short-chain fatty acids. Expected, unexpected, unexplained findings].

    PubMed

    von Engelhardt, W

    2005-11-01

    Short-chain fatty acids (SCFA) are present in hindgut contents in high concentrations. SCFA are generated and also absorbed rapidly in the large intestine. Absorption results from diffusion of the undissociated and lipid soluble form or in exchange for bicarbonate. The controversial concepts concerning the extent of diffusion or the exchange for bicarbonate are partly due to contradictory findings and unequal mechanisms in different species and in different segments of the large intestine as well as in the different methods used. An almost neutral pH microclimate at the luminal surface is of importance for absorption of SCFA. The apical membranes of the epithelial cells in caecum and in proximal colon of guinea pigs are an substantial barrier for the diffusion of SCFA. After withdrawal of butyrate for only one hour from the perfusion or incubation solutions a massive apoptosis had been observed during the in situ perfusion of segments of guinea pig large intestine and also in in vitro studies with isolated epithelia in Ussing-chambers. In vitro apoptotic bodies and cells are emitted at the epithelial surface. However, in vivo induced by butyrate deprivation resident macrophages were tightly clustered below the surface epithelium. Aided by cytoplasmatic projections these macrophages phagocytose and transport apoptotic material from the epithelial intercellular spaces into their bodies. Obviously macrophages can be overloaded by this massive apoptosis, and some of the undigested apoptotic fragments are emitted into the lamina propria. Formation of a colitis ulcerosa may originate from these released undigested apoptotic bodies. Furthermore hints indicate aetiological interrelations between deprivation of butyrate and colon cancer. Butyrate-paradox denotes the contrarian effects on apoptosis and cell proliferation after addition or deprivation of butyrate in cultures of large intestinal tumour-cell-lines in comparison with the healthy, intact epithelium. PMID:16366035

  14. Effect of resistant starch on genotoxin-induced apoptosis, colonic epithelium, and lumenal contents in rats.

    PubMed

    Le Leu, Richard K; Brown, Ian L; Hu, Ying; Young, Graeme P

    2003-08-01

    The effect of different doses of a type-2 resistant starch (RS) in the form of high amylose cornstarch (HAS) on the intralumenal environment and the acute-apoptotic response to a genotoxic carcinogen (AARGC) in the colon was assessed to determine if changes in lumenal conditions were associated with an enhanced apoptotic response to DNA damage. The control diet was a modified form of the AIN-76 diet containing fully digestible starch but no dietary fibre. HAS was added to the control diet at the expense of digestible starch to give 10% HAS, 20% HAS and 30% HAS. Rats were fed the different experimental diets for a period of 4 weeks, after which a single injection of azoxymethane was given to induce DNA damage in the colonic epithelium; 6 h later AARGC was measured. Other measures included fecal and cecal short chain fatty acids (SCFA) and pH, and cell proliferation in the colonic epithelium. In HAS-supplemented rats, fermentation events were significantly increased in both cecum and feces. There was a progressive decrease in pH in both the cecum and feces as the amount of HAS in the diet increased. SCFA concentrations, including butyrate, were significantly elevated by HAS with higher levels being observed in the cecum than in the feces. There was a significant increase in colonic AARGC with HAS doses of 20 and 30% (P < 0.01) but not with 10% HAS. Cell proliferation was not affected by any dose of HAS. Correlations with AARGC, independent of dietary group, were seen for fecal SCFAs and pH, suggesting that fermentation events, might explain the effect of RS on AARGC. Altering amounts of dietary RS changes fermentative activity in the colon. Increased RS is associated with enhanced AARGC. Changes in amount of fermentable substrate are capable of changing the biological response to DNA damage. PMID:12807738

  15. Apical electrolyte concentration modulates barrier function and tight junction protein localization in bovine mammary epithelium.

    PubMed

    Quesnell, Rebecca R; Erickson, Jamie; Schultz, Bruce D

    2007-01-01

    In vitro mammary epithelial cell models typically fail to form a consistently tight barrier that can effectively separate blood from milk. Our hypothesis was that mammary epithelial barrier function would be affected by changes in luminal ion concentration and inflammatory cytokines. Bovine mammary epithelial (BME-UV cell line) cells were grown to confluence on permeable supports with a standard basolateral medium and either high-electrolyte (H-elec) or low-electrolyte (L-elec) apical medium for 14 days. Apical media were changed to/from H-elec medium at predetermined times prior to assay. Transepithelial electrical resistance (R(te)) was highest in monolayers continuously exposed to apical L-elec. A time-dependent decline in R(te) began within 24 h of H-elec medium exposure. Change from H-elec medium to L-elec medium time-dependently increased R(te). Permeation by FITC-conjugated dextran was elevated across monolayers exposed to H-elec, suggesting compromise of a paracellular pathway. Significant alteration in occludin distribution was evident, concomitant with the changes in R(te), although total occludin was unchanged. Neither substitution of Na(+) with N-methyl-d-glucosamine (NMDG(+)) nor pharmacological inhibition of transcellular Na(+) transport pathways abrogated the effects of apical H-elec medium on R(te). Tumor necrosis factor alpha, but not interleukin-1beta nor interleukin-6, in the apical compartment caused a significant decrease in R(te) within 8 h. These results indicate that mammary epithelium is a dynamic barrier whose cell-cell contacts are acutely modulated by cytokines and luminal electrolyte environment. Results not only demonstrate that BME-UV cells are a model system representative of mammary epithelium but also provide critical information that can be applied to other mammary model systems to improve their physiological relevance. PMID:16885391

  16. A novel interleukin 33/ST2 signaling regulates inflammatory response in human corneal epithelium.

    PubMed

    Lin, Jing; Zhang, Lili; Zhao, Guiqiu; Su, Zhitao; Deng, Ruzhi; Pflugfelder, Stephen C; Li, De-Quan

    2013-01-01

    Interleukin (IL) 33, a member of IL-1 cytokine family, is well known to promote Th2 type immune responses by signaling through its receptor ST2. However, it is not clear whether ST2 is expressed by mucosal epithelium, and how it responds to IL-33 to induce inflammatory mediators. This study was to identify the presence and function of ST2 and explore the role of IL-33/ST2 signaling in regulating the inflammatory cytokine production in corneal epithelial cells. Human corneal tissues and cultured primary human corneal epithelial cells (HCECs) were treated with IL-33 in different concentrations without or with different inhibitors to evaluate the expression, location and signaling pathways of ST2 in regulating production of inflammatory cytokine and chemokine. The mRNA expression was determined by reverse transcription and real time PCR, and protein production was measured by enzyme-linked immunosorbent assay (ELISA), immunohistochemical and immunofluorescent staining. ST2 mRNA and protein were detected in donor corneal epithelium and cultured HCECs, and ST2 signal was enhanced by exposure to IL-33. IL-33 significantly stimulated the production of inflammatory cytokines (TNF-α, IL-1β and IL-6) and chemokine IL-8 by HCECs at both mRNA and protein levels. The stimulated production of inflammatory mediators by IL-33 was blocked by ST2 antibody or soluble ST2 protein. Interestingly, the IκB-α inhibitor BAY11-7082 or NF-κB activation inhibitor quinazoline blocked NF-κB p65 protein phosphorylation and nuclear translocation, and also suppressed the production of these inflammatory cytokines and chemokine induced by IL-33. These findings demonstrate that ST2 is present in human corneal epithelial cells, and IL-33/ST2 signaling plays an important role in regulating IL-33 induced inflammatory responses in ocular surface. PMID:23585867

  17. A Novel Interleukin 33/ST2 Signaling Regulates Inflammatory Response in Human Corneal Epithelium

    PubMed Central

    Lin, Jing; Zhang, Lili; Zhao, Guiqiu; Su, Zhitao; Deng, Ruzhi; Pflugfelder, Stephen C.; Li, De-Quan

