Showing posts with label Blastocystis. Show all posts
Showing posts with label Blastocystis. Show all posts

Tuesday, July 10, 2018

Updates on 2nd International Blastocystis Conference

Three months until kick-off of 2nd International Blastocystis Conference in Bogotá!

A couple of updates:

  • Abstract submission deadline has been postponed to 15th of August 2018
  • We have had a couple of speaker cancellations. Drs Pauline Scanland and Katerina Pomajbikova will not be able to participate. Hopefully, we'll be blessed by their presence at the next big Blasto event. Instead, Drs Raul Tito-Tadeo and Hisao Yoshikawa have very kindly accepted to give keynote lectures and lead workshop sessions. And so we will still have a great event!
For more information on workshop and conference, please visit the official conference website here.

Since it's summer here in Europe, and since I love Phlox, I thought, I'd attach a couple of images that I received yesterday from my dear friend Jaco Verweij.


Tuesday, July 3, 2018

Experimental models for Blastocystis research - new paper out!

Experimental models are critical to advancing our knowledge on the role of Blastocystis in health and disease.

We have now published our work led by Dr Katerina Pomajbikova on the suitability of the rat as a model of Blastocystis colonisation. We observed that the rats were able to sustain the colonisation for more than one year, when a ST1 strain isolated from a human was used.

Next step could now be to monitor gut microbiota before and after challenge with Blastocystis cysts and look for changes at both individual and community level,, changes in alpha and beta diversity, etc.

The paper is free for download here until August 19, 2018.

Friday, June 22, 2018

Updates on 2nd International Blastocystis Conference in Bogotá!

Hi everyone,

There's only little more than three months before the kick-off of our 2nd International Blastocystis Conference! And as in the case of our 1st conference in Ankara in 2015, participants are in for a real treat! I simply don't know where to begin... !



Well, for starters, here's the hotel in which the conference will take place (11–12 October). It's the Hotel Estelar La Fonata in Bogotá! I think it looks amazing!

Prior to the very conference (9–10 October), there will be a two-day workshop at Universidad del Rosario - Quinta De Mutis.

Please go to the conference website and find more information: http://www.urosario.edu.co/Blastocystis/en/home/

The line-up of faculty members is impressive; again, please visit website to update yourself with workshop leaders and keynote speakers.

We will be dealing with anything from diagnostics to genomics, from epidemiology to cell biology, from experimental models to phylogenetics!

There will be plenty of Colombian coffee to sample and you might also with to sign up for the gala dinner!

So, don't miss out on the opportunity to put yourself into the very epicentre of Blastocystis research and experience the dynamic city of Bogotá!

Importantly, the deadline for abstract submission is 1st of July, so please everyone: Get your act together - submit your abstract today and support us with your presence and your enthusiasm with regard to the most common parasite in the human gut: Blastocystis!

SEE YOU THERE!!!

Image result for sun emoji

Wednesday, March 21, 2018

More on Blastocystis and Gut Bacteria...

As an appropriate follow-up on yesterday's post, I feel like guiding your attention to the paper by Laforest-Lapointe and Arrieta from University of Calgary, Canada with the title 'Microbial Eukaryotes: a Missing Link in Gut Microbiome Studies', which elaborates on some of the issues that we have already been highlighting several times in the past.

Nevermind, in their article, which just appeared in the ASM-based journal "mSystems", they speculate that the reason for the observed link between Blastocystis colonisation and increased bacterial diversity (which was mentioned several times in the paper that I referred to yesterday) might be due to predation by Blastocystis on bacteria, a process which selects for higher diversity. They argue that

"In the absence of Blastocystis, a strong bacterial competitor dominates the community, which limits species richness and community evenness; when [Blastocystis is] present, its predation on abundant bacterial taxa lowers the competition for nutrients and space, which leads to an increase in bacterial richness and community evenness."

Since predation on bacteria by Blastocystis has only been documented once (I believe) to date, the authors are right in encouraging colleagues to study engulfment of bacteria by Blastocystis.

Those of us who take a special interest in the public health impact of common intestinal parasites and who work in the field of clinical microbiology and infectious diseases might benefit from taking some lessons from experts in 'food web theory' and micro- and macroecology.

The article can be accessed here.

Tuesday, March 20, 2018

Associations Between Intestinal Parasites and Bacteria

For those interested in exploring the presence/absence of intestinal parasites in a gut microbiome context, Dr Mark van der Giezen and I did this small opinion paper for Trends in Parasitology. In it, we summarize data from studies looking at the associations between single-celled intestinal (luminal) parasites and gut bacteria, and we tried to come up with a hypothesis for the factors governing the presence/absence of e.g. Blastocystis.

The paper just appeared online, and you can access it here.



Wednesday, February 21, 2018

PhD position available in Pauline's lab

Message from Dr Pauline D Scanlan (view personal website here):


Friday, October 13, 2017

Official Poster for the 2nd International Blastocystis Conference

Thanks to Juan-David Ramirez Gonzales and his colleauges, the official poster for the 2nd International Blastocystis Conference is now available.

