259 research outputs found

    Reconstruction of solar activity for the last millennium using 10^{10}Be data

    Full text link
    In a recent paper (Usoskin et al., 2002a), we have reconstructed the concentration of the cosmogenic 10^{10}Be isotope in ice cores from the measured sunspot numbers by using physical models for 10^{10}Be production in the Earth's atmosphere, cosmic ray transport in the heliosphere, and evolution of the Sun's open magnetic flux. Here we take the opposite route: starting from the 10^{10}Be concentration measured in ice cores from Antarctica and Greenland, we invert the models in order to reconstruct the 11-year averaged sunspot numbers since 850 AD. The inversion method is validated by comparing the reconstructed sunspot numbers with the directly observed sunspot record since 1610. The reconstructed sunspot record exhibits a prominent period of about 600 years, in agreement with earlier observations based on cosmogenic isotopes. Also, there is evidence for the century scale Gleissberg cycle and a number of shorter quasi-periodicities whose periods seem to fluctuate in the millennium time scale. This invalidates the earlier extrapolation of multi-harmonic representation of sunspot activity over extended time intervals.Comment: Submitted to A&

    Dynamic Micropatterning Reveals Substrate-Dependent Differences in the Geometric Control of Cell Polarization and Migration

    Get PDF
    Cells are highly dynamic and adopt variable shapes and sizes. These variations are biologically important but challenging to investigate in a spatiotemporally controlled manner. Micropatterning, confining cells on microfabricated substrates with defined geometries and molecular compositions, is a powerful tool for controlling cell shape and interactions. However, conventional binary micropatterns are static and fail to address dynamic changes in cell polarity, spreading, and migration. Here, a method for dynamic micropatterning is reported, where the non-adhesive surface surrounding adhesive micropatterns is rapidly converted to support specific cell-matrix interactions while allowing simultaneous imaging of the cells. The technique is based on ultraviolet photopatterning of biotinylated polyethylene glycol-grafted poly-L-lysine, and it is simple, inexpensive, and compatible with a wide range of streptavidin-conjugated ligands. Experiments using biotinylation-based dynamic micropatterns reveal that distinct extracellular matrix ligands and bivalent integrin-clustering antibodies support different degrees of front-rear polarity in human glioblastoma cells, which correlates to altered directionality and persistence upon release and migration on fibronectin. Unexpectedly, however, neither an asymmetric cell shape nor centrosome orientation can fully predict the future direction of migration. Taken together, biotinylation-based dynamic micropatterns allow easily accessible and highly customizable control over cell morphology and motility

    Magnetism of ZnO Nanoparticles: Dependence on Crystallite Size and Surfactant Coating

    Get PDF
    Many recent reports on magnetism in otherwise nonmagnetic oxides have demonstrated that nanoparticle size, surfactant coating, or doping with magnetic ions produces room-temperature ferromagnetism. Specifically, ZnO has been argued to be a room-temperature ferromagnet through all three of these methods in various experimental studies. For this reason, we have prepared a series of 1% Fe doped ZnO nanoparticle samples using a single forced hydrolysis co-precipitation synthesis method from the same precursors, while varying size (6 – 15 nm) and surface coating concentration to study the combined effects of these two parameters. Size was controlled by modifying the water concentration. Surfactant coating was adjusted by varying the concentration of poly acrylic acid (PAA) in solution. Samples were characterized by x-ray diffraction, transmission electron microscopy, x-ray photoelectron spectroscopy, optical absorptance spectroscopy, and magnetometry. No clear systematic effect on magnetization was observed as a function of surfactant coating, while evidence for a direct dependence of magnetization on the crystallite size is apparent

    Follow-Up of Cancer Patients Receiving Anti-PD-(L)1 Therapy Using an Electronic Patient-Reported Outcomes Tool (KISS): Prospective Feasibility Cohort Study

