Дисертації з теми "Epithelial permeability"
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Dennison, Patrick Winford. "Epithelial permeability in asthma." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/416625/.
Повний текст джерелаAnderson, Keith G. "Modulation and quantitation of epithelial paracellular permeability." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324937.
Повний текст джерелаCollares, Buzato Carla Beatriz. "Modulation of paracellular permeability and intercellular junctions in cultured epithelia." Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283019.
Повний текст джерелаShang, Valerie C. M. "The effects of endocannabinoids and phytocannabinoids on bronchial epithelial permeability." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/31264/.
Повний текст джерелаWillemsen, Linette Eustachia Maria. "Intestinal barrier function: regulation of epithelial permeability and mucin expression." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2004. http://dare.uva.nl/document/74526.
Повний текст джерелаRubelt, Miriam. "Enhancement of the intestinal epithelial permeability of peripherally acting opioid analgesics by chitosan." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2013. http://dx.doi.org/10.18452/16864.
Повний текст джерелаAnalgesic effects of opioids are mediated by opioid receptors that are widely distributed in the central and peripheral nervous systems (CNS and PNS, respectively). Although opioids are the most powerful analgesics, severe side effects restrict their use and affect patient convalescence. This suggests an advantage of new analgesic opioids which selectively bind to opioid receptors in the PNS. After oral administration however, peripherally restricted opioids first have to cross the intestinal epithelial barrier before absorption into the circulation and distribution to opioid receptors in peripheral tissues. Here, the transport across intestinal epithelia of two opioid ligands (AS006 and loperamide) that selectively activate peripheral opioid receptors without entering the CNS were investigated. To increase the intestinal passage of these drugs, the absorption enhancer chitosan was used. Chitosan significantly decreased the transepithelial resistance of HT29/B6 and Caco-2 cell monolayers after 30 min in vitro. The permeability values for AS006 increased from < 0.3 × 10-6 cm/s up to 10 × 10-6 cm/s in the presence of chitosan. In contrast, HT29/B6 monolayers showed moderate loperamide permeability in the presence of chitosan, and chitosan had no effect on the permeability of loperamide using Caco-2 monolayers. Oral administration of loperamide induced a dose-depended elevation of paw pressure thresholds in inflamed paws that lasted for 60 min. Oral administration of loperamide combined with chitosan slightly but nonsignificantly enhanced the antinociceptive effect of loperamide. In conclusion, chitosan is a suitable absorption enhancer for in vitro intestinal permeability studies. Future in vivo experiments might investigate different formulations and application schedules, and further address the effects of chitosan on the antinociceptive efficacy of hydrophilic opioids.
Yi, Sheng. "Synthetic peptides modulate epithelial junctions." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2344.
Повний текст джерелаElghadban, Salma. "Role of matriptase in the regulation of epithelial barrier permeability studied using MDCK cells." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/53377/.
Повний текст джерелаLe, Nga Thi Thanh. "Regulation of Intestinal Epithelial Barrier and Immune Function by Activated T Cells." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1599833768774075.
Повний текст джерелаViljoen, Ianda. "The role of surfactant in, and a comparison of, the permeability of porcine and human epithelia to various chemical compounds." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1287.
Повний текст джерелаMcGilligan, Victoria. "The protective mechanisms of nicotine in relation to intestinal epithelial permeability and inflammation in ulcerative colitis." Thesis, University of Ulster, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445045.
Повний текст джерелаCruchley, Alan Timothy. "The relationship between epithelial permeability and the Langerhans cell population of normal human oral mucosa and skin." Thesis, Queen Mary, University of London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281739.
Повний текст джерелаLagerquist, Hägglund Christine. "Affinity-, partition- and permeability properties of the human red blood cell membrane and biomembrane models, with emphasis on the GLUT1 glucose transporter /." Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3525.
Повний текст джерелаSonawane, Amit. "Evaluation of novel efflux transport inhibitor for the improvement of drug delivery through epithelial cell monolayer." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/14424.
Повний текст джерелаRubelt, Miriam [Verfasser], Hans-Dieter [Akademischer Betreuer] Volk, Salah [Akademischer Betreuer] Amasheh, and Matthew [Akademischer Betreuer] Larkum. "Enhancement of the intestinal epithelial permeability of peripherally acting opioid analgesics by chitosan / Miriam Rubelt. Gutachter: Hans-Dieter Volk ; Salah Amasheh ; Matthew Larkum." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2013. http://d-nb.info/1045951439/34.
Повний текст джерелаChung, Charlotte Yuk-Yan. "Tight Junctions - The Link Between HIV-Associated Intestinal Barrier Dysfunction and Loss of Immune Homeostasis." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1417822947.
