2,688 research outputs found

    Sex-related differences in contemporary biomarkers for heart failure:a review

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    The use of circulating biomarkers for heart failure (HF) is engrained in contemporary cardiovascular practice and provides objective information about various pathophysiological pathways associated with HF syndrome. However, biomarker profiles differ considerably among women and men. For instance, in the general population, markers of cardiac stretch (natriuretic peptides) and fibrosis (galectin-3) are higher in women, whereas markers of cardiac injury (cardiac troponins) and inflammation (sST2) are higher in men. Such differences may reflect sex-specific pathogenic processes associated with HF risk, but may also arise as a result of differences in sex hormone profiles and fat distribution. From a clinical perspective, sex-related differences in biomarker levels may affect the objectivity of biomarkers in HF management because what is considered to be 'normal' in one sex may not be so in the other. The objectives of this review are, therefore: (i) to examine the sex-specific dynamics of clinically relevant HF biomarkers in the general population, as well as in HF patients; (ii) to discuss the overlap between sex-related and obesity-related effects, and (iii) to identify knowledge gaps to stimulate research on sex-related differences in HF

    Reconsider radiation exposure from imaging during immune checkpoint inhibitor trials to reduce risk of secondary cancers in long-term survivors?

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    Immune checkpoint inhibitors (ICI) have improved outcomes for patients with advanced cancers, and results in increasing numbers of long-term survivors. For registration studies, progression-free survival and disease-free survival often serve as primary endpoints. This requires repeated computed tomography (CT) scans for tumour imaging which might lead to major radiation exposure. To determine this, all immune checkpoint inhibitors trials that led to FDA approval were retrieved up to July 29, 2019. From the available protocols, imaging modalities and schedules used in each trial were identified. The anticipated cumulative number of scans made after 1, 3, 5, and 10 years study participation were calculated. The percentage of lifetime attributable cancer risk was calculated using the Biological Effects of Ionizing Radiation VII report. Fifty-one trials were identified, from which 39 protocols were retrieved. Four were adjuvant trials. All protocols required repeated chest-abdomen imaging and specified CT scans as preferred imaging modality. Median calculated cumulative numbers of chest-abdomen CT scans after 1, 3, 5, and 10 years study participation were 7, 16, 24 and 46, respectively. For ages 20-70 years at study entry, the average lifetime attributable cancer risk after 1 year of study participation ranged from 1.11 to 0.40% for men and from 1.87 to 0.46% for women. At 10 years study participation, this risk increased to a range of 5.91 to 1.96% for men and 9.64 to 2.32% for women. Given high imaging radiation exposure for long-term survivors in current ICI trials an adaptive imaging interval and imaging termination rules should be considered for long-term survivors

    Photochromism in Ruddlesden-Popper copper-based perovskites:A light-induced change of coordination number at the surface

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    Ruddlesden-Popper organic-inorganic hybrid copper-based perovskites have been studied for decades owing to a variety of interesting properties, such as thermochromism and piezochromism, and the mechanisms behind these phenomena have been explained. Another possible property of these materials that has seldomly been investigated is photochromism. In this work, the photochromic properties of bis(phenethylammonium) tetrachlorocuprate (also known as phenethylammonium copper chloride) are reported for the first time. This material has attracted scientific interest owing to the fact that it shows both ferroelectric and ferromagnetic behavior. This work highlights the difference in stability between two Ruddlesden-Popper copper-based perovskites - with phenethylammonium (PEA) or methylammonium (MA) as the cations - during external stimuli. Various techniques, such as Raman and X-ray photoelectron spectroscopy, and grazing-incidence wide-angle X-ray scattering, combined with optical studies, were used to investigate the underlying photochemical processes at a molecular level. It is found that for the PEA compound, ultraviolet illumination causes a color change from yellow to brown. This is the result of two independent events, namely a Cu2+ reduction reaction and a transition from an octahedral copper-chloride structure to square-planar CuCl42-. After illumination, the material (brown color) is unstable in air, which is evident from a color change back to yellow. Interestingly, the similar compound bis(methylammonium) tetrachlorocuprate does not display photochromic behavior, which is attributed to the different nature of the two organic cations

    Defect ferromagnetism induced by lower valence cation doping:Li-doped SnO(2)nanoparticles

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    To explore the role of Li in establishing room-temperature ferromagnetism in SnO2, the structural, electronic and magnetic properties of Li-doped SnO(2)compounds were studied for different size regimes, from nanoparticles to bulk crystals. Li-doped nanoparticles show ferromagnetic ordering plus a paramagnetic contribution for particle sizes in the range of 16-51 nm, while pure SnO(2)and Li-doped compounds below and above this particular size range are diamagnetic. The magnetic moment is larger for compositions where the Li substitutes for Sn than for compositions where Li prevalently occupies interstitial sites. The observed ferromagnetic ordering in Li-doped SnO(2)nanoparticles is mainly due to the holes created when Li substitutes at a Sn site. Conversely, Li acts as an electron donor and electrons from Li may combine with holes to decrease ferromagnetism when lithium mainly occupies interstitial sites in the SnO(2)lattice

    Co-occurrence of diabetes, myocardial infarction, stroke, and cancer: quantifying age patterns in the Dutch population using health survey data

