208 research outputs found

    Combined High-Speed Single Particle Tracking of Membrane Proteins and Super-resolution of Membrane-Associated Structures

    Get PDF
    Many experiments have shown that the diffusive motion of lipids and membrane proteins are slower on the cell surface than those in artificial lipid bilayers or blebs. One hypothesis that may partially explain this mystery is the effect of the cytoskeleton structures on the protein dynamics. A model proposed by Kusumi [1] is the Fence-Picket Model which describes the cell membrane as a set of compartment regions, each ~ 10 to 200 nm in size, created by direct or indirect interaction of lipids and proteins with actin filaments just below the membrane. To test this hypothesis, we have assembled a high-speed single particle tracking microscope and use a hybrid tracking and super-resolution approach on the same cell. We labeled the high-affinity FceRI receptor in Rat Basophilic Leukemia (RBL) cells and tracked these transmembrane proteins at up to 1000 frames per second. The cells were fixed immediately after tracking and further labeled for super-resolution imaging of actin filaments and other membrane-associated components were collected. For best correlation of tracking and super-resolution, we refined a fixation protocol to prevent morphology changes during the fixation process that often go unnoticed. Bright field images allow re-alignment of cell with about ~ 10 nm precision. This sequential approach allows use of far-red dyes for tracking and super-resolution, ameliorating chromatic aberrations. We will present the results of this high-speed tracking within the context of actin and other membrane associated proteins imaged with ~ 20 nm resolution. [1].Ritchie, K.; Iino, R.; Fujiwara, T.; Murase, K.; Kusumi, A. The fence and picket structure of the plasma membrane of live cells as revealed by single molecule techniques (Review). Mol. Membr. Biol. 2003, 20, 13−18

    Targeting Btk/Etk of prostate cancer cells by a novel dual inhibitor.

    Get PDF
    Btk and Etk/BMX are Tec-family non-receptor tyrosine kinases. Btk has previously been reported to be expressed primarily in B cells and has an important role in immune responses and B-cell malignancies. Etk has been shown previously to provide a strong survival and metastasis signal in human prostate cancer cells, and to confer androgen independence and drug resistance. While the role of Etk in prostate carcinogenesis is well established, the functions of Btk in prostate cancer have never been investigated, likely due to the perception that Btk is a hematopoietic, but not epithelial, kinase. Herein, we found that Btk is overexpressed in prostate cancer tissues and prostate cancer cells. The level of Btk in prostate cancer tissues correlates with cancer grades. Knockdown of Btk expression selectively inhibits the growth of prostate cancer cells, but not that of the normal prostate epithelial cells, which express very little Btk. Dual inhibition of Btk and Etk has an additive inhibitory effect on prostate cancer cell growth. To explore Btk and Etk as targets for prostate cancer, we developed a small molecule dual inhibitor of Btk and Etk, CTN06. Treatment of PC3 and other prostate cancer cells, but not immortalized prostate epithelial cells with CTN06 resulted in effective cell killing, accompanied by the attenuation of Btk/Etk signals. The killing effect of CTN06 is more potent than that of commonly used inhibitors against Src, Raf/VEGFR and EGFR. CTN06 induces apoptosis as well as autophagy in human prostate cancer cells, and is a chemo-sensitizer for docetaxel (DTX), a standard of care for metastatic prostate cancer patients. CTN06 also impeded the migration of human prostate cancer cells based on a 'wound healing' assay. The anti-cancer effect of CTN06 was further validated in vivo in a PC3 xenograft mouse model

    Hepatitis E Virus Seroprevalence Among Blood Donors in Bushehr, South of Iran.

    Get PDF
    BACKGROUND: Although so far several studies have determined the hepatitis E virus (HEV) prevalence in some parts of Iran, no data exists regarding the HEV seroprevalence in Bushehr province as the southernmost point in Iran yet. OBJECTIVES: The aim of this study was to evaluate the seroprevalence of anti-HEV IgG among the blood donors in Bushehr. PATIENTS AND METHODS: A total of 628 blood donor samples were collected from September to October 2013, after obtaining informed written consents, and analyzed for the presence of anti-HEV IgG using commercial HEV enzyme-linked immunosorbent assay (ELISA) kit. All the samples were tested by two ELISA kits and evaluated for liver function test. RESULTS: Overall, 105 (16.7%) blood samples were positive for HEV-specific-IgG antibodies, while 523 (83.8%) were negative. The presence of anti-HEV IgG was not associated with gender; however, it was correlated with age. It was indicated that the anti-HEV prevalence increases by age and there was a significant difference between the age groups regarding HEV seropositivity. CONCLUSIONS: High HEV seroprevalence (16.7%) was observed among the blood donors in Bushehr province. It appears that exposure to HEV increases with age; although, more people should be examined

    ANTIBACTERIAL & ANTIFUNGAL POTENTIALITY OF RICINUS COMMUNIS & COLEUS FORSKOHLII ON SOME HUMAN PATHOGENIC MICROORGANISMS

    Get PDF
    The objective of the present study was to explore the antibacterial and antifungal activity of two plant extracts (Ricinus communis & Coleus forskohlii) against some selected pathogen (Staphylococcus aureus

    Effect of foliar application of salicylic acid and mycorrhiza on quantitative and qualitative traits of maize

