11 research outputs found
Cerebrospinal fluid sodium rhythms
Background: Cerebrospinal fluid (CSF) sodium levels have been reported to rise during episodic migraine. Since
migraine frequently starts in early morning or late afternoon, we hypothesized that natural sodium chronobiology
may predispose susceptible persons when extracellular CSF sodium increases. Since no mammalian brain sodium
rhythms are known, we designed a study of healthy humans to test if cation rhythms exist in CSF.
Methods: Lumbar CSF was collected every ten minutes at 0.1 mL/min for 24 h from six healthy participants. CSF
sodium and potassium concentrations were measured by ion chromatography, total protein by fluorescent
spectrometry, and osmolarity by freezing point depression. We analyzed cation and protein distributions over the
24 h period and spectral and permutation tests to identify significant rhythms. We applied the False Discovery Rate
method to adjust significance levels for multiple tests and Spearman correlations to compare sodium fluctuations
with potassium, protein, and osmolarity.
Results: The distribution of sodium varied much more than potassium, and there were statistically significant
rhythms at 12 and 1.65 h periods. Curve fitting to the average time course of the mean sodium of all six subjects
revealed the lowest sodium levels at 03.20 h and highest at 08.00 h, a second nadir at 09.50 h and a second peak
at 18.10 h. Sodium levels were not correlated with potassium or protein concentration, or with osmolarity.
Conclusion: These CSF rhythms are the first reports of sodium chronobiology in the human nervous system. The
results are consistent with our hypothesis that rising levels of extracellular sodium may contribute to the timing of
migraine onset. The physiological importance of sodium in the nervous system suggests that these rhythms may
have additional repercussions on ultradian functions
WTO must ban harmful fisheries subsidies
Sustainably managed wild fisheries support food and nutritional security, livelihoods, and cultures (1). Harmful fisheries subsidies—government payments that incentivize overcapacity and lead to overfishing—undermine these benefits yet are increasing globally (2). World Trade Organization (WTO) members have a unique opportunity at their ministerial meeting in November to reach an agreement that eliminates harmful subsidies (3). We—a group of scientists spanning 46 countries and 6 continents—urge the WTO to make this commitment..
Global COVID-19 lockdown highlights humans as both threats and custodians of the environment
The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness