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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.
221

Transaldolase 1 is required for Neutrophil Extracellular Trap (NET) Formation

Morath, Jakob Paul 12 June 2020 (has links)
Transaldolase-Mangel (TALDO) ist ein extrem seltener, angeborener Stoffwechseldefekt, von dem weltweit nur 34 Fälle bekannt sind. Der Defekt geht auf den Verlust des Enzyms Transaldolase 1 aus dem nicht-oxidativen Pentosephosphat-Weg (nicht-oxPPW) zurück und äußert sich in einem weiten Spektrum klinischer Symptome. Die schwerwiegendsten Folgen sind Leber- und Nierenmangelfunktionen, die zum sehr frühen Tod führen können. Desweiteren leiden 15 % der Patienten an wiederkehrenden Infektionen. Neutrophile Granulozyten (Neutrophile) sind die häufigsten weißen Blutkörperchen im Menschen und essentiell für die angeborene Immunantwort gegen Infektionserreger. Ich habe hier funktionale Aspekte von TALDO-Neutrophilen untersucht. Der oxidative Pentosephosphat-Weg (oxPPW) stellt das Reduktionsäquivalent NADPH bereit, welches indirekt für die Entstehung von reactive oxygen species (ROS)-abhängigen Neutrophil Extracellular Traps (NETs) verantwortlich ist. Der Beitrag des nicht-oxPPW zur ROS-abhängigen NET-Bildung ist bislang nicht bekannt. In dieser Arbeit konnte ich für Neutrophile aus drei TALDO-Patienten eine jeweils komplett abwesende Entstehung ROS-abhängiger NETs und einen deutlich verringerten oxidativen Burst nach PMA-Stimulation zeigen. Um diese Beobachtungen in einem unabhängigen Modelsystem zu bestätigen, habe ich mit Hilfe des CRISPR-Cas9-Systems, ‚knock-out‘ Mutanten von Transaldolase 1 und dessen Partnerenzym Transketolase in der Neutrophil-ähnlichen Zelllinie PLB-985 hergestellt. Die dergestalt genetisch manipulierten Zellen waren nicht mehr zu PMA-induziertem Zelltod in der Lage. Dies ist somit der erste genetische Beweis für die Abhängigkeit des oxidativen Burst und der Bildung von NETs vom nicht-oxPPW. Diese Erkenntnis trägt zum einen zum mechanistischen Verständnis der NET-Entstehung bei und liefert zum anderen eine potentielle Erklärung für einige der bei TALDO beobachteten Symptome. Desweiteren wurden einige der metabolischen Erfordernisse für die Bildung von NETs mit Hilfe von Inhibitoren untersucht. Die erhaltenen Erkenntnisse zeigen, dass das initiale Maximum des oxidativen Bursts für NET-Bildung unerheblich ist und vielmehr die ROS-Generierung nach ca. 50 Minuten entscheidende Bedeutung für diese hat. / Transdaldolase 1-deficiency (TALDO) is a rare genetic disease with only 34 described cases globally. Transaldolase 1 is part of the non-oxidative pentose phosphate pathway (PPP) and its deficiency results in many clinical symptoms including kidney and liver failure, which can lead to early child-mortality. Some of these patients suffer from recurrent infections, for example in the respiratory tract. Neutrophils are the most abundant white blood cells and essential for the innate immune defence against bacterial and fungal pathogens. The PPP generates reduced NADPH that is crucial for the generation of superoxide by the NADPH oxidase NOX2. In turn, NOX2 is essential for neutrophil extracellular trap (NET) formation. NETs occur through the neutrophil-specific cell death netosis and consist of chromatin decorated with granular proteins. Here I report that neutrophils of three TALDO patients did not make NETs. Deletion of transaldolase 1, and its partner enzyme transketolase, in the neutrophil-like PLB-985 cell line reduced ROS generation and cell death. This confirms that transaldolase 1 is required for NET formation. We present, to the best of our knowledge, the first genetic evidence that the non-oxidative PPP is required for ROS generation and NET formation. Furthermore, some of the metabolic requirements for NET formation were assessed. The obtained data indicate that the initial peak of the oxidative burst is irrelevant for NET formation but the ROS generation after 50 minutes on the contrary has crucial significance.
222

Successful Treatment of Autoimmune Neutropenia With Recombinant Human Granulocyte-Colony Stimulating Factor (R-metHuG-CSF)

Krishnan, K., Ross, C. W., Bockenstedt, P. L., Adams, P. T. 01 January 1997 (has links)
Autoimmune neutropenia (AIN) is characterized by antibody mediated peripheral destruction of neutrophils. Since there is no effective treatment, antibiotics have to be used frequently for recurrent infections. Five selected patients with serologically proven AIN were treated with r-metHuG- CSF at 5-8 μg/kg body weight (300-480 μg) daily: the dose and frequency of r-metHuG-CSF was reduced after neutrophil counts above 1.0 x 109/l were obtained. R-metHuG-CSF is effective in AIN and causes a sustained rise in ANC which can he maintained on a low dose administered twice or thrice weekly.
223

