41 research outputs found

    Basal-like phenotype is not associated with patient survival in estrogen-receptor-negative breast cancers

    Get PDF
    INTRODUCTION: Basal-phenotype or basal-like breast cancers are characterized by basal epithelium cytokeratin (CK5/14/17) expression, negative estrogen receptor (ER) status and distinct gene expression signature. We studied the clinical and biological features of the basal-phenotype tumors determined by immunohistochemistry (IHC) and cDNA microarrays especially within the ER-negative subgroup. METHODS: IHC was used to evaluate the CK5/14 status of 445 stage II breast cancers. The gene expression signature of the CK5/14 immunopositive tumors was investigated within a subset (100) of the breast tumors (including 50 ER-negative tumors) with a cDNA microarray. Survival for basal-phenotype tumors as determined by CK5/14 IHC and gene expression signature was assessed. RESULTS: From the 375 analyzable tumor specimens, 48 (13%) were immunohistochemically positive for CK5/14. We found adverse distant disease-free survival for the CK5/14-positive tumors during the first years (3 years hazard ratio (HR) 2.23, 95% confidence interval (CI) 1.17 to 4.24, p = 0.01; 5 years HR 1.80, 95% CI 1.02 to 3.15, p = 0.04) but the significance was lost at the end of the follow-up period (10 years HR 1.43, 95% CI 0.84 to 2.43, p = 0.19). Gene expression profiles of immunohistochemically determined CK5/14-positive tumors within the ER-negative tumor group implicated 1,713 differently expressed genes (p < 0.05). Hierarchical clustering analysis with the top 500 of these genes formed one basal-like and a non-basal-like cluster also within the ER-negative tumor entity. A highly concordant classification could be constructed with a published gene set (Sorlie's intrinsic gene set, concordance 90%). Both gene sets identified a basal-like cluster that included most of the CK5/14-positive tumors, but also immunohistochemically CK5/14-negative tumors. Within the ER-negative tumor entity there was no survival difference between the non-basal and basal-like tumors as identified by immunohistochemical or gene-expression-based classification. CONCLUSION: Basal cytokeratin-positive tumors have a biologically distinct gene expression signature from other ER-negative tumors. Even if basal cytokeratin expression predicts early relapse among non-selected tumors, the clinical outcome of basal tumors is similar to non-basal ER-negative tumors. Immunohistochemically basal cytokeratin-positive tumors almost always belong to the basal-like gene expression profile, but this cluster also includes few basal cytokeratin-negative tumors

    Stimulant Reduction Intervention using Dosed Exercise (STRIDE) - CTN 0037: Study protocol for a randomized controlled trial

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>There is a need for novel approaches to the treatment of stimulant abuse and dependence. Clinical data examining the use of exercise as a treatment for the abuse of nicotine, alcohol, and other substances suggest that exercise may be a beneficial treatment for stimulant abuse, with direct effects on decreased use and craving. In addition, exercise has the potential to improve other health domains that may be adversely affected by stimulant use or its treatment, such as sleep disturbance, cognitive function, mood, weight gain, quality of life, and anhedonia, since it has been shown to improve many of these domains in a number of other clinical disorders. Furthermore, neurobiological evidence provides plausible mechanisms by which exercise could positively affect treatment outcomes. The current manuscript presents the rationale, design considerations, and study design of the National Institute on Drug Abuse (NIDA) Clinical Trials Network (CTN) CTN-0037 Stimulant Reduction Intervention using Dosed Exercise (STRIDE) study.</p> <p>Methods/Design</p> <p>STRIDE is a multisite randomized clinical trial that compares exercise to health education as potential treatments for stimulant abuse or dependence. This study will evaluate individuals diagnosed with stimulant abuse or dependence who are receiving treatment in a residential setting. Three hundred and thirty eligible and interested participants who provide informed consent will be randomized to one of two treatment arms: Vigorous Intensity High Dose Exercise Augmentation (DEI) or Health Education Intervention Augmentation (HEI). Both groups will receive TAU (i.e., usual care). The treatment arms are structured such that the quantity of visits is similar to allow for equivalent contact between groups. In both arms, participants will begin with supervised sessions 3 times per week during the 12-week acute phase of the study. Supervised sessions will be conducted as one-on-one (i.e., individual) sessions, although other participants may be exercising at the same time. Following the 12-week acute phase, participants will begin a 6-month continuation phase during which time they will attend one weekly supervised DEI or HEI session.</p> <p>Clinical Trials Registry</p> <p>ClinicalTrials.gov, <a href="http://www.clinicaltrials.gov/ct2/show/NCT01141608">NCT01141608</a></p> <p><url>http://clinicaltrials.gov/ct2/show/NCT01141608?term=Stimulant+Reduction+Intervention+using+Dosed+Exercise&rank=1</url></p