    Get PDF
    Abstract An experiment was performed to investigate the effect of mycorrhizal symbiosis and foliar application of salicylic acid on quantitative and qualitative traits of maize during 2018 and 2019 in the research farm of Islamic Azad University, Chalous Branch. Split plot in a randomized complete block design with three replications was used. Experimental factors included mycorrhiza species of (G. mosseae), (G. geosporum) and (G. intraradices) at two levels (no consumption and consumption of mycorrhiza) and salicylic acid at two levels (no consumption and consumption of 1 mμ of salicylic acid). Results of interaction effects of mycorrhiza and salicylic acid on the measured traits revealed that the maximum 1000-grain weight, grain yield, biological yield, phosphorus, potassium, nitrogen percentage and yield of maize grain protein were observed in G. mosseae treatment under foliar application of salicylic acid. Foliar application of salicylic acid increases the root length and provides the necessary conditions for increasing water and nutrient uptake alongwith increase in photosynthesis and thus allocates more photosynthetic substance for development of reproductive organs. Hence, it increases maize grain weight and accordingly grain yield. In general, the results revealed that mycorrhiza and foliar application of salicylic acid increase growth indicators, yield and yield components. It also improved the quality traits of the maize plant. Based on results, the interaction effect of G. mosseae treatment and foliar application of salicylic acid yielded better results than other treatments. Mycorrhiza increases the number of grain in the ear, the number of rows in the ear, increases the plant's ability to absorb phosphorus, and the increase of mycorrhiza along with salicylic acid shows the maximum grain yield in maize. Finally, it can be concluded that the use of mycorrhiza and salicylic acid can be effective in increasing grain in the plant

    The effects of lifestyle modifications including dietary and physical interventions with cognitive-behavioral therapy on quality of life and cancer-recurrence rate among patients with breast cancer and survivors: A protocol for a systematic review and meta-analysis of randomized controlled trial

    Get PDF
    Context: Lifestyle modifications consist of three components including diet, exercise, and cognitive-behavioral therapy which can reduce side effects of breast cancer. Cognitive-behavioral therapy is a complementary strategy that promotes new skills for any treatment. Published trials have investigated the co-efficacies of the two or three components of lifestyle modifications, especially dietary and cognitive-behavioral interventions in breast cancer survivors. Evidence Acquisition: This protocol is about a meta-analysis which will systematically report the simultaneous effects of dietary intervention or physical activity with cognitive-behavioral therapy, or three of them on quality of life, the recurrence levels and anthropometric measurements among patients with breast cancer and survivors. It was prepared in accordance with the PRISMAP checklist and will be performed in accordance with the Cochrane Handbook for Systematic reviews of intervention. Cochrane Central Register of Controlled trials, PubMed, EMBASE and ISI web of science will be searched for peer-reviewed literature using defined MeSH terms. Included randomized controlled trials on the combination effects of cognitive-behavioral therapy with either dietary or physical interventions will be assessed. Continuous data will be meta-analyzed using the STATA and will be gathered using random-effects models. The effect size will be reported as standardized mean difference with 95CIs. Heterogeneity assessment, publication bias, and sensitivity analysis will be performed. The heterogeneity between some trials may be a limitation of this study. Conclusions: This meta-analysis will provide beneficial guidance for healthcare providers and family members to improve the current understanding of the role of lifestyle modification on alleviating the important problems of patients with breast cancer. © 2020, Author(s)

    Bayesian Multiple Emitter Fitting using Reversible Jump Markov Chain Monte Carlo

    Get PDF
    In single molecule localization-based super-resolution imaging, high labeling density or the desire for greater data collection speed can lead to clusters of overlapping emitter images in the raw super-resolution image data. We describe a Bayesian inference approach to multiple-emitter fitting that uses Reversible Jump Markov Chain Monte Carlo to identify and localize the emitters in dense regions of data. This formalism can take advantage of any prior information, such as emitter intensity and density. The output is both a posterior probability distribution of emitter locations that includes uncertainty in the number of emitters and the background structure, and a set of coordinates and uncertainties from the most probable model

    Entanglement of trapped-ion qubits separated by 230 meters

    Full text link
    We report on an elementary quantum network of two atomic ions separated by 230 m. The ions are trapped in different buildings and connected with 520(2) m of optical fiber. At each network node, the electronic state of an ion is entangled with the polarization state of a single cavity photon; subsequent to interference of the photons at a beamsplitter, photon detection heralds entanglement between the two ions. Fidelities of up to (88.2+2.36.0)%(88.2+2.3-6.0)\% are achieved with respect to a maximally entangled Bell state, with a success probability of 4×1054 \times 10^{-5}. We analyze the routes to improve these metrics, paving the way for long-distance networks of entangled quantum processors

    Comparing lifeact and phalloidin for super-resolution imaging of actin in fixed cells

    Get PDF
    Visualizing actin filaments in fixed cells is of great interest for a variety of topics in cell biology such as cell division, cell movement, and cell signaling. We investigated the possibility of replacing phalloidin, the standard reagent for super-resolution imaging of F-actin in fixed cells, with the actin binding peptide 'lifeact'. We compared the labels for use in single molecule based super-resolution microscopy, where AlexaFluor 647 labeled phalloidin was used in a dSTORM modality and Atto 655 labeled lifeact was used in a single molecule imaging, reversible binding modality. We found that imaging with lifeact had a comparable resolution in reconstructed images and provided several advantages over phalloidin including lower costs, the ability to image multiple regions of interest on a coverslip without degradation, simplified sequential super-resolution imaging, and more continuous labeling of thin filaments
    corecore