I put it on Google Drive as a pdf file, which you can download here. Please share it on facebook. Please also print it and use it to adorn your institutes, hospital departments, offices, canteens, homes, etc... Thanks!



Monday, July 31, 2017

Trends in Blastocystis Research

I thought I'd post two current conference abstracts to exemplify some of the trends in  Blastocystis research.

The first is from Dr Pauline D Scanlan, who will be speaking at 15th International Congress of Protistology currently taking place in Prague. Go here for more info about the meeting.

In the symposium 'The eukaryome, bringing protists into the spotlight of microbiome research' taking place today, Pauline will be giving a talk with the title:


Inter-Kingdom Interactions in the human gut microbiome-the prevalence of the intestinal protist Blastocystis is linked to host age, antibiotic use and gut bacterial diversity and composition

and the abstract reads like this:



The human gut is host to a complex microbial ecosystem that plays a central role in host health. In addition to bacteria, viruses and archaea, the gut microbiota includes a diversity of fungal and protist species that are collectively referred to as the gut ‘eukaryome’. Although research into the gut eukaryome is in its infancy, emerging data indicates that the intestinal protist Blastocystis is perhaps the most common member of the human gut eukaryome worldwide. Despite its association with intestinal disease, asymptomatic carriage is common with Blastocystis frequently observed in surveys of the healthy adult gut microbiome. Furthermore, Blastocystis is less prevalent in chronic diseases such as Irritable Bowel Syndrome compared to healthy controls. Antibiotic administration significantly reduces Blastocystis prevalence rates between case and controls groups with the reduction in Blastocystis prevalence in the antibiotic treated group possibly due to direct effects on Blastocystis and/or secondary loss due to loss of bacteria that Blastocystis interacts with. In support of this latter hypothesis, data showing correlations between the presence of Blastocystis and specific features of the bacterial component of the gut microbiome (high diversity and a specific bacterial composition) are suggestive of inter-kingdom interactions between bacteria and Blastocystis in the gut microbiome. Blastocystis is less prevalent in infant populations relative to contemporaneous adult populations indicating that Blastocystis is not adapted to the infant gut. Given the difference in microbiome composition and diversity in infants compared to adults perhaps Blastocystis requires a more adult-like gut microbiome for successful colonisation. Collectively, emerging data suggests that successful colonisation of the gut by Blastocystis is linked to the composition and diversity of the bacterial fraction of human gut microbiome. Consequently, interactions between Blastocystis and bacteria in the gut microbiome may account for some of the variation in prevalence rates observed across age, health and geography.
 
Along similar lines, I will be giving a talk at the EMBO conference 'Anaerobic protists: Integrating Parasitology with mucosal microbiota and immunology' running from 31 AUG to 03 SEP in Newcastle, UK. You can read about the conference here.

The title and abstract of my talk are as follows:

The diversity of the most common intestinal protists, Blastocystis and Dientamoeba, and their interactions with the microbiota: what role in health and disease?


The integration of DNA-methods in Clinical Microbiology has enabled a more detailed and accurate snapshot of the protists colonising and infecting our guts. Parasites like Blastocystis and Dientamoeba are much more common than previously known, when detection relied mainly on microscopy of faecal concentrates and smears only.
While Dientamoeba isolated from humans exhibits very little genetic variation across the small subunit ribosomal gene, Blastocystis displays a perplexing amount of genetic heterogeneity, and nine subtypes, which are arguably separate species, have been found in humans. Subtypes 1 to 4 account for about 95% of human Blastocystis carriage.
It is expected that over 1 billion people are colonised by Blastocystis, and based on DNA-based detection, prevalence figures of up to 100% have been reported in developing countries. Conversely, the prevalence of Blastocystis appears relatively low in e.g. the US, and it has been suggested that the low prevalence is indicative of the defaunation of indviduals adapting a Westernized life style.
In a developed country like Denmark, the prevalence of Blastocystis and Dientamoeba is highest in individuals without gastrointestinal, while the prevalence of these parasites is lower in patients with functional and organic bowel disease, suggesting that these parasites are in fact markers of gastrointestinal health.
This is also in part exemplified by recent independent data linking high gut microbiota diversity to the presence of these parasites. Certain bacterial populations appear to be linked to parasite carriage, and studies are emerging that try to look into the association between these parasites and the remaining gut microbiota.
Moreover, higher age appears to be linked to Blastocystis colonisation. Blastocystis is more common in older children and adults, while in younger children, Dientamoeba is much more common.
Whether these parasites are able to modulate gut microbiota structure and function remains unknown, and it also remains to be demonstrated whether certain microbiota communities and/or metabolites are required for successful establishment of these parasites. More research data on these topics will inform future advances in probiotics in particular and gut microbiota manipulation in general.

 Thanks for your time.