Dysregulation of mitotic machinery genes precedes genome instability during spontaneous pre-malignant transformation of mouse ovarian surface epithelial cells.

PubMed

Urzúa, Ulises; Ampuero, Sandra; Roby, Katherine F; Owens, Garrison A; Munroe, David J

2016-10-25

Based in epidemiological evidence, repetitive ovulation has been proposed to play a role in the origin of ovarian cancer by inducing an aberrant wound rupture-repair process of the ovarian surface epithelium (OSE). Accordingly, long term cultures of isolated OSE cells undergo in vitro spontaneous transformation thus developing tumorigenic capacity upon extensive subcultivation. In this work, C57BL/6 mouse OSE (MOSE) cells were cultured up to passage 28 and their RNA and DNA copy number profiles obtained at passages 2, 5, 7, 10, 14, 18, 23, 25 and 28 by means of DNA microarrays. Gene ontology, pathway and network analyses were focused in passages earlier than 20, which is a hallmark of malignancy in this model. At passage 14, 101 genes were up-regulated in absence of significant DNA copy number changes. Among these, the top-3 enriched functions (>30 fold, adj p < 0.05) comprised 7 genes coding for centralspindlin, chromosome passenger and minichromosome maintenance protein complexes. The genes Ccnb1 (Cyclin B1), Birc5 (Survivin), Nusap1 and Kif23 were the most recurrent in over a dozen GO terms related to the mitotic process. On the other hand, Pten plus the large non-coding RNAs Malat1 and Neat1 were among the 80 down-regulated genes with mRNA processing, nuclear bodies, ER-stress response and tumor suppression as relevant terms. Interestingly, the earliest discrete segmental aneuploidies arose by passage 18 in chromosomes 7, 10, 11, 13, 15, 17 and 19. By passage 23, when MOSE cells express the malignant phenotype, the dysregulated gene expression repertoire expanded, DNA imbalances enlarged in size and covered additional loci. Prior to early aneuploidies, overexpression of genes coding for the mitotic apparatus in passage-14 pre-malignant MOSE cells indicate an increased proliferation rate suggestive of replicative stress. Concomitant down-regulation of nuclear bodies and RNA processing related genes suggests altered control of nuclear RNA maturation, features recently linked to impaired DNA damage response leading to genome instability. These results, combined with cytogenetic analysis by other authors in this model, suggest that transcriptional profile at passage 14 might induce cytokinesis failure by which tetraploid cells approach a near-tetraploid stage containing primary chromosome aberrations that initiate the tumorigenic drive.

Surface Monitoring of CFRP Structures for Adhesive Bonding

NASA Technical Reports Server (NTRS)

Ledesma, Rodolfo; Palmieri, Frank L.; Yost, William T.; Connell, John W.; Fitz-Gerald, James M.

2017-01-01

Adhesive bonding of composite materials requires reliable monitoring and detection of surface contaminants to assure robust and durable bonded structures. Surface treatment and effective monitoring prior to bonding is essential in order to obtain a surface free from contaminants that may degrade structural performance. Two techniques which monitor the effectiveness of the laser surface treatment of carbon fiber reinforced polymer (CFRP) materials are being investigated: laser induced breakdown spectroscopy (LIBS) and optically stimulated electron emission (OSEE). The applicability of LIBS to detect silicone contaminants on CFRP composites is studied using 35 ns Nd:YAG laser pulses at 355 nm with a pulse energy of 45 mJ. The LIBS regime in which pulse energies are < 100 mJ is referred to as mLIBS. CFRP surfaces were contaminated with polydimethylsiloxane (PDMS), a major component of silicone based mold release agents. The presence of PDMS is found by inspecting the Si I emission line at 288.2 nm. Untreated CFRP samples and CFRP contaminated with PDMS were tested. The PDMS areal density ranged from 0.36 Â+/- 0.04 to 0.51 Â+/- 0.16 mg/cm2. The results demonstrate the successful detection of PDMS on CFRP using mLIBS. In addition, OSEE was used to measure CFRP surface cleanliness pre- and post-treatment by laser ablation on specimens contaminated with PDMS coatings from 8 nm to 1311 nm in thickness. The results showed a significant increase in the OSEE photocurrent after laser surface treatment.

Substance P acts via the neurokinin receptor 1 to elicit bronchoconstriction, oxidative stress, and upregulated ICAM-1 expression after oil smoke exposure.

PubMed

Li, Ping-Chia; Chen, Wen-Chung; Chang, Li-Ching; Lin, Shao-Chieh

2008-05-01

This study aimed to 1) assess whether substance P (SP) acts via neurokinin (NK)-1 and NK-2 receptors to stimulate neurogenic inflammation (indicated by formation of ICAM-1 expression and oxidative stress) following oil smoke exposure (OSE) in rats; and 2) determine if pretreatment with antioxidants ameliorates the deleterious effects of OSE. Rats were pretreated with NK-1 receptor antagonist CP-96345, NK-2 receptor antagonist SR-48968, vitamin C, or catechins. OSE was for 30-120 min. Rats were killed 0-8 h later. Total lung resistance (RL), airway smooth muscle activity (ASMA), lung ICAM-1 expression, neurogenic plasma extravasation (via India ink and Evans blue dye), bronchoalveolar lavage fluid SP concentrations, and reactive oxygen species formation [via lucigenin- and luminal-amplified chemiluminescence (CL)] were assessed. Lung histology was performed. SP concentrations increased significantly in nonpretreated rats following OSE in a dose-dependent manner. RL and total ASMA increased over time after OSE. Vitamin C and catechin pretreatments were associated with significantly reduced lucigenin CL 2 and 4 h after OSE. Pretreatment with catechins significantly reduced luminal CL counts 4 and 8 h after OSE. Evans blue levels were significantly reduced following 60 and 120 min of OSE in catechin- and CP-96345-pretreated rats. ICAM-1 protein expression was significantly decreased in all pretreatment groups after OSE. Thickening of the alveolar capillary membrane, focal hemorrhaging, interstitial pneumonitis, and peribronchiolar inflammation were apparent in OSE lungs. These findings suggest that SP acts via the NK-1 receptor to provoke neurogenic inflammation, oxidative stress, and ICAM-1 expression after OSE in rats.

Differential expression of the P2X7 receptor in ovarian surface epithelium during the oestrous cycle in the mouse.

PubMed

Vázquez-Cuevas, F G; Cruz-Rico, A; Garay, E; García-Carrancá, A; Pérez-Montiel, D; Juárez, B; Arellano, R O

2013-01-01

Purinergic signalling has been proposed as an intraovarian regulatory mechanism. Of the receptors responsible for purinergic transmission, the P2X7 receptor is an ATP-gated cationic channel that displays a broad spectrum of cellular functions ranging from apoptosis to cell proliferation and tumourigenesis. In the present study, we investigated the functional expression of P2X7 receptors in ovarian surface epithelium (OSE). P2X7 protein was detected in the OSE layer of the mouse, both in situ and in primary cultures. In cultures, 2'(3')-O-(4-Benzoylbenzoyl)adenosine-5'-triphosphate (BzATP) activation of P2X7 receptors increased [Ca(2+)]i and induced apoptosis. The functionality of the P2X7 receptor was investigated in situ by intrabursal injection of BzATP on each day of the oestrous cycle and evaluation of apoptosis 24h using the terminal deoxyribonucleotidyl transferase-mediated dUTP-fluorescein nick end-labelling (TUNEL) assay. Maximum effects of BzATP were observed during pro-oestrus, with the effects being blocked by A438079, a specific P2X7 receptor antagonist. Immunofluorescence staining for P2X7 protein revealed more robust expression during pro-oestrus and in OSE regions behind the antral follicles, strongly supporting the notion that the differences in apoptosis can be explained by increased receptor expression, which is regulated during the oestrous cycle. Finally, P2X7 receptor expression was detected in the OSE layer of human ovaries, with receptor expression maintained in human ovaries diagnosed with cancer, as well as in the human ovarian carcinoma SKOV3 cell line.

Multidomain Skyrmion Lattice State in Cu2OSeO3.

PubMed

Zhang, S L; Bauer, A; Burn, D M; Milde, P; Neuber, E; Eng, L M; Berger, H; Pfleiderer, C; van der Laan, G; Hesjedal, T

2016-05-11

Magnetic skyrmions in chiral magnets are nanoscale, topologically protected magnetization swirls that are promising candidates for spintronics memory carriers. Therefore, observing and manipulating the skyrmion state on the surface level of the materials are of great importance for future applications. Here, we report a controlled way of creating a multidomain skyrmion state near the surface of a Cu2OSeO3 single crystal, observed by soft resonant elastic X-ray scattering. This technique is an ideal tool to probe the magnetic order at the L3 edge of 3d metal compounds giving an average depth sensitivity of ∼50 nm. The single-domain 6-fold-symmetric skyrmion lattice can be broken up into domains, overcoming the propagation directions imposed by the cubic anisotropy by applying the magnetic field in directions deviating from the major cubic axes. Our findings open the door to a new way to manipulate and engineer the skyrmion state locally on the surface or on the level of individual skyrmions, which will enable applications in the future.

Common Genetic Variation in Circadian Rhythm Genes and Risk of Epithelial Ovarian Cancer (EOC)

PubMed Central

Jim, Heather S.L.; Lin, Hui-Yi; Tyrer, Jonathan P.; Lawrenson, Kate; Dennis, Joe; Chornokur, Ganna; Chen, Zhihua; Chen, Ann Y.; Permuth-Wey, Jennifer; Aben, Katja KH.; Anton-Culver, Hoda; Antonenkova, Natalia; Bruinsma, Fiona; Bandera, Elisa V.; Bean, Yukie T.; Beckmann, Matthias W.; Bisogna, Maria; Bjorge, Line; Bogdanova, Natalia; Brinton, Louise A.; Brooks-Wilson, Angela; Bunker, Clareann H.; Butzow, Ralf; Campbell, Ian G.; Carty, Karen; Chang-Claude, Jenny; Cook, Linda S.; Cramer, Daniel W.; Cunningham, Julie M.; Cybulski, Cezary; Dansonka-Mieszkowska, Agnieszka; du Bois, Andreas; Despierre, Evelyn; Sieh, Weiva; Doherty, Jennifer A.; Dörk, Thilo; Dürst, Matthias; Easton, Douglas F.; Eccles, Diana M.; Edwards, Robert P.; Ekici, Arif B.; Fasching, Peter A.; Fridley, Brooke L.; Gao, Yu-Tang; Gentry-Maharaj, Aleksandra; Giles, Graham G.; Glasspool, Rosalind; Goodman, Marc T.; Gronwald, Jacek; Harter, Philipp; Hasmad, Hanis N.; Hein, Alexander; Heitz, Florian; Hildebrandt, Michelle A.T.; Hillemanns, Peter; Hogdall, Claus K.; Hogdall, Estrid; Hosono, Satoyo; Iversen, Edwin S.; Jakubowska, Anna; Jensen, Allan; Ji, Bu-Tian; Karlan, Beth Y.; Kellar, Melissa; Kiemeney, Lambertus A.; Krakstad, Camilla; Kjaer, Susanne K.; Kupryjanczyk, Jolanta; Vierkant, Robert A.; Lambrechts, Diether; Lambrechts, Sandrina; Le, Nhu D.; Lee, Alice W.; Lele, Shashi; Leminen, Arto; Lester, Jenny; Levine, Douglas A.; Liang, Dong; Lim, Boon Kiong; Lissowska, Jolanta; Lu, Karen; Lubinski, Jan; Lundvall, Lene; Massuger, Leon F.A.G.; Matsuo, Keitaro; McGuire, Valerie; McLaughlin, John R.; McNeish, Ian; Menon, Usha; Milne, Roger L.; Modugno, Francesmary; Thomsen, Lotte; Moysich, Kirsten B.; Ness, Roberta B.; Nevanlinna, Heli; Eilber, Ursula; Odunsi, Kunle; Olson, Sara H.; Orlow, Irene; Orsulic, Sandra; Palmieri Weber, Rachel; Paul, James; Pearce, Celeste L.; Pejovic, Tanja; Pelttari, Liisa M.; Pike, Malcolm C.; Poole, Elizabeth M.; Schernhammer, Eva; Risch, Harvey A.; Rosen, Barry; Rossing, Mary Anne; Rothstein, Joseph H.; Rudolph, Anja; Runnebaum, Ingo B.; Rzepecka, Iwona K.; Salvesen, Helga B.; Schwaab, Ira; Shu, Xiao-Ou; Shvetsov, Yurii B.; Siddiqui, Nadeem; Song, Honglin; Southey, Melissa C.; Spiewankiewicz, Beata; Sucheston-Campbell, Lara; Teo, Soo-Hwang; Terry, Kathryn L.; Thompson, Pamela J.; Tangen, Ingvild L.; Tworoger, Shelley S.; van Altena, Anne M.; Vergote, Ignace; Walsh, Christine S.; Wang-Gohrke, Shan; Wentzensen, Nicolas; Whittemore, Alice S.; Wicklund, Kristine G.; Wilkens, Lynne R.; Wu, Anna H.; Wu, Xifeng; Woo, Yin-Ling; Yang, Hannah; Zheng, Wei; Ziogas, Argyrios; Amankwah, Ernest; Berchuck, Andrew; Schildkraut, Joellen M.; Kelemen, Linda E.; Ramus, Susan J.; Monteiro, Alvaro N.A.; Goode, Ellen L.; Narod, Steven A.; Gayther, Simon A.; Pharoah, Paul D. P.; Sellers, Thomas A.; Phelan, Catherine M.

2016-01-01

Disruption in circadian gene expression, whether due to genetic variation or environmental factors (e.g., light at night, shiftwork), is associated with increased incidence of breast, prostate, gastrointestinal and hematologic cancers and gliomas. Circadian genes are highly expressed in the ovaries where they regulate ovulation; circadian disruption is associated with several ovarian cancer risk factors (e.g., endometriosis). However, no studies have examined variation in germline circadian genes as predictors of ovarian cancer risk and invasiveness. The goal of the current study was to examine single nucleotide polymorphisms (SNPs) in circadian genes BMAL1, CRY2, CSNK1E, NPAS2, PER3, REV1 and TIMELESS and downstream transcription factors KLF10 and SENP3 as predictors of risk of epithelial ovarian cancer (EOC) and histopathologic subtypes. The study included a test set of 3,761 EOC cases and 2,722 controls and a validation set of 44,308 samples including 18,174 (10,316 serous) cases and 26,134 controls from 43 studies participating in the Ovarian Cancer Association Consortium (OCAC). Analysis of genotype data from 36 genotyped SNPs and 4600 imputed SNPs indicated that the most significant association was rs117104877 in BMAL1 (OR = 0.79, 95% CI = 0.68–0.90, p = 5.59 × 10−4]. Functional analysis revealed a significant down regulation of BMAL1 expression following cMYC overexpression and increasing transformation in ovarian surface epithelial (OSE) cells as well as alternative splicing of BMAL1 exons in ovarian and granulosa cells. These results suggest that variation in circadian genes, and specifically BMAL1, may be associated with risk of ovarian cancer, likely through disruption of hormonal pathways. PMID:26807442

Common Genetic Variation in Circadian Rhythm Genes and Risk of Epithelial Ovarian Cancer (EOC).

PubMed

Jim, Heather S L; Lin, Hui-Yi; Tyrer, Jonathan P; Lawrenson, Kate; Dennis, Joe; Chornokur, Ganna; Chen, Zhihua; Chen, Ann Y; Permuth-Wey, Jennifer; Aben, Katja Kh; Anton-Culver, Hoda; Antonenkova, Natalia; Bruinsma, Fiona; Bandera, Elisa V; Bean, Yukie T; Beckmann, Matthias W; Bisogna, Maria; Bjorge, Line; Bogdanova, Natalia; Brinton, Louise A; Brooks-Wilson, Angela; Bunker, Clareann H; Butzow, Ralf; Campbell, Ian G; Carty, Karen; Chang-Claude, Jenny; Cook, Linda S; Cramer, Daniel W; Cunningham, Julie M; Cybulski, Cezary; Dansonka-Mieszkowska, Agnieszka; du Bois, Andreas; Despierre, Evelyn; Sieh, Weiva; Doherty, Jennifer A; Dörk, Thilo; Dürst, Matthias; Easton, Douglas F; Eccles, Diana M; Edwards, Robert P; Ekici, Arif B; Fasching, Peter A; Fridley, Brooke L; Gao, Yu-Tang; Gentry-Maharaj, Aleksandra; Giles, Graham G; Glasspool, Rosalind; Goodman, Marc T; Gronwald, Jacek; Harter, Philipp; Hasmad, Hanis N; Hein, Alexander; Heitz, Florian; Hildebrandt, Michelle A T; Hillemanns, Peter; Hogdall, Claus K; Hogdall, Estrid; Hosono, Satoyo; Iversen, Edwin S; Jakubowska, Anna; Jensen, Allan; Ji, Bu-Tian; Karlan, Beth Y; Kellar, Melissa; Kiemeney, Lambertus A; Krakstad, Camilla; Kjaer, Susanne K; Kupryjanczyk, Jolanta; Vierkant, Robert A; Lambrechts, Diether; Lambrechts, Sandrina; Le, Nhu D; Lee, Alice W; Lele, Shashi; Leminen, Arto; Lester, Jenny; Levine, Douglas A; Liang, Dong; Lim, Boon Kiong; Lissowska, Jolanta; Lu, Karen; Lubinski, Jan; Lundvall, Lene; Massuger, Leon F A G; Matsuo, Keitaro; McGuire, Valerie; McLaughlin, John R; McNeish, Ian; Menon, Usha; Milne, Roger L; Modugno, Francesmary; Thomsen, Lotte; Moysich, Kirsten B; Ness, Roberta B; Nevanlinna, Heli; Eilber, Ursula; Odunsi, Kunle; Olson, Sara H; Orlow, Irene; Orsulic, Sandra; Palmieri Weber, Rachel; Paul, James; Pearce, Celeste L; Pejovic, Tanja; Pelttari, Liisa M; Pike, Malcolm C; Poole, Elizabeth M; Schernhammer, Eva; Risch, Harvey A; Rosen, Barry; Rossing, Mary Anne; Rothstein, Joseph H; Rudolph, Anja; Runnebaum, Ingo B; Rzepecka, Iwona K; Salvesen, Helga B; Schwaab, Ira; Shu, Xiao-Ou; Shvetsov, Yurii B; Siddiqui, Nadeem; Song, Honglin; Southey, Melissa C; Spiewankiewicz, Beata; Sucheston-Campbell, Lara; Teo, Soo-Hwang; Terry, Kathryn L; Thompson, Pamela J; Tangen, Ingvild L; Tworoger, Shelley S; van Altena, Anne M; Vergote, Ignace; Walsh, Christine S; Wang-Gohrke, Shan; Wentzensen, Nicolas; Whittemore, Alice S; Wicklund, Kristine G; Wilkens, Lynne R; Wu, Anna H; Wu, Xifeng; Woo, Yin-Ling; Yang, Hannah; Zheng, Wei; Ziogas, Argyrios; Amankwah, Ernest; Berchuck, Andrew; Schildkraut, Joellen M; Kelemen, Linda E; Ramus, Susan J; Monteiro, Alvaro N A; Goode, Ellen L; Narod, Steven A; Gayther, Simon A; Pharoah, Paul D P; Sellers, Thomas A; Phelan, Catherine M

Disruption in circadian gene expression, whether due to genetic variation or environmental factors (e.g., light at night, shiftwork), is associated with increased incidence of breast, prostate, gastrointestinal and hematologic cancers and gliomas. Circadian genes are highly expressed in the ovaries where they regulate ovulation; circadian disruption is associated with several ovarian cancer risk factors (e.g., endometriosis). However, no studies have examined variation in germline circadian genes as predictors of ovarian cancer risk and invasiveness. The goal of the current study was to examine single nucleotide polymorphisms (SNPs) in circadian genes BMAL1, CRY2, CSNK1E, NPAS2, PER3, REV1 and TIMELESS and downstream transcription factors KLF10 and SENP3 as predictors of risk of epithelial ovarian cancer (EOC) and histopathologic subtypes. The study included a test set of 3,761 EOC cases and 2,722 controls and a validation set of 44,308 samples including 18,174 (10,316 serous) cases and 26,134 controls from 43 studies participating in the Ovarian Cancer Association Consortium (OCAC). Analysis of genotype data from 36 genotyped SNPs and 4600 imputed SNPs indicated that the most significant association was rs117104877 in BMAL1 (OR = 0.79, 95% CI = 0.68-0.90, p = 5.59 × 10 -4 ]. Functional analysis revealed a significant down regulation of BMAL1 expression following cMYC overexpression and increasing transformation in ovarian surface epithelial (OSE) cells as well as alternative splicing of BMAL1 exons in ovarian and granulosa cells. These results suggest that variation in circadian genes, and specifically BMAL1 , may be associated with risk of ovarian cancer, likely through disruption of hormonal pathways.

OSeMOSYS Energy Modeling Using an Extended UTOPIA Model

ERIC Educational Resources Information Center

Lavigne, Denis

2017-01-01

The OSeMOSYS project offers open-access energy modeling to a wide audience. Its relative simplicity makes it appealing for academic research and governmental organizations to study the impacts of policy decisions on an energy system in the context of possibly severe greenhouse gases emissions limitations. OSeMOSYS is a tool that enhances the…

Dietary supplementation of selenium in inorganic and organic forms differentially and commonly alters blood and liver selenium concentrations and liver gene expression profiles of growing beef heifers.

PubMed

Liao, Shengfa F; Brown, Kelly R; Stromberg, Arnold J; Burris, Walter R; Boling, James A; Matthews, James C

2011-05-01

In geographic regions where selenium (Se) soil concentrations are naturally low, the addition of Se to animal feed is necessary. Even though it is known that Se in grass and forage crops is primarily present in organic forms (especially as L-selenomethionine, L-selenocystine, and L-selenocystathionine), the feeding of Se in the naturally occurring organic selenium (OSe) compounds produces higher blood and tissue Se levels than the inorganic Se (ISe) salts, and that animal metabolism of OSe and ISe is fundamentally different. Se is commonly added in inorganic form as sodium selenite to cattle feeds because it is a less expensive source of supplemental Se then are OSe forms. A trial was conducted with growing cattle to determine if the addition of OSe versus ISe forms of Se in beef cattle feed produces differences in hepatic gene expression, thereby gaining insight into the metabolic consequence of feeding OSe versus ISe. Thirty maturing Angus heifers (261 ± 6 days) were fed a corn silage-based diet with no Se supplementation for 75 days. Heifers (body weight = 393 ± 9 kg) then were randomly assigned (n = 10) and fed Se supplements that contained none (control) or 3 mg Se/day in ISe (sodium selenite) or OSe (Sel-Plex®) form and enough of a common cracked corn/cottonseed hull-based diet (0.48 mg Se/day) to support 0.5 kg/day growth for 105 or 106 days. More Se was found in jugular whole blood and red blood cells and biopsied liver tissue of ISe and OSe treatment animals than control animals, and OSe animals contained more Se in these tissues than did ISe. Microarray and bioinformatic analyses of liver tissue gene expression revealed that the content of at least 80 mRNA were affected by ISe or OSe treatments, including mRNA associated with nutrient metabolism; cellular growth, proliferation, and immune response; cell communication or signaling; and tissue/organ development and function. Overall, three Se supplement-dependent gene groups were identified: ISe-dependent, OSe-dependent, and Se form-independent. More specifically, both forms of supplementation appeared to upregulate mitochondrial gene expression capacity, whereas gene expression of a protein involved in antiviral capacity was downregulated in ISe-supplemented animals, and OSe-supplemented animals had reduced levels of mRNA encoding proteins known to be upregulated during oxidative stress and cancerous states.

Psychometric properties and osteoprotective behaviors among type 2 diabetic patients: osteoporosis self-efficacy scale Malay version (OSES-M).

PubMed

Abdulameer, S A; Syed Sulaiman, S A; Hassali, M A; Subramaniam, K; Sahib, M N

2013-03-01

In type 2 diabetic patients (T2DM), only 22 % have normal bone mineral density and almost three quarters of the sample population had low self-efficacy towards osteoporosis. These results reflect the need for screening and educational programs to increase the awareness of T2DM towards osteoporosis. Our aim was to translate and examine the psychometric properties of the Malay version of the osteoporosis self-efficacy scale (OSES-M) among T2DM and to determine the best cut-off value with optimum sensitivity and specificity. In addition, to assess factors that affects diabetic patients' osteoporosis self-efficacy. A standard "forward-backward" procedure was used to translate the OSES into Malay language, which was then validated with a convenience sample of 250 T2DM. The sensitivity and specificity of the OSES-M was calculated using receiver operating characteristic curve analysis. Bivariate and multivariate approaches were used to examine multiple independent variables on each dependent variable. The mean score of OSES-M was 731.74 ± 197.15. Fleiss' kappa, content validity ratio range, and content validity index were 0.99, 0.75-1, and 0.96, respectively. Two factors were extracted from exploratory factor analysis and were confirmed through confirmatory factor analysis. Internal consistency and test-retest reliability were 0.92 and 0.86, respectively. The optimum cut-off point of OSES-M to predict osteoporosis/osteopenia was 858. Regression analysis revealed that knowledge, health belief, and some demographic data had an impact on OSES-M. The results show that the OSES-M is a reliable and valid instrument for measuring osteoporosis self-efficacy in the Malaysian clinical setting.

Bond strength of self-etch adhesives after saliva contamination at different application steps.

PubMed

Cobanoglu, N; Unlu, N; Ozer, F F; Blatz, M B

2013-01-01

This study evaluated and compared the effect of saliva contamination and possible decontamination methods on bond strengths of two self-etching adhesive systems (Clearfil SE Bond [CSE], Optibond Solo Plus SE [OSE]). Flat occlusal dentin surfaces were created on 180 extracted human molar teeth. The two bonding systems and corresponding composite resins (Clearfil AP-X, Kerr Point 4) were bonded to the dentin under six surface conditions (n=15/group): group 1 (control): primer/bonding/composite; group 2: saliva/drying/primer/bonding/composite; group 3: primer/saliva/rinsing/drying/primer/bonding/composite; group 4: primer/saliva/rinsing/drying/bonding/composite; group 5: primer/bonding (cured)/saliva/rinsing/drying/primer/bonding/composite; group 6: primer/bonding (cured)/saliva/removing contaminated layer with a bur/rinsing/drying/primer/bonding/composite. Shear bond strength was tested after specimens were stored in distilled water at 37°C for 24 hours. One-way analysis of variance and Tukey post hoc tests were used for statistical analyses. For CSE, groups 2, 3, and 4 and for OSE, groups 6, 2, and 4 showed significantly lower bond strengths than the control group (p<0.05). CSE groups 5 and 6 and OSE groups 3 and 5 revealed bond strengths similar to the control. When saliva contamination occurred after light polymerization of the bonding agent, repeating the bonding procedure recovered the bonding capacity of both self-etch adhesives. However, saliva contamination before or after primer application negatively affected their bond strength.

Effects of osmotic swelling on voltage-gated calcium channel currents in rat anterior pituitary cells.

PubMed

Ben-Tabou De-Leon, Shlomo; Blotnick, Edna; Nussinovitch, Itzhak

2003-10-01

Decrease in extracellular osmolarity ([Os]e) results in stimulation of hormone secretion from pituitary cells. Different mechanisms can account for this stimulation of hormone secretion. In this study we examined the possibility that hyposmolarity directly modulates voltage-gated calcium influx in pituitary cells. The effects of hyposmolarity on L-type (IL) and T-type (IT) calcium currents in pituitary cells were investigated by using two hyposmotic stimuli, moderate (18-22% decrease in [Os]e) and strong (31-32% decrease in [Os]e). Exposure to moderate hyposmotic stimuli resulted in three response types in IL (a decrease, a biphasic effect, and an increase in IL) and in increase in IT. Exposure to strong hyposmotic stimuli resulted only in increases in both IL and IT. Similarly, in intact pituitary cells (perforated patch method), exposure to either moderate or strong hyposmotic stimuli resulted only in increases in both IL and IT. Thus it appears that the main effect of decrease in [Os]e is increase in calcium channel currents. This increase was differential (IL were more sensitive than IT) and voltage independent. In addition, we show that these hyposmotic effects cannot be explained by activation of an anionic conductance or by an increase in cell membrane surface area. In conclusion, this study shows that hyposmotic swelling of pituitary cells can directly modulate voltage-gated calcium influx. This hyposmotic modulation of IL and IT may contribute to the previously reported hyposmotic stimulation of hormone secretion. The mechanisms underlying these hyposmotic effects and their possible physiological relevance are discussed.

Imaging of oxidation-specific epitopes with targeted nanoparticles to detect high-risk atherosclerotic lesions: Progress and future directions

PubMed Central

Briley-Saebo, Karen; Yeang, Calvin; Witztum, Joseph L.; Tsimikas, Sotirios

2014-01-01

Oxidation-specific epitopes (OSE) within developing atherosclerotic lesions are key antigens that drive innate and adaptive immune responses in atherosclerosis, leading to chronic inflammation. Oxidized phospholipids and malondialdehyde-lysine epitopes are well-characterized OSE present in human atherosclerotic lesions, particularly in pathologically defined vulnerable plaques. Using murine and human OSE-specific antibodies as targeting agents, we have developed radionuclide and magnetic resonance based nanoparticles, containing gadolinium, manganese or lipid-coated ultrasmall superparamagnetic iron oxide, to noninvasively image OSE within experimental atherosclerotic lesions. These methods quantitate plaque burden, allow detection of lesion progression and regression, plaque stabilization, and accumulation of OSE within macrophage-rich areas of the artery wall, suggesting they detect the most active lesions. Future studies will focus on using “natural” antibodies, lipopeptides and mimotopes for imaging applications. These approaches should enhance the clinical translation of this technique to image, monitor, evaluate efficacy of novel therapeutic agents and guide optimal therapy of high-risk atherosclerotic lesions. PMID:25297940

Oxidation-specific epitopes restrain bone formation.

PubMed

Ambrogini, Elena; Que, Xuchu; Wang, Shuling; Yamaguchi, Fumihiro; Weinstein, Robert S; Tsimikas, Sotirios; Manolagas, Stavros C; Witztum, Joseph L; Jilka, Robert L

2018-06-06

Atherosclerosis and osteoporosis are epidemiologically linked and oxidation specific epitopes (OSEs), such as phosphocholine (PC) of oxidized phospholipids (PC-OxPL) and malondialdehyde (MDA), are pathogenic in both. The proatherogenic effects of OSEs are opposed by innate immune antibodies. Here we show that high-fat diet (HFD)-induced bone loss is attenuated in mice expressing a single chain variable region fragment of the IgM E06 (E06-scFv) that neutralizes PC-OxPL, by increasing osteoblast number and stimulating bone formation. Similarly, HFD-induced bone loss is attenuated in mice expressing IK17-scFv, which neutralizes MDA. Notably, E06-scFv also increases bone mass in mice fed a normal diet. Moreover, the levels of anti-PC IgM decrease in aged mice. We conclude that OSEs, whether produced chronically or increased by HFD, restrain bone formation, and that diminished defense against OSEs may contribute to age-related bone loss. Anti-OSEs, therefore, may represent a novel therapeutic approach against osteoporosis and atherosclerosis simultaneously.

Expanded prediction equations of human sweat loss and water needs.

PubMed

Gonzalez, R R; Cheuvront, S N; Montain, S J; Goodman, D A; Blanchard, L A; Berglund, L G; Sawka, M N

2009-08-01

The Institute of Medicine expressed a need for improved sweating rate (msw) prediction models that calculate hourly and daily water needs based on metabolic rate, clothing, and environment. More than 25 years ago, the original Shapiro prediction equation (OSE) was formulated as msw (g.m(-2).h(-1))=27.9.Ereq.(Emax)(-0.455), where Ereq is required evaporative heat loss and Emax is maximum evaporative power of the environment; OSE was developed for a limited set of environments, exposures times, and clothing systems. Recent evidence shows that OSE often overpredicts fluid needs. Our study developed a corrected OSE and a new msw prediction equation by using independent data sets from a wide range of environmental conditions, metabolic rates (rest to 500 observations) by using a variety of metabolic rates over a range of environmental conditions (ambient temperature, 15-46 degrees C; water vapor pressure, 0.27-4.45 kPa; wind speed, 0.4-2.5 m/s), clothing, and equipment combinations and durations (2-8 h). Data are expressed as grams per square meter per hour and were analyzed using fuzzy piecewise regression. OSE overpredicted sweating rates (P<0.003) compared with observed msw. Both the correction equation (OSEC), msw=147.exp (0.0012.OSE), and a new piecewise (PW) equation, msw=147+1.527.Ereq-0.87.Emax were derived, compared with OSE, and then cross-validated against independent data (21 males and 9 females; >200 observations). OSEC and PW were more accurate predictors of sweating rate (58 and 65% more accurate, P<0.01) and produced minimal error (standard error estimate<100 g.m(-2).h(-1)) for conditions both within and outside the original OSE domain of validity. The new equations provide for more accurate sweat predictions over a broader range of conditions with applications to public health, military, occupational, and sports medicine settings.

Gene expression of porcine blastocysts from gilts fed organic or inorganic selenium and pyridoxine.

PubMed

Dalto, B D; Tsoi, S; Audet, I; Dyck, M K; Foxcroft, G R; Matte, J J

2015-01-01

In this study, we determined how maternal dietary supplementation with pyridoxine combined with different sources of selenium (Se) affected global gene expression of porcine expanded blastocysts (PEB) during pregnancy. Eighteen gilts were randomly assigned to one of the three experimental diets (n=6 per treatment): i) basal diet without supplemental Se or pyridoxine (CONT); ii) CONT+0.3 mg/kg of Na-selenite and 10 mg/kg of HCl-pyridoxine (MSeB610); and iii) CONT+0.3 mg/kg of Se-enriched yeast and 10 mg/kg of HCl-pyridoxine (OSeB610). All gilts were inseminated at their fifth post-pubertal estrus and killed 5 days later for embryo harvesting. A porcine embryo-specific microarray was used to detect differentially gene expression between MSeB610 vs CONT, OSeB610 vs CONT, and OSeB610 vs MSeB610. CONT gilts had lower whole blood Se and erythrocyte pyridoxal-5-P concentrations than supplemented gilts (P<0.05). No treatment effect was observed on blood plasma Se-glutathione peroxidase activity (P=0.57). There were 10, 247, and 96 differentially expressed genes for MSeB610 vs CONT, OSeB610 vs CONT, and OSeB610 vs MSeB610 respectively. No specific biological process was associated with MSeB610 vs CONT. However, for OSeB610 vs CONT, upregulated genes were related with global protein synthesis but not to selenoproteins. The stimulation of some genes related with monooxygenase and thioredoxin families was confirmed by quantitative real-time RT-PCR. In conclusion, OSeB610 affects PEB metabolism more markedly than MSeB610. Neither Se sources with pyridoxine influenced the Se-glutathione peroxidase metabolic pathway in the PEB, but OSeB610 selectively stimulated genes involved with antioxidant defense. © 2015 Society for Reproduction and Fertility.

Expression pattern of RAGE and IGF-1 in the human fetal ovary and ovarian serous carcinoma.

PubMed

Poljicanin, Ana; Filipovic, Natalija; Vukusic Pusic, Tanja; Soljic, Violeta; Caric, Ana; Saraga-Babic, Mirna; Vukojevic, Katarina

2015-01-01

The expression pattern of RAGE and IGF-1 proteins in different ovarian cell lineages was histologically analyzed in six fetal, nine adult human ovaries, and nine serous ovarian carcinomas (OSC) using immunohistochemical methods. Mild expression of IGF-1 in ovarian surface epithelium (Ose) and oocytes in the 15-week human ovaries increased to moderate or strong in the stromal cells, oocytes and follicular cells in week 22. Occasional mild RAGE expression was observed in Ose during week 15, while strong expression characterized primordial follicles in week 22. In the reproductive human ovary, IGF-1 was mildly to moderately expressed in all ovarian cell lineages except in theca cells of the tertiary follicle where IGF-1 was negative. RAGE was strongly positive in the granulosa cells and some theca cells of the tertiary follicle, while negative to mildly positive in all cells of the secondary follicle. In the postmenopausal human ovary IGF-1 and RAGE were mildly expressed in Ose and stroma. In OSC, cells were strongly positive to IGF-1 and RAGE, except for some negative stromal cells. Different levels of IGF-1 and RAGE co-expression characterized fetal ovarian cells during development. In reproductive ovaries, IGF-1 and RAGE were co-localized in the granulosa and theca interna cells of tertiary follicles, while in postmenopausal ovaries and OSC, IGF-1 and RAGE were co-localized in Ose and OSC cells respectively. Our results indicate that intracellular levels of IGF-1 and RAGE protein might regulate the final destiny of the ovarian cell populations prior and during folliculogenesis, possibly controlling the metastatic potential of OSC as well. Copyright © 2015. Published by Elsevier GmbH.

Detecting extrasolar moons akin to solar system satellites with an orbital sampling effect

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heller, René, E-mail: rheller@physics.mcmaster.ca

2014-05-20

Despite years of high accuracy observations, none of the available theoretical techniques has yet allowed the confirmation of a moon beyond the solar system. Methods are currently limited to masses about an order of magnitude higher than the mass of any moon in the solar system. I here present a new method sensitive to exomoons similar to the known moons. Due to the projection of transiting exomoon orbits onto the celestial plane, satellites appear more often at larger separations from their planet. After about a dozen randomly sampled observations, a photometric orbital sampling effect (OSE) starts to appear in themore » phase-folded transit light curve, indicative of the moons' radii and planetary distances. Two additional outcomes of the OSE emerge in the planet's transit timing variations (TTV-OSE) and transit duration variations (TDV-OSE), both of which permit measurements of a moon's mass. The OSE is the first effect that permits characterization of multi-satellite systems. I derive and apply analytical OSE descriptions to simulated transit observations of the Kepler space telescope assuming white noise only. Moons as small as Ganymede may be detectable in the available data, with M stars being their most promising hosts. Exomoons with the ten-fold mass of Ganymede and a similar composition (about 0.86 Earth radii in radius) can most likely be found in the available Kepler data of K stars, including moons in the stellar habitable zone. A future survey with Kepler-class photometry, such as Plato 2.0, and a permanent monitoring of a single field of view over five years or more will very likely discover extrasolar moons via their OSEs.« less

Optical Spring Effect in Micro-Bubble Resonators and Its Application for the Effective Mass Measurement of Optomechanical Resonant Mode.

PubMed

Chen, Zhenmin; Wu, Xiang; Liu, Liying; Xu, Lei

2017-09-30

In this work, we present a novel approach for obtaining the effective mass of mechanical vibration mode in micro-bubble resonators (MBRs). To be specific, the effective mass is deduced from the measurement of optical spring effect (OSE) in MBRs. This approach is demonstrated and applied to analyze the effective mass of hollow MBRs and liquid-filled MBRs, respectively. It is found that the liquid-filled MBRs has significantly stronger OSE and a less effective mass than hollow MBRs, both of the extraordinary behaviors can be beneficial for applications such as mass sensing. Larger OSE from higher order harmonics of the mechanical modes is also observed. Our work paves a way towards the developing of OSE-based high sensitive mass sensor in MBRs.

Simulating Conditional Deterministic Predictability within Ocean Frontogenesis

DTIC Science & Technology

2014-03-26

Prediction System (COAMPS; Hodur, 1997) across the inner domain. The surface wind stress is determined from the atmo- spheric model wind velocity...layers on the light side of the front. Increasing the strength of the down-front wind increases the frontogenesis. Mahadevan and Tandon (2006) showed...Filaments of shallow MLD, large frontogenesis and large surface divergence ( upwelling ) are found in the OSEs, but at different locations and strengths . The

Evidence for the Complexity of MicroRNA-Mediated Regulation in Ovarian Cancer: A Systems Approach

PubMed Central

Shahab, Shubin W.; Matyunina, Lilya V.; Mezencev, Roman; Walker, L. DeEtte; Bowen, Nathan J.; Benigno, Benedict B.; McDonald, John F.

2011-01-01

MicroRNAs (miRNAs) are short (∼22 nucleotides) regulatory RNAs that can modulate gene expression and are aberrantly expressed in many diseases including cancer. Previous studies have shown that miRNAs inhibit the translation and facilitate the degradation of their targeted messenger RNAs (mRNAs) making them attractive candidates for use in cancer therapy. However, the potential clinical utility of miRNAs in cancer therapy rests heavily upon our ability to understand and accurately predict the consequences of fluctuations in levels of miRNAs within the context of complex tumor cells. To evaluate the predictive power of current models, levels of miRNAs and their targeted mRNAs were measured in laser captured micro-dissected (LCM) ovarian cancer epithelial cells (CEPI) and compared with levels present in ovarian surface epithelial cells (OSE). We found that the predicted inverse correlation between changes in levels of miRNAs and levels of their mRNA targets held for only ∼11% of predicted target mRNAs. We demonstrate that this low inverse correlation between changes in levels of miRNAs and their target mRNAs in vivo is not merely an artifact of inaccurate miRNA target predictions but the likely consequence of indirect cellular processes that modulate the regulatory effects of miRNAs in vivo. Our findings underscore the complexities of miRNA-mediated regulation in vivo and the necessity of understanding the basis of these complexities in cancer cells before the therapeutic potential of miRNAs can be fully realized. PMID:21811625

Optical Spring Effect in Micro-Bubble Resonators and Its Application for the Effective Mass Measurement of Optomechanical Resonant Mode

PubMed Central

Chen, Zhenmin; Wu, Xiang; Liu, Liying; Xu, Lei

2017-01-01

In this work, we present a novel approach for obtaining the effective mass of mechanical vibration mode in micro-bubble resonators (MBRs). To be specific, the effective mass is deduced from the measurement of optical spring effect (OSE) in MBRs. This approach is demonstrated and applied to analyze the effective mass of hollow MBRs and liquid-filled MBRs, respectively. It is found that the liquid-filled MBRs has significantly stronger OSE and a less effective mass than hollow MBRs, both of the extraordinary behaviors can be beneficial for applications such as mass sensing. Larger OSE from higher order harmonics of the mechanical modes is also observed. Our work paves a way towards the developing of OSE-based high sensitive mass sensor in MBRs. PMID:28974004

Ocean OSSEs: recent developments and future challenges

NASA Astrophysics Data System (ADS)

Kourafalou, V. H.

2012-12-01

Atmospheric OSSEs have had a much longer history of applications than OSSEs (and OSEs) in oceanography. Long standing challenges include the presence of coastlines and steep bathymetric changes, which require the superposition of a wide variety of space and time scales, leading to difficulties on ocean observation and prediction. For instance, remote sensing is critical for providing a quasi-synoptic oceanographic view, but the coverage is limited at the ocean surface. Conversely, in situ measurements are capable to monitor the entire water column, but at a single location and usually for a specific, short time. Despite these challenges, substantial progress has been made in recent years and international initiatives have provided successful OSSE/OSE examples and formed appropriate forums that helped define the future roadmap. These will be discussed, together with various challenges that require a community effort. Examples include: integrated (remote and in situ) observing system requirements for monitoring large scale and climatic changes, vs. short term variability that is particularly important on the regional and coastal spatial scales; satisfying the needs of both global and regional/coastal nature runs, from development to rigorous evaluation and under a clear definition of metrics; data assimilation in the presence of tides; estimation of real-time river discharges for Earth system modeling. An overview of oceanographic efforts that complement the standard OSSE methodology will also be given. These include ocean array design methods, such as representer-based analysis and adaptive sampling. Exciting new opportunities for both global and regional ocean OSSE/OSE studies have recently become possible with targeted periods of comprehensive data sets, such as the existing Gulf of Mexico observations from multiple sources in the aftermath of the DeepWater Horizon incident and the upcoming airborne AirSWOT, in preparation for the SWOT (Surface Water and Ocean Topography) mission.

Production of bio-sugar and bioethanol from coffee residue (CR) by acid-chlorite pretreatment.

PubMed

Kim, Ho Myeong; Choi, Yong-Soo; Lee, Dae-Seok; Kim, Yong-Hwan; Bae, Hyeun-Jong

2017-07-01

Nowadays, coffee residue (CR) after roasting is recognized as one of the most useful resources in the world for producing the biofuel and bio-materials. In this study, we evaluated the potential of bio-sugar and bioethanol production from acid-chlorite treated CR. Notably, CR treated three times with acid-chlorite after organic solvent extraction (OSE-3), showed the high monosaccharide content, and the efficient sugar conversion yield compared to the other pretreatment conditions. The OSE-3 (6% substrate loading, w/v) can produce bio-sugar (0.568g/g OSE-3). Also, simultaneous saccharification and fermentation (SSF) produced ethanol (0.266g/g OSE-3), and showed an ethanol conversion yield of 73.8% after a 72-h reaction period. These results suggest that acid-chlorite pretreatment can improve the bio-sugar and bioethanol production of CR by removing the phenolic and brown compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bone morphogenetic protein 2 activates Smad6 gene transcription through bone-specific transcription factor Runx2.

PubMed

Wang, Qing; Wei, Xiaochao; Zhu, Tianhui; Zhang, Ming; Shen, Run; Xing, Lianping; O'Keefe, Regis J; Chen, Di

2007-04-06

BMP-2 plays an essential role in osteoblast and chondrocyte differentiation, but its signaling mechanism has not been fully defined. In the present studies, we investigated the mechanism through which BMP-2 activates the Smad6 gene. A -2006/+45 Smad6 promoter-luciferase construct was generated along with deletions and Runx2 binding site mutations to examine the role of Smad1 and Runx2 signaling following BMP-2 stimulation in osteoblasts. Transfection of Runx2 or treatment with BMP-2-stimulated promoter activity of the -2006/+45 and -1191/+45 reporters but not the -829/+45 and -374/+45 reporters. No Smad1/5 binding site is present in the -1191/-829 region of the Smad6 promoter. Mutation of the OSE2-a site (-1036/-1031) completely abolished the stimulatory effect of Runx2 as well as BMP-2 on the -2006/+45 and -1191/+45 Smad6 reporters. Gel shift and chromatin immunoprecipitation (ChIP) assays showed that Runx2 binds the OSE2-a element. ChIP assays demonstrated that Smad1 also interacts with the OSE2-a site at the Smad6 promoter through Runx2. The protein degradation of Runx2 is mediated by the E3 ubiquitin ligase Smurf1. In the present studies, we found that Smurf1 binds the OSE2-a site through Runx2 and inhibits Smad6 gene transcription. Treatment with BMP-2 and transfection of Smad1 abolished Smurf1 binding to the OSE2 site. These results show that Smad1 binding excludes Smurf1 interaction with the OSE2 site and promotes Smad6 gene transcription.

Observation of a second metastable spin-ordered state in ferrimagnet Cu2OSeO3

NASA Astrophysics Data System (ADS)

Huang, C. L.; Tseng, K. F.; Chou, C. C.; Mukherjee, S.; Her, J. L.; Matsuda, Y. H.; Kindo, K.; Berger, H.; Yang, H. D.

2011-02-01

dc and ac magnetization measurements were performed on single-crystal Cu2OSeO3 under magnetic field (H) and hydrostatic pressure (P) conditions. Increasing H shifts the ferrimagnetic transition observed at TC~60 K to a higher-temperature region. Moreover, the TC increases linearly and magnetization is enhanced with P. Features of the ladder in the M-vs-H curve or the peak in the dM/dH-vs-H curve are observed at HSF~0.5 kOe, suggesting a competing ordered state under magnetic fields below TC. Remarkably, a second shoulder is observed at ˜1 kOe in the dM/dH-vs-H curve, revealing another metastable spin-ordered state in Cu2OSeO3. This state is retained and enhanced by applying pressure. As H rises to 55 T, no further slope changes in the M-H curve are observed. These magnetic properties indicate a complex spin orientation in the geometrically spin-frustrated system Cu2OSeO3.

Magnon spectrum of the helimagnetic insulator Cu 2OSeO 3

DOE PAGES

Portnichenko, P. Y.; Romhányi, J.; Onykiienko, Y. A.; ...

2016-02-25

We report that complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu 2OSeO 3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu 2OSeO 3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a modelmore » of entangled Cu 4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu 2OSeO 3 that are essential for understanding its abundant low-temperature magnetically ordered phases.« less

Magnon spectrum of the helimagnetic insulator Cu2OSeO3

PubMed Central

Portnichenko, P. Y.; Romhányi, J.; Onykiienko, Y. A.; Henschel, A.; Schmidt, M.; Cameron, A. S.; Surmach, M. A.; Lim, J. A.; Park, J. T.; Schneidewind, A.; Abernathy, D. L.; Rosner, H.; van den Brink, Jeroen; Inosov, D. S.

2016-01-01

Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu2OSeO3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu2OSeO3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a model of entangled Cu4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu2OSeO3 that are essential for understanding its abundant low-temperature magnetically ordered phases. PMID:26911567

Magnon spectrum of the helimagnetic insulator Cu2OSeO3.

PubMed

Portnichenko, P Y; Romhányi, J; Onykiienko, Y A; Henschel, A; Schmidt, M; Cameron, A S; Surmach, M A; Lim, J A; Park, J T; Schneidewind, A; Abernathy, D L; Rosner, H; van den Brink, Jeroen; Inosov, D S

2016-02-25

Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu2OSeO3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu2OSeO3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a model of entangled Cu4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu2OSeO3 that are essential for understanding its abundant low-temperature magnetically ordered phases.

D-amino acid oxidase gene therapy sensitizes glioma cells to the antiglycolytic effect of 3-bromopyruvate.

PubMed

El Sayed, S M; Abou El-Magd, R M; Shishido, Y; Chung, S P; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

2012-01-01

Glioma tumors are refractory to conventional treatment. Glioblastoma multiforme is the most aggressive type of primary brain tumors in humans. In this study, we introduce oxidative stress-energy depletion (OSED) therapy as a new suggested treatment for glioblastoma. OSED utilizes D-amino acid oxidase (DAO), which is a promising therapeutic protein that induces oxidative stress and apoptosis through generating hydrogen peroxide (H2O2). OSED combines DAO with 3-bromopyruvate (3BP), a hexokinase II (HK II) inhibitor that interferes with Warburg effect, a metabolic alteration of most tumor cells that is characterized by enhanced aerobic glycolysis. Our data revealed that 3BP induced depletion of energetic capabilities of glioma cells. 3BP induced H2O2 production as a novel mechanism of its action. C6 glioma transfected with DAO and treated with D-serine together with 3BP-sensitized glioma cells to 3BP and decreased markedly proliferation, clonogenic power and viability in a three-dimensional tumor model with lesser effect on normal astrocytes. DAO gene therapy using atelocollagen as an in vivo transfection agent proved effective in a glioma tumor model in Sprague-Dawley (SD) rats, especially after combination with 3BP. OSED treatment was safe and tolerable in SD rats. OSED therapy may be a promising therapeutic modality for glioma.

Selenium content in blood fractions and liver of beef heifers is greater with a mix of inorganic/organic or organic versus inorganic supplemental selenium but the time required for maximal assimilation is tissue-specific.

PubMed

Brennan, Kristen M; Burris, Walter R; Boling, James A; Matthews, James C

2011-12-01

Selenium (Se) content of feedstuffs is dependent on the Se level of the soil. Even though Se in grass and forage crops is primarily present in organic forms, Se is commonly supplemented in cattle diets in an inorganic (sodium selenite) form in geographic regions where Se soil concentrations are low. The purpose of this study was to answer two important questions about inorganic (ISe) vs organic (OSe) forms of dietary supplementation of Se (3 mg/day) to growing beef heifers (0.5 kg/day): (1) what would the effect of supplementing Se with an equal blend of ISe:OSe (Mix) have on Se tissue concentrations and (2) how long does it take for the greater assimilation with OSE to occur and stabilize? A long-term (224 day) Se dietary supplementation trial was conducted with serial sampling performed (days 28, 56, 112, and 224) to determine the length of time required to achieve Se supplement (OSE, Mix, and ISe)-dependent changes in Se assimilation in blood fractions and liver tissue. Forty maturing Angus heifers were fed a corn silage-based diet for 98 days with no Se supplementation, and then a cracked corn/cottonseed hull-based diet (basal diet) without Se supplementation for 74 days. Liver biopsies were taken for Se analysis, and heifers were fed the same diet for another 14 days. Heifers were assigned (n = 10) to one of four Se treatment groups such that basal liver Se contents were stratified among groups, and then fed enough of the basal diet (0.08 mg Se per day) and a mineral-vitamin mix that provided 0.16 (control) or 3.0 mg Se per day in ISe (sodium selenite), OSe (Sel-Plex(®)), or Mix (1:1 ISe:OSe) form to support 0.5 kg/day growth for 224 days. More Se was found in whole blood, red blood cells, serum, and liver of Mix and OSe heifers than ISe heifers, and all were greater than control. Se content either increased until day 56 then was stable (liver and plasma), or was stable until day 56 (whole blood) or day 112 (red blood cells) and then increased steadily through day 224, for all supplemental Se treatments. These data indicate that a 1:1 mix (1.5 mg Se:1.5 mg Se) of supplemental ISe and OSe is equal to 3 mg/day OSe supplementation and greater than 3 mg/day ISe supplementation. The data also indicate that Se levels stabilized in liver and plasma by 56 to 112 days whereas whole blood and red blood cell concentrations were still increasing through 224 days of supplementation, regardless of the form of supplemental Se.

Ballistic magnon heat conduction and possible Poiseuille flow in the helimagnetic insulator Cu2OSeO3

NASA Astrophysics Data System (ADS)

Prasai, N.; Trump, B. A.; Marcus, G. G.; Akopyan, A.; Huang, S. X.; McQueen, T. M.; Cohn, J. L.

2017-06-01

We report on the observation of magnon thermal conductivity κm˜70 W/mK near 5 K in the helimagnetic insulator Cu2OSeO3 , exceeding that measured in any other ferromagnet by almost two orders of magnitude. Ballistic, boundary-limited transport for both magnons and phonons is established below 1 K, and Poiseuille flow of magnons is proposed to explain a magnon mean-free path substantially exceeding the specimen width for the least defective specimens in the range 2 K

Unmanned Aviation Systems Models of the Radio Communications Links: Study Results - Appendices Annex 2. Volume 1 and Volume 2

NASA Technical Reports Server (NTRS)

Birr, Richard B.; Spencer, Roy; Murray, Jennifer; Lash, Andrew

2013-01-01

This report describes the analysis of communications between the Control Station and an Unmanned Aircraft (UA) flying in the National Airspace System (NAS). This work is based on the RTCA SC-203 Operational Services and Environment Description (OSED). The OSED document seeks to characterize the highly different attributes of all UAs navigating the airspace and define their relationship to airspace users, air traffic services, and operating environments of the NAS. One goal of this report is to lead to the development of Minimum Aviation System Performance Standards for Control and Communications. This report takes the nine scenarios found in the OSED and analyzes the communication links.

Measuring Student Engagement in the Online Course: The Online Student Engagement Scale (OSE)

ERIC Educational Resources Information Center

Dixson, Marcia D.

2015-01-01

Student engagement is critical to student learning, especially in the online environment, where students can often feel isolated and disconnected. Therefore, teachers and researchers need to be able to measure student engagement. This study provides validation of the Online Student Engagement scale (OSE) by correlating student self-reports of…

Entangled tetrahedron ground state and excitations of the magnetoelectric skyrmion material Cu2OSeO3

NASA Astrophysics Data System (ADS)

Romhányi, Judit; van den Brink, Jeroen; Rousochatzakis, Ioannis

2014-10-01

The strongly correlated cuprate Cu2OSeO3 has been recently identified as the first insulating system exhibiting a skyrmion lattice phase. Using a microscopic multiboson theory for its magnetic ground state and excitations, we establish the presence of two distinct types of modes: a low-energy manifold that includes a gapless Goldstone mode and a set of weakly dispersive high-energy magnons. These spectral features are the most direct signatures of the fact that the essential magnetic building blocks of Cu2OSeO3 are not individual Cu spins, but rather weakly coupled Cu4 tetrahedra. Several of the calculated excitation energies are in excellent agreement with terahertz electron spin resonance, Raman, and far-infrared experiments, while the magnetoelectric effect determined within the present quantum-mechanical framework is also fully consistent with experiments, giving strong evidence in the entangled Cu4 tetrahedra picture of Cu2OSeO3 . The predicted energy and momentum dependence of the dipole and quadrupole spin structure factors call for further experimental tests of this picture.

A second metastable spin-ordered state on ferrimagnetic single crystal Cu2 OSeO 3

NASA Astrophysics Data System (ADS)

Chou, Chih Chieh; Huang, C. L.; Tseng, K. F.; Mukherjee, S.; Her, J. L.; Matsuda, Y. H.; Kindo, K.; Berger, H.; Yang, H. D.

2011-03-01

DC and AC susceptibilities were executed on ferrimagnetic single crystal Cu 2 OSe O3 under magnetic field (H) and hydrostatic pressure (P) circumstance. With increasing H , the ferrimagnetic transition at TC ~ 60 K tends to a higher temperature. Furthermore, the TC rises with a linear slope and magnetization is enhanced with increasing P . Features of the ladder shown in the M vs. H curve or the peak observed in the d M / d H vs. H curve are noted at HSF ~ 0.5 kOe, exhibiting a competing ordered state in magnetic fields below TC . Remarkably, another shoulder is observed at ~ 1 kOe in the d M / d H vs. H curve, revealing a metastable spin ordered state in Cu 2 OSe O3 . In addition, the novel state is retained and enhanced by applied pressure. However, at H up to 55 T, there is no more observable slop change in magnetization. These magnetic properties suggest a complex spin orientation in the spin-frustrated system Cu 2 OSe O3 .

Hepatic transcriptome profiles differ among maturing beef heifers supplemented with inorganic, organic, or mixed (50% inorganic:50% organic) forms of dietary selenium.

PubMed

Matthews, James C; Zhang, Zhi; Patterson, Jennifer D; Bridges, Phillip J; Stromberg, Arnold J; Boling, J A

2014-09-01

Selenium (Se) is an important trace mineral that, due to deficiencies in the soil in many parts of the USA, must be supplemented directly to the diet of foraging cattle. Both organic and inorganic forms of dietary Se supplements are available and commonly used, and it is known that Se form affects tissue assimilation, bioavailability, and physiological responses. However, little is known about the effects of form of dietary Se supplements on gene expression profiles, which ostensibly account for Se form-dependent physiological processes. To determine if hepatic transcriptomes of growing beef (Angus-cross) heifers (0.5 kg gain/day) was altered by form of dietary supplemental Se, none (Control), or 3 mg Se/day as inorganic Se (ISe, sodium selenite), organic (OSe, Sel-Plex®), or a blend of ISe and OSe (1.5 mg:1.5 mg, Mix) Se was fed for 168 days, and the RNA expression profiles from biopsied liver tissues was compared by microarray analysis. The relative abundance of 139 RNA transcripts was affected by Se treatment, with 86 of these with complete gene annotations. Statistical and bioinformatic analysis of the annotated RNA transcripts revealed clear differences among the four Se treatment groups in their hepatic expression profiles, including (1) solely and commonly affected transcripts; (2) Control and OSe profiles being more similar than Mix and ISe treatments; (3) distinct OSe-, Mix-, and ISe-Se treatment-induced "phenotypes" that possessed both common and unique predicted physiological capacities; and (4) expression of three microRNAs were uniquely sensitive to OSe, ISe, or Mix treatments, including increased capacity for redox potential induced by OSe and Mix Se treatments resulting from decreased expression of MiR2300b messenger RNA. These findings indicate that the form of supplemental dietary Se consumed by cattle will affect the composition of liver transcriptomes resulting, presumably, in different physiological capacities.

Multiferroicity in Cu2OSeO3?

NASA Astrophysics Data System (ADS)

Ruff, Eugen; Krohns, Stephan; Berger, Helmuth; Lunkenheimer, Peter; Loidl, Alois

2014-03-01

Topological spin textures in solids are in the focus for applications in future spin-electronic technology, like high-density magnetic storage devices. Prominent materials are metallic alloys with B20 structure, such as MnSi, where skyrmions, vortex-like objects of nanometer scale, have been experimentally detected. In these materials, it is well known that low currents can drive skyrmion switching. In contrast, the discovery of magnetoelectric skyrmions in an insulating chiral-lattice magnet Cu2OSeO3 leads to another promising route to electric control. This system is suggested to carry a local electric dipole, which implies that the skyrmions should be controllable by the external electric field without losses due to joule heating. Here we provide a thorough analysis of the magnetic and polar phases, using SQUID and pyrocurrent measurements. In order to investigate the possible ferroelectric properties of Cu2OSeO3, we have performed dielectric spectroscopy in various magnetic fields in a broad frequency range below 70 K. Combining all these different techniques, we address the question whether Cu2OSeO3 is magnetoelectric or multiferroic. This work was supported by the DFG via TRR 80.

B-1 Cell Immunoglobulin Directed Against Oxidation-Specific Epitopes

PubMed Central

Tsiantoulas, Dimitrios; Gruber, Sabrina; Binder, Christoph J.

2013-01-01

Natural antibodies (NAbs) are pre-existing antibodies with germline origin that arise in the absence of previous exposure to foreign antigens. NAbs are produced by B-1 lymphocytes and are primarily of the IgM isotype. There is accumulating evidence that – in addition to their role in antimicrobial host defense – NAbs exhibit important housekeeping functions by facilitating the non-immunogenic clearance of apoptotic cells as well as the removal of (neo-)self antigens. These properties are largely mediated by the ability of NAbs to recognize highly conserved and endogenously generated structures, which are exemplified by so-called oxidation-specific epitopes (OSEs) that are products of lipid peroxidation. The generation of OSEs as well as their interaction with the immune system have been studied extensively in the context of atherosclerosis, a chronic inflammatory disease of the vascular wall that is characterized by the accumulation of cellular debris and oxidized low-density lipoproteins (OxLDL). Both apoptotic cells as well as OxLDL carry OSEs that are targeted by NAbs. Therefore, OSEs represent stress-induced neo self-structures that mediate recognition of metabolic waste (e.g., cellular debris) by NAbs, allowing its safe disposal, which has fundamental implications in health and disease. PMID:23316200

Structural characterization of selenium and selenium-diiodine analogues of the antithyroid drug 6-n-propyl-2-thiouracil and its alkyl derivatives.

PubMed

Antoniadis, Constantinos D; Blake, Alexander J; Hadjikakou, Sotiris K; Hadjiliadis, Nick; Hubberstey, Peter; Schröder, Martin; Wilson, Claire

2006-08-01

The structures of four selenium analogues of the antithyroid drug 6-n-propyl-2-thiouracil [systematic name: 2,3-dihydro-6-n-propyl-2-thioxopyrimidin-4(1H)-one], namely 6-methyl-2-selenouracil, C(5)H(6)N(2)OSe (1), 6-ethyl-2-selenouracil, C(6)H(8)N(2)OSe (2), 6-n-propyl-2-selenouracil, C(7)H(10)N(2)OSe (3), and 6-isopropyl-2-selenouracil, C(7)H(10)N(2)OSe (4), are described, along with that of the dichloromethane monosolvate of 6-isopropyl-2-selenouracil, C(7)H(10)N(2)OSe.CH(2)Cl(2) (4.CH(2)Cl(2)). The extended structure of (1) is a two-dimensional sheet of topology 6(3) with a brick-wall architecture. The extended structures of (2) and (4) are analogous, being based on a chain of eight-membered R(8)(6)(32) hydrogen-bonded rings. In (3) and (4.CH(2)Cl(2)), R(2)(2)(8) hydrogen bonding links molecules into chains. 6-n-Propyl-2-selenouracil.I(2), C(7)H(10)N(2)OSe.I(2) (7), is a charge-transfer complex with a ;spoke' structure, the extended structure of which is based on a linear chain formed principally by intermolecular N-H...O hydrogen bonds. Re-crystallization of 6-ethyl-2-selenouracil or (7) from acetone gave crystals of the diselenides [N-(6'-ethyl-4'-pyrimidone)(6-ethyl-2-selenouracil)(2)(Se-Se)].2H(2)O (9.2H(2)O) or [N-(6'-n-propyl-4'-pyrimidone)(6-n-propyl-2-selenouracil)(2)(Se-Se)] (10), respectively: these have similar extended chain structures formed via N-H...O and C-H...O hydrogen bonds, stacked to give two-dimensional sheets. Re-crystallization of (7) from methanol/acetonitrile led via deselenation to the formation of crystals of 6-n-propyl-2-uracil (11), in which six symmetry-related molecules combine to form a six-membered R(6)(6)(24) hydrogen-bonded ring, with each pair of molecules linked by an R(2)(2)(8) motif.

Attenuation of autoimmune responses to oxidative specific epitopes, but not nitroso-adducts, is associated with a better clinical outcome in Myalgic Encephalomyelitis/chronic fatigue syndrome.

PubMed

Maes, Michael; Leunis, Jean-Claude

2014-01-01

There is evidence that inflammatory, oxidative and nitrosative stress (IO&NS) pathways participate in the pathophysiology of a subgroup of patients with Myalgic Encephalomyelitis/chronic fatigue syndrome (ME/CFS). Increased IgM-related autoimmune responses to oxidative specific epitopes (OSEs), including malondialdehyde (MDA), oleic acid and phosphatidyl inositol (Pi), and nitroso-(NO)-adducts, including NO-tryptophan (NOW), NO-arginine and NO-cysteinyl, are frequently observed in ME/CFS. Autoimmune responses in ME/CFS may be driven by increased bacterial translocation as measured by IgM and IgA responses to LPS of gram negative bacteria. The aim of this study is to examine whether IgM responses to OSEs and NO-adducts are related to a better outcome as measured by the Fibromyalgia and Fatigue Rating Scale (FF). 76 ME/CFS patients with initially abnormal autoimmune responses were treated with care-as-usual, including nutraceuticals with anti-IO&NS effects (NAIOS), such as L-carnitine, coenzyme Q10, taurine + lipoic acid, with or without curcumine + quercitine or N-acetyl-cysteine, zinc + glutamine. We found that use of these NAIOS was associated with highly significant reductions in initially increased IgM-mediated autoimmune responses to OSEs and NO-adducts. A greater reduction in autoimmune responses to OSEs during intake of these NAIOS was associated with a lower FF score. Reductions in IgM responses to oleic acid, MDA and Pi, but not in any of the NO-adducts, were associated with reductions in severity of illness. These associations remained significant after adjusting for possible effects of increased bacterial translocation (leaky gut). Our results show that autoimmune responses to OSEs are involved in the pathophysiology of ME/CFS and that these pathways are a new drug target in a subgroup of ME/CFS patients. Although hypernitrosylation and nitrosative stress play a role in ME/CFS, reductions in these pathways are not associated with lowered severity of illness. Randomized controlled trials with NAIOS should be carried out in the subgroup of ME/CFS patients with initially increased autoimmune responses to OSEs.

OntoStudyEdit: a new approach for ontology-based representation and management of metadata in clinical and epidemiological research.

PubMed

Uciteli, Alexandr; Herre, Heinrich

2015-01-01

The specification of metadata in clinical and epidemiological study projects absorbs significant expense. The validity and quality of the collected data depend heavily on the precise and semantical correct representation of their metadata. In various research organizations, which are planning and coordinating studies, the required metadata are specified differently, depending on many conditions, e.g., on the used study management software. The latter does not always meet the needs of a particular research organization, e.g., with respect to the relevant metadata attributes and structuring possibilities. The objective of the research, set forth in this paper, is the development of a new approach for ontology-based representation and management of metadata. The basic features of this approach are demonstrated by the software tool OntoStudyEdit (OSE). The OSE is designed and developed according to the three ontology method. This method for developing software is based on the interactions of three different kinds of ontologies: a task ontology, a domain ontology and a top-level ontology. The OSE can be easily adapted to different requirements, and it supports an ontologically founded representation and efficient management of metadata. The metadata specifications can by imported from various sources; they can be edited with the OSE, and they can be exported in/to several formats, which are used, e.g., by different study management software. Advantages of this approach are the adaptability of the OSE by integrating suitable domain ontologies, the ontological specification of mappings between the import/export formats and the DO, the specification of the study metadata in a uniform manner and its reuse in different research projects, and an intuitive data entry for non-expert users.

Optimization-based scatter estimation using primary modulation for computed tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Yi; Ma, Jingchen; Zhao, Jun, E-mail: junzhao

Purpose: Scatter reduces the image quality in computed tomography (CT), but scatter correction remains a challenge. A previously proposed primary modulation method simultaneously obtains the primary and scatter in a single scan. However, separating the scatter and primary in primary modulation is challenging because it is an underdetermined problem. In this study, an optimization-based scatter estimation (OSE) algorithm is proposed to estimate and correct scatter. Methods: In the concept of primary modulation, the primary is modulated, but the scatter remains smooth by inserting a modulator between the x-ray source and the object. In the proposed algorithm, an objective function ismore » designed for separating the scatter and primary. Prior knowledge is incorporated in the optimization-based framework to improve the accuracy of the estimation: (1) the primary is always positive; (2) the primary is locally smooth and the scatter is smooth; (3) the location of penumbra can be determined; and (4) the scatter-contaminated data provide knowledge about which part is smooth. Results: The simulation study shows that the edge-preserving weighting in OSE improves the estimation accuracy near the object boundary. Simulation study also demonstrates that OSE outperforms the two existing primary modulation algorithms for most regions of interest in terms of the CT number accuracy and noise. The proposed method was tested on a clinical cone beam CT, demonstrating that OSE corrects the scatter even when the modulator is not accurately registered. Conclusions: The proposed OSE algorithm improves the robustness and accuracy in scatter estimation and correction. This method is promising for scatter correction of various kinds of x-ray imaging modalities, such as x-ray radiography, cone beam CT, and the fourth-generation CT.« less

The Impact of Current and Future Polar Orbiting Satellite Data on Numerical Weather Prediction at NASA/GSFC

NASA Technical Reports Server (NTRS)

Atlas, Robert

2004-01-01

The lack of adequate observational data continues to be recognized as a major factor limiting both atmospheric research and numerical prediction on a variety of temporal and spatial scales. Since the advent of meteorological satellites in the 1960's, a considerable research effort has been directed toward the design of space-borne meteorological sensors, the development of optimal methods for the utilization of these data, (and an assessment of the influence of existing satellite data and the potential influence of future satellite observations on numerical weather prediction. This has included both Observing System Experiments (OSEs) and Observing System Simulation Experiments (OSSEs). OSEs are conducted to evaluate the impact of specific observations or classes of observations on analyses and forecasts. While OSEs are performed with existing data, OSSEs are conducted to evaluate the potential for future observing systems to improve-NWP, as well as to evaluate trade-offs in observing system design, and to develop and test improved methods for data assimilation. At the conference, results from OSEs to evaluate satellite data sets that have recently become available to the global observing system, such as AIRS and Seawinds, and results from OSSEs to determine the potential impact of space-based lidar winds will be presented.

IUS (Inertial Upper Stage)/SRM-2 Nozzle Thermal Assessment

DTIC Science & Technology

1984-12-01

design where this could occur:,(see figure 1) 1)(1) The nose cap carbon phenolic to silica phenolic bond surface where temperatures were p:edicted to...contact only with the carbon phenolic r.ose cap and the carbon- carbon integral throat entrance. Although the carbon phenolic is impervious to gas flow...between the housing and silica phenolic liner. After the baseline (BL-l) motor firing, inspection of the gratoil seal area revealed erosion and a hole

Evaluation of tropical Pacific observing systems using NCEP and GFDL ocean data assimilation systems

NASA Astrophysics Data System (ADS)

Xue, Yan; Wen, Caihong; Yang, Xiaosong; Behringer, David; Kumar, Arun; Vecchi, Gabriel; Rosati, Anthony; Gudgel, Rich

2017-08-01

The TAO/TRITON array is the cornerstone of the tropical Pacific and ENSO observing system. Motivated by the recent rapid decline of the TAO/TRITON array, the potential utility of TAO/TRITON was assessed for ENSO monitoring and prediction. The analysis focused on the period when observations from Argo floats were also available. We coordinated observing system experiments (OSEs) using the global ocean data assimilation system (GODAS) from the National Centers for Environmental Prediction and the ensemble coupled data assimilation (ECDA) from the Geophysical Fluid Dynamics Laboratory for the period 2004-2011. Four OSE simulations were conducted with inclusion of different subsets of in situ profiles: all profiles (XBT, moorings, Argo), all except the moorings, all except the Argo and no profiles. For evaluation of the OSE simulations, we examined the mean bias, standard deviation difference, root-mean-square difference (RMSD) and anomaly correlation against observations and objective analyses. Without assimilation of in situ observations, both GODAS and ECDA had large mean biases and RMSD in all variables. Assimilation of all in situ data significantly reduced mean biases and RMSD in all variables except zonal current at the equator. For GODAS, the mooring data is critical in constraining temperature in the eastern and northwestern tropical Pacific, while for ECDA both the mooring and Argo data is needed in constraining temperature in the western tropical Pacific. The Argo data is critical in constraining temperature in off-equatorial regions for both GODAS and ECDA. For constraining salinity, sea surface height and surface current analysis, the influence of Argo data was more pronounced. In addition, the salinity data from the TRITON buoys played an important role in constraining salinity in the western Pacific. GODAS was more sensitive to withholding Argo data in off-equatorial regions than ECDA because it relied on local observations to correct model biases and there were few XBT profiles in those regions. The results suggest that multiple ocean data assimilation systems should be used to assess sensitivity of ocean analyses to changes in the distribution of ocean observations to get more robust results that can guide the design of future tropical Pacific observing systems.

Inspection Tools

NASA Astrophysics Data System (ADS)

1989-01-01

A "NASA Tech Briefs" article describing an inspection tool and technique known as Optically Stimulated Electron Emission (OSEE) led to the formation of Photo Acoustic Technology, Inc. (PAT). PAT produces sensors and scanning systems which assure surface cleanliness prior to bonding, coating, painting, etc. The company's OP1000 series realtime pre-processing detection capability assures 100 percent surface quality testing. The technique involves brief exposure of the inspection surface to ultraviolet radiation. The energy interacts with the surface layer, causing free electrons to be emitted from the surface to be picked up by the detector. When contamination is present, it interferes with the electron flow in proportion to the thickness of the contaminant layer enabling measurement by system signal output. OP1000 systems operate in conventional atmospheres on all types of material and detect both organic and inorganic contamination.

Surface Currents. East Central Indian Ocean Including the East Indian Archipelago (Indonesia)

DTIC Science & Technology

1977-08-01

AKAX EXPLORATION INC. FOREIGN HYDROGRAPHER/R, A. N. DEPT. TRANSPORTATIO&AUSTRLIA RKAD hi TRUC"TONSREPORT DOCUMENTATION PAGE aRo E COMPLITMG PORN 20...thirties... DO Io+.u 1473 boI o O ovc ois LCZ S/4 1 32-a 0145 01 S C UR IT Y CL A SSIFIC AT IO N O f H IS P AG E (34.44 4 8 0 0R C S A OSE[CURIlTY cLAS

Heterogeneous VM Replication: A New Approach to Intrusion Detection, Active Response and Recovery in Cloud Data Centers

DTIC Science & Technology

2015-08-17

from the same execution history, and cost-effective active response by proactively setting up standby VM replicas: migration from a compromised VM...the guest OSes system call code to be reused inside a “shadowed” portion of the context of the out-of- guest inspection program. Besides...by the rootkits in cloud environments. RootkitDet detects rootkits by identifying suspicious code region in the kernel space of guest OSes through

Comparative study of helimagnets MnSi and Cu2OSeO3 at high pressures

NASA Astrophysics Data System (ADS)

Stishov, Sergei; Sidorov, Vladimir; Petrova, Alla; Berdonosov, Peter; Dolgikh, Valery

2014-03-01

The heat capacity of helical magnets Cu2OSeO3 and MnSi has been investigated at high pressures by the ac-calorimetric technique. Despite the differing nature of their magnetic moments, Cu2OSeO3 and MnSi demonstrate a surprising similarity in behavior of their magnetic and thermodynamic properties at the phase transition. Two characteristic features of the heat capacity at the phase transitions of both substances (peak and shoulder) behave also in a similar way at high pressures if analyzed as a function of temperature. This probably implies that the longitudinal spin fluctuations typical of weak itinerant magnets like MnSi contribute little to the phase transition. The shoulders of the heat capacity curves shrink with decreasing temperature suggesting that they arise from classical fluctuations. In case of MnSi the sharp peak and shoulder at the heat capacity disappear simultaneously probably signifying the existence of a tricritical point and confirming the fluctuation nature of the first order phase transition in MnSi as well as in Cu2OSeO3. This work was supported by the Russian Foundation for Basic Research (grant 12-02-00376-a, 12-03-92604), Program of the Physics Department of RAS on Strongly Correlated Electron Systems and Program of the Presidium of RAS on Strongly Compressed Matter.

Out-of-Sample Extrapolation utilizing Semi-Supervised Manifold Learning (OSE-SSL): Content Based Image Retrieval for Histopathology Images

PubMed Central

Sparks, Rachel; Madabhushi, Anant

2016-01-01

Content-based image retrieval (CBIR) retrieves database images most similar to the query image by (1) extracting quantitative image descriptors and (2) calculating similarity between database and query image descriptors. Recently, manifold learning (ML) has been used to perform CBIR in a low dimensional representation of the high dimensional image descriptor space to avoid the curse of dimensionality. ML schemes are computationally expensive, requiring an eigenvalue decomposition (EVD) for every new query image to learn its low dimensional representation. We present out-of-sample extrapolation utilizing semi-supervised ML (OSE-SSL) to learn the low dimensional representation without recomputing the EVD for each query image. OSE-SSL incorporates semantic information, partial class label, into a ML scheme such that the low dimensional representation co-localizes semantically similar images. In the context of prostate histopathology, gland morphology is an integral component of the Gleason score which enables discrimination between prostate cancer aggressiveness. Images are represented by shape features extracted from the prostate gland. CBIR with OSE-SSL for prostate histology obtained from 58 patient studies, yielded an area under the precision recall curve (AUPRC) of 0.53 ± 0.03 comparatively a CBIR with Principal Component Analysis (PCA) to learn a low dimensional space yielded an AUPRC of 0.44 ± 0.01. PMID:27264985

Exercise initiated after the onset of insulin resistance improves trabecular microarchitecture and cortical bone biomechanics of the tibia in hyperphagic Otsuka Long Evans Tokushima Fatty rats.

PubMed

Ortinau, Laura C; Linden, Melissa A; Dirkes, Rebecca K; Rector, R Scott; Hinton, Pamela S

2017-10-01

The present study extends our previous findings that exercise, which prevents the onset of insulin resistance and type 2 diabetes (T2D), also prevents the detrimental effects of T2D on whole-bone and tissue-level strength. Our objective was to determine whether exercise improves bone's structural and material properties if insulin resistance is already present in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The OLETF rat is hyperphagic due to a loss-of-function mutation in cholecystokinin-1 receptor (CCK-1 receptor), which leads to progressive obesity, insulin resistance and T2D after the majority of skeletal growth is complete. Because exercise reduces body mass, which is a significant determinant of bone strength, we used a body-mass-matched caloric-restricted control to isolate body-mass-independent effects of exercise on bone. Eight-wk old, male OLETF rats were fed ad libitum until onset of hyperglycemia (20weeks of age), at which time they were randomly assigned to three groups: ad libitum fed, sedentary (O-SED); ad libitum fed, treadmill running (O-EX); or, sedentary, mild caloric restriction to match body mass of O-EX (O-CR). Long-Evans Tokushima Otsuka rats served as the normophagic, normoglycemic controls (L-SED). At 32weeks of age, O-SED rats had T2D as evidenced by hyperglycemia and a significant reduction in fasting insulin compared to OLETFs at 20weeks of age. O-SED rats also had reduced total body bone mineral content (BMC), increased C-terminal telopeptide of type I collagen (CTx)/tartrate resistant acid phosphatase isoform 5b (TRAP5b), decreased N-terminal propeptide of type I procollagen (P1NP), reduced percent cancellous bone volume (BV/TV), trabecular number (Tb.N) and increased trabecular separation (Tb.Sp) and structural model index (SMI) of the proximal tibia compared to L-SED. T2D also adversely affected biomechanical properties of the tibial diaphysis, and serum sclerostin was increased and β-catenin, runt-related transcription factor 2 (Runx2) and insulin-like growth factor-I (IGF-I) protein expression in bone were reduced in O-SED vs. L-SED. O-EX or O-CR had greater total body bone mineral density (BMD) and BMC, and BV/TV, Tb.N, Tb.Sp, and SMI compared to O-SED. O-EX had lower CTx and CR greater P1NP relative to O-SED. O-EX, not O-CR, had greater cortical thickness and area, and improved whole-bone and tissue-level biomechanical properties associated with a 4-fold increase in cortical bone β-catenin protein expression vs. O-SED. In summary, EX or CR initiated after the onset of insulin resistance preserved cancellous bone volume and structure, and EX elicited additional benefits in cortical bone. Copyright © 2017 Elsevier Inc. All rights reserved.

Growth and Characterization of the p-type Semiconductors Tin Sulfide and Bismuth Copper Oxy Selenide

NASA Astrophysics Data System (ADS)

Francis, Jason

BiCuOSe and SnS are layered, moderate band gap (epsilon G ≈ 1 eV) semiconductors that exhibit intrinsic p type conductivity. Doping of BiCuOSe with Ca results in a slight expansion of the lattice and an increase of the hole concentration from 10 18 cm--3 to greater than 1020 cm --3. The large carrier density in undoped films is the result of copper vacancies. Mobility is unaffected by doping, remaining constant at 1.5 cm2V--1s--1 in both undoped and doped films, because the Bi-O layers serve as the source of carriers, while transport occurs within the Cu-Se layers. Bi possesses a 6s2 lone pair that was expected to hybridize with the oxygen p states at the top of the valence band, resulting in high hole mobility as compared to similar materials such as LaCuOSe, which lack this lone pair. However, both LaCuOSe and BiCuOSe have similar hole mobility. X-ray absorption and emission spectroscopy, combined with density functional theory calculations, reveal that the Bi 6 s states contribute deep within the valence band, forming bonding and anti-bonding states with O 2p at 11 eV and 3 eV below the valence band maximum, respectively. Hence, the Bi lone pair does not contribute at the top of the valence band and does not enhance the hole mobility. The Bi 6p states contribute at the bottom of the conduction band, resulting in a smaller band gap for BiCuOSe than LaCuOSe (1 eV vs. 3 eV). SnS is a potential photovoltaic absorber composed of weakly coupled layers stacked along the long axis. This weak coupling results in the formation of strongly oriented films on amorphous substrates. The optical band gap is 1.2 eV, in agreement with GW calculations. Absorption reaches 105 cm--1 within 0.5 eV of the band gap. The p type conduction arises from energetically favorable tin vacancies. Variation of growth conditions yields carrier densities of 1014 -- 1016 cm--3 and hole mobility of 7 -- 15 cm2V--1s--1. SnS was alloyed with rocksalt CaS, which was predicted to form a rocksalt structure when the calcium content is increased past 18%. Films of Sn1--x CaxS with x from 0.4 to 0.9 adopt the rocksalt structure with a band gap of 1.1-1.3 eV, with absorption greater than 105 cm--1 within about 0.7 eV of the band gap. The lattice contracts as the calcium content of the films is increased, reaching 5.7 A when x = 0.93. Films are highly insulating, but Seebeck measurements do indicate p type conduction.

