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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Induction of glioma stem cells by interleukin-1beta and transforming growth factor-beta

Liu, Ziyan January 1900 (has links)
Master of Science / Department of Anatomy and Physiology / Lei Wang / Jishu Shi / Transforming growth factor beta (TGF-β) and interleukin-1β (IL-1β) are both up-regulated in high grade gliomas and their elevated activities have been associated with prognosis in glioma patients. It is known that TGF-β is involved in proliferation and maintenance of glioma stem cells. In this study, I evaluated whether IL-1β also plays an important role in glioma stem cell development. Glioma stem cells are usually identified by using a sphere assay where glioma stem cells proliferate as neurospheres in serum free medium (SFM) in the presence of two growth factors: EGF and bFGF. However, LN229, a human glioblastoma cell line does not form neurospheres in SFM, suggesting that LN229 cells contain very few stem cells. I found that combination of IL-1β and TGF-β, but not IL-1β or TGF-β alone induced LN229 cells to grow as neurospheres in SFM. Furthermore, quantitative RT-PCR analyses show that the expression of stem cell markers (Nestin, Bmi1, Notch2, and LIF), cytokines (IL-1β, IL-6 and IL-8) and invasive genes (SIP1, β-integrin and N-Cadherin) are significantly enhanced in IL-1β /TGF-β induced spheres compared to the control. Using an invasion assay, drug resistance test, and colony assay, I found that LN229 sphere cells induced by IL-1β and TGF-β are more invasive, have increased drug resistant ability, and are more oncogenic in comparison to the control. Together, these results suggest that IL-1β cooperates with TGF-β to induce glioma stem-like cell phenotype.
2

Synthetic studies related to caspase inhibitors

Coue, Annie January 2000 (has links)
No description available.
3

The role of caspase-1 and interleukin-1 ss [beta] in amyotrophic lateral sclerosis

Molawi, Kaaweh January 2009 (has links)
Zugl.: Berlin, Humboldt-Univ., Diss., 2009
4

Interleukin-1 beta promotes epithelial-mesenchymal transition and a stem cell phenotype of colon cancer cells via Zeb1/2

Li, Yijing January 1900 (has links)
Master of Science / Department of Anatomy and Physiology / Lei Wang / Jishu Shi / Interleukin-1 beta (IL-1β) is an important mediator of inflammatory response, and the elevated expression of IL-1β is correlated with tumor growth and metastasis. Epithelial-mesenchymal transition (EMT) is a reversible transition between epithelial phenotype and mesenchymal phenotype. Usually, EMT can be identified by its unique morphology change and expression of EMT markers. In our study, we have found after treated HCT-116, a colon cancer cell line, and human primary colon cancer cells with IL-1β, cells began to display mesenchymal phenotype with highly down-regulated E-cadherin expression and up-regulated ZEB factors expression. For colon cancer cells, sphere formation assay in serum free medium (SFM) with the presence of growth factors is used to identify cancer stem cell population. We have shown that IL-1β can induce colon cancer stem cell proliferation and express stem cell markers (Bmi1, Nanog, and Nestin). In addition, besides the stem cell markers, we also found ZEB factors were highly up-regulated in spheroid cells as well. We silenced Zeb1 expression and investigated the effect of IL-1β on shZeb1 HCT-116 cells. The results indicated Zeb1 knockdown not only inhibited IL-1β-induced EMT but also reduced proliferation of spheroid cells and inhibited Bmi1 expression. Therefore, ZEB factors must play an important role in both EMT process and cancer stem cell development. From our data, we conclude that IL-1β promotes epithelial-mesenchymal transition and a stem cell phenotype in colon cancer via ZEB factors.
5

Genetic variations in the NALP3 inflammasome: a susceptibility factor for inflammatory diseases