    2013-01-01

    Interleukin (IL) 33, a member of IL-1 cytokine family, is well known to promote Th2 type immune responses by signaling through its receptor ST2. However, it is not clear whether ST2 is expressed by mucosal epithelium, and how it responds to IL-33 to induce inflammatory mediators. This study was to identify the presence and function of ST2 and explore the role of IL-33/ST2 signaling in regulating the inflammatory cytokine production in corneal epithelial cells. Human corneal tissues and cultured primary human corneal epithelial cells (HCECs) were treated with IL-33 in different concentrations without or with different inhibitors to evaluate the expression, location and signaling pathways of ST2 in regulating production of inflammatory cytokine and chemokine. The mRNA expression was determined by reverse transcription and real time PCR, and protein production was measured by enzyme-linked immunosorbent assay (ELISA), immunohistochemical and immunofluorescent staining. ST2 mRNA and protein were detected in donor corneal epithelium and cultured HCECs, and ST2 signal was enhanced by exposure to IL-33. IL-33 significantly stimulated the production of inflammatory cytokines (TNF-α, IL-1β and IL-6) and chemokine IL-8 by HCECs at both mRNA and protein levels. The stimulated production of inflammatory mediators by IL-33 was blocked by ST2 antibody or soluble ST2 protein. Interestingly, the IκB-α inhibitor BAY11-7082 or NF-κB activation inhibitor quinazoline blocked NF-κB p65 protein phosphorylation and nuclear translocation, and also suppressed the production of these inflammatory cytokines and chemokine induced by IL-33. These findings demonstrate that ST2 is present in human corneal epithelial cells, and IL-33/ST2 signaling plays an important role in regulating IL-33 induced inflammatory responses in ocular surface. PMID:23585867

  18. Translocation of 40 nm diameter nanowires through the intestinal epithelium of Daphnia magna

    PubMed Central

    Mattsson, Karin; Adolfsson, Karl; Ekvall, Mikael T.; Borgström, Magnus T.; Linse, Sara; Hansson, Lars-Anders; Cedervall, Tommy; Prinz, Christelle N.

    2016-01-01

    Abstract Nanowires (NWs) have unique electrical and optical properties of value for many applications including lighting, sensing, and energy harnessing. Consumer products containing NWs increase the risk of NWs being released in the environment, especially into aquatic ecosystems through sewage systems. Daphnia magna is a common, cosmopolitan freshwater organism sensitive to toxicity tests and represents a likely entry point for nanoparticles into food webs of aquatic ecosystems. Here we have evaluated the effect of NW diameter on the gut penetrance of NWs in Daphnia magna. The animals were exposed to NWs of two diameters (40 and 80 nm) and similar length (3.6 and 3.8 μm, respectively) suspended in water. In order to locate the NWs in Daphnia, the NWs were designed to comprise one inherently fluorescent segment of gallium indium phosphide (GaInP) flanked by a gallium phosphide (GaP) segment. Daphnia mortality was assessed directly after 24 h of exposure and 7 days after exposure. Translocation of NWs across the intestinal epithelium was investigated using confocal fluorescence microscopy directly after 24 h of exposure and was observed in 89% of Daphnia exposed to 40 nm NWs and in 11% of Daphnia exposed to 80 nm NWs. A high degree of fragmentation was observed for NWs of both diameters after ingestion by the Daphnia, although 40 nm NWs were fragmented to a greater extent, which could possibly facilitate translocation across the intestinal epithelium. Our results show that the feeding behavior of animals may enhance the ability of NWs to penetrate biological barriers and that penetrance is governed by the NW diameter. PMID:27181920

  19. Translocation of 40 nm diameter nanowires through the intestinal epithelium of Daphnia magna.

    PubMed

    Mattsson, Karin; Adolfsson, Karl; Ekvall, Mikael T; Borgström, Magnus T; Linse, Sara; Hansson, Lars-Anders; Cedervall, Tommy; Prinz, Christelle N

    2016-10-01

    Nanowires (NWs) have unique electrical and optical properties of value for many applications including lighting, sensing, and energy harnessing. Consumer products containing NWs increase the risk of NWs being released in the environment, especially into aquatic ecosystems through sewage systems. Daphnia magna is a common, cosmopolitan freshwater organism sensitive to toxicity tests and represents a likely entry point for nanoparticles into food webs of aquatic ecosystems. Here we have evaluated the effect of NW diameter on the gut penetrance of NWs in Daphnia magna. The animals were exposed to NWs of two diameters (40 and 80 nm) and similar length (3.6 and 3.8 μm, respectively) suspended in water. In order to locate the NWs in Daphnia, the NWs were designed to comprise one inherently fluorescent segment of gallium indium phosphide (GaInP) flanked by a gallium phosphide (GaP) segment. Daphnia mortality was assessed directly after 24 h of exposure and 7 days after exposure. Translocation of NWs across the intestinal epithelium was investigated using confocal fluorescence microscopy directly after 24 h of exposure and was observed in 89% of Daphnia exposed to 40 nm NWs and in 11% of Daphnia exposed to 80 nm NWs. A high degree of fragmentation was observed for NWs of both diameters after ingestion by the Daphnia, although 40 nm NWs were fragmented to a greater extent, which could possibly facilitate translocation across the intestinal epithelium. Our results show that the feeding behavior of animals may enhance the ability of NWs to penetrate biological barriers and that penetrance is governed by the NW diameter. PMID:27181920

  20. Changes in the oviducal epithelium during the estrous cycle in the marsupial Monodelphis domestica

    PubMed Central

    Kress, Annetrudi; Morson, Gianni

    2007-01-01

    The Monodelphis oviduct can be divided into four anatomical segments: preampulla (comprising fimbriae and infundibulum), ampulla, isthmus with crypts and uterotubal junction. Ovaries are enclosed in a periovarial sac, the bursa, and in some specimens tubules of an epoophoron could be identified. In both structures non-ciliated cells develop small translucent vesicles, which accumulate in the cell apices and presumably produce fluid as often seen in the bursa and in the tubules of the epooophoron. These vesicles do not stain with Alcian blue or PAS. The same applies also to the non-ciliated cells of the fimbriae. The oviducal epithelium of ampulla and the surface epithelium of the isthmus consisting of ciliated and non-ciliated, secretory cells undergo considerable changes during the estrous cycle. Proestrus shows low numbers of ciliated cells, some are in the process of neo-ciliogenesis, non-ciliated cells carry solitary cilia and few remnant secretory granules from the previous cycle may be found. At estrus the amount of ciliated cells in ampulla and isthmus has increased, most non-cililated cells lost the solitary cilia, developed longer microvilli and formed numerous secretory granules in their cell apices. At postestrus secretory products, often surrounded by membranes, are extruded into the oviducal lumen and contribute towards egg coat formation. First signs of deciliation processes are apparent. Solitary cilia reappear. At metestrus only few secretory cells are left with some secretory material. The lumen is often filled with shed cilia and cell apices. Proliferation of basal bodies within non-secretory cells indicate the formation of new ciliated cells. The non-ciliated epithelial cells of the isthmic crypts form no secretory granules but accumulate a great number of translucent vesicles, which in contrast to the secretory granules do not stain with Alcian blue or PAS. PMID:17883438

  1. Expression of S100B during the innate immune of corneal epithelium against fungi invasion

    PubMed Central

    Zhang, Jie; Zhao, Gui-Qiu; Qu, Jing; Che, Cheng-Ye; Lin, Jing; Jiang, Nan; Zhao, Han; Wang, Xue-Jun

