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991.
992.
XPO1 Inhibition Preferentially Disrupts the 3D Nuclear Organization of Telomeres in Tumor Cells 下载免费PDF全文
Cheryl Taylor‐Kashton Daniel Lichtensztejn Erkan Baloglu William Senapedis Sharon Shacham Michael G. Kauffman Rami Kotb Sabine Mai 《Journal of cellular physiology》2016,231(12):2711-2719
Previous work has shown that the three‐dimensional (3D) nuclear organization of telomeres is altered in cancer cells and the degree of alterations coincides with aggressiveness of disease. Nuclear pores are essential for spatial genome organization and gene regulation and XPO1 (exportin 1/CRM1) is the key nuclear export protein. The Selective Inhibitor of Nuclear Export (SINE) compounds developed by Karyopharm Therapeutics (KPT‐185, KPT‐330/selinexor, and KPT‐8602) inhibit XPO1 nuclear export function. In this study, we investigated whether XPO1 inhibition has downstream effects on the 3D nuclear organization of the genome. This was assessed by measuring the 3D telomeric architecture of normal and tumor cells in vitro and ex vivo. Our data demonstrate for the first time a rapid and preferential disruption of the 3D nuclear organization of telomeres in tumor cell lines and in primary cells ex vivo derived from treatment‐naïve newly diagnosed multiple myeloma patients. Normal primary cells in culture as well as healthy lymphocyte control cells from the same patients were minimally affected. Using both lymphoid and non‐lymphoid tumor cell lines, we found that the downstream effects on the 3D nuclear telomere structure are independent of tumor type. We conclude that the 3D nuclear organization of telomeres is a sensitive indicator of cellular response when treated with XPO1 inhibitors. J. Cell. Physiol. 231: 2711–2719, 2016. © 2016 The Authors. Journal of Cellular Physiology published by Wiley Periodicals, Inc. 相似文献
993.
Zoë W. Thorbergson Sharon G. Nielsen Rodney J. Beaulieu Rebecca E. Doyle 《Journal of applied animal welfare science : JAAWS》2016,19(3):245-259
Riding is considered to be an arousing activity for horses. It has been suggested that wither scratching may be a more useful tool for relaxation compared with the common practice of neck patting. In the current study, 18 horses were exposed to 3 treatments, including control or no interaction, neck patting, and wither scratching, for 1 min each following a short obstacle course. Heart rate, heart rate variability, and a variety of behaviors were measured in the horses. Wither scratching produced a significantly longer duration of relaxed-type behaviors. Wither scratching could be a useful tool to help a horse relax while under saddle. Additionally, the study identified 2 ear positions that may be useful for future research in horse behavior. 相似文献
994.
995.
Moa Rehn Ingrid Uhnoo Sharon Kühlmann-Berenzon Anders Wallensten P?r Sparén Eva Netterlid 《PloS one》2016,11(3)
Background
The Swedish school-based vaccination programme offers HPV vaccine to girls born ≥1999 in 5-6th grade. In 2012, all counties introduced free-of-charge catch-up vaccination campaigns targeting girls born 1993–1998. Varying vaccine uptake in the catch-up group by December 2012 suggested that some implementation strategies were more successful than others. In order to inform future vaccination campaigns, we assessed the impact of different implementation strategies on the county-level catch-up vaccine uptake.Methods
We conducted an ecological study including all Swedish counties (n = 21), asking regional health offices about the information channels they used and where vaccination of the catch-up target group took place in their counties. The uptake of ≥1 dose by 30 September 2014 was estimated using data from the voluntary national vaccination register. We investigated associations between counties’ catch-up vaccine uptake, information channels and vaccination settings by calculating incidence rate ratios (IRR) and 95% confidence intervals (CI), using negative binomial regression models.Results
County level catch-up vaccine uptake varied between 49–84%. All counties offered vaccination through primary health care settings. Apart from this eight (34%) also offered the vaccine in some of their schools, four (19%) in all their schools, and two (10%) in other health care centres. The information channels most frequently used were: information at the national on-line health care consulting web-page (100%), letter/invitations (90%), and advertisement (81%). Counties offering vaccination to girls in all schools and counties offering vaccination in some of their schools, reached higher vaccine uptake compared to counties not offering vaccination in any of their schools (all schools adjusted IRR: 1.3, 95% CI: 1.1–1.5, some schools adjusted IRR: 1.2, 95% CI: 1.1–1.3).Conclusion
Counties offering HPV vaccination to catch-up groups in schools reached the highest vaccine uptake. No information channel explained differences in county-level vaccine uptake. Our findings suggest that catch-up vaccination outside the national vaccination program can reach a high uptake at the population level if it is implemented primarily with an organized delivery (e.g. in schools). 相似文献996.