The effects of neutrophil elastase on abnormal calcification in soft tissues

Wang, Dingxun 29 January 2022 (has links)
BACKGROUND: Calcification is a natural process of bone formation or osteogenesis. However, calcium is able to be deposited abnormally in soft tissues such as the aorta, adipose tissue and liver, causing these to harden. Abnormal calcification in arteries is a common factor contributing to high blood pressure and, further, many severe cardiovascular diseases such as atherosclerosis and coronary disease. In liver and adipose tissue, calcification always takes place accompanied by excess extracellular matrix (ECM) accumulation which is called fibrosis, contributing to cirrhosis and metabolic disorders including insulin resistance. In addition, it is documented that severe calcification in adipose tissues is able to cause damage to the micro-vascular system, and calcification in perivascular adipose tissue (PVAT) is a key effector of arterial stiffness. Dystrophic calcification, one of the most common types of abnormal calcification, usually occurs as a reaction to tissue damage such as obesity-induced inflammation. Increasing numbers of studies indicate that abnormal calcification is the result of re-differentiation towards osteogenesis which occurs in the nascent resident cells under the stimulation of multiple factors. The BMP/Smad signaling pathway is commonly known to participate in bone formation and is implicated in mineralization as well as local induction of inflammation. Importantly, BMP/Smad signaling as an inducer of the osteochondrogenic phenotype in vascular calcification is fully appreciated. However, the molecular events of dystrophic calcification triggered by obesity-induced chronic inflammation still remain unclear. Our previous studies have identified that imbalance with increased activity of neutrophil elastase (NE), a Ser protease mainly released by neutrophils during inflammation, and decreased serum levels of the NE inhibitor α1-antitrypsin A1AT, contributes to the development of obesity-related metabolic complications including insulin resistance, fatty liver and chronic inflammation. This study explored the effects of NE on abnormal calcification in soft tissues, which may be mediated by BMP/Smad signaling pathway, and, furthermore, the molecular mechanism by which NE activates the BMP/Smad signaling pathway. METHODS: Wild-type mice were fed with either a high-fat high-fructose diet (HFHFD), a high-fat diet (HFD) alone or a normal chow diet (NCD), and NE-knockdown mice were fed with a HFHFD. Adipose tissue and liver were extracted from all mice. H&E staining and immunofluorescence staining (IF) detected the inflammation condition. Alizarin staining and von kossa staining were used to detect calcium deposits. 3,3′-Diaminobenzidine (DAB) staining was used to examine active phospho-Smad1/5 signaling. Regarding nascent resident cells which have potential ability of osteogenic re-differentiation, 3t3l1 fibroblast and human hepatic stellate cell (hHSC) were cultured in dishes and 6-well plates with coverslips. In our previous research, mouse aortic smooth muscle cells (mASMC) seeded in 6-well plates grew in an osteogenic medium (10mM β-glycerophosphate and 10mM Calcium chloride) in the presence or absence of NE (10nM). Calcium deposits were detected by Alizarin staining. 3t3l1 and hHSC was treated with NE (20nM, 30nM, 40nM), BMP2, TGFβ1 or NE combined with BMP2, TGFβ1 or NE inhibitor GW311616A (Axon). Further, we used specific chemical inhibitors, LDN-193189, BMP-ALK2/3 inhibitor, SB525334, TGFβ-ALK5 inhibitor, and I-191, PAR2 antagonist to investigate the molecular mechanism of NE’s effects on Smad signaling pathways. Cells in dishes were harvested, and the proteins were measured by western blot. Coverslips in 6-well plates were used for immunofluorescence. RESULTS: The most severe calcification was found in the adipose tissue of HFHFD fed wild-type mice and moderate calcification took place in the HFD mouse group while NCD mice rarely had calcium deposits. NE-knockdown significantly prevented calcium deposits in adipose tissue compared with HFHFD wild-type mice. Consistently, we found increased phospho-Smad1/5 (p-Smad1/5) signaling in the adipose tissues of mice on the HFHFD and HFD mice while p-Smad1/5 was prevented in the NE-knockout group. Furthermore, NE enhanced calcium deposits in mASMC cultured in osteogenic medium. NE significantly activated p-Smad1/5 signaling in hHSC in the dose-effect relationship and contributes to an additive effect on p-Smad1/5 in the presence of BMP2 or TGFβ1. Although p-Smad1/5 was only slightly aroused by NE in 3t3l1 fibroblast, NE was able to promote p-Smad1/5 activation tremendously and specifically in the presence of BMP2 or TGFβ1 but not p-Smad2/3 which is the main downstream signaling of TGFβ1. Chemical inhibition of ALK2/3, not ALK5 or PAR2, was able to completely block NE’s effects in hSHC on p-Smad1/5 activation. In addition, the cleavage of osteoblast-cadherin or CDH11 (OB-cadherin) was observed in hHSC, which may indicate a lower beta-catenin abundance in the hHSC cells which were treated with NE. CONCLUSION: NE has the potential to contribute to abnormal calcification in soft tissues including the liver, adipose tissue and aorta via activating canonical ALK2/3-BMP-Smad1/5 signaling pathway in the mesenchymal stem cell/MSC-lineage cells. In addition, NE is likely to break cell-cell adhesion which may contribute to cell proliferation and re-differentiation towards osteogenesis and fibrosis. / 2024-01-28T00:00:00Z
224