Повний текст джерелаNag, Subhra Sankar. "Stabilization of Hypoxia Inducible Factor by Cobalt Chloride Can Alter Renal Transepithelial Transport." Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1536931227678351.
Повний текст джерелаTretiach, Marina Louise. "Bovine Models of Human Retinal Disease: Effect of Perivascular Cells on Retinal Endothelial Cell Permeability." University of Sydney, 2005. http://hdl.handle.net/2123/1153.
Повний текст джерелаBackground: Diabetic vascular complications affect both the macro- and microvasculature. Microvascular pathology in diabetes may be mediated by biochemical factors that precipitate cellular changes at both the gene and protein levels. In the diabetic retina, vascular pathology is found mainly in microvessels, including the retinal precapillary arterioles, capillaries and venules. Macular oedema secondary to breakdown of the inner blood-retinal barrier is the most common cause of vision impairment in diabetic retinopathy. Müller cells play a critical role in the trophic support of retinal neurons and blood vessels. In chronic diabetes, Müller cells are increasingly unable to maintain their supportive functions and may themselves undergo changes that exacerbate the retinal pathology. The consequences of early diabetic changes in retinal cells are primarily considered in this thesis. Aims: This thesis aims to investigate the effect of perivascular cells (Müller cells, RPE, pericytes) on retinal endothelial cell permeability using an established in vitro model. Methods: Immunohistochemistry, cell morphology and cell growth patterns were used to characterise primary bovine retinal cells (Müller cells, RPE, pericytes and endothelial cells). An in vitro model of the blood-retinal barrier was refined by coculturing retinal endothelial cells with perivascular cells (Müller cells or pericytes) on opposite sides of a permeable Transwell filter. The integrity of the barrier formed by endothelial cells was assessed by transendothelial electrical resistance (TEER) measurements. Functional characteristics of endothelial cells were compared with ultrastructural morphology to determine if different cell types have barrier-enhancing effects on endothelial cell cultures. Once the co-culture model was established, retinal endothelial cells and Müller cells were exposed to different environmental conditions (20% oxygen, normoxia; 1% oxygen, hypoxia) to examine the effect of perivascular cells on endothelial cell permeability under reduced oxygen conditions. Barrier integrity was assessed by TEER measurements and permeability was measured by passive diffusion of radiolabelled tracers from the luminal to the abluminal side of the endothelial cell barrier. A further study investigated the mechanism of laser therapy on re-establishment of retinal endothelial cell barrier integrity. Müller cells and RPE, that comprise the scar formed after laser photocoagulation, and control cells (Müller cells and pericytes, RPE cells and ECV304, an epithelial cell line) were grown in long-term culture and treated with blue-green argon laser. Lasered cells were placed underneath confluent retinal endothelial cells growing on a permeable filter, providing conditioned medium to the basal surface of endothelial cells. The effect of conditioned medium on endothelial cell permeability was determined, as above. Results: Co-cultures of retinal endothelial cells and Müller cells on opposite sides of a permeable filter showed that Müller cells can enhance the integrity of the endothelial cell barrier, most likely through soluble factors. Low basal resistances generated by endothelial cells from different retinal isolations may be the result of erratic growth characteristics (determined by ultrastructural studies) or the selection of vessel fragments without true âbarrier characteristicsâ in the isolation step. When Müller cells were co-cultured in close apposition to endothelial cells under normoxic conditions, the barrier integrity was enhanced and permeability was reduced. Under hypoxic conditions, Müller cells had a detrimental effect on the integrity of the endothelial cell barrier and permeability was increased in closely apposed cells. Conditioned medium from long-term cultured Müller cells and RPE that typically comprise the scar formed after lasering, enhanced TEER and reduced permeability of cultured endothelial cells. Conclusions: These studies confirm that bovine tissues can be used as a suitable model to investigate the role of perivascular cells on the permeability of retinal endothelial cells. The dual effect of Müller cells on the retinal endothelial cell barrier under different environmental conditions, underscores the critical role of Müller cells in regulating the blood-retinal barrier in health and disease. These studies also raise the possibility that soluble factor(s) secreted by Müller cells and RPE subsequent to laser treatment reduce the permeability of retinal vascular endothelium. Future studies to identify these factor(s) may have implications for the clinical treatment of macular oedema secondary to diseases including diabetic retinopathy.
Dasdelen, Süha [Verfasser], and Stephan [Akademischer Betreuer] Böhm. "Einfluss des PAR-2 auf die epitheliale Permeabilität und Ionensekretion im Gastrointestinaltrakt / Süha Dasdelen. Betreuer: Stephan Böhm." Marburg : Philipps-Universität Marburg, 2012. http://d-nb.info/1029819351/34.
Повний текст джерелаSalmon, Damien. "Usage biopharmaceutique in vitro combiné des hydrogels thermoréversibles et d’une cellule de diffusion innovante." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1056/document.