    Get PDF
    Background: Immune checkpoint inhibitors (ICIs) have become a standard of care for various tumor types. Their unique spectrum of side effects demands continuous and long-lasting assessment of symptoms. Electronic patient-reported outcome (ePRO) follow-up has been shown to improve survival and quality of life of cancer patients treated with chemotherapy.Objective: This study aimed to investigate whether ePRO follow-up of cancer patients treated with ICIs is feasible. The study analyzed (1) the variety of patient reported symptoms, (2) etiology of alerts, (3) symptom correlations, and (4) patient compliance.Methods: In this prospective, one-arm, multi-institutional study, we recruited adult cancer patients whose advanced cancer was treated with anti-programmed cell death protein 1 (PD)-ligand (L)1 agents in outpatient settings. The ePRO tool consisted of a weekly questionnaire evaluating the presence of typical side effects, with an algorithm assessing the severity of the symptom according to National Cancer Institute Common Terminology Criteria for Adverse Events and an urgency algorithm sending alerts to the care team. A patient experience survey was conducted monthly. The patients were followed up to 6 months or until disease progression.Results: A total of 889 symptom questionnaires was completed by 37 patients (lung cancer, n=15; melanoma, n=9; genitourinary cancer, n=9; head and neck cancer, n=4). Patients showed good adherence to ePRO follow-up. The most common grade 1 symptoms were fatigue (28%) and itching (13%), grade 2 symptoms were loss of appetite (12%) and nausea (12%), and grade 3-4 symptoms were cough (6%) and loss of appetite (4%). The most common reasons for alerts were loss of appetite and shortness of breath. In the treatment benefit analysis, positive correlations were seen between clinical benefit and itching as well as progressive disease and chest pain.Conclusions: According to the results, ePRO follow-up of cancer patients receiving ICIs is feasible. ePROs capture a wide range of symptoms. Some symptoms correlate to treatment benefit, suggesting that individual prediction models could be generated

    Integrins are not essential for entry of coxsackievirus A9 into SW480 human colon adenocarcinoma cells

    Get PDF
    Background: Coxsackievirus A9 (CV-A9) is a pathogenic enterovirus type within the family Picornaviridae. CV-A9 infects A549 human epithelial lung carcinoma cells by attaching to the aVβ6 integrin receptor through a highly conserved Arg-Gly-Asp (RGD) motif, which is located at the exposed carboxy-terminus of the capsid protein VP1 in all studied clinical isolates. However, genetically-modified CV-A9 that lacks the RGD motif (CV-A9-RGDdel) has been shown to be infectious in some cell lines but not in A549, suggesting that RGD-mediated integrin binding is not always essential for efficient entry of CV-A9.   Methods: Two cell lines, A549 and SW480, were used in the study. SW480 was the study object for the integrin-independent entry and A549 was used as the control for integrin-dependent entry. Receptor levels were quantitated by cell sorting and quantitative PCR. Antibody blocking assay and siRNA silencing of receptor-encoding genes were used to block virus infection. Peptide phage display library was used to identify peptide binders to CV-A9. Immunofluorescence and confocal microscopy were used to visualize the virus infection in the cells.   Results: We investigated the receptor use and early stages of CV-A9 internalization to SW480 human epithelial colon adenocarcinoma cells. Contrary to A549 infection, we showed that both CV-A9 and CV-A9-RGDdel internalized into SW480 cells and that function-blocking anti-αV integrin antibodies had no effect on the binding and entry of CV-A9. Whereas siRNA silencing of β6 integrin subunit had no influence on virus infection in SW480, silencing of β2-microglobulin (b2M) inhibited the virus infection in both cell lines. By using a peptide phage display screening, the virus-binding peptide identical to the N-terminal sequence of HSPA5 protein was identified and shown to block the virus infection in both A549 and SW480 cell lines. HSPA5 was also found to co-localize with CV-A9 at the SW480 cell periphery during the early stages of infection by confocal microscopy.   Conclusions: The data suggest that while aVβ6 integrin is essential for CV-A9 in A549 cell line, it is not required in SW480 cell line in which β2M and HSPA5 alone are sufficient for CV-A9 infection. This suggests that the choice of CV-A9 receptor(s) is dependent on the tissue/cellular environment.</p