    Structure-based drug discovery for combating influenza virus by targeting the PA?PB1 interaction

    Get PDF
    Influenza virus infections are serious public health concerns throughout the world. The development of compounds with novel mechanisms of action is urgently required due to the emergence of viruses with resistance to the currently-approved anti-influenza viral drugs. We performed in silico screening using a structure-based drug discovery algorithm called Nagasaki University Docking Engine (NUDE), which is optimised for a GPU-based supercomputer (DEstination for Gpu Intensive MAchine; DEGIMA), by targeting influenza viral PA protein. The compounds selected by NUDE were tested for anti-influenza virus activity using a cell-based assay. The most potent compound, designated as PA-49, is a medium-sized quinolinone derivative bearing a tetrazole moiety, and it inhibited the replication of influenza virus A/WSN/33 at a half maximal inhibitory concentration of 0.47?ÎŒM. PA-49 has the ability to bind PA and its anti-influenza activity was promising against various influenza strains, including a clinical isolate of A(H1N1)pdm09 and type B viruses. The docking simulation suggested that PA-49 interrupts the PA?PB1 interface where important amino acids are mostly conserved in the virus strains tested, suggesting the strain independent utility. Because our NUDE/DEGIMA system is rapid and efficient, it may help effective drug discovery against the influenza virus and other emerging viruses

    Authenticating the Presence of a Relativistic Massive Black Hole Binary in OJ 287 Using Its General Relativity Centenary Flare: Improved Orbital Parameters

    Get PDF
    Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show that observations associated with the binary black hole (BBH) central engine of blazar OJ 287 demand the inclusion of gravitational radiation reaction effects beyond the quadrupolar order. It turns out that even the effects of certain hereditary contributions to GW emission are required to predict impact flare timings of OJ 287. We develop an approach that incorporates this effect into the BBH model for OJ 287. This allows us to demonstrate an excellent agreement between the observed impact flare timings and those predicted from ten orbital cycles of the BBH central engine model. The deduced rate of orbital period decay is nine orders of magnitude higher than the observed rate in PSR 1913+16, demonstrating again the relativistic nature of OJ 287's central engine. Finally, we argue that precise timing of the predicted 2019 impact flare should allow a test of the celebrated black hole "no-hair theorem" at the 10% level

    Stochastic Modeling of Multiwavelength Variability of the Classical BL Lac Object OJ287 on Timescales Ranging from Decades to Hours

    Get PDF
    We present the results of our power spectral density analysis for the BL Lac object OJ 287, utilizing the Fermi-LAT survey at high-energy.-rays, Swift-XRT in X-rays, several ground-based telescopes and the Kepler satellite in the optical, and radio telescopes at GHz frequencies. The light curves are modeled in terms of continuous-time autoregressive moving average (CARMA) processes. Owing to the inclusion of the Kepler data, we were able to construct for the first time the optical variability power spectrum of a blazar without any gaps across similar to 6 dex in temporal frequencies. Our analysis reveals that the radio power spectra are of a colored-noise type on timescales ranging from tens of years down to months, with no evidence for breaks or other spectral features. The overall optical power spectrum is also consistent with a colored noise on the variability timescales ranging from 117 years down to hours, with no hints of any quasi-periodic oscillations. The X-ray power spectrum resembles the radio and optical power spectra on the analogous timescales ranging from tens of years down to months. Finally, the.-ray power spectrum is noticeably different from the radio, optical, and X-ray power spectra of the source: we have detected a characteristic relaxation timescale in the Fermi-LAT data, corresponding to similar to 150 days, such that on timescales longer than this, the power spectrum is consistent with uncorrelated (white) noise, while on shorter variability timescales there is correlated (colored) noise