Materials surface contamination analysis

NASA Technical Reports Server (NTRS)

Workman, Gary L.; Arendale, William F.

1992-01-01

The original research objective was to demonstrate the ability of optical fiber spectrometry to determine contamination levels on solid rocket motor cases in order to identify surface conditions which may result in poor bonds during production. The capability of using the spectral features to identify contaminants with other sensors which might only indicate a potential contamination level provides a real enhancement to current inspection systems such as Optical Stimulated Electron Emission (OSEE). The optical fiber probe can easily fit into the same scanning fixtures as the OSEE. The initial data obtained using the Guided Wave Model 260 spectrophotometer was primarily focused on determining spectra of potential contaminants such as HD2 grease, silicones, etc. However, once we began taking data and applying multivariate analysis techniques, using a program that can handle very large data sets, i.e., Unscrambler 2, it became apparent that the techniques also might provide a nice scientific tool for determining oxidation and chemisorption rates under controlled conditions. As the ultimate power of the technique became recognized, considering that the chemical system which was most frequently studied in this work is water + D6AC steel, we became very interested in trying the spectroscopic techniques to solve a broad range of problems. The complexity of the observed spectra for the D6AC + water system is due to overlaps between the water peaks, the resulting chemisorbed species, and products of reaction which also contain OH stretching bands. Unscrambling these spectral features, without knowledge of the specific species involved, has proven to be a formidable task.

How Does the Macula Protect Itself from Oxidative Stress?

PubMed Central

Handa, James T.

2012-01-01

Oxidative stress has been hypothesized to contribute to the development of age-related macular degeneration (AMD), the most common cause of blindness in the United States. At present, there is no treatment for early disease. Reactive oxygen species (ROS) play a physiological role in the retinal pigment epithelium (RPE), a key cell type in this disease, but with excessive ROS, oxidative damage or excessive innate immune system activation can result. The RPE has developed a robust antioxidant system driven by the transcription factor Nrf2. Impaired Nrf2 signaling can lead to oxidative damage or activate the innate immune response, both of which can lead to RPE apoptosis, a defining change in AMD. Several mouse models simulating environmental stressors or targeting specific antioxidant enzymes such as superoxide dismutase or Nrf2, have simulated some of the features of AMD. While ROS are short-lived, oxidatively damaged molecules termed oxidation specific epitopes (OSEs), can be long-lived and a source of chronic stress that activates the innate immune system through pattern recognition receptors (PRRs). The macula accumulates a number of OSEs including carboxyethylpyrrole, malondialdehyde, 4-hydroxynonenal, and advanced glycation endproducts, as well as their respective neutralizing PRRs. Excessive accumulation of OSEs results in pathologic immune activation. For example, mice immunized with the carboxyethylpyrrole develop cardinal features of AMD. Regulating ROS in the RPE by modulating antioxidant systems or neutralizing OSEs through an appropriate innate immune response are potential modalities to treat or prevent early AMD. PMID:22503691

How does the macula protect itself from oxidative stress?

PubMed

Handa, James T

2012-08-01

Oxidative stress has been hypothesized to contribute to the development of age-related macular degeneration (AMD), the most common cause of blindness in the United States. At present, there is no treatment for early disease. Reactive oxygen species (ROS) play a physiological role in the retinal pigment epithelium (RPE), a key cell type in this disease, but with excessive ROS, oxidative damage or excessive innate immune system activation can result. The RPE has developed a robust antioxidant system driven by the transcription factor Nrf2. Impaired Nrf2 signaling can lead to oxidative damage or activate the innate immune response, both of which can lead to RPE apoptosis, a defining change in AMD. Several mouse models simulating environmental stressors or targeting specific antioxidant enzymes such as superoxide dismutase or Nrf2, have simulated some of the features of AMD. While ROS are short-lived, oxidatively damaged molecules termed oxidation specific epitopes (OSEs), can be long-lived and a source of chronic stress that activates the innate immune system through pattern recognition receptors (PRRs). The macula accumulates a number of OSEs including carboxyethylpyrrole, malondialdehyde, 4-hydroxynonenal, and advanced glycation endproducts, as well as their respective neutralizing PRRs. Excessive accumulation of OSEs results in pathologic immune activation. For example, mice immunized with the carboxyethylpyrrole develop cardinal features of AMD. Regulating ROS in the RPE by modulating antioxidant systems or neutralizing OSEs through an appropriate innate immune response are potential modalities to treat or prevent early AMD. Copyright © 2012 Elsevier Ltd. All rights reserved.

Direct Observation of Twisted Surface skyrmions in Bulk Crystals

NASA Astrophysics Data System (ADS)

Zhang, S. L.; van der Laan, G.; Wang, W. W.; Haghighirad, A. A.; Hesjedal, T.

2018-06-01

Magnetic skyrmions in noncentrosymmetric helimagnets with Dn symmetry are Bloch-type magnetization swirls with a helicity angle of ±9 0 ° . At the surface of helimagnetic thin films below a critical thickness, a twisted skyrmion state with an arbitrary helicity angle has been proposed; however, its direct experimental observation has remained elusive. Here, we show that circularly polarized resonant elastic x-ray scattering is able to unambiguously measure the helicity angle of surface skyrmions, providing direct experimental evidence that a twisted skyrmion surface state also exists in bulk systems. The exact surface helicity angles of twisted skyrmions for both left- and right-handed chiral bulk Cu2 OSeO3 , in the single as well as in the multidomain skyrmion lattice state, are determined, revealing their detailed internal structure. Our findings suggest that a skyrmion surface reconstruction is a universal phenomenon, stemming from the breaking of translational symmetry at the interface.

MoManI: a tool to facilitate research, analysis, and teaching of computer models

NASA Astrophysics Data System (ADS)

Howells, Mark; Pelakauskas, Martynas; Almulla, Youssef; Tkaczyk, Alan H.; Zepeda, Eduardo

2017-04-01

Allocating limited resource efficiently is a task to which efficient planning and policy design aspires. This may be a non-trivial task. For example, the seventh sustainable development goal (SDG) of Agenda 2030 is to provide access to affordable sustainable energy to all. On the one hand, energy is required to realise almost all other SDGs. (A clinic requires electricity for fridges to store vaccines for maternal health, irrigate agriculture requires energy to pump water to crops in dry periods etc.) On the other hand, the energy system is non-trivial. It requires the mapping of resource, its conversion into useable energy and then into machines that we use to meet our needs. That requires new tools that draw from standard techniques, best-in-class models and allow the analyst to develop new models. Thus we present the Model Management Infrastructure (MoManI). MoManI is used to develop, manage, run, store input and results data for linear programming models. MoManI, is a browser-based open source interface for systems modelling. It is available to various user audiences, from policy makers and planners through to academics. For example, we implement the Open Source energy Modelling System (OSeMOSYS) in MoManI. OSeMOSYS is a specialized energy model generator. A typical OSeMOSYS model would represent the current energy system of a country, region or city; in it, equations and constraints are specified; and calibrated to a base year. From that future technologies and policy options are represented. From those scenarios are designed and run. Efficient allocation of energy resource and expenditure on technology is calculated. Finally, results are visualized. At present this is done in relatively rigid interfaces or via (for some) cumbersome text files. Implementing and operating OSeMOSYS in MoManI shortens the learning curve and reduces phobia associated with the complexity of computer modelling, thereby supporting effective capacity building activities. The novel structure of MoManI allows different teams to collaborate simultaneously from around the globe. Each user can easily edit and update any part of the modelling process: from the underlying mathematical equations of OSeMOSYS through to the visualization of results. Going forward, this tools' flexible structure will make it a potential interface for a larger selection of modelling tools, thus extending its use from OSeMOSYS for energy to other systems modelling, moving beyond SDG7 to others.

Open system environment procurement

NASA Technical Reports Server (NTRS)

Fisher, Gary

1994-01-01

Relationships between the request for procurement (RFP) process and open system environment (OSE) standards are described. A guide was prepared to help Federal agency personnel overcome problems in writing an adequate statement of work and developing realistic evaluation criteria when transitioning to an OSE. The guide contains appropriate decision points and transition strategies for developing applications that are affordable, scalable and interoperable across a broad range of computing environments. While useful, the guide does not eliminate the requirement that agencies posses in-depth expertise in software development, communications, and database technology in order to evaluate open systems.

Study of surfaces using near infrared optical fiber spectrometry

NASA Technical Reports Server (NTRS)

Workman, G. L.; Arendale, W. A.; Hughes, C.

1995-01-01

The measurement and control of cleanliness for critical surfaces during manufacturing and in service provides a unique challenge for fulfillment of environmentally benign operations. Of particular interest has been work performed in maintaining quality in the production of bondline surfaces in propulsion systems and the identification of possible contaminants. This work requires an in-depth study of the possible sources of contamination, methodologies to identify contaminants, discrimination between contaminants and chemical species caused by environment, and the effect of particular contaminants on the bondline integrity of the critical surfaces. This presentation will provide an introduction to the use of optical fiber spectrometry in a nondestructive measurement system for process monitoring and how it can be used to help clarify issues concerning surface chemistry. Correlation of the Near Infrared (NIR) spectroscopic results with Optical Stimulated Electron Emission (OSEE) and ellipsometry will also be presented.

Function of Platelet-Induced Epithelial Attachment at Titanium Surfaces Inhibits Microbial Colonization.

PubMed

Maeno, M; Lee, C; Kim, D M; Da Silva, J; Nagai, S; Sugawara, S; Nara, Y; Kihara, H; Nagai, M

2017-06-01

The aim of this study was to evaluate the barrier function of platelet-induced epithelial sheets on titanium surfaces. The lack of functional peri-implant epithelial sealing with basal lamina (BL) attachment at the interface of the implant and the adjacent epithelium allows for bacterial invasion, which may lead to peri-implantitis. Although various approaches have been reported to combat bacterial infection by surface modifications to titanium, none of these have been successful in a clinical application. In our previous study, surface modification with protease-activated receptor 4-activating peptide (PAR4-AP), which induced platelet activation and aggregation, was successful in demonstrating epithelial attachment via BL and epithelial sheet formation on the titanium surface. We hypothesized that the platelet-induced epithelial sheet on PAR4-AP-modified titanium surfaces would reduce bacterial attachment, penetration, and invasion. Titanium surface was modified with PAR4-AP and incubated with platelet-rich plasma (PRP). The aggregated platelets released collagen IV, a critical BL component, onto the PAR4-AP-modified titanium surface. Then, human gingival epithelial cells were seeded on the modified titanium surface and formed epithelial sheets. Green fluorescent protein (GFP)-expressing Escherichia coli was cultured onto PAR4-AP-modified titanium with and without epithelial sheet formation. While Escherichia coli accumulated densely onto the PAR4-AP titanium lacking epithelial sheet, few Escherichia coli were observed on the epithelial sheet on the PAR4-AP surface. No bacterial invasion into the interface of the epithelial sheet and the titanium surface was observed. These in vitro results indicate the efficacy of a platelet-induced epithelial barrier that functions to prevent bacterial attachment, penetration, and invasion on PAR4-AP-modified titanium.

A trans-acting enhancer modulates estrogen-mediated transcription of reporter genes in osteoblasts.

PubMed

Sasaki-Iwaoka, H; Maruyama, K; Endoh, H; Komori, T; Kato, S; Kawashima, H

1999-02-01

The presence of bone-specific estrogen agonists and discovery of the osteoblast-specific transcription factor (TF), Cbfa1, together with the discovery of synergism between a TF Pit-1 and estrogen receptor alpha (ERalpha) on rat prolactin gene, led to investigation of Cbfa1 in the modulation of osteoblast-specific actions of estrogen. Reverse transcribed-polymerase chain reaction demonstrated expression of Cbfa1 in the osteoblastic cell lines, MG63, ROS17/2.8, and MC3T3E1, but not in nonosteoblastic cell lines, MCF7, C3H10T1/2, and HeLa. An ER expression vector and a series of luciferase (Luc) reporter plasmids harboring the Cbfa1 binding site OSE2 (the osteoblast-specific cis element in the osteocalcin promoter) and palindromic estrogen response elements (EREs) were cotransfected into both osteoblastic and nonosteoblastic cells. OSE2 worked as a cis- acting element in osteoblastic cells but not nonosteoblastic cells, whereas EREs were cis- acting in all cell lines. Synergistic transactivation was observed in osteoblastic cells only when both ERE and OSE2 were placed in juxtaposition to the promoter. Forced expression of Cbfa1 in C3H10T1/2 cells also induced synergism. Tamoxifen, a partial agonist/antagonist of estrogen, acted as an osteoblast-specific agonist in cells transfected with a promoter containing ERE and acted synergistically with a promoter containing the ERE-OSE2 enhancer combination. These results support the idea that bone-specific TFs modulate the actions of estrogen in a tissue-specific manner.

Satisfactory arterial repair 1 year after ultrathin strut biodegradable polymer sirolimus-eluting stent implantation: an angioscopic observation.

PubMed

Ishihara, Takayuki; Awata, Masaki; Iida, Osamu; Fujita, Masashi; Masuda, Masaharu; Okamoto, Shin; Nanto, Kiyonori; Kanda, Takashi; Tsujimura, Takuya; Uematsu, Masaaki; Mano, Toshiaki

2018-01-15

The ultrathin strut biodegradable polymer sirolimus-eluting stent (Orsiro, O-SES) exhibits satisfactory clinical outcomes. However, no report to date has documented the intravascular status of artery repair after O-SES implantation. We examined 5 O-SES placed in 4 patients (age 65 ± 12 years, male 75%) presenting with stable angina pectoris due to de novo lesions in native coronary arteries. Coronary angioscopy was performed immediately after percutaneous coronary intervention and 1 year later. Angioscopic images were analyzed to determine the following: (1) dominant grade of neointimal coverage (NIC) over the stent; (2) maximum yellow plaque grade; and (3) existence of thrombus. Yellow plaque grade was evaluated both immediately after stent implantation and at the time of follow-up observation. The other parameters were evaluated at the time of follow-up examination. NIC was graded as: grade 0, stent struts exposed; grade 1, struts bulging into the lumen, although covered; grade 2, struts embedded in the neointima, but translucent; grade 3, struts fully embedded and invisible. Yellow plaque severity was graded as: grade 0, white; grade 1, light yellow; grade 2, yellow; and grade 3, intensive yellow. Angioscopic findings at 1 year demonstrated the following: dominant NIC grade 1, grade 2, and grade 3 in 1, 2, and 2 stents, respectively; all stents were covered to some extent; focal thrombus adhesion was observed in only 1 stent. Yellow plaque grade did not change from immediately after stent implantation to follow-up. O-SES demonstrated satisfactory arterial repair 1 year after implantation.

Development and application of contamination technology for MSFC managed space systems

NASA Technical Reports Server (NTRS)

1993-01-01

The second annual report on the development and application of contamination technology for MSFC managed space systems covering the period from 10 Dec. 1992 to 10 Dec. 1993 is presented. During this time period, studies were concluded which proved that in-process corrosion protection is not required during Redesigned Solid Rocket Motor (RSRM) case processing. Also completed were a series of tests evaluating the effects of environmental exposure and contamination on 2219-T87 aluminum (Space Shuttle External Tank) OSEE response and bonding properties. Correlations were developed between OSEE response, contamination type/level, and primer adhesion. The results showed that the wet tape and water break free tests currently employed during ET processing may not detect bond affecting levels of some potential contaminants; however, the contaminants were detected with OSEE analysis. Finally, exposure/contamination studies were initiated with HP9-4-30 steel. HP9-4-30 was selected for evaluation because it represents a class of metals commom to MSFC managed space flight systems which are less prone to oxidation than D6AC steel or aluminum.

Development and application of contamination technology for MSFC managed space systems

NASA Astrophysics Data System (ADS)

The second annual report on the development and application of contamination technology for MSFC managed space systems covering the period from 10 Dec. 1992 to 10 Dec. 1993 is presented. During this time period, studies were concluded which proved that in-process corrosion protection is not required during Redesigned Solid Rocket Motor (RSRM) case processing. Also completed were a series of tests evaluating the effects of environmental exposure and contamination on 2219-T87 aluminum (Space Shuttle External Tank) OSEE response and bonding properties. Correlations were developed between OSEE response, contamination type/level, and primer adhesion. The results showed that the wet tape and water break free tests currently employed during ET processing may not detect bond affecting levels of some potential contaminants; however, the contaminants were detected with OSEE analysis. Finally, exposure/contamination studies were initiated with HP9-4-30 steel. HP9-4-30 was selected for evaluation because it represents a class of metals commom to MSFC managed space flight systems which are less prone to oxidation than D6AC steel or aluminum.

Dielectric and phonon properties of the multiferroic ferrimagnet Cu{sub 2}OSeO{sub 3}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Apostolova, I. N., E-mail: inaapos@abv.bg

2014-02-14

We propose a microscopic model in order to study the multiferroic properties of Cu{sub 2}OSeO{sub 3} taking into account the ferrimagnetic interaction, frustration, linear magnetoelectric (ME) coupling, and anharmonic spin-phonon interaction. We have shown that the dielectric constant and the phonon energy and damping have a kink near the magnetic phase transition T{sub C} = 58 K which disappears with increasing of an external magnetic field. This behavior is an evidence for a strong ME coupling and in qualitative agreement with the experimental data.

Microwave Magnetochiral Dichroism in the Chiral-Lattice Magnet Cu2OSeO3

NASA Astrophysics Data System (ADS)

Okamura, Y.; Kagawa, F.; Seki, S.; Kubota, M.; Kawasaki, M.; Tokura, Y.

2015-05-01

Through broadband microwave spectroscopy in Faraday geometry, we observe distinct absorption spectra accompanying magnetoelectric (ME) resonance for oppositely propagating microwaves, i.e., directional dichroism, in the multiferroic chiral-lattice magnet Cu2OSeO3. The magnitude of the directional dichroism critically depends on the magnetic-field direction. Such behavior is well accounted for by considering the relative direction of the oscillating electric polarizations induced via the ME effect with respect to microwave electric fields. Directional dichroism in a system with an arbitrary form of ME coupling can be also discussed in the same manner.

Establishment of Epithelial Attachment on Titanium Surface Coated with Platelet Activating Peptide

PubMed Central

Sugawara, Shiho; Maeno, Masahiko; Lee, Cliff; Nagai, Shigemi; Kim, David M.; Da Silva, John; Kondo, Hisatomo

2016-01-01

The aim of this study was to produce epithelial attachment on a typical implant abutment surface of smooth titanium. A challenging complication that hinders the success of dental implants is peri-implantitis. A common cause of peri-implantitis may results from the lack of epithelial sealing at the peri-implant collar. Histologically, epithelial sealing is recognized as the attachment of the basement membrane (BM). BM-attachment is promoted by activated platelet aggregates at surgical wound sites. On the other hand, platelets did not aggregate on smooth titanium, the surface typical of the implant abutment. We then hypothesized that epithelial BM-attachment was produced when titanium surface was modified to allow platelet aggregation. Titanium surfaces were coated with a protease activated receptor 4-activating peptide (PAR4-AP). PAR4-AP coating yielded rapid aggregation of platelets on the titanium surface. Platelet aggregates released robust amount of epithelial chemoattractants (IGF-I, TGF-β) and growth factors (EGF, VEGF) on the titanium surface. Human gingival epithelial cells, when they were co-cultured on the platelet aggregates, successfully attached to the PAR4-AP coated titanium surface with spread laminin5 positive BM and consecutive staining of the epithelial tight junction component ZO1, indicating the formation of complete epithelial sheet. These in-vitro results indicate the establishment of epithelial BM-attachment to the titanium surface. PMID:27741287

The Downward Continuation to the Earth’s Surface of Truncated Spherical and Ellipsoidal Harmonic Series of the Gravity and Height Anomalies,

DTIC Science & Technology

1981-12-01

triangle OBQ, we obtain r c =COtI ose + sine (411) Hence with (4.10) e 2 sinecose (412)tan ip = (__o__2)_ 1 - e 2sin2 0 Pythagoras ’ theorem then easily...coordinate system. Strictly, this theorem tinds no application in our physical world since it guarantees convergence only outside the sphere enclosing...Junq, 1956, p.54 3 ; Moritz, 1980, p.52) is found, using the above theorem , to be f =E, the focal distance of the ellipsoid, shoving also that the

Belinostat in Treating Patients With Advanced Ovarian Epithelial Cancer, Primary Peritoneal Cancer, or Fallopian Tube Cancer or Ovarian Low Malignant Potential Tumors

ClinicalTrials.gov

2016-10-20

Fallopian Tube Carcinoma; Primary Peritoneal Carcinoma; Recurrent Borderline Ovarian Surface Epithelial-Stromal Tumor; Recurrent Ovarian Carcinoma; Stage III Borderline Ovarian Surface Epithelial-Stromal Tumor; Stage III Ovarian Cancer; Stage IV Borderline Ovarian Surface Epithelial-Stromal Tumor; Stage IV Ovarian Cancer

Using Optically Stimulated Electron Emission as an Inspection Method to Monitor Surface Contamination

NASA Technical Reports Server (NTRS)

Lingbloom, Mike S.

2008-01-01

During redesign of the Space Shuttle reusable solid rocket motor (RSRM), NASA amended the contract with ATK Launch Systems (then Morton Thiokol Inc.) with Change Order 966 to implement a contamination control and cleanliness verification method. The change order required: (1) A quantitative inspection method (2) A written record of actual contamination levels versus a known reject level (3) A method that is more sensitive than existing methods of visual and black light inspection. Black light inspection is only useful for inspection of contaminants that fluoresce near the 365 nm spectral line and is not useful for inspection of most silicones that will not produce strong fluorescence. Black light inspection conducted by a qualified inspector under controlled light is capable of detecting Conoco HD-2 grease in gross amounts and is very subjective due to operator sensitivity. Optically stimulated electron emission (OSEE), developed at the Materials and Process Laboratory at Marshall Space Flight Center (MSFC), was selected to satisfy Change Order 966. OSEE offers several important advantages over existing laboratory methods with similar sensitivity, e.g., spectroscopy and nonvolatile residue sampling, which provide turn around time, real time capability, and full coverage inspection capability. Laboratory methods require sample gathering and in-lab analysis, which sometimes takes several days to get results. This is not practical in a production environment. In addition, these methods do not offer full coverage inspection of the large components

Advancements in OSeMOSYS - the Open Source energy MOdelling SYStem

NASA Astrophysics Data System (ADS)

Gardumi, Francesco; Almulla, Youssef; Shivakumar, Abhishek; Taliotis, Constantinos; Howells, Mark

2017-04-01

This work provides a review of the latest developments and applications of OSeMOSYS energy systems model generator. OSeMOSYS was launched at Oxford university in 2011, including co-authors from UCL, UNIDO, UCT, Stanford, PSI and other institutions. It was designed to fill a gap in the energy modelling toolkit, where no open source optimising model generators were available at the time. OSeMOSYS is free, open source and accessible. Written in GNU MathProg programming language, it can generate from small village energy models up to global multi-resource integrated - Climate, Land, Energy, Water - models. In its most widespread version it calculates what investments to make, when, at what capacity and how to operate them, to meet given final demands and policy targets at the lowest cost. OSeMOSYS is structured into blocks of functionalities, each consisting in a stand-alone set of equations which can be plugged into the core code to add specific insights for the case-study of interest. Originally, seven blocks of functionalities for the objective function, costs, storage, capacity adequacy, energy balance, constraints, emissions were provided, documented by plain English descriptions and algebraic formulations. Recently, the block for storage was deeply revised and developed, while new blocks of functionality for studying short-term implications of energy planning onto the electricity system were designed. These include equations for computing 1) the reserve capacity dispatch; 2) the costs of flexible operation of power plants and 3) the reserve capacity demand as a function of the penetration of intermittent renewables were introduced. Additionally, a revision of the whole code was completed, as the result of a public call launched and led by UNite Ideas. This allowed the computational time to be greatly reduced and opened up the path to refinements of the scales of analysis. Finally, the code was made available in Python and GAMS programming languages, thus engaging two of the widest existing communities of programmers. Such developments allowed a number of applications to be produced at different scales. Regional and country models were generated for the whole of South America and Sub-Saharan Africa. A Pan-European model is under development. Models of Cyprus and Tunisia, detailed down to the individual power plant, are among the latest applications. Finally, integrated assessment water-energy models have been generated for regions in Central Asia and the Balkans, in the framework of the UNECE Water Convention. These look into trans-boundary issues related to the water and energy management along river basins, including detailed representations of water storage and cascading power plants. This multiplicity of developments and applications of OSeMOSYS engages a wide community of users and decision-makers and fosters the use of modelling tools for energy planning. This fulfils a scientific and social mission to empower communities with the development of solutions for a better access to energy.

Oxidation of dimethylselenide by δMnO2: oxidation product and factors affecting oxidation rate

USGS Publications Warehouse

Wang, Bronwen; Burau, Richard G.

1995-01-01

Volatile dimethylselenide (DMSe) was transformed to a nonvolatile Se compound in a ??-MnO2 suspension. The nonvolatile product was a single compound identified as dimethylselenoxide based on its mass spectra pattern. After 24 h, 100% of the DMSe added to a ??-MnO2 suspension was converted to nonpurgable Se as opposed to 20%, 18%, and 4% conversion for chromate, permanganate, and the filtrate from the suspension, respectively. Manganese was found in solution after reaction. These results imply that the reaction between manganese oxide and DMSe was a heterogeneous redox reaction involving solid phase ??-MnO2 and solution phase DMSe. Oxidation of DMSe to dimethylselenoxide [OSe(CH3)2] by a ??-MnO2 suspension appears to be first order with respect to ??-MnO2, to DMSe, and to hydrogen ion with an overall rate law of d[OSe(CH3)2 ]/dt = 95 M-2 min-1 [MnO2]1[DMSe]1[H+]1 for the MnO2 concentration range of 0.89 ?? 10-3 - 2.46 ?? 10-3 M, the DMSe concentration range of 3.9 ?? 10-7 - 15.5 ?? 10-7 M Se, and a hydrogen ion concentation range of 7.4 ?? 10-6 -9.5 ?? 10-8 M. A general surface site adsorption model is consistent with this rate equation if the uncharged |OMnOH is the surface adsorption site. DMSe acts as a Lewis base, and the manganese oxide surface acts as a Lewis acid. DMSe adsorption to |OMnOH can be viewed as a Lewis acid/ base complex between the largely p orbitals of the DMSe lone pair and the unoccupied eg orbitals on manganese oxide. For such a complex, frontier molecular orbital theory predicts electron transfer to occur via an inner-sphere complex between the DMSe and the manganese oxide. ?? 1995 American Chemical Society.

Crystal structure of 1,2,3,5-di-O-methyl­ene-α-d-xylo­furan­ose

PubMed Central

Tiritiris, Ioannis; Tussetschläger, Stefan; Kantlehner, Willi

2015-01-01

The title compound, C7H10O5, was synthesized by reaction of d-xylose with paraformaldehyde. In the crystal, the central part of the mol­ecule consists of a five-membered C4O ring with an envelope conformation, with the methine C atom adjacent to the O atom being the flap. The protected O atoms of both cyclic acetal groups are oriented so that the four chiral C atoms of the furan­ose part show an R configuration. C—H⋯O hydrogen bonds are present between adjacent mol­ecules, generating a three-dimensional network. PMID:26594582

Crystal structure of 1,2,3,4-di-O-methyl­ene-α-d-galacto­pyran­ose

PubMed Central

Tiritiris, Ioannis; Tussetschläger, Stefan; Kantlehner, Willi

2015-01-01

The title compound, C8H12O6, was synthesized by de­acetyl­ation of 6-acetyl-1,2,3,4-di-O-methyl­ene-α-d-galactose with sodium methoxide. The central part of the mol­ecule consists of a six-membered C5O pyran­ose ring with a twist-boat conformation. Both fused dioxolane rings adopt an envelope conformation with C and O atoms as the flap. In the crystal, O—H⋯O and C—H⋯O hydrogen bonds are present between adjacent mol­ecules, generating a three-dimensional network. PMID:26870551

Phase diagram and magnetic relaxation phenomena in Cu2OSeO3

NASA Astrophysics Data System (ADS)

Qian, F.; Wilhelm, H.; Aqeel, A.; Palstra, T. T. M.; Lefering, A. J. E.; Brück, E. H.; Pappas, C.

2016-08-01

We present an investigation of the magnetic-field-temperature phase diagram of Cu2OSeO3 based on dc magnetization and ac susceptibility measurements covering a broad frequency range of four orders of magnitude, from very low frequencies reaching 0.1 Hz up to 1 kHz. The experiments were performed in the vicinity of Tc=58.2 K and around the skyrmion lattice A phase. At the borders between the different phases the characteristic relaxation times reach several milliseconds and the relaxation is nonexponential. Consequently the borders between the different phases depend on the specific criteria and frequency used and an unambiguous determination is not possible.

Direct observation of attractive skyrmions and skyrmion clusters in the cubic helimagnet Cu2OSeO3

NASA Astrophysics Data System (ADS)

Loudon, J. C.; Leonov, A. O.; Bogdanov, A. N.; Hatnean, M. Ciomaga; Balakrishnan, G.

2018-04-01

We report the discovery of attractive magnetic skyrmions and their clusters in noncentrosymmetric ferromagnets. These three-dimensional solitons have been predicted to exist in the cone phase of chiral ferromagnets [J. Phys: Condens. Matter 28, 35LT01 (2016), 10.1088/0953-8984/28/35/35LT01] and are fundamentally different from the more common repulsive axisymmetric skyrmions that occur in the magnetically saturated state. We present real-space images of these skyrmion clusters in thin (˜70 nm) single-crystal samples of Cu2OSeO3 taken using transmission electron microscopy and develop a phenomenological theory describing this type of skyrmion.

Malondialdehyde epitopes as targets of immunity and the implications for atherosclerosis

PubMed Central

Binder, Christoph J.

2018-01-01

Accumulating evidence suggests that oxidation-specific epitopes (OSEs) constitute a novel class of damage-associated molecular patterns (DAMPs) generated during high oxidative stress but also in the physiological process of apoptosis. To deal with the potentially harmful consequences of such epitopes, the immune system has developed several mechanisms to protect from OSEs and to orchestrate their clearance, including IgM natural antibodies and both cellular and membrane-bound receptors. Here, we focus on malondialdehyde (MDA) epitopes as prominent examples of OSEs that trigger both innate and adaptive immune responses. First, we review the mechanism of MDA generation, the different types of adducts on various biomolecules and provide relevant examples for physiological carriers of MDA such as apoptotic cells, microvesicles (MV) or oxidized low-density lipoproteins (LDL). Based on recent insights, we argue that MDA epitopes contribute to the maintenance of homeostatic functions by acting as markers of elevated oxidative stress and tissue damage. We discuss multiple lines of evidence that MDA epitopes are pro-inflammatory and thus important targets of innate and adaptive immune responses. Finally, we illustrate the relevance of MDA epitopes in human pathologies by describing their capacity to drive inflammatory processes in atherosclerosis and highlighting protective mechanisms of immunity that could be exploited for therapeutic purposes. PMID:27235680

Spin-Hall magnetoresistance in multidomain helical spiral systems

NASA Astrophysics Data System (ADS)

Aqeel, A.; Mostovoy, M.; van Wees, B. J.; Palstra, T. T. M.

2017-05-01

We study the spin-Hall magnetoresistance (SMR) in multidomain helical spiral magnet Cu2OSeO{{}3}| Pt heterostructures. We compare the SMR response of Cu2OSeO3 at 5 K, when the magnetic domains are almost frozen, to that at elevated temperatures, when domain walls move easily. At 5 K the SMR amplitude vanishes at low applied magnetic fields, while at 50 K it does not. This phenomenon can be explained by the effect of the magnetic field on the domain structure of Cu2OSeO3. At elevated temperatures the system can reach the thermodynamic equilibrium state, in which a single domain that has a minimal energy for a given field direction occupies the whole sample and gives rise to a nonzero SMR signal. In contrast at 5 K, the three types of domains with mutually orthogonal spiral wave vectors have equal volumes independent of the field direction, which leads to the cancellation of the SMR signal at low fields. In the single-domain conical spiral and collinear ferrimagnetic states, the angular and field dependence of the SMR is found to be same at all temperatures (T≤slant 50 K). This behavior can be understood within the framework of the SMR theory developed for collinear magnets.

Gravity affects the responsiveness of Runx2 to 1, 25-dihydroxyvitamin D3 (VD3)

NASA Astrophysics Data System (ADS)

Guo, Feima; Dai, Zhongquan; Wu, Feng; Liu, Zhaoxia; Tan, Yingjun; Wan, Yumin; Shang, Peng; Li, Yinghui

2013-03-01

Bone loss resulting from spaceflight is mainly caused by decreased bone formation, and decreased osteoblast proliferation and differentiation. Transcription factor Runx2 plays an important role in osteoblast differentiation and function by responding to microenvironment changes including cytokine and mechanical factors. The effects of 1, 25-dihydroxyvitamin D3 (VD3) on Runx2 in terms of mechanical competence is far less clear. This study describes how gravity affects the response of Runx2 to VD3. A MC3T3-6OSE2-Luc osteoblast model was constructed in which the activity of Runx2 was reflected by reporter luciferase activity identifed by bone-related cytokines. The results showed that luciferase activity in MC3T3-6OSE2-Luc cells transfected with Runx2 was twice that of the vacant vector. Alkaline phosphatase (ALP) activity was increased in MC3T3-6OSE2-Luc cells by different concentrations of IGF-I and BMP2. MC3T3-6OSE2-Luc cells were cultured under simulated microgravity or centrifuge with or without VD3. In simulated microgravity, luciferase activity was decreased after 48 h of clinorotation culture, but increased in the centrifuge culture. Luciferase activity was increased after VD3 treatment in normal conditions and simulated microgravity, the increase in luciferase activity in simulated microgravity was lower than that in the 1 g condition when simultaneously treated with VD3 and higher than that in the centrifuge condition. Co-immunoprecipitation showed that the interaction between the VD3 receptor (VDR) and Runx2 was decreased by simulated microgravity, but increased by centrifugation. From these results, we conclude that gravity affects the response of Runx2 to VD3 which results from an alteration in the interaction between VDR and Runx2 under different gravity conditions.

Electric field control of the skyrmion lattice in Cu2OSeO3

NASA Astrophysics Data System (ADS)

White, J. S.; Levatić, I.; Omrani, A. A.; Egetenmeyer, N.; Prša, K.; Živković, I.; Gavilano, J. L.; Kohlbrecher, J.; Bartkowiak, M.; Berger, H.; Rønnow, H. M.

2012-10-01

Small-angle neutron scattering has been employed to study the influence of applied electric (E-)fields on the skyrmion lattice in the chiral lattice magnetoelectric Cu2OSeO3. Using an experimental geometry with the E-field parallel to the [111] axis, and the magnetic field parallel to the [1\\bar {1}0] axis, we demonstrate that the effect of applying an E-field is to controllably rotate the skyrmion lattice around the magnetic field axis. Our results are an important first demonstration for a microscopic coupling between applied E-fields and the skyrmions in an insulator, and show that the general emergent properties of skyrmions may be tailored according to the properties of the host system.

Quantification of Acute Vocal Fold Epithelial Surface Damage with Increasing Time and Magnitude Doses of Vibration Exposure

PubMed Central

Kojima, Tsuyoshi; Van Deusen, Mark; Jerome, W. Gray; Garrett, C. Gaelyn; Sivasankar, M. Preeti; Novaleski, Carolyn K.; Rousseau, Bernard

2014-01-01

Because the vocal folds undergo repeated trauma during continuous cycles of vibration, the epithelium is routinely susceptible to damage during phonation. Excessive and prolonged vibration exposure is considered a significant predisposing factor in the development of vocal fold pathology. The purpose of the present study was to quantify the extent of epithelial surface damage following increased time and magnitude doses of vibration exposure using an in vivo rabbit phonation model. Forty-five New Zealand white breeder rabbits were randomized to nine groups and received varying phonation time-doses (30, 60, or 120 minutes) and magnitude-doses (control, modal intensity phonation, or raised intensity phonation) of vibration exposure. Scanning electron microscopy and transmission electron microscopy was used to quantify the degree of epithelial surface damage. Results revealed a significant reduction in microprojection density, microprojection height, and depth of the epithelial surface with increasing time and phonation magnitudes doses, signifying increased epithelial surface damage risk with excessive and prolonged vibration exposure. Destruction to the epithelial cell surface may provide significant insight into the disruption of cell function following prolonged vibration exposure. One important goal achieved in the present study was the quantification of epithelial surface damage using objective imaging criteria. These data provide an important foundation for future studies of long-term tissue recovery from excessive and prolonged vibration exposure. PMID:24626217

Gene expression of matrix metalloproteinases and LH receptors in mare follicular development.

PubMed

Bastos, H B A; Kretzmann, N A; Santos, G O; Esmeraldino, A T; Rechsteiner, S Fiala; Mattos, R C; Neves, A P

2014-11-01

The period from the emergence of a dominant follicle until its formation requires tissue remodeling. Enzymes promoting collagen lysis, such as matrix metalloproteinases (MMPs), are fundamental for the process of extracellular matrix remodeling, which allows changes in ovarian tissue architecture during follicular growth. It has been suggested that the production of these enzymes may be affected by the rise in circulating concentrations of LH, which acts on the ovarian surface epithelium (OSE). The aim of this study was to determine the expression of MMP-1, MMP-2, and LH receptor (LHR) in the ovulation fossa and in the central portion of the equine ovary during follicular deviation and dominance. Ovaries of 12 cyclic mares were selected and subsequently divided into two groups: development (DEV) group and dominant (DOM) group. The DEV group consisted of ovaries from six animals whose follicles were less than 28 mm in diameter (follicular deviation), and the DOM group consisted of ovaries from six animals whose follicles measured 28 mm or more in diameter (dominant follicles). The latter group was divided into two subgroups: the group of ovaries with a dominant follicle (DOM-D) and the group of contralateral ovaries (DOM-C). Our results showed that mRNA for MMP-1, MMP-2, and LHR was present in the equine ovary during follicle development, in the ovulation fossa, and in the central portion of the ovary. MMP-1 and LHR gene expression was greater (P < 0.05) for the DOM-D group compared with the DOM-C group. In the DOM-D group, MMP-1, MMP-2, and LHR gene expression was greater (P < 0.05) in the ovarian stroma compared with the ovulation fossa. Using immunohistochemistry, OSE from the DOM group showed increased expression compared with the DEV group (P < 0.05). In conclusion, we demonstrated that MMP-1 and MMP-2 might be fundamental for events related to tissue remodeling, which occurs during follicular development until the formation of the dominant follicle. We also demonstrated the relationship between the gene expression of MMPs and the gene and protein expression of LHR, suggesting that LHR in the OSE might be an important factor to initiate the signaling cascade that culminates with the production of MMPs. Copyright © 2014 Elsevier Inc. All rights reserved.

Stimulation of ovarian stem cells by follicle stimulating hormone and basic fibroblast growth factor during cortical tissue culture.

PubMed

Parte, Seema; Bhartiya, Deepa; Manjramkar, Dhananjay D; Chauhan, Anahita; Joshi, Amita

2013-04-01

Cryopreserved ovarian cortical tissue acts as a source of primordial follicles (PF) which can either be auto-transplanted or cultured in vitro to obtain mature oocytes. This offers a good opportunity to attain biological parenthood to individuals with gonadal insufficiency including cancer survivors. However, role of various intra- and extra-ovarian factors during PF growth initiation still remain poorly understood. Ovarian biology has assumed a different dimension due to emerging data on presence of pluripotent very small embryonic-like stem cells (VSELs) and ovarian germ stem cells (OGSCs) in ovary surface epithelium (OSE) and the concept of postnatal oogenesis. The present study was undertaken to decipher effect of follicle stimulating hormone (FSH) and basic fibroblast growth factor (bFGF) on the growth initiation of PF during organ culture with a focus on ovarian stem cells. Serum-free cultures of marmoset (n=3) and human (young and peri-menopausal) ovarian cortical tissue pieces were established. Cortical tissue pieces stimulated with FSH (0.5 IU/ml) or bFGF (100 ng/ml) were collected on Day 3 for histological and molecular studies. Gene transcripts specific for pluripotency (Oct-4A, Nanog), early germ cells (Oct-4, c-Kit, Vasa) and to reflect PF growth initiation (oocyte-specific Gdf-9 and Lhx8, and granulosa cells specific Amh) were studied by q-RTPCR. A prominent proliferation of OSE (which harbors stem cells) and transition of PF to primary follicles was observed after FSH and bFGF treatment. Ovarian stem cells were found to be released on the culture inserts and retained the potential to spontaneously differentiate into oocyte-like structures in extended cultures. q-RTPCR analysis revealed an increased expression of gene transcripts specific for VSELs, OGSCs and early germ cells suggestive of follicular transition. The present study shows that both FSH and bFGF stimulate stem cells present in OSE and also lead to PF growth initiation. Thus besides being a source of PF, cryopreserved ovarian cortical tissue could also be a source of stem cells which retain the ability to spontaneously differentiate into oocyte-like structures in vitro. Results provide a paradigm shift in the basic understanding of FSH action and also offer a new perspective to the field of oncofertility research.

Examination of Observation Impacts derived from OSEs and Adjoint Models

NASA Technical Reports Server (NTRS)

Gelaro, Ronald

2008-01-01

With the adjoint of a data assimilation system, the impact of any or all assimilated observations on measures of forecast skill can be estimated accurately and efficiently. The approach allows aggregation of results in terms of individual data types, channels or locations, all computed simultaneously. In this study, adjoint-based estimates of observation impact are compared with results from standard observing system experiments (OSEs) in the NASA Goddard Earth Observing System Model, Version 5 (GEOS-5) GEOS-5 system. The two approaches are shown to provide unique, but complimentary, information. Used together, they reveal both redundancies and dependencies between observing system impacts as observations are added or removed. Understanding these dependencies poses a major challenge for optimizing the use of the current observational network and defining requirements for future observing systems.

Differential effects of aging and exercise on intra-abdominal adipose arteriolar function and blood flow regulation

PubMed Central

Davis, Robert T.; Stabley, John N.; Dominguez, James M.; Ramsey, Michael W.; McCullough, Danielle J.; Lesniewski, Lisa A.; Delp, Michael D.

2013-01-01

Adipose tissue (AT), which typically comprises an increased percentage of body mass with advancing age, receives a large proportion of resting cardiac output. During exercise, an old age-associated inability to increase vascular resistance within the intra-abdominal AT may compromise the ability of the cardiovascular system to redistribute blood flow to the active musculature, contributing to the decline in exercise capacity observed in this population. We tested the hypotheses that 1) there would be an elevated perfusion of AT during exercise with old age that was associated with diminished vasoconstrictor responses of adipose-resistance arteries, and 2) chronic exercise training would mitigate the age-associated alterations in AT blood flow and vascular function. Young (6 mo; n = 40) and old (24 mo; n = 28) male Fischer 344 rats were divided into young sedentary (YSed), old sedentary (OSed), young exercise trained (YET), or old exercise trained (OET) groups, where training consisted of 10-12 wk of treadmill exercise. In vivo blood flow at rest and during exercise and in vitro α-adrenergic and myogenic vasoconstrictor responses in resistance arteries from AT were measured in all groups. In response to exercise, there was a directionally opposite change in AT blood flow in the OSed group (∼150% increase) and YSed (∼55% decrease) vs. resting values. Both α-adrenergic and myogenic vasoconstriction were diminished in OSed vs. YSed AT-resistance arteries. Exercise training resulted in a similar AT hyperemic response between age groups during exercise (YET, 9.9 ± 0.5 ml·min−1·100−1 g; OET, 8.1 ± 0.9 ml·min−1·100−1 g) and was associated with enhanced myogenic and α-adrenergic vasoconstriction of AT-resistance arteries from the OET group relative to OSed. These results indicate that there is an inability to increase vascular resistance in AT during exercise with old age, due, in part, to a diminished vasoconstriction of AT arteries. Furthermore, the results indicate that exercise training can augment vasoconstriction of AT arteries and mitigate age-related alterations in the regulation of AT blood flow during exercise. PMID:23349454

Withaferin A (WFA) inhibits tumor growth and metastasis by targeting ovarian cancer stem cells.

PubMed

Kakar, Sham S; Parte, Seema; Carter, Kelsey; Joshua, Irving G; Worth, Christopher; Rameshwar, Pranela; Ratajczak, Mariusz Z

2017-09-26

Ovarian cancer is the fifth leading cause of deaths due to cancer among women in the United States. In 2017, 22,440 women are expected to be diagnosed with ovarian cancer and 14,080 women will die with it. Currently used chemotherapies (Cisplatin or platinum/taxane combination) targets cancer cells, but spares cancer stem cells (CSCs), which are responsible for tumor relapse leading to recurrence of cancer. Aldehyde dehydrogenase I (ALDH1) positive cancer stem cells are one of the major populations in ovarian tumor and have been related to tumor progression and metastasis. In our studies, we observed expression of ALDH1 in both ovarian surface epithelium (OSE) and cortex with high levels of expression in OSE in normal ovary and benign (BN) tumor, compared to borderline (BL) and high grade (HG) ovarian tumors. In contrast, high levels of expression of ALDH1 were observed in cortex in BL and HG tumors compared to normal ovary and BN tumor. Withaferin A (WFA) alone or in combination with cisplatin (CIS) significantly inhibited the spheroid formation (tumorigenic potential) of isolated ALDH1 CSCs in vitro and significantly reduced its expression in tumors collected from mice bearing orthotopic ovarian tumor compared to control. Treatment of animals with CIS alone significantly increased the ALDH1 CSC population in tumors, suggesting that CIS targets cancer cells but spares cancer stem cells, which undergo amplification. WFA and CIS combination suppresses the expression of securin an "oncogene", suggesting that securin may serve as a downstream signaling gene to mediate the antitumor effects of WFA.

Triaxial instabilities in rapidly rotating neutron stars

NASA Astrophysics Data System (ADS)

Basak, Arkadip

2018-06-01

Viscosity driven bar mode secular instabilities of rapidly rotating neutron stars are studied using LORENE/Nrotstar code. These instabilities set a more rigorous limit to the rotation frequency of a neutron star than the Kepler frequency/mass-shedding limit. The procedure employed in the code comprises of perturbing an axisymmetric and stationary configuration of a neutron star and studying its evolution by constructing a series of triaxial quasi-equilibrium configurations. Symmetry breaking point was found out for Polytropic as well as 10 realistic equations of states (EOS) from the CompOSE data base. The concept of piecewise polytropic EOSs has been used to comprehend the rotational instability of Realistic EOSs and validated with 19 different Realistic EOSs from CompOSE. The possibility of detecting quasi-periodic gravitational waves from viscosity driven instability with ground-based LIGO/VIRGO interferometers is also discussed very briefly.

Magnetic order and spin dynamics in La2O2Fe2OSe2 probed by 57Fe Mössbauer, 139La NMR, and muon-spin relaxation spectroscopy

NASA Astrophysics Data System (ADS)

Günther, M.; Kamusella, S.; Sarkar, R.; Goltz, T.; Luetkens, H.; Pascua, G.; Do, S.-H.; Choi, K.-Y.; Zhou, H. D.; Blum, C. G. F.; Wurmehl, S.; Büchner, B.; Klauss, H.-H.

2014-11-01

We present a detailed local probe study of the magnetic order in the oxychalcogenide La2O2Fe2OSe2 utilizing 57Fe Mössbauer, 139La NMR, and muon-spin relaxation spectroscopy. This system can be regarded as an insulating reference system of the Fe arsenide and chalcogenide superconductors. From the combination of the local probe techniques we identify a noncollinear magnetic structure similar to Sr2F2Fe2OS2 . The analysis of the magnetic order parameter yields an ordering temperature TN=90.1 K and a critical exponent of β =0.133 , which is close to the two-dimensional Ising universality class as reported in the related oxychalcogenide family.

Ultrasound-assisted extraction of flaxseed oil using immobilized enzymes.

PubMed

Long, Jing-jing; Fu, Yu-jie; Zu, Yuan-gang; Li, Ji; Wang, Wei; Gu, Cheng-bo; Luo, Meng

2011-11-01

An aqueous enzymatic process assisted by ultrasound extraction (AEP-UE) was applied to the extraction of oil from flaxseed (Linum usitatissimum L.). The highest oil recovery of 68.1% was obtained when ground flaxseed was incubated with 130 U/g of cellulase, pectinase, and hemicellulase for 12h, at 45°C and pH 5.0. The IC(50) values of oil obtained by AEP-UE and organic solvent extraction (OSE), as measured by DPPH scavenging activity essay, were 2.27 mg/mL and 3.31 mg/mL. The AEP-UE-derived oil had a 1.5% higher content of unsaturated fatty acids than the OSE-derived oil. AEP-UE is therefore a promising environmentally friendly method for large-scale preparation of flaxseed oil. Copyright © 2011 Elsevier Ltd. All rights reserved.

D-Amino acid oxidase-induced oxidative stress, 3-bromopyruvate and citrate inhibit angiogenesis, exhibiting potent anticancer effects.

PubMed

El Sayed, S M; El-Magd, R M Abou; Shishido, Y; Yorita, K; Chung, S P; Tran, D H; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

2012-10-01

Angiogenesis is critical for cancer growth and metastasis. Steps of angiogenesis are energy consuming, while vascular endothelial cells are highly glycolytic. Glioblastoma multiforme (GBM) is a highly vascular tumor and this enhances its aggressiveness. D-amino acid oxidase (DAO) is a promising therapeutic protein that induces oxidative stress upon acting on its substrates. Oxidative stress-energy depletion (OSED) therapy was recently reported (El Sayed et al., Cancer Gene Ther, 19, 1-18, 2012). OSED combines DAO-induced oxidative stress with energy depletion caused by glycolytic inhibitors such as 3-bromopyruvate (3BP), a hexokinase II inhibitor that depleted ATP in cancer cells and induced production of hydrogen peroxide. 3BP disturbs the Warburg effect and antagonizes effects of lactate and pyruvate (El Sayed et al., J Bioenerg Biomembr, 44, 61-79, 2012). Citrate is a natural organic acid capable of inhibiting glycolysis by targeting phosphofructokinase. Here, we report that DAO, 3BP and citrate significantly inhibited angiogenesis, decreased the number of vascular branching points and shortened the length of vascular tubules. OSED delayed the growth of C6/DAO glioma cells. 3BP combined with citrate delayed the growth of C6 glioma cells and decreased significantly the number and size of C6 glioma colonies in soft agar. Human GBM cells (U373MG) were resistant to chemotherapy e.g. cisplatin and cytosine arabinoside, while 3BP was effective in decreasing the viability and disturbing the morphology of U373MG cells.

IGHV1-69-Encoded Antibodies Expressed in Chronic Lymphocytic Leukemia React with Malondialdehyde–Acetaldehyde Adduct, an Immunodominant Oxidation-Specific Epitope

PubMed Central

Amir, Shahzada; Hartvigsen, Karsten; Hansen, Lotte F.; Woelkers, Douglas; Tsimikas, Sotirios; Binder, Christoph J.; Kipps, Thomas J.; Witztum, Joseph L.

2013-01-01

The immunoglobulins expressed by chronic lymphocytic leukemia (CLL) B cells are highly restricted, suggesting they are selected for binding either self or foreign antigen. Of the immunoglobulin heavy-chain variable (IGHV) genes expressed in CLL, IGHV1-69 is the most common, and often is expressed with little or no somatic mutation, and restricted IGHD and IGHJ gene usage. We found that antibodies encoded by one particular IGHV1-69 subset, designated CLL69C, with the HCDR3 encoded by the IGHD3-3 gene in reading frame 2 and IGHJ6, specifically bound to oxidation-specific epitopes (OSE), which are products of enhanced lipid peroxidation and a major target of innate natural antibodies. Specifically, CLL69C bound immunodominant OSE adducts termed MAA (malondialdehyde–acetaldehyde-adducts), which are found on apoptotic cells, inflammatory tissues, and atherosclerotic lesions. It also reacted specifically with MAA-specific peptide mimotopes. Light chain shuffling indicated that non-stochastically paired L chain of IGLV3-9 contributes to the antigen binding of CLL69C. A nearly identical CLL69C Ig heavy chain was identified from an MAA-enriched umbilical cord phage displayed Fab library, and a derived Fab with the same HCDR3 rearrangement displayed identical MAA-binding properties. These data support the concept that OSE (MAA-epitopes), which are ubiquitous products of inflammation, may play a role in clonal selection and expansion of CLL B cells. PMID:23840319

A Bone Health Intervention for Chinese Immigrants in Santa Clara County.

PubMed

Zou, Joanne; Hampton, Michelle DeCoux; Shade, Kate; Kaku, Leonard

Among Chinese immigrants, osteoporosis is undertreated, misdiagnosed, and a leading cause of fragility fractures. In orthopaedic surgery departments, prevention education and health behavior change programs are necessary to improve their bone health. The purpose of this study was to examine the effectiveness of an osteoporosis prevention education program on participants' self-efficacy with regard to exercise and nutrition when provided by an orthopaedic surgery team during an annual Chinese Health Fair in Santa Clara County, CA. This pilot study used a single-group pretest and posttest design. Chinese immigrants at risk of osteoporosis were recruited during a 1-day health fair. The Bone Health Intervention (BHI) included orthopaedic surgeon consultation, visual aids including osteoporosis images and bone models, a video that included a discussion on calcium and vitamin D in the Chinese diet and culturally-acceptable exercise, and osteoporosis educational handouts. The Osteoporosis Self-Efficacy Scale (OSES) was utilized to measure participants' confidence in the ability to participate in self-care behaviors related to physical activity and calcium intake before and after the intervention. Paired t tests were used to compare participants' OSES scores pre- and postintervention. There was a significant increase in mean OSES scores postintervention, indicating that the intervention could be an effective method of increasing participants' self-efficacy regarding calcium intake and time spent in exercising. These results indicate that a culturally meaningful education program can potentially reduce fragility fracture risk. Orthopaedic health providers are ideal candidates to deliver preventive care education to improve outcomes for Chinese immigrants.

Silk Film Topography Directs Collective Epithelial Cell Migration

PubMed Central

Rosenblatt, Mark I.

2012-01-01

The following study provides new insight into how surface topography dictates directed collective epithelial cell sheet growth through the guidance of individual cell movement. Collective cell behavior of migrating human corneal limbal-epithelial cell sheets were studied on highly biocompatible flat and micro-patterned silk film surfaces. The silk film edge topography guided the migratory direction of individual cells making up the collective epithelial sheet, which resulted in a 75% increase in total culture elongation. This was due to a 3-fold decrease in cell sheet migration rate efficiency for movement perpendicular to the topography edge. Individual cell migration direction is preferred in the parallel approach to the edge topography where localization of cytoskeletal proteins to the topography’s edge region is reduced, which results in the directed growth of the collective epithelial sheet. Findings indicate customized biomaterial surfaces may be created to direct both the migration rate and direction of tissue epithelialization. PMID:23185573

Ocular surface epithelium induces expression of human mucosal lymphocyte antigen (HML-1) on peripheral blood lymphocytes

PubMed Central

Gomes, J A P; Dua, H S; Rizzo, L V; Nishi, M; Joseph, A; Donoso, L A

2004-01-01

Background/aims: Peripheral blood CD8+ lymphocytes that home to mucosal surfaces express the human mucosal lymphocyte antigen (HML-1). At mucosal surfaces, including the ocular surface, only intraepithelial CD8+ lymphocytes express HML-1. These lymphocytes are retained in the intraepithelial compartment by virtue of the interaction between HML-1 and its natural ligand, E-cadherin, which is expressed on epithelial cells. The purpose of this study was to determine whether ocular surface epithelial cells (ocular mucosa) could induce the expression of human mucosal lymphocyte antigen on peripheral blood lymphocytes. Methods: Human corneal and conjunctival epithelial cells were co-cultured with peripheral blood lymphocytes. Both non-activated and activated lymphocytes were used in the experiments. After 7 days of incubation, lymphocytes were recovered and analysed for the antigens CD8/HML-1, CD4/HML-1, CD3/CD8, CD3/CD4, CD3/CD25, CD8/CD25, and CD4/CD25 by flowcytometry. Results: Significant statistical differences were observed in the CD8/HML-1 expression when conjunctival epithelial cells were co-cultured with non-activated and activated lymphocytes (p = 0.04 for each) and when corneal epithelial cells were co-cultured with non-activated lymphocytes (p = 0.03). Significant statistical difference in CD4/HML-1 expression was observed only when conjunctival epithelial cells were co-cultured with activated lymphocytes (p = 0.02). Conclusion: Ocular surface epithelial cells can induce the expression of human mucosal lymphocyte antigen on CD8+ (and to some extent on CD4+) lymphocytes. This may allow the retention of CD8+ and CD4+ lymphocytes within the epithelial compartment of the conjunctiva and play a part in mucosal homing of lymphocytes. PMID:14736792

Adhesion to the host cell surface is sufficient to mediate Listeria monocytogenes entry into epithelial cells

PubMed Central

Ortega, Fabian E.; Rengarajan, Michelle; Chavez, Natalie; Radhakrishnan, Prathima; Gloerich, Martijn; Bianchini, Julie; Siemers, Kathleen; Luckett, William S.; Lauer, Peter; Nelson, W. James; Theriot, Julie A.

2017-01-01

The intestinal epithelium is the first physiological barrier breached by the Gram-positive facultative pathogen Listeria monocytogenes during an in vivo infection. Listeria monocytogenes binds to the epithelial host cell receptor E-cadherin, which mediates a physical link between the bacterium and filamentous actin (F-actin). However, the importance of anchoring the bacterium to F-actin through E-cadherin for bacterial invasion has not been tested directly in epithelial cells. Here we demonstrate that depleting αE-catenin, which indirectly links E-cadherin to F-actin, did not decrease L. monocytogenes invasion of epithelial cells in tissue culture. Instead, invasion increased due to increased bacterial adhesion to epithelial monolayers with compromised cell–cell junctions. Furthermore, expression of a mutant E-cadherin lacking the intracellular domain was sufficient for efficient L. monocytogenes invasion of epithelial cells. Importantly, direct biotin-mediated binding of bacteria to surface lipids in the plasma membrane of host epithelial cells was sufficient for uptake. Our results indicate that the only requirement for L. monocytogenes invasion of epithelial cells is adhesion to the host cell surface, and that E-cadherin–mediated coupling of the bacterium to F-actin is not required. PMID:28877987

Study of the impact of satellite data in the analysis and forecasting of a SACZ episode using G3DVar

NASA Astrophysics Data System (ADS)

de Azevedo, H. B.; Goncalves, L.

2013-05-01

Earth observations from satellite have great importance and impact, in particular for operational weather and climate forecast centers in the Southern Hemisphere such as the Center for Weather Forecast and Climate Studies (CPTEC from its Portuguese acronym), a division of the Brazilian National Institute for Space Research (INPE from its Portuguese acronym). It is well known that such data is critical, in particular over Southern Hemisphere oceans where there is a lack of other information sources e.g. radiosonde and aircraft, where satellite data provides excellent spatial coverage with relatively frequent sampling in addition to sweeping continents, deserts, woodlands and other remote areas. Hence, studies like OSEs (Observing Systems Experiments) where we are able to test whether observational input data in an assimilation system degrades or improves analyzes and forecasts, are of great value. Furthermore OSEs applied to satellite observations are expected to show large impact due to its large amount of information compared to conventional observations. OSE also provides useful information on the efficiency of the system and this information can be used to improve the use of one or another observation system in the data assimilation process and to determine its relative importance compared to other observation systems. This is a technique where one or more observation systems are retained in the data assimilation process in order to assess the impact of the inclusion or exclusion of a particular observation on the quality of numerical weather prediction (NWP). One of the difficulties within the NWP nevertheless, is to predict the correct intensity of severe weather systems, which has great impact on the population. Over South America, an important weather system is the South Atlantic Convergence Zone (SACZ), which every year during summer yelds large amounts of rainfall over a band oriented northwest-southeast, extending from the Amazon to the Brazilian Southeast, with persistence of at least four days. It often is associated with the occurrence of landslides on slopes in heavily populated areas of Brazil such as Rio de Janeiro, killing and displacing hundreds to thousands of people. This work aims to study the impact of satellite data assimilated in the recently implemented Global 3DVar (G3DVar) assimilation system based on the Gridpoint Statistical Interpolation (GSI) in a situation of extreme event, such as the SACZ from January 8th 2013 to January 15th 2013. This system runs using a GCM from CPTEC/INPE (T299L64) corresponding to a horizontal resolution of approximately 44 km. A OSE was performed by removing the satellite data from the assimilation cycle and compared against a control experiment, were all available information (radiosondes, satellite, conventional observations, etc) was assimilated into the system. The OSE results presented in this work show the evaluation of the analyzes and up to 120 hours forecasts.

Novel materials to enhance corneal epithelial cell migration on keratoprosthesis.

PubMed

Karkhaneh, Akbar; Mirzadeh, Hamid; Ghaffariyeh, Alireza; Ebrahimi, Abdolali; Honarpisheh, Nazafarin; Hosseinzadeh, Masud; Heidari, Mohammad Hossein

2011-03-01

To introduce a new modification for silicone optical core Keratoprosthesis. Using mixtures of 2-hydroxyethyl methacrylate and acrylic acid polydimethylsiloxane (PDMS) films were modified with two-step oxygen plasma treatment, and then type I collagen was immobilised onto this modified surfaces. Both the biocompatibility of the modified films and cell behaviour on the surface of these films were investigated by in vitro tests, and formation of epithelial cell layer was evaluated by implantation of the modified films in the corneas of 10 rabbits. In vitro studies indicated that the number of attached and proliferated cells onto modified PDMS in comparison with the unmodified PDMS significantly increased. Histological studies showed that corneal epithelial cells migrated on the anterior surface of the modified films after 1week. The corneal epithelial cell formed an incomplete monolayer cellular sheet after 10days. A complete epithelialisation on the modified surface was formed after 21days. The epithelial layer persisted on the anterior surface of implant after 1-month and 3-month follow-up. This method may have potential use in silicone optical core Keratoprosthesis.

76 FR 72240 - Twenty-Seventh Meeting: RTCA Special Committee 206: Aeronautical Information and Meteorological...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-22

... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Twenty-Seventh Meeting: RTCA Special... Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 206..., 2011 FRAC OSED [[Page 72241

Dissipation processes in the insulating skyrmion compound Cu2OSeO3

NASA Astrophysics Data System (ADS)

Levatić, I.; Šurija, V.; Berger, H.; Živković, I.

2014-12-01

We present a detailed study of the phase diagram surrounding the skyrmion lattice (SkL) phase of Cu2OSe2O3 using high-precision magnetic ac susceptibility measurements. An extensive investigation of transition dynamics around the SkL phase using the imaginary component of the susceptibility revealed that at the conical-to-SkL transition a broad dissipation region exists with a complex frequency dependence. The analysis of the observed behavior within the SkL phase indicates a distribution of relaxation times intrinsically related to SkL. At the SkL-to-paramagnet transition a narrow first-order peak is found that exhibits a strong frequency and magnetic field dependence. Surprisingly, very similar dependence has been discovered for the first-order transition below the SkL phase, i.e., where the system enters the helical and conical state(s), indicating similar processes across the order-disorder transition.

Accelerating assimilation development for new observing systems using EFSO

NASA Astrophysics Data System (ADS)

Lien, Guo-Yuan; Hotta, Daisuke; Kalnay, Eugenia; Miyoshi, Takemasa; Chen, Tse-Chun

2018-03-01

To successfully assimilate data from a new observing system, it is necessary to develop appropriate data selection strategies, assimilating only the generally useful data. This development work is usually done by trial and error using observing system experiments (OSEs), which are very time and resource consuming. This study proposes a new, efficient methodology to accelerate the development using ensemble forecast sensitivity to observations (EFSO). First, non-cycled assimilation of the new observation data is conducted to compute EFSO diagnostics for each observation within a large sample. Second, the average EFSO conditionally sampled in terms of various factors is computed. Third, potential data selection criteria are designed based on the non-cycled EFSO statistics, and tested in cycled OSEs to verify the actual assimilation impact. The usefulness of this method is demonstrated with the assimilation of satellite precipitation data. It is shown that the EFSO-based method can efficiently suggest data selection criteria that significantly improve the assimilation results.

Stability of boron-doped graphene/copper interface: DFT, XPS and OSEE studies

NASA Astrophysics Data System (ADS)

Boukhvalov, D. W.; Zhidkov, I. S.; Kukharenko, A. I.; Slesarev, A. I.; Zatsepin, A. F.; Cholakh, S. O.; Kurmaev, E. Z.

2018-05-01

Two different types of boron-doped graphene/copper interfaces synthesized using two different flow rates of Ar through the bubbler containing the boron source were studied. X-ray photoelectron spectra (XPS) and optically stimulated electron emission (OSEE) measurements have demonstrated that boron-doped graphene coating provides a high corrosion resistivity of Cu-substrate with the light traces of the oxidation of carbon cover. The density functional theory calculations suggest that for the case of substitutional (graphitic) boron-defect only the oxidation near boron impurity is energetically favorable and creation of the vacancies that can induce the oxidation of copper substrate is energetically unfavorable. In the case of non-graphitic boron defects oxidation of the area, a nearby impurity is metastable that not only prevent oxidation but makes boron-doped graphene. Modeling of oxygen reduction reaction demonstrates high catalytic performance of these materials.

Ballistic low-temperature magnon heat conduction in the helimagnetic insulator Cu2OSeO3

NASA Astrophysics Data System (ADS)

Prasai, Narayan; Akopyan, Artem; Huang, Sunxiang; Cohn, Joshua L.; Trump, Benjamin; Marcus, Guy G.; McQueen, Tyrel M.

We report on the observation of magnon thermal conductivities κm 80 W/mK near T = 5 K in single crystals of the helimagnetic insulator Cu2OSeO3, exceeding those observed previously in any other ferro- or ferrimagnet by almost two orders of magnitude. Distinguished in applied magnetic field, both magnon and phonon thermal conductivities exhibit ballistic behavior below 1K, with mean free paths limited by specimen boundaries. Changes in κm through the helical-conical and conical-collinear spin-phase transitions with increasing applied field will also be discussed. This material is based on work supported by the U.S. DOE, Off. of BES, Div. of Mater. Sci. and Eng., under Grants No. DEFG02-12ER46888 (Miami), DEFG02-08ER46544 (JHU), and the NSF, Div. of Mater. Res., Sol. St. Chem., CAREER Grant No. DMR-1253562 (JHU).

Low-temperature spin-Seebeck effect in the helimagnetic insulator Cu2OSeO3

NASA Astrophysics Data System (ADS)

Akopyan, Artem; Prasai, Narayan; Huang, Sunxiang; Cohn, Joshua L.; Trump, Benjamin; Marcus, Guy G.; McQueen, Tyrel M.

We report on measurements of the longitudinal spin-Seebeck effect in single crystals of the helimagnetic insulator Cu2OSeO3 in the range 0 . 5 K <= T <= 15 K , using sputtered Pt thin films for spin-current detection. Simultaneous determination of magnon thermal conductivities for each specimen allows for a ``calibration'' of the spin current. The influence on the inverse spin-Hall signal of the helical-conical and conical-collinear magnetic phase transitions as well as different crystallographic orientations for the heat flow and applied magnetic field, will be discussed. This material is based on work supported by the U.S. DOE, Off. of BES, Div. of Mater. Sci. and Eng., under Grants No. DEFG02-12ER46888 (Miami), DEFG02-08ER46544 (JHU), and the NSF, Div. of Mater. Res., Sol. St. Chem., CAREER Grant No. DMR-1253562 (JHU).

The fibroblast surface markers FAP, anti-fibroblast, and FSP are expressed by cells of epithelial origin and may be altered during epithelial-to-mesenchymal transition.

PubMed

Kahounová, Zuzana; Kurfürstová, Daniela; Bouchal, Jan; Kharaishvili, Gvantsa; Navrátil, Jiří; Remšík, Ján; Šimečková, Šárka; Študent, Vladimír; Kozubík, Alois; Souček, Karel

2017-04-06

The identification of fibroblasts and cancer-associated fibroblasts from human cancer tissue using surface markers is difficult, especially because the markers used currently are usually not expressed solely by fibroblasts, and the identification of fibroblast-specific surface molecules is still under investigation. It was aimed to compare three commercially available antibodies in the detection of different surface epitopes of fibroblasts (anti-fibroblast, fibroblast activation protein α, and fibroblast surface protein). The specificity of their expression, employing fibroblast cell lines and tumor-derived fibroblasts from breast and prostate tissues was investigated. Both the established fibroblast cell line HFF-1 and ex vivo primary fibroblasts isolated from breast and prostate cancer tissues expressed the tested surface markers to different degrees. Surprisingly, those markers were expressed also by permanent cell lines of epithelial origin, both benign and cancer-derived (breast-cell lines MCF 10A, HMLE and prostate-cell lines BPH-1, DU 145, and PC-3). The expression of fibroblast activation protein α increased on the surface of previously described models of epithelial cells undergoing epithelial-to-mesenchymal transition in response to treatment with TGF-β1. To prove the co-expression of the fibroblast markers on cells of epithelial origin, we used freshly dissociated human prostate and breast cancer tissues. The results confirmed the co-expression of anti-fibroblast and fibroblast surface protein on CD31/CD45-negative/EpCAM-positive epithelial cells. In summary, our data support the findings that the tested fibroblast markers are not fibroblast specific and may be expressed also by cells of epithelial origin (e.g., cells undergoing EMT). Therefore, the expression of these markers should be interpreted with caution, and the combination of several epitopes for both positive (anti-fibroblast or fibroblast activation protein α) and negative (EpCAM) identification of fibroblasts from breast and prostate tumor tissues is advised. © 2017 International Society for Advancement of Cytometry. © 2017 International Society for Advancement of Cytometry.

Epstein-Barr Virus Infection of Polarized Epithelial Cells via the Basolateral Surface by Memory B Cell-Mediated Transfer Infection

PubMed Central

Shannon-Lowe, Claire; Rowe, Martin

2011-01-01

Epstein Barr virus (EBV) exhibits a distinct tropism for both B cells and epithelial cells. The virus persists as a latent infection of memory B cells in healthy individuals, but a role for infection of normal epithelial is also likely. Infection of B cells is initiated by the interaction of the major EBV glycoprotein gp350 with CD21 on the B cell surface. Fusion is triggered by the interaction of the EBV glycoprotein, gp42 with HLA class II, and is thereafter mediated by the core fusion complex, gH/gL/gp42. In contrast, direct infection of CD21-negative epithelial cells is inefficient, but efficient infection can be achieved by a process called transfer infection. In this study, we characterise the molecular interactions involved in the three stages of transfer infection of epithelial cells: (i) CD21-mediated co-capping of EBV and integrins on B cells, and activation of the adhesion molecules, (ii) conjugate formation between EBV-loaded B cells and epithelial cells via the capped adhesion molecules, and (iii) interaction of EBV glycoproteins with epithelial cells, with subsequent fusion and uptake of virions. Infection of epithelial cells required the EBV gH and gL glycoproteins, but not gp42. Using an in vitro model of normal polarized epithelia, we demonstrated that polarization of the EBV receptor(s) and adhesion molecules restricted transfer infection to the basolateral surface. Furthermore, the adhesions between EBV-loaded B cells and the basolateral surface of epithelial cells included CD11b on the B cell interacting with heparan sulphate moieties of CD44v3 and LEEP-CAM on epithelial cells. Consequently, transfer infection was efficiently mediated via CD11b-positive memory B cells but not by CD11b–negative naïve B cells. Together, these findings have important implications for understanding the mechanisms of EBV infection of normal and pre-malignant epithelial cells in vivo. PMID:21573183

GENETIC ACTIVITY PROFILES AND HAZARD ASSESSMENT

EPA Science Inventory

A methodology has been developed to display and evaluate multiple test quantitative information on genetic toxicants for purposes of hazard/risk assessment. ose information is collected from the open literature: either the lowest effective dose (LED) or the highest ineffective do...

Down-regulation of Pax6 is associated with abnormal differentiation of corneal epithelial cells in severe ocular surface diseases

PubMed Central

Li, W; Chen, Y-T; Hayashida, Y; Blanco, G; Kheirkah, A; He, H; Chen, S-Y; Liu, C-Y; Tseng, SCG

2010-01-01

Pax6 is the universal master control gene for eye morphogenesis. Other than retina and lens, Pax6 also expressed in the ocular surface epithelium from early gestation until the postnatal stage, in which little is known about the function of Pax6. In this study, corneal pannus tissues from patients with ocular surface diseases such as Stevens–Johnson syndrome (SJS), chemical burn, aniridia and recurrent pterygium were investigated. Our results showed that normal ocular surface epithelial cells expressed Pax6. However, corneal pannus epithelial cells from the above patients showed a decline or absence of Pax6 expression, accompanied by a decline or absence of K12 keratin but an increase of K10 keratin and filaggrin expression. Pannus basal epithelial cells maintained nuclear p63 expression and showed activated proliferation, evidenced by positive Ki67 and K16 keratin staining. On 3T3 fibroblast feeder layers, Pax6 immunostaining was negative in clones generated from epithelial cells harvested from corneal pannus from SJS or aniridia, but positive in those from the normal limbal epithelium; whereas western blots showed that some epithelial clones expanded from pannus retained Pax6 expression. Transient transfection of an adenoviral vector carrying EGFP–Pax6 transgenes into these Pax6− clones increased both Pax6 and K12 keratin expression. These results indicate that Pax6 helps to maintain the normal corneal epithelial phenotype postnatally, and that down-regulation of Pax6 is associated with abnormal epidermal differentiation in severe ocular surface diseases. Reintroduction of activation of the Pax6 gene might be useful in treating squamous metaplasia of the ocular surface epithelium. PMID:18027901

ARMOR3D: A 3D multi-observations T,S,U,V product of the ocean

NASA Astrophysics Data System (ADS)

Verbrugge, Nathalie; Mulet, Sandrine; Guinehut, Stéphanie; Buongiorno-Nardelli, Bruno

2017-04-01

To have a synoptic view of the 3D ocean to pursue oceanic studies, an observed gridded product can be often useful instead of using raw observations which can be irregularly distributed in space and time as the in situ profiles for instance or which offer only a surface view of the ocean as satellite data. The originality of the ARMOR3D observation based product is to take advantage of the strengths of these 2 types of data by combining satellite SLA, SST, SSS datasets with in situ T, S vertical profiles in order to build a global 3D weekly temperature, salinity and geostrophic velocities fields at a spatial 1/4° resolution. The mesoscale content of the satellite data and the vertical sampling of the in situ profiles are complementary in this statistical approach. ARMOR3D is part of the CMEMS project through the GLO-OBS component. A full reprocessing from 1993 to 2016 and near-real-time fields from 1/1/2014 to present are available through the CMEMS web portal. The range of applications of this product is wide: OSE studies have been already conducted to evaluate the ARGO network and in 2017, OSE and OSSE will be performed in the western Tropical Pacific as part of the TPOS2020 project (Tropical Pacific Observing System for 2020 Pacific). The product is useful also to study mesoscale eddies characteristics as well as links with the biogeochemical processes. For example, in 2015, ARMOR3D fields have been used as inputs of a micronekton model within the framework of the ESA OSMOSIS Project. Furthermore, ARMOR3D also contributes to the annual CMEMS Ocean State Report.

Physical stress and bacterial colonization

PubMed Central

Otto, Michael

2014-01-01

Bacterial surface colonizers are subject to a variety of physical stresses. During the colonization of human epithelia such as on the skin or the intestinal mucosa, bacteria mainly have to withstand the mechanical stress of being removed by fluid flow, scraping, or epithelial turnover. To that end, they express a series of molecules to establish firm attachment to the epithelial surface, such as fibrillar protrusions (pili) and surface-anchored proteins that bind to human matrix proteins. In addition, some bacteria – in particular gut and urinary tract pathogens – use internalization by epithelial cells and other methods such as directed inhibition of epithelial turnover to ascertain continued association with the epithelial layer. Furthermore, many bacteria produce multi-layered agglomerations called biofilms with a sticky extracellular matrix, providing additional protection from removal. This review will give an overview over the mechanisms human bacterial colonizers have to withstand physical stresses with a focus on bacterial adhesion. PMID:25212723

Rebamipide suppresses PolyI:C-stimulated cytokine production in human conjunctival epithelial cells.

PubMed

Ueta, Mayumi; Sotozono, Chie; Yokoi, Norihiko; Kinoshita, Shigeru

2013-09-01

We previously documented that ocular surface epithelial cells could regulate ocular surface inflammation and suggested that, while Toll-like receptor 3 upregulates, EP3, one of the prostaglandin E2 receptors, downregulates ocular surface inflammation. Others reported that rebamipide, a gastroprotective drug, could not only increase the gastric mucus production, but also suppressed gastric mucosal inflammation and that it was dominantly distributed in mucosal tissues. The eyedrop form of rebamipide, approved in Japan for use in the treatment of dry eye diseases, upregulates mucin secretion and production, thereby suppressing superficial punctate keratopathy on the ocular surface of patients with this disease. In the current study, we investigated whether rebamipide has anti- inflammatory effects on the ocular surface. To examine the effects of rebamipide on polyI:C-induced cytokine expression by primary human conjunctival epithelial cells, we used enzyme-linked immunosorbent assay and quantitative reverse transcription-polymerase chain reaction assay. We studied the effects of rebamipide on ocular surface inflammation in our murine experimental allergic conjunctivitis (EAC) model. Rebamipide could suppress polyI:C-induced cytokine production and the expression of mRNAs for CXCL10, CXCL11, RANTES, MCP-1, and IL-6 in human conjunctival epithelial cells. In our EAC model, the topical administration of rebamipide suppressed conjunctival allergic eosinophil infiltration. The topical application of rebamipide on the ocular surface might suppress ocular surface inflammation by suppressing the production of cytokines by ocular surface epithelial cells.

Hertwig's Epithelial Root Sheath Fate during Initial Cellular Cementogenesis in Rat Molars.

PubMed

Yamamoto, Tsuneyuki; Yamada, Tamaki; Yamamoto, Tomomaya; Hasegawa, Tomoka; Hongo, Hiromi; Oda, Kimimitsu; Amizuka, Norio

2015-06-29

To elucidate the fate of the epithelial root sheath during initial cellular cementogenesis, we examined developing maxillary first molars of rats by immunohistochemistry for keratin, vimentin, and tissue non-specific alkaline phosphatase (TNALP) and by TdT-mediated dUTP nick end labeling (TUNEL). The advancing root end was divided into three sections, which follow three distinct stages of initial cellular cementogenesis: section 1, where the epithelial sheath is intact; section 2, where the epithelial sheath becomes fragmented; and section 3, where initial cellular cementogenesis begins. After fragmentation of the epithelial sheath, many keratin-positive epithelial sheath cells were embedded in the rapidly growing cellular cementum. A few unembedded epithelial cells located on the cementum surface. Dental follicle cells, precementoblasts, and cementoblasts showed immunoreactivity for vimentin and TNALP. In all three sections, there were virtually no cells possessing double immunoreactivity for vimentin-keratin or TNALP-keratin and only embedded epithelial cells showed TUNEL reactivity. Taken together, these findings suggest that: (1) epithelial sheath cells divide into two groups; one group is embedded in the cementum and thereafter dies by apoptosis, and the other survives on the cementum surface as epithelial cell rests of Malassez; and (2) epithelial sheath cells do not undergo epithelial-mesenchymal transition during initial cellular cementogenesis.

Hertwig’s Epithelial Root Sheath Fate during Initial Cellular Cementogenesis in Rat Molars

PubMed Central

Yamamoto, Tsuneyuki; Yamada, Tamaki; Yamamoto, Tomomaya; Hasegawa, Tomoka; Hongo, Hiromi; Oda, Kimimitsu; Amizuka, Norio

2015-01-01

To elucidate the fate of the epithelial root sheath during initial cellular cementogenesis, we examined developing maxillary first molars of rats by immunohistochemistry for keratin, vimentin, and tissue non-specific alkaline phosphatase (TNALP) and by TdT-mediated dUTP nick end labeling (TUNEL). The advancing root end was divided into three sections, which follow three distinct stages of initial cellular cementogenesis: section 1, where the epithelial sheath is intact; section 2, where the epithelial sheath becomes fragmented; and section 3, where initial cellular cementogenesis begins. After fragmentation of the epithelial sheath, many keratin-positive epithelial sheath cells were embedded in the rapidly growing cellular cementum. A few unembedded epithelial cells located on the cementum surface. Dental follicle cells, precementoblasts, and cementoblasts showed immunoreactivity for vimentin and TNALP. In all three sections, there were virtually no cells possessing double immunoreactivity for vimentin-keratin or TNALP-keratin and only embedded epithelial cells showed TUNEL reactivity. Taken together, these findings suggest that: (1) epithelial sheath cells divide into two groups; one group is embedded in the cementum and thereafter dies by apoptosis, and the other survives on the cementum surface as epithelial cell rests of Malassez; and (2) epithelial sheath cells do not undergo epithelial-mesenchymal transition during initial cellular cementogenesis. PMID:26160988

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.

Effects of pH and anions on the sorption of selenium ions onto magnetite.

PubMed

Kim, Seung Soo; Min, Je Ho; Lee, Jae Kwang; Baik, Min Hoon; Choi, Jong-Won; Shin, Hyung Seon

2012-02-01

This study analyzes the influence of carbonate and silicate, which are generally abundant in granitic groundwater, on the sorption of selenium ions onto magnetite in order to understand the behaviors of selenium in a radioactive waste repository. Selenite was sorbed onto magnetite very well below pH 10, but silicate and carbonate hindered the sorption of selenite onto magnetite. On the other hand, little selenate was sorbed onto magnetite in neutral and weak alkaline solutions of 0.02 M NaNO(3) or NaClO(4), matching the ionic strength in a granitic groundwater, even though silicate or carbonate was not contained in the solutions. The surface complexation constants between selenite and magnetite were obtained by using a geochemical program, FITEQL 4.0, from the experimental data, and the formation of an inner-sphere surface complex such as =FeOSeO(2)(-) was suggested for the sorption of selenite onto magnetite from the diffuse double layer model calculation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Association of Cell Surface Mucins with Galectin-3 Contributes to the Ocular Surface Epithelial Barrier*

PubMed Central

Argüeso, Pablo; Guzman-Aranguez, Ana; Mantelli, Flavio; Cao, Zhiyi; Ricciuto, Jessica; Panjwani, Noorjahan

2009-01-01

Maintenance of an intact mucosal barrier is critical to preventing damage to and infection of wet-surfaced epithelia. The mechanism of defense has been the subject of much investigation, and there is evidence now implicating O-glycosylated mucins on the epithelial cell surface. Here we investigate a new role for the carbohydrate-binding protein galectin-3 in stabilizing mucosal barriers through its interaction with mucins on the apical glycocalyx. Using the surface of the eye as a model system, we found that galectin-3 colocalized with two distinct membrane-associated mucins, MUC1 and MUC16, on the apical surface of epithelial cells and that both mucins bound to galectin-3 affinity columns in a galactose-dependent manner. Abrogation of the mucin-galectin interaction in four different mucosal epithelial cell types using competitive carbohydrate inhibitors of galectin binding, β-lactose and modified citrus pectin, resulted in decreased levels of galectin-3 on the cell surface with concomitant loss of barrier function, as indicated by increased permeability to rose bengal diagnostic dye. Similarly, down-regulation of mucin O-glycosylation using a stable tetracycline-inducible RNA interfering system to knockdown c1galt1 (T-synthase), a critical galactosyltransferase required for the synthesis of core 1 O-glycans, resulted in decreased cell surface O-glycosylation, reduced cell surface galectin-3, and increased epithelial permeability. Taken together, these results suggest that galectin-3 plays a key role in maintaining mucosal barrier function through carbohydrate-dependent interactions with cell surface mucins. PMID:19556244

USE OF GENOTOXIC ACTIVITY PROFILES IN ASSESSMENT OF CARCINOGENESIS AND TRANSMISSIBLE GENETIC EFFECTS

EPA Science Inventory

A methodology has been developed to display and evaluate multiple test quantitative information on genetic toxicants for purposes of assessing carcinogenesis and transmissible genetic effects. ose Information is collected from the open literature: either the lowest effective dose...