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    <p>Abstract</p> <p>Background</p> <p>The high prevalence of chronic diseases in Western countries implies that the presence of multiple chronic diseases within one person is common. Especially at older ages, when the likelihood of having a chronic disease increases, the co-occurrence of distinct diseases will be encountered more frequently. The aim of this study was to estimate the age-specific prevalence of multimorbidity in the general population. In particular, we investigate to what extent specific pairs of diseases cluster within people and how this deviates from what is to be expected under the assumption of the independent occurrence of diseases (i.e., sheer coincidence).</p> <p>Methods</p> <p>We used data from a Dutch health survey to estimate the prevalence of pairs of chronic diseases specified by age. Diseases we focused on were diabetes, myocardial infarction, stroke, and cancer. Multinomial P-splines were fitted to the data to model the relation between age and disease status (single versus two diseases). To assess to what extent co-occurrence cannot be explained by independent occurrence, we estimated observed/expected co-occurrence ratios using predictions of the fitted regression models.</p> <p>Results</p> <p>Prevalence increased with age for all disease pairs. For all disease pairs, prevalence at most ages was much higher than is to be expected on the basis of coincidence. Observed/expected ratios of disease combinations decreased with age.</p> <p>Conclusion</p> <p>Common chronic diseases co-occur in one individual more frequently than is due to chance. In monitoring the occurrence of diseases among the population at large, such multimorbidity is insufficiently taken into account.</p

    Improving gene function predictions using independent transcriptional components

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    The interpretation of high throughput sequencing data is limited by our incomplete functional understanding of coding and non-coding transcripts. Reliably predicting the function of such transcripts can overcome this limitation. Here we report the use of a consensus independent component analysis and guilt-by-association approach to predict over 23,000 functional groups comprised of over 55,000 coding and non-coding transcripts using publicly available transcriptomic profiles. We show that, compared to using Principal Component Analysis, Independent Component Analysis-derived transcriptional components enable more confident functionality predictions, improve predictions when new members are added to the gene sets, and are less affected by gene multi-functionality. Predictions generated using human or mouse transcriptomic data are made available for exploration in a publicly available web portal. Our understanding of the function of many transcripts is still incomplete, limiting the interpretability of transcriptomic data. Here the authors use consensus-independent component analysis, together with a guilt-by-association approach, to improve the prediction of gene function

    Relationship between body mass index, cardiovascular biomarkers and incident heart failure

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    BACKGROUND: There are limited data examining whether body-mass index (BMI) influences the association between cardiovascular biomarkers and incident heart failure (HF). METHODS AND RESULTS: Thirteen biomarkers representing key HF domains were measured: N-terminal-pro-B-type natriuretic peptide (NT-proBNP), mid-regional-pro-A-type natriuretic peptide (MR-proANP), cardiac troponin-T (cTnT), C-reactive protein, procalcitonin, galectin-3, C-terminal pro-endothelin-1 (CT-pro-ET-1), mid-regional pro-adrenomedullin, plasminogen activator inhibitor-1, copeptin, renin, aldosterone and cystatin-C. Associations of biomarkers with BMI were examined using linear regression models, and with incident HF using Cox regression models. We selected biomarkers significantly associated with incident HF, and evaluated whether BMI modified these associations. RESULTS: Among 8202 individuals, 41% were overweight (BMI 25-30kg/m2 ), and 16% were obese (BMI≥30kg/m2 ). Mean age of the cohort was 49 years (range 28-75), and 50% were women. All biomarkers except renin were associated with BMI: inverse associations were observed with NT-proBNP, MR-proANP, CT-pro-ET-1 and aldosterone whereas positive associations were observed with the remaining biomarkers (Pall ≤0.001). During 11.3±3.1 years follow-up, 357 HF events were recorded. Only NT-proBNP, MR-proANP and cTnT remained associated with incident HF (P0.1). Combined NT-proBNP and cTnT measurements modestly improved performance metrics of the clinical HF model in overweight (ΔC-statistic=0.024; LHRχ2 =38; P<0.001) and in obese (ΔC-statistic=0.020; LHRχ2 =32; P<0.001) individuals. CONCLUSIONS: Plasma concentrations of several cardiovascular biomarkers are influenced by obesity. Only NT-proBNP, MR-proANP and cTnT were associated with incident HF, and BMI did not modify these associations. A combination of NT-proBNP and cTnT improves HF risk prediction in overweight and in obese individuals. This article is protected by copyright. All rights reserved

    Serotonin and Dopamine Receptor Expression in Solid Tumours Including Rare Cancers

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    In preclinical studies serotonin stimulates and dopamine inhibits tumour growth and angiogenesis. Information regarding serotonin and dopamine receptor (5-HTR and DRD) expression in human cancers is limited. Therefore, we screened a large tumour set for receptor mRNA overexpression using functional genomic mRNA (FGmRNA) profiling, and we analysed protein expression and location of 5-HTR1B, 5-HTR2B, DRD1, and DRD2 with immunohistochemistry in different tumour types. With FGmRNA profiling 11,756 samples representing 43 tumour types were compared to 3,520 normal tissue samples to analyse receptor overexpression. 5-HTR2B overexpression was present in many tumour types, most frequently in uveal melanomas (56%). Receptor overexpression in rare cancers included 5-HTR1B in nasopharyngeal carcinoma (17%), DRD1 in ependymoma (30%) and synovial sarcoma (21%), and DRD2 in astrocytoma (13%). Immunohistochemistry demonstrated high 5-HTR2B protein expression on melanoma and gastro-intestinal stromal tumour cells and endothelial cells of colon, ovarian, breast, renal and pancreatic tumours. 5-HTR1B expression was predominantly low. High DRD2 protein expression on tumour cells was observed in 48% of pheochromocytomas, and DRD1 expression ranged from 14% in melanoma to 57% in renal cell carcinoma. In conclusion, 5-HTR1B, 5-HTR2B, DRD1, and DRD2 show mRNA overexpression in a broad spectrum of common and rare cancers. 5-HTR2B protein is frequently highly expressed in human cancers, especially on endothelial cells. These findings support further investigation of especially 5HTR2B as a potential treatment target
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