Verma, Deepti January 2009 (has links)
<p>Innate immunity has received impressive attention in the past decade owing to the discovery of the Toll like receptors (TLRs) and the NOD-like receptors (NLRs). While the TLRs specialize in fighting microbes at the cell surface, the NLRs complement by detecting and responding to intracellular microbes. Recently, the non-microbe sensing NLR called inflammasomes, have been identified, which senses metabolic stress as well as certain pathogenic microbes and elicits host’s inflammatory response. <strong></strong></p><p>The NLR, NALP3 (formerly known as cryopyrin) forms a large cytoplasmic complex called the ‘inflammasome’ when NALP3, activated by a stimuli, associates with the adaptor proteins ASC and CARD-8. This interaction leads to the activation of pro-inflammatory caspase-1 which subsequently results in the formation of Interleukin (IL)-1β and IL-18. Mutations in the gene encoding NALP3, termed <em>NLRP3</em> can lead to its constitutive activation resulting in an uncontrolled production of IL-1β. These mutations have been implicated in hereditary inflammatory diseases, often grouped under cryopyrin associated periodic syndromes (CAPS).</p><p>This thesis describes a patient with a long history of arthritis and antibiotic resistant fever, but without the typical symptoms of CAPS. The patient was found to be a heterozygous carrier of two common polymorphisms Q705K in <em>NLRP3 </em>and C10X in the <em>CARD-8</em>. Experimental studies showed elevated levels of caspase-1 and IL-1β in the patient, and a total clinical remission was achieved by IL-1β blockade. These two polymorphisms combined, were found to occur in approximately 4% of the control population, suggesting the possibility of a genetic predisposition for inflammation in these individuals. Therefore, a cohort of rheumatoid arthritis (RA) patients, where elevated IL-1β could be one of the reasons behind chronic inflammation, was investigated. We found that carrying the combined polymorphisms resulted in increased RA susceptibility and a more severe disease course. Hypothetically, this subgroup of patients might benefit from IL-1β blockade. Additional studies are warranted to elucidate the functional effects of the two polymorphisms and to determine whether they identify a subgroup of patients that could benefit from IL-1 targeted therapy. Given the structural similarity of NALP3 to other NALPs, the possibility of involvement of the alternative, homologous genes cannot be eliminated.</p>
6

The effect of glibenclamide on the pathogenesis of melioidosis

Koh, Gavin Christian Kia Wee January 2012 (has links)
Melioidosis is an important cause of community-acquired sepsis, endemic to Southeast Asia and Northern Australia. Melioidosis is caused by the soil saprophyte, Burkholderia pseudomallei, a motile Gram-negative bacillus, and is associated with a mortality rate that approaches 50% in Northeast Thailand. The most important risk factor for melioidosis is diabetes mellitus, and two-thirds of all adult patients with melioidosis have diabetes as a risk factor. It has been noted previously, however, that patients with diabetes have lower mortality than patients without diabetes. In this dissertation, we look at a cohort of 1160 consecutive adult melioidosis patients presenting to Sappasithiprasong Hospital in Ubon Ratchathani, Thailand, 410 (35%) of whom were diagnosed with diabetes prior to admission. We confirmed previous findings that diabetes protected from mortality in melioidosis, but also found that this protective effect was confined to a smaller subset of patients (208 patients) who were treated with glibenclamide prior to admission. Patients with hyperglycaemia (but no diagnosis of diabetes prior to admission) had the same mortality rate as patients without diabetes. In vitro experiments found no inhibitory effect of glibenclamide on bacterial growth, and we therefore looked for evidence of an effect of glibenclamide on the host. We conducted a gene expression study of circulating blood leukocytes in melioidosis patients and compared them to uninfected controls. In this study, we found that glibenclamide was associated with an anti-inflammatory effect on the host response to melioidosis. To further elucidate a mechanism for the action of glibenclamide, we studied the effect of glibenclamide therapy in a mouse model of melioidosis and found that the effect of glibenclamide was specific to interleukin-1β secretion. This reduction in interleukin-1β secretion was associated with reduced cellular influx into the lungs as well as lower bacterial loads in blood, liver and spleen.
7

Resveratrol Counteracts IL-1β-mediated Impairment of Extracellular Matrix Deposition in 3D Articular Chondrocyte Constructs / Resveratrol wirkt der IL-1β-vermittelten Beeinträchtigung von Extrazellulärmatrix-Deposition in 3D Konstrukten aus artikulären Chondrozyten entgegen