    A Millennium Scale Sunspot Number Reconstruction: Evidence For an Unusually Active Sun Since the 1940's

    Full text link
    The extension of the sunspot number series backward in time is of considerable interest for dynamo theory, solar, stellar, and climate research. We have used records of the Be-10 concentration in polar ice to reconstruct the average sunspot activity level for the period between the year 850 to the pr esent. Our method uses physical models for processes connecting the Be-10 concentration with the sunspot number. The reconstruction shows reliably that the period of high solar activity during the last 60 years is unique throughout the past 1150 years. This nearly triples the time interval for which such a statement could be made previouslyComment: 4 pages, LaTeX, revtex4 macros; Phys. Rev. Let., in pres

    Sleep-wake sensitive mechanisms of adenosine release in the basal forebrain of rodents : an in vitro study

    Get PDF
    Adenosine acting in the basal forebrain is a key mediator of sleep homeostasis. Extracellular adenosine concentrations increase during wakefulness, especially during prolonged wakefulness and lead to increased sleep pressure and subsequent rebound sleep. The release of endogenous adenosine during the sleep-wake cycle has mainly been studied in vivo with microdialysis techniques. The biochemical changes that accompany sleep-wake status may be preserved in vitro. We have therefore used adenosine-sensitive biosensors in slices of the basal forebrain (BFB) to study both depolarization-evoked adenosine release and the steady state adenosine tone in rats, mice and hamsters. Adenosine release was evoked by high K+, AMPA, NMDA and mGlu receptor agonists, but not by other transmitters associated with wakefulness such as orexin, histamine or neurotensin. Evoked and basal adenosine release in the BFB in vitro exhibited three key features: the magnitude of each varied systematically with the diurnal time at which the animal was sacrificed; sleep deprivation prior to sacrifice greatly increased both evoked adenosine release and the basal tone; and the enhancement of evoked adenosine release and basal tone resulting from sleep deprivation was reversed by the inducible nitric oxide synthase (iNOS) inhibitor, 1400 W. These data indicate that characteristics of adenosine release recorded in the BFB in vitro reflect those that have been linked in vivo to the homeostatic control of sleep. Our results provide methodologically independent support for a key role for induction of iNOS as a trigger for enhanced adenosine release following sleep deprivation and suggest that this induction may constitute a biochemical memory of this state

    Coaches' Health Promotion Activity and Substance Use in Youth Sports

    Get PDF
    There is an increasing amount of evidence suggesting youth sports clubs are an important setting for health promotion. Adolescents in sport club settings can benefit from exposures of positive and negative consequences to health. To better understand the sport club context and coaches' health promotion activity in substance use prevention, this study compares sport club members with non-members aged between 14-16 years old on their experience and use of alcohol, smoking and snuff and coaches' health promotion activity on substances. Methods: Adolescents (n = 671) from sports clubs and from matched schools (n = 1442) were recruited in this study. Multiple binary logistic regressions were performed on substance use. Results: Higher prevalence of substance use was associated with discussions of substances, often held by coaches. Significantly fewer girls who are sport club members had experiences in alcohol, smoking or snuff than their non-member counter-parts, the differences among boys varied by substance. Fewer sport club members experienced smoking than non-members. More boys used snuff than girls. Conclusions: The most salient points for health promotion were that girls who were sport club members used fewer substances and for boys the picture was more complicated. Coaches could be using reactive strategies through informal learning to address substance use in clubs, although more effective training on substance use for coaches is needed

