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Antithrombotic management of patients with atrial fibrillation (AF) undergoing coronary stenting is complicated by the need for anticoagulant therapy for stroke prevention and dual antiplatelet therapy for prevention of stent thrombosis and coronary events. Triple antithrombotic therapy, typically comprising warfarin, aspirin, and clopidogrel, is associated with a high risk of bleeding. A modest-sized trial of oral anticoagulation with warfarin and clopidogrel without aspirin showed improvements in both bleeding and thrombotic events compared with triple therapy, but large trials are lacking. The RE-DUAL PCI trial (NCT 02164864) is a phase 3b, a strategy of prospective, randomized, open-label, blinded-endpoint trial. The main objective is to evaluate dual antithrombotic therapy with dabigatran etexilate (110 or 150 mg twice daily) and a P2Y12 inhibtor (either clopidogrel or ticagrelor) compared with triple antithrombotic therapy with warfarin, a P2Y12 inhibtor (either clopidogrel or ticagrelor, and low-dose aspirin (for 1 or 3 months, depending on stent type) in nonvalvular AF patients who have undergone percutaneous coronary intervention with stenting. The primary endpoint is time to first International Society of Thrombosis and Hemostasis major bleeding event or clinically relevant nonmajor bleeding event. Secondary endpoints are the composite of all cause death or thrombotic events (myocardial infarction, or stroke/systemic embolism) and unplanned revascularization; death or thrombotic events; individual outcome events; death, myocardial infarction, or stroke; and unplanned revascularization. A hierarchical procedure for multiple testing will be used. The plan is to randomize ∼ 2500 patients at approximately 550 centers worldwide to try to identify new treatment strategies for this patient population.
Mitochondrial complex I is a 1MDa membrane protein complex with a central role in aerobic energy metabolism. The bioenergetic core functions are executed by 14 central subunits that are conserved from bacteria to man. Despite recent progress in structure determination, our understanding of the function of the ~30 accessory subunits associated with the mitochondrial complex is still limited. We have investigated the structure of complex I from the aerobic yeast Yarrowia lipolytica by cryo-electron microscopy. Our density map at 7.9Å resolution closely matches the 3.6-3.9Å X-ray structure of the Yarrowia lipolytica complex. However, the cryo-EM map indicated an additional subunit on the side of the matrix arm above the membrane surface, pointing away from the membrane arm. The density, which is not present in any previously described complex I structure and occurs in about 20 % of the particles, was identified as the accessory sulfur transferase subunit ST1. The Yarrowia lipolytica complex I preparation is active in generating H2S from the cysteine derivative 3-mercaptopyruvate, catalyzed by ST1. We thus provide evidence for a link between respiratory complex I and mitochondrial sulfur metabolism.
Objective: Gestational diabetes mellitus (GDM) is associated with substantial morbidity for mothers and their offspring. While clinical and basic research activities on this important disease grow constantly, there is no concise analysis of global architecture of GDM research. Hence, it was the objective of this study to assess the global scientific performance chronologically, geographically and in relation to existing research networks and gender distribution of publishing authors.
Study design: On the basis of the New Quality and Quantity Indices in Science (NewQIS) platform, scientometric methods were combined with modern visualizing techniques such as density equalizing mapping, and the Web of Science database was used to assess GDM-related entries from 1900 to 2012.
Results: Twelve thousand five hundred four GDM-related publications were identified and analyzed. The USA (4295 publications) and the UK (1354 publications) dominated the field concerning research activity, overall citations and country-specific Hirsch-Index, which quantified the impact of a country’s published research on the scientific community. Semi-qualitative indices such as country-specific citation rates ranked New Zealand and the UK at top positions. Annual collaborative publications increased steeply between the years 1990 and 2012 (71 to 1157 respectively). Subject category analysis pointed to a minor interest of public health issues in GDM research. Gender analysis in terms of publication authorship revealed a clear dominance of the male gender until 2005; then a trend towards gender equity started and the activity of female scientists grew visibly in many countries. The country-specific gender analysis revealed large differences, i.e. female scientists dominated the scientific output in the USA, whereas the majority of research was published by male authors in countries such as Japan.
Conclusion: This study provides the first global sketch of GDM research architecture. While North-American and Western-European countries were dominating the GDM-related scientific landscape, a disparity exists in terms of research output between developed and low-resource countries. Since GDM is linked to considerable mortality and morbidity of mothers and their offspring and constitutes a tremendous burden for the healthcare systems in underserved countries, our findings emphasize the need to address disparities by fostering research endeavors, public health programs and collaborative efforts in these nations.
Correlated activity of cortical neurons survives extensive removal of feedforward sensory input
(2016)
A fundamental property of brain function is that the spiking activity of cortical neurons is variable and that some of this variability is correlated between neurons. Correlated activity not due to the stimulus arises from shared input but the neuronal circuit mechanisms that result in these noise correlations are not fully understood. Here we tested in the visual system if correlated variability in mid-level area V4 of visual cortex is altered following extensive lesions of primary visual cortex (V1). To this end we recorded longitudinally the neuronal correlations in area V4 of two behaving macaque monkeys before and after a V1 lesion while the monkeys fixated a grey screen. We found that the correlations of neuronal activity survived the lesions in both monkeys. In one monkey, the correlation of multi-unit spiking signals was strongly increased in the first week post-lesion, while in the second monkey, correlated activity was slightly increased, but not greater than some week-by-week fluctuations observed. The typical drop-off of inter-neuronal correlations with cortical distance was preserved after the lesion. Therefore, as V4 noise correlations remain without feedforward input from V1, these results suggest instead that local and/or feedback input seem to be necessary for correlated activity.