Повний текст джерелаBiopharmacy studies the outcomes of contact between a medicine and its administration site epithelium, thus determining active compound bioavailability. Hence, biopharmaceutical studies are paramount to drug development processes. Biopharmaceutical data are obtained in vitro using experimental devices (i.e., diffusion cells) but show high variability. To overcome this limitation we development a new experimental device, called VitroPharma, meant to optimize the study of epithelial permeability. Distinctiveness of this innovating diffusion cell is due to substitution of classical liquid receptor medium with semi-solid medium.In this work, validation studies of VitroPharma are detailed including (i) finite and (ii) infinite dosing protocols using (i) biological membrane (i.e., pig ear skin) and (ii) artificial silicone membrane, respectively. Three different types of receptor medium are employed: (i) liquid medium, (ii) semi-solid medium (i.e., 2% agarose hydrogel) and (iii) thermogelifying medium (i.e., 20% poloxamer 407 hydrogel). Caffeine and testosterone are used as model compounds. Permeability results are displayed and compared to that obtained using reference Franz static diffusion cell.Furthermore, two experimental pitfalls often mentioned but scarcely studied in literature are evaluated, that is (i) bubble formation at the membrane-receptor medium interface and (ii) biological membrane hydration modification over assay time. VitroPharma combined to thermogelifying receptor medium was found efficient (i) in reducing bubble formation and (ii) enabling control of biological membrane water content.Therefore, VitroPharma appears adapted to the in vitro study of epithelial permeability, enabling (i) easy handling, (ii) optimized experimental parameters and (iii) dual penetration and permeation determination. To conclude this work, examples of clinical outcomes that could advantageously use VitroPharma are presented
Carlowitz, Corinna von [Verfasser]. "Die Wirkung von Adrenomedullin auf die epitheliale Permeabilität des Darms in vivo und in vitro / Corinna von Carlowitz." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2018. http://d-nb.info/1153769298/34.
Повний текст джерелаJuel, Ingebjørg S. "Intestinal injury and recovery after ishemia - An experimental study on restitution of the surface epithelium, intestinal permeability, and release of biomarkers from the mucosa." Doctoral thesis, Norwegian University of Science and Technology, Department of Cancer Research and Molecular Medicine, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1817.
Повний текст джерелаJaussaud, Alain. "Etude de la perméabilité épithéliale cornéenne par fluorophotométrie, chez des patients glaucomateux, avant et après traitement par timolol." Montpellier 1, 1996. http://www.theses.fr/1996MON11039.
Повний текст джерелаMonteiro, Talita Ferreira. "Desenvolvimento de novo método ex vivo para estudo da permeabilidade de fármacos utilizando epitélio intestinal de rã-touro (Rana catesbeiana)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/9/9139/tde-28032013-121959/.
Повний текст джерелаThis work aimed to propose a new method for studying drug permeability using frog intestinal epithelium (Rana catesbeiana) in ex vivo method, using Franz cells. By using intestinal epithelium, a disposal material from an animal used as human food, can be considered an alternative method, because it doesn\'t involve the sacrifice of animals. The amount of permeated drug was determined by capillary electrophoresis method with UV detection and validated for antiviral drugs lamivudine, zidovudine and acyclovir in the presence of metoprolol and floridizina. The drug chosen as a model in permeability studies was lamivudine. To establish the experimental protocol for the permeability studies, a three-way analysis of variance was proposed to check the influence of intestinal section, pH of Ringer\'s solution and the temperature on the permeability. Total amount of drug permeated (Qt), apparent permeability coefficient (Papp) and first-order constant absorption (ka) were determined. By the analysis of experimental design, the effects of the variables were not significant, except for intestinal section. The results of apparent permeability coefficient (Papp) obtained were 0.09 x 10-4 cm/s for lamivudine and 0.22 x 10-4 cm/s for metoprolol. The value of Papp obtained for metoprolol is quite close to the values found in literature for other methods. For lamivudine, however, the difference found in comparison to Caco-2 cells may be due to different techniques.
Salim, Sa'ad Yislam. "Mucosal dendritic cells in inflammatory bowel disease." Doctoral thesis, Linköpings universitet, Kirurgi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-52234.
Повний текст джерелаKeita, Åsa. "Barrier function of the Follicle-Associated Epithelium in Stress and Crohn's disease." Doctoral thesis, Linköpings universitet, Kirurgi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9271.