Mechanisms of the epithelial-to-mesenchymal transition in sea urchin embryos

PubMed Central

Katow, Hideki

2015-01-01

Sea urchin mesenchyme is composed of the large micromere-derived spiculogenetic primary mesenchyme cells (PMC), veg2-tier macromere-derived non-spiculogenetic mesenchyme cells, the small micromere-derived germ cells, and the macro- and mesomere-derived neuronal mesenchyme cells. They are formed through the epithelial-to-mesenchymal transition (EMT) and possess multipotency, except PMCs that solely differentiate larval spicules. The process of EMT is associated with modification of epithelial cell surface property that includes loss of affinity to the apical and basal extracellular matrices, inter-epithelial cell adherens junctions and epithelial cell surface-specific proteins. These cell surface structures and molecules are endocytosed during EMT and utilized as initiators of cytoplasmic signaling pathways that often initiate protein phosphorylation to activate the gene regulatory networks. Acquisition of cell motility after EMT in these mesenchyme cells is associated with the expression of proteins such as Lefty, Snail and Seawi. Structural simplicity and genomic database of this model will further promote detailed EMT research. PMID:26716069

Treatment with solubilized Silk-Derived Protein (SDP) enhances rabbit corneal epithelial wound healing.

PubMed

Abdel-Naby, Waleed; Cole, Brigette; Liu, Aihong; Liu, Jingbo; Wan, Pengxia; Schreiner, Ryan; Infanger, David W; Paulson, Nicholas B; Lawrence, Brian D; Rosenblatt, Mark I

2017-01-01

There is a significant clinical need to improve current therapeutic approaches to treat ocular surface injuries and disease, which affect hundreds of millions of people annually worldwide. The work presented here demonstrates that the presence of Silk-Derived Protein (SDP) on the healing rabbit corneal surface, administered in an eye drop formulation, corresponds with an enhanced epithelial wound healing profile. Rabbit corneas were denuded of their epithelial surface, and then treated for 72-hours with either PBS or PBS containing 5 or 20 mg/mL SDP in solution four times per day. Post-injury treatment with SDP formulations was found to accelerate the acute healing phase of the injured rabbit corneal epithelium. In addition, the use of SDP corresponded with an enhanced tissue healing profile through the formation of a multi-layered epithelial surface with increased tight junction formation. Additional biological effects were also revealed that included increased epithelial proliferation, and increased focal adhesion formation with a corresponding reduction in the presence of MMP-9 enzyme. These in vivo findings demonstrate for the first time that the presence of SDP on the injured ocular surface may aid to improve various steps of rabbit corneal wound healing, and provides evidence that SDP may have applicability as an ingredient in therapeutic ophthalmic formulations.

Antiadhesive Character of Mucin O-glycans at the Apical Surface of Corneal Epithelial Cells

PubMed Central

Sumiyoshi, Mika; Ricciuto, Jessica; Tisdale, Ann; Gipson, Ilene K.; Mantelli, Flavio; Argüeso, Pablo

2008-01-01

Purpose Prolonged contact of opposite mucosal surfaces, which occurs on the ocular surface, oral cavity, reproductive tract, and gut, requires a specialized apical cell surface that prevents adhesion. The purpose of this study was to evaluate the contribution of mucin O-glycans to the antiadhesive character of human corneal–limbal epithelial (HCLE) cells. Methods Mucin O-glycan biosynthesis in HCLE cells was disrupted by metabolic interference with benzyl-α-GalNAc. The cell surface mucin MUC16 and its carbohydrate epitope H185 were detected by immunofluorescence and Western blot. HCLE cell surface features were assessed by field emission scanning electron microscopy. Cell–cell adhesion assays were performed under static conditions and in a parallel plate laminar flow chamber. Results Benzyl-α-GalNAc disrupted the biosynthesis of O-glycans without affecting apomucin biosynthesis or cell surface morphology. Static adhesion assays showed that the apical surface of differentiated HCLE cells expressing MUC16 and H185 was more antiadhesive than undifferentiated HCLE cells, which lacked MUC16. Abrogation of mucin O-glycosylation in differentiated cultures with benzyl-α-GalNAc resulted in increased adhesion of applied corneal epithelial cells and corneal fibroblasts. The antiadhesive effect of mucin O-glycans was further demonstrated by fluorescence video microscopy in dynamic flow adhesion assays. Cationized ferritin labeling of the cell surface indicated that anionic repulsion did not contribute to the antiadhesive character of the apical surface. Conclusions These results indicate that epithelial O-glycans contribute to the antiadhesive properties of cell surface–associated mucins in corneal epithelial cells and suggest that alterations in mucin O-glycosylation are involved in the pathology of drying mucosal diseases (e.g., dry eye). PMID:18172093

Interface handbook : National Airspace System (NAS) Open System Environment (OSE) application services

DOT National Transportation Integrated Search

1997-06-27

The Intelligent Vehicle Highway System (IVHS) program is a major new national program which has dramatically come of age in the last five years. Internationally, similar events have also occurred in both Japan and Europe. However, what may be suspect...

76 FR 19376 - Statement of Organizations, Functions, and Delegations of Authority

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-07

... safety mission. These outside groups include academic organizations, private organizations, and other Federal Agencies. 3. Coordinates the access to large databases for pharmacoepidemiologic and..., procedures, training, and security or databases available to OSE. 3. Acts as focal point for all hardware...

Two-step transition in a magnetoelectric ferrimagnet Cu2OSeO3

NASA Astrophysics Data System (ADS)

Živković, I.; Pajić, D.; Ivek, T.; Berger, H.

2012-06-01

We report a detailed single-crystal investigation of a magnetoelectric ferrimagnet Cu2OSeO3 using dc magnetization and ac susceptibility along the three principal directions [100], [110], and [111]. We have observed that in small magnetic fields two magnetic transitions occur, one at Tc=57 K and the second one at TN=58 K. At Tc the nonlinear susceptibility reveals the emergence of the ferromagnetic component and below Tc the magnetization measurements show the splitting between field-cooled and zero-field-cooled regimes. Above 1000 Oe the magnetization saturates and the system is in a single domain state. The temperature dependence of the saturation below Tc can be well described by μ(T)=μ(0)[1-(T/Tc)2]β, with μ(0)=0.56μB/Cu, corresponding to the 3-up-1-down configuration. The dielectric constant measured on a thin single crystal shows a systematic deviation below the transition, indicating an intrinsic magnetoelectric effect.

Direct experimental determination of the topological winding number of skyrmions in Cu2OSeO3

NASA Astrophysics Data System (ADS)

Zhang, S. L.; van der Laan, G.; Hesjedal, T.

2017-02-01

The mathematical concept of topology has brought about significant advantages that allow for a fundamental understanding of the underlying physics of a system. In magnetism, the topology of spin order manifests itself in the topological winding number which plays a pivotal role for the determination of the emergent properties of a system. However, the direct experimental determination of the topological winding number of a magnetically ordered system remains elusive. Here, we present a direct relationship between the topological winding number of the spin texture and the polarized resonant X-ray scattering process. This relationship provides a one-to-one correspondence between the measured scattering signal and the winding number. We demonstrate that the exact topological quantities of the skyrmion material Cu2OSeO3 can be directly experimentally determined this way. This technique has the potential to be applicable to a wide range of materials, allowing for a direct determination of their topological properties.

Resonant x-ray scattering from a skyrmion lattice

NASA Astrophysics Data System (ADS)

Roy, S.; Langner, M. C.; Mishra, S. K.; Lee, J. C. T.; Shi, X. W.; Hossain, M. A.; Chuang, Y.-D.; Kevan, S. D.; Schoenlein, R. W.; Seki, S.; Tokura, Y.

2014-03-01

Topologically protected novel phases in condensed matter systems are a current research topic of tremendous interest due to both the unique physics and their potential in device applications. Skyrmions are a topological phase that in magnetic systems manifest as a hexagonal lattice of spin-swirls. We report the first observation of the skyrmion lattice using resonant soft x-ray diffraction in Cu2OSeO3, a cubic insulator that exhibits degenerate helical magnetic structures along <100> axes in zero magnetic field. Within a narrow window of temperature and applied magnetic field we observed the six fold symmetric satellite peaks due to the skyrmion lattice around the (001) lattice Bragg peak. As a function of incident photon energy a rotational splitting of the skyrmion satellite peaks was observed that we ascribe to the two Cu sublattices of Cu2OSeO3, with different magnetically active orbitals. The splitting implies a long wavelength modulation of the skyrmion lattice. Work supported by U.S. DOE.

RhoA regulates actin network dynamics during apical surface emergence in multiciliated epithelial cells

PubMed Central

Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté

2017-01-01

ABSTRACT Homeostatic replacement of epithelial cells from basal precursors is a multistep process involving progenitor cell specification, radial intercalation and, finally, apical surface emergence. Recent data demonstrate that actin-based pushing under the control of the formin protein Fmn1 drives apical emergence in nascent multiciliated epithelial cells (MCCs), but little else is known about this actin network or the control of Fmn1. Here, we explore the role of the small GTPase RhoA in MCC apical emergence. Disruption of RhoA function reduced the rate of apical surface expansion and decreased the final size of the apical domain. Analysis of cell shapes suggests that RhoA alters the balance of forces exerted on the MCC apical surface. Finally, quantitative time-lapse imaging and fluorescence recovery after photobleaching studies argue that RhoA works in concert with Fmn1 to control assembly of the specialized apical actin network in MCCs. These data provide new molecular insights into epithelial apical surface assembly and could also shed light on mechanisms of apical lumen formation. PMID:28089989

RhoA regulates actin network dynamics during apical surface emergence in multiciliated epithelial cells.

PubMed

Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté; Wallingford, John B

2017-01-15

Homeostatic replacement of epithelial cells from basal precursors is a multistep process involving progenitor cell specification, radial intercalation and, finally, apical surface emergence. Recent data demonstrate that actin-based pushing under the control of the formin protein Fmn1 drives apical emergence in nascent multiciliated epithelial cells (MCCs), but little else is known about this actin network or the control of Fmn1. Here, we explore the role of the small GTPase RhoA in MCC apical emergence. Disruption of RhoA function reduced the rate of apical surface expansion and decreased the final size of the apical domain. Analysis of cell shapes suggests that RhoA alters the balance of forces exerted on the MCC apical surface. Finally, quantitative time-lapse imaging and fluorescence recovery after photobleaching studies argue that RhoA works in concert with Fmn1 to control assembly of the specialized apical actin network in MCCs. These data provide new molecular insights into epithelial apical surface assembly and could also shed light on mechanisms of apical lumen formation. © 2017. Published by The Company of Biologists Ltd.

The name of the -ose: An editorial on carbohydrate nomenclature

USDA-ARS?s Scientific Manuscript database

What’s in a name? The term "sugar" is usually applied to the monosaccharides, disaccharides, and lower oligosaccharides, although "carbohydrate" ("hydrate de carbone") was originally used only for monosaccharides, because their composition can be expressed as Cn(H2O)n. Historically, sugars were name...

Wilms tumor gene product: sensitive and contextually specific marker of serous carcinomas of ovarian surface epithelial origin.

PubMed

Hwang, Harry; Quenneville, Louise; Yaziji, Hadi; Gown, Allen M

2004-06-01

Carcinomas of ovarian surface epithelial origin can arise from, and often present at, extraovarian sites. There are few available markers for the positive identification of carcinomas of ovarian surface epithelial origin, which might aid in distinguishing them from metastatic carcinomas, such as of breast, colon, or lung origin. Recently, the Wilms tumor gene product (WT-1) has been shown to be expressed in ovarian surface and mesothelial epithelium. We tested the hypothesis that WT-1 would be a sensitive and specific marker of ovarian surface epithelium carcinomas. An archived series of 116 ovarian carcinomas (57 serous [43 ovarian, 14 extraovarian], 31 mucinous, 15 clear cell, 13 endometrioid), 118 breast carcinomas, 46 colonic carcinomas, and 45 nonsmall cell lung cancers were selected. A polyclonal antibody to the WT-1 gene product was applied to deparaffinized, formalin-fixed tissue sections after epitope retrieval. Fifty-two of 57 (93%) serous carcinomas of ovarian surface epithelial origin were WT-1-positive, in a nuclear pattern, with virtually all the tumor cell population positive in the majority of cases. None of the mucinous, clear cell, or endometrioid ovarian cancers were positive, and only 8 of 118 breast, 0 of 46 colonic, and 0 of 45 lung nonsmall cell carcinomas were WT-1-positive. These findings demonstrate that WT-1 is a highly sensitive and specific marker of serous carcinomas of ovarian surface epithelial origin (both ovarian and extraovarian). These results also contradict recent reports demonstrating WT-1 expression in both breast and lung carcinomas.

Impacts of distinct observations during the 2009 Prince William Sound field experiment: A data assimilation study

NASA Astrophysics Data System (ADS)

Li, Zhijin; Chao, Yi; Farrara, John D.; McWilliams, James C.

2013-07-01

A set of data assimilation experiments, known as Observing System Experiments (OSEs) are performed to assess the relative impacts of different types of observations acquired during the 2009 Prince William Sound Field Experiment. The observations assimilated consist primarily of two types: High Frequency (HF) radar surface velocities and vertical profiles of temperature/salinity (T/S) measured by ships, moorings, an Autonomous Underwater Vehicle and a glider. The impact of all the observations, HF radar surface velocities, and T/S profiles is assessed. Without data assimilation, a frequently occurring cyclonic eddy in the central Sound is overly persistent and intense. The assimilation of the HF radar velocities effectively reduces these biases and improves the representation of the velocities as well as the T/S fields in the Sound. The assimilation of the T/S profiles improves the large scale representation of the temperature/salinity and also the velocity field in the central Sound. The combination of the HF radar surface velocities and sparse T/S profiles results in an observing system capable of representing the circulation in the Sound reliably and thus producing analyses and forecasts with useful skill.

ICAM-1 mediates surface contact between neutrophils and keratocytes following corneal epithelial abrasion in the mouse

USDA-ARS?s Scientific Manuscript database

Corneal epithelial abrasion elicits an inflammatory response involving neutrophil (PMN) recruitment from the limbal vessels into the corneal stroma. These migrating PMNs make surface contact with collagen and stromal keratocytes. Using mice deficient in PMN integrin CD18, we previously showed that P...

Regulation of Biofilm Formation in Escherichia coli O157:H7

USDA-ARS?s Scientific Manuscript database

Escherichia coli O157:H7 encodes a variety of genetic factors for adherence to epithelial cells and to abiotic surfaces. While adherence to epithelial cells culminates in the formation of characteristic attaching and effacing (A/E) lesions, adherence to abiotic surfaces represents a prelude to the f...

Expression of Opacity Proteins Interferes with the Transmigration of Neisseria gonorrhoeae across Polarized Epithelial Cells.

PubMed

Stein, Daniel C; LeVan, Adriana; Hardy, Britney; Wang, Liang-Chun; Zimmerman, Lindsey; Song, Wenxia

2015-01-01

Neisseria gonorrhoeae (GC) establishes infection at the mucosal surface of the human genital tract, most of which is lined with polarized epithelial cells. GC can cause localized as well as disseminated infections, leading to various complications. GC constantly change their surface structures via phase and antigenic variation, which has been implicated as a means for GC to establish infection at various anatomic locations of male and female genital tracks. However, the exact contribution of each surface molecule to bacterial infectivity remains elusive due to their phase variation. Using a GC derivative that is genetically devoid of all opa genes (MS11∆Opa), this study shows that Opa expression interferes with GC transmigration across polarized human epithelial cells. MS11∆Opa transmigrates across polarized epithelial cells much faster and to a greater extent than MS11Opa+, while adhering at a similar level as MS11Opa+. When MS11Opa+, able to phase vary Opa expression, was inoculated, only those bacteria that turn off Opa expression transmigrate across the polarized epithelial monolayer. Similar to bacteria alone or co-cultured with non-polarized epithelial cells, MS11∆Opa fails to form large microcolonies at the apical surface of polarized epithelial cells. Apical inoculation of MS11Opa+, but not MS11∆Opa, induces the recruitment of the Opa host-cell receptor carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) to the apical junction and the vicinity of bacterial adherent sites. Our results suggest that Opa expression limits gonococcal ability to invade into subepithelial tissues by forming tight interactions with neighboring bacteria and by inducing CEACAM redistribution to cell junctions.

Ocular surface reconstruction with a tissue-engineered nasal mucosal epithelial cell sheet for the treatment of severe ocular surface diseases.

PubMed

Kobayashi, Masakazu; Nakamura, Takahiro; Yasuda, Makoto; Hata, Yuiko; Okura, Shoki; Iwamoto, Miyu; Nagata, Maho; Fullwood, Nigel J; Koizumi, Noriko; Hisa, Yasuo; Kinoshita, Shigeru

2015-01-01

Severe ocular surface diseases (OSDs) with severe dry eye can be devastating and are currently some of the most challenging eye disorders to treat. To investigate the feasibility of using an autologous tissue-engineered cultivated nasal mucosal epithelial cell sheet (CNMES) for ocular surface reconstruction, we developed a novel technique for the culture of nasal mucosal epithelial cells expanded ex vivo from biopsy-derived human nasal mucosal tissues. After the protocol, the CNMESs had 4-5 layers of stratified, well-differentiated cells, and we successfully generated cultured epithelial sheets, including numerous goblet cells. Immunohistochemistry confirmed the presence of keratins 3, 4, and 13; mucins 1, 16, and 5AC; cell junction and basement membrane assembly proteins; and stem/progenitor cell marker p75 in the CNMESs. We then transplanted the CNMESs onto the ocular surfaces of rabbits and confirmed the survival of this tissue, including the goblet cells, up to 2 weeks. The present report describes an attempt to overcome the problems of treating severe OSDs with the most severe dry eye by treating them using tissue-engineered CNMESs to supply functional goblet cells and to stabilize and reconstruct the ocular surface. The present study is a first step toward assessing the use of tissue-engineered goblet-cell transplantation of nonocular surface origin for ocular surface reconstruction. ©AlphaMed Press.

Surface Papillary Epithelial Hyperplasia (Rough Mucosa) is a Helpful Clue for Identification of Polymorphous Low-Grade Adenocarcinoma.

PubMed

Chi, Angela C; Neville, Brad W

2015-06-01

The purpose of this study is to evaluate surface papillary epithelial hyperplasia, a microscopic finding that corresponds to the clinical finding of rough or stippled mucosa, as a predictor of polymorphous low-grade adenocarcinoma (PLGA). We conducted a retrospective review of minor salivary gland neoplasms submitted to our biopsy service from 1991 to 2013. Our review was limited to lesions involving the oral cavity/soft palate with the following diagnoses: PLGA, pleomorphic adenoma (PA), mucoepidermoid carcinoma (MEC), and adenoid cystic carcinoma (ACC). A total of 202 minor salivary gland neoplasms were included in the study. Among cases in which surface epithelium was present for evaluation (n = 112), surface papillary epithelial hyperplasia was evident in 30 % of PLGA and 1 % of non-PLGA (i.e., MEC, ACC, PA). The greater frequency of surface papillary epithelial hyperplasia in the PLGA versus non-PLGA cases and in the benign versus malignant cases was significant (p = .0001 and p = .041, respectively). The sensitivity and specificity of papillary epithelial hyperplasia for PLGA were 30 % (95 % confidence interval (CI) 11.97-54.27 %) and 99 % (95 % CI 94-99.82 %), respectively. The clinical presentation of PLGA appeared relatively nonspecific, with all analyzed tumor types exhibiting a predilection for females, middle-aged to older adults, palatal location, pink/tan/normal color, and firm consistency. In conclusion, papillary epithelial hyperplasia was evident in only a minority of PLGA. However, when present within the context of a palatal salivary gland neoplasm, it appears to indicate a high probability of PLGA. Accordingly, rough mucosa may be a useful clinical pearl for identification of PLGA.

Differential effect of rebamipide on transmembrane mucin biosynthesis in stratified ocular surface epithelial cells.

PubMed

Uchino, Yuichi; Woodward, Ashley M; Argüeso, Pablo

2016-12-01

Mucins are a group of highly glycosylated glycoproteins responsible for the protection of wet-surfaced epithelia. Recent data indicate that transmembrane mucins differ in their contribution to the protective function of the ocular surface, with MUC16 being the most effective barrier on the apical surface glycocalyx. Here, we investigated the role of the mucoprotective drug rebamipide in the regulation of transmembrane mucin biosynthesis using stratified cultures of human corneal and conjunctival epithelial cells. We find that the addition of rebamipide to corneal, but not conjunctival, epithelial cells increased MUC16 protein biosynthesis. Rebamipide did not affect the levels of MUC1, 4 and 20 compared to control. In these experiments, rebamipide had no effect on the expression levels of Notch intracellular domains, suggesting that the rebamipide-induced increase in MUC16 biosynthesis in differentiated corneal cultures is not regulated by Notch signaling. Overall these findings indicate that rebamipide induces the differential upregulation of MUC16 in stratified cultures of human corneal epithelial cells, which may have implications to the proper restoration of barrier function in ocular surface disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Quantitative characterization of nuclear polymorphism of the epithelial cells in fibroadenomatosis and cancer of the breast].

PubMed

Ganina, K P; Petunin, Iu I; Timoshenko, Ia G

1989-01-01

A method for quantitative analysis of epithelial cell nuclear polymorphism was suggested, viz. identification of general statistical population using Petunin's criterion. This criterion was employed to assess heterogeneity of visible surface of interphase epithelial cell nuclei and to assay nuclear DNA level in fibroadenomatous hyperplasia and cancer of the breast. Heterogeneity index (h), alongside with other parameters, appeared useful for quantitative assessment of the disease: heterogeneity index values ranging 0.1-0.4 point to pronounced heterogeneity of epithelial cell nucleus surface and DNA level, and are suggestive of malignant transformation of tissue, whereas benign proliferation of the epithelium is usually characterized by 0.4 less than h less than or equal to 0.9.

Physical labeling of papillomavirus-infected, immortal, and cancerous cervical epithelial cells reveal surface changes at immortal stage.

PubMed

Swaminathan Iyer, K; Gaikwad, R M; Woodworth, C D; Volkov, D O; Sokolov, Igor

2012-06-01

A significant change of surface features of malignant cervical epithelial cells compared to normal cells has been previously reported. Here, we are studying the question at which progressive stage leading to cervical cancer the surface alteration happens. A non-traditional method to identify malignant cervical epithelial cells in vitro, which is based on physical (in contrast to specific biochemical) labelling of cells with fluorescent silica micron-size beads, is used here to examine cells at progressive stages leading to cervical cancer which include normal epithelial cells, cells infected with human papillomavirus type-16 (HPV-16), cells immortalized by HPV-16, and carcinoma cells. The study shows a statistically significant (at p < 0.01) difference between both immortal and cancer cells and a group consisting of normal and infected. There is no significant difference between normal and infected cells. Immortal cells demonstrate the signal which is closer to cancer cells than to either normal or infected cells. This implies that the cell surface, surface cellular brush changes substantially when cells become immortal. Physical labeling of the cell surface represents a substantial departure from the traditional biochemical labeling methods. The results presented show the potential significance of physical properties of the cell surface for development of clinical methods for early detection of cervical cancer, even at the stage of immortalized, premalignant cells.

Physical Labeling of Papillomavirus-Infected, Immortal, and Cancerous Cervical Epithelial Cells Reveal Surface Changes at Immortal Stage

PubMed Central

Iyer, K. Swaminathan; Gaikwad, R. M.; Woodworth, C. D.; Volkov, D. O.

2013-01-01

A significant change of surface features of malignant cervical epithelial cells compared to normal cells has been previously reported. Here, we are studying the question at which progressive stage leading to cervical cancer the surface alteration happens. A non-traditional method to identify malignant cervical epithelial cells in vitro, which is based on physical (in contrast to specific biochemical) labelling of cells with fluorescent silica micron-size beads, is used here to examine cells at progressive stages leading to cervical cancer which include normal epithelial cells, cells infected with human papillomavirus type-16 (HPV-16), cells immortalized by HPV-16, and carcinoma cells. The study shows a statistically significant (at p <0.01) difference between both immortal and cancer cells and a group consisting of normal and infected. There is no significant difference between normal and infected cells. Immortal cells demonstrate the signal which is closer to cancer cells than to either normal or infected cells. This implies that the cell surface, surface cellular brush changes substantially when cells become immortal. Physical labeling of the cell surface represents a substantial departure from the traditional biochemical labeling methods. The results presented show the potential significance of physical properties of the cell surface for development of clinical methods for early detection of cervical cancer, even at the stage of immortalized, pre-malignant cells. PMID:22351422

"You Want Us to Teach Outdoor Education Where?" Reflections on Teaching Outdoor Education Online

ERIC Educational Resources Information Center

Smith, H. A.; Dyment, J. E.; Hill, A.; Downing, J.

2016-01-01

This article reports on the experiences of two lecturers working at the University of Tasmania required to teach outdoor and sustainability education (O&SE) courses online. Using an (auto)ethnographic case-study approach, the lecturers were interviewed with a view to exploring their perceptions, challenges, ethical dilemmas, tensions,…

Observing System Forecast Experiments at the DAO

NASA Technical Reports Server (NTRS)

Atlas, Robert

2001-01-01

Since the advent of meteorological satellites in the 1960's, numerous experiments have been conducted in order to evaluate the impact of these and other data on atmospheric analysis and prediction. Such studies have included both OSE'S and OSSE's. The OSE's were conducted to evaluate the impact of specific observations or classes of observations on analyses and forecasts. Such experiments have been performed for selected types of conventional data and for various satellite data sets as they became available. (See for example the 1989 ECMWF/EUMETSAT workshop proceedings on "The use of satellite data in operational numerical weather prediction" and the references contained therein.) The ODYSSEY were conducted to evaluate the potential for future observing systems to improve Numerical Weather Prediction NWP and to plan for the Global Weather Experiment and more recently for EVANS (Atlas et al., 1985a; Arnold and Day, 1986; Hoffman et al., 1990). In addition, OSSE's have been run to evaluate trade-offs in the design of observing systems and observing networks (Atlas and Emmitt, 1991; Rohaly and Krishnamurti, 1993), and to test new methodology for data assimilation (Atlas and Bloom, 1989).

μSR investigation of magnetism and magnetoelectric coupling in Cu2OSeO3

NASA Astrophysics Data System (ADS)

Maisuradze, A.; Guguchia, Z.; Graneli, B.; Rønnow, H. M.; Berger, H.; Keller, H.

2011-08-01

A detailed zero- and transverse-field muon spin rotation investigation of magnetism and the magnetoelectric coupling in Cu2OSeO3 is reported. An internal magnetic field Bint(T=0)=85.37(25) mT was found, in agreement with a ferrimagnetic state below Tc=57.0(1) K. The temperature dependence of the magnetic order parameter is well described by the relation Bint=B(0)(1-(T/Tc)2)β˜ with an effective exponent β˜≃0.39(1), which is close to the critical exponent β≃1/3 for a three-dimensional (3D) magnetic system. Just above Tc the muon relaxation rate follows the power law λ(T)∝(T/Tc-1)-ω˜ with ω˜=1.06(9), which is characteristic for 3D ferromagnets. Measurements of Bint(T) with and without an applied electrostatic field E=1.66×105 V/m suggest a possible electric-field effect of magnitude ΔBV=BV(0V)-BV(500V)=-0.4(4) mT.

Strong Dzyaloshinskii-Moriya Interaction and Origin of Ferroelectricity in Cu2OSeO3

NASA Astrophysics Data System (ADS)

Yang, Ji-Hui; Li, Zheng-Lu; Lu, Xuezeng; Gong, X. G.; Xiang, Hongjun; Whangbo, M.-H.; Wei, Su-Huai

2013-03-01

In this work, we try to understand the skyrmions recently observed experimentally in Cu2OSeO3 system, as well as its origin of ferroelectricity. Based on the spin Hamiltonian, we developed four-state-energy-mapping method to derive these spin interaction parameters. For this system, we found a very large ratio between the DM term and the symmetric exchange interaction. Besides, the spin arrangements in the ground state are found degenerate and the spin energy is independent of the propagation vector q. Taking these two factors into account, we explained the experimental observation of skyrmions to some extent. Then we built a model to describe the polarization of this system. By the symmetry analysis, the ferroelectricity is supposed to result from the spin single-site term, as is confirmed by direct calculations of our model. Using this model, we analyzed its ferroelectricity dependence of the spin arrangement and find the largest polarization happens when the spins are along <111> direction, in excellent agreement with the experimental results. NSFC, Special Funds for Major State Basic Research, Pujiang plan, FANEDD

Global CLEWs model - A novel application of OSeMOSYS

NASA Astrophysics Data System (ADS)

Avgerinopoulos, Georgios; Pereira Ramos, Eunice; Howells, Mark

2017-04-01

Over the past years, studies that analyse Nexus issues from a holistic point of view and not energy, land or water separately have been gaining momentum. This project aims at giving insights into global issues through the application and the analysis of a global scale OSeMOSYS model. The latter -which is based on a fully open and amendable code- has been used successfully in the latest years as it has been the producing fully accessible energy models suitable for capacity building and policy making suggestions. This study develops a CLEWs (climate, land, energy and water) model with the objective of interrogating global challenges (e.g. increasing food demand) and international trade features, with policy priorities on food security, resource efficiency, low-carbon energy and climate change mitigation, water availability and vulnerability to water stress and floods, water quality, biodiversity and ecosystem services. It will for instance assess (i) the impact of water constraints on food security and human development (clean water for human use; industrial and energy water demands), as well as (ii) the impact of climate change on aggravating or relieving water problems.

Oxygen trapped by rare earth tetrahedral clusters in Nd4FeOS6: Crystal structure, electronic structure, and magnetic properties

NASA Astrophysics Data System (ADS)

Lin, Qisheng; Taufour, Valentin; Zhang, Yuemei; Wood, Max; Drtina, Thomas; Bud'ko, Sergey L.; Canfield, Paul C.; Miller, Gordon J.

2015-09-01

Single crystals of Nd4FeOS6 were grown from an Fe-S eutectic solution. Single crystal X-ray diffraction analysis revealed a Nd4MnOSe6-type structure (P63mc, a=9.2693(1) Å, c=6.6650(1)Å, V=495.94(1) Å3, Z=2), featuring parallel chains of face-sharing [FeS6×1/2]4- trigonal antiprisms and interlinked [Nd4OS3]4+ cubane-like clusters. Oxygen atoms were found to be trapped by Nd4 clusters in the [Nd4OS3]4+ chains. Structural differences among Nd4MnOSe6-type Nd4FeOS6 and the related La3CuSiS7- and Pr8CoGa3-type structures have been described. Magnetic susceptibility measurements on Nd4FeOS6 suggested the dominance of antiferromagnetic interactions at low temperature, but no magnetic ordering down to 2 K was observed. Spin-polarized electronic structure calculations revealed magnetic frustration with dominant antiferromagnetic interactions.

Neutrophil (PMN) surface contact with keratocytes following corneal epithelial abrasion in the mouse: a novel role for ICAM-1

USDA-ARS?s Scientific Manuscript database

Corneal epithelial abrasion is associated with an inflammatory response that involves PMN recruitment from the limbal vessels into the corneal stroma. Previously, in the injured mouse cornea, we showed that migrating PMNs not only make contact with collagen, but they also make extensive surface cont...

Mullerian papilloma-like proliferation arising in cystic pelvic endosalpingiosis.

PubMed

McCluggage, W Glenn; O'Rourke, Declan; McElhenney, Clodagh; Crooks, Michael

2002-09-01

This report describes an unusual epithelial proliferation occurring in pelvic cystic endosalpingiosis. A cyst mass lined by a layer of ciliated epithelial cells involved the posterior surface of the cervix and vagina. The epithelial proliferation within the wall resembled a mullerian papilloma with fibrous and fibrovascular cores lined by bland cuboidal epithelial cells. Other areas had a microglandular growth pattern resembling cervical microglandular hyperplasia, and focally there was a solid growth pattern. Foci of typical endosalpingiosis involved the surface of both ovaries and pelvic soft tissues. The cystic lesion recurred after partial cystectomy and drainage and was followed up radiologically and with periodic fine-needle aspiration. Part of the wall of the cyst removed 11 years after the original surgery showed an identical epithelial proliferation. MIB1 staining showed a proliferation index of less than 5%, contrasting with the higher proliferation index of a typical serous borderline tumor. The differential diagnosis is discussed. As far as we are aware, this is the first report of such a benign epithelial proliferation involving cystic endosalpingiosis. Copyright 2002, Elsevier Science (USA). All rights reserved.

Effects of voluntary running exercise on bone histology in type 2 diabetic rats.

PubMed

Takamine, Yuri; Ichinoseki-Sekine, Noriko; Tsuzuki, Takamasa; Yoshihara, Toshinori; Naito, Hisashi

2018-01-01

The incidence of obesity in children and adolescents, which may lead to type 2 diabetes, is increasing. Exercise is recommended to prevent and improve diabetes. However, little is known about the bone marrow environment at the onset of diabetes in the young, and it is unclear whether exercise training is useful for maintaining bone homeostasis, such as mechanical and histological properties. Thus, this study clarified the histological properties of bone and whether exercise contributes to maintaining bone homeostasis at the onset of type 2 diabetes in rats. Four-week-old male Otsuka Long-Evans Tokushima Fatty (OLETF; n = 21) rats as a diabetic model and Long-Evans Tokushima Otsuka (LETO; n = 18) rats as a control were assigned randomly to four groups: the OLETF sedentary group (O-Sed; n = 11), OLETF exercise group (O-Ex; n = 10), LETO sedentary group (L-Sed; n = 9), and LETO exercise group (L-Ex; n = 9). All rats in the exercise group were allowed free access to a steel running wheel for 20 weeks (5-25 weeks of age). In the glucose tolerance test, blood glucose level was higher in the O-Sed group than that in the L-Sed and L-Ex groups, and was markedly suppressed by the voluntary running exercise of O-Ex rats. The energy to fracture and the two-dimensional bone volume at 25 weeks of age did not differ significantly among the groups, though the maximum breaking force and stiffness were lower in OLETF rats. However, bone marrow fat volume was greater in O-Sed than that in L-Sed and L-Ex rats, and was markedly suppressed by wheel running in the O-Ex rats. Our results indicate that exercise has beneficial effects not only for preventing diabetes but also on normal bone remodeling at an early age.

Supporting New Missions by Observing Simulation Experiments in WACCM-X/GEOS-5 and TIME-GCM: Initial Design, Challenges and Perspectives

NASA Astrophysics Data System (ADS)

Yudin, V. A.; England, S.; Liu, H.; Solomon, S. C.; Immel, T. J.; Maute, A. I.; Burns, A. G.; Foster, B.; Wu, Q.; Goncharenko, L. P.

2013-12-01

We examine the capability of novel configurations of community models, WACCM-X and TIME-GCM, to support current and forthcoming space-borne missions to monitor the dynamics and composition of the Mesosphere-Thermosphere-Ionosphere (MTI) system. In these configurations the lower atmosphere of WACCM-X is constrained by operational analyses and/or short-term forecasts provided by the Goddard Earth Observing System (GEOS-5) of Global Modeling and Assimilation Office at NASA/GSFC. With the terrestrial weather of GEOS-5 and updated model physics the simulations in the MTI are capable to reproduce observed signatures of the perturbed wave dynamics and ion-neutral coupling during recent stratospheric warming events, short-term, annual and year-to-year variability of prevailing flows, planetary waves, tides, and composition. These 'terrestrial-weather' driven simulations with day-to-day variable solar and geomagnetic inputs can provide background state (first guess) and error statistics for the inverse algorithms of new NASA missions, ICON and GOLD at locations and time of observations in the MTI region. With two different viewing geometries (sun-synchronous and geostationary) of instruments, ICON and GOLD will provide complimentary global observations of temperature, winds and constituents to constrain the first-principle forecast models. This paper will discuss initial design of Observing Simulation Experiments (OSE) in WACCM-X/GEOS-5 and TIME-GCM. As recognized, OSE represent an excellent learning tool for designing and evaluating observing capabilities of novel sensors. They can guide on how to integrate/combine information from different instruments. The choice of assimilation schemes, forecast and observational errors will be discussed along with challenges and perspectives to constrain fast-varying tidal dynamics and their effects in models by combination of sun-synchronous and geostationary observations of ICON and GOLD. We will also discuss how correlative space-borne and ground-based observations can verify OSE results in the observable and non-observable regions of the MTI.

Volumetric imaging of oral epithelial neoplasia by MPM-SHGM: epithelial connective tissue interface (Conference Presentation)

NASA Astrophysics Data System (ADS)

Pal, Rahul; Yang, Jinping; Qiu, Suimin; Resto, Vicente; McCammon, Susan; Vargas, Gracie

2016-03-01

The majority of oral cancers are comprised of oral squamous cell carcinoma in which neoplastic epithelial cells invade across the epithelial connective tissue interface (ECTI). Invasion is preceded by a multi-component process including epithelial hyperproliferation, loss of cell polarity, and remodeling of the extracellular matrix. Multiphoton Autofluorescence Microscopy (MPAM) and Second Harmonic Generation Microscopy (SHGM) show promise for revealing indicators of neoplasia. In particular, volumetric imaging by these methods can reveal aspects of the 3D microstructure that are not possible by other methods and which could both further our understanding of neoplastic transformation and be explored for development of diagnostic approaches in this disease having only 55% 5-year survival rate. MPAM-SHG were applied to reveal the 3D structure of the critical ECTI interface that plays an integral part toward invasion. Epithelial dysplasia was induced in an established hamster model. MPAM-SHGM was applied to lesion sites, using 780 nm excitation (450-600nm emission) for autofluroescence of cellular and extracellular components; 840 nm using 420 nm bandpass filter for SHG. The ECTI surface was identified as the interface at which SHG signal began following the epithelium and was modeled as a 3D surface using Matlab. ECTI surface area and cell features at sites of epithelial expansion where ECTI was altered were measured; Imaged sites were biopsied and processed for histology. ROC analysis using ECTI image metrics indicated the ability to delineate normal from neoplasia with high sensitivity and specificity and it is noteworthy that inflammation did not significantly alter diagnostic potential of MPAM-SHGM .

Immunocytochemistry of cell surface heparan sulfate proteoglycan in mouse tissues. A light and electron microscopic study.

PubMed

Hayashi, K; Hayashi, M; Jalkanen, M; Firestone, J H; Trelstad, R L; Bernfield, M

1987-10-01

The core protein of the proteoglycan at the cell surface of NMuMG mouse mammary epithelial cells bears both heparan and chondroitin sulfate chains and is recognized by the monoclonal antibody 281-2. Using this antibody and the peroxidase-antiperoxidase staining technique in adult mouse tissues, we found that the antibody recognizes the antigen in a highly restricted distribution, staining a variety of epithelial cells but no cells derived from embryonic mesoderm or neural crest. The antibody fails to stain any stromal (mesenchymal) or neuronal cells, with the exception of plasma cells and Leydig cells. Squamous and transitional epithelia stain intensely over their entire surfaces, whereas cuboidal and columnar epithelia stain moderately and only at the lateral surface of the basal cells. Within squamous and transitional epithelial tissues that undergo physiological regeneration (e.g., epidermis), the most superficial and differentiated cell types fail to stain. Within glandular and branched epithelia (e.g., pancreas), the secretory alveolar cells fail to stain. When evaluated by electron microscopy, granular deposits of stain are seen on the plasma membrane, especially on lateral surfaces, but none are noted within the cells or the basement membrane. These results indicate that in adult tissues the core protein of this heparan sulfate-rich proteoglycan is expressed almost exclusively at epithelial cell surfaces. Expression appears to be lost as the cells become either mature or highly differentiated.

Collective cell behavior on basement membranes floating in space

NASA Astrophysics Data System (ADS)

Ellison, Sarah; Bhattacharjee, Tapomoy; Morley, Cameron; Sawyer, W.; Angelini, Thomas

The basement membrane is an essential part of the polarity of endothelial and epithelial tissues. In tissue culture and organ-on-chip devices, monolayer polarity can be established by coating flat surfaces with extracellular matrix proteins and tuning the trans-substrate permeability. In epithelial 3D culture, spheroids spontaneously establish inside-out polarity, morphing into hollow shell-like structures called acini, generating their own basement membrane on the inner radius of the shell. However, 3D culture approaches generally lack the high degree of control provided by the 2D culture plate or organ-on-chip devices, making it difficult to create more faithful in vitro tissue models with complex surface curvature and morphology. Here we present a method for 3D printing complex basement membranes covered in cells. We 3D print collagen-I and Matrigel into a 3D growth medium made from jammed microgels. This soft, yielding material allows extracellular matrix to be formed as complex surfaces and shapes, floating in space. We then distribute MCF10A epithelial cells across the polymerized surface. We envision employing this strategy to study 3D collective cell behavior in numerous model tissue layers, beyond this simple epithelial model.

High Speed Hazard Avoidance for Unmanned Ground Vehicles in Emergency Situations

DTIC Science & Technology

2006-11-01

xx κτ ,vnominal ≡ , where x designates the UGV osition in space. If a hazard detected by a range sensor oses a threat, the UGV enacts an...source of error is the calculation of the path curvature, which can be highly sensitive to the GPS and INS position estimates. 6.2. Validation of

Notes on phase transitions and the role of spin fluctuations

NASA Astrophysics Data System (ADS)

Stishov, S. M.

2016-09-01

The physical properties of two chiral systems with localized and delocalized magnetic moments, {\\text{Cu}}2{\\text{OSeO}}3 and MnSi, are reviewed. It is concluded that the longitudinal fluctuations of magnetic moments have no strong effect on the qualitative picture of phase transitions and the magnetic phase diagrams of chiral systems.

Migrations of the Mind: The Emergence of Open Source Education

ERIC Educational Resources Information Center

Glassman, Michael; Bartholomew, Mitchell; Jones, Travis

2011-01-01

The authors describe an Open Source approach to education. They define Open Source Education (OSE) as a teaching and learning framework where the use and presentation of information is non-hierarchical, malleable, and subject to the needs and contributions of students as they become "co-owners" of the course. The course transforms itself into an…

Rapid Ultrasonic Inspection of Artillery Projectiles.

DTIC Science & Technology

1978-05-01

R. B. Thompson, M. W. Mahoney DAAKIO-77-C-2020 S. PERFORMING ORGANIZATION NAMIE AND AOoRESS 10. PROGRAM ELEMENT. PROJECT,. TASK Rockwell...6M)5 .4A ! 7 )z .(A xOTz - TIO PROCESSOR APPROIMATE IME SCALE A SoIc a asoc 50 $sac 58 010C 100 oseK 0 pS Fig. 5 Time diagram of analog signal

Selumetinib Sulfate in Treating Woman With Recurrent Low-Grade Ovarian Cancer or Peritoneum Cancer

ClinicalTrials.gov

2018-03-30

Borderline Ovarian Epithelial Tumor; Low Grade Ovarian Serous Adenocarcinoma; Primary Peritoneal Carcinoma; Primary Peritoneal Low Grade Serous Adenocarcinoma; Recurrent Borderline Ovarian Surface Epithelial-Stromal Tumor

Interaction of galectin-3 with MUC1 on cell surface promotes EGFR dimerization and activation in human epithelial cancer cells.

PubMed

Piyush, Tushar; Chacko, Anisha R; Sindrewicz, Paulina; Hilkens, John; Rhodes, Jonathan M; Yu, Lu-Gang

2017-11-01

Epidermal growth factor receptor (EGFR) is an important regulator of epithelial cell growth and survival in normal and cancerous tissues and is a principal therapeutic target for cancer treatment. EGFR is associated in epithelial cells with the heavily glycosylated transmembrane mucin protein MUC1, a natural ligand of galectin-3 that is overexpressed in cancer. This study reveals that the expression of cell surface MUC1 is a critical enhancer of EGF-induced EGFR activation in human breast and colon cancer cells. Both the MUC1 extracellular and intracellular domains are involved in EGFR activation but the predominant influence comes from its extracellular domain. Binding of galectin-3 to the MUC1 extracellular domain induces MUC1 cell surface polarization and increases MUC1-EGFR association. This leads to a rapid increase of EGFR homo-/hetero-dimerization and subsequently increased, and also prolonged, EGFR activation and signalling. This effect requires both the galectin-3 C-terminal carbohydrate recognition domain and its N-terminal ligand multi-merization domain. Thus, interaction of galectin-3 with MUC1 on cell surface promotes EGFR dimerization and activation in epithelial cancer cells. As MUC1 and galectin-3 are both commonly overexpressed in most types of epithelial cancers, their interaction and impact on EGFR activation likely makes important contribution to EGFR-associated tumorigenesis and cancer progression and may also influence the effectiveness of EGFR-targeted cancer therapy.

Surface contamination analysis technology team overview

NASA Technical Reports Server (NTRS)

Burns, H. Dewitt

1995-01-01

A team was established which consisted of representatives from NASA (Marshall Space Flight Center and Langley Research Center), Thiokol Corporation, the University of Alabama in Huntsville, AC Engineering, SAIC, Martin Marietta, and Aerojet. The team's purpose was to bring together the appropriate personnel to determine what surface inspection techniques were applicable to multiprogram bonding surface cleanliness inspection. In order to identify appropriate techniques and their sensitivity to various contaminant families, calibration standards were developed. Producing standards included development of consistent low level contamination application techniques. Oxidation was also considered for effect on inspection equipment response. Ellipsometry was used for oxidation characterization. Verification testing was then accomplished to show that selected inspection techniques could detect subject contaminants at levels found to be detrimental to critical bond systems of interest. Once feasibility of identified techniques was shown, selected techniques and instrumentation could then be incorporated into a multipurpose inspection head and integrated with a robot for critical surface inspection. Inspection techniques currently being evaluated include optically stimulated electron emission (OSEE); near infrared (NIR) spectroscopy utilizing fiber optics; Fourier transform infrared (FTIR) spectroscopy; and ultraviolet (UV) fluorescence. Current plans are to demonstrate an integrated system in MSFC's Productivity Enhancement Complex within five years from initiation of this effort in 1992 assuming appropriate funding levels are maintained. This paper gives an overview of work accomplished by the team and future plans.

In Vivo Epithelial Wound Repair Requires Mobilization of Endogenous Intracellular and Extracellular Calcium*

PubMed Central

Aihara, Eitaro; Hentz, Courtney L.; Korman, Abraham M.; Perry, Nicholas P. J.; Prasad, Vikram; Shull, Gary E.; Montrose, Marshall H.

2013-01-01

We report that a localized intracellular and extracellular Ca2+ mobilization occurs at the site of microscopic epithelial damage in vivo and is required to mediate tissue repair. Intravital confocal/two-photon microscopy continuously imaged the surgically exposed stomach mucosa of anesthetized mice while photodamage of gastric epithelial surface cells created a microscopic lesion that healed within 15 min. Transgenic mice with an intracellular Ca2+-sensitive protein (yellow cameleon 3.0) report that intracellular Ca2+ selectively increases in restituting gastric epithelial cells adjacent to the damaged cells. Pretreatment with U-73122, indomethacin, 2-aminoethoxydiphenylborane, or verapamil inhibits repair of the damage and also inhibits the intracellular Ca2+ increase. Confocal imaging of Fura-Red dye in luminal superfusate shows a localized extracellular Ca2+ increase at the gastric surface adjacent to the damage that temporally follows intracellular Ca2+ mobilization. Indomethacin and verapamil also inhibit the luminal Ca2+ increase. Intracellular Ca2+ chelation (1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid/acetoxymethyl ester, BAPTA/AM) fully inhibits intracellular and luminal Ca2+ increases, whereas luminal calcium chelation (N-(2-hydroxyetheyl)-ethylendiamin-N,N,N′-triacetic acid trisodium, HEDTA) blocks the increase of luminal Ca2+ and unevenly inhibits late-phase intracellular Ca2+ mobilization. Both modes of Ca2+ chelation slow gastric repair. In plasma membrane Ca-ATPase 1+/− mice, but not plasma membrane Ca-ATPase 4−/− mice, there is slowed epithelial repair and a diminished gastric surface Ca2+ increase. We conclude that endogenous Ca2+, mobilized by signaling pathways and transmembrane Ca2+ transport, causes increased Ca2+ levels at the epithelial damage site that are essential to gastric epithelial cell restitution in vivo. PMID:24121509

In vivo epithelial wound repair requires mobilization of endogenous intracellular and extracellular calcium.

PubMed

Aihara, Eitaro; Hentz, Courtney L; Korman, Abraham M; Perry, Nicholas P J; Prasad, Vikram; Shull, Gary E; Montrose, Marshall H

2013-11-22

We report that a localized intracellular and extracellular Ca(2+) mobilization occurs at the site of microscopic epithelial damage in vivo and is required to mediate tissue repair. Intravital confocal/two-photon microscopy continuously imaged the surgically exposed stomach mucosa of anesthetized mice while photodamage of gastric epithelial surface cells created a microscopic lesion that healed within 15 min. Transgenic mice with an intracellular Ca(2+)-sensitive protein (yellow cameleon 3.0) report that intracellular Ca(2+) selectively increases in restituting gastric epithelial cells adjacent to the damaged cells. Pretreatment with U-73122, indomethacin, 2-aminoethoxydiphenylborane, or verapamil inhibits repair of the damage and also inhibits the intracellular Ca(2+) increase. Confocal imaging of Fura-Red dye in luminal superfusate shows a localized extracellular Ca(2+) increase at the gastric surface adjacent to the damage that temporally follows intracellular Ca(2+) mobilization. Indomethacin and verapamil also inhibit the luminal Ca(2+) increase. Intracellular Ca(2+) chelation (1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/acetoxymethyl ester, BAPTA/AM) fully inhibits intracellular and luminal Ca(2+) increases, whereas luminal calcium chelation (N-(2-hydroxyetheyl)-ethylendiamin-N,N,N'-triacetic acid trisodium, HEDTA) blocks the increase of luminal Ca(2+) and unevenly inhibits late-phase intracellular Ca(2+) mobilization. Both modes of Ca(2+) chelation slow gastric repair. In plasma membrane Ca-ATPase 1(+/-) mice, but not plasma membrane Ca-ATPase 4(-/-) mice, there is slowed epithelial repair and a diminished gastric surface Ca(2+) increase. We conclude that endogenous Ca(2+), mobilized by signaling pathways and transmembrane Ca(2+) transport, causes increased Ca(2+) levels at the epithelial damage site that are essential to gastric epithelial cell restitution in vivo.

Nasal Epithelial Cells as Surrogates for Bronchial Epithelial Cells in Airway Inflammation Studies

PubMed Central

McDougall, Catherine M.; Blaylock, Morgan G.; Douglas, J. Graham; Brooker, Richard J.; Helms, Peter J.; Walsh, Garry M.

2008-01-01

The nose is an attractive source of airway epithelial cells, particularly in populations in which bronchoscopy may not be possible. However, substituting nasal cells for bronchial epithelial cells in the study of airway inflammation depends upon comparability of responses, and evidence for this is lacking. Our objective was to determine whether nasal epithelial cell inflammatory mediator release and receptor expression reflect those of bronchial epithelial cells. Paired cultures of undifferentiated nasal and bronchial epithelial cells were obtained from brushings from 35 subjects, including 5 children. Cells were subject to morphologic and immunocytochemical assessment. Mediator release from resting and cytokine-stimulated cell monolayers was determined, as was cell surface receptor expression. Nasal and bronchial cells had identical epithelial morphology and uniform expression of cytokeratin 19. There were no differences in constitutive expression of CD44, intercellular adhesion molecule-1, αvβ3, and αvβ5. Despite significantly higher constitutive release of IL-8, IL-6, RANTES (regulated on activation, normal T cell expressed and secreted), and matrix metalloproteinase (MMP)-9 from nasal compared with bronchial cells, the increments in release of all studied mediators in response to stimulation with IL-1β and TNF-α were similar, and there were significant positive correlations between nasal and bronchial cell secretion of IL-6, RANTES, vascular endothelial growth factor, monocyte chemoattractant protein-1, MMP-9, and tissue inhibitor of metalloproteinase-1. Despite differences in absolute mediator levels, the responses of nasal and bronchial epithelial cells to cytokine stimulation were similar, expression of relevant surface receptors was comparable, and there were significant correlations between nasal and bronchial cell mediator release. Therefore, nasal epithelial cultures constitute an accessible surrogate for studying lower airway inflammation. PMID:18483420

Nasal epithelial cells as surrogates for bronchial epithelial cells in airway inflammation studies.

PubMed

McDougall, Catherine M; Blaylock, Morgan G; Douglas, J Graham; Brooker, Richard J; Helms, Peter J; Walsh, Garry M

2008-11-01

The nose is an attractive source of airway epithelial cells, particularly in populations in which bronchoscopy may not be possible. However, substituting nasal cells for bronchial epithelial cells in the study of airway inflammation depends upon comparability of responses, and evidence for this is lacking. Our objective was to determine whether nasal epithelial cell inflammatory mediator release and receptor expression reflect those of bronchial epithelial cells. Paired cultures of undifferentiated nasal and bronchial epithelial cells were obtained from brushings from 35 subjects, including 5 children. Cells were subject to morphologic and immunocytochemical assessment. Mediator release from resting and cytokine-stimulated cell monolayers was determined, as was cell surface receptor expression. Nasal and bronchial cells had identical epithelial morphology and uniform expression of cytokeratin 19. There were no differences in constitutive expression of CD44, intercellular adhesion molecule-1, alphavbeta3, and alphavbeta5. Despite significantly higher constitutive release of IL-8, IL-6, RANTES (regulated on activation, normal T cell expressed and secreted), and matrix metalloproteinase (MMP)-9 from nasal compared with bronchial cells, the increments in release of all studied mediators in response to stimulation with IL-1beta and TNF-alpha were similar, and there were significant positive correlations between nasal and bronchial cell secretion of IL-6, RANTES, vascular endothelial growth factor, monocyte chemoattractant protein-1, MMP-9, and tissue inhibitor of metalloproteinase-1. Despite differences in absolute mediator levels, the responses of nasal and bronchial epithelial cells to cytokine stimulation were similar, expression of relevant surface receptors was comparable, and there were significant correlations between nasal and bronchial cell mediator release. Therefore, nasal epithelial cultures constitute an accessible surrogate for studying lower airway inflammation.

Regulation of epithelial and lymphocyte cell adhesion by adenosine deaminase-CD26 interaction.

PubMed Central

Ginés, Silvia; Mariño, Marta; Mallol, Josefa; Canela, Enric I; Morimoto, Chikao; Callebaut, Christian; Hovanessian, Ara; Casadó, Vicent; Lluis, Carmen; Franco, Rafael

2002-01-01

The extra-enzymic function of cell-surface adenosine deaminase (ADA), an enzyme mainly localized in the cytosol but also found on the cell surface of monocytes, B cells and T cells, has lately been the subject of numerous studies. Cell-surface ADA is able to transduce co-stimulatory signals in T cells via its interaction with CD26, an integral membrane protein that acts as ADA-binding protein. The aim of the present study was to explore whether ADA-CD26 interaction plays a role in the adhesion of lymphocyte cells to human epithelial cells. To meet this aim, different lymphocyte cell lines (Jurkat and CEM T) expressing endogenous, or overexpressing human, CD26 protein were tested in adhesion assays to monolayers of colon adenocarcinoma human epithelial cells, Caco-2, which express high levels of cell-surface ADA. Interestingly, the adhesion of Jurkat and CEM T cells to a monolayer of Caco-2 cells was greatly dependent on CD26. An increase by 50% in the cell-to-cell adhesion was found in cells containing higher levels of CD26. Incubation with an anti-CD26 antibody raised against the ADA-binding site or with exogenous ADA resulted in a significant reduction (50-70%) of T-cell adhesion to monolayers of epithelial cells. The role of ADA-CD26 interaction in the lymphocyte-epithelial cell adhesion appears to be mediated by CD26 molecules that are not interacting with endogenous ADA (ADA-free CD26), since SKW6.4 (B cells) that express more cell-surface ADA showed lower adhesion than T cells. Adhesion stimulated by CD26 and ADA is mediated by T cell lymphocyte function-associated antigen. A role for ADA-CD26 interaction in cell-to-cell adhesion was confirmed further in integrin activation assays. FACS analysis revealed a higher expression of activated integrins on T cell lines in the presence of increasing amounts of exogenous ADA. Taken together, these results suggest that the ADA-CD26 interaction on the cell surface has a role in lymphocyte-epithelial cell adhesion. PMID:11772392

Neisseria gonorrhoeae infects the human endocervix by activating non-muscle myosin II-mediated epithelial exfoliation

PubMed Central

Yu, Qian; Lin, Brian; Qiu, Jessica; Stein, Daniel C.

2017-01-01

Colonization and disruption of the epithelium is a major infection mechanism of mucosal pathogens. The epithelium counteracts infection by exfoliating damaged cells while maintaining the mucosal barrier function. The sexually transmitted bacterium Neisseria gonorrhoeae (GC) infects the female reproductive tract primarily from the endocervix, causing gonorrhea. However, the mechanism by which GC overcome the mucosal barrier remains elusive. Using a new human tissue model, we demonstrate that GC can penetrate into the human endocervix by inducing the exfoliation of columnar epithelial cells. We found that GC colonization causes endocervical epithelial cells to shed. The shedding results from the disassembly of the apical junctions that seal the epithelial barrier. Apical junction disruption and epithelial exfoliation increase GC penetration into the endocervical epithelium without reducing bacterial adherence to and invasion into epithelial cells. Both epithelial exfoliation and junction disruption require the activation and accumulation of non-muscle myosin II (NMII) at the apical surface and GC adherent sites. GC inoculation activates NMII by elevating the levels of the cytoplasmic Ca2+ and NMII regulatory light chain phosphorylation. Piliation of GC promotes, but the expression of a GC opacity-associated protein variant, OpaH that binds to the host surface proteins CEACAMs, inhibits GC-induced NMII activation and reorganization and Ca2+ flux. The inhibitory effects of OpaH lead to reductions in junction disruption, epithelial exfoliation, and GC penetration. Therefore, GC phase variation can modulate infection in the human endocervix by manipulating the activity of NMII and epithelial exfoliation. PMID:28406994

The fate of epithelial cells in the human large intestine.

PubMed

Barkla, D H; Gibson, P R

1999-08-01

One hundred and forty biopsies of the colon and rectum, collected during routine colonoscopies of 51 patients aged 19 to 74 years, were examined using light microscopy and transmission and scanning electron microscopy. The results indicated that surface epithelial cells undergo apoptosis, passing through fenestrations in the basement membrane to where they enter the lamina propria and are taken up by macrophages; and it is hypothesized that apoptotic cells are carried through the fenestrations on a current of fluid. The study also found that epithelial cells positioned over the crypts are better attached and more robust than those more distant from the crypt opening; and it is further hypothesized that, after reaching the top of the crypts, some goblet cells cease secreting mucus and pass onto the surface compartment of absorptive cells. An unexpected finding was that the lower regions of the crypts commonly contain isolated necrotic colonocytes. Apoptotic cells were rarely observed in the crypt epithelium. The findings of this study support the "recycling" model of epithelial cell death in the surface compartment of the human colon.

The Corneal Epithelial Barrier and Its Developmental Role in Isolating Corneal Epithelial and Conjunctival Cells From One Another

PubMed Central

Kubilus, James K.; Zapater i Morales, Carolina; Linsenmayer, Thomas F.

2017-01-01

Purpose During development, the corneal epithelium (CE) and the conjunctiva are derived from the surface ectoderm. Here we have examined how, during development, the cells of these two issues become isolated from each other. Methods Epithelia from the anterior eyes of chicken embryos were labeled with the fluorescent, lipophilic dye, 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI). DiI was placed on the epithelial surface of the developing anterior eye and its diffusion was monitored by fluorescence microscopy. Concomitant morphologic changes in the surface cells of these epithelial were examined by scanning electron microscopy. Immunofluorescence was used to analyze the expression of cytokeratin K3, ZO-1, N-cadherin and Connexin-43 and the function of gap junctions was analyzed using a cut-loading with the fluorescent dye rhodamine-dextran. Results Prior to embryonic day 8 (E8), DiI placed on the surface of the CE spreads throughout all the epithelial cells of the anterior eye. When older eyes were similarly labeled, dye diffusion was restricted to the CE. Similarly, diffusion of DiI placed on the conjunctival surface after E8 was restricted to the conjunctiva. Scanning electron microscopy showed that developmentally (1) physical separations progressively form between the cells of the CE and those of the conjunctiva, and (2) by E8 these separations form a ring that completely encompasses the cornea. The functional restriction of gap junctions between these tissues did not occur until E14. Conclusions During ocular development, a barrier to the diffusion of DiI forms between the contiguous CE and conjunctiva prior to the differential expression of gap junctions within these tissues. PMID:28319640

Transepithelial phototherapeutic keratectomy protocol for treating irregular astigmatism based on population epithelial thickness measurements by artemis very high-frequency digital ultrasound.

PubMed

Reinstein, Dan Z; Archer, Timothy J; Dickeson, Zachary I; Gobbe, Marine

2014-06-01

To report the outcomes of transepithelial phototherapeutic keratectomy (TE-PTK) in the treatment of irregular astigmatism and define a standard treatment protocol based on population epithelial thickness measurements. Retrospective analysis of 41 TE-PTK procedures in cases of irregular astigmatism after refractive surgery or with corneal irregularities. The TE-PTK ablations were performed according to preoperative epithelial thickness maps obtained using an Artemis very high-frequency digital ultrasound arc-scanner (ArcScan, Inc., Morrison, CO). Visual and refractive outcomes were analyzed 12 months after the procedure. The efficacy of the stromal surface regularization was evaluated as the change in epithelial thickness range (ie, the difference between minimum and maximum epithelial thickness). A further refractive ablation was performed immediately after TE-PTK in 12 eyes. Corrected distance visual acuity was improved by one or more lines in 58% of eyes, whereas 1 eye lost one line and no eyes lost two lines. Significant stromal surface regularization was achieved with epithelial thickness range reduced on average from 41 to 29 μm. There was an unpredictable refractive shift in the TE-PTK only group with a change of more than 0.50 diopter (D) in 59% of eyes. Refractive accuracy in the TE-PTK with refractive ablation group was reasonably good, although there were two outliers (18%) outside ±1.00 D. A therapeutic window was identified between the highest thinnest epithelium of 51 μm and lowest thickest epithelium of 60 μm. TE-PTK can be a safe and effective method of reducing stromal surface irregularities by taking advantage of the natural masking effect of the epithelium. There can be a significant refractive shift due to lenticular epithelial masking. A standard protocol of targeting an initial TE-PTK ablation for 55 μm will likely achieve breakthrough of the thinnest epithelium without total epithelial removal, allowing the treatment to be continued in a stepwise fashion. Copyright 2014, SLACK Incorporated.

Evaluation of Common Angling-Induced Sources of Epithelial Damage for Popular Freshwater Sport Fish using Fluorescein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colotelo, Alison HA; Cooke, Steven J.

Angling is a popular recreational activity across the globe and a large proportion of fish captured by anglers are released due to voluntary or mandatory catch-and-release practices. The handling associated with hook removal and return of the fish to their environment can cause physical damage to the epidermal layer of the fish which may affect the condition and survival of released fish. This study investigated possible sources of epithelial damage associated with several different handling methods (i.e. landing net types, interactions with different boat floor surfaces, tournament procedures) commonly used in recreational angling for two popular freshwater sport fish species,more » largemouth bass (Micropterus salmoides) and northern pike (Esox lucius). Epithelial damage was examined using fluorescein, a non-toxic dye, which has been shown to detect latent epithelial damage. Northern pike exhibited extensive epithelial damage after exposure to several of the induced treatments (i.e., interaction with a carpeted surface, knotted nylon net, and line rolling) but relatively little epithelial damage when exposed to others (i.e., knotless rubber nets, smooth boat surfaces, or lip gripping devices). Largemouth bass did not show significant epithelial damage for any of the treatments, with the exception of fish caught in a semi-professional live release tournament. The detection of latent injuries using fluorescein can be an important management tool as it provides visual examples of potential damage that can be caused by different handling methods. Such visualizations can be used to encourage fish friendly angler behaviour and enhance the survival and welfare of released fish. It can also be used to test new products that are intended to or claim to reduce injury to fish that are to be released. Future research should evaluate the relationship between different levels of epithelial damage and mortality across a range of environmental conditions.« less

Commanding and Controlling Satellite Clusters (IEEE Intelligent Systems, November/December 2000)

DTIC Science & Technology

2000-01-01

real - time operating system , a message-passing OS well suited for distributed...ground Flight processors ObjectAgent RTOS SCL RTOS RDMS Space command language Real - time operating system Rational database management system TS-21 RDMS...engineer with Princeton Satellite Systems. She is working with others to develop ObjectAgent software to run on the OSE Real Time Operating System .

77 FR 20688 - 29th Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-05

.... SC-206 Related Work in SESAR--Progress Status. Discuss previously proposed TOR changes and DO-252 Revision. [cir] Discuss TOR changes for the June PMC meeting. PMC decision on OSED document. ConUse FRAC... dates. Decision to approve the ConUse document for release to the PMC. Agree upon TOR changes for June...

Analysis Components Investigation Report

DTIC Science & Technology

2014-10-01

2013-08-13 UNCL ISSUE DATE: NNOT BE DISC ocuments ions, people sier to find the possibi lecting his d for re-ran ful to anno terms to f e analyst s...the valu to get the a Map in J alue. st of term ors, but on term, c f 22 ATION roviding osed of ginning, ssible to rom the and as In order

77 FR 58210 - 31st Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-19

... approve meeting agenda Action item review Sub-Group (SG1--Wake OSED, SG3--Architecture, SG4--DO-252... Architecture(s) AAtS Implementation Guidance Document New Capabilities in Flight Services 1 p.m. Opening... Action item review Future meeting plans and dates Other business 1 p.m. Adjourn (no lunch break) Welcome...

A unified approach for debugging is-a structure and mappings in networked taxonomies

PubMed Central

2013-01-01

Background With the increased use of ontologies and ontology mappings in semantically-enabled applications such as ontology-based search and data integration, the issue of detecting and repairing defects in ontologies and ontology mappings has become increasingly important. These defects can lead to wrong or incomplete results for the applications. Results We propose a unified framework for debugging the is-a structure of and mappings between taxonomies, the most used kind of ontologies. We present theory and algorithms as well as an implemented system RepOSE, that supports a domain expert in detecting and repairing missing and wrong is-a relations and mappings. We also discuss two experiments performed by domain experts: an experiment on the Anatomy ontologies from the Ontology Alignment Evaluation Initiative, and a debugging session for the Swedish National Food Agency. Conclusions Semantically-enabled applications need high quality ontologies and ontology mappings. One key aspect is the detection and removal of defects in the ontologies and ontology mappings. Our system RepOSE provides an environment that supports domain experts to deal with this issue. We have shown the usefulness of the approach in two experiments by detecting and repairing circa 200 and 30 defects, respectively. PMID:23548155

Identification of a major sialoprotein in the glycocalyx of human visceral glomerular epithelial cells.

PubMed Central

Kerjaschki, D; Poczewski, H; Dekan, G; Horvat, R; Balzar, E; Kraft, N; Atkins, R C

1986-01-01

Glomerular visceral epithelial cells are endowed with a sialic acid-rich surface coat (the "glomerular epithelial polyanion"), which in rat tissue contains the sialoprotein podocalyxin. We have identified a major membrane sialoprotein in human glomeruli that is similar to rat podocalyxin in its sialic acid-dependent binding of wheat germ agglutinin and in its localization on the surface of glomerular epithelial and endothelial cells, as shown by immunoelectron microscopy, using the monoclonal antibody PHM5. Differences in the sialoproteins of the two species are indicated by the discrepancy of their apparent molecular weights in sodium dodecyl sulfate gels, by the lack of cross reactivity of their specific antibodies, and by the lack of homology of their proteolytic peptide maps. It is therefore possible that the human glomerular sialoprotein and rat podocalyxin are evolutionarily distinct, but have similar functions. Images PMID:3533998

Emergence of an apical epithelial cell surface in vivo

PubMed Central

Sedzinski, Jakub; Hannezo, Edouard; Tu, Fan; Biro, Maté; Wallingford, John B.

2016-01-01

Epithelial sheets are crucial components of all metazoan animals, enclosing organs and protecting the animal from its environment. Epithelial homeostasis poses unique challenges, as addition of new cells and loss of old cells must be achieved without disrupting the fluid-tight barrier and apicobasal polarity of the epithelium. Several studies have identified cell biological mechanisms underlying extrusion of cells from epithelia, but far less is known of the converse mechanism by which new cells are added. Here, we combine molecular, pharmacological and laser-dissection experiments with theoretical modelling to characterize forces driving emergence of an apical surface as single nascent cells are added to a vertebrate epithelium in vivo. We find that this process involves the interplay between cell-autonomous actin-generated pushing forces in the emerging cell and mechanical properties of neighboring cells. Our findings define the forces driving this cell behavior, contributing to a more comprehensive understanding of epithelial homeostasis. PMID:26766441

CD44 staining of cancer stem-like cells is influenced by down-regulation of CD44 variant isoforms and up-regulation of the standard CD44 isoform in the population of cells that have undergone epithelial-to-mesenchymal transition.

PubMed

Biddle, Adrian; Gammon, Luke; Fazil, Bilal; Mackenzie, Ian C

2013-01-01

CD44 is commonly used as a cell surface marker of cancer stem-like cells in epithelial tumours, and we have previously demonstrated the existence of two different CD44(high) cancer stem-like cell populations in squamous cell carcinoma, one having undergone epithelial-to-mesenchymal transition and the other maintaining an epithelial phenotype. Alternative splicing of CD44 variant exons generates a great many isoforms, and it is not known which isoforms are expressed on the surface of the two different cancer stem-like cell phenotypes. Here, we demonstrate that cancer stem-like cells with an epithelial phenotype predominantly express isoforms containing the variant exons, whereas the cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition down-regulate these variant isoforms and up-regulate expression of the standard CD44 isoform that contains no variant exons. In addition, we find that enzymatic treatments used to dissociate cells from tissue culture or fresh tumour specimens cause destruction of variant CD44 isoforms at the cell surface whereas expression of the standard CD44 isoform is preserved. This results in enrichment within the CD44(high) population of cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition and depletion from the CD44(high) population of cancer stem-like cells that maintain an epithelial phenotype, and therefore greatly effects the characteristics of any cancer stem-like cell population isolated based on expression of CD44. As well as effecting the CD44(high) population, enzymatic treatment also reduces the percentage of the total epithelial cancer cell population staining CD44-positive, with potential implications for studies that aim to use CD44-positive staining as a prognostic indicator. Analyses of the properties of cancer stem-like cells are largely dependent on the ability to accurately identify and assay these populations. It is therefore critical that consideration be given to use of multiple cancer stem-like cell markers and suitable procedures for cell isolation in order that the correct populations are assayed.

Effect of respiratory syncytial virus (RSV) infection on the adherence of pathogenic bacteria to human epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faden, H.; Hong, J.J.; Ogra, P.L.

1986-03-01

The effect of RSV infection on the adherence of Streptococcus pneumoniae (SP), Haemophilus influenzae (HI) and Staphylococcus aureus (SA) to human epithelial cells was determined. RSV-infected Hep-2 cell cultures at different stages of expression of surface viral antigens and bacteria labeled with /sup 3/H-thymidine were employed to examine the kinetics of bacterial adherence to virus-infected cells. RSV infection did not alter the magnitude of adherence of HI or SA to HEp-2 cells. However, adherence of SP to HEp-2 cells was significantly (P < 0.01) enhanced by prior RSV infection. The degree of adherence was directly related to the amount ofmore » viral antigen expressed on the cell surface. The adherence was temperature dependent, with maximal adherence observed at 37/sup 0/C. Heat-inactivation of SP did not alter adherence characteristics. These data suggest that RSV infection increases adherence of SP to the surface of epithelial cells in vitro. Since attachment of bacteria to mucosal surfaces is the first step in many infections, it is suggested that viral infections of epithelial cells render them more susceptible to bacterial adherence. Thus, RSV infection in vivo may predispose children to SP infections, such as in otitis media, by increasing colonization with SP.« less

Expression and cytokine regulation of immune recognition elements by normal human biliary epithelial and established liver cell lines in vitro.

PubMed

Cruickshank, S M; Southgate, J; Selby, P J; Trejdosiewicz, L K

1998-10-01

Biliary epithelial cells are targets of immune-mediated attack in conditions such as primary biliary cirrhosis and allograft rejection. This has been attributed to the ability of biliary epithelial cells to express ligands for T cell receptors. We aimed to investigate the expression of immune recognition elements and the effects of pro-inflammatory and anti-inflammatory cytokines on cell surface phenotypes of normal human biliary epithelial cells and established human liver-derived (PLC/PRF/5, HepG2, Hep3B and CC-SW) lines. Cells were cultured in the presence or absence of cytokines for 72 h, and expression of cell surface molecules was assessed by flow cytometry and immunofluorescence. All cell lines expressed MHC class I, ICAM-1 (CD54), LFA-3 (CD58) and EGF receptor, and all but Hep3B expressed Fas/Apo-1 (CD95). Unlike hepatocyte-derived cell lines, biliary epithelial cells and CC-SW expressed CD40 and CD44. As expected, IFNgamma and TNFalpha upregulated expression of ICAM-1, MHC class I and MHC class II, particularly in biliary epithelial cells. TGFbeta downregulated these molecules and downregulated CD95 on biliary epithelial cells, but upregulated LFA-3. The Th2 cytokines had little effect, although IL-4 upregulated CD95 expression on biliary epithelial cells. IFNgamma upregulated CD40 expression on biliary epithelial cells, CC-SW and HepG2. These findings imply that biliary epithelial cells may be capable of interacting with activated T lymphocytes via CD40 and LFA-3, which are thought to be important T cell accessory ligands for T cell activation in a B7-independent manner. Sensitivity to pro-inflammatory cytokines and expression of CD95 may explain why biliary epithelial cells are primary targets for autoimmune attack.

Inhibition of experimental ascending urinary tract infection by an epithelial cell-surface receptor analogue

NASA Astrophysics Data System (ADS)

Edén, C. Svanborg; Freter, R.; Hagberg, L.; Hull, R.; Hull, S.; Leffler, H.; Schoolnik, G.

1982-08-01

It has been shown that the establishment of urinary tract infection by Escherichia coli is dependent on attachment of the bacteria to epithelial cells1-4. The attachment involves specific epithelial cell receptors, which have been characterized as glycolipids5-10. Reversible binding to cell-surface mannosides may also be important4,11-13. This suggests an approach to the treatment of infections-that of blocking bacterial attachment with cell membrane receptor analogues. Using E. coli mutants lacking one or other of the two binding specificities (glycolipid and mannose), we show here that glycolipid analogues can block in vitro adhesion and in vivo urinary tract infection.

An ultrastructural analysis of the epithelial-fiber interface (EFI) in primate lenses.

PubMed

Kuszak, J R; Novak, L A; Brown, H G

1995-11-01

The purpose of this study was to conduct a comprehensive ultrastructural analysis of the epithelial-fiber interface (EFI) in normal adult primate (Macaque nemestrina and fascicularis; 6-9 years old, n = 10) lenses. Scanning electron microscopy (SEM) was used to initially characterize the gross size, shape and three-dimensional organization of central zone (cz) epithelial cells and the anterior ends of elongating fibers beneath these cells. This fiducial information was essential to properly orient lens pieces in freeze fracture specimen carriers for the production of replicas with unambiguously identifiable EFI. Transmission electron microscopy (TEM) of replicas and thin-sectioned material were used to ultrastructurally analyse the cz EFI. TEM thin-sectioned material was also used to ultrastructurally analyse the pregerminative (pgz), germinative (gz) and transitional zone (tz) EFI. Correlative SEM and TEM of cz EFI components revealed that the apical membrane of both epithelial and elongating fiber cells were irregularly polygonal in shape, and aligned in parallel as smooth, concave-convex surfaces. However, whereas epithelial cell apical surfaces had minimal size variation, elongating fibers were larger and considerably variable in size. Quantitative analysis of > 10000 micron2 cz elongating fiber apical surfaces failed to detect any gap junctions defined in freeze fracture replicas as complementary aggregates of transmembrane proteins (connexons) conjoined across a narrowed extracellular space. However, a comparable frequency of vesicular events was noted in this region as quantified previously in adult and embryonic chick lens. Correlative TEM analysis > 1500 linear micrometers of thin-sectioned EFI from this region confirmed the presence of epithelial-epithelial gap junctions, elongating fiber-elongating fiber gap junctions, and an extreme paucity of epithelial-elongating fiber gap junctions. In contrast, TEM analysis of > 1000 linear micrometers of thin-sectioned pgz, gz and tz EFI, confirmed the presence of epithelial-epithelial gap junctions, elongating fiber-elongating fiber gap junctions, numerous epithelial-elongating fiber adherens junctions and a few epithelial-elongating fiber gap junctions. Thus, the results of this and previous quantitative morphological and physiological studies (electronic and dye coupling) demonstrate that there is limited coupling between cz epithelial cells and underlying elongating fibers. Furthermore, the absence of gap junctional plaques in cz EFI freeze-fracture replicas and either pentalaminar or septalaminar profiles in correlative thin-sections, suggests that this limited coupling could be mediated via isolated gap junction channels. However, the results of this and previous quantitative studies further show that a greater degree of coupling exists across the pgz, gz and tz regions of the EFI and that this coupling is likely to be mediated by gap junction plaques. Finally, this and other studies continue to demonstrate that transcytotic processes play a role in lens physiology at the EFI.

Expression of nestin, mesothelin and epithelial membrane antigen (EMA) in developing and adult human meninges and meningiomas.

PubMed

Petricevic, Josko; Forempoher, Gea; Ostojic, Ljerka; Mardesic-Brakus, Snjezana; Andjelinovic, Simun; Vukojevic, Katarina; Saraga-Babic, Mirna

2011-11-01

The spatial and temporal pattern of appearance of nestin, epithelial membrane antigen (EMA) and mesothelin proteins was immunohistochemically determined in the cells of normal developing and adult human meninges and meningiomas. Human meninges developed as two mesenchymal condensations in the head region. The simple squamous epithelium on the surface of leptomeninges developed during mesenchymal to epithelial transformation. Nestin appeared for the first time in week 7, EMA in week 8, while mesothelin appeared in week 22 of development. In the late fetal period and after birth, nestin expression decreased, whereas expression of EMA and mesothelin increased. EMA appeared in all surface epithelial cells and nodules, while mesothelin was found only in some of them. In adult meninges, all three proteins were predominantly localized in the surface epithelium and meningeal nodules. In meningothelial meningiomas (WHO grade I), EMA was detected in all tumor cells except in the endothelial cells, mesothelin characterized nests of tumor cells, while nestin was found predominantly in the walls of blood vessels. The distribution pattern of those proteins in normal meningeal and tumor cells indicates that nestin might characterize immature cells, while EMA and mesothelin appeared in maturing epithelial cells. Neoplastic transformation of these specific cell lineages contributes to the cell population in meningiomas. Copyright © 2010 Elsevier GmbH. All rights reserved.

Quantitative analysis of epithelial papillae in patients with oral lichen planus.

PubMed

López-Jornet, P; Camacho-Alonso, F; Molina-Miñano, F

2009-06-01

The oral mucosa is relatively vulnerable to pathological processes, and is often affected by autoimmune and malignant diseases. The oral epithelium is normally non-homogeneous, and joins to the connective tissue through interlocking of its downward projections in the form of papillae. This study aims to conduct a histomorphometric study of the epithelial papillae in patients with oral lichen planus (OLP). This study was based on 100 cheek mucosa biopsies from patients with OLP (66 white reticular and 34 atrophic-erosive) (13 males and 87 females, with a mean age of 54.95 +/- 13.64 years). A histological and morphometric evaluation was made, based on imaging analysis with MIP software 4.5 for studying the papillary structure in the patients with OLP. The mean epithelial thickness was 227.5 +/- 78.5 microm. The different papillary measures--BLS (distance from basal layer to epithelial surface), DPS (distance from dermal papilla top to epithelial surface), DPW (dermal papilla width), and DPD (interdermal papilla distance between two papillae)--yielded no statistically significant differences with respect to age, sex, smoking and clinical form. However, a significant correlation was observed in relation to papilla width and inflammatory infiltrate (P = 0.031). The application of this imaging system is useful for measuring variations in epithelial papillary architecture.

Epithelial self-healing is recapitulated by a 3D biomimetic E-cadherin junction.

PubMed

Cohen, Daniel J; Gloerich, Martijn; Nelson, W James

2016-12-20

Epithelial monolayers undergo self-healing when wounded. During healing, cells collectively migrate into the wound site, and the converging tissue fronts collide and form a stable interface. To heal, migrating tissues must form cell-cell adhesions and reorganize from the front-rear polarity characteristic of cell migration to the apical-basal polarity of an epithelium. However, identifying the "stop signal" that induces colliding tissues to cease migrating and heal remains an open question. Epithelial cells form integrin-based adhesions to the basal extracellular matrix (ECM) and E-cadherin-mediated cell-cell adhesions on the orthogonal, lateral surfaces between cells. Current biological tools have been unable to probe this multicellular 3D interface to determine the stop signal. We addressed this problem by developing a unique biointerface that mimicked the 3D organization of epithelial cell adhesions. This "minimal tissue mimic" (MTM) comprised a basal ECM substrate and a vertical surface coated with purified extracellular domain of E-cadherin, and was designed for collision with the healing edge of an epithelial monolayer. Three-dimensional imaging showed that adhesions formed between cells, and the E-cadherin-coated MTM resembled the morphology and dynamics of native epithelial cell-cell junctions and induced the same polarity transition that occurs during epithelial self-healing. These results indicate that E-cadherin presented in the proper 3D context constitutes a minimum essential stop signal to induce self-healing. That the Ecad:Fc MTM stably integrated into an epithelial tissue and reduced migration at the interface suggests that this biointerface is a complimentary approach to existing tissue-material interfaces.