    2016-01-01

    AIM To explore the expression of S100B in corneal epithelial cells under Aspergillus stimulation both in vivo and in vitro. METHODS Immortalized human corneal epithelial cells (HCECs) were exposed to inactive Aspergillus fumigatus (A. fumigatus) conidia at 0, 4, 8, 12, 16, and 24h respectively. The corneas of Wistar rats were exposed to active A. fumigatus at 0, 12, 24, 48h and the normal rat corneas were used for normal control. The mRNA level of S100B was evaluated by real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). S100B protein expression in cornea epithelium was detected by immunohistochemical/immunocytochemical staining (IHC/ICC). RESULTS Histopathology revealed a significant inflammatory cell infiltration in fungal keratitis human and rat cornea. Corneal epithelial cells didn't express or rarely express S100B at baseline. A. fumigatus significantly induced S100B mRNA expression in cultured corneal epithelial cells in a time depended manner in vitro, the mRNA began to rise significantly at 8h in vitro (P<0.05) and continue to rise as time prolonged (P<0.01). In vivo, S100B mRNA level was low in the normal corneas. However, it was increased in keratitis corneas from 12h after infection (P<0.05) and reached to a peak at 24h (P<0.001). Immunochemistry revealed an obvious staining in fungal keratitis corneas as well as immortalized HCECs compared to the normal ones respectively, indicating an increased expression of S100B protein. CONCLUSION S100B exists in corneal epithelial cells and is over-expressed under A. fumigatus stimulation. S100B may play an important role in the innate immune response of the corneal epithelium during A. fumigatus infection. PMID:26949634

  2. Hypoxia/Reoxygenation Effects on Ion Transport across Rat Colonic Epithelium

    PubMed Central

    Schindele, Sabine; Pouokam, Ervice; Diener, Martin

    2016-01-01

    Ischemia causes severe damage in the gastrointestinal tract. Therefore, it is interesting to study how the barrier and transport functions of intestinal epithelium change under hypoxia and subsequent reoxygenation. For this purpose we simulated hypoxia and reoxygenation on mucosa-submucosa preparations from rat distal colon in Ussing chambers and on isolated crypts. Hypoxia (N2 gassing for 15 min) induced a triphasic change in short-circuit current (Isc): a transient decrease, an increase and finally a long-lasting fall below the initial baseline. During the subsequent reoxygenation phase, Isc slightly rose to values above the initial baseline. Tissue conductance (Gt) showed a biphasic increase during both the hypoxia and the reoxygenation phases. Omission of Cl− or preincubation of the tissue with transport inhibitors revealed that the observed changes in Isc represented changes in Cl− secretion. The radical scavenger trolox C reduced the Isc response during hypoxia, but failed to prevent the rise of Isc during reoxygenation. All changes in Isc were Ca2+-dependent. Fura-2 experiments at loaded isolated colonic crypts revealed a slow increase of the cytosolic Ca2+ concentration during hypoxia and the reoxygenation phase, mainly caused by an influx of extracellular Ca2+. Surprisingly, no changes could be detected in the fluorescence of the superoxide anion-sensitive dye mitosox or the thiol-sensitive dye thiol tracker, suggesting a relative high capacity of the colonic epithelium (with its low O2 partial pressure even under physiological conditions) to deal with enhanced radical production during hypoxia/reoxygenation. PMID:27445839

  3. Fgf10 is required for specification of non-sensory regions of the cochlear epithelium

    PubMed Central

    Urness, Lisa D.; Wang, Xiaofen; Shibata, Shumei; Ohyama, Takahiro; Mansour, Suzanne L.

    2015-01-01

    The vertebrate inner ear is a morphologically complex sensory organ comprised of two compartments, the dorsal vestibular apparatus and the ventral cochlear duct, required for motion and sound detection, respectively. Fgf10, in addition to Fgf3, is necessary for the earliest stage of otic placode induction, but continued expression of Fgf10 in the developing otic epithelium, including the prosensory domain and later in Kolliker’s organ, suggests additional roles for this gene during morphogenesis of the labyrinth. While loss of Fgf10 was implicated previously in semicircular canal agenesis, we show that Fgf10−/+ embryos also exhibit a reduction or absence of the posterior semicircular canal, revealing a dosage-sensitive requirement for FGF10 in vestibular development. In addition, we show that Fgf10−/− embryos have previously unappreciated defects of cochlear morphogenesis, including a somewhat shortened duct, and, surprisingly, a substantially narrower duct. The mutant cochlear epithelium lacks Reissner’s membrane and a large portion of the outer sulcus--two non-contiguous, non-sensory domains. Marker gene analyses revealed effects on Reissner’s membrane as early as E12.5–E13.5 and on the outer sulcus by E15.5, stages when Fgf10 is expressed in close proximity to Fgfr2b, but these effects were not accompanied by changes in epithelial cell proliferation or death. These data indicate a dual role for Fgf10 in cochlear development: to regulate outgrowth of the duct and subsequently as a bidirectional signal that sequentially specifies Reissner’s membrane and outer sulcus non-sensory domains. These findings may help to explain the hearing loss sometimes observed in LADD syndrome subjects with FGF10 mutations. PMID:25624266

  4. Cyclophilin A is a new M cell marker of bovine intestinal epithelium.

    PubMed

    Hondo, Tetsuya; Someya, Shunsuke; Nagasawa, Yuya; Terada, Shunsuke; Watanabe, Hitoshi; Chen, Xiangning; Watanabe, Kouichi; Ohwada, Shyuichi; Kitazawa, Haruki; Rose, Michael T; Nochi, Tomonori; Aso, Hisashi

    2016-06-01

    Microfold (M) cells in the follicle-associated epithelium (FAE) of Peyer's patches contribute to the mucosal immune response by the transcytosis of microorganisms. The mechanism by which M cells take up microorganisms, and the functional proteins by which they do this, are not clear. In order to explore one such protein, we developed a 2H5-F3 monoclonal antibody (2H5-F3 mAb) through its binding to bovine M cells, and identified the antibody reactive molecule as cyclophilin A (Cyp-A). The localization patterns of Cyp-A were very similar to the localization pattern of cytokeratin (CK) 18-positive M cells. Cyp-A was identified at the luminal surface of CK18-positive M cells in bovine jejunal and ileal FAE. The membranous localization of Cyp-A in the bovine intestinal cell line (BIE cells) increased as cells differentiated toward M cells, as determined by flow cytometry analysis. Additionally, BIE cells released Cyp-A to the extracellular space and the differentiation of BIE cells to M cells increased the secretion of Cyp-A, as determined by western blotting. Accordingly, Cyp-A may be localized in M cells in the small intestinal epithelium of cattle. The rise of the membranous localization and secretion of Cyp-A by differentiation toward M cells indicates that Cyp-A has an important role in the function of M cells. While Cyp-A of the M cell membrane may contribute to the uptake of viruses with peptidyl-prolyl cis-trans isomerase activity, in the extracellular space Cyp-A may work as a chemokine and contribute to the distribution of immuno-competent cells. PMID:26899250

  5. Pigment epithelium-derived factor mediates impaired lung vascular development in neonatal hyperoxia.

    PubMed

    Chetty, Anne; Bennett, Michelle; Dang, Linh; Nakamura, Daisy; Cao, Gong-Jie; Mujahid, Sana; Volpe, MaryAnn; Herman, Ira; Becerra, S Patricia; Nielsen, Heber C