Повний текст джерелаThe earliest observable signs of Crohn’s disease are microscopic erosions in the follicle-associated epithelium (FAE) covering the Peyer’s patches. The FAE, which contains M cells, is specialised in sampling of luminal content and delivery to underlying immune cells. This sampling is crucial for induction of protective immune responses, but it also provides a route of entry for microorganisms into the mucosa. Crohn’s disease is associated with an increased immune response to bacteria, and the disease course can be altered by stress. The overall aim of this thesis was to study the effects of stress on the FAE and elucidate the role of FAE in the development of intestinal inflammation, specifically Crohn’s disease. Initially, rats were submitted to acute and chronic water avoidance stress to study the effects of psychological stress on the FAE. Stressed rats showed enhanced antigen and bacterial passage, and the passage was higher in FAE than in regular villus epithelium (VE). Further, stress gave rise to ultrastructural changes. Subsequent experiments revealed the stress-induced increase in permeability to be regulated by corticotropin-releasing hormone and mast cells. Furthermore, vasoactive intestinal peptide (VIP) mimicked the stress effects on permeability, and the VIP effects were inhibited by a mast cell stabiliser. Human studies of ileal mucosa from patients with non-inflammatory disease and healthy controls showed a higher antigen and bacterial passage in FAE than in VE. In patients with Crohn’s disease, the bacterial passage across the FAE was significantly increased compared to non-inflammatory and inflammatory controls (ulcerative colitis). Furthermore, there was an enhanced uptake of bacteria into dendritic cells, and augmented TNF-α release in Crohn’s disease mucosa. Taken together this thesis shows that stress can modulate the uptake of luminal antigens and bacteria via the FAE, through mechanisms involving CRH and mast cells. It further shows that human ileal FAE is functionally distinct from VE, and that Crohn’s disease patients exhibit enhanced FAE permeability compared to inflammatory and non-inflammatory controls. This thesis presents novel insights into regulation of the FAE barrier, as well as into the pathophysiology of Crohn’s disease by demonstrating a previously unrecognised defect of the FAE barrier function in ileal Crohn’s disease.
Pietz, Grzegorz. "Innate immunity of human intestinal epithelium in childhood celiac disease : influences from celiac disease associated bacteria and dietary oats." Doctoral thesis, Umeå universitet, Institutionen för molekylärbiologi (Medicinska fakulteten), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-140691.
Повний текст джерелаDoctoral thesis
Daniel, Emeline. "Cytodiérèse des cellules épithetiales et maintien de l'intégrité du tissu chez Drosophila melanogaster." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B049/document.
Повний текст джерелаEpithelial cells are closely juxtaposed to form a tissue playing a physical and chemical barrier between external and internal body compartments. Thus, tissue integrity is essential. During development and adult life, epithelia has to growth and regenerate meaning a lot of divisions. At the end of cell division, cytokinesis occurs, implying the formation of a contractile ring which contracts to separate daughter cells. In Drosophila, once totally closed, the contractile ring gives rise to the midbody, just below adherens junctions, in the septate junctions layer. Last step of cytokinesis, abscission, permits the final cut and the cytoplasmic isolation of daughter cells. If cytokinesis is well described in isolated cells, little is known about epithelial cells cytokinesis. This work shows that whereas all abscission regulators and effectors are recruited, abscission is delayed in epithelial cells. KAEDE photo-conversion assays show that abscission is linked to epithelial cells mitosis entry. Then we investigate how permeability barrier is maintained during cell division. We show that neighboring cells present finger-like protrusions contacting the midbody all along the midbody is moving basally across septate junctions. FRAP experiments on bicellular and tricellular septate junctions show that they form just below adherens junctions and always above the midbody, leading to its basal migration. Contacts maintained with neighbors and polarized assembly of septate junctions participate to the maintenance of tissue integrity throughout epithelial cells divisions
Souza, Paula Cristina Torres de. "Padronização de novo método ex vivo para avaliação da permeabilidade intestinal de fármacos utilizando epitélio intestinal de rã-touro (Rana catesbeiana): comparação com células Caco-2." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/9/9139/tde-28082014-103309/.