Epithelial self-healing is recapitulated by a 3D biomimetic E-cadherin junction

PubMed Central

Cohen, Daniel J.; Gloerich, Martijn; Nelson, W. James

2016-01-01

Epithelial monolayers undergo self-healing when wounded. During healing, cells collectively migrate into the wound site, and the converging tissue fronts collide and form a stable interface. To heal, migrating tissues must form cell–cell adhesions and reorganize from the front-rear polarity characteristic of cell migration to the apical-basal polarity of an epithelium. However, identifying the "stop signal" that induces colliding tissues to cease migrating and heal remains an open question. Epithelial cells form integrin-based adhesions to the basal extracellular matrix (ECM) and E-cadherin–mediated cell–cell adhesions on the orthogonal, lateral surfaces between cells. Current biological tools have been unable to probe this multicellular 3D interface to determine the stop signal. We addressed this problem by developing a unique biointerface that mimicked the 3D organization of epithelial cell adhesions. This "minimal tissue mimic" (MTM) comprised a basal ECM substrate and a vertical surface coated with purified extracellular domain of E-cadherin, and was designed for collision with the healing edge of an epithelial monolayer. Three-dimensional imaging showed that adhesions formed between cells, and the E-cadherin-coated MTM resembled the morphology and dynamics of native epithelial cell–cell junctions and induced the same polarity transition that occurs during epithelial self-healing. These results indicate that E-cadherin presented in the proper 3D context constitutes a minimum essential stop signal to induce self-healing. That the Ecad:Fc MTM stably integrated into an epithelial tissue and reduced migration at the interface suggests that this biointerface is a complimentary approach to existing tissue–material interfaces. PMID:27930308

Inhibitors of acid secretion can benefit gastric wound repair independent of luminal pH effects on the site of damage

PubMed Central

Demitrack, Elise S; Aihara, Eitaro; Kenny, Susan; Varro, Andrea; Montrose, Marshall H

2012-01-01

Background and aims The authors’ goal was to measure pH at the gastric surface (pHo) to understand how acid secretion affects the repair of microscopic injury to the gastric epithelium. Methods Microscopic gastric damage was induced by laser light, during confocal/two-photon imaging of pH-sensitive dyes (Cl-NERF, BCECF) that were superfused over the mucosal surface of the exposed gastric corpus of anaesthetised mice. The progression of repair was measured in parallel with pHo. Experimental conditions included varying pH of luminal superfusates, and using omeprazole (60 mg/kg ip) or famotidine (30 mg/kg ip) to inhibit acid secretion. Results Similar rates of epithelial repair and resting pHo values (~pH 4) were reported in the presence of luminal pH 3 or pH 5. Epithelial repair was unreliable at luminal pH 2 and pHo was lower (2.5±0.2, P <0.05 vs pH 3). Epithelial repair was slower at luminal pH 7 and pHo was higher (6.4±0.1, P<0.001). In all conditions, pHo increased adjacent to damage. At luminal pH 3 or pH 7, omeprazole reduced maximal damage size and accelerated epithelial repair, although only at pH 3 did omeprazole further increase surface pH above the level caused by imposed damage. At luminal pH 7, famotidine also reduced maximal damage size and accelerated epithelial repair. Neither famotidine nor omeprazole raised plasma gastrin levels during the time course of the experiments. Conclusions Epithelial repair in vivo is affected by luminal pH variation, but the beneficial effects of acutely blocking acid secretion extend beyond simply raising luminal and/or surface pH. PMID:21997560

Epithelial adhesion molecules and the regulation of intestinal homeostasis during neutrophil transepithelial migration

PubMed Central

Sumagin, Ronen; Parkos, Charles A

2014-01-01

Epithelial adhesion molecules play essential roles in regulating cellular function and maintaining mucosal tissue homeostasis. Some form epithelial junctional complexes to provide structural support for epithelial monolayers and act as a selectively permeable barrier separating luminal contents from the surrounding tissue. Others serve as docking structures for invading viruses and bacteria, while also regulating the immune response. They can either obstruct or serve as footholds for the immune cells recruited to mucosal surfaces. Currently, it is well appreciated that adhesion molecules collectively serve as environmental cue sensors and trigger signaling events to regulate epithelial function through their association with the cell cytoskeleton and various intracellular adapter proteins. Immune cells, particularly neutrophils (PMN) during transepithelial migration (TEM), can modulate adhesion molecule expression, conformation, and distribution, significantly impacting epithelial function and tissue homeostasis. This review discusses the roles of key intestinal epithelial adhesion molecules in regulating PMN trafficking and outlines the potential consequences on epithelial function. PMID:25838976

Ex vivo gut culture for studying differentiation and migration of small intestinal epithelial cells

PubMed Central

Fu, Xing; Du, Min

2018-01-01

Epithelial cultures are commonly used for studying gut health. However, due to the absence of mesenchymal cells and gut structure, epithelial culture systems including recently developed three-dimensional organoid culture cannot accurately represent in vivo gut development, which requires intense cross-regulation of the epithelial layer with the underlying mesenchymal tissue. In addition, organoid culture is costly. To overcome this, a new culture system was developed using mouse embryonic small intestine. Cultured intestine showed spontaneous peristalsis, indicating the maintenance of the normal gut physiological structure. During 10 days of ex vivo culture, epithelial cells moved along the gut surface and differentiated into different epithelial cell types, including enterocytes, Paneth cells, goblet cells and enteroendocrine cells. We further used the established ex vivo system to examine the role of AMP-activated protein kinase (AMPK) on gut epithelial health. Tamoxifen-induced AMPKα1 knockout vastly impaired epithelial migration and differentiation of the developing ex vivo gut, showing the crucial regulatory function of AMPK α1 in intestinal health. PMID:29643147

The Impact of Test Dimensionality, Common-Item Set Format, and Scale Linking Methods on Mixed-Format Test Equating

ERIC Educational Resources Information Center

Öztürk-Gübes, Nese; Kelecioglu, Hülya

2016-01-01

The purpose of this study was to examine the impact of dimensionality, common-item set format, and different scale linking methods on preserving equity property with mixed-format test equating. Item response theory (IRT) true-score equating (TSE) and IRT observed-score equating (OSE) methods were used under common-item nonequivalent groups design.…

FOS: A Factored Operating Systems for High Assurance and Scalability on Multicores

DTIC Science & Technology

2012-08-01

computing. It builds on previous work in distributed and microkernel OSes by factoring services out of the kernel, and then further distributing each...2 3.0 Methods, Assumptions, and Procedures (System Design) .................................................. 4 3.1 Microkernel ...cooperating servers. We term such a service a fleet. Figure 2 shows the high-level architecture of fos. A small microkernel runs on every core

Effects of aging and exercise training on spinotrapezius muscle microvascular Po2 dynamics and vasomotor control

PubMed Central

McCullough, Danielle J.; Davis, Robert T.; Dominguez, James M.; Stabley, John N.; Bruells, Christian S.

2011-01-01

With advancing age, there is a reduction in exercise tolerance, resulting, in part, from a perturbed ability to match O2 delivery to uptake within skeletal muscle. In the spinotrapezius muscle (which is not recruited during incline treadmill running) of aged rats, we tested the hypotheses that exercise training will 1) improve the matching of O2 delivery to O2 uptake, evidenced through improved microvascular Po2 (PmO2), at rest and throughout the contractions transient; and 2) enhance endothelium-dependent vasodilation in first-order arterioles. Young (Y, ∼6 mo) and aged (O, >24 mo) Fischer 344 rats were assigned to control sedentary (YSED; n = 16, and OSED; n = 15) or exercise-trained (YET; n = 14, and OET; n = 13) groups. Spinotrapezius blood flow (via radiolabeled microspheres) was measured at rest and during exercise. Phosphorescence quenching was used to quantify PmO2 in vivo at rest and across the rest-to-twitch contraction (1 Hz, 5 min) transition in the spinotrapezius muscle. In a follow-up study, vasomotor responses to endothelium-dependent (acetylcholine) and -independent (sodium nitroprusside) stimuli were investigated in vitro. Blood flow to the spinotrapezius did not increase above resting values during exercise in either young or aged groups. Exercise training increased the precontraction baseline PmO2 (OET 37.5 ± 3.9 vs. OSED 24.7 ± 3.6 Torr, P < 0.05); the end-contracting PmO2 and the time-delay before PmO2 fell in the aged group but did not affect these values in the young. Exercise training improved maximal vasodilation in aged rats to acetylcholine (OET 62 ± 16 vs. OSED 27 ± 16%) and to sodium nitroprusside in both young and aged rats. Endurance training of aged rats enhances the PmO2 in a nonrecruited skeletal muscle and is associated with improved vascular smooth muscle function. These data support the notion that improvements in vascular function with exercise training are not isolated to the recruited muscle. PMID:21212242

Cell membrane-anchored MUC4 promotes tumorigenicity in epithelial carcinomas

PubMed Central

Xia, Pengpeng; Choi, Agnes Hakyung; Deng, Zengping; Yang, Yuqian; Zhao, Jing; Wang, Yiting; Hardwidge, Philip R.; Zhu, Guoqiang

2017-01-01

The cell surface membrane-bound mucin protein MUC4 promotes tumorigenicity, aggressive behavior, and poor outcomes in various types of epithelial carcinomas, including pancreatic, breast, colon, ovarian, and prostate cancer. This review summarizes the theories and findings regarding MUC4 function, and its role in epithelial carcinogenesis. Based on these insights, we developed an outline of the processes and mechanisms by which MUC4 critically supports the propagation and survival of cancer cells in various epithelial organs. MUC4 may therefore be a useful prognostic and diagnostic tool that improves our ability to eradicate various forms of cancer. PMID:27829225

Cell membrane-anchored MUC4 promotes tumorigenicity in epithelial carcinomas.

PubMed

Xia, Pengpeng; Choi, Agnes Hakyung; Deng, Zengping; Yang, Yuqian; Zhao, Jing; Wang, Yiting; Hardwidge, Philip R; Zhu, Guoqiang

2017-02-21

The cell surface membrane-bound mucin protein MUC4 promotes tumorigenicity, aggressive behavior, and poor outcomes in various types of epithelial carcinomas, including pancreatic, breast, colon, ovarian, and prostate cancer. This review summarizes the theories and findings regarding MUC4 function, and its role in epithelial carcinogenesis. Based on these insights, we developed an outline of the processes and mechanisms by which MUC4 critically supports the propagation and survival of cancer cells in various epithelial organs. MUC4 may therefore be a useful prognostic and diagnostic tool that improves our ability to eradicate various forms of cancer.

An essential amino acid induces epithelial β-defensin expression

PubMed Central

Fehlbaum, Pascale; Rao, Meena; Zasloff, Michael; Anderson, G. Mark

2000-01-01

Antimicrobial peptides constitute an important component of the mammalian innate immune response. Several types of antimicrobial peptides, including the β-defensins, are produced at epithelial surfaces in response to infectious threats. Here we show that a class of small molecules, including l-isoleucine and several of its analogs, can specifically induce epithelial β-defensin expression. This induction is transcriptional in nature and involves activation of the NF-κB/rel family of trans-activating factors. We hypothesize that these substances represent unique markers for the presence of pathogens and are recognized by innate immune pattern recognition receptors. Isoleucine or its analogs ultimately may have clinical utility as novel immunostimulants that could bolster the barrier defenses of mucosal surfaces. PMID:11058160

Inhibition of Protease-Epithelial Sodium Channel Signaling Improves Mucociliary Function in Cystic Fibrosis Airways.

PubMed

Reihill, James A; Walker, Brian; Hamilton, Robert A; Ferguson, Timothy E G; Elborn, J Stuart; Stutts, M Jackson; Harvey, Brian J; Saint-Criq, Vinciane; Hendrick, Siobhan M; Martin, S Lorraine

2016-09-15

In cystic fibrosis (CF) a reduction in airway surface liquid (ASL) height compromises mucociliary clearance, favoring mucus plugging and chronic bacterial infection. Inhibitors of the epithelial sodium channel (ENaC) have therapeutic potential in CF airways to reduce hyperstimulated sodium and fluid absorption to levels that can restore airway hydration. To determine whether a novel compound (QUB-TL1) designed to inhibit protease/ENaC signaling in CF airways restores ASL volume and mucociliary function. Protease activity was measured using fluorogenic activity assays. Differentiated primary airway epithelial cell cultures (F508del homozygotes) were used to determined ENaC activity (Ussing chamber recordings), ASL height (confocal microscopy), and mucociliary function (by tracking the surface flow of apically applied microbeads). Cell toxicity was measured using a lactate dehydrogenase assay. QUB-TL1 inhibits extracellularly located channel activating proteases (CAPs), including prostasin, matriptase, and furin, the activities of which are observed at excessive levels at the apical surface of CF airway epithelial cells. QUB-TL1-mediated CAP inhibition results in diminished ENaC-mediated Na(+) absorption in CF airway epithelial cells caused by internalization of a prominent pool of cleaved (active) ENaCγ from the cell surface. Importantly, diminished ENaC activity correlates with improved airway hydration status and mucociliary clearance. We further demonstrate QUB-TL1-mediated furin inhibition, which is in contrast to other serine protease inhibitors (camostat mesylate and aprotinin), affords protection against neutrophil elastase-mediated ENaC activation and Pseudomonas aeruginosa exotoxin A-induced cell death. QUB-TL1 corrects aberrant CAP activities, providing a mechanism to delay or prevent the development of CF lung disease in a manner independent of CF transmembrane conductance regulator mutation.

Impacts of distinct observations during the 2009 Prince William Sound field experiment: A data assimilation study

NASA Astrophysics Data System (ADS)

Li, Z.; Chao, Y.; Farrara, J.; McWilliams, J. C.

2012-12-01

A set of data assimilation experiments, known as Observing System Experiments (OSEs), are performed to assess the relative impacts of different types of observations acquired during the 2009 Prince William Sound Field Experiment. The observations assimilated consist primarily of three types: High Frequency (HF) radar surface velocities, vertical profiles of temperature/salinity (T/S) measured by ships, moorings, Autonomous Underwater Vehicles and gliders, and satellite sea surface temperatures (SSTs). The impact of all the observations, HF radar surface velocities, and T/S profiles is assessed. Without data assimilation, a frequently occurring cyclonic eddy in the central Sound is overly persistent and intense. The assimilation of the HF radar velocities effectively reduces these biases and improves the representation of the velocities as well as the T/S fields in the Sound. The assimilation of the T/S profiles improves the large scale representation of the temperature/salinity and also the velocity field in the central Sound. The combination of the HF radar surface velocities and sparse T/S profiles results in an observing system capable of representing the circulation in the Sound reliably and thus producing analyses and forecasts with useful skill. It is suggested that a potentially promising observing network could be based on satellite SSHs and SSTs along with sparse T/S profiles, and future satellite SSHs with wide swath coverage and higher resolution may offer excellent data that will be of great use for predicting the circulation in the Sound.

Detonation Nanodiamond Toxicity in Human Airway Epithelial Cells Is Modulated by Air Oxidation

EPA Science Inventory

Detonational nanodiamonds (DND), a nanomaterial with an increasing range of industrial and biomedical applications, have previously been shown to induce a pro-inflammatory response in cultured human airway epithelial cells (HAEC). We now show that surface modifications induced by...

Angiotensin-converting enzyme in epithelial and neuroepithelial cells.

PubMed

Defendini, R; Zimmerman, E A; Weare, J A; Alhenc-Gelas, F; Erdös, E G

1983-07-01

Angiotensin-converting enzyme (CE) occurs in three types of cell: endothelial, epithelial, and neuroepithelial. In all three, it appears to be bound to plasma membrane. With antisera to the human enzyme, CE is demonstrated in paraffin sections on the apical surface of epithelial cells in the proximal tubule of the kidney, the mucosa of the small intestine, the syncytial trophoblast of the placenta, and the choroid plexus. Epithelial CE is characteristically found on microvillous surfaces in contact with an effluent, well placed to act on substrate in flux. In the brain, CE occurs in nerve fibers and terminals, mainly mesiobasally and in basal ganglia. Mesiobasal CE coincides with other components of the renin-angiotensin system (RAS) in the choroid/ventricular fluid, the subfornical organ, and the magnocellular neurosecretory system of the hypothalamus. Extrapyramidal CE, however, may not be related to the RAS. In the substantia nigra and the globus pallidus, the enzyme has the same cellular distribution as two putative neuromodulators, substance P and enkephalin, the latter a known substrate of CE.

Interaction of Mycobacterium leprae with human airway epithelial cells: adherence, entry, survival, and identification of potential adhesins by surface proteome analysis.

PubMed

Silva, Carlos A M; Danelishvili, Lia; McNamara, Michael; Berredo-Pinho, Márcia; Bildfell, Robert; Biet, Franck; Rodrigues, Luciana S; Oliveira, Albanita V; Bermudez, Luiz E; Pessolani, Maria C V

2013-07-01

This study examined the in vitro interaction between Mycobacterium leprae, the causative agent of leprosy, and human alveolar and nasal epithelial cells, demonstrating that M. leprae can enter both cell types and that both are capable of sustaining bacterial survival. Moreover, delivery of M. leprae to the nasal septum of mice resulted in macrophage and epithelial cell infection in the lung tissue, sustaining the idea that the airways constitute an important M. leprae entry route into the human body. Since critical aspects in understanding the mechanisms of infection are the identification and characterization of the adhesins involved in pathogen-host cell interaction, the nude mouse-derived M. leprae cell surface-exposed proteome was studied to uncover potentially relevant adhesin candidates. A total of 279 cell surface-exposed proteins were identified based on selective biotinylation, streptavidin-affinity purification, and shotgun mass spectrometry; 11 of those proteins have been previously described as potential adhesins. In vitro assays with the recombinant forms of the histone-like protein (Hlp) and the heparin-binding hemagglutinin (HBHA), considered to be major mycobacterial adhesins, confirmed their capacity to promote bacterial attachment to epithelial cells. Taking our data together, they suggest that the airway epithelium may act as a reservoir and/or portal of entry for M. leprae in humans. Moreover, our report sheds light on the potentially critical adhesins involved in M. leprae-epithelial cell interaction that may be useful in designing more effective tools for leprosy control.

CD44 Staining of Cancer Stem-Like Cells Is Influenced by Down-Regulation of CD44 Variant Isoforms and Up-Regulation of the Standard CD44 Isoform in the Population of Cells That Have Undergone Epithelial-to-Mesenchymal Transition

PubMed Central

Biddle, Adrian; Gammon, Luke; Fazil, Bilal; Mackenzie, Ian C.

2013-01-01

CD44 is commonly used as a cell surface marker of cancer stem-like cells in epithelial tumours, and we have previously demonstrated the existence of two different CD44high cancer stem-like cell populations in squamous cell carcinoma, one having undergone epithelial-to-mesenchymal transition and the other maintaining an epithelial phenotype. Alternative splicing of CD44 variant exons generates a great many isoforms, and it is not known which isoforms are expressed on the surface of the two different cancer stem-like cell phenotypes. Here, we demonstrate that cancer stem-like cells with an epithelial phenotype predominantly express isoforms containing the variant exons, whereas the cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition down-regulate these variant isoforms and up-regulate expression of the standard CD44 isoform that contains no variant exons. In addition, we find that enzymatic treatments used to dissociate cells from tissue culture or fresh tumour specimens cause destruction of variant CD44 isoforms at the cell surface whereas expression of the standard CD44 isoform is preserved. This results in enrichment within the CD44high population of cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition and depletion from the CD44high population of cancer stem-like cells that maintain an epithelial phenotype, and therefore greatly effects the characteristics of any cancer stem-like cell population isolated based on expression of CD44. As well as effecting the CD44high population, enzymatic treatment also reduces the percentage of the total epithelial cancer cell population staining CD44-positive, with potential implications for studies that aim to use CD44-positive staining as a prognostic indicator. Analyses of the properties of cancer stem-like cells are largely dependent on the ability to accurately identify and assay these populations. It is therefore critical that consideration be given to use of multiple cancer stem-like cell markers and suitable procedures for cell isolation in order that the correct populations are assayed. PMID:23437366

Nanostructured Surfaces for Drug Delivery and Anti-Fibrosis

NASA Astrophysics Data System (ADS)

Kam, Kimberly Renee

Effective and cost-efficient healthcare is at the forefront of public discussion; on both personal and policy levels, technologies that improve therapeutic efficacy without the use of painful hypodermic needle injections or the use of harsh chemicals would prove beneficial to patients. Nanostructured surfaces as structure-mediated permeability enhancers introduce a potentially revolutionary approach to the field of drug delivery. Parental administration routes have been the mainstay technologies for delivering biologics because these therapeutics are too large to permeate epithelial barriers. However, there is a significant patient dislike for hypodermic needles resulting in reduced patient compliance and poor therapeutic results. We present an alternative strategy to harness the body's naturally occurring biological processes and transport mechanisms to enhance the drug transport of biologics across the epithelium. Our strategy offers a paradigm shift from traditional biochemical drug delivery vehicles by using nanotopography to loosen the epithelial barrier. Herein, we demonstrate that nanotopographical cues can be used to enable biologics > 66 kDa to be transported across epithelial monolayers by increasing paracellular transport. When placed in contact with epithelial cells, nanostructured films significantly increase the transport of albumin, IgG, and a model therapeutic, etanercept. Our work highlights the potential to use drug delivery systems which incorporate nanotopographical cues to increase the transport of biologics across epithelial tissue. Furthermore, we describe current advancements in nano- and microfabrication for applications in anti-fibrosis and wound healing. Influencing cellular responses to biomaterials is crucial in the field of tissue engineering and regenerative medicine. Since cells are surrounded by extracellular matrix features that are on the nanoscale, identifying nanostructures for imparting desirable cellular function could greatly impact the field. Due to the rise in micro and nanofabrication techniques borrowed from the advances in the microelectronics industry, previously unattainable nanostructured surfaces on a variety of biomaterials can be generated. We investigated how nanostructured surfaces with varying nanofeature aspect ratios can influence fibrosis. Thus, nanostructured surfaces show substantial progress for therapeutic applications in drug delivery and wound healing.

Computer simulations of the mechanical response of brushes on the surface of cancerous epithelial cells

NASA Astrophysics Data System (ADS)

Goicochea, A. Gama; Guardado, S. J. Alas

2015-08-01

We report a model for atomic force microscopy by means of computer simulations of molecular brushes on surfaces of biological interest such as normal and cancerous cervical epithelial cells. Our model predicts that the force needed to produce a given indentation on brushes that can move on the surface of the cell (called “liquid” brushes) is the same as that required for brushes whose ends are fixed on the cell’s surface (called “solid” brushes), as long as the tip of the microscope covers the entire area of the brush. Additionally, we find that cancerous cells are softer than normal ones, in agreement with various experiments. Moreover, soft brushes are found to display larger resistance to compression than stiff ones. This phenomenon is the consequence of the larger equilibrium length of the soft brushes and the cooperative association of solvent molecules trapped within the brushes, which leads to an increase in the osmotic pressure. Our results show that a careful characterization of the brushes on epithelial cells is indispensable when determining the mechanical response of cancerous cells.

Beneficial Autoimmunity at Body Surfaces – Immune Surveillance and Rapid Type 2 Immunity Regulate Tissue Homeostasis and Cancer

PubMed Central

Dalessandri, Tim; Strid, Jessica

2014-01-01

Epithelial cells (ECs) line body surface tissues and provide a physicochemical barrier to the external environment. Frequent microbial and non-microbial challenges such as those imposed by mechanical disruption, injury or exposure to noxious environmental substances including chemicals, carcinogens, ultraviolet-irradiation, or toxins cause activation of ECs with release of cytokines and chemokines as well as alterations in the expression of cell-surface ligands. Such display of epithelial stress is rapidly sensed by tissue-resident immunocytes, which can directly interact with self-moieties on ECs and initiate both local and systemic immune responses. ECs are thus key drivers of immune surveillance at body surface tissues. However, ECs have a propensity to drive type 2 immunity (rather than type 1) upon non-invasive challenge or stress – a type of immunity whose regulation and function still remain enigmatic. Here, we review the induction and possible role of type 2 immunity in epithelial tissues and propose that rapid immune surveillance and type 2 immunity are key regulators of tissue homeostasis and carcinogenesis. PMID:25101088

Royal Jelly Inhibits Pseudomonas aeruginosa Adherence and Reduces Excessive Inflammatory Responses in Human Epithelial Cells

PubMed Central

Susilowati, Heni; Amoh, Takashi; Hirao, Kouji; Hirota, Katsuhiko; Matsuo, Takashi; Miyake, Yoichiro

2017-01-01

Pseudomonas aeruginosa is a Gram-negative bacterium and causes respiratory infection especially in elderly patients. Royal jelly has been used worldwide as a traditional remedy and as a nutrient; however, the effect against P. aeruginosa is unclear. The aim of this study was to analyze antibacterial, antiadherent, and anti-inflammatory effects of royal jelly against P. aeruginosa. Wild-type strain PAO1 and clinical isolates of P. aeruginosa were used for antibacterial assay and antiadherent assay to abiotic surface and epithelial cells, which are pharynx (Detroit 562) and lung (NCI-H292) epithelial cells. In anti-inflammatory assay, epithelial cells were pretreated with royal jelly before bacterial exposure to investigate its inhibitory effect on interleukin (IL-8) and macrophage inflammatory protein-3α/CCL20 overproduction. Although royal jelly did not have antibacterial activity at concentration of 50% w/v, antiadherent activity was confirmed on the abiotic surface and epithelial cells under concentration of 25%. Pretreatment with royal jelly significantly inhibited overproduction of IL-8 and CCL20 from both cells. These results demonstrated that royal jelly inhibits P. aeruginosa adherence and protects epithelial cells from excessive inflammatory responses against P. aeruginosa infection. Our findings suggested that royal jelly may be a useful supplement as complementary and alternative medicine for preventing respiratory infection caused by P. aeruginosa. PMID:29075644

Royal Jelly Inhibits Pseudomonas aeruginosa Adherence and Reduces Excessive Inflammatory Responses in Human Epithelial Cells.

PubMed

Susilowati, Heni; Murakami, Keiji; Yumoto, Hiromichi; Amoh, Takashi; Hirao, Kouji; Hirota, Katsuhiko; Matsuo, Takashi; Miyake, Yoichiro

2017-01-01

Pseudomonas aeruginosa is a Gram-negative bacterium and causes respiratory infection especially in elderly patients. Royal jelly has been used worldwide as a traditional remedy and as a nutrient; however, the effect against P. aeruginosa is unclear. The aim of this study was to analyze antibacterial, antiadherent, and anti-inflammatory effects of royal jelly against P. aeruginosa . Wild-type strain PAO1 and clinical isolates of P. aeruginosa were used for antibacterial assay and antiadherent assay to abiotic surface and epithelial cells, which are pharynx (Detroit 562) and lung (NCI-H292) epithelial cells. In anti-inflammatory assay, epithelial cells were pretreated with royal jelly before bacterial exposure to investigate its inhibitory effect on interleukin (IL-8) and macrophage inflammatory protein-3 α /CCL20 overproduction. Although royal jelly did not have antibacterial activity at concentration of 50% w/v, antiadherent activity was confirmed on the abiotic surface and epithelial cells under concentration of 25%. Pretreatment with royal jelly significantly inhibited overproduction of IL-8 and CCL20 from both cells. These results demonstrated that royal jelly inhibits P. aeruginosa adherence and protects epithelial cells from excessive inflammatory responses against P. aeruginosa infection. Our findings suggested that royal jelly may be a useful supplement as complementary and alternative medicine for preventing respiratory infection caused by P. aeruginosa .

The Real-Time ObjectAgent Software Architecture for Distributed Satellite Systems

DTIC Science & Technology

2001-01-01

real - time operating system selection are also discussed. The fourth section describes a simple demonstration of real-time ObjectAgent. Finally, the...experience with C++. After selecting the programming language, it was necessary to select a target real - time operating system (RTOS) and embedded...ObjectAgent software to run on the OSE Real Time Operating System . In addition, she is responsible for the integration of ObjectAgent

Advanced Ultra-Violet (UV) Aircraft Fire Detection System. Volume 3. Ground Support Equipment (GSE) for System Check-Out

DTIC Science & Technology

1982-08-01

linsutaled * ifr rnif OC used nstead of ins resistors). 76 _ - Thil positions are as follows. 76 .APPENDIX A-2 3.2 PAper Loading TI’a6414ý-;jies lphnumeic ji...34i I I S.... . . I. ..... . .... •..................... ..- 4 . . o .. o . . .... . 149 :. ; , e~Vh -rom PPE ~t~ilk A-9 e" OSE S ~1: el/THIGH Is

MILSBILLS: Military Standard Billing System

DTIC Science & Technology

1985-01-01

disbursing offices and w’ose adjustments will be included in their Statement of Interfund 1,ansactions. c. Ensuring that there are adequate controls over...adjustments will be included in their Statement of Interfund Transactions. c. Ensuring that there are adequate controls over interfund related...by the DSAA. 3 iAutomatic adjustments may be withheld from specific customers if there is a pattern of abuse of this authority. When such a pattern

Detecting Target Data in Network Traffic

DTIC Science & Technology

2017-03-01

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Simultaneous assimilation of satellite NO2, O3, CO, and HNO3 data for the analysis of the tropospheric chemical composition

NASA Astrophysics Data System (ADS)

Miyazaki, K.; Eskes, H.; Sudo, K.

2012-04-01

Carbon monoxide (CO) and nitrogen oxides (NOx) play an important role in tropospheric chemistry through their influences on the ozone and hydroxyl radical (OH). The simultaneous optimization of various chemical components is expected to improve the emission inversion through the better description of the chemical feedbacks in the NOx- and CO-chemistry. This study aims to reproduce chemical composition distributions in the troposphere by combining information obtained from multiple satellite data sets. The emissions of CO and NOx, together with the 3D concentration fields of all forecasted chemical species in the global CTM CHASER have been simultaneously optimized using the ensemble Kalman filter (EnKF) data assimilation technique, and NO2, O3, CO, and HNO3 data obtained from OMI, TES, MOPITT, and MLS satellite measurements. The performance is evaluated against independent data from ozone sondes, aircraft measurements, GOME-2, and SCIAMACHY satellite data. Observing System Experiments (OSEs) have been carried out. These OSEs quantify the relative importance of each data set on constraining the emissions and concentrations. We confirmed that the simultaneous data assimilation improved the agreement with these independent data sets. The combined analysis of multiple data sets by means of advanced data assimilation system can provide a useful framework for the air quality research.

Observation impact studies with the Mercator Ocean analysis and forecasting systems

NASA Astrophysics Data System (ADS)

Remy, E. D.; Le Traon, P. Y.; Lellouche, J. M.; Drevillon, M.; Turpin, V.; Benkiran, M.

2016-02-01

Mercator Ocean produces and delivers in real-time ocean analysis and forecasts on a daily basis. The quality of the analysis highly relies on the availability and quality of the assimilated observations.Tools are developed to estimate the impact of the present network and to help designing the future evolutions of the observing systems in the context of near real time production of ocean analysis and forecasts. OSE and OSSE are the main approaches used in this context. They allow the assessment of the efficiency of a given data set to constrain the ocean model circulation through the data assimilation process. Illustrations will mainly focus on the present and future evolution of the Argo observation network and altimetry constellation, including the potential impact of future SWOT data. Our systems show clear sensitivities to observation array changes, mainly depending on the specified observation error and regional dynamic. Impact on non observed variables can be important and are important to evaluate. Dedicated diagnostics has to be define to measure the improvements bring by each data set. Alternative approaches to OSE and OSSE are also explored: approximate computation of DFS will be presented and discussed. Limitations of each approach will be discussed in the context of real time operation.

Linearly polarized GHz magnetization dynamics of spin helix modes in the ferrimagnetic insulator Cu2OSeO3.

PubMed

Stasinopoulos, I; Weichselbaumer, S; Bauer, A; Waizner, J; Berger, H; Garst, M; Pfleiderer, C; Grundler, D

2017-08-01

Linear dichroism - the polarization dependent absorption of electromagnetic waves- is routinely exploited in applications as diverse as structure determination of DNA or polarization filters in optical technologies. Here filamentary absorbers with a large length-to-width ratio are a prerequisite. For magnetization dynamics in the few GHz frequency regime strictly linear dichroism was not observed for more than eight decades. Here, we show that the bulk chiral magnet Cu 2 OSeO 3 exhibits linearly polarized magnetization dynamics at an unexpectedly small frequency of about 2 GHz at zero magnetic field. Unlike optical filters that are assembled from filamentary absorbers, the magnet is shown to provide linear polarization as a bulk material for an extremely wide range of length-to-width ratios. In addition, the polarization plane of a given mode can be switched by 90° via a small variation in width. Our findings shed a new light on magnetization dynamics in that ferrimagnetic ordering combined with antisymmetric exchange interaction offers strictly linear polarization and cross-polarized modes for a broad spectrum of sample shapes at zero field. The discovery allows for novel design rules and optimization of microwave-to-magnon transduction in emerging microwave technologies.

Groundwater Flow Model for Taos, New Mexico

NASA Astrophysics Data System (ADS)

Burck, P. W.; Barroll, P. W.; Core, A. B.; Rappuhn, D.

2003-12-01

The New Mexico Office of the State Engineer - Hydrology Bureau (OSE) has developed a regional groundwater flow model for Taos, New Mexico. The MODFLOW 2000 model will serve as a tool to evaluate alternatives in settlement negotiations in an on-going water rights adjudication. If current settlement negotiations fail, it is conceivable that the model might be used in support of litigation. OSE produced the model in cooperation with technical representatives of the various parties to the adjudication. Regional hydrogeologic data including well records, aquifer test results, stream flow measurements and seepage studies have been shared relatively freely among the parties. A recent deep drilling program conducted in conjunction with the negotiation effort has added substantially to the hydrogeologic data set. Among the hydrologic processes simulated by the model are mountain front recharge; areal recharge from precipitation; evapotranspiration; discharge from springs; river and stream flow; accretions to groundwater from irrigation return flow, seepage from acequias, canals, and ditches, and deep percolation; and pumping by municipal entities and mutual domestic water users associations. The resulting model files are available for all parties to review and evaluate. Comments are assessed and many have resulted in significant improvements to the model. At this stage, however, it is unclear whether adopting this cooperative approach will increase the likelihood of model acceptance by the parties.

The Contribution of the Airway Epithelial Cell to Host Defense.

PubMed

Stanke, Frauke

2015-01-01

In the context of cystic fibrosis, the epithelial cell has been characterized in terms of its ion transport capabilities. The ability of an epithelial cell to initiate CFTR-mediated chloride and bicarbonate transport has been recognized early as a means to regulate the thickness of the epithelial lining fluid and recently as a means to regulate the pH, thereby determining critically whether or not host defense proteins such as mucins are able to fold appropriately. This review describes how the epithelial cell senses the presence of pathogens and inflammatory conditions, which, in turn, facilitates the activation of CFTR and thus directly promotes pathogens clearance and innate immune defense on the surface of the epithelial cell. This paper summarizes functional data that describes the effect of cytokines, chemokines, infectious agents, and inflammatory conditions on the ion transport properties of the epithelial cell and relates these key properties to the molecular pathology of cystic fibrosis. Recent findings on the role of cystic fibrosis modifier genes that underscore the role of the epithelial ion transport in host defense and inflammation are discussed.

Use of micro-optical coherence tomography to analyze barrier integrity of intestinal epithelial cells (Conference Presentation)

NASA Astrophysics Data System (ADS)

Som, Avira; Leung, Hui Min; Chu, Kengyeh; Eaton, Alex D.; Hurley, Bryan P.; Tearney, Guillermo J.

2017-02-01

The intestinal epithelial barrier provides protection from external threats that enter the digestive system and persist beyond passage through the stomach. The effects of toxic agents on the intestinal epithelial cell monolayer have not been fully characterized at a cellular level as live imaging of this dynamic interplay at sufficient resolution to interpret cellular responses presents technological challenges. Using a high-resolution native contrast modality called Micro-Optical Coherence Tomography (μOCT), we generated real-time 3D images depicting the impact of the chemical agent EDTA on polarized intestinal epithelial monolayers. Within minutes following application of EDTA, we observed a change in the uniformity of epithelial surface thickness and loss of the edge brightness associated with the apical surface. These observations were measured by generating computer algorithms which quantify imaged-based events changing over time, thus providing parallel graphed data to pair with video. The imaging platform was designed to monitor epithelial monolayers prior to and following application of chemical agents in order to provide a comprehensive account of monolayer behavior at baseline conditions and immediately following exposure. Furthermore, the platform was designed to simultaneously measure continuous trans-epithelial electric resistance (TEER) in order to define the progressive loss of barrier integrity of the cell monolayer following exposure to toxic agents and correlate these findings to image-based metrics. This technological image-based experimental platform provides a novel means to characterize mechanisms that impact the intestinal barrier and, in future efforts, can be applied to study the impact of disease relevant agents such as enteric pathogens and enterotoxins.

Fusobacterium nucleatum binding to complement regulatory protein CD46 modulates the expression and secretion of cytokines and matrix metalloproteinases by oral epithelial cells.

PubMed

Mahtout, Hayette; Chandad, Fatiha; Rojo, Jose M; Grenier, Daniel

2011-02-01

Periodontitis is a chronic inflammatory disease that results in the destruction of the supporting tissues of the teeth. Gingival epithelial cells are an important mechanical barrier and participate in the host inflammatory response to periodontopathogens. The aim of the present study is to investigate the capacity of Fusobacterium nucleatum to bind to the complement regulatory protein CD46 expressed by oral epithelial cells and to determine the impact of the binding on the gene expression and protein secretion of interleukin (IL)-6, IL-8, and matrix metalloproteinase (MMP)-9 by oral epithelial cells. Binding of recombinant human CD46 to the surface of F. nucleatum was demonstrated by immunologic assays. After stimulation of oral epithelial cells with F. nucleatum, gene expression was determined by real-time polymerase chain reaction analysis while protein secretion was monitored by enzyme-linked immunosorbent assays. Heat and protease treatments of bacterial cells reduced CD46 binding. F. nucleatum-bound CD46 mediated the cleavage of C3b in the presence of factor I. Stimulating oral epithelial cells with F. nucleatum at a multiplicity of infection of 50 resulted in a significant upregulation of the gene expression and protein secretion of IL-6, IL-8, and MMP-9 by oral epithelial cells. However, pretreating the epithelial cells with an anti-CD46 polyclonal antibody attenuated the production of IL-6, IL-8, and MMP-9 in response to F. nucleatum. Such an inhibitory effect was not observed with non-specific antibodies. The present study demonstrates that F. nucleatum can bind the complement regulatory protein CD46. The interaction of F. nucleatum with epithelial cell surface CD46 may contribute to increasing the levels of proinflammatory mediators and MMPs in periodontal sites and consequently modulate tissue destruction.

Pathophysiology of Corneal Scarring in Persistent Epithelial Defects After PRK and Other Corneal Injuries.

PubMed

Wilson, Steven E; Medeiros, Carla S; Santhiago, Marcony R

2018-01-01

To analyze corneal persistent epithelial defects that occurred at 3 to 4 weeks after -4.50 diopter (D) photorefractive keratectomy (PRK) in rabbits and apply this pathophysiology to the treatment of persistent epithelial defects that occur after any corneal manipulations or diseases. Two of 168 corneas that had -4.50 D PRK to study epithelial basement membrane regeneration developed spontaneous persistent epithelial defects that did not heal at 3 weeks after PRK. These were studied with slit-lamp photographs, immunohistochemistry for the myofibroblast marker alpha-smooth muscle actin (α-SMA), and transmission electron microscopy. Myofibroblasts developed at the stromal surface within the persistent epithelial defect and for a short distance peripheral to the leading edge of the epithelium. No normal epithelial basement membrane was detectable within the persistent epithelial defect or for up to 0.3 mm behind the leading edge of the epithelium, although epithelial basement membrane had normally regenerated in other areas of the zone ablated by an excimer laser where the epithelium healed promptly. A persistent epithelial defect in the cornea results in the development of myofibroblasts and disordered extracellular matrix produced by these cells that together cause opacity within, and a short distance beyond, the persistent epithelial defect. Clinicians should treat persistent epithelial defects within 10 days of non-closure of the epithelium to facilitate epithelial healing to prevent long-term stromal scarring (fibrosis). [J Refract Surg. 2018;34(1):59-64.]. Copyright 2018, SLACK Incorporated.

Cells on Gels: Cell Behavior at the Air-Gel Interface

NASA Astrophysics Data System (ADS)

O'Bryan, Christopher; Hormel, Tristan; Bhattacharjee, Tapomoy; Sawyer, W.; Angelini, Thomas

Numerous different types of cells are often grown at air-liquid interfaces. For example, a common way to create cell spheroids is to disperse cells in a droplet of liquid media that hangs from the lid of a culture dish - the ``hanging drop'' method. Some types of epithelial cells form monolayers at the bottom of hanging drops, instead of spheroids. Corneal epithelial cells stratify and exhibit a tissue-like phenotype when attached to liquid permeable culture surfaces positioned at the air-liquid media interface (air-lifted culture). These widely used culture methods make experimentation challenging - imaging through hanging drops and air-lifted culture dishes is prohibitive. However, similar results may be achieved by culturing cells on hydrogel surfaces at the air-gel interface. In this talk we will describe a method for culturing cells at air-gel interfaces. We seed human corneal epithelial cells (hTCEpi) onto the surfaces of hydrogel networks and jammed microgels, exposed to air. Preliminary observations of cell behavior at the air-gel interface will be presented.

Increased Chain Length Promotes Pneumococcal Adherence and Colonization

PubMed Central

Rodriguez, Jesse L.; Dalia, Ankur B.

2012-01-01

Streptococcus pneumoniae is a mucosal pathogen that grows in chains of variable lengths. Short-chain forms are less likely to activate complement, and as a consequence they evade opsonophagocytic clearance more effectively during invasive disease. When grown in human nasal airway surface fluid, pneumococci exhibited both short- and long-chain forms. Here, we determined whether longer chains provide an advantage during colonization when the organism is attached to the epithelial surface. Chain-forming mutants and the parental strain grown under conditions to promote chain formation showed increased adherence to human epithelial cells (A549 cells) in vitro. Additionally, adherence to A549 cells selected for longer chains within the wild-type strain. In vivo in a murine model of colonization, chain-forming mutants outcompeted the parental strain. Together, our results demonstrate that morphological heterogeneity in the pneumococcus may promote colonization of the upper respiratory tract by enhancing the ability of the organism to bind to the epithelial surface. PMID:22825449

Galectin-8 regulates targeting of Gp135/podocalyxin and lumen formation at the apical surface of renal epithelial cells.

PubMed

Lim, HooiCheng; Yu, Chun-Ying; Jou, Tzuu-Shuh

2017-11-01

Establishment of apical-basal polarity, through correct targeting of polarity determinants to distinct domains of the plasma membrane, is a fundamental process for the development of functioning epithelial tubules. Here we report that galectin (Gal)-8 regulates apical-basal polarity of Madin-Darby canine kidney (MDCK) cells via apical targeting of 135-kDa glycoprotein (Gp135). Gal-8 interacts with newly synthesized Gp135 in a glycan-dependent manner. Gal-8 knockdown induces aberrant lumens at the lateral domain and mistargeting of Gp135 to this structure, thus disrupting the kidney epithelial polarity of MDCK cells, which organize lumens at the apical surface. The O -glycosylation deletion mutant of Gp135 phenocopies the effect of Gal-8 knockdown, which suggests that Gal-8 is the decoding machinery for the apical sorting signals of Gp135 residing at its O -glycosylation-rich region. Collectively, our results reveal a new role of Gal-8 in the development of luminal organs by regulating targeting of apical polarity protein Gp135.-Lim, H., Yu, C.-Y., Jou, T.-S. Galectin-8 regulates targeting of Gp135/podocalyxin and lumen formation at the apical surface of renal epithelial cells. © FASEB.

Biological effects of desert dust in respiratory epithelial cells and a murine model.

EPA Science Inventory

Abstract As a result of the challenge of recent dust storms to public health, we tested the postulate that desert dust collected in the southwestern United States could impact a biological effect in respiratory epithelial cells and an animal model. Two samples of surface sedime...

Cell reintegration: Stray epithelial cells make their way home.

PubMed

Wilson, Tyler J; Bergstralh, Dan T

2017-06-01

Ongoing work shows that misplaced epithelial cells have the capacity to reintegrate back into tissue layers. This movement appears to underlie tissue stability and may also control aspects of tissue structure. A recent study reveals that cell reintegration in at least one tissue, the Drosophila follicular epithelium, is based on adhesion molecules that line lateral cell surfaces. In this article we will review these observations, discuss their implications for epithelial tissue development and maintenance, and identify future directions for study. © 2017 WILEY Periodicals, Inc.

Analysis of Free Amino Acids in Different Extracts of Orthosiphon stamineus Leaves by High-Performance Liquid Chromatography Combined with Solid-Phase Extraction.

PubMed

Shafaei, Armaghan; Halim, Nor Hidayah Ab; Zakaria, Norhidayah; Ismail, Zhari

2017-10-01

Orthosiphon stamineus (OS) Benth is a medicinal plant and native in Southeast Asia. Previous studies have shown that OS leaves possess antioxidant, cytotoxic, diuretic, antihypertensive, and uricosuric effects. These beneficial effects have been attributed to the presence of primary and secondary metabolites such as polyphenols, amino acids, and flavonoids. To develop and validate an high-performance liquid chromatography (HPLC)-diode array detector (DAD) method combined with solid-phase extraction that involves precolumn derivatization with O -phthaladehyde for simultaneous analysis of free amino acids in OS leaves extracts. OS leaves were extracted with water (OS-W), ethanol (OS-E), methanol (OS-M), 50% ethanol (OS-EW), and 50% methanol (OS-MW). The extracts were treated by C18 cartridge before derivatization, resulting in great improvement of separation by Zorbox Eclipse XDB-C 18 column. The HPLC-DAD method was successfully developed and validated for analyzing the contents of free amino acids in OS extracts. The results showed that l-aspartic acid with 0.93 ± 0.01 nmol/mg was the major free amino acid in OS-W extract. However, in OS-E, OS-M, OS-EW, and OS-MW, l-glutamic acid with 3.53 ± 0.16, 2.17 ± 0.10, 4.01 ± 0.12, and 2.49 ± 0.12 nmol/mg, respectively, was the major free amino acid. Subsequently, l-serine, which was detected in OS-W, OS-E, and OS-M, was the minor free amino acid with 0.33 ± 0.02, 0.12 ± 0.01, and 0.06 ± 0.01 nmol/mg, respectively. However, l-threonine with 0.26 ± 0.02 and 0.19 ± 0.08 nmol/mL in OS-EW and OS-MW, respectively, had the lowest concentration compared with other amino acid components. All validation parameters of the developed method indicate that the method is reliable and efficient to simultaneously determine the free amino acids content for routine analysis of OS extracts. The HPLC-DAD method combined with solid phase extraction was successfully developed and validated for simultaneous determination and quantification of 17 free amino acids in Orthosiphon stamineus (OS) Benth extractsOS extracts were found to be rich in free amino acid contentL-aspartic acid was the major free amino acid in OS water extract while, in OS ethanol, methanol, 50% ethanol and 50% methanol extracts, L-glutamic acid was the major free amino acidL-serine was the minor free amino acid in OS water, ethanol and methanol extracts while, in OS 50% ethanol and 50% methanol extracts, L-threonine had the lowest concentration compared to other amino acid components. Abbreviations used: HPLC-DAD: High-Performance Liquid Chromatography with Diode-Array Detection, OS: Orthosiphon stamineus , OS-W: Orthosiphon stamineus water extract, OS-E: Orthosiphon stamineus ethanol extract, OS-M: Orthosiphon stamineus methanol extract, OS-EW: Orthosiphon stamineus 50% ethanol extract, OS-MW: Orthosiphon stamineus 50% methanol extract, OPA: O-phthaladehyde , SPE: Solid Phase Extraction, UV: Ultraviolet, LOD: Limit of Detection, LOQ: Limit of Quantification, RSD: Relative Standard Deviation.

Epithelial Microvilli Establish an Electrostatic Barrier to Microbial Adhesion

PubMed Central

Bennett, Kaila M.; Walker, Sharon L.

2014-01-01

Microvilli are membrane extensions on the apical surface of polarized epithelia, such as intestinal enterocytes and tubule and duct epithelia. One notable exception in mucosal epithelia is M cells, which are specialized for capturing luminal microbial particles; M cells display a unique apical membrane lacking microvilli. Based on studies of M cell uptake under different ionic conditions, we hypothesized that microvilli may augment the mucosal barrier by providing an increased surface charge density from the increased membrane surface and associated glycoproteins. Thus, electrostatic charges may repel microbes from epithelial cells bearing microvilli, while M cells are more susceptible to microbial adhesion. To test the role of microvilli in bacterial adhesion and uptake, we developed polarized intestinal epithelial cells with reduced microvilli (“microvillus-minus,” or MVM) but retaining normal tight junctions. When tested for interactions with microbial particles in suspension, MVM cells showed greatly enhanced adhesion and uptake of particles compared to microvillus-positive cells. This preference showed a linear relationship to bacterial surface charge, suggesting that microvilli resist binding of microbes by using electrostatic repulsion. Moreover, this predicts that pathogen modification of electrostatic forces may contribute directly to virulence. Accordingly, the effacement effector protein Tir from enterohemorrhagic Escherichia coli O157:H7 expressed in epithelial cells induced a loss of microvilli with consequent enhanced microbial binding. These results provide a new context for microvillus function in the host-pathogen relationship, based on electrostatic interactions. PMID:24778113

Interaction of Mycobacterium leprae with Human Airway Epithelial Cells: Adherence, Entry, Survival, and Identification of Potential Adhesins by Surface Proteome Analysis

PubMed Central

Silva, Carlos A. M.; Danelishvili, Lia; McNamara, Michael; Berredo-Pinho, Márcia; Bildfell, Robert; Biet, Franck; Rodrigues, Luciana S.; Oliveira, Albanita V.

2013-01-01

This study examined the in vitro interaction between Mycobacterium leprae, the causative agent of leprosy, and human alveolar and nasal epithelial cells, demonstrating that M. leprae can enter both cell types and that both are capable of sustaining bacterial survival. Moreover, delivery of M. leprae to the nasal septum of mice resulted in macrophage and epithelial cell infection in the lung tissue, sustaining the idea that the airways constitute an important M. leprae entry route into the human body. Since critical aspects in understanding the mechanisms of infection are the identification and characterization of the adhesins involved in pathogen-host cell interaction, the nude mouse-derived M. leprae cell surface-exposed proteome was studied to uncover potentially relevant adhesin candidates. A total of 279 cell surface-exposed proteins were identified based on selective biotinylation, streptavidin-affinity purification, and shotgun mass spectrometry; 11 of those proteins have been previously described as potential adhesins. In vitro assays with the recombinant forms of the histone-like protein (Hlp) and the heparin-binding hemagglutinin (HBHA), considered to be major mycobacterial adhesins, confirmed their capacity to promote bacterial attachment to epithelial cells. Taking our data together, they suggest that the airway epithelium may act as a reservoir and/or portal of entry for M. leprae in humans. Moreover, our report sheds light on the potentially critical adhesins involved in M. leprae-epithelial cell interaction that may be useful in designing more effective tools for leprosy control. PMID:23670556

Mycoplasma pulmonis Inhibits Electrogenic Ion Transport across Murine Tracheal Epithelial Cell Monolayers

PubMed Central

Lambert, Linda C.; Trummell, Hoa Q.; Singh, Ashvani; Cassell, Gail H.; Bridges, Robert J.

1998-01-01

Murine chronic respiratory disease is characterized by persistent colonization of tracheal and bronchial epithelial cell surfaces by Mycoplasma pulmonis, submucosal and intraluminal immune and inflammatory cells, and altered airway activity. To determine the direct effect of M. pulmonis upon transepithelial ion transport in the absence of immune and inflammatory cell responses, primary mouse tracheal epithelial cell monolayers (MTEs) were apically infected and assayed in Ussing chambers. M. pulmonis-infected MTEs, but not those infected with a nonmurine mycoplasma, demonstrated reductions in amiloride-sensitive Na+ absorption, cyclic AMP, and cholinergic-stimulated Cl− secretion and transepithelial resistance. These effects were shown to require interaction of viable organisms with the apical surface of the monolayer and to be dependent upon organism number and duration of infection. Altered transport due to M. pulmonis was not merely a result of epithelial cell death as evidenced by the following: (i) active transport of Na+ and Cl−, albeit at reduced rates; (ii) normal cell morphology, including intact tight junctions, as demonstrated by electron microscopy; (iii) maintenance of a mean transepithelial resistance of 440 Ω/cm2; and (iv) lack of leakage of fluid from the basolateral to the apical surface of the monolayer. Alteration in epithelial ion transport in vitro is consistent with impaired pulmonary clearance and altered airway function in M. pulmonis-infected animals. Furthermore, the ability of M. pulmonis to alter transport without killing the host cell may explain its successful parasitism and long-term persistence in the host. Further study of the MTE-M. pulmonis model should elucidate the molecular mechanisms which mediate this reduction in transepithelial ion transport. PMID:9423868

Mammary collective cell migration involves transient loss of epithelial features and individual cell migration within the epithelium

PubMed Central

Ewald, Andrew J.; Huebner, Robert J.; Palsdottir, Hildur; Lee, Jessie K.; Perez, Melissa J.; Jorgens, Danielle M.; Tauscher, Andrew N.; Cheung, Kevin J.; Werb, Zena; Auer, Manfred

2012-01-01

Normal mammary morphogenesis involves transitions between simple and multilayered epithelial organizations. We used electron microscopy and molecular markers to determine whether intercellular junctions and apico-basal polarity were maintained in the multilayered epithelium. We found that multilayered elongating ducts had polarized apical and basal tissue surfaces both in three-dimensional culture and in vivo. However, individual cells were only polarized on surfaces in contact with the lumen or extracellular matrix. The basolateral marker scribble and the apical marker atypical protein kinase C zeta localized to all interior cell membranes, whereas PAR3 displayed a cytoplasmic localization, suggesting that the apico-basal polarity was incomplete. Despite membrane localization of E-cadherin and β-catenin, we did not observe a defined zonula adherens connecting interior cells. Instead, interior cells were connected through desmosomes and exhibited complex interdigitating membrane protrusions. Single-cell labeling revealed that individual cells were both protrusive and migratory within the epithelial multilayer. Inhibition of Rho kinase (ROCK) further reduced intercellular adhesion on apical and lateral surfaces but did not disrupt basal tissue organization. Following morphogenesis, segregated membrane domains were re-established and junctional complexes re-formed. We observed similar epithelial organization during mammary morphogenesis in organotypic culture and in vivo. We conclude that mammary epithelial morphogenesis involves a reversible, spatially limited, reduction in polarity and intercellular junctions and active individualistic cell migration. Our data suggest that reductions in polarity and adhesion during breast cancer progression might reflect partial recapitulation of a normal developmental program. PMID:22344263

Critical Determinants of Uptake and Translocation of Nanoparticles by the Human Pulmonary Alveolar Epithelium

PubMed Central

2015-01-01

The ability to manipulate the size and surface properties of nanomaterials makes them a promising vector for improving drug delivery and efficacy. Inhalation is a desirable route of administration as nanomaterials preferentially deposit in the alveolar region, a large surface area for drug absorption. However, as yet, the mechanisms by which particles translocate across the alveolar epithelial layer are poorly understood. Here we show that human alveolar type I epithelial cells internalize nanoparticles, whereas alveolar type II epithelial cells do not, and that nanoparticles translocate across the epithelial monolayer but are unable to penetrate the tight junctions between cells, ruling out paracellular translocation. Furthermore, using siRNA, we demonstrate that 50 nm nanoparticles enter largely by passive diffusion and are found in the cytoplasm, whereas 100 nm nanoparticles enter primarily via clathrin- and also caveolin-mediated endocytosis and are found in endosomes. Functionalization of nanoparticles increases their uptake and enhances binding of surfactant which further promotes uptake. Thus, we demonstrate that uptake and translocation across the pulmonary epithelium is controlled by alveolar type I epithelial cells, and furthermore, we highlight a number of factors that should be considered when designing new nanomedicines in order to improve drug delivery to the lung. PMID:25360809

Extended Deterrence and Arms Control: A Collection of Conference Papers

DTIC Science & Technology

1988-05-01

possessing a nuclear 1OSee also Robbin F. Laird, France, the Soviet Union, and the Nuclear Issue, Boulder, Colorado , and London, 1984. "Uwe Nerlich, "Die...War and the Army, Voyenizdat, Moscow, 1955, p. 168, as cited in Thomas W. Wolfe , Soviet Strategy at the Crossroads, Harvard University Press...a whole is concerned, the reintroduction of strategic defenses in the nuclear equation between the superpowers is clearly not a positive prospect. It

Establishing Competitive Production Sources. A Handbook for Program Managers

DTIC Science & Technology

1984-08-01

purp’ ose of t6-is handbocok is to ’orovide :he ’ projram ma~iager and otner aca ’u1sitiofl cff’caS with a systenatic guide to the assessment ...manager must assess the feasibility and effectiveness of production competition in - a highly detailed, rigorous, and quantitative way. These...the program manager and other acquisition officials with a systematic guide to the assessment , implementation, and execution of production competition

Learning and Memory Enhancement by Neuropeptides

DTIC Science & Technology

1986-12-31

organometal neurotoxin , ,• trimethyl n (TMT) oon I autoshaping model, it which rats learn to touch a lever to obtain f . Trialkyltins are used as stabilizers... Autoshaped Behavior Caused by Low E oses of Trimethyltin: No Evidence of Storage or Retrieval Deficits"). This study separates ’non-specific" behavioral...TMT does not i mpair performance of easy versions of the autoshaping task with identical sensorimotor ," - and moti ational requirements, but when a

The Pseudomonas aeruginosa exopolysaccharide Psl facilitates surface adherence and NF-kappaB activation in A549 cells.

PubMed

Byrd, Matthew S; Pang, Bing; Mishra, Meenu; Swords, W Edward; Wozniak, Daniel J

2010-06-29

In order for the opportunistic Gram-negative pathogen Pseudomonas aeruginosa to cause an airway infection, the pathogen interacts with epithelial cells and the overlying mucous layer. We examined the contribution of the biofilm polysaccharide Psl to epithelial cell adherence and the impact of Psl on proinflammatory signaling by flagellin. Psl has been implicated in the initial attachment of P. aeruginosa to biotic and abiotic surfaces, but its direct role in pathogenesis has not been evaluated (L. Ma, K. D. Jackson, R. M. Landry, M. R. Parsek, and D. J. Wozniak, J. Bacteriol. 188:8213-8221, 2006). Using an NF-kappaB luciferase reporter system in the human epithelial cell line A549, we show that both Psl and flagellin are necessary for full activation of NF-kappaB and production of the interleukin 8 (IL-8) chemokine. We demonstrate that Psl does not directly stimulate NF-kappaB activity, but indirectly as a result of increasing contact between bacterial cells and epithelial cells, it facilitates flagellin-mediated proinflammatory signaling. We confirm differential adherence of Psl and/or flagellin mutants by scanning electron microscopy and identify Psl-dependent membrane structures that may participate in adherence. Although we hypothesized that Psl would protect P. aeruginosa from recognition by the epithelial cell line A549, we instead observed a positive role for Psl in flagellin-mediated NF-kappaB activation, likely as a result of increasing contact between bacterial cells and epithelial cells.

The Pseudomonas aeruginosa Exopolysaccharide Psl Facilitates Surface Adherence and NF-κB Activation in A549 Cells

PubMed Central

Byrd, Matthew S.; Pang, Bing; Mishra, Meenu; Swords, W. Edward; Wozniak, Daniel J.

2010-01-01

In order for the opportunistic Gram-negative pathogen Pseudomonas aeruginosa to cause an airway infection, the pathogen interacts with epithelial cells and the overlying mucous layer. We examined the contribution of the biofilm polysaccharide Psl to epithelial cell adherence and the impact of Psl on proinflammatory signaling by flagellin. Psl has been implicated in the initial attachment of P. aeruginosa to biotic and abiotic surfaces, but its direct role in pathogenesis has not been evaluated (L. Ma, K. D. Jackson, R. M. Landry, M. R. Parsek, and D. J. Wozniak, J. Bacteriol. 188:8213–8221, 2006). Using an NF-κB luciferase reporter system in the human epithelial cell line A549, we show that both Psl and flagellin are necessary for full activation of NF-κB and production of the interleukin 8 (IL-8) chemokine. We demonstrate that Psl does not directly stimulate NF-κB activity, but indirectly as a result of increasing contact between bacterial cells and epithelial cells, it facilitates flagellin-mediated proinflammatory signaling. We confirm differential adherence of Psl and/or flagellin mutants by scanning electron microscopy and identify Psl-dependent membrane structures that may participate in adherence. Although we hypothesized that Psl would protect P. aeruginosa from recognition by the epithelial cell line A549, we instead observed a positive role for Psl in flagellin-mediated NF-κB activation, likely as a result of increasing contact between bacterial cells and epithelial cells. PMID:20802825

EMMPRIN Modulates Epithelial Barrier Function through a MMP–Mediated Occludin Cleavage

PubMed Central

Huet, Eric; Vallée, Benoit; Delbé, Jean; Mourah, Samia; Prulière-Escabasse, Virginie; Tremouilleres, Magali; Kadomatsu, Kenji; Doan, Serge; Baudouin, Christophe; Menashi, Suzanne; Gabison, Eric E.

2011-01-01

Dry eye is a common disease that develops as a result of alteration of tear fluid, leading to osmotic stress and a perturbed epithelial barrier. Matrix metalloproteinase-9 (MMP-9) may be important in dry eye disease, as its genetic knockout conferred resistance to the epithelial disruption. We show that extracellular matrix metalloproteinase inducer (EMMPRIN; also termed CD147), an inducer of MMP expression, participates in the pathogenesis of dry eye through MMP-mediated cleavage of occludin, an important component of tight junctions. EMMPRIN expression was increased on the ocular surface of dry eye patients and correlated with those of MMP-9. High osmolarity in cell culture, mimicking dry eye conditions, increased both EMMPRIN and MMP-9 and resulted in the disruption of epithelial junctions through the cleavage of occludin. Exogenously added recombinant EMMPRIN had similar effects that were abrogated in the presence of the MMP inhibitor marimastat. Membrane occludin immunostaining was markedly increased in the apical corneal epithelium of both EMMPRIN and MMP-9 knock-out mice. Furthermore, an inverse correlation between EMMPRIN and occludin membrane staining was consistently observed both in vitro and in vivo as a function of corneal epithelial cells differentiation. These data suggest a possible role of EMMPRIN in regulating the amount of occludin at the cell surface in homeostasis beyond pathological situations such as dry eye disease, and EMMPRIN may be essential for the formation and maintenance of organized epithelial structure. PMID:21777561

Cockroach protease allergen induces allergic airway inflammation via epithelial cell activation

PubMed Central

Kale, Sagar L.; Agrawal, Komal; Gaur, Shailendra Nath; Arora, Naveen

2017-01-01

Protease allergens are known to enhance allergic inflammation but their exact role in initiation of allergic reactions at mucosal surfaces still remains elusive. This study was aimed at deciphering the role of serine protease activity of Per a 10, a major cockroach allergen in initiation of allergic inflammation at mucosal surfaces. We demonstrate that Per a 10 increases epithelial permeability by disruption of tight junction proteins, ZO-1 and occludin, and enhances the migration of Monocyte derived dendritic cell precursors towards epithelial layer as exhibited by trans-well studies. Per a 10 exposure also leads to secretion of IL-33, TSLP and intracellular Ca2+ dependent increase in ATP levels. Further, in vivo experiments revealed that Per a 10 administration in mice elevated allergic inflammatory parameters along with high levels of IL-33, TSLP, IL-1α and uric acid in the mice lungs. We next demonstrated that Per a 10 cleaves CD23 (low affinity IgE receptor) from the surface of PBMCs and purified B cells and CD25 (IL-2 receptor) from the surface of PBMCs and purified T cells in an activity dependent manner, which might favour Th2 responses. In conclusion, protease activity of Per a 10 plays a significant role in initiation of allergic airway inflammation at the mucosal surfaces. PMID:28198394

PERP, a host tetraspanning membrane protein, is required for S almonella‐induced inflammation

PubMed Central

Hallstrom, Kelly N.; Srikanth, C. V.; Agbor, Terence A.; Dumont, Christopher M.; Peters, Kristen N.; Paraoan, Luminita; Casanova, James E.; Boll, Erik J.

2015-01-01

Summary S almonella enterica  Typhimurium induces intestinal inflammation through the activity of type III secreted effector (T3SE) proteins. Our prior results indicate that the secretion of the T3SE SipA and the ability of SipA to induce epithelial cell responses that lead to induction of polymorphonuclear transepithelial migration are not coupled to its direct delivery into epithelial cells from S almonella. We therefore tested the hypothesis that SipA interacts with a membrane protein located at the apical surface of intestinal epithelial cells. Employing a split ubiquitin yeast‐two‐hybrid screen, we identified the tetraspanning membrane protein, p53 effector related to PMP‐22 (PERP), as a SipA binding partner. SipA and PERP appear to have intersecting activities as we found PERP to be involved in proinflammatory pathways shown to be regulated by SipA. In sum, our studies reveal a critical role for PERP in the pathogenesis of S. Typhimurium, and for the first time demonstrate that SipA, a T3SE protein, can engage a host protein at the epithelial surface. PMID:25486861

Characterization of Epithelial Progenitors in Normal Human Palatine Tonsils and Their HPV16 E6/E7-Induced Perturbation

PubMed Central

Kang, Sung Yoon Catherine; Kannan, Nagarajan; Zhang, Lewei; Martinez, Victor; Rosin, Miriam P.; Eaves, Connie J.

2015-01-01

Summary Human palatine tonsils are oropharyngeal lymphoid tissues containing multiple invaginations (crypts) in which the continuity of the outer surface epithelium is disrupted and the isolated epithelial cells intermingle with other cell types. We now show that primitive epithelial cells detectable in vitro in 2D colony assays and in a 3D culture system are CD44+NGFR+ and present in both surface and crypt regions. Transcriptome analysis indicated a high similarity between CD44+NGFR+ cells in both regions, although those isolated from the crypt contained a higher proportion of the most primitive (holo)clonogenic cells. Lentiviral transduction of CD44+NGFR+ cells from both regions with human papillomavirus 16-encoded E6/E7 prolonged their growth in 2D cultures and caused aberrant differentiation in 3D cultures. Our findings therefore reveal a shared, site-independent, hierarchical organization, differentiation potential, and transcriptional profile of normal human tonsillar epithelial progenitor cells. They also introduce a new model for investigating the mechanisms of their transformation. PMID:26527383

Structural and ultrastructural features of the agouti tongue (Dasyprocta aguti Linnaeus, 1766)

PubMed Central

Ciena, Adriano Polican; Bolina, Cristina de Sousa; de Almeida, Sonia Regina Yokomizo; Rici, Rose Eli Grassi; de Oliveira, Moacir Franco; da da Silva, Marcelo Cavenaghi Pereira; Miglino, Maria Angélica; Watanabe, Ii-sei

2013-01-01

The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three-dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V-shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell-surface microridges were observed. These structural features, including the three-dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae. PMID:23701183

Fibrin glue inhibits migration of ocular surface epithelial cells

PubMed Central

Yeung, A M; Faraj, L A; McIntosh, O D; Dhillon, V K; Dua, H S

2016-01-01

Purpose Fibrin glue has been used successfully in numerous ophthalmic surgical procedures. Recently, fibrin glue has been used in limbal stem cell transplantation to reduce both operative time and to negate the need for sutures. The aim of this study was to determine the effects of fibrin glue on epithelial cell migration in vitro. Methods Corneoscleral rims were split to retain the epithelial layer, Bowman's layer, and anterior stroma. Rims were cut into eight equal-sized pieces and were placed directly on culture plates or affixed with fibrin glue. Rims were maintained in culture for 25 days and epithelial cell growth was monitored. Cells were photographed to measure area or growth and immunofluorescence staining of explants for fibrin was performed. Results Explants that were glued demonstrated significantly delayed epithelial cell growth and migration as compared with explants without glue. By day 16, all fibrin glue had dissolved and coincided with onset of cell growth from glued explants. Cell growth commenced between days 3 and 4 for control explants without glue and around days 14–16 for explants with fibrin glue. Conclusions Fibrin glue delays epithelial cell migration by acting as a physical barrier and can potentially interfere with explant-derived limbal epithelial cell migration on to the corneal surface. We propose that glue should be used to attach the conjunctival frill of the limbal explant but care should be taken to ensure that the glue does not wrap around the explant if used to secure the explant as well. Strategic use of glue, to attach the recessed conjunctiva, can be advantageous in delaying conjunctival cell migration and reducing the need for sequential sector conjunctival epitheliectomy. PMID:27367746

The world of epithelial sheets.

PubMed

Honda, Hisao

2017-06-01

An epithelium is a layer of closely connected cells covering the body or lining a body cavity. In this review, several fundamental questions are addressed regarding the epithelium. (i) While an epithelium functions as barrier against the external environment, how is barrier function maintained during its construction? (ii) What determines the apical and basal sides of epithelial layer? (iii) Is there any relationship between the apical side of the epithelium and the apical membrane of an epithelial cell? (iv) Why are hepatocytes (liver cells) called epithelial, even though they differ completely from column-like shape of typical epithelial cells? Keeping these questions in mind, multiple shapes of epithelia were considered, extracting a few of their elemental processes, and constructing a virtual world of epithelia by combining them. Epithelial cells were also classified into several types based on the number of apical domains of each cell. In addition, an intracellular organelle was introduced within epithelial cells, the vacuolar apical compartment (VAC), which is produced within epithelial cells surrounded by external cell matrix (ECM). The VAC interacts with areas of cell-cell contact of the cell surface membrane and is converted to apical membrane. The properties of VACs enable us to answer the initial questions posed above. Finally, the genetic and molecular mechanisms of epithelial morphogenesis are discussed. © 2017 Japanese Society of Developmental Biologists.

Role of calcium signaling in epithelial bicarbonate secretion.

PubMed

Jung, Jinsei; Lee, Min Goo

2014-06-01

Transepithelial bicarbonate secretion plays a key role in the maintenance of fluid and protein secretion from epithelial cells and the protection of the epithelial cell surface from various pathogens. Epithelial bicarbonate secretion is mainly under the control of cAMP and calcium signaling. While the physiological roles and molecular mechanisms of cAMP-induced bicarbonate secretion are relatively well defined, those induced by calcium signaling remain poorly understood in most epithelia. The present review summarizes the current status of knowledge on the role of calcium signaling in epithelial bicarbonate secretion. Specifically, this review introduces how cytosolic calcium signaling can increase bicarbonate secretion by regulating membrane transport proteins and how it synergizes with cAMP-induced mechanisms in epithelial cells. In addition, tissue-specific variations in the pancreas, salivary glands, intestines, bile ducts, and airways are discussed. We hope that the present report will stimulate further research into this important topic. These studies will provide the basis for future medicines for a wide spectrum of epithelial disorders including cystic fibrosis, Sjögren's syndrome, and chronic pancreatitis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Forces and dynamics in epithelial domes of controlled size and shape

NASA Astrophysics Data System (ADS)

Latorre-Ibars, Ernest; Casares, Laura; Gomez-Gonzalez, Manuel; Uroz, Marina; Arroyo, Marino; Trepat, Xavier

Mechanobiology of epithelia plays a central role in morphogenesis, wound healing, and tumor progression. Its current understanding relies on mechanical measurements on flat epithelial layers. However, most epithelia in vivo exhibit a curved 3D shape enclosing a pressurized lumen. Using soft micropatterned substrates we produce massive parallel arrays of epithelial domes with controlled size and basal shape. We measure epithelial traction, tension, and luminal pressure in epithelial domes. The local stress tensor on the freestanding epithelial membrane is then mapped by combining measured luminal pressure and local curvature. We show that tension and cell shape are highly anisotropic and vary along the meridional position of the domes. Finally, we establish constitutive relations between shape, tension, and pressure during perturbations of the contractile machinery, osmotic shocks, and spontaneous fluctuations of dome volume. Our findings contradict a description of the epithelium as a fluid capillary surface. Cells in the dome are unable to relax into a uniform and isotropic tensional state through sub- and supra-cellular rearrangements. Mapping epithelial shape, tension, and pressure will enable quantitative studies of mechanobiology in 3D epithelia of controlled size and shape.

Host-pathogen interactions in bovine mammary epithelial cells and HeLa cells by Staphylococcus aureus isolated from subclinical bovine mastitis.

PubMed

Castilho, Ivana G; Dantas, Stéfani Thais Alves; Langoni, Hélio; Araújo, João P; Fernandes, Ary; Alvarenga, Fernanda C L; Maia, Leandro; Cagnini, Didier Q; Rall, Vera L M

2017-08-01

Staphylococcus aureus is a common pathogen that causes subclinical bovine mastitis due to several virulence factors. In this study, we analyzed S. aureus isolates collected from the milk of cows with subclinical mastitis that had 8 possible combinations of bap, icaA, and icaD genes, to determine their capacity to produce biofilm on biotic (bovine primary mammary epithelial cells and HeLa cells) and abiotic (polystyrene microplates) surfaces, and their ability to adhere to and invade these cells. We also characterized isolates for microbial surface components recognizing adhesive matrix molecules (MSCRAMM) and agr genes, and for their susceptibility to cefquinome sulfate in the presence of biofilm. All isolates adhered to and invaded both cell types, but invasion indexes were higher in bovine primary mammary epithelial cells. Using tryptic soy broth + 1% glucose on abiotic surfaces, 5 out of 8 isolates were biofilm producers, but only the bap + icaA + icaD + isolate was positive in Dulbecco's Modified Eagle's medium. The production of biofilm on biotic surfaces occurred only with this isolate and only on HeLa cells, because the invasion index for bovine primary mammary epithelial cells was too high, making it impossible to use these cells in this assay. Of the 5 biofilm producers in tryptic soy broth + 1% glucose, 4 presented with the bap/fnbA/clfA/clfB/eno/fib/ebpS combination, and all were protected from cefquinome sulfate. We found no predominance of any agr group. The high invasive potential of S. aureus made it impossible to observe biofilm in bovine primary mammary epithelial cells, and we concluded that cells with lower invasion rates, such as HeLa cells, were more appropriate for this assay. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Human Skin Is the Largest Epithelial Surface for Interaction with Microbes.

PubMed

Gallo, Richard L

2017-06-01

Human skin contains an abundant and diverse population of microbial organisms. Many of these microbes inhabit follicular structures of the skin. Furthermore, numerous studies have shown that the interaction of some members of the skin microbiome with host cells will result in changes in cell function. However, estimates of the potential for the microbiome to influence human health through skin have ignored the inner follicular surface, and therefore vastly underestimated the potential of the skin microbiome to have a systemic effect on the human body. By calculating the surface area of follicular and the interfollicular epithelial surface it is shown that skin provides a vast interface for interactions with the microbiome. Copyright © 2017 The Author. Published by Elsevier Inc. All rights reserved.

Paradigm Shift in the Management Strategy for Epithelial Ovarian Cancer.

PubMed

Fujiwara, Keiichi; McAlpine, Jessica N; Lheureux, Stephanie; Matsumura, Noriomi; Oza, Amit M

2016-01-01

The hypothesis on the pathogenesis of epithelial ovarian cancer continues to evolve. Although epithelial ovarian cancer had been assumed to arise from the coelomic epithelium of the ovarian surface, it is now becoming clearer that the majority of serous carcinomas arise from epithelium of the distal fallopian tube, whereas clear cell and endometrioid cancers arise from endometriosis. Molecular and genomic characteristics of epithelial ovarian cancer have been extensively investigated. Our understanding of pathogenesis of the various histologic types of ovarian cancer have begun to inform changes to the strategies for management of epithelial ovarian cancer, which represent a paradigm shift not only for treatment but also for prevention, which previously had not been considered achievable. In this article, we will discuss novel attempts at the prevention of high-grade serous ovarian cancer and treatment strategies for two distinct entities in epithelial ovarian cancer: low-grade serous and clear cell ovarian carcinomas, which are relatively rare and resistant to conventional chemotherapy.

Gap Junction Protein Connexin 43 Serves as a Negative Marker for a Stem Cell-Containing Population of Human Limbal Epithelial Cells

PubMed Central

Chen, Zhuo; Evans, W. Howard; Pflugfelder, Stephen C.; Li, De-Quan

2010-01-01

This study evaluated whether the gap junction protein connexin (Cx) 43 could serve as a negative cell surface marker for human corneal epithelial stem cells. Cx43 expression was evaluated in corneo-limbal tissue and primary limbal epithelial cultures. Immunofluorescent staining and laser scanning confocal microscopy showed that Cx43 was strongly expressed in the corneal and limbal suprabasal epithelial cells, but the basal cells of the limbal epithelium were negative. Cx43 antibody stained mainly large cells but not small cells in primary limbal epithelial cultures. As determined by semiquantitative reverse transcription polymerase chain reaction (PCR) and real-time PCR, Cx43 mRNA was more abundant in the corneal than limbal epithelia, and it was expressed in higher levels in mature limbal epithelial cultures. Using GAP11, a rabbit polyclonal antibody against the Cx32 extracellular loop 2 (151–187), a sequence that is highly homologous in Cx43, the Cx43dim and Cx43bright cells were selected from primary limbal epithelial cultures by fluorescence-activated cell sorting and were evaluated for stem cell properties. These Cx43dim and Cx43bright cells were confirmed by their expression levels of Cx43 protein and mRNA. The Cx43dim cells were found to contain higher percentages of slow-cycling bromodeoxyuridine (BrdU)-label retaining cells and the cells that were positive for stem cell-associated markers p63, ABCG2, and integrin β1 and negative for differentiation markers K3 and involucrin. The Cx43dim cells possessed a greater proliferative potential than Cx43bright cells and nonfractionated cells as evaluated by BrdU incorporation, colony-forming efficiency, and growth capacity. Our findings suggest that human limbal basal cells do not express connexin 43, which could serve as a negative cell surface marker for the stem cell-containing population of human limbal epithelial cells. PMID:16424398

The Interplay between Entamoeba and Enteropathogenic Bacteria Modulates Epithelial Cell Damage

PubMed Central

Galván-Moroyoqui, José Manuel; Domínguez-Robles, M. del Carmen; Franco, Elizabeth; Meza, Isaura

2008-01-01

Background Mixed intestinal infections with Entamoeba histolytica, Entamoeba dispar and bacteria with exacerbated manifestations of disease are common in regions where amoebiasis is endemic. However, amoeba–bacteria interactions remain largely unexamined. Methodology Trophozoites of E. histolytica and E. dispar were co-cultured with enteropathogenic bacteria strains Escherichia coli (EPEC), Shigella dysenteriae and a commensal Escherichia coli. Amoebae that phagocytosed bacteria were tested for a cytopathic effect on epithelial cell monolayers. Cysteine proteinase activity, adhesion and cell surface concentration of Gal/GalNAc lectin were analyzed in amoebae showing increased virulence. Structural and functional changes and induction of IL-8 expression were determined in epithelial cells before and after exposure to bacteria. Chemotaxis of amoebae and neutrophils to human IL-8 and conditioned culture media from epithelial cells exposed to bacteria was quantified. Principal Findings E. histolytica digested phagocytosed bacteria, although S. dysenteriae retained 70% viability after ingestion. Phagocytosis of pathogenic bacteria augmented the cytopathic effect of E. histolytica and increased expression of Gal/GalNAc lectin on the amoebic surface and increased cysteine proteinase activity. E. dispar remained avirulent. Adhesion of amoebae and damage to cells exposed to bacteria were increased. Additional increases were observed if amoebae had phagocytosed bacteria. Co-culture of epithelial cells with enteropathogenic bacteria disrupted monolayer permeability and induced expression of IL-8. Media from these co-cultures and human recombinant IL-8 were similarly chemotactic for neutrophils and E. histolytica. Conclusions Epithelial monolayers exposed to enteropathogenic bacteria become more susceptible to E. histolytica damage. At the same time, phagocytosis of pathogenic bacteria by amoebae further increased epithelial cell damage. Significance The in vitro system presented here provides evidence that the Entamoeba/enteropathogenic bacteria interplay modulates epithelial cell responses to the pathogens. In mixed intestinal infections, where such interactions are possible, they could influence the outcome of disease. The results offer insights to continue research on this phenomenon. PMID:18648517

Isolation, immortalization, and characterization of a human breast epithelial cell line with stem cell properties

PubMed Central

Gudjonsson, Thorarinn; Villadsen, René; Nielsen, Helga Lind; Rønnov-Jessen, Lone; Bissell, Mina J.; Petersen, Ole William

2002-01-01

The epithelial compartment of the human breast comprises two distinct lineages: the luminal epithelial and the myoepithelial lineage. We have shown previously that a subset of the luminal epithelial cells could convert to myoepithelial cells in culture signifying the possible existence of a progenitor cell. We therefore set out to identify and isolate the putative precursor in the luminal epithelial compartment. Using cell surface markers and immunomagnetic sorting, we isolated two luminal epithelial cell populations from primary cultures of reduction mammoplasties. The major population coexpresses sialomucin (MUC+) and epithelial-specific antigen (ESA+) whereas the minor population has a suprabasal position and expresses epithelial specific antigen but no sialomucin (MUC−/ESA+). Two cell lines were further established by transduction of the E6/E7 genes from human papilloma virus type 16. Both cell lines maintained a luminal epithelial phenotype as evidenced by expression of the tight junction proteins, claudin-1 and occludin, and by generation of a high transepithelial electrical resistance on semipermeable filters. Whereas in clonal cultures, the MUC+/ESA+ epithelial cell line was luminal epithelial restricted in its differentiation repertoire, the suprabasal-derived MUC−/ESA+ epithelial cell line was able to generate itself as well as MUC+/ESA+ epithelial cells and Thy-1+/α-smooth muscle actin+ (ASMA+) myoepithelial cells. The MUC−/ESA+ epithelial cell line further differed from the MUC+/ESA+ epithelial cell line by the expression of keratin K19, a feature of a subpopulation of epithelial cells in terminal duct lobular units in vivo. Within a reconstituted basement membrane, the MUC+/ESA+ epithelial cell line formed acinus-like spheres. In contrast, the MUC−/ESA+ epithelial cell line formed elaborate branching structures resembling uncultured terminal duct lobular units both by morphology and marker expression. Similar structures were obtained by inoculating the extracellular matrix-embedded cells subcutaneously in nude mice. Thus, MUC−/ESA+ epithelial cells within the luminal epithelial lineage may function as precursor cells of terminal duct lobular units in the human breast. PMID:11914275

Results of the clinical examination of an ointment with marigold (Calendula officinalis) extract in the treatment of venous leg ulcers.