In vivo imaging reveals PKA regulation of ERK activity during neutrophil recruitment to inflamed intestines / 炎症腸管へ浸潤する好中球内でのPKAおよびERK活性の生体内FRETイメージング

Mizuno, Rei 24 September 2014 (has links)
This dissertation is author version of following the journal article. Rei Mizuno, Yuji Kamioka, Kenji Kabashima, Masamichi Imajo, Kenta Sumiyama, Eiji Nakasho, Takeshi Ito, Yoko Hamazaki, Yoshihisa Okuchi, Yoshiharu Sakai, Etsuko Kiyokawa, and Michiyuki Matsuda. "In vivo imaging reveals PKA regulation of ERK activity during neutrophil recruitment to inflamed intestines" J Exp Med 2014 211:1123-1136. Published May 19, 2014, doi:10.1084/jem.20132112 / 京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18542号 / 医博第3935号 / 新制||医||1006(附属図書館) / 31442 / 京都大学大学院医学研究科医学専攻 / (主査)教授 岩井 一宏, 教授 千葉 勉, 教授 長澤 丘司 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
225

Serum Neutrophil Extracellular Trap Levels Predict Thrombotic Microangiopathy after Allogeneic Stem Cell Transplantation / 血清中の好中球細胞外トラップ増加は、同種造血幹細胞移植後の血栓性微小血管障害の発症を予測する

Arai, Yasuyuki 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18857号 / 医博第3968号 / 新制||医||1008(附属図書館) / 31808 / 京都大学大学院医学研究科医学専攻 / (主査)教授 前川 平, 教授 江藤 浩之, 教授 河本 宏 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
226

Obesity-promoting and anti-thermogenic effects of neutrophil gelatinase-associated lipocalin in mice / マウスにおけるneutrophil gelatinase-associated lipocalinの肥満促進および熱産生抑制効果

Ishii, Akira 26 March 2018 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(医学) / 乙第13168号 / 論医博第2155号 / 新制||医||1029(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 松田 道行, 教授 川口 義弥, 教授 近藤 玄 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
227

The Effect of Acute Exercise on Neutrophils and Oxidative Stress.

Quindry, John Carl 01 May 2002 (has links) (PDF)
This study tested the hypothesis that high intensity exercise, independent of total oxygen consumption, results in the most significant elevations in neutrophil (PMN) counts and blood oxidative stress (OS). This study also tested the hypothesis that active individuals have a blunted PMN and OS responses to acute exercise as compared to less active individuals. Nine males (18 – 30 yrs.) participated in 1 maximal (Max) and 3 sub-maximal exercise sessions. The 3 sub-max trials were: 1) LTplus, 45 min. above lactate threshold (LT), 2) LTminus, 45 min. below LT, and 3) LTplusCE, below LT until total oxygen consumption equaled (about 60 min) the LTplus trial. Blood was drawn before and immediately after, 1hr, and 2hr after exercise for measurement of PMN, myeloperoxidase enzyme (MPO), superoxide (O2-), vitamin C (C), urate (U), malondialdehyde (MDA), and lipid hydroperoxides (LPO). Results indicated an intensity-dependent post exercise PMN increase following Max and LTplus (p≤0.05). Post exercise MPO elevations were significant (p≤0.05) and similar for all trials except LTplus (NS). Furthermore, O2- was elevated immediately following Max exercise, while O2-/PMN was not. These data indicate that O2- elevations occur as PMN counts increase. Post-max, C (p=0.009), and U (p=0.034) were depleted indicating a significant reduction in plasma antioxidant fortifications. Subjects were separated according to high (n=5) and low (n=4) activity groups based on physical activity history questionnaires. Low activity subjects had higher PMN following maximal exercise. Pre exercise Low – High group differences neared significance for PMN (p=0.068) and O2- (p=0.09). High activity subjects had higher plasma C levels before and after exercise. Covariate analysis of dietary C intake demonstrated between group differences in plasma vitamin C levels at rest only. These results indicate that maximal intensity exercise resulted in the greatest increase in circulating PMNs and corresponding OS in blood plasma as identified by antioxidant depletion. This study clearly shows that exercise intensity, not total oxygen consumption, plays a role in post exercise neutrophil recruitment, and blood OS. Finally, these results suggest that regular physical activity and increased antioxidant intakes may attenuate the neutrophil rise and OS produced by maximal intensity exercise.
228

Biophysical Parameters of Nucleic Acid Binding Proteins and Protein-Protein Interactions

Refaei, Mary Anne January 2022 (has links)
No description available.
229

Interleukin-8 as a genetic modifier and pharmacologic target for cystic fibrosis pulmonary disease

Hillian, Antoinette D. 01 August 2009 (has links)
No description available.
230

Acute Phase T Cell Help in Neutrophil-Mediated Clearance of Helicobacter pylori

DeLyria, Elizabeth S. 23 January 2010 (has links)
No description available.

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