    2015-03-01

    Bronchopulmonary dysplasia is a chronic lung disease of preterm infants characterized by arrested microvascularization and alveolarization. Studies show the importance of proangiogenic factors for alveolarization, but the importance of antiangiogenic factors is unknown. We proposed that hyperoxia increases the potent angiostatin, pigment epithelium-derived factor (PEDF), in neonatal lungs, inhibiting alveolarization and microvascularization. Wild-type (WT) and PEDF(-/-) mice were exposed to room air (RA) or 0.9 fraction of inspired oxygen from Postnatal Day 5 to 13. PEDF protein was increased in hyperoxic lungs compared with RA-exposed lungs (P < 0.05). In situ hybridization and immunofluorescence identified PEDF production primarily in alveolar epithelium. Hyperoxia reduced alveolarization in WT mice (P < 0.05) but not in PEDF(-/-) mice. WT hyperoxic mice had fewer platelet endothelial cell adhesion molecule (PECAM)-positive cells per alveolus (1.4 ± 0.4) than RA-exposed mice (4.3 ± 0.3; P < 0.05); this reduction was absent in hyperoxic PEDF(-/-) mice. The interactive regulation of lung microvascularization by vascular endothelial growth factor and PEDF was studied in vitro using MFLM-91U cells, a fetal mouse lung endothelial cell line. Vascular endothelial growth factor stimulation of proliferation, migration, and capillary tube formation was inhibited by PEDF. MFLM-91U cells exposed to conditioned medium (CM) from E17 fetal mouse lung type II (T2) cells cultured in 0.9 fraction of inspired oxygen formed fewer capillary tubes than CM from T2 cells cultured in RA (hyperoxia CM, 51 ± 10% of RA CM, P < 0.05), an effect abolished by PEDF antibody. We conclude that PEDF mediates reduced vasculogenesis and alveolarization in neonatal hyperoxia. Bronchopulmonary dysplasia likely results from an altered balance between pro- and antiangiogenic factors. PMID:25054647

  6. Functional and molecular biological evidence of SGLT-1 in the ruminal epithelium of sheep.

    PubMed

    Aschenbach, J R; Wehning, H; Kurze, M; Schaberg, E; Nieper, H; Burckhardt, G; Gäbel, G

    2000-07-01

    Because of the effective catabolism of D-glucose to short-chain fatty acids by intraruminal microorganisms, the absorption of D-glucose from the rumen was thought to be of minor importance. However, clinical studies suggested that significant quantities of D-glucose are transported from the ruminal contents to the blood. We therefore tested the ruminal epithelium of sheep for the presence of Na(+)-glucose cotransporter 1 (SGLT-1) on both the functional and mRNA levels. In the absence of an electrochemical gradient, 3-O-methylglucose (3-OMG) was net absorbed across isolated ruminal epithelia mounted in Ussing chambers. The net transport of 3-OMG followed Michaelis-Menten kinetics and was sensitive to phlorizin or decreasing Na(+) concentrations. The mucosal addition of 10 mM D-glucose induced an immediate, phlorizin-sensitive increase in short-circuit current (I(sc)). I(sc) could also be increased by serosal addition of D-glucose or D-mannose, but electrogenic uptake of D-glucose or 3-OMG added on the mucosal side was still detectable after serosal stimulation of I(sc). RT-PCR using primers specific for the ovine intestinal SGLT-1 with subsequent TA cloning and sequencing revealed 100% identity between the cloned cDNA and mRNA fragment 187-621 of ovine intestinal SGLT-1. In conclusion, the ruminal epithelium has a high-affinity SGLT-1, which indicates that it maintains the capacity for D-glucose absorption. PMID:10898743

  7. Electrophysiological properties of the tongue epithelium of the toad Bufo marinus.

    PubMed

    Baker, Timothy K; Rios, Karina; Hillyard, Stanley D

    2002-07-01

    The dorsal lingual epithelium from the tongue of the toad Bufo marinus was mounted in an Ussing-type chamber, and the short-circuit current (I(sc)) was measured using a low-noise voltage clamp. With NaCl Ringer bathing the mucosal and serosal surfaces of the isolated tissue, an outwardly directed (mucosa-positive) I(sc) was measured that averaged -10.71+/-0.82 microA cm(-2) (mean +/- S.E.M., N=24) with a resistance of 615+/-152 Omega cm(2) (mean +/- S.E.M., N=10). Substitution of chloride with sulfate as the anion produced no significant change in I(sc). Fluctuation analysis with either NaCl or Na(2)SO(4) Ringer bathing both sides of the tissue revealed a spontaneous Lorentzian component, suggesting that the I(sc) was the result of K(+) secretion through spontaneously fluctuating channels in the apical membrane of the epithelium. This hypothesis was supported by the reversible inhibition of I(sc) by Ba(2+) added to the mucosal Ringer. Analysis of the kinetics of Ba(2+) inhibition of I(sc) indicates that there might be more than one type of K(+) channel carrying the I(sc). This hypothesis was supported by power spectra obtained with a serosa-to-mucosa K(+) gradient, which could be fitted to two Lorentzian components. At present, the K(+) secretory current cannot be localized to taste cells or other cells that might be associated with the secretion of saliva or mucus. Nonetheless, the resulting increase in [K(+)] in fluid bathing the mucosal surface of the tongue could presumably affect the sensitivity of the taste cells. These results contrast with those from the mammalian tongue, in which a mucosa-negative I(sc) results from amiloride-sensitive Na(+) transport. PMID:12077171

  8. A breakdown in communication? Understanding the effects of aging on the human small intestine epithelium

    PubMed Central

    2015-01-01

    In the intestine, a single layer of epithelial cells sealed together at their apical surfaces by tight junctions helps to prevent the luminal commensal and pathogenic micro-organisms and their toxins from entering host tissues. The intestinal epithelium also helps to maintain homoeostasis in the mucosal immune system by expressing anti-inflammatory cytokines in the steady state and inflammatory cytokines in response to pathogens. Although the function of the mucosal immune system is impaired in elderly humans, the molecular mechanisms which cause this dramatic functional decline are poorly understood. Our current understanding of the effects of aging on the physical and immunological properties of the intestinal epithelial barrier is also very limited. In this issue of Clinical Science, Man et al. provide further insight into the effects of aging on small intestinal barrier function in humans and the influence that gut luminal micro-organisms may have on it. Using human terminal ileal biopsy tissues they show that intestinal permeability to solutes, but not macromolecules, was significantly increased in the intestines of elderly humans. This was accompanied by elevated expression of the pro-inflammatory cytokine interleukin (IL)-6 which appeared to modulate claudin-2 expression and solute permeability in the epithelium. Conversely, IL-8 synthesis in response to flagellin stimulation was reduced in intestines of the elderly subjects, but was not associated with effects on Toll-like receptor 5 (TLR5) expression. These data provide an important advance in our understanding on the effects of aging on intestinal permeability and innate mucosal immune responsiveness in elderly humans. PMID:26186738

  9. Inherent tone of human bronchus: role of eicosanoids and the epithelium

    PubMed Central

    Watson, N; Magnussen, H; Rabe, K F

    1997-01-01

    Airway preparations of different species possess varying degrees of inherent tone which is the result of different metabolites of arachidonic acid in different species. In human bronchial smooth muscle in vitro we have investigated the effects of 5-lipoxygenase inhibition (zileuton, 10 μM), cyclo-oxygenase inhibition (indomethacin, 1 μM) and mechanical epithelium removal on inherent tone. The shunting of arachidonic acid by inhibition of one or other of these enzymes, as a possible explanation for the effects observed, has also been investigated. Zileuton caused a significant fall in tone either alone (−107±33 mg) or after cyclo-oxygenase inhibition (−203±48 mg) and this effect was not significantly altered by epithelial removal (−191±43 mg alone; −333±88 mg after indomethacin). Indomethacin increased tone when applied alone (160±94 mg), but this effect only reached statistical significance after 5-lipoxygenase inhibition, (210±81 mg; P<0.05). Epithelial removal did not alter the effect of indomethacin when applied alone (213±97 mg), but significantly reduced the effect of indomethacin after 5-lipoxygenase inhibition (34±23 mg; P<0.05). These data suggest that inherent tone in human bronchus is largely the result of contractile 5-lipoxygenase products. However, the involvement of cyclo-oxygenase products cannot entirely be discounted, since in the presence of 5-lipoxygenase inhibition contractile and relaxant eicosanoids originating from the bronchial epithelium appear to influence significantly inherent tone. PMID:9249244