PubMed

Duran, V; Matic, M; Jovanovć, M; Mimica, N; Gajinov, Z; Poljacki, M; Boza, P

2005-01-01

The aim of this study was to determine the therapeutic efficacy of marigold (Calendula officinalis) extract on the epithelialization of lower leg venous ulcers. The experiment was carried out in 34 patients with venous leg ulcers. The patients were divided into two groups. In the first (experimental) group, patients were treated with an ointment containing marigold extract, which was prepared in an apparatus devised by Soxleth and was incorporated into a neutral base. Twenty-one patients with 33 venous ulcers were treated. Therapy was applied twice a day for 3 weeks. The second group was a control group that consisted of 13 patients with 22 venous ulcers. In the control group, saline solution dressings were applied to ulcers for 3 weeks. In the experimental group the total surface of all the ulcers at the beginning of the therapy was 67,544 mm2. After the third week the total surface of all the ulcers was 39,373 mm2 (a decrease of 41.71%). In seven patients, complete epithelialization was achieved. In the control group the total surface of all the ulcers at the beginning of the therapy was 69,722 mm2. After the third week the total surface of all the ulcers was 58,743 mm2 (a decrease of 14.52%). In four patients, complete epithelialization was achieved. There was a statistically significant acceleration of wound healing in the experimental group (p < 0.05). The results obtained are preliminary, but they suggest the positive effects of the ointment with marigold extract on venous ulcer epithelialization.

Investigating the Link between Molecular Subtypes of Glioblastoma, Epithelial-Mesenchymal Transition, and CD133 Cell Surface Protein

PubMed Central

Zarkoob, Hadi; Taube, Joseph H.; Singh, Sheila K.; Mani, Sendurai A.; Kohandel, Mohammad

2013-01-01

In this manuscript, we use genetic data to provide a three-faceted analysis on the links between molecular subclasses of glioblastoma, epithelial-to-mesenchymal transition (EMT) and CD133 cell surface protein. The contribution of this paper is three-fold: First, we use a newly identified signature for epithelial-to-mesenchymal transition in human mammary epithelial cells, and demonstrate that genes in this signature have significant overlap with genes differentially expressed in all known GBM subtypes. However, the overlap between genes up regulated in the mesenchymal subtype of GBM and in the EMT signature was more significant than other GBM subtypes. Second, we provide evidence that there is a negative correlation between the genetic signature of EMT and that of CD133 cell surface protein, a putative marker for neural stem cells. Third, we study the correlation between GBM molecular subtypes and the genetic signature of CD133 cell surface protein. We demonstrate that the mesenchymal and neural subtypes of GBM have the strongest correlations with the CD133 genetic signature. While the mesenchymal subtype of GBM displays similarity with the signatures of both EMT and CD133, it also exhibits some differences with each of these signatures that are partly due to the fact that the signatures of EMT and CD133 are inversely related to each other. Taken together these data shed light on the role of the mesenchymal transition and neural stem cells, and their mutual interaction, in molecular subtypes of glioblastoma multiforme. PMID:23734191

Large Extremity Peripheral Nerve Repair

DTIC Science & Technology

2014-10-01

has also been shown to produce human-beta-3-defensin. These antimicrobial peptides are implicated in the resistance of epithelial surfaces to...gonadotrophin receptors that regulate prostaglandin production and activity. Epithelial cells manufacture multiple vasoactive peptides , growth factors...200734 P-RCT (n Z 102) PT burns Processed Amnion vs topical antimicrobials . Significantly less dressing changes with amnion. Time to healing, length

JPRS Report, Science & Technology, USSR: Life Sciences

DTIC Science & Technology

1990-12-10

Kostyuchenko; VECHERNYAYA MOSKVA, 29 Aug 90] 16 First Results and Objectives of Investigation of Lyme Disease in the USSR [ E . I. Korenberg, V . N...89) pp 993-996 [Article by M. A. Bundule, V . V . Bychko, Yu. B. Saulitis, E . E . Liyepinsh, G. P. Borisova, I. A. Petrovskiy, V . V . Tsibinogin, P. P...Pushko, V . P. Ose, D. E . Dreylinya, P. P. Pumpen, and E . Ya. Gren, corresponding member, Organic Synthesis Institute, Latvian SSR Academy of JPRS-ULS

Notch Signaling Modulates MUC16 Biosynthesis in an In Vitro Model of Human Corneal and Conjunctival Epithelial Cell Differentiation

PubMed Central

Xiong, Linjie; Woodward, Ashley M.

2011-01-01

Purpose. Notch proteins are a family of transmembrane receptors that coordinate binary cell fate decisions and differentiation in wet-surfaced epithelia. We sought to determine whether Notch signaling contributes to maintaining mucosal homeostasis by modulating the biosynthesis of cell surface-associated mucins in an in vitro model of human corneal (HCLE) and conjunctival (HCjE) epithelial cell differentiation. Methods. HCLE and HCjE cells were grown at different stages of differentiation, representing nondifferentiated (preconfluent and confluent) and differentiated (stratified) epithelial cultures. Notch signaling was blocked with the γ-secretase inhibitor dibenzazepine (DBZ). The presence of Notch intracellular domains (Notch1 to Notch3) and mucin protein (MUC1, -4, -16) was evaluated by electrophoresis and Western blot analysis. Mucin gene expression was determined by TaqMan real-time polymerase chain reaction. Results. Here we demonstrate that Notch3 is highly expressed in undifferentiated and differentiated HCLE and HCjE cells, and that Notch1 and Notch2 biosynthesis is enhanced by induction of differentiation with serum-containing media. Inhibition of Notch signaling with DBZ impaired MUC16 biosynthesis in a concentration-dependent manner in undifferentiated cells at both preconfluent and confluent stages, but not in postmitotic stratified cells. In contrast to protein levels, the amount of MUC16 transcripts were not significantly reduced after DBZ treatment, suggesting that Notch regulates MUC16 posttranscriptionally. Immunoblots of DBZ-treated epithelial cells grown at different stages of differentiation revealed no differences in the levels of MUC1 and MUC4. Conclusions. These results indicate that MUC16 biosynthesis is posttranscriptionally regulated by Notch signaling at early stages of epithelial cell differentiation, and suggest that Notch activation contributes to maintaining a mucosal phenotype at the ocular surface. PMID:21508102

Atheroprotective immunization with malondialdehyde-modified LDL is hapten specific and dependent on advanced MDA adducts: implications for development of an atheroprotective vaccine1[S

PubMed Central

Gonen, Ayelet; Hansen, Lotte F.; Turner, William W.; Montano, Erica N.; Que, Xuchu; Rafia, Apaїs; Chou, Meng-Yun; Wiesner, Philipp; Tsiantoulas, Dimitrios; Corr, Maripat; VanNieuwenhze, Michael S.; Tsimikas, Sotirios; Binder, Christoph J.; Witztum, Joseph L.; Hartvigsen, Karsten

2014-01-01

Immunization with homologous malondialdehyde (MDA)-modified LDL (MDA-LDL) leads to atheroprotection in experimental models supporting the concept that a vaccine to oxidation-specific epitopes (OSEs) of oxidized LDL could limit atherogenesis. However, modification of human LDL with OSE to use as an immunogen would be impractical for generalized use. Furthermore, when MDA is used to modify LDL, a wide variety of related MDA adducts are formed, both simple and more complex. To define the relevant epitopes that would reproduce the atheroprotective effects of immunization with MDA-LDL, we sought to determine the responsible immunodominant and atheroprotective adducts. We now demonstrate that fluorescent adducts of MDA involving the condensation of two or more MDA molecules with lysine to form malondialdehyde-acetaldehyde (MAA)-type adducts generate immunodominant epitopes that lead to atheroprotective responses. We further demonstrate that a T helper (Th) 2-biased hapten-specific humoral and cellular response is sufficient, and thus, MAA-modified homologous albumin is an equally effective immunogen. We further show that such Th2-biased humoral responses per se are not atheroprotective if they do not target relevant antigens. These data demonstrate the feasibility of development of a small-molecule immunogen that could stimulate MAA-specific immune responses, which could be used to develop a vaccine approach to retard or prevent atherogenesis. PMID:25143462

Using EFSO/PQC to Improve the Quality of Observations and Analyses

NASA Astrophysics Data System (ADS)

Chen, T. C.; Kalnay, E.

2017-12-01

Massive amounts of observations are assimilated every day into modern Numerical Weather Prediction (NWP) systems. This makes difficult to estimate the impact of a new observing system using the current approach (Observing System Experiments, OSEs) because there is already so much information provided by existing observations. In addition, the large volume of data also prevents monitoring the impact of each assimilated observation with OSEs. We demonstrate here how using Ensemble Forecast Sensitivity to Observations (EFSO) allows monitoring and improving the impact of observations on the analyses and forecasts in the Hybrid GSI/LETKF system. In addition, we show how EFSO can identify flow dependent detrimental observations from observing systems that, on the average, are beneficial. For example, using EFSO we find that positive zonal wind innovations in MODIS polar winds are generally detrimental, whereas no such bias is present in other satellite wind systems. We also show how EFSO can be used to identify and reject very detrimental observations (Proactive Quality Control, PQC). The withdrawal of these detrimental observations leads to improved analyses and 5-day forecasts, which also serves as a verification of EFSO. The operational implementation of PQC/EFSO is computationally very feasible, and will provide detailed QC monitoring of every observing system. Finally, we provide a theoretical justification of the PQC and its connection to dynamical instabilities with a simple Lorenz 96 model.

Membrane proteins follow multiple pathways to the basolateral cell surface in polarized epithelial cells

PubMed Central

Farr, Glen A.; Hull, Michael; Mellman, Ira

2009-01-01

Newly synthesized apical and basolateral membrane proteins are sorted from one another in polarized epithelial cells. The trans-Golgi network participates in this sorting process, but some basolateral proteins travel from the Golgi to recycling endosomes (REs) before their surface delivery. Using a novel system for pulse–chase microscopy, we have visualized the postsynthetic route pursued by a newly synthesized cohort of Na,K-ATPase. We find that the basolateral delivery of newly synthesized Na,K-ATPase occurs via a pathway distinct from that pursued by the vesicular stomatitis virus G protein (VSV-G). Na,K-ATPase surface delivery occurs at a faster rate than that observed for VSV-G. The Na,K-ATPase does not pass through the RE compartment en route to the plasma membrane, and Na,K-ATPase trafficking is not regulated by the same small GTPases as other basolateral proteins. Finally, Na,K-ATPase and VSV-G travel in separate post-Golgi transport intermediates, demonstrating directly that multiple routes exist for transport from the Golgi to the basolateral membrane in polarized epithelial cells. PMID:19620635

Human Corneal Limbal-Epithelial Cell Response to Varying Silk Film Geometric Topography In Vitro

PubMed Central

Lawrence, Brian D.; Pan, Zhi; Liu, Aihong; Kaplan, David L.; Rosenblatt, Mark I.

2012-01-01

Silk fibroin films are a promising class of biomaterials that have a number of advantages for use in ophthalmic applications due to their transparent nature, mechanical properties and minimal inflammatory response upon implantation. Freestanding silk films with parallel line and concentric ring topographies were generated for in vitro characterization of human corneal limbal-epithelial (HCLE) cell response upon differing geometric patterned surfaces. Results indicated that silk film topography significantly affected initial HCLE culture substrate attachment, cellular alignment, cell-to-cell contact formation, actin cytoskeleton alignment, and focal adhesion (FA) localization. Most notably, parallel line patterned surfaces displayed a 36%–54% increase on average in initial cell attachment, which corresponded to an over 2-fold increase in FA localization when compared to other silk film surfaces and controls. In addition, distinct localization of FA formation was observed along the edges for all patterned silk film topographies. In conclusion, silk film feature topography appears to help direct corneal epithelial cell response and cytoskeleton development, especially in regards to FA distribution, in vitro. PMID:22705042

Structural changes of oviduct of freshwater shrimp, Macrobrachium nipponense (Decapoda, Palaemonidae), during spawning*

PubMed Central

Lu, Jian-ping; Zhang, Xiao-hui; Yu, Xiao-yun

2006-01-01

The structural change of the oviduct of freshwater shrimp (Macrobrachium nipponense) during spawning was examined by electron microscopy. The oviduct wall structural characteristics seem to be influenced significantly by the spawning process. Before the parturition and ovulation, two types of epithelial cells (types I and II) are found in the epithelium. The free surfaces of type I and type II cells have very dense long microvilli. Under the type I and type II cells, are a relatively thick layer of secreting material and a layer of mostly dead cells. After ovulation, two other types of epithelial cells (types III and IV) are found in the oviduct wall epithelium. The free surface of type III cells only has short microvilli scattered on the surface. The thick layer with secreting material and the dead cell layer disappeared at this stage. In some type III cells, the leaking out of cytoplasm from broken cell membrane led to the death of these type III cells. The transformation of all four types of epithelial cells was in the order: IV→I→II→III. PMID:16365928

Potential Role of Induced Pluripotent Stem Cells (IPSCs) for Cell-Based Therapy of the Ocular Surface

PubMed Central

Casaroli-Marano, Ricardo P.; Nieto-Nicolau, Núria; Martínez-Conesa, Eva M.; Edel, Michael; Álvarez-Palomo, Ana B.

2015-01-01

The integrity and normal function of the corneal epithelium are crucial for maintaining the cornea’s transparency and vision. The existence of a cell population with progenitor characteristics in the limbus maintains a dynamic of constant epithelial repair and renewal. Currently, cell-based therapies for bio replacement—cultured limbal epithelial transplantation (CLET) and cultured oral mucosal epithelial transplantation (COMET)—present very encouraging clinical results for treating limbal stem cell deficiency (LSCD) and restoring vision. Another emerging therapeutic approach consists of obtaining and implementing human progenitor cells of different origins in association with tissue engineering methods. The development of cell-based therapies using stem cells, such as human adult mesenchymal or induced pluripotent stem cells (IPSCs), represent a significant breakthrough in the treatment of certain eye diseases, offering a more rational, less invasive, and better physiological treatment option in regenerative medicine for the ocular surface. This review will focus on the main concepts of cell-based therapies for the ocular surface and the future use of IPSCs to treat LSCD. PMID:26239129

A fish eye out of water: epithelial surface projections on aerial and aquatic corneas of the 'four-eyed fish' Anableps anableps.

PubMed

Simmich, Joshua; Temple, Shelby E; Collin, Shaun P

2012-03-01

Vertebrate corneas feature a variety of microprojections, to which a tear film adheres. These microprojections are formed by folds in epithelial cell membranes, which increase surface area, stabilise the tear film and enhance movement of nutritional and waste products across cell membranes. Differences in corneal microprojections among vertebrates have been correlated with habitat and differ markedly between terrestrial and aquatic species. This study investigated epithelial microprojections of both the aerial (dorsal) and aquatic (ventral) corneal surfaces of the 'four-eyed fish' Anableps anableps using scanning electron microscopy. The central region of the dorsal cornea, which projects above the water, had a density of 16,387 ± 3,995 cells per mm(2) , while the central region of the ventral cornea (underwater) had a density of 22,428 ± 6,387 cells per mm(2), a difference that suggests an environmental adaptation along the two visual axes. Both corneal surfaces were found to possess microridges rather than microvilli or microplicae characteristic of terrestrial/aerial vertebrates. Microridges were 142 ± 9 nm wide and did not differ (p = 0.757) between dorsal and ventral corneas. Microridges were consistently separated by a distance of 369 ± 9 nm across both corneas. Dorsal-ventral differences in corneal epithelial cell density in Anableps anableps suggest a difference in osmotic pressure of the two corneas. The modest differences in the microprojections indicate that the need to secure the tear film underlying each optical axis is of prime importance, due to the likelihood that a persistent layer of water normally covers both dorsal and ventral corneal surfaces and that maintaining a transparent optical pathway for vision is critical for a species prone to predation from both above and below the water's surface. © 2012 The Authors. Clinical and Experimental Optometry © 2012 Optometrists Association Australia.

γδ T cells in homeostasis and host defence of epithelial barrier tissues.

PubMed

Nielsen, Morten M; Witherden, Deborah A; Havran, Wendy L

2017-12-01

Epithelial surfaces line the body and provide a crucial interface between the body and the external environment. Tissue-resident epithelial γδ T cells represent a major T cell population in the epithelial tissues and are ideally positioned to carry out barrier surveillance and aid in tissue homeostasis and repair. In this Review, we focus on the intraepithelial γδ T cell compartment of the two largest epithelial tissues in the body - namely, the epidermis and the intestine - and provide a comprehensive overview of the crucial contributions of intraepithelial γδ T cells to tissue integrity and repair, host homeostasis and protection in the context of the symbiotic relationship with the microbiome and during pathogen clearance. Finally, we describe epithelium-specific butyrophilin-like molecules and briefly review their emerging role in selectively shaping and regulating epidermal and intestinal γδ T cell repertoires.

Cell death at the intestinal epithelial front line.

PubMed

Delgado, Maria Eugenia; Grabinger, Thomas; Brunner, Thomas

2016-07-01

The intestinal epithelium represents the largest epithelial surface in our body. This single-cell-layer epithelium mediates important functions in the absorption of nutrients and in the maintenance of barrier function, preventing luminal microorganisms from invading the body. Due to its constant regeneration the intestinal epithelium is a tissue not only with very high proliferation rates but also with very prominent physiological and pathophysiological cell death induction. The normal physiological differentiation and maturation of intestinal epithelial cells leads to their shedding and apoptotic cell death within a few days, without disturbing the epithelial barrier integrity. In contrast excessive intestinal epithelial cell death induced by irradiation, drugs and inflammation severely impairs the vital functions of this tissue. In this review we discuss cell death processes in the intestinal epithelium in health and disease, with special emphasis on cell death triggered by the tumour necrosis factor receptor family. © 2015 FEBS.

A high resolution study of the glycocalyx of rat uterine epithelial cells during early pregnancy with the field emission gun scanning electron microscope.

PubMed Central

Jones, B J; Murphy, C R

1994-01-01

The field emission gun scanning electron microscope has been used to investigate morphological changes at the macromolecular level in the glycocalyx of rat uterine luminal epithelial cells during early pregnancy. This very high resolution microscope has allowed visualisation at a level previously unobtainable and has enabled us to establish that dramatic alterations occur in this glycocalyx at the time of blastocyst attachment. On d 1 of pregnancy a prominent, filamentous glycocalyx radiates from the microvilli. However, by d 6 of pregnancy when the microvilli have been replaced by irregular cell surface protrusions, the glycocalyceal filaments are completely lost and the plasma membrane appears smooth and covered with a felt-like coating. These morphological observations suggest a major reorganisation in surface carbohydrates during early pregnancy and extend histochemical observations on the uterine epithelial glycocalyx. Images Fig. 1 Fig. 2 Figs. 3 and 4 PMID:7961152

Fatal winter dysentery with severe anemia in an adult cow.

PubMed

Natsuaki, Sumiko; Goto, Keiichi; Nakamura, Kikuyasu; Yamada, Manabu; Ueo, Hiroshi; Komori, Toshihiro; Shirakawa, Hitomi; Uchinuno, Yukinori

2007-09-01

An adult dairy cow fatally affected with winter dysentery was investigated pathologically and virologically. The cow had severe anemia and diarrhea with massive blood. Pathologically, the loss of surface epithelial cells and necrosis of crypt epithelial cells in the large intestine were observed. Bovine coronavirus (BCV) antigen was observed in necrotic crypt epithelial cells of the large intestine. Virus particles were found in the necrotic epithelial cells of the large intestine. Virologically, BCV was isolated from the feces of the dead cow. The dead cow had no serum antibody against BCV although the co-habitants did. These suggest that severe infection of BCV in the cow without the BCV antibody accompanied by severe hemorrhagic anemia resulted in the cow's death.

Jet Stream Analysis and Forecast Errors Using GADS Aircraft Observations in the DAO, ECMWF, and NCEP Models

NASA Technical Reports Server (NTRS)

Cardinali, Carla; Rukhovets, Leonid; Tenenbaum, Joel

2003-01-01

We have utilized an extensive set of independent British Airways flight data recording wind vector and temperature observations (the Global Aircraft Data Set [GADS] archive) in three ways: (a) as an independent check of operational analyses; (b) as an analysis observing system experiment (OSE) as if the GADS observations were available in real time; and (c) as the corresponding forecast simulation experiment applicable to future operational forecasts. Using a 31 day sample (0000 UTC 20 December 2000 through 0000 UTC 20 January 2000) from Winter 2000, we conclude that over the data-dense continental U. S. analyzed jet streaks are too weak by -2% to -5%. Over nearby data-sparse regions of Canada, analyzed jet streaks are too weak by -5% to -9%. The second range provides a limit on the accuracy of current jet streak analyses over the portions of the -85% of the earth's surface that are poorly covered by non-satellite observations. The -5% to -9% range is relevant for the pre-third generation satellite (AIRS, IASI, GIFTS) era.

Nacre formation by epithelial cell cultures from mantle of the black-lip pearl oyster, Pinctada margaritifera.

PubMed

Jayasankar, Vidya; Vasudevan, Srinivasa Raghavan; Poulose, Suja C; Divipala, Indira

2018-06-12

Mantle tissue from the black-lip pearl oyster, Pinctada margaritifera, was cultured in vitro using sterilized seawater supplemented with 0.1% yeast extract as the culture medium. Granular and agranular epithelial cells, hyalinocytes, and fibroblast-like cells were observed in the initial stages of culture. Epithelial cells later formed pseudopodial cell networks containing clusters of granulated cells, which upon maturation released their colored granules. These granules induced formation of nacre crystal deposits on the bottom of the culture plate. Cultures comprised of only granulated epithelial cells were established through periodic sub-culturing of mantle cells and maintained for over 18 mo in a viable condition. Reverse transcriptase PCR of cultured cells demonstrated gene expression of the shell matrix protein, nacrein. To further evaluate the functional ability of cultured granulated epithelial cells, nuclear shell beads were incubated in culture medium containing these cells to induce nacre formation on the beads. Observation of the bead surface under a stereomicroscope at periodic intervals showed the gradual formation of blackish yellow colored nacre deposits. Examination of the bead surface by scanning electron microscopy and energy dispersive X-ray analysis at periodic intervals revealed a distinct brick and mortar formation characteristic of nacre, comprised of aragonite platelets and matrix proteins. Calcium, carbon, and oxygen were the major elements in all stages examined. Our study shows that mantle epithelial cells in culture retain the ability to secrete nacre and can therefore form the basis for future studies on the biomineralization process and its application in development of sustainable pearl culture.

Inflammation and Disintegration of Intestinal Villi in an Experimental Model for Vibrio parahaemolyticus-Induced Diarrhea

PubMed Central

Ritchie, Jennifer M.; Rui, Haopeng; Zhou, Xiaohui; Iida, Tetsuya; Kodoma, Toshio; Ito, Susuma; Davis, Brigid M.; Bronson, Roderick T.; Waldor, Matthew K.

2012-01-01

Vibrio parahaemolyticus is a leading cause of seafood-borne gastroenteritis in many parts of the world, but there is limited knowledge of the pathogenesis of V. parahaemolyticus-induced diarrhea. The absence of an oral infection-based small animal model to study V. parahaemolyticus intestinal colonization and disease has constrained analyses of the course of infection and the factors that mediate it. Here, we demonstrate that infant rabbits oro-gastrically inoculated with V. parahaemolyticus develop severe diarrhea and enteritis, the main clinical and pathologic manifestations of disease in infected individuals. The pathogen principally colonizes the distal small intestine, and this colonization is dependent upon type III secretion system 2. The distal small intestine is also the major site of V. parahaemolyticus-induced tissue damage, reduced epithelial barrier function, and inflammation, suggesting that disease in this region of the gastrointestinal tract accounts for most of the diarrhea that accompanies V. parahaemolyticus infection. Infection appears to proceed through a characteristic sequence of steps that includes remarkable elongation of microvilli and the formation of V. parahaemolyticus-filled cavities within the epithelial surface, and culminates in villus disruption. Both depletion of epithelial cell cytoplasm and epithelial cell extrusion contribute to formation of the cavities in the epithelial surface. V. parahaemolyticus also induces proliferation of epithelial cells and recruitment of inflammatory cells, both of which occur before wide-spread damage to the epithelium is evident. Collectively, our findings suggest that V. parahaemolyticus damages the host intestine and elicits disease via previously undescribed processes and mechanisms. PMID:22438811

EMMPRIN modulates epithelial barrier function through a MMP-mediated occludin cleavage: implications in dry eye disease.

PubMed

Huet, Eric; Vallée, Benoit; Delbé, Jean; Mourah, Samia; Prulière-Escabasse, Virginie; Tremouilleres, Magali; Kadomatsu, Kenji; Doan, Serge; Baudouin, Christophe; Menashi, Suzanne; Gabison, Eric E

2011-09-01

Dry eye is a common disease that develops as a result of alteration of tear fluid, leading to osmotic stress and a perturbed epithelial barrier. Matrix metalloproteinase-9 (MMP-9) may be important in dry eye disease, as its genetic knockout conferred resistance to the epithelial disruption. We show that extracellular matrix metalloproteinase inducer (EMMPRIN; also termed CD147), an inducer of MMP expression, participates in the pathogenesis of dry eye through MMP-mediated cleavage of occludin, an important component of tight junctions. EMMPRIN expression was increased on the ocular surface of dry eye patients and correlated with those of MMP-9. High osmolarity in cell culture, mimicking dry eye conditions, increased both EMMPRIN and MMP-9 and resulted in the disruption of epithelial junctions through the cleavage of occludin. Exogenously added recombinant EMMPRIN had similar effects that were abrogated in the presence of the MMP inhibitor marimastat. Membrane occludin immunostaining was markedly increased in the apical corneal epithelium of both EMMPRIN and MMP-9 knock-out mice. Furthermore, an inverse correlation between EMMPRIN and occludin membrane staining was consistently observed both in vitro and in vivo as a function of corneal epithelial cells differentiation. These data suggest a possible role of EMMPRIN in regulating the amount of occludin at the cell surface in homeostasis beyond pathological situations such as dry eye disease, and EMMPRIN may be essential for the formation and maintenance of organized epithelial structure. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Rebamipide increases the mucin-like glycoprotein production in corneal epithelial cells.

PubMed

Takeji, Yasuhiro; Urashima, Hiroki; Aoki, Akihiro; Shinohara, Hisashi

2012-06-01

Dry eye is a multifactorial disease of tears and the ocular surface due to tear deficiency or excessive tear evaporation. Tear film instability is due to a disturbance in ocular surface mucin leading to a dysfunction of mucin, resulting in dry eye. In this study, we examined the effect of rebamipide, an anti-ulcer agent, on glycoconjugate production, as an indicator of mucin-like glycoprotein in cultured corneal epithelial cells. Further, we investigated the effect of rebamipide on the gene expression of membrane-associated mucins. Confluent cultured human corneal epithelial cells were incubated with rebamipide for 24 h. The glycoconjugate content in the supernatant and the cell extracts was measured by wheat germ agglutinin-enzyme-linked lectin assay combined gel-filtration method. In the experiment on mucin gene expression, cultured human corneal epithelial cells were collected at 0, 3, 6, and 12 h after administration of rebamipide. Real-time quantitative polymerase chain reaction was used to analyze the quantity of MUC1, MUC 4, and MUC16 gene expression. Rebamipide significantly increased the glycoconjugate contents in the supernatant and cell extract. In the mucin gene expression in the cells, rebamipide increased MUC1 and MUC4 gene expression, but did not increase MUC16 gene expression. Rebamipide promoted glycoconjugate, which has a property as a mucin-like glycoprotein, in human corneal epithelial cells. The increased production was mediated by MUC1 and MUC4 gene expression.

Sutureless amniotic membrane transplantation for partial limbal stem cell deficiency.

PubMed

Kheirkhah, Ahmad; Casas, Victoria; Raju, Vadrevu K; Tseng, Scheffer C G

2008-05-01

To evaluate the results of sutureless amniotic membrane (AM) transplantation using fibrin glue for reconstructing corneal surfaces with partial limbal stem cell deficiency (LSCD). Retrospective noncomparative interventional case series. Eleven eyes of nine patients that had LSCD with 120 degrees to almost 360 degrees of limbal involvement underwent superficial keratectomy to remove the conjunctivalized pannus followed by AM transplantation using fibrin glue. Additional sutureless AM patch (ProKera; Bio-Tissue, Inc, Miami, Florida, USA) was used in seven patients, and mitomycin C was applied on the cornea in four eyes and during fornix reconstruction in seven eyes. The surgery was repeated in three eyes for residual pannus. During a mean follow-up of 14.2 +/- 7.7 months (range, six to 26 months), all eyes maintained a smooth and stable corneal epithelial surface without recurrent erosion or persistent epithelial defect, and showed less stromal cloudiness and vascularization. Best-corrected visual acuity improved in nine eyes (81.8%). Corneal epithelialization proceeded by epithelial growth over AM (n = 4), accompanied by dissolution of AM (n = 4) or a combination of both (n = 3). No complication was noted regarding initial or repeated uses of fibrin glue. AM transplantation using fibrin glue appears to be a safe and effective method of restoring a stable corneal epithelium for cases with partial LSCD. This approach avoids the need of transplanting limbal epithelial stem cells.

Development of a wide-field fluorescence imaging system for evaluation of wound re-epithelialization

NASA Astrophysics Data System (ADS)

Franco, Walfre; Gutierrez-Herrera, Enoch; Purschke, Martin; Wang, Ying; Tam, Josh; Anderson, R. Rox; Doukas, Apostolos

2013-03-01

Normal skin barrier function depends on having a viable epidermis, an epithelial layer formed by keratinocytes. The transparent epidermis, which is less than a 100 mum thick, is nearly impossible to see. Thus, the clinical evaluation of re-epithelialization is difficult, which hinders selecting appropriate therapy for promoting wound healing. An imaging system was developed to evaluate epithelialization by detecting endogenous fluorescence emissions of cellular proliferation over a wide field of view. A custom-made 295 nm ultraviolet (UV) light source was used for excitation. Detection was done by integrating a near-UV camera with sensitivity down to 300 nm, a 12 mm quartz lens with iris and focus lock for the UV regime, and a fluorescence bandpass filter with 340 nm center wavelength. To demonstrate that changes in fluorescence are related to cellular processes, the epithelialization of a skin substitute was monitored in vitro. The skin substitute or construct was made by embedding microscopic live human skin tissue columns, 1 mm in diameter and spaced 1 mm apart, in acellular porcine dermis. Fluorescence emissions clearly delineate the extent of lateral surface migration of keratinocytes and the total surface covered by the new epithelium. The fluorescence image of new epidermis spatially correlates with the corresponding color image. A simple, user-friendly way of imaging the presence of skin epithelium would improve wound care in civilian burns, ulcers and surgeries.

Optimised laser microdissection of the human ocular surface epithelial regions for microarray studies

PubMed Central

2013-01-01

Background The most important challenge of performing insitu transcriptional profiling of the human ocular surface epithelial regions is obtaining samples in sufficient amounts, without contamination from adjacent tissue, as the region of interest is microscopic and closely apposed to other tissues regions. We have effectively collected ocular surface (OS) epithelial tissue samples from the Limbal Epithelial Crypt (LEC), limbus, cornea and conjunctiva of post-mortem cadaver eyes with laser microdissection (LMD) technique for gene expression studies with spotted oligonucleotide microarrays and Gene 1.0 ST arrays. Methods Human donor eyes (4 pairs for spotted oligonucleotide microarrays, 3 pairs for Gene 1.0 ST arrays) consented for research were included in this study with due ethical approval of the Nottingham Research Ethics Committee. Eye retrieval was performed within 36 hours of post-mortem period. The dissected corneoscleral buttons were immersed in OCT media and frozen in liquid nitrogen and stored at −80°C till further use. Microscopic tissue sections of interest were taken on PALM slides and stained with Toluidine Blue for laser microdissection with PALM microbeam systems. Optimisation of the laser microdissection technique was crucial for efficient and cost effective sample collection. Results The starting concentration of RNA as stipulated by the protocol of microarray platforms was taken as the cut-off concentration of RNA samples in our studies. The area of LMD tissue processed for spotted oligonucleotide microarray study ranged from 86,253 μm2 in LEC to 392,887 μm2 in LEC stroma. The RNA concentration of the LMD samples ranged from 22 to 92 pg/μl. The recommended starting concentration of the RNA samples used for Gene 1.0 ST arrays was 6 ng/5 μl. To achieve the desired RNA concentration the area of ocular surface epithelial tissue sample processed for the Gene 1.0 ST array experiments was approximately 100,0000 μm2 to 130,0000 μm2. RNA concentration of these samples ranged from 10.88 ng/12 μl to 25.8 ng/12 μl, with the RNA integrity numbers (RIN) for these samples from 3.3 to 7.9. RNA samples with RIN values below 2, that had failed to amplify satisfactorily were discarded. Conclusions The optimised protocol for sample collection and laser microdissection improved the RNA yield of the insitu ocular surface epithelial regions for effective microarray studies on spotted oligonucleotide and affymetrix platforms. PMID:24160452

Inflammation in dry eye.

PubMed

Stern, Michael E; Pflugfelder, Stephen C

2004-04-01

Dry eye is a condition of altered tear composition that results from a diseased or dysfunctional lacrimal functional unit. Evidence suggests that inflammation causes structural alterations and/or functional paralysis of the tear-secreting glands. Changes in tear composition resulting from lacrimal dysfunction, increased evaporation and/or poor clearance have pro-inflammatory effects on the ocular surface. This inflammation is responsible in part for the irritation symptoms, ocular surface epithelial disease, and altered corneal epithelial barrier function in dry eye. Anti-inflammatory therapies for dry eye target one or more of the inflammatory mediators/pathways that have been identified in dry eye.

Surface Modifications of Dental Ceramic Implants with Different Glass Solder Matrices: In Vitro Analyses with Human Primary Osteoblasts and Epithelial Cells

PubMed Central

Mick, Enrico

2014-01-01

Ceramic materials show excellent esthetic behavior, along with an absence of hypersensitivity, making them a possible alternative implant material in dental surgery. However, their surface properties enable only limited osseointegration compared to titanium implants. Within this study, a novel surface coating technique for enhanced osseointegration was investigated biologically and mechanically. Specimens of tetragonal zirconia polycrystal (TZP) and aluminum toughened zirconia (ATZ) were modified with glass solder matrices in two configurations which mainly consisted of SiO2, Al2O3, K2O, and Na2O. The influence on human osteoblastic and epithelial cell viability was examined by means of a WST-1 assay as well as live/dead staining. A C1CP-ELISA was carried out to verify procollagen type I production. Uncoated/sandblasted ceramic specimens and sandblasted titanium surfaces were investigated as a reference. Furthermore, mechanical investigations of bilaterally coated pellets were conducted with respect to surface roughness and adhesive strength of the different coatings. These tests could demonstrate a mechanically stable implant coating with glass solder matrices. The coated ceramic specimens show enhanced osteoblastic and partly epithelial viability and matrix production compared to the titanium control. Hence, the new glass solder matrix coating could improve bone cell growth as a prerequisite for enhanced osseointegration of ceramic implants. PMID:25295270

Surface modifications of dental ceramic implants with different glass solder matrices: in vitro analyses with human primary osteoblasts and epithelial cells.

PubMed

Markhoff, Jana; Mick, Enrico; Mitrovic, Aurica; Pasold, Juliane; Wegner, Katharina; Bader, Rainer

2014-01-01

Ceramic materials show excellent esthetic behavior, along with an absence of hypersensitivity, making them a possible alternative implant material in dental surgery. However, their surface properties enable only limited osseointegration compared to titanium implants. Within this study, a novel surface coating technique for enhanced osseointegration was investigated biologically and mechanically. Specimens of tetragonal zirconia polycrystal (TZP) and aluminum toughened zirconia (ATZ) were modified with glass solder matrices in two configurations which mainly consisted of SiO2, Al2O3, K2O, and Na2O. The influence on human osteoblastic and epithelial cell viability was examined by means of a WST-1 assay as well as live/dead staining. A C1CP-ELISA was carried out to verify procollagen type I production. Uncoated/sandblasted ceramic specimens and sandblasted titanium surfaces were investigated as a reference. Furthermore, mechanical investigations of bilaterally coated pellets were conducted with respect to surface roughness and adhesive strength of the different coatings. These tests could demonstrate a mechanically stable implant coating with glass solder matrices. The coated ceramic specimens show enhanced osteoblastic and partly epithelial viability and matrix production compared to the titanium control. Hence, the new glass solder matrix coating could improve bone cell growth as a prerequisite for enhanced osseointegration of ceramic implants.

Epithelial rotation is preceded by planar symmetry breaking of actomyosin and protects epithelial tissue from cell deformations.

PubMed

Viktorinová, Ivana; Henry, Ian; Tomancak, Pavel

2017-11-01

Symmetry breaking is involved in many developmental processes that form bodies and organs. One of them is the epithelial rotation of developing tubular and acinar organs. However, how epithelial cells move, how they break symmetry to define their common direction, and what function rotational epithelial motions have remains elusive. Here, we identify a dynamic actomyosin network that breaks symmetry at the basal surface of the Drosophila follicle epithelium of acinar-like primitive organs, called egg chambers, and may represent a candidate force-generation mechanism that underlies the unidirectional motion of this epithelial tissue. We provide evidence that the atypical cadherin Fat2, a key planar cell polarity regulator in Drosophila oogenesis, directs and orchestrates transmission of the intracellular actomyosin asymmetry cue onto a tissue plane in order to break planar actomyosin symmetry, facilitate epithelial rotation in the opposite direction, and direct the elongation of follicle cells. In contrast, loss of this rotational motion results in anisotropic non-muscle Myosin II pulses that are disorganized in plane and causes cell deformations in the epithelial tissue of Drosophila eggs. Our work demonstrates that atypical cadherins play an important role in the control of symmetry breaking of cellular mechanics in order to facilitate tissue motion and model epithelial tissue. We propose that their functions may be evolutionarily conserved in tubular/acinar vertebrate organs.

Epithelial rotation is preceded by planar symmetry breaking of actomyosin and protects epithelial tissue from cell deformations

PubMed Central

Henry, Ian; Tomancak, Pavel

2017-01-01

Symmetry breaking is involved in many developmental processes that form bodies and organs. One of them is the epithelial rotation of developing tubular and acinar organs. However, how epithelial cells move, how they break symmetry to define their common direction, and what function rotational epithelial motions have remains elusive. Here, we identify a dynamic actomyosin network that breaks symmetry at the basal surface of the Drosophila follicle epithelium of acinar-like primitive organs, called egg chambers, and may represent a candidate force-generation mechanism that underlies the unidirectional motion of this epithelial tissue. We provide evidence that the atypical cadherin Fat2, a key planar cell polarity regulator in Drosophila oogenesis, directs and orchestrates transmission of the intracellular actomyosin asymmetry cue onto a tissue plane in order to break planar actomyosin symmetry, facilitate epithelial rotation in the opposite direction, and direct the elongation of follicle cells. In contrast, loss of this rotational motion results in anisotropic non-muscle Myosin II pulses that are disorganized in plane and causes cell deformations in the epithelial tissue of Drosophila eggs. Our work demonstrates that atypical cadherins play an important role in the control of symmetry breaking of cellular mechanics in order to facilitate tissue motion and model epithelial tissue. We propose that their functions may be evolutionarily conserved in tubular/acinar vertebrate organs. PMID:29176774

Analysis of Free Amino Acids in Different Extracts of Orthosiphon stamineus Leaves by High-Performance Liquid Chromatography Combined with Solid-Phase Extraction

PubMed Central

Shafaei, Armaghan; Halim, Nor Hidayah Ab; Zakaria, Norhidayah; Ismail, Zhari

2017-01-01

Background: Orthosiphon stamineus (OS) Benth is a medicinal plant and native in Southeast Asia. Previous studies have shown that OS leaves possess antioxidant, cytotoxic, diuretic, antihypertensive, and uricosuric effects. These beneficial effects have been attributed to the presence of primary and secondary metabolites such as polyphenols, amino acids, and flavonoids. Objective: To develop and validate an high-performance liquid chromatography (HPLC)-diode array detector (DAD) method combined with solid-phase extraction that involves precolumn derivatization with O-phthaladehyde for simultaneous analysis of free amino acids in OS leaves extracts. Materials and Methods: OS leaves were extracted with water (OS-W), ethanol (OS-E), methanol (OS-M), 50% ethanol (OS-EW), and 50% methanol (OS-MW). The extracts were treated by C18 cartridge before derivatization, resulting in great improvement of separation by Zorbox Eclipse XDB-C18 column. Results: The HPLC–DAD method was successfully developed and validated for analyzing the contents of free amino acids in OS extracts. The results showed that l-aspartic acid with 0.93 ± 0.01 nmol/mg was the major free amino acid in OS-W extract. However, in OS-E, OS-M, OS-EW, and OS-MW, l-glutamic acid with 3.53 ± 0.16, 2.17 ± 0.10, 4.01 ± 0.12, and 2.49 ± 0.12 nmol/mg, respectively, was the major free amino acid. Subsequently, l-serine, which was detected in OS-W, OS-E, and OS-M, was the minor free amino acid with 0.33 ± 0.02, 0.12 ± 0.01, and 0.06 ± 0.01 nmol/mg, respectively. However, l-threonine with 0.26 ± 0.02 and 0.19 ± 0.08 nmol/mL in OS-EW and OS-MW, respectively, had the lowest concentration compared with other amino acid components. Conclusion: All validation parameters of the developed method indicate that the method is reliable and efficient to simultaneously determine the free amino acids content for routine analysis of OS extracts. SUMMARY The HPLC-DAD method combined with solid phase extraction was successfully developed and validated for simultaneous determination and quantification of 17 free amino acids in Orthosiphon stamineus (OS) Benth extractsOS extracts were found to be rich in free amino acid contentL-aspartic acid was the major free amino acid in OS water extract while, in OS ethanol, methanol, 50% ethanol and 50% methanol extracts, L-glutamic acid was the major free amino acidL-serine was the minor free amino acid in OS water, ethanol and methanol extracts while, in OS 50% ethanol and 50% methanol extracts, L-threonine had the lowest concentration compared to other amino acid components. Abbreviations used: HPLC-DAD: High-Performance Liquid Chromatography with Diode-Array Detection, OS: Orthosiphon stamineus, OS-W: Orthosiphon stamineus water extract, OS-E: Orthosiphon stamineus ethanol extract, OS-M: Orthosiphon stamineus methanol extract, OS-EW: Orthosiphon stamineus 50% ethanol extract, OS-MW: Orthosiphon stamineus 50% methanol extract, OPA: O-phthaladehyde, SPE: Solid Phase Extraction, UV: Ultraviolet, LOD: Limit of Detection, LOQ: Limit of Quantification, RSD: Relative Standard Deviation. PMID:29142388

Assimilation of COST 716 Near-Real Time GPS data in the nonhydrostatic limited area model used at MeteoSwiss

NASA Astrophysics Data System (ADS)

Guerova, G.; Bettems, J.-M.; Brockmann, E.; Matzler, Ch.

2006-01-01

Application of the GPS derived water vapor into Numerical Weather Prediction (NWP) models is one of the focuses of the COST Action 716 “Exploitation of Ground based GPS for climate and numerical weather prediction applications”. For this purpose the GPS data covering Europe have been collected within the Near-Real Time (NRT) demonstration project and provided for Observing System Experiments (OSE). For the experiments presented in this manuscript the operational NWP system of MeteoSwiss is used. The limited area nonhydrostatic aLpine Model (aLMo) of MeteoSwiss covers most of western Europe, has a horizontal resolution of 7 km, 45 layers in the vertical, and uses a data assimilation scheme based on the Newtonian relaxation (nudging) method. In total 17 days analyses and two 30 hours daily forecasts have been computed, with 100 GPS sites assimilated for three selected periods in autumn 2001, winter and summer 2002. It is to be noted that only in the last period data from 10 french sites, i.e. west of Switzerland are assimilated. The GPS NRT data quality has been compared with the Post-Processed data. Agreement within 3 mm level Zenith Total Delay bias and 8 mm standard deviation was found, corresponding to an Integrated Water Vapor (IWV) bias below 0.5 kg/m2. Most of the NRT data over aLMo domain are available within a prescribed time window of 1 h 45 min. In the nudging process the NRT data are successfully used by the model to correct the IWV deficiencies present in the reference analysis; stronger forcing with a shorter time scale could be however recommended. Comparing the GPS derived IWV with radiosonde observations, a dry radiosonde bias has been found over northern Italy. Through GPS data assimilation the aLMo analysis bias and standard deviation in the diurnal cycle has been reduced. The negative bias of 0.64 kg/m2 in the reference analysis has been reduced to 0.34 kg/m2 in GPS analysis. However, the diurnal cycle statistic from the forecast does show the characteristic negative bias only slightly reduced starting with the GPS analysis. The GPS IWV impact on aLMo is large in June 2002 and moderate in September 2001 OSE. January OSE is inconclusive due to inconsistent use of humidity data below the freezing point. In June 2002 OSE, a substantial IWV impact is seen up to the end of the forecast. Over Switzerland the dry bias in the reference analysis has been successfully corrected and the 2 m temperature and dew point have been slightly improved over the whole aLMo domain. The subjective verification of precipitation against radar data in autumn 2001 and summer 2002 gives mixed results. In the forecast the impact is limited to the first six hours and to strong precipitation events. A missing precipitation pattern has been recovered via GPS assimilation in June 20 2002 forecast. A negative impact on precipitation analysis on June 23 has been observed. The future operational use of GPS will depend on data availability; European GPS networks belong mainly to the geodetic community. A further increase of GPS network density in southern Europe is welcome. The GPS derived gradient and Slant Path estimates could possibly improve efficiency of IWV assimilation via the nudging technique.

Transmigrated neutrophils in the intestinal lumen engage ICAM 1 to regulate the epithelial barrier and neutrophil recruitment

PubMed Central

Sumagin, Ronen; Robin, Alex Z.; Nusrat, Asma; Parkos, Charles A.

2014-01-01

Neutrophil (PMN) transepithelial migration (TEM) and accumulation in luminal spaces is a hallmark of mucosal inflammation. TEM has been extensively modeled, however the functional consequences and molecular basis of PMN interactions with luminal epithelial ligands are not clear. Here we report that cytokine-induced expression of a PMN ligand, intercellular adhesion molecule-1 (ICAM-1), exclusively on the luminal (apical) membrane of the intestinal epithelium results in accumulation and enhanced motility of transmigrated PMN on the apical epithelial surface. Using complementary in-vitro and in-vivo approaches we demonstrate that ligation of epithelial ICAM-1 by PMN or with specific antibodies results in myosin light chain kinase (MLCK)-dependent increases in epithelial permeability that are associated with enhanced PMN TEM. Effects of ICAM-1 ligation on epithelial permeability and PMN migration in-vivo were blocked after intraluminal addition of peptides derived from the cytoplasmic domain of ICAM-1. These findings provide new evidence for functional interactions between PMN and epithelial cells after migration into the intestinal lumen. While such interactions may aid in clearance of invading microorganisms by promoting PMN recruitment, engagement of ICAM-1 under pathologic conditions would increase accumulation of epithelial-associated PMN, thus contributing to mucosal injury as observed in conditions including ulcerative colitis. PMID:24345805

Subepithelial corneal fibrosis partially due to epithelial-mesenchymal transition of ocular surface epithelium

PubMed Central

Kawashima, Motoko; Higa, Kazunari; Satake, Yoshiyuki; Omoto, Masahiro; Tsubota, Kazuo; Shimmura, Shigeto; Shimazaki, Jun

2010-01-01

Purpose To determine whether epithelial-mesenchymal transition is involved in the development of corneal subepithelial fibrosis (pannus). Methods Frozen samples of pannus tissue removed from human corneas with a diagnosis of total limbal stem cell deficiency were characterized by immunostaining for both epithelial and mesenchymal markers. We selected transformation-related protein 63 (p63) and pancytokeratin as epithelial markers and vimentin and α-smooth muscle actin (α-SMA) as mesenchymal markers. Immunostaining for β-catenin and E-cadherin was performed to determine wingless-Int (Wnt)-pathway activation. RT–PCR analysis was also performed on epithelial tissue obtained from pannus samples after dispase digestion. Results Immunohistochemistry revealed strong nuclear expression of p63 and weak intercellular expression of E-cadherin in epithelial basal cells of pannus tissue. Furthermore, translocation of β-catenin from intercellular junctions to the nucleus and cytoplasm was also observed. Double-positive cells for both p63 and α-SMA were observed in the subepithelial stroma of pannus tissue, which was supported by RT–PCR and cytospin analysis. Conclusions Epithelial-mesenchymal transition may be partially involved in the development of subepithelial corneal fibrosis due to total limbal stem cell deficiency. PMID:21179238

Shigella gets captured to gain entry.

PubMed

McCormick, Beth A

2011-06-16

The type III secretion system-dependent epithelial invasion and dissemination of Shigella is stimulated by ATP released through hemichannels. Romero et al. (2011) show that prior to epithelial contact, Shigella is captured by nanometer-thin micropodial extensions at a distance from the cell surface, in a process involving ATP and connexin-mediated signaling. Copyright © 2011 Elsevier Inc. All rights reserved.

Expression and Mutational Analysis of c-kit in Ovarian Surface Epithelial Tumors

PubMed Central

Lee, Myung-Hoon; Park, Tae-In; Bae, Han-Ik

2006-01-01

Coexpression of Kit ligand and c-kit has been reported in some gynecologic tumors. To determine whether imatinib mesylate is useful in ovarian epithelial tumors, we performed immunohistochemical and mutational analysis. The cases consisted of 33 cases, which included 13 serous cystadenocarcinomas, 1 borderline serous tumor, 8 mucinous cystadenocarcinomas, 6 borderline mucinous tumors and 5 clear cell carcinomas. Five cases of serous cystadenoma and 5 cases of mucinous cystadenoma were also included. In the immunohistochemical study, 3 cases (3/6, 50%) of borderline mucinous cystic tumor and two cases (2/8, 25%) of mucinous cystadenocarcinoma show positive staining for KIT protein. Only one case (1/13, 7.7%) of serous cystadenocarcinoma had positive staining. On mutational analysis, no mutation was identified at exon 11. However, two cases of borderline mucinous tumors and one case of mucinous cystadenocarcinoma had mutations at exon 17. In these cases, the immunohistochemistry also shows focal positive staining at epithelial component. Although, KIT protein expression showed higher incidence in mucinous tumors than serous tumors, they lack KIT-activating mutations in exon 11. Thus, ovarian surface epithelial tumors are unlikely to respond to imatinib mesylate. PMID:16479070

Glutathione aerosol suppresses lung epithelial surface inflammatory cell-derived oxidants in cystic fibrosis.

PubMed

Roum, J H; Borok, Z; McElvaney, N G; Grimes, G J; Bokser, A D; Buhl, R; Crystal, R G

1999-07-01

Cystic fibrosis (CF) is characterized by accumulation of activated neutrophils and macrophages on the respiratory epithelial surface (RES); these cells release toxic oxidants, which contribute to the marked epithelial derangements seen in CF. These deleterious consequences are magnified, since reduced glutathione (GSH), an antioxidant present in high concentrations in normal respiratory epithelial lining fluid (ELF), is deficient in CF ELF. To evaluate the feasibility of increasing ELF GSH levels and enhancing RES antioxidant protection, GSH aerosol was delivered (600 mg twice daily for 3 days) to seven patients with CF. ELF total, reduced, and oxidized GSH increased (P < 0.05, all compared with before GSH therapy), suggesting adequate RES delivery and utilization of GSH. Phorbol 12-myristate 13-acetate-stimulated superoxide anion (O2-.) release by ELF inflammatory cells decreased after GSH therapy (P < 0.002). This paralleled observations that GSH added in vitro to CF ELF inflammatory cells suppressed O2-. release (P < 0.001). No adverse effects were noted during treatment. Together, these observations demonstrate the feasibility of using GSH aerosol to restore RES oxidant-antioxidant balance in CF and support the rationale for further clinical evaluation.

Ion Transport by Pulmonary Epithelia

PubMed Central

Hollenhorst, Monika I.; Richter, Katrin; Fronius, Martin

2011-01-01

The lung surface of air-breathing vertebrates is formed by a continuous epithelium that is covered by a fluid layer. In the airways, this epithelium is largely pseudostratified consisting of diverse cell types such as ciliated cells, goblet cells, and undifferentiated basal cells, whereas the alveolar epithelium consists of alveolar type I and alveolar type II cells. Regulation and maintenance of the volume and viscosity of the fluid layer covering the epithelium is one of the most important functions of the epithelial barrier that forms the outer surface area of the lungs. Therefore, the epithelial cells are equipped with a wide variety of ion transport proteins, among which Na+, Cl−, and K+ channels have been identified to play a role in the regulation of the fluid layer. Malfunctions of pulmonary epithelial ion transport processes and, thus, impairment of the liquid balance in our lungs is associated with severe diseases, such as cystic fibrosis and pulmonary oedema. Due to the important role of pulmonary epithelial ion transport processes for proper lung function, the present paper summarizes the recent findings about composition, function, and ion transport properties of the airway epithelium as well as of the alveolar epithelium. PMID:22131798

Transepithelial transport and toxicity of PAMAM dendrimers: implications for oral drug delivery.

PubMed

Sadekar, S; Ghandehari, H

2012-05-01

This article summarizes efforts to evaluate poly(amido amine) (PAMAM) dendrimers as carriers for oral drug delivery. Specifically, the effect of PAMAM generation, surface charge and surface modification on toxicity, cellular uptake and transepithelial transport is discussed. Studies on Caco-2 monolayers, as models of intestinal epithelial barrier, show that by engineering surface chemistry of PAMAM dendrimers, it is possible to minimize toxicity while maximizing transepithelial transport. It has been demonstrated that PAMAM dendrimers are transported by a combination of paracellular and transcellular routes. Depending on surface chemistry, PAMAM dendrimers can open the tight junctions of epithelial barriers. This tight junction opening is in part mediated by internalization of the dendrimers. Transcellular transport of PAMAM dendrimers is mediated by a variety of endocytic mechanisms. Attachment or complexation of cytotoxic agents to PAMAM dendrimers enhances the transport of such drugs across epithelial barriers. A remaining challenge is the design and development of linker chemistries that are stable in the gastrointestinal tract (GIT) and the blood stream, but amenable to cleavage at the target site of action. Recent efforts have focused on the use of PAMAM dendrimers as penetration enhancers. Detailed in vivo oral bioavailability of PAMAM dendrimer-drug conjugates, as a function of physicochemical properties will further need to be assessed. Copyright © 2011 Elsevier B.V. All rights reserved.

TRANSEPITHELIAL TRANSPORT AND TOXICITY OF PAMAM DENDRIMERS: IMPLICATIONS FOR ORAL DRUG DELIVERY

PubMed Central

Sadekar, S.; Ghandehari, H.

2011-01-01

This article summarizes efforts to evaluate poly(amido amine) (PAMAM) dendrimers as carriers for oral drug delivery. Specifically, the effect of PAMAM generation, surface charge and surface modification on toxicity, cellular uptake and transepithelial transport is discussed. Studies on Caco-2 monolayers, as models of intestinal epithelial barrier, show that by engineering surface chemistry of PAMAM dendrimers, it is possible to minimize toxicity while maximizing transepithelial transport. It has been demonstrated that PAMAM dendrimers are transported by a combination of paracellular and transcellular routes. Depending on surface chemistry, PAMAM dendrimers can open the tight junctions of epithelial barriers. This tight junction opening is in part mediated by internalization of the dendrimers. Transcellular transport of PAMAM dendrimers is mediated by a variety of endocytic mechanisms. Attachment or complexation of cytotoxic agents to PAMAM dendrimers enhances the transport of such drugs across epithelial barriers. A remaining challenge is the design and development of linker chemistries that are stable in the gastrointestinal tract (GIT) and the blood stream, but amenable to cleavage at the target site of action. Recent efforts have focused on the use of PAMAM dendrimers as penetration enhancers. Detailed in vivo oral bioavailability of PAMAM dendrimer – drug conjugates, as a function of physicochemical properties will further need to be assessed. PMID:21983078

Expression of Pneumocystis jirovecii Major Surface Glycoprotein in Saccharomyces cerevisiae

PubMed Central

Kutty, Geetha; England, Katherine J.; Kovacs, Joseph A.

2013-01-01

The major surface glycoprotein (Msg), which is the most abundant protein expressed on the cell surface of Pneumocystis organisms, plays an important role in the attachment of this organism to epithelial cells and macrophages. In the present study, we expressed Pneumocystis jirovecii Msg in Saccharomyces cerevisiae, a phylogenetically related organism. Full-length P. jirovecii Msg was expressed with a DNA construct that used codons optimized for expression in yeast. Unlike in Pneumocystis organisms, recombinant Msg localized to the plasma membrane of yeast rather than to the cell wall. Msg expression was targeted to the yeast cell wall by replacing its signal peptide, serine-threonine–rich region, and glycophosphatidylinositol anchor signal region with the signal peptide of cell wall protein α-agglutinin of S. cerevisiae, the serine-threonine–rich region of epithelial adhesin (Epa1) of Candida glabrata, and the carboxyl region of the cell wall protein (Cwp2) of S. cerevisiae, respectively. Immunofluorescence analysis and treatment with β-1,3 glucanase demonstrated that the expressed Msg fusion protein localized to the yeast cell wall. Surface expression of Msg protein resulted in increased adherence of yeast to A549 alveolar epithelial cells. Heterologous expression of Msg in yeast will facilitate studies of the biologic properties of Pneumocystis Msg. PMID:23532098

Defense Information Systems Agency Technical Integration Support (DISA- TIS). MUMPS Study.

DTIC Science & Technology

1993-01-01

usable in DoD, MUMPS must continue to improve in its support of DoD and OSE standards such as SQL , X-Windows, POSIX, PHIGS, etc. MUMPS and large AlSs...Language ( SQL ), X-Windows, and Graphical Kernel Services (GKS)) 2.2.2.3 FIPS Adoption by NIST The National Institute of Standards and Technology (NIST...many of the performance tuning mechanisms that must be performed explicitly with other systems. The VA looks forward to the SQL binding (1993 ANS) that

Airport Activity Statistics of Certificated Route Air Carriers.

DTIC Science & Technology

1980-12-31

Calif.-------llmdale/Laneaster Clarkston, Wash.-------kwiston/Clarkston Lan4d (ViLnks, Win- -lth~inelander/Lund O’hLaIes (Under Idaho ) Lander. Wyo...Durham. N. C.-------laleigh/Durhan, Moscow. Idaho --------llman/Moseow D~usseldorf, Germany.,- Cologne/ imiseldorl/Bonn (Under Washington) M1oses Lake...MPIUNNITY TOTok q DINSTI ( . $S HEOULOU 888916 692.97 232.31 181.29 413.60 1106.57 92 q+s IDAHO 91 96 :- IS $ 0.18 ou 480351F AIR 1F881lN8L16158EN

Less Expensive Internal Management Options May be Viable Alternatives for Countering Critical Military Skill Shortages.

DTIC Science & Technology

1982-04-19

funded authorized spaces for an occupation at .a specified skill level and the number of personnel in the inventory who, for assignment pur- poses, meet t...ose requirements. Because the Air Force’s end of fiscal year personnel inventory usually is at or very close to its congressionally authorized end...used projected end of fiscal year 1982 authoriza- tions and the actual personnel inventory as of September 30, 1981. Using these criteria the study

Proceedings of the Annual Chemical Defense Bioscience Review (5th) Held at Columbia, Maryland on 29-31 May 1985. Appendix 3

DTIC Science & Technology

1985-06-01

WHICH CAN READILY BE UTILIZED IN PREDICTIVE PHARMACOKINETIC MODELS. B A N I SOLATrED, PERFUSECD V IAELE SKIN PREPARATION WOULD OVERCOME MANY OF THESE...PASS" CUTANEOUS BIOTRANSFORMATION; 2. ASSESSING THE EFFECTS OF C11ANGING BLOOD FLOW OR ALTERED EPIDERMAL METABOLISM ON PERCUTANEOUS ABSORPTION...COMPLETELY. THE PERFUSION APPARATUS IS A Cl,.OSED, RECIRCULATING SYSTEM OPTIMIZED FOR THE RELATIVELY LOW PERFUSATE FLOW RATES OF 0.5 TO 2. 5 ML/MIN/FLAP

Stimulating Rhetorical Invention in English Composition through Computer-Assisted Instruction.

DTIC Science & Technology

1979-08-01

action, and the father a cause of the child , and in general the agent the cause of the deed." "Final" cause, "the end, i.e. that for the sake of which a...YOU CTANY YOU SMULO’WT 11lls P414T ’of AwAI OP CAUSTERPRETO SELL.SIS. B 5C.ODC 11414 POrN ? ’IUA4De OSE~ rI WRINGS I O ON ASI 11ls. POINT ’WILL EAO Y

Defense AT and L. Volume 28, Number 3, 2009

DTIC Science & Technology

2009-01-01

system to help create a defensible demand signal for people which can be funded and executed. This is fundamental to the successful execution of defense...The acq uisition wo rkforce is a ging and l osing talen t, and now is the time t o put plan s in place to keep th e workforc e operatin g at peak...workforce is critical for improving acquisition outcomes for the nation’s $1.6 trillion investment in acquisition systems and services. The new

News of Higher Educational Institutions, Ministry of Higher Education USSR, Radiophysics Series

DTIC Science & Technology

1960-12-30

formulate the following proposition: • • 2. " Theorem 2. If the elements AyA ^i (i^t j) of the ; determinant D ,, T*ose diagonal elements...34 OFFICE OF TECHNICAL SERVICES Ü. S. DEPARTMENT OF COMMERCE WASHINGTON 1% D * Ce U. S.’ JOINT PUBLICATIONS RESEARCH SERVICE 1636 CONNECTICUT AVE...N.W. WASHINGTON Z% D , C. FOREWORD "il ELIS publication vas ’.prepared under ■ contract "by the \\JKITED SPATES , JOIET’PUBLICATIONS RE- SEARCH

In Vitro Response of Guinea Pig Peritoneal Macrophages to Legionella pneumophila

DTIC Science & Technology

1981-03-01

In Vitro Responlse of Guinea Pig Peritoneal Macrophages to Legionella pneumophila It. A. KISIIIMi~O~’ .1. Ii.,W11ITE, F. G. SIREY, V. (U.1 Mc(GANN, R...Tlhe inter- act ion between L. lincumnophila andl( peritoneal macrophages front normial guinea pigs or front animials that had survived infection was...roagglujtiniat titer) guinea pig serum to The purp~ose of this study "as to investigate contain approximately 108 organisms per ml. the phagocytic and

HIV internalization into oral and genital epithelial cells by endocytosis and macropinocytosis leads to viral sequestration in the vesicles

PubMed Central

Yasen, Aizezi; Herrera, Rossana; Rosbe, Kristina; Lien, Kathy; Tugizov, Sharof M.

2018-01-01

Recently, we showed that HIV-1 is sequestered, i.e., trapped, in the intracellular vesicles of oral and genital epithelial cells. Here, we investigated the mechanisms of HIV-1 sequestration in vesicles of polarized tonsil, foreskin and cervical epithelial cells. HIV-1 internalization into epithelial cells is initiated by multiple entry pathways, including clathrin-, caveolin/lipid raft-associated endocytosis and macropinocytosis. Inhibition of HIV-1 attachment to galactosylceramide and heparan sulfate proteoglycans, and virus endocytosis and macropinocytosis reduced HIV-1 sequestration by 30–40%. T-cell immunoglobulin and mucin domain 1 (TIM-1) were expressed on the apical surface of polarized tonsil, cervical and foreskin epithelial cells. However, TIM-1-associated HIV-1 macropinocytosis and sequestration were detected mostly in tonsil epithelial cells. Sequestered HIV-1 was resistant to trypsin, pronase, and soluble CD4, indicating that the sequestered virus was intracellular. Inhibition of HIV-1 intraepithelial sequestration and elimination of vesicles containing virus in the mucosal epithelium may help in the prevention of HIV-1 mucosal transmission. PMID:29277006

EphA2 is an epithelial cell pattern recognition receptor for fungal β-glucans

PubMed Central

Swidergall, Marc; Solis, Norma V.; Lionakis, Michail S.; Filler, Scott G.

2017-01-01

Oral epithelial cells discriminate between pathogenic and non-pathogenic stimuli, and only induce an inflammatory response when they are exposed to high levels of a potentially harmful microorganism. The pattern recognition receptors (PRRs) in epithelial cells that mediate this differential response are poorly understood. Here, we demonstrate that the ephrin type-A receptor 2 (EphA2) is an oral epithelial cell PRR that binds to exposed β-glucans on the surface of the fungal pathogen Candida albicans. Binding of C. albicans to EphA2 on oral epithelial cells activates signal transducer and activator of transcription 3 (Stat3) and mitogen-activated protein kinase signaling in an inoculum-dependent manner, and is required for induction of a pro-inflammatory and antifungal response. EphA2−/− mice have impaired inflammatory responses and reduced IL-17 signaling during oropharyngeal candidiasis, resulting in more severe disease. Our study reveals that EphA2 functions as PRR for β-glucans that senses epithelial cell fungal burden and is required for the maximal mucosal inflammatory response to C. albicans. PMID:29133884

Airway epithelial repair in health and disease: Orchestrator or simply a player?

PubMed

Iosifidis, Thomas; Garratt, Luke W; Coombe, Deirdre R; Knight, Darryl A; Stick, Stephen M; Kicic, Anthony

2016-04-01

Epithelial cells represent the most important surface of contact in the body and form the first line of defence of the body to external environment. Consequently, epithelia have numerous roles in order to maintain a homeostatic defence barrier. Although the epithelium has been extensively studied over several decades, it remains the focus of new research, indicating a lack of understanding that continues to exist around these cells in specific disease settings. Importantly, evidence is emerging that airway epithelial cells in particular have varied complex functions rather than simple passive roles. One area of current interest is its role following injury. In particular, the epithelial-specific cellular mechanisms regulating their migration during wound repair remain poorly understood and remain an area that requires much needed investigation. A better understanding of the physiological, cellular and molecular wound repair mechanisms could assist in elucidating pathological processes that contribute to airway epithelial pathology. This review attempts to highlight migration-specific and cell-extracellular matrix (ECM) aspects of repair used by epithelial cells under normal and disease settings, in the context of human airways. © 2016 Asian Pacific Society of Respirology.

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

[Cultivated keratinocytes on micro-carriers: in vitro studies of a new carrier system].

PubMed

Hecht, J; Hoefter, E A; Hecht, J; Haraida, S; Nerlich, A; Hartinger, A; Mühlbauer, W; Dimoudis, N

1997-03-01

Epidermal grafts from confluently cultivated keratinocytes have been used since the early eighties for the treatment of severe burns, where the shortage of donor sites for split-thickness skin grafts did not allow for adequate wound coverage. The difficult handling of these grafts as well as the advanced differentiation of their epithelial cells into a multilayer sheet poses a problem for their clinical application. The aim of the study was to characterize cultivated keratinocytes, as well as to observe their migration and proliferation from the MC onto a surface. Keratinocytes were isolated from human foreskin and cultivated in serum-free and serum-containing medium according to a modified method by Rheinwald and Green. Collagen-coated Dextran beads were used as MC. The MC were colonized with keratinocytes using the Spinner culture technique. After seeding the colonized MC into culture flasks, their migration and proliferation was monitored regularly through immunohistochemical studies and measurement of the metabolic cell activity. Immunohistological staining proved that the cells isolated from human foreskin represent keratinocytes of the basal type. Keratinocytes, cultivated with serum-containing and serum free medium, both adhered to the surface of the MC, then migrated onto the surface of the flasks and proliferated to form a multilayer of epithelial cells. In the long-term, a flexible epithelial graft consisting of poorly differentiated keratinocytes should be available, which is simple to produce and easy to handle. This would be an alternative method for treating wounds, where the conventional multilayer epithelial graft (ET) is insufficient.

Establishment of a long-term three-dimensional primary culture of mouse glandular stomach epithelial cells within the stem cell niche

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katano, Takahito; Ootani, Akifumi; Department of Internal Medicine, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501

2013-03-22

Highlights: ► We established a 3D culture system to allow long-term culture of stomach cells. ► In this culture system, gastric epithelial cells grew for about 3 months. ► The cultured cells differentiated into multi-units of the stomach. ► This culture method should be useful for elucidating the cause of gastric diseases. -- Abstract: Compared to the small intestine and colon, little is known about stem cells in the stomach because of a lack of specific stem cell markers and an in vitro system that allows long-term culture. Here we describe a long-term three-dimensional (3D) primary gastric culture system withinmore » the stem cell niche. Glandular stomach cells from neonatal mice cultured in collagen gel yielded expanding sphere-like structures for 3 months. The wall of the gastrospheres consisted of a highly polarized epithelial monolayer with an outer lining of myofibroblasts. The epithelial cells showed a tall columnar cell shape, basal round nuclei, and mucus-filled cytoplasm as well as expression of MUC5AC, indicating differentiation into gastric surface mucous cells. These cells demonstrated the features of fully differentiated gastric surface mucous cells such as microvilli, junctional complexes, and glycogen and secretory granules. Fewer than 1% of cultured epithelial cells differentiated into enteroendocrine cells. Active proliferation of the epithelial cells and many apoptotic cells in the inner lumen revealed the rapid cell turnover in gastrospheres in vitro. This method enables us to investigate the role of signaling between cell–cell and epithelial–mesenchymal interactions in an environment that is extremely similar to the in vivo environment.« less

Femtosecond laser cutting of endothelial grafts: comparison of endothelial and epithelial applanation.

PubMed

Bernard, Aurélien; He, Zhiguo; Gauthier, Anne Sophie; Trone, Marie Caroline; Baubeau, Emmanuel; Forest, Fabien; Dumollard, Jean Marc; Peocʼh, Michel; Thuret, Gilles; Gain, Philippe

2015-02-01

Stromal surface quality of endothelial lamellae cut for endothelial keratoplasty with a femtosecond laser (FSL) with epithelial applanation remains disappointing. Applanation of the endothelial side of the cornea, mounted inverted on an artificial chamber, has therefore been proposed to improve cut quality. We compared lamellar quality after FSL cutting using epithelial versus endothelial applanation. Lamellae were cut with an FSL from organ-cultured corneas. After randomization, 7 were cut with epithelial applanation and 7 with endothelial applanation. Lamellae of 50-, 75-, and 100-μm thickness were targeted. Thickness was measured by optical coherence tomography before and immediately after cutting. Viable endothelial cell density was quantified immediately after cutting using triple labeling with Hoechst/ethidium/calcein-AM coupled with image analysis with ImageJ. The stromal surface was evaluated by 9 masked observers using semiquantitative scoring of scanning electronic microscopy images. Histology of 2 samples was also analyzed before lamellar detachment. Precision (difference in target/actual thickness) and thickness regularity [coefficient of variation (CV) of 10 measurements] were significantly better with endothelial applanation (precision: 18 μm; range, 10-30; CV: 11%; range, 8-12) than with epithelial applanation (precision: 84 μm; range, 54-107; P = 0.002; CV: 24%; range, 13-47; P = 0.001). Endothelial applanation provided thinner lamellae. However, viable endothelial cell density was significantly lower after endothelial applanation (1183 cells/mm2; range, 787-1725 versus 1688 cells/mm2; range, 1288-2025; P = 0.018). FSL cutting of endothelial lamellae using endothelial applanation provides thinner more regular grafts with more predictable thickness than with conventional epithelial applanation but strongly reduces the pool of viable endothelial cells.

Matrix metalloproteinase 9-induced increase in intestinal epithelial tight junction permeability contributes to the severity of experimental DSS colitis

PubMed Central

Nighot, Prashant; Al-Sadi, Rana; Guo, Shuhong; Watterson, D. Martin; Ma, Thomas

2015-01-01

Recent studies have implicated a pathogenic role for matrix metalloproteinases 9 (MMP-9) in inflammatory bowel disease. Although loss of epithelial barrier function has been shown to be a key pathogenic factor for the development of intestinal inflammation, the role of MMP-9 in intestinal barrier function remains unclear. The aim of this study was to investigate the role of MMP-9 in intestinal barrier function and intestinal inflammation. Wild-type (WT) and MMP-9−/− mice were subjected to experimental dextran sodium sulfate (DSS) colitis by administration of 3% DSS in drinking water for 7 days. The mouse colonic permeability was measured in vivo by recycling perfusion of the entire colon using fluorescently labeled dextran. The DSS-induced increase in the colonic permeability was accompanied by an increase in intestinal epithelial cell MMP-9 expression in WT mice. The DSS-induced increase in intestinal permeability and the severity of DSS colitis was found to be attenuated in MMP-9−/− mice. The colonic protein expression of myosin light chain kinase (MLCK) and phospho-MLC was found to be significantly increased after DSS administration in WT mice but not in MMP-9−/− mice. The DSS-induced increase in colonic permeability and colonic inflammation was attenuated in MLCK−/− mice and MLCK inhibitor ML-7-treated WT mice. The DSS-induced increase in colonic surface epithelial cell MLCK mRNA was abolished in MMP-9−/− mice. Lastly, increased MMP-9 protein expression was detected within the colonic surface epithelial cells in ulcerative colitis cases. These data suggest a role of MMP-9 in modulation of colonic epithelial permeability and inflammation via MLCK. PMID:26514773

CD147 Promotes Entry of Pentamer-Expressing Human Cytomegalovirus into Epithelial and Endothelial Cells

PubMed Central

Pritchard, Sarah R.; Wisner, Todd W.; Liu, Jing; Jardetzky, Ted S.; Johnson, David C.

2018-01-01

ABSTRACT Human cytomegalovirus (HCMV) replicates in many diverse cell types in vivo, and entry into different cells involves distinct entry mechanisms and different envelope glycoproteins. HCMV glycoprotein gB is thought to act as the virus fusogen, apparently after being triggered by different gH/gL proteins that bind distinct cellular receptors or entry mediators. A trimer of gH/gL/gO is required for entry into all cell types, and entry into fibroblasts involves trimer binding to platelet-derived growth factor receptor alpha (PDGFRα). HCMV entry into biologically relevant epithelial and endothelial cells and monocyte-macrophages also requires a pentamer, gH/gL complexed with UL128, UL130, and UL131, and there is evidence that the pentamer binds unidentified receptors. We screened an epithelial cell cDNA library and identified the cell surface protein CD147, which increased entry of pentamer-expressing HCMV into HeLa cells but not entry of HCMV that lacked the pentamer. A panel of CD147-specific monoclonal antibodies inhibited HCMV entry into epithelial and endothelial cells, but not entry into fibroblasts. shRNA silencing of CD147 in endothelial cells inhibited HCMV entry but not entry into fibroblasts. CD147 colocalized with HCMV particles on cell surfaces and in endosomes. CD147 also promoted cell-cell fusion induced by expression of pentamer and gB in epithelial cells. However, soluble CD147 did not block HCMV entry and trimer and pentamer did not bind directly to CD147, supporting the hypothesis that CD147 acts indirectly through other proteins. CD147 represents the first HCMV entry mediator that specifically functions to promote entry of pentamer-expressing HCMV into epithelial and endothelial cells. PMID:29739904

The role of extracellular matrix metalloproteinase inducer (EMMPRIN) in the regulation of bovine endometrial cell functions.

PubMed

Mishra, Birendra; Kizaki, Keiichiro; Sato, Takashi; Ito, Akira; Hashizume, Kazuyoshi

2012-06-01

Extracellular matrix metalloproteinase inducer (EMMPRIN) is a cell surface glycoprotein that stimulates the production of several matrix metalloproteinases (MMPs) for tissue remodeling. Previously, we detected EMMPRIN in the bovine endometrium, and it is mainly expressed in the luminal and glandular epithelium whereas MMPs are expressed in the underlying stroma. From this expression pattern, we hypothesized that EMMPRIN may regulate stromal MMPs in endometrial cell functions. To test this hypothesis, a coculture of epithelial and stromal cells was performed using a transwell system. In the coculture, epithelial cells were cultured on the insert membrane and stromal cell on the surface of well plates. Expression of stromal MMP-2 and MMP-14 was significantly higher in coculture with epithelial cell. Further, with the addition of anti-EMMPRIN antibody into the epithelial cell compartment, the expression of stromal EMMPRIN and MMP-2 and MMP-14 was decreased. To identify the active site of EMMPRIN for the augmentation of MMPs, EMMPRIN synthetic peptides that correspond to the extracellular loop domain-I (EM1, EM2, EM3, and EM4) were added into the epithelial cell compartment, and only EM2 at a higher dose interfered with EMMPRIN-mediated expression of MMP-14. Next, we examined the effects of progesterone and/or estrogen on the expression of EMMPRIN, MMP-2, and MMP-14. Progesterone (300 nM) significantly stimulated the expression of EMMPRIN but had no effects on any of the MMPs. These results suggest that EMMPRIN derived from epithelial cells regulates MMPs in the endometrium under progesterone-rich conditions and may thereby modulate bovine endometrial cell functions during gestation.

Mucin (MUC1) Expression and Function in Prostate Cancer Cells

DTIC Science & Technology

2001-09-01

Interactions at the Cell Surface of Mouse Uterine Epithelial Cells and Periimplantation -Stage Embryos. Trophoblast Res., 4:211-241, 1990. 37. Dutt...and Julian, J. Heparan Sulfate Proteoglycan Expression by Periimplantation Stage Embryos. Dev. Biol. 155:97-106,1993. 56. Rohde, L.H., and Carson...Modulators of Embryo-Uterine Epithelial Cell Attachment. In: S.K. Dey (ed.), Molecular and Cellular Aspects of Periimplantation Processes, Springer

Development of Raman Spectroscopy as a Clinical Diagnostic Tool

NASA Astrophysics Data System (ADS)

Borel, Santa

Raman spectroscopy is the collection of inelastically scattered light in which the spectra contain biochemical information of the probed cells or tissue. This work presents both targeted and untargeted ways that the technique can be exploited in biological samples. First, surface enhanced Raman scattering (SERS) gold nanoparticles conjugated to targeting antibodies were shown to be successful for multiplexed detection of overexpressed surface antigens in lung cancer cell lines. Further work will need to optimize the conjugation technique to preserve the strong binding affinity of the antibodies. Second, untargeted Raman microspectroscopy combined with multivariate statistical analysis was able to successfully differentiate mouse ovarian surface epithelial (MOSE) cells and spontaneously transformed ovarian surface epithelial (STOSE) cells with high accuracy. The differences between the two groups were associated with increased nucleic acid content in the STOSE cells. This shows potential for single cell detection of ovarian cancer.

Emergence of fractal geometry on the surface of human cervical epithelial cells during progression towards cancer

NASA Astrophysics Data System (ADS)

Dokukin, M. E.; Guz, N. V.; Woodworth, C. D.; Sokolov, I.

2015-03-01

Despite considerable advances in understanding the molecular nature of cancer, many biophysical aspects of malignant development are still unclear. Here we study physical alterations of the surface of human cervical epithelial cells during stepwise in vitro development of cancer (from normal to immortal (premalignant), to malignant). We use atomic force microscopy to demonstrate that development of cancer is associated with emergence of simple fractal geometry on the cell surface. Contrary to the previously expected correlation between cancer and fractals, we find that fractal geometry occurs only at a limited period of development when immortal cells become cancerous; further cancer progression demonstrates deviation from fractal. Because of the connection between fractal behaviour and chaos (or far from equilibrium behaviour), these results suggest that chaotic behaviour coincides with the cancer transformation of the immortalization stage of cancer development, whereas further cancer progression recovers determinism of processes responsible for cell surface formation.

Emerging of fractal geometry on surface of human cervical epithelial cells during progression towards cancer

PubMed Central

Dokukin, M. E.; Guz, N. V.; Woodworth, C.D.; Sokolov, I.

2015-01-01

Despite considerable advances in understanding the molecular nature of cancer, many biophysical aspects of malignant development are still unclear. Here we study physical alterations of the surface of human cervical epithelial cells during stepwise in vitro development of cancer (from normal to immortal (premalignant), to malignant). We use atomic force microscopy to demonstrate that development of cancer is associated with emergence of simple fractal geometry on the cell surface. Contrary to the previously expected correlation between cancer and fractals, we find that fractal geometry occurs only at a limited period of development when immortal cells become cancerous; further cancer progression demonstrates deviation from fractal. Because of the connection between fractal behaviour and chaos (or far from equilibrium behaviour), these results suggest that chaotic behaviour coincides with the cancer transformation of the immortalization stage of cancer development, whereas further cancer progression recovers determinism of processes responsible for cell surface formation. PMID:25844044

Solo and keratin filaments regulate epithelial tubule morphology.

PubMed

Nishimura, Ryosuke; Kato, Kagayaki; Fujiwara, Sachiko; Ohashi, Kazumasa; Mizuno, Kensaku

2018-04-28

Epithelial tubules, consisting of the epithelial cell sheet with a central lumen, are the basic structure of many organs. Mechanical forces play an important role in epithelial tubulogenesis; however, little is known about the mechanisms controlling the mechanical forces during epithelial tubule morphogenesis. Solo (also known as ARHGEF40) is a RhoA-targeting guanine-nucleotide exchange factor that is involved in mechanical force-induced RhoA activation and stress fiber formation. Solo binds to keratin-8/keratin-18 (K8/K18) filaments, and this interaction plays a crucial role in mechanotransduction. In this study, we examined the roles of Solo and K8/K18 filaments in epithelial tubulogenesis using MDCK cells cultured in 3D collagen gels. Knockdown of either Solo or K18 resulted in rounder tubules with increased lumen size, indicating that Solo and K8/K18 filaments play critical roles in forming the elongated morphology of epithelial tubules. Moreover, knockdown of Solo or K18 decreased the level of diphosphorylated myosin light chain (a marker of contractile force) at the luminal and outer surfaces of tubules, suggesting that Solo and K8/K18 filaments are involved in the generation of the myosin II-mediated contractile force during epithelial tubule morphogenesis. In addition, K18 filaments were normally oriented along the long axis of the tubule, but knockdown of Solo perturbed their orientation. These results suggest that Solo plays crucial roles in forming the elongated morphology of epithelial tubules and in regulating myosin II activity and K18 filament organization during epithelial tubule formation.

Urokinase and the intestinal mucosa: evidence for a role in epithelial cell turnover

PubMed Central

Gibson, P; Birchall, I; Rosella, O; Albert, V; Finch, C; Barkla, D; Young, G

1998-01-01

Background—The functions of urokinase in intestinal epithelia are unknown. 
Aims—To determine the relation of urokinase expressed by intestinal epithelial cells to their position in the crypt-villus/surface axis and of mucosal urokinase activity to epithelial proliferative kinetics in the distal colon. 
Methods—Urokinase expression was examined immunohistochemically in human intestinal mucosa. Urokinase activity was measured colorimetrically in epithelial cells isolated sequentially from the crypt-villus axis of the rat small intestine. In separate experiments, urokinase activity and epithelial kinetics (measured stathmokinetically) were measured in homogenates of distal colonic mucosa of 14 groups of eight rats fed diets known to alter epithelial turnover. 
Results—From the crypt base, an ascending gradient of expression and activity of urokinase was associated with the epithelial cells. Median mucosal urokinase activities in each of the dietary groups of rats correlated positively with autologous median number of metaphase arrests per crypt (r=0.68; p<0.005) and per 100 crypt cells (r=0.75; p<0.001), but not with crypt column height. 
Conclusions—Localisation of an enzyme capable of leading to digestion of cell substratum in the region where cells are loosely attached to their basement membrane, and the association of its activity with indexes of cell turnover, suggest a role for urokinase in facilitating epithelial cell loss in the intestine. 