Повний текст джерелаThere are lots of different in vitro technics in the literature using animal intestinal epithelium to estimate permeability of drugs, property that is an important parameter of bioavailabity. Considering that the main objective of Pharmaceutical Companies is the development of new drugs with good oral bioavailabity, the aim of this work was to standardize the permeability of antivirals using in vitro/ex vivo method of intestinal epithelium of Rana catesbeiana in Franz cells and compare these results to those obtained from studies using Caco-2 cells. Zidovudine and Acyclovir were selected as model drugs. The amount of drug permeated will be determined by the method of capillary electrophoresis for assays using Rana Catesbeiana and HPLC-UV for studies with Caco-2 cells. The permeation parameter determined was the apparent permeability coefficient (Papp) of drugs for both experimental models. To establish the experimental protocol to studies of intestinal permeability of frog, it was proposed a fractional 24-1 design with 4 additional tests using Minitab software and the variables were: intestinal section, pH of Ringer solution and temperature. The analysis of the experimental design made by the estimate of the regression parameters obtained from the factorial model results allowed the determination of the coefficients of the mathematical equation that defines the influence of the variables on the apparent permeability coefficient of acyclovir and zidovudine. The effects of pH and temperature interpreted jointly presented a slight interference, but the variables drug and intes tinal section interpreted together had major interference, showing greater permeation of drugs through the initial section of the intestine of the frog . The results of Papp were: for metoprolol, with the method of Caco-2 cells was 28 x 10-6 cm/s, a value which is consistent with other data of Caco-2 cells provided in the literature and the condition obtained with Franz cells that are most suitable for these and other results obtained from other techniques available in the literature, was 28.1 x 10-6 cm/s, provided with the final intestinal segment using frog epithelial membrane. In the case of acyclovir, the result of Papp of 0.48 x 10-6 cm/s obtained in one condition with final frog intestinal segment was exactly equal to the value of 0.48 x 10-6 cm/s, found with Caco-2 cells in the present study and are in agreement with other values available in the literature for Trapani and colegues, 2004 and also with Caco-2 cells. The Papp value for zidovudine obtained with the initial gut segment of frog, 13 x 10-6 cm /s was which more resembled that obtained by the technique of Caco-2 cells, 13.6 x 10-6 cm/s and is also consistent with other literature data.
Matysiak-Budnik, Tamara. "Helicobacter pylori et modifications de la perméabilité épithéliale gastrique." Bordeaux 2, 2000. http://www.theses.fr/2000BOR28767.
Повний текст джерелаDossou-Yovo, Flore. "Modification de la biodisponibilité orale des médicaments : interactions « Herb-Drugs » « Drugs- Drugs»." Thesis, Paris, CNAM, 2014. http://www.theses.fr/2014CNAM0936/document.
Повний текст джерелаOral dosing is still seen as the silver bullet of drug administration, as it is cheaper andbetter adapted to patient comfort. However, oral route is still inaccessible to many drugssuch as biologics and biosimilars respectively certain anticancer drugs and antiretrovirals(ARV).The aim of this present study was to find new drugs enhancers that improve the oralbioavailability of drugs and xenobiotics. All the studies were realized in vitro using Ussingchambers technic. To achieve the set objective we used the strategy to develop drugenhancer which can modulate at the same time transcellular and paracellular pathways.In the first part of this study (patent) we have shown that the use of a pharmaceutical and /or a dietetic formulation containing a plant extract (Hibiscus sabdariffa) could increase thebioavailability in vitro in rats not only of cisplatin (21 fold), oxaliplatin (11 fold) andFluorescein Isothiocyanate-Dextran 4000 (FD4, 3 fold). All that drugs were transportedthrough intestinal barrier using paracellular pathway. In addition the study showed thatthis formulated enhancer can increased the bioavailability of Efavirenz (7 fold) andAtazanavir (4 fold) which are active transported.In order to assess the effect of new drugs enhancer on mucus thickness that limits thetransport of xenobiotic through intestinal barrier, we decide to evaluate his effect on passiveand active transport of drugs.In the second part of this study we have shown that after a week of pre-treatment of ratswith Metronidazole (MTZ, publication 1) and Cotrimoxazole (CTX, publication 2), the twomost commonly used antibiotics in the prophylaxis against opportunistic infections in HIV /AIDS, both increase colonic mucus thickness that affect directly passive intestinalpermeability by reducing conductance an index of passive transport through intestinalepithelium. In addition those antibiotics also entail a change in the transepithelialconductance and ARV fluxes. After MTZ and CTX treatment the secretion of Atazanavir(ATZ) increases respectively in the proximal colon by 2 to 4 fold and in the distal colon by 3to 5 fold respectively. Ritonavir (RTV) is poorly absorbed in control, after a week of pretreatmentwith MTZ and CTX one rather notices a secretion of RTV 5 to 10 fold higher in theproximal and 2 to 5 fold higher in the distal colon. The next study will be conducted toevaluate the effect of new drugs enhancer on mucus thickness layer.In conclusion, oral bioavailability of drugs and xenobiotics can be enhanced bypharmaceutical composition that contains herbal extract which increase passive and activetransport of drugs through intestinal barrier
Motz, Stephan A. [Verfasser]. "Combined assessment of dissolution and epithelial permeability of solid oral dosage forms / von Stephan A. Motz." 2007. http://d-nb.info/983385645/34.
Повний текст джерелаHarvey, Benjamin Scott. "The effect of cannabinoids on cytokine evoked human colonic mucosal damage and Caco-2 epithelial permeability." Thesis, 2014. http://hdl.handle.net/2440/92814.
Повний текст джерелаThesis (Ph.D.) -- University of Adelaide, School of Medical Sciences, 2014
Khan, Niamat. "Comparative DNA‐Protein Interaction and Epithelial Tight Junctions Modulation Potential of Immunosuppressive Regime." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-86AB-B.
Повний текст джерелаSu, Kang-Cheng, and 蘇剛正. "Bile acids increase alveolar epithelial permeability via MAP kinase, cytosolic phospholipase A2, cyclooxygenase-2, PGE2, and junctional proteins." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/68972502580805930747.
Повний текст джерела國立陽明大學
急重症醫學研究所
101
Background and objective: Increasing evidence has shown that bile acid (BA) aspiration is associated with various lung diseases. The reaction of alveolar epithelium exposed to BAs is unknown. We hypothesize that BAs may induce alveolar permeability alteration and contribute to the pathogenesis of lung injury. Methods: Human alveolar epithelial cells were grown in monolayer and stimulated with a major component of BAs, chenodeoxycholic acid (CDCA). Transepithelial electrical resistance (TER) and paracellular fluxes were measured to assess permeability alteration. PGE2 production was measured, and its effect on TER and junctional proteins (JPs) was also examined. Reverse transcription-PCR and western blots were used to investigate the expression of mRNA and JPs. Results: CDCA induced significant p38 and JNK phosphorylation, cPLA2 and COX-2 mRNA expression, PGE2 production, TER reduction, and decay of JPs (including occludin, zonula occludens-1 [ZO-1], and E-cadherin, in which ZO-1 had maximal change). CDCA also increased paracellular fluxes, which was abolished by dexamethasone. Both CDCA and PGE2 contributed to TER reduction in an identical trend and a dose-response manner. PGE2 also reduced ZO-1 expression, which was similar to that observed by CDCA stimulation. Pretreatment with inhibitors of p38 (SB203580), JNK (SP600125), cPLA2 (mepacrine) and COX-2 (NS398) as well as dexamethasone reversed the CDCA-induced PGE2 production, TER reduction and decay of ZO-1. Conclusions: The increase in alveolar permeability was associated with decay of JPs.BAs may induce permeability alteration through the upregulation of MAPK, cPLA2, COX-2, PGE2 and JPs, which may contribute to the pathogenesis of BA-associated lung injury.
Baixinho, João Paulo Caseiro. "Development of curcumin lipid formulations for food applications: transport, permeability and safety evaluation on a mucus-secreting intestinal epithelial cell model." Master's thesis, 2018. http://hdl.handle.net/10362/52151.
Повний текст джерелаBanga, Amiraj. "Functional Effects of Carbon Nanoparticles on Barrier Epithelial Cell Function." 2012. http://hdl.handle.net/1805/2918.
Повний текст джерелаAs mass production of carbon nanoparticles (CNPs) continues to rise, the likelihood of occupational and environmental exposure raises the potential for exposure‐related health hazards. Although many groups have studied the effects of CNPs on biological systems, very few studies have examined the effects of exposure of cells, tissues or organisms to low, physiologically relevant concentrations of CNPs. Three of the most common types of CNPs are single wall nanotubes (SWNT), multi wall nanotubes (MWNT) and fullerenes (C60). We used electrophysiological techniques to test the effects of CNP exposure (40 μg/cm2 – 4 ng/cm2) on barrier function and hormonal responses of well characterized cell lines representing barrier epithelia from the kidney (mpkCCDcl4) and airways (Calu‐3). mpkCCDcl4 is a cell line representing principal cell type that lines the distal nephron in an electrically tight epithelia that aids in salt and water homeostasis and Calu‐3 is one of the few cell lines that produces features of a differentiated, functional human airway epithelium in vivo. These cell lines respond to hormones that regulate salt/water reabsorption (mpkCCDcl4) and chloride secretion (Calu‐3). In mpkCCDcl4 cells, after 48 hour exposure, the transepithelial electrical resistance (TEER) was unaffected by high concentrations (40 – 0.4 μg/cm2) of C60 or SWNT while lower, more relevant levels (< 0.04 μg/cm2) caused a decrease in TEER. MWNT decreased TEER at both high and low concentrations. CNT exposure for 48 hour did not change the transepithelial ion transport in response to anti‐diuretic hormone (ADH). In Calu‐3 cells, after 48 h of exposure to CNPs, fullerenes did not show any effect on TEER whereas the nanotubes significantly decreased TEER over a range of concentrations (4 μg/cm2‐0.004 ng/cm2). The ion transport response to epinephrine was also significantly decreased by the nanotubes but not by fullerenes. To look at the effect of exposure times, airway cells were exposed to same concentrations of CNPs for 24 and 1h. While the 48 h and 24 h exposures exhibited similar effects, there was no effect seen after 1h in terms of TEER or hormonal responses. In both the cell lines the magnitude of the transepithelial resistance change does not indicate a decrease in cellular viability but would be most consistent with more subtle changes (e.g., modifications of the cytoskeleton or changes in the composition of the cellular membrane). These changes in both the cell lines manifested as an inverse relationship with CNP concentration, were further corroborated by an inverse correlation between dose and changes in protein expression as indicated by proteomic analysis. These results indicate a functional impact of CNPs on epithelial cells at concentrations lower than have been previously studied and suggest caution with regard to increasing CNP levels due to increasing environmental pollution.
Mündörfer, Marco [Verfasser]. "Combined assessment of drug dissolution and epithelial permeability : implementation of online TEER measurement and extension to BCS class III and IV compounds / von Marco Mündörfer." 2010. http://d-nb.info/1009514245/34.
Повний текст джерелаLi, Pin. "Effects of carbon nanotubes on airway epithelial cells and model lipid bilayers : proteomic and biophysical studies." Thesis, 2014. http://hdl.handle.net/1805/5968.
Повний текст джерелаCarbon nanomaterials are widely produced and used in industry, medicine and scientific research. To examine the impact of exposure to nanoparticles on human health, the human airway epithelial cell line, Calu-3, was used to evaluate changes in the cellular proteome that could account for alterations in cellular function of airway epithelia after 24 h exposure to 10 μg/mL and 100 ng/mL of two common carbon nanoparticles, singleand multi-wall carbon nanotubes (SWCNT, MWCNT). After exposure to the nanoparticles, label-free quantitative mass spectrometry (LFQMS) was used to study differential protein expression. Ingenuity Pathway Analysis (IPA) was used to conduct a bioinformatics analysis of proteins identified by LFQMS. Interestingly, after exposure to a high concentration (10 μg/mL; 0.4 μg/cm2) of MWCNT or SWCNT, only 8 and 13 proteins, respectively, exhibited changes in abundance. In contrast, the abundance of hundreds of proteins was altered in response to a low concentration (100 ng/mL; 4 ng/cm2) of either CNT. Of the 281 and 282 proteins that were significantly altered in response to MWCNT or SWCNT, respectively, 231 proteins were the same. Bioinformatic analyses found that the proteins common to both kinds of nanotubes are associated with the cellular functions of cell death and survival, cell-to-cell signaling and interaction, cellular assembly and organization, cellular growth and proliferation, infectious disease, molecular transport and protein synthesis. The decrease in expression of the majority proteins suggests a general stress response to protect cells. The STRING database was used to analyze the various functional protein networks. Interestingly, some proteins like cadherin 1 (CDH1), signal transducer and activator of transcription 1 (STAT1), junction plakoglobin (JUP), and apoptosis-associated speck-like protein containing a CARD (PYCARD), appear in several functional categories and tend to be in the center of the networks. This central positioning suggests they may play important roles in multiple cellular functions and activities that are altered in response to carbon nanotube exposure. To examine the effect of nanotubes on the plasma membrane, we investigated the interaction of short purified MWCNT with model lipid membranes using a planar bilayer workstation. Bilayer lipid membranes were synthesized using neutral 1, 2-diphytanoylsn-glycero-3-phosphocholine (DPhPC) in 1 M KCl. The ion channel model protein, Gramicidin A (gA), was incorporated into the bilayers and used to measure the effect of MWCNT on ion transport. The opening and closing of ion channels, amplitude of current, and open probability and lifetime of ion channels were measured and analyzed by Clampfit. The presence of an intermediate concentration of MWCNT (2 μg/ml) could be related to a statistically significant decrease of the open probability and lifetime of gA channels. The proteomic studies revealed changes in response to CNT exposure. An analysis of the changes using multiple databases revealed alterations in pathways, which were consistent with the physiological changes that were observed in cultured cells exposed to very low concentrations of CNT. The physiological changes included the break down of the barrier function and the inhibition of the mucocillary clearance, both of which could increase the risk of CNT’s toxicity to human health. The biophysical studies indicate MWCNTs have an effect on single channel kinetics of Gramicidin A model cation channel. These changes are consistent with the inhibitory effect of nanoparticles on hormone stimulated transepithelial ion flux, but additional experiments will be necessary to substantiate this correlation.
Phillips, Brett E. "Occludin regulates permeability and cell division in retinal pigmented epithelium cells." 2007. http://www.etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-1853/index.html.
Повний текст джерелаHan, Taishien, and 韓台賢. "Effects of Clematis Armandi extracts on permeability and short circuit current (Isc) across frog skin epithelium." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/28797961243720219679.