  10. CFTR gene transfer to lung epithelium--on the trail of a target cell.

    PubMed

    O'Dea, S; Harrison, D J

    2002-05-01

    Cystic fibrosis (CF) is a lethal inherited disease that afflicts up to 1 in 2,500 people in the western world. Since 1989, when mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene were identified as responsible for the disease, intense effort has been applied to the development of replacement gene therapy strategies to cure CF. Problems with basic gene delivery techniques along with limited knowledge of the pathogenesis of CF have hindered progress so far. However, recent insights into the expression patterns and functions of CFTR in developing and adult lungs are now advancing our understanding of this disease. It is becoming apparent that progress in gene delivery to cure CF may be best served by identification of a target cell(s) around which gene transfer strategies can be specifically tailored to most closely reproduce the effects of normal CFTR expression. In fact, accurate restoration of endogenous expression patterns may be crucial, not only for disease reversal, but also to avoid potentially deleterious effects of inappropriate expression. This approach is in turn confounded however, by ill-defined stem and progenitor cell pathways within the lung epithelium. Nonetheless, studies to date suggest that these pathways are relatively plastic and may respond differently during homeostasis compared with repair following injury. It may therefore be feasible to target the lung epithelium in a non-cell specific manner and allow endogenous differentiation pathways to subsequently establish correct CFTR distribution patterns. In this review, emerging information on CFTR expression and function in developing and adult lungs is discussed in the context of putative stem cell populations and their potential for current gene delivery approaches. PMID:12109214

  11. 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. PMID:7325782

  12. Response of rat tracheal epithelium to ozone and oxygen exposure in vitro

    SciTech Connect

    Nikula, K.J.; Wilson, D.W. )

    1990-07-01

    Although ozone-induced epithelial injury in vivo has been morphologically characterized, effects of gaseous oxidants on respiratory epithelium in organ culture, where tissue organization is maintained but systemic influences are eliminated, have not been thoroughly investigated. In this study, we exposed tracheal organ cultures from rats to 95% oxygen and 1 ppm ozone, alone and in combination, to determine (1) whether epithelial responses to ozone similar to those observed in vivo occur in airways separated from systemic physiologic, secretory, and inflammatory reactions; (2) whether concentrations of oxygen sufficient to potentially cause oxidant injury result in morphologic epithelial alterations similar to those that occur in ozone toxicity; and (3) if the combined oxidant insult of oxygen and ozone results in more severe damage to the tracheal epithelium than occurs with ozone in air. Tracheal organ cultures were exposed to filtered air and 5% carbon dioxide; filtered air, 5% carbon dioxide, and 1 ppm ozone; 95% oxygen and 5% carbon dioxide; or 95% oxygen, 5% carbon dioxide, and 1 ppm ozone for 96 hr. Light- and quantitative electron-microscopic evaluation showed that epithelia exposed to 1 ppm ozone in air exhibited loss of ciliated cells and ciliated cell damage. The epithelia exposed to 95% oxygen and 5% carbon dioxide were pseudostratified, columnar, ciliated, and hyperplastic. Epithelia exposed to 95% oxygen plus 1 ppm ozone were stratified and nonciliated or very sparsely ciliated. The predominant cell types in epithelia exposed to oxygen plus ozone were serous cells and metaplastic cells, and focal aggregates of adherent necrotic cells were present. We conclude that there was a synergism between oxygen and ozone exposure leading to enhanced epithelial injury and metaplasia.

  13. MWCNT causes extensive damage to the ciliated epithelium of the trachea of rodents.

    PubMed

    Ohba, Teruya; Xu, Jiegou; Alexander, David B; Yamada, Akane; Kanno, Jun; Hirose, Akihiko; Tsuda, Hiroyuki; Imaizumi, Yuji

    2014-06-01

    The ciliated tracheobronchial epithelium plays an important role in the excretion of inhaled dust. While many reports indicate that inhaled multi-walled carbon nanotubes (MWCNT) induce inflammation and proliferative changes in the lung and pleura, their effects on the upper airway have not been reported. Two different types of MWCNTs, MWCNT-L (8 µm in length and 150 nm in diameter) and MWCNT-S (3 µm in length and 15 nm in diameter), were examined for their effect on the trachea as well as the bronchus and lung. In vitro, the movement of the cilia of primary tracheal epithelial cells was impaired by treatment with the 2 MWCNTs. Rats were treated with 0.3 ml of a 250 µg/ml suspension of MWCNTs on days 1, 4, and 7, and sacrificed on day 8. Extensive loss of ciliated cells and replacement by flat cells without cilia was observed in the trachea. Deposition of MWCNTs and occasional squamous cell metaplasia were found in the regenerative granulation tissue. The proportion of the lesion to the transverse section of the trachea was vehicle, 0; MWCNT-L, 27.2 ± 10.5; MWCNT-S, 32.1 ± 15.8 (both MWCNTs, p < 0.001 vs vehicle). The amount of cilia showed significant decrease in the MWCNT-L treated rats  (p < 0.05). In contrast to the trachea lesions, the number of inflammatory foci in the lung was greater in the MWCNT-S than in the MWCNT-L treated rats. Our results indicate that both MWCNTs caused extensive damage to the ciliated epithelium of the trachea. This damage may prolong the deposition of inhaled MWNCT in the lung. PMID:24849684

  14. Effects of ouabain and furosemide on transepithelial electrical parameters of the isolated shark ciliary epithelium.

    PubMed

    Wiederholt, M; Zadunaisky, J A

    1987-08-01

    Sections of the ciliary epithelium of adult sharks (Squalus acanthias) were mounted in Ussing-type chambers (area 0.2 cm2) for measurements of transepithelial potential difference (PD), short circuit current (SCC) and calculation of transepithelial resistance (R). In 15 preparations PD was aqueous side negative (-0.51 +/- 0.12 mV; SCC 18.3 +/- 2.5 microA cm-2; R 30.7 +/- 3.1 Ohm cm2). However, in 15 other preparations incubated in identical Ringer's solution PD was aqueous side positive (0.53 +/- 0.09 mV; SCC -19.6 +/- 2.3 microA cm-2; R 27.9 +/- 2.8 Ohm cm2). 10(-5) M ouabain or 10(-4) M furosemide were applied either to the aqueous or blood side of the isolated ciliary epithelium at transepithelial negative or positive PD. When the transepithelial PD was positive on the aqueous side ouabain decreased PD and SCC within 15 to 45 min. When the spontaneous PD was negative both PD and SCC decreased when ouabain was applied to the blood side. When the drug was given to the aqueous side a biphasic response (first stimulation, then inhibition) of PD and SCC was observed. Furosemide when given to the blood side (with aqueous side PD positive) or to the aqueous side (with aqueous side PD negative) decreased PD and SCC. However, a transient stimulation of both electrical parameters was observed when furosemide was applied to either the blood side (with aqueous side PD negative) or to the aqueous side (with aqueous side PD positive). The polarity and magnitude of PD and SCC probably depend on the relative activity of sodium and chloride pumps across the cell membranes of the non-pigmented and/or pigmented cell layer. However, additional transport mechanisms cannot be excluded. PMID:3038770

  15. NLRP3 Upregulation in Retinal Pigment Epithelium in Age-Related Macular Degeneration

    PubMed Central

    Wang, Yujuan; Hanus, Jakub W.; Abu-Asab, Mones S.; Shen, Defen; Ogilvy, Alexander; Ou, Jingxing; Chu, Xi K.; Shi, Guangpu; Li, Wei; Wang, Shusheng; Chan, Chi-Chao

    2016-01-01

    Inflammation and oxidative stress are involved in age-related macular degeneration (AMD) and possibly associated with an activation of neuronal apoptosis inhibitor protein/class II transcription activator of the Major Histocompatibility Complex (MHC)/heterokaryon incompatibility/telomerase-associated protein 1, leucine-rich repeat or nucleotide-binding domain, leucine-rich repeat-containing family, and pyrin domain-containing 3 (NLRP3) inflammasome. In the present study, we used a translational approach to address this hypothesis. In patients with AMD, we observed increased mRNA levels of NLRP3, pro-interleukin-1 beta (IL-1β) and pro-IL-18 in AMD lesions of the retinal pigment epithelium (RPE) and photoreceptor. In vitro, a similar increase was evoked by oxidative stress or lipopolysaccharide (LPS) stimulation in the adult retinal pigment epithelium (ARPE-19) cell line, and the increase was reduced in siRNA transfected cells to knockdown NLRP3. Ultrastructural studies of ARPE-19 cells showed a swelling of the cytoplasm, mitochondrial damage, and occurrence of autophagosome-like structures. NLRP3 positive dots were detected within autophagosome-like structures or in the extracellular space. Next, we used a mouse model of AMD, Ccl2/Cx3cr1 double knockout on rd8 background (DKO rd8) to ascertain the in vivo relevance. Ultrastructural studies of the RPE of these mice showed damaged mitochondria, autophagosome-like structures, and cytoplasmic vacuoles, which are reminiscent of the pathology seen in stressed ARPE-19 cells. The data suggest that the NLRP3 inflammasome may contribute in AMD pathogenesis. PMID:26760997

  16. Morphology of non-sensory epithelium during post-natal development of the rabbit vomeronasal organ.

    PubMed

    Elgayar, S A M; Eltony, S A; Othman, M A

    2014-08-01

    The vomeronasal organ (VNO), because of its ability to detect pheromones, has an important role in many social and sexual behaviours in mammals. It also mediates defensive behaviours through detection of protein pheromone homologues. A detailed morphological description of the post-natal development of the 'non-sensory' epithelium (NSE) of the female rabbit is recorded. Histological techniques were used to study the NSE of the VNO in post-natal development of female rabbits. The study focused on the following post-natal ages: newborn, 1 week, 2 weeks and 1 month (five animals each) beside to two adult animals. The rabbit VNO was surrounded externally by bony capsule and internally by cartilaginous capsule. NSE was pseudostratified columnar partially ciliated epithelium without goblet cells. In addition to basal cells, NSE contained ciliated and three types of non-ciliated columnar cells (dark, pale and light). At birth, dark cells may have primary cilia. By 1 month, the cytoplasm became lighter with less free ribosomes. The pale cells had electron-lucent cytoplasm, which contained a few organelles. Mitotic figures were observed in basal and columnar cells, particularly during the first 2 weeks of post-natal development. Light columnar cells were common during the first week. Numerous leucocytes and a few nerve endings were detected intra-epithelial. Scanning electron microscope revealed a gradual increase in height of microvilli of non-ciliated cells. Ciliated cells had cilia and microvilli. Cells were arranged singly, in clumps or in a dense population of cells. The rabbit VNO-NSE had a unique morphological structure. PMID:23931650

  17. In vivo effects of endotoxin on DNA synthesis in rat nasal epithelium

    SciTech Connect

    Harkema, J.R.; Hotchkiss, J.A. )

    1993-12-01

    Airway inflammation in bacterial infections is characterized by the presence of neutrophils and often epithelial injury and repair. Release of endotoxin from bacteria may contribute to these processes. The purpose of this study was to determine the in vivo effects of repeated endotoxin exposure on DNA synthesis in rat nasal epithelium in the presence and absence of neutrophilic influx. Rats were intranasally instilled, once a day for 3 days, with endotoxin or saline (controls). Before the first and third instillations, half of the saline and endotoxin-instilled animals were depleted of circulating blood neutrophils by administering a rabbit anti-rat neutrophil antiserum. Rats were sacrificed 6 or 24 h after the last instillation. Two hours prior to sacrifice, rats were intraperitoneally injected with bromodeoxyuridine (BrdU), an analog of thymidine that is incorporated in the nucleus of cells in the S-phase of the cell cycle. Nasal tissues were processed for light microscopy and immunohistochemical detection of BrdU in nasal epithelial cells. The numbers of nasal epithelial cells, BrdU-labeled epithelial nuclei, and neutrophils per millimeter of basal lamina in the epithelium lining the nasal turbinates in the proximal nasal passages were determined by morphometric analysis. The authors did not observe a neutrophilic influx in the nasal tissues of neutrophil-depleted rats at 6 or 24 h after the last endotoxin instillation; however, the numbers of nasal epithelial cells and the BrdU-labeling index were significantly increased compared to saline-instilled controls. In contrast, non-neutrophil-depleted rats instilled with endotoxin had a marked neutrophilic influx, but no significant differences in the number of nasal epithelial cells at 6 or 24 h, compared to controls. In addition, the BrdU-labeling index in neutrophil-sufficient rats was increased only 6 h after the last instillation, compared to controls.

  18. NLRP3 Upregulation in Retinal Pigment Epithelium in Age-Related Macular Degeneration.

    PubMed

    Wang, Yujuan; Hanus, Jakub W; Abu-Asab, Mones S; Shen, Defen; Ogilvy, Alexander; Ou, Jingxing; Chu, Xi K; Shi, Guangpu; Li, Wei; Wang, Shusheng; Chan, Chi-Chao

    2016-01-01

    Inflammation and oxidative stress are involved in age-related macular degeneration (AMD) and possibly associated with an activation of neuronal apoptosis inhibitor protein/class II transcription activator of the Major Histocompatibility Complex (MHC)/heterokaryon incompatibility/telomerase-associated protein 1, leucine-rich repeat or nucleotide-binding domain, leucine-rich repeat-containing family, and pyrin domain-containing 3 (NLRP3) inflammasome. In the present study, we used a translational approach to address this hypothesis. In patients with AMD, we observed increased mRNA levels of NLRP3, pro-interleukin-1 beta (IL-1β) and pro-IL-18 in AMD lesions of the retinal pigment epithelium (RPE) and photoreceptor. In vitro, a similar increase was evoked by oxidative stress or lipopolysaccharide (LPS) stimulation in the adult retinal pigment epithelium (ARPE-19) cell line, and the increase was reduced in siRNA transfected cells to knockdown NLRP3. Ultrastructural studies of ARPE-19 cells showed a swelling of the cytoplasm, mitochondrial damage, and occurrence of autophagosome-like structures. NLRP3 positive dots were detected within autophagosome-like structures or in the extracellular space. Next, we used a mouse model of AMD, Ccl2/Cx3cr1 double knockout on rd8 background (DKO rd8) to ascertain the in vivo relevance. Ultrastructural studies of the RPE of these mice showed damaged mitochondria, autophagosome-like structures, and cytoplasmic vacuoles, which are reminiscent of the pathology seen in stressed ARPE-19 cells. The data suggest that the NLRP3 inflammasome may contribute in AMD pathogenesis. PMID:26760997