 Keywords: urokinase; intestinal epithelium; colon; epithelial proliferation PMID:9824347

MUC1, the renaissance molecule.

PubMed

Gendler, S J

2001-07-01

MUC1 is a large, heavily glycosylated mucin expressed on the apical surfaces of most simple, secretory epithelia including the mammary gland, gastrointestinal, respiratory, urinary and reproductive tracts. Although MUC1 was thought to be an epithelial-specific protein, it is now known to be expressed on a variety of hematopoietic cells as well. Mucins function in protection and lubrication of epithelial surfaces. Transmembrane mucins, which contain cytoplasmic tail domains, appear to have additional functions through their abilities to interact with many proteins involved in signal transduction and cell adhesion. The goal of this review is to highlight recent discoveries that suggest that MUC1 may be a multifunctional protein, located on the surfaces of cells as a sensor of the environment, poised to signal to the interior when things go awry.

Mucin Production Dynamics at the Surface of Corneal Epithelial Cells

NASA Astrophysics Data System (ADS)

Hormel, Tristan; Bhattacharjee, Tapomoy; Pitenis, Angela; Urueã+/-A, Juan; Sawyer, Gregory; Angelini, Thomas

Mucous layers form at the apical surface of many epithelia, protecting tissues from pathogens and environmental wear and damage. Although these layers contain many materials they are primarily composed of mucin glycoproteins, the concentration of which may be physiologically controlled to maintain specific rheological properties and to provide proper lubrication. Nowhere is this truer than at the surface of the eye's corneal epithelium, where the mucous layer must additionally achieve structural integrity to withstand the stresses created by blinking, and remain transparent in order to enable vision. I will present results on the growth dynamics, concentration, and rheology of a model corneal epithelial mucous layer, all of which can be viewed as important parameters at this interface. I will also discuss modulation of the mucous layer's dynamics with variation in environmental conditions. Alcon.

Experimental infection of mice with tightly coiled spiral bacteria ("Candidatus Helicobacter suis") originating from the pig stomach.

PubMed

Park, J-H; Hong, J J; Park, J H

2003-01-01

Mice (n=34) were inoculated orally with a gastric homogenate from a pig infected with tightly coiled spiral bacteria (TCSB). In mice killed in pairs at 16 intervals up to 108 weeks post-inoculation (pi), TCSB were invariably found, mainly in the mucosal surface, gastric pits, intercellular spaces, cytoplasm of surface epithelial cells, and lumina of gastric glands. Histopathologically, infiltration of lymphocytes and plasma cells was seen from 8 weeks pi onwards, gradually increasing as infection progressed. From 64 weeks pi onwards, the formation of large follicles was observed in the lamina propria and submucosa, together with severe necrosis of surface epithelial cells. Glandular epithelial cells in the fundic mucosa were markedly dysplastic and intruded through the basement membrane into the submucosal layer. Common antigenicity between TCSB and Helicobacter pylori was demonstrated by Western blotting, ELISA, and immunohistochemistry. The sequence of the 16S rDNA fragment of 374 bp showed 100% homology with the 16S rRNA gene of "Candidatus Helicobacter suis". Experimental infection of the gastric mucosa of mice with TCSB was closely associated with chronic gastritis and dysplastic lesions.

Ocular surface changes in thyroid eye disease.

PubMed

Ismailova, Dilyara S; Fedorov, Anatoly A; Grusha, Yaroslav O

2013-04-01

To study the incidence and risk factors of ocular surface damage in thyroid eye disease (TED) and to determine histological changes underlying positive vital staining in this condition. Forty-six patients (92 eyes) with TED were included in this study. Routine ophthalmologic examination, Schirmer test I, vital staining and corneal sensitivity were performed. Fifteen patients with positive vital staining underwent impression cytology and incisional biopsy. Positive vital staining with lissamine green was observed in 56 eyes (60.9%), 30 patients (65.2%). The average degree of staining was 4.57 ± 0.44 (National Eye Institute Workshop grading system). Severe dry eye syndrome was found in 16%. The following histological changes of conjunctiva were revealed: significant epithelial dystrophy with cell polymorphism, goblet cells loss, excessive desquamation and epithelial keratinization with local leukocytic infiltration of substantia propria. According to our results dry eye syndrome is present in 65.2% of patients (60.9% eyes) with TED. Significant risk factors of ocular surface damage in TED were exophthalmos, lagophthalmos, palpebral fissure height and lower lid retraction. Positive conjunctival staining results from punctuate epithelial erosions and excessive desquamation of superficial cells. Histopathologic changes detected in conjunctiva consistent with dry eye and are not specific for TED.

Cell-to-Cell Contact and Nectin-4 Govern Spread of Measles Virus from Primary Human Myeloid Cells to Primary Human Airway Epithelial Cells.

PubMed

Singh, Brajesh K; Li, Ni; Mark, Anna C; Mateo, Mathieu; Cattaneo, Roberto; Sinn, Patrick L

2016-08-01

Measles is a highly contagious, acute viral illness. Immune cells within the airways are likely first targets of infection, and these cells traffic measles virus (MeV) to lymph nodes for amplification and subsequent systemic dissemination. Infected immune cells are thought to return MeV to the airways; however, the mechanisms responsible for virus transfer to pulmonary epithelial cells are poorly understood. To investigate this process, we collected blood from human donors and generated primary myeloid cells, specifically, monocyte-derived macrophages (MDMs) and dendritic cells (DCs). MDMs and DCs were infected with MeV and then applied to primary cultures of well-differentiated airway epithelial cells from human donors (HAE). Consistent with previous results obtained with free virus, infected MDMs or DCs were incapable of transferring MeV to HAE when applied to the apical surface. Likewise, infected MDMs or DCs applied to the basolateral surface of HAE grown on small-pore (0.4-μm) support membranes did not transfer virus. In contrast, infected MDMs and DCs applied to the basolateral surface of HAE grown on large-pore (3.0-μm) membranes successfully transferred MeV. Confocal microscopy demonstrated that MDMs and DCs are capable of penetrating large-pore membranes but not small-pore membranes. Further, by using a nectin-4 blocking antibody or recombinant MeV unable to enter cells through nectin-4, we demonstrated formally that transfer from immune cells to HAE occurs in a nectin-4-dependent manner. Thus, both infected MDMs and DCs rely on cell-to-cell contacts and nectin-4 to efficiently deliver MeV to the basolateral surface of HAE. Measles virus spreads rapidly and efficiently in human airway epithelial cells. This rapid spread is based on cell-to-cell contact rather than on particle release and reentry. Here we posit that MeV transfer from infected immune cells to epithelial cells also occurs by cell-to-cell contact rather than through cell-free particles. In addition, we sought to determine which immune cells transfer MeV infectivity to the human airway epithelium. Our studies are based on two types of human primary cells: (i) myeloid cells generated from donated blood and (ii) well-differentiated airway epithelial cells derived from donor lungs. We show that different types of myeloid cells, i.e., monocyte-derived macrophages and dendritic cells, transfer infection to airway epithelial cells. Furthermore, cell-to-cell contact is an important component of successful MeV transfer. Our studies elucidate a mechanism by which the most contagious human respiratory virus is delivered to the airway epithelium. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Epithelial Markers aSMA, Krt14, and Krt19 Unveil Elements of Murine Lacrimal Gland Morphogenesis and Maturation.

PubMed

Kuony, Alison; Michon, Frederic

2017-01-01

As an element of the lacrimal apparatus, the lacrimal gland (LG) produces the aqueous part of the tear film, which protects the eye surface. Therefore, a defective LG can lead to serious eyesight impairment. Up to now, little is known about LG morphogenesis and subsequent maturation. In this study, we delineated elements of the cellular and molecular events involved in LG formation by using three epithelial markers, namely aSMA, Krt14, and Krt19. While aSMA marked a restricted epithelial population of the terminal end buds (TEBs) in the forming LG, Krt14 was found in the whole embryonic LG epithelial basal cell layer. Interestingly, Krt19 specifically labeled the presumptive ductal domain and subsequently, the luminal cell layer. By combining these markers, the Fucci reporter mouse strain and genetic fate mapping of the Krt14 + population, we demonstrated that LG epithelium expansion is fuelled by a patterned cell proliferation, and to a lesser extent by epithelial reorganization and possible mesenchymal-to-epithelial transition. We pointed out that this epithelial reorganization, which is associated with apoptosis, regulated the lumen formation. Finally, we showed that the inhibition of Notch signaling prevented the ductal identity from setting, and led to a LG covered by ectopic TEBs. Taken together our results bring a deeper understanding on LG morphogenesis, epithelial domain identity, and organ expansion.

Epithelial Markers aSMA, Krt14, and Krt19 Unveil Elements of Murine Lacrimal Gland Morphogenesis and Maturation

PubMed Central

Kuony, Alison; Michon, Frederic

2017-01-01

As an element of the lacrimal apparatus, the lacrimal gland (LG) produces the aqueous part of the tear film, which protects the eye surface. Therefore, a defective LG can lead to serious eyesight impairment. Up to now, little is known about LG morphogenesis and subsequent maturation. In this study, we delineated elements of the cellular and molecular events involved in LG formation by using three epithelial markers, namely aSMA, Krt14, and Krt19. While aSMA marked a restricted epithelial population of the terminal end buds (TEBs) in the forming LG, Krt14 was found in the whole embryonic LG epithelial basal cell layer. Interestingly, Krt19 specifically labeled the presumptive ductal domain and subsequently, the luminal cell layer. By combining these markers, the Fucci reporter mouse strain and genetic fate mapping of the Krt14+ population, we demonstrated that LG epithelium expansion is fuelled by a patterned cell proliferation, and to a lesser extent by epithelial reorganization and possible mesenchymal-to-epithelial transition. We pointed out that this epithelial reorganization, which is associated with apoptosis, regulated the lumen formation. Finally, we showed that the inhibition of Notch signaling prevented the ductal identity from setting, and led to a LG covered by ectopic TEBs. Taken together our results bring a deeper understanding on LG morphogenesis, epithelial domain identity, and organ expansion. PMID:29033846

Externalization of phosphatidylserine via multidrug resistance 1 (MDR1)/P-glycoprotein in oxalate-treated renal epithelial cells: implications for calcium oxalate urolithiasis.

PubMed

Li, Yu-Hang; Yu, Shi-Liang; Gan, Xiu-Guo; Pan, Shang-Ha; Teng, Yue-Qiu; An, Rui-Hua

2016-02-01

We investigated the possible involvement of multidrug resistance protein 1 P-glycoprotein (MDR1 P-gp) in the oxalate-induced redistribution of phosphatidylserine in renal epithelial cell membranes. Real-time PCR and western blotting were used to examine MDR1 expression in Madin-Darby canine kidney cells at the mRNA and protein levels, respectively, whereas surface-expressed phosphatidylserine was detected by the annexin V-binding assay. Oxalate treatment resulted in increased synthesis of MDR1, which resulted in phosphatidylserine (PS) externalization in the renal epithelial cell membrane. Treatment with the MDR1 inhibitor PSC833 significantly attenuated phosphatidylserine externalization. Transfection of the human MDR1 gene into renal epithelial cells significantly increased PS externalization. To our knowledge, this study is the first to show that oxalate increases the synthesis of MDR1 P-gp, which plays a key role in hyperoxaluria-promoted calcium oxalate urolithiasis by facilitating phosphatidylserine redistribution in renal epithelial cells.

Bifidobacterium breve reduces apoptotic epithelial cell shedding in an exopolysaccharide and MyD88-dependent manner

PubMed Central

Hughes, K. R.; Harnisch, L. C.; Alcon-Giner, C.; Mitra, S.; Wright, C. J.; Ketskemety, J.

2017-01-01

Certain members of the microbiota genus Bifidobacterium are known to positively influence host well-being. Importantly, reduced bifidobacterial levels are associated with inflammatory bowel disease (IBD) patients, who also have impaired epithelial barrier function, including elevated rates of apoptotic extrusion of small intestinal epithelial cells (IECs) from villi—a process termed ‘cell shedding’. Using a mouse model of pathological cell shedding, we show that mice receiving Bifidobacterium breve UCC2003 exhibit significantly reduced rates of small IEC shedding. Bifidobacterial-induced protection appears to be mediated by a specific bifidobacterial surface exopolysaccharide and interactions with host MyD88 resulting in downregulation of intrinsic and extrinsic apoptotic responses to protect epithelial cells under highly inflammatory conditions. Our results reveal an important and previously undescribed role for B. breve, in positively modulating epithelial cell shedding outcomes via bacterial- and host-dependent factors, supporting the notion that manipulation of the microbiota affects intestinal disease outcomes. PMID:28123052

Bifidobacterium breve reduces apoptotic epithelial cell shedding in an exopolysaccharide and MyD88-dependent manner.

PubMed

Hughes, K R; Harnisch, L C; Alcon-Giner, C; Mitra, S; Wright, C J; Ketskemety, J; van Sinderen, D; Watson, A J M; Hall, L J

2017-01-01

Certain members of the microbiota genus Bifidobacterium are known to positively influence host well-being. Importantly, reduced bifidobacterial levels are associated with inflammatory bowel disease (IBD) patients, who also have impaired epithelial barrier function, including elevated rates of apoptotic extrusion of small intestinal epithelial cells (IECs) from villi-a process termed 'cell shedding'. Using a mouse model of pathological cell shedding, we show that mice receiving Bifidobacterium breve UCC2003 exhibit significantly reduced rates of small IEC shedding. Bifidobacterial-induced protection appears to be mediated by a specific bifidobacterial surface exopolysaccharide and interactions with host MyD88 resulting in downregulation of intrinsic and extrinsic apoptotic responses to protect epithelial cells under highly inflammatory conditions. Our results reveal an important and previously undescribed role for B. breve, in positively modulating epithelial cell shedding outcomes via bacterial- and host-dependent factors, supporting the notion that manipulation of the microbiota affects intestinal disease outcomes. © 2017 The Authors.

[Recurrent Corneal Erosions in Epithelial Corneal Dystrophies].

PubMed

Geerling, Gerd; Lisch, Walter; Finis, David

2018-06-01

The corneal epithelium is the most important structure of the ocular optical system. Recurrent corneal erosions can result from inflammation, trauma, degeneration and dystrophies. Epithelial basement membrane dystrophy (EBMD), epithelial recurrent erosion dystrophy (ERED) and Francheschetti and Meesmann's epithelial corneal dystrophy (MECD) can all - besides other signs and symptoms - result in more or less frequent corneal erosions. The pathomechanisms involved however are different. In EBMD, corneal erosions are facultative and clinical signs are often subtle. Aberrant basement membrane structures are associated with thinning of the epithelium and can be clinically identified as maps or fingerprints. In ERED, recurrent corneal erosions are - predominantly in the first decades of life - always present. A defect in the COL17A1 gene results in a dysfunctional hemidesmosome. In MECD, punctate corneal erosions are less frequent and result from intraepithelial microcysts which open spontaneously onto the ocular surface. Usually lubricants, therapeutic contact lenses and sometimes epithelial debridement and phototherapeutic keratectomy are the mainstay for treating corneal erosions in these three dystrophies. Georg Thieme Verlag KG Stuttgart · New York.

3D surface reconstruction and visualization of the Drosophila wing imaginal disc at cellular resolution

NASA Astrophysics Data System (ADS)

Bai, Linge; Widmann, Thomas; Jülicher, Frank; Dahmann, Christian; Breen, David

2013-01-01

Quantifying and visualizing the shape of developing biological tissues provide information about the morphogenetic processes in multicellular organisms. The size and shape of biological tissues depend on the number, size, shape, and arrangement of the constituting cells. To better understand the mechanisms that guide tissues into their final shape, it is important to investigate the cellular arrangement within tissues. Here we present a data processing pipeline to generate 3D volumetric surface models of epithelial tissues, as well as geometric descriptions of the tissues' apical cell cross-sections. The data processing pipeline includes image acquisition, editing, processing and analysis, 2D cell mesh generation, 3D contourbased surface reconstruction, cell mesh projection, followed by geometric calculations and color-based visualization of morphological parameters. In their first utilization we have applied these procedures to construct a 3D volumetric surface model at cellular resolution of the wing imaginal disc of Drosophila melanogaster. The ultimate goal of the reported effort is to produce tools for the creation of detailed 3D geometric models of the individual cells in epithelial tissues. To date, 3D volumetric surface models of the whole wing imaginal disc have been created, and the apicolateral cell boundaries have been identified, allowing for the calculation and visualization of cell parameters, e.g. apical cross-sectional area of cells. The calculation and visualization of morphological parameters show position-dependent patterns of cell shape in the wing imaginal disc. Our procedures should offer a general data processing pipeline for the construction of 3D volumetric surface models of a wide variety of epithelial tissues.

The insulin response integrates increased TGF-β signaling through Akt-induced enhancement of cell surface delivery of TGF-β receptors

PubMed Central

Budi, Erine H.; Muthusamy, Baby Periyanayaki; Derynck, Rik

2015-01-01

Increased activity of transforming growth factor β (TGF-β), which binds to and stimulates cell surface receptors, contributes to cancer progression and fibrosis by driving epithelial cells toward a migratory mesenchymal phenotype and increasing the abundance of extracellular matrix proteins. The abundance of TGF-β receptors at the cell surface determines cellular responsiveness to TGF-β, which is often produced by the same cells that have the receptors, and thus serves as an autocrine signal. We found that Akt-mediated phosphorylation of AS160, a RabGAP [guanosine triphosphatase (GTPase)-activating protein] promoted the translocation of TGF-β receptors from intracellular stores to the plasma membrane of mouse embryonic fibroblasts (MEFs) and NMuMG epithelial cells. Consequently, insulin, which is commonly used to treat hyperglycemia and activates Akt signaling, increased the amount of TGF-β receptors at the cell surface, thereby enhancing TGF-β responsiveness. This insulin-induced increase in autocrine TGF-β signaling contributed to insulin-induced gene expression responses, attenuated the epithelial phenotype, and promoted the migration of NMuMG cells. Furthermore, the enhanced delivery of TGF-β receptors at the cell surface enabled insulin to increase TGF-β-induced gene responses. The enhancement of TGF-β responsiveness in response to Akt activation may help to explain the biological effects of insulin, the progression of cancers in which Akt is activated, and the increased incidence of fibroses in diabetes. PMID:26420907

Correlation between the histological features of corneal surface pannus following ocular surface burns and the final outcome of cultivated limbal epithelial transplantation.

PubMed

Sati, Alok; Basu, Sayan; Sangwan, Virender S; Vemuganti, Geeta K

2015-04-01

To report the influence of histological features of corneal surface pannus following ocular surface burn on the outcome of cultivated limbal epithelial transplantation (CLET). On retrospectively reviewing the medical records of the patients who underwent autologous CLET from April 2002 to June 2012 at L V Prasad Eye Institute, Hyderabad, India, we could trace the histological reports in only 90 records. These 90 records, besides clinical parameters, were reviewed for the influence of various histological features on the final outcome of CLET. The histological features include epithelial hyperplasia (21.1%), surface ulceration (2.2%), goblet cells (62.2%), squamous metaplasia (11.1%), active fibrosis (31.1%), severe inflammation (8.9%), multinucleated giant cells (3.3%), stromal calcification (8.9%) and active proliferating vessels (5.6%). Among these histological features, patients with either hyperplasia or calcification in their excised corneal pannus show an unfavourable outcome compared with patients without hyperplasia (p=0.003) or calcification (p=0.018). A similar unfavourable outcome was not seen with other histological features and various clinical parameters. Presence of either calcific deposits or hyperplasia in the excised corneal pannus provides poor prognostication; hence, a proper counselling of such patients is mandatory along with a close follow-up. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Alkaline phosphatase, 5'-nucleotidase and magnesium-dependent adenosine triphosphatase activities in the transitional epithelium of the rat urinary bladder.

PubMed

Zhang, S X; Kobayashi, T; Okada, T; García del Saz, E; Seguchi, H

1991-07-01

The cerium-based method was used to demonstrate cytochemically the ultrastructural localization of alkaline phosphatase (ALPase), 5'-nucleotidase (5'-Nase) and magnesium-dependent adenosine triphosphatase (Mg-ATPase) on the transitional epithelium of the rat urinary bladder. The reaction product for ALPase was found on the plasma membrane of all epithelial cells, except the luminal surface of superficial cells. The activity of 5'-Nase appeared on the plasma membrane of all bladder transitional epithelial cells, including the free surface of superficial cells. The Mg-ATPase reaction product was seen on the plasma membrane of superficial, intermediate and basal cells, but never on the luminal surface of superficial cells and it was only occasionally seen on the basal surface. The possible functions of these phosphatases have been discussed, and it was emphasized that the 5'-Nase activity present on the luminal surface of superficial cells may play a special role in the membrane movement of these cells in the transitional epithelium.

Fabrication of corneal epithelial cell sheets maintaining colony-forming cells without feeder cells by oxygen-controlled method.

PubMed

Nakajima, Ryota; Takeda, Shizu

2014-01-01

The use of murine 3T3 feeder cells needs to be avoided when fabricating corneal epithelial cell sheets for use in treating ocular surface diseases. However, the expression level of the epithelial stem/progenitor cell marker, p63, is down-regulated in feeder-free culture systems. In this study, in order to fabricate corneal epithelial cell sheets that maintain colony-forming cells without using any feeder cells, we investigated the use of an oxygen-controlled method that was developed previously to fabricate cell sheets efficiently. Rabbit limbal epithelial cells were cultured under hypoxia (1-10% O2) and under normoxia during stratification after reaching confluence. Multilayered corneal epithelial cell sheets were fabricated using an oxygen-controlled method, and immunofluorescence analysis showed that cytokeratin 3 and p63 was expressed in appropriate localization in the cell sheets. The colony-forming efficiency of the cell sheets fabricated by the oxygen-controlled method without feeder cells was significantly higher than that of cell sheets fabricated under 20% O2 without feeder cells. These results indicate that the oxygen-controlled method has the potential to achieve a feeder-free culture system for fabricating corneal epithelial cell sheets for corneal regeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Methylene Blue Assay for Estimation of Regenerative Re-Epithelialization In Vivo.

PubMed

Milyavsky, Maresha; Dickie, Renee

2017-02-01

The rapidity with which epithelial cells cover a wound surface helps determine whether scarring or scar-less healing results. As methylene blue is a vital dye that is absorbed by damaged tissue but not undamaged epidermis, it can be used to assess wound closure. We sought to develop a quantitative methylene blue exclusion assay to estimate the timeframe for re-epithelialization in regenerating appendages in zebrafish and axolotls, two classic model systems of regeneration. Following application of methylene blue to the amputation plane and extensive washing, the regenerating tail was imaged in vivo until staining was no longer visible. The percent area of the amputation plane positive for methylene blue, representing the area of the amputation plane not yet re-epithelialized, was measured for each time point. The loss of methylene blue occurred rapidly, within ~2.5 h in larval and juvenile axolotls and <1 h in adult zebrafish, consistent with high rates of re-epithelialization in these models of regeneration. The assay allows simple, rapid estimation of the time course for regenerative re-epithelialization without affecting subsequent regenerative ability. This technique will permit comparison of re-epithelialization across different strains and stages, as well as under the influence of various pharmacological inhibitors that affect regeneration.

Antimicrobial aspects of inflammatory resolution in the mucosa: A role for pro-resolving mediators1

PubMed Central

Campbell, Eric L.; Serhan, Charles N.; Colgan, Sean P.

2011-01-01

Mucosal surfaces function as selectively permeable barriers between the host and the outside world. Given their close proximity to microbial antigens, mucosal surfaces have evolved sophisticated mechanisms for maintaining homeostasis and preventing excessive acute inflammatory reactions. The role attributed to epithelial cells was historically limited to serving as a selective barrier, in recent years numerous findings implicate an active role of the epithelium with pro-resolving mediators in the maintenance of immunological equilibrium. In this brief review, we highlight new evidence that the epithelium actively contributes to coordination and resolution of inflammation, principally through the generation of anti-inflammatory and pro-resolution lipid mediators. These autacoids, derived from ω-6 and ω-3 polyunsaturated fatty acids, are implicated in the initiation, progression and resolution of acute inflammation and display specific, epithelial-directed actions focused on mucosalhomeostasis. We also summarize present knowledge of mechanisms for resolution via regulation of epithelial-derived antimicrobial peptides in response to pro-resolving lipid mediators. PMID:21934099

Calcium-activated chloride channel TMEM16A modulates mucin secretion and airway smooth muscle contraction.

PubMed

Huang, Fen; Zhang, Hongkang; Wu, Meng; Yang, Huanghe; Kudo, Makoto; Peters, Christian J; Woodruff, Prescott G; Solberg, Owen D; Donne, Matthew L; Huang, Xiaozhu; Sheppard, Dean; Fahy, John V; Wolters, Paul J; Hogan, Brigid L M; Finkbeiner, Walter E; Li, Min; Jan, Yuh-Nung; Jan, Lily Yeh; Rock, Jason R

2012-10-02

Mucous cell hyperplasia and airway smooth muscle (ASM) hyperresponsiveness are hallmark features of inflammatory airway diseases, including asthma. Here, we show that the recently identified calcium-activated chloride channel (CaCC) TMEM16A is expressed in the adult airway surface epithelium and ASM. The epithelial expression is increased in asthmatics, particularly in secretory cells. Based on this and the proposed functions of CaCC, we hypothesized that TMEM16A inhibitors would negatively regulate both epithelial mucin secretion and ASM contraction. We used a high-throughput screen to identify small-molecule blockers of TMEM16A-CaCC channels. We show that inhibition of TMEM16A-CaCC significantly impairs mucus secretion in primary human airway surface epithelial cells. Furthermore, inhibition of TMEM16A-CaCC significantly reduces mouse and human ASM contraction in response to cholinergic agonists. TMEM16A-CaCC blockers, including those identified here, may positively impact multiple causes of asthma symptoms.

Virus interaction with the apical junctional complex.

PubMed

Gonzalez-Mariscal, Lorenza; Garay, Erika; Lechuga, Susana

2009-01-01

In order to infect pathogens must breach the epithelial barriers that separate the organism from the external environment or that cover the internal cavities and ducts of the body. Epithelia seal the passage through the paracellular pathway with the apical junctional complex integrated by tight and adherens junctions. In this review we describe how viruses like coxsackie, swine vesicular disease virus, adenovirus, reovirus, feline calcivirus, herpes viruses 1 and 2, pseudorabies, bovine herpes virus 1, poliovirus and hepatitis C use as cellular receptors integral proteins present at the AJC of epithelial cells. Interaction with these proteins contributes in a significant manner in defining the particular tropism of each virus. Besides these proteins, viruses exhibit a wide range of cellular co-receptors among which proteins present in the basolateral cell surface like integrins are often found. Therefore targeting proteins of the AJC constitutes a strategy that might allow viruses to bypass the physical barrier that blocks their access to receptors expressed on the basolateral surface of epithelial cells.

Biological effects of carbon black nanoparticles are changed by surface coating with polycyclic aromatic hydrocarbons.

PubMed

Lindner, Karina; Ströbele, Michael; Schlick, Sandra; Webering, Sina; Jenckel, André; Kopf, Johannes; Danov, Olga; Sewald, Katherina; Buj, Christian; Creutzenberg, Otto; Tillmann, Thomas; Pohlmann, Gerhard; Ernst, Heinrich; Ziemann, Christina; Hüttmann, Gereon; Heine, Holger; Bockhorn, Henning; Hansen, Tanja; König, Peter; Fehrenbach, Heinz

2017-03-21

Carbon black nanoparticles (CBNP) are mainly composed of carbon, with a small amount of other elements (including hydrogen and oxygen). The toxicity of CBNP has been attributed to their large surface area, and through adsorbing intrinsically toxic substances, such as polycyclic aromatic hydrocarbons (PAH). It is not clear whether a PAH surface coating changes the toxicological properties of CBNP by influencing their physicochemical properties, through the specific toxicity of the surface-bound PAH, or by a combination of both. Printex ® 90 (P90) was used as CBNP; the comparators were P90 coated with either benzo[a]pyrene (BaP) or 9-nitroanthracene (9NA), and soot from acetylene combustion that bears various PAHs on the surface (AS-PAH). Oxidative stress and IL-8/KC mRNA expression were determined in A549 and bronchial epithelial cells (16HBE14o-, Calu-3), mouse intrapulmonary airways and tracheal epithelial cells. Overall toxicity was tested in a rat inhalation study according to Organization for Economic Co-operation and Development (OECD) criteria. Effects on cytochrome monooxygenase (Cyp) mRNA expression, cell viability and mucociliary clearance were determined in acute exposure models using explanted murine trachea. All particles had similar primary particle size, shape, hydrodynamic diameter and ζ-potential. All PAH-containing particles had a comparable specific surface area that was approximately one third that of P90. AS-PAH contained a mixture of PAH with expected higher toxicity than BaP or 9NA. PAH-coating reduced some effects of P90 such as IL-8 mRNA expression and oxidative stress in A549 cells, granulocyte influx in the in vivo OECD experiment, and agglomeration of P90 and mucus release in the murine trachea ex vivo. Furthermore, P90-BaP decreased particle transport speed compared to P90 at 10 μg/ml. In contrast, PAH-coating induced IL-8 mRNA expression in bronchial epithelial cell lines, and Cyp mRNA expression and apoptosis in tracheal epithelial cells. In line with the higher toxicity compared to P90-BaP and P90-9NA, AS-PAH had the strongest biological effects both ex vivo and in vivo. Our results demonstrate that the biological effect of CBNP is determined by a combination of specific surface area and surface-bound PAH, and varies in different target cells.

Comparison of the effects of the CO2 laser and chlorohexidine on the sterilization of infected cutaneous wounds: a histologic study

NASA Astrophysics Data System (ADS)

Pinheiro, Antonio L. B.; das Neves, Jerlucia C.; de Castro, Jurema F. L.; Santos, Jose Z. L. V.; Ribeiro de Sena, Kesia X. d. F.; Brugnera, Aldo, Jr.; Zanin, Fatima A. A.

2001-04-01

Wound infection constitutes a big risk for patients and it is usually associated to increased morbidity, mortality and hospital costs. It is accepted that local treatment of these infections is effective. The aim of this study was to compare histologically the effects of the CO2 laser and Chlorohexidine Gluconate on Staphylococcus aureus infected cutaneous wounds. Standardized wounds were infected with Staphylococcus aureus and treated during six days as follows: Group I: Chlorohexidine Gluconate, 1 min, six days; Group II: CO2 Laser, one day, maintaining surface debris; Group III: CO2 Laser, one day, removing the surface debris. Seven days after wounding the animals were killed and specimens taken for light microscopy. On control wounds, it was observed epithelial ulceration, and neutrophylic and lymphoplasmocitary inflammatory infiltrate. On group II, there was epithelial hyperplasia, areas of ulceration and intense neutrophylic and lymphoplasmocitary inflammatory infiltrate. On the other hand, on group III, there was a neutrophylic inflammatory infiltrate underneath the surface debris and below that intense lymphoplasmocitary inflammatory infiltrate. When the surface debris was removed, there was epithelial ulceration and mild lymphoplasmocitary inflammatory infiltrate and fibroblasts and collagen fibers. The result of this study shows that infected wounds treated with 4 percent Chlorohexidine shows a more pronounced inflammatory reaction when compared to that observed when the CO2 Laser is used, especially when surface debris are removed; Surface debris removal on Laser treated wounds results ona better and quicker healing; the surface debris may act as a culture medium for bacterial growth, or because of its characteristics, it may act as local irritant and delay healing.

Percutaneous connectors

NASA Technical Reports Server (NTRS)

Picha, G. J.; Taylor, S. R.

1981-01-01

A surface possessing a regular array of micro-pillars was evaluated with regard to its ability to control epithelial downgrowth at the percutaneous interface. A range of pillar sizes were applied to the vertical segment of T shaped Biomer (R) implants. These percutaneous tabs were implanted into the dorsum of cats for a period of 6 weeks using a standardized surgical technique. Comments were made post-operatively and at the time of retrieval. A quantitative scoring system was applied to these observations as well as histological results. As observed, the pillar morphology used displayed the ability to control epithelial downgrowth. Collagen ingrowth into the interpillar spaces and possibly direct interactions of the epithelial cells with the morphology may account for the inhibition. The reproducibility of epithelial inhibition is, however, limited by other factors which are currently not well understood. These factors and potential methods of assessment are discussed.

Soluble fragments of e-cadherin cell-adhesion molecule increase in urinary-excretion of cancer-patients, potentially indicating its shedding from epithelial tumor-cells.

PubMed

Katayama, M; Hirai, S; Yasumoto, M; Nishikawa, K; Nagata, S; Otsuka, M; Kamihagi, K; Kato, I

1994-11-01

E-cadherin (Ecad) is well known to be a calcium-ion-dependent cell-cell adhesion molecule expressed mostly in epithelial tissues. Previous immunohistochemical studies suggested that this cell adhesion molecule acts as an invasion suppressor and is negligibly detected in cancer metastatic regions. Soluble Ecad fragments derived from the proteolysed membrane-associated form were detected in culture supernatants of two cell lines, COLO 205 and A-431, with normal distribution of cell surface Ecad. Soluble Ecad levels released into culture of COLO 205 exhibiting reduced cell-cell adhesion were apparently elevated above those of A-431 with tight cell-cell adhesion. Furthermore, human circulation and urine continuously contain soluble Ecad which consists mainly of homogeneous 75-85 kDa extracellular domains. Soluble Ecad urinary level per urinary creatinine level was found to be significantly elevated in 53% of patients suffering from various types of cancers including lung, liver, stomach, colon and rectal cancers, as compared with those in the age-matched healthy subjects. These results suggest that dysfunction of cell surface Ecad is responsible for its enhanced proteolytic shedding in tumorigenesis, which may lead to the decrease of cell surface Ecads. Furthermore, excretion of high levels of soluble Ecad fragments potentially indicates the progression of epithelial tumors excessively degrading cell surface Ecad in clinical subjects.

Posterior midgut epithelial cells differ in their organization of the membrane skeleton from other drosophila epithelia.

PubMed

Baumann, O

2001-11-01

In epithelial cells, the various components of the membrane skeleton are segregated within specialized subregions of the plasma membrane, thus contributing to the development and stabilization of cell surface polarity. It has previously been shown that, in various Drosophila epithelia, the membrane skeleton components ankyrin and alphabeta-spectrin reside at the lateral surface, whereas alphabeta(H)-spectrin is restricted to the apical domain. By use of confocal immunofluorescence microscopy, the present study characterizes the membrane skeleton of epithelial cells in the posterior midgut, leading to a number of unexpected results. First, ankyrin and alphabeta-spectrin are not detected on the entire lateral surface but appear to be restricted to the apicolateral area, codistributing with fasciclin III at smooth septate junctions. The presumptive ankyrin-binding proteins neuroglian and Na(+),K(+)-ATPase, however, do not colocalize with ankyrin. Second, alphabeta(H)-spectrin is enriched at the apical domain but is also present in lower amounts on the entire lateral surface, colocalizing apicolaterally with ankyrin/alphabeta-spectrin. Finally, despite the absence of zonulae adherentes, F-actin, beta(H)-spectrin, and nonmuscle myosin-II are enriched in the midlateral region. Thus, the model established for the organization of the membrane skeleton in Drosophila epithelia does not hold for the posterior midgut, and there is quite some variability between the different epithelia with respect to the organization of the membrane skeleton. Copyright 2001 Academic Press.

Follicle Depletion Provides a Permissive Environment for Ovarian Carcinogenesis

PubMed Central

Wang, Ying; Cai, Kathy Qi; Smith, Elizabeth R.; Yeasky, Toni M.; Moore, Robert; Ganjei-Azar, Parvin; Klein-Szanto, Andres J.; Godwin, Andrew K.; Hamilton, Thomas C.

2016-01-01

We modeled the etiology of postmenopausal biology on ovarian cancer risk using germ cell-deficient white-spotting variant (Wv) mice, incorporating oncogenic mutations. Ovarian cancer incidence is highest in peri- and postmenopausal women, and epidemiological studies have established the impact of reproductive factors on ovarian cancer risk. Menopause as a result of ovarian follicle depletion is thought to contribute to higher cancer risk. As a consequence of follicle depletion, female Wv mice develop ovarian tubular adenomas, a benign epithelial tumor corresponding to surface epithelial invaginations and papillomatosis frequently found in postmenopausal human ovaries. Lineage tracing using MISR2-Cre indicated that the tubular adenomas that developed in Wv mice were largely derived from the MISR2 lineage, which marked only a fraction of ovarian surface and oviduct epithelial cells in wild-type tissues. Deletion of p27, either heterozygous or homozygous, was able to convert the benign tubular adenomas into more proliferative tumors. Restricted deletion of p53 in Wv/Wv mice by either intrabursal injection of adenoviral Cre or inclusion of the MISR2-Cre transgene also resulted in augmented tumor growth. This finding suggests that follicle depletion provides a permissive ovarian environment for oncogenic transformation of epithelial cells, presenting a mechanism for the increased ovarian cancer risk in postmenopausal women. PMID:27354067

Three-dimensional epithelial tissues generated from human embryonic stem cells.

PubMed

Hewitt, Kyle J; Shamis, Yulia; Carlson, Mark W; Aberdam, Edith; Aberdam, Daniel; Garlick, Jonathan A

2009-11-01

The use of pluripotent human embryonic stem (hES) cells for tissue engineering may provide advantages over traditional sources of progenitor cells because of their ability to give rise to multiple cell types and their unlimited expansion potential. We derived cell populations with properties of ectodermal and mesenchymal cells in two-dimensional culture and incorporated these divergent cell populations into three-dimensional (3D) epithelial tissues. When grown in specific media and substrate conditions, two-dimensional cultures were enriched in cells (EDK1) with mesenchymal morphology and surface markers. Cells with a distinct epithelial morphology (HDE1) that expressed cytokeratin 12 and beta-catenin at cell junctions became the predominant cell type when EDK1 were grown on surfaces enriched in keratinocyte-derived extracellular matrix proteins. When these cells were incorporated into the stromal and epithelial tissue compartments of 3D tissues, they generated multilayer epithelia similar to those generated with foreskin-derived epithelium and fibroblasts. Three-dimensional tissues demonstrated stromal cells with morphologic features of mature fibroblasts, type IV collagen deposition in the basement membrane, and a stratified epithelium that expressed cytokeratin 12. By deriving two distinct cell lineages from a common hES cell source to fabricate complex tissues, it is possible to explore environmental cues that will direct hES-derived cells toward optimal tissue form and function.

Desialylation of Spermatozoa and Epithelial Cell Glycocalyx Is a Consequence of Bacterial Infection of the Epididymis*

PubMed Central

Khosravi, Farhad; Michel, Vera; Galuska, Christina E.; Bhushan, Sudhanshu; Christian, Philipp; Schuppe, Hans-Christian; Pilatz, Adrian; Galuska, Sebastian P.; Meinhardt, Andreas

2016-01-01

Urinary tract infections caused by uropathogenic Escherichia coli (UPEC) pathovars belong to the most frequent infections in humans. In men, pathogens can also spread to the genital tract via the continuous ductal system, eliciting bacterial prostatitis and/or epididymo-orchitis. Antibiotic treatment usually clears pathogens in acute epididymitis; however, the fertility of patients can be permanently impaired. Because a premature acrosome reaction was observed in an UPEC epididymitis mouse model, and sialidases on the sperm surface are considered to be activated via proteases of the acrosome, we aimed to investigate whether alterations of the sialome of epididymal spermatozoa and surrounding epithelial cells occur during UPEC infection. In UPEC-elicited acute epididymitis in mice, a substantial loss of N-acetylneuraminic acid residues was detected in epididymal spermatozoa and epithelial cells using combined laser microdissection/HPLC-ESI-MS analysis. In support, a substantial reduction of sialic acid residues bound to the surface of spermatozoa was documented in men with a recent history of E. coli-associated epididymitis. In vitro, such an UPEC induced N-acetylneuraminic acid release from human spermatozoa was effectively counteracted by a sialidase inhibitor. These findings strongly suggest a substantial remodeling of the glycocalyx of spermatozoa and epididymal epithelial cells by endogenous sialidases after a premature acrosome reaction during acute epididymitis. PMID:27339898

Effects of Exposure to Ozone on the Ocular Surface in an Experimental Model of Allergic Conjunctivitis

PubMed Central

Lee, Hun; Kim, Eung Kweon; Kim, Hee Young; Kim, Tae-im

2017-01-01

Based on previous findings that ozone can induce an inflammatory response in the ocular surface of an animal model and in cultured human conjunctival epithelial cells, we investigated whether exposure to ozone exacerbates symptoms of allergic conjunctivitis. We evaluated the effects of exposure to ozone on conjunctival chemosis, conjunctival injection, corneal and conjunctival fluorescein staining scores, production of inflammatory cytokines in tears, and aqueous tear production in a mouse model of allergic conjunctivitis. To validate our in vivo results, we used interleukin (IL)-1α-pretreated conjunctival epithelial cells as an in vitro substitute for the mouse model. We evaluated whether exposure to ozone increased the inflammatory response and altered oxidative status and mitochondrial function in IL-1α-pretreated conjunctival epithelial cells. In the in vivo study, ozone induced increases in conjunctival chemosis, conjunctival injection, corneal and conjunctival fluorescein staining scores, and production of inflammatory cytokines, accompanied by a decrease in tear volume. In the in vitro study, exposure to ozone led to additional increases in IL-6 and tumor necrosis factor-α mRNA levels, which were already induced by treatment with IL-1α. Ozone did not induce any changes in cell viability. Pretreatment with IL-1α increased the expression of manganese superoxide dismutase, and exposure to ozone led to additional increments in the expression of this antioxidant enzyme. Ozone did not induce any changes in mitochondrial activity or expression of mitochondrial enzymes and proteins related to mitochondrial function, with the exception of phosphor-mammalian target of rapamycin. Treatment with butylated hydroxyanisole, a free radical scavenger, attenuated the ozone-induced increases in IL-6 expression in IL-1α-pretreated conjunctival epithelial cells. Therefore, we conclude that exposure to ozone exacerbates the detrimental effects on the integrity of the ocular surface caused by conjunctival allergic reactions, and further increases the inflammatory response in IL-1α-pretreated conjunctival epithelial cells. PMID:28046113

Impact of Targeted Ocean Observations for Improving Ocean Model Initialization for Coupled Hurricane Forecasting

NASA Astrophysics Data System (ADS)

Halliwell, G. R.; Srinivasan, A.; Kourafalou, V. H.; Yang, H.; Le Henaff, M.; Atlas, R. M.

2012-12-01

The accuracy of hurricane intensity forecasts produced by coupled forecast models is influenced by errors and biases in SST forecasts produced by the ocean model component and the resulting impact on the enthalpy flux from ocean to atmosphere that powers the storm. Errors and biases in fields used to initialize the ocean model seriously degrade SST forecast accuracy. One strategy for improving ocean model initialization is to design a targeted observing program using airplanes and in-situ devices such as floats and drifters so that assimilation of the additional data substantially reduces errors in the ocean analysis system that provides the initial fields. Given the complexity and expense of obtaining these additional observations, observing system design methods such as OSSEs are attractive for designing efficient observing strategies. A new fraternal-twin ocean OSSE system based on the HYbrid Coordinate Ocean Model (HYCOM) is used to assess the impact of targeted ocean profiles observed by hurricane research aircraft, and also by in-situ float and drifter deployments, on reducing errors in initial ocean fields. A 0.04-degree HYCOM simulation of the Gulf of Mexico is evaluated as the nature run by determining that important ocean circulation features such as the Loop Current and synoptic cyclones and anticyclones are realistically simulated. The data-assimilation system is run on a 0.08-degree HYCOM mesh with substantially different model configuration than the nature run, and it uses a new ENsemble Kalman Filter (ENKF) algorithm optimized for the ocean model's hybrid vertical coordinates. The OSSE system is evaluated and calibrated by first running Observing System Experiments (OSEs) to evaluate existing observing systems, specifically quantifying the impact of assimilating more than one satellite altimeter, and also the impact of assimilating targeted ocean profiles taken by the NOAA WP-3D hurricane research aircraft in the Gulf of Mexico during the Deepwater Horizon oil spill. OSSE evaluation and calibration is then performed by repeating these two OSEs with synthetic observations and comparing the resulting observing system impact to determine if it differs from the OSE results. OSSEs are first run to evaluate different airborne sampling strategies with respect to temporal frequency of flights and the horizontal separation of upper-ocean profiles during each flight. They are then run to assess the impact of releasing multiple floats and gliders. Evaluation strategy focuses on error reduction in fields important for hurricane forecasting such as the structure of ocean currents and eddies, upper ocean heat content distribution, and upper-ocean stratification.

Gestational form of Selenium in Free-Choice Mineral Mixes Affects Transcriptome Profiles of the Neonatal Calf Testis, Including those of Steroidogenic and Spermatogenic Pathways.

PubMed

Cerny, K L; Garbacik, S; Skees, C; Burris, W R; Matthews, J C; Bridges, P J

2016-01-01

In areas where soils are deficient in Selenium (Se), dietary supplementation of this trace mineral directly to cattle is recommended. Because Se status affects testosterone synthesis and frequency of sperm abnormalities, and the form of Se supplemented to cows affects tissue-specific gene expression, the objective of this study was to determine whether the form of Se consumed by cows during gestation would affect the expression of mRNAs that regulate steroidogenesis and/or spermatogenesis in the neonatal calf testis. Twenty-four predominantly Angus cows were assigned randomly to have individual, ad libitum, access of a mineral mix containing 35 ppm of Se in free-choice vitamin-mineral mixes as either inorganic (ISe), organic (OSe), or a 50/50 mix of ISe and OSe (MIX), starting 4 months prior to breeding and continuing throughout gestation. Thirteen male calves were born over a 3-month period (ISe, n = 5; OSe, n = 4; MIX, n = 4), castrated within 2 days of birth, and extracted testis RNA subjected to transcriptomal analysis by microarray (Affymetrix Bovine 1.0 ST arrays) and targeted gene expression analysis by real-time reverse-transcription PCR (RT-PCR) of mRNAs encoding proteins known to affect steroidogenesis and/or spermatogenesis. The form of dam Se affected (P < 0.05) the expression of 853 annotated genes, including 17 mRNAs putatively regulating steroidogenesis and/or spermatogenesis. Targeted RT-PCR analysis indicated that the expression of mRNA encoding proteins CYP2S1 (cytochrome P450, family 2, subfamily S, polypeptide 1), HSD17B7 (hydroxysteroid (17β) dehydrogenase 7), SULT1E1 (sulfotransferase family 1E, estrogen preferring, member 1), LDHA (lactate dehydrogenase A), CDK5R1 (cyclin-dependent kinase 5, regulatory subunit 1), and LEP (leptin) was affected (P < 0.05) by form of Se consumed by dams of developing bull calves, while AKR1C4 (aldo-keto reductase family 1, member C4) and CCND2 (cyclin D2) tended (P < 0.09) to be affected. Our results indicate that form of Se fed to dams during gestation affected the transcriptome of the neonatal calf testis. If these profiles are maintained throughout maturation, then the form of Se fed to dams may impact bull fertility and the development of Se form-dependent mineral mixes that target gestational development of the testis are warranted.

Epithelial Keratins Modulate cMet Expression and Signaling and Promote InlB-Mediated Listeria monocytogenes Infection of HeLa Cells.

PubMed

Cruz, Rui; Pereira-Castro, Isabel; Almeida, Maria T; Moreira, Alexandra; Cabanes, Didier; Sousa, Sandra

2018-01-01

The host cytoskeleton is a major target for bacterial pathogens during infection. In particular, pathogens usurp the actin cytoskeleton function to strongly adhere to the host cell surface, to induce plasma membrane remodeling allowing invasion and to spread from cell to cell and disseminate to the whole organism. Keratins are cytoskeletal proteins that are the major components of intermediate filaments in epithelial cells however, their role in bacterial infection has been disregarded. Here we investigate the role of the major epithelial keratins, keratins 8 and 18 (K8 and K18), in the cellular infection by Listeria monocytogenes . We found that K8 and K18 are required for successful InlB/cMet-dependent L. monocytogenes infection, but are dispensable for InlA/E-cadherin-mediated invasion. Both K8 and K18 accumulate at InlB-mediated internalization sites following actin recruitment and modulate actin dynamics at those sites. We also reveal the key role of K8 and K18 in HGF-induced signaling which occurs downstream the activation of cMet. Strikingly, we show here that K18, and at a less extent K8, controls the expression of cMet and other surface receptors such TfR and integrin β1, by promoting the stability of their corresponding transcripts. Together, our results reveal novel functions for major epithelial keratins in the modulation of actin dynamics at the bacterial entry sites and in the control of surface receptors mRNA stability and expression.

Ectophosphatase activity in Candida albicans influences fungal adhesion: study between HIV-positive and HIV-negative isolates.

PubMed

Portela, M B; Kneipp, L F; Ribeiro de Souza, I P; Holandino, C; Alviano, C S; Meyer-Fernandes, J R; de Araújo Soares, R M

2010-07-01

This study describes the expression of acidic ectophosphatase activity on twenty isolates of C. albicans from oral cavities of HIV-infected children (HIV+) and compares them with fifteen isolates from HIV-negative children (HIV-), as well as the fungal adhesion to epithelial cells and medical records. The activities were measured in intact cells grown in BHI medium for 48 h at 37 degrees C. Phosphatase activity was assayed at pH 5.5 using 4-methylumbelliferyl phosphate. Yeast adhesion was measured using the MA 104 epithelial cell line. Mean values of ectophosphatase activity were 610.27 +/- 166.36 and 241.25 +/- 78.96 picomoles 4-methylumbelliferone/h/10(7) cells for HIV+ and HIV- group, respectively (P = 0.049). No correlation between C. albicans enzyme activity from HIV children with viral load and CD4 percentual was observed. Yeasts with high enzyme activity, isolated from HIV+ children showed greater adherence than yeasts with basal levels of ectophosphatases from HIV- (Spearman correlation, r = 0.8). Surface phosphatase activity was apparently involved in the adhesion to host cells, as the enhanced attachment of C. albicans to host epithelial cells was reversed by pretreatment of yeast with sodium orthovanadate (1 mM), an acid phosphatase inhibitor. These results show that C. albicans from HIV+ has an ectophosphatase activity significantly higher than the other isolates. Yeasts expressing higher levels of surface phosphatase activity showed greater adhesion to epithelial cells. So, the activity of acidic surface phosphatases on these cells may contribute to the early mechanisms required for disease establishment.

A novel closed cell culture device for fabrication of corneal epithelial cell sheets.

PubMed

Nakajima, Ryota; Kobayashi, Toyoshige; Moriya, Noboru; Mizutani, Manabu; Kan, Kazutoshi; Nozaki, Takayuki; Saitoh, Kazuo; Yamato, Masayuki; Okano, Teruo; Takeda, Shizu

2015-11-01

Automation technology for cell sheet-based tissue engineering would need to optimize the cell sheet fabrication process, stabilize cell sheet quality and reduce biological contamination risks. Biological contamination must be avoided in clinical settings. A closed culture system provides a solution for this. In the present study, we developed a closed culture device called a cell cartridge, to be used in a closed cell culture system for fabricating corneal epithelial cell sheets. Rabbit limbal epithelial cells were cultured on the surface of a porous membrane with 3T3 feeder cells, which are separate from the epithelial cells in the cell cartridges and in the cell-culture inserts as a control. To fabricate the stratified cell sheets, five different thicknesses of the membranes which were welded to the cell cartridge, were examined. Multilayered corneal epithelial cell sheets were fabricated in cell cartridges that were welded to a 25 µm-thick gas-permeable membrane, which was similar to the results with the cell-culture inserts. However, stratification of corneal epithelial cell sheets did not occur with cell cartridges that were welded to 100-300 µm-thick gas-permeable membranes. The fabricated cell sheets were evaluated by histological analyses to examine the expression of corneal epithelial-specific markers. Immunohistochemical analyses showed that a putative stem cell marker, p63, a corneal epithelial differentiation maker, CK3, and a barrier function marker, Claudin-1, were expressed in the appropriate position in the cell sheets. These results suggest that the cell cartridge is effective for fabricating corneal epithelial cell sheets. Copyright © 2012 John Wiley & Sons, Ltd.

[The epithelial junctional zones of the anal canal and cervix uterus: the ultrastructure of tumors of these zones].

PubMed

Chernyĭ, A P; Iakovleva, N I

1990-01-01

Relationships between squamous and columnar epithelia in the anal canal and cervix uteri of postnatal period and fetus were studied. The transitional stratified epithelial lining, which is called junctional epithelium, is interposed between the mentioned epithelia. The junctional epithelium has variable numbers of layers of epidermoid cells, which differ from cells of atypical squamous epithelium by some ultrastructural features of the cytoskeleton and cell surface and by a low content of glycogen. The hypothesis on the physiological significance of this epithelium is proposed. Ultrastructural features of the cytoskeleton and cell surface suggest that anal basaloid carcinomas and some cervical squamous carcinomas may develop from so-called junctional epithelium.

Lead, selenium and nickel concentrations in epithelial ovarian cancer, borderline ovarian tumor and healthy ovarian tissues.

PubMed

Canaz, Emel; Kilinc, Metin; Sayar, Hamide; Kiran, Gurkan; Ozyurek, Eser

2017-09-01

Wide variation exists in ovarian cancer incidence rates suggesting the importance of environmental factors. Due to increasing environmental pollution, trace elements and heavy metals have drawn attention in studies defining the etiology of cancer, but scant data is available for ovarian cancer. Our aim was to compare the tissue concentrations of lead, selenium and nickel in epithelial ovarian cancer, borderline tumor and healthy ovarian tissues. The levels of lead, selenium and nickel were estimated using atomic absorption spectrophotometry in formalin-fixed paraffin-embedded tissue samples. Tests were carried out in 20 malignant epithelial ovarian cancer, 15 epithelial borderline tumor and 20 non-neoplastic healthy ovaries. Two samples were collected for borderline tumors, one from papillary projection and one from the smooth surface of cyst wall. Pb and Ni concentrations were found to be higher both in malignant and borderline tissues than those in healthy ovaries. Concentrations of Pb and Ni in malignant tissues, borderline papillary projections and capsular tissue samples were not different. Comparison of Se concentrations of malignant, borderline and healthy ovarian tissues did not reveal statistical difference. Studied metal levels were not found to be different in either papillary projection or in cyst wall of the borderline tumors. This study revealed the accumulation of lead and nickel in ovarian tissue is associated with borderline and malignant proliferation of the surface epithelium. Accumulation of these metals in epithelial ovarian cancer and borderline ovarian tumor has not been demonstrated before. Copyright © 2017 Elsevier GmbH. All rights reserved.

Ultrastructure of the endolymphatic sac in the larva of the japanese red-bellied newt Cynops pyrrhogaster

NASA Technical Reports Server (NTRS)

Gao, W.; Wiederhold, M.; Hejl, R.

1998-01-01

The ultrastructure of the endolymphatic sac (ES) of the late stage larva of the Japanese red-bellied newt, Cynops pyrrhogaster (stage 57), was examined by light and transmission electron microscopy. The two endolymphatic sacs are located at the dorsal-medial side of the otic vesicle on the dorsal-lateral side of the midbrain in the cranial cavity. The wall of the sac is composed of a layer of cubical epithelial cells with loose, interposed intercellular spaces. The sac contains a large luminal cavity, in which endolymph and numerous otoconia are present. The epithelial cells of different portions of the sac have a similar structure. These cells contain an abundance of cytoplasmic organelles, including ribosomes, Golgi complexes, and numerous vesicles. Two types of vesicles are found in the epithelial cells: the "floccular" vesicle and the "granular" vesicle. The floccular vesicles are located in the supra- and lateral-nuclear cytoplasm and contain floccular material. The granular vesicles have a fine granular substance and are usually situated apposed to the apical cell membrane. The granular vesicles are suggested to be secreted into the lumen, while the floccular vesicles are thought to be absorbed from the lumen and conveyed to the intercellular spaces by the epithelial cells. The apical surfaces of the epithelial cells bear numerous microvilli. Apparently floating cells, which bear long microvilli on the free surfaces, are observed in the lumen of the ES. Based on the fine structure, the function of the endolymphatic sac of the newt Cynops pyrrhogaster is discussed.

Environmental Statement on the Tactical Fighter Weapons Center (TFWC) Range Complex, Nellis Air Force Base

DTIC Science & Technology

1977-03-10

rKanqaQoo P4OSe 7-T -PALLID KANGAROO MOLUS IM p rVf ,CtojI8. - PALLID KANGAROO MOUSE WM 1)Pu * -of the Fali~ Kaniaaroo Mice FISH (Figures D-13, D-14...and sudden noises. Conclusive data on effects of booms on production are not available, but no change in milk production by one dairy herd was noted...press). Parker, J. B. and N. D. Bayley. 1960. Investigations on effects of aircraft sound on milk production of dairy cattle, 1957-1958. U.S. Dept. of

Applications of Signal Processing in Digital Communications. Appendix.

DTIC Science & Technology

1991-04-01

we get a separable alphabet with 128 vectors (see Fig. 3). Among It is seen that the effect of R on a two-dimencional vector hem, 32 have energy 3c 2...and 96 have energy b2 + 2c 2. is to rotate it by an angle 21r/M, and the effect of T is to The average energy is 1. exchange its components. This...Sh, S, are two elements of It, the intradistance set associ- generating the code are d.ose associated to nlane ritalins ated with the coset Si! Include

Resource Letter OSE-1: Observing Solar Eclipses

NASA Astrophysics Data System (ADS)

Pasachoff, Jay M.; Fraknoi, Andrew

2017-07-01

This Resource Letter provides a guide to the available literature, listing selected books, articles, and online resources about scientific, cultural, and practical issues related to observing solar eclipses. It is timely, given that a total solar eclipse will cross the continental United States on August 21, 2017. The next total solar eclipse path crossing the U.S. and Canada will be on April 8, 2024. In 2023, the path of annularity of an annular eclipse will cross Mexico, the United States, and Canada, with partial phases visible throughout those countries.

GSDO Program Hexavalent Chrome Alternatives: Final Pretreatments Test Report

NASA Technical Reports Server (NTRS)

Kessel, Kurt

2013-01-01

Hexavalent chrome free pretreatments should be considered for use on Ground Support Equipment (OSE) and Electrical Ground Support Equipment (EOSE). Both of the hexavalent chrome free pretreatments (Metalast TCP HF and SurTec 650C) evaluated by this project met, and in some instances exceeded, the requirements ofMIL-DTL-5541 "Chemical Conversion Coatings on Aluminum and Aluminum Alloys". For DC resistance measurements, both Metalast TCP HF and SurTec (!50C met initial requirements following assembly and in many cases continued to maintain passing readings for the duration of testing.

A Unified Two-Dimensional Approach to the Calculation of Three- Dimensional Hypersonic Flows, with Application to Bodies of Revolution

DTIC Science & Technology

1955-01-01

Congress approved-Mfarch 3, 1915, for the supervision and dlirction of the scientific study of tho problems of flight (U. S. Code, -title 50, see. 15 1...streamldines. With this iiiforia- portance, compared to ’,)ose associated with-the curs at are of tion. %c tire enabled to construt t the flo%% field... articles at anld C) and this situailtion would preclude the-pos- -Characteristics theory.-’I’lIiucomnf~xtibihit3 equiat ions relat- sibilit(i of Prandt l-M

Ocular surface alterations and in vivo confocal microscopic characteristics of corneas in patients with myasthenia gravis.

PubMed

Erkan Turan, Kadriye; Kocabeyoglu, Sibel; Bekircan-Kurt, Can Ebru; Bezci, Figen; Erdem-Ozdamar, Sevim; Irkec, Murat

2018-03-01

To evaluate ocular surface alterations and characteristics of corneal basal epithelium and subbasal nerves in patients with myasthenia gravis. Myasthenia gravis patients (n = 21) and healthy controls (n = 20) were enrolled. All participants underwent ocular surface testing in the following order: tear break-up time, lissamine green staining, Schirmer I test with anesthesia, and Ocular Surface Disease Index questionnaire. The Cochet-Bonnet esthesiometer was used to measure corneal sensitivity. Basal epithelial cells and subbasal nerves were evaluated using in vivo confocal microscopy. Myasthenia gravis patients had higher Ocular Surface Disease Index score (13.9 ± 15.0 vs 1.4 ± 2.2, p < 0.001) and lissamine green staining score (0.6 ± 0.4 vs 0.2 ± 0.4, p = 0.007). Break-up time score (9.3 ± 3.0 vs 9.9 ± 1.9, p = 0.481) and Schirmer I test score (16.5 ± 9.2 vs 19.3 ± 8.4, p = 0.323) did not differ significantly. Corneal sensation was 0.4 g/mm 2 in all eyes. Patients with myasthenia gravis had lower basal epithelial cell density (3775.7 ± 938.1 vs 4983.1 ± 608.5, p < 0.001) and total nerve density (1956.1 ± 373.3 vs 2277.9 ± 405.0, p = 0.012) and higher subbasal nerve tortuosity (1.9 ± 0.8 vs 1.6 ± 0.7, p = 0.007) than controls. A significant increase in Ocular Surface Disease Index scores was found with decreasing basal epithelial cell density (rho = -0.518, p = 0.001). There was a significantly moderate negative correlation between the duration of myasthenia gravis and the number of corneal nerves (rho = -0.497, p = 0.022). Significant alterations of basal epithelial cells and subbasal nerves were demonstrated in myasthenia gravis patients although there was no difference of corneal sensitivity between myasthenia gravis patients and healthy controls. Thus, it should be borne in mind that myasthenia gravis patients deserve further evaluation with regard to ocular surface disease.

Mucin characteristics of human corneal-limbal epithelial cells that exclude the rose bengal anionic dye.

PubMed

Argüeso, Pablo; Tisdale, Ann; Spurr-Michaud, Sandra; Sumiyoshi, Mika; Gipson, Ilene K

2006-01-01

Rose bengal is an organic anionic dye used to assess damage of the ocular surface epithelium in ocular surface disease. It has been proposed that mucins have a protective role, preventing rose bengal staining of normal ocular surface epithelial cells. The current study was undertaken to evaluate rose bengal staining in a human corneal-limbal epithelial (HCLE) cell line known to produce and glycosylate membrane-associated mucins. HCLE cells were grown to confluence in serum-free medium and switched to DMEM/F12 with 10% serum to promote differentiation. Immunolocalization of the membrane-associated mucins MUC1 and MUC16 and the T-antigen carbohydrate epitope was performed with the monoclonal antibodies HMFG-2 and OC125 and jacalin lectin, respectively. To assess dye uptake, cultures were incubated for 5 minutes with 0.1% rose bengal and photographed. To determine whether exclusion of negatively charged rose bengal requires a negative charge at the cell surface, cells were incubated with fluoresceinated cationized ferritin. The effect of hyperosmotic stress on rose bengal staining in vitro was evaluated by increasing the ion concentration (Ca+2 and Mg+2) in the rose bengal uptake assay. The cytoplasm and nucleus of confluent HCLE cells cultured in media without serum, lacking the expression of MUC16 but not MUC1, as well as human corneal fibroblasts, which do not express mucins, stained with rose bengal. Culture of HCLE cells in medium containing serum resulted in the formation of islands of stratified cells that excluded rose bengal. Apical cells of the stratified islands produced MUC16 and the T-antigen carbohydrate epitope on their apical surfaces. Colocalization experiments demonstrated that fluoresceinated cationized ferritin did not bind to these stratified cells, indicating that rose bengal is excluded from cells that lack negative charges. Increasing the amounts of divalent cations in the media reduced the cellular area protected against rose bengal uptake. These results indicate that stratification and differentiation of corneal epithelial cells, as measured by the capacity to produce the membrane-associated mucin MUC16 and the mucin-associated T-antigen carbohydrate on their apical surfaces provide protection against rose bengal penetrance in vitro and suggest a role for membrane-associated mucins and their oligosaccharides in the protection of ocular surface epithelia.

Mucin Characteristics of Human Corneal-Limbal Epithelial Cells that Exclude the Rose Bengal Anionic Dye

PubMed Central

Argüeso, Pablo; Tisdale, Ann; Spurr-Michaud, Sandra; Sumiyoshi, Mika; Gipson, Ilene K.

2005-01-01

Purpose Rose bengal is an organic anionic dye used to assess damage of the ocular surface epithelium in ocular surface disease. It has been proposed that mucins have a protective role, preventing rose bengal staining of normal ocular surface epithelial cells. The current study was undertaken to evaluate rose bengal staining in a human corneal-limbal epithelial (HCLE) cell line known to produce and glycosylate membrane-associated mucins. Methods HCLE cells were grown to confluence in serum-free medium and switched to DMEM/F12 with 10% serum to promote differentiation. Immunolocalization of the membrane-associated mucins MUC1 and MUC16 and the T-antigen carbohydrate epitope was performed with the monoclonal antibodies HMFG-2 and OC125 and jacalin lectin, respectively. To assess dye uptake, cultures were incubated for 5 minutes with 0.1% rose bengal and photographed. To determine whether exclusion of negatively charged rose bengal requires a negative charge at the cell surface, cells were incubated with fluoresceinated cationized ferritin. The effect of hyperosmotic stress on rose bengal staining in vitro was evaluated by increasing the ion concentration (Ca+2 and Mg+2) in the rose bengal uptake assay. Results The cytoplasm and nucleus of confluent HCLE cells cultured in media without serum, lacking the expression of MUC16 but not MUC1, as well as human corneal fibroblasts, which do not express mucins, stained with rose bengal. Culture of HCLE cells in medium containing serum resulted in the formation of islands of stratified cells that excluded rose bengal. Apical cells of the stratified islands produced MUC16 and the T-antigen carbohydrate epitope on their apical surfaces. Colocalization experiments demonstrated that fluoresceinated cationized ferritin did not bind to these stratified cells, indicating that rose bengal is excluded from cells that lack negative charges. Increasing the amounts of divalent cations in the media reduced the cellular area protected against rose bengal uptake. Conclusions These results indicate that stratification and differentiation of corneal epithelial cells, as measured by the capacity to produce the membrane-associated mucin MUC16 and the mucin-associated T-antigen carbohydrate on their apical surfaces provide protection against rose bengal penetrance in vitro and suggest a role for membrane-associated mucins and their oligosaccharides in the protection of ocular surface epithelia. PMID:16384952

TNFα promotes CAR-dependent migration of leukocytes across epithelial monolayers

PubMed Central

Morton, Penny E.; Hicks, Alexander; Ortiz-Zapater, Elena; Raghavan, Swetavalli; Pike, Rosemary; Noble, Alistair; Woodfin, Abigail; Jenkins, Gisli; Rayner, Emma; Santis, George; Parsons, Maddy

2016-01-01

Trans-epithelial migration (TEpM) of leukocytes during inflammation requires engagement with receptors expressed on the basolateral surface of the epithelium. One such receptor is Coxsackie and Adenovirus Receptor (CAR) that binds to Junctional Adhesion Molecule-like (JAM-L) expressed on leukocytes. Here we provide the first evidence that efficient TEpM of monocyte-derived THP-1 cells requires and is controlled by phosphorylation of CAR. We show that TNFα acts in a paracrine manner on epithelial cells via a TNFR1-PI3K-PKCδ pathway leading to CAR phosphorylation and subsequent transmigration across cell junctions. Moreover, we show that CAR is hyper-phosphorylated in vivo in acute and chronic lung inflammation models and this response is required to facilitate immune cell recruitment. This represents a novel mechanism of feedback between leukocytes and epithelial cells during TEpM and may be important in controlling responses to pro-inflammatory cytokines in pathological settings. PMID:27193388

5'-adenosine monophosphate is the neutrophil-derived paracrine factor that elicits chloride secretion from T84 intestinal epithelial cell monolayers.

PubMed Central

Madara, J L; Patapoff, T W; Gillece-Castro, B; Colgan, S P; Parkos, C A; Delp, C; Mrsny, R J

1993-01-01

Neutrophil transmigration across intestinal epithelia is thought to contribute to epithelial dysfunction and characterizes many inflammatory intestinal diseases. Neutrophils activated by factors, normally present in the lumen, release a neutrophil-derived secretagogue activity to which intestinal epithelia respond with an electrogenic chloride secretion, the transport event which underlies secretory diarrhea. Using sequential ultrafiltration, column chromatographic, and mass and Raman spectroscopic techniques, neutrophil-derived secretagogue was identified as 5'-AMP. Additional studies suggested that neutrophil-derived 5'-AMP is subsequently converted to adenosine at the epithelial cell surface by ecto-5'-nucleotidase and that adenosine subsequently activates intestinal secretion through adenosine receptors on the apical membrane of target intestinal epithelial cells. These findings suggest that this ATP metabolite may serve as a neutrophil-derived paracrine mediator that contributes to secretory diarrhea in states of intestinal inflammation. PMID:8486793

Gene Transfer by Guanidinium-Cholesterol Cationic Lipids into Airway Epithelial Cells in vitro and in vivo

NASA Astrophysics Data System (ADS)

Oudrhiri, Noufissa; Vigneron, Jean-Pierre; Peuchmaur, Michel; Leclerc, Tony; Lehn, Jean-Marie; Lehn, Pierre

1997-03-01

Synthetic vectors represent an attractive alternative approach to viral vectors for gene transfer, in particular into airway epithelial cells for lung-directed gene therapy for cystic fibrosis. Having recently found that guanidinium-cholesterol cationic lipids are efficient reagents for gene transfer into mammalian cell lines in vitro, we have investigated their use for gene delivery into primary airway epithelial cells in vitro and in vivo. The results obtained indicate that the lipid bis (guanidinium)-tren-cholesterol (BGTC) can be used to transfer a reporter gene into primary human airway epithelial cells in culture. Furthermore, liposomes composed of BGTC and dioleoyl phosphatidylethanolamine (DOPE) are efficient for gene delivery to the mouse airway epithelium in vivo. Transfected cells were detected both in the surface epithelium and in submucosal glands. In addition, the transfection efficiency of BGTC/DOPE liposomes in vivo was quantitatively assessed by using the luciferase reporter gene system.

Multifocal Epithelial Hyperplasia of Oral Cavity Expressing HPV 16 Gene: A Rare Entity

PubMed Central

Prabhat, M. P. V.; Raja Lakshmi, Chintamaneni; Sai Madhavi, N.; Bhavana, Sujana Mulk; Sarat, Gummadapu; Ramamohan, Kodali

2013-01-01

Focal epithelial hyperplasia is a rare contagious disease caused by human papilloma virus. Usually HPV involves either cutaneous or mucosal surfaces, whereas concomitant mucocutaneous involvement is extremely rare. We report such a unique case of multifocal epithelial hyperplasia involving multiple sites of oral cavity along with skin lesions in a 65-year-old female. We also discuss the probable multifactorial etiology and variable clinical presentations of the lesions, including evidence of HPV 16 expression, as detected by polymerase chain reaction. The present report illustrates the need for careful examination and prompt diagnosis of the disease, as it might be associated with high risk genotypes such as HPV 16 and 18. PMID:24455323

Lacritin and other new proteins of the lacrimal functional unit.

PubMed

McKown, Robert L; Wang, Ningning; Raab, Ronald W; Karnati, Roy; Zhang, Yinghui; Williams, Patricia B; Laurie, Gordon W

2009-05-01

The lacrimal functional unit (LFU) is defined by the 2007 International Dry Eye WorkShop as 'an integrated system comprising the lacrimal glands, ocular surface (cornea, conjunctiva and meibomian glands) and lids, and the sensory and motor nerves that connect them'. The LFU maintains a healthy ocular surface primarily through a properly functioning tear film that provides protection, lubrication, and an environment for corneal epithelial cell renewal. LFU cells express thousands of proteins. Over 200 new LFU proteins have been discovered in the last decade. Lacritin is a new LFU-specific growth factor in human tears that flows through ducts to target corneal epithelial cells on the ocular surface. When applied topically in rabbits, lacritin appears to increase the volume of basal tear secretion. Lacritin is one of only a handful of tear proteins preliminarily reported to be downregulated in blepharitis and in two dry eye syndromes. Computational analysis predicts an ordered C-terminal domain that binds the corneal epithelial cell surface proteoglycan syndecan-1 (SDC1) and is required for lacritin's low nanomolar mitogenic activity. The lacritin-binding site on the N-terminus of SDC1 is exposed by heparanase. Heparanase is constitutively expressed by the corneal epithelium and appears to be a normal constituent of tears. Binding triggers rapid signaling to downstream NFAT and mTOR. A wealth of other new proteins, originally designated as hypothetical when first identified by genomic sequencing, are expressed by the human LFU including: ALS2CL, ARHGEF19, KIAA1109, PLXNA1, POLG, WIPI1 and ZMIZ2. Their demonstrated or implied roles in human genetic disease or basic cellular functions are fuel for new investigation. Addressing topical areas in ocular surface physiology with new LFU proteins may reveal interesting new biological mechanisms and help get to the heart of ocular surface dysfunction.

Surface Wave Elastometry of the Cornea in Porcine and Human Donor Eyes

PubMed Central

Dupps, William J.; Netto, Marcelo V.; Herekar, Satish; Krueger, Ronald R.

2007-01-01

PURPOSE To introduce a nondestructive technique for characterization of corneal stiffness, determine measurement precision, and investigate comparative stiffness values along central, radial, and circumferential vectors in porcine corneas. The effects of epithelial debridement, relaxing incisions, and crosslink-mediated stiffening on surface wave velocity are also studied. METHODS A handheld prototype system was used to measure ultrasound surface wave propagation time between two fixed-distance transducers along a ten-position map. Repeatability was assessed with replicate measurements in 6 porcine corneas. In 12 porcine globes with controlled intraocular pressure (IOP), serial measurements were performed before and after epithelial removal, then after 250- and 750-μm-deep relaxing incisions. In human globes with constant intravitreal pressure, central wave velocity and transcorneal IOP measurements were compared before and after collagen cross-linking. RESULTS Measurement repeatability across all regions was between 2.2% and 8.1%. Epithelial removal resulted in increases in measured stiffness in 67% of eyes, but statistical power was insufficient to detect a systematic change. Wave velocity across a central incision decreased significantly after 250-μm keratotomy (P<.001), but did not undergo a significant further decrease with deeper keratotomy. Meridional stiffness changes consistent with coupling effects were detected after keratotomy. Surface wave velocity and transcorneal IOP measurements increased markedly after collagen cross-linking despite maintenance of a constant IOP. CONCLUSIONS Handheld corneal elastometry provides a repeatable measure of regional stiffness changes after relaxing incisions and collagen cross-linking in in vitro experiments. Surface wave elastometry allows focal assessment of corneal biomechanical properties that are relevant in refractive surgery, ectatic disease, and glaucoma. PMID:17269246

Ultrastructural analysis of oral exfoliated epithelial cells of tobacco smokers and betel nut chewers: A scanning electron microscopy study.

PubMed

Khan, Sameera Shamim; Shreedhar, Balasundari; Kamboj, Mala

2016-01-01

The study was undertaken to correlate epithelial surface pattern changes of oral exfoliated cells of tobacco smokers and betel nut chewers and also to compare them with patients of oral squamous cell carcinoma (OSCC) and healthy individuals. In this cross-sectional study, a total of fifty persons were included in the study, out of which thirty formed the study group (15 each tobacco smokers and betel nut chewers) and twenty formed the control group (ten each of OSCC patients - positive control and ten normal buccal mucosa - negative control). Their oral exfoliated cells were scraped, fixed, and studied under scanning electron microscope (SEM). The statistical analysis was determined using ANOVA, Tukey honestly significant difference, Chi-square test, and statistical SPASS software, P < 0.05. OSCC, Individual cell modifications, intercellular relationships and surface characteristics observed by scanning electron microscopy between OSCC, tobacco smokers, betel nut chewers compared to normal oral mucosa have been tabulated. In normal oral mucosa, cell surface morphology depends on the state of keratinization of the tissue. Thus, it could prove helpful in detecting any carcinomatous change at its incipient stage and also give an insight into the ultra-structural details of cellular differentiations in epithelial tissues.

Inhibition of Ultraviolet B-Induced Expression of the Proinflammatory Cytokines TNF-α and VEGF in the Cornea by Fucoxanthin Treatment in a Rat Model.

PubMed

Chen, Shiu-Jau; Lee, Ching-Ju; Lin, Tzer-Bin; Liu, Hsiang-Jui; Huang, Shuan-Yu; Chen, Jia-Zeng; Tseng, Kuang-Wen

2016-01-07

Ultraviolet B (UVB) irradiation is the most common cause of radiation damage to the eyeball and is a risk factor for human corneal damage. We determined the protective effect of fucoxanthin, which is a carotenoid found in common edible seaweed, on ocular tissues against oxidative UVB-induced corneal injury. The experimental rats were intravenously injected with fucoxanthin at doses of 0.5, 5 mg/kg body weight/day or with a vehicle before UVB irradiation. Lissamine green for corneal surface staining showed that UVB irradiation caused serious damage on the corneal surface, including severe epithelial exfoliation and deteriorated epithelial smoothness. Histopathological lesion examination revealed that levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF), significantly increased. However, pretreatment with fucoxanthin inhibited UVB radiation-induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UVB-induced damage. Moreover, significant preservation of the epithelial integrity and inhibition of stromal swelling were also observed after UVB irradiation in fucoxanthin-treated groups. Pretreatment with fucoxanthin may protect against UVB radiation-induced corneal disorders by inhibiting expression of proinflammatory factors, TNF-α, and VEGF and by blocking polymorphonuclear leukocyte infiltration.

Commensal Bacteria Modulate Innate Immune Responses of Vaginal Epithelial Cell Multilayer Cultures

PubMed Central

Rose, William A.; McGowin, Chris L.; Spagnuolo, Rae Ann; Eaves-Pyles, Tonyia D.; Popov, Vsevolod L.; Pyles, Richard B.

2012-01-01

The human vaginal microbiome plays a critical but poorly defined role in reproductive health. Vaginal microbiome alterations are associated with increased susceptibility to sexually-transmitted infections (STI) possibly due to related changes in innate defense responses from epithelial cells. Study of the impact of commensal bacteria on the vaginal mucosal surface has been hindered by current vaginal epithelial cell (VEC) culture systems that lack an appropriate interface between the apical surface of stratified squamous epithelium and the air-filled vaginal lumen. Therefore we developed a reproducible multilayer VEC culture system with an apical (luminal) air-interface that supported colonization with selected commensal bacteria. Multilayer VEC developed tight-junctions and other hallmarks of the vaginal mucosa including predictable proinflammatory cytokine secretion following TLR stimulation. Colonization of multilayers by common vaginal commensals including Lactobacillus crispatus, L. jensenii, and L. rhamnosus led to intimate associations with the VEC exclusively on the apical surface. Vaginal commensals did not trigger cytokine secretion but Staphylococcus epidermidis, a skin commensal, was inflammatory. Lactobacilli reduced cytokine secretion in an isolate-specific fashion following TLR stimulation. This tempering of inflammation offers a potential explanation for increased susceptibility to STI in the absence of common commensals and has implications for testing of potential STI preventatives. PMID:22412914

The polymeric immunoglobulin receptor (secretory component) mediates transport of immune complexes across epithelial cells: a local defense function for IgA.

PubMed Central

Kaetzel, C S; Robinson, J K; Chintalacharuvu, K R; Vaerman, J P; Lamm, M E

1991-01-01

The polymeric immunoglobulin receptor (pIgR) on mucosal epithelial cells binds dimeric IgA (dIgA) on the basolateral surface and mediates transport of dIgA to the apical surface. Using Madin-Darby canine kidney epithelial cells stably transfected with pIgR cDNA, we found that soluble immune complexes (ICs) of 125I-labeled rat monoclonal antidinitrophenyl (DNP) dIgA (125I-dIgA) and DNP/biotin-bovine serum albumin were transported from the basolateral to the apical surface and then released. Monomeric IgA ICs were not transported, consistent with the specificity of pIgR for polymeric immunoglobulins. Essentially all the 125I-dIgA in apical culture supernatants was streptavidin precipitable, indicating that dIgA remained bound to antigen during transcytosis. While both dIgA and dIgA ICs bound pIgR with equal affinity (Kd approximately 8 nM), the number of high-affinity binding sites per cell was 2- to 3-fold greater for dIgA than for dIgA ICs. The extent of endocytosis of dIgA and dIgA ICs was correlated with the number of high-affinity binding sites. SDS/PAGE analysis of intracellular dIgA and dIgA ICs demonstrated that in both cases IgA remained undegraded during transport. The results suggest that the pathways of epithelial transcytosis of free dIgA and dIgA ICs are the same. Given the high population density of mucosal IgA plasma cells and the enormous surface area of pIgR-expressing mucosal epithelium, it is likely that significant local transcytosis of IgA ICs occurs in vivo. Such a process would allow direct elimination of IgA ICs at the mucosal sites where they are likely to form, thus providing an important defense function for IgA. Images PMID:1924341

Surface modification of microparticles causes differential uptake responses in normal and tumoral human breast epithelial cells

PubMed Central

Patiño, Tania; Soriano, Jorge; Barrios, Lleonard; Ibáñez, Elena; Nogués, Carme

2015-01-01

The use of micro- and nanodevices as multifunctional systems for biomedical applications has experienced an exponential growth during the past decades. Although a large number of studies have focused on the design and fabrication of new micro- and nanosystems capable of developing multiple functions, a deeper understanding of their interaction with cells is required. In the present study, we evaluated the effect of different microparticle surfaces on their interaction with normal and tumoral human breast epithelial cell lines. For this, AlexaFluor488 IgG functionalized polystyrene microparticles (3 μm) were coated with Polyethyleneimine (PEI) at two different molecular weights, 25 and 750 kDa. The effect of microparticle surface properties on cytotoxicity, cellular uptake and endocytic pathways were assessed for both normal and tumoral cell lines. Results showed a differential response between the two cell lines regarding uptake efficiency and mechanisms of endocytosis, highlighting the potential role of microparticle surface tunning for specific cell targeting. PMID:26068810

Sorting of Marburg Virus Surface Protein and Virus Release Take Place at Opposite Surfaces of Infected Polarized Epithelial Cells

PubMed Central

Sänger, Christian; Mühlberger, Elke; Ryabchikova, Elena; Kolesnikova, Larissa; Klenk, Hans-Dieter; Becker, Stephan

2001-01-01

Marburg virus, a filovirus, causes severe hemorrhagic fever with hitherto poorly understood molecular pathogenesis. We have investigated here the vectorial transport of the surface protein GP of Marburg virus in polarized epithelial cells. To this end, we established an MDCKII cell line that was able to express GP permanently (MDCK-GP). The functional integrity of GP expressed in these cells was analyzed using vesicular stomatitis virus pseudotypes. Further experiments revealed that GP is transported in MDCK-GP cells mainly to the apical membrane and is released exclusively into the culture medium facing the apical membrane. When MDCKII cells were infected with Marburg virus, the majority of GP was also transported to the apical membrane, suggesting that the protein contains an autonomous apical transport signal. Release of infectious progeny virions, however, took place exclusively at the basolateral membrane of the cells. Thus, vectorial budding of Marburg virus is presumably determined by factors other than the surface protein. PMID:11152500

Vocal Fold Surface Hydration: A review

PubMed Central

Leydon, Ciara; Sivasankar, Mahalakshmi; Falciglia, Danielle Lodewyck; Atkins, Christopher; Fisher, Kimberly V.