    Bloggende Medizinstudierende: Eine qualitative Analyse

    Get PDF
    Purpose: Blogging is an increasingly popular method of sharing and reflecting on experiences of medical students in the World Wide Web with a potentially global learning community. The authors are not aware of studies that specifically examined blogs by medical students and thus for the first time investigated the type of experiences and impressions that emerged from these blogs with relevance for medical students and medical educators.Method: This was a qualitative study. Initially 75 blogs were identified. 33 blogs with a total of 1228 English and 337 German blog entries met the inclusion criteria and were analyzed. We started with line-by-line coding and switched to focused coding using constant comparative analysis to create a categorical framework for blogs.Results: Medical students use blogs to write and reflect about a large variety of issues related to medical school. Major emerging themes included the preparation for written and oral high-stakes exams, experiences during clinical rotations, dealing with distressing situations during medical school, and social life of students beyond medical school. Conclusions: Our findings suggest that blogs are a potentially useful tool for medical students to reflect on their experiences during medical school as well as for medical educators to better understand how students perceive their time in medical school. The educational benefit of blogging might even be increased if trained medical educators would help to facilitate meaningful and targeted discussions emerging from blog entries and comment on students' learning challenges with the chance to reach a large community of learners.Einleitung: Bloggen ist eine unter Medizinstudierenden zunehmend verbreitete Methode, Erfahrungen ĂŒber das Internet mit einer weltweiten "Learning Community" auszutauschen. Trotz intensiver Recherche sind den Autoren keine Studien bekannt, in denen spezifisch Blogs von Medizinstudierenden qualitativ analysiert wurden. Im Folgenden werden Kategorien und Themen aus diesen BlogeintrĂ€gen beschrieben und ihre medizindidaktische Bedeutung fĂŒr Medizinstudierende und Lehrende diskutiert.Methoden: In der vorliegenden qualitativen Studie wurden ursprĂŒnglich 75 von Medizinstudierenden verfasste Blogs identifiziert. 33 Blogs mit insgesamt 1228 englischen und 337 deutschen EintrĂ€gen erfĂŒllten die Einschlusskriterien und wurden analysiert. Mit Hilfe einer komparativen Analysemethode wurden die BlogeintrĂ€ge zunĂ€chst Zeile fĂŒr Zeile und anschließend fokussiert kodiert. Die emergierenden Themen und Unterthemen wurden in ĂŒbergeordneten Kategorien zusammengefasst.Ergebnisse: Medizinstudierende verwenden Blogs, um ĂŒber eine große Vielfalt an Erfahrungen wĂ€hrend des Medizinstudiums zu berichten und diese zu reflektieren. Vorbereitung auf schriftliche und mĂŒndliche Examina, Erfahrungen wĂ€hrend klinischer Praktika, der Umgang mit belastenden Situationen wĂ€hrend des Studiums und das Sozialleben jenseits des Studiums waren Hauptthemen.Schlussfolgerung: Unsere Ergebnisse weisen darauf hin, dass Blogs fĂŒr Medizinstudierende möglicherweise hilfreich sind, um Erfahrungen zu reflektieren. ZusĂ€tzlich können Lehrende auf diesem Weg wertvolle Einblicke in die studentische Wahrnehmung der medizinischen Ausbildung erhalten.Die Bedeutung von Blogs in der medizinischen Ausbildung könnte durch gezieltes Kommentieren von BlogeintrĂ€gen durch Lehrende erhöht werden. Von diesem Dialog könnte auch eine örtlich unabhĂ€ngige "Learning Community" profitieren
    corecore