  19. Ionic mechanisms of Ca(2+)-dependent electrolyte transport across equine sweat gland epithelium.

    PubMed Central

    Ko, W H; Chan, H C; Chew, S B; Wong, P Y

    1996-01-01

    1. The ionic mechanism involved in Ca(2+)-stimulated electrolyte transport in cultured equine sweat gland epithelial cells was studied using the short-circuit current (ISC) technique. 2. Microscopy revealed that the cultured cells grown on Millipore filters formed polarized monolayers with tight junctions. Monolayers exhibited a mean transepithelial resistance of 333.9 +/- 40.4 omega cm2. 3. Ca(2+)-mobilizing agents, A23187 (1 microM) or thapsigargin (0.01-1 microM), stimulated ISC while forskolin exerted little effect on the ISC. 4. Replacement of external Cl- by gluconate significantly reduced the ISC by 63% when stimulated by 0.1 microM thapsigargin. Residual ISC could be abolished (> 99%) by elimination of HCO3- from the bathing solution. 5. Basolateral addition of bumetanide (0.1 mM), ouabain (0.01 mM) and acetazolamide (45 microM) and apical addition of methyl isobutyl amiloride (MIA, 1-100 microM) all had inhibitory effects on the thapsigargin-stimulated ISC to various extents. 6. Substantial current inhibition could be obtained using 4, 4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) and diphenylamine-2-carboxylate (DPC) in a concentration-dependent manner. 7. The K+ channel blocker barium (5 mM) was effective on both sides of the epithelium with a much larger effect on the basolateral side. 8. The inhibitory effects of acetazolamide, amiloride, MIA, DIDS and DPC on the thapsigargin-stimulated ISC were also observed when a Cl(-)-free solution was used. 9. The results provide evidence for Ca(2+)-stimulated HCO3- as well as Cl- secretion by equine sweat gland epithelium. Images Figure 1 PMID:8799908

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. [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. PMID:26762038

  5. Immunolocalization of NLRP3 Inflammasome in Normal Murine Airway Epithelium and Changes following Induction of Ovalbumin-Induced Airway Inflammation.

    PubMed

    Tran, Hai B; Lewis, Martin D; Tan, Lor Wai; Lester, Susan E; Baker, Leonie M; Ng, Jia; Hamilton-Bruce, Monica A; Hill, Catherine L; Koblar, Simon A; Rischmueller, Maureen; Ruffin, Richard E; Wormald, Peter J; Zalewski, Peter D; Lang, Carol J

    2012-01-01

    Little is known about innate immunity and components of inflammasomes in airway epithelium. This study evaluated immunohistological evidence for NLRP3 inflammasomes in normal and inflamed murine (Balb/c) airway epithelium in a model of ovalbumin (OVA) induced allergic airway inflammation. The airway epithelium of control mice exhibited strong cytoplasmic staining for total caspase-1, ASC, and NLRP3, whereas the OVA mice exhibited strong staining for active caspase-1, with redistribution of caspase-1, IL-1β and IL-18, indicating possible activation of the NLRP3 inflammasome. Active caspase-1, NLRP3, and other inflammasome components were also detected in tissue eosinophils from OVA mice, and may potentially contribute to IL-1β and IL-18 production. In whole lung, inRNA expression of NAIP and procaspase-1 was increased in OVA mice, whereas NLRP3, IL-1β and IL-18 decreased. Some OVA-treated mice also had significantly elevated and tightly correlated serum levels of IL-1β and TNFα. In cultured normal human bronchial epithelial cells, LPS priming resulted in a significant increase in NLRP3 and II-lp protein expression. This study is the first to demonstrate NLRP3 inflammasome components in normal airway epithelium and changes with inflammation. We propose activation and/or luminal release of the inflammasome is a feature of allergic airway inflammation which may contribute to disease pathogenesis. PMID:22523501

  6. Interactions between bacteria and the gut mucosa: Do enteric neurotransmitters acting on the mucosal epithelium influence intestinal colonization or infection?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The intestinal epithelium is a critical barrier between the internal and external milieux of the mammalian host. Epithelial interactions between these two host environments have been shown to be modulated by several different, cross-communicating cell types residing in the gut mucosa. These include ...

  7. Virus-like particles in the follicular epithelium of the thyroid from a patient with subacute thyroiditis (De Quervain).

    PubMed

    Sato, M

    1975-07-01

    The author experienced a case of subacute thyroiditis (de Quervain) in a 36-year-old female. Electron microscopic examination of the thyroid tissue of the patient revealed virus-like particles (VLP) in the degenerated follicular epithelium Judging from the size, the VLP corresponded to the influenza or mumps virus. PMID:1180050

  8. Bidirectional Signaling of Mammary Epithelium and Stroma: Implications for Breast Cancer—Preventive Actions of Dietary Factors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mammary gland is composed of two major cellular compartments: a highly dynamic epithelium that undergoes cycles of proliferation, differentiation, and apoptosis in response to local and endocrine signals and the underlying stroma comprised of fibroblasts, endothelial cells, and adipocytes that c...

  9. Impact of Lactic Acid Bacteria on Dendritic Cells from Allergic Patients in an Experimental Model of Intestinal Epithelium

    PubMed Central

    Ratajczak, Céline; Duez, Catherine; Grangette, Corinne; Pochard, Pierre; Tonnel, André-Bernard; Pestel, Joël

    2007-01-01

    Lactic acid bacteria (LAB) are Gram positive nonpathogenic commensal organisms present in human gastrointestinal tract. In vivo, LAB are separated from antigen-presenting cells such as dendritic cells (DC) by the intestinal epithelial barrier. In this study, the impact of one LAB strain (Lactobacillus casei ATCC393) on human monocyte-derived DC from allergic and healthy donors was assessed by using a polarized epithelium model. Confocal and flow cytometer analyses showed that immature DC efficiently captured FITC-labelled L. casei through the epithelial layer. After interaction with L. casei, DC acquired a partial maturation status (i.e., CD86 and CD54 increase) and increased their interleukin (IL)-10 and IL-12 production. Interestingly, after activation by L. casei in the presence of experimental epithelium, DC from allergic patients instructed autologous naïve CD4+ T cells to produce more interferon-γ than without the epithelium. Thus by modulating human DC reactivity, LAB and intestinal epithelium might modify T cell immune response and regulate the development of allergic reaction. PMID:17497025

  10. CONSTITUTIVE AND STIMULATED MCP-1, GROA, B, AND Y EXPRESSION IN HUMAN A AIRWAY EPITHELIUM AND BRONCHOALVEOLAR MACROPHAGES

    EPA Science Inventory

    Constitutive expression of mRNAs for GROa, GROB, GROY, and MCP-1, belonging to the chemokine family of 8-10 kD cytokines with chemotactic properties for granulocytes and monocytes, has been identified in freshly isolated human nasal and bronchial epithelium, and in bronchoalveola...

  11. Interactions between bacteria and the gut mucosa: Do enteric neurotransmitters acting on the mucosal epithelium influence intestinal colonization or infection?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The intestinal epithelium is a critical barrier between the internal and external milieux of the mammalian host. Epithelial interactions between these two host environments have been shown to be modulated by several different, cross-communicating cell types residing in the gut mucosa. These includ...

  12. Near infrared (NIr) light increases expression of a marker of mitochondrial function in the mouse vestibular sensory epithelium.

    PubMed

    Zhang, Lucy; Tung, Victoria W K; Mathews, Miranda; Camp, Aaron J

    2015-01-01

    Strategies for attenuating decline in balance function with increasing age are predominantly focused on physical therapies including balance tasks and exercise. However, these approaches do not address the underlying causes of balance decline. Using mice, the impact of near infrared light (NIr) on the metabolism of cells in the vestibular sensory epithelium was assessed. Data collected shows that this simple and safe intervention may protect these vulnerable cells from the deleterious effects of natural aging. mRNA was extracted from the isolated peripheral vestibular sensory epithelium (crista ampullaris and utricular macula) and subsequently transcribed into a cDNA library. This library was then probed for the expression of ubiquitous antioxidant (SOD-1). Antioxidant gene expression was then used to quantify cellular metabolism. Using transcranial delivery of NIr in young (4 weeks) and older (8-9 months) mice, and a brief treatment regime (90 sec/day for 5 days), this work suggests NIr alone may be sufficient to improve mitochondrial function in the vestibular sensory epithelium. Since there are currently no available, affordable, non-invasive methods of therapy to improve vestibular hair cell function, the application of external NIr radiation provides a potential strategy to counteract the impact of aging on cellular metabolism inthe vestibular sensory epithelium. PMID:25868009

  13. Collagen-immobilized poly(vinyl alcohol) as an artificial cornea scaffold that supports a stratified corneal epithelium.

