Neural oscillatory anomalies in autism spectrum disorders (ASD) suggest an excitatory/inhibitory imbalance; however, the nature and clinical relevance of these anomalies are unclear. Whole-cortex ...magnetoencephalography data were collected while 50 children (27 with ASD, 23 controls) underwent an eyes-closed resting-state exam. A Fast Fourier Transform was applied and oscillatory activity examined from 1 to 120 Hz at 15 regional sources. Associations between oscillatory anomalies and symptom severity were probed. Children with ASD exhibited regionally specific elevations in delta (1–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), and high frequency (20–120 Hz) power, supporting an imbalance of neural excitation/inhibition as a neurobiological feature of ASD. Increased temporal and parietal alpha power was associated with greater symptom severity and thus is of particular interest.
Dating first cases of COVID-19 Roberts, David L; Rossman, Jeremy S; Jaric, Ivan
PLoS pathogens,
06/2021, Letnik:
17, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Questions persist as to the origin of the COVID-19 pandemic. Evidence is building that its origin as a zoonotic spillover occurred prior to the officially accepted timing of early December, 2019. ...Here we provide novel methods to date the origin of COVID-19 cases. We show that six countries had exceptionally early cases, unlikely to represent part of their main case series. The model suggests a likely timing of the first case of COVID-19 in China as November 17 (95% CI October 4). Origination dates are discussed for the first five countries outside China and each continent. Results infer that SARS-CoV-2 emerged in China in early October to mid-November, and by January, had spread globally. This suggests an earlier and more rapid timeline of spread. Our study provides new approaches for estimating dates of the arrival of infectious diseases based on small samples that can be applied to many epidemiological situations.
The most recent ice age was characterized by rapid and hemispherically asynchronous climate oscillations, whose origin remains unresolved. Variations in oceanic meridional heat transport may ...contribute to these repeated climate changes, which were most pronounced during marine isotope stage 3, the glacial interval 25 thousand to 60 thousand years ago. We examined climate and ocean circulation proxies throughout this interval at high resolution in a deep North Atlantic sediment core, combining the kinematic tracer protactinium/thorium (Pa/Th) with the deep water-mass tracer, epibenthic δ¹³C. These indicators suggest reduced Atlantic overturning circulation during every cool northern stadial, with the greatest reductions during episodic Hudson Strait iceberg discharges, while sharp northern warming followed reinvigorated overturning. These results provide direct evidence for the ocean's persistent, central role in abrupt glacial climate change.
Rhabdomyolysis-induced renal failure represents up to 15% of all cases of acute renal failure. Many studies over the past 4 decades have demonstrated that accumulation of myoglobin in the kidney is ...central in the mechanism leading to kidney injury. However, some discussion exists regarding the mechanism mediating this oxidant injury. Although the free-iron-catalyzed Fenton reaction has been proposed to explain the tissue injury, more recent evidence strongly suggests that the main cause of oxidant injury is myoglobin redox cycling and generation of oxidized lipids. These molecules can propagate tissue injury and cause renal vasoconstriction, two of the three main conditions associated with acute renal failure. This review presents the evidence supporting the two mechanisms of oxidative injury, describes the central role of myoglobin redox cycling in the pathology of renal failure associated with rhabdomyolysis, and discusses the value of therapeutic interventions aiming at inhibiting myoglobin redox cycling for the treatment of rhabdomyolysis-induced renal failure.
We investigate the possibility that long tidal tails formed during compact object mergers may produce optical transients powered by the decay of freshly synthesized r-process material. Precise ...modeling of the merger dynamics allows for a realistic determination of the thermodynamic conditions in the ejected debris. We combine hydrodynamic and full nuclear network calculations to determine the resultant r-process abundances and the heating of the material by their decays. The subsequent homologous structure is mapped into a radiative transfer code to synthesize emergent model light curves and determine how their properties (variability and color evolution) depend on the mass ratio and orientation of the merging binary. The radiation emanating from the ejected debris, though less spectacular than a typical supernova, should be observable in transient surveys and we estimate the associated detection rates. We find that it is unlikely that photometry alone will be able to distinguish between different binary mass ratios and the nature of the compact objects, emphasizing the need for spectroscopic follow-up of these events. The case for (or against) compact object mergers as the progenitors of short gamma-ray bursts can be tested if such electromagnetic transients are detected (or not) in coincidence with some bursts, although they may be obscured by on-axis afterglows.
Please cite this paper as: Hawkins T, Roberts J, Mangos G, Davis G, Roberts L, Brown M. Plasma uric acid remains a marker of poor outcome in hypertensive pregnancy: a retrospective cohort study. BJOG ...2012 2012;119:484–492.
Objective To examine the relationship between hyperuricaemia, haemoconcentration and maternal and fetal outcomes in hypertensive pregnancies.
Design Retrospective analysis of a database of hypertensive pregnancies.
Setting St George Hospital, a major obstetric unit in Australia.
Population A cohort of 1880 pregnant women without underlying hypertension or renal disease, referred for management of pre‐eclampsia or gestational hypertension.
Methods Demographic, clinical and biochemical data at time of referral and delivery were collected for each pregnancy. Women were grouped according to diagnosis (pre‐eclampsia or gestational hypertension) and logistic regression analysis was used to determine the relationship between uric acid, haemoglobin, haematocrit and adverse outcomes; an α level of P < 0.01 was used for statistical significance.
