137 research outputs found
Study protocol: NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC trial): a randomised controlled trial
Introduction Congenital heart disease (CHD) is a major cause of infant mortality. Many infants with CHD require corrective surgery with most operations requiring cardiopulmonary bypass (CPB). CPB triggers a systemic inflammatory response which is associated with low cardiac output syndrome (LCOS), postoperative morbidity and mortality. Delivery of nitric oxide (NO) into CPB circuits can provide myocardial protection and reduce bypass-induced inflammation, leading to less LCOS and improved recovery. We hypothesised that using NO during CPB increases ventilator-free days (VFD) (the number of days patients spend alive and free from invasive mechanical ventilation up until day 28) compared with standard care. Here, we describe the NITRIC trial protocol. Methods and analysis The NITRIC trial is a randomised, double-blind, controlled, parallel-group, two-sided superiority trial to be conducted in six paediatric cardiac surgical centres. One thousand three-hundred and twenty infants <2 years of age undergoing cardiac surgery with CPB will be randomly assigned to NO at 20 ppm administered into the CPB oxygenator for the duration of CPB or standard care (no NO) in a 1:1 ratio with stratification by age (<6 and ≥6 weeks), single ventricle physiology (Y/N) and study centre. The primary outcome will be VFD to day 28. Secondary outcomes include a composite of LCOS, need for extracorporeal membrane oxygenation or death within 28 days of surgery; length of stay in intensive care and in hospital; and, healthcare costs. Analyses will be conducted on an intention-to-treat basis. Preplanned secondary analyses will investigate the impact of NO on host inflammatory profiles postsurgery. Ethics and dissemination The study has ethical approval (HREC/17/QRCH/43, dated 26 April 2017), is registered in the Australian New Zealand Clinical Trials Registry (ACTRN12617000821392) and commenced recruitment in July 2017. The primary manuscript will be submitted for publication in a peer-reviewed journal. Trial registration number ACTRN12617000821392.</p
Rosiglitazone Decreases C-Reactive Protein to a Greater Extent Relative to Glyburide and Metformin Over 4 Years Despite Greater Weight Gain: Observations from A Diabetes Outcome Progression Trial (ADOPT)
OBJECTIVE: C-reactive protein (CRP) is closely associated with obesity and cardiovascular disease in both diabetic and nondiabetic populations. In the short term, commonly prescribed antidiabetic agents have different effects on CRP; however, the long-term effects of those agents are unknown. RESEARCH DESIGN AND METHODS: In A Diabetes Outcome Progression Trial (ADOPT), we examined the long-term effects of rosiglitazone, glyburide, and metformin on CRP and the relationship among CRP, weight, and glycemic variables in 904 subjects over 4 years. RESULTS: Baseline CRP was significantly correlated with homeostasis model assessment of insulin resistance (HOMA-IR), A1C, BMI, waist circumference, and waist-to-hip ratio. CRP reduction was greater in the rosiglitazone group by -47.6% relative to glyburide and by -30.5% relative to metformin at 48 months. Mean weight gain from baseline (at 48 months) was 5.6 kg with rosiglitazone, 1.8 kg with glyburide, and -2.8 kg with metformin. The change in CRP from baseline to 12 months was correlated positively with change in BMI in glyburide (r = 0.18) and metformin (r = 0.20) groups but not in the rosiglitazone (r = -0.05, NS) group. However, there was no longer a significant correlation between change in CRP and change in HOMA-IR, A1C, or waist-to-hip ratio in any of the three treatment groups. CONCLUSIONS: Rosiglitazone treatment was associated with durable reductions in CRP independent of changes in insulin sensitivity, A1C, and weight gain. CRP in the glyburide and metformin groups was positively associated with changes in weight, but this was not the case with rosiglitazone
Natural Products from the Lithistida: A Review of the Literature since 2000
Lithistid sponges are known to produce a diverse array of compounds ranging from polyketides, cyclic and linear peptides, alkaloids, pigments, lipids, and sterols. A majority of these structurally complex compounds have very potent and interesting biological activities. It has been a decade since a thorough review has been published that summarizes the literature on the natural products reported from this amazing sponge order. This review provides an update on the current taxonomic classification of the Lithistida, describes structures and biological activities of 131 new natural products, and discusses highlights from the total syntheses of 16 compounds from marine sponges of the Order Lithistida providing a compilation of the literature since the last review published in 2002
Confronting Uncertainty in Wildlife Management: Performance of Grizzly Bear Management
Scientific management of wildlife requires confronting the complexities of natural and social systems. Uncertainty poses a central problem. Whereas the importance of considering uncertainty has been widely discussed, studies of the effects of unaddressed uncertainty on real management systems have been rare. We examined the effects of outcome uncertainty and components of biological uncertainty on hunt management performance, illustrated with grizzly bears (Ursus arctos horribilis) in British Columbia, Canada. We found that both forms of uncertainty can have serious impacts on management performance. Outcome uncertainty alone – discrepancy between expected and realized mortality levels – led to excess mortality in 19% of cases (population-years) examined. Accounting for uncertainty around estimated biological parameters (i.e., biological uncertainty) revealed that excess mortality might have occurred in up to 70% of cases. We offer a general method for identifying targets for exploited species that incorporates uncertainty and maintains the probability of exceeding mortality limits below specified thresholds. Setting targets in our focal system using this method at thresholds of 25% and 5% probability of overmortality would require average target mortality reductions of 47% and 81%, respectively. Application of our transparent and generalizable framework to this or other systems could improve management performance in the presence of uncertainty.
 
Photoactive assemblies of organic compounds and biomolecules: drug-protein supramolecular systems
[EN] The properties of singlet and triplet excited states are strongly medium-dependent.