Lisa M. Puchalski Ritchie Monique van Lettow Austine Makwakwa Adrienne K. Chan Jemila S. Hamid Harry Kawonga Alexandra L. C. Martiniuk Michael J. Schull Vanessa van Schoor Merrick Zwarenstein Jan Barnsley Sharon E. Straus 《Trials》2016,17(1)
BackgroundDespite availability of effective treatment, tuberculosis (TB) remains an important cause of morbidity and mortality globally, with low- and middle-income countries most affected. In many such settings, including Malawi, the high burden of disease and severe shortage of skilled healthcare workers has led to task-shifting of outpatient TB care to lay health workers (LHWs). LHWs improve access to healthcare and some outcomes, including TB completion rates, but lack of training and supervision limit their impact. The goals of this study are to improve TB care provided by LHWs in Malawi by refining, implementing, and evaluating a knowledge translation strategy designed to address a recognized gap in LHWs’ TB and job-specific knowledge and, through this, to improve patient outcomes.Methods/designWe are employing a mixed-methods design that includes a pragmatic cluster randomized controlled trial and a process evaluation using qualitative methods. Trial participants will include all health centers providing TB care in four districts in the South East Zone of Malawi. The intervention employs educational outreach, a point-of-care reminder tool, and a peer support network. The primary outcome is proportion of treatment successes, defined as the total of TB patients cured or completing treatment, with outcomes taken from Ministry of Health treatment records. With an alpha of 0.05, power of 0.80, a baseline treatment success of 0.80, intraclass correlation coefficient of 0.1 based on our pilot study, and an estimated 100 clusters (health centers providing TB care), a minimum of 6 patients per cluster is required to detect a clinically significant 0.10 increase in the proportion of treatment successes. Our process evaluation will include interviews with LHWs and patients, and a document analysis of LHW training logs, quarterly peer trainer meetings, and mentorship meeting notes. An estimated 10–15 LHWs and 10–15 patients will be required to reach saturation in each of 2 planned interview periods, for a total of 40–60 interview participants.DiscussionThis study will directly inform the efforts of knowledge users within TB care and, through extension of the approach, other areas of care provided by LHWs in Malawi and other low- and middle-income countries.
Trial registration
ClinicalTrials.gov . Registered 20 August 2015. Protocol Date/Version 29 May 2016/Version 2. NCT02533089Electronic supplementary material
The online version of this article (doi:10.1186/s13063-016-1563-2) contains supplementary material, which is available to authorized users. 相似文献997.
Donald P. Braun Sharon Nisius Ariel Hollinshead Jules E. Harris 《Cancer immunology, immunotherapy : CII》1983,15(2):114-120
Summary Immunoregulation of phytohemagglutinin (PHA) responsiveness by glass-adherent cells and prostaglandin-synthesizing cells was serially monitored in the peripheral blood mononuclear cells (PBMC) of surgically resected stage I and stage II lung cancer patients entered on a trial of adjuvant immunotherapy. The relationship between immunoregulatory cell function, immunocompetence, and disease relapse was determined. Immunoregulatory activity was measured in PHA-stimulated cultures in the presence and absence of 2 g/ml indomethacin and in the presence and absence of glass-adherent cells. In each instance of disease relapse seen, an increase in immunoregulatory cell function to a level significantly different from normal was observed 3 months prior to or coincident with clinical confirmation of disease recurrence. This was usually associated with a decline in PHA responsiveness. In the patients who did not relapse, the levels of PHA responsiveness and immunoregulatory function persisted within normal limits throughout the course of study. Percentages and numbers of leukocytes and leukocyte subsets and delayed cutaneous hypersensitivity were also monitored in this study, but could not be consistently correlated with early changes in clinical disease status. These data suggest that the development of indomethacin-sensitive and glass-adherent suppressor cells may precede and predict for tumor recurrence in surgically resected lung cancer patients. 相似文献
998.