Повний текст джерела國立中山大學
生物科學系研究所
90
Summary Clmatis Armandi has been used frequently in traditional Chinese medicine for the treatment of diuretic symptoms. The mechanism of its action is unclear. Possible action of this substance may involve alternation of electrolyte transport through the epithelia membranes. In this study,transepithelial conductance of frog skin was measured in vitro in voltage-clamped Ussing chambers. Adding Clematis Armandi extracts to apical surface induced a conductance increment of 1.21 μS and an apical to serosal Isc of 28.78 μA/cm2. The Isc can not be completely blocked by apical application of amiloride. Nifedipine and TEA had no effect on Clematis Armandi induced Isc decrease. These data indicate that frog skin is highly responsive to the concentrated Clematis Armandi extracts. The increase in Isc reflects changes in transepithelial transport of Na+ ions modulated at apical membrane. The enormous increase in transepithelial conductance suggests that in additional to enhancement of amiloride-sensitive Na+ channels, Clematis Armandi may also modulate other pathways, such as Cl- ion channel modulation, which needs further investigation.
Lin, Zhe-Wei, and 林哲瑋. "Effect of Rhei Rhizoma Extract on Short-circuit Current and Ion Permeability Across the Frog Skin Epithelium." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/aezuw6.
Повний текст джерела國立中山大學
生物科學系研究所
97
Rhei Rhizoma, also named as rhubarb or Da Huang, has been used widely in oriental traditional medicine in treating constipation and edema. However, though much affection has been paid to the make of components on pharmaceutical mechanisms, few studies have been conducted to reveal chemical and physical mechanism of these effects. Studies have shown that diarrhea causes imbalance of chloride and sodium ion movements via epithelium, we wondered if similar mechanism may apply to Rhei Rhizoma, a herbal drug which has been used to treat constipation in oriental medicine for thousands of years. The measurement of short-circuit current (Isc) has been used widely to estimate the ion transportation between mucosal and serosal side of epithelium. In this study, we used Ussing chamber technique to examine the alternation in membrane potential and short-circuit currents. The result shows, at default, the Isc of frog skin we used was at 59.23±5.58μA/cm², and the conductance was at 1.11±0.50μA/cm²•mV. The lnjection of 1ml RRE to mucosal side of the frog skin leaded to a 90% elevation of the Isc. Followed by the application of Amiloride (sodium channel inhibitor) and Chlorothiazide (chloride channel inhibitor) to mucosal side of the epithelial skin, the observed Isc were then reduced 136% and 33% respectively. If RRE were applied after the adding of Amiloride or Chlorothiazide to the frog skin, then the Isc of the skin elevated only 24% and 70% respectively. These results show that Rhei Rhizoma Extract (RRE) significantly increases Isc upon application to the mucosal side of the skin epithelium. Amiloride and Chlorothiazide will both inhibit the Isc induced by RRE, indicating activation of chloride channel and Amiloride-sensitive sodium channel of the epithelial tissue by RRE. After the regular Ringer solution used in the preparation was replaced by Na-free and Cl-free Ringer solution, the inhibition of Isc by RRE application could still be observed although the inhibition was trivia. These results indicate that RRE acts dominantly on mucosa side of the epithelium and can be used to enhance sodium transport and to stimulate the secretion of Cl- in the epithelium.
Su, Hsuan-yin, and 蘇宣穎. "EFFECTS OF PORIA COCOS WOLF EXTRACT (PCWE) ON SHORT-CIRCUIT CURRENT AND ION PERMEABILITY ACROSS THE EPITHELIUM OF PIG COLON." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/ghar46.
Повний текст джерела國立中山大學
生物科學系研究所
95
PCWE has been used widely in oriental traditional medicine in treating edema and diarrhea. Recent studies have shown that PCWE may also have anti-tumor and anti-inflammation acts. However, few studies have been conducted to reveal the mechanisms of these effects. In the present study, we tried to elucidate the mechanisms by investigating the effects on PCWE on the regulation of ion transport across the epithelial membranes of colon, which is also useful in explaining the anti-diarrhea and anti-edema effects. Alternation in membrane potential and short-circuit current (Isc) were examined using the Ussing chamber technique. Our results showed that PCWE decreased Isc upon application to the apical side. Amiloride inhibited this Isc induced by PCWE indicating that PCWE acted on amiloride-sensitive sodium channel of the epithelium. However, when PCWE was applied to the serosal side, the Isc was not changed, indicating a minimal influence of this substance on ATP-driving Na+/K+ counter transporters. Our data also showed that the Isc decreased by PCWE could be inhibited by bumetanide and chlorothiazide (Cl‾ channel inhibitors). We therefore concluded that PCWE could both enhance sodium transport and stimulate the secretion of Cl‾ in colon epithelium.
McCanna, David. "Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic Products." Thesis, 2009. http://hdl.handle.net/10012/4338.
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