    PubMed

    Miyashita, Hideyuki; Shimmura, Shigeto; Kobayashi, Hisatoshi; Taguchi, Tetsushi; Asano-Kato, Naoko; Uchino, Yuichi; Kato, Masabumi; Shimazaki, Jun; Tanaka, Junzo; Tsubota, Kazuo

    2006-01-01

    The cornea is a transparent tissue of the eye, which is responsible for the refraction of incoming light. Both biological corneal equivalents and synthetic keratoprostheses have been developed to replace donor tissue as a means to restore vision. However, both designs have drawbacks in terms of stability and biocompatibility. Clinically available synthetic devices do not support an intact epithelium, which poses a risk of microbial infection or protrusion of the prosthesis. In the present study, type I collagen was immobilized onto poly(vinyl alcohol) (PVA-COL) as a possible artificial cornea scaffold that can sustain a functional corneal epithelium. Human and rabbit corneal epithelial cells were air-lift cultured with 3T3 feeder fibroblasts to form a stratified epithelial layer on PVA-COL. The epithelial sheet expressed keratin 3/12 differentiation markers, the tight junction protein occludin, and had characteristic microvilli structures on transmission electron microscopy. Functionally, the stratified epithelium contained normal glycogen levels, and an apical tight-junction network was observed to exclude the diffusion of horseradish peroxidase. Furthermore, the epithelium-PVA-COL composite was suturable in the rabbit cornea, suggesting the possibility of using PVA-COL as a biocompatible material for keratoprosthesis. PMID:16044431

  14. Dedicated immunosensing of the mouse intestinal epithelium facilitated by a pair of genetically coupled lectin-like receptors.

    PubMed

    Leibelt, S; Friede, M E; Rohe, C; Gütle, D; Rutkowski, E; Weigert, A; Kveberg, L; Vaage, J T; Hornef, M W; Steinle, A

    2015-03-01

    The integrity of the intestinal epithelium is constantly surveyed by a peculiar subset of innate-like T lymphocytes embedded in the epithelial cell layer, hence called intestinal intraepithelial lymphocytes (IELs). IELs are thought to act as "first-line" sentinels sensing the state of adjacent epithelial cells via both T-cell receptors and auxiliary receptors. Auxiliary receptors modulating IEL activity include C-type lectin-like receptors encoded in the natural killer gene complex such as NKG2D. Here, we report that the CTLR Nkrp1g is expressed by a subpopulation of mouse CD103(+) IELs allowing immunosensing of the intestinal epithelium through ligation of the genetically coupled CTLR Clr-f that is almost exclusively expressed on differentiated intestinal epithelial cells (IECs). Most of these Nkrp1g-expressing IELs exhibit a γδTCR(bright)Nkg2a(-) phenotype and are intimately associated with the intestinal epithelium. As Clr-f expression strongly inhibits effector functions of Nkrp1g-expressing cells and is upregulated upon poly(I:C) challenge, Clr-f molecules may quench reactivity of these IELs towards the epithelial barrier that is constantly provoked by microbial and antigenic stimuli. Altogether, we here newly characterize a genetically linked C-type lectin-like receptor/ligand pair with a highly restricted tissue expression that apparently evolved to allow for a dedicated immunosurveillance of the mouse intestinal epithelium. PMID:24985083

  15. Dicer1 Ablation in the Mouse Epididymis Causes Dedifferentiation of the Epithelium and Imbalance in Sex Steroid Signaling

    PubMed Central

    Björkgren, Ida; Saastamoinen, Lauri; Krutskikh, Anton; Huhtaniemi, Ilpo; Poutanen, Matti; Sipilä, Petra

    2012-01-01

    Background The postnatal development of the epididymis is a complex process that results in a highly differentiated epithelium, divided into several segments. Recent studies indicate a role for RNA interference (RNAi) in the development of the epididymis, however, the actual requirement for RNAi has remained elusive. Here, we present the first evidence of a direct need for RNAi in the differentiation of the epididymal epithelium. Methodology/Principal Findings By utilizing the Cre-LoxP system we have generated a conditional knock-out of Dicer1 in the two most proximal segments of the mouse epididymis. Recombination of Dicer1, catalyzed by Defb41iCre/wt, took place before puberty, starting from 12 days postpartum. Shortly thereafter, downregulation of the expression of two genes specific for the most proximal epididymis (lipocalin 8 and cystatin 8) was observed. Following this, segment development continued until week 5 at which age the epithelium started to regress back to an undifferentiated state. The dedifferentiated epithelium also showed an increase in estrogen receptor 1 expression while the expression of androgen receptor and its target genes; glutathione peroxidase 5, lipocalin 5 and cysteine-rich secretory protein 1 was downregulated, indicating imbalanced sex steroid signaling. Conclusions/Significance At the time of the final epididymal development, Dicer1 acts as a regulator of signaling pathways essential for maintaining epithelial cell differentiation. PMID:22701646

  16. 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...

  17. 77 FR 73054 - Petition for Modification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Mine Safety and Health Administration Petition for Modification AGENCY: Mine Safety and Health Administration, Labor. ACTION: Notice; correction. SUMMARY: This notice amends a petition for modification published...

  18. 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.

  19. Implementing a QA program for plant modifications

    SciTech Connect

    Palmer, D.R.

    1985-11-01

    The purpose of this paper is to describe the implementation of the quality assurance (QA) program within the modification process at Niagara Mohawk Power Corporation. The modification process includes design, procurement, installation, transition to operations, and closeout. Niagara Mohawk Power Corporation operates one nuclear power plant, a 610-MW General Electric (GE) boiling water reactor, and has another under construction, a 1080-MW GE reactor planned for commercial operation in October 1986. Niagara Mohawk has achieved a marked improvement in the implementation of its nuclear modifications. Modifications are now generally completed within budget and either on schedule or ahead of schedule. An example (the recirculation pipe replacement modification) is discussed and illustrates the increased QA attention to major modifications. This modification was a success from both Niagara Mohawk's point of view and also from our contractor's point of view. The implementation of the quality plan was a positive factor in the success of this modification.

  20. A model for shape generation by strain and cell-cell adhesion in the epithelium of an arthropod leg segment.

    PubMed

    Mittenthal, J E; Mazo, R M

    1983-02-01

    We present a model for the energetic factors determining the most stable shape of a tubular epithelium such as the hypodermis of an arthropod leg segment. The model uses the analysis by Steinberg (1963) of rearrangement of cells in aggregates under the influence of differential adhesion, combining this analysis with the assumption that the epithelium behaves as an elastic sheet. The epithelium is assumed to consist of blocks of cells with different adhesive affinities, which remain unmixed in a quilt pattern. Rearrangement of cells within each block can adjust the shape of the tube by changing the shapes of the blocks. By means of such rearrangements the tube develops that shape which minimizes a free energy. The free energy is the difference between the energy of mechanical strain due to bending of the epithelium and the work of adhesion among cells. Minimization of the free energy for a cylindrical segment yields a scaling relation involving the length and radius of the segment. Leg segments of Drosophila conformed approximately to this relation, with deviations which suggest that a whole-limb pattern of adhesive affinities modulates the shaping effects of an adhesive pattern repeated in each leg segment. The model also predicts a transient deformation in an epithelium following a grafting operation. For example, deleting a slab of tissue from a tubular segment and reuniting the cut ends should produce a constriction of the tube at the host-graft junction. We propose that patterns of strain and adhesion can provide positional information which regulates subsequent development. Local increases in strain or adhesive disparity may stimulate mitoses; the resulting changes in distribution of cells will affect morphogenesis. PMID:6834865