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951.
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Garzon-Muvdi T Schiapparelli P ap Rhys C Guerrero-Cazares H Smith C Kim DH Kone L Farber H Lee DY An SS Levchenko A Quiñones-Hinojosa A 《PLoS biology》2012,10(5):e1001320
Glioblastoma (GB) is a highly invasive and lethal brain tumor due to its universal recurrence. Although it has been suggested that the electroneutral Na(+)-K(+)-Cl(-) cotransporter 1 (NKCC1) can play a role in glioma cell migration, the precise mechanism by which this ion transporter contributes to GB aggressiveness remains poorly understood. Here, we focused on the role of NKCC1 in the invasion of human primary glioma cells in vitro and in vivo. NKCC1 expression levels were significantly higher in GB and anaplastic astrocytoma tissues than in grade II glioma and normal cortex. Pharmacological inhibition and shRNA-mediated knockdown of NKCC1 expression led to decreased cell migration and invasion in vitro and in vivo. Surprisingly, knockdown of NKCC1 in glioma cells resulted in the formation of significantly larger focal adhesions and cell traction forces that were approximately 40% lower than control cells. Epidermal growth factor (EGF), which promotes migration of glioma cells, increased the phosphorylation of NKCC1 through a PI3K-dependant mechanism. This finding is potentially related to WNK kinases. Taken together, our findings suggest that NKCC1 modulates migration of glioma cells by two distinct mechanisms: (1) through the regulation of focal adhesion dynamics and cell contractility and (2) through regulation of cell volume through ion transport. Due to the ubiquitous expression of NKCC1 in mammalian tissues, its regulation by WNK kinases may serve as new therapeutic targets for GB aggressiveness and can be exploited by other highly invasive neoplasms. 相似文献
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Röhrich CR Ngwa CJ Wiesner J Schmidtberg H Degenkolb T Kollewe C Fischer R Pradel G Vilcinskas A 《Biology letters》2012,8(2):308-311
The harlequin ladybird beetle Harmonia axyridis has been introduced in many countries as a biological control agent, but has become an invasive species threatening the biodiversity of native ladybirds. Its invasive success has been attributed to its vigorous resistance against diverse pathogens. This study demonstrates that harmonine ((17R,9Z)-1,17-diaminooctadec-9-ene), which is present in H. axyridis haemolymph, displays broad-spectrum antimicrobial activity that includes human pathogens. Antibacterial activity is most pronounced against fast-growing mycobacteria and Mycobacterium tuberculosis, and the growth of both chloroquine-sensitive and -resistant Plasmodium falciparum strains is inhibited. Harmonine displays gametocytocidal activity, and inhibits the exflagellation of microgametocytes and zygote formation. In an Anopheles stephensi mosquito feeding model, harmonine displays transmission-blocking activity. 相似文献
956.
Optogenetic approaches allow the manipulation of neuronal activity patterns in space and time by light, particularly in small animals such as zebrafish. However, most techniques cannot control neuronal activity independently at different locations. Here we describe equipment and provide a protocol for single-photon patterned optical stimulation of neurons using a digital micromirror device (DMD). This method can create arbitrary spatiotemporal light patterns with spatial and temporal resolutions in the micrometer and submillisecond range, respectively. Different options to integrate a DMD into a multiphoton microscope are presented and compared. We also describe an ex vivo preparation of the adult zebrafish head that greatly facilitates optogenetic and other experiments. After assembly, the initial alignment takes about one day and the zebrafish preparation takes <30 min. The method has previously been used to activate channelrhodopsin-2 and manipulate oscillatory synchrony among spatially distributed neurons in the zebrafish olfactory bulb. It can be adapted easily to a wide range of other species, optogenetic probes and scientific applications. 相似文献
957.
