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Yes good management of expectations, and as we see it a negative result is also an informative outcome. We deserve to know one way or another. Yes, lots of studies looking for differences in the blood in the form of proteomics/metabolomics, ELISAs and so on, but not to specifically look for...

It was a lot of fun talking with you @Simon M and quite an honour to be featured in your blog! Audrey and I have both been a big fan of your science, science communication, and patient advocacy for years, so this is wonderful to see. We're trying our best to make sure it's a success - which to...

I gather there are ways of doing this on genomic data that are not based on related individuals. There's one way that exploits linkage disequilibrium ( the property of a causal SNP to drag other nearby SNPs along with it just based on proximity), and the correlation of the chi squared value for...

1) Thank you! I'm glad you think so :) 2) I think that's basically right, just because the ones they agree on are not significant after multiple test correction. I don't think it's necessarily problematic that they disagree on lots of things though - the ones they disagree on that are most...

My understanding is the biggest parameter change is not VO2max, but a reduction in Ventilatory Threshold: The elbow where VCO2 begins to rapidly increase relative to VO2 due to a transition to anaerobic respiration. This - like RER - would be objective. I don't know about how anxiety might...

Interesting @Hutan and @SNT Gatchaman. Trying to get my head around what you're both saying correct me if I'm misunderstanding. [O2HbMb]-[HHbMb] is measuring roughly the same thing as SmO2 which is [O2Hb]/([O2Hb]+[HHB])x100. @SNT Gatchaman you are maybe suggesting you are having a more extreme...

Thank you :) They didn't do an analysis where they compared multiple datasets (from different papers). I mean that at baseline in their two day CPET paper (2022) they didn't report many metabolites having a difference between ME and HC. I think 7 metabolites. Then following exercise there were...

I've checked here using a linear model whether there is evidence for a given metabolite, that the two studies disagree in their fold change estimate (depends both on the fold change estimate but also the variance of the data). For the whole lot of common detected metabolites you can see the...

This makes sense about the metabolomics done at baseline but I think the two studies Hanson's group did across 4 time points over two CPETs are interesting. The blood plasma one argued changes in ME of metabolites relating to to urea cycle/glutamate/arginine/proline metabolism following...

Is this comparing the significant metabolites from at least one study? Or is it comparing all of the detected metabolites regardless of whether they were found to be different? It looks like most of the metabolites are hovering in a bubble around a fold change of one which suggests that the two...

In this figure panel they report on one of the top 2 significant metabolites associated with the difference between the first and second time point (before and after CPET 1). In controls this metabolite is elevated following exercise but unchanged in ME/CFS. This metabolite is unknown and has...

I wanted to make a post about this paper I think it's quite interesting. I like that by having a 4 time points and a longitudinal, paired design you partially mitigate problems with population noise. At baseline the differences between patients and controls are fairly minimal but over the time...

I love this! I was having a look through this data anyway and a resource like this would make it so much easier! It would be great (if and when you ever feel like you wanted to) if you could visualise the data for each metabolite as a scatter plot/maybe with a violin: 4 strips for ME - 1 for...

It's interesting to see strong positive agreement about gamma-glutamylated amino acids (glutamate, lysine, tryptophan etc) in @Murph 's comparison. These are amino acids which are attached to a glutamate(mine) at its gamma carbon position. They are made from the enzyme Gamma-glutamyl transferase...

This is cool I have a lot of thoughts about this. First thing is Hoel 2021 use serum and Germain 2018 use plasma. The metabolomes of serum and plasma differ in a few ways, most relevant here is serum have higher levels of amino acids than plasma. It's not totally clear why this is but it's...

Great article! George Monbiot is a very good ally

Thanks for this analysis Murph! Are these metabolites here significantly different in Baraniuk 2021? I had a quick skim but in the body of the paper they only report glutamate as changing and that's after exercise (in GWI). If not then the standard error on these fold change estimates could be...

I noticed that in the NIH paper some of the p values they report for their metabolites are higher than their adjusted p values. This doesn't make sense because the p value should increase after multiple test correction not decrease. I asked the authors about this: They were quick to respond...

Urea cycle: Carbamoyl phosphate synthesis is the rate limiting step of the urea cycle, it's formed from the combination of ammonia and bicarbonate. It's then attached to ornithine by ornithine transcarbamoylase. Ornithine is the precursor to putrescine which goes on to make spermidine and...

Oh yeah very good point. I haven't gone into that myself but if @LarsSG is right about this that's reassuring. To me it looks like maybe three pathways involved here. Purine metabolism, Urea cycle, Glutathione metabolism. Urea cycle and glutathione metabolism are linked closely to nitrogen...