Frischholz, Sebastian January 2021 (has links) (PDF)
Articular cartilage is an exceptional connective tissue which by a network of fibrillar collagen and glycosaminoglycan (GAG) molecules allows both low- friction articulation and distribution of loads to the subchondral bone (Armiento et al., 2018, Ulrich-Vinther et al., 2003). Because of its very limited ability to self-repair, chondral defects following traumatic injury increase the risk for secondary osteoarthritis (OA) (Muthuri et al., 2011). Still, current OA treatments such as common nonsteroidal anti-inflammatory drugs (NSAIDs) and joint replacement primarily address end-stage symptoms (Tonge et al., 2014). As low-grade inflammation plays a pivotal role in the pathogenesis of OA (Robinson et al., 2016), there is a strong demand for novel therapeutic concepts, such as integrating application of anti-inflammatory agents into cartilage cell- based therapies in order to effectively treat OA affected joints in early disease stages. The polyphenolic phytoalexin resveratrol (RSV), found in the skin of red grapes, berries, and peanuts, has been shown to have effective anti-inflammatory properties (Shen et al., 2012). However, its long-term effects on 3D chondrocyte constructs cultured in an inflammatory environment with regard to tissue quality have remained unexplored so far. Therefore, in this study, pellets made from expanded porcine articular chondrocytes were cultured for 14 days with either the pro-inflammatory cytokine interleukin-1β (IL-1β) (1 - 10 ng/ml) or RSV (50 μM) alone, or a co-treatment with both agents. Constructs treated with chondrocyte medium only served as control. Treatment with IL-1β at 10 ng/ml resulted in a significantly smaller pellet size and reduced DNA content. However, RSV counteracted the IL-1β-induced decrease and significantly enhanced diameter and DNA content. Also, in terms of GAG deposition, treatment with IL-1β at 10 ng/ml resulted in a tremendous depletion of absolute GAG content and GAG/DNA. Again, RSV co-treatment counteracted the inflammatory stimulus and led to a partial recovery of GAG content. Histological analysis utilizing safranin-O staining confirmed these findings. Marked expression of the cartilage-degrading enzyme matrix metalloproteinase 13 (MMP13) was detected in IL-1β-treated pellets, but none upon RSV co- treatment. Moreover, co-treatment of IL-1β-challenged constructs with RSV significantly increased absolute collagen content. However, under non- inflammatory conditions, RSV induced gene expression and protein accumulation of collagen type X, a marker for undesirable hypertrophy. Taken together, in the present thesis, RSV was demonstrated to elicit marked beneficial effects on the extracellular matrix composition of 3D cartilaginous constructs in long-term inflammatory culture in vitro, but also induced hypertrophy under non-inflammatory conditions. Based on these findings, further experiments examining multiple concentrations of RSV under various inflammatory conditions appear desirable concerning potential therapeutic applicability in OA. / Gelenkknorpel ermöglicht als spezielles Bindegewebe aus Kollagenfasern und Glykosaminoglykanen (GAG) sowohl die reibungsarme Beweglichkeit in Gelenken als auch die Lastübertragung auf angrenzende Knochen (Armiento et al., 2018, Ulrich-Vinther et al., 2003). Aufgrund der sehr begrenzten Fähigkeit zur intrinsischen Erneuerung erhöhen chondrale Defekte nach traumatischen Verletzungen das Risiko für sekundäre Arthrose (Osteoarthritis; OA) (Muthuri et al., 2011). Dennoch konzentrieren sich derzeitige Behandlungsansätze, einschließlich nichtsteroidaler Antirheumatika (NSAR) und des operativen Gelenkersatzes, hauptsächlich auf Symptome im Endstadium der Erkrankung (Tonge et al., 2014). Da eine geringgradige Entzündung eine entscheidende Rolle in der Pathogenese der Arthrose spielt (Robinson et al., 2016), besteht ein starker Bedarf an neuartigen Therapiekonzepten, wie der Kombination von anti- inflammatorischen Wirkstoffen mit knorpelzellbasierten Therapien, um von Arthrose betroffene Gelenke in frühen Krankheitsstadien wirksam zu behandeln. Das polyphenolische Phytoalexin Resveratrol (RSV), welches in der Schale roter Weintrauben, in Beeren und Erdnüssen vorkommt, besitzt starke entzündungshemmende Eigenschaften (Shen et al., 2012). Langzeiteffekte auf 3D-Knorpelkonstrukte unter inflammatorischen Bedingungen sind hinsichtlich der Gewebequalität jedoch bislang unerforscht geblieben. Daher wurden in der vorliegenden Studie Pellets aus expandierten porcinen Gelenkknorpelzellen über einen Zeitraum von 14 Tagen entweder mit dem pro-inflammatorischen Zytokin Interleukin-1β (IL-1β) (1 - 10 ng/ml) oder RSV (50 μM) allein, oder mit beiden Agenzien kombiniert behandelt. Konstrukte, welche nur serumfreies Chondrozytenmedium erhielten, dienten als Kontrolle. Die Behandlung mit IL- 1β in einer Konzentration von 10 ng/ml führte zu einem signifikant geringeren Durchmesser der Pellets sowie einem verringerten DNA-Gehalt. RSV wirkte dieser IL-1β-vermittelten Reduktion entgegen und steigerte signifikant sowohl Durchmesser als auch DNA-Gehalt der untersuchten Konstrukte. Auch in Bezug auf die Deposition von GAG-Molekülen führte die Kultur mit IL-1β (10 ng/ml) zu einer massiven Abnahme des absoluten GAG-Gehaltes und der GAG/DNA- Ratio. Abermals wirkte die gleichzeitige Behandlung mit RSV dem Entzündungsreiz deutlich entgegen und resultierte in einer partiellen Wiederherstellung des GAG-Gehaltes. Die histologische Analyse unter Verwendung von Safranin-O-Färbungen bestätigte diese Ergebnisse. Darüber hinaus manifestierte sich eine ausgeprägte Expression des knorpelabbauenden Enzyms Matrix-Metalloproteinase 13 (MMP13) in IL-1β behandelten Pellets, nicht jedoch in denen, die simultan mit RSV behandelt wurden. Außerdem resultierte die gleichzeitige Behandlung von IL-1β-stimulierten Konstrukten mit RSV in einer signifikanten Erhöhung des absoluten Kollagengehaltes. Unter nicht-inflammatorischen Bedingungen induzierte RSV die Genexpression und Proteinakkumulation von Kollagen Typ X, einem Marker für unerwünschte Hypertrophie. Zusammengefasst wurde in der vorliegenden Arbeit gezeigt, dass RSV deutliche positive Effekte auf die Extrazellulärmatrix von 3D- Knorpelkonstrukten in einer Langzeit-Entzündungskultur in vitro hervorruft, allerdings unter nicht-inflammatorischen Bedingungen Hypertrophie induziert. Basierend auf diesen Befunden erscheinen weitere Experimente zur Untersuchung unterschiedlicher RSV-Konzentrationen unter verschiedenen Entzündungsbedingungen hinsichtlich einer möglichen therapeutischen Anwendbarkeit bei OA wünschenswert.
8