Malmberg EK Pelaseyed T Petersson AC Seidler UE De Jonge H Riordan JR Hansson GC 《The Biochemical journal》2008,410(2):283-289
The membrane-bound mucins have a heavily O-glycosylated extracellular domain, a single-pass membrane domain and a short cytoplasmic tail. Three of the membrane-bound mucins,MUC3, MUC12 and MUC17, are clustered on chromosome 7 and found in the gastrointestinal tract. These mucins have C-terminal sequences typical of PDZ-domain-binding proteins. To identify PDZ proteins that are able to interact with the mucins,we screened PDZ domain arrays using YFP (yellow fluorescent protein)-tagged proteins. MUC17 exhibited a strong binding to PDZK1 (PDZ domain containing 1), whereas the binding toNHERF1 (Na+/H+-exchanger regulatory factor 1) was weak.Furthermore, we showed weak binding of MUC12 to PDZK1, NHERF1 and NHERF2. GST (glutathione transferase) pull-down experiments confirmed that the C-terminal tail of MUC17 coprecipitates with the scaffold protein PDZK1 as identified byMS. This was mediated through the C-terminal PDZ-interaction site in MUC17, which was capable of binding to three of the four PDZ domains in PDZK1. Immunostaining of wild-type or Pdzk1-/- mouse jejunum with an antiserum against Muc3(17),the mouse orthologue of human MUC17, revealed strong brushborder membrane staining in the wild-type mice compared with an intracellular Muc3(17) staining in the Pdzk1-/- mice. This suggests that Pdzk1 plays a specific role in stabilizing Muc3(17)in the apical membrane of small intestinal enterocytes. 相似文献
958.
Biomarker candidates for cardiovascular disease and bone metabolism disorders in chronic kidney disease: a systems biology perspective 总被引:1,自引:0,他引:1
959.
Twenty-eight [6-(aminomethyl)nicotinate]dichloridoplatinum(II) complexes 1 esterified with various terpene alcohols either directly or via alkyl spacers were tested for antiproliferative activity in human 518A2 melanoma and HL-60 leukemia cells. Generally, conjugates with menthanes and polycyclic sesquiterpenes attached via propane-1,2-diyl spacers were most active. In the melanoma cells, the propane-1,2-diyl-spacered conjugates of (-)-menthol (1a(2')), (+)-neomenthol (1b(2')), (-)-carvomenthol (1h(2')), and (-)-isolongifolol (1n(2')) displayed growth inhibition at IC(50)<4 microM which is ten times smaller than that of cisplatin. The stationary diamino ligand was also crucial. The (-)-menthyl ester complexes with 2,3-diaminopropanoate (9a) and 2,4-diaminobutanoate (10a) ligands caused a greater and persistent growth inhibition in HT-29 colon cancer cells upon long-term exposure when compared to the 6-(aminomethyl)nicotinate analogue 1a. The cedrenyl ester 1l and the menthoxyisopropyl ester 1a(2') proved most efficacious in all three tumor cell lines. The DNA binding of complexes 1 was assessed by electrophoretic band-shift experiments and found correlated to the terpene structure but not to the observed antiproliferative activities. 相似文献
960.
Education shows that active participation allows the best development of skills to acquire, and the results are better when the information is well documented. Now, with digital images and the Internet, in the case of the Static Telepathology (ST), it is easy to share macroscopic and microscopic photographs. The progress of the technologies enabled a form of Dynamic Telepathology (DT) named "virtual slides", with navigation tools, and can be moved around changing powers as desired, making any personal computer into a digital microscope. The use of these tools in continuous education leads to optimal development of knowledge. We reported the experience of a Latin-American Pathologist from La Rioja, a small Province of Argentina, and we also mentioned the electronic publications in Virtual Hispano-American Congresses of Pathology (VHACP) since 1997(18 reports in the case of ST) and in two Virtual Slide Congress (VSC). In the 1st (2005) and 2nd (2007) Internet VSCs two of our cases were digitized in Spain (case 1 and 3 respectively). In these Virtual Slides, the microscopic images can be moved remotely from any computer connected to the Internet, we should recognize that it will become a valuable continuing Medical Education tool in microscopy, probably related to the phrase "a picture is worth more than a thousand words", then we might add; "what about thousands of images?" Similarly, the autoevaluation test is very important. ST and DT, in support of Virtual Congresses allows learning, teaching and sharing of diseases in scientific presentations and the exchange of views in the forums, these are the optimum material for distance education. In addition we received CDs or DVDs and certificates as authors, recognized by European Institutions. The active participation and the autoevaluation test are the best tools for continuous medical education in telepathology, not only for pathologists in developing countries but for the entire world. 相似文献