    Insomnia is a frequent finding in adults with Asperger syndrome

    Get PDF
    BACKGROUND: Asperger syndrome (AS) is a neurodevelopmental disorder belonging to autism spectrum disorders with prevalence rate of 0,35% in school-age children. It has been most extensively studied in childhood while there is scarcity of reports concerning adulthood of AS subjects despite the lifelong nature of this syndrome. In children with Asperger syndrome the initiation and continuity of sleep is disturbed because of the neuropsychiatric deficits inherent of AS. It is probable that sleep difficulties are present in adulthood as well. Our hypothesis was that adults with AS suffer from difficulty in initiating and maintaining sleep and nonrestorative sleep (insomnia). METHODS: 20 AS without medication were compared with 10 healthy controls devoid of neuropsychiatric anamnesis. Clinical examination, blood test battery and head MRI excluded confounding somatic illnesses. Structured psychiatric interview for axis-I and axis-II disorders were given to both groups as well as Beck Depression Inventory and Wechsler adult intelligence scale, revised version. Sleep quality was assessed with sleep questionnaire, sleep diary during 6 consecutive days and description of possible sleep problems by the participants own words was requested. RESULTS: compared with controls and with normative values of good sleep, AS adults had frequent insomnia. In sleep questionnaire 90% (18/20), in sleep diary 75% (15/20) and in free description 85% (17/20) displayed insomnia. There was a substantial psychiatric comorbidity with only 4 AS subject devoid of other axis-I or axis-II disorders besides AS. Also these persons displayed insomnia. It can be noted that the distribution of psychiatric diagnoses in AS subjects was virtually similar to that found among patient with chronic insomnia. CONCLUSIONS: the neuropsychiatric deficits inherent of AS predispose both to insomnia and to anxiety and mood disorders. Therefore a careful assessment of sleep quality should be an integral part of the treatment plan in these individuals. Conversely, when assessing adults with chronic insomnia the possibility of autism spectrum disorders as one of the potential causes of this condition should be kept in mind

    Pembrolizumab for Treatment-Refractory Metastatic Castration-Resistant Prostate Cancer: Multicohort, Open-Label Phase II KEYNOTE-199 Study

    Get PDF
    PURPOSE: Pembrolizumab has previously shown antitumor activity against programmed death ligand 1 (PD-L1)-positive metastatic castration-resistant prostate cancer (mCRPC). Here, we assessed the antitumor activity and safety of pembrolizumab in three parallel cohorts of a larger mCRPC population. METHODS: The phase II KEYNOTE-199 study included three cohorts of patients with mCRPC treated with docetaxel and one or more targeted endocrine therapies. Cohorts 1 and 2 enrolled patients with RECIST-measurable PD-L1-positive and PD-L1-negative disease, respectively. Cohort 3 enrolled patients with bone-predominant disease, regardless of PD-L1 expression. All patients received pembrolizumab 200 mg every 3 weeks for up to 35 cycles. The primary end point was objective response rate per RECIST v1.1 assessed by central review in cohorts 1 and 2. Secondary end points included disease control rate, duration of response, overall survival (OS), and safety. RESULTS: Two hundred fifty-eight patients were enrolled: 133 in cohort 1, 66 in cohort 2, and 59 in cohort 3. Objective response rate was 5% (95% CI, 2% to 11%) in cohort 1 and 3% (95% CI, = 21.8 months) and 10.6 months (range, 4.4 to 16.8 months), respectively. Disease control rate was 10% in cohort 1, 9% in cohort 2, and 22% in cohort 3. Median OS was 9.5 months in cohort 1, 7.9 months in cohort 2, and 14.1 months in cohort 3. Treatment-related adverse events occurred in 60% of patients, were of grade 3 to 5 severity in 15%, and led to discontinuation of treatment in 5%. CONCLUSION: Pembrolizumab monotherapy shows antitumor activity with an acceptable safety profile in a subset of patients with RECIST-measurable and bone-predominant mCRPC previously treated with docetaxel and targeted endocrine therapy. Observed responses seem to be durable, and OS estimates are encouraging
    • …
    corecore