2009-01-01

Vocal fold surface liquid homeostasis contributes to optimal vocal physiology. In this paper we review emerging evidence that vocal fold surface liquid is maintained in part by salt and water fluxes across the epithelium. Based on recent immunolocalization and electrophysiological findings, we describe a transcellular pathway as one mechanism for regulating superficial vocal fold hydration. We propose that the pathway includes the sodium-potassium pump, sodium-potassium-chloride cotransporter, epithelial sodium channels, cystic fibrosis transmembrane regulator chloride channels, and aquaporin water channels. By integrating knowledge of the regulating mechanisms underlying ion and fluid transport with observations from hydration challenges and treatments using in vitro and in vivo studies, we provide a theoretical basis for understanding how environmental and behavioral challenges and clinical interventions may modify vocal fold surface liquid composition. We present converging evidence that clinical protocols directed at facilitating vocal fold epithelial ion and fluid transport may benefit healthy speakers, those with voice disorders, and those at risk for voice disorders. PMID:19111440

Surface modification of microparticles causes differential uptake responses in normal and tumoral human breast epithelial cells

NASA Astrophysics Data System (ADS)

Patiño, Tania; Soriano, Jorge; Barrios, Lleonard; Ibáñez, Elena; Nogués, Carme

2015-06-01

The use of micro- and nanodevices as multifunctional systems for biomedical applications has experienced an exponential growth during the past decades. Although a large number of studies have focused on the design and fabrication of new micro- and nanosystems capable of developing multiple functions, a deeper understanding of their interaction with cells is required. In the present study, we evaluated the effect of different microparticle surfaces on their interaction with normal and tumoral human breast epithelial cell lines. For this, AlexaFluor488 IgG functionalized polystyrene microparticles (3 μm) were coated with Polyethyleneimine (PEI) at two different molecular weights, 25 and 750 kDa. The effect of microparticle surface properties on cytotoxicity, cellular uptake and endocytic pathways were assessed for both normal and tumoral cell lines. Results showed a differential response between the two cell lines regarding uptake efficiency and mechanisms of endocytosis, highlighting the potential role of microparticle surface tunning for specific cell targeting.

Surface modification of microparticles causes differential uptake responses in normal and tumoral human breast epithelial cells.

PubMed

Patiño, Tania; Soriano, Jorge; Barrios, Lleonard; Ibáñez, Elena; Nogués, Carme

2015-06-12

The use of micro- and nanodevices as multifunctional systems for biomedical applications has experienced an exponential growth during the past decades. Although a large number of studies have focused on the design and fabrication of new micro- and nanosystems capable of developing multiple functions, a deeper understanding of their interaction with cells is required. In the present study, we evaluated the effect of different microparticle surfaces on their interaction with normal and tumoral human breast epithelial cell lines. For this, AlexaFluor488 IgG functionalized polystyrene microparticles (3 μm) were coated with Polyethyleneimine (PEI) at two different molecular weights, 25 and 750 kDa. The effect of microparticle surface properties on cytotoxicity, cellular uptake and endocytic pathways were assessed for both normal and tumoral cell lines. Results showed a differential response between the two cell lines regarding uptake efficiency and mechanisms of endocytosis, highlighting the potential role of microparticle surface tunning for specific cell targeting.

Contributions of ocular surface components to matrix-metalloproteinases (MMP)-2 and MMP-9 in feline tears following corneal epithelial wounding.

PubMed

Petznick, Andrea; Madigan, Michele C; Garrett, Qian; Sweeney, Deborah F; Evans, Margaret D M

2013-01-01

This study investigated ocular surface components that contribute to matrix-metalloproteinase (MMP)-2 and MMP-9 found in tears following corneal epithelial wounding. Laboratory short-haired cats underwent corneal epithelial debridement in one randomly chosen eye (n = 18). Eye-flush tears were collected at baseline and during various healing stages. Procedural control eyes (identical experimental protocol as wounded eyes except for wounding, n = 5) served as controls for tear analysis. MMP activity was analyzed in tears using gelatin zymography. MMP staining patterns were evaluated in ocular tissues using immunohistochemistry and used to determine MMP expression sites responsible for tear-derived MMPs. The proMMP-2 and proMMP-9 activity in tears was highest in wounded and procedural control eyes during epithelial migration (8 to 36 hours post-wounding). Wounded eyes showed significantly higher proMMP-9 in tears only during and after epithelial restratification (day 3 to 4 and day 7 to 28 post-wounding, respectively) as compared to procedural controls (p<0.05). Tears from wounded and procedural control eyes showed no statistical differences for pro-MMP-2 and MMP-9 (p>0.05). Immunohistochemistry showed increased MMP-2 and MMP-9 expression in the cornea during epithelial migration and wound closure. The conjunctival epithelium exhibited highest levels of both MMPs during wound closure, while MMP-9 expression was reduced in conjunctival goblet cells during corneal epithelial migration followed by complete absence of the cells during wound closure. The immunostaining for both MMPs was elevated in the lacrimal gland during corneal healing, with little/no change in the meibomian glands. Conjunctival-associated lymphoid tissue (CALT) showed weak MMP-2 and intense MMP-9 staining. Following wounding, migrating corneal epithelium contributed little to the observed MMP levels in tears. The major sources assessed in the present study for tear-derived MMP-2 and MMP-9 following corneal wounding are the lacrimal gland and CALT. Other sources included stromal keratocytes and conjunctiva with goblet cells.

Apical Plasma Membrane Mispolarization of NaK-ATPase in Polycystic Kidney Disease Epithelia Is Associated with Aberrant Expression of the β2 Isoform

PubMed Central

Wilson, Patricia D.; Devuyst, Olivier; Li, Xiaohong; Gatti, Laura; Falkenstein, Doris; Robinson, Shawn; Fambrough, Douglas; Burrow, Christopher R.

2000-01-01

Autosomal dominant polycystic kidney disease (ADPKD) is a common genetic disease of the kidney, characterized by cystic enlargement of renal tubules, aberrant epithelial proliferation, and ion and fluid secretion into the lumen. Previous studies have shown abnormalities in polarization of membrane proteins, including mislocalization of the NaK-ATPase to the apical plasma membranes of cystic epithelia. Apically located NaK-ATPase has previously been shown to be fully functional in vivo and in membrane-grown ADPKD epithelial cells in vitro, where basal-to-apical 22Na transport was inhibited by application of ouabain to the apical membrane compartment. Studies were conducted with polymerase chain reaction-generated specific riboprobes and polyclonal peptide antibodies against human sequences of α1, α3, β1, and β2 subunits of NaK-ATPase. High levels of expression of α1 and β1 messenger RNA were detected in ADPKD and age-matched normal adult kidneys in vivo, whereas β2 messenger RNA was detected only in ADPKD kidneys. Western blot analysis and immunocytochemical studies showed that, in normal adult kidneys, peptide subunit-specific antibodies against α1 and β1 localized to the basolateral membranes of normal renal tubules, predominantly thick ascending limbs of Henle’s loop. In ADPKD kidneys, α1 and β2 subunits were localized to the apical epithelial cell membranes, whereas β1 was distributed throughout the cytoplasm and predominantly in the endoplasmic reticulum, but was not seen associated with cystic epithelial cell membranes or in cell membrane fractions. Polarizing, renal-derived epithelial Madin Darby canine kidney cells, stably expressing normal or N-terminally truncated chicken β1 subunits, showed selective accumulation in the basolateral Madin Darby canine kidney cell surface, whereas c-myc epitope-tagged chicken β2 or human β2 subunits accumulated selectively in the apical cell surface. Similarly, human ADPKD epithelial cell lines, which endogenously expressed α1 and β2 NaK-ATPase subunits, showed colocalization at the apical cell surface and coassociation by immunoprecipitation analysis. These results are consistent with a model in which the additional transcription and translation of the β2 subunit of NaK-ATPase may result in the apical mislocalization of NaK-ATPase in ADPKD cystic epithelia. PMID:10623674

Comparison of the effects of the CO2 laser and chlorohexidine on the decontamination of infected cutaneous wounds: a histologic study in rats.

PubMed

Pinheiro, Antonio Luiz B; Cavalcanti Das Neves, Jérläcia; Lisboa De Castro, Jurema Freire; Lima Verde Santos, José Zilton; Da Fonseca Ribeiro De Sena, Kêsia Xisto; Brugnera, Aldo; Zanin, Fátima A; Matos De Oliveira, Marcos André

2002-06-01

The aim of this study was to compare histologically the effects of CO2 laser and chlorohexidine gluconate (4%) on Staphylococcus aureus-infected cutaneous wounds. Wound infection constitutes a big risk for patients, and it is usually associated with increased morbidity, mortality and hospital costs. It is accepted that local treatment of these infections is effective. Standardized wounds created on the dorsum of 36 rats were infected with Staphylococcus aureus and treated during 6 days as follows: group I, chlorohexidine gluconate (4%) applied to the wound surface during 1 min during 6 days; group II, single CO2 laser irradiation (8 W, CW, unfocused, 8-cm focal distance, 81,530 W/cm(2)), maintaining surface debris; group III, single CO2 laser irradiation (8 W, CW, unfocused, 8-cm focal distance, 81,530 W/cm(2)), removing the surface debris. Seven days after wounding, the animals were killed and specimens taken for light microscopy. On control wounds, epithelial ulceration and neutrophylic and lymphoplasmocitary inflammatory infiltrate was observed. On group II, there was epithelial hyperplasia, areas of ulceration and intense neutrophylic and lymphoplasmocitary inflammatory infiltrate. In group III, there was a neutrophylic inflammatory infiltrate underneath the surface debris and below that intense lymphoplasmocitary inflammatory infiltrate. When the surface debris was removed (group IV), there was epithelial ulceration and mild lymphoplasmocitary inflammatory infiltrate and fibroblasts and collagen fibers. The results of this study show that infected wounds treated with 4% chlorohexidine show a more pronounced inflammatory reaction when compared to that observed when the CO2 laser is used, especially when surface debris are removed; surface debris removal on laser-treated wounds results in better and more rapid healing; the surface debris may act as a culture medium for bacterial growth or, because of its characteristics, it may act as a local irritant and delay healing.

Silk film biomaterials for ocular surface repair

NASA Astrophysics Data System (ADS)

Lawrence, Brian David

Current biomaterial approaches for repairing the cornea's ocular surface upon injury are partially effective due to inherent material limitations. As a result there is a need to expand the biomaterial options available for use in the eye, which in turn will help to expand new clinical innovations and technology development. The studies illustrated here are a collection of work to further characterize silk film biomaterials for use on the ocular surface. Silk films were produced from regenerated fibroin protein solution derived from the Bombyx mori silkworm cocoon. Methods of silk film processing and production were developed to produce consistent biomaterials for in vitro and in vivo evaluation. A wide range of experiments was undertaken that spanned from in vitro silk film material characterization to in vivo evaluation. It was found that a variety of silk film properties could be controlled through a water-annealing process. Silk films were then generated that could be use in vitro to produce stratified corneal epithelial cell sheets comparable to tissue grown on the clinical standard substrate of amniotic membrane. This understanding was translated to produce a silk film design that enhanced corneal healing in vivo on a rabbit injury model. Further work produced silk films with varying surface topographies that were used as a simplified analog to the corneal basement membrane surface in vitro. These studies demonstrated that silk film surface topography is capable of directing corneal epithelial cell attachment, growth, and migration response. Most notably epithelial tissue development was controllably directed by the presence of the silk surface topography through increasing cell sheet migration efficiency at the individual cellular level. Taken together, the presented findings represent a comprehensive characterization of silk film biomaterials for use in ocular surface reconstruction, and indicate their utility as a potential material choice in the development of innovative procedures and technologies for corneal repair.

Enhanced vaginal drug delivery through the use of hypotonic formulations that induce fluid uptake

PubMed Central

Ensign, Laura M.; Hoen, Timothy; Maisel, Katharina; Cone, Richard; Hanes, Justin

2013-01-01

Mucosal epithelia use osmotic gradients for fluid absorption and secretion. We hypothesized that administration of hypotonic solutions would induce fluid uptake that could be advantageous for rapidly delivering drugs through mucus to the vaginal epithelium. We found that hypotonic formulations markedly increased the rate at which small molecule drugs and muco-inert nanoparticles (mucus-penetrating particles, or MPP), but not conventional mucoadhesive nanparticles (CP), reached the vaginal epithelial surface in vivo in mice. Additionally, hypotonic formulations greatly enhanced drug and MPP delivery to the entire epithelial surface, including deep into the vaginal folds (rugae) that drugs or MPP in isotonic formulations failed to reach efficiently. However, hypotonic formulations caused unencapsulated “free” drugs to be drawn through the epithelium, reducing vaginal retention. In contrast, hypotonic formulations caused MPP to accumulate rapidly and uniformly on vaginal surfaces, ideally positioned for localized sustained drug delivery. Using a mouse model of vaginal genital herpes (HSV-2) infection, we found that hypotonic delivery of free drug led to improved immediate protection, but diminished longer-term protection. In contrast, as we previously demonstrated, hypotonic delivery of drug via MPP led to better long-term retention and protection in the vagina. Importantly, we demonstrate that slightly hypotonic formulations provided rapid and uniform delivery of MPP to the entire vaginal surface, thus enabling formulations with minimal risk of epithelial toxicity. Hypotonic formulations for vaginal drug delivery via MPP may significantly improve prevention and treatment of reproductive tract diseases and disorders. PMID:23769419

Embryonic wound healing by apical contraction and ingression in Xenopus laevis.

PubMed

Davidson, Lance A; Ezin, Akouavi M; Keller, Ray

2002-11-01

We have characterized excisional wounds in the animal cap of early embryos of the frog Xenopus laevis and found that these wounds close accompanied by three distinct processes: (1) the assembly of an actin purse-string in the epithelial cells at the wound margin, (2) contraction and ingression of exposed deep cells, and (3) protrusive activity of epithelial cells at the margin. Microsurgical manipulation allowing fine control over the area and depth of the wound combined with videomicroscopy and confocal analysis enabled us to describe the kinematics and challenge the mechanics of the closing wound. Full closure typically occurs only when the deep, mesenchymal cell-layer of the ectoderm is left intact; in contrast, when deep cells are removed along with the superficial, epithelial cell-layer of the ectoderm, wounds do not close. Actin localizes to the superficial epithelial cell-layer at the wound margin immediately after wounding and forms a contiguous "purse-string" in those cells within 15 min. However, manipulation and closure kinematics of shaped wounds and microsurgical cuts made through the purse-string rule out a major force-generating role for the purse-string. Further analysis of the cell behaviors within the wound show that deep, mesenchymal cells contract their apical surfaces and ingress from the exposed surface. High resolution time-lapse sequences of cells at the leading edge of the wound show that these cells undergo protrusive activity only during the final phases of wound closure as the ectoderm reseals. We propose that assembly of the actin purse-string works to organize and maintain the epithelial sheet at the wound margin, that contraction and ingression of deep cells pulls the wound margins together, and that protrusive activity of epithelial cells at the wound margin reseals the ectoderm and re-establishes tissue integrity during wound healing in the Xenopus embryonic ectoderm. Copyright 2002 Wiley-Liss, Inc.

A pharmacological modification of pain and epithelial healing in contemporary transepithelial all-surface laser ablation (ASLA).

PubMed

Aslanides, Ioannis M; Selimis, Vasilis D; Bessis, Nikolaos V; Georgoudis, Panagiotis N

2015-01-01

We report our experience with the use of the matrix regenerating agent (RGTA) Cacicol(®) after reverse transepithelial all-surface laser ablation (ASLA)-SCHWIND to assess the safety, efficacy, pain, and epithelial healing. Forty eyes of 20 myopic patients were prospectively recruited to a randomized fellow eye study. Patients underwent transepithelial ASLA in both eyes, with one of the eyes randomly assigned to the use of the RGTA Cacicol. Postoperative pain and vision were subjectively assessed with the use of a questionnaire on the operative day, at 24 hours, 48 hours and 72 hours. Epithelial defect area size was measured at 24 hours, 48 hours, and 72 hours. Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were assessed at 1 month. Mean UDVA at 1 month was LogMAR 0.028. The epithelial defect area was 10.91 mm(2) and 13.28 mm(2) at 24 hours and 1.39 mm(2) and 1.24 mm(2) at 48 hours for treated and nontreated eyes, respectively. Overall, 50% and 65% of treated and nontreated eyes healed by 48 hours. There was no statistically significant difference in the subjective vision between the groups, although vision of patients in the RGTA group was reported to be better. Pain scores were better at 24 hours and 48 hours in the RGTA group but with no statistically significant difference. The use of RGTA Cacicol shows faster epithelial recovery after transepithelial ASLA for myopia. Subjectively reported scores of pain and subjective vision were better in the RGTA group, although the difference was not statistically significant. There seems to be a consensual acceleration of epithelial healing even in eyes that did not receive treatment. There were no adverse events and no incidents of inflammation, delayed healing, or haze.

A pharmacological modification of pain and epithelial healing in contemporary transepithelial all-surface laser ablation (ASLA)

PubMed Central

Aslanides, Ioannis M; Selimis, Vasilis D; Bessis, Nikolaos V; Georgoudis, Panagiotis N

2015-01-01

Purpose We report our experience with the use of the matrix regenerating agent (RGTA) Cacicol® after reverse transepithelial all-surface laser ablation (ASLA)-SCHWIND to assess the safety, efficacy, pain, and epithelial healing. Methods Forty eyes of 20 myopic patients were prospectively recruited to a randomized fellow eye study. Patients underwent transepithelial ASLA in both eyes, with one of the eyes randomly assigned to the use of the RGTA Cacicol. Postoperative pain and vision were subjectively assessed with the use of a questionnaire on the operative day, at 24 hours, 48 hours and 72 hours. Epithelial defect area size was measured at 24 hours, 48 hours, and 72 hours. Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were assessed at 1 month. Results Mean UDVA at 1 month was LogMAR 0.028. The epithelial defect area was 10.91 mm2 and 13.28 mm2 at 24 hours and 1.39 mm2 and 1.24 mm2 at 48 hours for treated and nontreated eyes, respectively. Overall, 50% and 65% of treated and nontreated eyes healed by 48 hours. There was no statistically significant difference in the subjective vision between the groups, although vision of patients in the RGTA group was reported to be better. Pain scores were better at 24 hours and 48 hours in the RGTA group but with no statistically significant difference. Conclusion The use of RGTA Cacicol shows faster epithelial recovery after transepithelial ASLA for myopia. Subjectively reported scores of pain and subjective vision were better in the RGTA group, although the difference was not statistically significant. There seems to be a consensual acceleration of epithelial healing even in eyes that did not receive treatment. There were no adverse events and no incidents of inflammation, delayed healing, or haze. PMID:25931809

Pathophysiology of ocular surface squamous neoplasia

PubMed Central

Gichuhi, Stephen; Ohnuma, Shin-ichi; Sagoo, Mandeep S.; Burton, Matthew J.

2014-01-01

The incidence of ocular surface squamous neoplasia (OSSN) is strongly associated with solar ultraviolet (UV) radiation, HIV and human papilloma virus (HPV). Africa has the highest incidence rates in the world. Most lesions occur at the limbus within the interpalpebral fissure particularly the nasal sector. The nasal limbus receives the highest intensity of sunlight. Limbal epithelial crypts are concentrated nasally and contain niches of limbal epithelial stem cells in the basal layer. It is possible that these are the progenitor cells in OSSN. OSSN arises in the basal epithelial cells spreading towards the surface which resembles the movement of corneo-limbal stem cell progeny before it later invades through the basement membrane below. UV radiation damages DNA producing pyrimidine dimers in the DNA chain. Specific CC → TT base pair dimer transformations of the p53 tumour-suppressor gene occur in OSSN allowing cells with damaged DNA past the G1-S cell cycle checkpoint. UV radiation also causes local and systemic photoimmunosuppression and reactivates latent viruses such as HPV. The E7 proteins of HPV promote proliferation of infected epithelial cells via the retinoblastoma gene while E6 proteins prevent the p53 tumour suppressor gene from effecting cell-cycle arrest of DNA-damaged and infected cells. Immunosuppression from UV radiation, HIV and vitamin A deficiency impairs tumour immune surveillance allowing survival of aberrant cells. Tumour growth and metastases are enhanced by; telomerase reactivation which increases the number of cell divisions a cell can undergo; vascular endothelial growth factor for angiogenesis and matrix metalloproteinases (MMPs) that destroy the intercellular matrix between cells. Despite these potential triggers, the disease is usually unilateral. It is unclear how HPV reaches the conjunctiva. PMID:25447808

Confocal microscopy of epithelial and langerhans cells of the cornea in patients using travoprost drops containing two different preservatives.

PubMed

Marsovszky, László; Resch, Miklós D; Visontai, Zsuzsanna; Németh, János

2014-07-01

The recently developed confocal cornea microscopy offers the opportunity to examine pathologies of the cornea and to gain insight into the activity of innate immunity. We aimed to investigate the corneal epithelial and Langerhans cell (LC) densities along with dry eye parameters in primary open-angle glaucoma (POAG) subjects, treated with either of two commercially available travoprost 0.004 % topical medications containing different preservatives. (1: benzalkonium chloride 0.015 % (TravBAK) and 2: polyquaternium-1 (PQ) 0.001 % (TravPQ). Consecutive case series of nineteen POAG patients on TravBAK (mean age: 64.8 ± 13.6 years), nineteen POAG patients on TravPQ (mean age: 66.8 ± 11.3 years) and nineteen age-matched healthy control subjects (63.8 ± 8.2 years). Ocular surface disease index (OSDI), lid parallel conjunctival folds (LIPCOF), Schirmer test (ST) and tear break up time (TBUT) were assessed, and then corneal epithelial and LC densities were investigated with confocal microscopy. Tear production was significantly reduced in both glaucoma patient groups compared to healthy individuals (p < 0.05). TBUT was significantly reduced and epithelial cell densities were significantly greater in patients treated with TravBAK compared to healthy individuals (p < 0.05 for all). LC densities were greater in both glaucoma groups compared to control subjects (p < 0.05 for all). Travoprost therapy may compromise ocular surface. The limited alertness of the corneal immune system found in patients with TravPQ can be considered as indicators of a less disturbed ocular surface and better controlled corneal homeostasis.

Comparison of Topical Application of TSG-6, Cyclosporine, and Prednisolone for Treating Dry Eye.

PubMed

Kim, Yu Jeong; Ryu, Jin Suk; Park, Se Yeon; Lee, Hyun Ju; Ko, Jung Hwa; Kim, Mee Kum; Wee, Won Ryang; Oh, Joo Youn

2016-04-01

To compare the therapeutic effects of topical tumor necrosis factor (TNF)-α-stimulated gene/protein-6 (TSG-6) with those of cyclosporine and prednisolone eye drops in NOD.B10.H2 mice, a model for inflammation-mediated dry eye. The 12-week-old NOD.B10.H2 mice were topically administered recombinant TSG-6 (0.1%) 4 times a day, 0.05% cyclosporine (Restasis) twice a day, or 1% prednisolone (Pred Forte) 4 times a day for 1 week. Aqueous tear production was measured by phenol red thread test, and corneal epithelial damage was observed with lissamine green and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Conjunctival goblet cell number was evaluated with periodic acid-Schiff staining. The levels of inflammatory cytokines were analyzed in the ocular surface (cornea and conjunctiva) and intraorbital gland. The dose-dependent effects of topical TSG-6 (0.001, 0.01, and 0.1%) were tested. Tear production and goblet cell density were significantly increased in all groups receiving TSG-6, cyclosporine, and prednisolone. Corneal epithelial staining was markedly reduced by TSG-6 and cyclosporine but not by prednisolone. In prednisolone-treated eyes, corneal epithelial thickness was decreased, and apoptosis of corneal epithelial cells was increased. The levels of interferon gamma and TNF-α in the ocular surface and intraorbital gland were significantly repressed by TSG-6 and cyclosporine, and prednisolone treatment significantly reduced the level of interferon gamma. The effects of TSG-6 on the ocular surface and tear production were dose dependent. Topical TSG-6 was as effective in inflammation-mediated dry eye as cyclosporine eye drops. Topical prednisolone suppressed inflammation but induced apoptosis in the corneal epithelium.

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

PubMed

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

2014-01-01

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

Ursodeoxycholic acid attenuates colonic epithelial secretory function

PubMed Central

Kelly, Orlaith B; Mroz, Magdalena S; Ward, Joseph B J; Colliva, Carolina; Scharl, Michael; Pellicciari, Roberto; Gilmer, John F; Fallon, Padraic G; Hofmann, Alan F; Roda, Aldo; Murray, Frank E; Keely, Stephen J

2013-01-01

Dihydroxy bile acids, such as chenodeoxycholic acid (CDCA), are well known to promote colonic fluid and electrolyte secretion, thereby causing diarrhoea associated with bile acid malabsorption. However, CDCA is rapidly metabolised by colonic bacteria to ursodeoxycholic acid (UDCA), the effects of which on epithelial transport are poorly characterised. Here, we investigated the role of UDCA in the regulation of colonic epithelial secretion. Cl− secretion was measured across voltage-clamped monolayers of T84 cells and muscle-stripped sections of mouse or human colon. Cell surface biotinylation was used to assess abundance/surface expression of transport proteins. Acute (15 min) treatment of T84 cells with bilateral UDCA attenuated Cl− secretory responses to the Ca2+ and cAMP-dependent secretagogues carbachol (CCh) and forskolin (FSK) to 14.0 ± 3.8 and 40.2 ± 7.4% of controls, respectively (n= 18, P < 0.001). Investigation of the molecular targets involved revealed that UDCA acts by inhibiting Na+/K+-ATPase activity and basolateral K+ channel currents, without altering their cell surface expression. In contrast, intraperitoneal administration of UDCA (25 mg kg−1) to mice enhanced agonist-induced colonic secretory responses, an effect we hypothesised to be due to bacterial metabolism of UDCA to lithocholic acid (LCA). Accordingly, LCA (50–200 μm) enhanced agonist-induced secretory responses in vitro and a metabolically stable UDCA analogue, 6α-methyl-UDCA, exerted anti-secretory actions in vitro and in vivo. In conclusion, UDCA exerts direct anti-secretory actions on colonic epithelial cells and metabolically stable derivatives of the bile acid may offer a new approach for treating intestinal diseases associated with diarrhoea. PMID:23507881

Intestinal epithelial TOLLerance versus inTOLLerance of commensals.

PubMed

Cario, Elke; Podolsky, Daniel K

2005-05-01

This brief review summarizes the current understanding of Toll-like receptor (TLRs) mediated intestinal epithelial mechanisms of commensal tolerance versus intolerance and provides an update on the downstream negative control of signaling responses through decreased surface expression, interregulation with NOD2, overexpression of Tollip, various inhibitors of NF-kappaB as well as soluble tolerizing mediators present in lumen and serum which all may maintain or--when dysregulated--impair mucosal homeostasis in health or disease, respectively.

Multi-Drug Resistance Transporter 2 Regulates Mucosal Inflammation by Facilitating the Synthesis of Hepoxilin A3

PubMed Central

Pazos, Michael; Siccardi, Dario; Mumy, Karen L.; Bien, Jeffrey D.; Louie, Steve; Shi, Hai Ning; Gronert, Karsten; Mrsny, Randall J.; McCormick, Beth A.

2008-01-01

Neutrophil transmigration across mucosal surfaces contributes to dysfunction of epithelial barrier properties, a characteristic underlying many mucosal inflammatory diseases. Thus, insight into the directional movement of neutrophils across epithelial barriers will provide important information relating to the mechanisms of such inflammatory disorders. The eicosanoid hepoxilin A3, an endogenous product of 12-lipoxygenase activity, is secreted from the apical surface of the epithelial barrier and establishes a chemotatic gradient to guide neutrophils from the submucosa, across epithelia to the luminal site of an inflammatory stimulus - the final step in neutrophil recruitment. Currently, little is known regarding how hepoxilin A3 is secreted from the intestinal epithelium during an inflammatory insult. In this study we reveal that hepoxilin A3 is a substrate for the apical efflux ABC transporter, multi-drug resistance protein 2 (MRP2). Moreover, using multiple in vitro and in vivo models we show that induction of intestinal inflammation profoundly up-regulates apical expression of MRP2, and that interfering with hepoxilin A3 synthesis and/or inhibition of MRP2 function results in a marked reduction in inflammation and severity of disease. Lastly, examination of inflamed intestinal epithelia in human biopsies revealed up-regulation of MRP2. Thus, blocking hepoxilin A3 synthesis and/or inhibiting MRP2 may lead to the development of new therapeutic strategies for the treatment of epithelial-associated inflammatory conditions. PMID:19017997

Modeling the Epithelial Morphogenesis of Germ Band Retraction in Three Dimensions

NASA Astrophysics Data System (ADS)

McCleery, W. Tyler; Veldhuis, Jim; Brodland, G. Wayne; Crews, Sarah M.; Hutson, M. Shane

2015-03-01

Embryogenesis of higher-order organisms is driven by an intricate coordination of cellular mechanics. Mechanical analysis of certain developmental events, e.g., dorsal closure in the fruit fly D. melanogaster, has been sufficiently described using two-dimensional models. Here, we present a three-dimensional modeling technique to investigate germ band retraction (GBR) - a whole-embryo, irreducibly 3D morphogenetic event. At the start of GBR, the epithelial tissue known as the germ band is initially wrapped around the posterior end of an ellipsoidal fly embryo. This tissue then retracts as an adjacent epithelial tissue, the amnioserosa, simultaneously contracts. We hypothesize that proper GBR requires maintenance of cell-cell connectivity in the amnioserosa, as well as both cell and tissue topology on the embryo's ellipsoidal surface. The exact interfacial tensions are less important. We test the dynamic interactions between these two tissues on a 3D ellipsoidal last. To speed simulation run times and focus on the relevant tissues, epithelial cells are defined as polygons constrained to lie on the surface of the ellipsoidal last. These cells have adjustable parameters such as edge tensions and cell pressures. Tissue movements are simulated by balancing these dynamic cell-level forces with viscous resistance and allowing cells to exchange neighbors. This modeling approach helps elucidate the multicellular stress fields in normal and aberrant development, providing deeper insight into the mechanical interdependence of developing tissues.

Rescue of CF airway epithelial cell function in vitro by a CFTR potentiator, VX-770

PubMed Central

Van Goor, Fredrick; Hadida, Sabine; Grootenhuis, Peter D. J.; Burton, Bill; Cao, Dong; Neuberger, Tim; Turnbull, Amanda; Singh, Ashvani; Joubran, John; Hazlewood, Anna; Zhou, Jinglan; McCartney, Jason; Arumugam, Vijayalaksmi; Decker, Caroline; Yang, Jennifer; Young, Chris; Olson, Eric R.; Wine, Jeffery J.; Frizzell, Raymond A.; Ashlock, Melissa; Negulescu, Paul

2009-01-01

Cystic fibrosis (CF) is a fatal genetic disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR), a protein kinase A (PKA)-activated epithelial anion channel involved in salt and fluid transport in multiple organs, including the lung. Most CF mutations either reduce the number of CFTR channels at the cell surface (e.g., synthesis or processing mutations) or impair channel function (e.g., gating or conductance mutations) or both. There are currently no approved therapies that target CFTR. Here we describe the in vitro pharmacology of VX-770, an orally bioavailable CFTR potentiator in clinical development for the treatment of CF. In recombinant cells VX-770 increased CFTR channel open probability (Po) in both the F508del processing mutation and the G551D gating mutation. VX-770 also increased Cl− secretion in cultured human CF bronchial epithelia (HBE) carrying the G551D gating mutation on one allele and the F508del processing mutation on the other allele by ≈10-fold, to ≈50% of that observed in HBE isolated from individuals without CF. Furthermore, VX-770 reduced excessive Na+ and fluid absorption to prevent dehydration of the apical surface and increased cilia beating in these epithelial cultures. These results support the hypothesis that pharmacological agents that restore or increase CFTR function can rescue epithelial cell function in human CF airway. PMID:19846789

Nanotechnology for the detection and kill of circulating tumor cells

NASA Astrophysics Data System (ADS)

Gao, Yang; Yuan, Zhou

2014-09-01

Circulating tumor cells (CTCs) represent a surrogate biomarker of hematogenous metastases and thus could be considered as a `liquid biopsy' which reveals metastasis in action. But it is absolutely a challenge to detect CTCs due to their extreme rarity. At present, the most common principle is to take advantage of the epithelial surface markers of CTCs which attach to a specific antibody. Antibody-magnetic nanobeads combine with the epithelial surface markers, and then the compound is processed by washing, separation, and detection. However, a proportion of CTC antigen expressions are down-regulated or lost in the process of epithelial-mesenchymal transition (EMT), and thus, this part of CTCs cannot be detected by classical detection methods such as CellSearch. To resolve this problem, some multiple-marker CTC detections have been developed rapidly. Additionally, nanotechnology is a promising approach to kill CTCs with high efficiency. Implantable nanotubes coated with apoptosis-promoting molecules improve the disease-free survival and overall survival. The review introduces some novel CTC detection techniques and therapeutic methods by virtue of nanotechnology to provide a better knowledge of the progress about CTC study.

Integrins beta 5, beta 3 and alpha v are apically distributed in endometrial epithelium.

PubMed

Aplin, J D; Spanswick, C; Behzad, F; Kimber, S J; Vićovac, L

1996-07-01

Several adhesion molecules have been shown to occur at the surface of endometrial cells. One of these is the integrin alpha v subunit which associates with various beta chains including beta 5. We demonstrate the presence of integrin beta 5 polypeptide in human endometrial epithelial cells throughout the menstrual cycle using immunocytochemistry with monospecific antibodies, and at the mRNA level by thermal amplification from endometrial cDNA. Integrin beta 5 is also found in a population of bone marrow-derived cells. A notable feature of the distribution of the beta 5 subunit in the glandular and luminal epithelium is its apical localization, which may suggest an involvement in implantation. However, no evidence was found for regulated expression of epithelial beta 5. In mouse, the beta 5 subunit is found at both the apical and basal surface of epithelial cells and expression is essentially oestrous cycle-independent. Comparisons are made in both species with the distribution of the alpha v and beta 3 subunits which also localize to the apical epithelium.

Breast Cancer Research at NASA

NASA Technical Reports Server (NTRS)

1998-01-01

Epithelial and fibroblast cell coculture: Long-term growth human mammary epithelial cells (HMEC) admixed in coculture with fibroblast from the same initial breast tissue grown as 3-dimenstional constructions in the presence of attachment beads in the NASA Bioreactor. A: A typical constrct about 2.0 mm in diameter without beads on the surface. The center of these constrcts is hollow, and beads are organized about the irner surface. Although the coculture provides smaller constructs than the monoculture, the metabolic of the organized cells is about the same. B, C, D: Closer views of cells showing that the shape of cells and cell-to-cell interactions apprear different in the coculture than in the monoculture constructs. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

Synaptotagmin-Like Proteins Control Formation of a Single Apical Membrane Domain in Epithelial Cells

PubMed Central

Gálvez-Santisteban, Manuel; Rodriguez-Fraticelli, Alejo E.; Bryant, David M.; Vergarajauregui, Silvia; Yasuda, Takao; Bañón-Rodríguez, Inmaculada; Bernascone, Ilenia; Datta, Anirban; Spivak, Natalie; Young, Kitty; Slim, Christiaan L.; Brakeman, Paul R.; Fukuda, Mitsunori; Mostov, Keith E.; Martín-Belmonte, Fernando

2012-01-01

SUMMARY The formation of epithelial tissues requires both the generation of apical-basal polarity and the co-ordination of this polarity between neighboring cells to form a central lumen. During de novo lumen formation, vectorial membrane transport contributes to formation of a singular apical membrane, resulting in contribution of each cell to only a single lumen. Here, from a functional screen for genes required for 3D epithelial architecture we identify key roles for Synaptotagmin-like proteins 2-a and 4-a (Slp2-a/4-a) in generation of a single apical surface per cell. Slp2-a localizes to the luminal membrane in a PI(4,5)P2-dependent manner, where it targets Rab27-loaded vesicles to initiate a single lumen. Vesicle tethering and fusion is controlled by Slp4-a, in conjunction with Rab27/Rab3/Rab8 and the SNARE Syntaxin-3. Together, Slp2-a/4-a co-ordinate the spatiotemporal organization of vectorial apical transport to ensure only a single apical surface, and thus formation of a single lumen, occurs per cell. PMID:22820376

Microgravity

NASA Image and Video Library

1998-10-10

Epithelial and fibroblast cell coculture: Long-term growth human mammary epithelial cells (HMEC) admixed in coculture with fibroblast from the same initial breast tissue grown as 3-dimenstional constructions in the presence of attachment beads in the NASA Bioreactor. A: A typical constrct about 2.0 mm in diameter without beads on the surface. The center of these constrcts is hollow, and beads are organized about the irner surface. Although the coculture provides smaller constructs than the monoculture, the metabolic of the organized cells is about the same. B, C, D: Closer views of cells showing that the shape of cells and cell-to-cell interactions apprear different in the coculture than in the monoculture constructs. NASA's Marshall Space Flight Center (MSFC) is sponsoring research with Bioreactors, rotating wall vessels designed to grow tissue samples in space, to understand how breast cancer works. This ground-based work studies the growth and assembly of human mammary epithelial cell (HMEC) from breast cancer susceptible tissue. Radiation can make the cells cancerous, thus allowing better comparisons of healthy vs. tunorous tissue. Credit: Dr. Robert Richmond, NASA/Marshall Space Flight Center (MSFC).

A Nasal Epithelial Receptor for Staphylococcus aureus WTA Governs Adhesion to Epithelial Cells and Modulates Nasal Colonization

PubMed Central

Faulstich, Manuela; Grau, Timo; Severin, Yannik; Unger, Clemens; Hoffmann, Wolfgang H.; Rudel, Thomas; Autenrieth, Ingo B.; Weidenmaier, Christopher

2014-01-01

Nasal colonization is a major risk factor for S. aureus infections. The mechanisms responsible for colonization are still not well understood and involve several factors on the host and the bacterial side. One key factor is the cell wall teichoic acid (WTA) of S. aureus, which governs direct interactions with nasal epithelial surfaces. We report here the first receptor for the cell wall glycopolymer WTA on nasal epithelial cells. In several assay systems this type F-scavenger receptor, termed SREC-I, bound WTA in a charge dependent manner and mediated adhesion to nasal epithelial cells in vitro. The impact of WTA and SREC-I interaction on epithelial adhesion was especially pronounced under shear stress, which resembles the conditions found in the nasal cavity. Most importantly, we demonstrate here a key role of the WTA-receptor interaction in a cotton rat model of nasal colonization. When we inhibited WTA mediated adhesion with a SREC-I antibody, nasal colonization in the animal model was strongly reduced at the early onset of colonization. More importantly, colonization stayed low over an extended period of 6 days. Therefore we propose targeting of this glycopolymer-receptor interaction as a novel strategy to prevent or control S. aureus nasal colonization. PMID:24788600

Neisseria gonorrhoeae breaches the apical junction of polarized epithelial cells for transmigration by activating EGFR

PubMed Central

Edwards, Vonetta L.; Wang, Liang-Chun; Dawson, Valerie; Stein, Daniel C.; Song, Wenxia

2017-01-01

Summary Neisseria gonorrhoeae initiates infection at the apical surface of columnar endocervical epithelial cells in the female reproductive tract. These cells provide a physical barrier against pathogens by forming continuous apical junctional complexes between neighbouring cells. This study examines the interaction of gonococci (GC) with polarized epithelial cells. We show that viable GC preferentially localize at the apical side of the cell–cell junction in polarized endometrial and colonic epithelial cells, HEC-1-B and T84. In GC-infected cells, continuous apical junctional complexes are disrupted, and the junction-associated protein β-catenin is redistributed from the apical junction to the cytoplasm and to GC adherent sites; however, overall cellular levels remain unchanged. This redistribution of junctional proteins is associated with a decrease in the ‘fence’ function of the apical junction but not its ‘gate’ function. Disruption of the apical junction by removing calcium increases GC transmigration across the epithelial monolayer. GC inoculation induces the phosphorylation of both epidermal growth factor receptor (EGFR) and β-catenin, while inhibition of EGFR kinase activity significantly reduces both GC-induced β-catenin redistribution and GC transmigration. Therefore, the gonococcus is capable of weakening the apical junction and polarity of epithelial cells by activating EGFR, which facilitates GC transmigration across the epithelium. PMID:23279089

Control of apico-basal epithelial polarity by the microtubule minus-end-binding protein CAMSAP3 and spectraplakin ACF7.

PubMed

Noordstra, Ivar; Liu, Qingyang; Nijenhuis, Wilco; Hua, Shasha; Jiang, Kai; Baars, Matthijs; Remmelzwaal, Sanne; Martin, Maud; Kapitein, Lukas C; Akhmanova, Anna

2016-11-15

The microtubule cytoskeleton regulates cell polarity by spatially organizing membrane trafficking and signaling processes. In epithelial cells, microtubules form parallel arrays aligned along the apico-basal axis, and recent work has demonstrated that the members of CAMSAP/Patronin family control apical tethering of microtubule minus ends. Here, we show that in mammalian intestinal epithelial cells, the spectraplakin ACF7 (also known as MACF1) specifically binds to CAMSAP3 and is required for the apical localization of CAMSAP3-decorated microtubule minus ends. Loss of ACF7 but not of CAMSAP3 or its homolog CAMSAP2 affected the formation of polarized epithelial cysts in three-dimensional cultures. In short-term epithelial polarization assays, knockout of CAMSAP3, but not of CAMSAP2, caused microtubule re-organization into a more radial centrosomal array, redistribution of Rab11-positive (also known as Rab11A) endosomes from the apical cell surface to the pericentrosomal region and inhibition of actin brush border formation at the apical side of the cell. We conclude that ACF7 is an important regulator of apico-basal polarity in mammalian intestinal cells and that a radial centrosome-centered microtubule organization can act as an inhibitor of epithelial polarity. © 2016. Published by The Company of Biologists Ltd.

Impact of Satellite Atmospheric Motion Vectors In the GMAO GEOS-5 Global Data Assimilation System

NASA Technical Reports Server (NTRS)

Gelaro, Ronald; Merkova, Dagmar

2012-01-01

The WMO and THORPEX co-sponsored fifth Workshop on the Impact of Various Observing Systems on Numerical Weather Prediction will be organized by the Expert Team on the Evolution of the Global Observing System in Sedona, Arizona, United States, from 22 to 25 May 2012. Participants are expected to come from all the major NWP centres which are active in the area of impact studies. The workshop will be conducted in English. As for the first four workshops it is planned to produce a workshop report to be published as a WMO Technical Report that will include the papers submitted by the participants. The previous four workshops in this series took place in Geneva {April 1997), Toulouse (March 2000), Alpbach (March 2004) and Geneva (May 2008). Results from Observing System Experiments (OSEs), both with global and regional aspects were presented and conclusions were drawn concerning the contributions of the various components of the observing system to the large scale forecast skill at short and medium range (Workshop Proceedings were published as WMO World Weather Watch Technical Reports TD No. 868, 1034, 1228 and 1450). Since then, some significant changes and developments have affected the global observing system and more efforts have been devoted to meso-scale observing and assimilation systems. There has also been a trend toward using techniques other than OSEs to document data impact, such as adjoint-based sensitivity to observations or ensemble-based sensitivity. Field experiments have been carried out, in particular through the THORPEX project, and the use of targeted data has been assessed.

Human fetal enterocytes in vitro: modulation of the phenotype by extracellular matrix.

PubMed Central

Sanderson, I R; Ezzell, R M; Kedinger, M; Erlanger, M; Xu, Z X; Pringault, E; Leon-Robine, S; Louvard, D; Walker, W A

1996-01-01

The differentiation of small intestinal epithelial cells may require stimulation by microenvironmental factors in vivo. In this study, the effects of mesenchymal and luminal elements in nonmalignant epithelia] cells isolated from the human fetus were studied in vitro. Enterocytes from the human fetus were cultured and microenvironmental factors were added in stages, each stage more closely approximating the microenvironment in vivo. Four stages were examined: epithelial cells derived on plastic from intestinal culture and grown as a cell clone, the same cells grown on connective tissue support, primary epithelial explants grown on fibroblasts with a laminin base, and primary epithelial explants grown on fibroblasts and laminin with n-butyrate added to the incubation medium. The epithelial cell clone dedifferentiated when grown on plastic; however, the cells expressed cytokeratins and villin as evidence of their epithelial cell origin. Human connective tissue matrix from Engelbreth-Holm-Swarm sarcoma cells (Matrigel) modulated their phenotype: alkaline phosphatase activity increased, microvilli developed on their apical surface, and the profile of insulin-like growth factor binding proteins resembled that secreted by differentiated enterocytes. Epithelial cells taken directly from the human fetus as primary cultures and grown as explants on fibroblasts and laminin expressed greater specific enzyme activities in brush border membrane fractions than the cell clone. These activities were enhanced by the luminal molecule sodium butyrate. Thus the sequential addition of connective tissue and luminal molecules to nonmalignant epithelia] cells in vitro induces a spectrum of changes in the epithelial cell phenotype toward full differentiation. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:8755542

Early formation of dental plaque on platic films. 1. Light microscopic observations.

PubMed

Rönström, A; Attström, R; Egelberg, J

1975-02-01

In human subjects with healthy gingiva thin transparent plastic films were applied to the buccal surfaces of premolars in the upper and lower jaws. The films were left in place for peiods of 15, 30, 60, 120 and 240 minutes. The presence of coccoid bacteria, leukocytes and epithelial cells was investigated in an area adjacent to the gingival margin. The results showed that by 15 minutes coccoid bacteria had become attached to the artificial tooth surface. The number of microorganisms gradually increased during the time of the study. Large numbers of cocci and the formation of micro-colonies were observed after 120 and 240 minutes. Increasing numbers of leukocytes and epithelial cells were also found during the period of observation.

Three-dimensional ultrastructure of the surface of the tongue of the rat snake, Elaphe climacophora.

PubMed

Iwasaki, S; Yoshizawa, H; Kawahara, I

1996-05-01

Many studies have been performed to clarify the relationship between behavioral performance of the tongue and Jacobson's organ. The purpose of the present study was to examine the ultrastructural features of the surface of the tongue of the rat snake, Elaphe climacophora, and to delineate the functional relationship between the tongue and Jacobson's organ from a morphological perspective. The three-dimensional ultrastructure of the surface of the tongue of the rat snake Elaphe climacophora was investigated by scanning electron microscopy. Most of the surface of the bifurcated apex of the tongue was relatively smooth. Dome-shaped, hemispherical bulges or microfacets were compactly arranged on the epithelial cell surface over this entire region. Intercellular borders were clearly recognizable as striations. These features were almost the same as those of the dorsal surface of the transitional area between the bifurcated lingual apex and the anterior part of the lingual body. In the posterior half of the lingual body, no microfacets were seen at all. Both microridges and microvilli were compactly distributed on cell surfaces. No evidence was obtained from our ultrastructural analysis for an important role of the lingual apex in the vomeronasal system. By contrast, the epithelial surface of the body of the tongue appeared suitable for retaining stimulating compounds.

Complement Regulator Factor H Mediates a Two-step Uptake of Streptococcus pneumoniae by Human Cells*

PubMed Central

Agarwal, Vaibhav; Asmat, Tauseef M.; Luo, Shanshan; Jensch, Inga; Zipfel, Peter F.; Hammerschmidt, Sven

2010-01-01

Streptococcus pneumoniae, a human pathogen, recruits complement regulator factor H to its bacterial cell surface. The bacterial PspC protein binds Factor H via short consensus repeats (SCR) 8–11 and SCR19–20. In this study, we define how bacterially bound Factor H promotes pneumococcal adherence to and uptake by epithelial cells or human polymorphonuclear leukocytes (PMNs) via a two-step process. First, pneumococcal adherence to epithelial cells was significantly reduced by heparin and dermatan sulfate. However, none of the glycosaminoglycans affected binding of Factor H to pneumococci. Adherence of pneumococci to human epithelial cells was inhibited by monoclonal antibodies recognizing SCR19–20 of Factor H suggesting that the C-terminal glycosaminoglycan-binding region of Factor H mediates the contact between pneumococci and human cells. Blocking of the integrin CR3 receptor, i.e. CD11b and CD18, of PMNs or CR3-expressing epithelial cells reduced significantly the interaction of pneumococci with both cell types. Similarly, an additional CR3 ligand, Pra1, derived from Candida albicans, blocked the interaction of pneumococci with PMNs. Strikingly, Pra1 inhibited also pneumococcal uptake by lung epithelial cells but not adherence. In addition, invasion of Factor H-coated pneumococci required the dynamics of host-cell actin microfilaments and was affected by inhibitors of protein-tyrosine kinases and phosphatidylinositol 3-kinase. In conclusion, pneumococcal entry into host cells via Factor H is based on a two-step mechanism. The first and initial contact of Factor H-coated pneumococci is mediated by glycosaminoglycans expressed on the surface of human cells, and the second step, pneumococcal uptake, is integrin-mediated and depends on host signaling molecules such as phosphatidylinositol 3-kinase. PMID:20504767

Epithelial cell-intrinsic Notch signaling plays an essential role in the maintenance of gut immune homeostasis.

PubMed

Obata, Yuuki; Takahashi, Daisuke; Ebisawa, Masashi; Kakiguchi, Kisa; Yonemura, Shigenobu; Jinnohara, Toshi; Kanaya, Takashi; Fujimura, Yumiko; Ohmae, Masumi; Hase, Koji; Ohno, Hiroshi

2012-03-01

Intestinal epithelial cells (IECs) have important functions as the first line of defense against diverse microorganisms on the luminal surface. Impaired integrity of IEC has been implicated in increasing the risk for inflammatory disorders in the gut. Notch signaling plays a critical role in the maintenance of epithelial integrity by regulating the balance of secretory and absorptive cell lineages, and also by facilitating epithelial cell proliferation. We show in this article that mice harboring IEC-specific deletion of Rbpj (RBP-J(ΔIEC)), a transcription factor that mediates signaling through Notch receptors, spontaneously develop chronic colitis characterized by the accumulation of Th17 cells in colonic lamina propria. Intestinal bacteria are responsible for the development of colitis, because their depletion with antibiotics prevented the development of colitis in RBP-J(ΔIEC) mice. Furthermore, bacterial translocation was evident in the colonic mucosa of RBP-J(ΔIEC) mice before the onset of colitis, suggesting attenuated epithelial barrier functions in these mice. Indeed, RBP-J(ΔIEC) mice displayed increase in intestinal permeability after rectal administration of FITC-dextran. In addition to the defect in physical barrier, loss of Notch signaling led to arrest of epithelial cell turnover caused by downregulation of Hes1, a transcriptional repressor of p27(Kip1) and p57(Kip2). Thus, epithelial cell-intrinsic Notch signaling ensures integrity and homeostasis of IEC, and this mechanism is required for containment of intestinal inflammation.

Characterization of the corneal surface in limbal stem cell deficiency and after transplantation of cultured allogeneic limbal epithelial cells.

PubMed

Chen, Peng; Zhou, Qingjun; Wang, Junyi; Zhao, Xiaowen; Duan, Haoyun; Wang, Yao; Liu, Ting; Xie, Lixin

2016-09-01

The objective of this study was to characterize the changes that occur in the cornea during Limbal Stem Cell Deficiency (LSCD) and on the corneal surface after transplantation of ex vivo cultured allogeneic limbal epithelial transplantation (CALET). Forty-one pannus were analyzed to characterize the changes found in the cornea in LSCD. Nineteen impression cytology samples, including 14 pannus and five corneal buttons, obtained during subsequent procedures from patients who had undergone CALET were examined to assess the effect of CALET and to determine the long-term fate of donor cells. The presence of donor and recipient epithelial cells in each sample was determined by short tandem repeat (STR) amplification and fluorescent-multiplex polymerase chain reaction (PCR). Phenotypic analysis of the epithelium was performed by immunohistochemistry and real-time PCR. The expression of lineage markers was similar between pannus and conjunctivae, but not to corneas. Objective long-term benefits from the transplantation were recorded in most cases. After CALET, the lineage markers in the excised corneal buttons and pannus showed a limbus phenotype. DNA analysis of the 19 cases showed no donor cells present on the ocular surface beyond three months after CALET. LSCD was characterized by ingrowth of abnormal, inflamed tissue with a conjunctival phenotype. CALET was a useful technique for restoring the ocular surface in LSCD. However, such benefits did not necessarily correlate with survival of measurable numbers of donor cells on the ocular surface. The absence of donor DNA beyond three months raises questions regarding the period of ongoing immunosuppression and the origin of the regenerated corneal epithelium.

Therapeutic Effect of Human Adipose Tissue-Derived Mesenchymal Stem Cells in Experimental Corneal Failure Due to Limbal Stem Cell Niche Damage.

PubMed

Galindo, Sara; Herreras, José M; López-Paniagua, Marina; Rey, Esther; de la Mata, Ana; Plata-Cordero, María; Calonge, Margarita; Nieto-Miguel, Teresa

2017-10-01

Limbal stem cells are responsible for the continuous renewal of the corneal epithelium. The destruction or dysfunction of these stem cells or their niche induces limbal stem cell deficiency (LSCD) leading to visual loss, chronic pain, and inflammation of the ocular surface. To restore the ocular surface in cases of bilateral LSCD, an extraocular source of stem cells is needed to avoid dependence on allogeneic limbal stem cells that are difficult to obtain, isolate, and culture. The aim of this work was to test the tolerance and the efficacy of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) to regenerate the ocular surface in two experimental models of LSCD that closely resemble different severity grades of the human pathology. hAT-MSCs transplanted to the ocular surface of the partial and total LSCD models developed in rabbits were well tolerated, migrated to inflamed tissues, reduced inflammation, and restrained the evolution of corneal neovascularization and corneal opacity. The expression profile of the corneal epithelial cell markers CK3 and E-cadherin, and the limbal epithelial cell markers CK15 and p63 was lost in the LSCD models, but was partially recovered after hAT-MSC transplantation. For the first time, we demonstrated that hAT-MSCs improve corneal and limbal epithelial phenotypes in animal LSCD models. These results support the potential use of hAT-MSCs as a novel treatment of ocular surface failure due to LSCD. hAT-MSCs represent an available, non-immunogenic source of stem cells that may provide therapeutic benefits in addition to reduce health care expenses. Stem Cells 2017;35:2160-2174. © 2017 AlphaMed Press.

Treatment of Silk Fibroin with Poly(ethylene glycol) for the Enhancement of Corneal Epithelial Cell Growth

PubMed Central

Suzuki, Shuko; Dawson, Rebecca A.; Chirila, Traian V.; Shadforth, Audra M. A.; Hogerheyde, Thomas A.; Edwards, Grant A.; Harkin, Damien G.

2015-01-01

A silk protein, fibroin, was isolated from the cocoons of the domesticated silkworm (Bombyx mori) and cast into membranes to serve as freestanding templates for tissue-engineered corneal cell constructs to be used in ocular surface reconstruction. In this study, we sought to enhance the attachment and proliferation of corneal epithelial cells by increasing the permeability of the fibroin membranes and the topographic roughness of their surface. By mixing the fibroin solution with poly(ethylene glycol) (PEG) of molecular weight 300 Da, membranes were produced with increased permeability and with topographic patterns generated on their surface. In order to enhance their mechanical stability, some PEG-treated membranes were also crosslinked with genipin. The resulting membranes were thoroughly characterized and compared to the non-treated membranes. The PEG-treated membranes were similar in tensile strength to the non-treated ones, but their elastic modulus was higher and elongation lower, indicating enhanced rigidity. The crosslinking with genipin did not induce a significant improvement in mechanical properties. In cultures of a human-derived corneal epithelial cell line (HCE-T), the PEG treatment of the substratum did not improve the attachment of cells and it enhanced only slightly the cell proliferation in the longer term. Likewise, primary cultures of human limbal epithelial cells grew equally well on both non-treated and PEG-treated membranes, and the stratification of cultures was consistently improved in the presence of an underlying culture of irradiated 3T3 feeder cells, irrespectively of PEG-treatment. Nevertheless, the cultures grown on the PEG-treated membranes in the presence of feeder cells did display a higher nuclear-to-cytoplasmic ratio suggesting a more proliferative phenotype. We concluded that while the treatment with PEG had a significant effect on some structural properties of the B. mori silk fibroin (BMSF) membranes, there were minimal gains in the performance of these materials as a substratum for corneal epithelial cell growth. The reduced mechanical stability of freestanding PEG-treated membranes makes them a less viable choice than the non-treated membranes. PMID:26034883

Comparison of ultrastructure, tight junction-related protein expression and barrier function of human corneal epithelial cells cultivated on amniotic membrane with and without air-lifting.

PubMed

Ban, Yuriko; Cooper, Leanne J; Fullwood, Nigel J; Nakamura, Takahiro; Tsuzuki, Masakatsu; Koizumi, Noriko; Dota, Atsuyoshi; Mochida, Chikako; Kinoshita, Shigeru

2003-06-01

To evaluate the usefulness of the air-lifting technique for culturing corneal limbal epithelial cells on amniotic membrane (AM) for use in ocular surface reconstruction. A cultured sheet that has a good barrier function should be better for this purpose. In corneal epithelium, tight junctions (TJ) play a vital role in the barrier function. The TJ complex includes the integral transmembrane proteins occludin and the claudins, and some membrane-associated proteins such as ZO-1. In this paper, we investigated the barrier function and the expression of TJ related proteins. Corneal limbal epithelium obtained from donor corneas and cultivated on acellular AM was divided into two groups. These were the non-air-lifting (Non-AL) group, which was continuously submerged in medium, and the air-lifting (AL) group, which was submerged in medium for 3 weeks, then exposed to air by lowering the medium level. Morphology and the permeability to horseradish peroxidase (HRP) were determined by electron microscopy. Tight junction (TJ)-related protein and mRNA expression changes were assessed by immunoblotting and reverse transcription-polymerase chain reaction. The cultures of both groups formed 4-5-layer-thick, well-stratified epithelium. The AL cultures had tightly packed epithelial cells with all the HRP/diaminobenzidine (DAB) reaction product accumulated on the apical surface of the superficial cells. The Non-AL culture, by contrast, had more loosely packed epithelial cells with larger intercellular spaces. The HRP/DAB reaction product penetrated the intercellular space to a depth of 3-4 cell layers. Statistically, there was a significant difference in intercellular spaces and desmosome count in the superficial cells between the groups. With AL, TJ-related proteins localized at the apical portion of the lateral membrane. TJ-related protein and mRNA amounts were not changed by AL while claudin subtype expression became more consistent and closer to that of in vivo corneal epithelium. The AL technique reduces intercellular spaces in the superficial cells and promotes the formation of the barrier function. It is useful in culturing corneal epithelial cells for use in ocular surface reconstruction.

Dual pulse-chase microscopy reveals early divergence in the biosynthetic trafficking of the Na,K-ATPase and E-cadherin

PubMed Central

Farr, Glen A.; Hull, Michael; Stoops, Emily H.; Bateson, Rosalie; Caplan, Michael J.

2015-01-01

Recent evidence indicates that newly synthesized membrane proteins that share the same distributions in the plasma membranes of polarized epithelial cells can pursue a variety of distinct trafficking routes as they travel from the Golgi complex to their common destination at the cell surface. In most polarized epithelial cells, both the Na,K-ATPase and E-cadherin are localized to the basolateral domains of the plasma membrane. To examine the itineraries pursued by newly synthesized Na,K-ATPase and E-cadherin in polarized MDCK epithelial cells, we used the SNAP and CLIP labeling systems to fluorescently tag temporally defined cohorts of these proteins and observe their behaviors simultaneously as they traverse the secretory pathway. These experiments reveal that E-cadherin is delivered to the cell surface substantially faster than is the Na,K-ATPase. Furthermore, the surface delivery of newly synthesized E-cadherin to the plasma membrane was not prevented by the 19°C temperature block that inhibits the trafficking of most proteins, including the Na,K-ATPase, out of the trans-Golgi network. Consistent with these distinct behaviors, populations of newly synthesized E-cadherin and Na,K-ATPase become separated from one another within the trans-Golgi network, suggesting that they are sorted into different carrier vesicles that mediate their post-Golgi trafficking. PMID:26424804

Temperature influences on water permeability and chlorpyrifos uptake in aquatic insects with differing respiratory strategies.

PubMed

Buchwalter, David B; Jenkins, Jeffrey J; Curtis, Lawrence R

2003-11-01

Aquatic insects have evolved diverse respiratory strategies that range from breathing atmospheric air to breathing dissolved oxygen. These strategies result in vast morphological differences among taxa in terms of exchange epithelial surface areas that are in direct contact with the surrounding water that, in turn, affect physiological processes. This paper examines the effects of acute temperature shifts on water permeability and chlorpyrifos uptake in aquatic insects with different respiratory strategies. While considerable differences existed in water permeability among the species tested, acute temperature shifts raised water influx rates similarly in air-breathing and gill-bearing taxa. This contrasts significantly with temperature-shift effects on chlorpyrifos uptake. Temperature shifts of 4.5 degrees C increased 14C-chlorpyrifos accumulation rates in the gill-bearing mayfly Cinygma sp. and in the air-breathing hemipteran Sigara washingtonensis. However, the temperature-induced increase in 14C-chlorpyrifos uptake after 8 h of exposure was 2.75-fold higher in Cinygma than in Sigara. Uptake of 14C-chlorpyrifos was uniformly higher in Cinygma than in Sigara in all experiments. These findings suggest that organisms with relatively large exchange epithelial surface areas are potentially more vulnerable to both osmoregulatory distress as well as contaminant accumulation. Temperature increases appear more likely to impact organisms that have relatively large exchange epithelial surface areas, both as an individual stressor and in combination with additional stressors such as contaminants.

Intraocular lens bioactivity tested using rabbit corneal tissue cultures.

PubMed

Linnola, R J; Salonen, J I; Happonen, R P

1999-11-01

To evaluate the effects of different intraocular lens (IOL) materials on epithelial cell growth to test the sandwich theory; i.e., a bioactivity-based explanation of posterior capsule opacification (PCO) after cataract surgery. Central Hospital, Vaasa, and Institute of Dentistry and Turku Center for Biomaterials, University of Turku, Finland. Rabbit corneal tissue cultures were set up on poly(methyl methacrylate) (PMMA), heparin-surface-modified (HSM) PMMA, silicone, acrylate, and hydrogel IOLs for 1 week. The tissue consisted of intact epithelium and half the thickness of the corneal stroma, which was placed against the IOL. The growth of the epithelium was examined by light microscopy to evaluate the attachment of the corneal explant to the IOL surface. All tissue samples grew well under the culture conditions. When grown on PMMA, HSM PMMA, silicone, and hydrogel, the tissue did not attach to the IOL or the epithelium grew around the explant, suggesting that the attachment of the stroma to the IOL was poor or nonexistent. Some explants on acrylate IOLs attached directly to the IOL surface with no epithelial ingrowth between the stroma and the IOL. This tissue culture method can be used to examine the behavior of corneal tissue in contact with different IOL materials. The results suggest that the acrylate IOL may have bioactive properties. This, with the lens optic's square edge, may hinder lens epithelial cell proliferation and thus prevent PCO.

Towards early detection of cervical cancer: Fractal dimension of AFM images of human cervical epithelial cells at different stages of progression to cancer.

PubMed

Guz, Nataliia V; Dokukin, Maxim E; Woodworth, Craig D; Cardin, Andrew; Sokolov, Igor

2015-10-01

We used AFM HarmoniX modality to analyse the surface of individual human cervical epithelial cells at three stages of progression to cancer, normal, immortal (pre-malignant) and carcinoma cells. Primary cells from 6 normal strains, 6 cancer, and 6 immortalized lines (derived by plasmid DNA-HPV-16 transfection of cells from 6 healthy individuals) were tested. This cell model allowed for good control of the cell phenotype down to the single cell level, which is impractical to attain in clinical screening tests (ex-vivo). AFM maps of physical (nonspecific) adhesion are collected on fixed dried cells. We show that a surface parameter called fractal dimension can be used to segregate normal from both immortal pre-malignant and malignant cells with sensitivity and specificity of more than 99%. The reported method of analysis can be directly applied to cells collected in liquid cytology screening tests and identified as abnormal with regular optical methods to increase sensitivity. Despite cervical smear screening, sometimes it is very difficult to differentiate cancers cells from pre-malignant cells. By using AFM to analyze the surface properties of human cervical epithelial cells, the authors were able to accurately identify normal from abnormal cells. This method could augment existing protocols to increase diagnostic accuracy. Copyright © 2015. Published by Elsevier Inc.

Treatment with sodium hyaluronate eye drops in a patient who had early-onset bleb leakage after trabeculectomy with mitomycin C

PubMed Central

Sagara, Hideto; Sekiryu, Tetsuju; Noji, Hiroki; Ogasawara, Masashi; Imaizumi, Kimihiro; Yago, Keiko

2015-01-01

We present the case of a 47-year-old man who had bilateral proliferative diabetic retinopathy and neovascular glaucoma. Schirmer I test revealed tear secretions of 5 mm and 3 mm in the right and left eyes, respectively. Tear breakup times in the right and left eyes were 7 and 8 seconds, respectively. The ocular surface staining in both eyes was scored as Grade 1 as per the Oxford scheme. Retinal photocoagulation was performed for correction of the proliferative diabetic retinopathy and rubeosis iridis, which resolved with treatment. However, the intraocular pressure in the left eye could not be adequately controlled. Therefore, trabeculectomy with mitomycin C using limbal-based conjunctival flap was performed. Three hours after the surgery, the patient developed a large and diffuse filtering bleb, but no leakage occurred from the conjunctival scar. However, on the first postoperative day, leakage was noted and the conjunctiva was at the leakage point. The leakage resolved transiently, but recurred the next day. Severe keratoconjunctival epithelial failure was detected, and the patient was administrated 0.1% sodium hyaluronate eye drops six times daily. The epithelial failure improved, and many microcysts were detected on the bleb surface where the epithelial failure improved. The leakage resolved 2 days after initiation of the sodium hyaluronate eye drops. The microcysts disappeared and the bleb surface became smooth 1 month later. PMID:26664245

Treatment with sodium hyaluronate eye drops in a patient who had early-onset bleb leakage after trabeculectomy with mitomycin C.

PubMed

Sagara, Hideto; Sekiryu, Tetsuju; Noji, Hiroki; Ogasawara, Masashi; Imaizumi, Kimihiro; Yago, Keiko

2015-01-01

We present the case of a 47-year-old man who had bilateral proliferative diabetic retinopathy and neovascular glaucoma. Schirmer I test revealed tear secretions of 5 mm and 3 mm in the right and left eyes, respectively. Tear breakup times in the right and left eyes were 7 and 8 seconds, respectively. The ocular surface staining in both eyes was scored as Grade 1 as per the Oxford scheme. Retinal photocoagulation was performed for correction of the proliferative diabetic retinopathy and rubeosis iridis, which resolved with treatment. However, the intraocular pressure in the left eye could not be adequately controlled. Therefore, trabeculectomy with mitomycin C using limbal-based conjunctival flap was performed. Three hours after the surgery, the patient developed a large and diffuse filtering bleb, but no leakage occurred from the conjunctival scar. However, on the first postoperative day, leakage was noted and the conjunctiva was at the leakage point. The leakage resolved transiently, but recurred the next day. Severe keratoconjunctival epithelial failure was detected, and the patient was administrated 0.1% sodium hyaluronate eye drops six times daily. The epithelial failure improved, and many microcysts were detected on the bleb surface where the epithelial failure improved. The leakage resolved 2 days after initiation of the sodium hyaluronate eye drops. The microcysts disappeared and the bleb surface became smooth 1 month later.

Effects of DA-6034, a flavonoid derivative, on mucin-like glycoprotein and ocular surface integrity in a rabbit model.

PubMed

Choi, Seul Min; Seo, Mi Jeong; Lee, Yeong Geon; Lee, Min Jung; Jeon, Hyung Jun; Kang, Kyung Koo; Ahn, Byoung Ok; Yoo, Moohi

2009-01-01

This study was designed to assess whether DA-6034 (7-carboxymethyloxy-3',4',5-trimethoxy flavone monohydrate), a new synthetic derivative of eupatilin, increases secretion of mucin-like glycoprotein and some mucins species in conjunctiva and cornea, and contributes to the preservation of ocular surface integrity. Human conjunctival and corneal epithelial cells were incubated with DA-6034 (1-250 microM). To investigate mucin secreting activity more directly, isolated rat conjunctival goblet cells were also used. Corneal protection was investigated using a desiccation-induced rabbit model of dry eye syndrome. It was found that DA-6034 increased mucin-like glycoprotein levels of both conjunctival and corneal epithelial cells at concentrations above 100 microM. Using human conjunctival epithelial cells, it was demonstrated that treatment with DA-6034 (200 microM) significantly increased production of some mucins species including MUC1, MUC2, MUC4, MUC5AC, MUC5B, and MUC16. DA-6034 also significantly increased MUC5AC production from conjunctival goblet cells isolated from rats. In the rabbit desiccation model, an ophthalmic suspension containing 3% DA-6034 significantly reduced corneal damage induced by desiccation. These results suggest that DA-6034 is a good candidate for treatment of dry eye through maintaining ocular surface integrity, which might be related to mucin secretion.

Temperature influences on water permeability and chlorpyrifos uptake in aquatic insects with differing respiratory strategies

USGS Publications Warehouse

Buchwalter, D.B.; Jenkins, J.J.; Curtis, L.R.

2003-01-01

Aquatic insects have evolved diverse respiratory strategies that range from breathing atmospheric air to breathing dissolved oxygen. These strategies result in vast morphological differences among taxa in terms of exchange epithelial surface areas that are in direct contact with the surrounding water that, in turn, affect physiological processes. This paper examines the effects of acute temperature shifts on water permeability and chlorpyrifos uptake in aquatic insects with different respiratory strategies. While considerable differences existed in water permeability among the species tested, acute temperature shifts raised water influx rates similarly in air-breathing and gill-bearing taxa. This contrasts significantly with temperature-shift effects on chlorpyrifos uptake. Temperature shifts of 4.5??C increased 14C-chlorpyrifos accumulation rates in the gill-bearing mayfly Cinygma sp. and in the air-breathing hemipteran Sigara washingtonensis. However, the temperature-induced increase in 14C-chlorpyrifos uptake after 8 h of exposure was 2.75-fold higher in Cinygma than in Sigara. Uptake of 14C-chlorpyrifos was uniformly higher in Cinygma than in Sigara in all experiments. These findings suggest that organisms with relatively large exchange epithelial surface areas are potentially more vulnerable to both osmoregulatory distress as well as contaminant accumulation. Temperature increases appear more likely to impact organisms that have relatively large exchange epithelial surface areas, both as an individual stressor and in combination with additional stressors such as contaminants.

Generation of Alveolar Epithelial Spheroids via Isolated Progenitor Cells from Human Pluripotent Stem Cells

PubMed Central

Gotoh, Shimpei; Ito, Isao; Nagasaki, Tadao; Yamamoto, Yuki; Konishi, Satoshi; Korogi, Yohei; Matsumoto, Hisako; Muro, Shigeo; Hirai, Toyohiro; Funato, Michinori; Mae, Shin-Ichi; Toyoda, Taro; Sato-Otsubo, Aiko; Ogawa, Seishi; Osafune, Kenji; Mishima, Michiaki

2014-01-01

Summary No methods for isolating induced alveolar epithelial progenitor cells (AEPCs) from human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) have been reported. Based on a study of the stepwise induction of alveolar epithelial cells (AECs), we identified carboxypeptidase M (CPM) as a surface marker of NKX2-1+ “ventralized” anterior foregut endoderm cells (VAFECs) in vitro and in fetal human and murine lungs. Using SFTPC-GFP reporter hPSCs and a 3D coculture system with fetal human lung fibroblasts, we showed that CPM+ cells isolated from VAFECs differentiate into AECs, demonstrating that CPM is a marker of AEPCs. Moreover, 3D coculture differentiation of CPM+ cells formed spheroids with lamellar-body-like structures and an increased expression of surfactant proteins compared with 2D differentiation. Methods to induce and isolate AEPCs using CPM and consequently generate alveolar epithelial spheroids would aid human pulmonary disease modeling and regenerative medicine. PMID:25241738

Focal epithelial hyperplasia arising after delivery of metal-ceramic fixed dental prosthesis.

PubMed

Park, Min-Woo; Cho, Young-Ah; Kim, Soung-Min; Myoung, Hoon; Lee, Jong-Ho; Lee, Suk-Keun

2014-12-01

Focal epithelial hyperplasia (FEH) is a human papillomavirus (HPV)-induced alteration of the oral mucosa that presents with a clinically distinct appearance. While other HPV-infected lesions such as squamous papilloma, verruca vulgaris, and condyloma acuminatum involve the skin, oral mucosa, and genital mucosa, FEH occurs only in the oral mucosa. The affected oral mucosa exhibits multiple papules and nodules with each papule/nodule being flat-topped or sessile. The affected region resembles the normal color of oral mucosa rather than appearing as a white color since the epithelial surface is not hyperkeratinized. Almost all cases present with multiple sites of occurrence. This rare, benign epithelial proliferation is related to low-risk HPV, especially HPV-13 and -32, and is not transformed into carcinoma. We report a case of FEH that arose on the attached gingiva of an East Asian male adult related to prosthesis without detection of any HPV subtype in HPV DNA chip and sequencing.

γδ T cells in homeostasis and host defence of epithelial barrier tissues

PubMed Central

Nielsen, Morten M.; Witherden, Deborah A.; Havran, Wendy L.

2018-01-01

Epithelial surfaces line the body and provide a critical interface between the body and the external environment which is essential to maintaining the symbiotic relationship between the host and the microbiome. Tissue-resident epithelial γδ T cells represent a major T cell population in epithelia and are ideally positioned to perform barrier surveillance and aid in tissue homeostasis and repair. In this review we focus on the intraepithelial γδ compartment in the two largest epithelial tissues in the body, namely the epidermis and intestine, and provide a comprehensive overview of the crucial contributions of intraepithelial γδ cells at these sites to tissue integrity and repair, host homeostasis and host protection in the context of the symbiotic relationship with the microbiome and during pathogen clearance. Finally, we address epithelia-specific butyrophilin-like molecules and touch upon their emerging role in selectively shaping and regulating epidermal and intestinal γδ T cell repertoires. PMID:28920588

Phenotypic Plasticity Determines Cancer Stem Cell Therapeutic Resistance in Oral Squamous Cell Carcinoma.

PubMed

Biddle, Adrian; Gammon, Luke; Liang, Xiao; Costea, Daniela Elena; Mackenzie, Ian C

2016-02-01

Cancer stem cells (CSCs) drive tumour spread and therapeutic resistance, and can undergo epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) to switch between epithelial and post-EMT sub-populations. Examining oral squamous cell carcinoma (OSCC), we now show that increased phenotypic plasticity, the ability to undergo EMT/MET, underlies increased CSC therapeutic resistance within both the epithelial and post-EMT sub-populations. The post-EMT CSCs that possess plasticity exhibit particularly enhanced therapeutic resistance and are defined by a CD44(high)EpCAM(low/-) CD24(+) cell surface marker profile. Treatment with TGFβ and retinoic acid (RA) enabled enrichment of this sub-population for therapeutic testing, through which the endoplasmic reticulum (ER) stressor and autophagy inhibitor Thapsigargin was shown to selectively target these cells. Demonstration of the link between phenotypic plasticity and therapeutic resistance, and development of an in vitro method for enrichment of a highly resistant CSC sub-population, provides an opportunity for the development of improved chemotherapeutic agents that can eliminate CSCs.

An Improved Unsupervised Image Segmentation Evaluation Approach Based on - and Over-Segmentation Aware

NASA Astrophysics Data System (ADS)

Su, Tengfei

2018-04-01

In this paper, an unsupervised evaluation scheme for remote sensing image segmentation is developed. Based on a method called under- and over-segmentation aware (UOA), the new approach is improved by overcoming the defect in the part of estimating over-segmentation error. Two cases of such error-prone defect are listed, and edge strength is employed to devise a solution to this issue. Two subsets of high resolution remote sensing images were used to test the proposed algorithm, and the experimental results indicate its superior performance, which is attributed to its improved OSE detection model.

Transition of the Combustion of Condensed Systems into an Explosion

DTIC Science & Technology

1975-02-06

tubes iwholly L 1 ed,’ with exrlnsives. Figure Cb de ,-cts the tube which w-.as used ty Gi’pson ar’J !Ma’L"ek for the study of the transition of ccrtUS...continuous optical recording c_’ the trocess of the tlii-sitiOTI CT’ crmsr.ion into aCetonatio.. it is schematically’ de -cicted on rg c The tube...r thlis zur-ose Zverev designed a special electronic amelifier. hIs amplifIer had a sc.*w resnonse, which made it rossible to use the ciezoelectric

Ural-Tweed Bighorn Sheep Investigation.

DTIC Science & Technology

1979-01-01

use of Isouth, southwe-st, and west el)-Osed overs -teepenod terrain alonr~ the east escarpment of Lirke KoocanusQ. Five habitat types, PSME/ SYAL ...8217 SYAL PSIM, PHIiA PS:: , L7 a b Jan. a2/7b -,4/47 14/47 Feb. 9/31 9 ,𔄁 1’ , Mar. 12/43 1/4 10/36 3/11/ A, r. 9/50 2/12 7/3, May 3/1i 12/71 2/11 Ji...of the sheep use Table 13). In order of apparent decreasing importance, these habitat types were- 1) PSME/ SYAL , 2) PSME/CARU, 3) PSME/PHMA, 4) PSME

Effects of Hydrostatic Pressure on Carcinogenic Properties of Epithelia.

PubMed

Tokuda, Shinsaku; Kim, Young Hak; Matsumoto, Hisako; Muro, Shigeo; Hirai, Toyohiro; Mishima, Michiaki; Furuse, Mikio

2015-01-01

The relationship between chronic inflammation and cancer is well known. The inflammation increases the permeability of blood vessels and consequently elevates pressure in the interstitial tissues. However, there have been only a few reports on the effects of hydrostatic pressure on cultured cells, and the relationship between elevated hydrostatic pressure and cell properties related to malignant tumors is less well understood. Therefore, we investigated the effects of hydrostatic pressure on the cultured epithelial cells seeded on permeable filters. Surprisingly, hydrostatic pressure from basal to apical side induced epithelial stratification in Madin-Darby canine kidney (MDCK) I and Caco-2 cells, and cavities with microvilli and tight junctions around their surfaces were formed within the multi-layered epithelia. The hydrostatic pressure gradient also promoted cell proliferation, suppressed cell apoptosis, and increased transepithelial ion permeability. The inhibition of protein kinase A (PKA) promoted epithelial stratification by the hydrostatic pressure whereas the activation of PKA led to suppressed epithelial stratification. These results indicate the role of the hydrostatic pressure gradient in the regulation of various epithelial cell functions. The findings in this study may provide clues for the development of a novel strategy for the treatment of the carcinoma.

Effects of Hydrostatic Pressure on Carcinogenic Properties of Epithelia

PubMed Central

Tokuda, Shinsaku; Kim, Young Hak; Matsumoto, Hisako; Muro, Shigeo; Hirai, Toyohiro; Mishima, Michiaki; Furuse, Mikio

2015-01-01

The relationship between chronic inflammation and cancer is well known. The inflammation increases the permeability of blood vessels and consequently elevates pressure in the interstitial tissues. However, there have been only a few reports on the effects of hydrostatic pressure on cultured cells, and the relationship between elevated hydrostatic pressure and cell properties related to malignant tumors is less well understood. Therefore, we investigated the effects of hydrostatic pressure on the cultured epithelial cells seeded on permeable filters. Surprisingly, hydrostatic pressure from basal to apical side induced epithelial stratification in Madin-Darby canine kidney (MDCK) I and Caco-2 cells, and cavities with microvilli and tight junctions around their surfaces were formed within the multi-layered epithelia. The hydrostatic pressure gradient also promoted cell proliferation, suppressed cell apoptosis, and increased transepithelial ion permeability. The inhibition of protein kinase A (PKA) promoted epithelial stratification by the hydrostatic pressure whereas the activation of PKA led to suppressed epithelial stratification. These results indicate the role of the hydrostatic pressure gradient in the regulation of various epithelial cell functions. The findings in this study may provide clues for the development of a novel strategy for the treatment of the carcinoma. PMID:26716691

Deciliation Is Associated with Dramatic Remodeling of Epithelial Cell Junctions and Surface Domains

PubMed Central

Overgaard, Christian E.; Sanzone, Kaitlin M.; Spiczka, Krystle S.; Sheff, David R.; Sandra, Alexander

2009-01-01

Stress-induced shedding of motile cilia (autotomy) has been documented in diverse organisms and likely represents a conserved cellular reaction. However, little is known about whether primary cilia are shed from mammalian epithelial cells and what impact deciliation has on polarized cellular organization. We show that several chemically distinct agents trigger autotomy in epithelial cells. Surprisingly, deciliation is associated with a significant, but reversible increase in transepithelial resistance. This reflects substantial reductions in tight junction proteins associated with “leaky” nephron segments (e.g., claudin-2). At the same time, apical trafficking of gp80/clusterin and gp114/CEACAM becomes randomized, basal-lateral delivery of Na,K-ATPase is reduced, and expression of the nonciliary apical protein gp135/podocalyxin is greatly decreased. However, ciliogenesis-impaired MDCK cells do not undergo continual junction remodeling, and mature cilia are not required for autotomy-associated remodeling events. Deciliation and epithelial remodeling may be mechanistically linked processes, because RNAi-mediated reduction of Exocyst subunit Sec6 inhibits ciliary shedding and specifically blocks deciliation-associated down-regulation of claudin-2 and gp135. We propose that ciliary autotomy represents a signaling pathway that impacts the organization and function of polarized epithelial cells. PMID:19005211

Desquamation takes center stage at the origin of proliferative inflammatory atrophy, epithelial-mesenchymal transition, and stromal growth in benign prostate hyperplasia.