Peanut agglutinin, a new mitogen that binds to galactosyl sites exposed after neuraminidase treatment. 总被引:12,自引:0,他引:12
A Novogrodsky R Lotan A Ravid N Sharon 《Journal of immunology (Baltimore, Md. : 1950)》1975,115(5):1243-1248
Peanut agglutinin, purified by affinity chromatography, agglutinates lymphocytes from mouse, rat, guinea pig, and man only after their treatment with neuraminidase. However, it stimulates only neuraminidase-treated rat and human cells. A similar number cell surface receptors for peanut agglutinin was found on neuraminidase-treated rat and mouse lymphocytes although the latter cells were not stimulated by the lectin. Galactose specifically inhibited the agglutination and stimulation of lymphocytes by peanut agglutinin. Sequential treatment of lymphocytes with neuraminidase and beta-galactosidase markedly reduced the response of the cells to stimulation by peanut agglutinin, soybean agglutinin, and galactose oxidase. It is suggested that the same galactosyl residue may be the target for the initial step in triggering lymphocytes by the above mentioned mitogens. 相似文献
999.
Summary A soybean agglutinin was found to agglutinate mouse, rat and human cell lines transformed by viral carcinogens, but not hamster cells transformed by viral or non-viral carcinogens. Normal cells from which the transformed cells were derived were not agglutinated by this agglutinin, but they were rendered agglutinable after short incubation with trypsin or pronase. The transformed hamster cells, on the other hand, became agglutinable only after prolonged treatment with pronase. The agglutination was specifically inhibited by N-acetyl-d-galactosamine, indicating that N-acetyl-d-galactosamine-like saccharides are part of the receptor sites for soybean agglutinin on the surface membrane. Such sites exist in a cryptic form in normal cells; they are exposed in transformed mouse, rat and human cells, but become less accessible in transformed hamster cells. The receptor sites for soybean agglutinin differ from the receptors for two other plant agglutinins (wheat germ agglutinin that interacts with N-acetyl-d-glucosamine-like sites and Concanavalin A that interacts with -d-glucopyranoside-like sites) which become exposed upon transformation of all lines tested. In normal hamster cells, the receptors for all three agglutinins become exposed after incubation with trypsin, but the exposure of N-acetyl-d-galactosamine-like sites requires the longest enzyme treatment. The results indicate a difference in the location of different carbohydrate-containing sites in the surface membrane. The differences in the exposure of carbohydrate-containing sites in the membrane could not be correlated with the levels of carbohydrate-splitting glycosidases in normal and transformed cells. 相似文献
1000.
Distribution of the Phosphoenolpyruvate:Glucose Phosphotransferase System in Bacteria 总被引:43,自引:23,他引:20 下载免费PDF全文
Antonio H. Romano Susan J. Eberhard Sharon L. Dingle Thomas D. McDowell 《Journal of bacteriology》1970,104(2):808-813
A survey of the occurrence of the phosphoenolpyruvate-dependent glucose phosphotransferase system was carried out in a number of bacteria, representing both gram-positive and gram-negative facultative anaerobic and strictly aerobic types. The system was found to be present in representatives of genera that are characteristically facultative anaerobes, but the system was absent in members of those genera that are strictly aerobic. Thus, although the phosphoenolpyruvate phosphotransferase system is an important system for the transport of sugars in bacteria carrying out anaerobic glycolysis, it plays no role in sugar transport by those organisms having a strictly oxidative physiology. A fundamentally different system, probably not involving phosphorylation during transport, is indicated in this latter group. 相似文献