Journal of biophysics (Hindawi Publishing Corporation : Online)最新文献_第5页

Role of the endothelium during tumor cell metastasis: is the endothelium a barrier or a promoter for cell invasion and metastasis? 内皮在肿瘤细胞转移中的作用:内皮是细胞侵袭和转移的屏障还是促进因子?

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2009-03-05 DOI: 10.1155/2008/183516

Claudia Tanja Mierke

{"title":"Role of the endothelium during tumor cell metastasis: is the endothelium a barrier or a promoter for cell invasion and metastasis?","authors":"Claudia Tanja Mierke","doi":"10.1155/2008/183516","DOIUrl":"https://doi.org/10.1155/2008/183516","url":null,"abstract":"The malignancy of cancer disease depends on the ability of the primary tumor to metastasize to distant organs. The process of the metastasis formation has largely been analyzed, but still main pathways regarding the extravasation step at the end of the metastasis formation process are controversially discussed. An agreement has been reached about the importance of the endothelium to promote metastasis formation either by enhancing the growth of the primary tumor or by homing (targeting) the tumor cells to blood or lymph vessels. The mechanical properties of the invading tumor cells become the focus of several studies, but the endothelial cell mechanical properties are still elusive. This paper describes the different roles of the endothelium in the process of metastasis formation and focuses on a novel role of the endothelium in promoting tumor cell invasion. It discusses how novel biophysical tools and in vivo animal models help to determine the role of the endothelium in the process of tumor cell invasion. Evidence is provided that cell mechanical properties, for example, contractile force generation of tumor cells, are involved in the process of tumor cell invasion.","PeriodicalId":73623,"journal":{"name":"Journal of biophysics (Hindawi Publishing Corporation : Online)","volume":"2008 ","pages":"183516"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2008/183516","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28674682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 70

Selective detection of NADPH oxidase in polymorphonuclear cells by means of NAD(P)H-based fluorescence lifetime imaging. 基于NAD(P) h荧光寿命成像的多形核细胞NADPH氧化酶选择性检测。

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2008-11-16 DOI: 10.1155/2008/602639

R Niesner, P Narang, H Spiecker, V Andresen, K-H Gericke, M Gunzer

{"title":"Selective detection of NADPH oxidase in polymorphonuclear cells by means of NAD(P)H-based fluorescence lifetime imaging.","authors":"R Niesner, P Narang, H Spiecker, V Andresen, K-H Gericke, M Gunzer","doi":"10.1155/2008/602639","DOIUrl":"https://doi.org/10.1155/2008/602639","url":null,"abstract":"NADPH oxidase (NOX2) is a multisubunit membrane-bound enzyme complex that, upon assembly in activated cells, catalyses the reduction of free oxygen to its superoxide anion, which further leads to reactive oxygen species (ROS) that are toxic to invading pathogens, for example, the fungus Aspergillus fumigatus. Polymorphonuclear cells (PMNs) employ both nonoxidative and oxidative mechanisms to clear this fungus from the lung. The oxidative mechanisms mainly depend on the proper assembly and function of NOX2. We identified for the first time the NAD(P)H-dependent enzymes involved in such oxidative mechanisms by means of biexponential NAD(P)H-fluorescence lifetime imaging (FLIM). A specific fluorescence lifetime of 3670 +/- 140 picoseconds as compared to 1870 picoseconds for NAD(P)H bound to mitochondrial enzymes could be associated with NADPH bound to oxidative enzymes in activated PMNs. Due to its predominance in PMNs and due to the use of selective activators and inhibitors, we strongly believe that this specific lifetime mainly originates from NOX2. Our experiments also revealed the high site specificity of the NOX2 assembly and, thus, of the ROS production as well as the dynamic nature of these phenomena. On the example of NADPH oxidase, we demonstrate the potential of NAD(P)H-based FLIM in selectively investigating enzymes during their cellular function.","PeriodicalId":73623,"journal":{"name":"Journal of biophysics (Hindawi Publishing Corporation : Online)","volume":"2008 ","pages":"602639"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2008/602639","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28674601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 33

Roots of diversity relations. 多样性关系的根源。

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2008-12-11 DOI: 10.1155/2008/654672

Peter Würtz, Arto Annila

引用次数: 32

Molecular processes in biological thermosensation. 生物热感觉的分子过程。

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2008-05-12 DOI: 10.1155/2008/602870

I Digel, P Kayser, G M Artmann

引用次数: 22

Cell volume and sodium content in rat kidney collecting duct principal cells during hypotonic shock. 低渗休克时大鼠肾集管主细胞的细胞体积和钠含量。

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2008-07-27 DOI: 10.1155/2008/420963

Evgeny I Solenov

{"title":"Cell volume and sodium content in rat kidney collecting duct principal cells during hypotonic shock.","authors":"Evgeny I Solenov","doi":"10.1155/2008/420963","DOIUrl":"https://doi.org/10.1155/2008/420963","url":null,"abstract":"The purpose of this study was to investigate the time course of the volume-regulatory response and intracellular sodium concentration ([Na(+)](i)) in the principal cells of rat kidney outer medulla collecting duct (OMCD) epithelia during acute swelling in hypotonic medium. Hypotonic shock was created by PBS diluted with 50% of water. Changes in cell volume were measured with calcein quenching method. Intracellular sodium concentration was studied with fluorescence dye Sodium Green. Principal cells of microdissected OMCD fragments swelled very fast. The characteristic time of swelling (tau(1)) was 0.65 +/- 0.05 seconds, and the volume increased more than 60% (92.9 +/- 5.6 and 151.3 +/- 9.8 microm(3) control and peak volumes correspondently, P < .01). After cell volume reached the peak of swelling, the RVD began without lag period. The characteristic time of volume decreasing to new steady-state level (tau(2)) was 8.9 +/- 1.1 seconds. In hypoosmotic medium, cell volume stabilized on higher level in comparison with control (110.3 +/- 8.3 microm(3), P < .01). After restoration of the medium osmolality to normotonic, cell volume stabilized on significantly low level in comparison with control level (71.4 +/- 6.1 microm(3), P < .01). During the hypoosmotic shock, [Na(+)](i) decreased from control level in isotonic PBS to the low level in hypoosmotic solution (27.7 +/- 1.4 and 5.8 +/- 0.23 mM, P < .01). Calculation of sodium content per cell has shown the significant sodium entry into the cells, which caused a temporary increase correlated with the peak of cell volume caused by swelling. The conclusion is made that in our model of hypoosmotic shock, swelling activates transporters with high permeability for Na(+) that provides sodium flux into the cells.","PeriodicalId":73623,"journal":{"name":"Journal of biophysics (Hindawi Publishing Corporation : Online)","volume":"2008 ","pages":"420963"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2008/420963","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28674599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Flexibility of the cytoplasmic domain of the phototaxis transducer II from Natronomonas pharaonis. 法老钠单胞菌趋光性换能器II细胞质结构域的柔韧性。

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2008-10-16 DOI: 10.1155/2008/267912

Ivan L Budyak, Olga S Mironova, Naveena Yanamala, Vijayalaxmi Manoharan, Georg Büldt, Ramona Schlesinger, Judith Klein-Seetharaman

{"title":"Flexibility of the cytoplasmic domain of the phototaxis transducer II from Natronomonas pharaonis.","authors":"Ivan L Budyak, Olga S Mironova, Naveena Yanamala, Vijayalaxmi Manoharan, Georg Büldt, Ramona Schlesinger, Judith Klein-Seetharaman","doi":"10.1155/2008/267912","DOIUrl":"https://doi.org/10.1155/2008/267912","url":null,"abstract":"Chemo- and phototaxis systems in bacteria and archaea serve as models for more complex signal transduction mechanisms in higher eukaryotes. Previous studies of the cytoplasmic fragment of the phototaxis transducer (pHtrII-cyt) from the halophilic archaeon Natronomonas pharaonis showed that it takes the shape of a monomeric or dimeric rod under low or high salt conditions, respectively. CD spectra revealed only approximately 24% helical structure, even in 4 M KCl, leaving it an open question how the rod-like shape is achieved. Here, we conducted CD, FTIR, and NMR spectroscopic studies under different conditions to address this question. We provide evidence that pHtrII-cyt is highly dynamic with strong helical propensity, which allows it to change from monomeric to dimeric helical coiled-coil states without undergoing dramatic shape changes. A statistical analysis of predicted disorder for homologous sequences suggests that structural flexibility is evolutionarily conserved within the methyl-accepting chemotaxis protein family.","PeriodicalId":73623,"journal":{"name":"Journal of biophysics (Hindawi Publishing Corporation : Online)","volume":"2008 ","pages":"267912"},"PeriodicalIF":0.0,"publicationDate":"2008-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2008/267912","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28674683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Antidepressant interactions with the NMDA NR1-1b subunit. 抗抑郁药与NMDA NR1-1b亚基的相互作用。

Journal of biophysics (Hindawi Publishing Corporation : Online) Pub Date : 2008-01-01 Epub Date: 2008-06-05 DOI: 10.1155/2008/474205

Richard Raabe, Lisa Gentile

引用次数: 10