Friday, September 10, 2021

Olfactory Training for Olfactory Dysfunction


Parking this here for future reference, and for anyone still having trouble getting their sense of smell back:

Hura N, Xie DX, Choby GW, Schlosser RJ, Orlov CP, Seal SM, Rowan NR. Treatment of post-viral olfactory dysfunction: an evidence-based review with recommendations. Int Forum Allergy Rhinol. 2020 Sep;10(9):1065-1086. doi: 10.1002/alr.22624. Epub 2020 Jun 25. PMID: 32567798; PMCID: PMC7361320. https://pubmed.ncbi.nlm.nih.gov/32567798/

Background: Post-viral olfactory dysfunction (PVOD) is one of the most common causes of olfactory loss. Despite its prevalence, optimal treatment strategies remain unclear. This article provides a comprehensive review of PVOD treatment options and provides evidence-based recommendations for their use.

Methods: A systematic review of the Medline, Embase, Cochrane, Web of Science, Scopus, and Google Scholar databases was completed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies with defined olfactory outcomes of patients treated for PVOD following medical, surgical, acupuncture, or olfactory training interventions were included. The Clinical Practice Guideline Development Manual and Conference on Guideline Standardization (COGS) instrument recommendations were followed in accordance with a previously described, rigorous, iterative process to create an evidence-based review with recommendations.

Results: From 552 initial candidate articles, 36 studies with data for 2183 patients with PVOD were ultimately included. The most common method to assess olfactory outcomes was Sniffin' Sticks. Broad treatment categories included: olfactory training, systemic steroids, topical therapies, a variety of heterogeneous non-steroidal oral medications, and acupuncture.

Conclusion: Based on the available evidence, olfactory training is a recommendation for the treatment of PVOD. The use of short-term systemic and/or topical steroids is an option in select patients after careful consideration of potential risks of oral steroids. Though some pharmacological investigations offer promising preliminary results for systemic and topical medications alike, a paucity of high-quality studies limits the ability to make meaningful evidence-based recommendations for the use of these therapies for the treatment of PVOD.

And don't forget:
Monell Center Scientists Find that Insulin is Necessary for Repairing Olfactory Neurons: Findings Point to Possible Treatment for Smell Loss
May 2021 - Monell Center

Thursday, September 9, 2021

Dark Taxa AKA Creating Taxonomies From Scratch


New norms needed to name never-seen fungi
May 2021, phys.org

There's 150,000 species of fungi known, yet a projected 2.2 to 3.8 million still waiting to be discovered (these are called dark taxa). But because of advances in DNA sequencing and microscopy, we're learning so fast that we need a new way to organize it all. 

This comes up in the context of biosecurity, where it can only work if "organisms detected can be reliably identified and have accurate names." For fungi, that's not really possible, because believe it or not, we don't have a good catalog of fungi. 
-via: Robert Lücking et al. Fungal taxonomy and sequence-based nomenclature, Nature Microbiology (2021). DOI: 10.1038/s41564-021-00888-x

We also don't have a good way to organize the words we use to describe everyday smells, and we don't have something like a "smell taxonomy." There are plenty of sub-domains that organize their relevant smells, found in subjects like coffee, wine, perfume, and culinary arts. They always seem to take the form of a wheel (not the most complex form). You can get a good start with everyday smells at the South Coast Air Quality Management District, who created a "Characterization of Odor Nuisance" odor wheel, with the help of environmental scientist Jane Curren at UCLA circa 2016. It was based on a bunch of phone calls made to the District where people were complaining about odors in their neighborhood. She took all the words they used and organized them. 

You could also look into Ann-Sophie Barwich who is a cognitive scientist who did her dissertion on olfactory categorization, and then wrote a book called Smellosophy. Probably one of the most interesting academics you will ever hear of. I mean, her master's thesis was about the relevance of  Leibniz causality on biological classification.

Image credit: Penicillin, Kew Royal Botanical Gardens for BBC

Notes:
State of the World's Fungi, by the Kew Royal Botanical Gardens (2018), is the first ever State of the World's Fungi report revealing how important fungi are to all life on Earth. [pdf]
[State of the World's Fungi]

International Commission on the Taxonomy of Fungi (ICTF)

MycoBank is the on-line repository and nomenclatural registry provided in collaboration between the International Mycological Association and the Westerdijk Fungal Biodiversity Institute. It provides a free service to the mycological and scientific society by databasing mycological nomenclatural novelties (new names and combinations) and associated data, such as descriptions, illustrations and DNA barcodes. Nomenclatural novelties are each allocated a unique MycoBank number to be cited in the publication where the nomenclatural novelty is introduced, to conform with the requirements of the International Code of Nomenclature for algae, fungi and plants.

Identification and quantification of nuisance odors at a trash transfer station. Jane Curren, et al.  PubMed, Waste Manag. 2016 Dec;58:52-61. doi: 10.1016/j.wasman.2016.09.021. Epub 2016 Sep 28.

Post Script:
I'm looking at a popular science article about fungi. The first two "interesting" points, when looked at together, remind me of why I always have the feeling like fungi are from outerspace:
  • Fungi are in a kingdom of their own but are closer to animals than plants
  • They have chemicals in their cell walls shared with lobsters and crabs (you do know we're all becoming crabs, right?)