Main outcome measures Composites of adverse maternal and fetal outcomes.
Results In women with ‘benign’ GH (without proteinuria or any other maternal clinical feature of pre‐eclampsia) gestation‐corrected hyperuricaemia was associated with increased risk of a small‐for‐gestational‐age infant (OR 2.5; 95% CI 1.3–4.8) and prematurity (OR 3.2; 95% CI 1.4–7.2), but not with adverse maternal outcome. In the whole cohort of hypertensive pregnant women (those with pre‐eclampsia or gestational hypertension) the risk of adverse maternal outcome (OR 2.0; 95% CI 1.6–2.4) and adverse fetal outcome (OR 1.8; 95% CI 1.5–2.1) increased with increasing concentration of uric acid. Hyperuricaemia corrected for gestation provided additional strength to these associations. Haemoglobin and haematocrit were not associated with adverse pregnancy outcome.
Conclusions Hyperuricaemia in hypertensive pregnancy remains an important finding because it identifies women at increased risk of adverse maternal and particularly fetal outcome; the latter, even in women with gestational hypertension without any other feature of pre‐eclampsia.
Examination of resting state brain activity using electrophysiological measures like complexity as well as functional connectivity is of growing interest in the study of autism spectrum disorders ...(ASD). The present paper jointly examined complexity and connectivity to obtain a more detailed characterization of resting state brain activity in ASD. Multi-scale entropy was computed to quantify the signal complexity, and synchronization likelihood was used to evaluate functional connectivity (FC), with node strength values providing a sensor-level measure of connectivity to facilitate comparisons with complexity. Sensor level analysis of complexity and connectivity was performed at different frequency bands computed from resting state MEG from 26 children with ASD and 22 typically developing controls (TD). Analyses revealed band-specific group differences in each measure that agreed with other functional studies in fMRI and EEG: higher complexity in TD than ASD, in frontal regions in the delta band and occipital-parietal regions in the alpha band, and lower complexity in TD than in ASD in delta (parietal regions), theta (central and temporal regions) and gamma (frontal-central boundary regions); increased short-range connectivity in ASD in the frontal lobe in the delta band and long-range connectivity in the temporal, parietal and occipital lobes in the alpha band. Finally, and perhaps most strikingly, group differences between ASD and TD in complexity and FC appear spatially complementary, such that where FC was elevated in ASD, complexity was reduced (and vice versa). The correlation of regional average complexity and connectivity node strength with symptom severity scores of ASD subjects supported the overall complementarity (with opposing sign) of connectivity and complexity measures, pointing to either diminished connectivity leading to elevated entropy due to poor inhibitory regulation or chaotic signals prohibiting effective measure of connectivity.
Free radicals and oxidants are now implicated in physiological responses and in several diseases. Given the wide range of expertise of free radical researchers, application of the greater ...understanding of chemistry has not been uniformly applied to biological studies. We suggest that some widely used methodologies and terminologies hamper progress and need to be addressed. We make the case for abandonment and judicious use of several methods and terms and suggest practical and viable alternatives. These changes are suggested in four areas: use of fluorescent dyes to identify and quantify reactive species, methods for measurement of lipid peroxidation in complex biological systems, claims of antioxidants as radical scavengers, and use of the terms for reactive species.
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•Dye oxidation alone is insufficient evidence for detection of reactive species in biology.•Nonenzymatic lipid peroxidation assessment requires product analysis by mass spectroscopy.•Antioxidant claims require quantitative dose–response lowering of oxidative stress.•“ROS” and “RNS” should be used only when defined and the actual species are unknown.
The mega river ecosystem of the Yangtze River was once home to diverse aquatic megafauna but is increasingly affected by various anthropogenic stressors that have resulted in continuous loss of ...biodiversity, such as the probable extinction of Yangtze River Dolphin. The Chinese paddlefish, Psephurus gladius, was one of only two extant members of a relict lineage that was most diverse and widespread 34–75 million years ago. It is also one of the largest freshwater fish species, reaching up to 7 m in length. The Chinese paddlefish was once common in the Yangtze River, with c.25 t being harvested per annum during the 1970s. Populations have, however, declined drastically since the late 1970s as a result of overfishing and habitat fragmentation. Here, a basin-wide capture survey during 2017–2018 found 332 fish species, but did not find a single specimen of Chinese paddlefish. Furthermore, 140 historically reported fish species have not been found and most of them are considered highly endangered. Based on 210 sightings of Chinese paddlefish during the period 1981–2003, we estimated the timing of extinction to be by 2005, and no later than by 2010. In addition, the paddlefish probably became functionally extinct (i.e. it was unable to reproduce) by 1993, before it went extinct. It is likely that the lack of reproduction was among the major causes of extinction. As no individuals exist in captivity, and no living tissues are conserved for potential resurrection, the fish should be considered extinct according to the IUCN Red List criteria. The delayed extinction of Chinese paddlefish resulted from multiple threats, suggesting that optimizing conservation efforts on endangered Yangtze fauna is urgently needed.
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•The giant Chinese paddlefish (up to 7 m in length) was found to be extinct.•The timing of extinction was estimated to be by 2005–2010.•The paddlefish became functionally extinct by 1993, prior to extinction•Conservation efforts on endangered Yangtze fishes are urgently needed.
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