PubMed

Ferrucci, Danilo; Biancardi, Manoel F; Nishan, Umar; Rosa-Ribeiro, Rafaela; Carvalho, Hernandes F

2017-11-01

In this commentary, we propose a relationship between desquamation, initially described as the collective detachment and deletion of epithelial cell in the prostate gland after castration, and proliferative inflammatory atrophy (PIA) and stromal growth in benign prostate hyperplasia (BPH). First, in response to diverse stimuli, including inflammatory mediators, epithelial cells desquamate and leave a large surface of the luminal side of the basement membrane (BM) exposed. Basal cells are activated into intermediate-type cells, which change morphology to cover and remodel the exposed BM (simple atrophy) to a new physiological demand (such as in the hypoandrogen environment, simulated by surgical and/or chemical castration) and/or to support re-epithelialization (under normal androgen levels). In the presence of inflammation (that might be the cause of desquamation), the intermediate-type cells proliferate and characterize PIA. Second, in other circumstances, desquamation is an early step of epithelial-to-mesenchymal transition (EMT), which contributes to stromal growth, as suggested by some experimental models of BPH. The proposed associations correlate unexplored cell behaviors and reveal the remarkable plasticity of the prostate epithelium that might be at the origin of prostate diseases. © 2017 International Federation for Cell Biology.

Unusually high incidence of multifocal epithelial hyperplasia in children of the Nahuatl population of Mexico.

PubMed

Ledesma-Montes, Constantino; Mendez-Mendoza, Amilcar

2017-01-01

Multifocal epithelial hyperplasia is an uncommon disease of the oral mucosa caused by the human papilloma virus. To study the clinical and pathological findings of multifocal epithelial hyperplasia detected during an oral examination of 343 Mexican Nahuatl children from a single primary school in El Paso de Cupilco, Mexico. A thorough oral examination was performed in all children and clinical data (age, gender, location and number of lesions) were documented and analyzed. Multifocal epithelial hyperplasia was diagnosed in 110 of the 343 children (32.3%). The ages of the children varied from 5 to 15 years, and of these, 56.3% were girls. The lesions were asymptomatic, 0.2 to 3.0 cm in diameter, soft, round to oval, smooth surfaced, sessile papulonodules, similar in colour to that of the surrounding mucosa. The lesions were commonly seen on the buccal mucosa and tongue, and most affected children (85%) had less than 5 lesions. Children in the 7 to 10 years age group were most often affected. Human papillomavirus typing was not done owing to a lack of facilities. There is a high incidence of multifocal epithelial hyperplasia in Nahuatl children with a predilection for females.

New directions at NSF

NASA Astrophysics Data System (ADS)

Harvey, Albert B.

1995-10-01

The mission and scope of the National Science Foundation (NSF) and lightwave technology will be very briefly discussed. The focus of the presentation will be directed toward changes in research support that are taking place and the opportunities we have for aiming our research to meet the challenges and needs that face the nation. In the USA it is very clear that defense oriented research is downsizing and is being redirected into economy driven aresas, such as manufacturing, business, and industry. For those researchers who are willing to move into these areas and find a niche, the rewards may be very great. Industrial research partners should also seize these opportunities to enhance their resources in an otherwise bleak future for industrial support of basic research in lightwave technology and many other reserach disciplines. These activities of bringing together industry and academia will have the value added benefit of providing increased job opportunities for students. An outline of some of these opportunities and incentives will be presented. On the international front, there has never been a better time for the encouragement of joint research and collaboration across borders. The economic potential for involvement in Eastern Europe and Asia are enormous. Agencies like ourselves are open to help support of visiting scientist/engineer exchange, international conferences and forums and support of innovative ideas to help further enhance economic developemnt of the world and hence the quality of life. The presence of the Russian delegation here at these SPIE meetings in in part the result of NSF support. Concomitant with these changes is a growing interest in education. Academia is gradually realizing that education includes training for students to acquire jobs and hence we complete the cycle of the importance of interacting with industry. At the NSF a major new initiative is being introduced in Optical Science and Engineering (OSE). This effort has been created as an outgrowth of the NRC study being conducted in parallel under the same name. OSE is based on the fact that optics is a very interdisciplinary area and special emphasis on the interface between the relevant areas is where the action is. Lightwave technology and the implementation of organic materials to optoelectronic applications is clearly an area which has tremendous potential for economic impact and it fits the criteria for the OSE initiative. It is also exciting, challenging, and personally rewarding. But organic materials have been promising for quite some time and some are getting impatient. To provide credibility to those who support this research (governement, idustry, etc.), we must turn our attention to ways in which we can accelerate the transition from the laboratory discovery to the consumer. In this way everyone will become a winner.

Quantification of confocal images of biofilms grown on irregular surfaces

PubMed Central

Ross, Stacy Sommerfeld; Tu, Mai Han; Falsetta, Megan L.; Ketterer, Margaret R.; Kiedrowski, Megan R.; Horswill, Alexander R.; Apicella, Michael A.; Reinhardt, Joseph M.; Fiegel, Jennifer

2014-01-01

Bacterial biofilms grow on many types of surfaces, including flat surfaces such as glass and metal and irregular surfaces such as rocks, biological tissues and polymers. While laser scanning confocal microscopy can provide high-resolution images of biofilms grown on any surface, quantification of biofilm-associated bacteria is currently limited to bacteria grown on flat surfaces. This can limit researchers studying irregular surfaces to qualitative analysis or quantification of only the total bacteria in an image. In this work, we introduce a new algorithm called modified connected volume filtration (MCVF) to quantify bacteria grown on top of an irregular surface that is fluorescently labeled or reflective. Using the MCVF algorithm, two new quantification parameters are introduced. The modified substratum coverage parameter enables quantification of the connected-biofilm bacteria on top of the surface and on the imaging substratum. The utility of MCVF and the modified substratum coverage parameter were shown with Pseudomonas aeruginosa and Staphylococcus aureus biofilms grown on human airway epithelial cells. A second parameter, the percent association, provides quantified data on the colocalization of the bacteria with a labeled component, including bacteria within a labeled tissue. The utility of quantifying the bacteria associated with the cell cytoplasm was demonstrated with Neisseria gonorrhoeae biofilms grown on cervical epithelial cells. This algorithm provides more flexibility and quantitative ability to researchers studying biofilms grown on a variety of irregular substrata. PMID:24632515

Apical Cyst Theory: a Missing Link.

PubMed

Huang, George T-J

2010-10-05

The mechanism of the formation of apical cyst has been elusive. Several theories have long been proposed and discussed speculating how an apical cyst is developed and formed in the jaw bone resulting from endododontic infection. Two popular theories are the nutritional deficiency theory and the abscess theory. The nutritional deficiency theory assumes that the over proliferated epithelial cells will form a ball mass such that the cells in the center of the mass will be deprived of nutrition. The abscess theory postulates that when an abscess cavity is formed in connective tissue, epithelial cells proliferate and line the preexisting cavity because of their inherent tendency to cover exposed connective tissue surfaces. Based on the nature of epithelial cells and the epithelium, nutritional theory is a fairy tale, while abscess theory at best just indicates that abscess may be one of the factors that allows the stratified epithelium to form but not to explain a mechanism that makes the cyst to form. Apical cyst formation is the result of proliferation of resting epithelial cells, due to inflammation, to a sufficient number such that they are able to form a polarized and stratified epithelial lining against dead tissues or foreign materials. These stratified epithelial lining expands along the dead tissue or foreign materials and eventually wrap around them as a spherical sac, i.e. a cyst. The space in the sac is considered the external environment separating the internal (tissue) environment - the natural function of epithelium. This theory may be tested by introducing a biodegradable device able to slowly release epithelial cell mitogens in an in vivo environment implanted with epithelial cells next to a foreign object. This will allow the cells to continuously proliferate which may form a cystic sac wrapping around the foreign object.

Coupling between apical tension and basal adhesion allow epithelia to collectively sense and respond to substrate topography over long distances.

PubMed

Broaders, Kyle E; Cerchiari, Alec E; Gartner, Zev J

2015-12-01

Epithelial sheets fold into complex topographies that contribute to their function in vivo. Cells can sense and respond to substrate topography in their immediate vicinity by modulating their interfacial mechanics, but the extent to which these mechanical properties contribute to their ability to sense substrate topography across length scales larger than a single cell has not been explored in detail. To study the relationship between the interfacial mechanics of single cells and their collective behavior as tissues, we grew cell-sheets on substrates engraved with surface features spanning macroscopic length-scales. We found that many epithelial cell-types sense and respond to substrate topography, even when it is locally nearly planar. Cells clear or detach from regions of local negative curvature, but not from regions with positive or no curvature. We investigated this phenomenon using a finite element model where substrate topography is coupled to epithelial response through a balance of tissue contractility and adhesive forces. The model correctly predicts the focal sites of cell-clearing and epithelial detachment. Furthermore, the model predicts that local tissue response to substrate curvature is a function of the surrounding topography of the substrate across long distances. Analysis of cell-cell and cell-substrate contact angles suggests a relationship between these single-cell interfacial properties, epithelial interfacial properties, and collective epithelial response to substrate topography. Finally, we show that contact angles change upon activation of oncogenes or inhibition of cell-contractility, and that these changes correlate with collective epithelial response. Our results demonstrate that in mechanically integrated epithelial sheets, cell contractility can be transmitted through multiple cells and focused by substrate topography to affect a behavioral response at distant sites.

[Establishment of goat limbal stem cell strain expressing Venus fluorescent protein and construction of limbal epithelial sheets].

PubMed

Yin, Jiqing; Liu, Wenqiang; Liu, Chao; Zhao, Guimin; Zhang, Yihua; Liu, Weishuai; Hua, Jinlian; Dou, Zhongying; Lei, Anmin

2010-12-01

The integrity and transparency of cornea plays a key role in vision. Limbal Stem Cells (LSCs) are precursors of cornea, which are responsible for self-renewal and replenishing corneal epithelium. Though it is successful to cell replacement therapy for impairing ocular surface by Limbal Stem Cell Transplantation (LSCT), the mechanism of renew is unclear after LSCT. To real time follow-up the migration and differentiation of corneal transplanted epithelial cells after transplanting, we transfected venus (a fluorescent protein gene) into goat LSCs, selected with G418 and established a stable transfected cell line, named GLSC-V. These cells showed green fluorescence, and which could maintain for at least 3 months. GLSC-V also were positive for anti-P63 and anti-Integrinbeta1 antibody by immunofluorescent staining. We founded neither GLSC-V nor GLSCs expressed keratin3 (k3) and keratinl2 (k12). However, GLSC-V had higher levels in expression of p63, pcna and venus compared with GLSCs. Further, we cultivated the cells on denude amniotic membrane to construct tissue engineered fluorescent corneal epithelial sheets. Histology and HE staining showed that the constructed fluorescent corneal epithelial sheets consisted of 5-6 layers of epithelium. Only the lowest basal cells of fluorescent corneal epithelial sheets expressed P63 analyzed by immunofluorescence, but not superficial epithelial cells. These results showed that our constructed fluorescent corneal epithelial sheets were similar to the normal corneal epithelium in structure and morphology. This demonstrated that they could be transplanted for patents with corneal impair, also may provide a foundation for the study on the mechanisms of corneal epithelial cell regeneration after LSCT.

Apical Cyst Theory: a Missing Link

PubMed Central

Huang, George T.-J.

2012-01-01

Introduction The mechanism of the formation of apical cyst has been elusive. Several theories have long been proposed and discussed speculating how an apical cyst is developed and formed in the jaw bone resulting from endododontic infection. Two popular theories are the nutritional deficiency theory and the abscess theory. The nutritional deficiency theory assumes that the over proliferated epithelial cells will form a ball mass such that the cells in the center of the mass will be deprived of nutrition. The abscess theory postulates that when an abscess cavity is formed in connective tissue, epithelial cells proliferate and line the preexisting cavity because of their inherent tendency to cover exposed connective tissue surfaces. Based on the nature of epithelial cells and the epithelium, nutritional theory is a fairy tale, while abscess theory at best just indicates that abscess may be one of the factors that allows the stratified epithelium to form but not to explain a mechanism that makes the cyst to form. The hypothesis Apical cyst formation is the result of proliferation of resting epithelial cells, due to inflammation, to a sufficient number such that they are able to form a polarized and stratified epithelial lining against dead tissues or foreign materials. These stratified epithelial lining expands along the dead tissue or foreign materials and eventually wrap around them as a spherical sac, i.e. a cyst. The space in the sac is considered the external environment separating the internal (tissue) environment – the natural function of epithelium. Evaluation of the hypothesis This theory may be tested by introducing a biodegradable device able to slowly release epithelial cell mitogens in an in vivo environment implanted with epithelial cells next to a foreign object. This will allow the cells to continuously proliferate which may form a cystic sac wrapping around the foreign object. PMID:25346864

Epithelial PIK3R1 (p85) and TP53 Regulate Survivin Expression during Adaptation to Ileocecal Resection.

PubMed

Cohran, Valeria; Managlia, Elizabeth; Bradford, Emily M; Goretsky, Tatiana; Li, Ting; Katzman, Rebecca B; Cheresh, Paul; Brown, Jeffrey B; Hawkins, Jennifer; Liu, Shirley X L; De Plaen, Isabelle G; Weitkamp, Jörn-Hendrik; Helmrath, Michael; Zhang, Zheng; Barrett, Terrence A

2016-07-01

Intestinal adaptation to small-bowel resection (SBR) after necrotizing enterocolitis expands absorptive surface areas and promotes enteral autonomy. Survivin increases proliferation and blunts apoptosis. The current study examines survivin in intestinal epithelial cells after ileocecal resection. Wild-type and epithelial Pik3r1 (p85α)-deficient mice underwent sham surgery or 30% resection. RNA and protein were isolated from small bowel to determine levels of β-catenin target gene expression, activated caspase-3, survivin, p85α, and Trp53. Healthy and post-resection human infant small-bowel sections were analyzed for survivin, Ki-67, and TP53 by immunohistochemistry. Five days after ileocecal resection, epithelial levels of survivin increased relative to sham-operated on mice, which correlated with reduced cleaved caspase-3, p85α, and Trp53. At baseline, p85α-deficient intestinal epithelial cells had less Trp53 and more survivin, and relative responses to resection were blunted compared with wild-type. In infant small bowel, survivin in transit amplifying cells increased 71% after SBR. Resection increased proliferation and decreased numbers of TP53-positive epithelial cells. Data suggest that ileocecal resection reduces p85α, which lowers TP53 activation and releases survivin promoter repression. The subsequent increase in survivin among transit amplifying cells promotes epithelial cell proliferation and lengthens crypts. These findings suggest that SBR reduces p85α and TP53, which increases survivin and intestinal epithelial cell expansion during therapeutic adaptation in patients with short bowel syndrome. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Development of a conjunctival tissue substitute on the basis of plastic compressed collagen.

PubMed

Drechsler, C C; Kunze, A; Kureshi, A; Grobe, G; Reichl, S; Geerling, G; Daniels, J T; Schrader, S

2017-03-01

Ocular surface disorders, such as pterygium, cicatricial pemphigoid and external disruptions, can cause severe inflammation, scarring, fornix shortening as well as ankyloblepharon. Current treatments do not resolve these conditions sufficiently. The aim of this study was to evaluate clinical applicability and suitability of plastic compressed collagen to serve as a substrate for the expansion of human conjunctival epithelial cells in order to develop an epithelialized conjunctival substitute for fornix reconstruction. Human conjunctival epithelial cells were expanded on plastic compressed collagen gels. Epithelial cell characteristics were evaluated by haematoxylin and eosin staining, electron microscopy and cytokeratin expression. The expression of putative epithelial progenitor cell markers p63α, ABCG2 and CK15 was assessed by immunostaining. The proliferative capacity and clonal growth of the cells was evaluated before (P0) and after expansion (P1) on the plastic compressed collagen gels by colony forming efficiency assay. The potential clinical applicability of this gel substitutes was evaluated by assessment of their biomechanical properties as well as their surgical handling. Human conjunctival epithelial cells cultured on plastic and plastic compressed collagen gels formed a confluent cell layer and expressed CK19. The cells showed expression of the putative epithelial progenitor cell markers p63α, ABCG2 and CK15 and sustained colony forming ability. The compressed collagen gels showed a high ultimate tensile strength and elasticity and the surgical handling of gels was comparable to amniotic membrane. An epithelialized conjunctival tissue construct on the basis of compressed collagen might therefore be a promising alternative bioartificial tissue substitute for conjunctival reconstruction. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

NADPH-diaphorase activity and NO synthase expression in the olfactory epithelium of the bovine.

PubMed

Wenisch, S; Arnhold, S

2010-06-01

NADPH-diaphorase (NADPH-d) staining of the bovine olfactory epithelium was compared with the immunohistochemical localization of nitric oxide synthase (NOS), soluble guanylyl cyclase, and cGMP (cyclic guanosine 3',5'-monophosphate). Out of the three isoforms, only the inducible NOS (NOS-II) was found at the epithelial surface correlating with the strong labelling for NADPH-d. In contrast, light diaphorase staining associated with deeper epithelial regions did not coincide with any NOS immunoreactivity. As there is overlapping expression of NOS-II, soluble guanylyl cyclase and cGMP at the luminal surface morphologically occupied by dendritic knobs of olfactory receptor neurons and microvillar endings of supporting cells, the nitric oxide (NO)/cGMP pathway is likely to be involved in modulating the odour signals during olfactory transduction.

A surface-charge study on cellular-uptake behavior of F3-peptide-conjugated iron oxide nanoparticles.

PubMed

Zhang, Yu; Yang, Mo; Park, Ji-Ho; Singelyn, Jennifer; Ma, Huiqing; Sailor, Michael J; Ruoslahti, Erkki; Ozkan, Mihrimah; Ozkan, Cengiz

2009-09-01

Surface-charge measurements of mammalian cells in terms of Zeta potential are demonstrated as a useful biological characteristic in identifying cellular interactions with specific nanomaterials. A theoretical model of the changes in Zeta potential of cells after incubation with nanoparticles is established to predict the possible patterns of Zeta-potential change to reveal the binding and internalization effects. The experimental results show a distinct pattern of Zeta-potential change that allows the discrimination of human normal breast epithelial cells (MCF-10A) from human cancer breast epithelial cells (MCF-7) when the cells are incubated with dextran coated iron oxide nanoparticles that contain tumor-homing F3 peptides, where the tumor-homing F3 peptide specifically bound to nucleolin receptors that are overexpressed in cancer breast cells.

Epithelial-specific A2B adenosine receptor signaling protects the colonic epithelial barrier during acute colitis

PubMed Central

Aherne, CM; Saeedi, B; Collins, CB; Masterson, JC; McNamee, EN; Perrenoud, L; Rapp, CR; Curtis, VF; Bayless, A; Fletcher, A; Glover, LE; Evans, CM; Jedlicka, P; Furuta, GT; de Zoeten, EF; Colgan, SP; Eltzschig, HK

2015-01-01

Central to inflammatory bowel disease (IBD) pathogenesis is loss of mucosal barrier function. Emerging evidence implicates extracellular adenosine signaling in attenuating mucosal inflammation. We hypothesized that adenosine-mediated protection from intestinal barrier dysfunction involves tissue-specific signaling through the A2B adenosine receptor (Adora2b) at the intestinal mucosal surface. To address this hypothesis, we combined pharmacologic studies and studies in mice with global or tissue-specific deletion of the Adora2b receptor. Adora2b−/− mice experienced a significantly heightened severity of colitis, associated with a more acute onset of disease and loss of intestinal epithelial barrier function. Comparison of mice with Adora2b deletion on vascular endothelial cells (Adora2bfl/flVeCadCre+) or intestinal epithelia (Adora2bfl/flVillinCre+) revealed a selective role for epithelial Adora2b signaling in attenuating colonic inflammation. In vitro studies with Adora2b knockdown in intestinal epithelial cultures or pharmacologic studies highlighted Adora2b-driven phosphorylation of vasodilator-stimulated phosphoprotein (VASP) as a specific barrier repair response. Similarly, in vivo studies in genetic mouse models or treatment studies with an Adora2b agonist (BAY 60-6583) recapitulate these findings. Taken together, our results suggest that intestinal epithelial Adora2b signaling provides protection during intestinal inflammation via enhancing mucosal barrier responses. PMID:25850656

Identifying the cellular mechanisms of symbiont-induced epithelial morphogenesis in the squid-vibrio association

PubMed Central

Koropatnick, Tanya; Goodson, Michael S.; Heath-Heckman, Elizabeth A. C.; McFall-Ngai, Margaret

2014-01-01

The symbiotic association between the Hawaiian bobtail squid Euprymna scolopes and the luminous marine bacterium Vibrio fischeri provides a unique opportunity to study epithelial morphogenesis. Shortly after hatching, the squid host harvests bacteria from the seawater using currents created by two elaborate fields of ciliated epithelia on the surface of the juvenile light organ. After light organ colonization, the symbiont population signals the gradual loss of the ciliated epithelia through apoptosis of the cells, which culminates in the complete regression of these tissues. Whereas aspects of this process have been studied at the morphological, biochemical and molecular levels, no in-depth analysis of the cellular events has been reported. Here we describe the cellular structure of the epithelial field and present evidence that the symbiosis-induced regression occurs in two steps. Using confocal microscopic analyses, we observed an initial epithelial remodeling, which serves to disable the function of the harvesting apparatus, followed by a protracted regression involving actin rearrangements and epithelial cell extrusion. We identified a metal-dependent gelatinolytic activity in the symbiont-induced morphogenic epithelial fields, suggesting the involvement of Zn-dependent matrix metalloproteinase(s) (MMP) in light organ morphogenesis. These data show that the bacterial symbionts not only induce apoptosis of the field, but also change the form, function and biochemistry of the cells as part of the morphogenic program. PMID:24648207

Histologically proven epithelial ingrowth in failed Descemet stripping automated endothelial keratoplasty (DSAEK) managed by repeat DSAEK

PubMed Central

Ghosh, Saurabh; Bonshek, Richard; Morgan, Stephen J

2013-01-01

Purpose To report a case of corneal graft failure due to epithelial ingrowth after an uneventful combined Descemet stripping automated endothelial keratoplasty (DSAEK) and phacoemulsification cataract surgery with intraocular lens implant treated successfully with a repeat DSAEK. Methods A 77-year-old male patient underwent combined DSAEK and phacoemulsification with intraocular lens implant implantation for Fuchs’ endothelial dystrophy plus cataract in the right eye. The donor cornea was cut on the Moria ALTK system and introduced using a suture pull-through technique. After an episode of endothelial rejection, the graft failed, with signs suggesting epithelial ingrowth. It was stripped from the host cornea using a Descemet’s membrane stripper, and a Simcoe irrigation-aspiration cannula was used to remove all traces of interface material. The excised lenticule was examined histologically using a hematoxylin and eosin stain. Result The patient regained and maintained excellent visual acuity with no sign of recurrence of epithelial ingrowth. Histopathological evaluation of the donor tissue of the first graft showed epithelial ingrowth on the stromal surface of the graft and very few endothelial cells, in keeping with the diagnosis of graft failure. Conclusion Epithelial ingrowth is a possible cause of endothelial graft failure, but histologically proven cases are rare. Surgical intervention can achieve successful clearance, with the potential for cure and an excellent outcome. PMID:23754868

Identifying the cellular mechanisms of symbiont-induced epithelial morphogenesis in the squid-Vibrio association.

PubMed

Koropatnick, Tanya; Goodson, Michael S; Heath-Heckman, Elizabeth A C; McFall-Ngai, Margaret

2014-02-01

The symbiotic association between the Hawaiian bobtail squid Euprymna scolopes and the luminous marine bacterium Vibrio fischeri provides a unique opportunity to study epithelial morphogenesis. Shortly after hatching, the squid host harvests bacteria from the seawater using currents created by two elaborate fields of ciliated epithelia on the surface of the juvenile light organ. After light organ colonization, the symbiont population signals the gradual loss of the ciliated epithelia through apoptosis of the cells, which culminates in the complete regression of these tissues. Whereas aspects of this process have been studied at the morphological, biochemical, and molecular levels, no in-depth analysis of the cellular events has been reported. Here we describe the cellular structure of the epithelial field and present evidence that the symbiosis-induced regression occurs in two steps. Using confocal microscopic analyses, we observed an initial epithelial remodeling, which serves to disable the function of the harvesting apparatus, followed by a protracted regression involving actin rearrangements and epithelial cell extrusion. We identified a metal-dependent gelatinolytic activity in the symbiont-induced morphogenic epithelial fields, suggesting the involvement of Zn-dependent matrix metalloproteinase(s) (MMP) in light organ morphogenesis. These data show that the bacterial symbionts not only induce apoptosis of the field, but also change the form, function, and biochemistry of the cells as part of the morphogenic program.

Dry eye symptoms are increased in mice deficient in phospholipid transfer protein (PLTP).

PubMed

Setälä, Niko L; Metso, Jari; Jauhiainen, Matti; Sajantila, Antti; Holopainen, Juha M

2011-05-01

In the tear fluid the outermost part facing the tear-air interface is composed of lipids preventing evaporation of the tears. Phospholipid transfer protein (PLTP) mediates phospholipid transfer processes between serum lipoproteins and is also a normal component of human tears. To study whether PLTP plays any functional role in tear fluid we investigated PLTP-deficient mice, applying functional and morphologic analyses under normal housing and experimentally induced dry eye conditions. Aqueous tear fluid production, corneal epithelial morphology, barrier function, and occludin expression were assessed. In mice with a full deficiency of functional PLTP enhanced corneal epithelial damage, increased corneal permeability to carboxyfluorescein, and decreased corneal epithelial occludin expression were shown. These pathologic signs were worsened by experimentally induced dry eye both in wild-type and PLTP knock-out mice. Deficiency in the production of tear PLTP in mice is accompanied by corneal epithelial damage, a feature that is typical in human dry eye syndrome (DES). To complement animal experiments we collected tear fluid from human dry eye patients as well as healthy control subjects. Increased tear fluid PLTP activity was observed among DES patients. In conclusion, the presence of PLTP in tear fluid appears to be essential for maintaining a healthy and functional ocular surface. Increased PLTP activity in human tear fluid in DES patients suggests an ocular surface protective role for this lipid transfer protein. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Impairment of vascularization of the surface covering epithelium induces ischemia and promotes malignization: a new hypothesis of a possible mechanism of cancer pathogenesis.

PubMed

Karseladze, A I

2015-06-01

To study the peculiarities of vascularization at the stromal-epithelial interface in different types of epithelia and their alterations in precancerous lesions. Peritumoral tissues of 310 patients, tissues of 180 healthy persons and of 50 human embryos and fetuses were used. Traditional histological as well as immunohistochemical methods have been used. The study reveals that the occurrence of blood capillaries in surface squamous epithelium is an ordinary event, both in healthy persons and in peritumoral regions of the patients with squamous cell carcinoma. Glandular epithelial coverings, as well as transitional epithelium, do not contain blood vessels. In squamous epithelium, only basal cells are in contact with the membrane and underlying stroma, the cells of the upper layer receiving nutrients through diffusion. Thus, the cells of squamous epithelium are more vulnerable to blood deficiency, since for instance in the pseudo-multilayered respiratory epithelium each cell is attached directly to the basal membrane and has more ample access to the blood supply. Metaplastic squamous epithelium has a markedly reduced vascularization and seems to be more sensitive to carcinogenic stimuli. High-grade dysplastic squamous epithelium and carcinoma in situ do not contain blood vessels. The process of redistribution of vascular network occurring at the interface of epithelial-stromal frontier plays an important role in maintaining the adequate metabolism of cells including those of epithelial covering. Impairment of this mechanism most probably promotes precancerous alterations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harkema, J.R.; Hotchkiss, J.A.; Griffith, W.C.

The present study was designed to examine the effects of long-term ozone exposure on nasal epithelia and intraepithelial mucosubstances (IM) throughout the nasal airways of F344/N rats. Animals were exposed to 0 (controls). 0. 12. 0.5, or 1.0 ppm ozone. 6 h/day, 5 days/wk. for 20 mo. Rats were killed 1 wk after the end of the exposure. and nasal tissues were processed for light and electron microscopy. Standard morphometric techniques were used to determine epithelial cell densities and the amounts of IM in the surface epithelium lining the nasal airways. No mucous cells or IM were present in themore » epithelia lining the nasal lateral meatus and maxillary sinus of rats exposed to 0 or 0.12 ppm ozone. In contrast, rats exposed to 0.5 or 1.0 ppm ozone had marked mucous cell metaplasia (MCM) with numerous mucous cells and conspicuous amounts of IM in the surface epithelium lining these upper airways. Ozone-induced increases in total epithelial cells (i.e., epithelial hyperplasia) were present only in rats exposed to 1.0 ppm. The results of this study indicate that rats chronically exposed to 1.0 or 0.5 ppm, but not 0. 121 ppm. ozone can develop marked MCM with significant increases in IM in both proximal and distal nasal airways. The epithelial chances observed throughout the nasal passages of ozone-exposed rats may be adaptive responses in an attempt to protect the upper and lower respiratory tract from further ozone-induced injury.« less

Vocal Fold Epithelial Response to Luminal Osmotic Perturbation

ERIC Educational Resources Information Center

Sivasankar, Mahalakshmi; Fisher, Kimberly V.

2007-01-01

Purpose: Dry-air challenges increase the osmolarity of fluid lining the luminal surface of the proximal airway. The homeostasis of surface fluid is thought to be essential for voice production and laryngeal defense. Therefore, the authors hypothesized that viable vocal fold epithelium would generate a water flux to reduce an osmotic challenge (150…

The effect of surface functionality on cellular trafficking of dendrimers.

PubMed

Perumal, Omathanu P; Inapagolla, Rajyalakshmi; Kannan, Sujatha; Kannan, Rangaramanujam M

2008-01-01

Dendrimers are an emerging group of nanostructured, polymeric biomaterials that have potential as non-viral vehicles for delivering drugs and genetic material to intracellular targets. They have a high charge density with tunable surface functional groups, which can alter the local environment and influence cellular interactions. This can have a significant impact on the intracellular trafficking of dendrimer-based nanodevices. With the help of flow cytometry, fluorescence microscopy, and by using specific inhibitors, the influence of surface functionality on their uptake in A549 lung epithelial cells, and subsequent intracellular distribution was investigated. In this paper, we have shown that even though all the dendrimers are taken up by fluid-phase endocytosis, significant differences in uptake mechanisms exist. Anionic dendrimers appear to be mainly taken up by caveolae mediated endocytosis in A549 lung epithelial cells, while cationic and neutral dendrimers appear to be taken in by a non-clathrin, non-caveolae mediated mechanism that may be by electrostatic interactions or other non-specific fluid-phase endocytosis. These findings open up new possibilities of targeting therapeutic agents to specific cell organelles based on surface charge.

On physical changes on surface of human cervical epithelial cells during cancer transformations

NASA Astrophysics Data System (ADS)

Sokolov, Igor; Dokukin, Maxim; Guz, Nataliia; Woodworth, Craig

2013-03-01

Physical changes of the cell surface of cells during transformation from normal to cancerous state are rather poorly studied. Here we describe our recent studies of such changes done on human cervical epithelial cells during their transformation from normal through infected with human papillomavirus type-16 (HPV-16), immortalized (precancerous), to cancerous cells. The changes were studied with the help of atomic force microscopy (AFM) and through the measurement of physical adhesion of fluorescent silica beads to the cell surface. Based on the adhesion experiments, we clearly see the difference in nonspecific adhesion which occurs at the stage of immortalization of cells, precancerous cells. The analysis done with the help of AFM shows that the difference observed comes presumably from the alteration of the cellular ``brush,'' a layer that surrounds cells and which consists of mostly microvilli, microridges, and glycocalyx. Further AFM analysis reveals the emergence of fractal scaling behavior on the surface of cells when normal cells turn into cancerous. The possible causes and potential significance of these observations will be discussed.

Preparation of Caco-2 cell sheets using plasma polymerised acrylic acid as a weak boundary layer.

PubMed

Majani, Ruby; Zelzer, Mischa; Gadegaard, Nikolaj; Rose, Felicity R; Alexander, Morgan R

2010-09-01

The use of cell sheets for tissue engineering applications has considerable advantages over single cell seeding techniques. So far, only thermoresponsive surfaces have been used to manufacture cell sheets without chemically disrupting the cell-surface interactions. Here, we present a new and facile technique to prepare sheets of epithelial cells using plasma polymerised acrylic acid films. The cell sheets are harvested by gentle agitation of the media without the need of any additional external stimulus. We demonstrate that the plasma polymer deposition conditions affect the viability and metabolic activity of the cells in the sheet and relate these effects to the different surface properties of the plasma polymerised acrylic acid films. Based on surface analysis data, a first attempt is made to explain the mechanism behind the cell sheet formation. The advantage of the epithelial cell sheets generated here over single cell suspensions to seed a PLGA scaffold is presented. The scaffold itself, prepared using a mould fabricated via photolithography, exhibits a unique architecture that mimics closely the dimensions of the native tissue (mouse intestine). Copyright 2010 Elsevier Ltd. All rights reserved.

Tight junctions in inflammatory bowel diseases and inflammatory bowel disease associated colorectal cancer

PubMed Central

Landy, Jonathan; Ronde, Emma; English, Nick; Clark, Sue K; Hart, Ailsa L; Knight, Stella C; Ciclitira, Paul J; Al-Hassi, Hafid Omar

2016-01-01

Inflammatory bowel diseases are characterised by inflammation that compromises the integrity of the epithelial barrier. The intestinal epithelium is not only a static barrier but has evolved complex mechanisms to control and regulate bacterial interactions with the mucosal surface. Apical tight junction proteins are critical in the maintenance of epithelial barrier function and control of paracellular permeability. The characterisation of alterations in tight junction proteins as key players in epithelial barrier function in inflammatory bowel diseases is rapidly enhancing our understanding of critical mechanisms in disease pathogenesis as well as novel therapeutic opportunities. Here we give an overview of recent literature focusing on the role of tight junction proteins, in particular claudins, in inflammatory bowel diseases and inflammatory bowel disease associated colorectal cancer. PMID:27003989

The Role of Cell Surface Architecture of Lactobacilli in Host-Microbe Interactions in the Gastrointestinal Tract

PubMed Central

Altermann, Eric; Anderson, Rachel C.; McNabb, Warren C.; Moughan, Paul J.; Roy, Nicole C.

2013-01-01

Lactobacillus species can exert health promoting effects in the gastrointestinal tract (GIT) through many mechanisms, which include pathogen inhibition, maintenance of microbial balance, immunomodulation, and enhancement of the epithelial barrier function. Different species of the genus Lactobacillus can evoke different responses in the host, and not all strains of the same species can be considered beneficial. Strain variations may be related to diversity of the cell surface architecture of lactobacilli and the bacteria's ability to express certain surface components or secrete specific compounds in response to the host environment. Lactobacilli are known to modify their surface structures in response to stress factors such as bile and low pH, and these adaptations may help their survival in the face of harsh environmental conditions encountered in the GIT. In recent years, multiple cell surface-associated molecules have been implicated in the adherence of lactobacilli to the GIT lining, immunomodulation, and protective effects on intestinal epithelial barrier function. Identification of the relevant bacterial ligands and their host receptors is imperative for a better understanding of the mechanisms through which lactobacilli exert their beneficial effects on human health. PMID:23576850

Automated segmentation of oral mucosa from wide-field OCT images (Conference Presentation)

NASA Astrophysics Data System (ADS)

Goldan, Ryan N.; Lee, Anthony M. D.; Cahill, Lucas; Liu, Kelly; MacAulay, Calum; Poh, Catherine F.; Lane, Pierre

2016-03-01

Optical Coherence Tomography (OCT) can discriminate morphological tissue features important for oral cancer detection such as the presence or absence of basement membrane and epithelial thickness. We previously reported an OCT system employing a rotary-pullback catheter capable of in vivo, rapid, wide-field (up to 90 x 2.5mm2) imaging in the oral cavity. Due to the size and complexity of these OCT data sets, rapid automated image processing software that immediately displays important tissue features is required to facilitate prompt bed-side clinical decisions. We present an automated segmentation algorithm capable of detecting the epithelial surface and basement membrane in 3D OCT images of the oral cavity. The algorithm was trained using volumetric OCT data acquired in vivo from a variety of tissue types and histology-confirmed pathologies spanning normal through cancer (8 sites, 21 patients). The algorithm was validated using a second dataset of similar size and tissue diversity. We demonstrate application of the algorithm to an entire OCT volume to map epithelial thickness, and detection of the basement membrane, over the tissue surface. These maps may be clinically useful for delineating pre-surgical tumor margins, or for biopsy site guidance.

Psoriasin, a novel anti-Candida albicans adhesin.

PubMed

Brauner, Annelie; Alvendal, Cathrin; Chromek, Milan; Stopsack, Konrad H; Ehrström, Sophia; Schröder, Jens M; Bohm-Starke, Nina

2018-05-07

Candida albicans belongs to the normal microbial flora on epithelial surfaces of humans. However, under certain, still not fully understood conditions, it can become pathogenic and cause a spectrum of diseases, from local infections to life-threatening septicemia. We investigated a panel of antimicrobial proteins and peptides (AMPs), potentially involved in mucosal immunity against this pathogen. Out of six studied AMPs, psoriasin was most up-regulated during a mucosal infection, an acute episode of recurrent Candida vulvovaginitis, although candidacidal activity has not been demonstrated. We here show that psoriasin binds to β-glucan, a basic component of the C. albicans cell wall, and thereby inhibits adhesion of the pathogen to surfaces and increases IL-8 production by mucosal epithelial cells. In conclusion, we show a novel mechanism of action of psoriasin. By inhibiting C. albicans adhesion and by enhancing cytokine production, psoriasin contributes to the immune response against C. albicans. The antimicrobial peptide psoriasin is highly up-regulated during a local mucosal infection, Candida albicans vulvovaginitis. Psoriasin binds to β-glucan in the Candida albicans cell wall and thereby inhibits adhesion of the pathogen. Binding of psoriasin to Candida albicans induces an immune response by mucosal epithelial cells.

Toll-like receptors as novel therapeutic targets for ovarian cancer.

PubMed

Muccioli, Maria; Sprague, Leslee; Nandigam, Harika; Pate, Michelle; Benencia, Fabian

2012-01-01

Ovarian cancer (OC) is an aggressive disease that affects approximately 1 in 70 women and has a poor prognosis (<50%, 5-year survival rate), in part because it is often diagnosed at a late stage. There are three main types of OC: neoplasms of surface epithelial, germ cell, or stromal origin, with surface epithelial tumors comprising about 80% of all OCs. In addition to improving diagnostics, it is necessary to develop more effective treatments for epithelial-origin OC. Here, we describe the paradoxical roles of toll-like receptor (TLR) signaling in the progression of cancer and discuss how its modulation may result in decreased tumor growth and metastasis via the attenuation of proangiogenic cytokines and potentiation of proapoptotic factors. In particular, it has been found that TLR activity can behave like a "double-edged sword", as its signaling pathways have been implicated as having both tumor-suppressive and tumor-promoting effects. With particular emphasis on OC, we discuss the need to consider the signaling details of TLRs and associated proteins in the multiple cell types present in the tumor milieu to achieve safe and effective design of TLR-based cancer therapies.

Toll-Like Receptors as Novel Therapeutic Targets for Ovarian Cancer

PubMed Central

Muccioli, Maria; Sprague, Leslee; Nandigam, Harika; Pate, Michelle; Benencia, Fabian

2012-01-01

Ovarian cancer (OC) is an aggressive disease that affects approximately 1 in 70 women and has a poor prognosis (<50%, 5-year survival rate), in part because it is often diagnosed at a late stage. There are three main types of OC: neoplasms of surface epithelial, germ cell, or stromal origin, with surface epithelial tumors comprising about 80% of all OCs. In addition to improving diagnostics, it is necessary to develop more effective treatments for epithelial-origin OC. Here, we describe the paradoxical roles of toll-like receptor (TLR) signaling in the progression of cancer and discuss how its modulation may result in decreased tumor growth and metastasis via the attenuation of proangiogenic cytokines and potentiation of proapoptotic factors. In particular, it has been found that TLR activity can behave like a “double-edged sword”, as its signaling pathways have been implicated as having both tumor-suppressive and tumor-promoting effects. With particular emphasis on OC, we discuss the need to consider the signaling details of TLRs and associated proteins in the multiple cell types present in the tumor milieu to achieve safe and effective design of TLR-based cancer therapies. PMID:22530148

Dystroglycan loss disrupts polarity and beta-casein induction inmammary epithelial cells by perturbing laminin anchoring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weir, M. Lynn; Oppizzi, Maria Luisa; Henry, Michael D.

2006-02-17

Precise contact between epithelial cells and their underlying basement membrane is critical to the maintenance of tissue architecture and function. To understand the role that the laminin receptor dystroglycan (DG) plays in these processes, we assayed cell responses to laminin-111 following conditional ablation of DG expression in cultured mammary epithelial cells (MECs). Strikingly, DG loss disrupted laminin-111-induced polarity and {beta}-casein production, and abolished laminin assembly at the step of laminin binding to the cell surface. DG re-expression restored these deficiencies. Investigations of mechanism revealed that DG cytoplasmic sequences were not necessary for laminin assembly and signaling, and only when themore » entire mucin domain of extracellular DG was deleted did laminin assembly not occur. These results demonstrate that DG is essential as a laminin-111 co-receptor in MECs that functions by mediating laminin anchoring to the cell surface, a process that allows laminin polymerization, tissue polarity, and {beta}-casein induction. The observed loss of laminin-111 assembly and signaling in DG-/-MECs provides insights into the signaling changes occurring in breast carcinomas and other cancers, where DG's laminin-binding function is frequently defective.« less

Helicobacter pylori perturbs iron trafficking in the epithelium to grow on the cell surface.

PubMed

Tan, Shumin; Noto, Jennifer M; Romero-Gallo, Judith; Peek, Richard M; Amieva, Manuel R

2011-05-01

Helicobacter pylori (Hp) injects the CagA effector protein into host epithelial cells and induces growth factor-like signaling, perturbs cell-cell junctions, and alters host cell polarity. This enables Hp to grow as microcolonies adhered to the host cell surface even in conditions that do not support growth of free-swimming bacteria. We hypothesized that CagA alters host cell physiology to allow Hp to obtain specific nutrients from or across the epithelial barrier. Using a polarized epithelium model system, we find that isogenic ΔcagA mutants are defective in cell surface microcolony formation, but exogenous addition of iron to the apical medium partially rescues this defect, suggesting that one of CagA's effects on host cells is to facilitate iron acquisition from the host. Hp adhered to the apical epithelial surface increase basolateral uptake of transferrin and induce its transcytosis in a CagA-dependent manner. Both CagA and VacA contribute to the perturbation of transferrin recycling, since VacA is involved in apical mislocalization of the transferrin receptor to sites of bacterial attachment. To determine if the transferrin recycling pathway is involved in Hp colonization of the cell surface, we silenced transferrin receptor expression during infection. This resulted in a reduced ability of Hp to colonize the polarized epithelium. To test whether CagA is important in promoting iron acquisition in vivo, we compared colonization of Hp in iron-replete vs. iron-deficient Mongolian gerbils. While wild type Hp and ΔcagA mutants colonized iron-replete gerbils at similar levels, ΔcagA mutants are markedly impaired in colonizing iron-deficient gerbils. Our study indicates that CagA and VacA act in concert to usurp the polarized process of host cell iron uptake, allowing Hp to use the cell surface as a replicative niche.

Helicobacter pylori Perturbs Iron Trafficking in the Epithelium to Grow on the Cell Surface

PubMed Central

Tan, Shumin; Noto, Jennifer M.; Romero-Gallo, Judith; Peek, Richard M.; Amieva, Manuel R.

2011-01-01

Helicobacter pylori (Hp) injects the CagA effector protein into host epithelial cells and induces growth factor-like signaling, perturbs cell-cell junctions, and alters host cell polarity. This enables Hp to grow as microcolonies adhered to the host cell surface even in conditions that do not support growth of free-swimming bacteria. We hypothesized that CagA alters host cell physiology to allow Hp to obtain specific nutrients from or across the epithelial barrier. Using a polarized epithelium model system, we find that isogenic ΔcagA mutants are defective in cell surface microcolony formation, but exogenous addition of iron to the apical medium partially rescues this defect, suggesting that one of CagA's effects on host cells is to facilitate iron acquisition from the host. Hp adhered to the apical epithelial surface increase basolateral uptake of transferrin and induce its transcytosis in a CagA-dependent manner. Both CagA and VacA contribute to the perturbation of transferrin recycling, since VacA is involved in apical mislocalization of the transferrin receptor to sites of bacterial attachment. To determine if the transferrin recycling pathway is involved in Hp colonization of the cell surface, we silenced transferrin receptor expression during infection. This resulted in a reduced ability of Hp to colonize the polarized epithelium. To test whether CagA is important in promoting iron acquisition in vivo, we compared colonization of Hp in iron-replete vs. iron-deficient Mongolian gerbils. While wild type Hp and ΔcagA mutants colonized iron-replete gerbils at similar levels, ΔcagA mutants are markedly impaired in colonizing iron-deficient gerbils. Our study indicates that CagA and VacA act in concert to usurp the polarized process of host cell iron uptake, allowing Hp to use the cell surface as a replicative niche. PMID:21589900

Lacritin and Other New Proteins of the Lacrimal Functional Unit

PubMed Central

McKown, Robert L.; Wang, Ningning; Raab, Ronald W.; Karnati, Roy; Zhang, Yinghui; Williams, Patricia B.; Laurie, Gordon W.

2009-01-01

The lacrimal functional unit (LFU) is defined by the 2007 International Dry Eye WorkShop as ‘an integrated system comprising the lacrimal glands, ocular surface (cornea, conjunctiva and meibomian glands) and lids, and the sensory and motor nerves that connect them’. The LFU maintains a healthy ocular surface primarily through a properly functioning tear film that provides protection, lubrication, and an environment for corneal epithelial cell renewal. LFU cells express thousands of proteins. Over two hundred new LFU proteins have been discovered in the last decade. Lacritin is a new LFU-specific growth factor in human tears that flows through ducts to target corneal epithelial cells on the ocular surface. When applied topically in rabbits, lacritin appears to increase the volume of basal tear secretion. Lacritin is one of only a handful of tear proteins preliminarily reported to be downregulated in blepharitis and in two dry eye syndromes. Computational analysis predicts an ordered C-terminal domain that binds the corneal epithelial cell surface proteoglycan syndecan-1 (SDC1) and is required for lacritin’s low nanomolar mitogenic activity. The lacritin binding site on the N-terminus of SDC1 is exposed by heparanase. Heparanase is constitutively expressed by the corneal epithelium and appears to be a normal constituent of tears. Binding triggers rapid signaling to downstream NFAT and mTOR. A wealth of other new proteins, originally designated as hypothetical when first identified by genomic sequencing, are expressed by the human LFU including: ALS2CL, ARHGEF19, KIAA1109, PLXNA1, POLG, WIPI1 and ZMIZ2. Their demonstrated or implied roles in human genetic disease or basic cellular functions are fuel for new investigation. Addressing topical areas in ocular surface physiology with new LFU proteins may reveal interesting new biological mechanisms and help get to the heart of ocular surface dysfunction. PMID:18840430

Anti-mouse CD52 monoclonal antibody ameliorates intestinal epithelial barrier function in interleukin-10 knockout mice with spontaneous chronic colitis.

PubMed

Wang, Honggang; Dong, Jianning; Shi, Peiliang; Liu, Jianhui; Zuo, Lugen; Li, Yi; Gong, Jianfeng; Gu, Lili; Zhao, Jie; Zhang, Liang; Zhang, Wei; Zhu, Weiming; Li, Ning; Li, Jieshou

2015-02-01

Intestinal inflammation causes tight junction changes and death of epithelial cells, and plays an important role in the development of Crohn's disease (CD). CD52 monoclonal antibody (CD52 mAb) directly targets the cell surface CD52 and is effective in depleting mature lymphocytes by cytolytic effects in vivo, leading to long-lasting changes in adaptive immunity. The aim of this study was to investigate the therapeutic effect of CD52 mAb on epithelial barrier function in animal models of IBD. Interleukin-10 knockout mice (IL-10(-/-) ) of 16 weeks with established colitis were treated with CD52 mAb once a week for 2 weeks. Severity of colitis, CD4(+) lymphocytes and cytokines in the lamina propria, epithelial expression of tight junction proteins, morphology of tight junctions, tumour necrosis factor-α (TNF-α)/TNF receptor 2 (TNFR2) mRNA expression, myosin light chain kinase (MLCK) expression and activity, as well as epithelial apoptosis in proximal colon were measured at the end of the experiment. CD52 mAb treatment effectively attenuated colitis associated with decreased lamina propria CD4(+) lymphocytes and interferon-γ/IL-17 responses in colonic mucosa in IL-10(-/-) mice. After CD52 mAb treatment, attenuation of colonic permeability, increased epithelial expression and correct localization of tight junction proteins (occludin and zona occludens protein-1), as well as ameliorated tight junction morphology were observed in IL-10(-/-) mice. CD52 mAb treatment also effectively suppressed the epithelial apoptosis, mucosa TNF-α mRNA expression, epithelial expression of long MLCK, TNFR2 and phosphorylation of MLC. Our results indicated that anti-CD52 therapy may inhibit TNF-α/TNFR2-mediated epithelial apoptosis and MLCK-dependent tight junction permeability by depleting activated T cells in the gut mucosa. © 2014 John Wiley & Sons Ltd.

STAT3 Regulates Uterine Epithelial Remodeling and Epithelial-Stromal Crosstalk During Implantation

PubMed Central

Pawar, Sandeep; Starosvetsky, Elina; Orvis, Grant D.; Behringer, Richard R.; Bagchi, Indrani C.

2013-01-01

Embryo implantation is regulated by a variety of endometrial factors, including cytokines, growth factors, and transcription factors. Earlier studies identified the leukemia inhibitory factor (LIF), a cytokine produced by uterine glands, as an essential regulator of implantation. LIF, acting via its cell surface receptor, activates the signal transducer and activator of transcription 3 (STAT3) in the uterine epithelial cells. However, the precise mechanism via which activated STAT3 promotes uterine function during implantation remains unknown. To identify the molecular pathways regulated by STAT3, we created SWd/d mice in which Stat3 gene is conditionally inactivated in uterine epithelium. The SWd/d mice are infertile due to a lack of embryo attachment to the uterine luminal epithelium and consequent implantation failure. Gene expression profiling of uterine epithelial cells of SWd/d mice revealed dysregulated expression of specific components of junctional complexes, including E-cadherin, α- and β-catenin, and several claudins, which critically regulate epithelial junctional integrity and embryo attachment. In addition, uteri of SWd/d mice exhibited markedly reduced stromal proliferation and differentiation, indicating that epithelial STAT3 controls stromal function via a paracrine mechanism. The stromal defect arose from a drastic reduction in the production of several members of the epidermal growth factor family in luminal epithelium of SWd/d uteri and the resulting lack of activation of epidermal growth factor receptor signaling and mitotic activity in the stromal cells. Collectively, our results uncovered an intricate molecular network operating downstream of STAT3 that regulates uterine epithelial junctional reorganization, and stromal proliferation, and differentiation, which are critical determinants of successful implantation. PMID:24100212

Golgi sorting regulates organization and activity of GPI-proteins at apical membranes

PubMed Central

Tivodar, Simona; Formiggini, Fabio; Ossato, Giulia; Gratton, Enrico; Tramier, Marc; Coppey-Moisan, Maïté; Zurzolo, Chiara

2014-01-01

Here, we combined classical biochemistry with novel biophysical approaches to study with high spatial and temporal resolution the organization of GPI-anchored proteins (GPI-APs) at the plasma membrane of polarized epithelial cells. We show that in polarized MDCK cells, following sorting in the Golgi, each GPI-AP reaches the apical surface in homo-clusters. Golgi-derived homo-clusters are required for their subsequent plasma membrane organization into cholesterol-dependent hetero-clusters. By contrast, in non-polarized MDCK cells GPI-APs are delivered to the surface as monomers in an unpolarized manner and are not able to form hetero-clusters. We further demonstrate that this GPI-AP organization is regulated by the content of cholesterol in the Golgi apparatus and is required to maintain the functional state of the protein at the apical membrane. Thus, different from fibroblasts, in polarized epithelial cells a selective cholesterol-dependent sorting mechanism in the Golgi regulates both the organization and the function of GPI-APs at the apical surface. PMID:24681536

Salmonella Typhimurium Enzymatically Landscapes the Host Intestinal Epithelial Cell (IEC) Surface Glycome to Increase Invasion*

PubMed Central

Park, Dayoung; Arabyan, Narine; Williams, Cynthia C.; Song, Ting; Mitra, Anupam; Weimer, Bart C.; Lebrilla, Carlito B.

2016-01-01

Although gut host-pathogen interactions are glycan-mediated processes, few details are known about the participating structures. Here we employ high-resolution mass spectrometric profiling to comprehensively identify and quantitatively measure the exact modifications of native intestinal epithelial cell surface N-glycans induced by S. typhimurium infection. Sixty minutes postinfection, select sialylated structures showed decreases in terms of total number and abundances. To assess the effect of cell surface mannosylation, we selectively rerouted glycan expression on the host using the alpha-mannosidase inhibitor, kifunensine, toward overexpression of high mannose. Under these conditions, internalization of S. typhimurium significantly increased, demonstrating that bacteria show preference for particular structures. Finally, we developed a novel assay to measure membrane glycoprotein turnover rates, which revealed that glycan modifications occur by bacterial enzyme activity rather than by host-derived restructuring strategies. This study is the first to provide precise structural information on how host N-glycans are altered to support S. typhimurium invasion. PMID:27754876

Isotropic actomyosin dynamics promote organization of the apical cell cortex in epithelial cells.

PubMed

Klingner, Christoph; Cherian, Anoop V; Fels, Johannes; Diesinger, Philipp M; Aufschnaiter, Roland; Maghelli, Nicola; Keil, Thomas; Beck, Gisela; Tolić-Nørrelykke, Iva M; Bathe, Mark; Wedlich-Soldner, Roland

2014-10-13

Although cortical actin plays an important role in cellular mechanics and morphogenesis, there is surprisingly little information on cortex organization at the apical surface of cells. In this paper, we characterize organization and dynamics of microvilli (MV) and a previously unappreciated actomyosin network at the apical surface of Madin-Darby canine kidney cells. In contrast to short and static MV in confluent cells, the apical surfaces of nonconfluent epithelial cells (ECs) form highly dynamic protrusions, which are often oriented along the plane of the membrane. These dynamic MV exhibit complex and spatially correlated reorganization, which is dependent on myosin II activity. Surprisingly, myosin II is organized into an extensive network of filaments spanning the entire apical membrane in nonconfluent ECs. Dynamic MV, myosin filaments, and their associated actin filaments form an interconnected, prestressed network. Interestingly, this network regulates lateral mobility of apical membrane probes such as integrins or epidermal growth factor receptors, suggesting that coordinated actomyosin dynamics contributes to apical cell membrane organization. © 2014 Klingner et al.

Differential regulation of membrane-associated mucins in the human ocular surface epithelium.

PubMed

Hori, Yuichi; Spurr-Michaud, Sandra; Russo, Cindy Leigh; Argüeso, Pablo; Gipson, Ilene K

2004-01-01

Membrane-associated mucins present in the apical cells of the ocular surface epithelium (MUC1, -4, and -16) are believed to contribute to the maintenance of a hydrated and wet-surfaced epithelial phenotype. Serum and retinoic acid (RA) have been used to treat drying ocular surface diseases. The goal of this study was to determine whether serum or RA regulates the production of membrane-associated mucins in human conjunctival epithelial cells. A telomerase-immortalized human conjunctival epithelial cell line (HCjE) was used. Cells were cultured in serum-free medium to confluence and then cultured with either 10% calf serum or with 100 nM RA for 0 to 72 hours. Conventional RT-PCR was used to determine the expression of retinoic acid receptors (RARs) and quantitative real-time PCR was used to investigate the mRNA expression of MUC1, -4, and -16. Protein levels were assayed by immunoblot analysis, using the antibodies HMFG-2, 1G8, or OC125, which are specific to MUC1, -4 and -16, respectively. To determine whether RA-associated MUC4 mRNA induction is a direct or indirect effect, HCjE cells were treated with RA and the protein synthesis inhibitor cycloheximide (1.0 microg/mL) for 12 hours. MUC1 and -16, but not -4, mRNAs were detectable in HCjE cells grown in serum-free medium. Real-time PCR revealed that MUC4 mRNA was significantly induced by serum 3 hours after its addition, and that MUC1 and MUC16 mRNA levels were significantly upregulated at 72 hours. Western blot analysis demonstrated that the MUC1, -4, and -16 proteins increased over time after addition of serum. Conventional RT-PCR analysis demonstrated that RAR-alpha and -gamma mRNA were expressed in native human conjunctival tissue as well as in the HCjE cells. Treatment with RA upregulated the expression of both MUC4 and -16 mRNA and protein, but MUC1 was unaffected. Because the protein synthesis inhibitor cycloheximide did not prevent the RA-associated induction of MUC4 mRNA, the action of RA on the MUC4 promoter may be direct. The membrane-associated mucins of the ocular surface epithelia, MUC1, -4, and -16, are differentially regulated by serum and RA in the telomerase-immortalized human conjunctival epithelial cell line. Serum derived from vessels in the conjunctiva may play an important role in mucin regulation in the ocular surface epithelia. These data also support the clinical efficacy of autologous serum and RA application in patients with ocular surface diseases. Furthermore, the data suggest that MUC4 and -16 are particularly important hydrophilic molecules involved in maintenance of a healthy ocular surface.

Absence of surface-associated microorganisms in adult oysters (Crassostrea gigas).

PubMed Central

Garland, C D; Nash, G V; McMeekin, T A

1982-01-01

Healthy, actively feeding intertidal oysters were removed from an estuarine environment (Pipeclay Lagoon, Tasmania). The epithelial surfaces of various organs of the mantle cavity and alimentary tract were explored by scanning and transmission electron microscopy. All epithelial tissues examined were ciliated, and nearly all were partly covered with secreted mucus. However, microorganisms were seen rarely in the adhesive mucus and never attached to the epithelium. Electron microscopy also failed to demonstrate a surface microflora in emersed oysters which had been incubated at 5 to 25 degrees C for 6 or 24 h. The absence of an internal surface microflora did not vary on a seasonal basis. In laboratory experiments, oysters were allowed to filter feed from seawater containing diverse types of marine bacteria at concentrations of 10(3) to 10(7)/mL. However, no surface microflora could be found within actively feeding oysters or in emersed animals incubated at 20 degrees C for 6 or 24 h. In contrast, surface-associated microorganisms were detected readily by scanning electron microscopy on the external shell of healthy oysters and on various internal tissues in spoiled oysters. It is suggested that the major mechanisms restricting microbial growth within oysters are ciliary movement and mucus secretion. Images PMID:7181503

Magnetoelectric effects in single crystals of the cubic ferrimagnetic helimagnet Cu2OSeO3

NASA Astrophysics Data System (ADS)

Belesi, M.; Rousochatzakis, I.; Abid, M.; Rößler, U. K.; Berger, H.; Ansermet, J.-Ph.

2012-06-01

We present magnetodielectric measurements in single crystals of the cubic spin-1/2 compound Cu2OSeO3. A magnetic-field-induced electric polarization (P) and a finite magnetocapacitance (MC) is observed at the onset of the magnetically ordered state (Tc=59 K). Both P and MC are explored in considerable detail as a function of temperature (T), applied field Ha, and relative field orientations with respect to the crystallographic axes. The magnetodielectric data show a number of anomalies which signal magnetic phase transitions, and allow us to map out the phase diagram of the system in the Ha-T plane. Below the 3-up-1-down collinear ferrimagnetic phase, we find two additional magnetic phases. We demonstrate that these are related to the field-driven evolution of a long-period helical phase, which is stabilized by the chiral Dzyaloshinskii-Moriya term DM·(∇×M) that is present in this noncentrosymmetric compound. We also present a phenomenological Landau-Ginzburg theory for the magnetic-field-induced electric polarization (MEH) effect, which is in excellent agreement with experimental data, and shows three main features: (i) the polarization P has a uniform as well as a long-wavelength spatial component that is given by the pitch of the magnetic helices, (ii) the uniform component of P points along the vector (HyHz,HzHx,HxHy), and (iii) its strength is proportional to η∥2-η⊥2/2, where η∥ is the longitudinal and η⊥ is the transverse (and spiraling) component of the magnetic ordering. Hence, the field dependence of P provides a clear signature of the evolution of a conical helix under a magnetic field. A similar phenomenological theory is discussed for the MC.

Effects of endurance exercise training, metformin, and their combination on adipose tissue leptin and IL-10 secretion in OLETF rats

PubMed Central

Padilla, Jaume; Arce-Esquivel, Arturo A.; Bayless, David S.; Martin, Jeffrey S.; Leidy, Heather J.; Booth, Frank W.; Rector, R. Scott; Laughlin, M. Harold

2012-01-01

Adipose tissue inflammation plays a role in cardiovascular (CV) and metabolic diseases associated with obesity, insulin resistance, and type 2 diabetes mellitus (T2DM). The interactive effects of exercise training and metformin, two first-line T2DM treatments, on adipose tissue inflammation are not known. Using the hyperphagic, obese, insulin-resistant Otsuka Long-Evans Tokushima Fatty (OLETF) rat model, we tested the hypothesis that treadmill training, metformin, or a combination of these reduces the secretion of proinflammatory cytokines from adipose tissue. Compared with Long-Evans Tokushima Otsuka (LETO) control rats (L-Sed), sedentary OLETF (O-Sed) animals secreted significantly greater amounts of leptin from retroperitoneal adipose tissue. Conversely, secretion of interleukin (IL)-10 by O-Sed adipose tissue was lower than that in L-Sed animals. Examination of leptin and IL-10 secretion from adipose tissue in OLETF groups treated with endurance exercise training (O-EndEx), metformin treatment (O-Met), and a combination of these (O-E+M) from 20 to 32 wk of age indicated that 1) leptin secretion from adipose tissue was reduced in O-Met and O-E+M, but not O-EndEx animals; 2) adipose tissue IL-10 secretion was increased in O-EndEx and O-E+M but not in O-Met animals; and 3) only the combined treatment (O-E+M) displayed both a reduction in leptin secretion and an increase in IL-10 secretion. Leptin and IL-10 concentrations in adipose tissue–conditioned buffers were correlated with their plasma concentrations, adipocyte diameters, and total adiposity. Overall, this study indicates that exercise training and metformin have additive influences on adipose tissue secretion and plasma concentrations of leptin and IL-10. PMID:23019312

Potential for Aedes albopictus and Ochlerotatus j. japonicus to Change the Field Ecology of Arboviruses of Human Health Importance in the Mid-Atlantic Region of the United States

DTIC Science & Technology

2001-10-16

in the midgut epithelial cells. Step 3 is release 17 of virus from the midgut epithelial cell into the hemolymph. Step 4 is infection of the...proteins, maturation, and budding. During attachment, the viral attachment proteins on the surface of the virion bind to receptors on the microvillar...membrane of the mosquito s midgut . Penetration refers to the process through which the virions enter the midgut cells; arboviruses enter cell

Management strategies for persistent epithelial defects of the cornea

PubMed Central

Katzman, Lee R.; Jeng, Bennie H.

2014-01-01

Management of patients with persistent epithelial defects of the cornea can be challenging to even the seasoned ophthalmologist. It is essential that one understands not only the pathophysiology of the failure of the epithelium to migrate and close a wound appropriately, but also the mechanism of action of the available treatment modalities at one’s disposal. This article serves as a review of current standard therapies, recently introduced alternative therapies gaining in popularity, and a look into the newest developments that may change the way we manage corneal surface disease. PMID:25278792

[BIOCOMPATIBILITY OF POLY-LACTIDE-CO-GLYCOLIDE/COLLAGEN TYPE I SCAFFOLD WITH RAT VAGINAL EPITHELIAL CELLS].

PubMed

Li, Yachai; Huang, Xianghua; Zhang, Mingle; Li, Yanan; Chen, Yexing; Jia, Jingfei

2015-09-01

To explore the biocompatibility of the poly-lactide-co-glycolide (PLGA)/collagen type I scaffold with rat vaginal epithelial cells, and the feasibility of using PLGA/collagen type I as scaffold to reconstruct vagina by the tissue engineering. PLGA/collagen type I scaffold was prepared with PLGA covered polylysine and collagen type I. The vaginal epithelial cells of Sprague Dawley rat of 10-12 weeks old were cultured by enzyme digestion method. The vaginal epithelial cells of passage 2 were cultured in the leaching liquor of scaffold for 48 hours to detect its cytotoxicity by MTT. The vaginal epithelial cells were inoculated on the PLGA/collagen type I scaffold (experimental group) and PLGA scaffold (control group) to calculate the cell adhesion rate. Epithelial cells-scaffold complexes were implanted subcutaneously on the rat back. At 2, 4, and 8 weeks after implantation, the epithelial cells-scaffold complexes were harvested to observe the cell growth by HE staining and immunohistochemical analysis. The epithelial cells-scaffold complexes were transplanted to reconstruct vagina in 6 rats with vaginal defect. After 3 and 6 months, the vaginal length was measured and the appearance was observed. The neovagina tissues were harvested for histological evaluation after 6 months. The epithelial cells grew and proliferated well in the leaching liquor of PLGA/collagen type I scaffold, and the cytotoxicity was at grade 1. The cell adhesion rate on the PLGA/collagen type I scaffold was 71.8%±9.2%, which significantly higher than that on the PLGA scaffold (63.4%±5.7%) (t=2.195, P=0.005). The epithelial cells could grow and adhere to the PLGA/collagen type I scaffolds. At 2 weeks after implanted subcutaneously, the epithelial cells grew and proliferated in the pores of scaffolds, and the fibroblasts were observed. At 4 weeks, 1-3 layers epithelium formed on the surface of scaffold. At 8 weeks, the epithelial cells increased and arranged regularly, which formed the membrane-like layer on the scaffold. The keratin expression of the epithelium was positive. At 3 months after transplantation in situ, the vaginal mucosa showed pink and lustrous epithelialization, and the majority of scaffold degraded. After 6 months, the neovagina length was 1.2 cm, without obvious stenosis; the vaginal mucosa had similar appearance and epithelial layer to normal vagina, but it had less duplicature; there were nail-like processes in the basal layer, but the number was less than that of normal vagina. The immunohistochemistry staining for keratin was positive. The PLGA/collagen type I scaffolds have good cytocompatibility with the epithelial cells, and can be used as the biodegradable polymer scaffold of the vaginal tissue engineering.

Targeting autophagy as a novel strategy for facilitating the therapeutic action of potentiators on ΔF508 cystic fibrosis transmembrane conductance regulator

PubMed Central

Luciani, Alessandro; Villella, Valeria Rachela; Esposito, Speranza; Gavina, Manuela; Russo, Ilaria; Silano, Marco; Guido, Stefano; Pettoello-Mantovani, Massimo; Carnuccio, Rosa; Scholte, Bob; De Matteis, Antonella; Maiuri, Maria Chiara; Raia, Valeria; Luini, Alberto; Kroemer, Guido; Maiuri, Luigi

2012-01-01

Channel activators (potentiators) of cystic fibrosis (CF) transmembrane conductance regulator (CFTR), can be used for the treatment of the small subset of CF patients that carry plasma membrane-resident CFTR mutants. However, approximately 90% of CF patients carry the misfolded ΔF508-CFTR and are poorly responsive to potentiators, because ΔF508-CFTR is intrinsically unstable at the plasma membrane (PM) even if rescued by pharmacological correctors. We have demonstrated that human and mouse CF airways are autophagy deficient due to functional sequestration of BECN1 and that the tissue transglutaminase-2 inhibitor, cystamine, or antioxidants restore BECN1-dependent autophagy and reduce SQSTM1/p62 levels, thus favoring ΔF508-CFTR trafficking to the epithelial surface. Here, we investigated whether these treatments could facilitate the beneficial action of potentiators on ΔF508-CFTR homozygous airways. Cystamine or the superoxide dismutase (SOD)/catalase-mimetic EUK-134 stabilized ΔF508-CFTR at the plasma membrane of airway epithelial cells and sustained the expression of CFTR at the epithelial surface well beyond drug withdrawal, overexpressing BECN1 and depleting SQSTM1. This facilitates the beneficial action of potentiators in controlling inflammation in ex vivo ΔF508-CFTR homozygous human nasal biopsies and in vivo in mouse ΔF508-CFTR lungs. Direct depletion of Sqstm1 by shRNAs in vivo in ΔF508-CFTR mice synergized with potentiators in sustaining surface CFTR expression and suppressing inflammation. Cystamine pre-treatment restored ΔF508-CFTR response to the CFTR potentiators genistein, Vrx-532 or Vrx-770 in freshly isolated brushed nasal epithelial cells from ΔF508-CFTR homozygous patients. These findings delineate a novel therapeutic strategy for the treatment of CF patients with the ΔF508-CFTR mutation in which patients are first treated with cystamine and subsequently pulsed with CFTR potentiators. PMID:22874563

Targeting autophagy as a novel strategy for facilitating the therapeutic action of potentiators on ΔF508 cystic fibrosis transmembrane conductance regulator.

PubMed

Luciani, Alessandro; Villella, Valeria Rachela; Esposito, Speranza; Gavina, Manuela; Russo, Ilaria; Silano, Marco; Guido, Stefano; Pettoello-Mantovani, Massimo; Carnuccio, Rosa; Scholte, Bob; De Matteis, Antonella; Maiuri, Maria Chiara; Raia, Valeria; Luini, Alberto; Kroemer, Guido; Maiuri, Luigi

2012-11-01

Channel activators (potentiators) of cystic fibrosis (CF) transmembrane conductance regulator (CFTR), can be used for the treatment of the small subset of CF patients that carry plasma membrane-resident CFTR mutants. However, approximately 90% of CF patients carry the misfolded ΔF508-CFTR and are poorly responsive to potentiators, because ΔF508-CFTR is intrinsically unstable at the plasma membrane (PM) even if rescued by pharmacological correctors. We have demonstrated that human and mouse CF airways are autophagy deficient due to functional sequestration of BECN1 and that the tissue transglutaminase-2 inhibitor, cystamine, or antioxidants restore BECN1-dependent autophagy and reduce SQSTM1/p62 levels, thus favoring ΔF508-CFTR trafficking to the epithelial surface. Here, we investigated whether these treatments could facilitate the beneficial action of potentiators on ΔF508-CFTR homozygous airways. Cystamine or the superoxide dismutase (SOD)/catalase-mimetic EUK-134 stabilized ΔF508-CFTR at the plasma membrane of airway epithelial cells and sustained the expression of CFTR at the epithelial surface well beyond drug withdrawal, overexpressing BECN1 and depleting SQSTM1. This facilitates the beneficial action of potentiators in controlling inflammation in ex vivo ΔF508-CFTR homozygous human nasal biopsies and in vivo in mouse ΔF508-CFTR lungs. Direct depletion of Sqstm1 by shRNAs in vivo in ΔF508-CFTR mice synergized with potentiators in sustaining surface CFTR expression and suppressing inflammation. Cystamine pre-treatment restored ΔF508-CFTR response to the CFTR potentiators genistein, Vrx-532 or Vrx-770 in freshly isolated brushed nasal epithelial cells from ΔF508-CFTR homozygous patients. These findings delineate a novel therapeutic strategy for the treatment of CF patients with the ΔF508-CFTR mutation in which patients are first treated with cystamine and subsequently pulsed with CFTR potentiators.

Rationale for Developing a Specimen Bank to Study the Pathogenesis of High-Grade Serous Carcinoma: A Review of the Evidence.

PubMed

Sherman, Mark E; Drapkin, Ronny I; Horowitz, Neil S; Crum, Christopher P; Friedman, Sue; Kwon, Janice S; Levine, Douglas A; Shih, Ie-Ming; Shoupe, Donna; Swisher, Elizabeth M; Walker, Joan; Trabert, Britton; Greene, Mark H; Samimi, Goli; Temkin, Sarah M; Minasian, Lori M

2016-09-01

Women with clinically detected high-grade serous carcinomas (HGSC) generally present with advanced-stage disease, which portends a poor prognosis, despite extensive surgery and intensive chemotherapy. Historically, HGSCs were presumed to arise from the ovarian surface epithelium (OSE), but the inability to identify early-stage HGSCs and their putative precursors in the ovary dimmed prospects for advancing our knowledge of the pathogenesis of these tumors and translating these findings into effective prevention strategies. Over the last decade, increased BRCA1/2 mutation testing coupled with performance of risk-reducing surgeries has enabled studies that have provided strong evidence that many, but probably not all, HGSCs among BRCA1/2 mutation carriers appear to arise from the fallopian tubes, rather than from the ovaries. This shift in our understanding of the pathogenesis of HGSCs provides an important opportunity to achieve practice changing advances; however, the scarcity of clinically annotated tissues containing early lesions, particularly among women at average risk, poses challenges to progress. Accordingly, we review studies that have kindled our evolving understanding of the pathogenesis of HGSC and present the rationale for developing an epidemiologically annotated national specimen resource to support this research. Cancer Prev Res; 9(9); 713-20. ©2016 AACR. ©2016 American Association for Cancer Research.

Optimization of selenizing conditions for Seleno-Lentinan and its characteristics.

PubMed

Ren, Guangming; Li, Koukou; Hu, Yang; Yu, Min; Qu, Juanjuan; Xu, Xiuhong

2015-11-01

Lentinan was successfully modified with nitric acid-sodium selenite method based on L9(3(4)) orthogonal experiments. The optimum selenizing conditions were obtained according to selenium conversion rate as follows: Lentinan of 1.0g, pH of 4.5, temperature of 70°C and sodium selenite of 1.50g. The antioxidant activity assays in vitro (DPPH, reducing power, superoxide radicals and hydroxyl radicals) proved that Lentinan had stronger antioxidant activity after selenizing. The elevations of serum alanine aminotransferase and aspartate aminotransferase, as well as the abnormal hepatic architecture, verified that oral administration of Seleno-Lentinan (SL2-1) markedly alleviated oxidative damage in the liver of mice induced by D-gal. In addition, SL2-1 significantly increased total antioxidant capacity, activities and protein expressions of catalase and glutathione peroxidase and lowered malondialdehyde levels in serum and liver. Fourier transform infrared spectroscopy analysis indicated that selenium of SL2-1 was mostly existed as the formations of OSeO, SeO and SeOC. Scanning electron microscope coupled with energy dispersive X-ray spectroscopy analysis revealed that the surface structure and elemental components of Lentinan significantly changed after selenizing. The results are instructive for the development of organic selenium-supplement resource. Copyright © 2015 Elsevier B.V. All rights reserved.

Functional lacrimal gland regeneration by transplantation of a bioengineered organ germ

PubMed Central

Hirayama, Masatoshi; Ogawa, Miho; Oshima, Masamitsu; Sekine, Yurie; Ishida, Kentaro; Yamashita, Kentaro; Ikeda, Kazutaka; Shimmura, Shigeto; Kawakita, Tetsuya; Tsubota, Kazuo; Tsuji, Takashi

2013-01-01

The lacrimal gland has a multifaceted role in maintaining a homeostatic microenvironment for a healthy ocular surface via tear secretion. Dry-eye disease, which is caused by lacrimal gland dysfunction, is one of the most prevalent eye diseases that cause corneal epithelial damage and results in significant loss of vision and a reduction in the quality of life. Here we demonstrate orthotopic transplantation of bioengineered lacrimal gland germs into adult mice with an extra-orbital lacrimal gland defect, a mouse model that mimics the corneal epithelial damage caused by lacrimal gland dysfunction. The bioengineered lacrimal gland germs and harderian gland germs both develop in vivo and achieve sufficient physiological functionality, including tear production in response to nervous stimulation and ocular surface protection. This study demonstrates the potential for bioengineered organ replacement to functionally restore the lacrimal gland. PMID:24084941

Effect of Stratification on Surface Properties of Corneal Epithelial Cells

PubMed Central

Yáñez-Soto, Bernardo; Leonard, Brian C.; Raghunathan, Vijay Krishna; Abbott, Nicholas L.; Murphy, Christopher J.

2015-01-01

Purpose The purpose of this study was to determine the influence of mucin expression in an immortalized human corneal epithelial cell line (hTCEpi) on the surface properties of cells, such as wettability, contact angle, and surface heterogeneity. Methods hTCEpi cells were cultured to confluence in serum-free medium. The medium was then replaced by stratification medium to induce mucin biosynthesis. The mucin expression profile was analyzed using quantitative PCR and Western blotting. Contact angles were measured using a two-immiscible liquid method, and contact angle hysteresis was evaluated by tilting the apparatus and recording advancing and receding contact angles. The spatial distribution of mucins was evaluated with fluorescently labeled lectin. Results hTCEpi cells expressed the three main ocular mucins (MUC1, MUC4, and MUC16) with a maximum between days 1 and 3 of the stratification process. Upon stratification, cells caused a very significant increase in contact angle hysteresis, suggesting the development of spatially discrete and heterogeneously distributed surface features, defined by topography and/or chemical functionality. Although atomic force microscopy measurements showed no formation of appreciable topographic features on the surface of the cells, we observed a significant increase in surface chemical heterogeneity. Conclusions The surface chemical heterogeneity of the corneal epithelium may influence the dynamic behavior of tear film by “pinning” the contact line between the cellular surface and aqueous tear film. Engineering the surface properties of corneal epithelium could potentially lead to novel treatments in dry eye disease. PMID:26747762

Characteristic Changes in Cell Surface Glycosylation Accompany Intestinal Epithelial Cell (IEC) Differentiation: High Mannose Structures Dominate the Cell Surface Glycome of Undifferentiated Enterocytes*

PubMed Central

Park, Dayoung; Brune, Kristin A.; Mitra, Anupam; Marusina, Alina I.; Maverakis, Emanual; Lebrilla, Carlito B.

2015-01-01

Changes in cell surface glycosylation occur during the development and differentiation of cells and have been widely correlated with the progression of several diseases. Because of their structural diversity and sensitivity to intra- and extracellular conditions, glycans are an indispensable tool for analyzing cellular transformations. Glycans present on the surface of intestinal epithelial cells (IEC) mediate interactions with billions of native microorganisms, which continuously populate the mammalian gut. A distinct feature of IECs is that they differentiate as they migrate upwards from the crypt base to the villus tip. In this study, nano-LC/ESI QTOF MS profiling was used to characterize the changes in glycosylation that correspond to Caco-2 cell differentiation. As Caco-2 cells differentiate to form a brush border membrane, a decrease in high mannose type glycans and a concurrent increase in fucosylated and sialylated complex/hybrid type glycans were observed. At day 21, when cells appear to be completely differentiated, remodeling of the cell surface glycome ceases. Differential expression of glycans during IEC maturation appears to play a key functional role in regulating the membrane-associated hydrolases and contributes to the mucosal surface innate defense mechanisms. Developing methodologies to rapidly identify changes in IEC surface glycans may lead to a rapid screening approach for a variety of disease states affecting the GI tract. PMID:26355101

Activation of Rho GTPases by Cytotoxic Necrotizing Factor 1 Induces Macropinocytosis and Scavenging Activity in Epithelial Cells

PubMed Central

Fiorentini, Carla; Falzano, Loredana; Fabbri, Alessia; Stringaro, Annarita; Logozzi, Mariaantonia; Travaglione, Sara; Contamin, Stéphanette; Arancia, Giuseppe; Malorni, Walter; Fais, Stefano

2001-01-01

Macropinocytosis, a ruffling-driven process that allows the capture of large material, is an essential aspect of normal cell function. It can be either constitutive, as in professional phagocytes where it ends with the digestion of captured material, or induced, as in epithelial cells stimulated by growth factors. In this case, the internalized material recycles back to the cell surface. We herein show that activation of Rho GTPases by a bacterial protein toxin, the Escherichia coli cytotoxic necrotizing factor 1 (CNF1), allowed epithelial cells to engulf and digest apoptotic cells in a manner similar to that of professional phagocytes. In particular, we have demonstrated that 1) the activation of all Rho, Rac, and Cdc42 by CNF1 was essential for the capture and internalization of apoptotic cells; and 2) such activation allowed the discharge of macropinosomal content into Rab7 and lysosomal associated membrane protein-1 acidic lysosomal vesicles where the ingested particles underwent degradation. Taken together, these findings indicate that CNF1-induced “switching on” of Rho GTPases may induce in epithelial cells a scavenging activity, comparable to that exerted by professional phagocytes. The activation of such activity in epithelial cells may be relevant, in mucosal tissues, in supporting or integrating the scavenging activity of resident macrophages. PMID:11452003

Controlled-release of epidermal growth factor from cationized gelatin hydrogel enhances corneal epithelial wound healing.

PubMed

Hori, Kuniko; Sotozono, Chie; Hamuro, Junji; Yamasaki, Kenta; Kimura, Yu; Ozeki, Makoto; Tabata, Yasuhiko; Kinoshita, Shigeru

2007-04-02

We designed a new ophthalmic drug-delivery system for epidermal growth factor (EGF) from the biodegradable hydrogel of cationized gelatin. We placed a cationized gelatin hydrogel (CGH) with incorporated (125)I-labelled EGF in the conjunctival sac of mice and measured the residual radioactivity at different times to evaluate the in vivo profile of EGF release. Approximately 60-67% and 10-12% of EGF applied initially remained 1 and 7 days after application, respectively; whereas EGF delivered in topically applied solution or via EGF impregnation of soft contact lenses disappeared within the first day. We also placed CGH films with 5.0 mug of incorporated EGF on round corneal defects in rabbits to evaluate the healing process using image analysis software and to assess epithelial proliferation immunohistochemically by counting the number of Ki67-positive cells. The application of a CGH film with incorporated EGF resulted in a reduction in the epithelial defect in rabbit corneas accompanied by significantly enhanced epithelial proliferation compared with the reduction seen after the topical application of EGF solution or the placement of an EGF-free CGH film. The controlled release of EGF from a CGH placed over a corneal epithelial defect accelerated ocular surface wound healing.

Delayed Epithelial Closure After PRK Associated With Topical Besifloxacin Use.

PubMed

Talamo, Jonathan H; Hatch, Kathryn M; Woodcock, Emily C

2013-10-01

To report the observation of prolonged reepithelialization after photorefractive keratectomy (PRK) associated with the use of besifloxacin 0.6% (Besivance; Bausch & Lomb, Rochester, NY) underneath bandage contact lenses (BCLs) placed during surgery. An office-based private practice and retrospective chart review. The healing parameters examined included epithelial healing time, haze formation, discomfort, and visual recovery of 4 patients (7 eyes) treated with besifloxacin 0.6% under BCLs placed after the PRK was performed. All the eyes had delayed epithelial closure (mean, 8.8 days; range 5-13 days). All the patients experienced a delayed visual recovery and significant pain after the surgery, and 2 of 4 patients experienced recurrent corneal erosions for weeks to months after they underwent the PRK. All but 1 eye developed corneal haze persisting for 1 year or more after the surgery. Only 1 eye among the 7 eyes treated with besifloxacin 0.6% under the BCL had 20/20 or better uncorrected visual acuity 3 months postoperatively. All the patients treated with besifloxacin 0.6% on the stromal bed exhibited significant problems with corneal epithelial healing and delayed visual recovery. We caution the use of besifloxacin 0.6% underneath a BCL during a PRK or other ocular surface surgeries requiring corneal epithelial debridement.