Infections are an important cause for morbidity and mortality in pediatric acute myeloid leukemia (AML). We therefore characterized infectious complications in children treated according to the trial AML-BFM 2004. Patients with Down syndrome were excluded from the analysis. Data were gathered from the medical records in the hospital where the patients were treated. A total of 405 patients (203 girls; median age 8.4 years) experienced 1326 infections. Fever without identifiable source occurred in 56.1% of the patients and clinically and microbiologically documented infections in 17.5% and 32.4% of the patients, respectively. In all, 240 Gram-positive (112 viridans group streptococci) and 90 Gram-negative isolates were recovered from the bloodstream. Invasive fungal infection was diagnosed in 3% of the patients. Three children each died of Gram-negative bacteremia and invasive aspergillosis, respectively. As compared with the results of AML-BFM 93 with lower dose intensity, infection-related morbidity was slightly higher in AML-BFM 2004 (3.3. versus 2.8 infections per patient), whereas infection-related mortality significantly decreased (1.5% versus 5.4%; P=0.003). Specific anti-infective recommendations included in the treatment protocol, regular training courses for pediatric hematologists and increasing experience may be the reason for reduced infection-related mortality in children with AML. Further studies are needed to decrease infection-related morbidity.
A complex aberrant karyotype consisting of multiple unrelated cytogenetic abnormalities is associated with poor prognosis in patients with acute myeloid leukemia (AML). The European Leukemia Net classification and the UK Medical Research Council recommendation provide prognostic categories that differ in the definition of unbalanced aberrations as well as the number of single aberrations. The aim of this study on 3526 AML patients was to redefine and validate a cutoff for karyotype complexity in AML with regard to adverse prognosis. Our study demonstrated that (1) patients with a pure hyperdiploid karyotype have an adverse risk irrespective of the number of chromosomal gains, (2) patients with translocation t(9;11)(p21~22;q23) have an intermediate risk independent of the number of additional aberrations, (3) patients with greater than or equal to4 abnormalities have an adverse risk per se and (4) patients with three aberrations in the absence of abnormalities of strong influence (hyperdiploid karyotype, t(9;11)(p21~22;q23), CBF-AML, unique adverse-risk aberrations) have borderline intermediate/adverse risk with a reduced overall survival compared with patients with a normal karyotype.
DNA methylation is a major regulatory process of gene transcription, and aberrant DNA methylation is associated with various diseases including cancer. Many compounds have been reported to modify DNA methylation states. Despite increasing interest in the clinical application of drugs with epigenetic effects, and the use of diagnostic markers for genome-wide hypomethylation in cancer, large-scale screening systems to measure the effects of drugs on DNA methylation are limited. In this study, we improved the previously established fluorescence polarization-based global DNA methylation assay so that it is more suitable for application to human genomic DNA. Our methyl-sensitive fluorescence polarization (MSFP) assay was highly repeatable (inter-assay coefficient of variation = 1.5%) and accurate (r2 = 0.99). According to signal linearity, only 50–80 ng human genomic DNA per reaction was necessary for the 384-well format. MSFP is a simple, rapid approach as all biochemical reactions and final detection can be performed in one well in a 384-well plate without purification steps in less than 3.5 hours. Furthermore, we demonstrated a significant correlation between MSFP and the LINE-1 pyrosequencing assay, a widely used global DNA methylation assay. MSFP can be applied for the pre-screening of compounds that influence global DNA methylation states and also for the diagnosis of certain types of cancer.
The mitochondrial cascade hypothesis of dementia assumes mitochondrial dysfunction leading to reduced energy supply, impaired neuroplasticity, and finally cell death as one major pathomechanism underlying the continuum from brain aging over mild cognitive impairment to initial and advanced late onset Alzheimer's disease. Accordingly, improving mitochondrial function has become an important strategy to treat the early stages of this continuum. The metabolic enhancer piracetam has been proposed as possible prototype for those compounds by increasing impaired mitochondrial function and related aspects like mechanisms of neuroplasticity. We here report that piracetam at therapeutically relevant concentrations improves neuritogenesis in the human cell line SH-SY5Y over conditions mirroring the whole spectrum of age-associated cognitive decline. These effects go parallel with improvement of impaired mitochondrial dynamics shifting back fission and fusion balance to the energetically more favorable fusion site. Impaired fission and fusion balance can also be induced by a reduction of the mitochondrial permeability transition pore (mPTP) function as atractyloside which indicates the mPTP has similar effects on mitochondrial dynamics. These changes are also reduced by piracetam. These findings suggest the mPTP as an important target for the beneficial effects of piracetam on mitochondrial function.
The general assumption that brain size differences are an adequate proxy for subtler differences in brain organization turned neurobiologists toward the question why some groups of mammals such as primates, elephants, and whales have such remarkably large brains. In this meta-analysis, an extensive sample of eutherian mammals (115 species distributed in 14 orders) provided data about several different biological traits and measures of brain size such as absolute brain mass (AB), relative brain mass (RB; quotient from AB and body mass), and encephalization quotient (EQ). These data were analyzed by established multivariate statistics without taking specific phylogenetic information into account. Species with high AB tend to (1) feed on protein-rich nutrition, (2) have a long lifespan, (3) delayed sexual maturity, and (4) long and rare pregnancies with small litter sizes. Animals with high RB usually have (1) a short life span, (2) reach sexual maturity early, and (3) have short and frequent gestations. Moreover, males of species with high RB also have few potential sexual partners. In contrast, animals with high EQs have (1) a high number of potential sexual partners, (2) delayed sexual maturity, and (3) rare gestations with small litter sizes. Based on these correlations, we conclude that Eutheria with either high AB or high EQ occupy positions at the top of the network of food chains (high trophic levels). Eutheria of low trophic levels can develop a high RB only if they have small body masses.