Hence, these species constitute valuable tools as reporters to probe compartmentalised
microenvironments, including drug@protein supramolecular systems. In the present
review, the attention is focused on the photophysical properties of the probe drugs
(rather than those of the protein chromophores) using transport proteins (serum
albumins and 1-acid glycoproteins) as hosts. Specifically, fluorescence measurements
allow investigating the structural and dynamic properties of biomolecules or their
complexes. Thus, the emission quantum yields and the decay kinetics of the drug singlet
excited states provide key information to determine important parameters such as the
stoichiometry of the complex, the binding constant, the relative degrees of occupancy of
the different compartments, etc. Application of the FRET concept allows determining
donor-acceptor interchromophoric distances. In addition, anisotropy measurements can
be related to the orientation of the drug within the binding sites, where the degrees of
freedom for conformational relaxation are restricted. Transient absorption spectroscopy
is also a potentially powerful tool to investigate the binding of drugs to proteins, where
formation of encapsulated triplet excited states is favoured over other possible processes
leading to ionic species (i. e. radical ions), and their photophysical properties are
markedly sensitive to the microenvironment experienced within the protein binding
sites. Even under aerobic conditions, the triplet lifetimes of protein-complexed drugs are
remarkably long, which provides a broad dynamic range for identification of distinct
triplet populations or for chiral discrimination. Specific applications of the laser flash
photolysis technique include the determination of drug distribution among the bulk
solution and the protein binding sites, competition of two types of proteins to bind a
3
drug, occurrence of drug-drug interactions within protein binding sites, enzymatic-like
activity of the protein or determination of enantiomeric compositions.
The use of proteins as supramolecular hosts modifies the photoreactivity of
encapsulated substrates by providing protection against oxygen or other external
reagents, by imposing conformational restrictions in the binding pockets, or by
influencing the stereochemical outcome. In this review, a selected group of examples is
presented including decarboxylation, dehalogenation, nucleophilic addition,
dimerisation, oxidation, Norrish type II reaction, photo-Fries rearrangement and 6
electrocyclisationFinancial support from the Spanish Government (CTQ2010-14882, JCI-2011-09926, RyC-2007-00476), from the EU (PCIG12-GA-2012-334257), from the Universitat Politènica de València (SP20120757) and from the Consellería de Educació, Cultura i Esport (PROMETEOII/2013/005, GV/2013/051) is gratefully acknowledged.Vayá Pérez, I.; Lhiaubet-Vallet, VL.; Jiménez Molero, MC.; Miranda Alonso, MÁ. (2014). Photoactive assemblies of organic compounds and biomolecules: drug-protein supramolecular systems. Chemical Society Reviews. 43:4102-4122. https://doi.org/10.1039/C3CS60413FS410241224
Distinct molecular signatures of clinical clusters in people with type 2 diabetes:an IMI-RHAPSODY study
Type 2 diabetes is a
multifactorial disease with multiple underlying aetiologies. To address this
heterogeneity a previous study clustered people with diabetes into five diabetes
subtypes. The aim of the current study is to investigate the aetiology of these
clusters by comparing their molecular signatures. In three independent cohorts,
in total 15,940 individuals were clustered based on five clinical
characteristics. In a subset, genetic- (N=12828), metabolomic- (N=2945),
lipidomic- (N=2593) and proteomic (N=1170) data were obtained in plasma. In
each datatype each cluster was compared with the other four clusters as the
reference. The insulin resistant cluster showed the most distinct molecular
signature, with higher BCAAs, DAG and TAG levels and aberrant protein levels in
plasma enriched for proteins in the intracellular PI3K/Akt pathway. The obese
cluster showed higher cytokines. A subset of the mild diabetes cluster with
high HDL showed the most beneficial molecular profile with opposite effects to
those seen in the insulin resistant cluster. This study showed that clustering
people with type 2 diabetes can identify underlying molecular mechanisms
related to pancreatic islets, liver, and adipose tissue metabolism. This
provides novel biological insights into the diverse aetiological processes that
would not be evident when type 2 diabetes is viewed as a homogeneous diseas
Effects of a Weight Loss Intervention on Body Mass, Fitness, and Inflammatory Biomarkers in Overweight or Obese Breast Cancer Survivors
Neural correlates of attention-executive dysfunction in lewy body dementia and Alzheimer's disease.
Attentional and executive dysfunction contribute to cognitive impairment in both Lewy body dementia and Alzheimer's disease. Using functional MRI, we examined the neural correlates of three components of attention (alerting, orienting, and executive/conflict function) in 23 patients with Alzheimer's disease, 32 patients with Lewy body dementia (19 with dementia with Lewy bodies and 13 with Parkinson's disease with dementia), and 23 healthy controls using a modified Attention Network Test. Although the functional MRI demonstrated a similar fronto-parieto-occipital network activation in all groups, Alzheimer's disease and Lewy body dementia patients had greater activation of this network for incongruent and more difficult trials, which were also accompanied by slower reaction times. There was no recruitment of additional brain regions or, conversely, regional deficits in brain activation. The default mode network, however, displayed diverging activity patterns in the dementia groups. The Alzheimer's disease group had limited task related deactivations of the default mode network, whereas patients with Lewy body dementia showed heightened deactivation to all trials, which might be an attempt to allocate neural resources to impaired attentional networks. We posit that, despite a common endpoint of attention-executive disturbances in both dementias, the pathophysiological basis of these is very different between these diseases.This work was supported by an Intermediate Clinical Fellowship . Grant Number: (WT088441MA) to John‐Paul Taylor
the National Institute for Health Research (NIHR), and Newcastle Biomedical Research Unit (BRU) based at Newcastle upon Tyne Hospitals NHS Trust, Newcastle University
The status of the world's land and marine mammals: diversity, threat, and knowledge
Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
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