Genetic variations in the NALP3 inflammasome: a susceptibility factor for inflammatory diseases

Verma, Deepti January 2009 (has links)
Innate immunity has received impressive attention in the past decade owing to the discovery of the Toll like receptors (TLRs) and the NOD-like receptors (NLRs). While the TLRs specialize in fighting microbes at the cell surface, the NLRs complement by detecting and responding to intracellular microbes. Recently, the non-microbe sensing NLR called inflammasomes, have been identified, which senses metabolic stress as well as certain pathogenic microbes and elicits host’s inflammatory response. The NLR, NALP3 (formerly known as cryopyrin) forms a large cytoplasmic complex called the ‘inflammasome’ when NALP3, activated by a stimuli, associates with the adaptor proteins ASC and CARD-8. This interaction leads to the activation of pro-inflammatory caspase-1 which subsequently results in the formation of Interleukin (IL)-1β and IL-18. Mutations in the gene encoding NALP3, termed NLRP3 can lead to its constitutive activation resulting in an uncontrolled production of IL-1β. These mutations have been implicated in hereditary inflammatory diseases, often grouped under cryopyrin associated periodic syndromes (CAPS). This thesis describes a patient with a long history of arthritis and antibiotic resistant fever, but without the typical symptoms of CAPS. The patient was found to be a heterozygous carrier of two common polymorphisms Q705K in NLRP3 and C10X in the CARD-8. Experimental studies showed elevated levels of caspase-1 and IL-1β in the patient, and a total clinical remission was achieved by IL-1β blockade. These two polymorphisms combined, were found to occur in approximately 4% of the control population, suggesting the possibility of a genetic predisposition for inflammation in these individuals. Therefore, a cohort of rheumatoid arthritis (RA) patients, where elevated IL-1β could be one of the reasons behind chronic inflammation, was investigated. We found that carrying the combined polymorphisms resulted in increased RA susceptibility and a more severe disease course. Hypothetically, this subgroup of patients might benefit from IL-1β blockade. Additional studies are warranted to elucidate the functional effects of the two polymorphisms and to determine whether they identify a subgroup of patients that could benefit from IL-1 targeted therapy. Given the structural similarity of NALP3 to other NALPs, the possibility of involvement of the alternative, homologous genes cannot be eliminated.
9

Therapeutisches Potential der IL-1ß-Neutralisierung nach Schädel-Hirn-Trauma - eine präklinische randomisierte Kontrollstudie / The therapeutic potential of interleukin 1 beta neutralisation treating Traumatic Brain injury - A preclinical randomised control study

Stollburges, Elisa January 2024 (has links) (PDF)
Durch die Interleukin 1ß Neutralisierung mittels eines Antikörpers soll versucht werden, das Outcome nach einem Schädelhirntrauma zu verbessern und den erlittenen Schaden zu minimieren / With the support of antibodies, interleukin 1 beta neutralisation attempts to improve the outcome after suffering from a traumatic brain injury and to limit the damage suffered
10

Der Einfluss proinflammatorischer Cytokine (TNF-alpha und IL-1 beta) auf die Mechanik und Energetik in humanem Myokard / The effect of proinflammatory cytokines TNF-alpha and IL-1 beta on economy of contraction in human myocardium

Heuer, Stefan Matthias January 2007 (has links) (PDF)
Die proinflammatorischen Cytokine TNF-alpha und IL-1 beta werden im Myokard bei akuter und chronischer Herzinsuffizienz sezerniert. Ihr negativer Einfluß auf Inotropie und Kontraktionsökonomie des Myokards wurde in zahlreichen In-Vitro und Tiermodellen nachgewiesen. Bisherige Versuche einer therapeutischen Intervention in klinischen Studien waren trotz guter Erfolge in Tiermodellen bislang erfolglos. Um diese Diskrepanz zu untersuchen wurden erstmals Messungen der Kontraktilität und Kontraktionsökonomie an humanem Myokard durchgeführt. Weiterhin wurden Untersuchungen bezüglich der postulierten Signaltransduktion mittels der Sphingomyelinaseaktivität Ergebnisse Sowohl TNF-alpha; als auch IL-1&#61538; zeigen übereinstimmend mit In-Vitro Versuchen an nicht-humanem Myokard eine deutlich Minderung der Kontraktilität und Steigerung des kontraktionsabhängigen Sauerstoffverbrauchs. IL-beta führt darüber hinaus zu einer erhöhten diastolischen Kraft. Die Relaxationsgeschwindigkeit wird nicht beeinträchtigt. Glutathion vermindert diese Effekte in 10 molarer Konzentration fast vollständig. Eine Steigerung der Aktivität der neutralen oder sauren Sphingomyelinase kann nicht als Bestandteil der Signaltransduktion bestätigt werden. Schlussfolgerung Alleinig auf TNF-alpha zielende Therapieansätze inhibieren die negativen Einflüsse von Cytokinen im ischämischen und postischämischen Myokard nicht ausreichend. Glutathionapplikation kann TNF-alpha und IL-beta Effekte auf das Myokard inhibieren. / The proinflammatory cytokines TNF-a and IL-1b impair economy of contraction in human myocardium TNF-alpha and IL-1beta impair myocardial function in different animal species and in human myocardium. Prospective clinical trials studying TNF-a antagonists in patients with chronic heart failure failed to show a benefit. Therefore reasons for this possibly species-related discrepancy are to be examined. In the present study TNF-alpha and IL-1beta not only reveal an immediate negative inotropic effect but increase specific oxygen demand in human right atrial myocardium. Enhanced oxygen consumption was not caused by an elevated basal metabolism but an impaired economy of contraction. Furthermore, glutathione is able to inhibit the effect of both cytokines. The results suggest that proinflammatory cytokines have a considerable effect on myocardial mechano-energetic parameters in human myocardium as well. The sole inhibition of TNF-a as it was done in recent clinical trials does not seem prospectful.

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